WorldWideScience

Sample records for w7-x superconducting coils

  1. Lessons learned from the manufacture of the W7-X planar coils

    International Nuclear Information System (INIS)

    Viebke, H; Gustke, D; Rummel, T; Sborchia, C; Schroeder, R; Williams, D; Bates, S; Leigh, B; Winter, R

    2006-01-01

    WENDELSTEIN 7-X (W7-X) is a superconducting stellarator. The planar coils are in charge to modify the magnetic filed configuration of the W7-X. The major challenges during manufacturing were the fabrication of the cable-in-conduit conductor, the accuracy of the coil cases after welding and machining and the development of electrical joints with a resistance below 1 nΩ. Leaks were detected during repetitive in the case cooling system, which were caused by stress corrosion cracking. High voltage tests in a reduced vacuum environment (Paschen conditions) revealed that the insulation had to be reinforced and the quench detection wires had to be exchanged. This paper gives an overview about the main technical challenges of the planar coils and the lessons learned during production

  2. Lessons learned from the manufacture of the W7-X planar coils

    Science.gov (United States)

    Viebke, H.; Gustke, D.; Rummel, T.; Sborchia, C.; Schroeder, R.; Williams, D.; Bates, S.; Leigh, B.; Winter, R.

    2006-06-01

    WENDELSTEIN 7-X (W7-X) is a superconducting stellarator. The planar coils are in charge to modify the magnetic filed configuration of the W7-X. The major challenges during manufacturing were the fabrication of the cable-in-conduit conductor, the accuracy of the coil cases after welding and machining and the development of electrical joints with a resistance below 1 nΩ. Leaks were detected during repetitive in the case cooling system, which were caused by stress corrosion cracking. High voltage tests in a reduced vacuum environment (Paschen conditions) revealed that the insulation had to be reinforced and the quench detection wires had to be exchanged. This paper gives an overview about the main technical challenges of the planar coils and the lessons learned during production.

  3. Review of the acceptance tests of the W7-X superconducting magnets

    International Nuclear Information System (INIS)

    Ehmler, H.; Baldzuhn, J.; Genini, L.; Heyn, K.; Sborchia, C.; Schild, T.

    2007-01-01

    The W7-X magnet system consists of 50 non-planar coils of five different types and 20 planar coils of two different types. Factory tests of the non-planar coils are carried out at the manufacturer site of Babcock-Noell, Germany, and for the planar coils at Tesla Engineering, UK. They consist of electrical insulation checks, mass flow measurements, leak tests and sensor checks. In the test facility of CEA Saclay, France, each coil is cooled down to ∼5 K and operated at nominal current. At least one coil of each type is quenched by increasing the inlet temperature. Results of the mass flow measurements and the quench tests are presented. The manufacturing and testing progress is reviewed and the impact of technical failures is discussed. In conclusion, the scope of the tests allows a very strict quality control. This experience is highly beneficial for the construction and testing of similar components for future superconducting fusion experiments

  4. Change of manufacturing technique for the W7-X nonplanar coil cases

    International Nuclear Information System (INIS)

    Gehring, M.; Schaefer, P.; Herrmann, K.D.; Scheller, H.

    2001-01-01

    The geometry of the coil cases of the nonplanar coil system for the Wendelstein 7-X (W7-X) experiment (Sapper, The superconducting magnet system for the W7-X stellarator. Proceedings 12th Topical Meeting on the Fusion Technology) was changed to a more complex shape compared to the DEMO Coil case (Kronhardt et al., 1998. Proceedings of the 20th SOFT (1998) 731-734). Therefore the manufacturing technique developed for the DEMO Coil case cannot be used for the series production of 50 coils. For the final design of the coil cases, investigations were performed to find a technique suitable for manufacturing the cases within the required geometrical tolerances and mechanical characteristics. In order to qualify the manufacturing technique a complete half case was cast and machined afterwards. The casting procedure was optimised with respect to the geometrical accuracy and the mechanical characteristics at 4.2 K. Measurements of the yield strength, the tensile strength, the elongation, and the Young's modulus were performed at room- and cryo-temperature (4 and 7 K). The influence of the heat treatment, the annealing temperature and the size of the casting on the mechanical values is shown. The requirements on the stainless steel are a yield strength of 800 MPa at 4 K and an elongation at fracture of >25%. The magnetic permeability has to be <1.01. Furthermore the welding properties of the case material were investigated. The development program showed that casting of complete case half shells is a feasible manufacturing technique for the series production of the Wendelstein 7-X nonplanar coil cases

  5. Design principles for handmade electrical insulation of superconducting joints in W7-X

    Energy Technology Data Exchange (ETDEWEB)

    Rummel, K., E-mail: kerstin.rummel@ipp.mpg.de [Max Planck Institute for Plasma Physics, EURATOM Association, Wendelsteinstr. 1, 17491 Greifswald (Germany); John, A. [Max Planck Institute for Plasma Physics, EURATOM Association, Wendelsteinstr. 1, 17491 Greifswald (Germany); Sulek, Z. [Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Krakow, Radzikowskiego 152 (Poland)

    2013-10-15

    Highlights: ► In W-7X there are several types of handmade electrical insulation. ► In general insulation based on impregnated glass tapes and special G10 pieces. ► A proper overlapping of glass tapes turned out to be mandatory. ► Detailed qualification and training helps to minimize the failure rate. ► Visual inspection and Paschen tests after every insulation steps are important. -- Abstract: The superconducting magnet system of the Wendelstein 7-X (W7-X) experiment consists of 50 non-planar and 20 planar coils, 121 bus bars and 14 current leads. The connection between bus bars, coils and current leads will be provided by 198 joints. The joints have to be insulated manually during the assembly of the machine in constraint positions and a tight environment. In general the insulation is based on glass tapes impregnated with epoxy resin and special G10 insulating pieces embedded in the glass tape insulation. In critical areas Kapton{sup ®}-foils are embedded in the insulation. All types of insulation were qualified at mock-ups in a 1:1 model of the expected environment in W7-X. The qualification programme comprises thermal cycling between room temperature and 77 K and high voltage tests under air, under vacuum and under reduced pressure (Paschen test). The paper describes the main principles used for different types of handmade Paschen-tight insulations in W7-X and the visual and electrical tests during and after assembly.

  6. Review of the Factory Acceptance Tests and Cold Tests of the W7-X Superconducting Magnets

    International Nuclear Information System (INIS)

    Ehmler, H.; Baldzuhn, J.; Genini, L.

    2006-01-01

    The W7-X magnet system consists of 50 non-planar coils of five different types and 20 planar coils of two different types. Factory acceptance tests of the non-planar coils are carried out at the manufacturer site of Babcock-Noell, Germany, and for the planar coils at Tesla Engineering, UK. They consist of electrical insulation checks, mass flow measurements and leak tests. In the test facility of CEA Saclay, France, each coil is cooled down to ∼ 6 K and operated at nominal current. At least one coil of each type is quenched by increasing the inlet temperature. The characteristic parameters of the quench tests (temperature, pressure, speed of normal-conducting zone, etc.) will be presented. Coils of the same type show a uniform behavior. The occurrences of leaks during cool-down on planar coils revealed quality problems with aluminum welds and stress corrosion of stainless steel tubes at the soldered connections with copper heat sinks. AC tests (impulse and impedance tests) were applied to detect short circuits during the fabrication of the winding packs. High voltage DC tests under vacuum and low gas pressure (Paschen-minimum conditions) revealed electrical insulation defects, which had not been found using standard high-voltage tests. These were mainly due to voids and cavities present in the winding pack after vacuum impregnation, insufficient glass-epoxy wrapped insulation and inappropriate design of the Kapton insulated quench detection cables. The mass flow measurements of the superconductor showed that the deviation between individual double layers of the coils is within acceptable limits. Two winding packs were given up by the supplier because of a superconductor blockage with resin and a short circuited winding, respectively. All other quality issues could be resolved by repair or changes in the components. The coil instrumentation with temperature sensors seems to be adequate. The strain gauges need improvements in temperature compensation and gluing

  7. Experience gained during Manufacture and Testing of the W7-X Superconducting Magnets

    International Nuclear Information System (INIS)

    Wanner, M.; Sborchia, C.; Risse, K.; Viebke, H.; Baldzuhn, J.

    2006-01-01

    The W7-X basic device is presently being assembled at the Greifswald branch of IPP. The specific field configurations of this helical advanced stellarator are realised by a symmetric arrangement of 50 non-planar and 20 planar superconducting coils. In order to sustain the large electromagnetic forces and moments, all coils are bolted to a massive coil support structure and supported against each other by inter-coil support elements. Cooling of superconductor and the casing is provided by supercritical helium. For all coils the same cable-in-conduit conductor is used. This conductor is formed by a NbTi cable which is co-extruded in an aluminium jacket. Low-resistive electrical joints connect the conductor layers within a winding package and potential break provide electrical insulation of the helium pipes. After insulation and vacuum pressure impregnation, the winding packages are embedded in stainless steel casings, which are then finish-machined and equipped with cooling pipes. During a rapid shut-down of the magnet system the windings may experience voltages up to several kilovolts. High voltage tests under degraded vacuum conditions (Paschen tests) provide a sensitive method to detect weak points in the electrical insulation. Manufacture of the magnets is in a well advanced stage. All winding packages are completed, many of them are integrated in the casings and several coils have already been delivered for cold testing. These tests are performed in a cryogenic test facility at CEA Saclay. Tests at nominal operating conditions and quench tests confirmed the electric layout and the specified margin. Design changes have been implemented during fabrication due to more detailed structural analyses. Some manufacturing processes had to be modified and re-qualified to allow repair of weaknesses defects found during tests. The presentation will give an overview of the production status of the superconducting coils, the experiences gained during fabrication of the

  8. Transition of W7-X non-planar coils from manufacturing to assembly

    Energy Technology Data Exchange (ETDEWEB)

    Ehrke, G. [Max-Planck-Institut fuer Plasmaphysik (IPP), EURATOM Association, Wendelsteinstrasse 1, D-17491 Greifswald (Germany)], E-mail: gunnar.ehrke@ipp.mpg.de

    2009-06-15

    The main magnetic field of Wendelstein 7-X fusion experiment (W7-X) at Max-Planck-Institut fuer Plasmaphysik Greifswald, Germany will be provided by 50 non-planar coils and supported by 20 planar coils. The non-planar coils were delivered by a consortium (CON) consisting of Babcock Noell GmbH Germany (BNG) and ASG Superconductors S.p.A. Italy (ASG). The coil production ended with the delivery of the last non-planar coil in March 2008 at the manufacturing branch of BNG in Zeitz, Germany. The construction of the coils was characterised by design changes, many rework actions and resulting time delays. Due to these numerous adjustments and changes a continuous improvement process was needed. This paper will give an overview about the transition of the non-planar coils from the acceptance tests at the manufacturer site to the beginning of the assembly at IPP. Furthermore this report will highlight technical interfaces in the period of transition.

  9. Completion of designing and manufacturing of the coil support structure of W7-X

    International Nuclear Information System (INIS)

    Chauvin, Didier; Koppe, Torsten; Cardella, Antonio; Missal, Bernd; Pilopp, Dirk; Di Bartolo, Giovanni; Camin, Rocio; Gonzales, Ivan; Giordano, Luca; Langone, Stefano

    2011-01-01

    In February 2000, the project called coil support structure for the Wendelstein 7-X fusion machine was started. Since October 2009 the full production of this big (80 tons) and complex component is now completed and delivered at IPP Greifswald. The W7-X coil system consists of 20 planar and 50 non-planar coils. They are supported by a pentagonal 10 m diameter, 2.5 m high called coil support structure (CSS). The CSS is divided into five modules and each module consists of two equal half modules around the radial axis. Currently, the five modules were successfully assembled with the coils meeting the tight manufacturing tolerances. Designing, structural calculation, raw material procurement, welding and soldering technologies, milling, drilling, accurate machining, helium cooling pipe forming, laser metrology, ultra sonic cleaning and vacuum test are some of the key points used all along this successful manufacturing process. The lessons learned in the large scale production of this difficult kind of support structure will be presented as relevant experience for the realization of similar systems for future fusion devices, such as ITER.

  10. Design and Fabrication of the Superconducting Bussystem for the Stellarator W7-X

    International Nuclear Information System (INIS)

    Sauer, M.; Giesen, B.; Charl, A.

    2006-01-01

    In the framework of cooperation with the Max-Planck-Institute for plasma physics (IPP) essential work packages of the superconducting stellarator Wendelstein 7-X (which is presently under construction at Greifswald, Germany) have been taken over by the Forschungszentrum Juelich (FZJ). One of these packages is the design, construction, qualification, manufacturing and assembly of the superconducting three-dimensional bussystem and its appropriate supports. An overall concept of the project was elaborated with the goal to optimize manufacturing steps, to simplify the system assembly and to provide easy transportation. In order to compensate the magnetic stray fields generated by the bus currents and to facilitate the bus assembly, a suitable bus topology was developed. For checking the geometry of the bent buses and to examine the buses assembly a 1:1 model of one W7-X section (72 o ) has been built. An insulation set up was developed and different samples have been fabricated. For qualification the insulation was examined as follows: - high voltage insulation checks including measurements of the Paschen firmness, - thermal tests and mechanical bending under cryo-temperatures at 77 K, - leakage and high pressure tests to simulate quench situations and - vacuum compatibilities of the materials and methods used. The design will be shown, calculation of magnetic fields and forces are presented. For series production of the 121 buses a production line has been installed. The fabrication process and its main appropriate steps will be presented: 1. Straightening of the superconductor on a rolling machine 2. Rounding on a special turning lathe, required to facilitate 3-dimensional bending 3. Bending on a 3-D-bending machine 4. Checking of geometry on the 1:1 model 5. Electrical insulation and conductive lacquer coat applied by hand 6. Vacuum and high voltage test at several pressure steps (Paschen test) inside bellow tube 7. Transportation in bundle of 6 buses to Greifswald

  11. Final Test of the W7-X Control Coils Power Supply and its Integration into the Overall Control Environment

    International Nuclear Information System (INIS)

    Fuellenbach, F.; Rummel, T.; Pingel, S.; Laqua, H.; Mueller, I.; Jauregi, E.

    2006-01-01

    In order to be able to vary the magnetic configuration of WENDELSTEIN 7-X (W7-X) at the plasma edge and allow sweeping of the power across the divertor target plates 10 '' control coils '' are installed inside the plasma vessel behind the baffle plates of the divertor. The coils are made of a hollow copper profile with eight turns each. The dimensions of the coils are 2,05 m x 0,35 m x 0,35 m with a three dimensional shape to fit into the narrow space between the baffles and the wall of the plasma vessel. Each of the ten coils is supplied by independent power supplies each providing bi-directionally a direct current of 2500 A with high accuracy and low ripple. To allow sweeping the power deposition from the plasma across the target plates the power supplies provide an alternating current of up to 625 A with frequencies up to 20 Hz which is synchronised between the ten supplies in order to maintain the symmetry of the magnetic field. The total output current of a power supply is a superposition of a direct current and an alternating current, where both parts have to be independently adjustable. JEMA, Spain provided the complete set of power supplies which are based on 10 independent four-quadrant power supplies with a link rectifier and includes a cooling water unit, a dedicated distribution and a central control and visualization system. All ten power supply units and auxiliary systems have meanwhile been installed and finally tested at the W7-X site in Greifswald. The paper focuses on the results of the final tests and measures to integrate the power supply system to the overall control system including the central PLC and PC's for experiment control, data acquisition- and security systems. (author)

  12. The tests at Saclay of the stellarator W7X superconducting magnets

    International Nuclear Information System (INIS)

    Jacquemet, M.

    2000-05-01

    The tests on the superconducting magnets should allow to check at ambient or cryogenic temperature, the mechanical behaviour and the lack of leak from the conductor, the correct configuration of the cable in the pipe, the electric insulation, the magnet behaviour during a transition, the buckling and mechanical constraints on the whole. (N.C.)

  13. Processing of the quench detection signals in W7-X

    International Nuclear Information System (INIS)

    Birus, Dietrich; Schneider, Matthias; Rummel, Thomas; Fricke, Marko; Petry, Klaus; Ebersoldt, Andreas

    2009-01-01

    The Wendelstein 7-X (W7-X) project uses superconductive coils for generation of the magnetic field to keep the plasma. One of the important safety systems is the protection against quench events. The quench detection system of W7-X protects the superconducting coils, the superconducting bus bar sections and the high temperature superconductor of the current leads against the damage because of a quench and against the high stress by a fast discharge of the magnet system. Therefore, the present design of the quench detection system (QDS) uses a two-stage safety concept for discharging the magnetic system. This paper describes the present design of the system assembly from the quench detection unit (QDU) for the detection of the quench to the quench detection interface (QDI) to implement the two-stage safety concept.

  14. Neutrons at W 7-X

    Energy Technology Data Exchange (ETDEWEB)

    Junker, J.; Weller, A.

    1998-10-01

    The W 7-X deuterium plasma (18 MW NI, 4 keV, 1.5.10{sup 20} m{sup -3}) will produce 6.10{sup 16} neutrons during a 10 s pulse. A detailed geometrical model of the W 7-X experiment has been set up for the neutron transport calculations by the MCNP4B code (Monte Carlo neutron particle). The fast neutron flux (2.5 MeV) inside the torus is 100 times higher than inside the hall. The almost homogeneous thermal neutron flux inside the hall is reduced 30 times by doping the concrete walls with 700 ppm of boron. For a pulse scenario of 500 pulses per year the annual dose equivalent rate outside of the hall is down to the legally allowed level of 0.3 mSv/year, mainly by photons, due to the shielding of a 1.8 m thick concrete wall. The skyshine by the flux penetrating the 1.2 m thick concrete roof leads to 0.01 mSv/year at the fence. The structure of the experiment gets activated by the neutrons which for the chosen pulse scenario leads to a total activity varying between 2.6.10{sup 9} and 1.2.10{sup 13} Bq. The dominant isotopes are the superconductor compound ({sup 28}Al, {sup 66}Cu, {sup 94m}Nb) on the short timescale (min`s) and the steel components ({sup 51}Cr, {sup 54}Mn, {sup 60}Co) on the long timescale (months and years). For the austenitic steel a concentration of 50 ppm of Co has been assumed. After 10 years lifetime of the experiment it takes 4.8 years until the long living {sup 60}Co (T{sub 1/2} = 5.3 years) becomes the dominant radioactive isotope. Having waited for totally 10 years the specific activity has almost come down to 1.10{sup 5} Bq/to at which level a freely use of the material can be allowed.

  15. Development of Quench Detection System for W7-X

    International Nuclear Information System (INIS)

    Birus, Dietrich; Rummel, Thomas; Fricke, Marko; Petry, Klaus; Demattio, Horst

    2007-01-01

    The Quench Detection System of W7-X will consist of nearly 400 Quench Detection Units (QDU) for the fast and reliable supervision of the 70 superconducting coils and the 120 superconducting bus bar sections. There will be five control racks with about 80 QDU, a data acquisition unit, an ac-dc power supply with integrated dc UPS unit in each of the racks and a PC based data management system as an overlay structure. Each QDU will have a special analogue input circuit realised as a programmable half bridge front end with different polarity-sensing and limiting functions for suppressing high dynamic voltages. Special filter design is included for noise-suppression and over voltage protection. A reconfigurable control/arithmetic unit offers possibilities of future expansions (e.g. all digital evaluation). The QDU acquires and checks the differential voltages of the superconductors permanently. In case of a quench it triggers the fast discharge of the coils and the storage of the voltage signals on the memory unit. The quench signals are in the mV range and have to be clearly identified within a noisy and a high-voltage background within a few milliseconds. Each QDU transfers the stored signal dates via a high-speed RS485 serial interface with 20 kV optical isolation barrier to an industrial type data acquisition unit. A second optically isolated RS485-network enables interconnection of each QDU in the control rack (Compound-Mode of QDU). The QDU are designed with an internal failsafe, programmable self-test and redundancy feature, broken wire check of the quench detection cables and connectors inside and outside of the cryostat of W7-X. All QDU will be fed via an UPS supported 24 V dc bus through a high voltage isolated dc-dc transformer on each unit. The design of the Quench Detection System allows operation under high voltage levels of up to 8 kV and under magnetic stray field levels up to 30 mT. The front end is very well isolated and the outputs of the QDU are

  16. Development of Quench Detection Units for W7-X

    International Nuclear Information System (INIS)

    Birus, D.; Rummel, T.; Fricke, M.; Petry, K.; Demattio, H.

    2006-01-01

    The Quench Detection System of W7-X will consist of nearly 400 Quench Detection Units (QDU) for the fast and reliable supervision of the 70 superconducting coils and the 120 superconducting bus bar sections. There will be five control racks with about 80 QDU, a data acquisition unit, an AC-DC power supply with integrated DC-UPS unit in each of the racks and a PC based data management system as an overlay structure. Each QDU will have a special analogue input circuit realised as a programmable half bridge front end with different polarity-sensing and limiting functions for suppressing high dynamic voltages. Special filter design is included for noise-suppression and over voltage protection. A reconfigurable control/arithmetic unit offers possibilities of future expansions (e.g. all digital evaluation). The QDU acquires and checks the differential voltages of the superconductors permanently. In case of a quench it triggers the fast discharge of the coils and the storage of the voltage signals on the memory unit. The quench signals are in the mV range and have to be clearly identified within a noisy and a high-voltage background within a few milliseconds. Each QDU transfers the stored signal dates via a high-speed RS-485 serial interface with 20 KV optical isolation barrier to the data acquisition unit, an industrial system. A second optically isolated RS-485-network enables interconnection of each QDU in the control rack (Compound-Mode of QDU). The QDU are designed with an internal failsafe, programmable self test and redundancy feature, broken wire check of the quench detection cables and connectors inside and outside of the cryostat of W7-X. All QDU will be fed via an UPS supported 24 V DC bus through a high voltage isolated DC-DC transformer on each unit. The design of the QDU allows operation under high voltage levels of up to 8 kV and under magnetic stray field levels up to 30 mT. The front end is very well isolated and the outputs of the QDU are strictly

  17. Superconducting magnetic coil

    Science.gov (United States)

    Aized, Dawood; Schwall, Robert E.

    1996-06-11

    A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil.

  18. Superconducting coil protection

    International Nuclear Information System (INIS)

    Woods, E.L.

    1975-01-01

    The protection system is based on a two-phase construction program. Phase I is the development of a reliable hardwired relay control system with a digital loop utilizing firmware and a microprocessor controller. Phase II is an expansion of the digital loop to include many heretofore unmonitored coil variables. These new monitored variables will be utilized to establish early quench detection and to formulate confirmation techniques of the quench detection mechanism. Established quench detection methods are discussed and a new approach to quench detection is presented. The new circuit is insensitive to external pulsed magnetic fields and the associated induced voltages. Reliability aspects of the coil protection system are discussed with respect to shutdowns of superconducting coil systems. Redundance and digital system methods are presented as related topics

  19. Experience with High Voltage Tests of the W7-X Magnets in Paschen-Minimum Conditions

    International Nuclear Information System (INIS)

    Petersen-Zarling, B.M.; Risse, K.; Viebke, H.; Gustke, D.; Ehmler, H.; Baldzuhn, J.; Sborchia, C.; Scheller, H.

    2006-01-01

    The W7-X machine is a low-shear stellarator of the Wendelstein line, which is being assembled at the IPP Branch Institute of Greifswald, Germany. The machine features a superconducting magnet system with 50 non-planar and 20 planar magnets operated at about 6 T and discharged with peak voltage levels up to 6 kV. Following the factory tests, the magnets are delivered to CEA Saclay, France, for the final acceptance tests at cryogenic condition. A series of high voltage tests in air and vacuum are part of the final acceptance test. During these tests the quality of the insulation, especially the hand-wrapped ground insulation in the termination area, has proven not to be adequate. In order to improve the reliability of the insulation system and detect defects for early repair, high voltage tests in reduced pressure of air (Paschen-minimum conditions) have been added as part of the factory acceptance procedure. This has been implemented in the vacuum chambers of BNN/Ansaldo for the test of the 50 non-planar coils, while other tests have been carried out at CEA/Saclay after cold testing. IPP has also installed a vacuum tank to perform Paschen tests during the preparation of all the coils for assembly, including also the 20 planar coils which cannot be tested at the manufacturer Tesla. These tests have proven to be a powerful tool to detect hidden insulation defects and void/cavities in the primary impregnation system, which could not be detected otherwise with the standard high voltage tests. This paper will summarize the background and experience accumulated in about 2 years of Paschen tests on the W7-X coils, including a description of the equipment, main results and statistics, weak points detected and repaired on the coils, and possibilities of improvements in the development and production of the W7-X magnets. The importance and the need of Paschen tests as part of the acceptance procedure for superconducting magnets to be used in future projects will also be

  20. Edge modelling for W7-X

    International Nuclear Information System (INIS)

    Schneider, R.; Borchardt, M.; Riemann, J.; Bonnin, X.; Nuehrenberg, J.; Mutzke, A.

    2001-01-01

    The edge modelling activities for W7-X are summarized. The status of the new 3D SOL transport code BoRiS is presented, including an algorithm for calculation of magnetic coordinates and metric coefficients. In addition, the analysis of a toroidally averaged island topology with respect to the effect of drift and currents is discussed using the 2D B2-solps5.0 code. (author)

  1. Architecture of central control system for the 10 MW ECRH-plant at W7-X

    Energy Technology Data Exchange (ETDEWEB)

    Braune, H. [Max-Plank-Institut fuer Plasmaphysik, Euratom Association Teilinstitut Greifswald, Wendelsteinstrasse 1, D-17491 Greifswald (Germany)], E-mail: harald.braune@ipp.mpg.de; Brand, P. [Universitaet Stuttgart, Institut fuer Plasmaforschung Pfaffenwaldring 31, D-70569 Stuttgart (Germany); Erckmann, V.; Jonitz, L. [Max-Plank-Institut fuer Plasmaphysik, Euratom Association Teilinstitut Greifswald, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Leonhardt, W.; Mellein, D. [Forschungszentrum Karlsruhe, Association EURATOM-FZK, IHM, FZK, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Michel, G. [Max-Plank-Institut fuer Plasmaphysik, Euratom Association Teilinstitut Greifswald, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Mueller, G. [Universitaet Stuttgart, Institut fuer Plasmaforschung Pfaffenwaldring 31, D-70569 Stuttgart (Germany); Purps, F. [Max-Plank-Institut fuer Plasmaphysik, Euratom Association Teilinstitut Greifswald, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Schlueter, K.-H. [Universitaet Stuttgart, Institut fuer Plasmaforschung Pfaffenwaldring 31, D-70569 Stuttgart (Germany); Winkler, M. [Max-Plank-Institut fuer Plasmaphysik, Euratom Association Teilinstitut Greifswald, Wendelsteinstrasse 1, D-17491 Greifswald (Germany)

    2007-10-15

    Electron Cyclotron Resonance Heating (ECRH) is the main heating method for the Wendelstein 7-X stellarator (W7-X) which is presently under construction at IPP Greifswald. The mission of W7-X is to demonstrate the inherent steady state capability of stellarators at reactor relevant plasma parameters. A modular 10 MW ECRH-plant at 140 GHz with 1 MW CW-capability power for each module is also under construction to support the scientific objectives. The commissioning of the ECRH-plant is well under way; three gyrotrons are operational. The strict modular design allows to operate each gyrotron separately and independent from all others. The ECRH-plant consists of many devices such as gyrotrons and high voltage power supplies, superconductive magnets, collector sweep coils, gyrotron cooling systems with many water circuits and last but not least the quasi-optical transmission line for microwaves with remote controlled mirrors and further water cooled circuits. All these devices are essential for a CW operation. A steady state ECRH has specific requirements on the stellarator machine itself, on the microwave sources, transmission elements and in particular on the central control system. The quasi steady state operation (up to 30 min) asks for real time microwave power adjustment during the different segments of one stellarator discharge. Therefore, the ECRH-plant must operate with a maximum reliability and availability. A capable central control system is an important condition to achieve this goal. The central control system for the 10 MW ECRH-plant at W7-X comprises three main parts. In detail these are the voltage and current regulation of each gyrotron, the interlock system to prevent the gyrotrons from damages and the remote control system based on a hierarchy set of PLCs and computers. The architecture of this central control system is presented.

  2. Pendulum support of the W7-X plasma vessel: Design, tests, manufacturing, assembly, critical aspects, status

    Energy Technology Data Exchange (ETDEWEB)

    Missal, B., E-mail: bernd.missal@ipp.mpg.de [Max-Planck-Institut für Plasmaphysik, EURATOM Association, Teilinstitut Greifswald, Wendelsteinstraße 1, D-17491 Greifswald (Germany); Leher, F.; Schiller, T. [MAN Diesel and Turbo SE, Werftstraße 17, 94469 Deggendorf (Germany); Friedrich, P. [Universität Rostock, FB Maschinenbau und Schiffstechnik, Albert-Einsteins-Straße 2, 18051 Rostock (Germany); Capriccioli, A. [ENEA Frascati, Fusion Technology Unit, Frascati (Italy)

    2014-10-15

    Highlights: • Plasma vessel support has to allow vertical adjustment and horizontal passive movement. • Planar sliding tables with PTFE do not fulfill all requirements. • Pendulums can fulfill all requirements. • Geometry and material of spherical bearings had to be optimized in calculations and tests. • Optimized pendulums were manufactured and assembled. - Abstract: The superconducting helical advanced stellarator Wendelstein 7-X (W7-X) is under construction at the Max-Planck-Institut für Plasmaphysik (IPP) in Greifswald, Germany. The three dimensional shape of plasma will be generated by 50 non-planar magnetic coils. The plasma vessel geometry follows exactly this three dimensional shape of plasma. To ensure the superconductivity of coils a cryo vacuum has to be generated. Therefore the coils and their support structure are enclosed within the outer vessel. Plasma vessel, coil structures and outer vessel have to be supported separately. This paper will describe the vertical supports of plasma vessel which have to fulfill two special requirements, vertical adjustability and horizontal mobility. These two tasks will be carried out by plasma vessel supports (PVS) with hydraulic cylinders, special sliding tables during assembly and pendulum supports during operating phase. The paper will give an overview of design, calculation, tests, fabrication, assembly, critical aspects and status of PVS.

  3. The Integration of SME'S into Fusion Projects - Especially for the Manufacturing of Components for W7-X

    International Nuclear Information System (INIS)

    Heyn, K.; Scheller, H.; Andersson, H.

    2006-01-01

    The Consortium of Babcock Noell in Wuerzburg (Germany) and Ansaldo Superconduttori in Genoa (Italy) is producing the 50 nonplanar superconducting coils for the W7-X project. For the realization of the W7-X coils, especially for the manufacturing of the different components, an international network of companies is used, among them several SME's: highly specialized small and medium size enterprises. One of these SME's, which surpassed itself, is the Swedish foundry oesterby Gjuteri AB which has produced the stainless steel coil casings for W7-X. The design of the SS casings was changed by the customer after placing the contact. This has caused the question to manufacture the halfrings with cast segments or as entire castings, which lead finally to the contact with oesterby. A lot of effort was necessary to design the 10 different patterns for the 5 types of casings each consisting of 2 halfrings. The qualification of the SS grade for the high requirements of the project, among them the low cobalt content or the required mechanical properties at 4 K needed some time. Further on a lot of investigations about the test procedures were necessary to be applied for the special geometry of the product, for the 3D measurements or the NDT. The conventional x-ray was not completely suitable for this product due to the thickness of the material in some areas. The main production steps for each halfring will be presented in the paper. The testing includes different NDT, the material tests at RT and 4 K and the 3D measurement. The first casing was delivered end of 2001 and the last in autumn 2005 after several unexpected interruptions. All were treated in a close contact with the customer and in good collaboration between oesterby and BNG and have lead to a significant increase of competence on both sides. Several other SME's are involved in the network for W7-X realization. There are for example: C-CON in Rottenburg and its subcontractors PEM and KUKA in Schwarzenberg for Final

  4. Ten years of cryo-magnetic W7-X test facility construction and operation

    International Nuclear Information System (INIS)

    Renard, B.; Dispau, G.; Donati, A.; Genini, L.; Gournay, J.F.; Kuster, O.; Molinie, F.; Schild, T.; Touzery, R.; Vieillard, L.; Walter, C.

    2011-01-01

    The construction, commissioning, and operation phases of the W7-X cryo-magnetic test facility in CEA Saclay lasted ten years. The large diversity of equipments called, specialties involved and problems solved attest the expertise that was required to operate the test facility and test the coils. Nearly one hundred cryogenic tests were performed on the seventy W7-X coils, at a rate always increasing, using two cryostats each holding two coils. This paper presents the test facility and its operation first, the cryogenic difficulties that were confronted with their solutions, the electro-magnetic difficulties encountered along with corrective actions, and finally the instrumentation and data acquisition aspects. (authors)

  5. Radiation resistant ducted superconductive coil

    International Nuclear Information System (INIS)

    Schleich, A.

    1976-01-01

    The radiation-resistant ducted superconductive coil consists of a helically wound electrical conductor constituted by an electrically conductive core of superconductive material provided with a longitudinally extending cooling duct. The core is covered with a layer of inorganic insulating material and the duct is covered by an electrically conductive metallic gas-tight sheath. The metallic sheaths on adjacent turns of the coil are secured together. 2 Claims, 4 Drawing Figures

  6. Design of multichannel laser interferometry for W7-X

    International Nuclear Information System (INIS)

    Kornejew, P.; Hirsch, M.; Bindemann, T.; Dinklage, A.; Dreier, H.; Hartfuss, H.-J.

    2006-01-01

    An eight channel interferometer is developed for density feedback control and the continuous measurement of electron density profiles in the stellarator W7-X. An additional sightline is launched in the geometry of the Thomson scattering for cross calibration. Due to the W7-X coil geometry access is strongly restricted. This motivates the optimization of the sightline geometry and design studies for supplementary chords. In-vessel retroreflectors will be used and inserted in the first wall elements. To cope with associated mechanical vibrations and thermal drifts during the discharges with envisaged duration of 30 min either two-color or second harmonic interferometry techniques must be applied. Optimum wavelengths are found to be about 10 and 5 μm. A CO 2 /CO interferometer (10 μm/5 μm) will be tested and compared with an existing CO 2 /HeNe test interferometer. A special difficulty of remotely operated diagnostics is the need of long transmission lines with a path length of about 60 m required from the diagnostics location to the torus hall and back. Different arrangements will be compared

  7. Cooling device of superconducting coils

    International Nuclear Information System (INIS)

    Duthil, R.; Lottin, J.C.

    1985-01-01

    This device is rotating around an horizontal axis. The superconducting coils are contained in a cryogenic enclosure feeded in liquid helium forced circulation. They are related to an electric generator by electric mains each of them comprising a gas exchanger, and an exchanger-evaporator set between the cryogenic device and those exchangers. The exchanger-evaporator is aimed at dissipating the heat arriving by conductors connected to the superconducting coils. According to the invention, the invention includes an annular canalization with horizontal axis in which the connection conductors bathe in liquid helium [fr

  8. Large superconducting coil fabrication development

    International Nuclear Information System (INIS)

    Brown, R.L.; Allred, E.L.; Anderson, W.C.; Burn, P.B.; Deaderick, R.I.; Henderson, G.M.; Marguerat, E.F.

    1975-01-01

    Toroidal fields for some fusion devices will be produced by an array of large superconducting coils. Their size, space limitation, and field requirements dictate that they be high performance coils. Once installed, accessibility for maintenance and repairs is severely restricted; therefore, good reliability is an obvious necessity. Sufficient coil fabrication will be undertaken to develop and test methods that are reliable, fast, and economical. Industrial participation will be encouraged from the outset to insure smooth transition from development phases to production phases. Initially, practice equipment for three meter bore circular coils will be developed. Oval shape coil forms will be included in the practice facility later. Equipment that is more automated will be developed with the expectation of winding faster and obtaining good coil quality. Alternate types of coil construction, methods of winding and insulating, will be investigated. Handling and assembly problems will be studied. All technology developed must be feasible for scaling up when much larger coils are needed. Experimental power reactors may need coils having six meter or larger bores

  9. Superconducting poloidal coils for STARFIRE commercial reactor

    International Nuclear Information System (INIS)

    Wang, S.T.; Evans, K. Jr.; Turner, L.R.; Huang, Y.C.; Prater, R.; Alcorn, J.

    1979-01-01

    STARFIRE is considered to be the tenth commercial tokamak power plant. A preliminary design study on its superconducting poloidal coil system is presented. Key features of the design studies are: the elimination of the ohmic heating coil; the trade-off studies of the equilibrium field coil locations; and the development of a conceptual design for the superconducting equilibrium field coils. Described are the 100 kA cryostable conductor design, the coil structure, and evaluation of the coil forces

  10. Feasibility of a Heavy Ion Beam Probe for W7-X

    Science.gov (United States)

    Crowley, T. P.; Demers, D. R.; Fimognari, P. J.; Grulke, O.; Laube, R.

    2017-10-01

    A feasibility study of a Heavy Ion Beam Probe (HIBP) diagnostic for the Wendelstein 7-X (W7-X) superconducting stellarator, incorporating the accelerator and energy analyzer (currently in Greifswald) from the 2 MeV TEXT-U HIBP, is being carried out. The study's results are positive: beam trajectory simulations in the W7-X standard magnetic configuration, with central densities up to 1020 m-3, predict that it will be possible to measure the equilibrium plasma potential and Er at all radii, and simultaneously measure temporally and spatially resolved fluctuations of ne and potential for r / a >0.5. This will provide a unique capability to advance understanding of neoclassical and turbulent particle and energy transport in W7-X. Within this feasibility study, the beam is injected and detected through the K11 and N11 ports respectively, and the toroidal magnetic field is in the ` + φ ' direction. Additional beam simulations reveal that most radii can be accessed in 7 other paradigm magnetic configurations. It's anticipated that electrostatic beam steering suitable for studying all these configurations is plausible; it will have plate dimensions comparable to TEXT-U's with smaller electric fields and higher voltages. Initial estimates of anticipated heat load from the W7-X plasma on the steering systems indicate it will be significant, but tractable. Our conclusion from these studies is that an HIBP diagnostic for W7-X is feasible. This work is supported by US DoE Award DE-SC0013918.

  11. Superconducting cyclotron magnet coil short

    International Nuclear Information System (INIS)

    Mallory, M.L.; Blosser, H.G.; Clark, D.J.; Launer, H.; Lawton, D.; Miller, P.; Resmini, F.

    1982-01-01

    In February 1981, a short circuit appeared in the superconducting coil of the K500 cyclotron. The short is resistive in character and therefore has no effect on steady state operation of the magnet. The resistance of the short varies, sometimes being below threshold of detection as a heat load on the cooling system and sometimes being significant. The resistance under certain conditions shows approximately cyclic phenomena with time constants in the range of seconds and other approximately cyclic phenomena which correlate with gross operating parameters of the magnet (shifting current from one coil to another at high field and lowering and raising the liquid helium level). A number of diagnostic studies of the short have been made, using 1) an array of flux sensing loops to sense the magnetic effect of the short, 2) voltage comparisons between upper and lower sections of the coil, 3) comparisons of forces in the nine member coil support system and 4) the effect of the short on the thermal charactersitics of the coil. Insulation failure or a metal chip shorting out turns have been explored in some detail but a convincing determination of the exact cause of the short may never be available, (even the extreme step of unwinding the coil having a significant probability that an imperfection with the observed characteristics would pass unnoticed). Analysis of the characteristics of the short indicated that the most serious consequence would be failure of the coils mechanical support system in the event that the magnet was quickly discharged, as in a dump or quench. To deal with this hazard, the support system has been modified by installing solid supports which prevent the coil from moving by an amount sufficient to damage the support system. We have also reexamined the data and calculations used in the original coil design and have made some additional measurements of the properties of the materials (yield strength, friction coefficient, Young's modulus) used in the

  12. Shielding of the NBI boxes against W7-X magnetic stray fields

    Energy Technology Data Exchange (ETDEWEB)

    Kick, Manfred [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching (Germany)], E-mail: Kick@arcor.de; Sielanko, Juliusz [Maria Curie Sklodowska University, Pl. M. C. Sklodowskie 1, 20-031 Lublin (Poland); Heinemann, Bernd; Riedl, Rudolf; Speth, Eckehart; Staebler, Albrecht [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching (Germany)

    2009-06-15

    Neutral Beam Injection (NBI), besides ECRH, is foreseen as one of the main heating devices at the W7-X stellarator currently under construction at IPP Greifswald, Germany. In a final stage 20 MW of NBI heating power will be installed generated by two NBI boxes of the ASDEX Upgrade (AUG) type. Since magnetic fields generally affect the trajectories of charged particles, essentially all the NBI boxes - including ion sources, acceleration sections, neutralisers and deflection magnets - must be shielded against the stray fields of W7-X. In the magnetic stray fields of W7-X there exist significant radial and toroidal components whereas at tokamaks the vertical components are dominant. The power loads on the ion dump and the protecting structures of the deflecting magnets and the beam lines caused by residual beam ions, therefore, will be strongly different. Thus the shielding concept of AUG cannot simply be taken over, but must be carefully redesigned in order to remain below the critical power limits. New modelling calculations of the magnetic shielding, the ion trajectories and the resulting power loads have been carried out for the 'high iota' and 'low shear' experimental scenarios of W7-X. The fields taken for these calculations are modelled by averaging the calculated W7-X stray fields on the one hand, and by fields generated by two-hypothetical-planar coils perpendicular to the x-y plane, on the other hand. The shielding concept for W7-X mainly consist of iron plates in the outer side regions of the boxes and as little magnetic material as possible inside the boxes.

  13. ECRH and W7-X: An intriguing pair

    Science.gov (United States)

    Erckmann, V.; Braune, H.; Gantenbein, G.; Jelonnek, J.; Kasparek, W.; Laqua, H. P.; Lechte, C.; Marushchenko, N. B.; Michel, G.; Plaum, B.; Thumm, M.; Weissgerber, M.; Wolf, R.; W7-X ECRH Teams

    2014-02-01

    The construction of the W7-X basic machine is almost completed and the device is approaching the commissioning phase. W7-X operation will be supported by ECRH working at 140 GHz in 2nd harmonic X- or O-mode with 10 MW cw power. Presently the activities at W7-X concentrate on the implementation of wall-armour, in-vessel components and diagnostics. The ECRH-system is in stand by with 5 out of 10 gyrotrons operational. The status of both, the W7-X device and the ECRH system is reported. Further R&D activities concentrate on extending the launching capability for sophisticated confinement investigations with remote steering launchers in a poloidal plane with weak magnetic field gradient.

  14. Statistical analysis of the equilibrium configurations of the W7-X stellarator using Function Parameterization

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, A.; Geiger, J.; Mc Carthy, P. J.

    2005-07-01

    W7-X is a 5-period, fully optimised stellarator under construction at IPP-Greifswald, Germany. It has a standard magnetic configuration, with five islands at the boundary where iota=1, produced by a set of 2x5 modular field coils (MFC) in each period. The boundary iota value can be varied between 5/6 (low iota case) and 5/4 (high iota case) using 2x2 additional planar coils (PLC) per period. An important goal of W7-X is to investigate the steady state capabilities of fusion devices. For stellarators this essentially implies a real time monitoring of the discharges which have long pulse lengths, of the order of minutes. (Author)

  15. Statistical analysis of the equilibrium configurations of the W7-X stellarator using Function Parameterization

    International Nuclear Information System (INIS)

    Sengupta, A.; Geiger, J.; Mc Carthy, P. J.

    2005-01-01

    W7-X is a 5-period, fully optimised stellarator under construction at IPP-Greifswald, Germany. It has a standard magnetic configuration, with five islands at the boundary where iota=1, produced by a set of 2x5 modular field coils (MFC) in each period. The boundary iota value can be varied between 5/6 (low iota case) and 5/4 (high iota case) using 2x2 additional planar coils (PLC) per period. An important goal of W7-X is to investigate the steady state capabilities of fusion devices. For stellarators this essentially implies a real time monitoring of the discharges which have long pulse lengths, of the order of minutes. (Author)

  16. Modelling and analysis of flux surface mapping experiments on W7-X

    Science.gov (United States)

    Lazerson, Samuel; Otte, Matthias; Bozhenkov, Sergey; Sunn Pedersen, Thomas; Bräuer, Torsten; Gates, David; Neilson, Hutch; W7-X Team

    2015-11-01

    The measurement and compensation of error fields in W7-X will be key to the device achieving high beta steady state operations. Flux surface mapping utilizes the vacuum magnetic flux surfaces, a feature unique to stellarators and heliotrons, to allow direct measurement of magnetic topology, and thereby allows a highly accurate determination of remnant magnetic field errors. As will be reported separately at this meeting, the first measurements confirming the existence of nested flux surfaces in W7-X have been made. In this presentation, a synthetic diagnostic for the flux surface mapping diagnostic is presented. It utilizes Poincaré traces to construct an image of the flux surface consistent with the measured camera geometry, fluorescent rod sweep plane, and emitter beam position. Forward modeling of the high-iota configuration will be presented demonstrating an ability to measure the intrinsic error field using the U.S. supplied trim coil system on W7-X, and a first experimental assessment of error fields in W7-X will be presented. This work has been authored by Princeton University under Contract Number DE-AC02-09CH11466 with the US Department of Energy.

  17. Designs of Langmuir probes for W7-X

    International Nuclear Information System (INIS)

    Laube, Ralph; Laux, Michael; Ye, Min You; Greuner, Henri; Lindig, Stefan

    2011-01-01

    Several designs of Langmuir probes for the stellarator Wendelstein 7-X (W7-X) are described. Different types of probes are proposed for the different divertors to be used during different operational phases of W7-X. Comb-like arrays of stiff probes, arrays of flexible probes, and fixed inlay probes are reviewed. For the initial phase of W7-X it was decided to install arrays of fixed inlay probes. Two mockups were manufactured and one of them was tested with success in the high heat flux test facility GLADIS. For long-pulse operation of W7-X different conceptual designs are proposed and are still developed further. This paper summarizes the different design constrains for the Langmuir probes in the different divertor surroundings, describes the design of the array of inlay probes for the initial phase and the result of the GLADIS test, and gives a preview of the conceptual designs of probes for the long-pulse operational phase of W7-X.

  18. Thermo-mechanical tests on W7-X current lead flanges

    International Nuclear Information System (INIS)

    Dhard, Chandra Prakash; Rummel, Thomas; Zacharias, Daniel; Bykov, Victor; Moennich, Thomas; Buscher, Klaus-Peter

    2013-01-01

    Highlights: • There are significant mechanical loads on the cryostat and radial flanges for W7-X current leads. • These are due to evacuation of W7-X cryostat, cool-down of cold mass, electro-magnetic forces and self weight of leads. • The actual mechanical loads were reduced to simplify the experimental set-up. • The tests were carried out on mock-up flanges test assembly at ambient temperature and at 77 K. • The thermo-mechanical tests on W7-X current lead flanges validate the design and joints of these flanges to the leads. -- Abstract: Fourteen pieces of high temperature superconducting current leads (CL) arranged in seven pairs, will be installed on the outer vessel of Wendelstein 7-X (W7-X) stellarator. In order to support the CL, it is provided with two glass fiber reinforce plastic (GFRP) flanges, namely, the lower cryostat flange (CF) remaining at room temperature and upper radial flange (RF) at about 5 K. Both the flanges i.e. CF and RF experience high mechanical loads with respect to the CL, due to the evacuation of W7-X cryostat, cool-down of cold mass including the CL, electro-magnetic forces due to current and plasma operations and self weight of CL. In order to check the integrity of these flanges for such mechanical loads, thermo-mechanical tests were carried out on these flanges at room temperatures and at liquid nitrogen (LN2) temperatures. The details of test set-up, results and modeling are described in the paper

  19. Superconducting Coil of Po Dipole

    CERN Multimedia

    1983-01-01

    The Po superconducting dipole was built as a prototype beam transport magnet for the SPS extracted proton beam P0. Its main features were: coil aperture 72 mm, length 5 m, room-temperature yoke, NbTi cable conductor impregnated with solder, nominal field 4.2 T at 4.7 K (87% of critical field). It reached its nominal field without any quench.After this successful test up to its nominal field of 4.2 T, the power was not raised to reach a quench. The magnet was not installed in a beam and had no other further use. Nevertheless its construction provided knowledges and experience which became useful in the design and construction of the LHC magnets. The photo shows a detail of the inner layer winding before superposing the outer layer to form the complete coil of a pole. Worth noticing is the interleaved glass-epoxy sheet (white) with grooved channels for the flow of cooling helium. See also 8211532X.

  20. Design criteria of the bolometer diagnostic for steady-state operation of the W7-X stellaratora

    NARCIS (Netherlands)

    Zhang, D.; Burhenn, R.; König, R.; Giannone, L.; Grodzki, P.A.; Klein, B.; Grosser, K.; Baldzuhn, J.; Ewert, K.; Erckmann, V.; Hirsch, M.; Laqua, H.P.; Oosterbeek, J.W.

    2010-01-01

    A bolometric diagnostic system with features necessary for steady-state operation in the superconducting stellarator W7-X was designed. During a pulse length of 1800 s with an ECRH (electron cyclotron resonance heating) power of 10 MW, the components suffer not only from a large thermal load but

  1. High-field superconducting nested coil magnet

    Science.gov (United States)

    Laverick, C.; Lobell, G. M.

    1970-01-01

    Superconducting magnet, employed in conjunction with five types of superconducting cables in a nested solenoid configuration, produces total, central magnetic field strengths approaching 70 kG. The multiple coils permit maximum information on cable characteristics to be gathered from one test.

  2. Design criteria of the bolometer diagnostic for steady-state operation of the W7-X stellarator

    International Nuclear Information System (INIS)

    Zhang, D.; Burhenn, R.; Koenig, R.; Giannone, L.; Grodzki, P. A.; Klein, B.; Grosser, K.; Baldzuhn, J.; Ewert, K.; Erckmann, V.; Hirsch, M.; Laqua, H. P.; Oosterbeek, J. W.

    2010-01-01

    A bolometric diagnostic system with features necessary for steady-state operation in the superconducting stellarator W7-X was designed. During a pulse length of 1800 s with an ECRH (electron cyclotron resonance heating) power of 10 MW, the components suffer not only from a large thermal load but also from stray radiation of the nonabsorbed isotropic microwaves. This paper gives an overview of the technical problems encountered during the design work and the solutions to individual problems to meet the special requirements in W7-X, e.g., component thermal protection, detector offset thermal drift suppression, as well as a microwave shielding technique.

  3. Design criteria of the bolometer diagnostic for steady-state operation of the W7-X stellaratora)

    Science.gov (United States)

    Zhang, D.; Burhenn, R.; Koenig, R.; Giannone, L.; Grodzki, P. A.; Klein, B.; Grosser, K.; Baldzuhn, J.; Ewert, K.; Erckmann, V.; Hirsch, M.; Laqua, H. P.; Oosterbeek, J. W.

    2010-10-01

    A bolometric diagnostic system with features necessary for steady-state operation in the superconducting stellarator W7-X was designed. During a pulse length of 1800 s with an ECRH (electron cyclotron resonance heating) power of 10 MW, the components suffer not only from a large thermal load but also from stray radiation of the nonabsorbed isotropic microwaves. This paper gives an overview of the technical problems encountered during the design work and the solutions to individual problems to meet the special requirements in W7-X, e.g., component thermal protection, detector offset thermal drift suppression, as well as a microwave shielding technique.

  4. Superconducting coil development and motor demonstration: Overview

    Science.gov (United States)

    Gubser, D. U.

    1995-12-01

    Superconducting bismuth-cuprate wires, coils, and magnets are being produced by industry as part of a program to test the viability of using such magnets in Naval systems. Tests of prototype magnets, coils, and wires reveal progress in commercially produced products. The larger magnets will be installed in an existing superconducting homopolar motor and operated initially at 4.2K to test the performance. It is anticipated that approximately 400 Hp will be achieved by the motor. This article reports on the initial tests of the magnets, coils, and wires as well as the development program to improve their performance.

  5. Database structures and interfaces for W7-X

    International Nuclear Information System (INIS)

    Heimann, P.; Bluhm, T.; Hennig, Ch.; Kroiss, H.; Kuehner, G.; Maier, J.; Riemann, H.; Zilker, M.

    2008-01-01

    The W7-X experiment of the IPP, under construction in Greifswald Germany, is designed to operate in a quasi-steady-state scenario. The database structures and interfaces used for discharge description and execution have to reflect this continuous mode of operation. In close collaboration between the control group of W7-X and the data acquisition group a combined design of the data structures used for describing the configuration and the operation of the experiment was developed. To guarantee access to this information from all participating stations a TCP/IP portal and a proxy server were developed. This portal enables especially the VxWorks real-time operating systems of the control stations to access the information in the object-oriented database. The database schema includes now a more functional description of the experiment and gives the physicists a more simplified view of the necessary definitions of operational parameters. The scheduling of the long discharges of W7-X will be done by predefining operational parameters in segments and scenarios, where a scenario is a fixed sequence of segments with a common physical background. To hide the specialized information contained in the basic parameters from the experiment leader or physicist an abstraction layer was introduced that only shows physically interesting information. An executable segment will be generated after verifying the consistency of the high-level parameters by using a transformation function for every basic parameter needed. Since the database contains all configurations and discharge definitions necessary to operate the experiment, it is very important to give the user a tool to manipulate this information in an intuitive way. A special editor (ConfiX) was designed and implemented for this task. At the moment the basic functionality for dealing with all kind of objects in the database is available. Future releases will extend the functionality to defining and editing configurations, segments

  6. ECRH and ECCD scenarios for W7-X

    Directory of Open Access Journals (Sweden)

    Laqua H.P.

    2012-09-01

    Full Text Available The main ECRH scenarios for the W7-X Stellarator are described. Both X2 (low and moderate densities and O2 scenarios (high density have been studied. Since O2 scenario cannot be realized without pre-heating, transition from X2 to O2 scenarios has been discussed. Due to a lack of Ohmic transformer, only ECCD is available for compensating the bootstrap current and for controlling the edge rotational transform value. The efficiency of ECCD for all main scenarios has been estimated. All simulations have been performed by a 1D transport code coupled self-consistently with ray-tracing code.

  7. ANL experimental program for pulsed superconducting coils

    International Nuclear Information System (INIS)

    Wang, S.T.; Kim, S.H.; Praeg, W.F.; Krieger, C.I.

    1978-01-01

    Argonne National Laboratory (ANL) had recognized the clear advantage of a superconducting ohmic-heating (OH) coil and started in aggressive development program in FY 1977. The main objectives for FY 1977 are to develop cryostable basic cable configurations with reasonably low ac losses, to develop 12 kA cryostable cable, using it to design and build a 1.5 MJ pulsed coil, and to develop a rather inexpensive large fiberglass reinforced helium cryostat for the 1.5 MJ pulsed coil. The principal objective in building the 1.5 MJ ac coil is to demonstrate ac cryostability of a large coil ranging from 2 T/s up to 12 T/s. Another objective in the pulsed coil program is to determine the feasibility of parallel coil operation in order to avoid excessive voltage and current requirements and to minimize the number of turns for the equilibrium field (EF) coils, should the EF coils be connected in parallel with the OH coils. A two-coil section model using the 11 kA cable will be built and tested

  8. ANL experimental program for pulsed superconducting coils

    International Nuclear Information System (INIS)

    Wang, S.T.; Kim, S.H.; Praeg, W.F.; Krieger, C.I.

    1977-01-01

    Argonne National Laboratory (ANL) had recognized the clear advantage of a superconducting ohmic-heating (OH) coil and started an aggressive development program in FY 1977. The main objectives for FY 1977 are to develop cryostable basic cable configurations with reasonably low ac losses, to develop 12 kA cryostable cable, using it to design and build a 1.5 MJ pulsed coil, and to develop a rather inexpensive large fiberglass reinforced helium cryostat for the 1.5 MJ pulsed coil. The principal objective in building the 1.5 MJ ac coil is to demonstrate ac cryostability of a large coil ranging from 2 T/s up to 12 T/s. Another objective in the pusled coil program is to determine the feasibility of parallel coil operation in order to avoid excessive voltage and current requirements and to minimize the number of turns for the equilibrium field (EF) coils, should the EF coils be connected in parallel with the OH coils. A two-coil section model using the 11 kA cable will be built and tested

  9. Argonne National Laboratory superconducting pulsed coil program

    International Nuclear Information System (INIS)

    Wang, S.T.; Kim, S.H.

    1979-01-01

    The main objectives are to develop high current (approx. 100 kA) cryostable cable configurations with reasonably low ac losses, to build a demonstration pulsed coil, and to develop a rather inexpensive large fiberglass reinforced helium cryostat. A 1.5-MJ cryostable pulsed superconducting coil has been developed and constructed at ANL. The coil has a peak field of 4.5 T at an operating current of 11.0 kA. A large inexpensive plastic cryostat has been developed for testing the pulsed coil. The coil has been pulsed with a maximum dB/dt of 11 T/s. The coil was pulsed more than 4000 cycles. Detailed results of the ac loss measurements and the current sharing of the cryostability will be described

  10. Winding machines for the manufacturing of superconductive coils of the main European fusion research machines

    CERN Document Server

    Cazzaniga, R; D’Urzo, C

    2005-01-01

    The successfull construction of large magnets passes through the development and application of non-conventional manufacturing processes. A difficult and delicate step in the manufacturing of superconducting coils is the conductor winding technique. It is often a challenging and technologically advanced process, developed according to the requirements of each project. An important aspect during the winding is to avoid any deformation of the cable cross section leading to a damage of the strands and to maintain the design features of the cable. A second aspect is to assure the suitable repeatability and a production rate for an industrial process. The winding line is a system of different machines linked and tuned together properly designed for each project. An adapted software assures the overall process control. TPA realized for ANSALDO Superconduttori the winding lines for many projects: TFMC (NET-TEAM), CMS (INFN-CERN), WENDELSTEIN W7-X (Max Planck Institute, IPP), etc. The experience acquired in this fiel...

  11. User Control Interface for W7-X Plasma Operation

    International Nuclear Information System (INIS)

    Spring, A.; Laqua, H.; Schacht, J.

    2006-01-01

    The WENDELSTEIN 7-X fusion experiment will be a highly complex device operated by a likewise complex control system. The fundamental configuration of the W7-X control system follows two major design principles: It reflects the strict hierarchy of the machine set-up with a set of subordinated components, which in turn can be run autonomously during commissioning and testing. Secondly, it links the basic machine operation (mainly given by the infrastructure status and the components readiness) and the physics program execution (i.e. plasma operation) on each hierarchy level and on different time scales. The complexity of the control system implies great demands on appropriate user interfaces: specialized tools for specific control tasks allowing a dedicated view on the subject to be controlled, hiding complexity wherever possible and reasonable, providing similar operation methods on each hierarchy level and both manual interaction possibilities and a high degree of intelligent automation. The contribution will describe the operation interface for experiment control including the necessary links to the machine operation. The users of ' Xcontrol ' will be both the W7-X session leaders during plasma discharge experiments and the components' or diagnostics' operators during autonomous mode or even laboratory experiments. The main ' Xcontrol ' features, such as program composition and validation, manual and automatic control instruments, resource survey, and process monitoring, will be presented. The implementation principles and the underlying communication will be discussed. (author)

  12. Internal trim coils for CBA superconducting magnets

    International Nuclear Information System (INIS)

    Thompson, P.A.; Aronson, S.; Cottingham, J.G.; Garber, M.; Hahn, H.; Sampson, W.B.

    1983-01-01

    In order to correct iron saturation effects and shape the beam working line, superconducting trim coils have been constructed, which operate inside the main coils. Detailed studies of mechanical properties, quench behavior, fields produced, and hysteresis have lead to the production of accelerator-quality coils generating the required-strength harmonics up to cos (7theta). These are routinely installed in CBA main magnets and operate at 80% of short sample with negligible training in an ambient field of more than 5.3T

  13. Experiment planning using high-level component models at W7-X

    International Nuclear Information System (INIS)

    Lewerentz, Marc; Spring, Anett; Bluhm, Torsten; Heimann, Peter; Hennig, Christine; Kühner, Georg; Kroiss, Hugo; Krom, Johannes G.; Laqua, Heike; Maier, Josef; Riemann, Heike; Schacht, Jörg; Werner, Andreas; Zilker, Manfred

    2012-01-01

    Highlights: ► Introduction of models for an abstract description of fusion experiments. ► Component models support creating feasible experiment programs at planning time. ► Component models contain knowledge about physical and technical constraints. ► Generated views on models allow to present crucial information. - Abstract: The superconducting stellarator Wendelstein 7-X (W7-X) is a fusion device, which is capable of steady state operation. Furthermore W7-X is a very complex technical system. To cope with these requirements a modular and strongly hierarchical component-based control and data acquisition system has been designed. The behavior of W7-X is characterized by thousands of technical parameters of the participating components. The intended sequential change of those parameters during an experiment is defined in an experiment program. Planning such an experiment program is a crucial and complex task. To reduce the complexity an abstract, more physics-oriented high-level layer has been introduced earlier. The so-called high-level (physics) parameters are used to encapsulate technical details. This contribution will focus on the extension of this layer to a high-level component model. It completely describes the behavior of a component for a certain period of time. It allows not only defining simple value ranges but also complex dependencies between physics parameters. This can be: dependencies within components, dependencies between components or temporal dependencies. Component models can now be analyzed to generate various views of an experiment. A first implementation of such an analyze process is already finished. A graphical preview of a planned discharge can be generated from a chronological sequence of component models. This allows physicists to survey complex planned experiment programs at a glance.

  14. Energetic Particle Loss Estimates in W7-X

    Science.gov (United States)

    Lazerson, Samuel; Akaslompolo, Simppa; Drevlak, Micheal; Wolf, Robert; Darrow, Douglass; Gates, David; W7-X Team

    2017-10-01

    The collisionless loss of high energy H+ and D+ ions in the W7-X device are examined using the BEAMS3D code. Simulations of collisionless losses are performed for a large ensemble of particles distributed over various flux surfaces. A clear loss cone of particles is present in the distribution for all particles. These simulations are compared against slowing down simulations in which electron impact, ion impact, and pitch angle scattering are considered. Full device simulations allow tracing of particle trajectories to the first wall components. These simulations provide estimates for placement of a novel set of energetic particle detectors. Recent performance upgrades to the code are allowing simulations with > 1000 processors providing high fidelity simulations. Speedup and future works are discussed. DE-AC02-09CH11466.

  15. Simulation of neutron fluxes around the W7-X Stellarator

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Jenny

    1999-12-01

    A new fusion experiment, the WENDELSTEIN 7-X Stellarator (W7-X), will be undertaken in Greifswald in Germany. Measurements of the neutron flux will provide information on fusion reaction rates and possibly also on ion temperatures as function of time. For this purpose moderating neutron counters will be designed, tested, calibrated and eventually used at W7-X. Extensive Monte-Carlo simulations have been performed in order to select the most suitable detector and moderator combination with a flat response function and highest achievable efficiency. Different detector configurations with different moderating materials have been tried out, showing that a 32 cm thick graphite moderating BF{sub 3} -counter gives the desired flat response and sufficient efficiency. Neutron spectra calculations have been made for different torus models and the influence of floor, walls and ceiling (i.e. reactor hall) have been investigated. Presented results suggest that a more detailed torus model significantly reduces the number of neutron counts at the detector. Calculations including the reactor hall indicate a tendency of shifting the neutron spectra towards the thermal region. The main part of the scattered neutrons are back-scattered from the floor. Finally, calculations on the graphite moderating BF{sub 3} -counter in the detailed torus environment were performed in order to assess the absolute response function under the influence of the reactor hall. The results show that the detector count rate will increase by only 5-7 % when the reactor hall is taken into account. With a stellarator generating 10{sup 12} to 10{sup 16} neutrons per second the detector count rate will be 2x10{sup 5} to 2x10{sup 9} neutrons per second.

  16. Employing industrial standards in software engineering for W7X

    Energy Technology Data Exchange (ETDEWEB)

    Kuehner, Georg [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Teilinstitut Greifswald, Wendelsteinstrasse 1, D-17491 Greifswald (Germany)], E-mail: kuehner@ipp.mpg.de; Bluhm, Torsten [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Teilinstitut Greifswald, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Heimann, Peter [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, D-85748 Garching (Germany); Hennig, Christine [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Teilinstitut Greifswald, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Kroiss, Hugo [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, D-85748 Garching (Germany); Krueger, Alexander [University of Applied Sciences, Schwedenschanze 135, 18435 Stralsund (Germany); Laqua, Heike; Lewerentz, Marc [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Teilinstitut Greifswald, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Maier, Josef [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, D-85748 Garching (Germany); Riemann, Heike; Schacht, Joerg; Spring, Anett; Werner, Andreas [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Teilinstitut Greifswald, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Zilker, Manfred [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, D-85748 Garching (Germany)

    2009-06-15

    The stellarator W7X is a large complex experiment designed for continuous operation and planned to be operated for about 20 years. Software support is highly demanded for experiment preparation, operation and data analysis which in turn induces serious non-functional requirements on the software quality like, e.g.: {center_dot}high availability, stability, maintainability vs. {center_dot}high flexibility concerning change of functionality, technology, personnel {center_dot}high versatility concerning the scale of system size and performance These challenges are best met by exploiting industrial experience in quality management and assurance (QM/QA), e.g. focusing on top-down development methods, developing an integral functional system model, using UML as a diagramming standard, building vertical prototypes, support for distributed development, etc., which have been used for W7X, however on an 'as necessary' basis. Proceeding in this manner gave significant results for control, data acquisition, corresponding database-structures and user applications over many years. As soon as production systems started using the software in the labs or on a prototype the development activity demanded to be organized in a more rigorous process mainly to provide stable operation conditions. Thus a process improvement activity was started for stepwise introduction of quality assuring processes with tool support taking standards like CMMI, ISO-15504 (SPICE) as a guideline. Experiences obtained so far will be reported. We conclude software engineering and quality assurance has to be an integral part of systems engineering right from the beginning of projects and be organized according to industrial standards to be prepared for the challenges of nuclear fusion research.

  17. Simulation of neutron fluxes around the W7-X Stellarator

    International Nuclear Information System (INIS)

    Andersson, Jenny

    1999-12-01

    A new fusion experiment, the WENDELSTEIN 7-X Stellarator (W7-X), will be undertaken in Greifswald in Germany. Measurements of the neutron flux will provide information on fusion reaction rates and possibly also on ion temperatures as function of time. For this purpose moderating neutron counters will be designed, tested, calibrated and eventually used at W7-X. Extensive Monte-Carlo simulations have been performed in order to select the most suitable detector and moderator combination with a flat response function and highest achievable efficiency. Different detector configurations with different moderating materials have been tried out, showing that a 32 cm thick graphite moderating BF 3 -counter gives the desired flat response and sufficient efficiency. Neutron spectra calculations have been made for different torus models and the influence of floor, walls and ceiling (i.e. reactor hall) have been investigated. Presented results suggest that a more detailed torus model significantly reduces the number of neutron counts at the detector. Calculations including the reactor hall indicate a tendency of shifting the neutron spectra towards the thermal region. The main part of the scattered neutrons are back-scattered from the floor. Finally, calculations on the graphite moderating BF 3 -counter in the detailed torus environment were performed in order to assess the absolute response function under the influence of the reactor hall. The results show that the detector count rate will increase by only 5-7 % when the reactor hall is taken into account. With a stellarator generating 10 12 to 10 16 neutrons per second the detector count rate will be 2x10 5 to 2x10 9 neutrons per second

  18. Blower Gun pellet injection system for W7-X

    Energy Technology Data Exchange (ETDEWEB)

    Dibon, M., E-mail: mathias.dibon@ipp.mpg.de [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Baldzuhn, J.; Beck, M. [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Cardella, A. [Lehrstuhl für Nukleartechnik, TU Munich, Boltzmannstr. 15, 85748 Garching (Germany); Köchl, F. [Atominstitut, TU Wien, 1020 Vienna (Austria); Kocsis, G. [Wigner RCP, RMI, P.O. Box 49, H-1525 Budapest-114 (Hungary); Lang, P.T. [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Macian-Juan, R. [Lehrstuhl für Nukleartechnik, TU Munich, Boltzmannstr. 15, 85748 Garching (Germany); Ploeckl, B. [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Szepesi, T. [Wigner RCP, RMI, P.O. Box 49, H-1525 Budapest-114 (Hungary); Weisbart, W. [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany)

    2015-10-15

    Highlights: • Operational principle of the ASDEX Upgrade Blower Gun. • Guiding tube properties for pellet guiding according to the requirements of W7-X. • Diagnostics for the characterization of the injection system. • Experimental procedure to investigate the performance of the Blower Gun. • Results concerning pellet speeds, mass loss, delivery efficiency and exit angle. - Abstract: Foreseen to perform pellet investigations in the new stellarator W7-X, the former ASDEX Upgrade Blower Gun was revised and revitalized. The systems operational characteristics have been surveyed in a test bed. The gun is designed to launch cylindrical pellets with 2 mm diameter and 2 mm length, produced from frozen deuterium D{sub 2}, hydrogen H{sub 2} or a gas mixture consisting of 50% H{sub 2} and 50% D{sub 2}. Pellets are accelerated by a short pulse of pressurized helium propellant gas to velocities in the range of 100–250 m/s. Delivery reliabilities at the launcher exit reach almost unity. The initial pellet mass is reduced to about 50% during the acceleration process. Pellet transfer to the plasma vessel was investigated by a first mock up guiding tube version. Transfer through this S-shaped stainless steel guiding tube (inner diameter 8 mm; length 6 m) containing two 1 m curvature radii was investigated for all pellet types. Tests were performed applying repetition rates from 2 Hz to 50 Hz and propellant gas pressures ranging from 0.1 to 0.6 MPa. For both H{sub 2} and D{sub 2}, low overall delivery efficiencies were observed at slow repetition rates, but stable efficiencies of about 90% above 10 Hz. About 10% of the mass is eroded while flying through the guiding tube. Pellets exit the guiding tube with an angular spread of less than 14°.

  19. Progress on large superconducting toroidal field coils

    International Nuclear Information System (INIS)

    Haubenreich, P.N.; Luton, J.N.; Thompson, P.B.; Beard, D.S.

    1979-01-01

    Large superconducting toroidal field coils of competing designs are being produced by six major industrial teams. In the US, teams headed by General Dynamics Convair, General Electric, and Westinghouse are under contract to design and fabricate one coil each to specifications established by the Large Coil Program. A facility for testing 6 coils in a toroidal array at fields to 8 to 12 tesla is under construction at Oak Ridge. Through an international agreement, EURATOM, Japan, and Switzerland will produce one coil each for testing with the US coils. Each test coil will have a 2.5 x 3.5 m D-shape winding bore and is designed to operate at a current of 10 to 18 kA at a peak field of 8T while subjected to pulsed fields of 0.14 T applied in 1.0 s. There are significant differences among the six coil designs: five use NbTi, one Nb 3 Sn; three are cooled by pool boiling helium, three by forced flow; five have welded or bolted stainless steel coil cases, one has aluminum plate structure. All are designed to be cryostable at 8T, with structural margin for extended operation. The three US coil teams are almost or completely finished with detailed design and are now procuring materials and setting up manufacturing equipment. The non-US teams are at various stages of verification testing and design. The GDC and GE coils are scheduled for delivery in the spring of 1981 and the others will be completed a year later. The 11-m diameter vessel at the test facility has been completed and major components of the test stand are being procured. Engineering and procurement to upgrade the helium liquifier-refrigerator system are under way

  20. Current control by ECCD for W7-X

    International Nuclear Information System (INIS)

    Turkin, Yu.; Maassberg, H.; Beidler, C.D.; Geiger, J.; Marushchenko, N.B.

    2005-01-01

    One of the optimization criteria for the stellarator W7-X is the minimization of the bootstrap current. The plasma current changes the magnetic configuration, especially near the plasma edge, where X-points and islands are located. It was shown that the plasma parameter distributions in the divertor region and the particle and energy depositions on the divertor plates depend strongly on the island geometry. An estimation of the tolerable plasma current obtained from the shift of the island structure close to the target plates shows that the plasma current should be controlled within a range of about 10 kA. The bootstrap current even for the standard configuration can easily exceed this value. The W7-X is not equipped with an Ohmic transformer, so the only means for compensating this current is electron cyclotron current drive (ECCD) and/or neutral beam current drive (NBCD). In this report we study the compensation of residual bootstrap current by using ECCD. To model the control of the toroidal current we use a predictive 1D transport code, which is under development. For evaluation of the bootstrap current and neoclassical transport coefficients we use results from an international collaboration on neoclassical transport in stellarators. Power deposition and current drive profiles due to electron cyclotron resonance heating are calculated by a new ray tracing code. The modeling showed that the loop voltage induced by ECCD leads to a redistribution of the current density with the diffusion time of about two seconds. The relaxation time of the total current is much longer than this time - for a typical ECRH-plasma the total toroidal current reaches steady state after several L/R-time that is about hundreds of seconds. In order to keep current in an acceptable range and to avoid long relaxation times we propose Feed-forward or Predictive control using ECCD as actuator, the steps are as follows: - calculate the bootstrap current distribution using measured plasma

  1. Switching transients in a superconducting coil

    International Nuclear Information System (INIS)

    Owen, E.W.; Shimer, D.W.

    1983-01-01

    A study is made of the transients caused by the fast dump of large superconducting coils. Theoretical analysis, computer simulation, and actual measurements are used. Theoretical analysis can only be applied to the simplest of models. In the computer simulations two models are used, one in which the coil is divided into ten segments and another in which a single coil is employed. The circuit breaker that interrupts the current to the power supply, causing a fast dump, is represented by a time and current dependent conductance. Actual measurements are limited to measurements made incidental to performance tests on the MFTF Yin-yang coils. It is found that the breaker opening time is the critical factor in determining the size and shape of the transient. Instantaneous opening of the breaker causes a lightly damped transient with large amplitude voltages to ground. Increasing the opening time causes the transient to become a monopulse of decreasing amplitude. The voltages at the external terminals are determined by the parameters of the external circuit. For fast opening times the frequency depends on the dump resistor inductance, the circuit capacitance, and the amplitude on the coil current. For slower openings the dump resistor inductance and the current determine the amplitude of the voltage to ground at the terminals. Voltages to ground are less in the interior of the coil, where transients related to the parameters of the coil itself are observed

  2. Superconducting Coil Winding Machine Control System

    Energy Technology Data Exchange (ETDEWEB)

    Nogiec, J. M. [Fermilab; Kotelnikov, S. [Fermilab; Makulski, A. [Fermilab; Walbridge, D. [Fermilab; Trombly-Freytag, K. [Fermilab

    2016-10-05

    The Spirex coil winding machine is used at Fermilab to build coils for superconducting magnets. Recently this ma-chine was equipped with a new control system, which al-lows operation from both a computer and a portable remote control unit. This control system is distributed between three layers, implemented on a PC, real-time target, and FPGA, providing respectively HMI, operational logic and direct controls. The system controls motion of all mechan-ical components and regulates the cable tension. Safety is ensured by a failsafe, redundant system.

  3. Preparing diagnostics for long pulse operation at W7-X

    Energy Technology Data Exchange (ETDEWEB)

    Neuner, Ulrich, E-mail: u.neuner@ipp.mpg.de [Max-Planck-Institut fuer Plasmaphysik EURATOM Association, Greifswald (Germany); Brucker, Bertram [Max-Planck-Institut fuer Plasmaphysik EURATOM Association, Greifswald (Germany); Cardella, Antonio [European Commision c/o W7-X, Max-Planck-Institut fuer Plasmaphysik EURATOM Association, Greifswald (Germany); Endler, Michael; Grosser, Klaus; Hathiramani, Dag; Hirsch, Matthias; Koenig, Ralf; Pasch, Ekkehard; Pilopp, Dirk; Schuelke, Matthias; Thiel, Stefan; Thomsen, Henning; Wolf, Robert; Zhang Daihong [Max-Planck-Institut fuer Plasmaphysik EURATOM Association, Greifswald (Germany)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer In long pulse fusion devices diagnostics are subject to severe heating. Black-Right-Pointing-Pointer Several concepts to reduce the heat influx were applied. Black-Right-Pointing-Pointer Heat conduction was improved to keep the temperature within acceptable limits. - Abstracts: Long pulse operation considerably increases the thermal load on in-vessel components. Diagnostic front-ends formerly employed at short pulse machines therefore have to be considerably re-designed for installation in the stellarator W7-X that is currently being built at Greifswald, Germany. The strategy applied to cope with the thermal load is threefold: to reduce the influx of heat on the component, to conduct the heat inside the component to suitable heat sinks and to choose suitable materials for sensitive components. The first is achieved by the shielding against microwave stray radiation, plasma radiation, thermal radiation and particle fluxes and by absorbing residual microwave stray radiation in the immediate vicinity of sensitive components. The second task, suitable heat conduction, enforces severe restrictions on the use of any thin parts like foils or meshes. Thirdly, in order for a component to survive the residual loads, materials must be chosen that absorb only a small fraction of the microwave stray radiation flux, conduct heat well enough, and survive high temperatures and large temperature gradients. Examples are provided from bolometry, magnetic diagnostics, soft X-ray diagnostics and Thomson scattering. Measurements of microwave stray radiation effects are presented, in particular the effectiveness of several shielding concepts.

  4. General Atomic's superconducting toroidal field coil concept

    International Nuclear Information System (INIS)

    Alcorn, J.; Purcell, J.

    1978-01-01

    General Atomic's concept for a superconducting toroidal field coil is presented. The concept is generic for large tokamak devices, while a specific design is indicated for a 3.8 meter (major radius) ignition/burn machine. The concept utilizes bath cooled NbTi conductor to generate a peak field of 10 tesla at 4.2 K. The design is simple and straightforward, requires a minimum of developmental effort, and draws extensively upon the perspective of past experience in the design and construction of large superconducting magnets for high energy physics. Thus, the primary emphasis is upon economy, reliability, and expeditious construction scheduling. (author)

  5. Mechanical study of 20 MJ superconducting pulse coil

    International Nuclear Information System (INIS)

    Hattori, Yasuhide; Shimamoto, Susumu

    1985-09-01

    This paper describes calculation methods and computer codes of stress distribution in a circular-shaped superconducting pulsed coils. The stress problems of a large sized superconducting coil, for example, are discussed for 20 MJ pool-cooled pulse coil. Young's modulus of a stranded flat cable, low rigidity, is measured and evaluated. (author)

  6. Study of neoclassical transport and bootstrap current for W7-X in the 1/upsilon regime, using results from the PIES code

    International Nuclear Information System (INIS)

    Nemov, V V; Kalyuzhnyj, V N; Kasilov, S V; Drevlak, M; Nuehrenberg, J; Kernbichler, W; Reiman, A; Monticello, D

    2004-01-01

    For the magnetic field of the Wendelstein 7-X (W7-X) standard high-mirror configuration, computed by the PIES code, taking into account real coil geometry, neoclassical transport and bootstrap current are analysed in the 1/upsilon regime using methods based on the integration along magnetic field lines in a given magnetic field. The zero beta and (beta) = 1% cases are studied. The results are compared to the corresponding results for the vacuum magnetic field directly produced by modular coils. A significant advantage of W7-X over a conventional stellarator resulting from reduced neoclassical transport and from reduced bootstrap current follows from the computations although the neoclassical transport is somewhat larger than that previously obtained for the ideal W7-X model configuration

  7. Effects of insulation on potted superconducting coils

    International Nuclear Information System (INIS)

    Zeller, A.F.; DeKamp, J.C.; Magsig, C.T.; Nolen, J.A.; McInturff, A.D.

    1989-01-01

    Test coils using identical wire but with either Formvar or Polyesterimid insulation were fabricated to determine the effects of insulation on training behavior. It was found that the type of insulation did not affect the training behavior. While considerable attention has been paid to epoxy formulations used for superconducting coils, little study has been devoted to the effects of the wire insulation on training behavior. If the insulation does not bind well with the epoxy, the wires will not be held securely in place, and training will be required to make the coil operate at its design limit. In fact, the coil may never reach its design current, showing considerable degredation. Conversely, if the epoxy-insulation reaction is to soften or weaken the insulation, then shorts and/or training may result. The authors have undertaken a study of the effects of the insulation on potted coils wet wound with Stycast 2850 FT epoxy. The wire was insulated with one of two insulting varnishes: Formvar (a polyvinyl formal resin) or Polyesterimid (a phenolic resin). Formvar is the standard insulation in the United States while Polyesterimid the European standard

  8. Structural design of the superconducting toroidal field coils for ITER

    International Nuclear Information System (INIS)

    Wong, F.M.G.; Sborchia, C.; Thome, R.J.; Malkov, A.; Titus, P.H.

    1995-01-01

    Structural design issues and features of the superconducting toroidal field (TF) coils for the International Thermonuclear Experimental Reactor (ITER) will be discussed. Selected analyses of the structural and mechanical behavior of the ITER TF coils will also be presented. (orig.)

  9. Statistical analysis of the equilibrium configurations of the W7-X stellarator using function parameterization

    International Nuclear Information System (INIS)

    Mc Carthy, P.J.; Sengupta, A.; Geiger, J.; Werner, A.

    2005-01-01

    The W7-X stellarator, under construction at IPP-Greifswald, is being designed to demonstrate the steady state capability of fusion devices. Due to the pulse length involved, real time monitoring and control of the discharges is a crucial issue in steady state operations. For W7-X, we have planned a sequence of in-depth analyses of the magnetic configurations which, ultimately, will lead to a proper understanding of plasma equilibrium, stability and transport. It should also provide insight into the parameterization of the various plasma-related quantities which is important from the point of view of real time study. The first step in our sequence of analyses involved a study of the vacuum configuration, including the detectable magnetic islands, of W7-X. We now proceed to the scenario at finite beta considering full magnetohydrodynamic (MHD) equilibria based on vmec2000 calculations. A database of order 10000 equilibria was calculated on the same parameter space for the coil current ratios. The parameters which were varied randomly and independently consist of the external coil current ratios (6), the parameters of the profiles (as functions of normalised toroidal flux) of plasma pressure and toroidal current (4+4) and the plasma size (a eff ) which is required to vary the plasma volume. A statistical analysis, using Function Parametrization (FP), was performed on a sample of well-converged equilibria. The plasma parameters were varied to allow a good FP for the expected values in W7-X, i.e. volume-averaged up to 5% and toroidal net-current of up to ±50 kA for a mean field strength of about 2 T throughout the database. The profiles were chosen as a sequence of polynomials with the property that the addition of a higher order polynomial would not change the lower order volume-averaged moments of the resulting profile. The aim of this was to try to avoid cross correlations in the independent input parameters for the database generation. However, some restrictions

  10. Superconducting coil and method of stress management in a superconducting coil

    Science.gov (United States)

    McIntyre, Peter M.; Shen, Weijun; Diaczenko, Nick; Gross, Dan A.

    1999-01-01

    A superconducting coil (12) having a plurality of superconducting layers (18) is provided. Each superconducting layer (18) may have at least one superconducting element (20) which produces an operational load. An outer support structure (24) may be disposed outwardly from the plurality of layers (18). A load transfer system (22) may be coupled between at least one of the superconducting elements (20) and the outer support structure (24). The load transfer system (22) may include a support matrix structure (30) operable to transfer the operational load from the superconducting element (20) directly to the outer support structure (24). A shear release layer (40) may be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a shear stress between the superconducting element (20) and the support matrix structure (30). A compliant layer (42) may also be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a compressive stress on the superconducting element (20).

  11. Experimental verification of the axial and lateral stiffness of large W7-X rectangular bellows

    International Nuclear Information System (INIS)

    Reich, J.; Cardella, A.; Koppe, T.; Missal, B.; Capriccioli, A.; Loehrer, W.; Langone, S.; Sassone, P.C.

    2006-01-01

    The WENDELSTEIN 7-X (W7-X) is a super-conducting helical advanced stellarator. W7-X is provided with 299 ports, which connect the plasma vessel with the outer vessel. All the ports are equipped with bellows, which, during bake-out and final adjustment, compensate the relative movements of the vessels. The bellows have different shapes and dimensions ranging from 100 mm circular to 1170 x 570 mm rectangular sizes. During various load-cases the axial and lateral stiffness of all bellows will create a resulting spring-force which acts on the supports of the vessels directly. The higher the stiffness the more is the significant influence on the supports. The lateral stiffness which was calculated with the established standard EJMA-code (Expansion Joint Manufacturers Association) seemed to be relatively small. This appeared to be not correct in particular for non circular bellows. That is why the stiffness of rectangular, multi-layer bellows have then been re-calculated with the Finite Element Method (FEM) code ANSYS. The maximum difference between the FEM and EJMA code resulted to be up to 250 % in particular with movements along the longer side of the bellows. In order to clarify the differences a test-campaign with the largest rectangular bellows was performed. A special test rack allowed predefined displacements in pure lateral and axial directions taking into consideration of the friction in the moving elements. During the tests the load-displacement diagram was recorded permanently. The outcome of the FEM-results was then verified by the tests in axial and lateral directions. The EJMA-code is well proved for circular bellows. The tests showed that instead any calculation of rectangular bellows has to be confirmed by experiments. The paper summarises the calculation, describes the test activities, the apparatus and reports the final results. (author)

  12. New superconducting coil configuration for energy storage

    International Nuclear Information System (INIS)

    Tokorabet, M.; Mailfert, A.; Colteu, A.

    1998-01-01

    Energy storage using superconducting coils involves the problem of electromagnetic field pollution outside the considered system. Different configurations are widely studied: the torus, the alone solenoid and multiple parallel solenoids enclosed in one container. A new configuration which minimizes the external pollution is studied in this paper. The theoretical system is composed of two spherical distributions of the current which are concentric. The analytical study uses solution of Laplace equations. Parametric study covers energy, flux density and geometrical data. The second study concerns the numerical approach of this design using coaxial solenoids. A comparison between this new system and the known systems is presented as a conclusion. (orig.)

  13. Investigation of the mechanical and electrical properties of superconducting coils

    International Nuclear Information System (INIS)

    Saito, T.; Yamagiwa, T.; Hara, K.; Kojima, Y.; Hosoyama, K.; Mori, A.; Nojima, K.; Okamoto, Y.; Takabayashi, S.; Tanaka, T.

    1994-01-01

    Measurement of elastic (Young's) modulus of the superconducting coil and electrical punch-through test have been performed at LBL to understand the mechanical and electrical properties of the superconducting coils. The authors have investigated the elastic modulus of the superconducting coils with six kinds of insulators (made with polyimide-fiberglass-epoxy and all polyimide insulation with epoxy/polyimide adhesive) at room and liquid nitrogen temperatures using samples made of 10 stacks of superconducting cables. The samples are cured under varying compression to investigate the curing pressure dependence of Young's modulus of the coils with six kinds of the insulation system. The electrical punch-through test has also performed under compression at room and liquid nitrogen temperatures to investigate electrical integrity of the insulated coils. The tensile strength test of four kinds of polyimide films has been performed at various temperatures (between cryogenic and coil curing temperatures) to understand the mechanical properties of the films

  14. Superconducting coil system and methods of assembling the same

    Science.gov (United States)

    Rajput-Ghoshal, Renuka; Rochford, James H.; Ghoshal, Probir K.

    2016-01-19

    A superconducting magnet apparatus is provided. The superconducting magnet apparatus includes a power source configured to generate a current; a first switch coupled in parallel to the power source; a second switch coupled in series to the power source; a coil coupled in parallel to the first switch and the second switch; and a passive quench protection device coupled to the coil and configured to by-pass the current around the coil and to decouple the coil from the power source when the coil experiences a quench.

  15. Use of high current density superconducting coils in fusion devices

    International Nuclear Information System (INIS)

    Green, M.A.

    1979-11-01

    Superconducting magnets will play an important role in fusion research in years to come. The magnets which are currently proposed for fusion research use the concept of cryostability to insure stable operation of the superconducting coils. This paper proposes the use of adiabatically stable high current density superconducting coils in some types of fusion devices. The advantages of this approach are much lower system cold mass, enhanced cryogenic safety, increased access to the plasma and lower cost

  16. Superconducting coil design for a tokamak experimental power reactor

    International Nuclear Information System (INIS)

    Turner, L.R.; Wang, S.T.; Smelser, P.

    1977-01-01

    Superconducting toroidal field (TF) and polodial-field (PF) coils have been designed for the proposed Argonne National Laboratory experimental power reactor (EPR). Features of the design include: (1) Peak field of 8 T at 4.2 K or 10 T at 3.0 K. (2) Constant-tension shape for the TF coils, corrected for the finite number (16) of coils. (3) Analysis of errors in coil alignment. (4) Comparison of safety aspects of series-connected and parallel-connected coils. (5) A 60 kA sheet conductor of NbTi with copper stabilizer and stainless steel for support. (6) Superconducting PF coils outside the TF coils. (7) The TF coils shielded from pulsed fields by high-purity aluminum

  17. Design and assembly technology for the thermal insulation of the W7-X cryostat

    Energy Technology Data Exchange (ETDEWEB)

    Risse, K., E-mail: konrad.risse@ipp.mpg.de [Max-Planck-Institut fuer Plasmaphysik (IPP), Euratom Association, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Nagel, M.; Pietsch, M.; Braatz, A. [Max-Planck-Institut fuer Plasmaphysik (IPP), Euratom Association, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Binni, A. [MAN Diesel and Turbo SE, Dpt. OSA, Werftstrasse 17, D-94469 Deggendorf (Germany); Posselt, H. [Linde AG Engineering Div., Dr.-Carl-von-Linde-Strasse 6-14, D-82049 Hoellriegelskreuth (Germany)

    2011-10-15

    The Max-Planck-Institut fuer Plasmaphysik in Greifswald is building up the stellarator fusion experiment Wendelstein 7-X (W7-X). To operate the superconducting magnet system the vacuum and the cold structures are protected by a thermal insulated cryostat. The plasma vessel forms the inner cryostat wall, the outer wall is realised by a thermal insulated outer vessel. In addition 254 thermal insulated ports are fed through the cryogenic vacuum to allow the access to the plasma vessel for heating systems, supply lines or plasma diagnostics. The thermal insulation is being manufactured and assembled by MAN Diesel and Turbo SE (Germany). It consists of a multi-layer insulation (MLI) made of aluminized Kapton with a silk like fibreglass spacer and a thermal shield covering the inner cryostat surfaces. The shield on the plasma vessel is made of fibreglass reinforced epoxy resin with integrated copper meshes. The outer vessel insulation is made of brass panels with an average size of 3.3 x 2.0 m{sup 2}. Cooling loops made of stainless steel are connected via copper strips to the brass panels. Especially the complex 3 D shape of the plasma vessel, the restricted space inside the cryostat and the consideration of the operational component movements influenced the design work heavily. The manufacturing and the assembly has to fulfil stringent geometrical tolerances e.g. for the outer vessel panels +3/-2 mm.

  18. Design and assembly technology for the thermal insulation of the W7-X cryostat

    International Nuclear Information System (INIS)

    Risse, K.; Nagel, M.; Pietsch, M.; Braatz, A.; Binni, A.; Posselt, H.

    2011-01-01

    The Max-Planck-Institut fuer Plasmaphysik in Greifswald is building up the stellarator fusion experiment Wendelstein 7-X (W7-X). To operate the superconducting magnet system the vacuum and the cold structures are protected by a thermal insulated cryostat. The plasma vessel forms the inner cryostat wall, the outer wall is realised by a thermal insulated outer vessel. In addition 254 thermal insulated ports are fed through the cryogenic vacuum to allow the access to the plasma vessel for heating systems, supply lines or plasma diagnostics. The thermal insulation is being manufactured and assembled by MAN Diesel and Turbo SE (Germany). It consists of a multi-layer insulation (MLI) made of aluminized Kapton with a silk like fibreglass spacer and a thermal shield covering the inner cryostat surfaces. The shield on the plasma vessel is made of fibreglass reinforced epoxy resin with integrated copper meshes. The outer vessel insulation is made of brass panels with an average size of 3.3 x 2.0 m 2 . Cooling loops made of stainless steel are connected via copper strips to the brass panels. Especially the complex 3 D shape of the plasma vessel, the restricted space inside the cryostat and the consideration of the operational component movements influenced the design work heavily. The manufacturing and the assembly has to fulfil stringent geometrical tolerances e.g. for the outer vessel panels +3/-2 mm.

  19. Superconductive magnet having shim coils and quench protection circuits

    International Nuclear Information System (INIS)

    Schwall, R.E.

    1987-01-01

    A superconductive magnet is described comprising: a first persistent current loop comprising a first superconductor and a main coil connected to the first superconductor, the main coil being operative in response to superconduction therein to generate a primary magnetic field; a second persistent current loop comprising a second superconductor and a shim coil connected thereto, the shim coil being operative in response to superconduction therein to generate a corrective field for correcting aberrations in a predetermined gradient in the primary magnetic field, the shim coil having fewer turns than the main coil and being inductively coupled therewith whereby small changes in the current in the main coil cause much greater changes in the current in the shim coil. The magnet is characterized by an improvement which consists of: a first heater connected across the second persistent loop in parallel with the shim coil, the first heater being normally inoperative to carry current while the shim coil and the second superconductor are superconducting, the first heater being operative in response to current therein to heat the shim coil to a resistive state; and protective circuit means comprising a second heater connected to the main coil for carrying current from the main coil upon quenching of the main coil, the second heater being disposed in thermal contact with the second superconductor to heat the second superconductor to a resistive state in response to the current from the main coil to thereby divert current in the second persistent loop through the second heater causing it to heat the shim coil to a resistive state and resistively dissipate energy therein

  20. Winding machines for the manufacturing of superconductive coils of the main European fusion research machines

    International Nuclear Information System (INIS)

    Cazzaniga, Rodolfo; Valle, N.; D'Urzo, C.

    2005-01-01

    The successful construction of large magnets passes through the development and application of non-conventional manufacturing processes. A difficult and delicate step in the manufacturing of superconducting coils is the conductor winding technique. It is often a challenging and technologically advanced process, developed according to the requirements of each project. An important aspect during the winding is to avoid any deformation of the cable cross section leading to a damage of the strands and to maintain the design features of the cable. A second aspect is to assure the suitable repeatability and a production rate for an industrial process. The winding line is a system of different machines linked and tuned together properly designed for each project. An adapted software assures the overall process control. TPA realized for ANSALDO Superconduttori the winding lines for many projects: TFMC (NET-TEAM), CMS (INFN-CERN), WENDELSTEIN W7-X (Max Planck Institute, IPP), etc. The experience acquired in this field by ANSALDO Superconduttori and by TPA (as manufacturing tools and equipments supplier) has been acknowledged by CERN with 'The CMS Gold Award' of the Year 2004. The paper describes the main features of the winding lines, the main problems, the technical solutions used for the above mentioned projects and the new ideas for the forthcoming ones

  1. Globally optimal superconducting magnets part II: symmetric MSE coil arrangement.

    Science.gov (United States)

    Tieng, Quang M; Vegh, Viktor; Brereton, Ian M

    2009-01-01

    A globally optimal superconducting magnet coil design procedure based on the Minimum Stored Energy (MSE) current density map is outlined. The method has the ability to arrange coils in a manner that generates a strong and homogeneous axial magnetic field over a predefined region, and ensures the stray field external to the assembly and peak magnetic field at the wires are in acceptable ranges. The outlined strategy of allocating coils within a given domain suggests that coils should be placed around the perimeter of the domain with adjacent coils possessing alternating winding directions for optimum performance. The underlying current density maps from which the coils themselves are derived are unique, and optimized to possess minimal stored energy. Therefore, the method produces magnet designs with the lowest possible overall stored energy. Optimal coil layouts are provided for unshielded and shielded short bore symmetric superconducting magnets.

  2. Quench simulation of SMES consisting of some superconducting coils

    International Nuclear Information System (INIS)

    Noguchi, S.; Oga, Y.; Igarashi, H.

    2011-01-01

    A chain of quenches may be caused by a quench of one element coil when SMES is consists of many element coils. To avoid the chain of quenches, the energy stored in element coil has to be quickly discharged. The cause of the chain of the quenches is the short time constant of the decreasing current of the quenched coil. In recent years, many HTS superconducting magnetic energy storage (HTS-SMES) systems are investigated and designed. They usually consist of some superconducting element coils due to storing excessively high energy. If one of them was quenched, the storage energy of the superconducting element coil quenched has to be immediately dispersed to protect the HTS-SMES system. As the result, the current of the other element coils, which do not reach to quench, increases since the magnetic coupling between the quenched element coil and the others are excessively strong. The increase of the current may cause the quench of the other element coils. If the energy dispersion of the element coil quenched was failed, the other superconducting element coil would be quenched in series. Therefore, it is necessary to investigate the behavior of the HTS-SMES after quenching one or more element coils. To protect a chain of quenches, it is also important to investigate the time constant of the coils. We have developed a simulation code to investigate the behavior of the HTS-SMES. By the quench simulation, it is indicated that a chain of quenches is caused by a quench of one element coil.

  3. Fault-current limiter using a superconducting coil

    International Nuclear Information System (INIS)

    Boenig, H.J.; Paice, D.A.

    1982-01-01

    A novel circuit, consisting of solid-state diodes and a biased superconducting coil, for limiting the fault currents in three-phase ac systems is presented. A modification of the basic circuit results in a solid-state ac breaker with current-limiting features. The operating characteristics of the fault-current limiter and the ac breaker are analyzed. An optimization procedure for sizing the superconducting coil is derived

  4. SSC [Superconducting Super Collider] dipole coil production tooling

    International Nuclear Information System (INIS)

    Carson, J.A.; Barczak, E.J.; Bossert, R.C.; Brandt, J.S.; Smith, G.A.

    1989-03-01

    Superconducting Super Collider dipole coils must be produced to high precision to ensure uniform prestress and even conductor distribution within the collared coil assembly. Tooling is being prepared at Fermilab for the production of high precision 1M and 16.6M SSC dipole coils suitable for mass production. The design and construction methods builds on the Tevatron tooling and production experience. Details of the design and construction methods and measured coil uniformity of 1M coils will be presented. 4 refs., 10 figs

  5. Tight aspect ratio tokamak power reactor with superconducting TF coils

    International Nuclear Information System (INIS)

    Nishio, S.; Tobita, K.; Konishi, S.; Ando, T.; Hiroki, S.; Kuroda, T.; Yamauchi, M.; Azumi, M.; Nagata, M.

    2003-01-01

    Tight aspect ratio tokamak power reactor with super-conducting toroidal field (TF) coils has been proposed. A center solenoid coil system and an inboard blanket were discarded. The key point was how to find the engineering design solution of the TF coil system with the high field and high current density. The coil system with the center post radius of less than 1 m can generate the maximum field of ∼ 20 T. This coil system causes a compact reactor concept, where the plasma major and minor radii of 3.75 m and 1.9 m, respectively and the fusion power of 1.8 GW. (author)

  6. Playing catch with energy between two superconducting coils

    International Nuclear Information System (INIS)

    Masuda, Masayoshi; Shintomi, Takakazu; Asaji, Kiyoyuki.

    1979-03-01

    The first performance of playing catch with energy between two 100 kJ superconducting magnets has been presented. The mechanism of the energy transfer as an interface between the superconducting coils is a thyristorized DC-AC-DC converter. The obtained experimental efficiency of energy transfer has been compared with the theory and good agreement has been obtained. The method will offer a versatile extension of superconductive technique in energy problems. (author)

  7. Tore-Supra: a Tokamak with superconducting toroidal field coils

    International Nuclear Information System (INIS)

    Turck, B.

    1987-07-01

    Tore Supra is a tokamak under construction on the site of Cen Cadarache by the Euratom-CEA Association. The machine technology integrates all problems related to the fabrication and the operation of large superconducting coils and of the associated cryogenic system. Tore Supra will provide a significant experience to prepare the next generation of machines for plasma physics and controlled fusion. Tore Supra is specially designed to implement a large physics program. The superconducting coils make possible the study of plasma confinement in long pulses (more than 60s), the impurities and the stability, and the efficiency of additional heating sources (neutral particle beams and radio frequency heating). The opportunity is taken to recall the particular features and requirements of the superconducting coils of the large future tokamaks in order to point out the problems that have to be faced by any new material (superconducting or not)

  8. New technique for wiring SSC superconducting sextupole corrector coils

    International Nuclear Information System (INIS)

    Leon, B.

    1985-01-01

    There exists in the electronics industry, a technology for the manufacture of printed circuit (PC) boards which is directly transferable into the creation of highly controlled coils, such as the SSC sextupole superconducting corrector coils. This technology, which uses a process of laying down insulated wire in highly controlled patterns has heretofore been confined exclusively to the manufacture of high density printed circuit (PC) boards, possibly due to an ignorance of its utility in the field of precision winding of coils. This ability to fix wires in a well defined location can be used to produce precision wound coils in a very cost-effective manner. These coils may be superior in quality to conventionally made coils. Before describing what can be created with this technology, it is necessary to take a look at this coil winding process, the MULTIWIRE process, and the industry which has utilized this technology

  9. A new technique for wiring SSC superconducting sextupole corrector coils

    International Nuclear Information System (INIS)

    Leon, B.

    1985-01-01

    There exists in the electronics industry, a technology for the manufacture of printed circuit (PC) boards which is directly transferable into the creation of highly controlled coils, such as the SSC sextupole superconducting corrector coils. This technology, which uses a process of laying down insulated wire in highly controlled patterns, has heretofore been confined excusively to the manufacture of high density printed circuit (PC) boards, possibly due to an ignorance of its utility in the field of precision winding of coils. This ability to fix wires in a well defined location can be used to produce precision wound coils in a very cost-effective manner. These coils may be superior in quality to conventionally made coils. Before describing what can be created with this technology, it is necessary to take a look at this coil winding process, the MULTIWIRE process, and the industry which has utilized this technology

  10. Development of superconducting pulsed poloidal coil in JAERI

    International Nuclear Information System (INIS)

    Shimamoto, S.; Okuno, K.; Ando, T.; Tsuji, H.

    1990-01-01

    In the Japan Atomic Energy Research Institute, (JAERI), development work on pulsed superconductors and coils started in 1979, aiming at the demonstration of the applicability of superconducting technologies to pulsed poloidal coils in a fusion reactor. Initially our effort was concentrated mainly on the development of pool-cooled large-current pulsed conductors. Over the past ten years, superconducting technology has made great progress and the forced-flow cooled coil has assumed great importance in the development work. Now the Demo Poloidal Coil Project is in progress in JAERI, and three large forced-flow cooled coils have so far been fabricated and tested. Many improvements have been achieved in ac-loss performance and mechanical characteristics. (author)

  11. Protection of large-stored-energy superconducting coils

    International Nuclear Information System (INIS)

    Kircher, F.

    1975-11-01

    When the stored energy of superconducting magnets increases, the problem of the protection of the coil when a quench occurs becomes more and more important, especially if the structure of the coil is such that the energy can be dissipated only in a small part of the coil. The aim of this paper is first to describe a program which enables to predict the increase of temperature inside the coil for several kinds of protection and to give results for KEK pulsed dipoles (under construction and planned for TRISTAN). (auth.)

  12. Magnesium Diboride Superconducting Coils for Electric Propulsion Systems for Large Aircraft, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The recent development of magnesium diboride superconducting wires makes possible the potential to have much lighter weight superconducting coils for heavy aircraft...

  13. Structural support system for a superconducting magnet coil

    International Nuclear Information System (INIS)

    Meuser, R.B.

    1977-01-01

    The purpose of the ESCAR (Experimental Superconducting Accelerator Ring) project, now under way at the Lawrence Berkeley Laboratory, is to gather data and experience in the design and operation of a relatively small synchrotron employing superconducting magnets. Such data are essential to ensure that the design of future large accelerators may proceed in a knowledgeable and responsible manner. One of the many engineering problems associated with a superconducting magnet is the design of the coil suspension system. The coil, maintained at the temperature of liquid helium, must be held rigidly by a structure that does not conduct too much heat into the liquid helium system. The suspension system used on the ESCAR magnets is described. Topics covered include the coil support system requirements, ESCAR magnet support system, and operating experience

  14. Conceptual design of pellet charge eXchange (PCX) diagnostics for stellarator W7-X

    International Nuclear Information System (INIS)

    Sergeev, Y.Yu; Kuteev, B.V.; Bakhareva, O.A.; Kostrukov, A.Y.; Skokov, V.G.; Petrov, M.P.; Kislyakov, A.I.; Burhenn, R.; Kick, M.

    2002-01-01

    Pellet Charge eXchange diagnostic using Li pellets has been considered for the W7-X machine. Geometry of the experimental set-up and parameters of both lithium pellet injector (LPI) and neutral particle analyser (NPA) were evaluated. It was shown that this diagnostics can provide very well detectable H 0 signal in the range 50 - 1000 keV generated by RF driven H + minority ions in W7-X. The PCX diagnostics will be able to measure H + energy spectra and density profiles in wide range of W7-X plasma parameters. The proposed NPA can be designed on a basis of the NPA ISEP (Ioffe institute) installed now on JET. A pellet light-gas gun can be used to accelerate Li pellets of 2 - 3 mm in size up to 1 km/s velocities. That provides the required pellet penetration into the plasma core. Due to sticky problems with Li operation, a special technique of loading and keeping the pellets in a charger unit of LPI has to be developed. Development of PCX diagnostics for absolute measurements of the confined minority protons requires improvement of the pellet ablation model used. Knowledge of the cloud dimensions and density distributions of different charge states of ions is of special interest. It is necessary to improve predictions of pellet penetrations in non-Maxwellian plasmas as well. An optical system for measurements of pellet cloud density profiles should be foreseen on W7-X. (orig.)

  15. Resistive ballooning modes in W7-AS and W7-X

    International Nuclear Information System (INIS)

    Kaiser, R.

    1993-01-01

    'Critical' pressure gradients due to resistive ballooning modes and their growth rates were computed for the W7-AS stellarator and for a HELIAS configuration with W7-X parameters, and the two configurations were compared. The results are based on the evaluation of a fourth order magnetic differential equation along closed magnetic field lines. The numerical procedure applying a variational approach uses the 'Garching resistive ballooning code', GARBO, which was originally developed for the stability analysis of axisymmetric plasmas. Concerning purely growing modes, this analysis shows that the favourable stability properties of W7-X, already optimized with respect to ideal ballooning modes, persist in the resistive regime: the destabilizing effect of resistivity is largely compensated by the stabilizing contribution of plasma compression. As a consequence, the ideal β limit continues only moderately shifted in the resistive case and likewise ideal ballooning stable equilibria (up to β 0 ≅ 5%) do not become resistively unstable. The situation is different for W7-AS. Greater resistive effects (in comparison with W7-X) are found in a configuration that is already ideally much more unstable. A basic feature in resistive calculations is the occurrence of overstable modes. These modes no longer show a stability threshold and, for realistic values of pressure and resistivity, linear instability is obtained for W7-AS as well as for W7-X, with growth rates and oscillation frequencies in the kilo-Hertz range. (author). 29 refs, 13 figs

  16. Thermo-mechanical analysis of retro-reflectors for interferometry and polarimetry in W7-X

    NARCIS (Netherlands)

    Köppen, M.; Hirsch, M.; Ernst, J.; Vliegenthart, W.A.; Ye, M.Y.; Bykov, V.; Schauer, F.

    2011-01-01

    The stellarator Wendelstein 7-X (W7-X) is presently under construction at the Max-Planck-Institut für Plasmaphysik in Greifswald, Germany. The plasma density profile will be measured by two-colour interferometry where for each line of sight through the plasma the phase shifts of two far-infrared

  17. A high resolution IR/visible imaging system for the W7-X limiter

    International Nuclear Information System (INIS)

    Wurden, G. A.; Dunn, J. P.; Stephey, L. A.; Biedermann, C.; Jakubowski, M. W.; Gamradt, M.

    2016-01-01

    A high-resolution imaging system, consisting of megapixel mid-IR and visible cameras along the same line of sight, has been prepared for the new W7-X stellarator and was operated during Operational Period 1.1 to view one of the five inboard graphite limiters. The radial line of sight, through a large diameter (184 mm clear aperture) uncoated sapphire window, couples a direct viewing 1344 × 784 pixel FLIR SC8303HD camera. A germanium beam-splitter sends visible light to a 1024 × 1024 pixel Allied Vision Technologies Prosilica GX1050 color camera. Both achieve sub-millimeter resolution on the 161 mm wide, inertially cooled, segmented graphite tiles. The IR and visible cameras are controlled via optical fibers over full Camera Link and dual GigE Ethernet (2 Gbit/s data rates) interfaces, respectively. While they are mounted outside the cryostat at a distance of 3.2 m from the limiter, they are close to a large magnetic trim coil and require soft iron shielding. We have taken IR data at 125 Hz to 1.25 kHz frame rates and seen that surface temperature increases in excess of 350 °C, especially on leading edges or defect hot spots. The IR camera sees heat-load stripe patterns on the limiter and has been used to infer limiter power fluxes (∼1–4.5 MW/m"2), during the ECRH heating phase. IR images have also been used calorimetrically between shots to measure equilibrated bulk tile temperature, and hence tile energy inputs (in the range of 30 kJ/tile with 0.6 MW, 6 s heating pulses). Small UFO’s can be seen and tracked by the FLIR camera in some discharges. The calibrated visible color camera (100 Hz frame rate) has also been equipped with narrow band C-III and H-alpha filters, to compare with other diagnostics, and is used for absolute particle flux determination from the limiter surface. Sometimes, but not always, hot-spots in the IR are also seen to be bright in C-III light.

  18. A high resolution IR/visible imaging system for the W7-X limiter

    Energy Technology Data Exchange (ETDEWEB)

    Wurden, G. A., E-mail: wurden@lanl.gov; Dunn, J. P. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Stephey, L. A. [University of Wisconsin, Madison, Wisconsin 53706 (United States); Biedermann, C.; Jakubowski, M. W.; Gamradt, M. [Max Planck Institut für Plasma Physik, Wendelsteinstrasse 1, 17491 Greifswald (Germany)

    2016-11-15

    A high-resolution imaging system, consisting of megapixel mid-IR and visible cameras along the same line of sight, has been prepared for the new W7-X stellarator and was operated during Operational Period 1.1 to view one of the five inboard graphite limiters. The radial line of sight, through a large diameter (184 mm clear aperture) uncoated sapphire window, couples a direct viewing 1344 × 784 pixel FLIR SC8303HD camera. A germanium beam-splitter sends visible light to a 1024 × 1024 pixel Allied Vision Technologies Prosilica GX1050 color camera. Both achieve sub-millimeter resolution on the 161 mm wide, inertially cooled, segmented graphite tiles. The IR and visible cameras are controlled via optical fibers over full Camera Link and dual GigE Ethernet (2 Gbit/s data rates) interfaces, respectively. While they are mounted outside the cryostat at a distance of 3.2 m from the limiter, they are close to a large magnetic trim coil and require soft iron shielding. We have taken IR data at 125 Hz to 1.25 kHz frame rates and seen that surface temperature increases in excess of 350 °C, especially on leading edges or defect hot spots. The IR camera sees heat-load stripe patterns on the limiter and has been used to infer limiter power fluxes (∼1–4.5 MW/m{sup 2}), during the ECRH heating phase. IR images have also been used calorimetrically between shots to measure equilibrated bulk tile temperature, and hence tile energy inputs (in the range of 30 kJ/tile with 0.6 MW, 6 s heating pulses). Small UFO’s can be seen and tracked by the FLIR camera in some discharges. The calibrated visible color camera (100 Hz frame rate) has also been equipped with narrow band C-III and H-alpha filters, to compare with other diagnostics, and is used for absolute particle flux determination from the limiter surface. Sometimes, but not always, hot-spots in the IR are also seen to be bright in C-III light.

  19. Hall probe for measuring high currents in superconducting coils

    International Nuclear Information System (INIS)

    Ferendeci, A.M.

    1986-01-01

    Constructional details of a compact Hall probe for measuring high currents in superconducting coils are given. The Hall probe is easy to assemble and can be inserted or removed from the system without breaking the superconducting loop. Upper current limit of the probe can be increased by using larger magnetic core material. Shielding becomes necessary if the probe holder is to be placed near large current dependent magnetic fields

  20. Program NICOLET to integrate energy loss in superconducting coils

    International Nuclear Information System (INIS)

    Vogel, H.F.

    1978-08-01

    A voltage pickup coil, inductively coupled to the magnetic field of the superconducting coil under test, is connected so its output may be compared with the terminal voltage of the coil under test. The integrated voltage difference is indicative of the resistive volt-seconds. When multiplied with the main coil current, the volt-seconds yield the loss. In other words, a hysteresis loop is obtained if the integrated voltage difference phi = ∫ΔVdt is plotted as a function of the coil current, i. First, time functions of the two signals phi(t) and i(t) are recorded on a dual-trace digital oscilloscope, and these signals are then recorded on magnetic tape. On a CDC-6600, the recorded information is decoded and plotted, and the hysteresis loops are integrated by the set of FORTRAN programs NICOLET described in this report. 4 figures

  1. Pressure rise analysis in superconducting coils during dumping

    International Nuclear Information System (INIS)

    Tada, E.; Shimamoto, S.

    1984-01-01

    This chapter describes the ALPHE computer code, whose purpose is to calculate transient helium behavior in a poolboiling coil and to determine suitable characteristics of safety devices to minimize the maximum pressure and the liquid helium lost during dumping due to quench, or when discharging without normalcy. The analysis is compared with the measurements obtained in the domestic test of the Japanese LCT coil. Topics considered include basic equations (helium behavior, heat generation), manual dump without quench, and dumping due to quench. It is demonstrated that the transient behavior, calculated by ALPHE assuming quasi-static equilibrium between helium and coil, is in good agreement with the experimental measurements observed in the domestic test of the Japanese LCT coil. The engineering technique required for the design criteria of superconducting coils and safety device during dumping is established. ALPHE can be used to design an emergency safety system for a helium refrigerator during dumping

  2. Stability analysis of high temperature superconducting coil in liquid hydrogen

    International Nuclear Information System (INIS)

    Nakayama, T.; Yagai, T.; Tsuda, M.; Hamajima, T.

    2007-01-01

    Recently, it is expected that hydrogen plays an important role in energy source including electric power in near future. Liquid hydrogen has high potential for cooling down superconducting coil wound with high temperature superconductors (HTS), such as BSCCO, YBCO. In this paper, we study stabilities of the coils wound with BSCCO tapes, which are immersed in the liquid hydrogen, and compare stability results with those cooled by liquid helium. We treat a minimum propagation zone (MPZ) theory to evaluate the coil stability considering boiling heat flux of the liquid hydrogen, and specific heat, heat conduction and resistivity of HTS materials as a function of temperature. It is found that the coil cooled by the liquid hydrogen has higher stability margin than that cooled by the liquid helium. We compare the stability margins of both coils wound with Bi-2223/Ag tape and Bi-2212/Ag tape in liquid hydrogen. As a result, it is found that the stability of Bi-2212 coil is equivalent to that of Bi-2223 coil in low and high magnetic field, while the maximum current of Bi-2212 coil exceeds a little bit that of Bi-2223 coil in both magnetic fields

  3. Superconducting self-correcting harmonic coils for pulsed superconducting dipole or multipole magnets

    International Nuclear Information System (INIS)

    Dael, A.; Kircher, F.; Perot, J.

    1975-01-01

    Due to the zero resistance of a superconducting wire, an induced current in a closed superconducting circuit is continuously exactly opposed to its cause. This phenomenon was applied to the correction of the field harmonics of a pulsed magnet by putting short-circuited superconducting coils of particular symmetry in the useful aperture of the magnet. After a review of the main characteristics of such devices, the construction of two correcting coils (quadrupole and sextupole) is described. Experimental results of magnetic efficiency and time behavior are given; they are quite encouraging, since the field harmonics were reduced by one or two orders of magnitude

  4. Progress of the 10 MW ECRH System for W7-X

    International Nuclear Information System (INIS)

    Michel, G.; Brand, P.; Dammertz, G.

    2003-01-01

    The electron cyclotron resonance heating system for the W7-X stellarator is a joint effort of the Max-Planck-Institut fuer Plasmaphysik in Greifswald, the Institut fuer Plasmaforschung Stuttgart and the Forschungszentrum Karlsruhe under the supervision of the latter. Currently it is being constructed at the Greifswald branch of IPP. It will consist of 10 gyrotrons (each with 1 MW 140 GHz in the CW regime) and a quasi optical multi-beam transmission line. W7-X gyrotron candidates are being developed separately in Western Europe and the USA. The prototype phase of the gyrotrons is almost over and significant results have been achieved. The manufacturing of the transmission line is ongoing. An overview over the system including data acquisition and control issues will be given and the current status of the construction will be presented. (authors)

  5. Transport modeling for W7-X on the basis of W7-AS experimental results

    International Nuclear Information System (INIS)

    Beidler, C.D.; Geiger, J.; Maassberg, H.; Marushchenko, N.B.; Turkin, Yu.

    2008-01-01

    Exploratory simulations of plasma confinement in the Wendelstein 7-X (W7-X) stellarator are presented, concentrating on scenarios which simultaneously achieve high temperature and high β (normalized plasma pressure) at the full magnetic field of B=2.5 T. Efficient 1-D transport and ray-tracing codes are combined to provide an approximately self-consistent description of the heating and current drive (ECCD) to be expected from up to 10 MW of electron cyclotron resonance heating (ECRH) in W7-X. Best performance is exhibited in high density (n=1.8x10 20 m -3 ) simulations heated at the second harmonic of the ordinary mode, although control of the magnetic topology at the plasma edge - needed to insure functioning of the island divertor - becomes problematic due to the imbalance of the bootstrap current and ECCD. (author)

  6. Infrared thermography inspection methods applied to the target elements of W7-X divertor

    Energy Technology Data Exchange (ETDEWEB)

    Missirlian, M. [Association Euratom-CEA, CEA/DSM/DRFC, CEA/Cadarache, F-13108 Saint Paul Lez Durance (France)], E-mail: marc.missirlian@cea.fr; Traxler, H. [PLANSEE SE, Technology Center, A-6600 Reutte (Austria); Boscary, J. [Max-Planck-Institut fuer Plasmaphysik, Euratom Association, Boltzmannstr. 2, D-85748 Garching (Germany); Durocher, A.; Escourbiac, F.; Schlosser, J. [Association Euratom-CEA, CEA/DSM/DRFC, CEA/Cadarache, F-13108 Saint Paul Lez Durance (France); Schedler, B.; Schuler, P. [PLANSEE SE, Technology Center, A-6600 Reutte (Austria)

    2007-10-15

    The non-destructive examination (NDE) method is one of the key issues in developing highly loaded plasma-facing components (PFCs) for a next generation fusion devices such as W7-X and ITER. The most critical step is certainly the fabrication and the examination of the bond between the armour and the heat sink. Two inspection systems based on the infrared thermography methods, namely, the transient thermography (SATIR-CEA) and the pulsed thermography (ARGUS-PLANSEE), are being developed and have been applied to the pre-series of target elements of the W7-X divertor. Results obtained from qualification experiences performed on target elements with artificial calibrated defects allowed to demonstrate the capability of the two techniques and raised the efficiency of inspection to a level which is appropriate for industrial application.

  7. Infrared thermography inspection methods applied to the target elements of W7-X divertor

    International Nuclear Information System (INIS)

    Missirlian, M.; Traxler, H.; Boscary, J.; Durocher, A.; Escourbiac, F.; Schlosser, J.; Schedler, B.; Schuler, P.

    2007-01-01

    The non-destructive examination (NDE) method is one of the key issues in developing highly loaded plasma-facing components (PFCs) for a next generation fusion devices such as W7-X and ITER. The most critical step is certainly the fabrication and the examination of the bond between the armour and the heat sink. Two inspection systems based on the infrared thermography methods, namely, the transient thermography (SATIR-CEA) and the pulsed thermography (ARGUS-PLANSEE), are being developed and have been applied to the pre-series of target elements of the W7-X divertor. Results obtained from qualification experiences performed on target elements with artificial calibrated defects allowed to demonstrate the capability of the two techniques and raised the efficiency of inspection to a level which is appropriate for industrial application

  8. A universal portable appliance for stellarator W7-X power supply controlling

    International Nuclear Information System (INIS)

    Xu Weihua

    2001-01-01

    In the project Wendelstein 7-X (W7-X), the popular field bus Profibus has been determined as a uniform connection between the central control system and all the subordinate systems. A universal embedded control system has been developed for W7-X power supply controlling. Siemens 80C167CR micro-controller is used as the central control unit of the system. With a user-defined printed circuit board (PCB) several control buses, i.e., Profibus, CAN, IEEE 488, RS485 and RS232 have been connected to the micro-controller. The corresponding hardware interfaces for the control buses have been designed. A graphic liquid crystal display (LCD) and a user-defined keyboard are used as user interface. The control software will be developed with a C-like language, i.e., C166 for the controller

  9. ECRH scenarios with selective heating of trapped/passing electrons in the W7-X Stellarator

    Directory of Open Access Journals (Sweden)

    Marushchenko N.B.

    2015-01-01

    Full Text Available Using specific features of the magnetic equilibrium in the W7-X stellarator, the ECRH scenarios with combined X2 and X3 modes are discussed. The RF beams for operation with X2 and X3 modes need to be launched from low- and, via the remote steering launcher, high-field-side, respectivaly, in the different crosssections of the device where the maximum and minimum of the magnetic field located. The aim is to explore the possibility of selective heating of the different classes of electrons, passing and trapped, by changing direction of the beam for X3 or switching between the beams for X2 and X3 launched from the different ports. The numerical predictions for this kind of experiments in W7-X are performed by coupled transport and ray tracing codes

  10. The energizing of a NMR superconducting coil by a superconducting rectifier

    International Nuclear Information System (INIS)

    Sikkenga, J.; ten Kate, H.H.J.; van der Klundert, L.J.M.; Knoben, J.; Kraaij, G.J.; Spuorenberg, C.J.G.

    1985-01-01

    NMR magnets require a good homogeneity within a certain volume and an excellent field stability. The homogeneity can be met using a superconducting shim coil system. The field stability requires a constant current, although in many cases the current decay time constant is too low, due to imperfections in the superconducting wire and joints. This can be overcome using a rectifier. The rectifier can also be used to load the coil. The combination and interaction of the superconducting NMR coil (2.0 Tesla and 0.35 m cold bore) and the rectifier (20 W / 1 kA) is tested. The safety of the system is discussed. The shim coil system can compensate the strayfield of the rectifier. The field decay compensation will be discussed

  11. Continuity and enhancement of quality management during commissioning of W7-X

    Energy Technology Data Exchange (ETDEWEB)

    Vilbrandt, Reinhard, E-mail: reinhard.vilbrandt@ipp.mpg.de; Bosch, Hans-Stephan; Feist, Jost-Henrich; Klinger, Thomas

    2015-10-15

    Highlights: • Commissioning follows the W7-X structure into appropriate components, subsystems and systems. • Local and integrated commissioning steps are carried out alternately. • An exact and detailed preparation of all commissioning is absolutely necessary. • Templates support instruction manuals, safety analyses, and commissioning instructions. • Because of safety special attention must be paid to the first putting into service. - Abstract: The commissioning of Wendelstein 7-X, the first numerically optimized stellarator, is a new phase in the project. The general planning and execution of the commissioning of the entire W7-X system follow its structure into appropriate components, subsystems and systems. The approach for taking these systems into operation will lead to so-called local commissioning which is usually executed for individual systems in connection with the necessary peripheral devices and auxiliary systems. The subsequent step-wise testing and commissioning of the systems in connection with the central device of W7-X, including the central safety control, and the central data acquisition system is performed in the second step, the so-called integrated commissioning. This leads directly to the preparation of first plasma operation. New organizational and quality management elements have been added to the running system, or existing, proven tools have been modified. The major new organizational structures and tasks and the quality planning and assurance tools are described in more detail. The experience during the first commissioning steps of the vacuum and cryogenic systems is outlined.

  12. Qualification of high heat flux components: application to target elements of W7-X divertor

    International Nuclear Information System (INIS)

    Missirlian, M; Durocher, A; Grosman, A; Schlosser, J; Boscary, J; Escourbiac, F; Cismondi, F

    2007-01-01

    The development of actively cooled plasma-facing components (PFC) represents one of fusion's most challenging engineering efforts. In this frame, a high-quality bonding between the refractory armour and the heat sink is essential to ensure the heat removal capability and the thermal performances of PFC. Experience gained during manufacturing of Tore Supra actively cooled PFC led to the establishment of a qualification methodology and provided a large experience of acceptance criteria using an active infrared thermography (systeme d'acquisition de traitement infra-rouge, SATIR). This paper presents the application of this qualification process to the W7-X pre-series components, with the objective of assessing and defining workable acceptance criteria that enable reliable predictions of performance at the nominal heat flux requirements in W7-X. Finally, to check the reliability of the non-destructive examination (NDE) method by transient infrared thermography, the newly defined acceptance criteria were applied to W7-X pre-series target elements (batch no. 3). The SATIR results, benchmarked with HHF tests performed on the GLADIS ion beam facility were discussed to assess the ability to detect critical defects at the interface between tiles and heat sink

  13. Epoxy resin casting of trim coils for superconducting cyclotron

    International Nuclear Information System (INIS)

    Hajra, D.P.; Sarkar, S.C.; Saha, Subimal; Chaudhuri, J.; Bhandari, R.K.

    2006-01-01

    The life of any magnet depends on the soundness of the coil insulation, its aging properties and initial and final endurance limitations. The insulation of water-cooled trim coils for superconducting cyclotron is made of glass fibre tape with heat cured unfilled epoxy resin combination. This type of insulation has been selected to achieve excellent stability against thermal and electromagnetic stresses, tight dimensional control, good dielectric strength, non-hygroscopic and considerably low vapour-pressure as it will be inside rough vacuum. The process development and the difficulties encountered for appropriate selection of epoxy resin combination, potting, vacuum process, curing cycle, control of coil dimension to achieve a sound coil absolutely free from cracks, trapped air and voids has been discussed. (author)

  14. Studies on Nb3Sn field coils for superconducting machine

    International Nuclear Information System (INIS)

    Fujino, H.; Nose, S.

    1981-01-01

    This paper describes experimental studies on several coils wound with multifilamentary (MF) Nb 3 Sn cables with reinforcing strip for superconducting rotating machine application. To use a Nb 3 Sn superconductor to field winding of a rotating machine, several coil performances of pre-reacted, bronze processed and stranded MF Nb 3 Sn cables were investigated, mainly in relation to stress effect. Bending strain up to 0.64% in strand and winding stress of 5 kg/mm 2 have resulted in nondegradation in coil performance. A pair of impregnated race-track coils designed for a 30 MVA synchronous condenser was energized successfully up to 80% of critical current without quench. 8 refs

  15. Mechanical properties of ISABELLE superconducting coils

    International Nuclear Information System (INIS)

    Thompson, P.; Bertsche, A.; Fuhrmann, J.; Greene, A.; Grove, E.; Repeta, L.; Short, F.; Tannenbaum, M.; Wanderer, P.

    1981-01-01

    As a part of the manufacturing processes, several mechanical measurements are made on ISABELLE dipoles. These are done both to control the process and to provide information for the evaluation of the behavior of the completed magnets. This paper discusses the Young's Modulus (E = 1-3 x 10 6 psi), the thermal contraction of the coil assembly (ΔL/L = 290 +- 17 x 10 -5 at 77 0 K), and the loss of applied prestress with time

  16. Cryogenic structures of superconducting coils for fusion experimental reactor 'ITER'

    International Nuclear Information System (INIS)

    Nakajima, Hideo; Iguchi, Masahide; Hamada, Kazuya; Okuno, Kiyoshi; Takahashi, Yoshikazu; Shimamoto, Susumu

    2013-01-01

    This paper describes both structural materials and structural design of the Toroidal Field (TF) coil and Central Solenoid (CS) for the International Thermonuclear Experimental Reactor (ITER). All the structural materials used in the superconducting coil system of the ITER are austenitic stainless steels. Although 316LN is used in the most parts of the superconducting coil system, the cryogenic stainless steels, JJ1 and JK2LB, which were newly developed by the Japan Atomic Energy Agency (JAEA) and Japanese steel companies, are used in the highest stress area of the TF coil case and the whole CS conductor jackets, respectively. These two materials became commercially available based on demonstration of productivity and weldability of materials, and evaluations of 4 K mechanical properties of trial products including welded parts. Structural materials are classified into five grades depending on stress distribution in the TF coil case. JAEA made an industrial specification for mass production based on the ITER requirements. In order to simplify quality control in mass production, JAEA has used materials specified in the material section of 'Codes for Fusion Facilities - Rules on Superconducting Magnet Structure (2008)' issued by the Japan Society of Mechanical Engineers (JSME) in October 2008, which was established using an extrapolation method of 4 K material strengths from room temperature strength and chemical compositions developed by JAEA. It enables steel suppliers to easily control the quality of products at room temperature. JAEA has already started actual production with several manufacturing companies. The first JJ1 product to be used in the TF coil case and the first JK2LB jackets for CS were completed in October and September 2013, respectively. (author)

  17. Current contact device for a superconducting magnet coil

    International Nuclear Information System (INIS)

    Hieronymus, H.

    1987-01-01

    The invention concerns a current supply device for a superconducting magnet coil to be shortcircuited, with a separating device per coil end, which contains a fixed cooled contact and a moving contact connected to a power supply device and a mechanical actuating device for closing and opening the contacts. When closing the heated contact on to the cooled contact, relatively large quantities of heat can be transferred to the cooled contact and therefore to the connected superconducting coil end and can cause normal conduction there. The invention therefore provides that the mass ratio of the cooled contact to the moving contact is at least 5:1, preferably at least 10:1, and that the cooled contact part is provided, at the end away from the contact area, with means for increasing the area, for example cooling fins and is connected to the coil end has a thermal resistance between the contact area and the coil end of at least 0.2 k/W, preferably at least 0.5 k/W per 1000 A of current to be transmitted. (orig.) [de

  18. Analysis of mechanical characteristics of superconducting field coil for 17 MW class high temperature superconducting synchronous motor

    International Nuclear Information System (INIS)

    Kim, J. H.; Park, S. I.; Im, S. H.; Kim, H. M.

    2013-01-01

    Superconducting field coils using a high-temperature superconducting (HTS) wires with high current density generate high magnetic field of 2 to 5 [T] and electromagnetic force (Lorentz force) acting on the superconducting field coils also become a very strong from the point of view of a mechanical characteristics. Because mechanical stress caused by these powerful electromagnetic force is one of the factors which worsens the critical current performance and structural characteristics of HTS wire, the mechanical stress analysis should be performed when designing the superconducting field coils. In this paper, as part of structural design of superconducting field coils for 17 MW class superconducting ship propulsion motor, mechanical stress acting on the superconducting field coils was analyzed and structural safety was also determined by the coupling analysis system that is consists of commercial electromagnetic field analysis program and structural analysis program.

  19. SERPENTINE COIL TOPOLOGY FOR BNL DIRECT WIND SUPERCONDUCTING MAGNETS

    International Nuclear Information System (INIS)

    PARKER, B.; ESCALLIER, J.

    2005-01-01

    Serpentine winding, a recent innovation developed at BNL for direct winding superconducting magnets, allows winding a coil layer of arbitrary multipolarity in one continuous winding process and greatly simplifies magnet design and production compared to the planar patterns used before. Serpentine windings were used for the BEPC-II Upgrade and JPARC magnets and are proposed to make compact final focus magnets for the EC. Serpentine patterns exhibit a direct connection between 2D body harmonics and harmonics derived from the integral fields. Straightforward 2D optimization yields good integral field quality with uniformly spaced (natural) coil ends. This and other surprising features of Serpentine windings are addressed in this paper

  20. Characterization of superconducting coil for fault current limitation

    International Nuclear Information System (INIS)

    Polasek, Alexander; Dias, Rodrigo; Niedu, Daniel Brito; Ogasawara, Tsuneharu; Oliveira Filho, Orsino Borges de; Serra, Eduardo Torres; Gomes Junior, George; Amorim, Helio Salim

    2010-01-01

    The increasing power demand has been raising fault currents up to dangerous levels. Superconducting fault current limiters are a promising solution for this problem. In the present work, we studied a superconducting Bi-2212 coil that is used for fault current limitation. Samples were analyzed by XRD, SEM/EDS and measurement of critical temperature (Tc). The Rietveld method was employed for phase quantification. Relatively high Bi-2212 fractions were found. However, Tc varies from a sample to another one. Variations of local Tc are attributed to variations of oxygen content in Bi- 2212 phase. (author)

  1. Mechanical properties of ISABELLE superconducting coils

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, P.; Bertsche, A.; Fuhrmann, J.; Greene, A.; Grove, E.; Repeta, L.; Short, F.; Tannenbaum, M.; Wanderer, P.

    1981-01-01

    As a part of the manufacturing processes, several mechanical measurements are made on ISABELLE dipoles. These are done both to control the process and to provide information for the evaluation of the behavior of the completed magnets. This paper discusses the Young's Modulus (E = 1-3 x 10/sup 6/ psi), the thermal contraction of the coil assembly (..delta..L/L = 290 +- 17 x 10/sup -5/ at 77/sup 0/K), and the loss of applied prestress with time (approx. 20% for times 20 days).

  2. Magnetic field systems employing a superconducting D.C. field coil

    International Nuclear Information System (INIS)

    Bartram, T.C.; Hazell, P.A.

    1977-01-01

    Method and equipment for transferring energy to or from a direct-current superconducting field coil to change the magnetic field generated by the coil in which a second direct-current superconducting coil is used as a storage coil, and energy transfer between the field coil and the storage coil is effected automatically in dependence upon a control program. Preferably, the control program acts upon a variable transformer which is coupled by respective rectifier/inverters to the field and storage coils and also serves for intital supply of energy to the coils

  3. Study of superconducting Nb3Sn coils

    International Nuclear Information System (INIS)

    Vivet, B.

    1963-01-01

    Composite superconducting Nb 3 Sn wires with a diameter of 0.5 mm and a length of about 100 m were made, and Hc-Ic diagrams were plotted up to fields of 80 kgauss for short lengths. Two solenoids producing fields of about 20 kgauss were studied. Nb 3 Sn solenoids, as opposed to those of Nb-Zr or Nb-Ti, appear to have a predictable behavior. Solenoids with less insulation produced stronger fields than heavily insulated solenoids. (author) [fr

  4. Development of an air coil superconducting fault current limiter

    Energy Technology Data Exchange (ETDEWEB)

    Naeckel, Oliver

    2016-07-01

    Electrical power grids are the lifeline of technical infrastructure and fundamental for industry and modern lives. Fault Currents can disrupt the continuous supply of electrical energy, cause instable grid conditions and damage electrical equipment. The Air Coil Superconducting Fault Current Limiter (AC-SFCL) is a measure to effectively limit fault currents. The concept is investigated and proven experimentally by designing, building and successfully testing a 60 kV, 400 V, z=6% demonstrator.

  5. Structural design of superconducting magnets for the large coil program

    International Nuclear Information System (INIS)

    Gray, W.H.; Long, C.J.; Stoddart, W.C.T.

    1979-09-01

    The Large Coil Program (LCP) is a research, development, and demonstration effort specifically for the advancement of the technologies involved in the production of large superconducting magnets. This paper presents a review of the status of the structural designs, analysis methods, and verification tests being performed by the participating LCP design teams in the USA, Switzerland, Japan, and the Federal Republic of Germany. The significant structural mechanics concerns that are being investigated with the LCP are presented

  6. Progress on standardization and automation in software development on W7X

    International Nuclear Information System (INIS)

    Kühner, Georg; Bluhm, Torsten; Heimann, Peter; Hennig, Christine; Kroiss, Hugo; Krom, Jon; Laqua, Heike; Lewerentz, Marc; Maier, Josef; Schacht, Jörg; Spring, Anett; Werner, Andreas; Zilker, Manfred

    2012-01-01

    Highlights: ► For W7X software development the use of ISO/IEC15504-5 is further extended. ► The standard provides a basis to manage software multi-projects for a large system project. ► Adoption of a scrum-like management allows for quick reaction on priority changes. ► A high degree of software build automation allows for quick responses to user requests. ► It provides additional resources to concentrate work on product quality (ISO/IEC 25000). - Abstract: For a complex experiment like W7X being subject to changes all along its projected lifetime the advantages of a formalized software development method have already been stated. Quality standards like ISO/IEC-12207 provide a guideline for structuring of development work and improving process and product quality. A considerable number of tools has emerged supporting and automating parts of development work. On W7X progress has been made during the last years in exploiting the benefit of automation and management during software development: –Continuous build, integration and automated test of software artefacts. ∘Syntax checks and code quality metrics. ∘Documentation generation. ∘Feedback for developers by temporal statistics. –Versioned repository for build products (libraries, executables). –Separate snapshot and release repositories and automatic deployment. –Semi-automatic provisioning of applications. –Feedback from testers and feature requests by ticket system. This toolset is working efficiently and allows the team to concentrate on development. The activity there is presently focused on increasing the quality of the existing software to become a dependable product. Testing of single functions and qualities must be simplified. So a restructuring is underway which relies more on small, individually testable components with standardized interfaces providing the capability to construct arbitrary function aggregates for dedicated tests of quality attributes as availability, reliability

  7. Remote-Steering Antennas for 140 GHz Electron Cyclotron Heating of the Stellarator W7-X

    Directory of Open Access Journals (Sweden)

    Lechte C.

    2017-01-01

    Full Text Available For electron cyclotron resonance heating of the stellarator W7-X at IPP Greifswald, a 140 GHz/10 MW cw millimeter wave system has been built. Two out of 12 launchers will employ a remote-steering design. This paper describes the overall design of the two launchers, and design issues like input coupling structures, manufacturing of corrugated waveguides, optimization of the steering range, integration of vacuum windows, mitrebends and vacuum valves into the launchers, as well as low power tests of the finished waveguides.

  8. Progress on standardization and automation in software development on W7X

    Energy Technology Data Exchange (ETDEWEB)

    Kuehner, Georg, E-mail: kuehner@ipp.mpg.de [Max-Planck-Institut fuer Plasmaphysik, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Bluhm, Torsten [Max-Planck-Institut fuer Plasmaphysik, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Heimann, Peter [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching (Germany); Hennig, Christine [Max-Planck-Institut fuer Plasmaphysik, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Kroiss, Hugo [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching (Germany); Krom, Jon; Laqua, Heike; Lewerentz, Marc [Max-Planck-Institut fuer Plasmaphysik, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Maier, Josef [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching (Germany); Schacht, Joerg; Spring, Anett; Werner, Andreas [Max-Planck-Institut fuer Plasmaphysik, Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Zilker, Manfred [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching (Germany)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer For W7X software development the use of ISO/IEC15504-5 is further extended. Black-Right-Pointing-Pointer The standard provides a basis to manage software multi-projects for a large system project. Black-Right-Pointing-Pointer Adoption of a scrum-like management allows for quick reaction on priority changes. Black-Right-Pointing-Pointer A high degree of software build automation allows for quick responses to user requests. Black-Right-Pointing-Pointer It provides additional resources to concentrate work on product quality (ISO/IEC 25000). - Abstract: For a complex experiment like W7X being subject to changes all along its projected lifetime the advantages of a formalized software development method have already been stated. Quality standards like ISO/IEC-12207 provide a guideline for structuring of development work and improving process and product quality. A considerable number of tools has emerged supporting and automating parts of development work. On W7X progress has been made during the last years in exploiting the benefit of automation and management during software development: -Continuous build, integration and automated test of software artefacts. Ring-Operator Syntax checks and code quality metrics. Ring-Operator Documentation generation. Ring-Operator Feedback for developers by temporal statistics. -Versioned repository for build products (libraries, executables). -Separate snapshot and release repositories and automatic deployment. -Semi-automatic provisioning of applications. -Feedback from testers and feature requests by ticket system. This toolset is working efficiently and allows the team to concentrate on development. The activity there is presently focused on increasing the quality of the existing software to become a dependable product. Testing of single functions and qualities must be simplified. So a restructuring is underway which relies more on small, individually testable components with standardized

  9. Design optimization of superconducting magnetic energy storage coil

    Energy Technology Data Exchange (ETDEWEB)

    Bhunia, Uttam, E-mail: ubhunia@vecc.gov.in; Saha, Subimal; Chakrabarti, Alok

    2014-05-15

    Highlights: • We modeled the optimization formulation that minimizes overall refrigeration load into the SMES cryostat. • Higher the operating current reduces the dynamic load but increases static heat load into the cryostat. • Higher allowable hoop stress reduces both coil volume and refrigeration load. • The formulation can be in general be utilized for any arbitrary specification of SMES coil and conductor type. - Abstract: An optimization formulation has been developed for a superconducting magnetic energy storage (SMES) solenoid-type coil with niobium titanium (Nb–Ti) based Rutherford-type cable that minimizes the cryogenic refrigeration load into the cryostat. Minimization of refrigeration load reduces the operating cost and opens up the possibility to adopt helium re-condensing system using cryo-cooler especially for small-scale SMES system. Dynamic refrigeration load during charging or discharging operational mode of the coil dominates over steady state load. The paper outlines design optimization with practical design constraints like actual critical characteristics of the superconducting cable, maximum allowable hoop stress on winding, etc., with the objective to minimize refrigeration load into the SMES cryostat. Effect of design parameters on refrigeration load is also investigated.

  10. Desgn of a 20-MJ superconducting ohmic-heating coil

    International Nuclear Information System (INIS)

    Singh, S.K.; Murphy, J.H.; Janocko, M.A.; Haller, H.E.; Litz, D.C.; Eckels, P.W.; Rogers, J.D.; Thullen, P.

    1979-01-01

    Conceptual designs of 20-MJ superconducting coils which were developed to demonstrate the feasibility of an ohmic-heating system were discussed. The superconductor materials were NbTi and Nb 3 Sn for the pool boil and forced-flow cooling, respectively. The coils were designed to be cryostable for bipolar operation from +7 to -7 tesla maximum field within one second. The structural design addresses the distribution of structure and structural materials used in the pulsed field environment. The cyclic stresses anticipated and the fatigue limits of the structural materials were examined in view of the operating life of the coil. The coils were designed to generate the flux swings while simultaneously meeting the limitations imposed by cooling, insulation, current density and the stresses in the materials. Both the pool and forced cooled conductors have the same criterion for cryostability, i.e., the conductor must return to the superconducting state from an initial temperature of 20 0 K while the full transport current is flowing through the conductor

  11. An internal superconducting ''holding-coil'' for frozen spin targets

    International Nuclear Information System (INIS)

    Dutz, H.; Gehring, R.; Goertz, S.; Kraemer, D.; Meyer, W.; Reicherz, G.; Thomas, A.

    1995-01-01

    A new concept of a small superconducting holding magnet, placed inside a polarizing refrigerator, has been developed for frozen spin targets. The superconducting wire has been wound on the inner cooling shield of the vertical dilution refrigerator of the Bonn frozen spin target. The maximum field of the magnet is 0.35 T. The total thickness of the superconducting coil consisting of the wire and the copper carrier is of the order of 500 μm. Based on this concept, a frozen spin target is under construction for the measurement of the Gerasimov-Drell-Hearn sum rule with polarized real photons at the Mainz microtron MAMI and the Bonn electron stretcher accelerator ELSA. ((orig.))

  12. An internal superconducting ``holding-coil`` for frozen spin targets

    Energy Technology Data Exchange (ETDEWEB)

    Dutz, H. [Bonn Univ. (Germany). Physikalisches Inst.; Gehring, R. [Bonn Univ. (Germany). Physikalisches Inst.; Goertz, S. [Bonn Univ. (Germany). Physikalisches Inst.; Kraemer, D. [Bonn Univ. (Germany). Physikalisches Inst.; Meyer, W. [Bonn Univ. (Germany). Physikalisches Inst.; Reicherz, G. [Bonn Univ. (Germany). Physikalisches Inst.; Thomas, A. [Bonn Univ. (Germany). Physikalisches Inst.

    1995-03-01

    A new concept of a small superconducting holding magnet, placed inside a polarizing refrigerator, has been developed for frozen spin targets. The superconducting wire has been wound on the inner cooling shield of the vertical dilution refrigerator of the Bonn frozen spin target. The maximum field of the magnet is 0.35 T. The total thickness of the superconducting coil consisting of the wire and the copper carrier is of the order of 500 {mu}m. Based on this concept, a frozen spin target is under construction for the measurement of the Gerasimov-Drell-Hearn sum rule with polarized real photons at the Mainz microtron MAMI and the Bonn electron stretcher accelerator ELSA. ((orig.))

  13. Experimental design: Case studies of diagnostics optimization for W7-X

    International Nuclear Information System (INIS)

    Dreier, H.; Dinklage, A.; Fischer, R.; Hartfuss, H.-J.; Hirsch, M.; Kornejew, P.; Pasch, E.; Turkin, Yu.

    2005-01-01

    The preparation of diagnostics for Wendelstein 7-X is accompanied by diagnostics simulations and optimization. Starting from the physical objectives, the design of diagnostics should incorporate predictive modelling (e.g. transport modelling) and simulations of respective measurements. Although technical constraints are governing design considerations, it appears that several design parameters of different diagnostics can be optimized. However, a general formulation for fusion diagnostics design in terms of optimization is lacking. In this paper, first case studies of Bayesian experimental design aiming at applications on W7-X diagnostics preparation are presented. The information gain of a measurement is formulated as a utility function which is expressed in terms of the Kullback-Leibler divergence. Then, the expected range of data is to be included and the resulting expected utility represents the objective for optimization. Bayesian probability theory gives a framework allowing us for an appropriate formulation of the design problem in terms of probability distribution functions. Results are obtained for the information gain from interferometry and for the design of polychromators for Thomson scattering. For interferometry, studies of the choice of line-of-sights for optimum signal and for the reproduction of gradient positions are presented for circular, elliptical and W7-X geometries. For Thomson scattering, the design of filter transmissions for density and temperature measurements are discussed. (author)

  14. Pre-series and testing route for the serial fabrication of W7-X target elements

    International Nuclear Information System (INIS)

    Boscary, J.; Greuner, H.; Friedrich, T.; Traxler, H.; Mendelevitch, B.; Boeswirth, B.; Schlosser, J.; Smirnow, M.; Stadler, R.

    2009-01-01

    The fabrication of the actively cooled high-heat flux divertor of the WENDELSTEIN 7-X stellarator (W7-X) requires the delivery of 890 target elements, which are designed to withstand a stationary heat flux of 10 MW/m 2 . The organization of the manufacturing and testing route for the serial fabrication is the result of the pre-series activities. Flat CFC Sepcarb NB31 tiles are bonded to CuCrZr copper alloy cooling structure in consecutive steps. A copper layer is active metal cast to CFC tiles, and then an OF-copper layer is added by hot isostatic pressing to produce bi-layer tiles. These tiles are bonded by electron beam welding onto the cooling structure, which was manufactured independently. The introduction of the bi-layer technology proved to be a significant improvement of the bond reliability under thermal cycling loading. This result is also the consequence of the improved bond inspections throughout the manufacturing route performed in the ARGUS pulsed thermography facility of PLANSEE. The repairing process by electron beam welding of the bonding was also qualified. The extended pre-series activities related to the qualification of fabrication processes with the relevant non-destructive examinations aim to minimize the risks for the serial manufacturing and to guarantee the steady-state operation of the W7-X divertor.

  15. Qualifying tests for TRIAM-1M superconducting toroidal magnetic field coil

    Energy Technology Data Exchange (ETDEWEB)

    Nakanura, Yukio; Hiraki, Naoji; Nakamura, Kazuo; Tanaka, Masayoshi; Nagao, Akihiro; Kawasaki, Shoji; Itoh, Satoshi

    1984-09-01

    In the strong toroidal magnetic field experimental facility ''TRIAM-1M'' currently under construction, construction of the superconducting toroidal magnetic field coil and the following qualifying tests conducted on the full-scale superconducting toroidal magnetic field coil actually fabricated are described: (1) coil excitation test, (2) superconducting stability test, (3) external magnetic field application test, and (4) high-speed excitation test. On the basis of these test results, stability was evaluated of the superconducting coil being operated in the tokamak device. In normal tokamak operation, there occurs no normal conduction transition. At the time of plasma disruption, though this transition takes place in part of the coil, the superconducting state is immediately restored. By its electromagnetic force analysis, the superconducting coil is also stable in structure.

  16. Method and apparatus for making superconductive magnet coils

    Science.gov (United States)

    Borden, Albert R.

    1985-01-01

    A curved, shell-type magnet coil, adapted to be used in a superconducting magnet, is wound by providing a mandrel having a tubular cylindrical mid-portion terminating at both ends in tapered end portions formed with longitudinal slots having flexible fingers therebetween. An elongated electrical conductor is wound around an elongated oval-shaped pole island engaged with the outside of the cylindrical mid-portion, to form a multiplicity of oval-shaped turns engaged with a 180-degree segment of the mandrel. The coil turns have longitudinal portions with curved portions therebetween, engaging the tapered end portions of the mandrel. Upon completion of the winding, tapered expansion members are fully inserted into the tapered end portions, to displace the flexible fingers outwardly into a cylindrical form and to displace the curved portions of the turns into a shape conforming to such cylindrical form while also exerting increased tension upon the turns to minimize draping of the turns and to enhance the mechanical integrity of the coil. A half cylinder clamp may then be employed to clamp the coil, whereupon the coil may be solified by the use of an epoxy adhesive.

  17. 30 MJ superconducting coil design and fabrication. Report No. GA-A16104

    International Nuclear Information System (INIS)

    Purcell, J.R.

    1980-09-01

    The Bonneville 30 MJ superconducting stabilizing coil is being constructed by General Atomic under contract to LASL. Upon completion of the design, General Atomic began the procurement of materials and is now ready to start coil winding

  18. Design of a vertical wiggler with superconducting coils

    International Nuclear Information System (INIS)

    Huke, K.; Yamakawa, T.

    1980-01-01

    A vertical wiggler has been designed, which will be installed in the 2.5 GeV electron storage ring under construction at KEK-PF. The wiggler magnet with superconducting coils produces magnetic fields of 6 T and wiggles electron beams in a vertical plane. Synchrotron radiation generated by the wiggler has a critical wavelength of 0.5 Angstroem and has an electric field-vector in the vertical direction, which is very important for precise experiments in various fields of the material sciences. The wiggler consists of three pairs of superconducting coils, an iron magnetic shield, a beam pipe and a liquid helium cryogenic system and is contained in a vacuum vessel which can move up and down together with the wiggler. During the injection time, the vessel is pushed up, so that electron beams with a large spatial spread go through the lower part of the beam pipe, where the aperture of the beam pipe is large enough. After the beam size becomes small due to radiation damping, the vessel is pushed down so that the electron beams go through the narrow gap of the wiggler magnet. Using the iron magnetic shield with iron pole pieces, the ratio between the magnetic field in the gap and the maximum field on the superconductor coils is reduced to 1.1. (orig.)

  19. The application of leak before break concept to W7-X target module

    Energy Technology Data Exchange (ETDEWEB)

    Dundulis, G., E-mail: gintas@mail.lei.lt; Janulionis, R.; Karalevičius, R.

    2013-11-15

    Highlights: • LBB application to Wendelstein 7-X fusion reactor. • R6 method application to crack analysis. • Through wall crack opening analysis. • Determination of leak rate function. • Crack growth analysis. -- Abstract: Fusion is the energy production technology, which could potentially solve problems with growing energy demand of population in the future. Wendelstein 7-X (W7-X) is an experimental stellarator of the helias type fusion reactor currently being built in Greifswald, Germany. This experimental stellarator is a complex structure, such as nuclear power plants and high level of safety requirements should be used for structural integrity analysis. It is thus not possible to obtain simple solutions for general cases, therefore sophisticated methods are necessary for the analysis. Inside the Plasma Vessel (PV) of W7-X there is a number of different components such as pipes, divertors, baffles and targets. A guillotine failure of one component is very dangerous for structural integrity of surrounding components located in PV. For this reason it is very important to evaluate possibility to apply “leak before break” (LBB) concept for W7-X. The LBB concept is widely used in the nuclear industry to describe the idea that in the piping carrying the coolant of a power reactor a leak will occur before a catastrophic break will occurred. LBB allows to conduct the structural design without considering the loads due to postulated line breaks. The LBB analysis was made for the case when plasma vessel is operating in “baking” mode. “Baking” is the mode, when the cooling system is working as a warming system and it heats the plasma vessel structures up to 160 °C in order to release the absorbed gases from the surfaces and to pump them out of the plasma vessel before plasma operation. The LBB analysis was performed for most loaded component of target module. According to the results of the analysis it is possible to conclude that target module 1H

  20. Integrated assessment of thermal hydraulic processes in W7-X fusion experimental facility

    Energy Technology Data Exchange (ETDEWEB)

    Kaliatka, T., E-mail: tadas.kaliatka@lei.lt; Uspuras, E.; Kaliatka, A.

    2017-02-15

    Highlights: • The model of Ingress of Coolant Event experiment facility was developed using the RELAP5 code. • Calculation results were compared with Ingress of Coolant Event experiment data. • Using gained experience, the numerical model of Wendelstein 7-X facility was developed. • Performed analysis approved pressure increase protection system for LOCA event. - Abstract: Energy received from the nuclear fusion reaction is one of the most promising options for generating large amounts of carbon-free energy in the future. However, physical and technical problems existing in this technology are complicated. Several experimental nuclear fusion devices around the world have already been constructed, and several are under construction. However, the processes in the cooling system of the in-vessel components, vacuum vessel and pressure increase protection system of nuclear fusion devices are not widely studied. The largest amount of radioactive materials is concentrated in the vacuum vessel of the fusion device. Vacuum vessel is designed for the vacuum conditions inside the vessel. Rupture of the in-vessel components of the cooling system pipe may lead to a sharp pressure increase and possible damage of the vacuum vessel. To prevent the overpressure, the pressure increase protection system should be designed and implemented. Therefore, systematic and detailed experimental and numerical studies, regarding the thermal-hydraulic processes in cooling system, vacuum vessel and pressure increase protection system, are important and relevant. In this article, the numerical investigation of thermal-hydraulic processes in cooling systems of in-vessel components, vacuum vessels and pressure increase protection system of fusion devices is presented. Using the experience gained from the modelling of “Ingress of Coolant Event” experimental facilities, the numerical model of Wendelstein 7-X (W7-X) experimental fusion device was developed. The integrated analysis of the

  1. Results of the examinations of the W7-X pre-series target elements

    International Nuclear Information System (INIS)

    Boscary, J.; Boeswirth, B.; Greuner, H.; Streibl, B.; Missirlian, M.; Schlosser, J.; Schedler, B.; Scheiber, K.

    2006-01-01

    The highly heat-loaded area of the target plates of the WENDELSTEIN 7-X (W7-X) divertor is formed by 890 water-cooled target elements (TEs). This surface is designed to sustain a maximum stationary heat flux of 10 MW/m 2 and to remove a maximum power of 100 kW per element. Flat tiles made of CFC Sepcarb(r) NB31 are bonded to a CuCrZr heat sink. This joint is manufactured in two stages. In the first step, an OFHC copper interlayer is cast onto the tile by active metal casting (AMC(r)). At this stage, the joint copper-CFC is inspected by X-ray and lock-in thermography. In the second step, the AMC(r)-NB31 tiles are joined to CuCrZr. Two technologies have been investigated: electron beam welding (EBW) and hot isostatic pressing (HIP). The joint copper-CuCrZr is examined by ultrasonic method. At the end of the fabrication, the bond between the heat sink and the CFC tiles is inspected by thermography methods. The produced CFC NB31 material for W7-X showed a large scatter in the tensile strength in the ex-pitch direction in the range of 50 - 110 MPa. Pre-series TEs have been manufactured to qualify the design, the fabrication, the relevant non-destructive examinations (NDEs) and the delivered CFC for the serial production. The whole manufacturing route is validated if the delivered elements withstand operating conditions similar to those in W7-X in the high heat flux (HHF) test facility GLADIS without degradation of performance and integrity. HHF tests did not show any effect that could be attributed to the CFC grade or to the joining method. The HHF test results exhibited a high percentage of defective tiles, indicated by hot spots at the border of the CFC surface. Visual inspections after HHF tests have mostly correlated these spots to the initiation and /or propagation of cracks at the lateral edge of the tiles in CFC at the interface CFC-copper. The pre-series activities have been extended to reduce the stresses at the critical AMC(r) interface. By means of

  2. Testing of improved CFC/Cu bondings for the W7-X divertor targets

    International Nuclear Information System (INIS)

    Greuner, H.; Buswirth, B.; Boscary, J.; Tivey, R.; Plankensteiner, A.; Schedler, B.

    2007-01-01

    Full text of publication follows: Extensive high heat flux (HHF) testing of pre-series divertor targets was performed to establish the industrial process for the manufacturing of 890 targets, which will be needed for the installation of the Wendelstein 7-X (W7-X) divertor. The target design consists of flat tiles of CFC NB31 as plasma facing material bonded by an Active Meta] Casting copper (AMC) interlayer onto a water-cooled CuCrZr structure. This design is required by the specific geometrical requirements of the W7-X divertor. The heat removal capability of this target concept has been demonstrated for the envisaged operational power load of 10 MW/m 2 in previous test series of more than 30 full-scale elements. No large detachment or loss of CFC tiles occurred during cyclic loading tests at 10.5 and 13 MW/m 2 , but growing local de-bonded zones at the free edges of several CFC tiles were observed. Therefore a detailed analysis of the system of CFC/Cu bonding was carried out with respect to a further reduction of the stress at the CFC/Cu interface. Based on the results of the 3/D non-linear thermomechanical FEM analysis of the CFC/Cu interface a set of 17 additional pre-series elements was manufactured by PLANSEE SE. Three types of design variations have been investigated: - adopting an additional plastically compliant Cu interlayer between the cooling structure and the AMC region, - reduced size of CFC tiles, - arrangement of tiles with 90 deg. rotation of the CFC fibre plane. HHF tests were performed in the ion beam test facility GLADIS at IPP Garching with up to 3000 cycles at 10.5 MW/m 2 on this elements. The aim of these tests is to investigate the crack propagation between CFC/Cu and to define the acceptable defect size after 100 HHF cycles as an acceptance criterion for the series manufacturing. The applied criterion should allow the selection of elements for W7-X expected to achieve a suitable operational life time. Finally, the design variant with the

  3. Infrared thermography inspection methods applied to the target elements of W7-X Divertor

    International Nuclear Information System (INIS)

    Missirlian, M.; Durocher, A.; Schlosser, J.; Farjon, J.-L.; Vignal, N.; Traxler, H.; Schedler, B.; Boscary, J.

    2006-01-01

    As heat exhaust capability and lifetime of plasma-facing component (PFC) during in-situ operation are linked to the manufacturing quality, a set of non-destructive testing must be operated during R-and-D and manufacturing phases. Within this framework, advanced non-destructive examination (NDE) methods are one of the key issues to achieve a high level of quality and reliability of joining techniques in the production of high heat flux components but also to develop and built successfully PFCs for a next generation of fusion devices. In this frame, two NDE infrared thermographic approaches, which have been recently applied to the qualification of CFC target elements of the W7-X divertor during the first series production will be discussed in this paper. The first one, developed by CEA (SATIR facility) and used with successfully to the control of the mass-produced actively cooled PFCs on Tore Supra, is based on the transient thermography where the testing protocol consists in inducing a thermal transient within the heat sink structure by an alternative hot/cold water flow. The second one, recently developed by PLANSEE (ARGUS facility), is based on the pulsed thermography where the component is heated externally by a single powerful flash of light. Results obtained on qualification experiences performed during the first series production of W7-X divertor components representing about thirty mock-ups with artificial and manufacturing defects, demonstrated the capabilities of these two methods and raised the efficiency of inspection to a level which is appropriate for industrial application. This comparative study, associated to a cross-checking analysis between the high heat flux performance tests and these inspection methods by infrared thermography, showed a good reproducibility and allowed to set a detectable limit specific at each method. Finally, the detectability of relevant defects showed excellent coincidence with thermal images obtained from high heat flux

  4. Simulation of pulse height analysis soft X-ray spectra expected from W7-X

    Science.gov (United States)

    Jabłoński, S.; Czarnecka, A.; Kubkowska, M.; Ryć, L.; Weller, A.; Biedermann, C.; König, R.; W7-X Team

    2015-10-01

    A computer code named RayX has been developed for checking the performance of a spectroscopy system and optimizing individual parts, like detectors and filters for the pulse height analysis (PHA) diagnostic system designed for the stellarator W7-X. Using the code, the intensity and shape of the X-ray spectra are simulated for different plasma scenarios characterized by varying the temperature and density profiles as well as the electron cyclotron resonance heating (ECRH) power over a wide range. In the simulations of the recorded spectra, the influence of geometrical configuration changes of the diagnostic system (pinhole size, detector size, location of each diagnostic component), of the timing of data collection, as well as of the type and thickness of filters are being investigated. The atomic processes of free-free (bremsstrahlung), free-bound (recombination radiation), and bound-bound emission (line radiation) are considered. For the impurities fractional abundancies of 3% carbon (C), 0.5% oxygen (O) and 0.002% iron (Fe) are taken into account. Information about the number of photons which reach the detector and the current generated inside the detector is given. It is shown that the distance between pinhole and detector has a larger impact on the registered spectra (intensity and total number of photons) than the distance between plasma and pinhole. Based on the results of the simulations, the expected optimal positions of the individual components (pinholes, detectors) were defined for the PHA W7-X diagnostic system. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics

  5. Current control of superconducting coils for fusion experimental facility

    International Nuclear Information System (INIS)

    Ise, T.; Etou, D.; Chikaraishi, H.; Takami, S.; Inoue, T.

    2003-01-01

    The LHD (Large Helical Device) has twelve superconducting coils and six dc power supplies, and following specifications are required for its control system; each coil current must be controlled independently, the steady state control error is less than 0.01% of the reference value, the current settling time for 0.1% of control error is less than 1 second, and the control system must be robust against turbulence caused by appearance and disappearance of the plasma, parameter errors and external electro-magnetic noises. In this paper, the design and test results of the coil current control system for the LHD are described. The good response and robustness are in the relation of trade off each other. H-infinity controller is one of schemes to guarantee robustness for stability. However, the independent responses of six coils were impossible by the H-infinity controller only. To resolve this problem, we applied a feed-forward control with the H-infinity control. Moreover, the advanced design method of H-infinity controller using μ-synthesis was applied to guarantee the control performance in the whole operating condition. As a result, good control results were obtained by experiments. (author)

  6. Simulation of the coil winder for the superconducting supercollider

    International Nuclear Information System (INIS)

    Carnal, C.L.

    1994-01-01

    A unique apparatus has been designed to shape the magnet windings for the Superconducting Supercollider (SSC). The magnet windings of the SSC consist of conductor coils which are placed around a torus to generate a strong magnetic field within the torus. Several process variables must be controlled to demanding tolerances during the coil winding operation. The speed of conductor payout must be coordinated from a small spool through two stages of roll formers to the final coil shape on a large bobbin. The amount of plastic deformation in the conductor must be tightly controlled to pack it into the large bobbin with a certain desired force. The control problem consists of multiple interacting control loops. This paper describes a computer simulation of the coil winding apparatus. The Advanced Continuous Simulation Language (ACSL) was used to encode a mathematical model of the system. The objectives of the simulation study were to understand the dynamic behavior of the system and to explore strategies for control. Although the funding for the SSC was canceled, the results of the research and development project for construction of this unique facility will find application in other large-scale construction and manufacturing problems

  7. Structure design of the Westinghouse superconducting magnet for the Large Coil Program

    International Nuclear Information System (INIS)

    Domeisen, F.N.; Hackworth, D.T.; Stuebinger, L.R.

    1978-01-01

    In the on-going development of superconducting toroidal field coils for tokamak reactors, the Large Coil Program (LCP) managed by Union Carbide Corporation will include the design, fabrication, and testing of large superconducting coils to determine their feasibility for use in the magnetic fusion energy effort. Structural analysis of the large coil is essential to ensure adequate safety in the test coil design and confidence in the scalability of the design. This paper will discuss the action of tensile and shear loads on the various materials used in the coil. These loads are of magnetic and thermal origin

  8. Development of superconducting magnetic bearing using superconducting coil and bulk superconductor

    Energy Technology Data Exchange (ETDEWEB)

    Seino, H; Nagashima, K; Arai, Y [Railway Technical Research Institute, Hikari-cho 2-8-38, Kokubunji-shi, Tokyo (Japan)], E-mail: seino@rtri.or.jp

    2008-02-01

    The authors conducted a study on superconducting magnetic bearing, which consists of superconducting rotor and stator to apply the flywheel energy-storage system for railways. In this study, high temperature bulk superconductor (HTS bulk) was combined with superconducting coils to increase the load capacity of the bearing. In the first step of the study, the thrust rolling bearing was selected for application by using liquid nitrogen cooled HTS bulk. 60mm-diameter HTS bulks and superconducting coil which generated a high gradient of magnetic field by cusp field were adopted as a rotor and a stator for superconducting magnetic bearing, respectively. The results of the static load test and the rotation test, creep of the electromagnetic forces caused by static flux penetration and AC loss due to eccentric rotation were decreased to the level without any problems in substantial use by using two HTS bulks. In the result of verification of static load capacity, levitation force (thrust load) of 8900N or more was supportable, and stable static load capacity was obtainable when weight of 460kg was levitated.

  9. Development of superconducting magnetic bearing using superconducting coil and bulk superconductor

    International Nuclear Information System (INIS)

    Seino, H; Nagashima, K; Arai, Y

    2008-01-01

    The authors conducted a study on superconducting magnetic bearing, which consists of superconducting rotor and stator to apply the flywheel energy-storage system for railways. In this study, high temperature bulk superconductor (HTS bulk) was combined with superconducting coils to increase the load capacity of the bearing. In the first step of the study, the thrust rolling bearing was selected for application by using liquid nitrogen cooled HTS bulk. 60mm-diameter HTS bulks and superconducting coil which generated a high gradient of magnetic field by cusp field were adopted as a rotor and a stator for superconducting magnetic bearing, respectively. The results of the static load test and the rotation test, creep of the electromagnetic forces caused by static flux penetration and AC loss due to eccentric rotation were decreased to the level without any problems in substantial use by using two HTS bulks. In the result of verification of static load capacity, levitation force (thrust load) of 8900N or more was supportable, and stable static load capacity was obtainable when weight of 460kg was levitated

  10. Method of eliminating the training effect in superconducting coils by post-wind preload

    International Nuclear Information System (INIS)

    Heim, J.R.

    1976-01-01

    The training effect in superconducting coils is eliminated by winding the coil with a composite material that includes both a superconductor and a normal material. Stresses are applied to the wound coil in the direction that electromagnetic stresses will be applied to the coil during normal use. The applied stresses are greater than the calculated magnitude of the greatest electromagnetic stresses to be applied to the coil

  11. Levitation properties of superconducting magnetic bearings using superconducting coils and bulk superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Arai, Yuuki; Seino, Hiroshi; Nagashima, Ken [Railway Technical Research Institute, 2-8-38 Hikari-cho, Kokubunji-shi, Tokyo 185-8540 (Japan)

    2010-11-15

    We have been developing a flywheel energy storage system (FESS) with 36 MJ energy capacity for a railway system with superconducting magnetic bearings (SMBs). We prepared two kinds of models using superconducting coils and bulk superconductors (SCs). One model demonstrated SMB load capacity of 20 kN and the other model proved non-contact stable levitation and non-contact rotation with SMBs. Combining these results, the feasibility of a 36 MJ energy capacity FESS with SMBs completely inside a cryostat has been confirmed. In this paper, we report the levitation properties of SMBs in these models.

  12. Levitation properties of superconducting magnetic bearings using superconducting coils and bulk superconductors

    International Nuclear Information System (INIS)

    Arai, Yuuki; Seino, Hiroshi; Nagashima, Ken

    2010-01-01

    We have been developing a flywheel energy storage system (FESS) with 36 MJ energy capacity for a railway system with superconducting magnetic bearings (SMBs). We prepared two kinds of models using superconducting coils and bulk superconductors (SCs). One model demonstrated SMB load capacity of 20 kN and the other model proved non-contact stable levitation and non-contact rotation with SMBs. Combining these results, the feasibility of a 36 MJ energy capacity FESS with SMBs completely inside a cryostat has been confirmed. In this paper, we report the levitation properties of SMBs in these models.

  13. Limit analysis of narrow support elements in W7-X considering the serration effect of the stress-strain relation at 4 K

    International Nuclear Information System (INIS)

    Briani, E.; Gianini, C.; Lucca, F.; Marin, A.; Fellinger, J.; Bykov, V.

    2011-01-01

    The magnet support system of the Wendelstein 7-X (W7-X) fusion stellarator includes challenging components, called Narrow Support Elements (NSEs), placed between the Non Planar Coils (NPCs) at the inboard side and aimed at reducing deformation of the coils. NSEs are small contact elements, with special coating to reduce friction, that have to withstand high compressive and shear forces. The objective of this article is to demonstrate the structural reliability of the NSEs under electromagnetic loading (EML), taking into account in a conservative way the relevant material properties at cryogenic temperatures. To this purpose, an appropriate parametric local Finite Element (FE) model of one highly loaded NSE with its components (pad, pad frame and counter pad) and of a portion of the coils has been developed with ABAQUS code and isotropic elastic-plastic material model with hardening/softening has been used, in order to include the serration effect at 4 K. Different mechanical limit analyses have been performed including consecutive steps of shrink fitting the NSEs in the coils, cooling down to 4 K and gradual increasing of the coil displacements induced by the EML.

  14. Limit analysis of narrow support elements in W7-X considering the serration effect of the stress-strain relation at 4 K

    Energy Technology Data Exchange (ETDEWEB)

    Briani, E., E-mail: erica.briani@ltcalcoli.it [L.T.Calcoli SaS, Piazza Prinetti 26/B, 23807, Merate (Saint Lucia) (Italy); Gianini, C.; Lucca, F.; Marin, A. [L.T.Calcoli SaS, Piazza Prinetti 26/B, 23807, Merate (Saint Lucia) (Italy); Fellinger, J.; Bykov, V. [MPI fur Plasmaphysik (IPP) Wendelsteinstrasse I, D-17491 Greifswald (Germany)

    2011-10-15

    The magnet support system of the Wendelstein 7-X (W7-X) fusion stellarator includes challenging components, called Narrow Support Elements (NSEs), placed between the Non Planar Coils (NPCs) at the inboard side and aimed at reducing deformation of the coils. NSEs are small contact elements, with special coating to reduce friction, that have to withstand high compressive and shear forces. The objective of this article is to demonstrate the structural reliability of the NSEs under electromagnetic loading (EML), taking into account in a conservative way the relevant material properties at cryogenic temperatures. To this purpose, an appropriate parametric local Finite Element (FE) model of one highly loaded NSE with its components (pad, pad frame and counter pad) and of a portion of the coils has been developed with ABAQUS code and isotropic elastic-plastic material model with hardening/softening has been used, in order to include the serration effect at 4 K. Different mechanical limit analyses have been performed including consecutive steps of shrink fitting the NSEs in the coils, cooling down to 4 K and gradual increasing of the coil displacements induced by the EML.

  15. Three-dimensional modelling and numerical optimisation of the W7-X ICRH antenna

    Energy Technology Data Exchange (ETDEWEB)

    Louche, F., E-mail: fabrice.louche@rma.ac.be [Laboratoire de physique des plasmas de l’ERM, Laboratorium voor plasmafysica van de KMS (LPP-ERM/KMS), Ecole Royale Militaire, Koninklijke Militaire School, Brussels (Belgium); Křivská, A.; Messiaen, A.; Ongena, J. [Laboratoire de physique des plasmas de l’ERM, Laboratorium voor plasmafysica van de KMS (LPP-ERM/KMS), Ecole Royale Militaire, Koninklijke Militaire School, Brussels (Belgium); Borsuk, V. [Institute of Energy and Climate Research – Plasma Physics, Forschungszentrum Juelich (Germany); Durodié, F.; Schweer, B. [Laboratoire de physique des plasmas de l’ERM, Laboratorium voor plasmafysica van de KMS (LPP-ERM/KMS), Ecole Royale Militaire, Koninklijke Militaire School, Brussels (Belgium)

    2015-10-15

    Highlights: • A simplified version of the ICRF antenna for the stellarator W7-X has been modelled with the 3D electromagnetic software Microwave Studio. This antenna can be tuned between 25 and 38 MHz with the help of adjustable capacitors. • In previous modellings the front of the antenna was modelled with the help of 3D codes, while the capacitors were modelled as lumped elements with a given DC capacitance. As this approach does not take into account the effect of the internal inductance, a MWS model of these capacitors has been developed. • The initial geometry does not permit the operation at 38 MHz. By modifying some geometrical parameters of the front face, it was possible to increase the frequency band of the antenna, and to increase (up to 25%) the maximum coupled power accounting for the technical constraints on the capacitors. • The W7-X ICRH antenna must be operated at 25 and 38 MHz, and for various toroidal phasings of the strap RF currents. Due to the considered duty cycle it is shown that thanks to a special procedure based on minimisation techniques, it is possible to define a satisfactory optimum geometry in agreement with the specifications of the capacitors. • The various steps of the optimisation are validated with TOPICA simulations. For a given density profile the RF power coupling expectancy can be precisely computed. - Abstract: Ion Cyclotron Resonance Heating (ICRH) is a promising heating and wall conditioning method considered for the W7-X stellarator and a dedicated ICRH antenna has been designed. This antenna must perform several tasks in a long term physics programme: fast particles generation, heating at high densities, current drive and ICRH physics studies. Various minority heating scenarios are considered and two frequency bands will be used. In the present work a design for the low frequency range (25–38 MHz) only is developed. The antenna is made of 2 straps with tap feeds and tuning capacitors with DC capacitance in

  16. Considerations of coil protection and electrical connection schemes in large superconducting toroidal magnet system

    International Nuclear Information System (INIS)

    Yeh, H.T.

    1976-03-01

    A preliminary comparison of several different coil protection and electrical connection schemes for large superconducting toroidal magnet systems (STMS) is carried out. The tentative recommendation is to rely on external dump resistors for coil protection and to connect the coils in the toroidal magnet in several parallel loops (e.g., every fourth coil is connected into a single series loop). For the fault condition when a single coil quenches, the quenched coil should be isolated from its loop by switching devices. The magnet, as a whole, should probably be discharged if more than a few coils have quenched

  17. Simulation of thermal processes in superconducting pancake coils cooled by GM cryocooler

    International Nuclear Information System (INIS)

    Lebioda, M; Rymaszewski, J; Korzeniewska, E

    2014-01-01

    This article presents the thermal model of a small scale superconducting magnetic energy storage system with the closed cycle helium cryocooler. The authors propose the use of contact-cooled coils with maintaining the possibility of the system reconfiguring. The model assumes the use of the second generation superconducting tapes to make the windings in the form of flat discs (pancakes). The paper presents results for a field model of the single pancake coil and the winding system consisting of several coils.

  18. Statistical analysis of the equilibrium configurations of the W7-X stellarator

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, A [Max-Planck-Institut fuer Plasmaphysik, Euratom Association, Greifswald (Germany); Geiger, J [Max-Planck-Institut fuer Plasmaphysik, Euratom Association, Greifswald (Germany); Mc Carthy, P J [Department of Physics, University College Cork, Association EURATOM-DCU, Cork (Ireland)

    2007-05-15

    Equilibrium magnetic configurations of W7-X stellarator plasma were analysed in this study. The statistical method of function parametrization was used to recover the physical properties of the magnetic configurations, such as the flux surface geometry, the magnetic field and the iota profile from simulated experimental data. The study was carried out with a net toroidal current. Idealized 'measurements' were first used to recover the configuration. These ' measurements' were then perturbed with noise and the effect of this perturbation on the recovered configuration parameters was estimated. The noise was scanned over a range large enough to encompass that expected in the actual experiment. In the process, it was possible to ascertain the limit of tolerable noise that can be allowed in the inputs so as not to significantly perturb the outputs recovered with noiseless 'measurements'. Generally, a cubic polynomial model was found to be necessary for noise levels below 10%. For higher noise levels, a quadratic polynomial performed as well as the cubic. The noise level of 10% was also the approximate limit up to which the recovery with ideal measurements was generally reproduced. For the flux geometry recovery, however, the quadratic model performed similarly to the cubic for any value of noise, with the latter model proving to be significantly better only for the noiseless case. Also, with noisy predictors the recovery error for the flux surfaces increases linearly with effective radius from the plasma core up to the edge.

  19. Resource checking and event handling within the W7-X segment control framework

    International Nuclear Information System (INIS)

    Laqua, Heike; Bluhm, Torsten; Heimann, Peter; Hennig, Christine; Kroiss, Hugo; Krom, Jon G.; Kühner, Georg; Lewerentz, Marc; Maier, Josef; Schacht, Jörg; Spring, Anett; Werner, Andreas; Zilker, Manfred

    2012-01-01

    Highlights: ► Support for steady state fusion experiments. ► Off-normal event handling. ► Plasma event driven control. - Abstract: ITER, Wendelstein 7-X, LHD, and TORE SUPRA are experimental facilities designed to lead the way to steady state fusion devices. These experiments require strategies to sustain a discharge in case of unforeseen events, e.g. heat overloads of plasma facing components or the failure of a plasma heating source. A recovery strategy is needed to get the discharge back for physics exploitation. For this purpose the W7-X segment control framework provides means for automated event detection along with options to formulate and initiate a recovery strategy. Besides handling of failures and degradation there are events that represent a desired plasma physical effect. An example for this kind of event is a transition to from Low to High-Confinement mode. These events indicate that a certain plasma state is reached and scientific examination can be altered thus enabling event-driven multiple experiments per discharge. Examples of both kinds of events will be presented and compared to other approaches in the community.

  20. Fabrication and testing of W7-X pre-series target elements

    International Nuclear Information System (INIS)

    Boscary, J; Boeswirth, B; Greuner, H; Grigull, P; Missirlian, M; Plankensteiner, A; Schedler, B; Friedrich, T; Schlosser, J; Streibl, B; Traxler, H

    2007-01-01

    The assembly of the highly-loaded target plates of the WENDELSTEIN 7-X (W7-X) divertor requires the fabrication of 890 target elements (TEs). The plasma facing material is made of CFC NB31 flat tiles bonded to a CuCrZr copper alloy water-cooled heat sink. The elements are designed to remove a stationary heat flux and power up to 10 MW m -2 and 100 kW, respectively. Before launching the serial fabrication, pre-series activities aimed at qualifying the design, the manufacturing route and the non-destructive examinations (NDEs). High heat flux (HHF) tests performed on full-scale pre-series TEs resulted in an improvement of the design of the bond between tiles and heat sink to reduce the stresses during operation. The consequence is the fabrication of additional pre-series TEs to be tested in the HHF facility GLADIS. NDEs of this bond based on thermography methods are developed to define the acceptance criteria suitable for serial fabrication

  1. Results of the examinations of the W7-X pre-series target elements

    International Nuclear Information System (INIS)

    Boscary, J.; Boeswirth, B.; Greuner, H.; Missirlian, M.; Schedler, B.; Scheiber, K.; Schlosser, J.; Streibl, B.

    2007-01-01

    The target elements of the WENDELSTEIN 7-X (W7-X) divertor are designed to sustain a stationary heat flux of 10 MW/m 2 and to remove a maximum power of 100 kW. CFC Sepcarb NB31 tiles are bonded to a water-cooled CuCrZr heat sink in two steps: active metal casting (AMC) of an AMC -copper interlayer to CFC tiles, electron beam welding (EBW) or hot isostatic pressing (HIP) of the AMC -NB31 tiles to CuCrZr. The fabrication of the whole amount of CFC NB31 has been completed. The key target of the pre-series phase is the qualification of this bond based on a series of examinations. The introduction of silicon during the AMC process significantly improved the strength of the joint between CFC and AMC -copper. The strength of the bond is preserved after either EBW or HIP processes. High heat flux testing carried out in the ion beam facility GLADIS exhibited a too high percentage of defective tiles. Pre-series activities have been extended to reduce the stress concentration at the interface between tiles and heat sink by optimizing the design

  2. Experience gained with the 3D machining of the W7-X HHF divertor target elements

    International Nuclear Information System (INIS)

    Junghanns, P.; Boscary, J.; Peacock, A.

    2015-01-01

    Highlights: • The Wendelstein 7-X surface of the actively cooled divertor is built up of 890 individually 3D machined target elements. • To date 300 target elements have been 3D machined with an accuracy of ±0.015 mm. • Copper discovered on the surface of few elements is no risk to operation. - Abstract: The high heat flux (HHF) divertor of W7-X consists of 100 target modules assembled from 890 actively water-cooled target elements protected with CFC tiles. The divertor surface will be built up of individually 3D machined target elements with 89 individual element types. To date 300 of the 890 target elements have been 3D machined with a very good accuracy. To achieve this successful result, a prototyping phase has been conducted to qualify the manufacturing route and to define the acceptance criteria with measures taken to minimize the risk of unacceptable damage during the manufacturing. After the 3D-machining, during the incoming inspection, copper infiltration from the interface between the CFC tiles and the CuCrZr heat sink to the plasma facing surface was detected in a small number of elements.

  3. Scientific component framework for W7-X using service oriented GRID middleware

    International Nuclear Information System (INIS)

    Werner, A.; Svensson, J.; Kuehner, G.; Bluhm, T.; Heimann, P.; Jakob, S.; Hennig, C.; Kroiss, H.; Laqua, H.; Lewerentz, M.; Riemann, H.; Schacht, J.; Spring, A.; Zilker, M.; Maier, J.

    2010-01-01

    Future fusion experiments, aiming to demonstrate steady state reactor operation, require physics driven plasma control based on increasingly complex plasma models. A precondition for establishing such control systems is widely automated data analysis, which can provide integration of multiple diagnostic on a large scale. Even high quality online data evaluation, which is essential for the scientific documentation of the experiment, has to be performed automatically due to the huge data sets being recorded in long discharge runs. An automated system that can handle these requirements will have to be built on reusable software components that can be maintained by the domain experts: diagnosticians, theorists, engineers and others. For Wendelstein 7-X a service oriented architecture seems to be appropriate, in which software components can be exposed as services with well defined interface contracts. Although grid computing has up to now been mainly used for remote job execution, a more promising service oriented middleware has emerged from the recent grid specification, the open grid service architecture (OGSA). It is based on stateful web services defined by the web service resource framework (WSRF) standard. In particular, the statefulness of services allows to setup complex models without unnecessary performance losses by frequent transmission of large and complex data sets. At present, the usability of this technology in the W7-X CoDaC context is under evaluation by first service implementations.

  4. Study on the performance improvement of the high temperature superconducting coil with several separated coils at the edges

    International Nuclear Information System (INIS)

    Ishiguri, S.; Oka, T.; Fukui, S.; Ogawa, J.; Sato, T.

    2008-01-01

    In designing high temperature superconducting (HTS) coils, it is important to secure large magnetic fields and stored energy using shorter tape length. Thus, it is necessary to improve the transport current performance of the coils. The critical current and n-value of an HTS tape depend on magnetic fields and flux angles under constant temperature. Considering these dependencies, we established a model to analyze coil critical current. This model clarifies that relatively large electric fields are generated at the coil edges. This adversely affects the transport current performance. In this study, the coil edge is separated into several coils, keeping the total tape length constant. This increases the coil critical current, stored energy, central magnetic field, and also the coil volume, which contains vacancies created by the separation. To estimate coil performance, we calculated the stored energy density, whose denominator is the increased coil volume. This stored energy density reaches its maximum value when the number of the separated coils is eight. At this optimum separation, the central magnetic field increases by 13%, and the stored energy improves by 43%, compared to a rectangular coil wound with the same tape length

  5. A continuous winding scheme for superconducting tokamak coils with cable-in-conduit conductor

    International Nuclear Information System (INIS)

    Kim, Sang-ho; Chung, Kie-hyung; Lee, Deok Kyo

    2001-01-01

    Superconducting magnet coils are essential for steady-state or long-pulse operation of tokamaks. In an advanced tokamak, the central solenoid (CS) coils are usually divided into several pairs of modules to provide for an extra plasma shaping capability in addition to those available from the shaping (poloidal field) coils. In the conventional pancake winding scheme of superconducting coils, each coil consists of separate superconducting 'double-pancake' coils connected together in series; however, such joints are not superconducting, which is one of the major disadvantages, especially in pulsed operations. A new type of winding was adopted for the ITER CS coil, which consists of cylindrical shell 'layers' joined in series. A disadvantage of this layer winding is its inability to yield modular coils that can provide certain degree of plasma shaping. Joints can be removed in a coil winding pack with the conventional pancake winding scheme, if the conductor is sufficiently long and the winding machine is properly equipped. The compactness, however, cannot be preserved with this scheme. The winding compactness is important since the radial build of the CS coils is one of the major parameters that determine the machine size. In this paper, we present a continuous winding scheme that requires no joints, allows coil fabrication at minimum dimension, and meets the flux swing requirement and other practical aspects

  6. Open midplane designs based on sector coils in superconducting dipoles

    CERN Document Server

    Bruer, J

    2009-01-01

    This paper presents a study of the effects of opening up the midplane in conventional sector coil dipoles, also known as cosè-designs. The open midplane design is a candidate for the higher luminosity upgrade for the LHC, and also for the future beta beam project at CERN, which has the heat deposition mainly concentrated in the midplane of the dipoles. By opening up the midplane, the major part of the spray particles can be avoided, allowing the use of strong superconductive magnets. The aim of this study is to maintain good field quality after a gap in the midplane has been inserted. Short sample field and the electromagnetic force distribution will also be presented for some solutions.

  7. Service oriented architecture for scientific analysis at W7-X. An example of a field line tracer

    Energy Technology Data Exchange (ETDEWEB)

    Bozhenkov, S.A., E-mail: boz@ipp.mpg.de; Geiger, J.; Grahl, M.; Kißlinger, J.; Werner, A.; Wolf, R.C.

    2013-11-15

    Highlights: • We briefly overview available web-service protocols, and explain why SOAP standards are chosen. • We explain the basics of the SOAP technology and give both the usage and development patterns with corresponding examples. • We develop a new W7-X field line tracing service. • The service can calculate Poincaré maps, connection lengths, magnetic coordinates, heat fluxes, etc. with a realistic device geometry. • With the tracer service, we model the influence of 1/1 error field on the W7-X divertor heat loads. -- Abstract: Service oriented architecture based on web-services is a universal method of combining software components. SOAP web-services chosen for W7-X are characterized by strong standards and readily available tools. In this paper the SOAP technology is explained and is illustrated with a new service for field line tracing. The field line tracing package consists of a C++ library and a web-service interface. It features a flexible structure and can handle a realistic machine geometry. The following problems can be solved: getting a field line; making Poincaré maps; calculating flux surface characteristics; calculating heat fluxes to the wall; constructing magnetic coordinates, etc. The service is applied to estimate W7-X divertor loads with an 1/1 error field.

  8. Service oriented architecture for scientific analysis at W7-X. An example of a field line tracer

    International Nuclear Information System (INIS)

    Bozhenkov, S.A.; Geiger, J.; Grahl, M.; Kißlinger, J.; Werner, A.; Wolf, R.C.

    2013-01-01

    Highlights: • We briefly overview available web-service protocols, and explain why SOAP standards are chosen. • We explain the basics of the SOAP technology and give both the usage and development patterns with corresponding examples. • We develop a new W7-X field line tracing service. • The service can calculate Poincaré maps, connection lengths, magnetic coordinates, heat fluxes, etc. with a realistic device geometry. • With the tracer service, we model the influence of 1/1 error field on the W7-X divertor heat loads. -- Abstract: Service oriented architecture based on web-services is a universal method of combining software components. SOAP web-services chosen for W7-X are characterized by strong standards and readily available tools. In this paper the SOAP technology is explained and is illustrated with a new service for field line tracing. The field line tracing package consists of a C++ library and a web-service interface. It features a flexible structure and can handle a realistic machine geometry. The following problems can be solved: getting a field line; making Poincaré maps; calculating flux surface characteristics; calculating heat fluxes to the wall; constructing magnetic coordinates, etc. The service is applied to estimate W7-X divertor loads with an 1/1 error field

  9. Analysis of reflection-coefficient by wireless power transmission using superconducting coils

    International Nuclear Information System (INIS)

    Jeong, In Sung; Choi, Hyo Sang; Chung, Dong Chul

    2017-01-01

    The use of electronic devices such as mobile phones and tablet PCs has increased of late. However, the power which is supplied through wires has a limitation of the free use of devices and portability. Magnetic-resonance wireless power transfer (WPT) can achieve increased transfer distance and efficiency compared to the existing electromagnetic inductive coupling. A superconducting coil can be applied to increase the efficiency and distance of magnetic-resonance WPT. As superconducting coils have lower resistance than copper coils, they can increase the quality factor (Q-factor) and can overcome the limitations of magnetic-resonance WPT. In this study, copper coils were made from ordinary copper under the same condition as the superconducting coils for a comparison experiment. Superconducting coils use liquid nitrogen to keep the critical temperature. As there is a difference of medium between liquid nitrogen and air, liquid nitrogen was also used in the normal conductor coil to compare the experiment with under the same condition. It was confirmed that superconducting coils have a lower reflection-coefficient(S11) than the normal conductor coils

  10. Analysis of reflection-coefficient by wireless power transmission using superconducting coils

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, In Sung; Choi, Hyo Sang [Chosun University, Gwangju (Korea, Republic of); Chung, Dong Chul [Korea Institute of Carbon Convergence Technology, Jeonju (Korea, Republic of)

    2017-06-15

    The use of electronic devices such as mobile phones and tablet PCs has increased of late. However, the power which is supplied through wires has a limitation of the free use of devices and portability. Magnetic-resonance wireless power transfer (WPT) can achieve increased transfer distance and efficiency compared to the existing electromagnetic inductive coupling. A superconducting coil can be applied to increase the efficiency and distance of magnetic-resonance WPT. As superconducting coils have lower resistance than copper coils, they can increase the quality factor (Q-factor) and can overcome the limitations of magnetic-resonance WPT. In this study, copper coils were made from ordinary copper under the same condition as the superconducting coils for a comparison experiment. Superconducting coils use liquid nitrogen to keep the critical temperature. As there is a difference of medium between liquid nitrogen and air, liquid nitrogen was also used in the normal conductor coil to compare the experiment with under the same condition. It was confirmed that superconducting coils have a lower reflection-coefficient(S11) than the normal conductor coils.

  11. Criteria of the efficiency for radiation protection of tokamak reactor superconducting magnet coils

    International Nuclear Information System (INIS)

    Zimin, S.A.

    1988-01-01

    Factors determining serviceability of the main elements (superconductor, stabilizing conductor, insulation) of superconducting magnet coils for tokamak reactors are discussed. It is suggested that the limiting values of total and specific energy release in the material of superconducting coils, increase in electric resistance of the stabilizing conductor, decrease in the superconductor critical current and damage of the superconducting magnet insulation should be used as criteria of the reactor internal radiation protection efficiency. The conclusion is made that neutron fluence in the magnet coil components considered can be used as a generalized criterion of the first approximation for the evaluation of the protection efficiency

  12. Examination of W7-X target elements after high heat flux testing

    International Nuclear Information System (INIS)

    Missirlian, M.; Durocher, A.; Schlosser, J.; Greuner, H.; Schedler, B.

    2007-01-01

    Full text of publication follows: The target elements of Wendelstein 7-X (W7-X) divertor are designed to sustain a stationary heat flux of 10 MW/m 2 and to remove a maximum power load up to 100 kW. The plasma-facing material is made of CFC NB31 flat tiles bonded to a CuCrZr copper alloy water-cooled heat sink. Before launching the serial fabrication, pre-series activities aimed at qualifying the design, the manufacturing route, the relevant non-destructive examination (NDE) methods, and at defining the acceptance criteria for the serial production. High heat flux (HHF) testing is the central activity of this qualification phase and represents a fundamental tool to predict 'critical' defects assembling. Within the framework of this qualification activity, the reception tests performed in the transient infrared thermography test bed SATIR at CEA-Cadarache and HHF testing carried out in the ion beam facility GLADIS at IPP-Garching, exhibited some tiles with thermal inhomogeneities, which initiated and developed during high heat flux testing. Hence, studies were launched in order to better understand this behaviour during cyclic heat loading. This post testing examination was mainly focused on the interface between CFC flat tiles and CuCrZr heat sink to improve if necessary the current design. HHF thermal cycling tests at ∼10 MW/m 2 for 10 s pulse duration each, allowed to assess the performances of target elements and showed some tiles with hot spots close to the edge (stable or progressing). Finally, after the HHF experimental campaign, a comprehensive analysis of some tested elements was carried out by means of infrared thermography inspection SATIR and metallographic examinations. Afterwards correlations between the non destructive SATIR inspection, HHF testing GLADIS and metallographic observation were investigated to assess damage detection, to analyse defect propagation, and to adjust the acceptance criteria valuable for the serial production. This paper will

  13. Analysis of the accident with the coolant discharge into the plasma vessel of the W7-X fusion experimental facility

    Energy Technology Data Exchange (ETDEWEB)

    Ušpuras, E.; Kaliatka, A.; Kaliatka, T., E-mail: tadas@mail.lei.lt

    2013-06-15

    Highlights: • The accident with water ingress into the plasma vessel in Wendelstein nuclear fusion device W7-X was analyzed. • The analysis of the processes in the plasma vessel and ventilation system was performed using thermal-hydraulic RELAP5 Mod3.3 code. • The suitability of pressure increase prevention system was assessed. • All analyses results will be used for the optimization of W7-X design and to ensure safe operation of this nuclear fusion device. -- Abstract: Fusion is the energy production technology, which could potentially solve problems with growing energy demand of population in the future. Starting 2007, Lithuanian Energy Institute (LEI) is a member of European Fusion Development Agreement (EFDA) organization. LEI is cooperating with Max Planck Institute for Plasma Physics (IPP, Germany) in the frames of EFDA project by performing safety analysis of fusion device W7-X. Wendelstein 7-X (W7-X) is an experimental stellarator facility currently being built in Greifswald, Germany, which shall demonstrate that in the future energy could be produced in such type of fusion reactors. In this paper the safety analysis of 40 mm inner diameter coolant pipe rupture in cooling circuit and discharge of steam–water mixture through the leak into plasma vessel during the W7-X no-plasma “baking” operation mode is presented. For the analysis the model of W7-X cooling system (pumps, valves, pipes, hydro-accumulators, and heat exchangers) and plasma vessel was developed by employing system thermal-hydraulic state-of-the-art RELAP5 Mod3.3 code. This paper demonstrated that the developed RELAP5 model enables to analyze the processes in divertor cooling system and plasma vessel. The results of analysis demonstrated that the proposed burst disc, connecting the plasma vessel with venting system, opens and pressure inside plasma vessel does not exceed the limiting 1.1 × 10{sup 5} Pa absolute pressure. Thus, the plasma vessel remains intact after loss

  14. The Calculated and Measured Resistance for Splices between Conductors in a MICE Superconducting Coil

    International Nuclear Information System (INIS)

    Green, Michael A.; Dietderich, Dan; Higley, Hugh; Pan, Heng; Tam, Darren; Trillaud, Federic; Wang, Li; Wu, Hong; Xu, Feng Yu

    2009-01-01

    The resistance of superconducting joints within MICE coils is an important issue particularly for the coupling coils. The MICE tracker solenoids have only two superconducting joints in the three spectrometer set (end coil 1, the center coil and end coil 2). The AFC magnets may have only a single joint within the coil. The coupling coils may have as many as fifteen joints within the coil, due to relatively short piece lengths of the superconductor. LBNL and ICST looked at three types of coil joints. They are: (1) cold fusion butt joints, (2) side-by-side lap joints, and (3) up-down lap joints. A theoretical calculation of the joint resistance was done at LBNL and checked by ICST. After looking at the theoretical resistance of the three types of joints, it was decided that the cold welded butt joint was not an attractive alternative for joints within a MICE superconducting magnet coil. Side-by-side and up-down lap joints were fabricated at ICST using two types of soft solder between the conductors. These conductor joints were tested at LBNL at liquid helium temperatures over a range of magnetic fields. The joint resistance was compared with the theoretical calculations. Measurements of splice strength were also made at 300 K and 77 K.

  15. Effect of reduction of mechanical losses in AC superconducting coils having various FRP bobbins

    International Nuclear Information System (INIS)

    Sekine, N.; Tada, S.; Higuchi, T.; Takao, T.; Yamanaka, A.; Fukui, S.

    2004-01-01

    We have demonstrated in our previous works that a use of the particular structural material for superconducting coils was effective to mechanical-loss reduction under AC operation. In this study, we measured losses to investigate influence of the mechanical losses in the coils having various fiber reinforced plastics (FRPs) with different thermal expansion coefficients. The losses were small in the coils whose winding tension at coil-operating temperature were strong, on the contrary, the losses of the coil having the weak winding tension were large. The coil having the strongest winding tension at liquid helium temperature showed the smallest loss in all coils, and the loss agreed with a value from the Norris's analysis. We think that the mechanical loss becomes almost zero in this coil since the strong tension can prevent the periodic vibration of the superconducting wire. The dependence of the loss on the difference in surface conditions of the materials of the superconducting coil's bobbins was not observed, however, the mechanical losses in AC coils strongly depended on the winding tensions at cryogenic temperature

  16. Development of the SSC [Superconducting Super Collider] trim coil beam tube assembly

    International Nuclear Information System (INIS)

    Skaritka, J.; Kelly, E.; Schneider, W.

    1987-01-01

    The Superconducting Super Collider uses ≅9600 dipole magnets. The magnets have been carefully designed to exhibit minimal magnetic field harmonics. However, because of superconductor magnetization effects, iron saturation and conductor/coil positioning errors, certain harmonic errors are possible and must be corrected by use of multipole correctors called trim coils. For the most efficient use of axial space in the magnet, and lowest possible current, a distributed internal correction coil design is planned. The trim coil assembly is secured to the beam tube, a uhv tube with special strength, size, conductivity and vacuum. The report details the SSC trim coil/beam tube assembly specifications, history, and ongoing development

  17. Development work on superconducting coils for a Large Mirror Fusion Test Facility

    International Nuclear Information System (INIS)

    Cornish, D.N.; Deis, D.W.; Harvey, A.R.; Hirzel, D.G.; Johnston, J.E.; Leber, R.L.; Nelson, R.L.; Zbasnik, J.P.

    1977-01-01

    This article has summarized development work directed toward obtaining the data required to design and build the superconducting coils for MFTF. The methods for fabricating the conductor and joining lengths of the conductor are almost finalized, and the building of the test coil and associated equipment is now well under way

  18. Construction and assembling of the trim coils for the Milan superconducting cyclotron

    International Nuclear Information System (INIS)

    Baccaglioni, G.; Cartegni, G.C.; Fusetti, M.; Gini, L.; Grilli, L.

    1986-01-01

    This paper presents the main characteristics of the trim coils realized for the heavy ions superconducting cyclotron under construction at the Milan University. The guidelines in the choice of the conductor size, of the insulation and cooling parameters are discussed in some details. The main operations in the coils construction, as winding, impregnation, electrical tests and assembling, are described

  19. Preliminary study of ECE imaging concept for W7-X, using the Talbot effect in rectangular waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Iglesias, Daniel; Plaum, Burkhard; Kasparek, Walter; Hirth, Thomas [IGVP, Universitaet Stuttgart (Germany); Hirsch, Matthias [Max-Planck Institut fuer Plasmaphysik, Greifswald (Germany)

    2016-07-01

    For spatially resolved measurements of Electron Cyclotron Emission (ECE) in W7-X, an imaging antenna based on a corrugated rectangular waveguide can be used. The imaging characteristics of the antenna allow a simultaneous operation at multiple angles and frequencies. As a result it is possible to localize a set of points inside the plasma, where the ECE can be measured without the need of mobile components facing the plasma.

  20. Superconducting toroidal field coil current densities for the TFCX

    International Nuclear Information System (INIS)

    Kalsi, S.S.; Hooper, R.J.

    1985-04-01

    A major goal of the Tokamak Fusion Core Experiment (TFCX) study was to minimize the size of the device and achieve lowest cost. Two key factors influencing the size of the device employing superconducting magnets are toroidal field (TF) winding current density and its nuclear heat load withstand capability. Lower winding current density requires larger radial build of the winding pack. Likewise, lower allowable nuclear heating in the winding requires larger shield thickness between the plasma and coil. In order to achieve a low-cost device, it is essential to maximize the winding's current density and nuclear heating withhstand capability. To meet the above objective, the TFCX design specification adopted as goals a nominal winding current density of 3500 A/cm 2 with 10-T peak field at the winding and peak nuclear heat load limits of 1 MW/cm 3 for the nominal design and 50 MW/cm 3 for an advanced design. This study developed justification for these current density and nuclear heat load limits

  1. Design study for superconducting main field coils for the Oak Ridge Isochronous Cyclotron

    International Nuclear Information System (INIS)

    Schwenterly, S.W.; Litherland, P.S.; Ballou, J.K.

    1981-01-01

    The design study described here demonstrated the feasibility of replacing the existing ORIC coils with superconducting magnets. The design is quite conservative, requires no unusual technology, and should result in a coil system with good reliability and durability. The operating regime of ORIC will be considerably extended, and running costs should be reduced. A proposal to continue with detailed design and coil fabrication is currently under review and has been submitted to the Nuclear Science Advisory Committee

  2. Superconducting coil manufacturing method for low current dc beam line magnets

    International Nuclear Information System (INIS)

    Satti, J.A.

    1977-01-01

    A method of manufacturing superconducting multipole coils for 40 to 50 kG dc beam line magnets with low current is described. Small coils were built and tested successfully to short sample characteristics. The coils did not train after the first cooldown. The coils are porous and well cooled to cope with mechanical instability and energy deposited in the coil from the beam particles. The coils are wound with insulated strand cable. The cable is shaped rectangularly for winding simplicity and good tolerances. After the coil is wound, the insulated strands are electrically connected in series. This reduces the operating current and, most important, improves the coil quench propagation due to heat conduction of one strand adjacent to the other. A well distributed quench allows the magnet energy to distribute more uniformly to the copper in the superconductor wire, giving self-protected coils. A one-meter long, 43 kG, 6-inch bore tube superconducting dipole is now being fabricated. The porous coil design and coil winding methods are discussed

  3. Mechanical behavior of the mirror fusion test Facility superconducting magnet coils

    International Nuclear Information System (INIS)

    Horvath, J.A.

    1980-01-01

    The mechanical response to winding and electromagnetic loads of the Mirror Fusion Test Facility (MFTF) superconducting coil pack is presented. The 375-ton (3300 N) MFTF Yin-Yang magnet, presently the world's largest superconducting magnet, is scheduled for acceptance cold-testing in May of 1981. The assembly is made up of two identical coils which together contain over 15 miles (24 km) of superconductor wound in 58 consecutive layers of 24 turns each. Topics associated with mechanical behavior include physical properties of the coil pack and its components, winding pre-load effects, finite element analysis, magnetic load redistribution, and the design impact of predicted conductor motion

  4. Structural design of the superconducting Poloidal Field coils for the Tokamak Physics Experiment

    International Nuclear Information System (INIS)

    O'Connor, T.G.; Zbasnik, J.P.

    1993-01-01

    The Tokamak Physics Experiment concept design uses superconducting coils made from cable-in-conduit conductor to accomplish both magnetic confinement and plasma initiation. The Poloidal Field (PF) magnet system is divided into two subsystems, the central solenoid and the outer ring coils, the latter is focus of this paper. The eddy current heating from the pulsed operation is excessive for a case type construction; therefore, a ''no case'' design has been chosen. This ''no case'' design uses the conductor conduit as the primary structure and the electrical insulation (fiberglass/epoxy wrap) as a structural adhesive. The model integrates electromagnetic analysis and structural analysis into the finite element code ANSYS to solve the problem. PF coil design is assessed by considering a variety of coil current wave forms, corresponding to various operating modes and conditions. The structural analysis shows that the outer ring coils are within the requirements of the fatigue life and fatigue crack growth requirements. The forces produced by the Toroidal Field coils on the PF coils have little effect on the maximum stresses in the PF coils. In addition in an effort to reduce the cost of the coils new elongated PF coils design was proposed which changes the aspect ratio of the outer ring coils to reduce the number of turns in the coils. The compressive stress in the outer ring coils is increased while the tensile stress is decreased

  5. Use of a High-Temperature Superconducting Coil for Magnetic Energy Storage

    International Nuclear Information System (INIS)

    Fagnard, J-F; Crate, D; Jamoye, J-F; Laurent, Ph; Mattivi, B; Cloots, R; Ausloos, M; Genon, A; Vanderbemden, Ph

    2006-01-01

    A high temperature superconducting magnetic energy storage device (SMES) has been realised using a 350 m-long BSCCO tape wound as a ''pancake'' coil. The coil is mounted on a cryocooler allowing temperatures down to 17.2 K to be achieved. The temperature dependence of coil electrical resistance R(T) shows a superconducting transition at T = 102.5 K. Measurements of the V(I) characteristics were performed at several temperatures between 17.2 K and 101.5 K to obtain the temperature dependence of the critical current (using a 1 μV/cm criterion). Critical currents were found to exceed 100 A for T < 30 K. An electronic DC-DC converter was built in order to control the energy flow in and out of the superconducting coil. The converter consists of a MOS transistor bridge switching at a 80 kHz frequency and controlled with standard Pulse Width Modulation (PWM) techniques. The system was tested using a 30 V squared wave power supply as bridge input voltage. The coil current, the bridge input and output voltages were recorded simultaneously. Using a 10 A setpoint current in the superconducting coil, the whole system (coil + DC-DC converter) can provide a stable output voltage showing uninterruptible power supply (UPS) capabilities over 1 s

  6. Core/coil assembly for use in superconducting magnets and method for assembling the same

    Science.gov (United States)

    Kassner, David A.

    1979-01-01

    A core/coil assembly for use in a superconducting magnet of the focusing or bending type used in syncronous particle accelerators comprising a coil assembly contained within an axial bore of the stacked, washer type, carbon steel laminations which comprise the magnet core assembly, and forming an interference fit with said laminations at the operating temperature of said magnet. Also a method for making such core/coil assemblies comprising the steps of cooling the coil assembly to cryogenic temperatures and drawing it rapidly upwards into the bore of said stacked laminations.

  7. Enhancing the design of a superconducting coil for magnetic energy storage systems

    International Nuclear Information System (INIS)

    Indira, Gomathinayagam; UmaMaheswaraRao, Theru; Chandramohan, Sankaralingam

    2015-01-01

    Highlights: • High magnetic flux density of SMES coil to reduce the size. • YBCO Tapes for the construction of HTS magnets. • Relation between energy storage and length of the coil wound by various materials. • Design with a certain length of second-generation HTS. - Abstract: Study and analysis of a coil for Superconducting Magnetic Energy Storage (SMES) system is presented in this paper. Generally, high magnetic flux density is adapted in the design of superconducting coil of SMES to reduce the size of the coil and to increase its energy density. With high magnetic flux density, critical current density of the coil is degraded and so the coil is wound with High Temperature Superconductors (HTS) made of different materials. A comparative study is made to emphasize the relationship between the energy storage and length of the coil wound by Bi2223, SF12100, SCS12100 and YBCO tapes. Recently for the construction of HTS magnets, YBCO tapes have been used. Simulation models for various designs have been developed to analyze the magnetic field distribution for the optimum design of energy storage. The design which gives the maximum stored energy in the coil has been used with a certain length of second-generation HTS. The performance analysis and the results of comparative study are done

  8. Enhancing the design of a superconducting coil for magnetic energy storage systems

    Energy Technology Data Exchange (ETDEWEB)

    Indira, Gomathinayagam, E-mail: gindu80@gmail.com [EEE Department, Prince Shri Venkateshwara Padmavathy Engineering College, Chennai (India); UmaMaheswaraRao, Theru, E-mail: umesh.theru@gmail.com [Divison of Power Engineering and Management, Anna University, Chennai (India); Chandramohan, Sankaralingam, E-mail: cdramo@gmail.com [Divison of Power Engineering and Management, Anna University, Chennai (India)

    2015-01-15

    Highlights: • High magnetic flux density of SMES coil to reduce the size. • YBCO Tapes for the construction of HTS magnets. • Relation between energy storage and length of the coil wound by various materials. • Design with a certain length of second-generation HTS. - Abstract: Study and analysis of a coil for Superconducting Magnetic Energy Storage (SMES) system is presented in this paper. Generally, high magnetic flux density is adapted in the design of superconducting coil of SMES to reduce the size of the coil and to increase its energy density. With high magnetic flux density, critical current density of the coil is degraded and so the coil is wound with High Temperature Superconductors (HTS) made of different materials. A comparative study is made to emphasize the relationship between the energy storage and length of the coil wound by Bi2223, SF12100, SCS12100 and YBCO tapes. Recently for the construction of HTS magnets, YBCO tapes have been used. Simulation models for various designs have been developed to analyze the magnetic field distribution for the optimum design of energy storage. The design which gives the maximum stored energy in the coil has been used with a certain length of second-generation HTS. The performance analysis and the results of comparative study are done.

  9. Test equipment for a flywheel energy storage system using a magnetic bearing composed of superconducting coils and superconducting bulks

    International Nuclear Information System (INIS)

    Ogata, M; Matsue, H; Yamashita, T; Hasegawa, H; Nagashima, K; Maeda, T; Matsuoka, T; Mukoyama, S; Shimizu, H; Horiuchi, S

    2016-01-01

    Energy storage systems are necessary for renewable energy sources such as solar power in order to stabilize their output power, which fluctuates widely depending on the weather. Since ‘flywheel energy storage systems’ (FWSSs) do not use chemical reactions, they do not deteriorate due to charge or discharge. This is an advantage of FWSSs in applications for renewable energy plants. A conventional FWSS has capacity limitation because of the mechanical bearings used to support the flywheel. Therefore, we have designed a superconducting magnetic bearing composed of a superconducting coil stator and a superconducting bulk rotor in order to solve this problem, and have experimentally manufactured a large scale FWSS with a capacity of 100 kWh and an output power of 300 kW. The superconducting magnetic bearing can levitate 4 tons and enables the flywheel to rotate smoothly. A performance confirmation test will be started soon. An overview of the superconducting FWSS is presented in this paper. (paper)

  10. A 1.5 MJ cryostatic stable superconducting ohmic-heating coil

    International Nuclear Information System (INIS)

    Wang, S.-T.; Kim, S.H.; Praeg, W.F.; Krieger, C.I.

    1978-01-01

    As early as FY 1975, ANL had recognized the clear advantage of a superconducting ohmic-heating (OH) coil and proposed a five-year pulsed coil and power supply development program to ERDA. With modest funding made available by ERDA in FY 1977 and the use of substantial equipment inventory at ANL, a small but agressive development program was advanced to the construction of a 1.5 MJ model coil. The principle objective in building the 1.5 MJ ac coil is to demonstrate ac cryostability of a large coil with a dB/dt ranging from 2 T/s up to 14 T/s. The results of basic cable development and tests will be described. The design and construction of a prototype 1.5 MJ cryostable pulsed coil and its nonmetallic cryostat will be presented. (author)

  11. Measurement of core plasma temperature and rotation on W7-X made available by the x-ray imaging crystal spectrometer (XICS)

    Energy Technology Data Exchange (ETDEWEB)

    Pablant, N A; Bitter, M; Burhenn, R; Delgado-Aparicio, L; Ellis, R; Gates, D; Goto, M; Hill, K W; Langenberg, A; Lazerson, S; Mardenfeld, M; Morita, S; Neilson, G H; Oishi, T; Pedersen, T S

    2014-07-01

    A new x-ray imaging crystal spectrometer diagnostic (XICS) is currently being built for installation on W7-X. This diagnostic will contribute to the study of ion and electron thermal transport and the evolution of the radial electric field by providing high resolution temperature and rotation measurements under many plasma conditions, including ECH heated plasmas. Installation is expected before the first experimental campaign (OP1.1), making an important set of measurements available for the first W7-X plasmas. This diagnostic will also work in concert with the HR-XCS diagnostic to provide an excellent diagnostic set for core impurity transport on W7-X.

  12. An experimental mechanical switch for 3 kA driven by superconducting coils

    International Nuclear Information System (INIS)

    Herman, H.J.; Ten Haken, B.; Van de Klundert, L.J.M.

    1986-01-01

    Usually mechanical switches that are built for use in superconducting circuits are driven in some way by a rod which is controlled at room temperature. In this paper, an alternative method to drive the electrodes of the switch is reported. In fact the new device is a superconducting relay that uses an antiseries connection of two superconducting air-core coils. The repulsing force of these relay coils enables the switch to be closed by applying a pressure to the electrodes. The off-state is effected by a set of springs which interrupt the electrodes when the coil current is switched off. We realized that this electro-magnetic method of producing large forces could be promising for driving a mechanical switch. The desired method was demonstrated by an experimental model. A switch-on resistance of 8*10 -8 Ω with a switch current of 3 kA and a contact force of 20 kN was measured

  13. Design Aspects on Winding of an MgB2 Superconducting Generator Coil

    DEFF Research Database (Denmark)

    Magnusson, N.; Eliassen, J.C.; Abrahamsen, Asger Bech

    2015-01-01

    copper conductors at room temperature at one tenth of the wire cost per unit carried current. In the framework of the European project INNWIND.EU, an MgB2 superconducting generator pole will be designed, built and tested. Some of the design aspects of this work with emphasis on the winding process...... and associated coil insulation are discussed. An overall high current density in the coil is of crucial importance to obtain clear benefits compared to conventional solutions. The wire itself may be the most important parameter in that respect. However, the overall current density of the coil is also influenced......% compared to the use of an additional, dedicated, electrical insulation like Kapton for wet-winding or glass-fibre for dry-winding followed by vacuum impregnation. We show the results of a trial winding of 500 m of MgB2 superconducting wire into a double pancake coil using the wet-winding technique...

  14. Static stress analysis of coupling superconducting solenoid coil assembly for muon ionization cooling experiment

    International Nuclear Information System (INIS)

    Pan Heng; Wang Li; Wu Hong; Guo Xinglong; Xu Fengyu

    2010-01-01

    The stresses in the coupling superconducting solenoid coil assembly, which is applied in the Muon Ionization Cooling Experiment (MICE), are critical for the structure design and mechanical stability because of a large diameter and relative high magnetic field. This paper presents an analytical stress solution for the MICE coupling coil assembly. The stress due to winding tension is calculated by assuming the coil package as a set of combined cylinders. The thermal and electromechanical stresses are obtained by solving the partial differential equations of displacement based on the power series expansion method. The analytical stress solution is proved to be feasible by calculating stresses in a tested superconducting solenoid with 2.58 m bore at room temperature. The analytical result of the MICE coupling coil is in good agreement with that of the finite element which shows that the transverse shear stress induced by Lorentz force is principally dominant to magnet instability. (authors)

  15. High-T /SUB c/ Superconducting integrated circuit: a dc SQUID with input coil

    International Nuclear Information System (INIS)

    Di Iorio, M.S.; Beasley, M.R.

    1985-01-01

    We have fabricated a high transition temperature superconducting integrated circuit consisting of a dc SQUID and an input coupling coil. The purpose is to ascertain the generic problems associated with constructing a high-T /SUB c/ circuit as well as to fabricate a high performance dc SQUID. The superconductor used for both the SQUID and the input coil is Nb 3 Sn which must be deposited at 800 0 C. Importantly, the insulator separating SQUID and input coil maintains its integrity at this elevated temperature. A hole in the insulator permits contact to the innermost winding of the coil. This contact has been achieved without significant degradation of the superconductivity. Consequently, the device operates over a wide temperature range, from below 4.2 K to near T /SUB c/

  16. Development and testing of 140 GHz absorber coatings for the water baffle of W7-X cryopumps

    International Nuclear Information System (INIS)

    Floristan, Miriam; Mueller, Philipp; Gebhardt, Andreas; Killinger, Andreas; Gadow, Rainer; Cardella, Antonio; Li, Chuanfei; Stadler, Reinhold; Zangl, Guenter; Hirsch, Matthias; Laqua, Heinrich P.; Kasparek, Walter

    2011-01-01

    Due to the relatively high strayfield radiation (140 GHz) from the electron cyclotron radio frequency heating system to which the W7-X cryopumps are expected to be subjected, coating systems acting as an efficient absorber for 140 GHz radiation have been developed for the water-cooled baffle shield in order to reduce the thermal load on the liquid N shield and the liquid He cryopanel. Several types of oxide ceramic coatings were applied on planar copper substrates by Atmospheric Plasma Spraying. The influence of the process parameters on the coating properties and microwave absorbing capability was analysed. It was found that film thickness and microstructure of the sprayed coatings have a significant influence on microwave absorption behaviour. For Al 2 O 3 /TiO 2 coatings, absorption values over 90% were obtained for the 140 GHz probing beam. After optimisation of the coating structure for maximum microwave absorption, the coating procedure was adapted by special robot trajectories to the complex water baffle geometry. The selected spray parameters and kinematics were then used for the complete coating of four mock-ups, which have been tested in the W7-X strayfield test facility Mistral. The mock-ups showed absorption values of 75%.

  17. Development and testing of 140 GHz absorber coatings for the water baffle of W7-X cryopumps

    Energy Technology Data Exchange (ETDEWEB)

    Floristan, Miriam, E-mail: miriam.floristan@gsame.uni-stuttgart.de [Graduate School for advanced Manufacturing Engineering (GSaME), Universitaet Stuttgart (Germany); Institute for Manufacturing Technologies of Ceramic Components and Composites (IMTCCC), Universitaet Stuttgart, Allmandring 7 b, D-70569 Stuttgart (Germany); Mueller, Philipp; Gebhardt, Andreas; Killinger, Andreas; Gadow, Rainer [Institute for Manufacturing Technologies of Ceramic Components and Composites (IMTCCC), Universitaet Stuttgart, Allmandring 7 b, D-70569 Stuttgart (Germany); Cardella, Antonio [European Commission c/o Wendelstein 7X, Boltzmannstasse 2, D-85748 Garching (Germany); Li, Chuanfei; Stadler, Reinhold; Zangl, Guenter; Hirsch, Matthias; Laqua, Heinrich P. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Assoc., Wendelsteinstrasse 1, D-17491 Greifswald (Germany); Kasparek, Walter [Institut fuer Plasmaforschung, Universitaet Stuttgart, Pfaffenwaldring 31, D-70569 Stuttgart (Germany)

    2011-10-15

    Due to the relatively high strayfield radiation (140 GHz) from the electron cyclotron radio frequency heating system to which the W7-X cryopumps are expected to be subjected, coating systems acting as an efficient absorber for 140 GHz radiation have been developed for the water-cooled baffle shield in order to reduce the thermal load on the liquid N shield and the liquid He cryopanel. Several types of oxide ceramic coatings were applied on planar copper substrates by Atmospheric Plasma Spraying. The influence of the process parameters on the coating properties and microwave absorbing capability was analysed. It was found that film thickness and microstructure of the sprayed coatings have a significant influence on microwave absorption behaviour. For Al{sub 2}O{sub 3}/TiO{sub 2} coatings, absorption values over 90% were obtained for the 140 GHz probing beam. After optimisation of the coating structure for maximum microwave absorption, the coating procedure was adapted by special robot trajectories to the complex water baffle geometry. The selected spray parameters and kinematics were then used for the complete coating of four mock-ups, which have been tested in the W7-X strayfield test facility Mistral. The mock-ups showed absorption values of 75%.

  18. Assessment of W7-X plasma vessel pressurisation in case of LOCA taking into account in-vessel components

    Energy Technology Data Exchange (ETDEWEB)

    Urbonavičius, E., E-mail: Egidijus.Urbonavicius@lei.lt; Povilaitis, M., E-mail: Mantas.Povilaitis@lei.lt; Kontautas, A., E-mail: Aurimas.Kontautas@lei.lt

    2015-11-15

    Highlights: • Analysis of the vacuum vessel response to the LOCA in W7-X was performed using lumped-parameter codes COCOSYS and ASTEC. • Benchmarking of the results received with two codes provides more confidence in results and helps in identification of possible important differences in the modelling. • The performed analysis answered the questions set in the installed plasma vessel venting system during overpressure of PV in case of 40 mm diameter LOCA in “baking” mode. • Differences in time until opening the burst disk observed in ASTEC and COCOSYS results are caused by differences in heat transfer modelling. - Abstract: This paper presents the analysis of W7-X vacuum vessel response taking into account in-vessel components. A detailed analysis of the vacuum vessel response to the loss of coolant accident was performed using lumped-parameter codes COCOSYS and ASTEC. The performed analysis showed that the installed plasma vessel venting system prevents overpressure of PV in case of 40 mm diameter LOCA in “baking” mode. The performed analysis revealed differences in heat transfer modelling implemented in ASTEC and COCOSYS computer codes, which require further investigation to justify the correct approach for application to fusion facilities.

  19. Assessment of W7-X plasma vessel pressurisation in case of LOCA taking into account in-vessel components

    International Nuclear Information System (INIS)

    Urbonavičius, E.; Povilaitis, M.; Kontautas, A.

    2015-01-01

    Highlights: • Analysis of the vacuum vessel response to the LOCA in W7-X was performed using lumped-parameter codes COCOSYS and ASTEC. • Benchmarking of the results received with two codes provides more confidence in results and helps in identification of possible important differences in the modelling. • The performed analysis answered the questions set in the installed plasma vessel venting system during overpressure of PV in case of 40 mm diameter LOCA in “baking” mode. • Differences in time until opening the burst disk observed in ASTEC and COCOSYS results are caused by differences in heat transfer modelling. - Abstract: This paper presents the analysis of W7-X vacuum vessel response taking into account in-vessel components. A detailed analysis of the vacuum vessel response to the loss of coolant accident was performed using lumped-parameter codes COCOSYS and ASTEC. The performed analysis showed that the installed plasma vessel venting system prevents overpressure of PV in case of 40 mm diameter LOCA in “baking” mode. The performed analysis revealed differences in heat transfer modelling implemented in ASTEC and COCOSYS computer codes, which require further investigation to justify the correct approach for application to fusion facilities.

  20. Automated jitter correction for IR image processing to assess the quality of W7-X high heat flux components

    International Nuclear Information System (INIS)

    Greuner, H; De Marne, P; Herrmann, A; Boeswirth, B; Schindler, T; Smirnow, M

    2009-01-01

    An automated IR image processing method was developed to evaluate the surface temperature distribution of cyclically loaded high heat flux (HHF) plasma facing components. IPP Garching will perform the HHF testing of a high percentage of the series production of the WENDELSTEIN 7-X (W7-X) divertor targets to minimize the number of undiscovered uncertainties in the finally installed components. The HHF tests will be performed as quality assurance (QA) complementary to the non-destructive examination (NDE) methods used during the manufacturing. The IR analysis of an HHF-loaded component detects growing debonding of the plasma facing material, made of carbon fibre composite (CFC), after a few thermal cycles. In the case of the prototype testing, the IR data was processed manually. However, a QA method requires a reliable, reproducible and efficient automated procedure. Using the example of the HHF testing of W7-X pre-series target elements, the paper describes the developed automated IR image processing method. The algorithm is based on an iterative two-step correlation analysis with an individually defined reference pattern for the determination of the jitter.

  1. Review of the high heat flux testing as an integrated part of W7-X divertor development

    International Nuclear Information System (INIS)

    Greuner, H.; Boeswirth, B.; Boscary, J.; Friedrich, T.; Lavergne, C.; Linsmeier, Ch.; Schlosser, J.; Wiltner, A.

    2009-01-01

    The subject of the development of the WENDELSTEIN 7-X divertor is the manufacturing of approximately 900 plasma facing components (PFCs) that meet all requirements for reliable long pulse and long-term plasma operation. The actively cooled PFCs are made of CFC NB31 as plasma facing material bonded by Active Metal Casting (AMC) copper interlayer onto CuCrZr cooling structure. The pre-series activities integrated extensive high heat flux (HHF) testing to assess the industrial manufacturing. Tests were performed in the GLADIS facility under load conditions similar to those expected during operation of W7-X. The investigations focused on the improvement of fatigue resistance of the CFC/Cu bonding. The results of the last HHF test campaign demonstrated a significant enhancement of the CFC bonding quality due to the introduction of the AMC/Cu bi-layer technology. The results of the micro-chemical analyses (using EDX, AES, XPS and SIMS) of the CFC/Cu interface performed after 5000 cycles at 10 MW/m 2 confirmed its chemical stability. Far beyond the current available data about the expected lifetime of CFC-armoured PFCs, 10,000 cycles at 10 MW/m 2 were applied without any damages at the interface. The present design and manufacturing process of the tested PFCs fulfil all requirements for W7-X operation.

  2. Design of Tokamak plasma with high Tc superconducting coils

    International Nuclear Information System (INIS)

    Uchimoto, T.; Miya, K.; Yoshida, Y.; Yamada, T.

    1999-01-01

    This paper presents a design of tokamak plasma in light of how the small ignited tokamak is possible with use of the HTSC coils as plasma stabilizer. The same data base and formulas as ITER are here used and any innovative technology other than the HTSC stabilizing coils is not assumed. (author)

  3. Cooling device of superconducting coils. Dispositif de refroidissement de bobinages supraconducteurs

    Energy Technology Data Exchange (ETDEWEB)

    Duthil, R; Lottin, J C

    1985-08-30

    This device is rotating around an horizontal axis. The superconducting coils are contained in a cryogenic enclosure feeded in liquid helium forced circulation. They are related to an electric generator by electric mains each of them comprising a gas exchanger, and an exchanger-evaporator set between the cryogenic device and those exchangers. The exchanger-evaporator is aimed at dissipating the heat arriving by conductors connected to the superconducting coils. According to the invention, the invention includes an annular canalization with horizontal axis in which the connection conductors bathe in liquid helium.

  4. Application of superconducting coils to VAR control in electric power systems: a proposal

    International Nuclear Information System (INIS)

    Boenig, H.J.; Hassenzahl, W.V.

    1979-11-01

    During the last eight years, static VAR-control systems with thyristor-controlled, room-temperature reactors have been used in electrical systems for voltage control and system stabilization. In this proposal, we describe a new static VAR-control system that uses an asymmetrically controlled Graetz bridge and a superconducting dc coil. Preliminary studies indicate that the proposed system will have lower overall losses and that its capital cost and electrical characteristics are comparable to those of a conventional system. Three- and four-year programs for developing the electronic circuitry and superconducting coils for VAR control, culminating in the installation and testing of an approx. 40-MVAR system, are proposed

  5. Static Measurements on HTS Coils of Fully Superconducting AC Electric Machines for Aircraft Electric Propulsion System

    Science.gov (United States)

    Choi, Benjamin B.; Hunker, Keith R.; Hartwig, Jason; Brown, Gerald V.

    2017-01-01

    The NASA Glenn Research Center (GRC) has been developing the high efficiency and high-power density superconducting (SC) electric machines in full support of electrified aircraft propulsion (EAP) systems for a future electric aircraft. A SC coil test rig has been designed and built to perform static and AC measurements on BSCCO, (RE)BCO, and YBCO high temperature superconducting (HTS) wire and coils at liquid nitrogen (LN2) temperature. In this paper, DC measurements on five SC coil configurations of various geometry in zero external magnetic field are measured to develop good measurement technique and to determine the critical current (Ic) and the sharpness (n value) of the super-to-normal transition. Also, standard procedures for coil design, fabrication, coil mounting, micro-volt measurement, cryogenic testing, current control, and data acquisition technique were established. Experimentally measured critical currents are compared with theoretical predicted values based on an electric-field criterion (Ec). Data here are essential to quantify the SC electric machine operation limits where the SC begins to exhibit non-zero resistance. All test data will be utilized to assess the feasibility of using HTS coils for the fully superconducting AC electric machine development for an aircraft electric propulsion system.

  6. Pulsed field losses and intentional quenches of superconducting coils

    International Nuclear Information System (INIS)

    Kim, S.H.

    1983-01-01

    Pulsed field losses of several 5-20 kJ coils have been measured under triangular field variations. The conductors, developed as potential subcables of 25-50 kA cables, consist of Cu wires and NbTi strands with or without CuNi barriers. Losses of soft-soldered subcables are compared with those of well-compacted cables. The coils were quenched intentionally by pulsing the coils above the critical current to observe loss variations due to possible conductor damage. The method of measurements, and effects of soldering and compactness of the conductors on the pulsed field losses will be presented

  7. Experimental and theoretical investigation of mechanical disturbances in epoxy-impregnated superconducting coils

    International Nuclear Information System (INIS)

    Iwasa, Y.; Bobrov, E.S.; Tsukamoto, O.; Takaghi, T.; Fujita, H.; Massachusetts Inst. of Tech., Cambridge

    1985-01-01

    The theoretical correlation between shear stress and epoxy resin fracture developed in an earlier paper was verified experimentally using a series of epoxy-impregnated, thin-walled superconducting test coils. In test coils with both ends rigidly clamped, cracks occurred as transport current was increased; during a training sequence the test was terminated by a premature quench. Using acoustic emission and voltage signals, each premature quench was linked directly to a crack occurring near one of the ends. Test coils which had both ends unsupported, giving the winding freedom to expand radially, did not experience epoxy fracture and showed no premature quenches. (author)

  8. Development of superconducting poloidal field coils for medium and large size tokamaks

    International Nuclear Information System (INIS)

    Dittrich, H.-G.; Forster, S.; Hofmann, A.

    1983-01-01

    Large long pulse tokamak fusion experiments require the use of superconducting poloidal field (PF) coils. In the past not much attention has been paid to the development of such coils. Therefore a development programme has been initiated recently at KfK. In this report start with summarizing the relevant PF coil parameters of some medium and large size tokamaks presently under construction or design, respectively. The most important areas of research and development work are deduced from these parameters. Design considerations and first experimental results concerning low loss conductors, cooling concepts and structural components are given

  9. Program NICOLET to integrate energy loss in superconducting coils. [In FORTRAN for CDC-6600

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, H.F.

    1978-08-01

    A voltage pickup coil, inductively coupled to the magnetic field of the superconducting coil under test, is connected so its output may be compared with the terminal voltage of the coil under test. The integrated voltage difference is indicative of the resistive volt-seconds. When multiplied with the main coil current, the volt-seconds yield the loss. In other words, a hysteresis loop is obtained if the integrated voltage difference phi = ..integral delta..Vdt is plotted as a function of the coil current, i. First, time functions of the two signals phi(t) and i(t) are recorded on a dual-trace digital oscilloscope, and these signals are then recorded on magnetic tape. On a CDC-6600, the recorded information is decoded and plotted, and the hysteresis loops are integrated by the set of FORTRAN programs NICOLET described in this report. 4 figures.

  10. 1-GWh diurnal load-leveling superconducting magnetic energy storage system reference design. Appendix A: energy storage coil and superconductor

    International Nuclear Information System (INIS)

    Schermer, R.I.

    1979-09-01

    The technical aspects of a 1-GWh Superconducting Magnetic Energy Storage (SMES) coil for use as a diurnal load-leveling device in an electric utility system are presented. The superconductor for the coil is analyzed, and costs for the entire coil are developed

  11. Stability tests of the Westinghouse coil in the International Fusion Superconducting Magnet Test Facility

    International Nuclear Information System (INIS)

    Dresner, L.; Fehling, D.T.; Lubell, M.S.; Lue, J.W.; Luton, J.N.; McManamy, T.J.; Shen, S.S.; Wilson, C.T.

    1987-09-01

    The Westinghouse coil is one of three forced-flow coils in the six-coil toroidal array of the International Fusion Superconducting Magnet Test Facility at Oak Ridge National Laboratory. It is wound with an 18-kA, Nb 3 Sn/Cu, cable-in-conduit superconductor structurally supported by aluminum plates and cooled by 4-K, 15-atm supercritical helium. The coil is instrumented to permit measurement of helium temperature, pressure, and flow rate; structure temperature and strain; field; and normal zone voltage. A resistive heater has been installed to simulate nuclear heating, and inductive heaters have been installed to facilitate stability testing. The coil has been tested both individually and in the six-coil array. The tests covered charging to full design current and field, measuring the current-sharing threshold temperature using the resistive heaters, and measuring the stability margin using the pulsed inductive heaters. At least one section of the conductor exhibits a very broad resistive transition (resistive transition index = 4). The broad transition, though causing the appearance of voltage at relatively low temperatures, does not compromise the stability margin of the coil, which was greater than 1.1 J/cm 3 of strands. In another, nonresistive location, the stability margin was between 1.7 and 1.9 J/cm 3 of strands. The coil is completely stable in operation at 100% design current in both the single- and six-coil modes

  12. Results of the international Large Coil Task: a milestone for superconducting magnets in fusion power

    International Nuclear Information System (INIS)

    Dresner, L.; Fietz, W.A.; Gauss, S.

    1989-01-01

    The aim of the Large Coil Task (LCT) was to demonstrate the reliable operation of large superconducting toroidal field coils and to prove the design principles and fabrication techniques to be applied for the magnets in a tokamak experimental power reactor. This has been achieved by an international development effort involving the US DOE, EURATOM, JAERI and the Swiss government. Six different D-shaped test coils were separately designed, developed and constructed by the LCT participants, then extensively tested together in a compact toroidal array. Detailed information on coil design and manufacture and all test data were shared among the LCT participants. The full six-coil array tests were carried out in a continuous period from the beginning of 1986 until September 1987. Beside the originally planned tests to reach an 8 T design point performance, the tests went well beyond this goal, reaching 9 T peak field in each coil. The experiments also delineated the limits of operability and demonstrated the coil safety under abnormal conditions. For fusion application the transient a.c. field behaviour in the coils was also of great interest. Three of the coils have been tested in this respect and showed excellent performance, with loss values in agreement with the theoretical predictions. (author)

  13. Estimate of thermoelastic heat production from superconducting composites in pulsed poloidal coil systems

    International Nuclear Information System (INIS)

    Ballou, J.K.; Gray, W.H.

    1976-01-01

    In the design of the cryogenic system and superconducting magnets for the poloidal field system in a tokamak, it is important to have an accurate estimate of the heat produced in superconducting magnets as a result of rapidly changing magnetic fields. A computer code, PLASS (Pulsed Losses in Axisymmetric Superconducting Solenoids), was written to estimate the contributions to the heat production from superconductor hysteresis losses, superconductor coupling losses, stabilizing material eddy current losses, and structural material eddy current losses. Recently, it has been shown that thermoelastic dissipation in superconducting composites can contribute as much to heat production as the other loss mechanisms mentioned above. A modification of PLASS which takes into consideration thermoelastic dissipation in superconducting composites is discussed. A comparison between superconductor thermoelastic dissipation and the other superconductor loss mechanisms is presented in terms of the poloidal coil system of the ORNL Experimental Power Reactor design

  14. Thermographic observation of the divertor target plates in the stellarators W7-AS and W7-X

    International Nuclear Information System (INIS)

    Hildebrandt, D.; Gadelmeier, F.; Grigull, P.; McCormick, K.; Naujoks, D.; Suender, D.

    2003-01-01

    Thermography is applied on the stellarator W7-AS to monitor the thermal load of the recently installed divertor targets. A three dimensional numerical code was developed to evaluate power fluxes arriving at the targets from the measured temporal evolution of the surface temperature distribution. Values of the thermal conductivity of the used CFC-target material for all three directions are required for this evaluation and determined by observing the propagation of controlled heat pulses applied by an infrared laser. The evaluation of the thermographic measurements during plasma operation shows characteristic spatial and temporal features of the arrived heat fluxes. Significant features in high density regimes like plasma detachment from the divertor target plates or strongly enhanced localised plasma radiation (MARFE) has been observed by the installed infrared cameras. The implications of these observations for the thermographic system for W7-X are shortly addressed

  15. Design and operation of a novel Faraday-magnetometer using superconducting coils

    International Nuclear Information System (INIS)

    Koebler, U.; Deloie, F.

    1976-06-01

    This report gives a detailed description of the construction and operating procedures of a novel Faraday balance system which uses separate superconducting coils for field and field gradient. Special attention is given to all calibration problems, and hence to the limitations of accuracy with which magnetization measurements can be performed. (orig./WBU) [de

  16. Design of a low temperature superconducting coil to be applied to current regulators

    International Nuclear Information System (INIS)

    Garcia-Tabares, L.; Grau Carles, A

    1998-05-01

    We study the magnetic design and the cryogenic stability of a superconducting coil cooled with liquid helium, which works both in DC and AC modes. In DC mode, we obtain the maximum quench current; while in AC mode, we analyze Joule losses produced by the superconductor magnetization and the generation of eddy currents inside the copper matrix. (Author)

  17. W7-X vacuum and finite-β magnetic field structure resolved with the HINT 3D equilibrium code

    International Nuclear Information System (INIS)

    Hayashi, T.; Merkel, P.; Nuehrenberg, J.; Schwenn, U.

    1994-01-01

    The 3D equilibrium code HINT allows the direct investigation of finite-β effects on sizes and phases of islands in genuinely 3D configurations like the W7-X stellarator planned by the Max-Planck-Institut fuer Plasmaphysik in Germany. The code does not require the existence of nested flux surfaces. This, in contrast to the inverse formulation used in the VMEC code, leads to a considerably more complex computational goal. The HINT code combines some crucial features reducing the numerical problems and the computational effort to such an extent as to allow computation of 3D equilibria at finite-β with magnetic islands. The code is based on a two-step procedure: Starting from a given B and an initial pressure, the iteration technique for the pressure advancement is differencing in an artificial time with an explicit 4th order scheme, or - alternatively for resolving the island topology - field lines starting from all gridpoints are followed long enough to allow pressure equalization along these. B.∇p 0, for fixed B. In a second step, p is kept fixed and B is advanced with an artificial time for solving ∇p - jxB = 0 under the constraint of vanishing toroidal current J. The differential equations are discretized in space with 4th order difference approximations on an Eulerian grid spanned by a rectangular box whose toroidal rotation law follows the W7-X geometry. The two sub-iteration steps are repeated until the force balance is satisfied to an appropriate accuracy. The boundaries (where the boundary conditions are prescribed) are far enough away from the last closed magnetic surface, thus guaranteeing the motion of the plasma column not being constrained by the boundary conditions. Due to the stellarator symmetry in the toroidal direction only half of an equilibrium period is computed, using modified periodic boundary conditions guaranteeing the 4th order of the spatial discretization. (author) 5 refs., 4 figs

  18. Fabrication and testing of a superconducting coil: Phase 3 of the Maglev development program

    Energy Technology Data Exchange (ETDEWEB)

    Fife, A A; Lee, S; Tillotson, M [CTF Systems Inc., Port Coquitlam, BC (Canada)

    1989-03-01

    This report documents developmental research on superconducting magnet technology suitable for the levitation and propulsion units of the Canadian Maglev vehicle. The contract work involved the design, fabrication and testing of a racetrack coil fabricated using epoxy-impregnated windings of copper stabilized NbTi wire. The following results were achieved: successful fabrication and testing of a superconducting racetrack magnet with strength {gt} 400,000 A-turns integrated in a support frame; selection and characterization of cryogenic strain gauges; characterization of strain in solenoidal and racetrack superconducting magnets; design, fabrication and testing of high current persistent switches; and operation of superconducting magnets in persistent mode. The racetrack coil reached the design current after the third quench and short sample critical current after the eighth quench. This behavior is essentially identical to that observed with a superconducting solenoid fabricated during a previous phase. The strain measured perpendicular to the straight sides of the racetrack coil was proportional to the square of the energizing current. Persistent switches were fabricated, one type with low resistance (10{sup -2} ohm) and the other with high resistance (1.2 ohm) in their normal states. The low resistance switch could be operated in 1-Tesla fields with stabel characteristics up to about 800A drive current and the high resistance switch to 475A.

  19. Application of high-temperature superconducting coil for internal ring devices

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Yuichi [High Temperature Plasma Center, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8568 (Japan)]. E-mail: ogawa@ppl.k.u-tokyo.ac.jp; Morikawa, Junji [High Temperature Plasma Center, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8568 (Japan); Mito, Toshiyuki [National Institute for Fusion Science, Oroshi, Toki, Gifu 509-5292 (Japan); Yanagi, Nagato [National Institute for Fusion Science, Oroshi, Toki, Gifu 509-5292 (Japan); Iwakuma, Masataka [Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)

    2006-11-15

    A high-temperature superconducting (HTS) coil is applied for plasma confinement devices, where plasma is confined with a magnetic field of a floating HTS coil. The internal coil device mini-RT with a BSCCO tape has been constructed, in which the coil major radius and magnetomotive force are 0.15 m and 50 kA, respectively. The coil is cooled to 20 K with a helium gas by using a demountable transfer tube and check valve system. The coil current is directly excited by the external power supply with demountable electrodes. To reduce the heat load, the electrodes were cooled with liquid nitrogen. The levitation experiment of the HTS coil has been carried out. The position of the HTS coil is measured by laser sensors, and is feedback-controlled with the levitation coil current. We have succeeded in levitating the HTS coil during 1 h with accuracy of less than 20 {mu}m. The magnetic field strength near the internal coil is around 0.1 T, and a radio-frequency wave of 2.45 GHz is applied for the plasma production. At the floating condition of the HTS coil, a high-density plasma with more than 10{sup 17} m{sup -3}, which is higher than the cut-off density of a 2.45 GHz microwave, has been produced. A new device RT-1 with a major radius of 0.25 m and a magnetomotive force of 250 kA is under construction, and a persistent current has been demonstrated. The feasibility on YBCO tape is briefly discussed.

  20. Current control system for superconducting coils of LHD

    International Nuclear Information System (INIS)

    Chikaraishi, H.; Yamada, S.; Inoue, T.

    1996-01-01

    This paper introduce a coil current control system of the LHD. The main part of this system consists of two VME based real time computers and a risc based work station which are connected by optical fiber link. In this computer system, a coil current controller for steady state operation of LHD which based on a state variable control theory is installed. Also advanced current control scheme, which are now developing for dynamic current control in phase II operation of LHD, are introduced. (author)

  1. Current high-temperature superconducting coils and applications in Japan

    International Nuclear Information System (INIS)

    Matsushita, T.

    2000-01-01

    In Japan, four projects for the application of Bi-based superconducting magnets to practical apparatus are currently underway. These projects involve the development of an insert magnet for a 1 GHz nuclear magnetic resonance spectrometer, a magnet for a silicon single-crystal pulling apparatus, a magnet for a magnetic separation system, and a 1 T pulse magnet for a superconducting magnet energy storage system. For example, the magnet for the silicon single-crystal pulling apparatus is of the class with stored energy of 1 MJ to be operated at around 20 K. This review focuses on the present status of the development of these magnets, followed by a discussion of the problems of the present superconducting tapes that need to be overcome for future applications. (author)

  2. Mechanical design features of the MSU K-800 cyclotron superconducting coil

    International Nuclear Information System (INIS)

    Lawton, D.; Blosser, H.G.; Moskalik, J.M.; Stork, G.A.

    1984-01-01

    The winding of the K-800 cyclotron superconducting magnet coil was completed in late 1983. The windings consist of four separate coils (symmetrical large and small coils on each side of the median plane). The coils are wound in vertical layers in a spiral fashion. The large coils are 32 layers with 2329 total turns each (59,000 feet of wire) and the small coils are 32 layers with 1544 turns each (39,000 feet of wire). The spiral winding was achieved by supporting the first turn of a layer by a set of gradually increasing spacers with subsequent turns supported by previous turns. Winding was done on the 10 foot diameter table vertical lathe. The winding apparatus was mounted on the lathe's tool arm which had an automatic vertical feed to match the spiral path of the wire. The superconducting cable has a retangular cross section (with rounded corners) of dimentions .207 inches x .150 inches. Approximately 200 niobium titanium filaments are contained in a .04 inch x .06 inches copper insert that is soldered (50/50 lead tin) in a slot in the side of the copper conductor substrate

  3. Mechanical thermal and electric measurements on materials and components of the main coils of the Milan superconducting cyclotron

    International Nuclear Information System (INIS)

    Acerbi, E.; Rossi, L.

    1988-01-01

    The coils of the Milan Superconducting Cyclotron are the largest superconducting devices built up to now in Italy and constitute the first superconducting magnet for accelerator in Europe. Because of the large stored energy (more than 40 MJ), of the high stresses and of of the need of reliability, a lot of measurements were carried out as well on materials used for the coils, both on superconducting cable and structural materials, as on the main components of the coils and on two double pancakes prototypes (wound with full copper cable). In this paper the results on these measurements are reported and the results of tests on the prototypes are discussed. The aim is to provide an easy source of data for superconducting coils useful to verify calculations or to improve the performances

  4. Offset coil designs for superconducting magnets, a logical development

    International Nuclear Information System (INIS)

    Collins, T.

    1986-03-01

    Dipoles and quadrupoles for any new, large proton ring must be stronger, smaller and have better field shape (systematic error) than those used in the Doubler. The present two-shell designs are rigid in that the coils are too thin but cannot be relatively fatter without destroying the field quality. An examination of the coil shapes for dipoles and quadrupoles which produce perfect fields from a uniform current density shows clearly that our persistent use of a circular form for the inner surface of the coils is a poor approximation. When this is corrected by ''offsets'' there is a striking improvement both in the strength of fields and in the field quality. The same analysis makes clear that the efficient use of superconductor and the overall magnet size is determined by the perfect coil shapes. Any reasonable magnet will not differ significantly from the ideal for these parameters. This will be particularly helpful in setting design goals for very large quadrupoles. The offset two-shell dipole design preserves the mechanical features of the highly successful, resilient doubler magnets while greatly extending the performance

  5. Thermal aspects of a superconducting coil for fusion reactor

    International Nuclear Information System (INIS)

    Yeh, H.T.

    1975-01-01

    Computer models are used to simulate both localized and extensive thermal excursions in a large superconducting magnet for fusion reactor. Conditions for the failure of fusion magnet due to thermal excursion are delineated. Designs to protect the magnet against such thermal excursion are evaluated

  6. Design study of superconducting coils for the fusion DEMO plant at JAERI

    International Nuclear Information System (INIS)

    Isono, T.; Koizumi, N.; Okuno, K.; Kurihara, R.; Nishio, S.; Tobita, K.

    2006-01-01

    A design study of the TF coil for the fusion DEMO plant at JAERI is in progress. A major issue is to estimate the maximum fields generated by the TF coils for three tokamak options and two conductor options. Three tokamak options are proposed varying the aspect ratio and the role of the CS coil. Two kinds of conductors using advanced superconducting materials are candidates for the TF coils: Nb 3 Al and high temperature superconductor (HTS). In order to evaluate achievable magnetic fields, a simple method was adopted to calculate mechanical properties. The estimated maximum fields are 17-20 T by the HTS conductor and 16-17 T by the Nb 3 Al conductor. There is a possibility of a 0.7 T enhancement using grading of Nb 3 Al winding

  7. Design of MgB2 Superconducting coils for the Ignitor Experiment*

    Science.gov (United States)

    Grasso, G.; Penco, R.; Berta, S.; Coppi, B.; Giunchi, G.

    2009-11-01

    A feasibility study for the adoption of MgB2 superconducting cables for the largest (about 5 m in diameter) of the poloidal field coils of the Ignitor machine is being carried out. This initiative was prompted by the progress made in the fabrication of MgB2 long cables, and related superconducting magnets of relatively large dimensions. These magnets will be cryocooled at the operating temperature of 10-15 K that is compatible with the He-gas cryogenic cooling system of Ignitor as well as with the projected superconducting current density of the MgB2 material, at the magnetic field values (˜4-5 T) in which these coils are designed to operate. The optimal cable configuration has been identified that can provide an efficient cooling of the MgB2 conductors over times compatible with the machine duty cycles. MgB2 superconductors hold the promise of becoming suitable for high field magnets by appropriate doping of the material and of replacing gradually the normal conducting coils adopted, by necessity, in high field experiments. Therefore, an appropriate R&D program on the development of improved MgB2 material and related superconducting cabling options has been undertaken, involving different institutions.

  8. Serpentine Coil Topology for BNL Direct Wind Superconducting Magnets

    CERN Document Server

    Parker, Brett

    2005-01-01

    BNL direct wind technology, with the conductor pattern laid out without need for extra tooling (no collars, coil presses etc.) began with RHIC corrector production. RHIC patterns were wound flat and then wrapped on cylindrical support tubes. Later for the HERA-II IR magnets we improved conductor placement precision by winding directly on a support tube. To meet HERA-II space and field quality goals took sophisticated coil patterns, (some wound on tapered tubes). We denote such patterns, topologically equivalent to RHIC flat windings, "planar patterns." Multi-layer planar patterns run into trouble because it is hard to wind across existing turns and magnet leads get trapped at poles. So we invented a new "Serpentine" winding style, which goes around 360 degrees while the conductor winds back and forth on the tube. To avoid making solenoidal fields, we wind Serpentine layers in opposite handed pairs. With a Serpentine pattern each turn can have the same projection on the coil axis and integral field harmonics t...

  9. 10-kA pulsed power supply for superconducting coils

    International Nuclear Information System (INIS)

    Ehsani, M.; Fuja, R.E.; Kustom, R.L.

    1981-01-01

    A new 4-MW inductor-converter bridge (ICB) for supplying power to pulsed superconducting magnets is under construction at Argonne National Laoratory. This is a second-generation ICB built at Argonne Lab. The analytical, design, and control techniques developed for the first prototype have been used in the design of the new system. The paper presents the important considerations in the design of the new ICB. A brief description of the operation of the circuit is also given

  10. Cryogenics - Its influence on the selection of the ASTROMAG superconducting magnet coils

    Science.gov (United States)

    Green, M. A.

    1990-01-01

    ASTROMAG, a particle astrophysics experimental facility proposed for running alongside a Space Station, has a large superconducting magnet to analyze particles coming from deep space. Several types of magnets were investigated for use in the ASTROMAG central facility. The factors which influence the selection of the magnet coil design include: (1) the upper limit of particle momentum resolved (proportional to the integrated field) as a function of solid angle; (2)cryogenic design and its effect on cryogen lifetime for a given central facility mass; and (3) the overall cost of the magnet coils and cryostat. Four magnet types are analyzed in this paper. These include a simple two-coil solenoid (the baseline design),two disk coils at the ends of the helium tank, a two-coil toroid and a thin solenoid plus bucking coil. A balance must be struck between cryostat lifetime, total mass and the integrated field through the detectors. This balance tends to favor coils which are in the same vacuum vessel as the cryogen.

  11. Theoretical and experimental study on the magnetomechanical behavior of superconducting helical coils for a fusion reactor

    International Nuclear Information System (INIS)

    Takaghi, T.; Miya, K.; Yamada, H.; Takagi, T.

    1984-01-01

    The magnetomechanical behavior of superconducting helical coils for a magnetic fusion reactor was investigated experimentally and theoretically. Deformations of straight and torus type helical coils were caused due to static electromagnetic forces in the liquid helium cryostat and were analysed with the finite element computer code made here. Despite of a large scatter of experimental data due to a non-uniform friction force between the helical coil and the torus of stainless steel, the numerical results are very close to the mean value of the data. Numerical analysis of the force distribution acting on the helical coils was also performed for a Heliotron's coil system to characterize its nature. The force could be categorized conveniently as an extensional force, a tangential force and a toroidal force which correspond respectively to the kind of forces acting on toroidal field coils. Additionally, the effect of mechanical constraint on the magnetomechanical behavior is discussed and shows that the location of the constraint significantly affects the stress distributions in the coils. (orig.)

  12. Thermal anchoring of wires in large scale superconducting coil test experiment

    International Nuclear Information System (INIS)

    Patel, Dipak; Sharma, A.N.; Prasad, Upendra; Khristi, Yohan; Varmora, Pankaj; Doshi, Kalpesh; Pradhan, S.

    2013-01-01

    Highlights: • We addressed how thermal anchoring in large scale coil test is different compare to small cryogenic apparatus? • We did precise estimation of thermal anchoring length at 77 K and 4.2 K heat sink in large scale superconducting coil test experiment. • We addressed, the quality of anchoring without covering entire wires using Kapton/Teflon tape. • We obtained excellent results in temperature measurement without using GE Varnish by doubling estimated anchoring length. -- Abstract: Effective and precise thermal anchoring of wires in cryogenic experiment is mandatory to measure temperature in milikelvin accuracy and to avoid unnecessary cooling power due to additional heat conduction from room temperature (RT) to operating temperature (OT) through potential, field, displacement and stress measurement instrumentation wires. Instrumentation wires used in large scale superconducting coil test experiments are different compare to cryogenic apparatus in terms of unique construction and overall diameter/area due to errorless measurement in large time-varying magnetic field compare to small cryogenic apparatus, often shielded wires are used. Hence, along with other variables, anchoring techniques and required thermal anchoring length are entirely different in this experiment compare to cryogenic apparatus. In present paper, estimation of thermal anchoring length of five different types of instrumentation wires used in coils test campaign at Institute for Plasma Research (IPR), India has been discussed and some temperature measurement results of coils test campaign have been presented

  13. A 12 coil superconducting bumpy torus magnet facility for plasma research

    Science.gov (United States)

    Roth, J. R.; Holmes, A. D.; Keller, T. A.; Krawczonek, W. M.

    1972-01-01

    A summary is presented of the performance of the two-coil superconducting pilot rig which preceded the NASA Lewis bumpy torus. This pilot rig was operated for 550 experimental runs over a period of 7 years. The NASA Lewis bumpy torus facility consists of 12 superconducting coils, each with a 19 cm in diameter and capable of producing magnetic field strengths of 3.0 teslas on their axes. The magnets are equally spaced around a major circumference 1.52 m in diameter, and are mounted with the major axis of the torus vertical in a single vacuum tank 2.59 m in diameter. The design value of maximum magnetic field on the magnetic axis (3.0 teslas) was reached and exceeded. A maximum magnetic field of 3.23 teslas was held for a period of 60 minutes, and the coils did not go to normal. When the coils were charged to a maximum magnetic field of 3.35 teslas, the coil system was driven normal without damage to the facility.

  14. Evolution and results of LCT, international collaboration of superconducting coil development for fusion

    International Nuclear Information System (INIS)

    Shimamoto, Susumu

    1987-01-01

    This international collaboration has been promoted centering around the International Energy Agency since ten years ago. This work is that of advancing joint experiments on the equal footing by several countries gathering with large hardwares. As the result, unlike the international collaboration carried out so far, much experiences have been brought in. Now this work is going to be successfully completed. At this time, the realities of the international collaboration experienced through this work are reported while referring to a part of the technical results. Superconductors were found at the end of 1950s, and the technical development of superconducting coils has been advanced mainly for the equipment of high energy physics in foreign countries, while in Japan, for MHD electricity generation and magnetic levitation train. The TFTR (USA), JET (Euratom) and JT-60 (Japan) aiming at the attainment of critical plasma use normal conduction coils, but the agreement on the LCT project was signed in the autumn of 1977, which aims at the development of the superconducting coils for fusion experimental reactors. The development of coil manufacture in respective countries and the experiments in Japan and Euratom, some episode in the negotiation, the experiment on six coils and the results are reported. (Kako, I.)

  15. Protection for low current superconducting coils wound with insulated strand cable

    International Nuclear Information System (INIS)

    Satti, J.

    1980-09-01

    The insulated strand cable concept for winding of low current superconducting coil leads to an ideal quench protection by induction coupling. A superconducting secondary loop was made within a cable of a 6.2 Henry dipole coil. When quenching occurred, current was induced in the secondary strand above the critical value. The normal strand quenched the whole cable due to good thermal contact. The secondary loop works as a heater turned on as the wire becomes normal throughout the coil. With a well spread quench, the energy dissipation density is decreased thus preventing local burnout. The mechanism is possible because of close coupling that is present in the insulated cable as in bifilar winding. For the coil tested a 12 strand cable was used, thus a favorable 11 to 1 turn ratio was obtained for the primary to secondary. The superconductor in the secondary had a lower resistance until the critical current was achieved. A theoretical explanation is described for a simplified circuit. Test on the dipole coil with four individual shells showed that the one shell protected with the induced coupling heater always had a more rapid reduction of current. The induced coupling heater tested and explained in this paper works automatically and does not rely on mechanical or electrical devices

  16. 3D-computation of a thermal process in a superconducting coil

    International Nuclear Information System (INIS)

    Netter, D.; Leveque, J.; Rezzoug, A.; Caron, J.P.; Sargos, F.M.

    1995-01-01

    This study deals with the resistive zone propagation in a superconducting coil during a quench, taking into account both the flux density distribution and the anisotropy of the thermal parameters. A Finite Difference Method is used to solve the heat diffusion equation and the flux density is calculated by means of a semi-analytical method. The 3-D model is suitable to describe the quench of thick coils and it can be applied to the study of thermal stability. As an application, a 10 kJ-solenoid is studied

  17. Design and fabrication of forced-flow superconducting poloidal coils for the Large Helical Device

    International Nuclear Information System (INIS)

    Nakamoto, K.; Yamamoto, T.; Mizumaki, S.; Yamakoshi, T.; Kanai, Y.; Yamamoto, K.; Wachi, Y.; Ushijima, M.; Yoshida, T.; Kai, T.; Takahata, K.; Yamamoto, J.; Satow, T.; Motojima, O.

    1995-01-01

    Three pairs of superconducting poloidal coils for the LHD (Large Helical Device) have been designed and fabricated using NbTi/Cu cable-in-conduit (CIC) conductors cooled with forced-flow supercritical helium (SHE). In the LHD poloidal coils, high field accuracy as well as high reliability are required. To meet these requirements, detailed field and structural analyses have been performed and key parameters including winding pattern and size and locations of conductor joints have been determined. Compact conductor joint, where NbTi filaments are directly bonded, has also been developed using the solid state bonding technique. (orig.)

  18. Magnetic levitation using high temperature superconducting pancake coils as composite bulk cylinders

    International Nuclear Information System (INIS)

    Patel, A; Hopkins, S C; Baskys, A; Glowacki, B A; Kalitka, V; Molodyk, A

    2015-01-01

    Stacks of superconducting tape can be used as composite bulk superconductors for both trapped field magnets and for magnetic levitation. Little previous work has been done on quantifying the levitation force behavior between stacks of tape and permanent magnets. This paper reports the axial levitation force properties of superconducting tape wound into pancake coils to act as a composite bulk cylinder, showing that similar stable forces to those expected from a uniform bulk cylinder are possible. Force creep was also measured and simulated for the system. The geometry tested is a possible candidate for a rotary superconducting bearing. Detailed finite element modeling in COMSOL Multiphysics was also performed including a full critical state model for induced currents, with temperature and field dependent properties and 3D levitation force models. This work represents one of the most complete levitation force modeling frameworks yet reported using the H-formulation and helps explain why the coil-like stacks of tape are able to sustain levitation forces. The flexibility of geometry and consistency of superconducting properties offered by stacks of tapes, make them attractive for superconducting levitation applications. (paper)

  19. Analysis of an HTS coil for large scale superconducting magnetic energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Young; Lee, Se Yeon; Choi, Kyeong Dal; Park, Sang Ho; Hong, Gye Won; Kim, Sung Soo; Kim, Woo Seok [Korea Polytechnic University, Siheung (Korea, Republic of); Lee, Ji Kwang [Woosuk University, Wanju (Korea, Republic of)

    2015-06-15

    It has been well known that a toroid is the inevitable shape for a high temperature superconducting (HTS) coil as a component of a large scale superconducting magnetic energy storage system (SMES) because it is the best option to minimize a magnetic field intensity applied perpendicularly to the HTS wires. Even though a perfect toroid coil does not have a perpendicular magnetic field, for a practical toroid coil composed of many HTS pancake coils, some type of perpendicular magnetic field cannot be avoided, which is a major cause of degradation of the HTS wires. In order to suggest an optimum design solution for an HTS SMES system, we need an accurate, fast, and effective calculation for the magnetic field, mechanical stresses, and stored energy. As a calculation method for these criteria, a numerical calculation such as an finite element method (FEM) has usually been adopted. However, a 3-dimensional FEM can involve complicated calculation and can be relatively time consuming, which leads to very inefficient iterations for an optimal design process. In this paper, we suggested an intuitive and effective way to determine the maximum magnetic field intensity in the HTS coil by using an analytic and statistical calculation method. We were able to achieve a remarkable reduction of the calculation time by using this method. The calculation results using this method for sample model coils were compared with those obtained by conventional numerical method to verify the accuracy and availability of this proposed method. After the successful substitution of this calculation method for the proposed design program, a similar method of determining the maximum mechanical stress in the HTS coil will also be studied as a future work.

  20. Analysis of an HTS coil for large scale superconducting magnetic energy storage

    International Nuclear Information System (INIS)

    Lee, Ji Young; Lee, Se Yeon; Choi, Kyeong Dal; Park, Sang Ho; Hong, Gye Won; Kim, Sung Soo; Kim, Woo Seok; Lee, Ji Kwang

    2015-01-01

    It has been well known that a toroid is the inevitable shape for a high temperature superconducting (HTS) coil as a component of a large scale superconducting magnetic energy storage system (SMES) because it is the best option to minimize a magnetic field intensity applied perpendicularly to the HTS wires. Even though a perfect toroid coil does not have a perpendicular magnetic field, for a practical toroid coil composed of many HTS pancake coils, some type of perpendicular magnetic field cannot be avoided, which is a major cause of degradation of the HTS wires. In order to suggest an optimum design solution for an HTS SMES system, we need an accurate, fast, and effective calculation for the magnetic field, mechanical stresses, and stored energy. As a calculation method for these criteria, a numerical calculation such as an finite element method (FEM) has usually been adopted. However, a 3-dimensional FEM can involve complicated calculation and can be relatively time consuming, which leads to very inefficient iterations for an optimal design process. In this paper, we suggested an intuitive and effective way to determine the maximum magnetic field intensity in the HTS coil by using an analytic and statistical calculation method. We were able to achieve a remarkable reduction of the calculation time by using this method. The calculation results using this method for sample model coils were compared with those obtained by conventional numerical method to verify the accuracy and availability of this proposed method. After the successful substitution of this calculation method for the proposed design program, a similar method of determining the maximum mechanical stress in the HTS coil will also be studied as a future work

  1. Superconductive coil characterization for next dipoles and quadrupoles generation

    CERN Document Server

    Khalil, Malathe

    2016-01-01

    The LHC is the most sophisticated scientific machine ever built as a device that allows the scientists to explore the universe and its origin. Scientists from all over the world are working to upgrade the LHC to open the door for new physics. HL-LHC (high luminosity LHC) project is the core project at CERN which was approved in 2013 by CERN’s council. In order to increase the integrated luminosity up to 3000 fb-1 within this decade. To do so it is crucial to design cutting edge superconducting magnets that can elevate the magnetic field up to 20T, which is Nb$_{3}$Sn. However this material is brittle when it functions as superconductor, which makes it hard to be used as a cold magnet. So in this report the fabrication of 10 stacks of Nb$_{3}$Sn superconducting multifilament wires was investigated as well as primary test using experimental setup and creating material model for Nb$_{3}$Sn with the finite element analysis [ANSYS] is carried out.

  2. Influence of dump voltage and allowable temperature rise on stabilizer requirements in superconducting coils

    International Nuclear Information System (INIS)

    Schwenterly, S.W.

    1988-01-01

    A superconducting winding must have enough stabilizer to satisfy two sets of criteria. During normal operation, the amount of stabilizer must be large enough either to make the coil unconditionally stable or to give a certain desired stability margin. Once a dump occurs, the amount of stabilizer must be large enough to carry the current without generating excessive dump voltages or allowing the winding to exceed a certain maximum temperature (and maximum pressure, in the case of force-cooled coils). The voltage criterion often dominates for very large coil systems, but it is frequently ignored in initial design studies. This paper gives some simple relations between the dump voltage and the stored energy, temperature rise, and coil geometry that are useful in scooping the required amount of stabilizer. Comparison with some recently proposed fusion magnet system designs indicates that excessive dump voltages could result in some cases. High-temperature superconductors may require more stabilizer than the conventional alloys. Calculations with simple model coil systems indicate how trade-offs between various coil parameters affect the dump voltage. 12 refs., 1 fig., 1 tab

  3. Analysis of transmission efficiency of the superconducting resonance coil according the materials of cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yu Kyeong; Hwang, Jun Won; Choi, Hyo Sang [Chosun University, Gwangju (Korea, Republic of)

    2016-03-15

    The wireless power transfer (WPT) system using a magnetic resonance was based on magnetic resonance coupling of the transmission and the receiver coils. In these system, it is important to maintain a high quality-factor (Q-factor) to increase the transmission efficiency of WPT system. Our research team used a superconducting coil to increase the Q-factor of the magnetic resonance coil in WPT system. When the superconductor is applied in these system, we confirmed that transmission efficiency of WPT system was higher than normal conductor coil through a preceding study. The efficiency of the transmission and the receiver coil is affected by the magnetic shielding effect of materials around the coils. The magnetic shielding effect is dependent on the type, thickness, frequency, distance, shape of materials. Therefore, it is necessary to study the WPT system on the basis of these conditions. In this paper, the magnetic shield properties of the cooling system were analyzed using the High-Frequency Structure Simulation (HFSS, Ansys) program. We have used the shielding materials such as plastic, aluminum and iron, etc. As a result, when we applied the fiber reinforced polymer (FRP), the transmission efficiency of WPT was not affected because electromagnetic waves went through the FRP. On the other hand, in case of a iron and aluminum, transmission efficiency was decreased because of their electromagnetic shielding effect. Based on these results, the research to improve the transmission efficiency and reliability of WPT system is continuously necessary.

  4. Conceptual designs of 50 kA 20 MJ superconducting ohmic heating coils

    International Nuclear Information System (INIS)

    Singh, S.K.; Murphy, J.H.; Janocko, M.A.; Haller, H.E.; Litz, D.C.; Eckels, P.W.; Rogers, J.D.; Thullen, P.

    1979-01-01

    Two designs of 20 Mj superconducting coils are described which were developed to demonstrate the feasibility of an ohmic heating system. NbTi and Nb;sub 3;Sn superconductors were considered for both 7 tesla and 9 tesla maximum fields. Cabled and braided conductors were investigated and the braided conductor is identified as the best alternative due to its high operating current densities and because of its porosity. The coils are designed to be cryostable for bipolar operation from +7 tesla to -7 tesla and from +9 tesla to -9 tesla maximum fields within 1 sec. The structural design addresses the distribution of structure and structural materials used in the pulsed field environment. Immersion cooled (pool boil) and forced flow cooled coils are described. 2 refs

  5. Alternative power supply and dump resistor connections for similar, mutually coupled, superconducting coils

    International Nuclear Information System (INIS)

    Owen, E.W.; Shimer, W.; Wang, S.T.

    1983-01-01

    Alternative methods of connecting similar mutually coupled coils to their power supplies and dump resistors are investigated. The circuits are evaluated for both operating and fault conditions. The factors considered are the voltage to ground during a dump, short circuits, open circuits, quenches, and failure of the protection system to detect a quench. Of particular interest are the currents induced in coils that remain superconducting when one or more coils quench. The alternative connections include combined power supplies, individual dump resistors, combined resistors and series and parallel dump resistors. A new circuit that contains ''coupling'' resistors is proposed. The coupling resistors do not affect normal fast dumps but reduce the peak induced currents while also reducing the energy rating of the dump resistors. Another novel circuit, the series circuit with diodes, is discussed. The MFTF-B central-cell solenoids are used as an example

  6. Alternative power supply and dump resistor connections for similar, mutally coupled, superconducting coils

    International Nuclear Information System (INIS)

    Owen, E.W.; Shimer, D.W.; Wang, S.T.

    1983-01-01

    Alternative methods of connecting similar mutually coupled coils to their power supplies and dump resistors are investigated. The circuits are evaluated for both operating and fault conditions. The factors considered are the voltage to ground during a dump, short circuits, open circuits, quenches, and failure of the protection system to detect a quench. Of particular interest are the currents induced in coils that remain superconducting when one or more coils quench. The alternative connections include combined power supplies, individual dump resistors, combined resistors and series and parallel dump resistors. A new circuit that contains coupling resistors is proposed. The coupling resistors do not affect normal fast dumps but reduce the peak induced currents while also reducing the energy rating of the dump resistors. Another novel circuit, the series circuit with diodes, is discussed. The MFTF-B central-cell solenoids are used as an example

  7. Coil protection for a utility scale superconducting magnetic energy storage plant

    International Nuclear Information System (INIS)

    Loyd, R.J.; Schoenung, S.M.; Rogers, J.D.; Hassenzahl, W.V.; Purcell, J.R.

    1986-01-01

    Superconducting Magnetic Energy Storage (SMES) is proposed for electric utility load leveling. Attractive costs, high diurnal energy efficiency (≥ 92%), and rapid response are advantages relative to other energy storage technologies. Recent industry-led efforts have produced a conceptual design for a 5000 MWh/1000 MW energy storage plant which is technically feasible at commercially attractive estimated costs. The SMES plant design includes a protection system which prevents damage to the magnetic coil if events require a rapid discharge of stored energy. This paper describes the design and operation of the coil protection system, which is primarily passive and uses the thermal capacity of the coil itself to absorb the stored electromagnetic energy

  8. A 25 kA, 2T, 78 kJ, 52 litre superconducting test coil. Strength calculations and construction

    NARCIS (Netherlands)

    ten Kate, Herman H.J.; Holtslag, A.H.M.; Knoben, J.; Steffens, H.A.; van de Klundert, L.J.M.

    1983-01-01

    Within the scope of our research program for a 25 kA superconducting rectifier, we have built a 25 kA s.c. coil being a single layer solenoid with a bore of 0.45 meter and a volume of 52 litre. The starting point for the design was to avoid any metallic structural material. This unique coil consists

  9. Analysis of the electrodynamics of subcable current distribution in the superconducting POLO coil cable

    International Nuclear Information System (INIS)

    Sihler, C.; Heller, R.; Maurer, W.; Ulbricht, A.; Wuechner, F.

    1995-10-01

    Unexpected ramp rate limitations (RRL) found in superconducting magnets during the development of magnet systems can be attributed to a current imbalance amongst the cabled strands which leads to a lower than expected quench current. In superconducting magnets the current distribution in the cable during ramping depends mainly on the electromagnetic properties of the system. A detailed analysis of principle causes for RRL phenomena was performed with a model for one half of the POLO coil considering the complete inductance matrix of the cable and the fact that all turns are mutually coupled. The main results of these calculations are that unequal contact resistances can not be responsible for RRL phenomena in coils with parameters comparable to those of the POLO coil and that already minor geometrical disturbances in the cable structure can lead to major and lasting imbalances in the current distribution of cables with insulated and non-insulated strands. During the POLO experiment the half-coil model was employed to get a better understanding of the measured compensated subcable voltages during quench. The good agreement of the calculated and measured results demonstrates the validity of the model for RRL analyses. (orig.)

  10. Potential minimum cost of electricity of superconducting coil tokamak power reactors

    International Nuclear Information System (INIS)

    Reid, R.L.; Peng, Y-K. M.

    1989-01-01

    The potential minimum cost of electricity (COE) for superconducting tokamak power reactors is estimated by increasing the physics (confinement, beta limit, bootstrap current fraction) and technology [neutral beam energy, toroidal field (TF) coil allowable stresses, divertor heat flux, superconducting coil critical field, critical temperature, and quench temperature rise] constraints far beyond those assumed for ITER until the point of diminishing returns is reached. A version of the TETRA systems code, calibrated with the ITER design and modified for power reactors, is used for this analysis, limiting this study to reactors with the same basic device configuration and costing algorithms as ITER. A minimum COE is reduced from >200 to about 80 mill/kWh when the allowable design constraints are raised to 2 times those of ITER. At 4 times the ITER allowables, a minimum COE of about 60 mill/kWh is obtained. The corresponding tokamak has a major radius of approximately 4 m, a plasma current close to 10 MA, an aspect ratio of 4, a confinement H- factor ≤3, a beta limit of approximately 2 times the first stability regime, a divertor heat flux of about 20 MW/m 2 , a Β max ≤ 18 T, and a TF coil average current density about 3 times that of ITER. The design constraints that bound the minimum COE are the allowable stresses in the TF coil, the neutral beam energy, and the 99% bootstrap current (essentially free current drive). 14 refs., 4 figs., 2 tabs

  11. Experiment study on an inductive superconducting fault current limiter using no-insulation coils

    Science.gov (United States)

    Qiu, D.; Li, Z. Y.; Gu, F.; Huang, Z.; Zhao, A.; Hu, D.; Wei, B. G.; Huang, H.; Hong, Z.; Ryu, K.; Jin, Z.

    2018-03-01

    No-insulation (NI) coil made of 2 G high temperature superconducting (HTS) tapes has been widely used in DC magnet due to its excellent performance of engineering current density, thermal stability and mechanical strength. However, there are few AC power device using NI coil at present. In this paper, the NI coil is firstly applied into inductive superconducting fault current limiter (iSFCL). A two-winding structure air-core iSFCL prototype was fabricated, composed of a primary copper winding and a secondary no-insulation winding using 2 G HTS coated conductors. Firstly, in order to testify the feasibility to use NI coil as the secondary winding, the impedance variation of the prototype at different currents and different cycles was tested. The result shows that the impedance increases rapidly with the current rises. Then the iSFCL prototype was tested in a 40 V rms/ 3.3 kA peak short circuit experiment platform, both of the fault current limiting and recovery property of the iSFCL are discussed.

  12. Requirements for accuracy of superconducting coils in the Large Helical Device

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, K; Yanagi, N; Ji, H; Kaneko, H; Ohyabu, N; Satow, T; Morimoto, S; Yamamoto, J; Motojima, O [National Inst. for Fusion Science, Chikusa, Nagoya (Japan); LHD Design Group

    1993-01-01

    Irregular magnetic fields resonate with the rational surface of the magnetic confinement systems, form magnetic islands and ergodic layers, and destruct the plasma confinement. To avoid this confinement destruction the requirement of an accuracy of 10[sup -4] in the magnetic field is adopted as the magnetic-accuracy design criterion for the LHD machine. Following this criterion the width of the undesirable magnetic island is kept less than one tenth of the plasma radius. The irregular magnetic field from the superconducting (SC) helical and poloidal coils is produced by winding irregularity, installing irregularity, cooling-down deformations and electromagnetic deformations. The local irregularities such as feeders, layer connections, adjacent-conductor connections of the coils also produce an error field. The eddy currents on the supporting shell structure of SC coils, the cryostat, etc. are also evaluated. All irregular effects are analyzed using Fourier decomposition and field mapping methods for the LHD design, and it is confirmed that the present design of the superconducting coil system satisfies the design criterion for these field irregularities. (orig.).

  13. Comparison of silicon drift detectors made by Amptek and PNDetectors in application to the PHA system for W7-X

    Directory of Open Access Journals (Sweden)

    Krawczyk Natalia

    2016-12-01

    Full Text Available The paper presents comparison of two silicon drift detectors (SDD, one made by Amptek, USA, and the second one by PNDetector, Germany, which are considered for a soft X-ray diagnostic system for W7-X. The sensitive area of the first one is 7 mm2 × 450 μm and the second one is 10 mm2 × 450 μm. The first detector is cooled by a double-stage Peltier element, while the second detector is cooled by single-stage Peltier element. Each one is equipped with a field-effect transistor (FET. In the detector from Amptek, the FET is mounted separately, while in the detector from PNDetector, the FET is integrated on the chip. The nominal energy resolution given by the producers of the first and the second one is 136 eV@5.9 keV (at -50°C and 132 eV@5.9 keV (at -20°C, respectively. Owing to many advantages, the investigated detectors are good candidates for soft X-ray measurements in magnetic confinement devices. They are suitable for soft X-ray diagnostics, like the pulse height analysis (PHA system for the stellarator Wendelstein 7-X, which has been developed and manufactured at the Institute of Plasma Physics and Laser Microfusion (IPPLM, Warsaw, in collaboration with the Max Planck Institute for Plasma Physics (IPP, Greifswald. The diagnostic is important for the measurements of plasma electron temperature, impurities content, and possible suprathermal tails in the spectra. In order to choose the best type of detector, analysis of technical parameters and laboratory tests were done. Detailed studies show that the most suitable detector for the PHA diagnostics is the PNDetector.

  14. Pool-cooled superconducting coils: past, present and future

    International Nuclear Information System (INIS)

    Thome, R.J.; Dawson, A.M.

    1985-08-01

    An overview of large magnet systems which have been studied, constructed, or operated in the last 12 years is presented and shows a substantial advance in overall current density, stored energy, and magnet complexity. The preferable coolant mode for very large magnets is still a bath of helium I, but it is clear that other coolant modes are gaining acceptance. The data base for design using stability criteria dependent on transients has expanded to the point where the risk is often acceptable, compared to the lower current density, low risk, steady state stability criteria which launched large superconducting magnet technology. The limitation imposed by structure and protection on increasing overall current density in large magnets is discussed and a simple model is used to illustrate the extreme requirements imposed on a winding without direct helium contact. The latter implies that a significant technological step is required before conduction cooling or indirect cooling will be used in the large magnets envisioned for the future and that helium contact with the conductor will remain the key ingredient for risk reduction in large magnet design

  15. Investigation of transient electrical, magnetic, and mechanical phenomena in large superconducting magnet coils

    International Nuclear Information System (INIS)

    Sihler, C.

    1996-07-01

    The progress in the field of technology for superconducting magnets led to the necessity of transferring existing calculation methods from electrical power engineering, modifying these tools to satisfy the boundary conditions for superconducting magnets, and also developing new calculation methods for special purposes. In this work suitable calculation methods are elaborated. Their validity and applicability is demonstrated in employing these scientific engineering tools to actual developments of the Forschungszentrum Karlsruhe. In detail this work deals with: 1. calculating eddy current and force densities in the conducting environment of a superconducting magnet or magnet system. 2. the effects of eddy current forces in experimental engineering; 3. transient effects of electrical surges acting on new coil designs; and 4. the electrical and magnetic properties of superconducting cables. Especially, the magnetic properties can lead to an inhomogeneous current distribution in the cable and, thus, to a considerable reduction of the current carrying capacity of the whole magnet. These investigations demonstrate that a detailed analysis of electrodynamic phenomena is indispensable in order to find the optimum technical way to make use of the physical potential of superconductivity. (orig./MM) [de

  16. The superconducting busbar system of Wendelstein 7-X

    International Nuclear Information System (INIS)

    Stache, Kerstin; Kerl, F.; Sapper, J.; Sombach, B.; Wegener, L.

    2003-01-01

    The superconducting magnet system of the stellarator Wendelstein 7-X (W7-X) consists of 50 non-planar and 20 planar coils grouped in five periodic modules. Ten coils of a given type of non-planar and planar coils will always be connected electrically in series with nominal currents ranging up to 18 kA. Because of the 5-fold symmetry five busbar systems are to be routed. Electrical connection of the busbar system will require 184 disconnectable joints with a resistance below 5 nΩ. The paper describes the design features of the busbar systems and their installation in the stellarator. Requirements for the design and qualification of the disconnectable joints will be pointed out

  17. Model of vortex dynamics in superconducting films in two-coil measurements of the coherence length

    Science.gov (United States)

    Lemberger, Thomas; Loh, Yen Lee

    In two-coil measurements on superconducting films, a magnetic field from a small coil is applied to the center of the film. When the amplitude of the ac field is increased, the film undergoes a transition from the ``Meissner'' state to a state with vortices and antivortices. Ultimately, the vortex density matches the applied magnetic field and field screening is negligible. Experimentally, the field at the transition is related to the superconducting coherence length, although a full theory of the relationship is lacking. We show that the mutual inductance between drive and pickup coils, on opposite sides of the film, as a function of ac field amplitude is well-described by a phenomenological model in which vortices and antivortices appear together in the film at the radius where the induced supercurrent is strongest, and then they move through a landscape of moderately strong vortex pinning sites. Work at OSU supported by DOE-Basic Energy Sciences through Grant No. FG02-08ER46533.

  18. Characteristics of persistent-current mode of HTS coil on superconducting electromagnet

    International Nuclear Information System (INIS)

    Lee, C.Y.; Kim, J.; Han, Y.J.; Kang, B.; Chung, Y.D.; Yoon, Y.S.; Chu, S.Y.; Hwang, Y.J.; Jo, H.C.; Jang, J.Y.; Ko, T.K.

    2011-01-01

    The levitation gap of an electromagnetic suspension (EMS) system affects the current decay rate of superconducting electromagnet. The presence of iron core provides a significant benefit in the PCM performance of SC coil. The increased levitation gap of the EMS model with the SC-EM could negatively affect the design of SC-EM operated in PCM. This paper investigates the way in which the levitation gap of an electromagnetic suspension (EMS) system affects the current decay rate of superconducting electromagnet (SC-EM) operated in persistence-current mode (PCM). Using inductance analyzed from the magnetic circuit of an EMS model, the current decay rate caused by the variation in the levitation gap was simulated. In order to experimentally verify the simulation results, we fabricated a small-scale EMS model with SC coil operated in PCM and measured the current decay rates at different levitation gaps. The result showed that the presence of iron core provides a significant benefit in the PCM performance of SC coil, but the benefit decreased as the levitation gap increases. This study revealed that the increased levitation gap of the EMS model with the SC-EM could negatively affect the design of SC-EM operated in PCM.

  19. A novel approach to quench detection for high temperature superconducting coils

    International Nuclear Information System (INIS)

    Song, W.J.; Fang, X.Y.; Fang, J.; Wei, B.; Hou, J.Z.; Liu, L.F.; Lu, K.K.; Li, Shuo

    2015-01-01

    Highlights: • We proposed a novel quench detection method mainly based on phase for HTS coil. • We showed theory model and numerical simulation system by LabVIEW. • Experiment results are showed and analyzed. • Little quench voltage will cause obvious change on phase. • The approach can accurately detect quench resistance voltage in real-time. - Abstract: A novel approach to quench detection for high temperature superconducting (HTS) coils is proposed, which is mainly based on phase angle between voltage and current of two coils to detect the quench resistance voltage. The approach is analyzed theoretically, verified experimentally and analytically by MATLAB Simulink and LabVIEW. An analog quench circuit is built on Simulink and a quench alarm system program is written in LabVIEW. Experiment of quench detection is further conducted. The sinusoidal AC currents ranging from 19.9 A to 96 A are transported to the HTS coils, whose critical current is 90 A at 77 K. The results of analog simulation and experiment are analyzed and they show good consistency. It is shown that with the increase of current, the phase undergoes apparent growth, and it is up to 60° and 15° when the current reaches critical value experimentally and analytically, respectively. It is concluded that the approach proposed in this paper can meet the need of precision and quench resistance voltage can be detected in time.

  20. A novel approach to quench detection for high temperature superconducting coils

    Energy Technology Data Exchange (ETDEWEB)

    Song, W.J., E-mail: songwenjuan@bjtu.edu.cn [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); China Electric Power Research Institute, Beijing (China); Fang, X.Y. [Department of Electrical and Computer Engineering, University of Victoria, PO Box 1700, STN CSC, Victoria, BC V8W 2Y2 (Canada); Fang, J., E-mail: fangseer@sina.com [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); Wei, B.; Hou, J.Z. [China Electric Power Research Institute, Beijing (China); Liu, L.F. [Guangzhou Metro Design & Research Institute Co., Ltd, Guangdong (China); Lu, K.K. [School of Electrical Engineering, Beijing Jiaotong University, Beijing (China); Li, Shuo [College of Information Science and Engineering, Northeastern University, Shenyang (China)

    2015-11-15

    Highlights: • We proposed a novel quench detection method mainly based on phase for HTS coil. • We showed theory model and numerical simulation system by LabVIEW. • Experiment results are showed and analyzed. • Little quench voltage will cause obvious change on phase. • The approach can accurately detect quench resistance voltage in real-time. - Abstract: A novel approach to quench detection for high temperature superconducting (HTS) coils is proposed, which is mainly based on phase angle between voltage and current of two coils to detect the quench resistance voltage. The approach is analyzed theoretically, verified experimentally and analytically by MATLAB Simulink and LabVIEW. An analog quench circuit is built on Simulink and a quench alarm system program is written in LabVIEW. Experiment of quench detection is further conducted. The sinusoidal AC currents ranging from 19.9 A to 96 A are transported to the HTS coils, whose critical current is 90 A at 77 K. The results of analog simulation and experiment are analyzed and they show good consistency. It is shown that with the increase of current, the phase undergoes apparent growth, and it is up to 60° and 15° when the current reaches critical value experimentally and analytically, respectively. It is concluded that the approach proposed in this paper can meet the need of precision and quench resistance voltage can be detected in time.

  1. Cool-down performance of CICC superconducting coils for the CHMFL

    Science.gov (United States)

    Xie, Y.; Li, J.; Ouyang, Z. R.

    2017-10-01

    A hybrid magnet composed of a water-cooled magnet and a superconducting magnet was developed at the High Magnetic Field Laboratory of the Chinese Academy of Sciences. The superconducting coils made of Nb3Sn CICC were cooled by the forced flow of supercritical helium at 4.5 K. The paper presents the cryogenic system framework, and reports the characteristics of the supercritical helium in a cable-in-conduit conductor (CICC), including the friction factor change during the cooling process, the heat transfer coefficient from 4.6 K to 6.8 K, and the helium mass flow rate distribution. After the 23-day cooling process, the temperature reached 4.5 K. The operation process was introduced in the paper.

  2. Quench protection system for 1 MJ superconducting magnet coil for SMES Project at VECC, Kolkata

    International Nuclear Information System (INIS)

    Thakur, S.K.; Bera, A.; Kumar, Y.; Bhunia, U.; Pradhan, J.; Saha, S.

    2012-01-01

    This paper describes the indigenous development of a system which is used for quench detection, protection and monitoring the parameters of superconducting coil of superconducting magnetic energy storage (SMES) system. Resistive voltage measurement method is used for detecting the quench. The voltage across each current lead is also monitored and over voltage across the current lead is detected by comparing it with a set voltage limit. By using isolation amplifier and timer circuit, false quench trigging due to noise and spikes are minimized. If quench is detected a relay operated to turn-off the SMES power supply followed by the release of stored energy of the magnet to the external dump resistance by closing a switch. (author)

  3. Development of actively cooled windows for plasma observation during quasi-continuous operation of the W7-X stellarator

    International Nuclear Information System (INIS)

    Konig, R.; Grosser, K.; Hildebrandt, D.; Pasch, E.; Werner, T.; Klinger, T.; Ogorodnikova, O.

    2005-01-01

    With the stellarator W7-X a step to quasi-continuous plasma operation will be made. The cooling system of the machine is designed such that two 30 min discharges can be run per day. Right from the start of operation 10 MW of ECRH heating power will be available for quasi-continuous operation. A working group 'Plasma Facing Optical Components' has been formed which presently concentrates on the development of water cooled windows for UV/VR/IR periscopes which can withstand the expected maximum heat loads of up to 50 kW/m 2 which due to the predominantly short wavelength nature of the radiation emitted by the plasma will be absorbed within the first millimeter of any window. We will report on the detailed Finite Element (ANSYS R ) calculations of the heat and stress distribution across the windows. Calculations have been undertaken for a large number of different window materials which are required for the various spectral regions covered by the miscellaneous diagnostics, so that the most suitable material for each application can easily be identified. Also the dependence of the cooling rate on the window diameter and thickness has been studied. The calculations show that at a power load of 50 kW/m 2 cooled sapphire windows can be used for window sizes up to ∼200 mm diameter but that for many of the other materials like ZnSe, ZnS, CaF 2 , MgF 2 and quartz window sizes need to be limited to considerably smaller sizes. Detailed simulations of the local radiation power load distribution demonstrate that by careful design the load on individual optical components can be considerably reduced. A vacuum test chamber, equipped with a vacuum compatible IR heater has been build. In this chamber a low cost, easily exchangeable window design using Helicoflex gaskets on either side of a 60 mm exposed diameter quartz window have been successfully tested over 70 heat cycles up to a maximum temperature of 450 o C at power loads of 15 kW/m 2 . The design proved to be water and

  4. The integral analysis of 40 mm diameter pipe rupture in cooling system of fusion facility W7-X with ASTEC code

    Energy Technology Data Exchange (ETDEWEB)

    Kačegavičius, Tomas, E-mail: Tomas.Kacegavicius@lei.lt; Povilaitis, Mantas, E-mail: Mantas.Povilaitis@lei.lt

    2015-12-15

    Highlights: • The analysis of loss-of-coolant accident (LOCA) in W7-X facility. • Burst disc is sufficient to prevent pressure inside the plasma vessel exceeding 110 kPa. • Developed model of the cooling system adequately represents the expected phenomena. - Abstract: Fusion is the energy production technology, which could potentially solve problems with growing energy demand of population in the future. Wendelstein 7-X (W7-X) is an experimental facility of stellarator type, which is currently being built at the Max-Planck-Institute for Plasmaphysics located in Greifswald, Germany. W7-X shall demonstrate that in future the energy could be produced in such type of fusion reactors. The safety analysis is required before the operation of the facility could be started. A rupture of 40 mm diameter pipe, which is connected to the divertor unit (module for plasma cooling) to ensure heat removal from the vacuum vessel in case of no-plasma operation mode “baking” is one of the design basis accidents to be investigated. During “baking” mode the vacuum vessel structures and working fluid – water are heated to the temperature 160 °C. This accident was selected for the detailed analysis using integral code ASTEC, which is developed by IRSN (France) and GRS mbH (Germany). This paper presents the integral analysis of W7-X response to a selected accident scenario. The model of the main cooling circuit and “baking” circuit was developed for ASTEC code. There were analysed two cases: (1) rupture of a pipe connected to the upper divertor unit and (2) rupture of a pipe connected to the lower divertor unit. The results of analysis showed that in both cases the water is almost completely released from the units into the plasma vessel. In both cases the pressure in the plasma vessel rapidly increases and in 28 s the set point for burst disc opening is reached preventing further pressurisation.

  5. An optimization of robust SMES with specified structure H∞ controller for power system stabilization considering superconducting magnetic coil size

    International Nuclear Information System (INIS)

    Ngamroo, Issarachai

    2011-01-01

    Even the superconducting magnetic energy storage (SMES) is the smart stabilizing device in electric power systems, the installation cost of SMES is very high. Especially, the superconducting magnetic coil size which is the critical part of SMES, must be well designed. On the contrary, various system operating conditions result in system uncertainties. The power controller of SMES designed without taking such uncertainties into account, may fail to stabilize the system. By considering both coil size and system uncertainties, this paper copes with the optimization of robust SMES controller. No need of exact mathematic equations, the normalized coprime factorization is applied to model system uncertainties. Based on the normalized integral square error index of inter-area rotor angle difference and specified structured H ∞ loop shaping optimization, the robust SMES controller with the smallest coil size, can be achieved by the genetic algorithm. The robustness of the proposed SMES with the smallest coil size can be confirmed by simulation study.

  6. About the Toroidal Magnetic Field of a Tokamak Burning Plasma Experiment with Superconducting Coils

    International Nuclear Information System (INIS)

    Mazzucato, E.

    2002-01-01

    In tokamaks, the strong dependence on the toroidal magnetic field of both plasma pressure and energy confinement is what makes possible the construction of small and relatively inexpensive burning plasma experiments using high-field resistive coils. On the other hand, the toroidal magnetic field of tokamaks using superconducting coils is limited by the critical field of superconductivity. In this article, we examine the relative merit of raising the magnetic field of a tokamak plasma by increasing its aspect ratio at a constant value of the peak field in the toroidal magnet. Taking ITER-FEAT as an example, we find that it is possible to reach thermonuclear ignition using an aspect ratio of approximately 4.5 and a toroidal magnetic field of 7.3 T. Under these conditions, fusion power density and neutron wall loading are the same as in ITER [International Thermonuclear Experimental Reactor], but the normalized plasma beta is substantially smaller. Furthermore, such a tokamak would be able to reach an energy gain of approximately 15 even with the deterioration in plasma confinement that is known to occur near the density limit where ITER is forced to operate

  7. A quantitative investigation of the effect of a close-fitting superconducting shield on the coil factor of a solenoid

    DEFF Research Database (Denmark)

    Aarøe, Morten; Monaco, R.; Koshelet, V.

    2009-01-01

    Superconducting shields are commonly used to suppress external magnetic interference. We show, that an error of almost an order of magnitude can occur in the coil factor in realistic configurations of the solenoid and the shield. The reason is that the coil factor is determined by not only...... the geometry of the solenoid, but also the nearby magnetic environment. This has important consequences for many cryogenic experiments involving magnetic fields such as the determination of the parameters of Josephson junctions, as well as other superconducting devices. It is proposed to solve the problem...

  8. Analysis of magnetic energy stored in superconducting coils with and without ferromagnetic inserts

    International Nuclear Information System (INIS)

    Cha, Y.S.

    1993-01-01

    Inductance and energy of superconducting coils are calculated by (1) a long-solenoid approximation, (2) a finite-element model, and (3) working formulas and tables. The results of the finite-element model compare favorably with those of the working formulas. The long-solenoid approximation overpredicts the energy and inductance compared to the other two methods. The difference decreases with increasing length-to-diameter ratio. Energy stored in a coil with a ferromagnetic insert is calculated by using a long-solenoid approximation and a finite-element model. The analysis shows that the gain in energy ratio is equal to the relative permeability of the insert (which decreases with increasing current or current density). Even though large gains can be achieved at relatively low currents, the energy level itself is too low. The stored energy increases with current, but the gain decreases with increasing current because relative permeability decreases. If a coil with a diameter of 0.3 m and a length of 0.3 m is required to store 10 kJ of energy, the current density must equal 4000 A/cm 2 . The gain in energy ratio is equal to 2.55 when the insert is used

  9. Large superconducting detector magnets with ultra thin coils for use in high energy accelerators and storage rings

    International Nuclear Information System (INIS)

    Green, M.A.

    1977-08-01

    The development of a new class of large superconducting solenoid magnets is described. High energy physics on colliding beam machines sometimes require the use of thin coil solenoid magnets. The development of these magnets has proceeded with the substitution of light materials for heavy materials and by increasing the current density in the coils. The Lawrence Berkeley Laboratory has developed a radical approach to the problem by having the coil operate at very high current densities. This approach and its implications are described in detail

  10. Introduction of fuzzy logic theorem for quench detection in the superconducting coil system of a Large Helical Device

    International Nuclear Information System (INIS)

    Adachi, Yamato; Ninomiya, Akira; Uriu, Yoshihisa; Ishigohka, Takeshi; Mito, Toshiyuki; Imagawa, Shinsaku; Yanagi, Nagato; Sekiguchi, Haruo; Yamada, Shuichi

    2005-01-01

    We have analyzed the state of the superconducting coil system in a LHD at NIFS (National Institute of Fusion Science) using a fuzzy logic theorem to detect quenching at an early stage. In this method, the 'warning coefficient' of the coil system is calculated. As for the fuzzy variables, 'effective stored heat' in the coil is introduced in addition to the voltage signal in order to improve quench detection and state estimation. The 'effective stored heat' is an integrated value of the heat generated in the coil on the assumption that instantaneous heat in the conductor is continuously cooled by liquid helium. Experiments conducted using the LHD coils confirmed that quench alarm signals can be issued with sufficient lead time before quenching. On the other hand, in the case of small local disturbances, the system shows only a small increase in the caution level. (author)

  11. Application of AE technique for on-line monitoring of quenching in racetrack superconducting coil at cryogenic environment

    International Nuclear Information System (INIS)

    Lee, Jun Hyun; Lee, Min Rae; Shon, Myung Hwan; Kwon, Young Kil

    1998-01-01

    An acoustic emission(AE) technique has been used to monitor and diagnose quenching phenomenon in racetrack shaped superconducting magnets at cryogenic environment of 4.2 K. The ultimate goal is to ensure the safety and reliability of large superconducting magnet systems by being able to identity and locate the sources of quench in superconducting magnets. The characteristics of AE parameters have been analyzed by correlating with quench number, winding tension of superconducting coil and charge rate by transport current. It was found in this study that there was good correlation between quench current and AE parameters. The source location of quenching in superconducting magnet was also discussed on the hashing of correlation between magnet voltage and AE energy.

  12. Analysis of a dc commutator machine for exchange of energy with a superconducting coil

    International Nuclear Information System (INIS)

    Vogel, H.F.

    1978-08-01

    A 500-kW dc commutator machine, C, is analyzed for use in an LC circuit with a ringing period of approximately 4 s with a superconducting coil, L. Electrical measurements and the important design equations and characteristics are listed. Attention is paid to the calculation of the commutating voltage, which is an important design feature because it sets a limit to the current allowable in the LC circuit, amounting to 6 times rated machine current. The equations for the energy loss components of the generator are given and fitted to experimental coast-down data. With a fitting accuracy of 1.2%, the loss coefficients for the bearing loss, brush loss, windage loss, and tooth eddy current loss in the remanent stator field are thus determined

  13. Orsay cyclotron design with superconducting coils and the associated accelerating unit

    International Nuclear Information System (INIS)

    1983-06-01

    This report ends the theoretical and technical studies of the project of new accelerating unit proposed by IPN at Orsay. The isochronous cyclotron with superconducting coils is coupled to two different injections: an axial one with polarized or not ion sources for light ions or multicharged ion sources for heavy ions; a radial injection from the reviewed tandem MP13Met. The following points are underlined: 1) the specificity of the machine 2) the theoretical and technical feasibility of a compact high frequency accelerating system suited to this type of machine 3) the development of an extraction device of the beam 4) the feasibility of an axial injection along the optical axis coupled to a unique central region of the cyclotron 5) the criterions to define, the choices to make to get a radial injection of the beam coming from the tandem in the cyclotron [fr

  14. Cryogenic magnetic coil and superconducting magnetic shield for neutron electric dipole moment searches

    Science.gov (United States)

    Slutsky, S.; Swank, C. M.; Biswas, A.; Carr, R.; Escribano, J.; Filippone, B. W.; Griffith, W. C.; Mendenhall, M.; Nouri, N.; Osthelder, C.; Pérez Galván, A.; Picker, R.; Plaster, B.

    2017-08-01

    A magnetic coil operated at cryogenic temperatures is used to produce spatial, relative field gradients below 6 ppm/cm, stable for several hours. The apparatus is a prototype of the magnetic components for a neutron electric dipole moment (nEDM) search, which will take place at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory using ultra-cold neutrons (UCN). That search requires a uniform magnetic field to mitigate systematic effects and obtain long polarization lifetimes for neutron spin precession measurements. This paper details upgrades to a previously described apparatus [1], particularly the introduction of super-conducting magnetic shielding and the associated cryogenic apparatus. The magnetic gradients observed are sufficiently low for the nEDM search at SNS.

  15. Design of a 28 MW pulse facility for testing superconducting coils to several hundred megajoules capacity

    International Nuclear Information System (INIS)

    Vogel, H.F.

    1980-01-01

    Railway traction motors are available in unit sizes convenient for installation and series-parallel grouping. They are rugged. Industry builds and refurbishes them with good economy and in quantities replenishing the rolling stock. We find them well suited for reversing the current in a superconducting winding. We focus on a pulsed energy of 20 to 100 MJ, discussing our analysis and facility planning. Limitations are imposed by the following maximum numbers tolerated by the motor - pulsed current of 3.0 to 3.5 kA, current change of 40 kA/s, and pulsed voltage of 1.8 kV. Hence, the number of machines needed in parallel follows from the coil current and its rate of change. The number in series is determined by the voltage. The power transfer is limited by the torsional strength of the motor shaft to a value affected by the flywheel mass

  16. Higher magnetic field multipoles generated by superconductor magnetization within a set of nested superconducting correction coils

    International Nuclear Information System (INIS)

    Green, M.A.

    1990-01-01

    Correction elements in colliding beam accelerators such as the Superconducting Super Collider (SSC) can be the source of undesirable higher magnetic field multipoles due to magnetization of the superconductor within the corrector. Quadrupole and sextupole correctors located within the main dipole will produce sextupole and decapole due to magnetization of the superconductor within the correction coils. Lumped nested correction coils can produce a large number of skew and normal magnetization multipoles which may have an adverse effect on a stored beam at injection into a high energy colliding beam machine such as the SSC. Multipole magnetization field components have been measured within the HERA storage ring dipole magnets. Calculations of these components using the SCMAG04 code, which agree substantially with the measured multipoles, are presented in the report. As a result, in the proposed continuous correction winding for the SSC, dipoles have been replaced with lumped correction elements every six dipole magnets (about 120 meters apart). Nested lumped correction elements will also produce undesirable higher magnetization multipoles. This report shows a method by which the higher multipole generated by nested correction elements can be identified. (author)

  17. Improvements in or relating to superconductive magnet coils and their formers

    International Nuclear Information System (INIS)

    McDougall, I.L.

    1977-01-01

    A method of manufacturing a superconductive magnet coil is described comprising winding on to a former a wire containing the components of a superconductive intermetallic compound and heating the assembly to a temperature such that the components of the compound react to form the intermetallic compound. The former should be made of metal, such as steel or stainless steel, of melting point higher than that at which the reaction occurs, and should have on all portions of its surface contacted by the wire a coating of a refractory material, such as Al 2 O 3 , non reactive with the metal and the wire. The wire may contain, after reaction, filaments of the intermetallic compound, and adjacent strands of wire in a single layer may be insulated one from the other by refractory material. A flange is formed on one end of the former, which may be cylindrical in shape. The refractory coating of the former may be flame sprayed into the metal. (U.K.)

  18. Three-dimensional Monte Carlo simulations of W7-X plasma transport: density control and particle balance in steady-state operations

    International Nuclear Information System (INIS)

    Sharma, D.; Feng, Y.; Sardei, F.; Reiter, D.

    2005-01-01

    This paper presents self-consistent three-dimensional (3D) plasma transport simulations in the boundary of stellarator W7-X obtained with the Monte Carlo code EMC3-EIRENE for three typical island divertor configurations. The chosen 3D grid consists of relatively simple nested finite toroidal surfaces defined on a toroidal field period and covering the whole edge topology, which includes closed surfaces, islands and ergodic regions. Local grid refinements account for the required high resolution in the divertor region. The distribution of plasma density and temperature in the divertor region, as well as the power deposition profiles on the divertor plates, are shown to strongly depend on the island geometry, i.e. on the position and size of the dominant island chain. Configurations with strike-point positions closer to the gap of the divertor chamber generally favour the neutral compression in the divertor chamber and hence the pumping efficiency. The ratio of pumping to recycling fluxes is found to be roughly independent of the separatrix density and is thus a figure of merit for the quality of the configuration and of the divertor system in terms of density control. Lower limits for the achievable separatrix density, which determine the particle exhaust capabilities in stationary conditions, are compared for the three W7-X configurations

  19. Residual gas analysis of a cryostat vacuum chamber during the cool down of SST - 1 superconducting magnet field coil

    International Nuclear Information System (INIS)

    Semwal, P.; Joshi, K.S.; Thankey, P.L.; Pathan, F.S.; Raval, D.C.; Patel, R.J.; Pathak, H.A.

    2005-01-01

    One of the most important feature of Steady state Superconducting Tokamak -1 (SST-l) is the Nb-Ti superconducting magnet field coils. The coils will be kept in a high vacuum chamber (Cryostat) and liquid Helium will be flown through it to cool it down to its critical temperature of 4.5K. The coil along with its hydraulics has four types of joints (1) Stainless Steel (S.S.) to Copper (Cu) weld joints (2) S. S. to S. S. weld joints (3) Cu to Cu brazed joints and (4) G-10 to S. S. joints with Sti-cast as the binding material. The joints were leak tested with a Helium mass spectrometer leak detector in vacuum as well as in sniffer mode. However during the cool-down of the coil, these joints may develop leaks. This would deteriorate the vacuum inside the cryostat and coil cool-down would subsequently become more difficult. To study the effect of cooling on the vacuum condition of the Cryostat, a dummy Cryostat chamber was fabricated and a toroidal Field (TF) magnet was kept inside this chamber and cooled down to 4.5 K.A residual gas analyzer (RGA) was connected to the Cryostat chamber to study the behaviour of major gases inside this chamber with temperature. An analysis of the RGA data acquired during the coo-down has been presented in this chamber. (author)

  20. Superconductivity and fusion energy—the inseparable companions

    Science.gov (United States)

    Bruzzone, Pierluigi

    2015-02-01

    Although superconductivity will never produce energy by itself, it plays an important role in energy-related applications both because of its saving potential (e.g., power transmission lines and generators), and its role as an enabling technology (e.g., for nuclear fusion energy). The superconducting magnet’s need for plasma confinement has been recognized since the early development of fusion devices. As long as the research and development of plasma burning was carried out on pulsed devices, the technology of superconducting fusion magnets was aimed at demonstrations of feasibility. In the latest generation of plasma devices, which are larger and have longer confinement times, the superconducting coils are a key enabling technology. The cost of a superconducting magnet system is a major portion of the overall cost of a fusion plant and deserves significant attention in the long-term planning of electricity supply; only cheap superconducting magnets will help fusion get to the energy market. In this paper, the technology challenges and design approaches for fusion magnets are briefly reviewed for past, present, and future projects, from the early superconducting tokamaks in the 1970s, to the current ITER (International Thermonuclear Experimental Reactor) and W7-X projects and future DEMO (Demonstration Reactor) projects. The associated cryogenic technology is also reviewed: 4.2 K helium baths, superfluid baths, forced-flow supercritical helium, and helium-free designs. Open issues and risk mitigation are discussed in terms of reliability, technology, and cost.

  1. Circuit design and simulation of a HV-supply controlling the power of 140 GHz 1 MW gyrotrons for ECRH on W7-X

    International Nuclear Information System (INIS)

    Brand, P.; Mueller, G.A.

    2003-01-01

    For plasma heating by ECR in the Stellarator W7-X under construction, 140 GHz gyrotrons with 1 MW cw output power are under development. These tubes have a voltage depressed collector for electron energy recovery. Each gyrotron is fed by two high-voltage sources: a high-power supply for driving the electron beam and a precision low-power supply for beam acceleration. In addition, a protection system with a thyratron crowbar for fast power removal in case of gyrotron arcing is installed. The low-power high-voltage source for beam acceleration is realized by a high-voltage servo-amplifier driving the depression voltage such that the influence of the voltage noise of the main high-power supply on the acceleration voltage is suppressed by feed-back control of the amplifier. Design and simulation of the servo-amplifier by PSpice is presented

  2. In vivo MR imaging of the human skin at subnanoliter resolution using a superconducting surface coil at 1.5 Tesla.

    Science.gov (United States)

    Laistler, Elmar; Poirier-Quinot, Marie; Lambert, Simon A; Dubuisson, Rose-Marie; Girard, Olivier M; Moser, Ewald; Darrasse, Luc; Ginefri, Jean-Christophe

    2015-02-01

    To demonstrate the feasibility of a highly sensitive superconducting surface coil for microscopic MRI of the human skin in vivo in a clinical 1.5 Tesla (T) scanner. A 12.4-mm high-temperature superconducting coil was used at 1.5T for phantom and in vivo skin imaging. Images were inspected to identify fine anatomical skin structures. Signal-to-noise ratio (SNR) improvement by the high-temperature superconducting (HTS) coil, as compared to a commercial MR microscopy coil was quantified from phantom imaging; the gain over a geometrically identical coil made from copper (cooled or not) was theoretically deduced. Noise sources were identified to evaluate the potential of HTS coils for future studies. In vivo skin images with isotropic 80 μm resolution were demonstrated revealing fine anatomical structures. The HTS coil improved SNR by a factor 32 over the reference coil in a nonloading phantom. For calf imaging, SNR gains of 380% and 30% can be expected over an identical copper coil at room temperature and 77 K, respectively. The high sensitivity of HTS coils allows for microscopic imaging of the skin at 1.5T and could serve as a tool for dermatology in a clinical setting. © 2013 Wiley Periodicals, Inc.

  3. Design of superconducting toroidal magnet coils and testing facility in the USA

    International Nuclear Information System (INIS)

    Luton, J.N.; Haubenreich, P.N.; Thompson, P.B.

    1977-01-01

    In the U.S. Large Coil Program, three industrial teams are presently designing test coils to general specifications prepared by the Oak Ridge National Laboratory with guidance from USERDA. Each test coil is approximately half the bore size of reactor coils, being oval or D-shaped, with a bore of 2.5 x 3.5 m. The dimensions and operating requirements of the coils are identical for all test coils. The coils are designed to produce a peak field of at least 8 tesla at the winding of a selected coil operated at its design current. This condition is met when the selected coil is operated in a compact toroidal array of 6 coils, with the other five coils being operated at 0.8 of their design current. The six coils are of three different designs. Both pool boiling and forced flow designs are included. The coils are housed in a single large vacuum chamber for economy and testing convenience. Auxiliary coils provide a pulse field over the test coil winding volume. This auxiliary system is designed to produce a pulse field which rises to a peak of 0.14 T in 1 sec. With the exception of material damage due to neutron irradiation, all reactor requirements and environments will be either duplicated, approximated, or simulated. The test facility is being designed to accept coils producing up to 12 tesla in later phases of the program

  4. Persistent current analysis of superconducting coils in a linear synchronous motor for maglev passenger transport system. Fujoshiki tetsudoyo linear doki motor ni okeru teijisoku mode chodendo coil denryu no kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Azusawa, T [Toshiba Corp., Tokyo (Japan)

    1994-05-20

    The simple analysis method of persistent current induced in on-board superconducting coils was proposed for the vehicle of a superconducting magnetically-suspended train which is running in the magnetic field generated by armature coil current of a linear synchronous motor installed along a guideway, and the performance of the method is discussed through calculation based on typical models. As fluctuation of persistent current due to running was calculated with various parameter values under a normal running condition, fluctuation of persistent current induced was less then 1% of an initial magnetomotive force, having no adverse effect on the stability and reliability of superconducting magnets. Electromagnetic forces under a normal running condition could be predicted accurately enough by relatively easy-to-calculate constant current mode analysis. Double-layered armature coils were preferred to single-layered ones to enhance the stability of superconducting magnets by reducing fluctuation of persistent current. 10 refs., 8 figs., 1 tab.

  5. Magnetic study of extraction elements of compact cyclotron beam with AGOR superconducting coils

    International Nuclear Information System (INIS)

    Gustafsson, S.

    1991-12-01

    The extraction system of the superconducting cyclotrons is normally making a large use of electric extractors followed by magnetostatic elements. The electric field limit initially hoped for (14 MV/m) has been shown to be too optimistic. A more realistic value is around 10 MV/m in the concerned geometries. The first element of the AGOR extraction system is an electrostatic channel where the maximum electric field is limited to 10.5 MV/m. The smaller separation between the internal beam and the extracted beam at the entrance of the first magnetic element is compensated by the replacement of the usual magnetostatic channels with high power electromagnetic channels placed in the reduced space close to the internal beam and where the horizontal position can be adjusted according to the kind of ion accelerated and its energy. The fringing field very close to the channels is controlled with the help of correction coils reducing the perturbations of the internal beam trajectories to an acceptable level

  6. Study of superconducting magnetic bearing applicable to the flywheel energy storage system that consist of HTS-bulks and superconducting-coils

    International Nuclear Information System (INIS)

    Seino, Hiroshi; Nagashima, Ken; Tanaka, Yoshichika; Nakauchi, Masahiko

    2010-01-01

    The Railway Technical Research Institute conducted a study to develop a superconducting magnetic bearing applicable to the flywheel energy-storage system for railways. In the first step of the study, the thrust rolling bearing was selected for application, and adopted liquid-nitrogen-cooled HTS-bulk as a rotor, and adopted superconducting coil as a stator for the superconducting magnetic bearing. Load capacity of superconducting magnetic bearing was verified up to 10 kN in the static load test. After that, rotation test of that approximately 5 kN thrust load added was performed with maximum rotation of 3000rpm. In the results of bearing rotation test, it was confirmed that position in levitation is able to maintain with stability during the rotation. Heat transfer properties by radiation in vacuum and conductivity by tenuous gas were basically studied by experiment by the reason of confirmation of rotor cooling method. The experimental result demonstrates that the optimal gas pressure is able to obtain without generating windage drag. In the second stage of the development, thrust load capacity of the bearing will be improved aiming at the achievement of the energy capacity of a practical scale. In the static load test of the new superconducting magnetic bearing, stable 20kN-levitation force was obtained.

  7. Effect of capacitive feedback on the characteristics of direct current superconducting quantum interference device coupled to a multiturn input coil

    International Nuclear Information System (INIS)

    Minotani, T.; Enpuku, K.; Kuroki, Y.

    1997-01-01

    Distortion of voltage versus flux (V endash Φ) relation of a dc superconducting quantum interference device (SQUID) coupled to a multiturn input coil is studied. First, resonant behavior of the coupled SQUID due to the so-called input coil resonance is clarified. It is shown that large rf noise flux is produced by the input coil resonance. This rf flux is added to the SQUID, and results in large rf voltage across the SQUID. In the case where parasitic capacitance exists between the input coil and the ground of the SQUID, this rf voltage produces the rf flux again, i.e., a feedback loop for the rf flux is formed. Taking into account this capacitive feedback, we study the V endash Φ relation of the coupled SQUID. Numerical simulation shows that the V endash Φ relation is distorted considerably by the feedback mechanism. The simulation result explains well the experimental V endash Φ relation of the coupled SQUID. The combination of the input coil resonance with the capacitive feedback is the most likely mechanism for the distorted V endash Φ curve of the coupled SQUID. The condition for occurrence of the distorted V endash Φ curve due to the capacitive feedback is also obtained, and methods to prevent degradation are discussed. copyright 1997 American Institute of Physics

  8. Pure tension superconducting toroidal-field coil system design studies for the Argonne Experimental Power Reactor

    International Nuclear Information System (INIS)

    Wang, S.T.; Purcell, J.R.; Demichele, D.W.; Turner, L.R.

    1975-11-01

    As part of the Argonne Tokamak Experimental Power Reactor (TEPR) design studies, a toroidal field (TF) coil system has been designed. NbTi was chosen as the most suitable superconductor and 8T was regarded as a practical peak field level in this study. The 16-coil design was chosen as a reasonable compromise between 2 percent field ripple and 3 m access gap. To minimize the coil structure and the bending moments on the conductor, a pure tension coil shape is necessary. A correct approach for determining the pure tension coil profile in a bumpy TF coil system is given. Verification of the pure tension coil by a three-dimensional stress analysis is presented. For coil quench protection, a series-connected scheme is proposed

  9. Study on the optimum design of a high temperature superconducting coil

    International Nuclear Information System (INIS)

    Ishiguri, Shinichi; Yamaguchi, Mitsugi; Fukui, Satoshi; Ogawa, Jun; Sato, Takao

    2005-01-01

    It is in particular of importance for HTS coils to secure a larger central magnetic field, a large stored energy, etc. with shorter length of HTS tapes. The critical current of an HTS tape depends on both the flux density and the flux angle with respect to tapes. In view of this, the performance improvement of HTS coils is taken into account with an analytical model. As a coil shape, the minimum volume coil derived from the Fabry Factor constant curve is taken up, which is often employed at low temperature coils. The electric field distribution within a coil cross-section is calculated to examine effects on a current carrying capability. It is clear that high electric field portions appear at the coil edge region due primarily to inclined magnetic fluxes against HTS tapes. Considering this, a grade winding method of a coil is proposed, where the winding density of conductors is reduced at coil edge portions. With this coil winding structure, the critical current of an HTS coil is improved since the magnetic field is reduced at edge portions. The stored energy per HTS tape length and the central magnetic field of the coil can be remarkably increased by this kind of grade winding method

  10. Effect of epoxy impregnation on strain distribution of materials in Bi2223 superconducting coils by using synchrotron X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Xinzhe, E-mail: xinzhe.jin@riken.jp [Center for Life Science Technologies, RIKEN, Yokohama-shi, Kanagawa 230-0045 (Japan); Osamura, Kozo [Research Institute for Applied Sciences, Sakyo-ku, Kyoto 606-8202 (Japan); Machiya, Shutaro [Daido University, Minami-ku, Nagoya 457-8530 (Japan); Kajiwara, Kentaro [Japan Synchrotron Radiation Research Institute, Sayo, Hyogo 679-5198 (Japan); Shobu, Takahisa [Japan Atomic Energy Agency, Sayo, Hyogo 679-5148 (Japan); Maeda, Hideaki [Center for Life Science Technologies, RIKEN, Yokohama-shi, Kanagawa 230-0045 (Japan)

    2015-11-25

    Synchrotron X-rays have been used to observe strain distributions in composite materials such as superconducting wires with a thickness of less than about 2 mm. In applications that employ wound coils of superconducting wire, it is necessary to understand the strain distribution within the coiled wire. Superconducting wires such as Bi2223 and REBCO wires approximately 4–5 mm wide are commercially available. Coiled wires of this width are too thick to easily measure using conventional X-ray techniques, especially the inner strain, because the penetration depth tends to be around 2 mm. Therefore, the beam penetration must be improved, and it is known that the penetration depth of an X-ray beam depends upon the beam energy, beam intensity, measurement material, and measurement method. In this study, we used a white X-ray diffractometer at SPring-8 to develop a method of observing the strain distribution in Bi2223 superconducting coils winded by a 4.5 mm wide Bi2223 wire. We successfully observed a clear (400) peak of the Bi2223 phase by an appropriate measurement condition, and then observed the strains of each material in the Bi2223 coils with and without epoxy impregnation. This is the first time that we have obtained the strain of a Bi2223 phase in coiled wire using synchrotron X-ray diffraction. Further synchrotron-based study of superconducting coils will be useful in the development of advanced high-field magnets. The appropriate measurement method and the obtained measurement results are presented in this paper. - Highlights: • We successfully obtained clear peaks of Bi2223 phase in 4.5 mm thick coils. • The strain behaviors of materials in the coil correspond to a three turn cycle model. • A uniform strain distribution of the Bi2223 phase was obtained by epoxy impregnation.

  11. Conceptual design report for a superconducting coil suitable for use in the large solenoid detector at the SSC [Superconducting Super Collider

    International Nuclear Information System (INIS)

    Fast, R.W.; Grimson, J.H.; Krebs, H.J.; Kephart, R.D.; Theriot, D.; Wands, R.H.

    1989-01-01

    The conceptual design of a large superconducting solenoid suitable for a magnetic detector at the Superconducting Super Collider (SSC) was done at Fermilab. The magnet will provide a magnetic field of 1.7 T over a volume 8 m in diameter by 16 m long. The particle-physics calorimetry will be inside the field volume and so the coil will be bath cooled and cryostable; the vessels will be stainless steel. Predictability of performance and the ability to safely negotiate all probable failure modes, including a quench, are important items of the design philosophy. Our conceptual design of the magnet and calorimeter has convinced us that this magnet is a reasonable extrapolation of present technology and is therefore feasible. The principal difficulties anticipated are those associated with the very large physical dimensions and stored energy of the magnet. 5 figs

  12. Observations of the effects of magnetic topology on the SOL characteristics of an electromagnetic coherent mode in the first experimental campaign of W7-X

    Science.gov (United States)

    Liu, S. C.; Liang, Y.; Drews, P.; Krämer-Flecken, A.; Han, X.; Nicolai, D.; Satheeswaran, G.; Wang, N. C.; Cai, J. Q.; Charl, A.; Cosfeld, J.; Fuchert, G.; Gao, Y.; Geiger, J.; Grulke, O.; Henkel, M.; Hirsch, M.; Hoefel, U.; Hollfeld, K. P.; Höschen, D.; Killer, C.; Knieps, A.; König, R.; Neubauer, O.; Pasch, E.; Rahbarnia, K.; Rack, M.; Sandri, N.; Sereda, S.; Schweer, B.; Wang, E. H.; Wei, Y. L.; Weir, G.; Windisch, T.; W7-X Team

    2018-04-01

    Turbulence is considered to play an important role in the edge cross field heat and particle transport in fusion devices. Scrape-off layer (SOL) turbulence characteristics were measured by the combined probe mounted on the multi-purpose manipulator during the first experimental campaign of W7-X. An electromagnetic coherent mode (EMCM) at 7 kHz has been observed by multiple diagnostics in both the plasma core and the SOL and exhibits a strong dependence of the magnetic topology. As demonstrated by the measurements of the combined probe, the EMCM starts to appear at a radius of R  =  6.15 m along the path of probe measurement and this location is shifted inwards in higher iota configurations. It propagates along the direction of electron diamagnetic drift in the far SOL with a poloidal velocity about 0.6 km s-1 while it turns to the opposite direction gradually in the near SOL in the laboratory frame, but keeps a velocity of about 0.6-0.7 km s-1 along the direction of electron diamagnetic drift in the plasma frame. This mode can be induced by raising the ECRH heating power in similar discharge conditions, which is probably linked to the gradient of electron temperature and pressure. The EMCM is enhanced significantly in the edge magnetic island with long connection length where the EMCM can grow up due to the long particle confinement time.

  13. Spiral MRI on a 9.4T Vertical-bore Superconducting Magnet Using Unshielded and Self-shielded Gradient Coils

    Science.gov (United States)

    Kodama, Nao; Setoi, Ayana; Kose, Katsumi

    2018-01-01

    Spiral MRI sequences were developed for a 9.4T vertical standard bore (54 mm) superconducting magnet using unshielded and self-shielded gradient coils. Clear spiral images with 64-shot scan were obtained with the self-shielded gradient coil, but severe shading artifacts were observed for the spiral-scan images acquired with the unshielded gradient coil. This shading artifact was successfully corrected with a phase-correction technique using reference scans that we developed based on eddy current field measurements. We therefore concluded that spiral imaging sequences can be installed even for unshielded gradient coils if phase corrections are performed using the reference scans. PMID:28367906

  14. Spiral MRI on a 9.4T Vertical-bore Superconducting Magnet Using Unshielded and Self-shielded Gradient Coils.

    Science.gov (United States)

    Kodama, Nao; Setoi, Ayana; Kose, Katsumi

    2018-04-10

    Spiral MRI sequences were developed for a 9.4T vertical standard bore (54 mm) superconducting magnet using unshielded and self-shielded gradient coils. Clear spiral images with 64-shot scan were obtained with the self-shielded gradient coil, but severe shading artifacts were observed for the spiral-scan images acquired with the unshielded gradient coil. This shading artifact was successfully corrected with a phase-correction technique using reference scans that we developed based on eddy current field measurements. We therefore concluded that spiral imaging sequences can be installed even for unshielded gradient coils if phase corrections are performed using the reference scans.

  15. Design and manufacturing status of trim coils for the Wendelstein 7-X stellarator experiment

    Energy Technology Data Exchange (ETDEWEB)

    Riße, K., E-mail: konrad.risse@ipp.mpg.de [Max-Planck-Institut für Plasmaphysik, Greifswald (Germany); Rummel, Th.; Freundt, S.; Dudek, A.; Renard, S.; Bykov, V.; Köppen, M. [Max-Planck-Institut für Plasmaphysik, Greifswald (Germany); Langish, S.; Neilson, G.H.; Brown, Th.; Chrzanowski, J.; Mardenfeld, M.; Malinowski, F.; Khodak, A.; Zhao, X. [Princeton Plasma Physics Laboratory, Princeton, NJ (United States); Eksaa, G. [Everson Tesla Inc., Nazareth, PA (United States)

    2013-10-15

    Highlights: ► The trim coil system will fine tune the main magnetic field during plasma operation by reducing the magnetic field errors. ► The coil design and operational parameters are fixed, the manufacturing is running. ► The coils are equipped with temperature sensors and a voltage tap system to monitor the coil temperature. ► The max. operational deflection is in the order of 4.5 mm; the max. shearing stress across bond planes is of order 16 MPa. ► Special clamps equipped with elastomeric pads allow fixing the coils on the outer cryostat wall. -- Abstract: The stellarator fusion experiment Wendelstein 7-X (W7-X) is currently under construction at the Max-Planck-Institut für Plasmaphysik in Greifswald, Germany. The main magnetic field will be provided by a superconducting magnet system which generates a fivefold toroidal periodic magnetic field. However, unavoidable tolerances can result in small deviations of the magnetic field which disturb the toroidal periodicity. In order to have a tool to influence these field errors five additional normal conducting trim coils were designed to allow fine tuning of the main magnetic field during plasma operation. In the frame of an international cooperation the trim coils will be contributed by the US partners. Princeton Plasma Physics Laboratory has accomplished several tasks to develop the final design ready for manufacturing e.g. detailed manufacturing design for the winding and for the coil connection area. The design work was accompanied by a detailed analysis of resulting forces and moments to prove the design. The manufacturing of the coils is running at Everson Tesla Inc; the first two coils were received at IPP.

  16. Superconducting toroidal field coil power supply and protection system for NET

    International Nuclear Information System (INIS)

    Hicks, J.B.

    1986-01-01

    A power supply and quench protection system is proposed in which alternate coils are connected in series to produce two separate circuits, each with 8 coils. Both circuits are provided with power supplies comprising rectifier transformers and thyristor equipped Graetz bridges, which are operated at maximum forward voltage (125 V) to charge the coils to 24 kA, 17.75 GJ in ≅ 2 hours and are fully inverted for scheduled discharges. Pulsed firing of the thyristors allows the same power supplies to be used to maintain the currents against resistive losses, without increasing the reactive power consumption or harmonic current generation. Rapid discharges are initiated by opening d.c. circuit breakers to introduce discharge resistors between the coils of each circuit. The maximum possible value of peak voltage-to-ground is then limited to 2.25 times the discharge voltage applied to each coil. A 5 kV discharge voltage allows the coils to be discharged with a time constant of 18.5 s, which is sufficiently rapid to limit the quench ''hot spot'' temperature to 68 K. The coil connections impose sufficient symmetry on the coil current distribution to ensure that no out-of-plane forces are produced on the coils. Even if one circuit breaker fails to interrupt, the variation of coil currents is sufficiently small that the resulting symmetric variation of radial centring forces is acceptable

  17. Echo-Planar Imaging for a 9.4 Tesla Vertical-Bore Superconducting Magnet Using an Unshielded Gradient Coil.

    Science.gov (United States)

    Kodama, Nao; Kose, Katsumi

    2016-10-11

    Echo-planar imaging (EPI) sequences were developed for a 9.4 Tesla vertical standard bore (~54 mm) superconducting magnet using an unshielded gradient coil optimized for live mice imaging and a data correction technique with reference scans. Because EPI requires fast switching of intense magnetic field gradients, eddy currents were induced in the surrounding metallic materials, e.g., the room temperature bore, and this produced serious artifacts on the EPI images. We solved the problem using an unshielded gradient coil set of proper size (outer diameter = 39 mm, inner diameter = 32 mm) with time control of the current rise and reference scans. The obtained EPI images of a phantom and a plant sample were almost artifact-free and demonstrated the promise of our approach.

  18. Localization of Electrical Insulation Failures in Superconducting Collared Coils by Analysis of the Distortion of a Pulsed Magnetic Field

    CERN Document Server

    Komorowski, P A

    2000-01-01

    The localization of possible electrical faults in superconducting accelerator magnets may, in most cases, be a complex, expensive and time-consuming process. In particular, inter-turn short circuits and failures of the ground insulation are well detectable when the magnet is collared, but often disappear after disassembly for repair due to the release of the pre-stress in the coils. The fault localization method presented in this paper is based on the measurement and analysis of the magnetic field generated inside the magnet aperture by a high voltage pulse. The presence of the fault modifies the distribution of the current in the coils and produces a distortion of the magnetic field. The described method aims at locating both the longitudinal and azimuthal position of the fault-affected area. The test method, the transient case FEM models and the implemented experimental set-up are presented and discussed for the LHC dipole models.

  19. Echo-Planar Imaging for a 9.4 Tesla Vertical-Bore Superconducting Magnet Using an Unshielded Gradient Coil

    Science.gov (United States)

    KODAMA, Nao; KOSE, Katsumi

    2016-01-01

    Echo-planar imaging (EPI) sequences were developed for a 9.4 Tesla vertical standard bore (∼54 mm) superconducting magnet using an unshielded gradient coil optimized for live mice imaging and a data correction technique with reference scans. Because EPI requires fast switching of intense magnetic field gradients, eddy currents were induced in the surrounding metallic materials, e.g., the room temperature bore, and this produced serious artifacts on the EPI images. We solved the problem using an unshielded gradient coil set of proper size (outer diameter = 39 mm, inner diameter = 32 mm) with time control of the current rise and reference scans. The obtained EPI images of a phantom and a plant sample were almost artifact-free and demonstrated the promise of our approach. PMID:27001398

  20. Numerical analyses of magnetic field and force in toroidal superconducting magnetic energy storage using unit coils (abstract)

    International Nuclear Information System (INIS)

    Kanamaru, Y.; Nakayama, T.; Amemiya, Y.

    1997-01-01

    Superconducting magnetic energy storage (SMES) is more useful than other systems of electric energy storage because of its larger amounts of stored energy and its higher efficiency. There are two types of SMES. One is the solenoid type and the other is the toroidal type. Some models of solenoid-type SMES are designed in the U.S. and in Japan. But the large scale SMES causes a high magnetic field in the living environment, and causes the erroneous operation of electronic equipment. The authors studied some suitable designs of magnetic shielding for the solenoidal-type SMES to reduce the magnetic field in the living environment. The toiroidal type SMES is studied in this article. The magnetic leakage flux of the toiroidal-type SMES is generally lower than that of the solenoid-type SMES. The toroidal-type SMES is constructed of unit coils, which are convenient for construction. The magnetic leakage flux occurs between unit coils. The electromagnetic force of the coils is very strong. Therefore analyses of the leakage flux and electromagnetic force are important to the design of SMES. The authors studied the number, radius, and length of unit coils. The storage energy is 5 G Wh. The numerical analyses of magnetic fields in the toroidal type SMES are obtained by analytical solutions. copyright 1997 American Institute of Physics

  1. Experimental and calculating study on the stressed state of superconducting coils of toroidal field in the T-15 tokamak

    International Nuclear Information System (INIS)

    Vaulina, I.G.; Gusev, S.V.; Sivkova, G.N.

    1987-01-01

    Results of calculational and experimental atudy of stress-deformed state of superconducting coils of the T-15 tokamak toroidal field are presented. The calculations are made using the method of finite elements and refined theory of cores. Experimental studies were carried out using elastic tensometric model of polymer materials. Test results are compared with the calculational results. Divergence between calculational and experimental values of displacement of characteristic points in the unit does not exceed 20 %. Results of model studies confirm the expediency of the calculational model used for designing SOTP unit for the T-15 tokamak

  2. Role of the large coil program in the development of superconducting magnets for fusion reactors

    International Nuclear Information System (INIS)

    Haubenreich, P.N.; Luton, J.N.; Thompson, P.B.

    1978-01-01

    Three U.S. industrial teams are designing and will build one coil each to a common set of specifications. Coil specifications and test conditions were chosen to insure maximum relevance to fusion program needs. Each test coil will have a 2.5 x 3.5 m D-shape bore, will contain about 7 MA-turns, and must operate at a peak field of 8 T while subjected to pulsed fields up to 0.14 T in a test stand that can accommodate up to 6 coils in a compact toroidal array. Coils by General Dynamics/Convair and General Electric will use different NbTi conductors cooled by pool-boiling helium. The Westinghouse coil will use Nb 3 Sn cooled by a forced flow of supercritical helium. These coils will be delivered in 1980 and 1981 for testing in the Large Coil Test Facility at Oak Ridge in a compact toroidal array with three coils from outside the U.S. These will be produced by EURATOM, Japan, and Switzerland for testing under an International Energy Agency agreement

  3. Results of measurements with a superconducting niobium coil resonator at 106 MHz: the story of a coil

    International Nuclear Information System (INIS)

    Piosczyk, B.

    A number of tests were performed with a newly developed coil. The surface was treated by conventional surface treatment methods. In the first tests, breakdown occurred at field strengths E/sub max/ approximately equal to 11 to 14 MV/m. The reason for the early breakdown was presumed to reside in small sites with increased losses which expand above a critical field strength. Only after a series of treatment steps in which a total of about 160 μ had been removed from the coil surface were maximum surface fields of up to E/sub max/ approximately equal to 29 MV/m and B/sub max/ approximately equal to 1050 Oe (greater than or equal to E/sub TW/ approximately equal to 4.0 MV/m) reached. Subsequently, breakdown is usually caused by electrons. A comparison of anodized and unanodized resonators showed no significant difference for the maximum attainable field strengths or in the characteristics with regard to electron loading and sensitivity to gas contamination. In two long-term tests for up to 800 h, the resonator was operated at high HF-field strengths (E/sub max/ approximately equal to 18 to 24 MV/m). An abrupt increase of e-loading, which was connected with increased resonator losses, was observed at certain time intervals. Subsequent He-conditioning for a few minutes reduced this elevated e-loading. With increasing operating time, an increase of surface losses was observed which were evidently caused by electrons impinging on the surface (radiation damage). The magnitude of the radiation damage appears to be rather uncritical for application. This radiation damage does not heal during heating to room temperature. However, light oxidative polishing suffices to eliminate the radiation damage

  4. Effect of plasma current breakaway on the operating stability of the superconducting coil of the toroidal magnetic field in the T-10M installation

    International Nuclear Information System (INIS)

    Kostenko, A.I.; Kravchenko, M.Yu.; Monoszon, N.A.; Trokhachev, G.V.

    1979-01-01

    The method and calculation results of stability of a superconducting coil of the toroidal magnetic field in the T-10M installation to plasma current breakaway are presented. The calculations were performed for two values of the magnetic field induction in the centre of the plasma cross section: 3.5 and 5 T. The calculation of energy losses and heating of the superconducting coil was performed assuming the plasma current in case of breakaway decreases to zero with an infinite rate, so that the estimations obtained are maxiaum. It is shown that in case of 3.5 T induction the superconducting coil exhibits resistance to plasma current breakaways, and in case of 5 T it is necessary to use electromagnetic screening to provide stability

  5. Line voltage distortions due to operation of the power supply devices required for plasma heating and magnetic field generation in the W7X thermonuclear fusion experiment

    International Nuclear Information System (INIS)

    Werner, F.

    1997-03-01

    The operation of the W7-X plasma heating devices requires high voltage DC power supplies with a total electrical power of 40 MVA. For this purpose twelve-pulse AC/DC converters are projected. These converters enforce a non sinusoidal line current, whose harmonics are causing corresponding line voltage distortions. To evaluate the extent of these distortions, the reaction of the harmonic currents on the AC line, is investigated by numerical network analysis. This is done for both, the 20 kV-junction point of the converters and the 110 kV-line terminal of the electricity supply company. Furthermore the design of LC series-resonant circuits, projected for power factor correction and damping of the harmonic content of the line voltage, has been verified. The additional operation of the 1.5 MVA magnet power supplies also contributes, even though to a much smaller extent, to the line voltage distortion. The influence of these twelve-pulse AC/DC converters was investigated too. The numerical calculations have been done with the aid of the network simulation program 'Pspice'. In an equivalent circuit the transmission line network and the transformers are represented by their inductances respectively equivalent inductances. The rectifier units are simulated by a number of current sources, producing the current harmonics in amplitude, frequency and phase. The harmonics amplitudes of the plasma heating power supplies are frequency and phase. The harmonics amplitudes of the plasma heating power supplies are measured values given by the manufacturer. For the magnet power supplies, the harmonics are derived from the theoretical step like I(t) current shape by Fourier series decomposition. Due to the action of the LC circuits the achieved characteristic voltage quality values are far below the permissible values corresponding to the recommendations of VDE 0160. (orig.) [de

  6. Microstructures and superconducting properties of Y-Ba-Cu and Bi-Sr-Ca-Cu oxide wires and coils prepared by the explosive compaction technique

    International Nuclear Information System (INIS)

    Hagino, S.; Suzuki, M.; Takeshita, T.; Takashima, K.; Tonda, H.

    1989-01-01

    It has been shown that explosive compaction technique can be used to densify metal, and ceramics powders and their mixtures. The authors discuss how they applied this technique to produce silver sheathed superconducting oxide wires and coils (Y-B-Cu-O and Bi-Sr-Ca-Cu-O). The wires and coils to be compacted were placed into metal tube and the tube was filled with SiC powder as a pressure propagating medium and the tube was compacted by a cylindrically axisymmetric method. The wires and coils compacted were then heat-treated in order to improve grain boundary connections of superconducting oxide crystalline grains. The oxide cores heat-treated were seen to be very dense, and a part of a Y-Ba-Cu oxide coil which was heat-treated optimally was found to have a critical current density higher than 13,000A/cm 2 at 77K

  7. A novel no-insulation winding technique of high temperature-superconducting racetrack coil for rotating applications: A progress report in Korea university.

    Science.gov (United States)

    Choi, Y H; Song, J B; Yang, D G; Kim, Y G; Hahn, S; Lee, H G

    2016-10-01

    This paper presents our recent progress on core technology development for a megawatt-class superconducting wind turbine generator supported by the international collaborative R&D program of the Korea Institute of Energy Technology Evaluation and Planning. To outperform the current high-temperature-superconducting (HTS) magnet technology in the wind turbine industry, a novel no-insulation winding technique was first proposed to develop the second-generation HTS racetrack coil for rotating applications. Here, we briefly report our recent studies on no-insulation (NI) winding technique for GdBCO coated conductor racetrack coils in the following areas: (1) Charging-discharging characteristics of no-insulation GdBCO racetrack coils with respect to external pressures applied to straight sections; (2) thermal and electrical stabilities of no-insulation GdBCO racetrack coils encapsulated with various impregnating materials; (3) quench behaviors of no-insulation racetrack coils wound with GdBCO conductor possessing various lamination layers; (4) electromagnetic characteristics of no-insulation GdBCO racetrack coils under time-varying field conditions. Test results confirmed that this novel NI winding technique was highly promising. It could provide development of a compact, mechanically dense, and self-protecting GdBCO magnet for use in real-world superconducting wind turbine generators.

  8. A novel no-insulation winding technique of high temperature-superconducting racetrack coil for rotating applications: A progress report in Korea university

    Science.gov (United States)

    Choi, Y. H.; Song, J. B.; Yang, D. G.; Kim, Y. G.; Hahn, S.; Lee, H. G.

    2016-10-01

    This paper presents our recent progress on core technology development for a megawatt-class superconducting wind turbine generator supported by the international collaborative R&D program of the Korea Institute of Energy Technology Evaluation and Planning. To outperform the current high-temperature-superconducting (HTS) magnet technology in the wind turbine industry, a novel no-insulation winding technique was first proposed to develop the second-generation HTS racetrack coil for rotating applications. Here, we briefly report our recent studies on no-insulation (NI) winding technique for GdBCO coated conductor racetrack coils in the following areas: (1) Charging-discharging characteristics of no-insulation GdBCO racetrack coils with respect to external pressures applied to straight sections; (2) thermal and electrical stabilities of no-insulation GdBCO racetrack coils encapsulated with various impregnating materials; (3) quench behaviors of no-insulation racetrack coils wound with GdBCO conductor possessing various lamination layers; (4) electromagnetic characteristics of no-insulation GdBCO racetrack coils under time-varying field conditions. Test results confirmed that this novel NI winding technique was highly promising. It could provide development of a compact, mechanically dense, and self-protecting GdBCO magnet for use in real-world superconducting wind turbine generators.

  9. Results from a model system of superconducting solenoids and phase shifting bridge for pulsed power studies for proposed tokamak EF coils

    International Nuclear Information System (INIS)

    Fuja, R.E.; Kustom, R.L.; Smith, R.P.

    1977-01-01

    A matched pair of superconducting solenoids and a phase-shifting bridge circuit has been constructed to study energy storage and transfer for application to tokamak EF coils. The intrinsically stable solenoids, each with 4 H self-inductance, incorporate sufficient cooling to allow charging at several hundred volts, corresponding to B approximately equal 1 T/sec. The three-phase inductor-convertor capacitive bridge network operating at up to 150 V rms transfers energy reversibly and at controllable rates from the storage coil to the load coil

  10. Results from a model system of superconducting solenoids and phase shifting bridge for pulsed power studies for proposed tokamak EF coils

    International Nuclear Information System (INIS)

    Fuja, R.E.; Kustom, R.L.; Smith, R.P.

    1977-01-01

    A matched pair of superconducting solenoids and a phase-shifting bridge circuit has been constructed to study energy storage and transfer for application to tokamak EF coils. The intrinsically stable solenoids, each with 4 H self-inductance, incorporate sufficient cooling to allow charging at several hundred volts, corresponding to B = 1 T/sec. The three-phase inductor-convertor capacitive bridge network operating at up to 150 V rms transfers energy reversibly and at controllable rates from the storage coil to the load coil

  11. An active magnetic bearing with high Tc superconducting coils and ferromagnetic cores

    International Nuclear Information System (INIS)

    Brown, G.V.; DiRusso, E.; Provenza, A.J.

    1996-01-01

    A proof-of-feasibility demonstration showed that high-T c , superconductor (HTS) coils can be used in a high-load, active magnetic bearing in LN 2 . A homopolar radial bearing with commercially wound HTS (Bi 2223) bias and control coils produced over 890 N (200 lb) radial load capacity (measured nonrotating) and supported a shaft to 14000 rpm. The goal was to show that HTS coils can operate stably with ferromagnetic cores in a feedback controlled system at a current density similar to that for Cu in LN 2 . The bias coil, wound with nontwisted, multifilament HTS conductor, dissipated negligible power for its direct current. The control coils, wound with monofilament HTS sheathed in Ag, dissipated negligible power for direct current. AC losses increased rapidly with frequency and quadratically with AC amplitude. Above about 2 Hz, the effective resistance of the control coils exceeds that of the silver which is in electrical parallel with the oxide superconductor. These results show that twisted multifilament conductor is not needed for stable levitation but may be desired to reduce control power for sizable dynamic loads

  12. Superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Batistoni, Paola; De Marco, Francesco; Pieroni, Leonardo [ed.

    2005-07-01

    Research on superconductivity at ENEA is mainly devoted to projects related to the ITER magnet system. In this framework, ENEA has been strongly involved in the design, manufacturing and test campaigns of the ITER toroidal field model coil (TFMC), which reached a world record in operating current (up to 80 kA). Further to this result, the activities in 2004 were devoted to optimising the ITER conductor performance. ENEA participated in the tasks launched by EFDA to define and produce industrial-scale advanced Nb3Sn strand to be used in manufacturing the ITER high-field central solenoid (CS) and toroidal field (TF) magnets. As well as contributing to the design of the new strand and the final conductor layout, ENEA will also perform characterisation tests, addressing in particular the influence of mechanical stress on the Nb3Sn performance. As a member of the international ITER-magnet testing group, ENEA plays a central role in the measurement campaigns and data analyses for each ITER-related conductor and coil. The next phase in the R and D of the ITER magnets will be their mechanical characterisation in order to define the fabrication route of the coils and structures. During 2004 the cryogenic measurement campaign on the Large Hadron Collider (LHC) by-pass diode stacks was completed. As the diode-test activity was the only LHC contract to be finished on schedule, the 'Centre Europeenne pour la Recherche Nucleaire' (CERN) asked ENEA to participate in an international tender for the cold check of the current leads for the LHC magnets. The contract was obtained, and during 2004, the experimental setup was designed and realised and the data acquisition system was developed. The measurement campaign was successfully started at the end of 2004 and will be completed in 2006.

  13. Thermal, Electrical and Mechanical Response to a Quench in Nb3Sn Superconducting Coils

    International Nuclear Information System (INIS)

    Ferracin, F.; Caspi, S.; Chiesa, L.; Gourlay, S.A.; Hafalia, R.R.; Imbasciati, L.; Lietzke, A.F.; Sabbi, G.; Scanlan, R.M.

    2003-01-01

    During a quench, significant temperatures can arise as a magnet's stored energy is dissipated in the normal zone. Temperature gradients during this process give rise to localized strains within the coil. Reactive forces in the magnet structure balance the electromagnetic and thermal forces and maintain on equilibrium. In this paper we present a complete 3D finite element analysis of a racetrack coil. Specifically, the analysis focuses on thermal, electrical and mechanical conditions in a 10 T Nb 3 Sn coil built and tested as part of LBNL's Subscale Magnet Program. The study attempts to simulate time history of the temperature and voltage rise during quench propagation. The transient thermal stress after the quench is then evaluated and discussed

  14. High magnetic field multipoles generated by superconductor magnetization within a set of nested superconducting correction coils

    International Nuclear Information System (INIS)

    Green, M.A.

    1990-04-01

    Correction elements in colliding beam accelerators such as the SSC can be the source of undesirable higher magnetic field multipoles due to magnetization of the superconductor within the corrector. Quadrupole and sextupole correctors located within the main dipole will produce sextupole and decapole due to magnetization of the superconductor within the correction coils. Lumped nested correction coils can produce a large number of skew and normal magnetization multipoles which may have an adverse effect on a stored beam at injection into a high energy colliding beam machine such as the SSC. 6 refs., 2 figs., 2 tabs

  15. Structural analysis of superconducting coils for fusion reactors taking into account the slip between conductors

    International Nuclear Information System (INIS)

    Gori, R.E.; Schrefler, B.A.

    1989-01-01

    A finite element formulation of friction effects for multilayered superconductors based on partially bonded beam systems is shown. The stiffness matrix of superconductor elements is derived, which takes into account the effects of friction between conductors. Examples relating to superconductors proposed for the NET toroidal and poloidal field coils show that the effects of slip are not negligible and should be taken into account in a structural analysis of the coil system. Also parametric studies with varying widths and heights of the insulation layer are shown

  16. A Full-size High Temperature Superconducting Coil Employed in a Wind Turbine Generator Set-up

    DEFF Research Database (Denmark)

    Song, Xiaowei (Andy); Mijatovic, Nenad; Kellers, Jürgen

    2016-01-01

    A full-size stationary experimental set-up, which is a pole pair segment of a 2 MW high temperature superconducting (HTS) wind turbine generator, has been built and tested under the HTS-GEN project in Denmark. The performance of the HTS coil is crucial to the set-up, and further to the development...... is tested in LN2 first, and then tested in the set-up so that the magnetic environment in a real generator is reflected. The experimental results are reported, followed by a finite element simulation and a discussion on the deviation of the results. The tested and estimated Ic in LN2 are 148 A and 143 A...

  17. Measurement of AC losses in a racetrack superconducting coil made from YBCO coated conductor

    DEFF Research Database (Denmark)

    Seiler, Eugen; Abrahamsen, Asger Bech; Kovac, Jan

    2012-01-01

    to reinforce it. The AC loss is measured versus the transport current Ia with the coil immersed in liquid nitrogen. Measurements at frequencies 21 Hz, 36 Hz and 72 Hz are compared. The AC losses follow I2 a dependence at low current amplitudes and I3 a at high amplitudes. After cutting the inner steel frame...

  18. Magnetic configuration effects on the edge heat flux in the limiter plasma on W7-X measured using the infrared camera and the combined probe

    Science.gov (United States)

    P, DREWS; H, NIEMANN; J, COSFELD; Y, GAO; J, GEIGER; O, GRULKE; M, HENKEL; D, HÖSCHEN; K, HOLLFELD; C, KILLER; A, KRÄMER-FLECKEN; Y, LIANG; S, LIU; D, NICOLAI; O, NEUBAUER; M, RACK; B, SCHWEER; G, SATHEESWARAN; L, RUDISCHHAUSER; N, SANDRI; N, WANG; the W7-X Team

    2018-05-01

    Controlling the heat and particle fluxes in the plasma edge and on the plasma facing components is important for the safe and effective operation of every magnetically confined fusion device. This was attempted on Wendelstein 7-X in the first operational campaign, with the modification of the magnetic configuration by use of the trim coils and tuning the field coil currents, commonly named iota scan. Ideally, the heat loads on the five limiters are equal. However, they differ between each limiter and are non-uniform, due to the (relatively small) error fields caused by the misalignment of components. It is therefore necessary to study the influence of the configuration changes on the transport of heat and particles in the plasma edge caused by the application of error fields and the change of the magnetic configuration. In this paper the up-stream measurements conducted with the combined probe are compared to the downstream measurements with the DIAS infrared camera on the limiter.

  19. Development of special machines for production of large number of superconducting coils for the spool correctors for the main dipole of LHC

    International Nuclear Information System (INIS)

    Puntambekar, A.M.; Karmarkar, M.G.

    2003-01-01

    Superconducting (Sc) spool correctors of different types namely Sextupole, (MCS) Decapole (MCD) and Octupole (MCO) are incorporated in each of the main dipole of Large Hadron Collider (LHC). In all 2464 MCS and 1232 MCDO magnets are required to equip all 1232 Dipoles of LHC. The coils wound from thin rectangular section Sc wires are the heart of magnet assembly and its performance for the field quality and cold quench training largely depends on the precise and robust construction of these coils. Under DAE-CERN collaboration CAT was entrusted with the responsibility of making these magnets for LHC. Starting with development of manual fixtures and prototyping using soldering, a more advances special Automatic Coils Winding and Ultrasonic Welding (USW) system for production of large no. of coils and magnets were built at CAT. The paper briefly describes the various developments in this area. (author)

  20. Influence of the spacers on the stability of channel cooled superconducting coils

    International Nuclear Information System (INIS)

    Meuris, C.

    1980-10-01

    In a previous paper, the thermal stability of channel cooled superconducting magnets was experimentally studied. Stable normal zones were observed within a range of currents and local disturbance energies. Usual theories fail to fully explain these results, owing to the fact that they take into account a heat transfer to liquid helium only function of the temperature of the conductor, whatever the position is. In a simplified theoretical analysis, it is shown that in a locally uncooled superconducting wire several stationary normal zones can exist. A criterion is derived that yields the recovery current as a function of the length of the uncooled region. Besides, a detailed numerical analysis determines the evolution of a normal zone in a channel cooled magnet. Theoretical calculations are compared with experimental results

  1. Superconducting Quadrupoles for the ISR High Luminosity insertion Coil cross section

    CERN Multimedia

    1978-01-01

    This picture shows a cut out section of an ISR High Luminosity (low beta) Quadrupole. One can clearly see the distribution of conductors and spacers which produces the wanted quadrupolar field. The spacers are made of pure copper and the central pole of stainless steel.The superconducting wire may be seen in photo 8008591X. See also pictures 7702690X, 8008591X, 7702698X.

  2. Superconductivity

    International Nuclear Information System (INIS)

    Taylor, A.W.B.; Noakes, G.R.

    1981-01-01

    This book is an elementray introduction into superconductivity. The topics are the superconducting state, the magnetic properties of superconductors, type I superconductors, type II superconductors and a chapter on the superconductivity theory. (WL)

  3. Comparison of AC losses, magnetic field/current distributions and critical currents of superconducting circular pancake coils and infinitely long stacks using coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Yuan Weijia; Campbell, A M; Hong, Z; Ainslie, M D; Coombs, T A, E-mail: wy215@cam.ac.u [Electronic, Power and Energy Conversion Group, Electrical Engineering Division, Engineering Department, University of Cambridge, Cambridge CB3 0FA (United Kingdom)

    2010-08-15

    A model is presented for calculating the AC losses, magnetic field/current density distribution and critical currents of a circular superconducting pancake coil. The assumption is that the magnetic flux lines will lie parallel to the wide faces of tapes in the unpenetrated area of the coil. Instead of using an infinitely long stack to approximate the circular coil, this paper gives an exact circular coil model using elliptic integrals. A new efficient numerical method is introduced to yield more accurate and fast computation. The computation results are in good agreement with the assumptions. For a small value of the coil radius, there is an asymmetry along the coil radius direction. As the coil radius increases, this asymmetry will gradually decrease, and the AC losses and penetration depth will increase, but the critical current will decrease. We find that if the internal radius is equal to the winding thickness, the infinitely long stack approximation overestimates the loss by 10% and even if the internal radius is reduced to zero, the error is still only 60%. The infinitely long stack approximation is therefore adequate for most practical purposes. In addition, the comparison result shows that the infinitely long stack approximation saves computation time significantly.

  4. 3D Cones Acquisition of Human Extremity Imaging Using a 1.5T Superconducting Magnet and an Unshielded Gradient Coil Set.

    Science.gov (United States)

    Setoi, Ayana; Kose, Katsumi

    2018-05-16

    We developed ultrashort echo-time (UTE) imaging sequences with 3D Cones trajectories for a home-built compact MRI system using a 1.5T superconducting magnet and an unshielded gradient coil set. We achieved less than 7 min imaging time and obtained clear in vivo images of a human forearm with a TE of 0.4 ms. We concluded that UTE imaging using 3D Cones acquisition was successfully implemented in our 1.5T MRI system.

  5. Superconductivity

    CERN Document Server

    Poole, Charles P; Farach, Horacio A

    1995-01-01

    Superconductivity covers the nature of the phenomenon of superconductivity. The book discusses the fundamental principles of superconductivity; the essential features of the superconducting state-the phenomena of zero resistance and perfect diamagnetism; and the properties of the various classes of superconductors, including the organics, the buckministerfullerenes, and the precursors to the cuprates. The text also describes superconductivity from the viewpoint of thermodynamics and provides expressions for the free energy; the Ginzburg-Landau and BCS theories; and the structures of the high

  6. Iberdrola project engineering in the manufacture of the ITER superconducting coils

    International Nuclear Information System (INIS)

    Felipe, A.; Merino, A.

    2012-01-01

    ITER in a large-scale project that aims to demonstrate that it is possible to produce commercial energy from fusion. During its operational lifetime, ITER will test key technologies necessary for the next step: the demonstration fusion power plant that will prove that it is possible to capture fusion energy for commercial use. IBERDROLA Ingenieria y Construccion is the leader of a Consortium with ASG superconductors (Italy) and Elytt Energy (Spain) that is in charge of the manufacturing of one of the most relevant component: 10 Toroidal Field Coils. the development of this project presents significant technological challenges, where the main processes are the one related to high accuracy required during all manufacturing processes. (Author)

  7. Superconductivity

    International Nuclear Information System (INIS)

    Langone, J.

    1989-01-01

    This book explains the theoretical background of superconductivity. Includes discussion of electricity, material fabrication, maglev trains, the superconducting supercollider, and Japanese-US competition. The authors reports the latest discoveries

  8. Superconductivity

    International Nuclear Information System (INIS)

    Onnes, H.K.

    1988-01-01

    The author traces the development of superconductivity from 1911 to 1986. Some of the areas he explores are the Meissner Effect, theoretical developments, experimental developments, engineering achievements, research in superconducting magnets, and research in superconducting electronics. The article also mentions applications shown to be technically feasible, but not yet commercialized. High-temperature superconductivity may provide enough leverage to bring these applications to the marketplace

  9. W7-AS/W7-X contributions to the 19th European conference on controlled fusion and plasma heating (Innsbruck, June 29 to July 3, 1992). - W7-AS contributions to the 10th PSI conference (Monterey, USA, March 30 to April 3, 1992)

    International Nuclear Information System (INIS)

    1992-07-01

    This paper contains 24 contributions with the following topics: Current drive and bootstrap current in stellators; Statistical analysis of luminescence signals obbserved during pellet injection; Density fluctuation measurements by broadband heterodyne reflectometry on the W7-AS stellarator; Measurements of electron cyclotron emission during high power ECRH in the W7-AS stellarator; Density, potential and temperature fluctuation in Wendelstein 7-AS; Measurement of coherent temperature fluctuation on the stellarator Wendelstein 7-AS (W7-AS); Localized impurity flux measurements on W7-AS; The optimum ion confinement mode in W7-A stellarator induced by fast ion orbit losses of the nearly perpendicular NBI; Electron heat transport in the LMFP-regime for the stellators W7-A, W7-AS and L2; Diffusive and connective transport modelling from analysis of ECRH-stimulated electron heat wave propagation; Modified vacuum fields and compensation of islands for the stellarator W7-AS; Towards higher β in the stellarator W7-AS; Influence of electric fields on the heating efficiency in the W7-AS stellarator; Mode activity at high plasma pressure in the stellarator W7-AS; Sniffer probe measurements in W7-AS; Local neutral particle density in the W7-AS stellarator; A general solution of the ripple-averaged kinetic equation (GSRAKE); Progress in the studies of URAGAN-2M stability and transport properties; Optimization of coils and sweep coil system for W-7-X; On stationary flow in the boundary region of toroidal system; Finite ion gyro radius stabilization of ideal MHD ballooning modes in optimized stellarators; Bulk-boronized operation in the W7-AS stellarator; The impact of boundary plasma conditions on the plasma performance; Transport study on the boundary plasma of the W7-AS. (orig./MM)

  10. Superconductivity

    International Nuclear Information System (INIS)

    Andersen, N.H.; Mortensen, K.

    1988-12-01

    This report contains lecture notes of the basic lectures presented at the 1st Topsoee Summer School on Superconductivity held at Risoe National Laboratory, June 20-24, 1988. The following lecture notes are included: L.M. Falicov: 'Superconductivity: Phenomenology', A. Bohr and O. Ulfbeck: 'Quantal structure of superconductivity. Gauge angle', G. Aeppli: 'Muons, neutrons and superconductivity', N.F. Pedersen: 'The Josephson junction', C. Michel: 'Physicochemistry of high-T c superconductors', C. Laverick and J.K. Hulm: 'Manufacturing and application of superconducting wires', J. Clarke: 'SQUID concepts and systems'. (orig.) With 10 tabs., 128 figs., 219 refs

  11. Superconductivity

    International Nuclear Information System (INIS)

    Palmieri, V.

    1990-01-01

    This paper reports on superconductivity the absence of electrical resistance has always fascinated the mind of researchers with a promise of applications unachievable by conventional technologies. Since its discovery superconductivity has been posing many questions and challenges to solid state physics, quantum mechanics, chemistry and material science. Simulations arrived to superconductivity from particle physics, astrophysic, electronics, electrical engineering and so on. In seventy-five years the original promises of superconductivity were going to become reality: a microscopical theory gave to superconductivity the cloth of the science and the level of technological advances was getting higher and higher. High field superconducting magnets became commercially available, superconducting electronic devices were invented, high field accelerating gradients were obtained in superconductive cavities and superconducting particle detectors were under study. Other improvements came in a quiet progression when a tornado brought a revolution in the field: new materials had been discovered and superconductivity, from being a phenomenon relegated to the liquid Helium temperatures, became achievable over the liquid Nitrogen temperature. All the physics and the technological implications under superconductivity have to be considered ab initio

  12. Superconductivity

    CERN Document Server

    Thomas, D B

    1974-01-01

    A short general review is presented of the progress made in applied superconductivity as a result of work performed in connection with the high-energy physics program in Europe. The phenomenon of superconductivity and properties of superconductors of Types I and II are outlined. The main body of the paper deals with the development of niobium-titanium superconducting magnets and of radio-frequency superconducting cavities and accelerating structures. Examples of applications in and for high-energy physics experiments are given, including the large superconducting magnet for the Big European Bubble Chamber, prototype synchrotron magnets for the Super Proton Synchrotron, superconducting d.c. beam line magnets, and superconducting RF cavities for use in various laboratories. (0 refs).

  13. Designing stellarator coils by a modified Newton method using FOCUS

    Science.gov (United States)

    Zhu, Caoxiang; Hudson, Stuart R.; Song, Yuntao; Wan, Yuanxi

    2018-06-01

    To find the optimal coils for stellarators, nonlinear optimization algorithms are applied in existing coil design codes. However, none of these codes have used the information from the second-order derivatives. In this paper, we present a modified Newton method in the recently developed code FOCUS. The Hessian matrix is calculated with analytically derived equations. Its inverse is approximated by a modified Cholesky factorization and applied in the iterative scheme of a classical Newton method. Using this method, FOCUS is able to recover the W7-X modular coils starting from a simple initial guess. Results demonstrate significant advantages.

  14. Superconductivity

    International Nuclear Information System (INIS)

    Kakani, S.L.; Kakani, Shubhra

    2007-01-01

    The monograph provides readable introduction to the basics of superconductivity for beginners and experimentalists. For theorists, the monograph provides nice and brief description of the broad spectrum of experimental properties, theoretical concepts with all details, which theorists should learn, and provides a sound basis for students interested in studying superconducting theory at the microscopic level. Special chapter on the theory of high-temperature superconductivity in cuprates is devoted

  15. A novel approach to calculate inductance and analyze magnetic flux density of helical toroidal coil applicable to Superconducting Magnetic Energy Storage systems (SMES)

    International Nuclear Information System (INIS)

    Alizadeh Pahlavani, M.R.; Shoulaie, A.

    2010-01-01

    In this paper, formulas are proposed for the self and mutual inductance calculations of the helical toroidal coil (HTC) by the direct and indirect methods at superconductivity conditions. The direct method is based on the Neumann's equation and the indirect approach is based on the toroidal and the poloidal components of the magnetic flux density. Numerical calculations show that the direct method is more accurate than the indirect approach at the expense of its longer computational time. Implementation of some engineering assumptions in the indirect method is shown to reduce the computational time without loss of accuracy. Comparison between the experimental measurements and simulated results for inductance, using the direct and the indirect methods indicates that the proposed formulas have high reliability. It is also shown that the self inductance and the mutual inductance could be calculated in the same way, provided that the radius of curvature is >0.4 of the minor radius, and that the definition of the geometric mean radius in the superconductivity conditions is used. Plotting contours for the magnetic flux density and the inductance show that the inductance formulas of helical toroidal coil could be used as the basis for coil optimal design. Optimization target functions such as maximization of the ratio of stored magnetic energy with respect to the volume of the toroid or the conductor's mass, the elimination or the balance of stress in some coordinate directions, and the attenuation of leakage flux could be considered. The finite element (FE) approach is employed to present an algorithm to study the three-dimensional leakage flux distribution pattern of the coil and to draw the magnetic flux density lines of the HTC. The presented algorithm, due to its simplicity in analysis and ease of implementation of the non-symmetrical and three-dimensional objects, is advantageous to the commercial software such as ANSYS, MAXWELL, and FLUX. Finally, using the

  16. Superconductivity

    International Nuclear Information System (INIS)

    Caruana, C.M.

    1988-01-01

    Despite reports of new, high-temperature superconductive materials almost every day, participants at the First Congress on Superconductivity do not anticipate commercial applications with these materials soon. What many do envision is the discovery of superconducting materials that can function at much warmer, perhaps even room temperatures. Others hope superconductivity will usher in a new age of technology as semiconductors and transistors did. This article reviews what the speakers had to say at the four-day congress held in Houston last February. Several speakers voiced concern that the Reagan administration's apparent lack of interest in funding superconductivity research while other countries, notably Japan, continue to pour money into research and development could hamper America's international competitiveness

  17. Performance of cold compressors in a cooling system of an R and D superconducting coil cooled with subcooled helium

    International Nuclear Information System (INIS)

    Hamaguchi, S.; Imagawa, S.; Yanagi, N.; Takahata, K.; Maekawa, R.; Mito, T.

    2006-01-01

    The helical coils of large helical device (LHD) have been operated in saturated helium at 4.4 K and plasma experiments have been carried out at magnetic fields lower than 3 T for 8 years. Now, it is considered that the cooling system of helical coils will be improved to enhance magnetic fields in 2006. In the improvement, the helical coils will be cooled with subcooled helium and the operating temperature of helical coils will be lowered to achieve the designed field of 3 T and enhance cryogenic stabilities. Two cold compressors will be used in the cooling system of helical coils to generate subcooled helium. In the present study, the performance of cold compressors has been investigated, using a cooling system of R and D coil, to apply cold compressors to the cooling system of helical coils. Actual surge lines of cold compressors were observed and the stable operation area was obtained. Automatic operations were also performed within the area. In the automatic operations, the suitable pressure of a saturated helium bath, calculated from the rotation speed of the 1st cold compressor, was regulated by bypass valve. From these results, stable operations will be expected in the cooling system of helical coils

  18. Low-Cost Superconducting Wire for Wind Generators: High Performance, Low Cost Superconducting Wires and Coils for High Power Wind Generators

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-01-01

    REACT Project: The University of Houston will develop a low-cost, high-current superconducting wire that could be used in high-power wind generators. Superconducting wire currently transports 600 times more electric current than a similarly sized copper wire, but is significantly more expensive. The University of Houston’s innovation is based on engineering nanoscale defects in the superconducting film. This could quadruple the current relative to today’s superconducting wires, supporting the same amount of current using 25% of the material. This would make wind generators lighter, more powerful and more efficient. The design could result in a several-fold reduction in wire costs and enable their commercial viability of high-power wind generators for use in offshore applications.

  19. Superconductivity

    CERN Document Server

    Ketterson, John B

    2008-01-01

    Conceived as the definitive reference in a classic and important field of modern physics, this extensive and comprehensive handbook systematically reviews the basic physics, theory and recent advances in the field of superconductivity. Leading researchers, including Nobel laureates, describe the state-of-the-art in conventional and unconventional superconductors at a particularly opportune time, as new experimental techniques and field-theoretical methods have emerged. In addition to full-coverage of novel materials and underlying mechanisms, the handbook reflects continued intense research into electron-phone based superconductivity. Considerable attention is devoted to high-Tc superconductivity, novel superconductivity, including triplet pairing in the ruthenates, novel superconductors, such as heavy-Fermion metals and organic materials, and also granular superconductors. What’s more, several contributions address superconductors with impurities and nanostructured superconductors. Important new results on...

  20. New method to design stellarator coils without the winding surface

    Science.gov (United States)

    Zhu, Caoxiang; Hudson, Stuart R.; Song, Yuntao; Wan, Yuanxi

    2018-01-01

    Finding an easy-to-build coils set has been a critical issue for stellarator design for decades. Conventional approaches assume a toroidal ‘winding’ surface, but a poorly chosen winding surface can unnecessarily constrain the coil optimization algorithm, This article presents a new method to design coils for stellarators. Each discrete coil is represented as an arbitrary, closed, one-dimensional curve embedded in three-dimensional space. A target function to be minimized that includes both physical requirements and engineering constraints is constructed. The derivatives of the target function with respect to the parameters describing the coil geometries and currents are calculated analytically. A numerical code, named flexible optimized coils using space curves (FOCUS), has been developed. Applications to a simple stellarator configuration, W7-X and LHD vacuum fields are presented.

  1. Active internal corrector coils

    International Nuclear Information System (INIS)

    Thompson, P.A.; Cottingham, J.; Dahl, P.

    1986-01-01

    Trim or corrector coils to correct main magnet field errors and provide higher multipole fields for beam optics purposes are a standard feature of superconducting magnet accelerator systems. This paper describes some of the design and construction features of powered internal trim coils and a sampling of the test results obtained

  2. Superconductivity

    CERN Document Server

    Poole, Charles P; Creswick, Richard J; Prozorov, Ruslan

    2014-01-01

    Superconductivity, Third Edition is an encyclopedic treatment of all aspects of the subject, from classic materials to fullerenes. Emphasis is on balanced coverage, with a comprehensive reference list and significant graphics from all areas of the published literature. Widely used theoretical approaches are explained in detail. Topics of special interest include high temperature superconductors, spectroscopy, critical states, transport properties, and tunneling. This book covers the whole field of superconductivity from both the theoretical and the experimental point of view. This third edition features extensive revisions throughout, and new chapters on second critical field and iron based superconductors.

  3. Eccentric Coil Test Facility (ECTF)

    International Nuclear Information System (INIS)

    Burn, P.B.; Walstrom, P.L.; Anderson, W.C.; Marguerat, E.F.

    1975-01-01

    The conceptual design of a facility for testing superconducting coils under some conditions peculiar to tokamak systems is given. A primary element of the proposed facility is a large 25 MJ background solenoid. Discussions of the mechanical structure, the stress distribution and the thermal stability for this coil are included. The systems for controlling the facility and diagnosing test coil behavior are also described

  4. Stress analysis of the conceptual design configurations of constant tension D-shaped superconducting toroidal field coils for TNS

    International Nuclear Information System (INIS)

    Fernades, R.; Smith, R.A.

    1977-01-01

    Conceptual design configurations of D-shaped toroidal field coils applicable to the TNS program are studied under the action of the toroidal field loading condition and the vertical field loading condition, but not the fault condition. Although the analysis is specific to an 8 Tesla design using a niobium titanium superconductor, the results can be extended to a coil with a different conductor material and subjected to a field of different magnitude provided the condition of linear elasticity is not violated. The analysis technique used is the finite element method, with three dimensional finite elements defined in the ANSYS computer code, and supplemented by closed form analytical solutions

  5. Mathematical model to determine the dimensions of superconducting cylindrical coils with a given central field – the case study for MgB{sub 2} conductors with isotropic I{sub c}(B) characteristic

    Energy Technology Data Exchange (ETDEWEB)

    Pitel, Jozef, E-mail: jozef.pitel@savba.sk [Institute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská 9, 841 04 Bratislava (Slovakia); Melišek, Tibor [Institute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská 9, 841 04 Bratislava (Slovakia); Tropeano, Matteo; Nardelli, Davide; Tumino, Andrea [Columbus Superconductors, Via delle Terre Rosse 30, I-16133 Genova (Italy)

    2016-08-15

    Highlights: • Influence of the winding geometry on central field of cylindrical coils is studied. • Procedure to determine dimensions of coils with a given central field is developed. • The model is applied to MgB{sub 2}/Ni/Cu conductors with isotropic I{sub c}(B) characteristic. • Influence of the thickness of stabilizing copper on coil parameters is analyzed. • Optimization with respect to coil operating current and wire length is discussed. - Abstract: In this work, we present a mathematical model which enables to design cylindrical coils with a given central field, made of the superconducting conductor with isotropic I{sub c}(B) characteristic. The model results in a computer code that enables to find out the coil dimensions, and to calculate the coil parameters such as critical current, maximum field in the winding and field non-uniformity on the coil axis. The I{sub c}(B) characteristic of the conductor is represented by the set of data measured in discrete points. This approach allows us to express the I{sub c}(B) as a function linearized in parts. Then, it is possible to involve the central field of the coil, coil dimensions, and parameters of the conductor, including its I{sub c}(B) characteristic, in one equation which can be solved using ordinary numerical non-linear methods. Since the coil dimensions and conductor parameters are mutually linked in one equation with respect to a given coil central field, it is possible to analyze an influence of one parameter on the other one. The model was applied to three commercially available MgB{sub 2}/Ni/Cu conductors produced by Columbus Superconductors. The results of simulations with the I{sub c}(B) data at 20 K illustrate that there exists a set of winding geometries that generate a required central field, changing from a disc shape to long thin solenoid. Further, we analyze how the thickness of stabilizing copper influences the coil dimensions, overall conductor length, coil critical current, maximum

  6. Superconductivity

    International Nuclear Information System (INIS)

    Narlikar, A.V.

    1993-01-01

    Amongst the numerous scientific discoveries that the 20th century has to its credit, superconductivity stands out as an exceptional example of having retained its original dynamism and excitement even for more than 80 years after its discovery. It has proved itself to be a rich field by continually offering frontal challenges in both research and applications. Indeed, one finds that a majority of internationally renowned condensed matter theorists, at some point of their career, have found excitement in working in this important area. Superconductivity presents a unique example of having fetched Nobel awards as many as four times to date, and yet, interestingly enough, the field still remains open for new insights and discoveries which could undeniably be of immense technological value. 1 fig

  7. Superconductivity

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    This book profiles the research activity of 42 companies in the superconductivity field, worldwide. It forms a unique and comprehensive directory to this emerging technology. For each research site, it details the various projects in progress, analyzes the level of activity, pinpoints applications and R and D areas, reviews strategies and provides complete contact information. It lists key individuals, offers international comparisons of government funding, reviews market forecasts and development timetables and features a bibliography of selected articles on the subject

  8. Superconductivity

    International Nuclear Information System (INIS)

    Buller, L.; Carrillo, F.; Dietert, R.; Kotziapashis, A.

    1989-01-01

    Superconductors are materials which combine the property of zero electric resistance with the capability to exclude any adjacent magnetic field. This leads to many large scale applications such as the much publicized levitating train, generation of magnetic fields in MHD electric generators, and special medical diagnostic equipment. On a smaller-scale, superconductive materials could replace existing resistive connectors and decrease signal delays by reducing the RLC time constants. Thus, a computer could operate at much higher speeds, and consequently at lower power levels which would reduce the need for heat removal and allow closer spacing of circuitry. Although technical advances and proposed applications are constantly being published, it should be recognized that superconductivity is a slowly developing technology. It has taken scientists almost eighty years to learn what they now know about this material and its function. The present paper provides an overview of the historical development of superconductivity and describes some of the potential applications for this new technology as it pertains to the electronics industry

  9. Superconductivity

    International Nuclear Information System (INIS)

    2007-01-01

    During 2007, a large amount of the work was centred on the ITER project and related tasks. The activities based on low-temperature superconducting (LTS) materials included the manufacture and qualification of ITER full-size conductors under relevant operating conditions, the design of conductors and magnets for the JT-60SA tokamak and the manufacture of the conductors for the European dipole facility. A preliminary study was also performed to develop a new test facility at ENEA in order to test long-length ITER or DEMO full-size conductors. Several studies on different superconducting materials were also started to create a more complete database of superconductor properties, and also for use in magnet design. In this context, an extensive measurement campaign on transport and magnetic properties was carried out on commercially available NbTi strands. Work was started on characterising MgB 2 wire and bulk samples to optimise their performance. In addition, an intense experimental study was started to clarify the effect of mechanical loads on the transport properties of multi-filamentary Nb 3 Sn strands with twisted or untwisted superconducting filaments. The experimental activity on high-temperature superconducting (HTS) materials was mainly focussed on the development and characterisation of YBa 2 Cu 3 O 7-X (YBCO) based coated conductors. Several characteristics regarding YBCO deposition, current transport performance and tape manufacture were investigated. In the framework of chemical approaches for YBCO film growth, a new method, developed in collaboration with the Technical University of Cluj-Napoca (TUCN), Romania, was studied to obtain YBCO film via chemical solution deposition, which modifies the well-assessed metallic organic deposition trifluoroacetate (MOD-TFA) approach. The results are promising in terms of critical current and film thickness values. YBCO properties in films with artificially added pinning sites were characterised in collaboration with

  10. Large coil task and results of testing US coils

    International Nuclear Information System (INIS)

    Haubenreich, P.N.

    1986-01-01

    The United States, EURATOM, Japan, and Switzerland have collaborated since 1978 in development of superconducting toroidal field coils for fusion reactor applications. The United States provided a test facility nd three coils; the other participants, one coil each. All coils have the same interface dimensions and performance requirements (stable at 8 T), but internal design was decided by each team. Two US coil teams chose bath-cooled NbTi, 10-kA conductors. One developed a Nb 3 Sn conductor, cooled by internal flow, rated at 18 kA. All US coils have diagnostic instrumentation and imbedded heaters that enable stability tests and simulated nuclear heating experiments. In single-coil tests, each coil operated at full current in self-field (6.4 T). In six-coil tests that began in July 1986, one US coil and the Japanese coil hve been successfully operated at full current at 8 T. The other coils have operated as background coils while awaiting their turn as test coil. Coil tests have been informative and results gratifying. The facility has capably supported coil testing and its operation has provided information that will be useful in designing future fusion systems. Coil capabilities beyond nominal design points will be determined

  11. Effect of a superconducting coil as a fault current limiter on current density distribution in BSCCO tape after an over-current pulse

    International Nuclear Information System (INIS)

    Tallouli, M; Yamaguchi, S.; Shyshkin, O.

    2017-01-01

    The development of power transmission lines based on long-length high temperature superconducting (HTS) tapes is complicated and technically challenging task. A serious problem for transmission line operation could become HTS power cable damage due to over-current pulse conditions. To avoid the cable damage in any urgent case the superconducting coil technology, i.e. superconductor fault current limiter (SFCL) is required. Comprehensive understanding of the current density characteristics of HTS tapes in both cases, either after pure over-current pulse or after over-current pulse limited by SFCL, is needed to restart or to continue the operation of the power transmission line. Moreover, current density distribution along and across the HTS tape provides us with the sufficient information about the quality of the tape performance in different current feeding regimes. In present paper we examine BSCCO HTS tape under two current feeding regimes. The first one is 100A feeding preceded by 900A over-current pulse. In this case none of tape protection was used. The second scenario is similar to the fist one but SFCL is used to limit an over-current value. For both scenarios after the pulse is gone and the current feeding is set up at 100A we scan magnetic field above the tape by means of Hall probe sensor. Then the feeding is turned of and the magnetic field scanning is repeated. Using the inverse problem numerical solver we calculate the corresponding direct and permanent current density distributions during the feeding and after switch off. It is demonstrated that in the absence of SFCL the current distribution is highly peaked at the tape center. At the same time the current distribution in the experiment with SFCL is similar to that observed under normal current feeding condition. The current peaking in the first case is explained by the effect of an opposite electric field induced at the tape edges during the overcurrent pulse decay, and by degradation of

  12. Two tests of electric fields, second-order in source-velocity terms of closed, steady currents: (1) an electron beam; (2) a superconducting coil

    International Nuclear Information System (INIS)

    Kenyon, C.S.

    1980-01-01

    One particular prediction of Maxwell's theory that has been previously neglected is that the motion of charges traveling in closed loops produces no constant electric fields. This study presents and analyzes the results of two new experiments designed to test for second-order, source-velocity electric fields from steady, closed currents and analyzes another experiment in light of these fields. The first experiment employed an electron beam. The second used a niobium-titanium coil designed so that the voltage measurement configuration could be easily switched from a Faraday to a non-faraday configuration between sets of runs. The implications of the observation of a null charge on magnetically suspended superconducting spheres vis-a-vis the second-order, source-velocity fields were discussed as the third case. The observation of a null potential corresponding to a null effective charge from a hypothetical velocity-squared field in both the beam and the coil experiment placed the upper bound on a field term at 0.02 with respect a Coulomb term. An observed null charge on the suspended spheres reduced this bound to 0.001. Such an upper bound is strong evidence against alternative theories predicting a relative contribution of the order of unity for a simple velocity-squared term. A simple velocity-squared electric field would be indistinguishable from a velocity-squared charge variation. The latter test limits such a charge variation to 0.001 of the total charge. The suspended-spheres test allowed the previously neglected issue of a general second-order, source-velocity electric field to be addressed. The observed null charge in this test contradicts and thus eliminates a hypothesized, general, electric field expression containing three second-order, source-velocity terms

  13. LHC bending magnet coil

    CERN Multimedia

    A short test version of coil of wire used for the LHC dipole magnets. The high magnetic fields needed for guiding particles around the Large Hadron Collider (LHC) ring are created by passing 12’500 amps of current through coils of superconducting wiring. At very low temperatures, superconductors have no electrical resistance and therefore no power loss. The LHC is the largest superconducting installation ever built. The magnetic field must also be extremely uniform. This means the current flowing in the coils has to be very precisely controlled. Indeed, nowhere before has such precision been achieved at such high currents. Magnet coils are made of copper-clad niobium–titanium cables — each wire in the cable consists of 9’000 niobium–titanium filaments ten times finer than a hair.

  14. Conceptual design of a superconducting coil system cooled by forced flow HE II for the central column of net

    International Nuclear Information System (INIS)

    Ciazynski, D.; Duchateau, J.L.; Turck, B.

    1987-01-01

    In order to increase the maximum flux sweep, a present trend is to design ohmic coils producing fields as high as II teslas. In Niobium-Titanium, critical current densities of 10 9 A/m 2 at 1.8 K under a field of 11 teslas are now claimed by several manufacturers. This in addition enables to make use of the outstanding cooling properties of He II. The forced flow technics can again be envisaged for He II to remove the heat load. Two solutions are investigated. The first one uses a 40 kA cable wound in double pancakes. The second one makes use of several conductors layer wound and current supplied in parallel

  15. Method and apparatus for balancing the magnetic field detecting loops of a cryogenic gradiometer using trimming coils and superconducting disks

    International Nuclear Information System (INIS)

    Lutes, C.L.

    1982-01-01

    An apparatus for and a method of measuring the difference in intensity between two coplanar magnetic field vector components at two different points in space. The device is comprised of two interconnected, relatively large, loop patterns of opposite, flux cancelling, winding sense. One or both loops include a trimming element that is itself formed of two interconnected, relatively small, loop patterns of opposite, flux cancelling, winding sense. The device is analyzed for imbalance between the two large loops and is then balanced by placing a balancing superconducting disk of the proper characteristic in or near one of the two small loops of the trimming element. The so-trimmed apparatus forms a gradiometer of substantially improved mensuration

  16. Development of superconducting equipment for fusion device

    International Nuclear Information System (INIS)

    Konno, Masayuki; Ueda, Toshio; Hiue, Hisaaki; Ohgushi, Kouzou

    1993-01-01

    At Fuji Electric Co., Ltd., the development of superconductivity was started from 1960, and superconducting equipment for fusion device has been developed for ten years. The superconducting equipment, which is developed for fusion by Fuji Electric Co., Ltd., are able to be grouped in three categories which are current lead, superconducting coil and superconducting bus-line. The current lead is an electrical feeder between a superconducting coil and an electrical power supply. The rated current of developed current lead is 30kA at continuous use and 100kA at short time use respectively. The advanced disk type coil is developed for the toroidal field coil and some coils are developed for critical current measurement. Superconductor is applied to the superconducting bus-line between the superconducting coils and the current leads, and the bus-line is being developed for the Large Helical Device. This report describes an abstract of these equipment. (author)

  17. Study of superconducting Nb{sub 3}Sn coils; Etude de bobinages supraconducteurs en Nb{sub 3}Sn

    Energy Technology Data Exchange (ETDEWEB)

    Vivet, B

    1963-07-01

    Composite superconducting Nb{sub 3}Sn wires with a diameter of 0.5 mm and a length of about 100 m were made, and Hc-Ic diagrams were plotted up to fields of 80 kgauss for short lengths. Two solenoids producing fields of about 20 kgauss were studied. Nb{sub 3}Sn solenoids, as opposed to those of Nb-Zr or Nb-Ti, appear to have a predictable behavior. Solenoids with less insulation produced stronger fields than heavily insulated solenoids. (author) [French] Une etude des fils composites supraconducteurs de Nb{sub 3}Sn a ete entreprise au C.E.N. Saclay, en collaboration avec la Societe S.O.D.E.R.X. Des fils de 0,5 mm de diametre et d'une centaine de metres de longueur ont ete produits de facon experimentale. Des diagrammes Hc-Ic ont pu etre traces, jusqu'en des champs de 80 kG, sur des echantillons de petite longueur. Deux solenoides ont ete etudies produisant les champs de l'ordre de 20 kg. Il semble que, contrairement aux alliages Nb-Zr ou Nb-Ti, les solenoides en Nb{sub 3}Sn aient un comportement previsible d'apres les tests sur des echantillons courts. On montrera d'autre part qu'un bobinage a faible isolement peut produire un champ notablement plus eleve qu'un bobinage isole. Une production plus extensive permettra, dans les semaines a venir, la fabrication de solenoides de plus grosse dimension et produisant des champs plus eleves. (auteur)

  18. Startup of large coil test facility

    International Nuclear Information System (INIS)

    Haubenreich, P.N.; Bohanan, R.E.; Fietz, W.A.; Luton, J.N.; May, J.R.

    1984-01-01

    The Large Coil Test Facility (LCTF) is being used to test superconducting toroidal field coils about one-third the size of those for INTOR. Data were obtained on performance of refrigerator, helium distribution, power supplies, controls, and data acquisition systems and on the acoustic emission, voltages, currents, and mechanical strains during charging and discharging the coils. (author)

  19. Supporting device for Toroidal coils

    International Nuclear Information System (INIS)

    Araki, Takao.

    1985-01-01

    Purpose: To reduce the response of a toroidal coil supporting device upon earthquakes and improve the earthquake proofness in a tokamak type thermonuclear device. Constitution: Structural materials having large longitudinal modulus and enduring great stresses, for example, stainless steels are used as the toroidal coil supporting legs and heat insulating structural materials are embedded in a nuclear reactor base mats below the supporting legs. Furthermore, heat insulating concretes are spiked around the heat insulating structural materials to prevent the intrusion of heat to the toroidal coils. The toroidal coils are kept at cryogenic state and superconductive state for the conductors. In this way, the period of proper vibrations of the toroidal coils and the toroidal coil supporting structures can be shortened thereby decreasing the seismic response. Furthermore, since the strength of the supporting legs is increased, the earthquake proofness of the coils can be improved. (Kamimura, M.)

  20. Coil winding pack FE-analysis for a HELIAS reactor

    International Nuclear Information System (INIS)

    Schauer, F.; Egorov, K.; Bykov, V.

    2011-01-01

    At the Max-Planck-Institut fuer Plasmaphysik (IPP) a reference design is being created of an upgraded five-periodic HELIAS type stellarator reactor which evolves from Wendelstein 7-X (W7-X) by scaling of the coil centre line geometries by a factor of four. This reactor type was extensively investigated at IPP with regard to physical characteristics and to some extent also to engineering issues. The upgrade concerns an increase of the induction at the plasma axis and correspondingly at the superconductor. The aim is to develop the reactor concept to a stage and such detail that major engineering problems are unveiled, and relevant comparisons with other concepts, including tokamaks, can be drawn in view of upcoming decisions concerning a DEMO reactor. Even though progress in plasma physics, and in particular future results of W7-X and other machines - particularly of ITER - will probably lead to somewhat different coil shapes, no principal changes of the reference design are expected. In this paper the option of a roll-formed square coil cable jacket is investigated. Detailed structural FE analysis of the coil winding pack demonstrates the feasibility of such a conductor which appears to be the most economical option. It also allows sufficient space for a cable current density very similar to that of the ITER TF coil with a similar overall winding pack cross section of ∼0.5 m 2 . Already existing Nb 3 Sn conductors could thus be safely applied in such a HELIAS reactor. Obvious progress of superconductor technology, particularly concerning Nb 3 Al, will be beneficial concerning savings of conductor material, ease of manufacture, higher operation temperature, etc.

  1. Superconducting magnet

    Science.gov (United States)

    1985-01-01

    Extensive computer based engineering design effort resulted in optimization of a superconducting magnet design with an average bulk current density of approximately 12KA/cm(2). Twisted, stranded 0.0045 inch diameter NbTi superconductor in a copper matrix was selected. Winding the coil from this bundle facilitated uniform winding of the small diameter wire. Test coils were wound using a first lot of the wire. The actual packing density was measured from these. Interwinding voltage break down tests on the test coils indicated the need for adjustment of the wire insulation on the lot of wire subsequently ordered for construction of the delivered superconducting magnet. Using the actual packing densities from the test coils, a final magnet design, with the required enhancement and field profile, was generated. All mechanical and thermal design parameters were then also fixed. The superconducting magnet was then fabricated and tested. The first test was made with the magnet immersed in liquid helium at 4.2K. The second test was conducted at 2K in vacuum. In the latter test, the magnet was conduction cooled from the mounting flange end.

  2. Design and modelling of a SMES coil

    Energy Technology Data Exchange (ETDEWEB)

    Yuan Weijia; Campbell, A M; Coombs, T A, E-mail: wy215@cam.ac.u [EPEC Superconductivity group, Engineering Department, 9 JJ Thomson Avenue, Cambridge, CB3 0FA (United Kingdom)

    2010-06-01

    The design of a Superconducting Magnetic Energy Storage (SMES) coil wound by coated conductors has been presented. Based on an existing model for coated conductor pancake coils, this paper analysed the magnetic field and current density distribution of the coil at two different operation temperatures, 77K and 22K. A comparison table of the critical currents and AC losses at these two temperatures has been presented. Several steps to improve the transport current of the coil have been suggested as well.

  3. Superconducting magnet and cryostat for a space application

    Science.gov (United States)

    Pope, W. L.; Smoot, G. F.; Smith, L. H.; Taylor, C. E.

    1975-01-01

    The paper describes the design concepts, development, and testing of a superconducting coil and cryostat for an orbiting superconducting magnetic spectrometer. Several coils were subject to overall thermal performance and coil charging tests. The coils have low but persistent currents and have proven themselves to be rugged and reliable for mobile balloon flights. Satellite experiments will be conducted on a new, similar design.

  4. Large coil program support structure conceptual design

    International Nuclear Information System (INIS)

    Litherland, P.S.

    1977-01-01

    The purpose of the Large Coil Program (LCP) is to perform tests on both pool boiling and force cooled superconducting toroidal field coils. The tests will attempt to approximate conditions anticipated in an ignition tokamak. The test requirements resulted in a coil support design which accommodates up to six (6) test coils and is mounted to a structure capable of resisting coil interactions. The steps leading to the present LCP coil support structure design, details on selected structural components, and the basic assembly sequence are discussed

  5. Electromagnetic design of superconducting quadrupoles

    Directory of Open Access Journals (Sweden)

    L. Rossi

    2006-10-01

    Full Text Available We study how the critical gradient depends on the coil layout in a superconducting quadrupole for particle accelerators. We show that the results relative to a simple sector coil are well representative of the coil layouts that have been used to build several quadrupoles in the past 30 years. Using a semianalytical approach, we derive a formula that gives the critical gradient as a function of the coil cross-sectional area, of the magnet aperture, and of the superconducting cable parameters. This formula is used to evaluate the efficiency of several types of coil layouts (shell, racetrack, block, open midplane.

  6. Superconducting magnet development in Japan

    International Nuclear Information System (INIS)

    Yasukochi, K.

    1983-01-01

    The present state of R and D works on the superconducting magnet and its applications in Japan are presented. On electrical rotating machines, 30 MVA superconducting synchronous rotary condenser (Mitsubishi and Fuji) and 50 MVA generator are under construction. Two ways of ship propulsion by superconducting magnets are developing. A superconducting magnetically levitated and linear motor propelled train ''MAGLEV'' was developed by the Japan National Railways (JNR). The superconducting magnet development for fusion is the most active field in Japan. The Cluster Test program has been demonstrated on a 10 T Nb 3 Sn coil and the first coil of Large Coil Task in IEA collaboration has been constructed and the domestic test was completed in JAERI. These works are for the development of toroidal coils of the next generation tokamak machine. R and D works on superconducting ohmic heating coil are in progress in JAERI and ETL. The latter group has constructed 3.8 MJ pulsed coil. A high ramp rate of changing field in pulsed magnet, 200 T/s, has been tested successfully. High Energy Physics Laboratory (KEK) are conducting active works. The superconducting μ meson channel and π meson channel have been constructed and are operating successfully. KEK has also a project of big accelerator named ''TRISTAN'', which is similar to ISABELLE project of BNL. Superconducting synchrotron magnets are developed for this project. The development of superconducting three thin wall solenoid has been started. One of them, CDF, is progressing under USA-Japan collaboration

  7. Superconducting energy storage magnet

    International Nuclear Information System (INIS)

    Eyssa, Y.M.; Boom, R.W.; Young, W.C.; McIntosh, G.E.; Abdelsalam, M.K.

    1986-01-01

    A superconducting magnet is described comprising: (a) a first, outer coil of one layer of conductor including at least a superconducting composite material; (b) a second, inner coil of one layer of conductor including at least a superconducting composite material. The second coil disposed adjacent to the first coil with each turn of the second inner coil at substantially the same level as a turn on the first coil; (c) an inner support structure between the first and second coils and engaged to the conductors thereof, including support rails associated with each turn of conductor in each coil and in contact therewith along its length at positions on the inwardly facing periphery of the conductor. The rail associated with each conductor is electrically isolated from other rails in the inner support structure. The magnetic field produced by a current flowing in the same direction through the conductors of the first and second coils produces a force on the conductors that are directed inwardly toward the inner support structure

  8. CERN News: Selection of the type of superconducting coil for the Omega project; New intensity records at the proton synchrotron; Progress with the Spiral Reader film measuring equipment; New technique at transition energy on the proton synchrotron; CERN Courier 10th anniversary; Equipment travelling from and to Serpukhov

    CERN Multimedia

    1969-01-01

    CERN News: Selection of the type of superconducting coil for the Omega project; New intensity records at the proton synchrotron; Progress with the Spiral Reader film measuring equipment; New technique at transition energy on the proton synchrotron; CERN Courier 10th anniversary; Equipment travelling from and to Serpukhov

  9. Critical current density and flux pinning in superconducting wires and coils of silver-clad Bi-Pb-Sr-Ca-Cu-O

    International Nuclear Information System (INIS)

    Dou, S.X.; Liu, H.K.; Apperley, M.H.; Song, K.H.; Sorrell, C.C.; Guo, S.J.; Loberg, B.; Easterling, K.E.

    1991-01-01

    The critical current density (J c ) of Ag-clad of Bi-Pb-Sr-Ca-Cu-O has been measured to be about 12,000 A/cm 2 at 77 K in zero field. This wire was rolled into a tape of thickness 0.1 mm and width of 2 to 3 mm, and a coil of 35 mm diameter was formed. The J c of this coil was measured to be about 2,000 A/cm 2 at 77 K over the full length (1.00 meter) of the coil. In this paper compositions, heat treatment parameters, and cold-deformation for enhancement of J c are presented. The microstructure is characterized and pinning interactions as well as possible weak links are emphasised. (orig.)

  10. The IEA Large Coil Task

    International Nuclear Information System (INIS)

    Beard, D.S.; Klose, W.; Shimamoto, S.; Vecsey, G.

    1988-01-01

    A multinational program of cooperative research, development, demonstrations, and exchanges of information on superconducting magnets for fusion was initiated in 1977 under an IEA agreement. The first major step in the development of TF magnets was called the Large Coil Task. Participants in LCT were the U.S. DOE, EURATOM, JAERI, and the Departement Federal de l'Interieur of Switzerland. The goals of LCT were to obtain experimental data, to demonstrate reliable operation of large superconducting coils, and to prove design principles and fabrication techniques being considered for the toroidal magnets of thermonuclear reactors. These goals were to be accomplished through coordinated but largely independent design, development, and construction of six test coils, followed by collaborative testing in a compact toroidal test array at fields of 8 T and higher. Under the terms of the IEA Agreement, the United States built and operated the test facility at Oak Ridge and provided three test coils. The other participants provided one coil each. Information on design and manufacturing and all test data were shared by all. The LCT team of each participant included a government laboratory and industrial partners or contractors. The last coil was completed in 1985, and the test assembly was completed in October of that year. Over the next 23 months, the six-coil array was cooled down and extensive testing was performed. Results were gratifying, as tests achieved design-point performance and well beyond. (Each coil reached a peak field of 9 T.) Experiments elucidated coil behavior, delineated limits of operability, and demonstrated coil safety. (orig./KP)

  11. Superconductivity in power engineering

    International Nuclear Information System (INIS)

    1989-01-01

    This proceedings volume presents 24 conference papers and 15 posters dealing with the following aspects: 1) Principles and elementary aspects of high-temperature superconductivity (3 plenary lectures); 2) Preparation, properties and materials requirements of metallic or oxide superconductors (critical current behaviour, soldered joints, structural studies); 3) Magnet technology (large magnets for thermonuclear fusion devices; magnets for particle accelerators and medical devices); 4) Magnetic levitation and superconductivity; 5) Cryogenics; 6) Energy storage systems using superconducting coils (SMES); 7) Superconducting power transmission cables, switches, transformers, and generator systems for power plant; 8) Supporting activities, industrial aspects, patents. There are thirty-eight records in the ENERGY database relating to individual conference papers. (MM) [de

  12. Calculation of alternating current losses in stacks and coils made of second generation high temperature superconducting tapes for large scale applications

    DEFF Research Database (Denmark)

    Zermeno, Victor M. R.; Abrahamsen, Asger Bech; Mijatovic, Nenad

    2013-01-01

    A homogenization method to model a stack of second generation High Temperature Superconducting tapes under AC applied transport current or magnetic field has been obtained. The idea is to find an anisotropic bulk equivalent for the stack such that the geometrical layout of the internal alternatin...

  13. Overview video diagnostics for the W7-X stellarator

    Energy Technology Data Exchange (ETDEWEB)

    Kocsis, G., E-mail: kocsis.gabor@wigner.mta.hu [Wigner RCP, RMI, Konkoly Thege 29-33, H-1121 Budapest (Hungary); Baross, T. [Wigner RCP, RMI, Konkoly Thege 29-33, H-1121 Budapest (Hungary); Biedermann, C. [Max-Planck-Institute for Plasma Physics, 17491 Greifswald (Germany); Bodnár, G.; Cseh, G.; Ilkei, T. [Wigner RCP, RMI, Konkoly Thege 29-33, H-1121 Budapest (Hungary); König, R.; Otte, M. [Max-Planck-Institute for Plasma Physics, 17491 Greifswald (Germany); Szabolics, T.; Szepesi, T.; Zoletnik, S. [Wigner RCP, RMI, Konkoly Thege 29-33, H-1121 Budapest (Hungary)

    2015-10-15

    Considering the requirements of the newly built Wendelstein 7-X stellarator a ten-channel overview video diagnostic system was developed and is presently under installation. The system covering the whole torus interior can be used not only to observe the plasma but also to detect irregular operational events which are dangerous for the stellarator itself and to send automatic warning for the machine safety. The ten tangential AEQ ports used by the diagnostic remain under atmospheric pressure, the vacuum/air interface is at the front window located at the plasma side of the AEQ port. The optical vacuum window is protected by a cooled pinhole. The Sensor Module (SM) of the intelligent camera (EDICAM) – developed especially for this purpose – is located directly behind the vacuum window. EDICAM is designed to simultaneously record several regions of interest of its CMOS sensor with different frame rate and to detect various predefined events in real time. The air cooled SM is fixed by a docking mechanism which can preserve the pointing of the view. EDICAM can withstand the magnetic field (∼3 T), the neutron and gamma fluxes expected in the AEQ port. In order to adopt the new features of the video diagnostics system both control and data acquisition and visualization and data processing softwares are developed.

  14. Overview video diagnostics for the W7-X stellarator

    International Nuclear Information System (INIS)

    Kocsis, G.; Baross, T.; Biedermann, C.; Bodnár, G.; Cseh, G.; Ilkei, T.; König, R.; Otte, M.; Szabolics, T.; Szepesi, T.; Zoletnik, S.

    2015-01-01

    Considering the requirements of the newly built Wendelstein 7-X stellarator a ten-channel overview video diagnostic system was developed and is presently under installation. The system covering the whole torus interior can be used not only to observe the plasma but also to detect irregular operational events which are dangerous for the stellarator itself and to send automatic warning for the machine safety. The ten tangential AEQ ports used by the diagnostic remain under atmospheric pressure, the vacuum/air interface is at the front window located at the plasma side of the AEQ port. The optical vacuum window is protected by a cooled pinhole. The Sensor Module (SM) of the intelligent camera (EDICAM) – developed especially for this purpose – is located directly behind the vacuum window. EDICAM is designed to simultaneously record several regions of interest of its CMOS sensor with different frame rate and to detect various predefined events in real time. The air cooled SM is fixed by a docking mechanism which can preserve the pointing of the view. EDICAM can withstand the magnetic field (∼3 T), the neutron and gamma fluxes expected in the AEQ port. In order to adopt the new features of the video diagnostics system both control and data acquisition and visualization and data processing softwares are developed.

  15. Test results for a Bi-2223 HTS racetrack coil for generator applications

    International Nuclear Information System (INIS)

    Salasoo, L.; Herd, K.G.; Laskaris, E.T.; Hart, H.R. Jr.; Chari, M.V.K.

    1996-01-01

    Testing, results and analysis of a Bi-2223 model superconducting generator coil produced under the DOE Superconductivity Partnership Initiative are presented. The test arrangement enables coil energization with dc and transient currents over a range of operating temperatures to explore coil performance under conditions analogous to those that would be experienced by a superconducting generator field coil. Analytical calculations of coil ac and ohmic losses and temperature rise compare well with experimental measurements. Good performance is predicted for a typical 3-phase fault condition. Coil steady state and transient performance can be predicted with confidence for full scale superconductor application

  16. Large Coil Program magnetic system design study

    International Nuclear Information System (INIS)

    Moses, S.D.; Johnson, N.E.

    1977-01-01

    The primary objective of the Large Coil Program (LCP) is to demonstrate the reliable operation of large superconducting coils to provide a basis for the design principles, materials, and fabrication techniques proposed for the toroidal magnets for the THE NEXT STEP (TNS) and other future tokamak devices. This paper documents a design study of the Large Coil Test Facility (LCTF) in which the structural response of the Toroidal Field (TF) Coils and the supporting structure was evaluated under simulated reactor conditions. The LCP test facility structural system consists of six TF Coils, twelve coil-to-coil torsional restraining beams (torque rings), a central bucking post with base, and a Pulse Coil system. The NASTRAN Finite Element Structural Analysis computer Code was utilized to determine the distribution of deflections, forces, and stresses for each of the TF Coils, torque rings, and the central bucking post. Eleven load conditions were selected to represent probable test operations. Pulse Coils suspended in the bore of the test coil were energized to simulate the pulsed field environment characteristic of the TNS reactor system. The TORMAC Computer Code was utilized to develop the magnetic forces in the TF Coils for each of the eleven loading conditions examined, with or without the Pulse Coils energized. The TORMAC computer program output forces were used directly as input load conditions for the NASTRAN analyses. Results are presented which demonstrate the reliability of the LCTF under simulated reactor operating conditions

  17. Insulating process for HT-7U central solenoid model coils

    International Nuclear Information System (INIS)

    Cui Yimin; Pan Wanjiang; Wu Songtao; Wan Yuanxi

    2003-01-01

    The HT-7U superconducting Tokamak is a whole superconducting magnetically confined fusion device. The insulating system of its central solenoid coils is critical to its properties. In this paper the forming of the insulating system and the vacuum-pressure-impregnating (VPI) are introduced, and the whole insulating process is verified under the super-conducting experiment condition

  18. Superconducting accelerator magnet design

    International Nuclear Information System (INIS)

    Wolff, S.

    1994-01-01

    Superconducting dipoles, quadrupoles and correction magnets are necessary to achieve the high magnetic fields required for big accelerators presently in construction or in the design phase. Different designs of superconducting accelerator magnets are described and the designs chosen at the big accelerator laboratories are presented. The most frequently used cosθ coil configuration is discussed in detail. Approaches for calculating the magnetic field quality including coil end fields are presented. Design details of the cables, coils, mechanical structures, yokes, helium vessels and cryostats including thermal radiation shields and support structures used in superconducting magnets are given. Necessary material properties are mentioned. Finally, the main results of magnetic field measurements and quench statistics are presented. (orig.)

  19. Remote maintenance of tandem mirror hybrid coils

    International Nuclear Information System (INIS)

    Dietz, L.P.

    1983-01-01

    Hybrid Coils (superconducting coils with normal conducting inserts) are being employed with increasing frequency on Tandem Mirror Devices to obtain high field strengths. The normal conducting copper inserts are short lived in comparison to their encircling superconductors. It becomes desirable, therefore, to devise design features and maintenance procedures to replace the inner normal conducting coils without simultaneously replacing the longer lived (and significantly more costly) superconducting coils. The high neutron wall loadings require that the task be accomplished by remote control. The approach is to permanently mount the coil assemblies on track mounted carriages which serve, during machine operation merely as structural supports, but during maintenance procedures as moveable transport devices. The carriages incorporate all necessary provisions to facilitate remote maintenance operations and to adjust and align the coil assemblies with respect to adjacent machine components. The vacuum vessel is severed on both sides of the hybrid coil by means of a remote cutting machine. The entire coil is transported horizontally, normal to the machine axis to a nearby repair station. Prepositioned carriage mounted repair equipment at the repair station withdraws the damaged normal coil as a single entity and inserts a preassembled spare unit. The repaired hybrid coil is reassembled to the reactor. A cost and risk effective procedure has been evolved to maintain one of the more critical components of a Tandem Mirror Machine

  20. Testing electrical insulation of LCT coils and instrumentation

    International Nuclear Information System (INIS)

    Luton, J.N.; Ulbricht, A.R.; Ellis, J.F.; Shen, S.S.; Wilson, C.T.; Okuno, K.; Siewerdt, L.O.; Zahn, G.R.; Zichy, J.A.

    1986-09-01

    Three of the superconducting test coils in the Large Coil Task (LCT) use conductors cooled internally by forced flow of helium. In the other three coils, the conductors are cooled externally by a bath of helium. The coils and facility are designed for rapid discharges (dumps) at voltages up to 2.5 kV, depending on coil design. Many coil sensors are connected electrically to the conductors. These sensor leads and signal conditioning equipment also experience high voltage. High-potential tests of ground insulation were performed on all components of the International Fusion Superconducting Magnet Test Facility (IFSMTF). Coil insulation was also tested by ring-down tests that produced voltage distributions within the coils like those occurring during rapid discharge. Methods were developed to localize problem areas and to eliminate them. The effect on breakdown voltage near the Paschen minimum of magnetic fields up to 2 T was investigated

  1. Superconducting magnets and leads thereto

    International Nuclear Information System (INIS)

    Biltcliffe, M.N.; Hanley, P.E.; McKinnon, J.B.; Wheatley, R.W.

    1975-01-01

    The magnet described comprises a cryostat containing a superconducting coil for the generation of a magnetic field, with a short-circuiting superconducting link connected across the coil, and electrical leads extending through the cryostat to the coil; these leads are provided with joints within the cryostat to enable them to be detached from the coil and removed from the cryostat without interrupting the current through the coil, thus reducing heat conduction to the cryostat through the leads. The joints are arranged so that the leads can be readily detached and re-attached to the coil from outside the cryostat. Gas-tight seals are provided where the leads pass through the outer wall of the cryostat, with caps that can be secured after removal of the leads. This kind of magnet can provide a stable magnetic field continuously over long periods, such as is required in nuclear magnetic resonance spectrometers. (U.K.)

  2. Program for development of toroidal superconducting magnets for fusion research

    International Nuclear Information System (INIS)

    Long, H.M.; Lubell, M.S.

    1976-04-01

    Research progress on the following subprograms is described/: (1) system design, (2) coil design, (3) conductor selection and test, (4) radiation effects on superconducting coils, (5) coil protection, eddy current shielding, and power supply, (6) structural analysis and materials investigation, (7) cryogenics and refrigeration, (8) subsize coil fabrication, (9) large coil project, (10) coil testing and evaluation, (11) administrative plan, and (12) quality assurance and reliability

  3. Development of manufacturing technology of radial plate in superconducting coil for fusion reactor by diffusion bonding by Hot Isostatic Pressing (HIP)

    International Nuclear Information System (INIS)

    Takano, Katsutoshi; Koizumi, Norikiyo; Masuo, Hiroshi; Natsume, Yoshihisa

    2014-01-01

    The radial plates (RPs), which is used in Toroidal field (TF) coil in ITER, are quite large, such as 13 m tall and 9 m wide, but thin, such as 10 cm thick, and are made of stainless steel. Even though they are very large structures, they require very high manufacturing tolerances and high mechanical strength at 4 K. The similar requirements will be required in the next generation fusion reactor. Therefore, the authors intend to develop efficient manufacturing methods in parallel with ITER TF coil RP manufacture. The authors therefore performed trial manufacture of the RP segments using a diffusion bonding method, namely Hot Isostatic Pressing (HIP). As a result of trials, it was clarified that even when HIPping is applied, the mechanical characteristic of base metal is not deteriorated. The machining period can be reduced by about 1/3 compared with the traditional manufacturing method. On the other hand, mechanical strength at 4 K is degraded due to weak bonding, that is no grain growth through joint, by HIPping. However, additional test indicates promising possibility of much better joint by higher temperature and joint surface treated HIPpings. These results justified that RP segment manufacturing is not only possible, but it is a technically valid manufacturing method that satisfies all requirements. (author)

  4. Complete Fabrication of a Traversable 3 µm Thick NbN Film Superconducting Coil with Cu plated layer of 42m in Length in a Spiral Three-Storied Trench Engraved in a Si Wafer of 76.2 mm in Diameter Formed by MEMS Technology for a Compact SMES with High Energy Storage Volume Density

    Science.gov (United States)

    Suzuki, Yasuhiro; Iguchi, Nobuhiro; Adachi, Kazuhiro; Ichiki, Akihisa; Hioki, Tatsumi; Hsu, Che-Wei; Sato, Ryoto; Kumagai, Shinya; Sasaki, Minoru; Noh, Joo-Hyong; Sakurahara, Yuuske; Okabe, Kyohei; Takai, Osamu; Honma, Hideo; Watanabe, Hideo; Sakoda, Hitoshi; Sasagawa, Hiroaki; Doy, Hideyuki; Zhou, Shuliang; Hori, H.; Nishikawa, Shigeaki; Nozaki, Toshihiro; Sugimoto, Noriaki; Motohiro, Tomoyoshi

    2017-09-01

    Based on the concept of a novel approach to make a compact SMES unit composed of a stack of Si wafers using MEMS process proposed previously, a complete fabrication of a traversable 3 µam thick NbN film superconducting coil lined with Cu plated layer of 42m in length in a spiral three-storied trench engraved in and extended over a whole Si-wafer of 76.2 mm in diameter was attained for the first time. With decrease in temperature, the DC resistivity showed a metallic decrease indicating the current pass was in the Cu plated layer and then made a sudden fall to residual contact resistance indicating the shift of current pass from the Cu plated layer to the NbN film at the critical temperature Tc of 15.5K by superconducting transition. The temperature dependence of I-V curve showed the increase in the critical current with decrease in the temperature and the highest critical current measured was 220 mA at 4K which is five times as large as that obtained in the test fabrication as the experimental proof of concept presented in the previous report. This completion of a one wafer superconducting NbN coil is an indispensable step for the next proof of concept of fabrication of series-connected two wafer coils via superconductive joint which will read to series connected 600 wafer coils finally, and for replacement of NbN by high Tc superconductor such as YBa2Cu3O7-x for operation under the cold energy of liquid hydrogen or liquid nitrogen.

  5. Resistive demountable toroidal-field coils for tokamak reactors

    International Nuclear Information System (INIS)

    Jassby, D.L.; Jacobsen, R.A.; Kalnavarns, J.; Masson, L.S.; Sekot, J.P.

    1981-07-01

    Readily demountable TF (toroidal-field) coils allow complete access to the internal components of a tokamak reactor for maintenance of replacement. The requirement of readily demountable joints dictates the use of water-cooled resistive coils, which have a host of decisive advantages over superconducting coils. Previous papers have shown that resistive TF coils for tokamak reactors can operate in the steady state with acceptable power dissipation (typically, 175 to 300 MW). This paper summarizes results of parametric studies of size optimization of rectangular TF coils and of a finite-element stress analysis, and examines several candidate methods of implementing demountable joints for rectangular coils constructed of plate segments

  6. ORPUS 1: a pulsed superconducting solenoid

    International Nuclear Information System (INIS)

    Schwall, R.E.

    1976-01-01

    A recent series of reference designs for Tokamak Experimental Power Reactors (EPR's) has indicated that superconducting poloidal field (PF) coils will be necessary for successful operation of these devices. It would also be desirable to use superconducting PF coils in earlier tokamak fusion devices if such coils could be developed quickly enough. The PF coil performance requirements are briefly reviewed and some implications for the coil design are developed. A small coil (stored energy 14 kJ) has been built using construction techniques similar to those which could be employed for PF coils. The coil has been charged at rates up to 2 T/sec. Both maximum field and charging rate were limited by available power supplies. Loss measurements were carried out during pulsed operation and data for hysteretic and eddy current loss are presented. The loss measurement system used allows considerable insight into the effects of conductor motion and training

  7. Potential damage to dc superconducting magnets due to high frequency electromagnetic waves

    Science.gov (United States)

    Gabriel, G. J.; Burkhart, J. A.

    1977-01-01

    Studies of a d.c. superconducting magnet coil indicate that the large coil behaves as a straight waveguide structure. Voltages between layers within the coil sometimes exceeded those recorded at terminals where protective resistors are located. Protection of magnet coils against these excessive voltages could be accomplished by impedance matching throughout the coil system. The wave phenomenon associated with superconducting magnetic coils may create an instability capable of converting the energy of a quiescent d.c. superconducting coil into dissipative a.c. energy, even in cases when dielectric breakdown does not take place.

  8. Power loss problems in EXTRAP coil systems

    International Nuclear Information System (INIS)

    Lehnert, B.

    1977-02-01

    The Ohmic power loss in the coils of external ring traps is minimized with respect to the thermonuclear power production. In the case of the DT-reaction this leads to dimensions and power densities being relevant to full-scale reactors. Not only superconducting or refrigerated coil windings can thus be used, but also hot-coil systems which are operated at several hundred degrees centrigrade and form part of a steam cycle and power extraction system. For hot coils the problems of void formation and tritium regeneration have to be further examined. The high beta value leads to moderately large coil stresses. Finally, replacement and repair become simplified by the present coil geometry. (Auth.)

  9. Checking BEBC superconducting magnet

    CERN Multimedia

    CERN PhotoLab

    1974-01-01

    The superconducting coils of the magnet for the 3.7 m Big European Bubble Chamber (BEBC) had to be checked, see Annual Report 1974, p. 60. The photo shows a dismantled pancake. By December 1974 the magnet reached again the field design value of 3.5 T.

  10. Electrical Conduction and Superconductivity

    Indian Academy of Sciences (India)

    When an electric field is applied, this electron can be lifted to this higher energy ... By such a virtual process two electrons .... using superconducting coils has come to be a reality. ... nance imaging techniques used in medical diagnostics. Com ...

  11. 12 tesla test coil. Annual progress report

    International Nuclear Information System (INIS)

    1979-01-01

    The Plasma Fusion Center at MIT has been charged with responsibility for the design, development, fabrication and test operation of a Niobium-3-Tin Superconducting Test Coil. Research is described on DOE's 12 tesla coil demonstration program in which several one-meter diameter superconducting test coils will be inserted and tested in DOE's High Field Test Facility at the Lawrence Livermore Laboratories. The work was initiated at the start of FY 79. FY 79 saw the completion of our Preliminary Design and the initiation of three (3) subcontracts: (1) Westinghouse review of the Preliminary Design, (II) Supercon, Inc. development of a tubular copper matrix, Nb 3 Sn Superconductor and (III) Airco optimization of the LCP-W Nb 3 Sn superconductor for 12T service. In addition, Airco was charged with the production of a 1000 foot length of model 15,000A conductor. Coil winding exercises were initiated at the Everson Electric Company

  12. The SMES model coil. Fabrication

    International Nuclear Information System (INIS)

    Hanai, Satoshi; Nakamoto, Kazunari; Takahashi, Nobuji

    1998-01-01

    A SMES model coil was fabricated as R and D item in the development of component technologies for a 480 MJ/20 MW SMES pilot plant. The coil consists of four double-pancake windings. The coil is the same diameter but half the number of pancakes that will be needed for a SMES pilot plant. The NbTi cable-in-conduit conductor and superconducting joints between the double pancakes are cooled by a forced flow of supercritical helium. Prior to fabrication, various characteristics of the cable-in-conduit were measured by full-sized short samples from actual conductors and by scaled short samples from scaled conductors. The critical current of the scaled short samples was in agreement with that calculated from one strand of the conductor. The impedance between arbitrary dual-oxide coated strands in the full-size conductor was measured to be smaller than that obtained from two Cr-plated strands, which showed a good degree of stability in another coil. It was estimated that oxide-coated conductors would have high stability. Through fabrication of a model coil, it was demonstrated that a large forced-flow coil for a small-scale 100 kWh SMES device could be manufactured. (author)

  13. The SMES model coil. Fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Hanai, Satoshi; Nakamoto, Kazunari; Takahashi, Nobuji [Toshiba Corp., Yokohama, Kanagawa (Japan)] [and others

    1998-07-01

    A SMES model coil was fabricated as R and D item in the development of component technologies for a 480 MJ/20 MW SMES pilot plant. The coil consists of four double-pancake windings. The coil is the same diameter but half the number of pancakes that will be needed for a SMES pilot plant. The NbTi cable-in-conduit conductor and superconducting joints between the double pancakes are cooled by a forced flow of supercritical helium. Prior to fabrication, various characteristics of the cable-in-conduit were measured by full-sized short samples from actual conductors and by scaled short samples from scaled conductors. The critical current of the scaled short samples was in agreement with that calculated from one strand of the conductor. The impedance between arbitrary dual-oxide coated strands in the full-size conductor was measured to be smaller than that obtained from two Cr-plated strands, which showed a good degree of stability in another coil. It was estimated that oxide-coated conductors would have high stability. Through fabrication of a model coil, it was demonstrated that a large forced-flow coil for a small-scale 100 kWh SMES device could be manufactured. (author)

  14. Critical current studies of a HTS rectangular coil

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Z. [Department of Engineering, University of Cambridge (United Kingdom); Chudy, M., E-mail: Michal.chudy@stuba.sk [Graduate School of Technology Management, University of Pretoria (South Africa); Institute of Power and Applied Electrical Engineering, Slovak University of Technology in Bratislava (Slovakia); Ruiz, H.S. [Department of Engineering, University of Leicester, Leicester LE1 7RH (United Kingdom); Zhang, X.; Coombs, T. [Department of Engineering, University of Cambridge (United Kingdom)

    2017-05-15

    Highlights: • Unique square pancake coil was manufactured. • Measurements in relatively high magnetic field were performed. • Different sections of the coil were characterized. • Parts of the coil which are limiting critical current were identified. - Abstract: Nowadays, superconducting high field magnets are used in numerous applications due to their superior properties. High temperature superconductors (HTS) are usually used for production of circular pancake or racetrack coils. However different geometries of HTS coils might be required for some specific applications. In this study, the HTS coil wound on a rectangular frame was fully characterized in homogeneous DC background field. The study contains measurements of critical current angular dependencies. The critical current of the entire coil and two selected strands under different magnitudes and orientations of external magnetic fields are measured. The critical regions of the coil in different angular regimes are determined. This study brings better understanding of the in- field performance of HTS coils wound on frames with right-angles.

  15. Design of the coolant system for the Large Coil Test Facility pulse coils

    International Nuclear Information System (INIS)

    Bridgman, C.; Ryan, T.L.

    1983-01-01

    The pulse coils will be a part of the Large Coil Test Facility in Oak Ridge, Tennessee, which is designed to test six large tokamak-type superconducting coils. The pulse coil set consists of two resistive coaxial solenoid coils, mounted so that their magnetic axis is perpendicular to the toroidal field lines of the test coil. The pulse coils provide transient vertical fields at test coil locations to simulate the pulsed vertical fields present in tokamak devices. The pulse coils are designed to be pulsed for 30 s every 150 s, which results in a Joule heating of 116 kW per coil. In order to provide this capability, the pulse coil coolant system is required to deliver 6.3 L/s (100 gpm) of subcooled liquid nitrogen at 10-atm absolute pressure. The coolant system can also cool down each pulse coil from room temperature to liquid nitrogen temperature. This paper provides details of the pumping and heat exchange equipment designed for the coolant system and of the associated instrumentation and controls

  16. Preliminary study on AC superconducting machines

    International Nuclear Information System (INIS)

    Yamamoto, M.; Ishigohka, T.; Shimohka, T.; Mizukami, N.; Yamaguchi, M.

    1988-01-01

    This paper describes the issues involved in developing AC superconducting machines. In the first phase, as a preliminary experiment, a 4kVa AC superconducting coil which employs 100A class 50/60Hz superconductors is made and tested. And, in the second phase, as an extension of the 4kVa coil, a model superconducting transformer is made and examined. The transformer has a novel quench protection system with an auxiliary coil only in the low voltage side. The behavior of the overcurrent protection system is confirmed

  17. Dual levitated coils for antihydrogen production

    Science.gov (United States)

    Wofford, J. D.; Ordonez, C. A.

    2013-04-01

    Two coaxial superconducting magnetic coils that carry currents in the same direction and that are simultaneously levitated may serve for antihydrogen plasma confinement. The configuration may be suitable for use by a collaboration at the CERN Antiproton Decelerator facility to test fundamental symmetries between the properties of hydrogen and antihydrogen. Nested Penning traps are currently used to confine recombining antihydrogen plasma. Symmetry studies require the production of sufficiently cold antihydrogen. However, plasma drifts within nested Penning traps can increase the kinetic energy of antiprotons that form antihydrogen atoms. Dual levitated coils may serve to confine relatively large, cold, dense non-drifting recombining antihydrogen plasmas. A minimum-B magnetic field that is produced by the coils could provide for atom trapping. A toroidal plasma is confined between the coils. High density plasmas may be possible, by allowing plasma pressure to balance mechanical pressure to keep the coils apart. Progress is reported on theoretical and experimental efforts. The theoretical effort includes the development of a classical trajectory Monte Carlo simulation of confinement. The experimental effort includes levitation of a NdFeB permanent ring magnet, which produces a magnetic field that is qualitatively similar to the field that would be produced by the two coaxial superconducting magnetic coils. Liquid-nitrogen-cooled Bi-2223 high-temperature-superconducting components, with a critical temperature of 108 K, were used to levitate the ring magnet. An issue concerning keeping the plane of the levitated ring horizontal is discussed.

  18. Superconducting magnetic energy storage apparatus structural support system

    Science.gov (United States)

    Withers, Gregory J.; Meier, Stephen W.; Walter, Robert J.; Child, Michael D.; DeGraaf, Douglas W.

    1992-01-01

    A superconducting magnetic energy storage apparatus comprising a cylindrical superconducting coil; a cylindrical coil containment vessel enclosing the coil and adapted to hold a liquid, such as liquefied helium; and a cylindrical vacuum vessel enclosing the coil containment vessel and located in a restraining structure having inner and outer circumferential walls and a floor; the apparatus being provided with horizontal compression members between (1) the coil and the coil containment vessel and (2) between the coil containment vessel and the vacuum vessel, compression bearing members between the vacuum vessel and the restraining structure inner and outer walls, vertical support members (1) between the coil bottom and the coil containment vessel bottom and (2) between the coil containment vessel bottom and the vacuum vessel bottom, and external supports between the vacuum vessel bottom and the restraining structure floor, whereby the loads developed by thermal and magnetic energy changes in the apparatus can be accommodated and the structural integrity of the apparatus be maintained.

  19. Preliminary results of the US pool-boiling coils from the IFSMTF full-array tests

    International Nuclear Information System (INIS)

    Lue, J.W.; Dresner, L.; Lubell, M.S.; Luton, J.N.; McManamy, T.J.; Shen, S.S.

    1986-01-01

    The Large Coil Task to develop superconducting magnets for fusion reactors, is now in the midst of full-array tests in the International Fusion Superconducting Magnet Test Facility at Oak Ridge National Laboratory. Included in the test array are two pool-boiling coils designed and fabricated by US manufacturers, General Dynamics/Convair Division and General Electric/Union Carbide Corporation. So far, both coils have been energized to full design currents in the single-coil tests, and the General Dynamics coil has reached the design point in the first Standard-I full-array test. Both coils performed well in the charging experiments. Extensive heating tests and the heavy instrumentation of these coils have, however, revealed some generic limitations of large pool-boiling superconducting coils. Details of these results and their analyses are reported

  20. The development of superconducting equipment

    CERN Document Server

    Ueda, T; Hiue, H

    2003-01-01

    Fuji Electric has been developing various types of superconducting equipment for over a quarter of a century. This paper describes the development results achieved for superconducting equipment and especially focuses on large-capacity current leads and superconducting transmission systems, the development of which is being promoted for application to the field of nuclear fusion. High temperature superconductor (HTS) is becoming the mainstream in the field of superconductivity, and the HTS floating coil and conduction-cooled HTS transformed are also introduced as recent developments for devices that utilize this technology. (author)

  1. CS model coil experimental log book

    International Nuclear Information System (INIS)

    Nishijima, Gen; Sugimoto, Makoto; Nunoya, Yoshihiko; Wakabayashi, Hiroshi; Tsuji, Hiroshi

    2001-02-01

    Charging test of the ITER CS Model Coil which is the world's largest superconducting pulse coil and the CS Insert Coil had started at April 11, 2000 and had completed at August 18, 2000. In the campaign, total shot numbers were 356 and the size of the data file in the DAS (Data Acquisition System) was over 20 GB. This report is a database that consists of the log list and the log sheets of every shot. One can access the database, make a search, and browse results via Internet (http://1ogwww.naka.jaeri.go.jp). The database will be useful to quick search to choose necessary shots. (author)

  2. Analysis and experimental study of wireless power transfer with HTS coil and copper coil as the intermediate resonators system

    International Nuclear Information System (INIS)

    Wang, Xiufang; Nie, Xinyi; Liang, Yilang; Lu, Falong; Yan, Zhongming; Wang, Yu

    2017-01-01

    Highlights: • We investigated a kind of system architecture with three coils which the repeater is copper coil or HTS coil. • We simulated the different repeater system and obtained the magnetic field distribution at different distance. • We used helical coil instead of pancake coil which does not use capacitors. • HTS intermediate coil has significant effect on improving the transmission efficiency and lengthening transmission distance than copper intermediate coil. - Abstract: Intermediate resonator (repeater) between transmitter and receiver can significantly increase the distance of wireless power transfer (WPT) and the efficiency of wireless power transfer. The wireless power transfer via strongly coupled magnetic resonances with an high temperature superconducting (HTS) coil and copper coil as intermediate resonators was presented in this paper. The electromagnetic experiment system under different conditions with different repeating coils were simulated by finite element software. The spatial distribution patterns of magnetic induction intensity at different distances were plotted. In this paper, we examined transfer characteristics with HTS repeating coil and copper repeating coil at 77 K and 300 K, respectively. Simulation and experimental results show that HTS and copper repeating coil can effectively enhance the space magnetic induction intensity, which has significant effect on improving the transmission efficiency and lengthening transmission distance. We found that the efficiency and the distance of wireless power transfer system with an HTS coil as repeater is much higher by using of copper coil as repeater.

  3. Analysis and experimental study of wireless power transfer with HTS coil and copper coil as the intermediate resonators system

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiufang [School of Electrical Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); School of Physics and Technology, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Nie, Xinyi [School of Electrical Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Liang, Yilang [School of Physics and Technology, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Lu, Falong [School of Electrical Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Yan, Zhongming, E-mail: wangxiufanghappy@163.com [School of Electrical Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Wang, Yu [School of Electrical Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China)

    2017-01-15

    Highlights: • We investigated a kind of system architecture with three coils which the repeater is copper coil or HTS coil. • We simulated the different repeater system and obtained the magnetic field distribution at different distance. • We used helical coil instead of pancake coil which does not use capacitors. • HTS intermediate coil has significant effect on improving the transmission efficiency and lengthening transmission distance than copper intermediate coil. - Abstract: Intermediate resonator (repeater) between transmitter and receiver can significantly increase the distance of wireless power transfer (WPT) and the efficiency of wireless power transfer. The wireless power transfer via strongly coupled magnetic resonances with an high temperature superconducting (HTS) coil and copper coil as intermediate resonators was presented in this paper. The electromagnetic experiment system under different conditions with different repeating coils were simulated by finite element software. The spatial distribution patterns of magnetic induction intensity at different distances were plotted. In this paper, we examined transfer characteristics with HTS repeating coil and copper repeating coil at 77 K and 300 K, respectively. Simulation and experimental results show that HTS and copper repeating coil can effectively enhance the space magnetic induction intensity, which has significant effect on improving the transmission efficiency and lengthening transmission distance. We found that the efficiency and the distance of wireless power transfer system with an HTS coil as repeater is much higher by using of copper coil as repeater.

  4. The IEA large coil task test results in IFSMTF

    International Nuclear Information System (INIS)

    Lubell, M.S.; Clinard, J.A.; Dresner, L.

    1987-01-01

    The Large Coil Task (LCT) is an international collaboration of the United States, EURATOM, Japan, and Switzerland to develop large superconducting magnets for fusion reactors. The testing phase of LCT was completed on September 3, 1987. All six coils exceeded the design goals, both as single coils and in six-coil toroidal tests. In addition, a symmetric torus test was performed in which a maximum field of 9 T was reached in all coils simultaneously. These are by far the largest magnets (either in size, weight, or stored energy) ever to achieve such a field. 6 refs., 6 figs., 3 tabs

  5. Instrumentation and test of the Swiss LCT-coil

    International Nuclear Information System (INIS)

    Zichy, J.A.; Horvath, I.; Jakob, B.; Marinucci, C.; Vecsey, G.; Weymuth, P.; Zellweger, J.

    1985-01-01

    Just before Christmas 1983 the fabrication of the Swiss LCT-coil was finished. Tests at ambient temperature were performed on the factory site and after delivery in Oak Ridge. To avoid an undesirable delay of the rescheduled Partial-Array Test it was agreed to install the coil without its superconducting bus. In July 1984 the Swiss LCT-coil was successfully cooled down to LHe temperature together with the other two fully installed coils. Besides the cooling system, the instrumentation, measured parameters of the coil and some preliminary results obtained during the ongoing Partial-Array Test are presented

  6. AC loss in superconducting wires operating in a wind turbine like generator

    DEFF Research Database (Denmark)

    Seiler, Eugen; Zirngibl, Thomas; Mijatovic, Nenad

    2010-01-01

    We have manufactured a small circular superconducting coil impregnated with epoxy fibreglass. The coil was wound from a Bi-2223/Ag superconducting wire and it was tested in liquid nitrogen at 77 K. Current-voltage characteristic and the AC losses of the coil were measured and compared...

  7. Magnetoelastic stability and vibrations of superconducting magnets. Progress report, September 1, 1975--March 31, 1976

    International Nuclear Information System (INIS)

    Moon, F.C.

    1976-05-01

    Buckling and vibration problems in small superconducting models of tokamak coils are studied. Observations are reported on thermoelastic buckling of epoxy potted superconducting coils producing significant out of plane deformations due to differences in thermal expansion coefficients. The damping of free vibrations in the coils is also investigated

  8. A coil test facility for the cryogenic tests of the JT-60SA TF coils

    International Nuclear Information System (INIS)

    Chantant, M.; Genini, L.; Bayetti, P.; Millet, F.; Wanner, M.; Massaut, V.; Corte, A. Della; Ardelier-Desage, F.; Catherine-Dumont, V.; Dael, A.; Decool, P.; Donati, A.; Duchateau, J.L.; Garibaldi, P.; Girard, S.; Hatchressian, J.C.; Fejoz, P.; Jamotton, P.; Jourdheuil, L.; Juster, F.P.

    2011-01-01

    In the framework of the Broader Approach Activities, the EU will deliver to Japan the 18 superconducting coils, which constitute the JT-60SA Toroidal field magnet. These 18 coils, manufactured by France and Italy, will be cold tested before shipping to Japan. For this purpose, the European Joint Undertaking for ITER, the Development of Fusion Energy ('Fusion for Energy', F4E) and the European Voluntary Contributors are collaborating to design and set-up a coil test facility (CTF) and to perform the acceptance test of the 18 JT-60SA Toroidal Field (TF) coils. The test facility is designed to test one coil at a time at nominal current and cryogenic temperature. The test of the first coil of each manufacturer includes a quench triggered by increasing the temperature. The project is presently in the detailed design phase.

  9. Large coil test facility conceptual design report

    International Nuclear Information System (INIS)

    Nelms, L.W.; Thompson, P.B.; Mann, T.L.

    1978-02-01

    In the development of a superconducting toroidal field (TF) magnet for The Next Step (TNS) tokamak reactor, several different TF coils, about half TNS size, will be built and tested to permit selection of a design and fabrication procedure for full-scale TNS coils. A conceptual design has been completed for a facility to test D-shaped TF coils, 2.5 x 3.5-m bore, operating at 4-6 K, cooled either by boiling helium or by forced-flow supercritical helium. Up to six coils can be accommodated in a toroidal array housed in a single vacuum tank. The principal components and systems in the facility are an 11-m vacuum tank, a test stand providing structural support and service connections for the coils, a liquid nitrogen system, a system providing helium both as saturated liquid and at supercritical pressure, coils to produce a pulsed vertical field at any selected test coil position, coil power supplies, process instrumentation and control, coil diagnostics, and a data acquisition and handling system. The test stand structure is composed of a central bucking post, a base structure, and two horizontal torque rings. The coils are bolted to the bucking post, which transmits all gravity loads to the base structure. The torque ring structure, consisting of beams between adjacent coils, acts with the bucking structure to react all the magnetic loads that occur when the coils are energized. Liquid helium is used to cool the test stand structure to 5 K to minimize heat conduction to the coils. Liquid nitrogen is used to precool gaseous helium during system cooldown and to provide thermal radiation shielding

  10. Startup of Large Coil Test Facility

    International Nuclear Information System (INIS)

    Haubenreich, P.N.; Bohanan, R.E.; Fietz, W.A.; Luton, J.N.; May, J.R.

    1984-01-01

    The Large Coil Test Facility (LCTF) is being used to test superconducting toroidal field coils about one-third the size of those for INTOR. Eventually, six different coils from four countries will be tested. Operations began in 1983 with acceptance testing of the helium refrigerator/liquefier system. Comprehensive shakedown of the facility and tests with the first three coils (from Japan, the United States, and Switzerland) were successfully accomplished in the summer of 1984. Currents up to 10,200 A and fields up to 6.4 T were reached. Data were obtained on performance of refrigerator, helium distribution, power supplies, controls, and data acquisition systems and on the acoustic emission, voltages, currents, and mechanical strains during charging and discharging the coils

  11. Startup of Large Coil Test Facility

    International Nuclear Information System (INIS)

    Haubenreich, P.N.; Bohanan, R.E.; Fietz, W.A.; Luton, J.N.; May, J.R.

    1985-01-01

    The Large Coil Test Facility (LCTF) is being used to test superconducting toroidal field coils about one-third the size of those for INTOR. Eventually, six different coils from four countries will be tested. Operations began in 1983 with acceptance testing of the helium refrigerator/liquefier system. Comprehensive shakedown of the facility and tests with the first three coils (from Japan, the United States, and Switzerland) were successfully accomplished in the summer of 1984. Currents up to 10,200 A and fields up to 6.4 T were reached. Data were obtained on performance of refrigerator, helium distribution, power supplies, controls, and data acquisition systems and on the acoustic emission, voltages, currents, and mechanical strains during charging and discharging the coils

  12. Device to measure elastic modulus of superconducting windings

    CERN Multimedia

    CERN PhotoLab

    1979-01-01

    This device was made to measure elastic modulus of the Po dipole superconducting coils. More elaborated devices, but based on the same concept, were later used to measure the apparent elastic moduli of the LHC superconducting magnet coils. See also 7903547X, 7901386.

  13. Superconducting magnetic energy storage for asynchronous electrical systems

    Science.gov (United States)

    Boenig, Heinrich J.

    1986-01-01

    A superconducting magnetic energy storage coil connected in parallel between converters of two or more ac power systems provides load leveling and stability improvement to any or all of the ac systems. Control is provided to direct the charging and independently the discharging of the superconducting coil to at least a selected one of the ac power systems.

  14. Sweeping a persisting superconducting magnet with a transformer

    International Nuclear Information System (INIS)

    Spencer, G.F.; Alexander, P.W.; Ihas, G.G.

    1982-01-01

    A method for sweeping a persisting superconducting magnet is described. The field sweep is achieved by including in the superconducting loop of the magnet a coil which acts as the secondary coil of a transformer. Variation of the current in the primary coil of the transformer, controlled from outside the cryostat, causes the field-sweeping action through flux-linking with the superconducting loop. Compared to directly changing the current in a magnet, this technique improves control by the ratio of the magnet's inductance to the transformer's inductance. The advantages of using an all-metal vacuum-tight superconducting feedthrough are discussed. (author)

  15. Radiofrequency amplifier based on a DC superconducting quantum interference device

    International Nuclear Information System (INIS)

    Martinis, J.M.; Hilbert, C.; Clarke, J.

    1986-01-01

    A method is described of amplifying a radiofrequency signal consisting of: disposing a single symmetrically biased dc SQUID and an input coil within a superconducting shield, the dc SQUID having a superconducting ring interrupted by two shunted Josephson junctions, and the input coil being inductively coupled solely to the ring of the single SQUID, establishing a constant magnetic flux threading the SQUID ring, applying the radiofrequency signal to the input coil from outside of the superconducting shield, obtaining an amplified radiofrequency signal solely from across the ring of the single SQUID, transmitting the amplified radiofrequency signal from across the SQUID ring to the outside of the superconducting shield

  16. Operation of a 400MHz NMR magnet using a (RE:Rare Earth)Ba2Cu3O7-x high-temperature superconducting coil: Towards an ultra-compact super-high field NMR spectrometer operated beyond 1GHz.

    Science.gov (United States)

    Yanagisawa, Y; Piao, R; Iguchi, S; Nakagome, H; Takao, T; Kominato, K; Hamada, M; Matsumoto, S; Suematsu, H; Jin, X; Takahashi, M; Yamazaki, T; Maeda, H

    2014-12-01

    High-temperature superconductors (HTS) are the key technology to achieve super-high magnetic field nuclear magnetic resonance (NMR) spectrometers with an operating frequency far beyond 1GHz (23.5T). (RE)Ba 2 Cu 3 O 7- x (REBCO, RE: rare earth) conductors have an advantage over Bi 2 Sr 2 Ca 2 Cu 3 O 10- x (Bi-2223) and Bi 2 Sr 2 CaCu 2 O 8- x (Bi-2212) conductors in that they have very high tensile strengths and tolerate strong electromagnetic hoop stress, thereby having the potential to act as an ultra-compact super-high field NMR magnet. As a first step, we developed the world's first NMR magnet comprising an inner REBCO coil and outer low-temperature superconducting (LTS) coils. The magnet was successfully charged without degradation and mainly operated at 400MHz (9.39T). Technical problems for the NMR magnet due to screening current in the REBCO coil were clarified and solved as follows: (i) A remarkable temporal drift of the central magnetic field was suppressed by a current sweep reversal method utilizing ∼10% of the peak current. (ii) A Z2 field error harmonic of the main coil cannot be compensated by an outer correction coil and therefore an additional ferromagnetic shim was used. (iii) Large tesseral harmonics emerged that could not be corrected by cryoshim coils. Due to those harmonics, the resolution and sensitivity of NMR spectra are ten-fold lower than those for a conventional LTS NMR magnet. As a result, a HSQC spectrum could be achieved for a protein sample, while a NOESY spectrum could not be obtained. An ultra-compact 1.2GHz NMR magnet could be realized if we effectively take advantage of REBCO conductors, although this will require further research to suppress the effect of the screening current. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Physics, technologies, and status of the Wendelstein 7-X device

    International Nuclear Information System (INIS)

    Wagner, F.; Andreeva, T.; Baldzuhn, J.

    2005-01-01

    W7-X is a fully optimised low-shear stellarator of the Wendelstein line. It follows the partially optimised W7-AS device which showed excellent operational characteristics at fusion relevant parameters. W7-X is optimised along the quasi-isodynamic principle. It is built with superconducting coils and ECRF heating and plasma exhaust are developed for 30 min operation. At present, the device is at the transition from component procurement to assembly. W7-X has a high ITER relevance and it represents an excellent training bed for European industry. (author)

  18. Measurement of a Conduction Cooled Nb3Sn Racetrack Coil

    Science.gov (United States)

    Kim, HS; Kovacs, C.; Rochester, J.; Sumption, MD; Tomsic, M.; Peng, X.; Doll, D.

    2017-12-01

    Use of superconducting coils for wind turbines and electric aircraft is of interest because of the potential for high power density and weight reduction. Here we test a racetrack coil developed as a proof-of-concept for cryogen-free superconducting motors and generators. The coil was wound with 1209 m of 0.7-mm-diameter insulated tube-type Nb3Sn wire. The coil was epoxy-impregnated, instrumented, covered with numerous layers of aluminized mylar insulation, and inserted vertically into a dewar. The system was cooled to 4.2 K, and a few inches of liquid helium was allowed to collect at the bottom of the dewar but below the coil. The coil was cooled by conduction via copper cooling bars were attached to the coil but also were immersed in the liquid helium at their lower ends. Several current tests were performed on the coil, initially in voltage mode, and one run in current mode. The maximum coil Ic at 4.2 K was 480 A, generating 3.06 T at the surface of the coil. The coil met the design targets with a noticeable margin.

  19. Design of self-correction coils in a superferric dipole magnet

    Indian Academy of Sciences (India)

    Design of self-correction coils in a superferric dipole magnet is carried out. By adopting the self-correction coil (SCC) scheme, we can do online correction of unwanted fields inside the magnet aperture during the whole operating cycle irrespective of their origin. The self-correction coils are short-circuited superconducting ...

  20. Axicell MFTF-B superconducting-magnet system

    International Nuclear Information System (INIS)

    Wang, S.T.; Bulmer, R.; Hanson, C.; Hinkle, R.; Kozman, T.; Shimer, D.; Tatro, R.; VanSant, J.; Wohlwend, J.

    1982-01-01

    The Axicell MFTF-B magnet system will provide the field environment necessary for tandem mirror plasma physics investigation with thermal barriers. The performance of the device will stimulate DT to achieve energy break-even plasma conditions. Operation will be with deuterium only. There will be 24 superconducting coils consisting of 2 sets of yin-yang pairs, 14 central-cell solenoids, 2 sets of axicell mirror-coil pairs, and 2 transition coils between the axicell mirror coil-pairs and the yin-yang coils. This paper describes the progress in the design and construction of MFTF-B Superconducting-Magnet System

  1. Stabilization of superconducting dry solenoids

    International Nuclear Information System (INIS)

    Urata, M.; Maeda, H.

    1989-01-01

    Premature quenches in superconducting solenoids, wound with Formvar coated NbTi conductors, have been studied. Some model coils were tested wound with various winding tensions. The experimental results are discussed considering the calculated stress distribution for coil winding, cool-down to liquid helium temperature, and energization at 4.2 K. /Some mechanisms of premature quenches are classified by the winding tension. Some stabilization methods are presented based on these quench mechanisms

  2. Superconducting current generators

    International Nuclear Information System (INIS)

    Genevey, P.

    1970-01-01

    After a brief summary of the principle of energy storage and liberation with superconducting coils,two current generators are described that create currents in the range 600 to 1400 A, used for two storage experiments of 25 kJ and 50 kJ respectively. The two current generators are: a) a flux pump and b) a superconducting transformer. Both could be developed into more powerful units. The study shows the advantage of the transformer over the flux pump in order to create large currents. The efficiencies of the two generators are 95 per cent and 40 to 60 per cent respectively. (author) [fr

  3. Superconductive energy storage magnet study

    International Nuclear Information System (INIS)

    Rhee, S.W.

    1982-01-01

    Among many methods of energy storages the superconducting energy storage has been considered as the most promising method. Many related technical problems are still unsolved. One of the problems is the magnetizing and demagnetizing loss of superconducting coil. This loss is mainly because of hysteresis of pinning force. In this paper the hysteresis loss is calculated and field dependence of the a.c. losses is explained. The ratio of loss and stored energy is also calculated. (Author)

  4. Design of superconducting corrector magnets for LHC

    International Nuclear Information System (INIS)

    Baynham, D.E.; Coombs, R.C.; Ijspeert, A.; Perin, R.

    1994-01-01

    The Large Hadron Collider (LHC) will require a range of superconducting corrector magnets. This paper presents the design of sextupole and decapole corrector coils which will be included as spool pieces adjacent to reach main ring dipole. The paper gives detailed 3D field computations of the coil configurations to meet LHC beam dynamics requirements. Coil protection within a long string environment is addressed and mechanical design outlines are presented

  5. Design of superconducting corrector magnets for LHC

    Science.gov (United States)

    Baynham, D. E.; Coombs, R. C.; Ijspeert, A.; Perin, R.

    1994-07-01

    The Large Hadron Collider (LHC) will require a range of superconducting corrector magnets. This paper presents the design of sextupole and decapole corrector coils which will be included as spool pieces adjacent to each main ring dipole. The paper gives detailed 3D field computations of the coil configurations to meet LHC beam dynamics requirements. Coil protection within a long string environment is addressed and mechanical design outlines are presented.

  6. Manufacture and mechanical test of a TORE SUPRA model coil

    International Nuclear Information System (INIS)

    Aymar, R.; Claudet, G.; Disdier, F.; Hamelin, J.; Libeyre, P.; Mayaux, G.; Meuris, C.; Parain, J.; Torossian, A.

    1980-09-01

    Inside the qualifying test programme, supporting the Tore Supra Design, a reduced scale model of a Bsub(T) coil was fabricated by a large industrial firm. This model coil is provided with the same features as those retained for the complete magnet. Tests of this model coil have been carried out in such a way that most of stresses which will arise in Tore Supra windings are simulated; simultaneously its cryogenic supply is fully representative of the system retained for the complete machine. Operation of the model coil has been found highly stable; under the conditions of applied field and forces a coil transition could be triggered, by an electrical heater located inside the coil, only when the temperature of the superfluid helium bath was close to Tsub(lambda). Thus, design and manufacturing techniques have been qualified satisfactorily to proceed to the next step: fabrication of the superconducting Bsub(T) coils of Tore Supra

  7. Demonstration poloidal coil test facility

    International Nuclear Information System (INIS)

    Sato, Masahiko; Kawano, Katumi; Tada, Eisuke

    1989-01-01

    A new compact cryogenic cold compressor was developed by Japan Atomic Energy Research Institute (JAERI) in collaboration with Isikawajima-Harima Heavy Industries Co., Ltd. (IHI) in order to produce the supercritical helium below 4.2 K for Demonstration Poloidal Coils (DPC) which are forced-flow cooled type superconducting pulse coils. This compressor is one of key components for DPC test facility. The cold compressor reduces pressure in liquid helium bath, which contains liquid helium of around 3,000 l, down to 0.5 atm efficiently. Consequently, supercritical helium down to 3.5 K is produced and supplied to the DPC coils. A centrifugal compressor with dynamic gas bearing is selected as a compressor mechanism to realize high adiabatic efficiency and large flow rate. In this performance tests, the compressor was operated for 220 h at saturated condition from 0.5 to 1.0 atm without any failure. High adiabatic efficiency (more than 60 %) is achieved with wide flow range (25-65 g/s) and the design value is fully satisfied. The compressor can rotate up to 80,000 rpm at maximum then the coil supply temperature of supercritical helium is 3.5 K. (author)

  8. Superconducting Panofsky quadrupoles

    International Nuclear Information System (INIS)

    Harwood, L.H.

    1981-01-01

    A design for a rectangular aperture quadrupole magnet without pole-tips was introduced by Hand and Panofsky in 1959. This design was quite radical but simple to construct. Few magnets of this design were ever built because of the large power needed. With the advent of superconducting coils there has been a renewed interest in them. The mathematical basis, field characteristics, and present and future construction of these magnets are described

  9. Low AC-Loss Superconducting Cable Technology for Electric Aircraft Propulsion, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The availability of low AC loss magnesium diboride (MgB2) superconducting wires enables much lighter weight superconducting stator coils than with any other metal or...

  10. Split coil made of (RE)BCO pancake coils for IC(B) anisotropy measurements of superconductors

    International Nuclear Information System (INIS)

    Frolek, L; Pardo, E; Gömöry, F; Šouc, J; Pitel, J

    2014-01-01

    Measurement of the I c (B) anisotropy is standard characterization of superconducting tapes, wires or cables. This contribution presents a split coil consisting on two superconducting pancake coils in order to generate the magnetic field necessary for this kind of measurement. Both coils were made using (RE)BCO – based second generation (2G) coated conductor tape with cross section 0.1 mm × 12 mm. The individual turns of the tape were insulated by a fiberglass tape without impregnation. These coils have identical inner and outer diameter and number of turns. Their inner and outer diameters are 50 mm and 80 mm, respectively, and they have 62 turns. The length of conductor in each coil is approximately 13 m. The distance between both pancake coils is 22 mm. Individual coils and the complete split coil were characterized in liquid nitrogen bath. Their parameters, like the critical currents, E(I) characteristics and magnetic field of complete split coil, were measured and interpreted. The split coil can be used up to magnetic fields of 210 mT. The length between the potential taps on the sample can be up to 20 mm, while the magnetic field decrease is lower than 1% on this length.

  11. Transformer current sensor for superconducting magnetic coils

    Science.gov (United States)

    Shen, S.S.; Wilson, C.T.

    1985-04-16

    The present invention is a current transformer for operating currents larger than 2kA (two kiloamps) that is capable of detecting a millivolt level resistive voltage in the presence of a large inductive voltage. Specifically, the present invention includes substantially cylindrical primary turns arranged to carry a primary current and substantially cylindrical secondary turns arranged coaxially with and only partially within the primary turns, the secondary turns including an active winding and a dummy winding, the active and dummy windings being coaxial, longitudinally separated and arranged to mutually cancel voltages excited by commonly experienced magnetic fields, the active winding but not the dummy winding being arranged within the primary turns.

  12. OCLATOR (One Coil Low Aspect Toroidal Reactor)

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, S.

    1980-02-01

    A new approach to construct a tokamak-type reactor(s) is presented. Basically the return conductors of toroidal field coils are eliminated and the toroidal field coil is replaced by one single large coil, around which there will be placed several tokamaks or other toroidal devices. The elimination of return conductors should, in addition to other advantages, improve the accessibility and maintainability of the tokamaks and offer a possible alternative to the search for special materials to withstand large neutron wall loading, as the frequency of changeover would be increased due to minimum downtime. It also makes it possible to have a low aspect ratio tokamak which should improve the ..beta.. limit, so that a low toroidal magnetic field strength might be acceptable, meaning that the NbTi superconducting wire could be used. This system is named OCLATOR (One Coil Low Aspect Toroidal Reactor).

  13. Switching transients in the MFTF yin-yang coils

    International Nuclear Information System (INIS)

    Owen, E.W.; Shimer, D.W.

    1982-01-01

    This report is a study of the transients caused by the fast dump of large superconducting coils. Theoretical analysis, computer simulation, and actual measurements are used. Theoretical analysis can only be applied to the simplest of models. In the computer simulations two models are used, one in which the coil is divided into ten segments and another in which a single coil is employed. The circuit breaker that interrupts the current to the power supply, causing a fast dump, is represented by a time and current dependent conductance. Actual measurements are limited to measurements made incidental to the coils' performance tests

  14. Superconducting current transducer

    International Nuclear Information System (INIS)

    Kuchnir, M.; Ozelis, J.P.

    1990-10-01

    The construction and performance of an electric current meter that operates in liquid He and mechanically splits apart to permit replacement of the current carrying conductor is described. It permits the measurement of currents induced in a loop of superconducting cable and expeditious exchange of such loops. It is a key component for a short sample cable testing facility that requires no high current power supplies nor high current leads. Its superconducting pickup circuit involves a non-magnetic core toroidal split-coil that surrounds the conductor and a solenoid whose field is sensed by a Hall probe. This toroidal split-coil is potted inside another compensating toroidal split-coil. The C shaped half toroids can be separated and brought precisely together from outside the cryostat. The Hall probe is energized and sensed by a lock-in amplifier whose output drives a bipolar power supply which feeds the compensating coil. The output is the voltage across a resistor in this feedback circuit. Currents of up to 10 kA can be measured with a precision of 150 mA. 3 refs., 4 figs

  15. Design of an 18 Tesla, tandem mirror, fusion reactor, hybrid choke coil

    International Nuclear Information System (INIS)

    Parmer, J.F.; Agarwal, K.; Gurol, H.; Mancuso, A.; Michels, P.H.; Peck, S.D.; Burgeson, J.; Dalder, E.N.

    1987-01-01

    A hybrid, part normal part superconducting 18-Tesla solenoid choke coil is designed for a tandem mirror fusion reactor. The present state of the art is represented by the 12-Tesla, superconducting NbSn coil. Future applications other than tandem mirror fusion devices needing high field solenoids might require hybrid magnets of the type described herein. The hybrid design was generated because of critical field performance limitations on present, practical superconducting wires. A hybrid design might be required (due to structural limits) even if the critical field were higher. Also, hybrids could be a cost-effective way of getting very high fields for certain applications. The 18-Tesla solenoid described is composed of an inner coil made of water-cooled, high-strength zirconium copper which generates 3 Tesla. A superconducting NbSn background coil contributes the remaining 15 Tesla. The focus of the design study was on the inner coil. Demonstration fabrication and testing was performed

  16. Superconductivity in the 1990's

    International Nuclear Information System (INIS)

    Stekly, Z.J.J.

    1990-01-01

    Superconducting magnets, coils or windings are the basis for a range of major applications in the energy area such as energy storage in superconducting coils, magnets for fusion research, and rotating machinery. Other major applications of superconductivity include high energy physics where 1000 superconducting magnets are operated continuously in the Tevatron at Fermilab in Illinois, over 12,000 superconducting magnets will be required for the superconducting Super Collider being build near Dallas. The largest commercial application of superconductors is in magnets for magnetic resonance imaging (MRI) - a new medical diagnostic imaging technique with about 2,000 systems installed worldwide. These form a sizable technology base on which to evaluate and push forward applications such as magneto hydrodynamic propulsion of seagoing vessels. The attractiveness of which depends ultimately on the characteristics of the superconducting magnet. The magnet itself is a combination of several technology areas - the conductors, magnetics, structures and cryogenics. This paper reviews state-of-the-art in each of the technology areas as they relate to superconductors

  17. Superconducting magnets for HERA

    International Nuclear Information System (INIS)

    Wolff, S.

    1987-01-01

    The Hadron-Electron-Ring Accelerator (HERA) presently under construction at DESY, Hamburg, consists of an electron storage ring of 30 GeV and a proton storage ring of 820 GeV. Superconducting magnets are used for the proton ring. There are 416 superconducting bending magnets of 4.698 T central field and 8.824 m magnetic length, 224 superconducting quadrupoles of 91.2 T/m central gradient and many superconducting correction dipoles, quadrupoles and sextupoles. The main dipoles and quadrupoles consist of two-layer coils of 75 mm inner diameter clammed with aluminium (for the dipoles) or stainless steel laminations (for the quadrupoles). The collared coils are surrounded by a laminated cold iron yoke and supported inside a low loss cryostat. The protection system uses cold diodes to bypass the current around a quenching magnet. The magnets are cooled with one phase helium supplied by a 3 block central refrigeration system of 20 kW refrigeration power at 4.3 K. Two helium is returned through the magnets in good thermal contact with the one phase helium in the dipoles for temperature control. This paper describes the magnet system and gives the results obtained for prototype magnets

  18. Applied superconductivity

    CERN Document Server

    Newhouse, Vernon L

    1975-01-01

    Applied Superconductivity, Volume II, is part of a two-volume series on applied superconductivity. The first volume dealt with electronic applications and radiation detection, and contains a chapter on liquid helium refrigeration. The present volume discusses magnets, electromechanical applications, accelerators, and microwave and rf devices. The book opens with a chapter on high-field superconducting magnets, covering applications and magnet design. Subsequent chapters discuss superconductive machinery such as superconductive bearings and motors; rf superconducting devices; and future prospec

  19. Superconducting generators and motors and methods for employing same

    Energy Technology Data Exchange (ETDEWEB)

    Tomsic, Michael J.; Long, Larry

    2017-08-29

    A superconducting electrical generator or motor having a plurality of cryostats is described. The cryostats contain coolant and a first cryostat encloses at least one of a plurality of superconducting coils. A first coil is in superconducting electrical communication with a second coil contained in a second cryostat through a superconducting conduction cooling cable enclosing a conductor. The first cryostat and the second cryostat may be in fluid communication through at least one cryogen channel within the at least one superconducting conduction cooling cable. In other embodiments, none of the plurality of cryostats may be in fluid communication and the cable may be cooled by conduction along the conductor from the first or second cryostat, or from both. The conductor may have different segments at temperatures equal to or above the temperature of the coolant and the superconducting conduction cooling cables may be connected through quick connect fittings.

  20. Experimental study of the effects of alternating fields on HTS coils according to the winding insulation conditions

    International Nuclear Information System (INIS)

    Hwang, Y J; Lee, T S; Lee, W S; Ko, T K; Ahn, M C

    2013-01-01

    This paper examines the effects of alternating fields on high-temperature superconducting (HTS) coils according to the winding insulation condition. Alternating fields can occur in synchronous machines (armature reaction, faults) and other devices. In superconducting synchronous machines, alternating fields affect the operational characteristics of the machine and the superconducting field coil. Therefore, a method of reducing the effects of alternating fields is necessary in superconducting synchronous design. In this study, the effects of alternating fields on the HTS field coil according to the winding insulation condition were experimentally evaluated. The experimental results show that HTS coils made using the no-insulation technique can be a solution for reducing the effects of the alternating field. These results are expected to suggest useful data for applications of HTS field coils in superconducting synchronous machines. (paper)

  1. A liquid helium piston pump with a superconducting drive

    International Nuclear Information System (INIS)

    Schmidt, C.

    1984-01-01

    This chapter describes a bellows pump where the driving force is achieved by an arrangement of three superconducting coils. The pump was designed for use in the supercritical helium flow circuit of the LCT-conductor test facility. The main advantage of the superconducting drive, compared to conventional pumps with external drive, is the compact design. Force transferring parts between 4.2 K and room temperature are not necessary. The pump was tested in a closed loop arrangement. The superconducting drive for a piston pump consists of a moving coil in a constant background field. Other coil configurations and the upscaling of the pump design are discussed

  2. TNS superconducting ohmic-heating system

    International Nuclear Information System (INIS)

    Wang, S.T.; Fuja, R.; Kim, S.H.; Kustom, R.L.; Praeg, W.F.; Thompson, K.; Turner, L.R.

    1978-01-01

    The superconducting ohmic-heating (OH) system is the selected design for the General Atomics Co./Argonne National Laboratory TNS tokamak design studies. The key features of the OH system design are: (1) parallel coil connection, (2) better utilization of flux core by embedding support cylinder of the toroidal-field coil within the OH inner radius, (3) independent trim coils for correcting the stray fields, (4) low-loss high-current cryostable cable design and (5) OH coil cycling circuit using a reversing bridge. Detailed designs are presented

  3. Inductive voltage compensation in superconducting magnet systems

    International Nuclear Information System (INIS)

    Yeh, H.T.; Goddard, J.S.; Shen, S.S.

    1979-01-01

    This paper details several techniques of inductive voltage compensation developed for quench detection in superconducting magnet systems with multiple coils and power supplies, with particular application for the Large Coil Test Facility (LCTF). Sources of noise, their magnitudes, and the sensitivity required for normal zone detection to avoid damage to the magnets are discussed. Two passive compensation schemes (second difference and central difference) are introduced and illustrated by parameters of LCTF; these take advantage of coil symmetries and other system characteristics. An active compensation scheme based on current rate input fom pickup coils and utilizing theory on ac loss voltage for calibration was tested, and the experimental setup and test results are discussed

  4. Conception of Brownian coil

    OpenAIRE

    Zhang, Jiayuan

    2018-01-01

    This article proposes a conception of Brownian coil. Brownian coil is a tiny coil with the same size of pollen. Once immersed into designed magnetic field and liquid, the coil will be moved and deformed macroscopically, due to the microscopic thermodynamic molecular collisions. Such deformation and movement will change the magnetic flux through the coil, by which an ElectroMotive Force (EMF) is produced. In this work, Brownian heat exchanger and Brownian generator are further designed to tran...

  5. Studies on a Stellarator reactor of the Helias type: The modular coil system

    International Nuclear Information System (INIS)

    Harmeyer, E.; Kisslinger, J.; Rau, F.; Wobig, H.

    1993-02-01

    Helias Stellarator Reactors (HSR) are considered, focussing on the superconducting modular coil system which generates the magnetic field, aiming to clarify critical issues of such systems. The development of the coil system is presented and the properties of the vacuum magnetic field are discussed. Electromagnetic forces and the resulting mechanical stresses and strains inside the coils and the surrounding structure are calculated. Parameter studies are made varying the major radius R 0 between 18 m and 24 m in order to investigate the engineering parameters for the superconducting coil system. The total mass and the fusion power output of HSR are compared with values evaluated for tokamak reactors. (orig.). 36 figs

  6. Mechanical behavior of the ATLAS B0 model coil

    CERN Document Server

    Foussat, A; Acerbi, E; Alessandria, F; Berthier, R; Broggi, F; Daël, A; Dudarev, A; Mayri, C; Miele, P; Reytier, M; Rossi, L; Sorbi, M; Sun, Z; ten Kate, H H J; Vanenkov, I; Volpini, G

    2002-01-01

    The ATLAS B0 model coil has been developed and constructed to verify the design parameters and the manufacture techniques of the Barrel Toroid coils (BT) that are under construction for the ATLAS Detector. Essential for successful operation is the mechanical behavior of the superconducting coil and its support structure. In the ATLAS magnet test facility, a magnetic mirror is used to reproduce in the model coil the electromagnetic forces of the BT coils when assembled in the final Barrel Toroid magnet system. The model coil is extensively equipped with mechanical instrumentation to monitor stresses and force levels as well as contraction during a cooling down and excitation up to nominal current. The installed set up of strain gauges, position sensors and capacitive force transducers is presented. Moreover the first mechanical results in terms of expected main stress, strain and deformation values are presented based on detailed mechanical analysis of the design. (7 refs).

  7. Modeling the static fringe field of superconducting magnets.

    Science.gov (United States)

    Jeglic, P; Lebar, A; Apih, T; Dolinsek, J

    2001-05-01

    The resonance frequency-space and the frequency gradient-space relations are evaluated analytically for the static fringe magnetic field of superconducting magnets used in the NMR diffusion measurements. The model takes into account the actual design of the high-homogeneity magnet coil system that consists of the main coil and the cryoshim coils and enables a precise calibration of the on-axis magnetic field gradient and the resonance frequency inside and outside of the superconducting coil. Copyright 2001 Academic Press.

  8. Split-coil-system SULTAN

    International Nuclear Information System (INIS)

    Vecsey, G.

    1992-08-01

    The high field superconductor test facility SULTAN started operation successfully in May 1992. Originally designed for testing full scale conductors for the large magnets of the next generation fusion reactors, the SULTAN facility installed at PSI (Switzerland) was designed as a common venture of three European Laboratories: ENEA (Italy), ECN (Netherlands) and PSI, and built by ENEA and PSI in the framework of the Euratom Fusion Technology Program. Presently the largest facility in the world, with its superconducting split coil system generating 11 Tesla in a 0.6 m bore, it is ready now for testing superconductor samples with currents up to 50 kA at variable cooling conditions. Similar tests can be arranged also for other applications. SULTAN is offered by the European Community as a contribution to the worldwide cooperation for the next step of fusion reactor development ITER. First measurements on conductor developed by CEA (Cadarache) are now in progress. Others like those of ENEA and CERN will follow. For 1993, a test of an Italian 12 TZ model coil for fusion application is planned. SULTAN is a worldwide unique facility marking the competitive presence of Swiss technology in the field of applied superconductivity research. Based on development and design of PSI, the high field Nb 3 Sn superconductors and coils were fabricated at the works of Kabelwerke Brugg and ABB, numerous Swiss companies contributed to the success of this international effort. Financing of the Swiss contribution of SULTAN was made available by NEFF, BEW, BBW, PSI and EURATOM. (author) figs., tabs., 20 refs

  9. Superconductors for W VII-X coils

    International Nuclear Information System (INIS)

    Maurer, W.

    1987-01-01

    Superconductor concepts are discussed with respect to operational current, cooling and bending behavior, and ac losses. The encouraging results for NbTi superconducting technology are recalled. It is argued that the WVII-X stellarator modular superconducting coils can be built just as the modular Cu coils for WVII-AS. Special attention must be paid to the dB/dt allowed for the conductor. Shape and price depend on the means used to avoid ac losses. Formula to elucidate the main physical parameters influencing ac loss behavior of superconductors are given. Configurations investigated with respect to plasma behavior are compared. Masses to be cooled were estimated for two configurations. The estimated cooling power is of the order of 3kW

  10. Superconducting magnets for toroidal fusion reactors

    International Nuclear Information System (INIS)

    Haubenreich, P.N.

    1980-01-01

    Fusion reactors will soon be employing superconducting magnets to confine plasma in which deuterium and tritium (D-T) are fused to produce usable energy. At present there is one small confinement experiment with superconducting toroidal field (TF) coils: Tokamak 7 (T-7), in the USSR, which operates at 4 T. By 1983, six different 2.5 x 3.5-m D-shaped coils from six manufacturers in four countries will be assembled in a toroidal array in the Large Coil Test Facility (LCTF) at Oak Ridge National Laboratory (ORNL) for testing at fields up to 8 T. Soon afterwards ELMO Bumpy Torus (EBT-P) will begin operation at Oak Ridge with superconducting TF coils. At the same time there will be tokamaks with superconducting TF coils 2 to 3 m in diameter in the USSR and France. Toroidal field strength in these machines will range from 6 to 9 T. NbTi and Nb 3 Sn, bath cooling and forced flow, cryostable and metastable - various designs are being tried in this period when this new application of superconductivity is growing and maturing

  11. Superconducting inductive displacement detection of a microcantilever

    Science.gov (United States)

    Vinante, A.

    2014-07-01

    We demonstrate a superconducting inductive technique to measure the displacement of a micromechanical resonator. In our scheme, a type I superconducting microsphere is attached to the free end of a microcantilever and approached to the loop of a dc Superconducting Quantum Interference Device (SQUID) microsusceptometer. A local magnetic field as low as 100 μT, generated by a field coil concentric to the SQUID, enables detection of the cantilever thermomechanical noise at 4.2 K. The magnetomechanical coupling and the magnetic spring are in good agreement with image method calculations assuming pure Meissner effect. These measurements are relevant to recent proposals of quantum magnetomechanics experiments based on levitating superconducting microparticles.

  12. Mechanical Design of Superconducting Accelerator Magnets

    International Nuclear Information System (INIS)

    Toral, F

    2014-01-01

    This paper is about the mechanical design of superconducting accelerator magnets. First, we give a brief review of the basic concepts and terms. In the following sections, we describe the particularities of the mechanical design of different types of superconducting accelerator magnets: solenoids, costheta, superferric, and toroids. Special attention is given to the pre-stress principle, which aims to avoid the appearance of tensile stresses in the superconducting coils. A case study on a compact superconducting cyclotron summarizes the main steps and the guidelines that should be followed for a proper mechanical design. Finally, we present some remarks on the measurement techniques

  13. Mechanical Design of Superconducting Accelerator Magnets

    CERN Document Server

    Toral, Fernando

    2014-07-17

    This paper is about the mechanical design of superconducting accelerator magnets. First, we give a brief review of the basic concepts and terms. In the following sections, we describe the particularities of the mechanical design of different types of superconducting accelerator magnets: solenoids, costheta, superferric, and toroids. Special attention is given to the pre-stress principle, which aims to avoid the appearance of tensile stresses in the superconducting coils. A case study on a compact superconducting cyclotron summarizes the main steps and the guidelines that should be followed for a proper mechanical design. Finally, we present some remarks on the measurement techniques.

  14. Mechanical Design of Superconducting Accelerator Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Toral, F [Madrid, CIEMAT (Spain)

    2014-07-01

    This paper is about the mechanical design of superconducting accelerator magnets. First, we give a brief review of the basic concepts and terms. In the following sections, we describe the particularities of the mechanical design of different types of superconducting accelerator magnets: solenoids, costheta, superferric, and toroids. Special attention is given to the pre-stress principle, which aims to avoid the appearance of tensile stresses in the superconducting coils. A case study on a compact superconducting cyclotron summarizes the main steps and the guidelines that should be followed for a proper mechanical design. Finally, we present some remarks on the measurement techniques.

  15. Prototype superconducting magnet for the FFAG accelerator

    International Nuclear Information System (INIS)

    Obana, T.; Ogitsu, T.; Yamamoto, A.; Yoshimoto, M.; Mori, Y.; Fujii, T.; Iwasa, M.; Orikasa, T.

    2006-01-01

    A study of a superconducting magnet for the Fixed Field Alternating Gradient (FFAG) accelerator has been performed. The FFAG accelerator requires static magnetic field, and it is suitable for superconducting magnet applications, because problems associated with time varying magnetic field such as eddy current loss can be eliminated. The superconducting magnet, which can generate high magnetic field, is possible to realize a higher beam energy with a given accelerator size or the size to be smaller for a given beam energy. The FFAG accelerator magnet is demanded to have a complicated nonlinear magnetic field with high accuracy. As a first prototype superconducting coil, the coil configuration which consists of left-right asymmetric cross-section and large aperture has been designed. The prototype coil has been successfully developed by using a 6-axis Computer Numerical Control (CNC) winding machine. The magnetic field of the prototype coil has been demonstrated in warm measurement. As a consequence, the technical feasibility has been verified with the prototype coil development and the performance test. In addition, the technology components developed in the prototype coil have a possibility to transfer to a fusion magnet

  16. LLNL high-field coil program

    International Nuclear Information System (INIS)

    Miller, J.R.

    1986-01-01

    An overview is presented of the LLNL High-Field Superconducting Magnet Development Program wherein the technology is being developed for producing fields in the range of 15 T and higher for both mirror and tokamak applications. Applications requiring less field will also benefit from this program. In addition, recent results on the thermomechanical performance of cable-in-conduit conductor systems are presented and their importance to high-field coil design discussed

  17. Productive international collaboration in the large coil task

    International Nuclear Information System (INIS)

    Haubenreich, P.N.; Komarek, P.; Shimamoto, S.; Vecsey, G.

    1987-01-01

    The Large Coil Task (LCT), initiated in 1977, has been very productive of useful technical information about superconducting toroidal field (TF) coil design and manufacture. Moreover, it has demonstrated close international collaboration in fusion technology development, including integration of large components built in four different countries. Each of six 40-t test coils was designed and produced by a major industrial team, with government laboratory guidance, to a common set of specifications. The six were assembled into a toroidal array for testing in the International Fusion Superconducting Magnet Test Facility (IFSMTF) at Oak Ridge. Testing was done by a team of representatives of EURATOM, Japan, Switzerland, and the United States, with each participant having full access to all data. Coils were thoroughly instrumented, enabling penetrating analysis of behavior

  18. A step towards controlled fusion reactors: Tore Supra tokamak with superconducting magnets

    International Nuclear Information System (INIS)

    Turck, B.

    1988-01-01

    Tore Supra technology has to solve all the problems related to the development and the installaion of superconducting coils and associated cryogenic devices. Tore Supra will allow to get a significative experience to prepare next machines. Specifications and needs of tokamaks concerning the superconducting coils of future machines are recalled [fr

  19. CS model coil experimental log book

    Energy Technology Data Exchange (ETDEWEB)

    Nishijima, Gen; Sugimoto, Makoto; Nunoya, Yoshihiko; Wakabayashi, Hiroshi; Tsuji, Hiroshi [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    2001-02-01

    Charging test of the ITER CS Model Coil which is the world's largest superconducting pulse coil and the CS Insert Coil had started at April 11, 2000 and had completed at August 18, 2000. In the campaign, total shot numbers were 356 and the size of the data file in the DAS (Data Acquisition System) was over 20 GB. This report is a database that consists of the log list and the log sheets of every shot. One can access the database, make a search, and browse results via Internet (http://1ogwww.naka.jaeri.go.jp). The database will be useful to quick search to choose necessary shots. (author)

  20. OCLATOR (One Coil Low Aspect Toroidal Reactor)

    International Nuclear Information System (INIS)

    Yoshikawa, S.

    1980-02-01

    A new approach to construct a tokamak-type reactor(s) is presented. Basically the return conductors of toroidal field coils are eliminated and the toroidal field coil is replaced by one single large coil, around which there will be placed several tokamaks or other toroidal devices. The elimination of return conductors should, in addition to other advantages, improve the accessibility and maintainability of the tokamaks and offer a possible alternative to the search for special materials to withstand large neutron wall loading, as the frequency of changeover would be increased due to minimum downtime. It also makes it possible to have a low aspect ratio tokamak which should improve the β limit, so that a low toroidal magnetic field strength might be acceptable, meaning that the NbTi superconducting wire could be used. This system is named OCLATOR

  1. Considerations against a force compensated coil

    International Nuclear Information System (INIS)

    Hassenzahl, W.

    1988-08-01

    The cost of structural components in a large superconducting coil may well exceed the coil and cryostat cost. As a result, the idea of constructing a system composed of two different coil types assembled in such a way that the sources balance and reduce the total structural requirement is oft proposed. A suitable geometry has never been found for the fundamental reason that there can be no force compensated solution. In this paper, the general problem is presented and an analysis of the energy stored and stresses produced in the structure are described in a fundamental way. Finally, the relation between structural mass M and stored energy E, M ≥/rho/E/σ/sub w/, that is valid for all magnetic systems is developed, where /rho/ is the density of the structure and σ/sub w/ is the working stress in the structure. 12 refs., 2 figs

  2. Considerations against a force compensated coil

    International Nuclear Information System (INIS)

    Hassenzahl, W.

    1988-08-01

    The cost of structural components in a large superconducting coil may well exceed the coil and cryostat cost. As a result, the idea of constructing a system composed of two different coil types assembled in such a way that the forces balance and reduce the total structural requirement is oft proposed. A suitable geometry has never been found for the fundamental reason that there can be no force compensated solution. In this paper, the general problem is presented and an analysis of the energy stored and stresses produced in the structure are described in a fundamental way. Finally, the relation between structural mass M and stored energy E, M ≥ /rho/E/σ/sub w/, that is valid for all magnetic systems is developed, where /rho/ is the density of the structure and σ/sub w/ is the working stress in the structure. 8 refs., 2 figs

  3. Structural analysis of the NET toroidal field coils and conductor

    International Nuclear Information System (INIS)

    Mitchell, N.; Collier, D.; Gori, R.

    1989-01-01

    The NET toroidal field coils will utilise A15-type superconductor at 4.2 K to generate fields up to 11.5 T. The superconductor strands themselves are sensitive to strain, which causes degradation of their current carrying capacity, and thus the detailed behaviour of the coil conductor must be analysied so that the strian can be minimised. This analysis must include the manufacturing processes of the conductor as well as the normal and abnormal loperational loads. The conductor will be insulated and bonded by glass fibre reinforced epoxy resin, with limited bonding shear strength, and the overall support of the complete coil system must be designed to reduce these shear stresses. The coils will be subjected to pulse loads form the poloidal field coils, and analysis of the slip between the various coil components, such as conductors and the coil case, giving rise to frictional heating and possible loss of superconducting properties is another important factor, which has been investigated by a number of stress analyses. The manufacturing, thermal and normal magnetic loads on the coils and the analysis leading to the proposed structural design are described. In addition to the normal operating conditions, there is a range of abnormal load conditions which could result from electrical or mechanical faults on the coils. The effect of these potential faults has been analysed and the coil design modified to prevent catastrophic structural failure. (author). 13 refs.; 8 figs.; 1 tab

  4. A superconducting large-angle magnetic suspension. Final report

    International Nuclear Information System (INIS)

    Downer, J.R.; Anastas, G.V. Jr.; Bushko, D.A.; Flynn, F.J.; Goldie, J.H.; Gondhalekar, V.; Hawkey, T.J.; Hockney, R.L.; Torti, R.P.

    1992-12-01

    SatCon Technology Corporation has completed a Small Business Innovation Research (SBIR) Phase 2 program to develop a Superconducting Large-Angle Magnetic Suspension (LAMS) for the NASA Langley Research Center. The Superconducting LAMS was a hardware demonstration of the control technology required to develop an advanced momentum exchange effector. The Phase 2 research was directed toward the demonstration for the key technology required for the advanced concept CMG, the controller. The Phase 2 hardware consists of a superconducting solenoid ('source coils') suspended within an array of nonsuperconducting coils ('control coils'), a five-degree-of-freedom positioning sensing system, switching power amplifiers, and a digital control system. The results demonstrated the feasibility of suspending the source coil. Gimballing (pointing the axis of the source coil) was demonstrated over a limited range. With further development of the rotation sensing system, enhanced angular freedom should be possible

  5. Test results of a 5 kW fully superconducting homopolar motor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. K. [Woosuk University, Wanju (Korea, Republic of); Park, S. H.; Kim, Y.; Lee, S.; Joo, H. G.; Kim, W. S.; Choi, K. [Korea Polytechnic University,Siheong (Korea, Republic of); Hahm, S. Y. [Electrical Engineering and Science Research Institute,Seoul (Korea, Republic of)

    2013-05-15

    The superconducting Homopolar motor is manufactured and tested. Homopolar motor system is simple and solid as the field coil of the motor is fixed near the stator coil without rotating system. In this paper, a 5 kW fully superconducting homopolar motor which has high temperature superconducting armature and field coils is manufactured and tested in liquid nitrogen. The critical current test results of the used 2G superconducting wire, pancake coil for rotor winding and race-track coils for armature winding are reported. Also, the test result of rotating and operating performance is presented. The operating frequency is to be 5 Hz for low-speed rotating. The developed fully superconducting Homopolar motor is the world's first.

  6. Test results of a 5 kW fully superconducting homopolar motor

    International Nuclear Information System (INIS)

    Lee, J. K.; Park, S. H.; Kim, Y.; Lee, S.; Joo, H. G.; Kim, W. S.; Choi, K.; Hahm, S. Y.

    2013-01-01

    The superconducting Homopolar motor is manufactured and tested. Homopolar motor system is simple and solid as the field coil of the motor is fixed near the stator coil without rotating system. In this paper, a 5 kW fully superconducting homopolar motor which has high temperature superconducting armature and field coils is manufactured and tested in liquid nitrogen. The critical current test results of the used 2G superconducting wire, pancake coil for rotor winding and race-track coils for armature winding are reported. Also, the test result of rotating and operating performance is presented. The operating frequency is to be 5 Hz for low-speed rotating. The developed fully superconducting Homopolar motor is the world's first.

  7. Water cooling coil

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, S; Ito, Y; Kazawa, Y

    1975-02-05

    Object: To provide a water cooling coil in a toroidal nuclear fusion device, in which coil is formed into a small-size in section so as not to increase dimensions, weight or the like of machineries including the coil. Structure: A conductor arranged as an outermost layer of a multiple-wind water cooling coil comprises a hollow conductor, which is directly cooled by fluid, and as a consequence, a solid conductor disposed interiorly thereof is cooled indirectly.

  8. Safety concerns for superconducting magnets of upcoming fusion experiments

    International Nuclear Information System (INIS)

    Turner, L.R.

    1983-01-01

    -Several fusion experiments being constructed (Tore Supra) or contemplated (DCT 8, Alcator DCT) feature superconducting coils. These coils introduce the following safety concerns: 1. Internally Cooled Conductor (ICC). ICC's are found to be highly stable against short heat pulses, even when the coolant is stagnant or moving at low steady-state velocity. However, a large heat pulse is certain to quench the conductor. Thus, determining the stability limits is vital. 2. Helium II Cooling. Helium II has both unique advantages as a coolant and unique safety problems. 3. Shorted Turns. In magnets with shorts from operational accidents, the current can switch back and forth between the short and the shorted turns, as those alternatively go normal and superconducting. 4. Hybrid Superconducting-Normal Conducting Coil System. The possibility of unequal currents in the different magnets and thus of unexpected forces on the superconducting magnets is much greater than for an all-superconducting system. Analysis of these problems are presented

  9. The superconducting magnet system for the Tokamak Physics Experiment

    International Nuclear Information System (INIS)

    Lang, D.D.; Bulmer, R.J.; Chaplin, M.R.; O'Connor, T.G.; Slack, D.S.; Wong, R.L.; Zbasnik, J.P.; Schultz, J.H.; Diatchenko, N.; Montgomery, D.B.

    1994-01-01

    The superconducting magnet system for the Tokamak Physics eXperiment (TPX) will be the first all superconducting magnet system for a Tokamak, where the poloidal field coils, in addition to the toroidal field coils are superconducting. The magnet system is designed to operate in a steady state mode, and to initiate the plasma discharge ohmically. The toroidal field system provides a peak field of 4.0 Tesla on the plasma axis at a plasma major radius of 2.25 m. The peak field on the niobium 3-tin, cable-in-conduit (CIC) conductor is 8.4 Tesla for the 16 toroidal field coils. The toroidal field coils must absorb approximately 5 kW due to nuclear heating, eddy currents, and other sources. The poloidal field system provides a total of 18 volt seconds to initiate the plasma and drive a plasma current up to 2 MA. The poloidal field system consists of 14 individual coils which are arranged symmetrically above and below the horizontal mid plane. Four pairs of coils make up the central solenoid, and three pairs of poloidal ring coils complete the system. The poloidal field coils all use a cable-in-conduit conductor, using either niobium 3-tin (Nb 3 Sn) or niobium titanium (NbTi) superconducting strands depending on the operating conditions for that coil. All of the coils are cooled by flowing supercritical helium, with inlet and outlet connections made on each double pancake. The superconducting magnet system has gone through a conceptual design review, and is in preliminary design started by the LLNL/MIT/PPPL collaboration. A number of changes have been made in the design since the conceptual design review, and are described in this paper. The majority of the design and all fabrication of the superconducting magnet system will be ,accomplished by industry, which will shortly be taking over the preliminary design. The magnet system is expected to be completed in early 2000

  10. Low noise niobium dc SQUID with a planar input coil

    Science.gov (United States)

    de Waal, V. J.; van den Hamer, P.; Klapwijk, T. M.

    1983-02-01

    A practical all-niobium dc superconducting quantum interference device (SQUID) with a niobium spiral input coil has been developed. The SQUID utilizes submicron Josephson junctions. The best intrinsic energy resolution obtained with a 1-nH SQUID is 4×10-32 J/Hz. A 20-turn 1.2-μH input coil is coupled to a 2.3-nH SQUID with an efficiency of 0.5. The energy resolution with respect to the coil is 1×10-30 J/Hz.

  11. Low noise niobium dc SQUID with a planar input coil

    Energy Technology Data Exchange (ETDEWEB)

    de Waal, V.J.; van den Hamer, P.; Klapwijk, T.M.

    1983-02-15

    A practical all-niobium dc superconducting quantum interference device (SQUID) with a niobium spiral input coil has been developed. The SQUID utilizes submicron Josephson junctions. The best intrinsic energy resolution obtained with a 1-nH SQUID is 4 x 10/sup -32/ J/Hz. A 20-turn 1.2-..mu..H input coil is coupled to a 2.3-nH SQUID with an efficiency of 0.5. The energy resolution with respect to the coil is 1 x 10/sup -30/ J/Hz.

  12. Development of superconducting wind turbine generators

    DEFF Research Database (Denmark)

    Jensen, Bogi Bech; Mijatovic, Nenad; Abrahamsen, Asger Bech

    2013-01-01

    In this paper, the commercial activities in the field of superconducting machines, particularly superconducting wind turbine generators, are reviewed and presented. Superconducting generators have the potential to provide a compact and light weight drive train at high torques and slow rotational...... speeds, because high magnetic fields can be produced by coils with very little loss. Three different superconducting wind turbine generator topologies have been proposed by three different companies. One is based on low temperature superconductors; one is based on high temperature superconductors......; and one is a fully superconducting generator based on MgB2. It is concluded that there is large commercial interest in superconducting machines, with an increasing patenting activity. Such generators are, however, not without their challenges. The superconductors have to be cooled down to somewhere...

  13. Development of Superconducting Wind Turbine Generators

    DEFF Research Database (Denmark)

    Jensen, Bogi Bech; Mijatovic, Nenad; Abrahamsen, Asger Bech

    2012-01-01

    In this paper the commercial activities in the field of superconducting machines, particularly superconducting wind turbine generators, are reviewed and presented. Superconducting generators have the potential to provide a compact and light weight drive train at high torques and slow rotational...... speeds, because high magnetic fields can be produced by coils with very little loss. Three different superconducting wind turbine generator topologies have been proposed by three different companies. One is based on low temperature superconductors (LTS); one is based on high temperature superconductors...... (HTS); and one is a fully superconducting generator based on MgB2. It is concluded that there is large commercial interest in superconducting machines, with an increasing patenting activity. Such generators are however not without their challenges. The superconductors have to be cooled down...

  14. Superconducting Accelerator Magnets

    CERN Document Server

    Mess, K H; Wolff, S

    1996-01-01

    The main topic of the book are the superconducting dipole and quadrupole magnets needed in high-energy accelerators and storage rings for protons, antiprotons or heavy ions. The basic principles of low-temperature superconductivity are outlined with special emphasis on the effects which are relevant for accelerator magnets. Properties and fabrication methods of practical superconductors are described. Analytical methods for field calculation and multipole expansion are presented for coils without and with iron yoke. The effect of yoke saturation and geometric distortions on field quality is studied. Persistent magnetization currents in the superconductor and eddy currents the copper part of the cable are analyzed in detail and their influence on field quality and magnet performance is investigated. Superconductor stability, quench origins and propagation and magnet protection are addressed. Some important concepts of accelerator physics are introduced which are needed to appreciate the demanding requirements ...

  15. Variable temperature superconducting microscope

    Science.gov (United States)

    Cheng, Bo; Yeh, W. J.

    2000-03-01

    We have developed and tested a promising type of superconducting quantum interference device (SQUID) microscope, which can be used to detect vortex motion and can operate in magnetic fields over a large temperature range. The system utilizes a single-loop coupling transformer, consisting of a patterned high Tc superconducting thin film. At one end of the transformer, a 20 μm diam detecting loop is placed close to the sample. At the other end, a large loop is coupled to a NbTi coil, which is connected to a low Tc SQUID sensor. Transformers in a variety of sizes have been tested and calibrated. The results show that the system is capable of detecting the motion of a single vortex. We have used the microscope to study the behavior of moving vortices at various positions in a YBa2Cu3O7 thin film bridge.

  16. NCSX Trim Coil Design

    International Nuclear Information System (INIS)

    Kalish, M.; Brooks, A.; Rushinski, J.; Upcavage, R.

    2009-01-01

    The National Compact Stellarator Experiment (NCSX) was being constructed at the Princeton Plasma Physics Laboratory in partnership with Oak Ridge National Laboratory before work was stopped in 2008. The objective of this experiment was to develop the stellarator concept and evaluate it's potential as a model for future fusion power plants. Stellarator design requires very precisely positioned Modular Coils of complex shape to form 3D plasmas. In the design of NCSX, Trim Coils were required to compensate for both the positioning of the coils during assembly and the fabrication tolerances of the Modular Coils. Use of the Trim Coils allowed for larger tolerances increasing ease of assembly and decreasing overall cost. A set of Trim coils was developed to suppress the toroidal flux in island regions due to misalignment, magnetic materials, and eddy currents. The requirement imposed upon the design forced the toroidal flux in island regions below 10% of the total toroidal flux in the plasma. An analysis was first performed to evaluate candidate Trim Coil configurations iterating both the size, number, and position of the coils. The design was optimized considering both performance and cost while staying within the tight restraints presented by the space limited geometry. The final design of the Trim Coils incorporated a 48 Coil top bottom symmetric set. Fabrication costs were minimized by having only two coil types and using a planar conventional design with off the shelf commercial conductor. The Trim Coil design incorporated supports made from simple structural shapes assembled together in a way which allowed for adjustment as well as accommodation for the tolerance build up on the mating surfaces. This paper will summarize the analysis that led to the optimization of the Trim Coils set, the trim coil mechanical design, thermal and stress analysis, and the design of the supporting Trim Coil structure

  17. A superconducting electron spectrometer

    International Nuclear Information System (INIS)

    Guttormsen, M.; Huebel, H.; Grumbkow, A. von

    1983-03-01

    The set-up and tests of an electron spectrometer for in-beam conversion electron measurements are described. A superconducting solenoid is used to transport the electrons from the target to cooled Si(Li) detectors. The solenoid is designed to produce either a homogeneous axially symmetric field of up to 2 Tesla or a variety of field profiles by powering the inner and outer set of coils of the solenoid separately. The electron trajectories resulting for various field profiles are discussed. In-beam electron spectra taken in coincidence with electrons, gammas and alpha-particles are shown. (Auth.)

  18. Letter report for the Superconducting Magnet Development Program, April 1, 1977--June 30, 1977

    International Nuclear Information System (INIS)

    Fietz, W.A.; Lubell, M.S.

    1977-11-01

    The results and accomplishments of the Superconducting Magnet Development Program (SCMDP) for the second quarter of the calendar year 1977 are summarized. The presentations are arranged according to projects rather than the group organization by discipline of the Magnetics and Superconductivity Section. The design, procurement, and fabrication of the Large Coil Segment are well under way. Significant progress is reported on the conductor stability and loss experiments for both toroidal field coils and poloidal field coils

  19. Applied superconductivity. Handbook on devices and applications. Vol. 1 and 2

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, Paul (ed.) [Jena Univ. (Germany). Inst. fuer Festkoerperphysik, AG Tieftemperaturphysik

    2015-07-01

    The both volumes contain the following 12 chapters: 1. Fundamentals; 2. Superconducting Materials; 3. Technology, Preparation, and Characterization (bulk materials, thin films, multilayers, wires, tapes; cooling); 4, Superconducting Magnets; 5. Power Applications (superconducting cables, superconducting current leads, fault current limiters, transformers, SMES and flywheels; rotating machines; SmartGrids); 6. Superconductive Passive Devices (superconducting microwave components; cavities for accelerators; superconducting pickup coils; magnetic shields); 7. Applications in Quantum Metrology (superconducting hot electron bolometers; transition edge sensors; SIS Mixers; superconducting photon detectors; applications at Terahertz frequency; detector readout); 8. Superconducting Radiation and Particle Detectors; 9. Superconducting Quantum Interference (SQUIDs); 10. Superconductor Digital Electronics; 11. Other Applications (Josephson arrays as radiation sources. Tunable microwave devices) and 12. Summary and Outlook (of the superconducting devices).

  20. Applied superconductivity. Handbook on devices and applications. Vol. 1 and 2

    International Nuclear Information System (INIS)

    Seidel, Paul

    2015-01-01

    The both volumes contain the following 12 chapters: 1. Fundamentals; 2. Superconducting Materials; 3. Technology, Preparation, and Characterization (bulk materials, thin films, multilayers, wires, tapes; cooling); 4, Superconducting Magnets; 5. Power Applications (superconducting cables, superconducting current leads, fault current limiters, transformers, SMES and flywheels; rotating machines; SmartGrids); 6. Superconductive Passive Devices (superconducting microwave components; cavities for accelerators; superconducting pickup coils; magnetic shields); 7. Applications in Quantum Metrology (superconducting hot electron bolometers; transition edge sensors; SIS Mixers; superconducting photon detectors; applications at Terahertz frequency; detector readout); 8. Superconducting Radiation and Particle Detectors; 9. Superconducting Quantum Interference (SQUIDs); 10. Superconductor Digital Electronics; 11. Other Applications (Josephson arrays as radiation sources. Tunable microwave devices) and 12. Summary and Outlook (of the superconducting devices).

  1. Application of superconductivity in cyclotron construction

    International Nuclear Information System (INIS)

    Blosser, H.G.

    1982-01-01

    This paper reviews major concepts and design features of the new class of cyclotrons which use superconducting coils to provide main magnet excitation. The discussion begins with a brief historical review tracing the evolution of these ''superconducting'' cyclotrons and the impact of this application of superconductivity in pushing back traditional cyclotron construction limits. This is followed by a review of the principal phenomena which come into play to set new limits on the operating regime, and the nature of these limits, some of which arise from orbit properties and some of which result from construction intricacies in the coil and in the rf system. Conclusions anticipate a future widely encompassing role in the application of superconductivity to cyclotron

  2. Superconductivity - applications

    International Nuclear Information System (INIS)

    The paper deals with the following subjects: 1) Electronics and high-frequency technology, 2) Superconductors for energy technology, 3) Superconducting magnets and their applications, 4) Electric machinery, 5) Superconducting cables. (WBU) [de

  3. Dual coil ignition system

    Energy Technology Data Exchange (ETDEWEB)

    Huberts, Garlan J.; Qu, Qiuping; Czekala, Michael Damian

    2017-03-28

    A dual coil ignition system is provided. The dual coil ignition system includes a first inductive ignition coil including a first primary winding and a first secondary winding, and a second inductive ignition coil including a second primary winding and a second secondary winding, the second secondary winding connected in series to the first secondary winding. The dual coil ignition system further includes a diode network including a first diode and a second diode connected between the first secondary winding and the second secondary winding.

  4. A superconductive electromagnet for nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Jelinek, J.; Srnka, A.; Studenik, J.

    1989-01-01

    The superconductive magnet includes at least three concentric frames mounted onto each other; they can be dismantled, or readjusted by axial or rotary motion. The frames carry the main coils and the inner and outer balancing coils. This arrangement offers a higher number of degrees of freedom for the calculation of the system geometry so as to attain the optimum magnetic field configuration. The design also allows the superconductive magnet to be operated at a liquid helium level depressed below the upper magnet plate. (J.B.). 1 fig

  5. Superconducting augmented rail gun (SARG)

    International Nuclear Information System (INIS)

    Homan, C.G.; Cummings, C.E.; Fowler, C.M.

    1986-01-01

    Superconducting augmentation consists of a superconducting coil operating in the persistent mode closely coupled magnetically with a normally conducting rail gun. A theoretical investigation of the effect of this system on a rail gun has shown that two benefits occur. Projectile velocities and launch efficiencies increase significantly depending on the magnetic coupling between the rail and augmentation circuits. Previous work evaluated an idealized system by neglecting energy dissipation effects. In this paper, the authors extend the analysis to include the neglected terms and show improved actual launch efficiencies for the SARG configuration. In this paper, the authors discuss details of projectile design in depth and present preliminary results of rail gun performance

  6. Progress on axicell MFTF-B superconducting magnet systems

    International Nuclear Information System (INIS)

    Wang, S.T.; Kozman, T.A.; Hanson, C.L.; Shimer, D.W.; VanSant, J.H.; Zbasnik, J.

    1983-01-01

    Since the entire Mirror Fusion Test Facility (MFTF-B) Magnet System was reconfigured from the original A-cell to an axicell design, much progress has been made on the design, fabrication, and installation planning. The axicell MFTF-B magnet array consists of a total of 26 large superconducting main coils. This paper provides an engineering overview of the progress of these coils. Recent studies on the effects of field errors on the plasma at the recircularizing region (transition coils) show that small field errors will generate large displacements of the field lines. These field errors might enhance radial electron heat transport and deteriorate the plasma confinement. Therefore, 16 superconducting trim coils have been designed to correct the coil misalignments. Progress of the trim coils are reported also

  7. ITER central solenoid model coil heat treatment complete and assembly started

    International Nuclear Information System (INIS)

    Thome, R.J.; Okuno, K.

    1998-01-01

    A major R and D task in the ITER program is to fabricate a Superconducting Model Coil for the Central Solenoid to establish the design and fabrication methods for ITER size coils and to demonstrate conductor performance. Completion of its components is expected in 1998, to be followed by assembly with structural components and testing in a facility at JAERI

  8. Biomaterials Made from Coiled-Coil Peptides.

    Science.gov (United States)

    Conticello, Vincent; Hughes, Spencer; Modlin, Charles

    The development of biomaterials designed for specific applications is an important objective in personalized medicine. While the breadth and prominence of biomaterials have increased exponentially over the past decades, critical challenges remain to be addressed, particularly in the development of biomaterials that exhibit highly specific functions. These functional properties are often encoded within the molecular structure of the component molecules. Proteins, as a consequence of their structural specificity, represent useful substrates for the construction of functional biomaterials through rational design. This chapter provides an in-depth survey of biomaterials constructed from coiled-coils, one of the best-understood protein structural motifs. We discuss the utility of this structurally diverse and functionally tunable class of proteins for the creation of novel biomaterials. This discussion illustrates the progress that has been made in the development of coiled-coil biomaterials by showcasing studies that bridge the gap between the academic science and potential technological impact.

  9. Study of a 5-Tesla large aperture coil for the CLIC detector

    CERN Document Server

    Cure, B

    2011-01-01

    The present design of a CLIC detector foresees a large solenoid magnet with a 6 m aperture and a magnetic induction of 5 T at the interaction point. This can be achieved by a thin superconducting coil. This report gives the typical main parameters of such a coil and presents the feasibility based on and compared with the CMS and Atlas solenoid coil designs, indicating the limits on the conductor and the identified R&D prospects.

  10. Development of superconducting magnets for the Canadian electrodynamic Maglev vehicle

    International Nuclear Information System (INIS)

    Fife, A.A.; Ensing, H.J.; Tillotson, M.; Westera, W.

    1986-01-01

    A review is presented on the current status of superconducting magnet developments for the Canadian electrodynamic Maglev transportation system. Various design aspects of the levitation and linear synchronous motor magnets, appropriate for the current vehicle concepts, are discussed. In addition, recent experimental work is outlined on the development of a suitable epoxy impregnation technology for the superconducting coils

  11. Reviews of large superconducting machines: Metallurgy, fabrication, and applications

    International Nuclear Information System (INIS)

    Bogner, G.

    1981-01-01

    This paper reviews large superconducting machines presently in place or in experiment. The ''Cello'' particle detector magnet for the positron-electron colliding beam facility PETRA at DESY in Hamburg is shown, and the Fermi Lab, and the Brookhaven ISABELLE also described. Electrodynamic levitation systems are specified, as researched and developed in Germany and Japan. Of superconducting coils for magnetic separation, a high gradient magnetic separator with superconducting magnet and steel wool, and a Jones type high gradient magnetic separator are schematicized. Turbogenerators with superconductor field winding are studied. Superconducting high power cables include the flexible coaxial cable core consisting of a perforated polyethylene tube and test cables at Siemens and at Brookhaven. Magnet systems for fusion reactors include tokamaks and tandem mirrors, and the toroidal coil experiment at Oak Ridge National Laboratory is described, among others. Superconducting magnets for MHD plants, and superconducting magnet energy storage (SME storage) are also discussed

  12. Design and AC loss analysis of a superconducting synchronous motor

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Q [Cambridge University Engineering Department, Trumpington Street, Cambridge CB2 1PZ (United Kingdom); Majoros, M [Department of Materials Science and Engineering, Ohio State University (United States); Hong, Z [Cambridge University Engineering Department, Trumpington Street, Cambridge CB2 1PZ (United Kingdom); Campbell, A M [Cambridge University Engineering Department, Trumpington Street, Cambridge CB2 1PZ (United Kingdom); Coombs, T A [Cambridge University Engineering Department, Trumpington Street, Cambridge CB2 1PZ (United Kingdom)

    2006-11-15

    This paper gives a conceptual design of a superconducting synchronous motor consisting of both high-temperature superconducting rotating field winding and armature winding. The AC losses of the armature winding of the motor have been investigated experimentally and numerically, by considering the self-field of the superconducting coils and the rotating magnetic field exposed on the armature winding. The recent developments of YBCO-coated conductors present the possibility of achieving a wholly superconducting machine of significantly smaller size and weight than a conventional machine. Both the rotating field winding and the armature winding are composed of YBCO high-temperature superconducting (HTS) coils. A low AC loss armature winding design has been developed for this superconducting synchronous motor. The performance of the machine was investigated by modelling with the finite-element method. The machine's torque is calculated from first principles by considering the angle between the field and the armature main flux lines.

  13. Quench detector for large pulsed coils and quench analysis for the LASL/Westinghouse 20 MJ coil

    International Nuclear Information System (INIS)

    Hennessy, M.J.; Heintz, A.W.; Eckels, P.W.

    1981-01-01

    A detection scheme has been devised for use in the test of the 20 Mj Induction Heating Coil. This scheme allows the sensing of plus or minus voltages less than 320 mv resistive in magnitude in coils which will have inductive voltage components as high as /plus or minus/2.5 kv. The network which achieves this sensitivity is stable to less than 12.8 ppm. This method adopted involves the bucking out of the inductive voltage with two secondary co-wound flux sensing coils tapped at locations adjacent to voltage taps in the main superconducting coil. The detection scheme is recommended if large ripple or control voltages exist subsequent to the coil pulse. The most severe event which might quench the coil and/or damage the winding is exposure of the coil to gaseous cooling through lack of proper liquid level control. The detection scheme will protect the coil against this and other abnormal conditions that could damage the coil

  14. Development of Ground Coils with Low Eddy Current Loss by Applying the Compression Molding Method after the Coil Winding

    Science.gov (United States)

    Suzuki, Masao; Aiba, Masayuki; Takahashi, Noriyuki; Ota, Satoru; Okada, Shigenori

    In a magnetically levitated transportation (MAGLEV) system, a huge number of ground coils will be required because they must be laid for the whole line. Therefore, stable performance and reduced cost are essential requirements for the ground coil development. On the other hand, because the magnetic field changes when the superconducting magnet passes by, an eddy current will be generated in the conductor of the ground coil and will result in energy loss. The loss not only increases the magnetic resistance for the train running but also brings an increase in the ground coil temperature. Therefore, the reduction of the eddy current loss is extremely important. This study examined ground coils in which both the eddy current loss and temperature increase were small. Furthermore, quantitative comparison for the eddy current loss of various magnet wire samples was performed by bench test. On the basis of the comparison, a round twisted wire having low eddy current loss was selected as an effective ground coil material. In addition, the ground coils were manufactured on trial. A favorable outlook to improve the size accuracy of the winding coil and uneven thickness of molded resin was obtained without reducing the insulation strength between the coil layers by applying a compression molding after winding.

  15. Completion of the ITER central solenoid model coils installation

    International Nuclear Information System (INIS)

    Tsuji, H.

    1999-01-01

    The short article details how dozens of problems, regarding the central solenoid model coils installation, were faced and successfully overcome one by one at JAERI-Naga. A black and white photograph shows K. Kwano, a staff member of the JAERI superconducting magnet laboratory, to be still inside the vacuum tank while the lid is already being brought down..

  16. Upgrade of DC power supply system in ITER CS model coil test facility

    International Nuclear Information System (INIS)

    Shimono, Mitsugu; Uno, Yasuhiro; Yamazaki, Keita; Kawano, Katsumi; Isono, Takaaki

    2014-03-01

    Objective of the ITER CS Model Coil Test Facility is to evaluate a large scale superconducting conductor for fusion using the Central Solenoid (CS) Model Coil, which can generate a 13T magnetic field in the inner bore with a 1.5 m diameter. The facility is composed of a helium refrigerator / liquefier system, a DC power supply system, a vacuum system and a data acquisition system. The DC power supply system supplies currents to two superconducting coils, the CS Model Coil and an insert coil. A 50-kA DC power supply is installed for the CS Model Coil and two 30 kA DC power supplies are installed for an insert coil. In order to evaluate superconducting performance of a conductor used for ITER Toroidal Field (TF) coils whose operating current is 68 kA, the line for an insert coil is upgraded. A 10 kA DC power supply was added, DC circuit breakers were upgraded, bus bars and current measuring instrument were replaced. In accordance to the upgrade, operation manual was revised. (author)

  17. Development of a superconducting claw-pole motor

    International Nuclear Information System (INIS)

    Watanabe, E.; Kikukawa, K.; Satoh, Y.; Torii, S.

    2008-01-01

    We have developed and produced a superconducting claw-pole motor for a trial purpose as a method to make the best use of the characteristic of superconductivity without collector rings or rotating superconducting coils that need to be cryocooled, and made some examinations. The unique feature in this motor is to have the mechanism that supports the reaction magnetic force generated in the axial direction

  18. Magnetic design of a FFAG superconducting magnet

    International Nuclear Information System (INIS)

    Obana, T.; Ogitsu, T.; Nakamoto, T.; Sasaki, K.; Yamamoto, A.; Yoshimoto, M.; Mori, Y.; Orikasa, T.

    2005-01-01

    A superconducting magnet for a Fixed Field Alternating Gradient (FFAG) accelerator has been proposed. The required magnetic field is static and proportional to the k-th power of the orbit radius where k is the geometrical field index of the accelerator. In 2D, the required magnetic field can be generated with the optimized cross section of the coil. The cross section of the coils is a left-right asymmetry to simplify the cross section and ellipse to downsize the magnet. Local and integral 3D fields along the beam trajectory are evaluated with using new type of 3D coil configuration

  19. BNL Direct Wind Superconducting Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Parker, B.; Anerella, M.; Escallier, J.; Ghosh, A.; Jain, A.; Marone, A.; Muratore, A.; Wanderer, P.

    2011-09-12

    BNL developed Direct Wind magnet technology is used to create a variety of complex multi-functional multi-layer superconducting coil structures without the need for creating custom production tooling and fixturing for each new project. Our Direct Wind process naturally integrates prestress into the coil structure so external coil collars and yokes are not needed; the final coil package transverse size can then be very compact. Direct Wind magnets are produced with very good field quality via corrections applied during the course of coil winding. The HERA-II and BEPC-II Interaction Region (IR) magnet, J-PARC corrector and Alpha antihydrogen magnetic trap magnets and our BTeV corrector magnet design are discussed here along with a full length ILC IR prototype magnet presently in production and the coils that were wound for an ATF2 upgrade at KEK. A new IR septum magnet design concept for a 6.2 T combined-function IR magnet for eRHIC, a future RHIC upgrade, is introduced here.

  20. Thermal results of the Japanese LCT coil's domestic test

    International Nuclear Information System (INIS)

    Tada, Eisuke; Hiyama, Tadao; Kato, Takashi; Takahashi, Osamu; Shimamoto, Susumu

    1984-01-01

    This paper describes thermal results obtained in the domestic test of the Japanese LCT coil which was constructed at the Japan Atomic Energy Research Institute (JAERI) in order to develop large superconducting coils for fusion in international collaboration proposed by the IEA. The domestic test was carried out from May 13 to June 17 in 1982 by using the test facility named as SETF (Superconducting Engineering Test Facility) which was composed of a 350-l/h helium cryogenic system, a vacuum system, a 30 KA-DC power supply and protection system, and a PDP-11/70 computer system. The cool-down characteristics, heat load, fast discharge characteristics, stability, and warm-up characteristics of the LCT coil were successfully measured in the test. The details of thermal test results acquired in the cool-down, heat load measurement, fast discharge, and warm-up, and the comparison between measurements and calculations are described in this paper. (author)