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Sample records for transmission line magnet

  1. ANALYSIS AND SIMULATION OF MAIN MAGNET TRANSMISSION LINE EFFECT

    Energy Technology Data Exchange (ETDEWEB)

    ZHANG,W.; MARNERIS, I.; SANDBERG, J.

    2007-06-25

    A main magnet chain forms a pair of transmission lines. Pulse-reflection-caused voltage and current differentiation throughout the magnet chain can have adverse effect on main magnet field quality. This effect is associated with magnet system configuration, coupling efficiency, and parasitic parameters. A better understanding of this phenomenon will help us in new design and existing system upgrade. In this paper, we exam the transmission line effect due to different input functions as well as configuration, coupling, and other parameters.

  2. Tailoring of electron flow current in magnetically insulated transmission lines

    Directory of Open Access Journals (Sweden)

    J. P. Martin

    2009-03-01

    Full Text Available It is desirable to optimize (minimizing both the inductance and electron flow the magnetically insulated vacuum sections of low impedance pulsed-power drivers. The goal of low inductance is understandable from basic efficiency arguments. The goal of low electron flow results from two observations: (1 flowing electrons generally do not deliver energy to (or even reach most loads, and thus constitute a loss mechanism; (2 energetic electrons deposited in a small area can cause anode damage and anode plasma formation. Low inductance and low electron flow are competing goals; an optimized system requires a balance of the two. While magnetically insulated systems are generally forgiving, there are times when optimization is crucial. For example, in large pulsed-power drivers used to energize high energy density physics loads, the electron flow as a fraction of total current is small, but that flow often reaches the anode in relatively small regions. If the anode temperature becomes high enough to desorb gas, the resulting plasma initiates a gap closure process that can impact system performance. Magnetic-pressure driven (z pinches and material equation of state loads behave like a fixed inductor for much of the drive pulse. It is clear that neither fixed gap nor constant-impedance transmission lines are optimal for driving inductive loads. This work shows a technique for developing the optimal impedance profile for the magnetically insulated section of a high-current driver. Particle-in-cell calculations are used to validate the impedance profiles developed in a radial disk magnetically insulated transmission line geometry. The input parameters are the spacing and location of the minimum gap, the effective load inductance, and the desired electron flow profile. The radial electron flow profiles from these simulations are in good agreement with theoretical predictions when driven at relatively high voltage (i.e., V≥2  MV.

  3. Requirements for self-magnetically insulated transmission lines

    Directory of Open Access Journals (Sweden)

    J. Pace VanDevender

    2015-03-01

    Full Text Available Self-magnetically insulated transmission lines (MITLs connect pulsed-power drivers with a load. Although the technology was originally developed in the 1970s and is widely used today in super power generators, failure of the technology is the principal limitation on the power that can be delivered to an experiment. We address issues that are often overlooked, rejected after inadequate simulations, or covered by overly conservative assumptions: (i electron retrapping in coupling MITLs to loads, (ii the applicability of collisionless versus collisional electron flow, (iii power transport efficiency as a function of the geometry at the beginning of the MITL, (iv gap closure and when gap closure can be neglected, and (v the role of negative ions in causing anode plasmas and enhancing current losses. We suggest a practical set of conservative design requirements for self-magnetically insulated electron flow based on the results discussed in this paper and on previously published results. The requirements are not necessarily severe constraints in all MITL applications; however, each of the 18 suggested requirements should be examined in the design of a MITL and in the investigation of excessive losses.

  4. Lightning Current Observation on UHVAC Transmission Lines by Improved Magnetic Steel Rod Method

    Directory of Open Access Journals (Sweden)

    Anfeng Jiang

    2014-09-01

    Full Text Available Lightning stroke is the main threaten to the safe operation of UHVAC transmission lines. The magnetic steel rod method had been widely used as a traditional method for lightning accident and lightning current investigation in high voltage transmission lines. For the application of the magnetic steel rod method on UHVAC transmission lines, this paper proposed a practical and easy improved method of installing the magnetic steel rods directly on the transmission towers. The residual magnetism curve and accuracy verification of the proposed method was obtained through complex steel structure impulse current experiments. The magnetic steel rod location on UHVAC transmission tower was analyzed by the numerical analysis software MagNet. The application results of the proposed method on the first demonstration and test UHVAC transmission line is presented. The obtained datasets after one storm season was analyzed through Electromagnetic Transients Program. It is shown that the proposed method is feasible.

  5. Recent progress of the improved magnetically insulated transmission line oscillator.

    Science.gov (United States)

    Fan, Yu-Wei; Zhong, Hui-Huang; Li, Zhi-Qiang; Shu, Ting; Zhang, Jian-De; Liu, Jin-Liang; Yang, Jian-Hua; Zhang, Jun; Yuan, Cheng-Wei; Luo, Ling

    2008-03-01

    The improved magnetically insulated transmission line oscillator (MILO) is a gigawatt-class L-band high power microwave tube driven by a 550 kV, 57 kA, 50 ns electron beam. It has allowed us to generate 2.4 GW pulse of 22 ns duration. The recent progress of the improved MILO is presented in this paper. First, a field shaper cathode is introduced into the improved MILO to avoid the cathode flares in the triple point region. The experimental results show that the cathode flares are avoided, so the lifetime of the velvet cathode is longer than that of the taper cathode. Furthermore, the shot-to-shot reproducibility is better than that of the taper cathode. Second, In order to prolong the pulse duration and increase the radiated microwave power, a self-built 600 kV, 10 Omega, 80 ns pulser: SPARK-03 is employed to drive the improved MILO. Simulation and experimental investigation are performed. In simulation, when the improved MILO is driven by a 600 kV, 57 kA electron beam, high-power microwave is generated with output power of 4.15 GW, frequency of 1.76 GHz, and relevant power conversion efficiency of 12.0%. In experiments, when the diode voltage is 550 kV and current is 54 kA, the measured results are that the radiated microwave power is above 3.1 GW, the pulse duration is above 40 ns, the microwave frequency is about 1.755 GHz, and the power conversion efficiency is about 10.4%.

  6. Millimeter-Gap Magnetically Insulated Transmission Line Power Flow Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Hutsel, Brian Thomas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stoltzfus, Brian S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Fowler, William E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); LeChien, Keith R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mazarakis, Michael G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Moore, James K. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mulville, Thomas D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Savage, Mark E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stygar, William A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); McKenney, John L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jones, Peter A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); MacRunnels, Diego J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Long, Finis W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Porter, John L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-09-01

    An experiment platform has been designed to study vacuum power flow in magnetically insulated transmission lines (MITLs). The platform was driven by the 400-GW Mykonos-V accelerator. The experiments conducted quantify the current loss in a millimeter-gap MITL with respect to vacuum conditions in the MITL for two different gap distances, 1.0 and 1.3 mm. The current loss for each gap was measured for three different vacuum pump down times. As a ride along experiment, multiple shots were conducted with each set of hardware to determine if there was a conditioning effect to increase current delivery on subsequent shots. The experiment results revealed large differences in performance for the 1.0 and 1.3 mm gaps. The 1.0 mm gap resulted in current loss of 40%-60% of peak current. The 1.3 mm gap resulted in current losses of less than 5% of peak current. Classical MITL models that neglect plasma expansion predict that there should be zero current loss, after magnetic insulation is established, for both of these gaps. The experiments result s indicate that the vacuum pressure or pump down time did not have a significant effect on the measured current loss at vacuum pressures between 1e-4 and 1e-5 Torr. Additionally, there was not repeatable evidence of a conditioning effect that reduced current loss for subsequent full-energy shots on a given set of hardware. It should be noted that the experiments conducted likely did not have large loss contributions due to ion emission from the anode due to the relatively small current densi-ties (25-40 kA/cm) in the MITL that limited the anode temperature rise due to ohmic heating. The results and conclusions from these experiments may have limited applicability to MITLs of high current density (>400 kA/cm) used in the convolute and load region of the Z which experience temperature increases of >400° C and generate ion emission from anode surfaces.

  7. Design considerations of transmission line superconductors for fast-cycling accelerator magnets

    International Nuclear Information System (INIS)

    Piekarz, H.; Fermilab

    2008-01-01

    Novel design options of HTS and LTS superconductor lines for fast-cycling accelerator magnets are presented. The cryogenic power losses in using these conductors in transmission line application to energize the accelerator magnet string are discussed. A test arrangement to measure power loss of the proposed superconductor lines operating up to 2 T/s ramp rate and 0.5 Hz repetition cycle is described

  8. Design of a 2 Tesla transmission line magnet for the VLHC

    CERN Document Server

    Foster, G W; Novitski, I

    2000-01-01

    A prototype of the transmission line magnet for the Very Large Hadron Collider is being designed at Fermilab. This is a single-turn warm iron superconducting magnet in a "Double-C" configuration. Iron poles form a high quality alternating-gradient magnet field in two 20 mm height beam gaps. Simple magnet construction and manufacturing processes and a room temperature iron yoke give a significant reduction in magnet cost. Open beam gaps simplify magnetic measurements and vacuum chamber installation. The magnet mechanical stability was investigated for several mechanical models. A high field quality over the whole range (0.1 T-2.0 T) of field variation was calculated using correcting holes in the iron poles. The magnet optimization was carried out by POISSON, OPERA 2D and ANSYS codes. The results of magnet design and model tests are presented. (6 refs).

  9. Magnetic force on the walls of a square coaxial transmission line

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Lili, E-mail: zg207@126.com; Zhao, Dekui

    2013-10-15

    There is magnetic force acting on the wall of a square coaxial transmission line when TEM wave propagates in it. The self-inductance can be determined based on a conformal transformation for the field region, which demonstrates that the inductance only depends on the side length ratio of the two walls instead of the length of the walls. The magnetic force on each side of the walls is then calculated by employing the principle of virtual work. It is proved that the magnetic force has the same magnitude and opposite direction to the electric force. And then the electromagnetic force on the wall is zero. The general meaning of this conclusion for all kinds of coaxial transmission line is proposed. - Highlights: • The self-inductance of square coaxial transmission line is determined. • The inductance only depends on the side length ratio of the two walls. • The magnetic force on each side of the walls is calculated. • The electromagnetic force on wall is zero. • The conclusion has general meaning for all kinds of coaxial transmission line.

  10. Magnetic force on the walls of a square coaxial transmission line

    Science.gov (United States)

    Gao, Lili; Zhao, Dekui

    2013-10-01

    There is magnetic force acting on the wall of a square coaxial transmission line when TEM wave propagates in it. The self-inductance can be determined based on a conformal transformation for the field region, which demonstrates that the inductance only depends on the side length ratio of the two walls instead of the length of the walls. The magnetic force on each side of the walls is then calculated by employing the principle of virtual work. It is proved that the magnetic force has the same magnitude and opposite direction to the electric force. And then the electromagnetic force on the wall is zero. The general meaning of this conclusion for all kinds of coaxial transmission line is proposed.

  11. Study of electric and magnetic fields on transmission lines using a computer simulation program

    International Nuclear Information System (INIS)

    Robelo Mojica, Nelson

    2011-01-01

    A study was conducted to determine and reduce levels of electric and magnetic fields with different configurations used by the Instituto Costarricense de Electricidad in power transmission lines in Costa Rica. The computer simulation program PLS-CADD with EPRI algorithm has been used to obtain field values close to those actual to lines easements that have worked to date. Different configurations have been compared on equal terms and the lowest levels of electric and magnetic fields are determined. The most appropriate configuration of the tower has been obtained and therefore has decreased exposure to electromagnetic fields people, without affecting the energy demand of the population. (author) [es

  12. Influence of nonuniform external magnetic fields and anode--cathode shaping on magnetic insulation in coaxial transmission lines

    International Nuclear Information System (INIS)

    Mostrom, M.A.

    1979-01-01

    Coaxial transmission lines, used to transfer the high voltage pulse into the diode region of a relativistic electron beam generator, have been studied using the two-dimensional time-dependent fully relativistic and electromagnetic particle simulation code CCUBE. A simple theory of magnetic insulation that agrees well with simulation results for a straight cylindrical coax in a uniform external magnetic field is used to interpret the effects of anode--cathode shaping and nonuniform external magnetic fields. Loss of magnetic insulation appears to be minimized by satisfying two conditions: (1) the cathode surface should follow a flux surface of the external magnetic field; (2) the anode should then be shaped to insure that the magnetic insulation impedance, including transients, is always greater than the effective load impedance wherever there is an electron flow in the anode--cathode gap

  13. Method and apparatus for magnetic resonance imaging and spectroscopy using microstrip transmission line coils

    Science.gov (United States)

    Zhang, Xiaoliang; Ugurbil, Kamil; Chen, Wei

    2006-04-04

    Apparatus and method for MRI imaging using a coil constructed of microstrip transmission line (MTL coil) are disclosed. In one method, a target is positioned to be imaged within the field of a main magnetic field of a magnet resonance imaging (MRI) system, a MTL coil is positioned proximate the target, and a MRI image is obtained using the main magnet and the MTL coil. In another embodiment, the MRI coil is used for spectroscopy. MRI imaging and spectroscopy coils are formed using microstrip transmission line. These MTL coils have the advantageous property of good performance while occupying a relatively small space, thus allowing MTL coils to be used inside restricted areas more easily than some other prior art coils. In addition, the MTL coils are relatively simple to construct of inexpensive components and thus relatively inexpensive compared to other designs. Further, the MTL coils of the present invention can be readily formed in a wide variety of coil configurations, and used in a wide variety of ways. Further, while the MTL coils of the present invention work well at high field strengths and frequencies, they also work at low frequencies and in low field strengths as well.

  14. Cryogenic Fiber Optic Sensors for Superconducting Magnets and Power Transmission Lines in High Energy Physics Applications

    CERN Document Server

    AUTHOR|(CDS)2081689; Bajko, Marta

    In the framework of the Luminosity upgrade of the Large Hadron Collider (HL - LHC), a remarkable R&D effort is now ongoing at the European Organization for Nuclear Research (CERN) in order to develop a new generation of accelerator magnets and superconducting power transmission lines. The magnet technology will be based on Nb$_{3}$Sn enabling to operate in the 11 - 13 T range. In parallel, in order to preserve the power converters from the increasing radiation level, high power transmission lines are foreseen to feed the magnets from free - radiation zones. These will be based on high temperature superconductors cooled down with helium gas in the range 5 - 30 K. The new technologies will require advanced design and fabrication approaches as well as adapted instrumentation for monitoring both the R&D phase and operation. Resistive sensors have been used so far for voltage, temperature and strain monitoring but their integration still suffers from the number of electrical wires and the complex compensat...

  15. Environmental and health effects of electric and magnetic fields from transmission lines

    International Nuclear Information System (INIS)

    Cronly, B.

    1995-01-01

    The paper outlines the underlying physical mechanisms by which electric and magnetic fields exist, with particular reference to high voltage transmission lines. Epidemiological and laboratory studies are the two approaches used in research into the subject and the shortcomings and inconstancies in the results are mentioned. Recent epidemiological results are presented together with possible mechanisms between fields and the human body. Attention is drawn to the work of certain international and national bodies concerning the alleged association between electromagnetic fields and ill-health, and their conclusions are reported. Finally, the policy of the Electricity Supply Board in Ireland is outlined. 2 figs

  16. Numerical simulation of cathode plasma dynamics in magnetically insulated vacuum transmission lines

    International Nuclear Information System (INIS)

    Thoma, C.; Genoni, T. C.; Welch, D. R.; Rose, D. V.; Clark, R. E.; Miller, C. L.; Stygar, W. A.; Kiefer, M. L.

    2015-01-01

    A novel algorithm for the simulation of cathode plasmas in particle-in-cell codes is described and applied to investigate cathode plasma evolution in magnetically insulated transmission lines (MITLs). The MITL electron sheath is modeled by a fully kinetic electron species. Electron and ion macroparticles, both modeled as fluid species, form a dense plasma which is initially localized at the cathode surface. Energetic plasma electron particles can be converted to kinetic electrons to resupply the electron flux at the plasma edge (the “effective” cathode). Using this model, we compare results for the time evolution of the cathode plasma and MITL electron flow with a simplified (isothermal) diffusion model. Simulations in 1D show a slow diffusive expansion of the plasma from the cathode surface. But in multiple dimensions, the plasma can expand much more rapidly due to anomalous diffusion caused by an instability due to the strong coupling of a transverse magnetic mode in the electron sheath with the expanding resistive plasma layer

  17. Application of magnetically insulated transmission lines for high current, high voltage electron beam accelerators

    International Nuclear Information System (INIS)

    Shope, S.L.; Mazarakis, M.G.; Frost, C.A.; Poukey, J.W.; Turman, B.N.

    1993-01-01

    Self Magnetically Insulated Transmission Lines (MITL) adders have been used successfully in a number of Sandia accelerators such as HELIA, HERMES III, and SABRE. Most recently the authors used a MITL adder in the RADLAC/SMILE electron beam accelerator to produce high quality, small radius (r b < 2 cm), 11 to 15 MeV, 50 to 100-kA beams with a small transverse velocity v perpendicular/c = β perpendicular ≤ 0.1. In RADLAC/SMILE, a coaxial MITL passed through the eight, 2 MV vacuum envelopes. The MITL summed the voltages of all eight feeds to a single foilless diode. The experimental results are in good agreement with code simulations. The authors' success with the MITL technology led them to investigate the application to higher energy accelerator designs. They have a conceptual design for a cavity-fed MITL that sums the voltages from 100 identical, inductively-isolated cavities. Each cavity is a toroidal structure that is driven simultaneously by four 8-ohm pulse-forming lines, providing a 1-MV voltage pulse to each of the 100 cavities. The point design accelerator is 100 MV, 500 kA, with a 30-50-ns FWHM output pulse

  18. Application of Magnetically Insulated Transmission Lines for high current, high voltage electron beam accelerators

    International Nuclear Information System (INIS)

    Shope, S.L.; Mazarakis, M.G.; Frost, C.A.; Poukey, J.W.; Turman, B.N.

    1991-01-01

    Self Magnetically Insulated Transmission Lines (MITL) adders have been used successfully in a number of Sandia accelerators such as HELIA, HERMES III, and SABRE. Most recently we used at MITL adder in the RADLAC/SMILE electron beam accelerator to produce high quality, small radius (r ρ < 2 cm), 11 to 15 MeV, 50 to 100-kA beams with a small transverse velocity v perpendicular/c = β perpendicular ≤ 0.1. In RADLAC/SMILE, a coaxial MITL passed through the eight, 2 MV vacuum envelopes. The MITL summed the voltages of all eight feeds to a single foilless diode. The experimental results are in good agreement with code simulations. Our success with the MITL technology led us to investigate the application to higher energy accelerator designs. We have a conceptual design for a cavity-fed MITL that sums the voltages from 100 identical, inductively-isolated cavities. Each cavity is a toroidal structure that is driven simultaneously by four 8-ohm pulse-forming lines, providing a 1-MV voltage pulse to each of the 100 cavities. The point design accelerator is 100 MV, 500 kA, with a 30--50 ns FWHM output pulse. 10 refs

  19. Coupling of an applied field magnetically insulated ion diode to a high power magnetically insulated transmission line system

    International Nuclear Information System (INIS)

    Maenchen, J.E.

    1983-01-01

    The coupling of energy from a high power pulsed accelerator through a long triplate magnetically insulated transmission line (MITL) in vacuum to an annular applied magnetic field insulated extraction ion diode is examined. The narrow power transport window and the wave front erosion of the MITL set stringent impedance history conditions on the diode load. A new ion diode design developed to satisfy these criteria with marginal electron insulation is presented. The LION accelerator is used to provide a positive polarity 1.5 MV, 350 kA, 40 ns FWHM pulse with a 30 kA/ns current rate from a triplate MITL source. A transition converts the triplate into a cylindrical cross section which flares into the ion diode load. Extensive current and voltage measurements performed along this structure and on the extracted ion beam provide conclusive evidence that the self insulation condition of the MITL is maintained in the transition by current loss alone. The ion diode utilizes a radial magnetic field between a grounded cathode annular emission tip and a disk anode. A 50 cm 2 dielectric/metal anode area serves as the ion plasma source subject to direct electron bombardment from the opposing cathode tip under marginal magnetic insulation conditions. The ions extracted cross the radial magnetic field and exit the diode volume as an annular cross section beam of peak current about 100 kA. The diode current gradually converts from the initial electron flow to nearly 100% ion current after 30 ns, coupling 60% of the diode energy into ions

  20. A Ku-band magnetically insulated transmission line oscillator with overmoded slow-wave-structure

    Science.gov (United States)

    Jiang, Tao; He, Jun-Tao; Zhang, Jian-De; Li, Zhi-Qiang; Ling, Jun-Pu

    2016-12-01

    In order to enhance the power capacity, an improved Ku-band magnetically insulated transmission line oscillator (MILO) with overmoded slow-wave-structure (SWS) is proposed and investigated numerically and experimentally. The analysis of the dispersion relationship and the resonant curve of the cold test indicate that the device can operate at the near π mode of the TM01 mode, which is useful for mode selection and control. In the particle simulation, the improved Ku-band MILO generates a microwave with a power of 1.5 GW and a frequency of 12.3 GHz under an input voltage of 480 kV and input current of 42 kA. Finally, experimental investigation of the improved Ku-band MILO is carried out. A high-power microwave (HPM) with an average power of 800 MW, a frequency of 12.35 GHz, and pulse width of 35 ns is generated under a diode voltage of 500 kV and beam current of 43 kA. The consistency between the experimental and simulated far-field radiation pattern confirms that the operating mode of the improved Ku-band MILO is well controlled in π mode of the TM01 mode. Project supported partly by the National Natural Science Foundation of China (Grant No. 61171021).

  1. 55-TW magnetically insulated transmission-line system: Design, simulations, and performance

    Directory of Open Access Journals (Sweden)

    W. A. Stygar

    2009-12-01

    Full Text Available We describe herein a system of self-magnetically insulated vacuum transmission lines (MITLs that operated successfully at 20 MA, 3 MV, and 55 TW. The system delivered the electromagnetic-power pulse generated by the Z accelerator to a physics-package load on over 1700 Z shots. The system included four levels that were electrically in parallel. Each level consisted of a water flare, vacuum-insulator stack, vacuum flare, and 1.3-m-radius conical outer MITL. The outputs of the four outer MITLs were connected in parallel by a 7.6-cm-radius 12-post double-post-hole vacuum convolute. The convolute added the currents of the four outer MITLs, and delivered the combined current to a single 6-cm-long inner MITL. The inner MITL delivered the current to the load. The total initial inductance of the stack-MITL system was 11 nH. A 300-element transmission-line-circuit model of the system has been developed using the tl code. The model accounts for the following: (i impedance and electrical length of each of the 300 circuit elements, (ii electron emission from MITL-cathode surfaces wherever the electric field has previously exceeded a constant threshold value, (iii Child-Langmuir electron loss in the MITLs before magnetic insulation is established, (iv MITL-flow-electron loss after insulation, assuming either collisionless or collisional electron flow, (v MITL-gap closure, (vi energy loss to MITL conductors operated at high lineal current densities, (vii time-dependent self-consistent inductance of an imploding z-pinch load, and (viii load resistance, which is assumed to be constant. Simulations performed with the tl model demonstrate that the nominal geometric outer-MITL-system impedance that optimizes overall performance is a factor of ∼3 greater than the convolute-load impedance, which is consistent with an analytic model of an idealized MITL-load system. Power-flow measurements demonstrate that, until peak current, the Z stack-MITL system

  2. A long-pulse repetitive operation magnetically insulated transmission line oscillator.

    Science.gov (United States)

    Fan, Yu-Wei; Zhong, Hui-Huang; Zhang, Jian-De; Shu, Ting; Liu, Jin Liang

    2014-05-01

    The improved magnetically insulated transmission line oscillator (MILO) is a gigawatt-class L-band high power microwave tube. It has allowed us to generate 3.1 GW pulse of 40 ns duration in the single-pulse operation and 500 MW pulse of 25 ns duration in the repetition rate operation. However, because of the severe impedance mismatch, the power conversion efficiency is only about 4% in the repetition rate operation. In order to eliminate the impedance mismatch and obtain repetitive long-pulse high-power microwave (HPM), a series of experiments are carried out and the recent progress is presented in this paper. In the single-pulse operation, when the diode voltage is 466 kV and current is 41.6 kA, the radiated microwave power is above 2.2 GW, the pulse duration is above 102 ns, the microwave frequency is about 1.74 GHz, and the power conversion efficiency is about 11.5%. In the repetition rate operation, under the condition of the diode voltage about 400 kV, beam current about 38 kA, the radiated microwave power is about 1.0 GW, the pulse duration is about 85 ns. Moreover, the radiated microwave power and the pulse duration decline little by little when the shot numbers increase gradually. The experimental results show that the impedance matching is a vital factor for HPM systems and one of the major technical challenges is to improve the cathode for the repetition rate operation MILO.

  3. Kansas Electric Transmission Lines

    Data.gov (United States)

    Kansas Data Access and Support Center — This data set is a digital representation of the EletcircTransmission lines for the State of Kansas as maintained by the Kansas Corporation Commission. Data is...

  4. Electric Power Transmission Lines

    Data.gov (United States)

    Department of Homeland Security — Transmission Lines are the system of structures, wires, insulators and associated hardware that carry electric energy from one point to another in an electric power...

  5. ''SMILE'': A Self Magnetically Insulated Transmission LinE adder for the 8-stage RADLAC II accelerator

    International Nuclear Information System (INIS)

    Mazarakis, M.G.; Poukey, J.W.; Shope, S.L.; Frost, C.A.; Turman, B.N.; Ramirez, J.J.; Prestwich, K.R.; Pankuch, P.J.

    1991-01-01

    The RADLAC II Self Magnetically Insulated Transmission LinE ''SMILE'' is a coaxial wave guide structure that is composed of two regions: (a) a 9.5-m voltage adder and (b) a 3-m long extension section. The adder section provides for the addition of the input voltages from the individual water-dielectric pulse forming line feeds. The extension section isolates the adder from the magnetically immersed foilless diode electron source load and efficiently transports the pulsed power out from the deionized water tank of the device. The SMILE modification of the RADLAC II accelerator enabled us to produce high quality beams of up to 14 MV, 100 kA. The design and the experimental evaluation of SMILE will be presented and compared with numerical simulation predictions. 12 refs., 9 figs., 1 tab

  6. SMILE'': A Self Magnetically Insulated Transmission LinE adder for the 8-stage RADLAC II accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Mazarakis, M.G.; Poukey, J.W.; Shope, S.L.; Frost, C.A.; Turman, B.N.; Ramirez, J.J.; Prestwich, K.R. (Sandia National Labs., Albuquerque, NM (USA)); Pankuch, P.J. (EG and G Energy Measurements Group, Inc., Albuquerque, NM (USA). Special Projects)

    1991-01-01

    The RADLAC II Self Magnetically Insulated Transmission LinE SMILE'' is a coaxial wave guide structure that is composed of two regions: (a) a 9.5-m voltage adder and (b) a 3-m long extension section. The adder section provides for the addition of the input voltages from the individual water-dielectric pulse forming line feeds. The extension section isolates the adder from the magnetically immersed foilless diode electron source load and efficiently transports the pulsed power out from the deionized water tank of the device. The SMILE modification of the RADLAC II accelerator enabled us to produce high quality beams of up to 14 MV, 100 kA. The design and the experimental evaluation of SMILE will be presented and compared with numerical simulation predictions. 12 refs., 9 figs., 1 tab.

  7. Survey of Magnetic Fields Near BPA 230-kV and 500-kV Transmission Lines.

    Energy Technology Data Exchange (ETDEWEB)

    Perrin, Nancy; Aggarwal, Rajinder Pal; Bracken, T. Daniel

    1991-05-20

    The purpose of this study was to characterize typical levels and variability of 60Hz magnetic fields at the centerline and edge of right-of-way of Bonneville Power Administration (BPA) 230-kV and 500-kV transmission lines. This was accomplished by taking magnetic field measurements at over 800 spans in Oregon and Washington. The spans were sampled using a stratified random sampling procedure with region (East vs. West), voltage (230-kV vs 500-kV), and circuit configuration as strata. There were five different circuit configuration groups for each region/voltage category requiring a total of 200 strata. Magnetic field measurements were taken at 13 locations under each span using an EMDEX-C as a survey meter. Additional information recorded for each span included conductor height (at 10 locations), right-of-way width, longitudinal and lateral slope, time of day, vegetation, terrain, weather conditions, temperature, wind speed, span length and presence of other lines in the corridor. 9 refs., 17 figs., 26 tabs.

  8. Coaxial transmission line - Equalization

    International Nuclear Information System (INIS)

    Bonnerue, J.L.; Fremont, Jacques; Haubtmann, Jack; Pillon, Gerard.

    1981-09-01

    The transmission of electrical signal through a coaxial line is not perfect and signal distortions are increased as much as the frequency spectrum is extended. We have designed and achieved passive filters (named equalizers) with transfer functions which are inverse of coaxial transfer functions. Doing so our attempt is to avoid definitive loss of information in the recorded data. The main feature of our equalization method lies in the fact it could be either an electrical or a numerical correction or both of them. Some examples in the use of this technique are also proposed [fr

  9. High-power electromagnetic wave in a magnetically insulated transmission line of the ANGARA-5-1 facility

    International Nuclear Information System (INIS)

    Samokhin, A. A.

    2010-01-01

    Studies of physical phenomena in magnetically insulated transmission lines (MITLs) of high-power pulsed current generators, analysis of operation of existing megavolt generators, and designing of new high-current generators with a power of up to ∼10 TW require creating an efficient numerical code for modeling the propagation of a high-power electromagnetic pulse in an MITL. This paper presents basic theoretical concepts of MITL operation in the framework of telegraph equations with allowance for electron leakage and variations in the electrode emissivity and analyzes propagation of an electromagnetic wave in the MITLs of the ANGARA-5-1 eight-module facility toward a dynamic load installed in the central unit with a matrix inductance.

  10. Fiber Optic Cryogenic Sensors for Superconducting Magnets and Superconducting Power Transmission lines at CERN

    CERN Document Server

    Chiuchiolo, A; Cusano, A; Bajko, M; Perez, J C; Bajas, H; Giordano, M; Breglio, G; Palmieri, L

    2014-01-01

    The design, fabrication and tests of a new generation of superconducting magnets for the upgrade of the LHC require the support of an adequate, robust and reliable sensing technology. The use of Fiber Optic Sensors is becoming particularly challenging for applications in extreme harsh environments such as ultra-low temperatures, high electromagnetic fields and strong mechanical stresses offering perspectives for the development of technological innovations in several applied disciplines.

  11. Fiber optic cryogenic sensors for superconducting magnets and superconducting power transmission lines at CERN

    Science.gov (United States)

    Chiuchiolo, A.; Bajko, M.; Perez, J. C.; Bajas, H.; Consales, M.; Giordano, M.; Breglio, G.; Palmieri, L.; Cusano, A.

    2014-08-01

    The design, fabrication and tests of a new generation of superconducting magnets for the upgrade of the LHC require the support of an adequate, robust and reliable sensing technology. The use of Fiber Optic Sensors is becoming particularly challenging for applications in extreme harsh environments such as ultra-low temperatures, high electromagnetic fields and strong mechanical stresses offering perspectives for the development of technological innovations in several applied disciplines.

  12. VT Electric Transmission Line Corridors - corridor lines

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The ELTRN layer depicts electric transmission line corridors in Vermont. Various methods have been used to digitize features. The data layer...

  13. Ion diode performance on a positive polarity inductive voltage adder with layered magnetically insulated transmission line flow

    International Nuclear Information System (INIS)

    Hinshelwood, D. D.; Schumer, J. W.; Allen, R. J.; Commisso, R. J.; Jackson, S. L.; Murphy, D. P.; Phipps, D.; Swanekamp, S. B.; Weber, B. V.; Ottinger, P. F.; Apruzese, J. P.; Cooperstein, G.; Young, F. C.

    2011-01-01

    A pinch-reflex ion diode is fielded on the pulsed-power machine Mercury (R. J. Allen, et al., 15th IEEE Intl. Pulsed Power Conf., Monterey, CA, 2005, p. 339), which has an inductive voltage adder (IVA) architecture and a magnetically insulated transmission line (MITL). Mercury is operated in positive polarity resulting in layered MITL flow as emitted electrons are born at a different potential in each of the adder cavities. The usual method for estimating the voltage by measuring the bound current in the cathode and anode of the MITL is not accurate with layered flow, and the interaction of the MITL flow with a pinched-beam ion diode load has not been studied previously. Other methods for determining the diode voltage are applied, ion diode performance is experimentally characterized and evaluated, and circuit and particle-in-cell (PIC) simulations are performed. Results indicate that the ion diode couples efficiently to the machine operating at a diode voltage of about 3.5 MV and a total current of about 325 kA, with an ion current of about 70 kA of which about 60 kA is proton current. It is also found that the layered flow impedance of the MITL is about half the vacuum impedance.

  14. Experimental study on magnetically insulated transmission line electrode surface evolution process under MA/cm current density

    International Nuclear Information System (INIS)

    Zhang, PengFei; Qiu, Aici; Hu, Yang; Yang, HaiLiang; Sun, Jiang; Wang, Liangping; Cong, Peitian

    2016-01-01

    The design of high-current density magnetically insulated transmission line (MITL) is a difficult problem of current large-scale Z-pinch device. In particular, a thorough understanding of the MITL electrode surface evolution process under high current density is lacking. On the “QiangGuang-I” accelerator, the load area possesses a low inductance short-circuit structure with a diameter of 2.85 mm at the cathode, and three reflux columns with a diameter of 3 mm and uniformly distributed circumference at the anode. The length of the high density MITL area is 20 mm. A laser interferometer is used to assess and analyze the state of the MITL cathode and anode gap, and their evolution process under high current density. Experimental results indicate that evident current loss is not observed in the current density area at pulse leading edge, and peak when the surface current density reaches MA/cm. Analysis on electrode surface working conditions indicates that when the current leading edge is at 71.5% of the peak, the total evaporation of MITL cathode structure can be realized by energy deposition caused by ohmic heating. The electrode state changes, and diffusion conditions are reflected in the laser interferometer image. The MITL cathode area mainly exists in metal vapor form. The metal vapor density in the cathode central region is higher than the upper limit of laser penetration density (∼4 × 10 21 /cm 3 ), with an expansion velocity of ∼0.96 km/s. The metal vapor density in the electrode outer area may lead to evident distortion of fringes, and its expansion velocity is faster than that in the center area (1.53 km/s).

  15. Radio and line transmission 2

    CERN Document Server

    Roddy, Dermot

    2013-01-01

    Radio and Line Transmission, Volume 2 gives a detailed treatment of the subject as well as an introduction to additional advanced subject matter. Organized into 14 chapters, this book begins by explaining the radio wave propagation, signal frequencies, and bandwidth. Subsequent chapters describe the transmission lines and cables; the aerials; tuned and coupled circuits; bipolar transistor amplifiers; field-effect transistors and circuits; thermionic valve amplifiers; LC oscillators; the diode detectors and modulators; and the superheterodyne receiver. Other chapters explore noise and interfere

  16. Transmission line fields

    International Nuclear Information System (INIS)

    Jeffers, D.E.

    1991-01-01

    There were reports from Russia in the late 1960's and early 1970's that staff in new 500-kV and 750-kV substations were suffering from headaches and other symptoms broadly associated with fatigue. Whilst the Russian results were not confirmed by independent studies, they did serve to stimulate public concern. In 1979 published results of a study of childhood cancer in Denver, Colorado concentrated attention onto the magnetic rather than the electric field. Research programmes in the United Kingdom and elsewhere are briefly described. Although some studies suggest an association between exposure to 50/60 Hz fields and cancer, other studies do not. Having reviewed the evidence, the International Radiation Protection Association, the World Health Organisation, the U.S. Congress Office of Technology Assessment and the U.K. National Radiological Protection Board all consider that the relation is not established. (author)

  17. Use of a Parallel Plate Transmission Line to Calibrate a Fiber-Optic Coupled Magnetic Field Sensor.

    Science.gov (United States)

    1980-01-01

    field of the transmission line was IN*eu APACHE RPG4?MP9n s H&&..5 AM .&& D of TMa monitored with an EG&G D-dot sensor (HSD-2A) Pdawm&PmI...m/mV) = H = field in which sensor/ trasmitter is immesed. 1.37 A/m, which is 11 percent greater than calculated. Since the transfer impedance of the

  18. Self-Magnetically Insulated Transmission Line ( SMILE'') a new version for the RADLAC II linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Mazarakis, M.G.; Poukey, J.W.; Shope, S.L.; Frost, C.A.; Pankuch, P.J.; Turman, B.N.; Ramirez, J.J.; Prestwich, K.R.

    1990-01-01

    We present here the SMILE modification of the RADLAC II accelerator which enabled us to produce high quality 12--14 MV, 100 kA beams. It consists of replacing the 40-kA 4-MV beam injector, magnetic vacuum transport and accelerating gaps by a long cathode shank which adds up the voltages of the 8 pulse forming lines. The beam now is produced at the end of the accelerator and is free of all the possible instabilities associated with accelerating gaps and magnetic vacuum transport. Annular beams with {beta}{perpendicular} {le} 0.1 and radius r{sub b} {le} 2 cm are routinely obtained and extracted from a small magnetically immersed foilless electron diode. Results of the experimental evaluation are presented and compared with design parameters and numerical simulation predictions. 6 refs., 7 figs., 1 tab.

  19. Coiled transmission line pulse generators

    Science.gov (United States)

    McDonald, Kenneth Fox

    2010-11-09

    Methods and apparatus are provided for fabricating and constructing solid dielectric "Coiled Transmission Line" pulse generators in radial or axial coiled geometries. The pour and cure fabrication process enables a wide variety of geometries and form factors. The volume between the conductors is filled with liquid blends of monomers, polymers, oligomers, and/or cross-linkers and dielectric powders; and then cured to form high field strength and high dielectric constant solid dielectric transmission lines that intrinsically produce ideal rectangular high voltage pulses when charged and switched into matched impedance loads. Voltage levels may be increased by Marx and/or Blumlein principles incorporating spark gap or, preferentially, solid state switches (such as optically triggered thyristors) which produce reliable, high repetition rate operation. Moreover, these Marxed pulse generators can be DC charged and do not require additional pulse forming circuitry, pulse forming lines, transformers, or an a high voltage spark gap output switch. The apparatus accommodates a wide range of voltages, impedances, pulse durations, pulse repetition rates, and duty cycles. The resulting mobile or flight platform friendly cylindrical geometric configuration is much more compact, light-weight, and robust than conventional linear geometries, or pulse generators constructed from conventional components. Installing additional circuitry may accommodate optional pulse shape improvements. The Coiled Transmission Lines can also be connected in parallel to decrease the impedance, or in series to increase the pulse length.

  20. SMILE transmission line adder for RADLAC II

    Energy Technology Data Exchange (ETDEWEB)

    Mazarakis, M.G.; Poukey, J.W.; Shope, S.L.; Frost, C.A.; Turman, B.N.; Ramirez, J.J.; Prestwich, K.R. (Sandia National Labs., Albuquerque, NM (United States)); Pankuch, P.J. (EG and G Energy Measurements Group, Inc., Albuquerque, NM (United States). Special Projects)

    1991-01-01

    SMILE is a coaxial Self Magnetically Insulated Transmission Line voltage adder. It replaces the original beam line of the RADLAC II accelerator by a 12.5 m long cathode electrode. The anode electrode remains practically the same, consisting of the original eight insulating stacks or feeds which are connected with equal diameter stainless steel cylinders. The beam is produced at the end of the accelerator and is free of all the possible instabilities associated with accelerating gaps and magnetic vacuum transport. Annular beams with {beta}{perpendicular} {le} 0.1 and radius r{sub b} {le} 1 cm were routinely obtained and extracted from a small magnetically-immersed foilless electron diode. Results of the experimental evaluation are presented and compared with design parameters and numerical simulation predictions. 4 refs.

  1. SMILE transmission line adder for RADLAC II

    Energy Technology Data Exchange (ETDEWEB)

    Mazarakis, M.G.; Poukey, J.W.; Shope, S.L.; Frost, C.A.; Turman, B.N.; Ramirez, J.J.; Prestwich, K.R. [Sandia National Labs., Albuquerque, NM (United States); Pankuch, P.J. [EG and G Energy Measurements Group, Inc., Albuquerque, NM (United States). Special Projects

    1991-12-31

    SMILE is a coaxial Self Magnetically Insulated Transmission Line voltage adder. It replaces the original beam line of the RADLAC II accelerator by a 12.5 m long cathode electrode. The anode electrode remains practically the same, consisting of the original eight insulating stacks or feeds which are connected with equal diameter stainless steel cylinders. The beam is produced at the end of the accelerator and is free of all the possible instabilities associated with accelerating gaps and magnetic vacuum transport. Annular beams with {beta}{perpendicular} {le} 0.1 and radius r{sub b} {le} 1 cm were routinely obtained and extracted from a small magnetically-immersed foilless electron diode. Results of the experimental evaluation are presented and compared with design parameters and numerical simulation predictions. 4 refs.

  2. Self-Shielding Of Transmission Lines

    Energy Technology Data Exchange (ETDEWEB)

    Christodoulou, Christos [Univ. of New Mexico, Albuquerque, NM (United States)

    2017-03-01

    The use of shielding to contend with noise or harmful EMI/EMR energy is not a new concept. An inevitable trade that must be made for shielding is physical space and weight. Space was often not as much of a painful design trade in older larger systems as they are in today’s smaller systems. Today we are packing in an exponentially growing number of functionality within the same or smaller volumes. As systems become smaller and space within systems become more restricted, the implementation of shielding becomes more problematic. Often, space that was used to design a more mechanically robust component must be used for shielding. As the system gets smaller and space is at more of a premium, the trades starts to result in defects, designs with inadequate margin in other performance areas, and designs that are sensitive to manufacturing variability. With these challenges in mind, it would be ideal to maximize attenuation of harmful fields as they inevitably couple onto transmission lines without the use of traditional shielding. Dr. Tom Van Doren proposed a design concept for transmission lines to a class of engineers while visiting New Mexico. This design concept works by maximizing Electric field (E) and Magnetic Field (H) field containment between operating transmission lines to achieve what he called “Self-Shielding”. By making the geometric centroid of the outgoing current coincident with the return current, maximum field containment is achieved. The reciprocal should be true as well, resulting in greater attenuation of incident fields. Figure’s 1(a)-1(b) are examples of designs where the current centroids are coincident. Coax cables are good examples of transmission lines with co-located centroids but they demonstrate excellent field attenuation for other reasons and can’t be used to test this design concept. Figure 1(b) is a flex circuit design that demonstrate the implementation of self-shielding vs a standard conductor layout.

  3. Sevick's transmission line transformers theory and practice

    CERN Document Server

    Mack, Raymond

    2014-01-01

    An updated and reorganized revision of the classic book Transmission Line Transformers (2001) by Jerry Sevick, this book provides communication engineers with a clear technical presentation of both the theory and practical applications of the transmission of radio communication.

  4. Transmission Line Security Monitor: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    John Svoboda

    2011-04-01

    The Electric Power Transmission Line Security Monitor System Operational Test is a project funded by the Technical Support Working Group (TSWG). TSWG operates under the Combating Terrorism Technical Support Office that functions under the Department of Defense. The Transmission Line Security Monitor System is based on technology developed by Idaho National Laboratory. The technology provides a means for real-time monitoring of physical threats and/or damage to electrical transmission line towers and conductors as well as providing operational parameters to transmission line operators to optimize transmission line operation. The end use is for monitoring long stretches of transmission lines that deliver electrical power from remote generating stations to cities and industry. These transmission lines are generally located in remote transmission line corridors where security infrastructure may not exist. Security and operational sensors in the sensor platform on the conductors take power from the transmission line and relay security and operational information to operations personnel hundreds of miles away without relying on existing infrastructure. Initiated on May 25, 2007, this project resulted in pre-production units tested in realistic operational environments during 2010. A technology licensee, Lindsey Manufacturing of Azusa California, is assisting in design, testing, and ultimately production. The platform was originally designed for a security monitoring mission, but it has been enhanced to include important operational features desired by electrical utilities.

  5. Electrical and Biological Effects of Transmission Lines: A Review.

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jack M.

    1989-06-01

    This review describes the electrical properties of a-c and d-c transmission lines and the resulting effects on plants, animals, and people. Methods used by BPA to mitigate undesirable effects are also discussed. Although much of the information in this review pertains to high-voltage transmission lines, information on distribution lines and electrical appliances is included. The electrical properties discussed are electric and magnetic fields and corona: first for alternating-current (a-c) lines, then for direct current (d-c).

  6. Transmission Lines in CMOS: An Explorative Study

    NARCIS (Netherlands)

    Klumperink, Eric A.M.; Kreienkamp, R.; Ellermeyer, T.; Langmann, U.

    On-chip transmission line modelling and design become increasingly important as frequencies are continuously going up. This paper explores possibilities to implement transmission lines on CMOS ICs via coupled coplanar strips. EM-field simulations with SONNET are used to estimate important

  7. Improved Field Homogeneity for Transmission Line MRI Coils Using Series Capacitors

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Dong, Yunfeng

    2015-01-01

    High field magnetic resonance imaging (MRI) systems often use short sections of transmission lines for generating and sensing alternating magnetic fields. Due to distributed nature of transmission lines, the generated field is inhomogeneous. This work investigates the application of series...... capacitors to improve the field homogeneity. The resulting magnetic field distribution is estimated analytically and evaluated numerically. The results are compared to a case of a conventional transmission line coil realization....

  8. Microwave transmission-line impedance data

    CERN Document Server

    Gunston, M A R

    1996-01-01

    A compendium of data for computing the characteristic impedance of transmission lines based on physical dimensions. Covers both conventional structures and unusual geometries, including coaxial, eccentric and elliptic coaxial, twin-wire, wire-above-ground, microstrip and derivatives, stripline, slabline and trough line. Also details numerous configurations of coupled lines.

  9. Calculated Hanle transmission and absorption spectra of the 87Rb D1 line with residual magnetic field for arbitrarily polarized light

    International Nuclear Information System (INIS)

    Noh, Heung-Ryoul; Moon, Han Seb

    2010-01-01

    This paper reports a theoretical study on the transmission spectra of an arbitrarily polarized laser beam through a rubidium cell with or without a buffer gas in Hanle-type coherent population trapping (CPT). This study examined how laser polarization, transverse magnetic field, and collisions with buffer gas affects the spectrum. The transmission spectrum due to CPT and the absorption spectrum due to the level crossing absorption (LCA) were calculated according to the laser polarization. The results show that the LCA is strongly dependent on the transverse magnetic field and interaction time of the atoms with a laser light via collisions with the buffer gas. In addition, the spectral shape of the calculated Hanle spectrum is closely related to the direction between the (stray) transverse magnetic field and polarization of the laser.

  10. VT Electric Transmission Line Corridors - substation points

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The ELTRN layer depicts electric transmission line corridors in Vermont. Various methods have been used to digitize features. The data layer...

  11. Transmission Line Resonator Segmented with Series Capacitors

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Boer, Vincent; Petersen, Esben Thade

    2016-01-01

    Transmission line resonators are often used as coils in high field MRI. Due to distributed nature of such resonators, coils based on them produce inhomogeneous field. This work investigates application of series capacitors to improve field homogeneity along the resonator. The equations for optimal...... values of evenly distributed capacitors are presented. The performances of the segmented resonator and a regular transmission line resonator are compared....

  12. Signal Transmission on Power Lines

    DEFF Research Database (Denmark)

    Dalby, Arne Brejning

    1997-01-01

    In the analysis of power-line networks over a large frequency span, the time-domain method used in programs like EMTP (Electromagnetic Time domain Program) can not be used. A more rigorous analysis method must be employed. The correct analysis method (assuming TEM-mode propagation) for multiple...

  13. Transmission Line Series Compensation for Wind Energy Transmission

    International Nuclear Information System (INIS)

    Palanichamy, C; Wong, Y C

    2015-01-01

    Wind energy has demonstrated to be a clean, copious and absolutely renewable source of energy, and the large penetration of it into the power grid indicates that wind energy is considered an effective means of power generation, Transmission of wind energy from remote locations to load centers necessitates long transmission lines. Series compensation is a proven and economical transmission solution to address system power transfer strength, grid stability, and voltage profile issues of long transmission lines. In this paper, a programmable approach to determine the capacitive reactance of series capacitor and optimum location for its placement to achieve maximum power transfer gas been presented. The respective program with sample solutions has been provided for real-time applications. (paper)

  14. Optimal Value of Series Capacitors for Uniform Field Distribution in Transmission Line MRI Coils

    OpenAIRE

    Vitaliy Zhurbenko

    2016-01-01

    Transmission lines are often used as coils in high field magnetic resonance imaging (MRI). Due to the distributed nature of transmission lines, coils based on them produce inhomogeneous field. This work investigates application of series capacitors to improve field homogeneity along the coil. The equations for optimal values of evenly distributed capacitors are derived and expressed in terms of the implemented transmission line parameters. The achieved magnetic field homogeneity is estimated ...

  15. Conceptual design for transmission line inspection robot

    International Nuclear Information System (INIS)

    Jalal, M F Abdul; Sahari, K S Mohamed; Anuar, A; Arshad, A D Mohd; Idris, M S

    2013-01-01

    Power transmission line is used for power distribution purposes due to their cost effective measure compared to underlying cable. However, prolonged exposure to natural weather may cause fatigue stress to the lines as well as induce material failure. Therefore, periodical line inspection is considered uttermost important as a preventive measure to avoid power outage. However, transmission line inspection has always been a high risk and expensive work. Hazardous works that may harm operator as well as routine that requires precise handling can be performed by robots. Various types of robots have been designed and developed for line inspection but only perform well on a straight and continuous line. As these robots encounter an obstacle during the inspection, then the real problem in terms of robot stability and smooth operation arises. In this paper, conceptual design and evaluation for transmission line inspection robot is presented. The inspection robot mobile robot must be able to bypass or avoid obstacles as it travels along the power transmission line.

  16. Explanation of the Inverse Doppler Effect Observed in Nonlinear Transmission Lines

    International Nuclear Information System (INIS)

    Kozyrev, Alexander B.; Weide, Daniel W. van der

    2005-01-01

    The theory of the inverse Doppler effect recently observed in magnetic nonlinear transmission lines is developed. We explain the crucial role of the backward spatial harmonic in the occurrence of an inverse Doppler effect and draw analogies of the magnetic nonlinear transmission line to the backward wave oscillator

  17. Transmission of Electric Energy Along Long Lines

    Directory of Open Access Journals (Sweden)

    Berzan V.P.

    2009-08-01

    Full Text Available Transmission of electric energy along long lines is examined and characteristics of the change of capacities at the beginning and at the end of a line are submitted: factor of capacity, efficiency of a transmission line, currents depending on length, parameters of a line and parameters of loading. Influence of losses upon the dynamics of instant values of voltages and currents in the opened and short-circuited long lines is investigated and effects of nonlinearity in such chains are revealed at a power supply from a sinusoidal source of voltage. It is shown, that the method of complex amplitudes is not always applicable for the calculation of modes in long lines.

  18. Optimal Value of Series Capacitors for Uniform Field Distribution in Transmission Line MRI Coils

    Directory of Open Access Journals (Sweden)

    Vitaliy Zhurbenko

    2016-01-01

    Full Text Available Transmission lines are often used as coils in high field magnetic resonance imaging (MRI. Due to the distributed nature of transmission lines, coils based on them produce inhomogeneous field. This work investigates application of series capacitors to improve field homogeneity along the coil. The equations for optimal values of evenly distributed capacitors are derived and expressed in terms of the implemented transmission line parameters. The achieved magnetic field homogeneity is estimated under quasistatic approximation and compared to the regular transmission line resonator. Finally, a more practical case of a microstrip line coil with two series capacitors is considered.

  19. Transmission Line Adapted Analytical Power Charts Solution

    Science.gov (United States)

    Sakala, Japhet D.; Daka, James S. J.; Setlhaolo, Ditiro; Malichi, Alec Pulu

    2017-08-01

    The performance of a transmission line has been assessed over the years using power charts. These are graphical representations, drawn to scale, of the equations that describe the performance of transmission lines. Various quantities that describe the performance, such as sending end voltage, sending end power and compensation to give zero voltage regulation, may be deduced from the power charts. Usually required values are read off and then converted using the appropriate scales and known relationships. In this paper, the authors revisit this area of circle diagrams for transmission line performance. The work presented here formulates the mathematical model that analyses the transmission line performance from the power charts relationships and then uses them to calculate the transmission line performance. In this proposed approach, it is not necessary to draw the power charts for the solution. However the power charts may be drawn for the visual presentation. The method is based on applying derived equations and is simple to use since it does not require rigorous derivations.

  20. Flux Cloning in Josephson Transmission Lines

    International Nuclear Information System (INIS)

    Gulevich, D.R.; Kusmartsev, F.V.

    2006-01-01

    We describe a novel effect related to the controlled birth of a single Josephson vortex. In this phenomenon, the vortex is created in a Josephson transmission line at a T-shaped junction. The 'baby' vortex arises at the moment when a 'mother' vortex propagating in the adjacent transmission line passes the T-shaped junction. In order to give birth to a new vortex, the mother vortex must have enough kinetic energy. Its motion can also be supported by an externally applied driving current. We determine the critical velocity and the critical driving current for the creation of the baby vortices and briefly discuss the potential applications of the found effect

  1. Composite Based EHV AC Overhead Transmission Lines

    DEFF Research Database (Denmark)

    Sørensen, Thomas Kjærsgaard

    ) levels are still not seen as possibility, the future expansion of transmission grids are dependent on new solutions with lessened environment impact, especially with regard to the visual impact. In the present Thesis, composite materials and composite based overhead line components are presented...... and analysed with regard to the possibilities, limitations and risks widespread application of composite materials on EHV AC overhead transmission lines may present. To form the basis for evaluation of the useability of composite materials, dierent overhead line projects aimed at reducing the environmental...... impact are analysed with regard to their visual impact reducing design steps. These are used to form the basis for overhead line system design ideas, which are analysed with regard to application of composite materials and components. Composite materials and components, when applied in EHV systems...

  2. Tornado risk model for transmission line design

    CSIR Research Space (South Africa)

    Milford, RV

    1997-11-01

    Full Text Available is in combination with ice loading. The wind load used in most codes of practice and design recommendations for transmission line design have until recently been based almost exclusively on large-scale wind storms, which may include severe storms such as hurricanes...

  3. Stabilizing Fiber-Optic Transmission Lines

    Science.gov (United States)

    Lutes, G. F.; Lau, K. Y.

    1984-01-01

    Voltage-controlled optical phase shifter is key. Optical phase shifter stabilizes propagation delay of fiber-optic transmission line by compensating for temperature and pressure effects. Applicable to phased array antenna systems and very-long-baseline interferometer distribution systems.

  4. Modeling of Electromagnetic Wave Propagation with Tapered Transmission Line

    Science.gov (United States)

    Lee, Kun-A.; Ko, Kwang-Cheol

    2012-09-01

    Tapered transmission line was used for impedance matching, for high voltage pulse, and atmospheric medium is applied to characteristic equation of tapered transmission line and reflection coefficient so that nonlinear load and circuit modeling of atmospheric medium was simulated by electromagnetic transient program (EMTP). A characteristic of atmospheric medium and Time delay are decided by inductance and capacitance of tapered transmission line. For electromagnetic wave propagation modeling, in this paper, tapered transmission line is implemented. It is difficult to model tapered transmission line directly. Other transmission line that can be expressed by the circuit is used. So object of this paper is efficient modeling of tapered transmission line.

  5. An analytical theory of transmission line shielding

    International Nuclear Information System (INIS)

    Pettersson, Per

    1993-01-01

    The classical electrogeometric model of shielding failure flashovers on transmission lines is investigated by analytical methods. Most of the basic elements that has appeared in the literature on the subject have been incorporated and put into a comprehensive model. These elements are: tower top geometry, structure height above ground, line insulation, lateral slope of ground, probability distribution of lightning currents, ratio of striking distances to ground wire and earth relative to conductor, and probability distribution of lightning leader approach angle to ground. Departing from a basic idealistic case, the sensitivity of the model to variations in these parameters is studied. Numerical examples are given. 8 refs, 8 figs, 1 tab

  6. Flux qubit to a transmission line

    Energy Technology Data Exchange (ETDEWEB)

    Haeberlein, Max; Baust, Alexander; Zhong, Ling; Gross, Rudolf [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Physik-Department, TU Muenchen, Garching (Germany); Nanosystems Initiative Munich (NIM), Muenchen (Germany); Anderson, Gustav; Wang, Lujun; Eder, Peter; Fischer, Michael; Goetz, Jan; Xie, Edwar; Schwarz, Manuel; Wulschner, Karl Friedrich; Deppe, Frank; Fedorov, Kirill; Huebl, Hans; Menzel, Edwin [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Physik-Department, TU Muenchen, Garching (Germany); Marx, Achim [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany)

    2015-07-01

    Within the last decade, superconducting qubits coupled to microwave resonators have been extensively studied within the framework of quantum electrodynamics. Ultimately, quantum computing seems within reach in such architectures. However, error correction schemes are necessary to achieve the required fidelity in multi-qubit operations, drastically increasing the number of qubits involved. In this work, we couple a flux qubit to a transmission line where it interacts with itinerant microwave photons granting access to all-optical quantum computing. In this approach, travelling photons generate entanglement between two waveguides, containing the qubit information. In this presentation, we show experimental data on flux qubits coupled to transmission lines. Furthermore, we will discuss entanglement generation between two separate paths.

  7. Optimal Value of Series Capacitors for Uniform Field Distribution in Transmission Line MRI Coils

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy

    2016-01-01

    Transmission lines are often used as coils in high field magnetic resonance imaging (MRI). Due to the distributed nature of transmission lines, coils based on them produce inhomogeneous field. This work investigates application of series capacitors to improve field homogeneity along the coil...

  8. Geotechnical assessments of upgrading power transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Andrew [Coffey Geotechnics Ltd., Harrogate (United Kingdom)

    2012-11-01

    One of the consequences of increasing demand for energy is a corresponding requirement for increased energy distribution. This trend is likely to be magnified by the current tendency to generate power in locations remote from centres of population. New power transmission routes are expensive and awkward to develop, and there are therefore benefits to be gained by upgrading existing routes. However, this in turn raises problems of a different nature. The re-use of any structure must necessarily imply the acceptance of unknowns. The upgrading of transmission lines is no exception to this, particularly when assessing foundations, which in their nature are not visible. A risk-based approach is therefore used. This paper describes some of the geotechnical aspects of the assessment of electric power transmission lines for upgrading. It briefly describes the background, then discusses some of the problems encountered and the methods used to address them. These methods are based mainly on information obtained from desk studies and walkover surveys, with a limited amount of intrusive investigation. (orig.)

  9. Optoelectronic line transmission an introduction to fibre optics

    CERN Document Server

    Tricker, Raymond L

    2013-01-01

    Optoelectronic Line Transmission: An Introduction to Fibre Optics presents a basic introduction as well as a background reference manual on fiber optic transmission. The book discusses the basic principles of optical line transmission; the advantages and disadvantages of optical fibers and optoelectronic signalling; the practical applications of optoelectronics; and the future of optoelectronics. The text also describes the theories of optical line transmission; fibers and cables for optical transmission; transmitters including light-emitting diodes and lasers; and receivers including photodi

  10. MEMS-based transmission lines for microwave applications

    Science.gov (United States)

    Wu, Qun; Fu, Jiahui; Gu, Xuemai; Shi, Huajuan; Lee, Jongchul

    2003-04-01

    This paper mainly presents a briefly review for recent progress in MEMS-based transmission lines for use in microwave and millimeterwave range. MEMS-based transmission lines including different transmission line structure such as membrane-supported microstrip line microstrip line, coplanar microshield transmission line, LIGA micromachined planar transmission line, micromachined waveguides and coplanar waveguide are discussed. MEMS-based transmission lines are characterized by low propagation loss, wide operation frequency band, low dispersion and high quality factor, in addition, the fabrication is compatible with traditional processing of integrated circuits (IC"s). The emergence of MEMS-based transmission lines provided a solution for miniaturizing microwave system and monolithic microwave integrated circuits.

  11. Dispersion-managed electrical transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Koon, K. Tse Ve [Institut Carnot de Bourgogne, UMR 5209 CNRS, Universite de Bourgogne, 9 Av. A. Savary, B.P. 47870, 21078 Dijon Cedex (France)], E-mail: kevin@u-bourgogne.fr; Dinda, P. Tchofo [Institut Carnot de Bourgogne, UMR 5209 CNRS, Universite de Bourgogne, 9 Av. A. Savary, B.P. 47870, 21078 Dijon Cedex (France)], E-mail: tchofo@u-bourgogne.fr; Marquie, P. [Laboratoire LEII, UMR CNRS No. 5158, Universite de Bourgogne, Aile de l' Ingenieur, B.P. 47870, 21078 Dijon Cedex (France)], E-mail: patrick.marquie@u-bourgogne.fr

    2009-05-30

    We examine the ability of electrical pulses to execute a highly stable propagation in a special electrical network made of concatenated pieces of discrete electrical lines with alternately positive and negative signs of the second-order dispersion. We show that such networks, called dispersion-managed electrical lines, induce a pulse breathing phenomenon, that is a dynamical behaviour with alternate regimes of pulse broadening and compression. This breathing phenomenon, which prevents the pulse from broadening without bounds during propagation in the network is the most appealing feature of the technique of dispersion management developed in the last decade in the area of optical communications. Meanwhile, we show that the benefit of using dispersion management in ETLs is strongly mitigated by the third-order dispersion and the losses at the junction points between adjacent pieces of line. These come into play as major factors of impairment for the pulse robustness with a much stronger impact than in dispersion-managed optical transmission lines.

  12. Rotating superconductor magnet for producing rotating lobed magnetic field lines

    Science.gov (United States)

    Hilal, Sadek K.; Sampson, William B.; Leonard, Edward F.

    1978-01-01

    This invention provides a rotating superconductor magnet for producing a rotating lobed magnetic field, comprising a cryostat; a superconducting magnet in the cryostat having a collar for producing a lobed magnetic field having oppositely directed adjacent field lines; rotatable support means for selectively rotating the superconductor magnet; and means for energizing the superconductor magnet.

  13. Multistage linear electron acceleration using pulsed transmission lines

    International Nuclear Information System (INIS)

    Miller, R.B.; Prestwich, K.R.; Poukey, J.W.; Epstein, B.G.; Freeman, J.R.; Sharpe, A.W.; Tucker, W.K.; Shope, S.L.

    1981-01-01

    A four-stage linear electron accelerator is described which uses pulsed radial transmission lines as the basic accelerating units. An annular electron beam produced by a foilless diode is guided through the accelerator by a strong axial magnetic field. Synchronous firing of the injector and the acccelerating modules is accomplished with self-breaking oil switches. The device has accelerated beam currents of 25 kA to kinetic energies of 9 MV, with 90% current transport efficiency. The average accelerating gradient is 3 MV/m

  14. Induced voltages in metallic pipelines near power transmission lines

    International Nuclear Information System (INIS)

    Grcev, Leonid; Jankov, Voislav; Filiposki, Velimir

    2002-01-01

    With the continuous development of the electric power system and the pipeline networks used to convey oil or natural gas, cases of close proximity of high voltage structures and metallic pipelines become more and more frequent. Accordingly there is a growing concern about possible hazards resulting from voltages induced in the metallic pipelines by magnetic coupling with nearby power transmission lines. This paper presents a methodology for computation of the induced voltages in buried isolated metallic pipelines. A practical example of computation is also presented. (Author)

  15. Survey of transmission line corridors. [Data on delays in transmission line construction

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-05

    The intent of this study is to determine the extent of delays experienced in planning and constructing transmission lines in the continental United States. The reasons for the delays are identified for each line studied and their effect on the total electrical system is sought. Data was collected for 136 different lines either recently built or currently under study. Statistics were developed for each line in several categories and comparisons of lines delayed were made by company, area served and generation capacity. From the study presented here it was found that: right-of-way acquisition procedures including condemnation and easement negotiation practices delay more projects than local, state and federal regulatory requirements combined; load growth reductions particularly in the east have reduced the impact of regulatory delays; the south, southeast and southwestern areas of the country experience fewer delays in constructing transmission lines than the more populated states, and the cost for corridor delays was responded to for only 17 of the 142 projects surveyed. By far the most costly delay is the expense of condemning land for transmission right-of-way.

  16. On the applicability of conventional transmission line theory within cavities

    Directory of Open Access Journals (Sweden)

    F. Gronwald

    2006-01-01

    Full Text Available We investigate whether or not conventional transmission line theory needs to be modified if transmission lines are considered that are located in a cavity rather than in free space. Our analysis is based on coupled Pocklington's equations that can be reduced to integral equations for the antenna mode and the transmission line mode. Under the usual assumptions of conventional transmission line theory these modes do approximately decouple within a cavity. As a result, cavity properties will primarily influence the antenna mode but not the transmission line mode.

  17. Characterization of superconducting transmission line resonators

    Energy Technology Data Exchange (ETDEWEB)

    Goetz, Jan; Summer, Philipp; Meier, Sebastian; Haeberlein, Max; Wulschner, Karl Friedrich; Eder, Peter; Fischer, Michael; Schwarz, Manuel; Deppe, Frank; Fedorov, Kirill; Huebl, Hans; Menzel, Edwin [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Physik-Department, TU Muenchen, Garching (Germany); Krawczyk, Marta; Marx, Achim [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Baust, Alexander; Xie, Edwar; Zhong, Ling; Gross, Rudolf [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Physik-Department, TU Muenchen, Garching (Germany); Nanosystems Initiative Munich (NIM), Muenchen (Germany)

    2015-07-01

    Superconducting transmission line resonators are widely used in circuit quantum electrodynamics experiments as quantum bus or storage devices. For these applications, long coherence times, which can be linked to the internal quality factor of the resonators, are crucial. Here, we show a systematic study of the internal quality factor of niobium thin film resonators. We analyze different cleaning methods and substrate parameters for coplanar waveguide as well as microstrip geometries. In addition, we investigate the impact of a niobium-aluminum interface which is necessary for galvanically coupled flux qubits made from aluminum. This interface can be avoided by fabricating the complete resonator-qubit structure using Al/AlO{sub x}/Al technology during fabrication.

  18. Symmetry-Related Electromagnetic Properties of Resonator-Loaded Transmission Lines and Applications

    Directory of Open Access Journals (Sweden)

    Jordi Naqui

    2015-05-01

    Full Text Available This paper reviews the recent progress in the analysis and applications of the symmetry-related electromagnetic properties of transmission lines loaded with symmetric configurations of resonant elements. It will be shown that the transmission characteristics of these reactively loaded lines can be controlled by the relative orientation between the line and the resonant elements. Two main types of loaded lines are considered: (i resonance-based structures; and (ii frequency-splitting structures. In resonance-based transmission lines, a line is loaded with a single resonant (and symmetric element. For a perfectly symmetric structure, the line is transparent if the line and resonator exhibit symmetry planes of different electromagnetic nature (electric or magnetic wall, whereas the line exhibits a notch (resonance in the transmission coefficient if the symmetry planes behave as either electric or magnetic walls (symmetric configuration, or if symmetry is broken. In frequency-splitting lines, paired resonators are typically loaded to the transmission line; the structure exhibits a single notch for the symmetric configuration, whereas generally two split notches appear when symmetry is disrupted. Applications of these structures include microwave sensors (e.g., contactless sensors of spatial variables, selective mode suppressors (of application in common-mode suppressed differential lines, for instance and spectral signature barcodes, among others.

  19. 7 CFR 1726.77 - Substation and transmission line construction.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Substation and transmission line construction. 1726... UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Substation and Transmission Facilities § 1726.77 Substation and transmission line construction. (a) Contract...

  20. Power flow studies in HVAC and HVDC transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Oyedokun, D.T.; Folly, K.A. [Cape Town Univ. (South Africa). Dept. of Electrical Engineering

    2008-07-01

    Flexible AC transmission system (FACTS) devices, additional high voltage AC (HVAC) lines, and additional HVDC transmission lines can all be used to increase the capacity of transmission infrastructure. In this paper, 3 case studies were presented to evaluate the different technologies. Power flow analyses were conducted in order to determine the most feasible method of increasing capacity. A 35 per cent increase in load demand was considered in relation to changes in power flow, rotor angle, loading, and reactive power compensation. The study showed that DC limits were reduced at the rectifier substation, and more power was routed via the HVAC line while less power was routed via the HVDC line. A comparison of the case studies showed that using an HVAC transmission line in parallel with an additional HVAC line was the most suitable method of increasing transmission infrastructure. Transmission losses for the double circuit HVAC lines were approximately 60 MW. 13 refs., 6 tabs., 6 figs.

  1. Nonlinear left-handed transmission line metamaterials

    International Nuclear Information System (INIS)

    Kozyrev, A B; Weide, D W van der

    2008-01-01

    Metamaterials, exhibiting simultaneously negative permittivity ε and permeability μ, more commonly referred to as left-handed metamaterials (LHMs) and also known as negative-index materials, have received substantial attention in the scientific and engineering communities [1]. Most studies of LHMs (and electromagnetic metamaterials in general) have been in the linear regime of wave propagation and have already inspired new types of microwave circuits and devices. The results of these studies have already been the subject of numerous reviews and books. This review covers a less explored but rapidly developing area of investigation involving media that combine nonlinearity (dependence of the permittivity and permeability on the magnitude of the propagating field) with the anomalous dispersion exhibited by LHM. The nonlinear phenomena in such media will be considered on the example of a model system: the nonlinear left-handed transmission line. These nonlinear phenomena include parametric generation and amplification, harmonic and subharmonic generation as well as modulational instabilities and envelope solitons. (topical review)

  2. Matching problems in pulse power radial transmission lines

    International Nuclear Information System (INIS)

    Mittag, K.; Brandelik, A.

    1984-12-01

    In this report we study the power transfer from a generator along a coaxial transmission line followed by a radial transmission line into a load, which in our application is a pseudo-spark plasma of about one millimeter diameter and about 15 cm in length. First the theoretical background based on transmission line theory is described. Then numerical results are presented. The main conclusion is that when matching the pulse power generator to the pseudo-spark plasma, the effect of the impedance transformation caused by the radial transmission line has to be taken into account. The conditions to obtain an optimal match are described. (orig.) [de

  3. 77 FR 35366 - Albany-Eugene Transmission Line Rebuild Project

    Science.gov (United States)

    2012-06-13

    ... materials, removing vegetation including danger trees, and revegetating areas disturbed by construction... implement the Proposed Action Alternative, based on the Albany-Eugene Transmission Line Rebuild Project (DOE...

  4. Centralized Coordination of Load Shedding & Protection System of Transmission Lines

    DEFF Research Database (Denmark)

    Hoseinzadeh, Bakhtyar; Bak, Claus Leth

    2018-01-01

    The power system integrity is vulnerable to thermal limit of transmission lines due to overloading and consequently activation of their protection devices following severe contingencies. In this paper, the loading rate of transmission lines is monitored online and is considered in the centralized......, over current protection....

  5. Analysis of some coplanar transmission lines: coplanar coupled lines, coplanar coupled striplines, and coplanar coupled lines with rectangular microshield

    Science.gov (United States)

    Yuan, Naichang; He, Jianguo; Yao, Demiao; Dai, Qin; Lin, Weigan

    1995-06-01

    Two types of coplanar transmission lines, rectangular microshield coplanar coupled lines (RMCCL) and coplanar coupled rectangular microshield lines (CCRML), are proposed for MMIC applications. These are developed from coplanar coupled lines (CCL) and coplanar coupled strip lines (CCS). Analytic formulas are presented for calculating the quasistatic TEM parameters of these coupled lines by means of exact conformal mapping techniques. Numerical results are also presented to illustrate the properties of these coplanar transmission lines.

  6. Line formation in microturbulent magnetic fields

    International Nuclear Information System (INIS)

    Domke, H.; Pavlov, G.G.

    1979-01-01

    The formation of Zeeman lines in Gaussian microturbulent magnetic fields is considered assuming LTE. General formulae are derived for the local mean values of the transfer matrix elements. The cases of one-dimensional (longitudinal), isotropic, and two-dimensional (transversal) magnetic microturbulence are studied in some detail. Asymptotic formulae are given for small mean as well as for small microturbulent magnetic fields. Characteristic effects of magnetic microturbulence on the transfer coefficients are: (i) the broadening of the frequency contours, although only for the case of longitudinal Zeeman effect and longitudinal magnetic microturbulence this effect can be described analogous to Doppler broadening, (ii) the appearance of a pseudo-Zeeman structure for nonlongitudinal magnetic microturbulence, (iii) the reduction of maximal values of circular polarization, and (iv) the appearance of characteristic linear polarization effects due to the anisotropy of the magnetic microturbulence. Line contours and polarization of Zeeman triplets are computed for Milne-Eddington atmospheres. It is shown that magnetic intensification due to microturbulent magnetic fields may be much more efficient than that due to regular fields. The gravity center of a Zeeman line observed in circularly polarized light remains a reasonable measure of the line of sight component of the mean magnetic field for a line strength eta 0 < approx. 2. For saturated lines, the gravity center distance depends significantly on the magnetic microturbulence and its anisotropy. The influence of magnetic microturbulence on the ratio of longitudinal field magnetographic signals shows that unique conclusions about the magnetic microstructure can be drawn from the line ratio measurements only in combination with further spectroscopic data or physical reasoning. (orig.)

  7. Magnetic resonance force microscopy using ferromagnetic resonance of a magnetic tip excited by microwave transmission via a coaxial resonator

    Science.gov (United States)

    Kinoshita, Yukinori; Li, Yan Jun; Yoshimura, Satoru; Saito, Hitoshi; Sugawara, Yasuhiro

    2017-12-01

    The present work proposes magnetic resonance force microscopy (MRFM) based on ferromagnetic resonance (FMR) modulation of a magnetic tip using microwave transmission via a coaxial resonator instead of using conventional microwave irradiation by an external antenna. In this MRFM, the coaxial resonator is electrically connected to the magnetic cantilever tip, which enables simple implementation of FMR excitation of a magnetic tip in conventional magnetic force microscopy. The FMR frequency of the tip can be easily extracted from the reflection spectrum of a transmission line connected to the magnetic tip. The excitation of tip FMR is confirmed from the microwave frequency dependence of the mechanical response of the tip oscillation. This MRFM is effective for extracting the magnetic interaction force near a sample surface without perturbation of its magnetic state. Nanometer-scale imaging of magnetic domain structures on a demagnetized thin-film permanent magnet is successfully demonstrated.

  8. Determination of Transmission Line Impedance Matching Parameters

    African Journals Online (AJOL)

    The analysis of measured and computed matching parameters show that the values obtained are within the acceptable standard threshold values of Voltage Standing Wave Ratio ≤1.50 and Return loss ≥ +14dB used by telecommunication transmission designers worldwide. Keywords: Impedance matching, voltage ...

  9. Propagation behaviour of overhead transmission lines

    African Journals Online (AJOL)

    2004-02-27

    Feb 27, 2004 ... leading to low Signal to Noise Ratios (SNR) and consequent reduced propagation conditions require specific transmission and reception conditions over .... the ambient temperature and wind velocity, intensity of solar radiation, conditions of conductor surface and the conductor resistance. This temperature ...

  10. Coupling and corona effects research plan for transmission lines. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bridges, J E; Formanek, V C

    1976-06-01

    Concern has arisen over the possible effects of electric and magnetic fields produced by EHV-UHV transmission lines. Past and ongoing research concerning the electric and magnetic field effects from EHV-UHV transmission lines was reviewed as it pertains to the following areas: (1) electromagnetic interference, (2) acoustic noise, (3) generation of gaseous effluents, and (4) safety considerations of induced voltages and currents. The intent of this review was to identify the short and long range research projects required to address these areas. The research plan identifies and gives priority to twenty programs in corona and coupling effects. In the case of the corona effects, a number of programs were recommended for acoustic noise and electromagnetic interference to delineate improved power line design criteria in terms of social, meteorological, geographical and cost constraints. Only one project is recommended in the case of ozone generation, because the results of comprehensive analyses, laboratory studies and field measurements have demonstrated that power lines do not contribute significant quantities of ozone. In the case of the coupling effects, a number of programs are recommended for HVAC transmission lines to improve the theoretically developed design guidelines by considering practical constraints. For HVDC transmission lines, programs are suggested to engender a better theoretical understanding and practical measurements capability for the coupling mechanisms of the dc electric and magnetic field with nearby objects. The interrelationship of the programs and their role in a long-term research plan is also discussed.

  11. Bottlenecks reduction using superconductors in high voltage transmission lines

    Directory of Open Access Journals (Sweden)

    Daloub Labib

    2016-01-01

    Full Text Available Energy flow bottlenecks in high voltage transmission lines known as congestions are one of the challenges facing power utilities in fast developing countries. Bottlenecks occur in selected power lines when transmission systems are operated at or beyond their transfer limits. In these cases, congestions result in preventing new power supply contracts, infeasibility in existing contracts, price spike and market power abuse. The “Superconductor Technology” in electric power transmission cables has been used as a solution to solve the problem of bottlenecks in energy transmission at high voltage underground cables and overhead lines. The increase in demand on power generation and transmission happening due to fast development and linked to the intensive usage of transmission network in certain points, which in turn, lead to often frequent congestion in getting the required power across to where it is needed. In this paper, a bottleneck in high voltage double overhead transmission line with Aluminum Conductor Steel Reinforced was modeled using conductor parameters and replaced by Gap-Type Superconductor to assess the benefit of upgrading to higher temperature superconductor and obtain higher current carrying capacity. This proved to reduce the high loading of traditional aluminum conductors and allow more power transfer over the line using superconductor within the same existing right-of-way, steel towers, insulators and fittings, thus reducing the upgrade cost of building new lines.

  12. Magnetic bearing optical delay line

    NARCIS (Netherlands)

    Dool, T.C. van den; Kamphues, F.G.; Fouss, B.; Henrioulle, K.; Hogenhuis, H.

    2004-01-01

    TNO TPD, in close cooperation with Micromega-Dynamics and Dutch Space, has developed an advanced Optical Delay Line (ODL) for use in PRIMA, GENIE and other ground based interferometers. The delay line design is modular and flexible, which makes scaling for other applications a relatively easy task.

  13. Simulation of Series Compensated Transmission Lines Protected with Mov

    OpenAIRE

    Abdolamir Nekoubin

    2011-01-01

    In this paper the behavior of fixed series compensated extra high voltage transmission lines during faults is simulated. Many over-voltage protection schemes for series capacitors are limited in terms of size and performance, and are easily affected by environmental conditions. While the need for more compact and environmentally robust equipment is required. use of series capacitors for compensating part of the inductive reactance of long transmission lines increases the ...

  14. Coupled Transmission Lines as Impedance Transformer

    DEFF Research Database (Denmark)

    Jensen, Thomas; Zhurbenko, Vitaliy; Krozer, Viktor

    2007-01-01

    A theoretical investigation of the use of a coupled line section as an impedance transformer is presented. We show how to properly select the terminations of the coupled line structures for effective matching of real and complex loads in both narrow and wide frequency ranges. The corresponding...... circuit configurations and the design procedures are proposed. Synthesis relations are derived and provided for efficient matching circuit construction. Design examples are given to demonstrate the flexibility and limitations of the design methods and to show their validity for practical applications....... Wideband matching performance with relative bandwidth beyond 100% and return loss > 20 dB is demonstrated both theoretically and experimentally. Good agreement is achieved between the measured and predicted performance of the coupled line transformer section....

  15. Analysis of transmission lines loaded with pairs of coupled resonant elements and application to sensors

    Energy Technology Data Exchange (ETDEWEB)

    Naqui, J.; Su, L., E-mail: lijuan.suri.su@gmail.com; Mata, J.; Martín, F., E-mail: Ferran.Martin@uab.es

    2015-06-01

    This paper is focused on the analysis of transmission lines loaded with pairs of magnetically coupled resonators. We have considered two different structures: (i) a microstrip line loaded with pairs of stepped impedance resonators (SIRs), and (ii) a coplanar waveguide (CPW) transmission line loaded with pairs of split ring resonators (SRRs). In both cases, the line exhibits a single resonance frequency (transmission zero) if the resonators are identical (symmetric structure with regard to the line axis), and this resonance is different to the one of the line loaded with a single resonator due to inter-resonator coupling. If the structures are asymmetric, inter-resonator coupling enhances the distance between the two split resonance frequencies that arise. In spite that the considered lines and loading resonators are very different and are described by different lumped element equivalent circuit models, the phenomenology associated to the effects of coupling is exactly the same, and the resonance frequencies are given by identical expressions. The reported lumped element circuit models of both structures are validated by comparing the circuit simulations with extracted parameters with both electromagnetic simulations and experimental data. These structures can be useful for the implementation of microwave sensors based on symmetry properties. - Highlights: • Magnetic-coupling between resonant elements affects transmission properties. • Inter-resonant coupling enhances the distance of two resonant frequencies. • The structures are useful for sensors and comparators, etc.

  16. CALCULATION METHOD OF ELECTRIC POWER LINES MAGNETIC FIELD STRENGTH BASED ON CYLINDRICAL SPATIAL HARMONICS

    Directory of Open Access Journals (Sweden)

    A.V. Erisov

    2016-05-01

    Full Text Available Purpose. Simplification of accounting ratio to determine the magnetic field strength of electric power lines, and assessment of their environmental safety. Methodology. Description of the transmission lines of the magnetic field by using techniques of spatial harmonic analysis in the cylindrical coordinate system is carried out. Results. For engineering calculations of electric power lines magnetic field with sufficient accuracy describes their first spatial harmonic magnetic field. Originality. Substantial simplification of the definition of the impact of the construction of transmission line poles on the value of its magnetic field and the bands of land alienation sizes. Practical value. The environmentally friendly projection electric power lines on the level of the magnetic field.

  17. Transmission line undergrounding : rate impact investigation and analysis

    International Nuclear Information System (INIS)

    2004-01-01

    In response to concerns expressed by the residents of Markham, Ontario regarding the possible environmental and health impacts of a proposed 230 kV overhead transmission line, Hydro One Networks Inc. (HONI) has proposed to place the line underground as an alternative. This analysis was prepared to evaluate the potential impacts on transmission rates and consumer prices related to changes in the level of underground construction of transmission lines by HONI, as opposed to overhead construction. The report presents the approach to data collection; cost estimates and projections; the modeling and projecting of HONI's regulated rate base and revenue requirement on a basis that reflects the manner in which its future transmission rates are expected to be established; estimates of the incremental cost of undergrounding reflecting a range of reasonable assumptions; and a comparison of the resulting transmission costs and total customer bill. To address the issue of potential demand in other municipalities for additional undergrounding, the study also examined the cumulative effects of ten years' incremental undergrounding costs (i.e. effects on 2014 rates). It was concluded that if HONI were to implement an undergrounding program beginning in 2005, resulting in the installation of 80 km of underground lines by 2014, and shared costs by all users of HONI's system through the network transmission charges, the 2014 transmission rates would be higher. 5 tabs

  18. Transmission line fault distance and direction estimation using ...

    African Journals Online (AJOL)

    An accurate fault distance and direction estimation based on application of artificial neural networks for protection of doubly fed transmission lines is presented in this paper. The proposed method uses the voltage and current available at only the local end of line. This method is adaptive to the variation of fault location, fault ...

  19. 49 CFR 192.705 - Transmission lines: Patrolling.

    Science.gov (United States)

    2010-10-01

    ... adjacent to the transmission line right-of-way for indications of leaks, construction activity, and other factors affecting safety and operation. (b) The frequency of patrols is determined by the size of the line, the operating pressures, the class location, terrain, weather, and other relevant factors, but...

  20. Field free line magnetic particle imaging

    CERN Document Server

    Erbe, Marlitt

    2014-01-01

    Marlitt Erbe provides a detailed introduction into the young research field of Magnetic Particle Imaging (MPI) and field free line (FFL) imaging in particular. She derives a mathematical description of magnetic field generation for FFL imaging in MPI. To substantiate the simulation studies on magnetic FFL generation with a proof-of-concept, the author introduces the FFL field demonstrator, which provides the world's first experimentally generated rotated and translated magnetic FFL field complying with the requirements for FFL reconstruction. Furthermore, she proposes a scanner design of consi

  1. Design and performance analysis of transmission line-based ...

    Indian Academy of Sciences (India)

    velocity of light. Thus, the pulse width T is twice the time taken by the electromagnetic wave to travel the length of the coaxial line in the dielectric medium, i.e.. T = 2to. (3). Characteristic impedance of the transmission line is given by. Z0 = (L/C)1/2,. (4) where, L and C are the inductance and capacitance of the coaxial line per ...

  2. Electric transmission line flashover prediction system

    Science.gov (United States)

    Amarh, Felix

    Near industrial, agricultural, or coastal areas, contamination is a frequent cause of insulator flashover, most cases of which result in lengthy service interruptions. Utilities spend significant amounts of money on insulator washing and cleaning before the restoration of the service. Laboratory studies and industrial experience have shown that both contamination and wetting of insulator surfaces, which initiate the flow of leakage current, are required for insulator flashover. The leakage current leading to flashover has distinctive stages of development. Flashover is preceded by dry-band arcing and extension of the arc to bridge the insulator. This combination significantly modifies both the magnitude and shape of the leakage current. A condition-based monitoring (CBM) system that monitors the easily measurable insulator leakage current as a means of assessing pollution severity and would possibly predict an approaching flashover could prove beneficial to utilities. The overall aim of this project is the development of a system that monitors pollution build-up through the signature changes in the leakage current and alerts an operator when there is a danger of flashover. The operator can, in turn, order maintenance personnel to wash the insulators. This will safeguard against unforeseen flashovers, since the system is constantly being monitored and diagnosed. Additionally, the washing cycles of insulators will be optimized, saving money and eventually rendering the power transmission system more reliable.

  3. Development of the ITER ICH Transmission Line and Matching System

    Science.gov (United States)

    Rasmussen, D. A.; Goulding, R. H.; Pesavento, P. V.; Peters, B.; Swain, D. W.; Fredd, E. H.; Hosea, J.; Greenough, N.

    2011-10-01

    The ITER Ion Cyclotron Heating (ICH) System is designed to couple 20 MW of heating power for ion and electron heating. Prototype components for the ITER Ion Cyclotron Heating (ICH) transmission line and matching system are being designed and tested. The ICH transmission lines are pressurized 300 mm diameter coaxial lines with water-cooled aluminum outer conductor and gas-cooled and water-cooled copper inner conductor. Each ICH transmission line is designed to handle 40-55 MHz power at up to 6 MW/line. A total of 8 lines split to 16 antenna inputs on two ICH antennas. Industrial suppliers have designed coaxial transmission line and matching components and prototypes will be manufactured. The prototype components will be qualified on a test stand operating at the full power and pulse length needed for ITER. The matching system must accommodated dynamic changes in the plasma loading due to ELMS and the L to H-mode transition. Passive ELM tolerance will be performed using hybrid couplers and loads, which can absorb the transient reflected power. The system is also designed to compensate for the mutual inductances of the antenna current straps to limit the peak voltages on the antenna array elements.

  4. Atlas transmission line/transition design and fabrication status

    CERN Document Server

    Ballard, E O; Davis, H A; Elizondo, J M; Gribble, R F; Nielsen, K E; Parker, G V; Ricketts, R L; Valdez, G A

    1999-01-01

    Atlas is a pulsed-power facility under development at Los Alamos National Laboratory to drive high-energy density experiments. Design has been completed for this new generation pulsed-power machine consisting of an azimuthal array of 24, 240-kV Marx modules and transmission lines supplying current to the load region at the machine center. The transmission line consists of a cable header, load protection switch, and tri-plate assembly interfacing to the center transition section. The cable header interface to the Marx module provides a mechanism to remove the Marx module for maintenance without removing other components of the transmission line. The load protection switch provides a mechanism for protecting the load during charging of the Marx in the event of a pre-fire condition. The aluminum tri-plate is a low-inductance transmission line that carries radial current flow from the Marx energy storage system at the machine periphery toward the load. All transmission line components are oil insulated except the...

  5. Power transmission line fault location based on current traveling waves

    Energy Technology Data Exchange (ETDEWEB)

    Elhaffar, A.M.

    2008-07-01

    Transmission lines are designed to transfer electric power from source locations to distribution networks. However, their lengths are exposed to various faults. Protective relay and fault recorder systems, based on fundamental power frequency signals, are installed to isolate and the faulty line and provide the fault position. However, the error is high especially in transmission lines. This thesis investigates the problem of fault localization using traveling wave current signals obtained at a single-end of a transmission line and/or at multi-ends of a transmission network. A review of various signal processing techniques is presented. The wavelet transform is found to be more accurate than conventional signal processing techniques for extracting the traveling wave signals from field measurements. In this thesis, an optimization method has been developed to select the best wavelet candidate from several mother wavelets. The optimum mother wavelet was selected and used to analyze the fault signal at different details' levels. The best details' level, which carries the fault features, was selected according to its energy content. From the line and network data, the traveling wave speed is calculated for each line using the optimum mother wavelet at different detail levels. Accurate determination fault location depends on the proper details wavelet level as well as the propagation speed. A high frequency current transformer model has been verified experimentally using impulse current signals at the high voltage laboratory, Helsinki University of Technology. Single-end method has been studied for several transmission line configurations, including lines equipped with/without overhead ground wires, counterpoises, or overhead ground wires and counterpoises. The time difference between the aerial and ground mode has also been investigated for these line configurations. Multi-ended method, using recordings sparsely located in the transmission network, has been

  6. X-Line Retreat During Magnetic Reconnection

    Science.gov (United States)

    Oka, Mitsuo; Fujimoto, M.; Shinohara, I.

    2008-03-01

    In many astro- and space- physics situations, we observe energy release processes in vicinities of an obstacle. In the Earth's magnetotail, an Earthward plasma flow hits the magnetosphere which might end up with magnetic field pile-up and/or dipolarization of the magnetosphere. During solar flares, in view of magnetic reconnection model, a downward plasma jet collides with a magnetic flux tube at the bottom of the solar corona.In order to study energe release processes in these situations, we have set up a hard wall (symmetric boundary) to model either dipole magnetic field in the Earth's magnetosphere or magnetic loops in the solar corona. For simplicity, we have neglected any density gradient or magnetic field strucures. The initial configuration of the current sheet is therefore of a Harris-type. After initiating magnetic reconnection by a magnetic field purturbation, its time evolution is studied by means of full particle, PIC simulation.The prominent feature in our simulation is a slow motion of the X-point directing away from the wall, which we call `X-line Retreat'. Our preliminary results show retreat speed to be about 0.1 times the Alfven speed measured at the boundaries. In our talk, we will discuss the mechanism and cause of the X-line retreat as well as the structures of the diffusion region. Implication on particle acceleration will also be addressed.

  7. Experimental analysis of a TEM plane transmission line for DNA studies at 900 MHz EM fields

    International Nuclear Information System (INIS)

    Belloni, F; Doria, D; Lorusso, A; Nassisi, V; Velardi, L; Alifano, P; Monaco, C; Tala, A; Tredici, M; Raino, A

    2006-01-01

    A suitable plane transmission line was developed and its behaviour analysed at 900 MHz radiofrequency fields to study DNA mutability and the repair of micro-organisms. In this work, utilizing such a device, we investigated the behaviour of DNA mutability and repair of Escherichia coli strains. The transmission line was very simple and versatile in changing its characteristic resistance and field intensity by varying its sizes. In the absence of cell samples inside the transmission line, the relative modulation of the electric and/or magnetic field was ±31% with respect to the mean values, allowing the processing of more samples at different exposure fields in a single run. A slight decrease in spontaneous mutability to rifampicin-resistance of the E. coli JC411 strain was demonstrated in mismatch-repair proficient samples exposed to the radio-frequency fields during their growth on solid medium

  8. AA, sandwich line with magnetic horn

    CERN Document Server

    CERN PhotoLab

    1980-01-01

    The magnetic horn, focusing the antiprotons emanating from the target, was affixed to a sandwich line through which the 150 kA pulses were supplied. Expecting to have to change from time to time the fragile horn (inner conductor only 0.7 mm thick), the assembly was designed for quick exchange. At the lower end of the sandwich line we see the connectors for the high-current cables, at the upper end the magnet horn. It has just been lifted from the V-supports which held it aligned downstream of the target. Continue with 8010293.

  9. Kalman filter estimation of RLC parameters for UMP transmission line

    Directory of Open Access Journals (Sweden)

    Mohd Amin Siti Nur Aishah

    2018-01-01

    Full Text Available This paper present the development of Kalman filter that allows evaluation in the estimation of resistance (R, inductance (L, and capacitance (C values for Universiti Malaysia Pahang (UMP short transmission line. To overcome the weaknesses of existing system such as power losses in the transmission line, Kalman Filter can be a better solution to estimate the parameters. The aim of this paper is to estimate RLC values by using Kalman filter that in the end can increase the system efficiency in UMP. In this research, matlab simulink model is developed to analyse the UMP short transmission line by considering different noise conditions to reprint certain unknown parameters which are difficult to predict. The data is then used for comparison purposes between calculated and estimated values. The results have illustrated that the Kalman Filter estimate accurately the RLC parameters with less error. The comparison of accuracy between Kalman Filter and Least Square method is also presented to evaluate their performances.

  10. A Transmission Line Model for the Spherical Beltrami Problem

    Science.gov (United States)

    Papageorgiou, C. D.; Raptis, T. E.

    We extend a previously introduced model for finding eigenvalues and eigenfunctions of PDEs with a certain natural symmetry set based on an analysis of an equivalent transmission line circuit. This was previously applied with success in the case of optical fibers [8], [9] as well as in the case of a linear Schroedinger equation [10], [11] and recently in the case of spherical symmetry (Ball Lightning) [12]. We explore the interpretation of eigenvalues as resonances of the corresponding transmission line model. We use the generic Beltrami problem of non-constant eigen-vorticity in spherical coordinates as a test bed and we locate the bound states and the eigen-vorticity functions.

  11. Tuning of JET transmission line/antenna system during ICRH

    International Nuclear Information System (INIS)

    Oeberg, J.

    1993-05-01

    The launched toroidal wave spectrum for ICRH and ICRH current drive is controlled by the phasing of the antenna currents. This causes imbalance in the transmission lines, which makes it more difficult to use the full power of the ICRH generators. Further, the generators are sensitive to the amount of reflected power. To reduce the amount of reflected power the transmission lines have to be constantly tuned. To study the tuning three models of the antenna are developed and compared with experimental results. A method is suggested which enables better usage of the generated power using a power correction unit to evenly distribute the power load between the generators. 4 refs, 24 figs

  12. Lightning performance assessment of Hellenic high voltage transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Ekonomou, Lambros [Hellenic American University, 12 Kaplanon Str., 106 80 Athens (Greece); Gonos, Ioannis F.; Stathopulos, Ioannis A. [National Technical University of Athens, School of Electrical and Computer Engineering, High Voltage Laboratory, 9 Iroon Politechniou St., Zografou Campus, 157 80 Athens (Greece)

    2008-04-15

    A methodology for assessing the lightning performance of Hellenic high voltage transmission lines has been developed. Its main advantage is that the analysed transmission line is divided into regions and the analysis is conducted separately for each one region, taking into account the individual characteristics, which exist in each one of them. The developed approach intends to offer more accuracy in the assessment of lightning performance of Hellenic high voltage transmission lines and of similar lines, where they run at the same time through a plain region, a coastline and/or a mountainous region. The aims of the paper are to describe in detail the proposed methodology and to present results obtained by its application on operating Hellenic transmission lines of 150 and 400 kV. The computed results are compared with the results produced by another software tool published in the technical literature and with the real records of outage rate showing a good agreement. The presented methodology, which is coded in a comprehensive computer program, can be proved valuable to the studies of electric power systems designers intending in a more effective lightning protection. (author)

  13. Fort Peck-Wolf Point transmission line project, Montana

    International Nuclear Information System (INIS)

    1992-01-01

    The primary objective of the project is to replace the existing 36-mile Fort Peck-Wolf Point transmission line which has reached the end of its useful service life. Presently, the overall condition of this existing section of the 47-year-old line is poor. Frequent repairs have been required because of the absence of overhead ground wires. The continued maintenance of the line will become more expensive and customer interruptions will persist because of the damage due to lightning. The expense of replacing shell rotted poles, and the concern for the safety of the maintenance personnel because of hazards caused by severe shell rot are also of primary importance. The operational and maintenance problems coupled with power system simulation studies, demonstrate the need for improvements to the Wolf Point area to serve area loads. Western's Wolf Point Substation is an important point of interconnection for the power output from the Fort Peck Dam to area loads as far away as Williston, North Dakota. The proposed transmission line replacement would assure that there will continue to be reliable transmission capacity available to serve area electrical loads, as well as provide a reliable second high-voltage transmission path from the Fort Peck generation to back-up a loss of the Fort Peck-Wolf Point 115-kV Line No. 1

  14. Design considerations of translmission line superconductors for fast-cycling accelerator magnets

    Energy Technology Data Exchange (ETDEWEB)

    Piekarz, H.; /Fermilab

    2008-07-01

    Novel design options of HTS and LTS superconductor lines for fast-cycling accelerator magnets are presented. The cryogenic power losses in using these conductors in transmission line application to energize the accelerator magnet string are discussed. A test arrangement to measure power loss of the proposed superconductor lines operating up to 2 T/s ramp rate and 0.5 Hz repetition cycle is described.

  15. Calculation of the Magnetic Fields of the Electric Power Line

    Directory of Open Access Journals (Sweden)

    Patsiuk V.

    2016-12-01

    Full Text Available The task of calculation of per unit length parameters of multi-conductor electrical overhead transmission lines has been treated in the paper. The calculation of distribution of electric and magnetic fields has been performed by means of the finite volume method for entire span of the line. The theoretical justification of the method for calculation the parameters of electromagnetic field taking into account the change of the vector of magnetic potential along the line has been given. The problems of electrostatic and magnetostatic for a single electric conductor and unlimited long conductor with current have been solved. For the inner and total inductivities of a single conductor under the current have been obtained relationships and drawn dependences. Dependence between the speeds of light and of electromagnetic wave’s propagation has been presented. Based on the characteristics of distribution of electric and magnetic fields of multi-conductor lines has been provided the method of calculation of the matrix of own and mutual capacitances and inductivities the calculated values of per unit length parameters of compact 110 kV electric line which is in concordance with one of basic physical constant – the speed of light.

  16. Visual impact of overhead power transmission lines and dielectric and corona effects constraints on insulation coordination

    International Nuclear Information System (INIS)

    Deponti, F.; Fini, G.P.; Porrino, A.; Rosa, F.

    1992-06-01

    In assessing overhead power transmission line design and planning criteria for the optimization of visual impact, safety and the reduction of electro magnetic disturbance effects, this paper reviews the research findings of ENEL, the Italian Electricity Board. The on-going research activities involve theoretical calculations and laboratory performance tests to determine the best compact configurations for 380 kV lines. The parameters under examination include: insulator spacing, sizing and salt fog resistivity; allowable overvoltages; maximum line length; behaviour in lightning conditions; radio and acoustics disturbances

  17. Environmental impact of high voltage aerial transmission lines

    International Nuclear Information System (INIS)

    Silva, R.P.; Mouallen, M.C.; Quintella, S.E.A.

    1989-01-01

    The identification of environmental impacts caused by the aerial transmission lines and the measures for reducing these impacts are discussed, considering the impact over the soil in different areas, biological effects caused by delayed exposure and visual impacts due to the line structures. A methodology for the impact evaluation and the aspects of the Environmental Impact Studies and Environmental Impact Report are also studied. (C.G.C.). 2 refs, 1 fig

  18. Recent techniques used in transmission line protection: a review

    African Journals Online (AJOL)

    user

    Power Apparatus and Systems, vol.PAS-91, no.3, pp. 1235-1243. Girgis A.A., Hart D.G. and Peterson W.L., 1992. Fault location in transmission lines using two and three terminal lines, IEEE. Trans. Power Delivery, vol.7, no.1, pp. 98-107. Girgis A.A., Sallam A.A. and Karim El-Din A., 1998. An adaptive protection scheme for ...

  19. New circuit theory of multiconductor transmission lines resulting from a new practice of noise reduction.

    Science.gov (United States)

    Toki, Hiroshi; Sato, Kenji

    2014-01-01

    In modern life, we are surrounded by and filled with electromagnetic noise caused by the dominant use of energy in the form of electricity. This situation is brought about by the fact that the noise is not understood theoretically. A new practice of noise reduction was introduced for the construction of Heavy Ion Medical Accelerator in Chiba (HIMAC). The key concept is a symmetric three-line circuit that arranges power supplies, noise filters and magnets around a third central ground line. A continuous theoretical effort forced us to find a new circuit theory involving a multiconductor transmission-line system starting from Maxwell's equations without any approximation. We discuss the essence of all of these experimental and theoretical developments with the hope to remove unnecessary electromagnetic noise not only from power supplies, but also from all electric devices. The newly derived circuit theory of multiconductor transmission lines is universal, and establishes the validity of the practice of noise reduction.

  20. Transmission expansion in Argentina 2: The Fourth Line revisited

    Energy Technology Data Exchange (ETDEWEB)

    Littlechild, Stephen C. [Judge Business School, Trumpington Street, Cambridge CB2 1AG (United Kingdom); Skerk, Carlos J. [Mercados Energeticos, Buenos Aires (Argentina)

    2008-07-15

    In 1992, Argentina introduced the Public Contest method, which required transmission users to propose, vote and pay for major expansions of the electricity transmission system. Economists, consultants, the regulator and others held the application of this method to be unsuccessful, mainly on the ground that 'for many years' it delayed investment in a 'much needed' Fourth Line to Buenos Aires. The commentators blamed externalities, free-rider problems, the Area of Influence method used to define voting rights, and transactions costs. This paper re-examines the history and economics of the Fourth Line. The delay to the Fourth Line was short (a year and a half rather than many years) and enabled a significant reduction in construction costs. Externalities, free-riding, the Area of Influence method and transactions costs were not problematic. The Fourth Line was initially rejected because it was unprofitable to key beneficiaries. Far from being much needed, the Fourth Line was not economic because the congestion it avoided was worth less than the cost of building it. It had become more economic to transport gas to generate electricity near Buenos Aires than to transmit electricity over long distances. The location of subsequent power stations reflected this. Even though the presence of a subsidy meant that the Public Contest method did not prevent the building of the Fourth Line, it nonetheless forced a much-needed reappraisal of traditional transmission investment policy. (author)

  1. Conductance of auroral magnetic field lines

    International Nuclear Information System (INIS)

    Weimer, D.R.; Gurnett, D.A.; Goertz, C.K.

    1986-01-01

    DE-1 high-resolution double-probe electric-field data and simultaneous magnetic-field measurements are reported for two 1981 events with large electric fields which reversed over short distances. The data are presented graphically and analyzed in detail. A field-line conductance of about 1 nmho/sq m is determined for both upward and downward currents, and the ionospheric conductivity is shown, in the short-wavelength limit, to have little effect on the relationship between the (N-S) electric and (E-W) magnetic fields above the potential drop parallel to the magnetic-field lines. The results are found to be consistent with a linear relationship between the field-aligned current density and the parallel potential drop. 14 references

  2. Canby Area Service Project substation and associated transmission line

    International Nuclear Information System (INIS)

    1992-02-01

    Bonneville Power Administration (BPA) provides power to Surprise Valley Electrification Corporation (SVEC) in Modoc County, California. BPA uses PacificCorp's substation and transmission facilities between Alturas and Canby, California to transfer power to SVEC's Canby Substation. In the next year, SVEC expects increased industrial, agricultural, and residential electric loads on their 69-kV transmission system south of Canby. SVEC's substation can accommodate only about 10 percent of the expected additional electric load. BPA's proposed action is intended to meet SVEC's increasing electric load. BPA proposes to meet SVEC's increasing energy load by tapping into BPA's existing BPA Malin-Warner 230-kV transmission line, and building an 7.9-mile transmission line to a new BPA substation. BPA proposes to build the new substation next to the west side of SVEC's Canby Substation (Figure 1). This new substation will allow SVEC to move the additional power over their existing transmission or distribution lines. This report is the environmental assessment of the potential impact of the proposed project. The assessment determined that no ''environmental impact statement'' is not required

  3. Study on the Extremely Low Frequency (ELF) Electromagnetic Field (EMF) emission from overhead High-Voltage Transmission Lines

    International Nuclear Information System (INIS)

    Parthasarathy, S.R.; Roha Tukimin; Wan Saffiey Wan Abdullah; Zulkifli Yusof; Mohd Azizi Mohd Jali

    2016-01-01

    The paper highlights the study on the Extremely Low Frequency (ELF) Electromagnetic Field (EMF) emission performed at an overhead 275-kV High-Voltage Transmission Lines. The study comprised of assessment at the transmission lines on 3 different cases and locations in Klang Valley, specifically on a vacant land near the transmission line, inside and around the house at the vicinity of the transmission line and the area directly under the transmission line. The instrument setup and measurement protocols during the assessment were adopted from standard measurement method and procedures stipulated under the Institute of Electrical and Electronics Engineers (IEEE) Standard. The results were compared with the standards recommended in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. The results showed that the measured field strengths are within the safety limit with the highest measured exposure was 10.8 % and 1.8 % of the permissible exposure limit for the electric and magnetic field respectively. Both the field strengths were found to drop significantly against distance from the transmission lines where closer distances showed higher field strengths. Furthermore, the study revealed that buildings and other object such as trees and shrubs screen out the electric field, resulting in a lower value at indoor measurements and near the stated objects. In addition, higher value of electric and magnetic field strengths were recorded when assessment was being done directly under the transmission line compared to the lateral measurement. (author)

  4. Interpretation of corrosion impedance data using transmissions lines

    International Nuclear Information System (INIS)

    Polo Sanz, J. L.; Bastidas Rull, J. M.

    2000-01-01

    The transmission lines most frequently used in corrosion studies are described. Electrodes constituted by cylindrical pores and with irregular shapes are discussed. Coplanar electrodes are also studied. Finally, topologies of networks with fractional power frequently dependence are commented. (Author) 29 refs

  5. The EC H&CD Transmission Line for ITER

    NARCIS (Netherlands)

    Gandini, F.; Bigelow, T. S.; Becket, B.; Caughman, J. B.; Cox, D.; Darbos, C.; Gassmann, T.; Henderson, M. A.; Jean, O.; Kajiwara, K.; Kobayashi, N.; Nazare, C.; Oda, Y.; Omori, T.; Purohit, D.; Rasmussen, D. A.; Ronden, D. M. S.; Saibene, G.; Sakamoto, K.; Shapiro, M. A.; Takahashi, K.; Temkin, R. J.

    2011-01-01

    The transmission line (TL) subsystem associated with the ITER electron cyclotron heating and current drive system has reached the conceptual design maturity. At this stage the responsibility of finalizing the design has been transferred from the ITER Organization to the U.S. Domestic Agency. The

  6. Recent techniques used in transmission line protection: A review ...

    African Journals Online (AJOL)

    include almost all the techniques and philosophies of transmission line protection reported in the literature up to October 2010. The focus of this article is on the most recent techniques, like artificial neural network, fuzzy logic, fuzzy-neuro, fuzzy logicwavelet based and phasor measurement unit-based concepts as well as ...

  7. 75 FR 66750 - Albany-Eugene Transmission Line Rebuild Project

    Science.gov (United States)

    2010-10-29

    ... Project AGENCY: Bonneville Power Administration (BPA), Department of Energy (DOE). ACTION: Notice of... public scoping process for the Albany-Eugene Transmission Line Rebuild Project EIS and requesting... proposed project. DATES: Written comments are due to the address below no later than November 30, 2010...

  8. Proximity effects of high voltage electric power transmission lines on ...

    African Journals Online (AJOL)

    Yomi

    2010-08-18

    Aug 18, 2010 ... The proximity effects of high voltage electric power transmission lines on Leyland Cypress. (xCupressocyparis leylandii (Dallim. and A.B. Jacks.) Dallim) and Japanese Privet (Ligustrum japonicum. Thunb.) growth were examined in a private nursery located in Sakarya, Turkey. Five transect were randomly ...

  9. 49 CFR 192.485 - Remedial measures: Transmission lines.

    Science.gov (United States)

    2010-10-01

    ... transmission line with general corrosion and with a remaining wall thickness less than that required for the... of the pipe based on actual remaining wall thickness. However, corroded pipe may be repaired by a method that reliable engineering tests and analyses show can permanently restore the serviceability of...

  10. Proximity effects of high voltage electric power transmission lines on ...

    African Journals Online (AJOL)

    The proximity effects of high voltage electric power transmission lines on Leyland Cypress (xCupressocyparis leylandii (Dallim. and A.B. Jacks.) Dallim) and Japanese Privet (Ligustrum japonicum Thunb.) growth were examined in a private nursery located in Sakarya, Turkey. Five transect were randomly chosen in both ...

  11. Rigorous theoretical derivation of lumped models to transmission line systems

    International Nuclear Information System (INIS)

    Zhao Jixiang

    2012-01-01

    By virtue of the negative electric parameter concept, i.e. negative lumped resistance, inductance, conductance and capacitance (N-RLGC), the lumped equivalent models of transmission line systems, including the circuit model, two-port π-network and T-network, are given. We start from the N-segment-ladder-like equivalent networks composed distributed parameters, and achieve the input impedance in the form of a continued fraction. Utilizing the continued fraction theory, the expressions of input impedance are obtained under three kinds of extreme cases, i.e. the load impedances are equal to zero, infinity and characteristic impedance, respectively. When the number of segment N is limited to infinity, they are transformed to lumped elements. Comparison between the distributed model and lumped model of transmission lines, the expression of tanh γd, which is the key term in the transmission line equations, are obtained by RLGC, furthermore, according to input admittance, admittance matrix and ABCD matrix of transmission lines, the lumped equivalent circuit models, π-networks and T-networks have been given. The models are verified in the frequency and time domain, respectively, showing that the models are accurate and efficient. (semiconductor integrated circuits)

  12. Design and performance analysis of transmission line-based ...

    Indian Academy of Sciences (India)

    transformations. They are also relatively inexpensive and easy to replace in the event of breakdown. Charging of the coaxial transmission line is done using 100W SMPS powered by. 24V DC Panasonic batteries, which makes the system portable. It converts the DC input to. 50 kV/2 mA as output. The total weight of power ...

  13. A novel transmission line protection using DOST and SVM

    Directory of Open Access Journals (Sweden)

    M. Jaya Bharata Reddy

    2016-06-01

    Full Text Available This paper proposes a smart fault detection, classification and location (SFDCL methodology for transmission systems with multi-generators using discrete orthogonal Stockwell transform (DOST. The methodology is based on synchronized current measurements from remote telemetry units (RTUs installed at both ends of the transmission line. The energy coefficients extracted from the transient current signals due to occurrence of different types of faults using DOST are being utilized for real-time fault detection and classification. Support vector machine (SVM has been deployed for locating the fault distance using the extracted coefficients. A comparative study is performed for establishing the superiority of SVM over other popular computational intelligence methods, such as adaptive neuro-fuzzy inference system (ANFIS and artificial neural network (ANN, for more precise and reliable estimation of fault distance. The results corroborate the effectiveness of the suggested SFDCL algorithm for real-time transmission line fault detection, classification and localization.

  14. Airplane Ice Detector Based on a Microwave Transmission Line

    Science.gov (United States)

    Ngo, Phong; Arndt, G. Dickey; Carl, James R.

    2004-01-01

    An electronic instrument that could detect the potentially dangerous buildup of ice on an airplane wing is undergoing development. The instrument is based on a microwave transmission line configured as a capacitance probe: at selected spots, the transmission-line conductors are partly exposed to allow any ice and/or liquid water present at those spots to act as predominantly capacitive electrical loads on the transmission line. These loads change the input impedance of the transmission line, as measured at a suitable excitation frequency. Thus, it should be possible to infer the presence of ice and/or liquid water from measurements of the input impedance and/or electrical parameters related to the input impedance. The sensory transmission line is of the microstrip type and thus thin enough to be placed on an airplane wing without unduly disturbing airflow in flight. The sensory spots are small areas from which the upper layer of the microstrip has been removed to allow any liquid water or ice on the surface to reach the transmission line. The sensory spots are spaced at nominal open-circuit points, which are at intervals of a half wavelength (in the transmission line, not in air) at the excitation frequency. The excitation frequency used in the experiments has been 1 GHz, for which a half wavelength in the transmission line is .4 in. (.10 cm). The figure depicts a laboratory prototype of the instrument. The impedance-related quantities chosen for use in this version of the instrument are the magnitude and phase of the scattering parameter S11 as manifested in the in-phase (I ) and quadrature (Q) outputs of the phase detector. By careful layout of the transmission line (including the half-wavelength sensor spacing), one can ensure that the amplitude and phase of the input to the phase detector keep shifting in the same direction as ice forms on one or more of the sensor areas. Although only one transmission-line sensor strip is used in the laboratory version, in a

  15. Theory and Circuit Model for Lossy Coaxial Transmission Line

    Energy Technology Data Exchange (ETDEWEB)

    Genoni, T. C.; Anderson, C. N.; Clark, R. E.; Gansz-Torres, J.; Rose, D. V.; Welch, Dale Robert

    2017-04-01

    The theory of signal propagation in lossy coaxial transmission lines is revisited and new approximate analytic formulas for the line impedance and attenuation are derived. The accuracy of these formulas from DC to 100 GHz is demonstrated by comparison to numerical solutions of the exact field equations. Based on this analysis, a new circuit model is described which accurately reproduces the line response over the entire frequency range. Circuit model calculations are in excellent agreement with the numerical and analytic results, and with finite-difference-time-domain simulations which resolve the skindepths of the conducting walls.

  16. Large field-of-view transmission line resonator for high field MRI

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Johannesson, Kristjan Sundgaard; Boer, Vincent

    2016-01-01

    Transmission line resonators is often a preferable choice for coils in high field magnetic resonance imaging (MRI), because they provide a number of advantages over traditional loop coils. The size of such resonators, however, is limited to shorter than half a wavelength due to high standing wave...... ratio, which leads to inhomogeneous field distribution along the resonator. In this work, it is demonstrated that the resonator length can be extended to over half a wavelength with the help of series capacitors. The approach allows for reduced standing wave ratio and improved field homogeneity....... Achieved magnetic field distribution is compared to the conventional transmission line resonator. Imaging experiments are performed using 7 Tesla MRI system. The developed resonator is useful for building coils with large field-of-view....

  17. Research on the Test of Transmission Line Galloping

    Science.gov (United States)

    Zhang, Lichun; Li, Qing; lv, Zhongbin; Ji, Kunpeng; Liu, Bin

    2018-03-01

    The load of iced transmission line and the load generated by galloping after the conductor are covered by ice all may cause severe circuit faults, such as tripping, conductor breaking, armor clamp damage and even tower collapse, thus severely threatening running safety of power system. The generation and development processes of galloping of power transmission line is very complicated, and numerous factors may influence the galloping excitation, such as environmental factors, terrain factors and structural parameters of power transmission line; in which, the ice covering of conductor is one of necessary factors causing galloping. Therefore, researches on ice covering increasing test of different types of conductors under different meteorological conditions have been conducted in large-sized multi-functional phytotron, thus obtaining the relation curve of ice covering increasing of conductor along with time under different conditions, and analyzing factors influencing increasing of ice covering. The research result shows that under the same ice covering conditions, the increasing of ice covering of conductor with small diameter is relatively rapid; both environmental temperature and wind speed have obvious influence on increasing of ice covering of conductor, and the environmental temperature will decide the type of ice covering of conductor surface. Meanwhile, after wind tunnel tests targeting conductors with different ice covering shapes, pneumatic stability loss characteristics of conductors with different ice shapes have been obtained. Research results have important scientific reference value for revealing the mechanism of galloping of iced power transmission line, and have relatively high engineering practicability value for promoting realization of early warning system for galloping of iced power transmission line.

  18. Analytical Model for High Impedance Fault Analysis in Transmission Lines

    Directory of Open Access Journals (Sweden)

    S. Maximov

    2014-01-01

    Full Text Available A high impedance fault (HIF normally occurs when an overhead power line physically breaks and falls to the ground. Such faults are difficult to detect because they often draw small currents which cannot be detected by conventional overcurrent protection. Furthermore, an electric arc accompanies HIFs, resulting in fire hazard, damage to electrical devices, and risk with human life. This paper presents an analytical model to analyze the interaction between the electric arc associated to HIFs and a transmission line. A joint analytical solution to the wave equation for a transmission line and a nonlinear equation for the arc model is presented. The analytical model is validated by means of comparisons between measured and calculated results. Several cases of study are presented which support the foundation and accuracy of the proposed model.

  19. Capacitive Coupling in Double-Circuit Transmission Lines

    Directory of Open Access Journals (Sweden)

    Zdenka Benesova

    2004-01-01

    Full Text Available The paper describes an algorithm for calculation of capacitances and charges on conductors in systems with earth wires and in double-circuit overhead lines with respect to phase arrangement. A balanced voltage system is considered. A suitable transposition of individual conductors enables to reduce the electric and magnetic fields in vicinity of overhead lines and to limit the inductive and capacitive linkage. The procedure is illustrated on examples the results of which lead to particular recommendations for designers.

  20. Bird's eye views earth's magnetic lines

    OpenAIRE

    Trulove, Susan

    2004-01-01

    Migratory birds, as well as many other animals, are able to sense the magnetic field of the earth, but how do they do it? "A fascinating possibility is that they may actually see the earth's magnetic lines as patterns of color or light intensity superimposed on their visual surroundings," said John B. Phillips, associate professor of biology in the College of Science at Virginia Tech. The results of more than two decades of research allow him to let such an image cross his mind.

  1. Wireless Sensor Network for Electric Transmission Line Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Alphenaar, Bruce

    2009-06-30

    Generally, federal agencies tasked to oversee power grid reliability are dependent on data from grid infrastructure owners and operators in order to obtain a basic level of situational awareness. Since there are many owners and operators involved in the day-to-day functioning of the power grid, the task of accessing, aggregating and analyzing grid information from these sources is not a trivial one. Seemingly basic tasks such as synchronizing data timestamps between many different data providers and sources can be difficult as evidenced during the post-event analysis of the August 2003 blackout. In this project we investigate the efficacy and cost effectiveness of deploying a network of wireless power line monitoring devices as a method of independently monitoring key parts of the power grid as a complement to the data which is currently available to federal agencies from grid system operators. Such a network is modeled on proprietary power line monitoring technologies and networks invented, developed and deployed by Genscape, a Louisville, Kentucky based real-time energy information provider. Genscape measures transmission line power flow using measurements of electromagnetic fields under overhead high voltage transmission power lines in the United States and Europe. Opportunities for optimization of the commercial power line monitoring technology were investigated in this project to enable lower power consumption, lower cost and improvements to measurement methodologies. These optimizations were performed in order to better enable the use of wireless transmission line monitors in large network deployments (perhaps covering several thousand power lines) for federal situational awareness needs. Power consumption and cost reduction were addressed by developing a power line monitor using a low power, low cost wireless telemetry platform known as the ''Mote''. Motes were first developed as smart sensor nodes in wireless mesh networking applications

  2. Low-Loss Transmission Lines for High-Power Terahertz Radiation.

    Science.gov (United States)

    Nanni, Emilio A; Jawla, Sudheer K; Shapiro, Michael A; Woskov, Paul P; Temkin, Richard J

    2012-07-01

    Applications of high-power Terahertz (THz) sources require low-loss transmission lines to minimize loss, prevent overheating and preserve the purity of the transmission mode. Concepts for THz transmission lines are reviewed with special emphasis on overmoded, metallic, corrugated transmission lines. Using the fundamental HE(11) mode, these transmission lines have been successfully implemented with very low-loss at high average power levels on plasma heating experiments and THz dynamic nuclear polarization (DNP) nuclear magnetic resonance (NMR) experiments. Loss in these lines occurs directly, due to ohmic loss in the fundamental mode, and indirectly, due to mode conversion into high order modes whose ohmic loss increases as the square of the mode index. An analytic expression is derived for ohmic loss in the modes of a corrugated, metallic waveguide, including loss on both the waveguide inner surfaces and grooves. Simulations of loss with the numerical code HFSS are in good agreement with the analytic expression. Experimental tests were conducted to determine the loss of the HE(11) mode in a 19 mm diameter, helically-tapped, three meter long brass waveguide with a design frequency of 330 GHz. The measured loss at 250 GHz was 0.029 ± 0.009 dB/m using a vector network analyzer approach and 0.047 ± 0.01 dB/m using a radiometer. The experimental results are in reasonable agreement with theory. These values of loss, amounting to about 1% or less per meter, are acceptable for the DNP NMR application. Loss in a practical transmission line may be much higher than the loss calculated for the HE(11) mode due to mode conversion to higher order modes caused by waveguide imperfections or miter bends.

  3. Transmission capability of asymmetric digital subscriber lines in Taiwan

    Science.gov (United States)

    Wei, Shyue-Win; Leu, Shyue-Tzong; Wei, Che-Ho

    1995-04-01

    The transmission capacity of discrete multitone (DMT) modulation system for Taiwan's subscriber loops is evaluated in this study. Based on the characteristics of Taiwan's local loops, the transmission capacity is estimated to be 1.544 Mb/s and 6 Mb/s in Taiwan. Simulation results also show how many percents of users in Taiwan may have 1.544 Mb/s or 6 Mb/s of asymmetric digital subscriber lines (ADSL) services. Self far-end crosstalk (FEXT) and additive white Gaussian noise (AWGN) are considered to be the dominant noise sources in the work.

  4. Analyzing the Health Risks Resulting from Extending the 400kV High Voltage Transmission Lines on the Human

    Directory of Open Access Journals (Sweden)

    Mohammed Hassan Dervish

    2018-01-01

    Full Text Available Although it is difficult to imagine life without electricity, there are compiling confirmations show thatexposure to magnetic fields correlated electricity and radio frequencies pose magnificent hazards to human health. The most economist method to transfer electricity from power generation stations to users is by measures of high power transmission lines, buoyed by big transmission towers. The cables laced between the towers radiate magnetic and electric fields. In this research study, the magnetic field at ground level under 400 kV network lines extended in residential places have been conducted in two ways, mathematical calculation and practical measurement then the obtained results analyzed and compared with the international standards reference values. the reason of chose this type of transmission line is frequently using. The results indicate that they fall within the safe limiter commended by the WorldHealth Organization. the strength of radiation increasing with high of sea level and moisture ratiobecause of air ionization.

  5. Comparative study of aerial transmission lines and underground isolated on gas

    International Nuclear Information System (INIS)

    Quesada Jimenez, Marco Esteban

    2012-01-01

    A comparison was made of aerial power lines and underground isolated on gas. Growing electric demand has given way to debate the lines transmission. Multiple discussions have generated about its application, however, the energy must be supplied and this process leads to the search for more efficient methods. The theory has covered the most important design criteria of the airlines and an introduction to the little known transport lines isolated on gas. The process of manufacturing, installation and operation are studied within the scope of the project. Count information is included in the main aspects of calculation relating to power transmission. Besides, the planning of the optimal route nominal calculations, load flow and power losses are focused as well as magnetic field strengths and finally economic analysis. (author) [es

  6. Transmission Delay Modeling of Packet Communication over Digital Subscriber Line

    Directory of Open Access Journals (Sweden)

    Jiri Vodrazka

    2013-01-01

    Full Text Available Certain multimedia and voice services, such as VoIP, IPTV, etc., are significantly delay sensitive and their performance is influenced by the overall transmission delay and its variance. One of the most common solutions used in access networks are xDSL lines, especially ADSL2+ or VDSL2. Although these subscriber lines also use packet communication, there are several differences and mechanisms, which influence their resulting delay. Their delay characteristics are also dependent on the individual settings of each xDSL provider, therefore we decided to investigate this area for typical commercially available lines in Czech Republic. Based on the measured values and experiments with real ADSL2+ lines we also developed a potential modeling method, which is presented in this article as well. The parameters for packet jitter based on the generalized Pareto distribution were modeled.

  7. 7 CFR 1726.76 - Substation and transmission line materials and equipment.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Substation and transmission line materials and... Substation and Transmission Facilities § 1726.76 Substation and transmission line materials and equipment. (a... $500,000 and for all materials. (b) Standards and specifications. Substation and transmission line...

  8. Low-Loss Transmission Lines for High-Power Terahertz Radiation

    OpenAIRE

    Nanni, Emilio A.; Jawla, Sudheer K.; Shapiro, Michael A.; Woskov, Paul P.; Temkin, Richard J.

    2012-01-01

    Applications of high-power Terahertz (THz) sources require low-loss transmission lines to minimize loss, prevent overheating and preserve the purity of the transmission mode. Concepts for THz transmission lines are reviewed with special emphasis on overmoded, metallic, corrugated transmission lines. Using the fundamental HE11 mode, these transmission lines have been successfully implemented with very low-loss at high average power levels on plasma heating experiments and THz dynamic nuclear p...

  9. Fiber optic transmission line stabilization apparatus and method

    Science.gov (United States)

    Lutes, G. F., Jr.; Lau, K. Y. (Inventor)

    1981-01-01

    A reference signal of RF frequency modulates a 0.85 micrometer wavelength optical transmitter. The output of which passes through a first optical filter and a voltage-controller phase shifter. The output of the phase shifter is provided to the fiber optic transmission line. At the receiving end of the transmission line, the signal is demodulated and used to modulate a 1.06 micrometer optical transmitter. The signal from the transmitter is provided to the fiber optic transmission line and passes through the voltage-controlled phase shifter to a phase error detector. The phase of the modulation of the 1.06 micrometer wavelength signal is compared to the phase of the reference signal by the phase error detector. A phase control signal related to the phase difference is provided to the voltage controlled phase shifter which alters the phase of both optical signals until a predetermined phase relationship between modulation on the 1.06 micrometer signal and the reference signal is obtained.

  10. Development of Live-working Robot for Power Transmission Lines

    Science.gov (United States)

    Yan, Yu; Liu, Xiaqing; Ren, Chengxian; Li, Jinliang; Li, Hui

    2017-07-01

    Dream-I, the first reconfigurable live-working robot for power transmission lines successfully developed in China, has the functions of autonomous walking on lines and accurately positioning. This paper firstly described operation task and object of the robot; then designed a general platform, an insulator replacement end and a drainage plate bolt fastening end of the robot, presented a control system of the robot, and performed simulation analysis on operation plan of the robot; and finally completed electrical field withstand voltage tests in a high voltage hall as well as online test and trial on actual lines. Experimental results show that by replacing ends of manipulators, the robot can fulfill operation tasks of live replacement of suspension insulators and live drainage plate bolt fastening.

  11. Cyber Risk Assessment of Transmission Lines in Smart Grids

    Directory of Open Access Journals (Sweden)

    Xuan Liu

    2015-12-01

    Full Text Available The increasing use of information technologies in power systems has increased the risk of power systems to cyber-attacks. In this paper, we assess the risk of transmission lines being overloaded due to cyber-based false data injection attacks. The cyber risk assessment is formulated as bilevel optimization problems that determine the maximum line flows under false data injection attacks. We propose efficient techniques to reduce the computation complexity of solving the bilevel problems. Specifically, primary and secondary filtering techniques are employed to identify the lines whose flows will never exceed their limits, which can significantly reduce computation burden. A special feasibility cut-based acceleration technique is introduced to further reduce the computation burden. The simulation results on the IEEE 30-bus, IEEE 118-bus, IEEE 300-bus and IEEE 2383-bus systems verify the proposed risk assessment model and the effectiveness of the proposed filtering and acceleration techniques.

  12. Chameleon's behavior of modulable nonlinear electrical transmission line

    Science.gov (United States)

    Togueu Motcheyo, A. B.; Tchinang Tchameu, J. D.; Fewo, S. I.; Tchawoua, C.; Kofane, T. C.

    2017-12-01

    We show that modulable discrete nonlinear transmission line can adopt Chameleon's behavior due to the fact that, without changing its appearance structure, it can become alternatively purely right or left handed line which is different to the composite one. Using a quasidiscrete approximation, we derive a nonlinear Schrödinger equation, that predicts accurately the carrier frequency threshold from the linear analysis. It appears that the increasing of the linear capacitor in parallel in the series branch induced the selectivity of the filter in the right-handed region while it increases band pass filter in the left-handed region. Numerical simulations of the nonlinear model confirm the forward wave in the right handed line and the backward wave in the left handed one.

  13. Fiber Bragg Grating Sensor for Fault Detection in Radial and Network Transmission Lines

    Directory of Open Access Journals (Sweden)

    Mehdi Shadaram

    2010-10-01

    Full Text Available In this paper, a fiber optic based sensor capable of fault detection in both radial and network overhead transmission power line systems is investigated. Bragg wavelength shift is used to measure the fault current and detect fault in power systems. Magnetic fields generated by currents in the overhead transmission lines cause a strain in magnetostrictive material which is then detected by Fiber Bragg Grating (FBG. The Fiber Bragg interrogator senses the reflected FBG signals, and the Bragg wavelength shift is calculated and the signals are processed. A broadband light source in the control room scans the shift in the reflected signal. Any surge in the magnetic field relates to an increased fault current at a certain location. Also, fault location can be precisely defined with an artificial neural network (ANN algorithm. This algorithm can be easily coordinated with other protective devices. It is shown that the faults in the overhead transmission line cause a detectable wavelength shift on the reflected signal of FBG and can be used to detect and classify different kind of faults. The proposed method has been extensively tested by simulation and results confirm that the proposed scheme is able to detect different kinds of fault in both radial and network system.

  14. Fiber Bragg Grating sensor for fault detection in radial and network transmission lines.

    Science.gov (United States)

    Moghadas, Amin A; Shadaram, Mehdi

    2010-01-01

    In this paper, a fiber optic based sensor capable of fault detection in both radial and network overhead transmission power line systems is investigated. Bragg wavelength shift is used to measure the fault current and detect fault in power systems. Magnetic fields generated by currents in the overhead transmission lines cause a strain in magnetostrictive material which is then detected by Fiber Bragg Grating (FBG). The Fiber Bragg interrogator senses the reflected FBG signals, and the Bragg wavelength shift is calculated and the signals are processed. A broadband light source in the control room scans the shift in the reflected signal. Any surge in the magnetic field relates to an increased fault current at a certain location. Also, fault location can be precisely defined with an artificial neural network (ANN) algorithm. This algorithm can be easily coordinated with other protective devices. It is shown that the faults in the overhead transmission line cause a detectable wavelength shift on the reflected signal of FBG and can be used to detect and classify different kind of faults. The proposed method has been extensively tested by simulation and results confirm that the proposed scheme is able to detect different kinds of fault in both radial and network system.

  15. Magnetorheological torque transmission devices with permanent magnets

    Science.gov (United States)

    Böse, H.; Gerlach, T.; Ehrlich, J.

    2013-02-01

    A novel type of magnetorheological (MR) clutch whose magnetic circuit contains a combination of a permanent magnet and an electromagnet is described. Without the support of the electromagnet, the permanent magnet generates a magnetic field in the MR fluid shear gap which enables the MR clutch to transmit a torque without the supply of any electric energy. Hence, the operational states of this clutch are reversed with respect to the common MR clutches equipped with an electromagnet only. Three different MR clutches with hybrid magnetic circuits containing permanent magnet and electromagnet were designed, manufactured and tested. The three clutches differ in their number of mechanical parts which can rotate with respect to each other as well as in their size and weight and in their maximum transmittable torque. The largest MR clutch is capable to transmit torques up to nearly 800 Nm. The designs of the three novel MR clutches and the results of the mechanical tests upon variation of the coil current are presented in this paper.

  16. Coupling mid-infrared light from a photonic crystal waveguide to metallic transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Blanco-Redondo, Andrea, E-mail: andrea.blanco@tecnalia.com, E-mail: r.hillenbrand@nanogune.eu [ICT-European Software Institute Division, Tecnalia, Ibaizabal Bidea, Ed. 202, 48170 Zamudio, Bizkaia (Spain); Dpto. Electronica y Telecom., E.T.S. Ingeniería Bilbao, UPV/EHU, Alda. Urquijo, 48103 Bilbao, Bizkaia (Spain); Sarriugarte, Paulo [Nanooptics Group, CIC nanoGUNE Consolider, 20018 Donostia–San Sebastian, Gipuzkoa (Spain); Garcia-Adeva, Angel [Dpto. Fisica Aplicada I, E.T.S. Ingeniería de Bilbao, UPV-EHU, Alda. Urquijo, 48103 Bilbao, Bizkaia (Spain); Zubia, Joseba [Dpto. Electronica y Telecom., E.T.S. Ingeniería Bilbao, UPV/EHU, Alda. Urquijo, 48103 Bilbao, Bizkaia (Spain); Hillenbrand, Rainer, E-mail: andrea.blanco@tecnalia.com, E-mail: r.hillenbrand@nanogune.eu [Nanooptics Group, CIC nanoGUNE Consolider, 20018 Donostia–San Sebastian, Gipuzkoa (Spain); IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Bizkaia (Spain)

    2014-01-06

    We propose and theoretically study a hybrid structure consisting of a photonic crystal waveguide (PhC-wg) and a two-wire metallic transmission line (TL), engineered for efficient transfer of mid-infrared (mid-IR) light between them. An efficiency of 32% is obtained for the coupling from the transverse magnetic (TM) photonic mode to the symmetric mode of the TL, with a predicted intensity enhancement factor of 53 at the transmission line surface. The strong coupling is explained by the small phase velocity mismatch and sufficient spatial overlapping between the modes. This hybrid structure could find applications in highly integrated mid-IR photonic-plasmonic devices for biological and gas sensing, among others.

  17. Fault diagnosis system for tapped power transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed, E.A.; Talaat, H.A. [Elect. Power and Machines Dept., Ain Shams Univ., Cairo (Egypt); Khamis, E.A. [EEA, Nasr City, Cairo (Egypt)

    2010-05-15

    This paper presents a design for a fault diagnosis system (FDS) for tapped HV/EHV power transmission lines. These lines have two different protection zones. The proposed approach reduces the cost and the complexity of the FDS for these types of lines. The FDS consists basically of fifteen artificial neural networks (ANNs). The FDS basic objectives are mainly: (1) the detection of the system fault; (2) the localization of the faulted zone; (3) the classification of the fault type; and finally (4) the identification of the faulted phase. This FDS is structured in a three hierarchical levels. In the first level, a preprocessing unit to the input data is performed. An ANN, in the second level, is designed in order to detect and zone localize the line faults. In the third level, two zone diagnosis systems (ZDS) are designed. Each ZDS is dedicated to one zone and consists of seven parallel-cascaded ANN's. Four-parallel ANN's are designed in order to achieve the fault type classification. While, the other three cascaded ANN's are designed mainly for the selection of the faulted phase. A smoothing unit is also configured to smooth out the output response of the proposed FDS. The proposed FDS is designed and evaluated using the local measurements of the three-phase voltage and current samples acquired at only one side. The sampling rate was taken 16 samples per cycle of the power frequency. Data window of 4 samples was utilized. These samples were generated using the EMTP simulation program, applied to the High-Dam/Cairo 500 kV tapped transmission line. All possible shunt fault types were considered. The effect of fault location and fault incipience time were also included. Moreover, the effect of load and capacitor switchings on the FDS performance was investigated. Testing results have proved the capability as well as the effectiveness of the proposed FDS. (author)

  18. Study on Tower Models for EHV Transmission Line

    Directory of Open Access Journals (Sweden)

    Xu Bao-Qing

    2016-01-01

    Full Text Available Lightning outage accident is one of the main factors that threat seriously the safe and reliable operation of power system. So it is very important to establish reasonable transmission tower model and evaluate the impulse response characteristic of lightning wave traveling on the transmission tower properly for determining reliable lightning protection performance. With the help of Electromagnetic Transient Program (EMTP, six 500kV tower models are built. Aiming at one line to one transformer operating mode of 500kV substation, the intruding wave overvoltage under different tower models is calculated. The effect of tower model on intruding overvoltage has been studied. The results show that different tower models can result in great differences to the calculation results. Hence, reasonable selection of the tower model in the calculation of back- strike intruding wave is very important.

  19. Research on Line Patrol Strategy of 110kV Transmission Line after Lightning Strike

    Directory of Open Access Journals (Sweden)

    Li Mingjun

    2016-01-01

    Full Text Available Lightning faults occupy in the majority of instantaneous fault and reclosing can usually be successful, so power supply can be restored without immediate patrol in many cases. Firstly, this paper introduces the lightning fault positioning and identifying method. Then test electrical performance of insulators after lightning strike from 110kV lines. Data shows that lightning strike has little effect on the electric performance of insulator. Finally, illustrating disposal process of the 110 kV transmission line after lightning fault, certifying that the power supply reliability be ensured without line patrol.

  20. Electron transmission through a periodically driven graphene magnetic barrier

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, R., E-mail: rbiswas.pkc@gmail.com [Department of Physics, P. K. College, Contai, Purba Medinipur, West Bengal – 721401 (India); Maiti, S. [Ajodhya Hills G.S.A.T High School, Ajodhya, Purulia, West Bengal – 723152 (India); Mukhopadhyay, S. [Purulia Zilla School, Dulmi Nadiha, Purulia, West Bengal – 723102 (India); Sinha, C. [Department of Physics, P. K. College, Contai, Purba Medinipur, West Bengal – 721401 (India); Department of Theoretical Physics, Indian Association for the Cultivation of Science, Jadavpur – 700032 (India)

    2017-05-10

    Electronic transport through graphene magnetic barriers is studied theoretically in presence of an external time harmonic scalar potential in the framework of non-perturbative Landau–Floquet Formalism. The oscillating field mostly suppresses the transmission for rectangular magnetic barrier structure and exhibits the Fano resonance for multiphoton processes due to the presence of bound state inside the barrier. While, for a pair of delta function barriers of larger separation, the oscillating potential suppresses the usual Fabry–Perot oscillations in the transmission and a new type of asymmetric Fano resonance is noted for smaller separation, occurring due to extended states between the barriers. - Highlights: • Tunnelling of the Dirac Fermions through oscillating pure magnetic barriers is reported for the first time. • The high energy transmission through a graphene magnetic barrier is suppressed by the application of time periodic modulation. • Suppression of the Fabry Perot transmission is noted due to the application of an external time harmonic potential. • Two kinds of the Fano resonances are noted in transmission through a pair of modulated δ-function magnetic barriers.

  1. High-quality MR imaging using flexible transmission line resonators

    International Nuclear Information System (INIS)

    Bader, R.; Zabel, H.J.; Lorenz, W.J.

    1986-01-01

    High-quality MR imaging of partial human body regions can be achieved by using transmission line resonators (TLRs) as surface coils. TLRs with loops of different shapes and sizes are particularly well suited for examinations of the spinal cord, the extremities, the face, and the fairly inaccessible throat. Their high filling factor and loaded Q-value of about 160 greatly improve the quality of the image, compared to images obtained with standard surface coils. The stabilizing effect of the length of the TLR makes tuning between patients unnecessary. Immediate adaptation to the body contours of an individual patient is possible

  2. Walking Posture Control of Transmission Line Single Arm Inspection Robot

    Science.gov (United States)

    Yan, Yu; Liu, Xiaqing; Li, Jinliang; Ou, Yuexiong

    2017-07-01

    To control the walking posture according to transmission line single arm inspection robot, the robot is divided into normal walking and climbing walking two state, and gives the definition, then based on the state space method of state variable feedback and PD control method is used to control the two states, two kinds of control method of simulation by using Matlab, in the end, the two control methods proposed is validated in the actual circuit structures. The results show that, the proposed control method is rapid and effective, and can meet the needs of practical application.

  3. Time-dependent sources identification for transmission lines problems

    Directory of Open Access Journals (Sweden)

    J. Benoit

    2015-10-01

    Full Text Available This paper is devoted to introduce an extension to the Linear Combination of Configuration Fields (LCCF. This new numerical method was designed to compute the time profile of an electromagnetic source radiating a specified electromagnetic field in all or part of the computational domain, for a specified duration. Here, we extend this idea within the framework of a transmission lines network. The principle of the method is first validated numerically. Then we prospect the same ideas in a real-data experiment which shows that the method is ready for real-life investigations.

  4. 76 FR 15970 - Central Ferry to Lower Monumental 500-kilovolt Transmission Line Project

    Science.gov (United States)

    2011-03-22

    ... entry of the Central Ferry-Lower Monumental transmission line into the substation. Fiber optic cable...-kilovolt Transmission Line Project AGENCY: Bonneville Power Administration (BPA), Department of Energy (DOE... availability of the ROD to implement the Central Ferry--Lower Monumental 500-kilovolt (kV) Transmission Line...

  5. Comprehensive investigation of the angular transmission in magnetic spectrometers

    CERN Document Server

    Pereira-Conca, J; Schmidt, K H

    2003-01-01

    Magnetic spectrometers are largely used in experimental nuclear physics. These devices allow one to perform precise measurements of the reaction kinematics or to separate and fully identify the reaction residues for nuclear-dynamics and structure studies. They can also be used as separators to produce radioactive nuclear beams. However, all these applications are affected by the limited transmission of the reaction residues through the spectrometer. The final transmission depends on the ion-optical characteristics and the mechanical constraints of the spectrometer but also on the kinematic properties of the considered nuclei. The ion optics are characterised by the bending and focusing powers of the magnetic elements which constitute the spectrometer. The reaction mechanism determines the kinematics of the particles. The transmission losses in any magnetic spectrometer can be attributed to its limited acceptance in longitudinal momentum and angle. The limitation in longitudinal momentum can be overcome by com...

  6. Advanced transmission electron microscopy on nanostructured magnetic materials

    OpenAIRE

    Campanini, Marco

    2015-01-01

    This doctoral work is focused on the study of nanostructured magnetic materials by advanced transmission electron microscopy (TEM) techniques, with emphasis on Ni2MnGa shape memory alloy thin films and magnetite nanoparticles for biomedical applications. The combination of high-resolution transmission electron microscopy and electron diffraction to characterize morphology and crystalline structure, with Lorentz microscopy and Electron Holography, permits to achieve a deep insight in the s...

  7. Transmission-line-circuit model of an 85-TW, 25-MA pulsed-power accelerator

    Science.gov (United States)

    Hutsel, B. T.; Corcoran, P. A.; Cuneo, M. E.; Gomez, M. R.; Hess, M. H.; Hinshelwood, D. D.; Jennings, C. A.; Laity, G. R.; Lamppa, D. C.; McBride, R. D.; Moore, J. K.; Myers, A.; Rose, D. V.; Slutz, S. A.; Stygar, W. A.; Waisman, E. M.; Welch, D. R.; Whitney, B. A.

    2018-03-01

    We have developed a physics-based transmission-line-circuit model of the Z pulsed-power accelerator. The 33-m-diameter Z machine generates a peak electrical power as high as 85 TW, and delivers as much as 25 MA to a physics load. The circuit model is used to design and analyze experiments conducted on Z. The model consists of 36 networks of transmission-line-circuit elements and resistors that represent each of Zs 36 modules. The model of each module includes a Marx generator, intermediate-energy-storage capacitor, laser-triggered gas switch, pulse-forming line, self-break water switches, and tri-plate transmission lines. The circuit model also includes elements that represent Zs water convolute, vacuum insulator stack, four parallel outer magnetically insulated vacuum transmission lines (MITLs), double-post-hole vacuum convolute, inner vacuum MITL, and physics load. Within the vacuum-transmission-line system the model conducts analytic calculations of current loss. To calculate the loss, the model simulates the following processes: (i) electron emission from MITL cathode surfaces wherever an electric-field threshold has been exceeded; (ii) electron loss in the MITLs before magnetic insulation has been established; (iii) flow of electrons emitted by the outer-MITL cathodes after insulation has been established; (iv) closure of MITL anode-cathode (AK) gaps due to expansion of cathode plasma; (v) energy loss to MITL conductors operated at high lineal current densities; (vi) heating of MITL-anode surfaces due to conduction current and deposition of electron kinetic energy; (vii) negative-space-charge-enhanced ion emission from MITL anode surfaces wherever an anode-surface-temperature threshold has been exceeded; and (viii) closure of MITL AK gaps due to expansion of anode plasma. The circuit model is expected to be most accurate when the fractional current loss is small. We have performed circuit simulations of 52 Z experiments conducted with a variety of accelerator

  8. Doppler-shifted neutral beam line shape and beam transmission

    Energy Technology Data Exchange (ETDEWEB)

    Kamperschroer, J.H.; Grisham, L.R.; Kokatnur, N.; Lagin, L.J.; Newman, R.A.; O`Connor, T.E.; Stevenson, T.N.; von Halle, A.

    1994-04-01

    Analysis of Doppler-shifted Balmer-{alpha} line emission from the TFTR neutral beam injection systems has revealed that the line shape is well approximated by the sum of two Gaussians, or, alternatively, by a Lorentzian. For the sum of two Gaussians, the broad portion of the distribution contains 40% of the beam power and has a divergence five times that of the narrow part. Assuming a narrow 1/e- divergence of 1.3{degrees} (based on fits to the beam shape on the calorimeter), the broad part has a divergence of 6.9{degrees}. The entire line shape is also well approximated by a Lorentzian with a half-maximum divergence of 0.9{degrees}. Up to now, fusion neutral beam modelers have assumed a single Gaussian velocity distribution, at the extraction plane, in each direction perpendicular to beam propagation. This predicts a beam transmission efficiency from the ion source to the calorimeter of 97%. Waterflow calorimetry data, however, yield a transmission efficiency of {approximately}75%, a value in rough agreement with predictions of the Gaussian or Lorentzian models presented here. The broad wing of the two Gaussian distribution also accurately predicts the loss in the neutralizer. An average angle of incidence for beam loss at the exit of the neutralizer is 2.2{degrees}, rather than the 4.95{degrees} subtended by the center of the ion source. This average angle of incidence, which is used in computing power densities on collimators, is shown to be a function of beam divergence.

  9. Doppler-shifted neutral beam line shape and beam transmission

    International Nuclear Information System (INIS)

    Kamperschroer, J.H.; Grisham, L.R.; Kokatnur, N.; Lagin, L.J.; Newman, R.A.; O'Connor, T.E.; Stevenson, T.N.; von Halle, A.

    1994-04-01

    Analysis of Doppler-shifted Balmer-α line emission from the TFTR neutral beam injection systems has revealed that the line shape is well approximated by the sum of two Gaussians, or, alternatively, by a Lorentzian. For the sum of two Gaussians, the broad portion of the distribution contains 40% of the beam power and has a divergence five times that of the narrow part. Assuming a narrow 1/e- divergence of 1.3 degrees (based on fits to the beam shape on the calorimeter), the broad part has a divergence of 6.9 degrees. The entire line shape is also well approximated by a Lorentzian with a half-maximum divergence of 0.9 degrees. Up to now, fusion neutral beam modelers have assumed a single Gaussian velocity distribution, at the extraction plane, in each direction perpendicular to beam propagation. This predicts a beam transmission efficiency from the ion source to the calorimeter of 97%. Waterflow calorimetry data, however, yield a transmission efficiency of ∼75%, a value in rough agreement with predictions of the Gaussian or Lorentzian models presented here. The broad wing of the two Gaussian distribution also accurately predicts the loss in the neutralizer. An average angle of incidence for beam loss at the exit of the neutralizer is 2.2 degrees, rather than the 4.95 degrees subtended by the center of the ion source. This average angle of incidence, which is used in computing power densities on collimators, is shown to be a function of beam divergence

  10. On setting magnets in the PEP beam-transport line

    International Nuclear Information System (INIS)

    Peterson, J.M.

    1979-01-01

    This paper discusses magnets in the PEP beam-transport line. Topics discussed are: conditioning, direction of excitation, rate of excitation; determination of the excitation current for the principal bend magnets; steering mechanisms; bump magnets; and determination of excitation currents of the quadrupole magnets

  11. Wild Horse 69-kV transmission line environmental assessment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    Hill County Electric Cooperative Inc. (Hill County) proposes to construct and operate a 69-kV transmission line from its North Gildford Substation in Montana north to the Canadian border. A vicinity project area map is enclosed as a figure. TransCanada Power Corporation (TCP), a Canadian power-marketing company, will own and construct the connecting 69-kV line from the international border to Express Pipeline`s pump station at Wild Horse, Alberta. This Environmental Assessment is prepared for the Department of Energy (DOE) as lead federal agency to comply with the requirements of the National Environmental Policy Act (NEPA), as part of DOE`s review and approval process of the applications filed by Hill County for a DOE Presidential Permit and License to Export Electricity to a foreign country. The purpose of the proposed line is to supply electric energy to a crude oil pump station in Canada, owned by Express Pipeline Ltd. (Express). The pipeline would transport Canadian-produced oil from Hardisty, Alberta, Canada, to Caster, Wyoming. The Express Pipeline is scheduled to be constructed in 1996--97 and will supply crude oil to refineries in Wyoming and the midwest.

  12. Wild Horse 69-kV transmission line environmental assessment

    International Nuclear Information System (INIS)

    1996-12-01

    Hill County Electric Cooperative Inc. (Hill County) proposes to construct and operate a 69-kV transmission line from its North Gildford Substation in Montana north to the Canadian border. A vicinity project area map is enclosed as a figure. TransCanada Power Corporation (TCP), a Canadian power-marketing company, will own and construct the connecting 69-kV line from the international border to Express Pipeline's pump station at Wild Horse, Alberta. This Environmental Assessment is prepared for the Department of Energy (DOE) as lead federal agency to comply with the requirements of the National Environmental Policy Act (NEPA), as part of DOE's review and approval process of the applications filed by Hill County for a DOE Presidential Permit and License to Export Electricity to a foreign country. The purpose of the proposed line is to supply electric energy to a crude oil pump station in Canada, owned by Express Pipeline Ltd. (Express). The pipeline would transport Canadian-produced oil from Hardisty, Alberta, Canada, to Caster, Wyoming. The Express Pipeline is scheduled to be constructed in 1996--97 and will supply crude oil to refineries in Wyoming and the midwest

  13. Proposal of the Measurement Method of the Transmission Line Constants by Automatic Oscillograph Utilization

    Science.gov (United States)

    Ooura, Yoshifumi

    The author devised new method for measurement of the transmission line constants of high precision with the automatic oscillograph. This paper is proposal of new method for measurement of the transmission line constants. The author utilized that the inherent eigenvector matrixs of transmission line had an equal relation with four-terminal constants eigenvector matrixs of transmission line. And the author calculated four-terminal constants of transmission line from the data (voltage-current data of the automatic oscillograph) of six cases of transmission line system faults and devised the method for measurement for transmission line constants from analysis of the four-terminal constants of transmission line next. Furthermore, the author inspected this new method in the system fault simulations of the EMTP transmission line system model. It was shown that the result is the measurement method of high accuracy. From now on, the author advances the measurement of the transmission line constants from actual system faults data of the transmission line and its periphery with the cooperation power system companies.

  14. Mechanical Calculation of Power Lines and Strands in Overhead Transmission Lines

    Directory of Open Access Journals (Sweden)

    Li Yongping

    2016-01-01

    Full Text Available This paper discusses the issue of shape and stress of overhead transmission lines. It fully considers that the conductor is subjected to axial force, shear, bending moment simultaneousiy. And the flat wire is basically in the elastic range. Because the stress is the strength of a certain point, the bending rigidity of the overhead lines can not be ignored. However, the catenary has been used in previous research and the force of the overhead lines is obtained on this basis. The author establishes a model of wire calculation under real condition, and gives a feasible simplified model. And then it gives the line shape formula, internal force formula, formula of stress in the strands. The results show that the original stress is significantly smaller.In this paper, the stress formula is almost close to the reality. It proves the reliability of the simplified model that the line shape includes the original flexible part.The results can not only fill the gaps in the theoretical study of the overhead lines, but also have some guidance to the production and design of overhead lines.

  15. Transmission line corona losses under hoar frost conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lahti, K.; Nousiainen, K. [Tampere Univ. of Technology (Finland). Power Engineering Group; Lahtinen, M.

    1997-04-01

    Transmission line corona losses under hoar frost conditions were studied in the climate room of the high voltage laboratory of Tampere University of Technology. The measurements were performed using a coaxial measurement arrangement with different bundle and conductor types. The effects of conductor and bundle type, temperature, applied voltage and hoar frost thickness on corona losses were investigated. A two-conductor bundle had corona losses about 2.5--5 times higher than a three-conductor bundle. Relatively thin hoar frosts were used in the tests. Even the thinnest hoar frost resulted in remarkable corona losses and the losses were very sensitive to changes in the hoar frost thickness. The ambient temperature had a strong influence on the measured losses.

  16. High current nonlinear transmission line based electron beam driver

    Directory of Open Access Journals (Sweden)

    B. W. Hoff

    2017-10-01

    Full Text Available A gigawatt-class nonlinear transmission line based electron beam driver is experimentally demonstrated. Four experimental series, each with a different Marx bank charge voltage (15, 20, 25, and 30 kV, were completed. Within each experimental series, shots at peak frequencies ranging from 950 MHz to 1.45 GHz were performed. Peak amplitude modulations of the NLTL output voltage signal were found to range between 18% and 35% for the lowest frequency shots and between 5% and 20% for the highest frequency shots (higher modulation at higher Marx charge voltage. Peak amplitude modulations of the electron beam current were found to range between 10% and 20% for the lowest frequency shots and between 2% and 7% for the highest frequency shots (higher modulation at higher Marx charge voltage.

  17. Wavelet transform based digital protection for transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Valsan, Simi P.; Swarup, K.S. [Dept. of Electrical Engineering, Indian Institute of Technology Madras, Tamil Nadu (India)

    2009-09-15

    This paper presents a high speed, computationally efficient scheme for protection of transmission lines. The relay logic consists of three parts: directional protection, fault classification and fault location. Wavelet transform is used for extracting information from the fault transients and only the first level high frequency details of the voltages and currents are used. Proposed protection logic compares the directional signals from both terminals to discriminate between faults inside and outside the zone of interest. Fault classification is achieved using local terminal current information. An estimate of the location of the faults is obtained utilizing single faulted phase current information from both terminals. The logic is deterministic and can work reliably in the presence of fault resistance, load variation and CT saturation. The validity of the proposed logic was exhaustively tested by simulating various types of faults on a four bus meshed system modeled in EMTP/ATP. (author)

  18. A modular restoration tower for electric power line transmission

    Energy Technology Data Exchange (ETDEWEB)

    Nicolazzi, L.C.; Pereira, J.C.; Leonel, C.E.L.; Rocha, G.B.; Bianchezzi, V.; Mendes, F. [Universidade Federal Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica], Emails: lauro@grante.ufsc.br, jcarlos@grante.ufsc.br; Luz, R.L. [ELETROSUL Centrais Eletricas S.A., Florianopolis, SC (Brazil)], Email: rluz@eletrosul.gov.br

    2009-07-01

    The main target of this R and D project is to develop an restoration tower for electric energy lines transmission. Whereas these towers should present the main features like transport facility, easiest assembling associated with a low cost of manufacture, it was applied the single-column tower concepts supported by stays, modularized, framed and articulated at the base. The concepts used for this development was a design methodology. From the different definition situations of load, numerical models have been developed focusing the design to the best of structural element arrangements of its modules. Then, tests were performed in laboratory to determine the module structural performance for different work load situations. These tests served to identify inconsistencies in the numerical models and proposed adjustments in its design to improve its performance on the strength and stability. (author)

  19. High current nonlinear transmission line based electron beam driver

    Science.gov (United States)

    Hoff, B. W.; French, D. M.; Simon, D. S.; Lepell, P. D.; Montoya, T.; Heidger, S. L.

    2017-10-01

    A gigawatt-class nonlinear transmission line based electron beam driver is experimentally demonstrated. Four experimental series, each with a different Marx bank charge voltage (15, 20, 25, and 30 kV), were completed. Within each experimental series, shots at peak frequencies ranging from 950 MHz to 1.45 GHz were performed. Peak amplitude modulations of the NLTL output voltage signal were found to range between 18% and 35% for the lowest frequency shots and between 5% and 20% for the highest frequency shots (higher modulation at higher Marx charge voltage). Peak amplitude modulations of the electron beam current were found to range between 10% and 20% for the lowest frequency shots and between 2% and 7% for the highest frequency shots (higher modulation at higher Marx charge voltage).

  20. New circuit theory of multiconductor transmission lines resulting from a new practice of noise reduction

    Science.gov (United States)

    TOKI, Hiroshi; SATO, Kenji

    2014-01-01

    In modern life, we are surrounded by and filled with electromagnetic noise caused by the dominant use of energy in the form of electricity. This situation is brought about by the fact that the noise is not understood theoretically. A new practice of noise reduction was introduced for the construction of Heavy Ion Medical Accelerator in Chiba (HIMAC). The key concept is a symmetric three-line circuit that arranges power supplies, noise filters and magnets around a third central ground line. A continuous theoretical effort forced us to find a new circuit theory involving a multiconductor transmission-line system starting from Maxwell’s equations without any approximation. We discuss the essence of all of these experimental and theoretical developments with the hope to remove unnecessary electromagnetic noise not only from power supplies, but also from all electric devices. The newly derived circuit theory of multiconductor transmission lines is universal, and establishes the validity of the practice of noise reduction. PMID:24522153

  1. Evaluation of Fibre Lifetime in Optical Ground Wire Transmission Lines

    Science.gov (United States)

    Grunvalds, R.; Ciekurs, A.; Porins, J.; Supe, A.

    2017-06-01

    In the research, measurements of polarisation mode dispersion of two OPGWs (optical ground wire transmission lines), in total four fibres, have been carried out, and the expected lifetime of the infrastructure has been assessed on the basis of these measurements. The cables under consideration were installed in 1995 and 2011, respectively. Measurements have shown that polarisation mode dispersion values for cable installed in 1995 are four times higher than that for cable installed in 2011, which could mainly be explained by technological differences in fibre production and lower fibre polarisation mode dispersion requirements in 1995 due to lack of high-speed (over 10 Gbit/s) optical transmission systems. The calculation methodology of non-refusal work and refusal probabilities, using the measured polarisation mode dispersion parameters, is proposed in the paper. Based on reliability calculations, the expected lifetime is then predicted, showing that all measured fibres most likely will be operational within minimum theoretical service life of 25 years accepted by the industry.

  2. Research on cost control and management in high voltage transmission line construction

    Science.gov (United States)

    Xu, Xiaobin

    2017-05-01

    Enterprises. The cost control is of vital importance to the construction enterprises. It is the key to the profitability of the transmission line project, which is related to the survival and development of the electric power construction enterprises. Due to the long construction line, complex and changeable construction terrain as well as large construction costs of transmission line, it is difficult for us to take accurate and effective cost control on the project implementation of entire transmission line. Therefore, the cost control of transmission line project is a complicated and arduous task. It is of great theoretical and practical significance to study the cost control scheme of transmission line project by a more scientific and efficient way. Based on the characteristics of the construction project of the transmission line project, this paper analyzes the construction cost structure of the transmission line project and the current cost control problem of the transmission line project, and demonstrates the necessity and feasibility of studying the cost control scheme of the transmission line project more accurately. In this way, the dynamic cycle cost control process including plan, implementation, feedback, correction, modification and re-implement is achieved to realize the accurate and effective cost control of entire electric power transmission line project.

  3. Potential and electric field profiles for transmission line insulators

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, S.B.; Kumar, U. [Indian Inst. of Science, Bangalore (India). Dept. of Electrical Engineering, High Voltage Laboratory

    2008-07-01

    Overhead transmission lines are used to transmit bulk power at high voltages over very long distances. The objective of this study was to deduce accurate quantitative data on electrical stress distribution on 6 commonly used porcelain insulator strings. Both single disc and 15 disc strings corresponding to 220 kV line were considered. Both volume and surface electrical stresses along the porcelain-to-air and cement-to-air interfaces were deduced. The prevailing stress during laboratory pollution tests was also evaluated. A quantitative comparison of the stresses across commonly used insulators was also carried out. A numerical approach was used since the use of analytical methods for the required field solution was impractical because the geometry does not fit into any of the orthogonal curvilinear coordinates. In this study, the governing field was electrostatic under clean conditions and steady conduction under polluted conditions. Therefore the governing field equation was Laplacian, with complex permittivity for combined fields. 12 refs., 2 tabs., 13 figs.

  4. Backflashover simulation of HV transmission lines with enhanced counterpoise groundings

    Energy Technology Data Exchange (ETDEWEB)

    Gatta, F.M.; Geri, A.; Lauria, S.; Maccioni, M. [Department of Electrical Engineering, University of Rome ' ' La Sapienza' ' , Via Eudossiana no. 18, 00184 Roma (Italy)

    2009-07-15

    This paper deals with the backflashover phenomenon in HV overhead transmission lines (TLs) with towers grounded by means of long counterpoises, typically used in high resistivity soils. Although long counterpoises are effective in reducing the grounding impedance at power frequency, their impulse response may affect negatively the TL backflashover rate. The study is focused on the enhancement of TL lightning performance obtainable by adding a small number of vertical grounding rods to horizontal counterpoises. An extensive ATP-EMTP parametric analysis, based on a detailed 161 kV TL model including the leader progression model (LPM) of line insulations and the non-linear transient behaviour of grounding systems, has been carried out taking into account several different values of soil resistivity as well as varying numbers, locations and lengths of additional vertical rods. Critical lightning current ranges causing backflashover have been then predicted for several lightning waveforms, of different severity. The paper shows that the addition of a few vertical grounding rods significantly improves TL lightning performance by increasing critical lightning current values, even if their influence is negligible at power frequency. The authors have ascertained an increment of average critical backflashover current up to {proportional_to}55% for some typical TL grounding system configurations and lightning waveshapes. (author)

  5. Overhead Transmission Lines Deicing under Different Incentive Displacement

    Directory of Open Access Journals (Sweden)

    Qing He

    2014-01-01

    Full Text Available Overhead transmission line icing is one of the main factors affecting safety and reliability of power grid. This paper proposed an excitation deicing method of iced wire and theoretically revealed the ice removal mechanism under displacement excitation conditions, by taking the LGJ-70/10 glaze icing wire as the 3D model and analyzing and studying its dynamic response under the effect of displacement excitation. The simulation results show that the stress of wire icing area is enlarged with the increase of excitation displacement and frequency. Through the comparison of the compression strength experimental results on a series of different iced wires in low temperature environment, the authors found out that the stress generated from the wire icing area is greater than the crushing strength of the ice within the scope of the calculation parameters, which proved the validity and the feasibility of the method, and finally the suitable excitation displacement is determined. Following studies show that, as far as possible, it is necessary to reduce the incentive displacement and also to select the appropriate constraint length in order to avoid the line jumping that may be caused by large span ice shedding.

  6. Polar On-Line Acquisition Relay and Transmission System (POLARATS)

    Energy Technology Data Exchange (ETDEWEB)

    Yuracko, K.

    2004-07-15

    POLARATS (Polar On-Line Acquisition Relay And Transmission System) is being developed by YAHSGS LLC (YAHSGS) and Oak Ridge National Laboratory (ORNL) to provide remote, unattended monitoring of environmental parameters under harsh environmental conditions. In particular, instrumental design and engineering is oriented towards protection of human health in the Arctic, and with the additional goal of advancing Arctic education and research. POLARATS will obtain and transmit environmental data from hardened monitoring devices deployed in locations important to understanding atmospheric and aquatic pollutant migration as it is biomagnified in Arctic food chains. An Internet- and personal computer (PC)-based educational module will provide real time sensor data, on-line educational content, and will be integrated with workbooks and textbooks for use in middle and high school science programs. The educational elements of POLARATS include an Internet-based educational module that will instruct students in the use of the data and how those data fit into changing Arctic environments and food chains. POLARATS will: (1) Enable students, members of the community, and scientific researchers to monitor local environmental conditions in real time over the Internet; and (2) Provide additional educational benefits through integration with middle- and high-school science curricula. Information will be relayed from POLARATS devices to classrooms and libraries along with custom-designed POLARATS teaching materials that will be integrated into existing curricula to enhance the educational benefits realized from the information obtained.

  7. Methods and results of modeling and transmission-line calculations of the superconducting dipole chains of CERN's LHC collider

    CERN Document Server

    Bourgeois, F

    2001-01-01

    Electrical modeling and simulation of the LHC magnet strings are being used to determine the key parameters that are needed for the design of the powering and energy extraction equipment. Poles and zeros of the Laplace expression approximating the Bode plot of the measured coil impedance are used to synthesize an R/L/C model of the magnet. Subsequently, this model is used to simulate the behavior of the LHC main dipole magnet string. Lumped transmission line behavior, impedance, resonance, propagation of the power supply ripple, ramping errors, energy extraction transients and their damping are presented in this paper. (3 refs).

  8. Compact Two-Section Half-Wave Balun Based on Planar Artificial Transmission Lines

    Directory of Open Access Journals (Sweden)

    Changjun Liu

    2015-01-01

    Full Text Available Artificial transmission lines are realized by a series of meandered-line inductors, parallel-plate capacitors, and interdigital capacitors, which belong to metamaterial transmission lines. An ameliorated artificial transmission line is proposed to realize a low characteristic impedance transmission line. A two-section half-wave balun at 900 MHz is designed, fabricated, and measured in this paper. The compact balun is based on conventional and ameliorated planar artificial transmission lines instead of microstrip transmission lines. The main advantage of the proposed balun is its size reduction, which occupies only about 10% of a conventional one. Measured results match well with theory and simulation. The balun features excellent amplitude and phase balance in microwave power combining and a reasonable bandwidth of the return loss as well.

  9. Structural health monitoring of compression connectors for overhead transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hong [ORNL; Wang, Jy-An John [ORNL; Swindeman, Joseph P [ORNL; Ren, Fei [ORNL; Chan, John [Electric Power Research Institute (EPRI)

    2017-01-01

    Two-stage aluminum conductor steel-reinforced (ACSR) compression connectors are extensively used in US overhead transmission lines. The connectors are made by crimping a steel sleeve onto a steel core and an aluminum sleeve over aluminum conductive strands. The connectors are designed to operate at temperatures up to 125 C, but their performance is increasingly degrading because of overloading of lines. Currently, electric utilities conduct routine line inspections using thermal and electrical measurements. However, information about the structural integrity of connectors cannot be obtained. In this work, structural health monitoring (SHM) of compression connectors was studied using electromechanical impedance (EMI) analysis. Lead zirconate titanate (PZT)-5A was identified as a smart material for SHM. A flexible high-temperature bonding layer was used to address challenges in PZT integration due to a significant difference in the coefficients of thermal expansion of PZT and the aluminum substrate. The steel joint on the steel core was investigated because it is responsible for the ultimate tensile strength of the connector. Tensile testing was used to create structural damage to the joint, or steel core pullout, and thermal cycling introduced additional structural perturbations. EMI measurements were conducted between the tests. The root mean square deviation (RMSD) of EMI was identified as a damage index. The use of steel joints has been shown to enable SHM under simulated conditions. The EMI signature is sensitive to variations in structural conditions. RMSD can be correlated to the structural health of a connector and has potential for use in the SHM and structural integrity evaluation.

  10. Reduction of the visual impact of overhead transmission line systems through utilisation of line surge arresters as lightning protection

    DEFF Research Database (Denmark)

    Sørensen, Thomas Kjærsgaard; Holbøll, Joachim

    2008-01-01

    in line performance and lightning protection of the nearest substations requires thorough modelling of the new line including all electrical parameters necessary for performance evaluation under all conditions. In this paper, explicit use of line surge arresters as lightning protection on the line...... of the line and the required protection level in substations. The use of line surge arresters gives the possibility to decrease the height of towers thereby improving the visual impression of the overhead line transmission systems. However the usage of line surge arresters will, dependent upon line surge...

  11. Transmission line equivalent circuit model applied to a plasmonic grating nanosurface for light trapping.

    Science.gov (United States)

    Polemi, Alessia; Shuford, Kevin L

    2012-01-02

    In this paper, we show how light absorption in a plasmonic grating nanosurface can be calculated by means of a simple, analytical model based on a transmission line equivalent circuit. The nanosurface is a one-dimensional grating etched into a silver metal film covered by a silicon slab. The transmission line model is specified for both transverse electric and transverse magnetic polarizations of the incident light, and it incorporates the effect of the plasmonic modes diffracted by the ridges of the grating. Under the assumption that the adjacent ridges are weakly interacting in terms of diffracted waves, we show that the approximate, closed form expression for the reflection coefficient at the air-silicon interface can be used to evaluate light absorption of the solar cell. The weak-coupling assumption is valid if the grating structure is not closely packed and the excitation direction is close to normal incidence. Also, we show the utility of the circuit theory for understanding how the peaks in the absorption coefficient are related to the resonances of the equivalent transmission model and how this can help in designing more efficient structures.

  12. In situ transmission electron microscopy for magnetic nanostructures

    DEFF Research Database (Denmark)

    Ngo, Duc-The; Kuhn, Luise Theil

    2016-01-01

    Nanomagnetism is a subject of great interest because of both application and fundamental aspects in which understanding of the physical and electromagnetic structure of magnetic nanostructures is essential to explore the magnetic properties. Transmission electron microscopy (TEM) is a powerful tool...... that allows understanding of both physical structure and micromagnetic structure of the thin samples at nanoscale. Among TEM techniques, in situ TEM is the state-of-the-art approach for imaging such structures in dynamic experiments, reconstructing a real-time nanoscale picture of the properties......-structure correlation. This paper aims at reviewing and discussing in situ TEM magnetic imaging studies, including Lorentz microscopy and electron holography in TEM, applied to the research of magnetic nanostructures....

  13. Multipactor Mitigation in Coaxial Lines by Means of Permanent Magnets

    CERN Document Server

    Gonzalez-Iglesias, D; Anza, S; Vague, J; Gimeno, B; Boria, V E; Raboso, D; Vicente, C; Gil, J; Caspers, F; Conde, L

    2014-01-01

    The main aim of this paper is the analysis of the feasibility of employing permanent magnets for the multipactor mitigation in a coaxial waveguide. First, the study of a coaxial line immersed in a uniform axial magnetic field shows that multipactor can be suppressed at any RF frequency if the external magnetic field is strong enough. Both theoretical simulations and experimental tests validate this statement. Next, multipactor breakdown of a coaxial line immersed in a hollow cylindrical permanent magnet is analyzed. Numerical simulations show that multipactor can be suppressed in a certain RF frequency range. The performed experimental test campaign demonstrates the capability of the magnet to avoid the multipactor electron multiplication process.

  14. A surface acoustic wave electric field strength meter for environmental studies of HV transmission lines

    International Nuclear Information System (INIS)

    Grandolfo, M.; Ranghiasci, C.; Verona, E.

    1988-01-01

    In recent years, there has been a significant increase in concern over the health and safety aspects of high voltage transmission lines (HVTL). The majority of research has focused on effects directly or indirectly involved with the central nervous system, including physiological, ultrastructural, and biochemical alterations, changes in blood composition, behaviour, reproduction, and development. Several recent epidemiological reports have presented preliminary data suggesting an increase in the incidence of cancer among children and adults exposed to magnetic fields through living close to various types of electrical power lines or devices. With the increase in environmental concerns there has been a concomitant consideration of biological effects and health implications related to presently existing HVTL and those planned in the future. It was concluded that the electric and magnetic field strengths and the electrical discharges are the most important electrophysical factors. Thus, it has been deemed necessary to develop measuring means to determine the field strengths in areas surrounding electric installations, in particular at ground level. In the present paper an electric field meter, based on the use of a surface acoustic wave (SAW) delay line, is presented and the experimental results obtained are discussed

  15. Iterative reconstruction of magnetic induction using Lorentz transmission electron tomography

    International Nuclear Information System (INIS)

    Phatak, C.; Gürsoy, D.

    2015-01-01

    Intense ongoing research on complex nanomagnetic structures requires a fundamental understanding of the 3D magnetization and the stray fields around the nano-objects. 3D visualization of such fields offers the best way to achieve this. Lorentz transmission electron microscopy provides a suitable combination of high resolution and ability to quantitatively visualize the magnetization vectors using phase retrieval methods. In this paper, we present a formalism to represent the magnetic phase shift of electrons as a Radon transform of the magnetic induction of the sample. Using this formalism, we then present the application of common tomographic methods particularly the iterative methods, to reconstruct the 3D components of the vector field. We present an analysis of the effect of missing wedge and the limited angular sampling as well as reconstruction of complex 3D magnetization in a nanowire using simulations. - Highlights: • We present a formalism to represent electron-optical magnetic phase shift as a Radon transform of the 3D magnetic induction of the nano-object. • We have analyzed four different tomographic reconstruction methods for vectorial data reconstruction. • Reconstruction methods were tested for varying experimental limitations such as limited tilt range and limited angular sampling. • The analysis showed that Gridrec and SIRT methods performed better with lower errors than other reconstruction methods

  16. Seasonal Patterns of Melatonin, Cortisol, and Progesterone Secretion in Female Lambs Raised Beneath a 500-KV Transmission Line

    Science.gov (United States)

    Lee, Jack Monroe, Jr.

    There is ongoing controversy about the possibility of adverse biological effects from environmental exposures to electric and magnetic fields. These fields are produced by all electrical equipment and appliances including electrical transmission lines. The objective of this environmental science study was to investigate the possible effects of a high voltage transmission line on domestic sheep (Ovis aries L.), a species that can often be found near such lines. The study was primarily designed to determine whether a specific effect of electric and magnetic fields found in laboratory animals also occurs in livestock under natural environmental conditions. The effect is the ability of fields, at levels found in the environment, to significantly depress the normally high nocturnal concentrations of the pineal hormone-melatonin. Ten female Suffolk lambs were penned for 10 months directly beneath a 500-kV transmission line near Estacada, Oregon. Ten other lambs of the same type were penned in a control area away from the transmission line where electric and magnetic fields were at ambient levels. Serum melatonin was analyzed by radioimmunoassay (RIA) from 6618 blood samples collected at 0.5 to 3-hour intervals over eight 48-hour periods. Serum progesterone was analyzed by RIA from blood samples collected twice weekly. Serum cortisol was also assayed by RIA from the blood samples collected during the 48-hour samples. Results showed that lambs in both the control and line groups had the typical pattern of melatonin secretion consisting of low daytime and high nighttime serum concentrations. There were no statistically significant differences between groups in melatonin levels, or in the phase or duration of the nighttime melatonin elevation. Age at puberty and number of reproductive cycles also did not differ between groups. Serum cortisol showed a circadian rhythm with highest concentrations during the day. There were, however, no differences in cortisol concentrations

  17. The Evaluation Method of the Lightning Strike on Transmission Lines Aiming at Power Grid Reliability

    Science.gov (United States)

    Wen, Jianfeng; Wu, Jianwei; Huang, Liandong; Geng, Yinan; Yu, zhanqing

    2018-01-01

    Lightning protection of power system focuses on reducing the flashover rate, only distinguishing by the voltage level, without considering the functional differences between the transmission lines, and being lack of analysis the effect on the reliability of power grid. This will lead lightning protection design of general transmission lines is surplus but insufficient for key lines. In order to solve this problem, the analysis method of lightning striking on transmission lines for power grid reliability is given. Full wave process theory is used to analyze the lightning back striking; the leader propagation model is used to describe the process of shielding failure of transmission lines. The index of power grid reliability is introduced and the effect of transmission line fault on the reliability of power system is discussed in detail.

  18. Electric Utility Transmission and Distribution Line Engineering Program

    Energy Technology Data Exchange (ETDEWEB)

    Peter McKenny

    2010-08-31

    Economic development in the United States depends on a reliable and affordable power supply. The nation will need well educated engineers to design a modern, safe, secure, and reliable power grid for our future needs. An anticipated shortage of qualified engineers has caused considerable concern in many professional circles, and various steps are being taken nationwide to alleviate the potential shortage and ensure the North American power system's reliability, and our world-wide economic competitiveness. To help provide a well-educated and trained workforce which can sustain and modernize the nation's power grid, Gonzaga University's School of Engineering and Applied Science has established a five-course (15-credit hour) Certificate Program in Transmission and Distribution (T&D) Engineering. The program has been specifically designed to provide working utility engineering professionals with on-line access to advanced engineering courses which cover modern design practice with an industry-focused theoretical foundation. A total of twelve courses have been developed to-date and students may select any five in their area of interest for the T&D Certificate. As each course is developed and taught by a team of experienced engineers (from public and private utilities, consultants, and industry suppliers), students are provided a unique opportunity to interact directly with different industry experts over the eight weeks of each course. Course material incorporates advanced aspects of civil, electrical, and mechanical engineering disciplines that apply to power system design and are appropriate for graduate engineers. As such, target students for the certificate program include: (1) recent graduates with a Bachelor of Science Degree in an engineering field (civil, mechanical, electrical, etc.); (2) senior engineers moving from other fields to the utility industry (i.e. paper industry to utility engineering or project management positions); and (3) regular

  19. Seasonal Patterns of Melatonin, Cortisol, and Progesterone Secretion in Female Lambs Raised Beneath a 500-kV Transmission Line.

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jack M.

    1992-06-01

    Although several kinds of biological effects of electric and magnetic fields have been reported from laboratory studies, few have been independently replicated. When this study was being planned, the suppression of nighttime melatonin in rodents was thought to represent one of the strongest known effects of these fields. The effect had been replicated by a single laboratory for 60-Hz electric fields, and by multiple laboratories for d-c magnetic fields. The primary objective of this study was to determine whether the effect of electric and magnetic fields on melatonin would also occur in sheep exposed to a high voltage transmission line. The specific hypothesis tested by this experiment was as follows: The electrical environment produced by a 60-Hz, 500-kV transmission line causes a depression in nocturnal melatonin in chronically exposed female lambs. This may mimic effects of pinealectomy or constant long-day photoperiods, thus delaying the onset of reproductive cycles. Results of the study do not provide evidence to support the hypothesis. Melatonin concentrations in the sheep exposed to the transmission line showed the normal pattern of low daytime and high nighttime serum levels. As compared to the control group, there were no statistically significant group differences in the mean amplitude, phase, or duration of the nighttime melatonin elevation.

  20. Extragalactic circuits, transmission lines, and CR particle acceleration

    Directory of Open Access Journals (Sweden)

    Kronberg Philipp P.

    2015-01-01

    Full Text Available A non-negligible fraction of a Supermassive Black Hole's (SMBH rest mass energy gets transported into extragalactic space by a remarkable process in jets which are incompletely understood. What are the physical processes which transport this energy? It is likely that the energy flows electromagnetically, rather than via a particle beam flux. The deduced electromagnetic fields may produce particles of energy as high as ∼ 1020 eV. The energetics of SMBH accretion disk models and the electromagnetic energy transfer imply that a SMBH should generate a 1018 − 1019 Ampères current close to the black hole and its accretion disk. We describe the so far best observation-based estimate of the magnitude of the current flow along the axis of the jet extending from the nucleus of the active galaxy in 3C303. The current is measured to be I ∼ 1018 Ampères at ∼ 40 kpc away from the AGN. This indicates that organised current flow remains intact over multi-kpc distances. The electric current I transports electromagnetic power into free space, P = I2Z, where Z ∼ 30 Ohms is related to the impedance of free space, and this points to the existence of cosmic electric circuit. The associated electric potential drop, V = IZ, is of the order of that required to generate Ultra High Energy Cosmic Rays (UHECR. We also explore further implications, including disruption/deflection of the power flow and also why such measurements, exemplified by those on 3C303, are currently very difficult to make and to unambiguously interpret. This naturally leads to the topic of how such measurements can be extended and improved in the future. We describe the analogy of electromagnetically dominated jets with transmission lines. High powered jets in vacuo can be understood by approximate analogy with a waveguide. The importance of inductance, impedance, and other laboratory electrical concepts are discussed in this context.

  1. Long-distance pulse propagation on high-frequency dissipative nonlinear transmission lines/resonant tunneling diode line cascaded maps

    International Nuclear Information System (INIS)

    Klofai, Yerima; Essimbi, B Z; Jaeger, D

    2011-01-01

    Pulse propagation on high-frequency dissipative nonlinear transmission lines (NLTLs)/resonant tunneling diode line cascaded maps is investigated for long-distance propagation of short pulses. Applying perturbative analysis, we show that the dynamics of each line is reduced to an expanded Korteweg-de Vries-Burgers equation. Moreover, it is found by computer experiments that the soliton developed in NLTLs experiences an exponential amplitude decay on the one hand and an exponential amplitude growth on the other. As a result, the behavior of a pulse in special electrical networks made of concatenated pieces of lines is closely similar to the transmission of information in optical/electrical communication systems.

  2. Nonlinear Seismic Behavior of Different Boundary Conditions of Transmission Line Systems under Earthquake Loading

    Directory of Open Access Journals (Sweden)

    Li Tian

    2016-01-01

    Full Text Available Nonlinear seismic behaviors of different boundary conditions of transmission line system under earthquake loading are investigated in this paper. The transmission lines are modeled by cable element accounting for the nonlinearity of the cable. For the suspension type, three towers and two span lines with spring model (Model 1 and three towers and four span lines’ model (Model 2 are established, respectively. For the tension type, three towers and two span lines’ model (Model 3 and three towers and four span lines’ model (Model 4 are created, respectively. The frequencies of the transmission towers and transmission lines of the suspension type and tension type are calculated, respectively. The responses of the suspension type and tension type are investigated using nonlinear time history analysis method, respectively. The results show that the responses of the transmission tower and transmission line of the two models of the suspension type are slightly different. However, the responses of transmission tower and transmission line of the two models of the tension type are significantly different. Therefore, in order to obtain accurate results, a reasonable model should be considered. The results could provide a reference for the seismic analysis of the transmission tower-line system.

  3. MITIGACIÓN DE CAMPO MAGNÉTICO DE LÍNEAS DE TRANSMISIÓN UTILIZANDO BUCLES PASIVOS MITIGAÇÃO DE CAMPO MAGNÉTICO DE LINHAS DE TRANSMISSÃO UTILIZANDO BUCLES PASSIVOS MAGNETIC FIELD MITIGATION OF TRANSMISSION LINES USING PASSIVE LOOPS

    Directory of Open Access Journals (Sweden)

    Diego Raúl Cadavid

    2010-07-01

    Full Text Available En este artículo se presenta un método simple para determinar el campo magnético generado por líneas de transmisión. El cálculo del campo magnético tiene en cuenta los efectos de mitigación de bucles pasivos, incluyendo su ubicación óptima en la línea mediante la aplicación de algoritmos genéticos. Los resultados de los cálculos son validados mediante reportes de casos publicados en el IEEE, software de análisis de campo electromagnético y datos experimentales arrojados de una implementación realizada en las líneas de alimentación de las torres de iluminación en un estadio. Luego del análisis, se demuestra la validez del método y la factibilidad de aplicarlo en líneas de transmisión del sistema de potencia.Neste artigo se apresenta um método simples para determinar o campo magnético gerado por linhas de transmissão. O cálculo do campo magnético leva em conta os efeitos de mitigação de loops passivos, incluindo sua localização ótima na linha mediante a aplicação de algoritmos genéticos. Os resultados dos cálculos são validados mediante reportes de casos publicados no IEEE, software de análise de campo eletromagnético e dados experimentais arrojados de uma implementação realizada nas linhas de alimentação das torres de iluminação em um estádio. Depois da análise, se demonstra a validade do método e a factibilidade de aplicá-lo em linhas de transmissão do sistema de potência.A simple method to determine the magnetic field generated by transmission lines is presented in this paper. The magnetic field calculation takes into account the mitigating effects of passive loops, including their optimal position in the line by applying genetic algorithms. Calculations results are validated by case reports published in the IEEE Transactions, software package for electromagnetic field analysis, and experimental data obtained from an implementation made in the power lines at a stadium lighting tower. After

  4. Line Capacity Expansion and Transmission Switching in Power Systems With Large-Scale Wind Power

    DEFF Research Database (Denmark)

    Villumsen, Jonas Christoffer; Bronmo, Geir; Philpott, Andy B.

    2013-01-01

    In 2020 electricity production from wind power should constitute nearly 50% of electricity demand in Denmark. In this paper we look at optimal expansion of the transmission network in order to integrate 50% wind power in the system, while minimizing total fixed investment cost and expected cost...... of power generation. We allow for active switching of transmission elements to reduce congestion effects caused by Kirchhoff's voltage law. Results show that actively switching transmission lines may yield a better utilization of transmission networks with large-scale wind power and increase wind power...... penetration. Furthermore, it is shown that transmission switching is likely to affect the optimal line capacity expansion plan....

  5. Magnetic Field Line Escape: Comparison with Mean Free Path

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Caroline G L; De Carvalho, R Egydio [UNESP-Univ Estadual Paulista, Instituto de Geociencias e Ciencias Exatas, Departamento de Estatistica, Matematica Aplicada e Computacao, Av. 24A, 1515, 13506-900 Rio Claro, SP (Brazil); Roberto, M [Instituto Tecnologico da Aeronautica, Departamento de Fisica 12228-900 Sao Jose dos Campos, SP (Brazil); Caldas, I L, E-mail: carolinegameiro@gmail.com, E-mail: marisar@ita.br, E-mail: ibere@if.usp.br, E-mail: regydio@rc.unesp.br [Universidade de Sao Paulo, Instituto de Fisica 05315-970 Sao Paulo, SP (Brazil)

    2011-03-01

    In the present work, we determine the fraction of magnetic field lines that reach the tokamak wall leaving the plasma surrounded by a chaotic layer created by resonant perturbations at the plasma edge. The chaotic layer arises in a scenario where an integrable magnetic field with reversed magnetic shear is perturbed by an ergodic magnetic limiter. For each considered line, we calculate its connection length, i.e. the number of toroidal turns that the field lines complete before reaching the wall. We represent the results in the poloidal section in which the initial coordinates are chosen. We also estimate the radial profile of the fraction of field lines, for different temperatures, whose connection lengths are smaller than the electron collisional mean free path.

  6. Characteristics of a four element gyromagnetic nonlinear transmission line array high power microwave source

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, J. M., E-mail: jared.johnson@ttu.edu; Reale, D. V.; Garcia, R. S.; Cravey, W. H.; Neuber, A. A.; Dickens, J. C.; Mankowski, J. J. [Center for Pulsed Power and Power Electronics Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas 79409 (United States); Krile, J. T. [Department of Electromagnetics and Sensor Systems, Naval Surface Warfare Center - Dahlgren Division, Dahlgren, Virginia 22448 (United States)

    2016-05-15

    In this paper, a solid-state four element array gyromagnetic nonlinear transmission line high power microwave system is presented as well as a detailed description of its subsystems and general output capabilities. This frequency agile S-band source is easily adjusted from 2-4 GHz by way of a DC driven biasing magnetic field and is capable of generating electric fields of 7.8 kV/m at 10 m correlating to 4.2 MW of RF power with pulse repetition frequencies up to 1 kHz. Beam steering of the array at angles of ±16.7° is also demonstrated, and the associated general radiation pattern is detailed.

  7. The limitation of the Slew Rate, as attenuator of effects of transmission line

    International Nuclear Information System (INIS)

    Rodriguez V, Luis Alfonso; Lopez Q, Jose German

    1999-01-01

    Transmission line effects in circuits of all kinds are becoming more notorious due to increased speeds of the signals traveling through them and also because of the circuits, which act upon them. A technique which is ready available to minimize the unwanted effects of transmission line behavior on the part of the circuits and lines involved, is to limit the Slew - Rate of the drivers used throughout. This paper undertakes an analysis of such a technique from the standpoint of frequencies as far as the benefits accrued from the used of slew rate limiting in the presence of transmission line effects

  8. Numerical determination of the magnetic field line Hamiltonian

    International Nuclear Information System (INIS)

    Kuo-Petravic, G.; Boozer, A.H.

    1986-03-01

    The structure of a magnetic field is determined by a one-degree of freedom, time-dependent Hamiltonian. This Hamiltonian is evaluated for a given field in a perturbed action-angle form. The location and the size of magnetic islands in the given field are determined from Hamiltonian perturbation theory and from an ordinary Poincare plot of the field line trajectories

  9. STUDY OF TRANSMISSION LINES EFFECT ON THE SYSTEM OPERATIONON OF CONTINUOUS AUTOMATIC CAB SIGNALLING

    Directory of Open Access Journals (Sweden)

    O. O. Hololobova

    2014-10-01

    Full Text Available Purpose. To conduct an effect research of the electromagnetic field of high-voltage transmission lines (HVTL (750 kV, 50 Hz on the track circuits and continuous automatic cab signalling (CACS with a signal current of 50 Hz in the areas of convergence and intersection with the transmission lines and to propose possible methods to improve noise immunity of CACS. Methodology. The measurements were performed both by means of car-laboratory and directly on rail lines. During the study the electric field strength in the range of industrial frequency directly under the transmission lines and at the distance from it to the railway lines was measured, as well as the time dependence of CACS codes with signal current frequency of 50 Hz directly under the transmission lines and at a distance from it in the absence of the train and its passing. Findings. The root causes analysis of CACS faults and failures was carried out. The effect of the electromagnetic field of high-voltage transmission lines (750 kV, 50 Hz on the track circuit and CACS with signal current of 50 Hz in the areas of convergence and intersection with the transmission line was investigated. Possible methods to improve noise immunity of CACS were considered. Originality. The effect research of transmission lines (750 kV on the operation of the automatic cab signalling on spans Prishib-Burchatsk and Privolnoye-Yelizarovo, Pridneprovsk railway in places of oblique railroads crossing and transmission lines (750 kV, 50 Hz was conducted. Electric field strength in the range of industrial frequency directly under the transmission lines and at a distance from it to the railway line, as well as the time dependences of ALSN codes with signal current frequency of 50 Hz directly under the transmission lines and at a distance from it in the absence of the train and as its passing were measured. It was found that CACS codes in track circuits under transmission lines are strongly distorted, as strength

  10. On increasing the spectral efficiency and transmissivity in the data transmission channel on the spacecraft-ground tracking station line

    Science.gov (United States)

    Andrianov, M. N.; Kostenko, V. I.; Likhachev, S. F.

    2018-01-01

    The algorithms for achieving a practical increase in the rate of data transmission on the space-craft-ground tracking station line has been considered. This increase is achieved by applying spectral-effective modulation techniques, the technology of orthogonal frequency compression of signals using millimeterrange radio waves. The advantages and disadvantages of each of three algorithms have been revealed. A significant advantage of data transmission in the millimeter range has been indicated.

  11. Improved field free line magnetic particle imaging using saddle coils.

    Science.gov (United States)

    Erbe, Marlitt; Sattel, Timo F; Buzug, Thorsten M

    2013-12-01

    Magnetic particle imaging (MPI) is a novel tracer-based imaging method detecting the distribution of superparamagnetic iron oxide (SPIO) nanoparticles in vivo in three dimensions and in real time. Conventionally, MPI uses the signal emitted by SPIO tracer material located at a field free point (FFP). To increase the sensitivity of MPI, however, an alternative encoding scheme collecting the particle signal along a field free line (FFL) was proposed. To provide the magnetic fields needed for line imaging in MPI, a very efficient scanner setup regarding electrical power consumption is needed. At the same time, the scanner needs to provide a high magnetic field homogeneity along the FFL as well as parallel to its alignment to prevent the appearance of artifacts, using efficient radon-based reconstruction methods arising for a line encoding scheme. This work presents a dynamic FFL scanner setup for MPI that outperforms all previously presented setups in electrical power consumption as well as magnetic field quality.

  12. Performance Evaluation on Transmission Tower-Line System with Passive Friction Dampers Subjected to Wind Excitations

    Directory of Open Access Journals (Sweden)

    Bo Chen

    2015-01-01

    Full Text Available The vibration control and performance evaluation on a transmission-tower line system by using friction dampers subjected to wind excitations are carried out in this study. The three-dimensional finite element (FE model of a transmission tower is firstly constructed. A two-dimensional lumped mass model of a transmission tower is developed for dynamic analysis. The analytical model of transmission tower-line system is proposed by taking the dynamic interaction between the tower and the transmission lines into consideration. The mechanical model of passive friction damper is presented by involving the effects of damper axial stiffness. The equation of motion of the transmission tower-line system incorporated with the friction dampers disturbed by wind excitations is established. A real transmission tower-line system is taken as an example to examine the feasibility and reliability of the proposed control approach. An extensive parameter study is carried out to find the optimal parameters of friction damper and to assess the effects of slipping force axial stiffness and hysteresis loop on control performance. The work on an example structure indicates that the application of friction dampers with optimal parameters could significantly reduce wind-induced responses of the transmission tower-line system.

  13. Evaluation of Characteristics of Lightning Faults on 275kV Transmission Lines

    Science.gov (United States)

    Kawamura, Hironao; Itamoto, Naoki; Shinjo, Kazuo; Ishii, Masaru

    It is effective to design the lightning protection of transmission lines by employing simulation to be able to reproduce conditions of experienced lightning faults. As a result of the lightning faults on 275kV transmission lines in Hokuriku area, the frequency of only one-ground fault of upper or middle lines is higher. Especially, the frequency of one-ground faults of the middle lines in summer is the highest. It is thought that many one-ground faults in summer are caused by direct lightning strokes to phase conductors. Moreover, multi-ground faults caused by lightning strokes to tower tops or overhead ground wires also include many ground faults of the middle lines. In this paper, the experienced lightning faults on the 275kV transmission lines are reproduced by EMTP calculations and the characteristics of the ground-fault lines are examined.

  14. SYNTHESIS OF ACTIVE SCREENING SYSTEM OF MAGNETIC FIELD OF HIGH VOLTAGE POWER LINES OF DIFFERENT DESIGN TAKING INTO ACCOUNT SPATIAL AND TEMPORAL DISTRIBUTION OF MAGNETIC FIELD

    Directory of Open Access Journals (Sweden)

    B.I. Kuznetsov

    2017-04-01

    Full Text Available Purpose. Analyze the spatial and temporal distribution of the magnetic field of high voltage power lines with different design allowing and development of recommendations for the design of active screening systems by magnetic field of high voltage power lines. Methodology. Analysis of the spatial and temporal distribution of the magnetic field of high voltage power lines of different design allowing is made on the basis of Maxwell's equations solutions in the quasi-stationary approximation. Determination of the number, configuration, spatial arrangement and the compensation coil currents is formulated in the form of multiobjective optimization problem that is solved by multi-agent multiswarm stochastic optimization based on Pareto optimal solutions. Results of active screening system for the synthesis of various types of transmission lines with different numbers of windings controlled. The possibility of a significant reduction in the level of the flux density of the magnetic field source within a given region of space. Originality. For the first time an analysis of the spatial and temporal distribution of the magnetic field of power lines with different types and based on findings developed recommendations for the design of active screening system by magnetic field of high voltage power lines. Practical value. Practical recommendations on reasonable choice of the number and spatial arrangement of compensating windings of active screening system by magnetic field of high voltage power lines of different design allowing for the spatial and temporal distribution of the magnetic field. Results of active screening system synthesis of the magnetic field of industrial frequency generated by single-circuit 110 kV high voltage power lines with the supports have 330 - 1T «triangle» rotating magnetic field with full polarization in a residential five-storey building, located near the power lines. The system contains three compensating coil and reduces

  15. AA, sandwich line with magnetic horn

    CERN Multimedia

    CERN PhotoLab

    1980-01-01

    Continuation from 8010293: Finally, the sandwich line with the horn is placed on the ground, for the horn to be inspected and, if needed, exchanged for a new one. The whole procedure was trained with several members of the AA team, for quick and safe handling, and to share the radiation dose amongst them.

  16. Planning Electric Transmission Lines: A Review of Recent Regional Transmission Plans

    Energy Technology Data Exchange (ETDEWEB)

    Eto, Joseph H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-04-13

    The first Quadrennial Energy Review (QER) recommends that the U.S. Department of Energy (DOE) conduct a national review of transmission plans and assess the barriers and incentives to their implementation. DOE tasked Lawrence Berkeley National Laboratory (LBNL) to prepare two reports to support the agency’s response to this recommendation. This report reviews regional transmission plans and regional transmission planning processes that have been directed by Federal Energy Regulatory Commission (FERC) Order Nos. 890 and 1000. We focus on the most recent regional transmission plans (those issued in 2015 and through approximately mid-year 2016) and current regional transmission planning processes. A companion report focuses on non-plan-related factors that affect transmission projects.

  17. An Efficient Algorithm for Fault Location on Mixed Line-Cable Transmission Corridors

    NARCIS (Netherlands)

    Popov, M.; Rietveld, G.; Radojevic, Z.; Terzija, V.

    2013-01-01

    This paper presents a fault location algorithm that can be used to accurately locate the fault at any place along mixed line-cable transmission corridors. The algorithm is an impedance based line/cable parameter dependent algorithm. The fault location algorithm is derived using distributed line

  18. Research on UAV Intelligent Obstacle Avoidance Technology During Inspection of Transmission Line

    Science.gov (United States)

    Wei, Chuanhu; Zhang, Fei; Yin, Chaoyuan; Liu, Yue; Liu, Liang; Li, Zongyu; Wang, Wanguo

    Autonomous obstacle avoidance of unmanned aerial vehicle (hereinafter referred to as UAV) in electric power line inspection process has important significance for operation safety and economy for UAV intelligent inspection system of transmission line as main content of UAV intelligent inspection system on transmission line. In the paper, principles of UAV inspection obstacle avoidance technology of transmission line are introduced. UAV inspection obstacle avoidance technology based on particle swarm global optimization algorithm is proposed after common obstacle avoidance technologies are studied. Stimulation comparison is implemented with traditional UAV inspection obstacle avoidance technology which adopts artificial potential field method. Results show that UAV inspection strategy of particle swarm optimization algorithm, adopted in the paper, is prominently better than UAV inspection strategy of artificial potential field method in the aspects of obstacle avoidance effect and the ability of returning to preset inspection track after passing through the obstacle. An effective method is provided for UAV inspection obstacle avoidance of transmission line.

  19. A Novel Design of Radio Frequency Energy Relays on Power Transmission Lines

    Directory of Open Access Journals (Sweden)

    Jin Tong

    2016-06-01

    Full Text Available In this paper, we investigate the energy problem of monitoring sensors on high-voltage power transmission lines and propose a wireless charging scheme for a Radio Frequency IDentification (RFID sensor tag to solve a commercial efficiency problem: the maintenance-caused power outage. Considering the environmental influences on power transmission lines, a self-powered wireless energy relay is designed to meet the energy requirement of the passive RFID sensor tag. The relay can obtain the electric field energy from the transmission lines and wirelessly power the RFID sensor tags around for longer operating distance. A prototype of the energy relay is built and tested on a 110 kv line. The measurement results show that the energy relay can provide stable energy even with the influences of wind, noise and power outage. To our knowledge, it is the first work to power the RFID sensor tags on power transmission lines.

  20. CORONA EFFECTS NUMERICAL SIMULATION IN SINGLE PHASE TRANSMISSION LINES

    OpenAIRE

    MARCOS ANDRE DA FROTA MATTOS

    1985-01-01

    Uma análise teórica, comparativa e de sensibilidade é feita com quatro modelos básicos para o efeito corona em linhas de transmissão monofásicas. A análise de ocorrência de choque em linhas de transmissão é também considerada na análise os modelos. Um algoritmo computacional é desenvolvido para estudo de transitórios eletromagnéticos em linhas de transmissão monofásicas. Por fim são analisados casos interessantes do ponto de vista da Engenharia Elétrica. The corona effect on monophasic tra...

  1. Ultrasound transmission spectroscopy: in-line sizing of nanoparticles

    NARCIS (Netherlands)

    Neer, P.L.M.J. van; Volker, A.W.F.; Pierre, G.; Bouvet, F.; Crozat, S.

    2014-01-01

    Nanoparticles are increasingly used in a number of applications, e.g. coatings or paints. To optimize nanoparticle production in-line quantitative measurements of their size distribution and concentration are needed. Ultrasound-based methods are especially suited for in-line particle sizing. These

  2. Wideband Isolation by Frequency Conversion in a Josephson-Junction Transmission Line

    Science.gov (United States)

    Ranzani, Leonardo; Kotler, Shlomi; Sirois, Adam J.; DeFeo, Michael P.; Castellanos-Beltran, Manuel; Cicak, Katarina; Vale, Leila R.; Aumentado, José

    2017-11-01

    Nonreciprocal transmission and isolation at microwave frequencies are important in many practical applications. In particular, compact isolators are useful in protecting sensitive quantum circuits operating at cryogenic temperatures from amplifier backaction and other environmental noise such as black-body radiation from higher temperature stages. However, the size of commercial cryogenic isolators limits the ability to measure multiple quantum circuits because of space constraints in typical dilution refrigerator systems. Furthermore, isolators usually require the use of ferrite components that cannot be integrated at the chip level and, since they also need large biasing magnetic fields, are incompatible with superconducting quantum circuits. In this work we show one way to accomplish isolation in a superconducting chip-scale device, a traveling-wave unidirectional frequency converter based on a parametrically pumped superconducting Josephson-junction transmission line, demonstrating better than 4.8 dB of inferred signal isolation from 6.6 to 11.4 GHz, with a maximum of 12 dB at 9.5 GHz. By using frequency diplexing techniques a conventional isolator could be implemented over this bandwidth.

  3. Use of Rod Compactors for High Voltage Overhead Power Lines Magnetic Field Mitigation

    Directory of Open Access Journals (Sweden)

    Fabio Bignucolo

    2017-09-01

    Full Text Available In the last decades, strengthening the high voltage transmission system through the installation of new overhead power lines has become critical, especially in highly developed areas. Present laws concerning the human exposure to electric and magnetic fields introduce constraints to be considered in both new line construction and existing systems. In the paper, a technique for passive magnetic field mitigation in areas close to overhead power lines is introduced, fully modelled and discussed through a parametric analysis. The investigated solution, which basically consists in approaching line conductors along the span making use of rod insulators, is applicable on both existing and under-design overhead lines as an alternative to other mitigating actions. Making use of a 3-dimensional representation, the procedure computes both positions of phase conductors and forces acting on insulators, towers, conductors and compactors, with the aim of evaluating the additional mechanical stress introduced by the compactors. Finally, a real case study is reported to demonstrate and quantify the benefits in terms of ground magnetic field reduction achievable by applying the proposed solution, in comparison to a traditional configuration. Furthermore, using compactors to passively reduce the magnetic field is simple to be applied, minimally invasive and quite inexpensive as regards to alternative mitigating actions.

  4. [Evaluation of reports on environmental measurements of electromagnetic fields generated by high voltage transmission lines and substations].

    Science.gov (United States)

    Szuba, Marek

    2007-01-01

    This paper presents some situations, in which measurements of electromagnetic fields generated by transmission lines and substations should be performed. The range of measurements may differ, but maximum values of electric and magnetic fields and flux density must be identified in all situations. The area with electric field exceeding 1 kV/m should be identified as well. The author also presents basic requirements to be met by the measurement technique. These requirements are specified according to the national standard. Special attention should be paid to the identification of the spatial distribution of electric field and flux density generated in the vicinity of high voltage transmission lines. To verify the measurement results, it is necessary to calculate the distribution of both aforesaid field components. For environmental protection purposes, it is also proposed that the report should include measurements of electromagnetic fields of 50 Hz along with calculated results presented in tables and diagrams.

  5. Metastable memristive lines for signal transmission and information processing applications

    Science.gov (United States)

    Slipko, Valeriy A.; Pershin, Yuriy V.

    2017-04-01

    Traditional studies of memristive devices have mainly focused on their applications in nonvolatile information storage and information processing. Here, we demonstrate that the third fundamental component of information technologies—the transfer of information—can also be employed with memristive devices. For this purpose, we introduce a metastable memristive circuit. Combining metastable memristive circuits into a line, one obtains an architecture capable of transferring a signal edge from one space location to another. We emphasize that the suggested metastable memristive lines employ only resistive circuit components. Moreover, their networks (for example, Y-connected lines) have an information processing capability.

  6. Origin of Magnetism in Hydrothermally Aged 2-Line Ferrihydrite Suspensions.

    Science.gov (United States)

    Cao, Liang; Jiang, Zhao-Xia; Du, Yong-Hua; Yin, Xin-Mao; Xi, Shi-Bo; Wen, Wen; Roberts, Andrew P; Wee, Andrew T S; Xiong, Yi-Min; Liu, Qing-Song; Gao, Xing-Yu

    2017-03-07

    As an iron oxyhydroxide, nanosized ferrihydrite (Fh) is important in Earth science, biology, and industrial applications. However, its basic structure and origin of its magnetism have long been debated. We integrate synchrotron-based techniques to explore the chemical structures of 2-line ferrihydrite and to determine the origin of its magnetism during hydrothermal aging in air. Our results demonstrate that both the magnetism and X-ray magnetic circular dichroism (XMCD) signal of 2-line ferrihydrite are enhanced with aging time, and that XMCD spectral patterns resemble that of maghemite (γ-Fe 2 O 3 ) rather than magnetite (Fe 3 O 4 ). Fe L-edge and K-edge X-ray absorption spectroscopy (XAS) further indicate formation of both maghemite and hematite (α-Fe 2 O 3 ) with increasing concentrations with longer hydrothermal aging time. Thus, magnetic enhancement with longer hydrothermal aging time is attributed to increasing maghemite concentration instead of a magnetically ordered ferrihydrite as previously reported. Moreover, L-edge and K-edge XAS spectra with different probing depths yield different ratios of these Fe oxides, which suggest the formation of a core (ferrihydrite-rich)-shell (with a mixture of both allotropes; α-Fe 2 O 3 and γ-Fe 2 O 3 ) structure during hydrothermal aging. Our results provide insights into the chemical evolution of 2-line ferrihydrite that reveal unambiguously the origin of its magnetism.

  7. Magnet Lattice Design for the Transmission of Power Using Particle Beams

    Energy Technology Data Exchange (ETDEWEB)

    Marley, Daniel; /North Carolina State U. /SLAC

    2012-08-24

    As the amount of electricity generated by renewable energy sources continues to increase, the current method of power transmission will not serve as an adequate method for transmitting power over very long distances. A new method for transmitting power is proposed using particle beams in a storage ring. Particle beams offer an incredibly energy efficient alternative to transmission lines in transmitting power over very long distances. A thorough investigation of the magnet lattice design for this storage ring is presented. The design demonstrates the ability to design a ring with stable orbits over a 381.733 km circumference. Double bend achromats and FODO cells are implemented to achieve appropriate {beta} functions and dispersion functions for 9-11 GeV electron beams.

  8. Measurement-Based Transmission Line Parameter Estimation with Adaptive Data Selection Scheme

    DEFF Research Database (Denmark)

    Li, Changgang; Zhang, Yaping; Zhang, Hengxu

    2017-01-01

    Accurate parameters of transmission lines are critical for power system operation and control decision making. Transmission line parameter estimation based on measured data is an effective way to enhance the validity of the parameters. This paper proposes a multi-point transmission line parameter...... of the proposed model. Some 500kV transmission lines from a provincial power system of China are estimated to demonstrate the applicability of the presented model. The superiority of the proposed model over fixed data selection schemes is also verified....... estimation model with an adaptive data selection scheme based on measured data. Data selection scheme, defined with time window and number of data points, is introduced in the estimation model as additional variables to optimize. The data selection scheme is adaptively adjusted to minimize the relative...

  9. Using ice melting and ice rolling technologies to remove ice from sub-transmission and transmission lines at Manitoba Hydro

    International Nuclear Information System (INIS)

    Farias, A. R.

    1999-01-01

    Development of an of an Ice Storm Management program by Manitoba Hydro to reduce ice storm damage to its 8 kV feeders to 115 kV transmission lines, is discussed. The program consists of the de-icing of overhead lines, either by ice melting, or ice rolling. Ice melting involves the placement of a three-phase short at a calculated point. The term ice rolling denotes a process of mechanically stripping the ice from conductors. The most recent major ice storm experienced by Manitoba Hydro was in the winter of 1997/1998. During the period from February 6 to February 17, 1998, a total of 83 'ice melt' procedures were performed to melt the ice from 2,628 km of overhead line (7,883 km of conductor), in addition to 'ice rolling'. This paper describes Manitoba Hydro's 25-years' experience with ice melting and it also describes the advantages and disadvantages of both ice melting and ice rolling. Although not a panacea to combat the effects of ice storms, ice melting was found to be the most effective way of removing ice from overhead transmission and sub-transmission lines. Ice rolling was also found to be effective. Other tools that have been found to be useful by various utilities in combating ice storm damage include improved structure and line design, system design that provide more redundancies and emergency sources, and standby generators at critical load points

  10. Brazilian production development of class 2 polymeric surge arresters for transmission line application

    Energy Technology Data Exchange (ETDEWEB)

    Dellallibera, Adriano A. [Industria Eletromecanica Balestro, Mogi Mirim, SP (Brazil)], E-mail: adrianoad@balestro.com; Andrade, Antonio Donizetti de; Bezerra, Ana Cristina Guara; Duarte, Jose Vicente Pereira; Gois, Paulo Marcio Batista; Markiewicz, Rubens Leopoldo [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil)], Emails: andonize@cemig.com.br, anacris@cemig.com.br, vicente@cemig.com.br, pgois@cemig.com.br, rlmark@cemig.com.br

    2007-07-01

    This paper shows the steeps of Brazilian class 2 ZnO lightning surge arrester development and production, aiming to attend the goal of CEMIG transmission lines performance improvement against lightning discharges action. The description of CEMIG transmission lines performance, before and after the ZnO lightning arresters installation, the necessity of use of ZnO lightning surge arrester, the prototypes manufacture, tests, problems and solutions are presented. (author)

  11. Overvoltage Propagation from Transmission Line into Transformer Winding

    Directory of Open Access Journals (Sweden)

    Vaclav Kotlan

    2015-01-01

    Full Text Available The paper deals with very fast transient phenomena in a system consisting of two parts: a cable line and a transformer winding. In this case an adequate model should be considered as a circuit with distributed parameters. Its description is given by a system of partial differential equations of hyperbolic type. Our approach is based on a numerical solution in the time domain and the method FDTD has been used. It allows obtaining results in a form of time-space voltage and current wave distribution along the cable line and the transformer winding. This distribution is depending on many factors some of them were studied in this paper.

  12. On the Relation between Composite Right-/Left-Handed Transmission Lines and Chebyshev Filters

    Directory of Open Access Journals (Sweden)

    Changjun Liu

    2009-01-01

    Full Text Available Composite right-/left-handed (CRLH transmission lines have gained great interest in the microwave community. In practical applications, such CRLH sections realized by series and shunt resonators have a finite length. Starting from the observation that a high-order Chebyshev filter also exhibits a periodic central section of very similar structure, the relations between finite length CRHL transmission lines and Chebyshev filters are discussed in this paper. It is shown that a finite length CRLH transmission line in the balanced case is equivalent to the central part of a low-ripple high-order Chebyshev band-pass filter, and a dual-CRLH transmission line in the balanced case is equivalent to a low-ripple high-order Chebyshev band-stop filter. The nonperiodic end sections of a Chebyshev filter can be regarded as matching sections, thus leading to an even better amplitude and phase response. It is also shown that, equally to a CRHL transmission line, a Chebyshev filter exhibits negative phase velocity in part of its passband. As a consequence, an improved behavior of finite length CRLH transmission lines may be achieved adding matching sections based on filter theory; this is demonstrated by a simulation example.

  13. Analysis of Power Network for Line Reactance Variation to Improve Total Transmission Capacity

    Directory of Open Access Journals (Sweden)

    Ikram Ullah

    2016-11-01

    Full Text Available The increasing growth in power demand and the penetration of renewable distributed generations in competitive electricity market demands large and flexible capacity from the transmission grid to reduce transmission bottlenecks. The bottlenecks cause transmission congestion, reliability problems, restrict competition, and limit the maximum dispatch of low cost generations in the network. The electricity system requires efficient utilization of the current transmission capability to improve the Available Transfer Capability (ATC. To improve the ATC, power flow among the lines can be managed by using Flexible AC Transmission System (FACTS devices as power flow controllers, which alter the parameters of power lines. It is important to place FACTS devices on suitable lines to vary the reactance for improving Total Transmission Capacity (TTC of the network and provide flexibility in the power flow. In this paper a transmission network is analyzed based on line parameters variation to improve TTC of the interconnected system. Lines are selected for placing FACTS devices based on real power flow Performance Index (PI sensitivity factors. TTC is computed using the Repeated Power Flow (RPF method using the constraints of lines thermal limits, bus voltage limits and generator limits. The reactance of suitable lines, selected on the basis of PI sensitivity factors are changed to divert the power flow to other lines with enough transfer capacity available. The improvement of TTC using line reactance variation is demonstrated with three IEEE test systems with multi-area networks. The results show the variation of the selected lines’ reactance in improving TTC for all the test networks with defined contingency cases.

  14. 75 FR 25195 - Kake to Petersburg Transmission Line Intertie Project

    Science.gov (United States)

    2010-05-07

    ... Frederick Sound. At Frederick Sound, a submarine cable termination facility would connect the overhead line to a 3.1 mile long underwater cable, which would come ashore near Prolewy Point on Kupreanof Island... Wrangell Narrows via a horizontal directional bore or buried cable that would extend approximately 1,400...

  15. Induction effect of an electromagnetic pulse on transmission line

    International Nuclear Information System (INIS)

    Pazirandeh, A.; Maleki, P.; Sardari, D.

    2004-01-01

    Ever increasing demand for and vital importance of communication systems and power transmission to our industries, transportation to work, hospitals, and many other important places deemed necessary to have safety based design considerations. Many natural phenomena and man-made devices may generate powerful and intensive EMP, which is very harmful to the safe mode operation of electrical and communicational systems. In this paper we have calculated induced electric field and power induction due to lightening, nuclear explosion and similar events to the aerial and underground cables

  16. Fresnel equations and transmission line analogues for diffraction gratings

    Energy Technology Data Exchange (ETDEWEB)

    Kaushik, S.

    1995-08-01

    A simple and intuitive formalism is presented to describe diffraction in multi-layered periodic structures. We use the well known results from scalar analysis (wave propagation in homogeneous layered media) and show that they can be generalized rather readily to vector problems such as diffraction analysis. Specifically, we derive: (1) generalized Fresnel equations appropriate for reflection and transmission from an infinitely thick grating, (2) a generalized Airy formula for thin-film to describe reflection and transmission of light through a lamellar grating and (3) a matrix propagation method akin to that used for multi-layer thin film analysis. The results developed here complement the recent work on R-matrix and S-matrix propagation algorithms that have been used in connection with modal and differential grating theories. These algorithms have proven to be numerically stable for calculating diffraction efficiencies from deep groove gratings. The formalism developed here expands upon the earlier literature by providing important details that are hitherto unavailable.

  17. California-Oregon 500-kV transmission line development of design criteria

    International Nuclear Information System (INIS)

    Simpson, K.D.

    1990-01-01

    The California-Oregon Transmission Project (COTP) encompassed the design and construction of a third 500-kV ac intertie between California and the Pacific Northwest Transmission system. Sargent ampersand Lundy's (S ampersand L) scope of work in the COTP includes the design of approximately 150 miles of new single-circuit, 500-kV transmission line from southern Oregon to the vicinity of Redding, California. This paper presents the development of the design criteria for this segment of the project, which crosses diverse topographic and climatic regions. This project is an example of the increasing utilization of computers in transmission line engineering. Almost all aspects of design involved the use of the computer. Also, the development of the design criteria for this project coincided with an early release of the TLWorkstation software package by EPRI. TLWorkstation is an engineering workstation containing a family of programs for various aspects of transmission line design. This engineering software allows for increasing refinement in the design and economic optimization of transmission lines and is becoming an important design tool for transmission engineers

  18. Insulator and Clerance Requirements in Overhead Line Transmission Systems without Shield Wires

    DEFF Research Database (Denmark)

    Sørensen, Thomas Kjærsgaard; Holbøll, Joachim

    2008-01-01

    This paper theoretically examines the required insulation lengths and clearances in 400 kV overhead line systems when not making use of ground wires as lightning protection. The influence of lightning strikes to the system is investigated based on dynamic transmission line simulations of a 400 kV...

  19. Measuring the complex permittivity of poultry meat with a planar transmission-line sensor

    Science.gov (United States)

    A planar transmission-line sensor is used to measure the complex permittivity of chicken breast meat over the frequency range 0.5 – 5 GHz. Results for the permittivity of nine samples of chicken breast meat are compared to results obtained with a commercially available open-ended coaxial-line probe....

  20. Theoretical models of magnetic field line merging. I

    International Nuclear Information System (INIS)

    Vasyliunas, V.M.

    1975-01-01

    Models of magnetic field line merging that consider processes in a limited region around the magnetic X line, within which the external magnetic fields are roughly uniform and antiparallel, are reviewed. Part I describes the concept of magnetic merging and then considers the models based on a hydromagnetic approach. The models developed by Sweet and Parker, by Petschek, and by Sonnerup and Yeh and Axford are shown to be fundamentally consistent, representing different aspects of the same problem. The model of Sweet and Parker describes the small region around the neutral line where magnetic field diffusion is the dominant process. The inclusion of inertial as well as finite resistivity effects allows an extension of their model to collisionless plasmas. Petschek's model represents a system with a boundary condition of uniform field at the sides; it has been extended and formulated in a mathematically precise manner. The nonsingular model of Sonnerup and of Yeh and Axford has special boundary conditions at the sides producing localized slow mode MHD expansion fans in the external flow; the singular models and the compressible similarity models are physically unrealizable. The maximum merging rate corresponds to flow into the diffusion region of the local Alfven speed, which, however, can be made arbitrarily large by slow mode MHD expansion if suitable boundary condi []ions are present. (auth)

  1. The behavior of the magnetic lines of a rotating system

    International Nuclear Information System (INIS)

    Evangelidis, E.

    1977-01-01

    The behaviour of a magnetic line has been studied under continuous injection of plasma. Under increasing density the existence of three zones of possible concentration has been shown. For values greater than a critical value D=0, with D suitably defined, one zone disappears, whilst the other two degenerate into one. (Auth.)

  2. submitter Superconducting transmission lines – Sustainable electric energy transfer with higher public acceptance?

    CERN Document Server

    Thomas, Heiko; Chervyakov, Alexander; Stückrad, Stefan; Salmieri, Delia; Rubbia, Carlo

    2016-01-01

    Despite the extensive research and development investments into superconducting science and technology, both at the fundamental and at the applied levels, many benefits of superconducting transmission lines (SCTL) remain unknown to the public and decision makers at large. This paper aims at informing about the progress in this important research field. Superconducting transmission lines have a tremendous size advantage and lower total electrical losses for high capacity transmission plus a number of technological advantages compared to solutions based on standard conductors. This leads to a minimized environmental impact and enables an overall more sustainable transmission of electric energy. One of the direct benefits may be an increased public acceptance due to the low visual impact with a subsequent reduction of approval time. The access of remote renewable energy (RE) sources with high-capacity transmission is rendered possible with superior efficiency. That not only translates into further reducing $CO_2...

  3. Novel pulse amplifying circuits based on transmission lines of different characteristic impedance

    International Nuclear Information System (INIS)

    Belloni, F.; Doria, D.; Lorusso, A.; Nassisi, V.

    2006-01-01

    Two novel circuits used to amplify electric pulses by the coupling of transmission lines of different characteristic impedance are described. The circuits are intended for doubling voltage pulses and for doubling current pulses. The former is composed by a R 0 transmission line closed on a set of two 2R 0 storage lines connected in parallel, while the latter is composed by a R 0 transmission line closed on a set of two R 0 /2 storage lines connected in series. The length of every storage line is half of input-pulse length. In both circuits, one storage line is characterized by an open extremity and the other line by a closed extremity. Connecting opportunely the storage lines to suitable load resistors, 4R 0 and R 0 /4, for the circuit having parallel and series connected lines, respectively, a twice of the output pulse intensity is obtained. Such devices are very suitable to generate high intensity voltage and/or current peaks which are very interesting in the field of the accelerators. Both circuit behaviours have been theoretically studied and verified by computer simulations

  4. Transmission Characteristics of an OFDM signal for Power Line Communication System with High Bit Rate

    Science.gov (United States)

    Mori, Akira; Watanabe, Yosuke; Tokuda, Masamitsu; Kawamoto, Koji

    In this paper, we measured what influence the sinusoidal transmission characteristics of the electric power line with various forms gave to the transmission characteristic of OFDM (Orthogonal Frequency Division Multiplexing) signal through PLC (power line communication system) modem. We classified the electric power line transmission line with various forms in a real environment into two basic elements, which are an outlet type branch and a switch type branch. Next, PHY rate (Physical rate) is measured for each basic element connected with the PLC modem. At this time, the transmission characteristics of the electric power line are simulated from measured data. OFDM sending and receiving systems are composed on the computer, and the PHY rate is simulated. By comparing with measured and calculated values, it is revealed that PHY rate of PLC modem is most affected in the case of the power line transmission characteristics having broad band and high level attenuation and group delay variation, and is not affected in the case of that having narrow band attenuation and group delay variation.

  5. Optimization of Hellenic overhead high-voltage transmission lines lightning protection

    Energy Technology Data Exchange (ETDEWEB)

    Christodoulou, C.A.; Fotis, G.P.; Stathopulos, I.A. [National Technical University of Athens, School of Electrical and Computer Engineering, High Voltage Laboratory, 9 Iroon Politechniou Street, Zografou, 157 80 Athens (Greece); Ekonomou, L. [A.S.PE.T.E. - School of Pedagogical and Technological Education, Department of Electrical Engineering Educators, N. Heraklion, 141 21 Athens (Greece); Harkiolakis, N. [Hellenic American University, IT Faculty, 12 Kaplanon Street, 106 80 Athens (Greece)

    2009-04-15

    It is well known that the lightning protection of transmission lines is exclusively relying on their correct initial design. Although detailed engineering studies are usually performed by electric power utilities for the design of new transmission lines, there are reported cases where the design is based simply on tradition or on utilities' standardization policy. In this paper, the lightning protection of high-voltage transmission lines is faced as an optimization problem where optimum design parameters are calculated for the lines, relating their cost with the lightning failures' cost, aiming to reduce or even eliminate lightning failures. The optimization method considers all the available protection means, i.e. ground wires and surge arresters. In order to validate the effectiveness of the proposed method, it is applied on several operating Hellenic transmission lines of 150 kV carefully selected among others due to their high failure rates during lightning thunderstorms. The obtained optimum parameters, which reduce the failure rates caused by lightning are compared with the operating transmission lines' existing parameters showing the usefulness of the method, which can prove to be a valuable tool for the studies of electric power system designers. (author)

  6. Radiating nonuniform transmission-line systems and the partial element equivalent circuit method

    CERN Document Server

    Nitsch, Juergen; Wollenberg, Gunter

    2009-01-01

    High frequencies of densely packed modern electronic equipment turn even the smallest piece of wire into a transmission line with signal retardation, dispersion, attenuation, and distortion. In electromagnetic environments with high-power microwave or ultra-wideband sources, transmission lines pick up noise currents generated by external electromagnetic fields. These are superimposed on essential signals, the lines acting not only as receiving antennas but radiating parts of the signal energy into the environment. This book is outstanding in its originality. While many textbooks rephrase

  7. Experimental observation on asymmetric energy flux within the forbidden frequency band in the LC transmission line

    International Nuclear Information System (INIS)

    Tao Feng; Chen Weizhong; Pan Junting; Xu Wen; Du Sidan

    2012-01-01

    We study the energy flux in a nonlinear electrical transmission line consisting of two coupled segments which are identical in structure and different in parameters. The asymmetry of energy flux caused by nonlinear wave has been observed experimentally in the forbidden band of the line. The experiment shows whether the energy can flow through the transmission line depends on the amplitude of the boundary driving voltages, which can be well explained in the theoretical framework of nonlinear supratransmission. The numerical simulation based on Kirchhoff’s laws further verifies the existence of the asymmetric energy flux in the forbidden band.

  8. High temperature superconducting Josephson transmission lines for pulse and step sharpening

    International Nuclear Information System (INIS)

    Martens, J.S.; Wendt, J.R.; Hietala, V.M.; Ginley, D.S.; Ashby, C.I.H.; Plut, T.A.; Vawter, G.A.; Tigges, C.P.; Siegal, M.P.; Hou, S.Y.; Phillips, J.M.; Hohenwarter, G.K.G.

    1992-01-01

    An increasing number of high speed digital and other circuit applications require very narrow impulses or rapid pulse edge transitions. Shock wave transmission lines using series or shunt Josephson junctions are one way to generate these signals. Using two different high temperature superconducting Josephson junction processes (step-edge and electron beam defined nanobridges), such transmission lines have been constructed and tested at 77 K. Shock wave lines with approximately 60 YBaCuO nanobridges, have generated steps with fall times of about 10 ps. With step-edge junctions (with higher figures of merit but lower uniformity), step transition times have been reduced to an estimated 1 ps

  9. Multiplex Superconducting Transmission Line for green power consolidation on a Smart Grid

    Science.gov (United States)

    McIntyre, P.; Gerity, J.; Kellams, J.; Sattarov, A.

    2017-12-01

    A multiplex superconducting transmission line (MSTL) is being developed for applications requiring interconnection of multi-MW electric power generation among a number of locations. MSTL consists of a cluster of many 2- or 3-conductor transmission lines within a coaxial cryostat envelope. Each line operates autonomously, so that the interconnection of multiple power loads can be done in a failure-tolerant network. Specifics of the electrical, mechanical, and cryogenic design are presented. The consolidation of transformation and conditioning and the failure-tolerant interconnects have the potential to offer important benefit for the green energy components of a Smart Grid.

  10. Transmission line design for a power distribution system at 20 kHz for aircraft

    Science.gov (United States)

    Zelby, L. W.; Mathes, J. B.; Shawver, J. W.

    1986-01-01

    A low inductance, low characteristic impedance transmission line was designed for a 20 kHz power distribution system. Several different conductor configurations were considered: strip lines, interdigitated metal ribbons, and standard insulated wires in multiwire configurations (circular and rectangular cylindrical arrangements). The final design was a rectangular arrangement of multiple wires of the same gauge with alternating polarities from wire to wire. This offered the lowest inductance per unit length (on the order of several nanohenries/meter) and the lowest characteristic impedance (on the order of one Ohm). Standard multipin connectors with gold-plated elements were recommended with this transmission line, the junction boxes to be internally connected with flat metal ribbons for low inductance, and the line to be constructed in sections of suitable length. Computer programs for the calculation of inductance of multiwire lines and of capacitances of strip lines were developed.

  11. Modulational Instability in a Pair of Non-identical Coupled Nonlinear Electrical Transmission Lines

    Science.gov (United States)

    Eric, Tala-Tebue; Aurelien, Kenfack-Jiotsa; Marius Hervé, Tatchou-Ntemfack; Timoléon Crépin, Kofané

    2013-07-01

    In this work, we investigate the dynamics of modulated waves non-identical coupled nonlinear transmission lines. Traditional methods for avoiding mode mixing in identical coupled nonlinear electrical lines consist of adding the same number of linear inductors in each branch. Adding linear inductors in a single line leads to asymmetric coupled nonlinear electrical transmission lines which propagate the signal and the mode mixing. On one hand, the difference between the two lines induced the fission for only one mode of propagation. This fission is influenced by the amplitude of the signal and the amount of the input energy as well; it also narrows the width of the input pulse soliton, leading to a possible increasing of the bit rate. On the other hand, the dissymmetry of the two lines converts the network into a good amplifier for the ω_ mode which corresponds to the regime admitting low frequencies.

  12. Arcing Faults Location Methods for Power Transmission Lines

    Directory of Open Access Journals (Sweden)

    Mateusz Pustułka

    2014-03-01

    Full Text Available This paper presents three different fault location approaches: one-end Takagi algorithm, two-end algorithm considering natural fault loops and neural network. It is assumed that three-phase voltages and currents from both ends of the line measured asynchronously are the input signals of the fault locator. In addition to natural fault loop signals also the use of symmetrical components (positive and negative or incremental positive sequence components for fault location were considered. Results of the evaluation study have been included, analyzed and discussed. The impact of filtration has also been considered.

  13. Transmission Lines or Poles, Electric - VOLUSIA COUNTY MAJOR POWER LINES (Arcs)

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Volusia County Power Line data was aggregated by using parcel data and visual inspection of 2005 aerial photography to determine centerline of Power Lines Right of...

  14. Remote Control System of the TJ-II Microwave Transmission Lines Mirrors

    International Nuclear Information System (INIS)

    Lopez Sanchez, A.; Fernandez, A.; Cappa, A.; Gama, J. de la; Olivares, J.; Garcia, R.; Chamorro, M.

    2007-01-01

    The ECRH system of the TJ-II stellarator has two gyrotrons, which deliver a maximum power of 300 kW each at a frequency of 53.2 GHz. Another 28 GHz gyrotron will be used to heat the plasma by electron Bernstein waves (EBWH). The microwave power is transmitted from the gyrotrons to the vacuum chamber by two quasi-optical transmission lines for ECRH and a corrugated waveguide for EBWH. All transmission lines have an internal movable mirror inside the vacuum chamber to focus the beam and to be able to change the launching angle. The control of the beam polarization is very important and the lines have two corrugated mirrors, which actuate as polarizers. In this report the control system of the position of these three internal mirrors and the polarizers of the EBWH transmission line is described. (Author) 20 refs

  15. Probing photospheric magnetic fields with new spectral line pairs

    Science.gov (United States)

    Smitha, H. N.; Solanki, S. K.

    2017-12-01

    Context. The magnetic line ratio (MLR) method has been extensively used in the measurement of photospheric magnetic field strength. It was devised for the neutral iron line pair at 5247.1 Å and 5250.2 Å (5250 Å pair). Other line pairs as well-suited as this pair have not been reported in the literature. Aims: The aim of the present work is to identify new line pairs useful for the MLR technique and to test their reliability. Methods: We used a three-dimensional magnetohydrodynamic 3D MHD simulation representing the quiet Sun atmosphere to synthesize the Stokes profiles. Then, we applied the MLR technique to the Stokes V profiles to recover the fields in the MHD cube both at original resolution and after degrading with a point spread function. In both these cases, we aim to empirically represent the field strengths returned by the MLR method in terms of the field strengths in the MHD cube. Results: We have identified two new line pairs that are very well adapted to be used for MLR measurements. The first pair is in the visible, Fe I 6820-6842 Å, whose intensity profiles have previously been used to measure stellar magnetic fields, and the other pair is in the infrared (IR), Fe I 15 534-15 542 Å. The lines in these pairs reproduce the magnetic fields in the MHD cube rather well and, in fact, somewhat better than the original 5250 Å pair. Conclusions: The newly identified line pairs complement the old pairs. The lines in the new IR pair, because of their higher Zeeman sensitivity, are ideal for the measurement of weak fields. The new visible pair works best above 300 G. The new IR pair, due to its large Stokes V signal samples more fields in the MHD cube than the old IR pair at 1.56 μm, even in the presence of noise, and hence likely also on the real Sun. Owing to their low formation heights (100-200 km above τ5000 = 1), both the new line pairs are well suited for probing magnetic fields in the lower photosphere.

  16. An Investigation of Induced Voltages to an Underground Gas Pipeline from an Overhead Transmission Line

    Science.gov (United States)

    Isogai, Hiroshi; Ametani, Akihiro; Hosokawa, Yuji

    This paper has investigated induced voltages characteristics from an overhead transmission line to a buried gas pipeline by applying a modeling method of the induced voltages proposed by the authors. EMTP simulation results agree with analytical results obtained from a well-known formula. The induced voltages are significantly dependent on the configuration of an overhead line. A horizontal line induces the largest voltage to the gas pipeline, and an induced voltage by a vertical twin-circuit line is smaller by about 20% than that by a vertical single-circuit line.

  17. About the Coupling Factor Influence on the Ground Fault Current Distribution on Overhead Transmission Lines

    Directory of Open Access Journals (Sweden)

    VINTAN, M.

    2010-05-01

    Full Text Available A phase-to-ground fault occurring on a transmission line divides the line into two sections, each extending from the fault towards one end of the line. These two sections of the line may be considered infinite if some certain conditions are met; otherwise, they must be regarded as finite. This paper treats the case when those two sections of the line are both very long and allows the determination of the ground fault current distribution in power networks. The influence of the coupling factor between the faulted phase and the ground wire on the ground fault current distribution is studied.

  18. An optimal design method for improving the lightning performance of overhead high voltage transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Ekonomou, L.; Iracleous, D.P.; Gonos, I.F.; Stathopulos, I.A. [National Technical University of Athens, School of Electrical and Computer Engineering, High Voltage Laboratory, 9 Iroon Politechniou St., Zografou, GR 157 80 Athens (Greece)

    2006-04-15

    This paper presents a method for the optimal design of high voltage transmission lines taking into consideration shielding and backflashover failure rates. The minimization of suitably defined performance indices, which relate the failures caused by lightning in a transmission line to both line insulation level and tower footing resistance, is aimed. Optimum values for both line insulation level and tower footing resistance are calculated. The method is applied on several operating Hellenic transmission lines of 150 and 400kV, respectively, carefully selected among others, due to their high failure rates during lightning thunderstorms. Special attention has been paid on open loop lines, where a possible failure could bring the system out of service causing significant problems. The obtained design parameters, which reduce the failure rates caused by lightning, are compared with the existing design parameters of the transmission lines leading up to useful conclusions. The proposed optimization method can be proved a valuable tool to the studies of electric power systems designers, intending to reduce the failure rates caused by lightning. (author)

  19. TRANSMISSION LINE-WIRE DANCING (GALLOPING – LYAPUNOV INSTABILITY

    Directory of Open Access Journals (Sweden)

    V. I. Vanko

    2014-01-01

    Full Text Available This article describes aerodynamic losses of damping, or aerodynamic instability, which we observe in experiments and in engineering practice. As applied to industrial high-voltage lines this phenomenon is usually called galloping (dancing of phase line wires. This phenolmenon can be explained by Lyapunov’s instability of equilibrium state of wires profile (cross-section. In addition to known condition of Grauert-den-Hartog’s instability there was obtained practical condition of instability, which depends only on stationary aerodynamic profile’s factor – dimensionless coefficient of head resistance and lift coefficient, and also on their derivative with respect to the angle of attack.There was suggested an effective numerical-analytical method of investigation of stability for equilibrium of profile’s state in flow, which was developed at the department “Applied mathematics” of Bauman MSTU. This method allows to determine the stationary aerodynamics characteristics of profile by numerical simulation of profile flow under different angles of attack by vortex element method and later on the application of analytical conditions of stability and Lyapunov’s instability of equilibrium positions. The obtained results during the investigation of rhombic and square profiles stability, as well as general profile of iced wire, and their comparisons with the known experiments’ results in aerodynamic tubes indicate the precision of developed methods and algorithms. The usage of mesh-free Lagrange method of vortex elements and software for their realization allows to solve also dual problems of aerohydroelasticity and to carry out direct numerical simulation of profile movement in flow. In this article the investigations’ results of different authors in this field were taken into account.

  20. Marys Lake 69/115-kV transmission line upgrade and substation expansion projects

    International Nuclear Information System (INIS)

    1996-05-01

    Western Area Power Administration (Western) and the Platte River Power Authority (Platte River) propose to upgrade portions of the existing electric transmission and substation system that serves the Town of Estes Park, Colorado. The existing transmission lines between the Estes Power Plant Switchyard and the Marys Lake Substation include a 115,000 volt (115-kV) line and 69,000 volt (69-kV) line. Approximately one mile is a double-circuit 115/69-kV line on steel lattice structures, and approximately two miles consists of separate single-circuit 115-kV and a 69-kV lines, constructed on wood H-Frame structures. Both lines were constructed in 1951 by the US Bureau of Reclamation. The existing transmission lines are on rights-of-way (ROW) that vary from 75 feet to 120 feet and are owned by Western. There are 48 landowners adjacent to the existing ROW. All of the houses were built adjacent to the existing ROW after the transmission lines were constructed. Upgrading the existing 69-kV transmission line between the Marys Lake Substation and the Estes Power Plant Switchyard to 115-kV and expanding the Marys Lake Substation was identified as the most effective way in which to improve electric service to Estes Park. The primary purpose and need of the proposed project is to improve the reliability of electric service to the Town of Estes Park. Lack of reliability has been a historical concern, and reliability will always be less than desired until physical improvements are made to the electrical facilities serving Estes Park

  1. Marys Lake 69/115-kV transmission line upgrade and substation expansion projects

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-01

    Western Area Power Administration (Western) and the Platte River Power Authority (Platte River) propose to upgrade portions of the existing electric transmission and substation system that serves the Town of Estes Park, Colorado. The existing transmission lines between the Estes Power Plant Switchyard and the Marys Lake Substation include a 115,000 volt (115-kV) line and 69,000 volt (69-kV) line. Approximately one mile is a double-circuit 115/69-kV line on steel lattice structures, and approximately two miles consists of separate single-circuit 115-kV and a 69-kV lines, constructed on wood H-Frame structures. Both lines were constructed in 1951 by the US Bureau of Reclamation. The existing transmission lines are on rights-of-way (ROW) that vary from 75 feet to 120 feet and are owned by Western. There are 48 landowners adjacent to the existing ROW. All of the houses were built adjacent to the existing ROW after the transmission lines were constructed. Upgrading the existing 69-kV transmission line between the Marys Lake Substation and the Estes Power Plant Switchyard to 115-kV and expanding the Marys Lake Substation was identified as the most effective way in which to improve electric service to Estes Park. The primary purpose and need of the proposed project is to improve the reliability of electric service to the Town of Estes Park. Lack of reliability has been a historical concern, and reliability will always be less than desired until physical improvements are made to the electrical facilities serving Estes Park.

  2. Bipole III transmission line Henday-Riel: Alternative corridors status report

    International Nuclear Information System (INIS)

    1991-01-01

    As part of expansion plans in the Manitoba Hydro system, it is proposed to build a 850-km high voltage dc transmission line from the Henday converter station on the Nelson River to a new converter station near Winnipeg. A review is provided of work done on the first stage of route selection and environmental assessment for this project. Right-of-way requirements are outlined and environmental impact issues are discussed in the areas of employment and business opportunities, effects on wilderness areas and aesthetics, electric and magnetic field effects, and land use. The four zones, east and west of Lake Winnipeg, that were studied in the selection of potential corridors are described along with the corridor siting criteria. Five discrete corridor alternatives are identified and evaluated. A route east of Lake Winnipeg has been selected as the preferred corridor. Feedback from public consultations will assist in preparation of a final corridor selection study which is to be submitted to federal and provincial environmental review. 12 figs

  3. Tracing overhead transmission line corridors with regard to environmental and spatial qualities

    Directory of Open Access Journals (Sweden)

    Alenka Cof

    2005-01-01

    Full Text Available The article deals with possibilities for running the proposed overhead transmission line Okroglo-Italian border. The Slovene and Italian methods are shown as methods enabling consideration of environmental and spatial impact within the process of planning overhead transmission line corridors. The Slovene method consists of analyses of attractiveness and vulnerability, whereby the first considers those functional and economic factors that affect spatial attractiveness for overhead transmission lines. Thus we can assess the level of economic and functional suitability of alternative routes of the proposed 400 kilovolt overhead transmission line from transformation station Okroglo (Slovenia to Srednje, Golo Brdo and Vrtojba, three potential contact points on the Slovene–Italian border. In accordance with stipulations of the Law on spatial management vulnerability models were prepared, which were used to simulate the development’s potential negative environmental effects and to analyse suitability, which implies harmonisation of development and protection demands. Their result is a possible corridor that can be developed without significant conflicts. The Italian procedure was developed to trace the transmission line corridor from the Slovenian border to the transformation station in Udine. It was also applied on the Slovenian side. Three groups of factors were considered in the procedure: exclusion, repulsion, and attraction. The much simpler procedure enables comparisons, since it uses the same or at least similar spatial data. In conclusion a short commentary is added about the corridor concept as a planning tool.

  4. Pressure control of a pneumatic control system with a long transmission line

    International Nuclear Information System (INIS)

    Jang, Ji Seong; Lee, Kwang Kuk; Choi, Myung Soo

    2003-01-01

    In this study, a robust controller to control pressure in a pneumatic pressure vessel with a long transmission line is proposed. Frequency response of transmission line using compressible fluid is changed by the flowing state of the fluid. So, if a fixed gain controller designed based on a model supposed the flowing state to a specific state, the performance of the control system could be degraded because of the modelling error. The controller designed in this study is composed of two parts. One is a feedback controller to improve a feedback characteristics and to compensate the influence of the variation of transfer characteristics of a transmission line owing to the change of flowing state and the other is a feed forward controller to regulate command following performance. The experimental results with the designed controller show that the robustness of the control system is achieved regardless of the change of the model of the transmission line. Therefore, the designed controller can be utilized for the performance improvement of a pressure control system with a long transmission line using compressible fluid

  5. Electromagnetic Field Interference on Transmission Lines due to On-Board Antenna

    Directory of Open Access Journals (Sweden)

    Heekwon Lee

    2015-01-01

    Full Text Available As the available space in the board of a mobile device becomes smaller and more compact, circuit elements and transmission lines are arranged in very close proximity, especially from the antennas which are usually installed on the same board. Due to the various on-board antennas which are designed in small space, the transmission lines on the board are electromagnetically interfered, resulting in the performance degradation of the circuit. So the engineers and circuit designers should find the least interfered place for the transmission lines and components to minimize the electromagnetic interferences. This paper discusses and presents a methodology to find the least sensitive position in the induced current distribution as well as in the noise power delivered from the antenna. For this purpose some vertical, horizontal, and bent transmission lines with antenna on the same board are designed and fabricated with and without common ground, and the transferred powers to the transmission lines were measured and were also simulated using a full-wave simulator. The results predicted by the EM simulation model were successfully confirmed through the measurement of S-parameters in the experimental setup, which shows the validness of the suggested analysis method.

  6. Research on Poppers Used as Electrical Connectors in High Speed Textile Transmission Lines

    Directory of Open Access Journals (Sweden)

    Leśnikowski Jacek

    2016-12-01

    Full Text Available This paper presents results of research on poppers used as electrical connectors connecting fragments of textile signal lines. These lines can be used in intelligent clothing for connecting electronic modules implemented in it. Intelligent (smart clothing can be used, among others, in the health monitoring of the elderly, newborn babies, or people working in hazardous conditions, for example, firefighters and soldiers. The aim of the present study was to examine the usefulness of poppers, widely used in clothing, as electrical connectors connecting parts of the textile signal lines designed for transmission of high-speed digital signals. The paper presents examples of measured parameters characterizing transmission properties of two fragments of the coplanar, textile transmission line connected to each other using conventional poppers. The presented measurement results contain the so-called s parameters, characteristic impedance of the poppers, and eye measurements characterizing distortions of digital signals passing through the tested line. In the article, the effect of temperature and humidity of air surrounding the tested poppers on their characteristic impedance was also presented. This property and its stability are important in signal lines designed for high-speed data transmission.

  7. Soliton solutions and conservation laws for lossy nonlinear transmission line equation

    Science.gov (United States)

    Tchier, Fairouz; Yusuf, Abdullahi; Aliyu, Aliyu Isa; Inc, Mustafa

    2017-07-01

    In this article, the Lie symmetry and Ricatti-Bernoulli (RB) sub-ODE method are applied to obtain soliton solutions for nonlinear transmission line equation (NLTLs). The NLTLs is defined to be a structure whereby a short-duration pulses known as electrical solitons can be invented and disseminated. We compute conservation laws (Cls) via a non-linear self-adjointness approach. A suitable substitution for NLTLs is found and the obtained substitution makes the NLTLs equation a non-linearly self-adjoint. We establish Cls for NLTLs equation by the new Cls theorem presented by Ibragimov. We obtain trigonometric, algebraic and soliton solutions. The obtained solutions can be useful for describing the concentrations of transmission lines problems, for NLTLs. The parameters of the transmission line play a significant role in managing the original form of the soliton.

  8. High voltage transmission lines studies with the use of artificial intelligence

    Energy Technology Data Exchange (ETDEWEB)

    Ekonomou, L. [A.S.PE.T.E. - School of Pedagogical and Technological Education, Department of Electrical Engineering Educators, N. Heraklion, 141 21 Athens (Greece)

    2009-12-15

    The paper presents an alternative approach for the studies of high voltage transmission lines based on artificial intelligence and more specifically artificial neural networks (ANNs). In contrast to the existing conventional-analytical techniques and simulations which are using in the calculations empirical and/or approximating equations, this approach is based only on actual field data and actual measurements. The proposed approach is applied on high voltage transmission lines in order to calculate the lightning outages, on grounding systems in order to assess the grounding resistance and on high voltage transmission lines' polluted insulators in order to estimate the critical flashover voltage. The obtained results are very close to the actual ones for all three case studies, something which clearly implies that the ANN approach is well working and has an acceptable accuracy, constituting an additional tool of electric engineers. (author)

  9. A new shielding effectiveness measurement method based on a skin-effect transmission line coupler

    Directory of Open Access Journals (Sweden)

    T. Kleine-Ostmann

    2007-06-01

    Full Text Available We propose a new convenient material shielding effectiveness measurement method based on a skin-effect transmission line coupler. The method is somewhat similar to the arrangement with two coupled TEM cells known from literature. The transmission line coupler consists of a pair of identical transmission line 2-port devices. Each device contains a coaxial waveguide, with a circular inner conductor and an outer conductor having a square cross section. One side of the outer conductor is left completely open as a slot. The slot is surrounded by a large metal housing to contact the two halves. As a measure for the shielding effectiveness the coupling between the two devices is measured in terms of scattering parameters after the test material is brought between the two halves. The devices can be used in a range from low frequencies to a few GHz.

  10. Non-Linear Transmission Line (NLTL) Microwave Source Lecture Notes the United States Particle Accelerator School

    Energy Technology Data Exchange (ETDEWEB)

    Russell, Steven J. [Los Alamos National Laboratory; Carlsten, Bruce E. [Los Alamos National Laboratory

    2012-06-26

    We will quickly go through the history of the non-linear transmission lines (NLTLs). We will describe how they work, how they are modeled and how they are designed. Note that the field of high power, NLTL microwave sources is still under development, so this is just a snap shot of their current state. Topics discussed are: (1) Introduction to solitons and the KdV equation; (2) The lumped element non-linear transmission line; (3) Solution of the KdV equation; (4) Non-linear transmission lines at microwave frequencies; (5) Numerical methods for NLTL analysis; (6) Unipolar versus bipolar input; (7) High power NLTL pioneers; (8) Resistive versus reactive load; (9) Non-lineaer dielectrics; and (10) Effect of losses.

  11. Transmission Line Jobs and Economic Development Impact (JEDI) Model User Reference Guide

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, M.; Keyser, D.

    2013-10-01

    The Jobs and Economic Development Impact (JEDI) models, developed through the National Renewable Energy Laboratory (NREL), are freely available, user-friendly tools that estimate the potential economic impacts of constructing and operating power generation projects for a range of conventional and renewable energy technologies. The Transmission Line JEDI model can be used to field questions about the economic impacts of transmission lines in a given state, region, or local community. This Transmission Line JEDI User Reference Guide was developed to provide basic instruction on operating the model and understanding the results. This guide also provides information on the model's underlying methodology, as well as the parameters and references used to develop the cost data contained in the model.

  12. Fault Location and Classification for Transmission Line Based on Wavelet Transform

    OpenAIRE

    Wang, Qiuhong

    2016-01-01

    With the rapid development of power systems, locating and classifying faults is critical to the continuity and reliability of the transmission system. In this thesis, a traveling-wave based technique for fault location and classification on high voltage and extremely high-voltage transmission lines is proposed. The traveling-wave based protection has the advantage of fast response and not being affected by power swing and CTs saturation. In this thesis, the transient characteristics of single...

  13. Magnetic field line diffusion at the onset of stochasticity

    International Nuclear Information System (INIS)

    Elsaesser, K.; Deeskow, P.

    1987-01-01

    The Hamiltonian equations of a particle in a random set of waves just above the stochasticity threshold are considered both theoretically and numerically. First we derive the diffusion coefficient and the autocorrelation time perturbatively without using the thermodynamic limit, and we discuss the relevance of the Hamiltonian problem for particle acceleration and magnetic field line flow. Then we integrate the equations for an ensemble of magnetic field lines numerically for a model problem and show the time evolution of moments and correlations. Twice above the threshold we observe diffusive behaviour from the beginning, but the diffusion coefficient includes also the non-resonant modes. Just at threshold we find first a short phase of free acceleration, later a diffusion which is lower than predicted by the theoretical formula. The best way to analyze the problem is in terms of cumulants, but a reliable comparison with any theory requires also a time integration of the corresponding kinetic equations. (orig.)

  14. Simple Correctors for Elimination of High-Order Modes in Corrugated Waveguide Transmission Lines.

    Science.gov (United States)

    Kowalski, Elizabeth J; Shapiro, Michael A; Temkin, Richard J

    2014-01-01

    When using overmoded corrugated waveguide transmission lines for high power applications, it is necessary to control the mode content of the system. Ideally, overmoded corrugated transmission lines operate in the fundamental HE 11 mode and provide low losses for long distances. Unwanted higher order modes (HOMs), particularly LP 11 and HE 12 , are often excited in the experimental systems due to practical misalignments in the transmission line system. This paper discusses how the unwanted modes propagate along with the fundamental mode in the transmission line system by formulating an equation that relates the center of power offset and angle of propagation of a beam (for the HE 11 and LP 11 modes) or the waist size and phase front radius of curvature of a beam (for the HE 11 and HE 12 modes). By introducing two miter bend correctors into the transmission system-miter bends that have slightly angled or ellipsoidal mirrors-the HOMs can be precisely manipulated in the system. This technique can be used to eliminate small quantities of unwanted modes, thereby creating a nearly pure fundamental mode beam with minimal losses. Examples of these applications are calculated and show the theoretical conversion of up to 10% HOM content into the fundamental HE 11 mode with minimal losses.

  15. Circuit simulation of exponential transmission line for petawatt Z-pinch plasma drivers

    International Nuclear Information System (INIS)

    Zeng Zhengzhong

    2011-01-01

    It was demonstrated, based on the PSPICE circuit simulation, that the sectioning number for the circuit simulation of an exponential transmission line should be determined as twice the line's one-way electromagnetic wave transport time(electric length) divided by the wave-front of input pulse, owing to elimination of the wave reflections caused by artificial impedance discontinuity in the line's circuit simulation model, which employs a serial and sectional transmission line with impedances constant in each section but stair-step-varied between sections, and with total electric length the same as that of the exponential line under simulation. A pulse of 112.2 ns wave-front propagates through an exponential water transmission line of 1 234.2 ns one-way transport time will give the best sectioning number of 22, when the constant impedance of each section is given by the geometric mean of the two ends' impedances of the corresponding section on the exponential line under simulation. This sectioning rule is equivalent to the statement that the two-way transport time of each section should be equal to the input pulse's wave-front. (authors)

  16. Fractional analysis for nonlinear electrical transmission line and nonlinear Schroedinger equations with incomplete sub-equation

    Science.gov (United States)

    Fendzi-Donfack, Emmanuel; Nguenang, Jean Pierre; Nana, Laurent

    2018-02-01

    We use the fractional complex transform with the modified Riemann-Liouville derivative operator to establish the exact and generalized solutions of two fractional partial differential equations. We determine the solutions of fractional nonlinear electrical transmission lines (NETL) and the perturbed nonlinear Schroedinger (NLS) equation with the Kerr law nonlinearity term. The solutions are obtained for the parameters in the range (0operator and we found the traditional solutions for the limiting case of α =1. We show that according to the modified Riemann-Liouville derivative, the solutions found can describe physical systems with memory effect, transient effects in electrical systems and nonlinear transmission lines, and other systems such as optical fiber.

  17. Schoen manifold with line bundles as resolved magnetized orbifolds

    Energy Technology Data Exchange (ETDEWEB)

    Groot Nibbelink, Stefan [Muenchen Univ. (Germany). Arnold Sommerfeld Center for Theoretical Physics; Vaudrevange, Patrick K.S. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2012-12-15

    We give an alternative description of the Schoen manifold as the blow-up of a Z{sub 2} x Z{sub 2} orbifold in which one Z{sub 2} factor acts as a roto-translation. Since for this orbifold the fixed tori are only identified in pairs but not orbifolded, four-dimensional chirality can never be obtained using standard techniques alone. However, chirality is recovered when its tori become magnetized. To exemplify this, we construct an SU(5) GUT on the Schoen manifold with Abelian gauge fluxes, which becomes an MSSM with three generations after an appropriate Wilson line is associated to its freely acting involution. We reproduce this model as a standard orbifold CFT of the (partially) blown down Schoen manifold with a magnetic flux. Finally, in analogy to a proposal for non-perturbative heterotic models by Aldazabal et al. we suggest modifications to the heterotic orbifold spectrum formulae in the presence of magnetized tori.

  18. The Bending Magnets for the Proton Transfer Line of CNGS

    CERN Document Server

    Schirm, K M; Anashin, V; Kiselev, O; Maraev, V; Ogurtsov, A; Pupkov, Yu; Ruvinsky, E; Zhilyaev, K; Konstantinov, Yu S; Kosjakin, M; Peregud, V

    2006-01-01

    The project "CERN neutrinos to Gran Sasso (CNGS)", a collaboration between CERN and the INFN (Gran Sasso Laboratory) in Italy, will study neutrino oscillations in a long base-line experiment. High-energy protons will be extracted from the CERN SPS accelerator, transported through a 727 m long transfer line and focused onto a graphite target to produce a beam of pions and kaons and subsequently neutrinos. The transfer line requires a total of 78 dipole magnets. They were produced in the framework of an in-kind contribution of Germany via DESY to the CNGS project. The normal conducting dipoles, built from laminated steel cores and copper coils, have a core length of 6.3 m, a 37 mm gap height and a nominal field range of 1.38 T - 1.91 T at a maximum current of 4950 A. The magnet design was a collaboration between CERN and BINP. The half-core production was subcontracted to EFREMOV Institute; the coil fabrication, magnet assembly and the field measurements were concluded at BINP in June 2004. The main design issu...

  19. The bending magnets for the LHC injection transfer lines

    CERN Document Server

    Anashin, V; Labutsky, S A; Mejidzade, V; Mikhailov, S; Pupkov, Yu A; Rouvinsky, E; Sukhina, B; Kalbreier, Willi; Kouba, G; Schirm, K M; Weisse, E; Konstantinov, Yu S; Kosjakin, M; Peregud, V

    2002-01-01

    Two injection transfer lines, each about 2.8 km long, with 51 and 107 degree horizontal deflection, are being built to transfer protons at 450 GeV from the Super Proton Synchrotron (SPS) to the Large Hadron Collider (LHC). A total of 360 dipole magnets are required; they have been produced in the framework of the contribution of the Russian Federation to the construction of the LHC. The classical dipoles, built from laminated steel cores and copper coils, have a core length of 6.3 m, 25 mm gap height and a nominal field of 1.81 T at a current of 5270 A. The magnet design was made in collaboration between CERN and BINP. An unusual design has been chosen for the coils to cope with the limited voltage from the available power supplies. All magnets in each of the two lines will be powered in series. The coil is composed of overlapping, but electrically insulated, half coils of 3 1/2 turns each. Thus, the power connections for IN and OUT are placed on opposite magnet ends. Short copper braids are used to connect a...

  20. Studies on the transmission of sub-THz waves in magnetized inhomogeneous plasma sheath

    Science.gov (United States)

    Yuan, Kai; Shen, Linfang; Yao, Ming; Deng, Xiaohua; Chen, Zhou; Hong, Lujun

    2018-01-01

    There have been many studies on the sub-terahertz (sub-THz) wave transmission in reentry plasma sheaths. However, only some of them have paid attention to the transmission of sub-THz waves in magnetized plasma sheaths. In this paper, the transmission of sub-THz waves in both unmagnetized and magnetized reentry plasma sheaths was investigated. The impacts of temporal evolution of the plasma sheath on the wave transmission were studied. The transmission of "atmospheric window" frequencies in a magnetized plasma sheath was discussed in detail. According to the study, the power transmission rates (Tp) for the left hand circular (LHC) and the right hand circular modes in the magnetized plasma sheath are obviously higher and lower than those in the unmagnetized plasma sheath, respectively. The Tp of LHC mode increases with both wave frequency and external magnetic field strength. Also, the Tp of LHC mode in both magnetized and unmagnetized plasma sheaths varies with time due to the temporal evolution of the plasma sheath. Moreover, the performance of sub-THz waves in magnetized plasma sheath hints at a new approach to the "blackout" problem. The new approach, which is in the capability of modern technology, is to utilize the communication system operating at 140 GHz with an onboard magnet installed near the antenna.

  1. Ground-Wave Propagation Effects on Transmission Lines through Error Images

    Directory of Open Access Journals (Sweden)

    Uribe-Campos Felipe Alejandro

    2014-07-01

    Full Text Available Electromagnetic transient calculation of overhead transmission lines is strongly influenced by the natural resistivity of the ground. This varies from 1-10K (Ω·m depending on several media factors and on the physical composition of the ground. The accuracy on the calculation of a system transient response depends in part in the ground return model, which should consider the line geometry, the electrical resistivity and the frequency dependence of the power source. Up to date, there are only a few reports on the specialized literature about analyzing the effects produced by the presence of an imperfectly conducting ground of transmission lines in a transient state. A broad range analysis of three of the most often used ground-return models for calculating electromagnetic transients of overhead transmission lines is performed in this paper. The behavior of modal propagation in ground is analyzed here into effects of first and second order. Finally, a numerical tool based on relative error images is proposed in this paper as an aid for the analyst engineer to estimate the incurred error by using approximate ground-return models when calculating transients of overhead transmission lines.

  2. New formulae for magnetic relative helicity and field line helicity

    Science.gov (United States)

    Aly, Jean-Jacques

    2018-01-01

    We consider a magnetic field {B} occupying the simply connected domain D and having all its field lines tied to the boundary S of D. We assume here that {B} has a simple topology, i.e., the mapping {M} from positive to negative polarity areas of S associating to each other the two footpoints of any magnetic line, is continuous. We first present new formulae for the helicity H of {B} relative to a reference field {{B}}r having the same normal component {B}n on S, and for its field line helicity h relative to a reference vector potential {{C}}r of {{B}}r. These formulae make immediately apparent the well known invariance of these quantities under all the ideal MHD deformations that preserve the positions of the footpoints on S. They express indeed h and H either in terms of {M} and {B}n, or in terms of the values on S of a pair of Euler potentials of {B}. We next show that, for a specific choice of {{C}}r, the field line helicity h of {B} fully characterizes the magnetic mapping {M} and then the topology of the lines. Finally, we give a formula that describes the rate of change of h in a situation where the plasma moves on the perfectly conducting boundary S without changing {B}n and/or non-ideal processes, described by an unspecified term {N} in Ohm’s law, are at work in some parts of D.

  3. Weld-Windsor 115-kV Transmission Line Project, Weld County, Colorado

    International Nuclear Information System (INIS)

    1996-05-01

    The Western Area Power Administration is proposing to rebuild a 3.0 mile segment of the existing Flatiron-Weld 115-kV transmission line in Weld County. The line would be reconductored with new conductor on new wood pole double circuit structures. The new structures would support a double circuit transmission line configuration. The first circuit would be owned by Western and the second by Public Service Company of Colorado (PSCO). Alternatives considered included no action, constructing PSCO's circuit on new right-of-way, and reconductoring Western's existing line on the same structures. The proposed action was selected because it provided an opportunity to share structures with PSCO and, overall, would minimize costs and environmental impacts. The environmental assessment identifies minor effects on existing natural or human resources and minor benefits for agricultural operations

  4. Ballistic charge carrier transmission through graphene multi-barrier structures in uniform magnetic field

    International Nuclear Information System (INIS)

    Zubarev, A; Dragoman, D

    2014-01-01

    We investigate charge carrier transport in graphene multi-barrier structures placed in a uniform magnetic field. The transmission coefficient is found analytically by generalizing the transfer matrix method for the case of graphene regions subjected to a uniform magnetic field. The transmission coefficient through the structure can be modulated by varying the gate voltages, the magnetic field and/or the width of the gated regions. Such a configuration could be used in multiple-valued logic circuits, since it has several output states with discrete and easily selectable transmission/current values. (paper)

  5. CHARACTERISTICS OF POWER SELF-COMPENSATED TRANSMISSION LINES EXTREMELY COMPACT 330-350 kV

    Directory of Open Access Journals (Sweden)

    Postolaty V.M.

    2013-12-01

    Full Text Available The optimal configuration of phases placement of double circuit compact controlled self-compensated high-voltage power lines (KUSVL with the voltage of 330-500 kV at the condition of achieving of the maximum admissible value of the electric field tension on the surface of split phase at a given design was determined. The parameters of these lines at the extreme values of the angular shift (θ between the circuits’ systems voltages were calculated. It was shown, that the surge impedance of KUSVL without special phase-shifting transformers (e.g. θ = 0˚ is minimal, and is equal (for each phase for the option of 330 kV and wires 3AS-300/39 - 196 ohms, and for voltage of 500 kV and phase conductors 6AS-240/39 –162 ohms. The magnitude of transmission capacity of considered line (for both circuits at rated voltage is maximal and equal to 1118 MW (for 330 kV line and 3080 MW (for 500 kV line. At changing of line to the mode of angle θ = 180˚ (with special phase-shifting transformer surge impedance is maximal and the transmission capacity minimal. Ratio of the maximal value of transmission capacity to the minimal (regulation range reaches values of up to 1.5.

  6. Magnetic fields of weak line T-Tauri stars

    Science.gov (United States)

    Hill, Colin A.; MaTYSSE Collaboration

    2017-10-01

    T-Tauri stars (TTS) are late-type pre-main-sequence (PMS) stars that are gravitationally contracting towards the MS. Those that possess a massive accretion disc are known as classical T-Tauri stars (cTTSs), and those that have exhausted the gas in their inner discs are known as weak-line T-Tauri stars (wTTSs). Magnetic fields largely dictate the angular momentum evolution of TTS and can affect the formation and migration of planets. Thus, characterizing their magnetic fields is critical for testing and developing stellar dynamo models, and trialling scenarios currently invoked to explain low-mass star and planet formation. The MaTYSSE programme (Magnetic Topologies of Young Stars and the Survival of close-in Exoplanets) aims to determine the magnetic topologies of ~30 wTTSs and monitor the long-term topology variability of ~5 cTTSs. We present several wTTSs that have been magnetically mapped thus far (using Zeeman Doppler Imaging), where we find a much wider range of field topologies compared to cTTSs and MS dwarfs with similar internal structures.

  7. Canby Area Service Project : Substation and Associated Transmission Line : Environmental Assessment.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1992-02-01

    Bonneville Power Administration (BPA) provides power to Surprise Valley Electrification Corporation (SVEC) in Modoc County, California. BPA uses PacificCorp's substation and transmission facilities between Alturas and Canby, California to transfer power to SVEC's Canby Substation. In the next year, SVEC expects increased industrial, agricultural, and residential electric loads on their 69-kV transmission system south of Canby. SVEC's substation can accommodate only about 10 percent of the expected additional electric load. BPA's proposed action is intended to meet SVEC's increasing electric load. BPA proposes to meet SVEC's increasing energy load by tapping into BPA's existing BPA Malin-Warner 230-kV transmission line, and building an 7.9-mile transmission line to a new BPA substation. BPA proposes to build the new substation next to the west side of SVEC's Canby Substation (Figure 1). This new substation will allow SVEC to move the additional power over their existing transmission or distribution lines. This report is the environmental assessment of the potential impact of the proposed project. The assessment determined that no environmental impact statement'' is not required.

  8. Canby Area Service Project substation and associated transmission line. Environmental Assessment

    Energy Technology Data Exchange (ETDEWEB)

    1992-02-01

    Bonneville Power Administration (BPA) provides power to Surprise Valley Electrification Corporation (SVEC) in Modoc County, California. BPA uses PacificCorp`s substation and transmission facilities between Alturas and Canby, California to transfer power to SVEC`s Canby Substation. In the next year, SVEC expects increased industrial, agricultural, and residential electric loads on their 69-kV transmission system south of Canby. SVEC`s substation can accommodate only about 10 percent of the expected additional electric load. BPA`s proposed action is intended to meet SVEC`s increasing electric load. BPA proposes to meet SVEC`s increasing energy load by tapping into BPA`s existing BPA Malin-Warner 230-kV transmission line, and building an 7.9-mile transmission line to a new BPA substation. BPA proposes to build the new substation next to the west side of SVEC`s Canby Substation (Figure 1). This new substation will allow SVEC to move the additional power over their existing transmission or distribution lines. This report is the environmental assessment of the potential impact of the proposed project. The assessment determined that no ``environmental impact statement`` is not required.

  9. Transmission Line Ampacity Improvements of AltaLink Wind Plant Overhead Tie-Lines Using Weather-Based Dynamic Line Rating

    Energy Technology Data Exchange (ETDEWEB)

    Bhattarai, Bishnu P.; Gentle, Jake P.; Hill, Porter; McJunkin, Tim; Myers, Kurt S.; Abbound, Alex; Renwick, Rodger; Hengst, David

    2017-07-01

    Abstract—Overhead transmission lines (TLs) are conventionally given seasonal ratings based on conservative environmental assumptions. Such an approach often results in underutilization of the line ampacity as the worst conditions prevail only for a short period over a year/season. We presents dynamic line rating (DLR) as an enabling smart grid technology that adaptively computes ratings of TLs based on local weather conditions to utilize additional headroom of existing lines. In particular, general line ampacity state solver utilizes measured weather data for computing the real-time thermal rating of the TLs. The performance of the presented method is demonstrated from a field study of DLR technology implementation on four TL segments at AltaLink, Canada. The performance is evaluated and quantified by comparing the existing static and proposed dynamic line ratings, and the potential benefits of DLR for enhanced transmission assets utilization. For the given line segments, the proposed DLR results in real-time ratings above the seasonal static ratings for most of the time; up to 95.1% of the time, with a mean increase of 72% over static rating.

  10. Analysis of risk assessment algorithm from power supply interruption due to transmission line fault

    Directory of Open Access Journals (Sweden)

    Andrukhova Alina

    2017-01-01

    Full Text Available The guaranteed reliable and uninterrupted supply of electrical energy to consumers is an important task. It can be noted that currently there is no well-structured system for ensuring reliability or security and preventing risk occurrence. In this report, risk assessment algorithms in case of accidents on transmission line are developed and tested by means of the analytical example.

  11. Evaluation of Transmission Line Model Structures for Silicide-to-Silicon Specific Contact Resistance Extraction

    NARCIS (Netherlands)

    Stavitski, N.; van Dal, Mark J.H.; Lauwers, Anne; Vrancken, Christa; Kovalgin, Alexeij Y.; Wolters, Robertus A.M.

    2008-01-01

    In order to measure silicide-to-silicon specific contact resistance �?c, transmission line model (TLM) structures were proposed as attractive candidates for embedding in CMOS processes. We optimized TLM structures for nickel silicide and platinum silicide and evaluated them for various doping levels

  12. Measurements and Calculations of CW Transmission Lines for ICRF in W7-X

    Science.gov (United States)

    Birus, D.; Hartmann, D. A.; Becker, W.

    2005-09-01

    Continuous wave capable transmission line components for use in the ion cyclotron range of frequencies are required for forthcoming high power fusion experiments like Wendelstein 7-X and ITER. For example, ITER requires 30 Ω transmission line components for transmitting 2.5 MW at a VSWR of 1.5. This corresponds to maximum voltages and currents of about 12 kVrms and 360 Arms, respectively. Since commercially available transmission lines do not meet these requirements, a 9″ coaxial transmission line resonator was built with a resonance frequency of 60 MHz and a length of 5 m, pressurized with dry air at 3 Bar. Since its quality factor is about 2500 the ITER requirements can be locally obtained using an available 50 kW CW RF source. This setup was used to test the suitability of electrical spring contacts and ceramic spacers made of AlN and Al2O3. The temperature increase in the ceramics was found to be in good agreement with calculations based on measured values of tan δ and ɛ. In a modified resonator with a total length of 7.5 m, water cooled outer conductor but no cooling of the inner conductor it was found that heat transport from the inner to the outer conductor via convection and radiation was sufficient to keep the temperature of the inner conductor at the current maximum below 120°C.

  13. Measuring the complex permittivity tensor of uniaxial biological materials with coplanar waveguide transmission line

    Science.gov (United States)

    A simple and accurate technique is described for measuring the uniaxial permittivity tensor of biological materials with a coplanar waveguide transmission-line configuration. Permittivity tensor results are presented for several chicken and beef fresh meat samples at 2.45 GHz....

  14. An ultrasonic guided wave approach for the inspection of overhead transmission line cables

    DEFF Research Database (Denmark)

    Yücel, Mehmet K.; Legg, Mathew; Kappatos, Vasileios

    2017-01-01

    Inspection of overhead transmission line cables is performed using various non-destructive testing techniques, such as visual, temperature, and eddy current-based inspection; yet each of these techniques have their respective shortcomings and safety concerns. The use of ultrasonic guided waves...

  15. Lightning Protection Performance Assessment of Transmission Line Based on ATP model Automatic Generation

    Directory of Open Access Journals (Sweden)

    Luo Hanwu

    2016-01-01

    Full Text Available This paper presents a novel method to solve the initial lightning breakdown current by combing ATP and MATLAB simulation software effectively, with the aims to evaluate the lightning protection performance of transmission line. Firstly, the executable ATP simulation model is generated automatically according to the required information such as power source parameters, tower parameters, overhead line parameters, grounding resistance and lightning current parameters, etc. through an interface program coded by MATLAB. Then, the data are extracted from the generated LIS files which can be obtained by executing the ATP simulation model, the occurrence of transmission lie breakdown can be determined by the relative data in LIS file. The lightning current amplitude should be reduced when the breakdown occurs, and vice the verse. Thus the initial lightning breakdown current of a transmission line with given parameters can be determined accurately by continuously changing the lightning current amplitude, which is realized by a loop computing algorithm that is coded by MATLAB software. The method proposed in this paper can generate the ATP simulation program automatically, and facilitates the lightning protection performance assessment of transmission line.

  16. Multiwavelet packet entropy and its application in transmission line fault recognition and classification.

    Science.gov (United States)

    Liu, Zhigang; Han, Zhiwei; Zhang, Yang; Zhang, Qiaoge

    2014-11-01

    Multiwavelets possess better properties than traditional wavelets. Multiwavelet packet transformation has more high-frequency information. Spectral entropy can be applied as an analysis index to the complexity or uncertainty of a signal. This paper tries to define four multiwavelet packet entropies to extract the features of different transmission line faults, and uses a radial basis function (RBF) neural network to recognize and classify 10 fault types of power transmission lines. First, the preprocessing and postprocessing problems of multiwavelets are presented. Shannon entropy and Tsallis entropy are introduced, and their difference is discussed. Second, multiwavelet packet energy entropy, time entropy, Shannon singular entropy, and Tsallis singular entropy are defined as the feature extraction methods of transmission line fault signals. Third, the plan of transmission line fault recognition using multiwavelet packet entropies and an RBF neural network is proposed. Finally, the experimental results show that the plan with the four multiwavelet packet energy entropies defined in this paper achieves better performance in fault recognition. The performance with SA4 (symmetric antisymmetric) multiwavelet packet Tsallis singular entropy is the best among the combinations of different multiwavelet packets and the four multiwavelet packet entropies.

  17. 49 CFR 192.713 - Transmission lines: Permanent field repair of imperfections and damages.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Permanent field repair of... (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS...

  18. 49 CFR 192.717 - Transmission lines: Permanent field repair of leaks.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Permanent field repair of...) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance...

  19. 49 CFR 192.715 - Transmission lines: Permanent field repair of welds.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Permanent field repair of...) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance...

  20. Fault Detection and Localization in Transmission Lines with a Static Synchronous Series Compensator

    Directory of Open Access Journals (Sweden)

    REYES-ARCHUNDIA, E.

    2015-08-01

    Full Text Available This paper proposes a fault detection and localization method for power transmission lines with a Static Synchronous Series Compensator (SSSC. The algorithm is based on applying a modal transformation to the current and voltage signals sampled at high frequencies. Then, the wavelet transform is used for calculating the current and voltage traveling waves, avoiding low frequency interference generated by the system and the SSSC. Finally, by using reflectometry principles, straightforward expressions for fault detection and localization in the transmission line are derived. The algorithm performance was tested considering several study cases, where some relevant parameters such as voltage compensation level, fault resistance and fault inception angle are varied. The results indicate that the algorithm can be successfully be used for fault detection and localization in transmission lines compensated with a SSSC. The estimated error in calculating the distance to the fault is smaller than 1% of the transmission line length. The test system is simulated in PSCAD platform and the algorithm is implemented in MATLAB software.

  1. Propagation of nonlinear waves in bi-inductance nonlinear transmission lines

    Science.gov (United States)

    Kengne, Emmanuel; Lakhssassi, Ahmed

    2014-10-01

    We consider a one-dimensional modified complex Ginzburg-Landau equation, which governs the dynamics of matter waves propagating in a discrete bi-inductance nonlinear transmission line containing a finite number of cells. Employing an extended Jacobi elliptic functions expansion method, we present new exact analytical solutions which describe the propagation of periodic and solitary waves in the considered network.

  2. Distance protection of multiple-circuit shared tower transmission lines with different voltages

    DEFF Research Database (Denmark)

    Silva, Filipe Miguel Faria da; Bak, Claus Leth

    2017-01-01

    Multiple-circuit transmission lines combining different voltage levels in one tower present extra challenges when setting a protection philosophy, as faults between voltage levels are possible. This study presents a detailed theoretical analysis of such combined faults, including the development...

  3. Simulation study on transient electric shock characteristics of human body under high voltage ac transmission lines

    Science.gov (United States)

    Huang, Tao; Zou, Yanhui; Lv, Jianhong; Yang, Jinchun; Tao, Li; Zhou, Jianfei

    2017-09-01

    Human body under high-voltage AC transmission lines will produce a certain induced voltage due to the electrostatic induction. When the human body contacts with some grounded objects, the charges transfer from the body to the ground and produce contact current which may cause transient electric shock. Using CDEGS and ATP/EMTP, the paper proposes a method for quantitatively calculating the transient electric shock characteristics. It calculates the human body voltage, discharge current and discharge energy under certain 500kV compact-type transmission lines and predicts the corresponding human feelings. The results show that the average root value of discharge current is less than 10mA when the human body is under the 500kV compact-type transmission lines and the human body is overall safe if the transmission lines satisfy the relevant design specifications. It concludes that the electric field strength above the ground should be limited to 4kV/m through the residential area for the purpose of reducing the electromagnetic impact.

  4. Fuzzy-Wavelet Based Double Line Transmission System Protection Scheme in the Presence of SVC

    Science.gov (United States)

    Goli, Ravikumar; Shaik, Abdul Gafoor; Tulasi Ram, Sankara S.

    2014-07-01

    Increasing the power transfer capability and efficient utilization of available transmission lines, improving the power system controllability and stability, power oscillation damping and voltage compensation have made strides and created Flexible AC Transmission (FACTS) devices in recent decades. Shunt FACTS devices can have adverse effects on distance protection both in steady state and transient periods. Severe under reaching is the most important problem of relay which is caused by current injection at the point of connection to the system. Current absorption of compensator leads to overreach of relay. This work presents an efficient method based on wavelet transforms, fault detection, classification and location using Fuzzy logic technique which is almost independent of fault impedance, fault distance and fault inception angle. The proposed protection scheme is found to be fast, reliable and accurate for various types of faults on transmission lines with and without Static Var compensator at different locations and with various incidence angles.

  5. A novel wavelet transform aided neural network based transmission line fault analysis method

    Energy Technology Data Exchange (ETDEWEB)

    Bhowmik, P.S. [Department of Electrical Engineering, National Institute of Technology-Durgapur, Durgapur 713 209, West Bengal (India); Purkait, P. [Department of Electrical Engineering Haldia Institute of Technology, Haldia, Midnapore (E) 721 657, West Bengal (India); Bhattacharya, K. [Department of Electrical Engineering Jadavpur University, Kolkata 700 032, West Bengal (India)

    2009-06-15

    In the present scenario of market driven business, power supply has become more like a commodity. Reliable and quality power need to be ensured to meet customer requirements. In such a situation, it is extremely important that transmission line faults be identified accurately, reliably and in quick time. Advanced signal processing tools such as discrete wavelet transform (DWT) can be used very effectively for parameterisation and characterization of the fault signals. On the other hand, properly configured neural network (NN) can be utilized for classification of the faults based on the DWT signal. The present contribution uses electromagnetic transient program (EMTP) for modeling of a real transmission system and MATLAB for DWT and NN. Various types of faults have been simulated at different locations along the transmission line and an attempt has been made to correctly identify and locate the fault. (author)

  6. Progress on corrugated waveguide components suitable for ITER ECH&CD transmission lines

    Directory of Open Access Journals (Sweden)

    Murphy C.J.

    2012-09-01

    Full Text Available The 2 MW cw requirement for ITER EC transmission lines has led GA to design a number of new and modified components, namely power monitors and polarizers to meet this requirement. In addition, the ITER transmission lines may require sliding joints or bellows to accommodate the thermal expansion of the lines and/or vessel motion. The ex-vessel sections of the EC launchers require double seal waveguides, miter bends and possibly double seal sliding joints to assure tritium retention in this region. GA has developed designs for many of these components and some of them have already been tested at high power at the JAEA RF Test Stand. Thermal analyses of the standard GA power monitor miter bend show that our standard design is suitable for 1 MW cw operation when the H-field is in the plane of the miter bend. For 2 MW cw operation a modified design, which also requires H-plane orientation, has been developed and a prototype has been fabricated and is ready for testing. For long pulse/cw operation, a 2 MW calorimetric miter bend with thermally isolated mirror has been designed and a prototype has been fabricated. Since the mirror is thermally isolated, calorimetry on the mirror cooling water can provide a measure of absorbed power. Such a miter bend, when made in a double seal version, could be useful for monitoring total power at the end of an EC transmission line just before the in-vessel section of an EC launcher. A mode analyzer using an all metal water-cooled beam splitter is being developed for use in measuring in real time the HE11 and higher order mode content or total power in EC transmission lines. Such a high power diagnostic can be very useful in optimizing the alignment of the MOU output into a transmission line and in monitoring the HE11 mode purity at various locations in a transmission line. Prior to making a 63.5 mm 170 GHz version suitable for use on ITER, several prototype 31.75 mm 110 GHz versions have been fabricated and tested at

  7. Broadband Impedance Transformer Based on Asymmetric Coupled Transmission Lines in Nonhomogeneous Medium

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Krozer, Viktor; Meincke, Peter

    2007-01-01

    A new broadband quarter-wavelength impedance transformer based on an asymmetric coupled line section is presented. The bandwidth of the coupled line transformer is extended with the help of an interconnecting transmission line. An analytical model for the transformer is developed. The analysis...... of the structure reveals that a fractional bandwidth of more than 100% at –20 dB reflection level can be achieved with such a structure. An experimental transformer circuit has been designed, fabricated and tested. Theoretical and experimental results are fair agreement and confirm the established theory...

  8. Sidney-North Yuma 230-kV Transmission Line Project, Colorado and Nebraska

    Energy Technology Data Exchange (ETDEWEB)

    1991-06-01

    This report describes the need for a 230-kV overhead transmission line to supply power from Sidney, Nebraska to eastern Colorado. The alternative scenario compared to construction of the line is No Action. Rejected alternatives include underground lines and different routing paths, with a possible extension to the Sterling area. Both scenarios are evaluated for environmental effects, cost, and consequences for the eastern Colorado region. The proposed route is determined to be the environmentally preferred choice. 120 refs., 6 figs., 13 tabs. (MHB)

  9. Controlling the transmission line shape of molecular t-stubs and potential thermoelectric applications

    DEFF Research Database (Denmark)

    Stadler, Robert; Markussen, Troels

    2011-01-01

    been only empirically found for just a few rather complex organic molecules where the origins of the line shapes relation to molecular structure were not resolved. In the present, work we introduce a method to analyze the structure dependence of the asymmetry of interference dips from simple two site......Asymmetric line shapes can occur in the transmission function describing electron transport in the vicinity of a minimum caused by quantum interference effects. Such asymmetry can be used to increase the thermoelectric efficiency of molecular junctions. So far, however, asymmetric line shapes have...

  10. New magnet transport system for the LHC beam transfer lines

    CERN Multimedia

    Patrice Loïez

    2003-01-01

    The first of 700 magnets has been installed in one of the two transfer tunnels built to transfer the SPS beam into the LHC. The start of this first installation phase of the LHC transfer lines provides the opportunity to launch a new and highly original modular system for transporting and installing all kinds of magnets in very narrow tunnels. The system (pictured here in one of the tunnels) is based on very compact bogies, up to four of which can be coupled together to form a convoy. The wheels are fitted with individual motors enabling them to swivel through an angle of 90° and the convoy to move laterally. The lead vehicle is powered by an electric rail set into the roof of the tunnel. The system is backed up by electrical batteries that enable it to operate in the absence of an outside power source or in the event of power failure. Last but not least, for the long-distance transport of magnets, it can be optically guided by a line traced on the tunnel floor. The convoy moves through the particularly narr...

  11. Data-Mining-Based Intelligent Differential Relaying for Transmission Lines Including UPFC and Wind Farms.

    Science.gov (United States)

    Jena, Manas Kumar; Samantaray, Subhransu Ranjan

    2016-01-01

    This paper presents a data-mining-based intelligent differential relaying scheme for transmission lines, including flexible ac transmission system device, such as unified power flow controller (UPFC) and wind farms. Initially, the current and voltage signals are processed through extended Kalman filter phasor measurement unit for phasor estimation, and 21 potential features are computed at both ends of the line. Once the features are extracted at both ends, the corresponding differential features are derived. These differential features are fed to a data-mining model known as decision tree (DT) to provide the final relaying decision. The proposed technique has been extensively tested for single-circuit transmission line, including UPFC and wind farms with in-feed, double-circuit line with UPFC on one line and wind farm as one of the substations with wide variations in operating parameters. The test results obtained from simulation as well as in real-time digital simulator testing indicate that the DT-based intelligent differential relaying scheme is highly reliable and accurate with a response time of 2.25 cycles from the fault inception.

  12. A study on accurate fault location algorithm for parallel transmission line with a teed connection

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Yu.; Chunju, Fan; Gong, Zhendong [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2010-07-15

    Teed connecting parallel transmission lines frequently subject a variety of technical problems in the view of protection engineering. These problems are mainly due to the mutual coupling between lines and the multiple branch of teed connection, which requires choosing faulted branch before fault location. A new accurate fault location algorithm for parallel transmission line with a teed connection is introduced in this paper. Depending on six-sequence fault component method, the coupled transmission equations are transformed into decoupled ones. Based on the detailed analysis of peculiar characteristic of teed connection, the differential positive sequence component measurement, which is one of the six-sequence fault components, is used to implement fault location for parallel line with a teed connection. The new location algorithm makes full use of the decoupled mode and the teed structure. It is independent of source impedance, fault type, fault resistance and mutual coupling between parallel lines. The algorithm has been tested by EMTP simulations, which indicates that this location method obtains high accuracy under various fault conditions. (author)

  13. Rolled-up transmission line structure for a radiofrequency integrated circuit (RFIC)

    Science.gov (United States)

    Li, Xiuling; Huang, Wen

    2015-04-28

    A rolled-up transmission line structure for a radiofrequency integrated circuit (RFIC) comprises a multilayer sheet in a rolled configuration comprising multiple turns about a longitudinal axis, where the multilayer sheet comprises a conductive pattern layer on a strain-relieved layer. The conductive pattern layer comprises a first conductive film and a second conductive film separated from the first conductive film in a rolling direction. In the rolled configuration, the first conductive film surrounds the longitudinal axis, and the second conductive film surrounds the first conductive film. The first conductive film serves as a signal line and the second conductive film serves as a conductive shield for the rolled-up transmission line structure.

  14. Dipole corrector magnets for the LBNE beam line

    Energy Technology Data Exchange (ETDEWEB)

    Yu, M.; Velev, G.; Harding, D.; /Fermilab

    2011-03-01

    The conceptual design of a new dipole corrector magnet has been thoroughly studied. The planned Long-Baseline Neutrino Experiment (LBNE) beam line will require correctors capable of greater range and linearity than existing correctors, so a new design is proposed based on the horizontal trim dipole correctors built for the Main Injector synchrotron at Fermilab. The gap, pole shape, length, and number of conductor turns remain the same. To allow operation over a wider range of excitations without overheating, the conductor size is increased, and to maintain better linearity, the back leg thickness is increased. The magnetic simulation was done using ANSYS to optimize the shape and the size of the yoke. The thermal performance was also modeled and analyzed.

  15. Holomorphic variables in magnetized brane models with continuous Wilson lines

    CERN Document Server

    Camara, Pablo G; Dudas, Emilian

    2010-01-01

    We analyze the action of the target-space modular group in toroidal type IIB orientifold compactifications with magnetized D-branes and continuous Wilson lines. The transformation of matter fields agree with that of twisted fields in heterotic compactifications, constituting a check of type I/heterotic duality. We identify the holomorphic N = 1 variables for these compactifications. Matter fields and closed string moduli are both redefined by open string moduli. The redefinition of matter fields can be read directly from the perturbative Yukawa couplings, whereas closed string moduli redefinitions are obtained from D-brane instanton superpotential couplings. The resulting expressions reproduce and generalize, in the presence of internal magnetic fields, previous results in the literature.

  16. Acoustic transmission line metamaterial with negative/zero/positive refractive index

    Science.gov (United States)

    Bongard, Frédéric; Lissek, Hervé; Mosig, Juan R.

    2010-09-01

    A one-dimensional acoustic negative refractive index metamaterial based on the transmission line approach is presented. This structure implements the dual transmission line concept extensively investigated in microwave engineering. It consists of an acoustic waveguide periodically loaded with membranes realizing the function of series “capacitances” and transversally connected open channels realizing shunt “inductances.” Transmission line based metamaterials can exhibit a negative refractive index without relying on resonance phenomena, which results in a bandwidth of operation much broader than that observed in resonant devices. In the present case, the negative refractive index band extends over almost one octave, from 0.6 to 1 kHz. The developed structure also exhibits a seamless transition between the negative and positive refractive index bands with a zero index at the transition frequency of 1 kHz. At this frequency, the unit cell is only one tenth of the wavelength. Simple acoustic circuit models are introduced, which allow efficient designs both in terms of dispersion and impedance, while accurately describing all the physical phenomena. Using this approach, a good matching at the structure terminations is achieved. Full-wave simulations, made for a 10-cell-long structure, confirm the good performances in terms of dispersion diagram, Bloch impedance, and reflection and transmission coefficients.

  17. A Pilot Directional Protection for HVDC Transmission Line Based on Relative Entropy of Wavelet Energy

    Directory of Open Access Journals (Sweden)

    Sheng Lin

    2015-07-01

    Full Text Available On the basis of analyzing high-voltage direct current (HVDC transmission system and its fault superimposed circuit, the direction of the fault components of the voltage and the current measured at one end of transmission line is certified to be different for internal faults and external faults. As an estimate of the differences between two signals, relative entropy is an effective parameter for recognizing transient signals in HVDC transmission lines. In this paper, the relative entropy of wavelet energy is applied to distinguish internal fault from external fault. For internal faults, the directions of fault components of voltage and current are opposite at the two ends of the transmission line, indicating a huge difference of wavelet energy relative entropy; for external faults, the directions are identical, indicating a small difference. The simulation results based on PSCAD/EMTDC show that the proposed pilot protection system acts accurately for faults under different conditions, and its performance is not affected by fault type, fault location, fault resistance and noise.

  18. Development of a Software Tool for Calculating Transmission Line Parameters and Updating Related Databases

    Science.gov (United States)

    Xiu, Wanjing; Liao, Yuan

    2014-12-01

    Transmission lines are essential components of electric power grids. Diverse power system applications and simulation based studies require transmission line parameters including series resistance, reactance, and shunt susceptance, and accurate parameters are pivotal in ensuring the accuracy of analyses and reliable system operation. Commercial software packages for performing power system studies usually have their own databases that store the power system model including line parameters. When there is a physical system model change, the corresponding component in the database of the software packages will need to be modified. Manually updating line parameters are tedious and error-prone. This paper proposes a solution for streamlining the calculation of line parameters and updating of their values in respective software databases. The algorithms used for calculating the values of line parameters are described. The software developed for implementing the solution is described, and typical results are presented. The proposed solution is developed for a utility and has a potential to be put into use by other utilities.

  19. Application of reliability based design concepts to transmission line structure foundations. Part 2

    International Nuclear Information System (INIS)

    DiGioia, A.M. Jr.; Rojas-Gonzalez, L.F.

    1991-01-01

    The application of reliability based design (RBD) methods to transmission line structure foundations has developed somewhat more slowly than that for the other structural components in line systems. In a previous paper, a procedure was proposed for the design of transmission line structures foundations using a probability based load and resistance factor design (LRFD) format. This procedure involved the determination of a foundation strength factor, φ F , which was used as a multiplier of the calculated nominal design strength to estimate the five percent exclusion limit strength required in the calculated nominal design strength to estimate the five percent exclusion limit strength required in the LRFD equation. Statistical analyses of results from full-scale load tests were used to obtain φ F values applicable to various nominal design strength equations and for drilled shafts subjected to uplift loads. These results clearly illustrated the significant economic benefits of conducting more detailed subsurface investigations for the design of transmission line structure foundations. A design example was also presented. In this paper the proposed procedure is extended to laterally load drilled shafts

  20. Magnetic imaging with a Zernike-type phase plate in a transmission electron microscope

    DEFF Research Database (Denmark)

    Pollard, Shawn; Malac, Marek; Beleggia, Marco

    2013-01-01

    We demonstrate the use of a hole-free phase plate (HFPP) for magnetic imaging in transmission electron microscopy by mapping the domain structure in PrDyFeB samples. The HFPP, a Zernike-like imaging method, allows for detecting magnetic signals in-focus to correlate the sample crystal structure a...

  1. Study on frequency characteristics of wireless power transmission system based on magnetic coupling resonance

    Science.gov (United States)

    Liang, L. H.; Liu, Z. Z.; Hou, Y. J.; Zeng, H.; Yue, Z. K.; Cui, S.

    2017-11-01

    In order to study the frequency characteristics of the wireless energy transmission system based on the magnetic coupling resonance, a circuit model based on the magnetic coupling resonant wireless energy transmission system is established. The influence of the load on the frequency characteristics of the wireless power transmission system is analysed. The circuit coupling theory is used to derive the minimum load required to suppress frequency splitting. Simulation and experimental results verify that when the load size is lower than a certain value, the system will appear frequency splitting, increasing the load size can effectively suppress the frequency splitting phenomenon. The power regulation scheme of the wireless charging system based on magnetic coupling resonance is given. This study provides a theoretical basis for load selection and power regulation of wireless power transmission systems.

  2. Environmental Assessment of the Gering-Stegall 115-kV Transmission Line Consolidation Project, Scotts Bluff County, Nebraska

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    The Department of Energy (DOE), Western Area Power Administration (Western) proposes to consolidate segments of two transmission lines near the Gering Substation in Gering, Nebraska. The transmission lines are both located in Scotts Bluff County, Nebraska. The transmission lines are both located in Scotts Bluff County, Nebraska, within the city of Gering. Presently, there are three parallel 115-kilovolt (kV) transmission lines on separate rights-of-way (ROW) that terminate at the Gering Substation. The project would include dismantling the Archer-Gering wood-pole transmission line and rebuilding the remaining two lines on single-pole steel double circuit structures. The project would consolidate the Gering-Stegall North and Gering-Stegall South 115-kV transmission lines on to one ROW for a 1.33-mile segment between the Gering Substation and a point west of the Gering Landfill. All existing wood-pole H-frame structures would be removed, and the Gering-Stegall North and South ROWs abandoned. Western is responsible for the design, construction, operation, and maintenance of the line. Western prepared an environmental assessment (EA) that analyzed the potential environmental impacts of the proposed construction, operation, and maintenance of the 115-kV transmission line consolidation. Based on the analyses in the EA, the DOE finds that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act of 1969 (NEPA).

  3. Environmental Assessment of the Gering-Stegall 115-kV Transmission Line Consolidation Project, Scotts Bluff County, Nebraska

    International Nuclear Information System (INIS)

    1995-05-01

    The Department of Energy (DOE), Western Area Power Administration (Western) proposes to consolidate segments of two transmission lines near the Gering Substation in Gering, Nebraska. The transmission lines are both located in Scotts Bluff County, Nebraska. The transmission lines are both located in Scotts Bluff County, Nebraska, within the city of Gering. Presently, there are three parallel 115-kilovolt (kV) transmission lines on separate rights-of-way (ROW) that terminate at the Gering Substation. The project would include dismantling the Archer-Gering wood-pole transmission line and rebuilding the remaining two lines on single-pole steel double circuit structures. The project would consolidate the Gering-Stegall North and Gering-Stegall South 115-kV transmission lines on to one ROW for a 1.33-mile segment between the Gering Substation and a point west of the Gering Landfill. All existing wood-pole H-frame structures would be removed, and the Gering-Stegall North and South ROWs abandoned. Western is responsible for the design, construction, operation, and maintenance of the line. Western prepared an environmental assessment (EA) that analyzed the potential environmental impacts of the proposed construction, operation, and maintenance of the 115-kV transmission line consolidation. Based on the analyses in the EA, the DOE finds that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act of 1969 (NEPA)

  4. Study of HV Dielectrics for High Frequency Operation in Linear & Nonlinear Transmission Lines & Simulation & Development of Hybrid Nonlinear Lines for RF Generation

    Science.gov (United States)

    2015-08-27

    the negative voltage reflection at the load, which decreases the biased line Bragg frequency and in turn the oscilltation frequency as capacitance ...work is to describe the research on lumped capacitive nonlinear transmission lines (NLTLs) developed during period 2013-2014. As lumped capacitive ...voltage line built with varying capacitance diodes, called varactors, as these components show higher nonlinearity than commercial ceramic capacitors. To

  5. Long-Haul Dense Space Division Multiplexed Transmission over Low-Crosstalk Heterogeneous 32-Core Transmission Line Using Partial Recirculating Loop System

    DEFF Research Database (Denmark)

    Mizuno, Takayuki; Shibahara, Kohki; Ye, Feihong

    2017-01-01

    In this paper, we present long-haul 32-core dense space division multiplexed (DSDM) unidirectional transmission over a single-mode multicore transmission line. We developed a low-crosstalk heterogeneous 32-core fiber with a square lattice arrangement, and a novel partial recirculating loop system...

  6. The Quadrupole Magnets for the LHC Injection Transfer Lines

    CERN Document Server

    Chertok, I; Churkin, I N; Giesch, Manfred; Golubenko, O B; Kalbreier, Willi; Kouba, G; Mejidzade, V; Mikhailov, S; Steshov, A; Sukhanov, A; Sukhina, B; Schirm, K M; Weisse, E

    2000-01-01

    Two injection transfer lines, each about 2.8 km long, are being built to transfer protons at 450 GeV from the Super Proton Synchrotron (SPS) to the Large Hadron Collider (LHC). A total of 180 quadrupole magnets are required; they are produced in the framework of the contribution of the Russian Federation to the construction of the LHC. The classical quadrupoles, built from laminated steel cores and copper coils, have a core length of 1.4 m, an inscribed diameter of 32 mm and a strength of 53.5 T/m at a current of 530 A. The total weight of one magnet is 1.1 ton. For obtaining the required field quality at the small inscribed diameter, great care in the stamping of the laminations and the assembly of quadrants is necessary. Special instruments have been developed to measure, with a precision of some mm, the variations of the pole gaps over the full length of the magnet and correlate them to the obtained field distribution. The design has been developed in a collaboration between BINP and CERN. Fabrication and ...

  7. Sensor network for monitoring of power transmission lines; Sensornetzwerk zum Monitoring von Hochspannungsleitungen

    Energy Technology Data Exchange (ETDEWEB)

    Voigt, S. [Technische Univ. Chemnitz (Germany); Wolfrum, J.; Pfeiffer, M. [envia Netzservice GmbH, Halle (Germany)] [and others

    2012-07-01

    In this paper, we present an autonomous sensor network for monitoring and power load optimization of high-voltage power lines. We also discuss results from tests in high-voltage laboratory and on 110 kV power lines. The system consists of several sensor nodes, which are directly mounted to the power line conductor. Additional components on the pylons are not needed. The energy required for the operation of the sensor nodes is harvested from the electric fringing field of the power lines. The sensor data consisting of temperature, magnitude of the current, and conductor sag is passed along the chain in the 2.4 GHz ISM frequency band and collected by a base station. In the base station, which is located at the substation, the incoming data are processed in the form of a web server with a database system and provided to the control station of the electric power transmission system operators. (orig.)

  8. Quasi-Optical Transmission Lines for ECRH on TJ-II Stellarator

    International Nuclear Information System (INIS)

    Fernandez, A.; Likin, K.; Martin, R.; Cappa, A.; Cepero, J.R.

    1999-01-01

    Two mirror lines are used to transmit ht microwave power from the powerful microwave generators to the TJ-II plasmas. Both lines have been tested at nominal power level and they are now in operation. This paper is devoted to the final design of the transmission lines and their testing. Before starting operation at high power level measurements of the wave beam parameters at low power level were made. Two horn antennae were designed to simulate the gyrotron output. Numerical simulations of the far field radiation pattern of the antennae were made, a computer code based on Huygens diffraction theory was developed to simulate the propagation of the beam along a mirror line. A comparison of the theoretical and the experimental results is also presented here. (Author)

  9. Accurate fault location algorithm for transmission line in the presence of series connected FACTS devices

    Energy Technology Data Exchange (ETDEWEB)

    Sadeh, Javad; Adinehzadeh, Aniseh [Department of Electrical Engineering, Faculty of Engineering, Ferdowsi University of Mashhad, P.O. Box 91775-1111, Mashhad (Iran)

    2010-05-15

    This paper presents a new and accurate fault location algorithm based on distributed time domain line model for a transmission line compensated with series connected FACTS device. In the proposed algorithm, in order to compute the voltage drop across the series device during the fault period, the series device model and knowledge about the operating mode of the compensating device are not utilized. For this reason, the proposed technique can be easily applied to any series FACTS compensated line. Samples of voltage and current at both ends of the line are taken synchronously and used to calculate the location and resistance of the fault. The proposed algorithm is not sensitive to fault resistance and fault inception angle and does not require any knowledge of equivalent source impedances. This method has been tested using EMTP/ATP model of a 400 kV, 300 km transmission line compensated with a series FACTS device. The results of computer simulations for different operating conditions demonstrate the very high accuracy and robustness of the algorithm. (author)

  10. Transmission line model for coupled rectangular double split‐ring resonators

    DEFF Research Database (Denmark)

    Yan, Lei; Tang, Meng; Krozer, Viktor

    2011-01-01

    In this work, a model based on a coupled transmission line formulation is developed for microstrip rectangular double split‐ring resonators (DSRRs). This model allows using the physical dimensions of the DSRRs as an input avoiding commonly used extraction of equivalent parameters. The model...... DSRRs, which allows for an accurate modeling of densely packed multiresonator structures. The model is verified by comparison with measured DSRRs‐loaded microstrip line performance. The developed model can be effectively used to save computation resources associated with full wave electromagnetic...

  11. Definition of a matrix of the generalized parameters asymmetrical multiphase transmission lines

    Directory of Open Access Journals (Sweden)

    Suslov V.M.

    2005-12-01

    Full Text Available Idle time, without introduction of wave characteristics, algorithm of definition of a matrix of the generalized parameters asymmetrical multiphase transmission lines is offered. Definition of a matrix of parameters is based on a matrix primary specific of parameters of line and simple iterative procedure. The amount of iterations of iterative procedure is determined by a set error of performance of the resulted matrix ratio between separate blocks of a determined matrix. The given error is connected by close image of with a margin error determined matrix.

  12. Transmission line theory for long plasma production by radio frequency discharges between parallel-plate electrodes

    International Nuclear Information System (INIS)

    Nonaka, S.

    1991-01-01

    In order to seek for a radio frequency (RF) eigen-mode of waves in producing a plasma between a pair of long dielectric-covered parallel-plate RF electrodes, this paper analyzed all normal modes propagating along the electrodes by solving Maxwell's equations. The result showed that only an odd surface wave mode will produce the plasma in usual experimental conditions, which will become a basic transmission line theory when use of such long electrodes for on-line mass-production of amorphous silicon solar cells

  13. Stress Analysis of Boom of Special Mobile Crane for Plain Region in Transmission Line

    Science.gov (United States)

    Qin, Jian; Shao, Tao; Chen, Jun; Wan, Jiancheng; Li, Zhonghuan; Jiang, Ming

    2017-10-01

    Basis of the boom force analysis of special mobile crane for plain region in transmission line, the load type of boom design is confirmed. According to the different combinations of boom sections, the composite pattern of the different boom length is obtained to suit the actual conditions of boom overlapping. The large deformation model is employed with FEM to simulate the stress distribution of boom, and the calculation results are checked. The performance curves of rated load with different arm length and different working range are obtained, which ensures the lifting capacity of special mobile crane meeting the requirement of tower erection of transmission line. The proposed FEM of boom of mobile crane would provide certain guiding and reference to the boom design.

  14. On-line nuclear ash gauge for coal based on gamma-ray transmission techniques

    International Nuclear Information System (INIS)

    Rizk, R.A.M.; El-Kateb, A.H.; Abdul-Kader, A.M.

    1999-01-01

    Developments and applications of on-line nuclear gauges in the coal industry are highly requested. A nuclear ash gauge for coal, based on γ-ray transmission techniques is developed. Single and dual energy γ-ray beams are used to determine the ash content of coal. The percentage ash content as a function of the γ-ray intensities transmitted through coal samples is measured and sensitivity curves are obtained. An empirical formulation relating the ash content values to the γ-ray intensities is derived. Preliminary results show that both single and dual energy γ-ray transmission techniques can be used to give a rapid on-line estimation of the ash concentration values in coal with low cost and reasonable accuracy, but the dual one is much preferable. (author)

  15. Conducting properties of classical transmission lines with Ornstein-Uhlenbeck type disorder

    International Nuclear Information System (INIS)

    Lazo, E.; Diez, E.

    2011-01-01

    In this work we study the behavior of bands of extended states and localized states which appear in classical disordered electrical transmission lines, when we use a ternary map and the Ornstein-Uhlenbeck process to generate the long-range correlated disorder, instead of using the Fourier filtering method. By performing finite-size scaling we obtain the asymptotic value of the map parameter b in the thermodynamic limit in a selected range of values of the parameters γ and C of the Ornstein-Uhlenbeck process. With these data we obtain the phase diagrams which separate the localized states from the extended states. These are the fundamental results of this article. - Highlights: → We study disordered classical transmission lines. → We use the Ornstein-Uhlenbeck process to generate long-range correlated disorder. → We obtain the phase diagram of the transition in the thermodynamic limit.

  16. Performance Analysis of the ITER Plasma Position Reflectometry (PPR) Ex-vessel Transmission Lines

    Science.gov (United States)

    Martínez-Fernández, J.; Simonetto, A.; Cappa, Á.; Rincón, M. E.; Cabrera, S.; Ramos, F. J.

    2018-03-01

    As the design of the ITER Plasma Position Reflectometry (PPR) diagnostic progresses, some segments of the transmission line have become fully specified and estimations of their performance can already be obtained. This work presents the calculations carried out for the longest section of the PPR, which is in final state of design and will be the main contributor to the total system performance. Considering the 88.9 mm circular corrugated waveguide (CCWG) that was previously chosen, signal degradation calculations have been performed. Different degradation sources have been studied: ohmic attenuation losses for CCWG; mode conversion losses for gaps, mitre bends, waveguide sag and different types of misalignments; reflection and absorption losses due to microwave windows and coupling losses to free space Gaussian beam. Contributions from all these sources have been integrated to give a global estimation of performance in the transmission lines segments under study.

  17. Transmission lines implementation on HDI flex circuits for the CMS tracker upgrade

    International Nuclear Information System (INIS)

    Blanchot, G.; Gadek, T.; Honma, A.; Kovacs, M.; Rose, P.; Canio, F. De; Traversi, G.

    2016-01-01

    The upgrade of the CMS tracker at the HL-LHC relies on hybrid modules built on high density interconnecting flexible circuits. They contain several flip chip readout ASICs having high speed digital ports required for configuration and data readout, implemented as customized Scalable Low-Voltage Signalling (SLVS) differential pairs. This paper presents the connectivity requirements on the CMS tracker hybrids; it compares several transmission line implementations in terms of board area, achievable impedances and expected crosstalk. The properties obtained by means of simulations are compared with measurements made on a dedicated test circuit. The different transmission line implementations are also tested using a custom 65nm SLVS driver and receiver prototype ASIC

  18. Monitoring of Overhead Transmission Lines: A Review from the Perspective of Contactless Technologies

    Science.gov (United States)

    Khawaja, Arsalan Habib; Huang, Qi; Khan, Zeashan Hameed

    2017-12-01

    This paper describes a comprehensive review of non-contact technologies for overhead power transmission lines. Due to ever increasing emphasis on reducing accidents and speeding up diagnosis for automatically controlled grids, real time remote sensing and actuation is the new horizon for smart grid implementation. The technology overview with emphasis on the practical implementation of advanced non-contact technologies is discussed in this paper while considering optimization of the high voltage transmission lines parameters. In case of fault, the voltage and the current exceed limits of operation and hence real time reporting for control and diagnosis is a critical requirement. This paper aims to form a strong foundation for control and diagnosis of future power distribution systems so that a practitioner or researcher can make choices for a workable solution in smart grid implementation based on non-contact sensing.

  19. Rényi entropies of electrical transmission lines with Fibonacci distribution of inductances

    International Nuclear Information System (INIS)

    Lazo, E.; Mellado, F.; Saavedra, E.

    2012-01-01

    We study classical dual transmission lines with constant capacitances C j =C 0 , ∀j, when we distribute two inductance values L A and L B according to the Fibonacci sequence. Using the electric current function I j (ω), we study the normalized localization length Λ(ω), the Rényi entropies R m (ω) and the normalized information length β(ω). We found three kinds of behavior of the I j (ω) function: localized, extended and intermediate. In addition, it is found that the transmission line with Fibonacci distribution of inductances shows a behavior characteristic of quasi-periodic systems, namely, a self-similar frequency spectrum, where each subband is divided into three subbands, but the number of global subbands is greater than four.

  20. Rényi entropies of electrical transmission lines with Fibonacci distribution of inductances

    Energy Technology Data Exchange (ETDEWEB)

    Lazo, E., E-mail: elazo@uta.cl [Departamento de Física, Facultad de Ciencias, Universidad de Tarapacá, Arica (Chile); Mellado, F. [Departamento de Física, Facultad de Ciencias, Universidad de Tarapacá, Arica (Chile); Escuela Universitaria de Ingeniería Eléctrica-Electrónica, Universidad de Tarapacá, Arica (Chile); Saavedra, E. [Departamento de Física, Facultad de Ciencias, Universidad de Tarapacá, Arica (Chile)

    2012-10-01

    We study classical dual transmission lines with constant capacitances C{sub j}=C{sub 0}, ∀j, when we distribute two inductance values L{sub A} and L{sub B} according to the Fibonacci sequence. Using the electric current function I{sub j}(ω), we study the normalized localization length Λ(ω), the Rényi entropies R{sub m}(ω) and the normalized information length β(ω). We found three kinds of behavior of the I{sub j}(ω) function: localized, extended and intermediate. In addition, it is found that the transmission line with Fibonacci distribution of inductances shows a behavior characteristic of quasi-periodic systems, namely, a self-similar frequency spectrum, where each subband is divided into three subbands, but the number of global subbands is greater than four.

  1. Minimal inductance for axisymmetric transmission lines with radially dependent anode-cathode gap

    Directory of Open Access Journals (Sweden)

    Eduardo M. Waisman

    2009-09-01

    Full Text Available We extend the variational calculus technique for inductance minimization of constant gap axisymmetric transmission lines (TL, introduced by Hurricane [J. Appl. Phys. 95, 4503 (2004JAPIAU0021-897910.1063/1.1687986], to the case in which the anode-cathode gap is a linear function of the midgap radius. The full analytic optimal midgap solution curve z(r yielding minimum inductance is obtained in terms of a single parameter ρ_{0}, determined numerically by imposing that z(r goes through prescribed end points. The radius of curvature ρ(r of the optimal curve is obtained everywhere the function is defined, even outside of the end point range, and it is shown that a convenient choice is ρ_{0}=ρ(0. The value of the transmission line inductance is calculated by 1D numerical quadrature. A simple numerical technique is introduced for TL with nonlinear radial gap dependence.

  2. A long analog transmission line for the VELO read-out

    CERN Document Server

    Frei, R

    2001-01-01

    The radiation level in the LHCb cavern strongly suggests to place the L1 Electronics behind the concrete wall to avoid Single Event Upset (SEU) in FPGA. For the VELO this implies the necessity for ~60 m long transmission lines from the VELO vacuum vessel to the L1 electronics. This note reports a feasibility study for such a long connection using twisted pair cables.

  3. Efficient production of hot plasmas through multiple-wire implosion in transmission line generators

    International Nuclear Information System (INIS)

    Bloomberg, H.W.

    1980-01-01

    Model equations for the implosion of multiple-wire arrays mounted across the electrodes of a transmission line generator are used to obtain an expression for the energy-coupling efficiency. For a useful class of imploding loads, the efficiency is shown to depend on a single dimensionless parameter. Furthermore, the efficiency curve has a maximum, and this permits an explicit optimization of the wire load parameters in terms of the machine parameters

  4. Termination for a superconducting power transmission line including a horizontal cryogenic bushing

    Science.gov (United States)

    Minati, Kurt F.; Morgan, Gerry H.; McNerney, Andrew J.; Schauer, Felix

    1984-01-01

    A termination for a superconducting power transmission line is disclosed which is comprised of a standard air entrance insulated vertical bushing with an elbow, a horizontal cryogenic bushing linking the pressurized cryogenic cable environment to the ambient temperature bushing and a stress cone which terminates the cable outer shield and transforms the large radial voltage gradient in the cable dielectric into a much lower radial voltage gradient in the high density helium coolant at the cold end of the cryogenic bushing.

  5. Thermal fluctuations in resonant motion of fluxons on a Josephson transmission line: Theory and experiment

    DEFF Research Database (Denmark)

    Jørgensen, E.; Koshelets, V. P.; Monaco, Roberto

    1982-01-01

    The radiation emission from long and narrow Josephson tunnel junctions dc-current biased on zero-field steps has been ascribed to resonant motion of fluxons on the transmission line. Within this dynamic model a theoretical expression for the radiation linewidth is derived from a full statistical ...... treatment of thermal fluctuations in the fluxon velocity. The result appears to be very general and is corroborated by experimental determination of linewidth and frequency of radiation emitted from overlap Nb-I-Pb junctions....

  6. Attenuation, phase velocity and current density distribution in high critical temperature superconducting planar transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Cabon, B.; Vu Dinh, T.; Chilo, J. [URA CNRS 833, Grenoble (France). Lab. d`Electromagnetisme

    1995-05-01

    Electromagnetic calculation of propagation parameters for high {Tc} superconductive coplanar and microstrip transmission lines is presented. Calculations are performed by a nodal circuit simulator (SPICE), with possibility of direct interfacing with CAE standards. The results are in good agreement with data obtained with a full-wave analysis and CPU time is much smaller than in standard MW applications. Then, current density distributions are shown.

  7. Critical parameters affecting the design of high frequency transmission lines in standard CMOS technology

    KAUST Repository

    Al Attar, Talal

    2017-05-13

    Different structures of transmission lines were designed and fabricated in standard CMOS technology to estimate some critical parameters including the RMS value of the surface roughness and the loss tangent. The input impedances for frequencies up to 50 GHz were modeled and compared with measurements. The results demonstrated a strong correlation between the used model with the proposed coefficients and the measured results, attesting the robustness of the model and the reliability of the incorporated coefficients values.

  8. Short-Circuit Calculations for a Transmission Line in the Algerian Power Network Compensated by Thyristor Controlled Voltage Regulator

    Directory of Open Access Journals (Sweden)

    ZELLAGUI Mohamed

    2014-10-01

    Full Text Available In this paper, the impact of using the Thyristor Controlled Voltage Regulator (TCVR on short-circuit calculations is studied for a high voltage transmission line in case of a phase to earth fault in the presence of a fault resistance (RF. A 400 kV single transmission line, in the Algerian power network, is used for this study where the line is compensated by TCVR FACTS device to control the voltage and active power of the line. The impact of the fault resistance is studied to reflect its effect on short-circuit calculations including symmetrical current components, transmission line currents, voltage symmetrical components, and transmission line voltages, without and with TCVR. The obtained simulation results match the presented theoretical analysis.

  9. Magnet power supply and beam line control for a secondary beam line K6

    International Nuclear Information System (INIS)

    Suzuki, Y.; Takasaki, M.; Minakawa, M.; Ishii, H.; Kato, Y.; Ieiri, M.; Tanaka, K.H.; Noumi, H.; Yamanoi, Y.

    1992-01-01

    K6 is a secondary separated-beam line with momentum range up to 2.0 GeV/c in the north experimental hall at the KEK 12 GeV Proton Synchrotron (KEK-PS). On the construction, newly developed magnet power supplies (MPSs), in each of them a microprocessor is embedded, are introduced. The features of the MPS are as follows: 1, The MPS is connected to an upper-level beam line controller (BLC) by GPIB highway for exchanging simple messages. 2, All the operations of the MPS are supervised by the microprocessor, which has its individual parameters and fault messages. It reduces the load of the upper-level controller. 3, The MPS has functions to inspect itself and to report the result. It saves much time and labor of maintenance. (author)

  10. Assessment of surge arrester failure rate and application studies in Hellenic high voltage transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Christodoulou, C.A.; Fotis, G.P.; Gonos, I.F.; Stathopulos, I.A. [National Technical University of Athens, School of Electrical and Computer Engineering, High Voltage Laboratory, 9 Iroon Politechniou St., Zografou Campus, 157 80 Athens (Greece); Ekonomou, L. [A.S.PE.T.E. - School of Pedagogical and Technological Education, Department of Electrical Engineering Educators, N. Heraklion, 141 21 Athens (Greece)

    2010-02-15

    The use of transmission line surge arresters to improve the lightning performance of transmission lines is becoming more common. Especially in areas with high soil resistivity and ground flash density, surge arresters constitute the most effective protection mean. In this paper a methodology for assessing the surge arrester failure rate based on the electrogeometrical model is presented. Critical currents that exceed arresters rated energy stress were estimated by the use of a simulation tool. The methodology is applied on operating Hellenic transmission lines of 150 kV. Several case studies are analyzed by installing surge arresters on different intervals, in relation to the region's tower footing resistance and the ground flash density. The obtained results are compared with real records of outage rate showing the effectiveness of the surge arresters in the reduction of the recorded failure rate. The presented methodology can be proved valuable to the studies of electric power systems designers intending in a more effective lightning protection, reducing the operational costs and providing continuity of service. (author)

  11. Simulation Analysis of Transmission-Line Impedance Transformers for Petawatt-Class Pulsed Power Accelerators

    International Nuclear Information System (INIS)

    Hu Yixiang; Qiu Aici; Sun Fengju; Huang Tao; Cong Peitian; Wang Liangping; Zeng Jiangtao; Li Yan; Zhang Xinjun; Lei Tianshi

    2011-01-01

    Based on the transmission line code TLCODE, a 1D circuit model for a transmission-line impedance transformer was developed and the simulation results were compared with those in the literature. The model was used to quantify the efficiencies of voltage-transport, energy-transport and power-transport for a transmission-line impedance transformer as functions of ψ (the ratio of the output impedance to the input impedance of the transformer) and Γ (the ratio of the pulse width to the one-way transit time of the transformer) under a large scale of m (the coefficient of the generalized exponential impedance profile). Simulation results suggest that with the increase in Γ, from 0 to ∞, the power transport efficiency first increases and then decreases. The maximum power transport efficiency can reach 90% or even higher for an exponential impedance profile (m = 1). With a consideration of dissipative loss in the dielectric and electrodes of the transformer, two representative designs of the water-insulated transformer are investigated for the next generation of petawatt-class z-pinch drivers. It is found that the dissipative losses in the electrodes are negligibly small, below 0.1%, but the dissipative loss in the water dielectric is about 1% to 4%. (fusion engineering)

  12. Improved Fault Classification in Series Compensated Transmission Line: Comparative Evaluation of Chebyshev Neural Network Training Algorithms.

    Science.gov (United States)

    Vyas, Bhargav Y; Das, Biswarup; Maheshwari, Rudra Prakash

    2016-08-01

    This paper presents the Chebyshev neural network (ChNN) as an improved artificial intelligence technique for power system protection studies and examines the performances of two ChNN learning algorithms for fault classification of series compensated transmission line. The training algorithms are least-square Levenberg-Marquardt (LSLM) and recursive least-square algorithm with forgetting factor (RLSFF). The performances of these algorithms are assessed based on their generalization capability in relating the fault current parameters with an event of fault in the transmission line. The proposed algorithm is fast in response as it utilizes postfault samples of three phase currents measured at the relaying end corresponding to half-cycle duration only. After being trained with only a small part of the generated fault data, the algorithms have been tested over a large number of fault cases with wide variation of system and fault parameters. Based on the studies carried out in this paper, it has been found that although the RLSFF algorithm is faster for training the ChNN in the fault classification application for series compensated transmission lines, the LSLM algorithm has the best accuracy in testing. The results prove that the proposed ChNN-based method is accurate, fast, easy to design, and immune to the level of compensations. Thus, it is suitable for digital relaying applications.

  13. Alleviation SSR and Low Frequency Power Oscillations in Series Compensated Transmission Line using SVC Supplementary Controllers

    Science.gov (United States)

    Kumar, Sanjiv; Kumar, Narendra

    2017-06-01

    In this work, supplementary sub-synchronous damping controllers (SSDC) are proposed for damping sub-synchronous oscillations in power systems with series compensated transmission lines. Series compensation have extensively been used as effective means of increasing the power transfer capability of a transmission lines and improving transient stability limits of power systems. Series compensation with transmission lines may cause sub-synchronous resonance (SSR). The eigenvalue investigation tool is used to ascertain the existence of SSR. It is shown that the addition of supplementary controller is able to stabilize all unstable modes for T-network model. Eigenvalue investigation and time domain transient simulation of detailed nonlinear system are considered to investigate the performance of the controllers. The efficacies of the suggested supplementary controllers are compared on the IEEE first benchmark model for computer simulations of SSR by means of time domain simulation in Matlab/Simulink environment. Supplementary SSDC are considered in order to compare effectiveness of SSDC during higher loading in alleviating the small signal stability problem.

  14. Modeling particle emission and power flow in pulsed-power driven, nonuniform transmission lines

    Directory of Open Access Journals (Sweden)

    Nichelle Bruner

    2008-04-01

    Full Text Available Pulsed-power driven x-ray radiographic systems are being developed to operate at higher power in an effort to increase source brightness and penetration power. Essential to the design of these systems is a thorough understanding of electron power flow in the transmission line that couples the pulsed-power driver to the load. In this paper, analytic theory and fully relativistic particle-in-cell simulations are used to model power flow in several experimental transmission-line geometries fielded on Sandia National Laboratories’ upgraded Radiographic Integrated Test Stand [IEEE Trans. Plasma Sci. 28, 1653 (2000ITPSBD0093-381310.1109/27.901250]. Good agreement with measured electrical currents is demonstrated on a shot-by-shot basis for simulations which include detailed models accounting for space-charge-limited electron emission, surface heating, and stimulated particle emission. Resonant cavity modes related to the transmission-line impedance transitions are also shown to be excited by electron power flow. These modes can drive oscillations in the output power of the system, degrading radiographic resolution.

  15. Development of Lightning-Resistant Overhead Ground Wire for Large-size Transmission Lines

    Science.gov (United States)

    Taniguchi, Sakae; Nagaraki, Yoshimi; Takami, Jun; Okabe, Shigemitsu; Saito, Toshiyuki; Nagano, Koji; Goda, Yutaka

    The overhead ground wire of AC 150mm2 is applied for the large-size transmission lines. According to inspections of transmission lines, melted component wires of AC 150mm2 have been found in some parts of 500kV transmission lines and it is obvious that the damages have been caused by lightning. Hence, the authors have developed lightning-resistant overhead ground wires as well as being evaluated lightning-resistant performance of the conventional AC 150mm2. In the paper, firstly, it is reported on the lightning performance of the conventional AC 150mm2 resulting from a DC arc test which is considered the polarity of currents and injected current waveforms for summer and winter lightning. As a result, the least amount of electric charges which can melt the components of the conventional wire was 180C. Then, the paper outlines the improvement of lightning performance of the overhead ground wire. Some kinds of developed ground wires as a trial piece have been proposed and tested, and here presented the characteristics of two typical developed wires among them. One is coated with conductive ceramic on the outer components and the another is enlarged a diameter of outer components. Both types of the wires show the excellent lightning performance from the DC arc test, comparing with the conventional ground wire of AC 150mm2.

  16. [Study on effects of bioelectric parameters of rats in electromagnetic radiation of HV transmission line].

    Science.gov (United States)

    Zhang, Anying; Pang, Xiaofeng; Yuan, Ping

    2007-02-01

    With the development of economy and coming of information era, the chance of exposure to electromagnetic fields with various frequencies has been increased for every human. The effects of electromagnetic radiattion on human being's health are versatile. To study the effects of bioelctronic parameters of rats in the electromagnetic radiations of HV transmission line, EEG, ECG and CMAP were measured in rats exposed to simulating high-voltage transmission line electromagnetic radiation for over one year. Brain tissues were studied by Fourier transform infrared spectroscopy. The results showed that no significant difference between exposed group and control group in EEG; however the FT-infrared spectra of brain tissues were different; the ECG of the exposed animals was considerably altered. Significant slowing of heart rate was observed in those rates exposed to EMFs; the latent period of CMAP in exposed group were not different compared with those of control group however there was a significant difference in wave amplitude of CMAP between the exposed group and control group. All results indicated that there must be some effects on bioelectric parameters of rats exposed to electromagnetic radiation of high-voltage transmission line for a long time.

  17. Magnetic fields produced by power lines do not affect growth, serum melatonin, leukocytes and fledging success in wild kestrels.

    Science.gov (United States)

    Dell'Omo, Giacomo; Costantini, David; Lucini, Valeria; Antonucci, Giovanni; Nonno, Romolo; Polichetti, Alessandro

    2009-09-01

    Nesting on high voltage transmission line towers exposes birds to electric and magnetic fields for long periods. Nestlings are exposed from their development in ovo until fledging. This is a critical period for them because the quality of the developmental environment may affect their fitness at adulthood. We carried out a field study on Eurasian kestrels, Falco tinnunculus, to compare chicks from pairs nesting on high voltage power lines vs. those nesting in control sites in similar habitats. The magnetic field (MF) was measured in each nest-box and analysed in relation to growth curves, melatonin levels, leukocyte counts, and fledging success. None of the variables differed between exposed and control nestlings. Wing length (proxy of age) showed a negative covariation with serum melatonin concentration. Our findings suggest that exposure to MFs produced by high voltage power lines during the embryonic and post-hatching period (until fledging) does not have significant short-term physiological effects on kestrel nestlings.

  18. SYNTHESIS OF AN ACTIVE SHIELDING SYSTEM OF THE MAGNETIC FIELD OF POWER LINES BASED ON MULTIOBJECTIVE OPTIMIZATION

    Directory of Open Access Journals (Sweden)

    B. I. Kuznetsov

    2016-12-01

    Full Text Available Purpose. The synthesis of the active shielding systems by technogenic magnetic field generated by the different types of high voltage power lines in a given region of space using various cables of controlled magnetic field sources. Methodology. The initial parameters for the synthesis of active shielding system parameters are the location of the high voltage power lines with respect to the protected transmission line space, geometry and number of cables, operating currents, as well as the size of the protected space and normative value magnetic field induction, which should be achieved as a result of shielding. The objective of the synthesis of the active shielding system is to determine their number, configuration, spatial arrangement, wiring diagrams and compensation cables currents, setting algorithm of the control systems as well as the resulting value of the induction magnetic field at the points of the protected space. Synthesis of active shielding system is reduced to the problem of multiobjective nonlinear programming with constraints in which calculation of the objective functions and constraints are carried out on the basis of Biot – Savart – Laplace law. The problem is solved by a stochastic multi-agent optimization of multiswarm of particles which can significantly reduce the time to solve it. Results. Active screening system synthesis results for the various types of transmission lines and with different amounts of controlled cables is given. The possibility of a significant reduction in the level of induction of the magnetic field source within a given region of space. Originality. For the first time carried out the synthesis of the active shielding systems, by magnetic field generated by the different types of high voltage power lines within a given region of space controlled by a magnetic field sources with different amounts of controlled cables. Practical value, Practical recommendations on reasonable choice of the number

  19. Study of the behaviour of chaotic magnetic field lines in a tokamak

    International Nuclear Information System (INIS)

    Hugon, M.; Mendonca, J.T.; Rebut, P.H.

    1989-01-01

    One plausible explanation for the observed anomalous energy losses in tokamaks is the existence of a confinement region in the plasma, where magnetic islands coexist with stochastic magnetic field lines. It is the purpose of the present work to elucidate the statistical behaviour of the stochastic field lines. This is done by numerically integrating the field line equations. (author) 4 refs., 2 figs

  20. Application of computational dosimetry studies to assess electromagnetic fields exposure in the vicinity of transmission lines and power substations

    International Nuclear Information System (INIS)

    Domingues, Luis A.M.C.; Cruz, Rafael M.; Neto, Athanasio Mpalatinos; Barbosa, Carlos R. Nunez

    2008-01-01

    Full text: This paper presents a methodological approach to assess exposure to ELF EMF's from transmission lines (TL's) and power substations (SE's), in order to verify their compliance to International Standards, such as ICNIRP and IEEE. In order to calculate the fields/currents induced inside the body which are used to verify compliance to the basic restrictions established on those Standards, a chain of calculation tools is established, in order to: Determine electric and magnetic fields produced by transmission lines/substations (magnitudes and phase angles at every point in space surrounding the installation); Establish an accurate model (FEM/FDM) for an human body submitted to the EMFs; Assign electric (permittivity and conductivity) characteristics to body tissues. A specific research intended to measure those parameters on living body tissues is mentioned, as an alternative to the general use of values found on the literature based on measurements made on dead bodies; Use the above calculation tools in order to determine the fields and currents induced inside bodies, by the applied external fields, at each point in space, for both general public and occupational exposure situations. Finally an application of this methodology to a practical case where the construction of an Urban Power Substation was under analysis on Public Hearings is presented. The analysis of the original design concept, as well as the proposed design improvements, intended to lower public exposure to EMF's are presented. The case of occupational exposure concerning workers on live line conditions is also analysed, and alternatives to reduce exposure on this case are proposed. (author)

  1. Advanced Design of the First Quasi-optical Transmission Line for ECRH at TJ-II

    International Nuclear Information System (INIS)

    Fernandez, A.; Likin, K.; Martin, R.

    1999-01-01

    TJ-II plasma start-up and heating are made by electron cyclotron resonance waves at the second harmonic of the electron cyclotron frequency. The microwave power of the gyrotrons is transmitted by two quasi-optical transmission lines. The first line launches the microwave power under fixed injection geometry, i. e. there is no a possibility to change the launching angle the wave polarization. Due to the long distance between the last focusing mirror and the center TJ-II vessel the beam is quite wide at plasma border. The second line has a moveable mirror installed inside the TJ-II vessel. To get high absorption efficiency and a narrow energy deposition profile the internal mirror focuses the wave beam at plasma center. The beam width is about 2 cm. To get more flexibility in experiments on heating and current drive the first transmission line needs to be upgraded. The designs is presented in this report. It includes and internal mirror to focus the beam and to change the injection angle. A polarizer consisting in two corrugated mirrors will be incorporated to get any wave polarization. Two mirrors with an array of coupling holes and calorimetric measurements of the energy absorbed in the barrier window will permit the estimation of the microwave power launched the TJ-II. (Author) 13 refs

  2. Wilson lines and UV sensitivity in magnetic compactifications

    Science.gov (United States)

    Ghilencea, D. M.; Lee, Hyun Min

    2017-06-01

    We investigate the ultraviolet (UV) behaviour of 6D N=1 supersymmetric effective (Abelian) gauge theories compactified on a two-torus ( T 2) with magnetic flux. To this purpose we compute offshell the one-loop correction to the Wilson line state self-energy. The offshell calculation is actually necessary to capture the usual effective field theory expansion in powers of (∂ /Λ). Particular care is paid to the regularization of the (divergent) momentum integrals, which is relevant for identifying the corresponding counterterm(s). We find a counterterm which is a new higher dimensional effective operator of dimension d=6, that is enhanced for a larger compactification area (where the effective theory applies) and is consistent with the symmetries of the theory. Its consequences are briefly discussed and comparison is made with orbifold compactifications without flux.

  3. Distance protection of multiple-circuit shared tower transmission lines with different voltages

    DEFF Research Database (Denmark)

    Silva, Filipe Miguel Faria da; Bak, Claus Leth

    2017-01-01

    Multiple-circuit transmission lines combining different voltage levels in one tower present extra challenges when setting a protection philosophy, as faults between voltage levels are possible. In this study, the fault loop impedance of combined faults is compared with the fault loop impedance......-phase-to-ground faults. It is also demonstrated that the fault loop impedance of combined faults is more resistive, when compared with equivalent single-phase-to-ground faults. It is concluded that the settings used to protect a line against single-phase-to-ground faults are capable of protecting the line against...... combined faults, being advised to increase the resistive limit of the protection zone, if the network has lower short-circuit power. It is recommended to assure that the fault can only happen for cases where the faulted phase from the higher voltage level leads the faulted phase from the lower voltage...

  4. Accurate fault location algorithm on power transmission lines with use of two-end unsynchronized measurements

    Directory of Open Access Journals (Sweden)

    Mohamed Dine

    2012-01-01

    Full Text Available This paper presents a new approach to fault location on power transmission lines. This approach uses two-end unsynchronised measurements of the line and benefits from the advantages of digital technology and numerical relaying, which are available today and can easily be applied for off-line analysis. The approach is to modify the apparent impedance method using a very simple first-order formula. The new method is independent of fault resistance, source impedances and pre-fault currents. In addition, the data volume communicated between relays is sufficiently small enough to be transmitted easily using a digital protection channel. The proposed approach is tested via digital simulation using MATLand the applied test results corroborate the superior performance of the proposed approach.

  5. CRPP's Evacuated Waveguide Proposal for JET-EP ECRH Transmission Line

    International Nuclear Information System (INIS)

    Henderson, M. A.; Alberti, S.; Goodman, T. P.; Hogge, J.-P.; Porte, L.; Tran, M. Q.

    2002-01-01

    The goal of this document is to provide a detailed description of the preliminary design and technical information of a proposed evacuated transmission lines for JET . EP ECRH system. Three waveguide diameters (31.75mm, 45mm and 63.5mm) were studied and compared to the base design of the 87mm waveguide/quasi.optical proposal (WG87-QO). This report concentrates on only the 45mm waveguide diameter (WG45). This size represents an optimization between the flexibility of the smaller diameter and the low loss of the larger. For simplicity only the WG45 will be compared with the WG87-QO, but the other diameters (31.75 and 63.5 mm) should be kept under consideration for a final evacuated waveguide line. The characteristics of the 63.5 mm waveguide system can be found in the report which was distributed in September. After an introduction of the history and motivation for this study a general overview of the proposal is presented. Sections 4 and 5 describe the elements to be used in the proposed line including the overall transmission losses for the line. Section 6 offers a cost comparison of the two proposaIs. The 7th section is a brief description of an alternative launcher design using the waveguide inserted into the launcher port. The 8th section describes the ca1ibration and conditioning process to be performed after the line is insta1led and how the torus displacements wi1l be handled. The 9th section describes the proposed schedule for purchasing and insta1lation of the waveguide lines. Sections II and 12 include a conclusion and summary of the proposal. (author)

  6. Flatiron-Erie 115kV transmission line project, Larimer, Weld and Boulder Counties, Colorado

    International Nuclear Information System (INIS)

    1993-05-01

    Western Area Power Administration (Western) proposes to uprate its existing 115-kV Flatiron-Erie transmission line. The line is located in Larimer, Weld and Boulder Counties, Colorado, and passes through the City of Longmont. The line connects Flatiron Substation and several of the substations supplying Longmont. It is a single circuit 115-kV line, 31.5 miles long, and was built in 1950-51 on a 75-foot wide right-of-way (ROW) using wood H-frame structures. Western proposes to build 27 new structures along the line, to replace or modify 45 of the existing structures and to remote 11 of them. Many of these additions and changes would involve structures that are approximately 5 to 15 feet taller than the existing ones. The existing conductors and ground wires would remain in place. The purpose of these actions would be to allow the power carrying capability of the line to be increased and to replace deteriorating/structural members. Western would be the sole participant in the proposed project. This report gives an analysis of the study area environment and the development of alternative routes. An assessment is presented of the impacts of the primary alternative routes. The environmental consequences of this project are addressed

  7. Inclusion of the frequency effect in the lumped parameters transmission line model: State space formulation

    Energy Technology Data Exchange (ETDEWEB)

    Kurokawa, Sergio; Yamanaka, Fabio N.R.; Prado, Afonso J. [Faculdade de Engenharia de Ilha Solteira, Avenida Brasil Centro 56, Caixa Postal 31, Ilha Solteira, SP, CEP 15385-000 (Brazil); Pissolato, Jose [Universidade Estadual de Campinas, Caixa Postal 6101, CEP 13081-970, Campinas, SP (Brazil)

    2009-07-15

    The objective of this paper is to include the frequency dependence of the longitudinal parameters in the lumped parameters line model. The distributed nature of the transmission line was approximated by a cascade of {pi} circuits and the frequency effect was approximated by a rational function which was synthesized by an equivalent circuit. Then, the equivalent circuit was inserted in each {pi} circuit of the cascade. After that, the currents and voltages along the line were described in the form of state equations. This way, it was possible to obtain a formation rule of the state matrices lumped parameters model taking into account the frequency dependence. To confirm the validation of the state matrices obtained, the lumped parameters representation of frequency-dependent lines was used to represent a single-phase line and a three-phase line. The simulations were carried out using state space techniques and an electromagnetic transient program (EMTP) (in this case, the cascade was inserted in the EMTP). It is observed that the simulation results obtained with state space representation are in agreement with those results obtained with EMTP. (author)

  8. Association between exposure to electromagnetic fields from high voltage transmission lines and neurobehavioral function in children.

    Directory of Open Access Journals (Sweden)

    Jiongli Huang

    Full Text Available BACKGROUND: Evidence for a possible causal relationship between exposure to electromagnetic fields (EMF emitted by high voltage transmission (HVT lines and neurobehavioral dysfunction in children is insufficient. The present study aims to investigate the association between EMF exposure from HVT lines and neurobehavioral function in children. METHODS: Two primary schools were chosen based on monitoring data of ambient electromagnetic radiation. A cross-sectional study with 437 children (9 to 13 years old was conducted. Exposure to EMF from HVT lines was monitored at each school. Information was collected on possible confounders and relevant exposure predictors using standardized questionnaires. Neurobehavioral function in children was evaluated using established computerized neurobehavioral tests. Data was analyzed using multivariable regression models adjusted for relevant confounders. RESULTS: After controlling for potential confounding factors, multivariable regression revealed that children attending a school near 500 kV HVT lines had poorer performance on the computerized neurobehavioral tests for Visual Retention and Pursuit Aiming compared to children attending a school that was not in close proximity to HVT lines. CONCLUSIONS: The results suggest long-term low-level exposure to EMF from HVT lines might have a negative impact on neurobehavioral function in children. However, because of differences in results only for two of four tests achieved statistical significance and potential limitations, more studies are needed to explore the effects of exposure to extremely low frequency EMF on neurobehavioral function and development in children.

  9. Association between exposure to electromagnetic fields from high voltage transmission lines and neurobehavioral function in children.

    Science.gov (United States)

    Huang, Jiongli; Tang, Tiantong; Hu, Guocheng; Zheng, Jing; Wang, Yuyu; Wang, Qiang; Su, Jing; Zou, Yunfeng; Peng, Xiaowu

    2013-01-01

    Evidence for a possible causal relationship between exposure to electromagnetic fields (EMF) emitted by high voltage transmission (HVT) lines and neurobehavioral dysfunction in children is insufficient. The present study aims to investigate the association between EMF exposure from HVT lines and neurobehavioral function in children. Two primary schools were chosen based on monitoring data of ambient electromagnetic radiation. A cross-sectional study with 437 children (9 to 13 years old) was conducted. Exposure to EMF from HVT lines was monitored at each school. Information was collected on possible confounders and relevant exposure predictors using standardized questionnaires. Neurobehavioral function in children was evaluated using established computerized neurobehavioral tests. Data was analyzed using multivariable regression models adjusted for relevant confounders. After controlling for potential confounding factors, multivariable regression revealed that children attending a school near 500 kV HVT lines had poorer performance on the computerized neurobehavioral tests for Visual Retention and Pursuit Aiming compared to children attending a school that was not in close proximity to HVT lines. The results suggest long-term low-level exposure to EMF from HVT lines might have a negative impact on neurobehavioral function in children. However, because of differences in results only for two of four tests achieved statistical significance and potential limitations, more studies are needed to explore the effects of exposure to extremely low frequency EMF on neurobehavioral function and development in children.

  10. On field line resonances of hydromagnetic Alfven waves in dipole magnetic field

    International Nuclear Information System (INIS)

    Chen, Liu; Cowley, S.C.

    1989-07-01

    Using the dipole magnetic field model, we have developed the theory of field line resonances of hydromagnetic Alfven waves in general magnetic field geometries. In this model, the Alfven speed thus varies both perpendicular and parallel to the magnetic field. Specifically, it is found that field line resonances do persist in the dipole model. The corresponding singular solutions near the resonant field lines as well as the natural definition of standing shear Alfven eigenfunctions have also been systematically derived. 11 refs

  11. Seismic Response of Power Transmission Tower-Line System Subjected to Spatially Varying Ground Motions

    Directory of Open Access Journals (Sweden)

    Li Tian

    2010-01-01

    Full Text Available The behavior of power transmission tower-line system subjected to spatially varying base excitations is studied in this paper. The transmission towers are modeled by beam elements while the transmission lines are modeled by cable elements that account for the nonlinear geometry of the cables. The real multistation data from SMART-1 are used to analyze the system response subjected to spatially varying ground motions. The seismic input waves for vertical and horizontal ground motions are also generated based on the Code for Design of Seismic of Electrical Installations. Both the incoherency of seismic waves and wave travel effects are accounted for. The nonlinear time history analytical method is used in the analysis. The effects of boundary conditions, ground motion spatial variations, the incident angle of the seismic wave, coherency loss, and wave travel on the system are investigated. The results show that the uniform ground motion at all supports of system does not provide the most critical case for the response calculations.

  12. Mode and climatic factors effect on energy losses in transient heat modes of transmission lines

    Science.gov (United States)

    Bigun, A. Ya; Sidorov, O. A.; Osipov, D. S.; Girshin, S. S.; Goryunov, V. N.; Petrova, E. V.

    2018-01-01

    Electrical energy losses increase in modern grids. The losses are connected with an increase in consumption. Existing models of electric power losses estimation considering climatic factors do not allow estimating the cable temperature in real time. Considering weather and mode factors in real time allows to meet effectively and safely the consumer’s needs to minimize energy losses during transmission, to use electric power equipment effectively. These factors increase an interest in the evaluation of the dynamic thermal mode of overhead transmission lines conductors. The article discusses an approximate analytic solution of the heat balance equation in the transient operation mode of overhead lines based on the least squares method. The accuracy of the results obtained is comparable with the results of solving the heat balance equation of transient thermal mode with the Runge-Kutt method. The analysis of mode and climatic factors effect on the cable temperature in a dynamic thermal mode is presented. The calculation of the maximum permissible current for variation of weather conditions is made. The average electric energy losses during the transient process are calculated with the change of wind, air temperature and solar radiation. The parameters having the greatest effect on the transmission capacity are identified.

  13. The performance of transmission lines and cables subjected to electromagnetic radiation from a nuclear explosion (NEMP)

    International Nuclear Information System (INIS)

    Aguet, M.; Ianovici, M.; Lin, C.C.; Fornerod, F.

    1980-01-01

    The use of armoured cables for telecommunication and data transmission systems is practically essential to avoid electromagnetic interference. The authors have made a mathematical study of the probable effect of a high altitude nuclear explosion. Using a simplified model, the voltages and currents induced into single and multiple-sheathed, overhead and buried cables subjected to an intense magnetic pulse (50kV/m) from high altitude, are determined by computer. It is found that, contrary to expectations the current intensity in the second case is seven times greater than for the overhead conductor. (F.N.S.)

  14. Ap stars with resolved magnetically split lines: Magnetic field determinations from Stokes I and V spectra⋆

    Science.gov (United States)

    Mathys, G.

    2017-05-01

    Context. Some Ap stars that have a strong enough magnetic field and a sufficiently low v sini show spectral lines resolved into their magnetically split components. Aims: We present the results of a systematic study of the magnetic fields and other properties of those stars. Methods: This study is based on 271 new measurements of the mean magnetic field modulus ⟨ B ⟩ of 43 stars, 231 determinations of the mean longitudinal magnetic field ⟨ Bz ⟩ and of the crossover ⟨ Xz ⟩ of 34 stars, and 229 determinations of the mean quadratic magnetic field ⟨ Bq ⟩ of 33 stars. Those data were used to derive new values or meaningful lower limits of the rotation periods Prot of 21 stars. Variation curves of the mean field modulus were characterised for 25 stars, the variations of the longitudinal field were characterised for 16 stars, and the variations of the crossover and of the quadratic field were characterised for 8 stars. Our data are complemented by magnetic measurements from the literature for 41 additional stars with magnetically resolved lines. Phase coverage is sufficient to define the curve of variation of ⟨ B ⟩ for 2 of these stars. Published data were also used to characterise the ⟨ Bz ⟩ curves of variation for 10 more stars. Furthermore, we present 1297 radial velocity measurements of the 43 Ap stars in our sample that have magnetically resolved lines. Nine of these stars are spectroscopic binaries for which new orbital elements were derived. Results: The existence of a cut-off at the low end of the distribution of the phase-averaged mean magnetic field moduli ⟨ B ⟩ av of the Ap stars with resolved magnetically split lines, at about 2.8 kG, is confirmed. This reflects the probable existence of a gap in the distribution of the magnetic field strengths in slowly rotating Ap stars, below which there is a separate population of stars with fields weaker than 2 kG. In more than half of the stars with magnetically resolved lines that have a

  15. Rotor for a line start permanent magnet machine

    Science.gov (United States)

    Melfi, Mike; Schiferl, Rich; Umans, Stephen

    2017-07-11

    A rotor comprises laminations with a plurality of rotor bar slots with an asymmetric arrangement about the rotor. The laminations also have magnet slots equiangularly spaced about the rotor. The magnet slots extend near to the rotor outer diameter and have permanent magnets disposed in the magnet slots creating magnetic poles. The magnet slots may be formed longer than the permanent magnets disposed in the magnets slots and define one or more magnet slot apertures. The permanent magnets define a number of poles and a pole pitch. The rotor bar slots are spaced from adjacent magnet slots by a distance that is at least 4% of the pole pitch. Conductive material is disposed in the rotor bar slots, and in some embodiments, may be disposed in the magnet slot apertures.

  16. Anisotropic behaviour of transmission through thin superconducting NbN film in parallel magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Šindler, M., E-mail: sindler@fzu.cz [Institute of Physics ASCR, v. v. i., Cukrovarnická 10, CZ-162 53 Praha 6 (Czech Republic); Tesař, R. [Institute of Physics ASCR, v. v. i., Cukrovarnická 10, CZ-162 53 Praha 6 (Czech Republic); Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, CZ-121 16 Praha (Czech Republic); Koláček, J. [Institute of Physics ASCR, v. v. i., Cukrovarnická 10, CZ-162 53 Praha 6 (Czech Republic); Skrbek, L. [Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, CZ-121 16 Praha (Czech Republic)

    2017-02-15

    Highlights: • Transmission through thin NbN film in parallel magnetic field exhibits strong anisotropic behaviour in the terahertz range. • Response for a polarisation parallel with the applied field is given as weighted sum of superconducting and normal state contributions. • Effective medium approach fails to describe response for linear polarisation perpendicular to the applied magnetic field. - Abstract: Transmission of terahertz waves through a thin layer of the superconductor NbN deposited on an anisotropic R-cut sapphire substrate is studied as a function of temperature in a magnetic field oriented parallel with the sample. A significant difference is found between transmitted intensities of beams linearly polarised parallel with and perpendicular to the direction of applied magnetic field.

  17. Determination index of compatible vegetable species with the lines of electric power transmission

    International Nuclear Information System (INIS)

    Jimenez G, Yulie Andrea; Serna G, Marcela; Lema T, Alvaro; Alvarez D, Esteban; Rincon H, Hernan; Cogollo P, Alvaro

    2004-01-01

    With the purpose of designing methods to clearly identify which plant species generate electrical ground discharges in energy transmission line service corridors and thus avoid the frequent pruning of all Vegetation present in the corridors this study proposes and evaluates compatibility index of plant species with transmission lines, based on six variables: maximum height, growth form, ecological group, life zone, and abundance and frequency of each species. This index was tested in 20 plots of information was collected on all vascular plans present yielding 2147 individuals belonging to 485 species and 105 families, the most discriminating variables in the model were life zone and ecological group, based upon an analysis of principal components. This index applied to the 147 fully identified species with DBH = 2,5 cm showed that Cecropia peltata and Jacaranda copaia were the most problematic species for service lines. Furthermore, a catalogue was developed containing general information and a photographic record of some of the species considered as compatible as a reference for use during maintenance work

  18. Inductance calculation of submarine DC transmission line based on finite element analysis

    Directory of Open Access Journals (Sweden)

    WANG Qi

    2018-02-01

    Full Text Available [Objectives] Because of the characteristics of submarine direct current (DC transmission cables, traditional circuit inductance calculation methods are unable to fit the system. There is a big error between the calculating value and the actual value. This paper studies the finite element method to reduce the calculation error. [Methods] The applicability of common line inductance calculation formulas to submarine DC system is discussed firstly. Then a short-circuit testing system is set up. The inductance of circuit in the system is measured, and a simulation model of the testing system is established. For a comparing purpose, the total inductance of the line is calculated by finite element analysis in the ANSYS/Maxwell software too. With the inductance values, the equivalent circuit model of the testing system is simulated in the Matlab/Simulink software. The simulation waveforms of the short-circuit current and the measured waveform are analyzed and compared. [Results] The result shows that the finite element analysis method is able to improve the accuracy of calculation of submarine DC transmission line equivalent inductance, and reduce the error in DC power system transient analysis. [Conclusions] The achievement can provide support for further simulation model development and calculation method research.

  19. Transmission-line resonators for the study of individual two-level tunneling systems

    Science.gov (United States)

    Brehm, Jan David; Bilmes, Alexander; Weiss, Georg; Ustinov, Alexey V.; Lisenfeld, Jürgen

    2017-09-01

    Parasitic two-level tunneling systems (TLS) emerge in amorphous dielectrics and constitute a serious nuisance for various microfabricated devices, where they act as a source of noise and decoherence. Here, we demonstrate a new test bed for the study of TLS in various materials which provides access to properties of individual TLS as well as their ensemble response. We terminate a superconducting transmission-line resonator with a capacitor that hosts TLS in its dielectric. By tuning TLS via applied mechanical strain, we observe the signatures of individual TLS strongly coupled to the resonator in its transmission characteristics and extract the coupling components of their dipole moments and energy relaxation rates. The strong and well-defined coupling to the TLS bath results in pronounced resonator frequency fluctuations and excess phase noise, through which we can study TLS ensemble effects such as spectral diffusion, and probe theoretical models of TLS interactions.

  20. Improved superconductor for transmission line applications, phase I. Final report, January 1, 1975--June 30, 1975

    International Nuclear Information System (INIS)

    Braginski, A.I.; Mauser, S.F.; Roland, G.W.; Burghardt, R.R.; Daniel, M.R.; Janocko, M.A.

    1975-01-01

    The analysis of an existing superconducting power transmission cable design indicated that economic benefits in the area of refrigeration can be derived from the substitution of Nb 3 Ge superconductor for the presently planned Nb 3 Sn. However, the cost of Nb 3 Ge must be comparable to that of Nb 3 Sn, which is achievable when preparing Nb 3 Ge by the chemical vapor deposition. Alternatively, technical benefits can be obtained. The most essential and prerequisite requirement is that the Nb 3 Ge critical current density be improved significantly over the present state-of-the art. Other properties of Nb 3 Ge are generally suitable for the transmission line application and/or require only moderate improvements. (auth)

  1. Estimation for the performance of superconducting DC transmission lines with cryogenics improvements

    Energy Technology Data Exchange (ETDEWEB)

    Kawahara, Toshio, E-mail: toshi@isc.chubu.ac.j [Center of Applied Superconductivity and Sustainable Energy Research, Chubu University, Aichi 487-8501 (Japan); Fujii, Tomohiro [Department of Electrical Engineering, Chubu University, Aichi 487-8501 (Japan); Emoto, Masahiko [National Institute for Fusion Science, Gifu 509-5292 (Japan); Hamabe, Makoto; Sun, Jian; Watanabe, Hirofumi [Center of Applied Superconductivity and Sustainable Energy Research, Chubu University, Aichi 487-8501 (Japan); Yamaguchi, Satarou [Center of Applied Superconductivity and Sustainable Energy Research, Chubu University, Aichi 487-8501 (Japan); Department of Electrical Engineering, Chubu University, Aichi 487-8501 (Japan)

    2010-12-15

    Recent energy saving and environmental protection highly demand the development of new technology such as superconducting applications. At Chubu University, we have developed direct current (DC) superconducting 20 m transmission lines as a working trial system for the actual applications. Our parameter is promising for long distance transmission with low pump power. On the other hand, superconducting DC distribution is also useful in green internet technology such as the energy saving in the internet data center. However, such short length superconducting applications require special thermal designs because the heat leak into the system is comparably larger than the energy reduction in superconducting cables. From the viewpoint of cryogenics, high performance current lead is in high demand such as the Peltier current lead (PCL). With the improvements of current leads, we can reduce the heat leak to reach the very low loss systems required for the small superconducting application systems as the cost-effective ones.

  2. Textile artificial magnetic conductor jacket for transmission enhancement between antennas under bending and wetness measurements

    Science.gov (United States)

    Kamardin, Kamilia; Rahim, Mohamad Kamal A.; Hall, Peter S.; Samsuri, Noor Asmawati; Latef, Tarik Abdul; Ullah, Mohammad Habib

    2016-04-01

    Textile artificial magnetic conductor (AMC) waveguide jacket for transmission enhancement between on-body antennas is proposed. Transmission characteristics between antennas with different orientations and placements are studied. Significant transmission enhancement is observed for all tested positions. Bending and wetness measurements are also conducted. Bending is found not to give significant effect to the antennas and AMC performance, while wetness yields severe performance distortion. However, the original performance is retrieved once the antennas and AMC dried. The proposed AMC jacket will act as a new approach for efficient wearable body-centric communications.

  3. Anisotropic behaviour of transmission through thin superconducting NbN film in parallel magnetic field

    Czech Academy of Sciences Publication Activity Database

    Šindler, Michal; Tesař, Karel; Koláček, Jan; Skrbek, L.

    2017-01-01

    Roč. 533, Feb (2017), s. 154-157 ISSN 0921-4534 R&D Projects: GA MŠk(CZ) LD14060 Institutional support: RVO:68378271 Keywords : far-infrared transmission * NbN * ssuperconducting film * vortices * terahertz waves * parallel magnetic field Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 1.404, year: 2016

  4. Underwater spark discharge with long transmission line for cleaning horizontal wells

    Science.gov (United States)

    Lee, Kern; Chung, Kyoung-Jae; Hwang, Y. S.; Kim, C. Y.

    2017-06-01

    A transmission line is discussed for application in an underwater spark-discharge technique in the cleaning of a horizontal well by incorporating a power-transmission model into the simulation. The pulsed-spark-discharge technique has been proposed for clogged-well rehabilitation, because it removes incrustations that are attached to well screens by using strong pressure waves that are generated by the rapid expansion of a spark channel. To apply the pulsed-spark-discharge technique to the cleaning of horizontal wells, the coaxial cable between the pulsed power supply and the spark gap as a load needs to be extended to a few hundred meters. Prior to field application, pulsed-spark-discharge experiments were conducted and the role of the transmission line was examined using an improved simulation model. In the model, a non-linear interaction of the spark channel and the capacitor bank is described by the pulse-forming action of the coaxial cable. Based on the accurate physical properties of the water plasma, such as the equation of state and electrical conductivity within the region of interest, the amount of energy contributed to the development of a shock wave was evaluated. The simulation shows that if the initial conditions of the spark channel are the same, no further reduction in strength of the pressure wave occurs, even if the cable length is increased above 50 m. Hence, the degraded peak pressure that was observed in the experiments using the longer cable is attributed to a change in the initial condition of the spark channel. The parametric study suggests that the low initial charging voltage, the high ambient water pressure, and the long cable length yield the low initial spark-channel density, which results in a reduced peak pressure. The simulation of line charging is presented to discuss the principle of disturbing the pre-breakdown process by an extended cable.

  5. Final environmental assessment: Los Reales 115 kV transmission line alternative routes

    Energy Technology Data Exchange (ETDEWEB)

    1989-10-01

    The Central Arizona Project (CAP) was authorized as a part of the Colorado River Basin Project Act (Public Law 90-537) on September 30, 1968. The primary purpose of the CAP is to furnish water for agricultural, municipal, and industrial uses in central and southern Arizona, and western New Mexico. Due to its magnitude, the CAP is divided into several major features serving separate but interrelated functions. The Tucson Aqueduct Phase B pumping plants were designed and constructed to operate on a looped power system. The entire looped power system, including two switching stations and connecting 115-kv transmission lines, was identified in the FEIS and approved for construction in the Secretary of Interior's Record of Decision dated September 24, 1985. The loop begins in the vicinity of the Twin Peaks Pumping Plant -- the northernmost Phase B pumping station, at the Rattlesnake Switching Station. All of the looped power system has been constructed with the exception of the switching station and portion of transmission line proposed to be constructed in this project. Without construction of this final portion of the looped power system, the Phase B pumping plants will not be able to operate normally without negatively affecting nearby power sources. The CAP will also not be able to provide the reliability necessary for municipal water systems dependent upon CAP water. The purpose of this EA is to describe impacts that would result from relocating the Los Reales 115-kV transmission line, and possibly the switching station, originally identified in the FEIS. It should be mentioned the Department of Energy will complete a separate NEPA review.

  6. Numerical study of electron-leakage power loss in a tri-plate transmission line

    International Nuclear Information System (INIS)

    Barker, R.J.; Goldstein, S.A.

    1982-01-01

    Numerical simulations have been conducted using NRL's DIODE2D computer code to model the steady-state behavior of electron flow in a radial diode and in its adjacent tri-plate transmission line (TTL). Particular attention was paid to the magnitude of the electron current flowing from the cathode to the anode surface in the TTL. A quantitative value for this effective power loss is given. The electron current is restricted mainly to the transition region in the TTL into which there is seepage of the B/sub z/ that is imposed in the diode gap. This finding highlights the importance of that region to diode designers

  7. A High Resolution Digital Phase Shifter using Distributed MEMS Transmission Lines-A New Approach

    Science.gov (United States)

    Jose K, Nisha; Baiju, M. R.

    2017-12-01

    Distributed Micro Electromechanical systems Transmission Line (DMTL) is used for designing digital phase shifters, by using an array of shunt switches. In the present paper, a new approach for designing DMTL for small phase steps is proposed. In the present work, an additional single switch section is introduced, having half the phase shift as the other switch sections in the DMTL. The addition of the new switch section does not alter the characteristic impedance or total phase shift of the DMTL phase shifter. A high resolution phase shifter is designed using the proposed model and the simulation results are presented. The proposed method can be further extended for achieving smaller phase steps.

  8. Charge transport across a single-Cooper-pair transistor coupled to a resonant transmission line

    Energy Technology Data Exchange (ETDEWEB)

    Leppaekangas, Juha [Institut fuer Theoretische Festkoerperphysik, Karlsruhe Institute of Technology, D-76128 Karlsruhe (Germany); Department of Physical Sciences, University of Oulu, FI-90014 Oulu (Finland); Pashkin, Yuri [NEC Nano Electronics Research Laboratories, RIKEN Advanced Science Institute, Tsukuba, Ibaraki 305-8501 (Japan); Thuneberg, Erkki [Department of Physical Sciences, University of Oulu, FI-90014 Oulu (Finland)

    2010-07-01

    We have investigated charge transport in ultrasmall superconducting single and double Josephson junctions coupled to a transmission-line resonator. The microstrip resonator is naturally formed by the on-chip leads and the sample holder. We observe equidistant peaks in the transport characteristics of both types of devices and attribute them to the process involving simultaneous tunneling of Cooper pairs and photon emission into the resonator. The experimental data is well reproduced with the orthodox model of Cooper pair tunneling that accounts for the microwave photon emission into the resonator.

  9. Electromagnetic Field Interaction With Transmission Lines From Classical Theory to HF Radiation Effects

    CERN Document Server

    Tkachenko, Sergey V

    2008-01-01

    The evaluation of the electromagnetic field coupling to transmission lines is an important problem in electromagnetic compatibility. The unabated increase in the operating frequency of electronic products and the emergence of sources of disturbances with higher frequency content (such as High Power Microwave and Ultra-Wide Band systems) have led to a breakdown of the TL approximation's basic assumptions for a number of applications. In the last decade or so, the generalization of the TL theory to take into account high frequency effects has emerged as an important topic of study in electromagn

  10. Direct measurement of the quantum state of the electromagnetic field in a superconducting transmission line

    International Nuclear Information System (INIS)

    Melo, F. de; Aolita, L.; Davidovich, L.; Toscano, F.

    2006-01-01

    We propose an experimental procedure to directly measure the state of an electromagnetic field inside a resonator, corresponding to a superconducting transmission line, coupled to a Cooper-pair box (CPB). The measurement protocol is based on the use of a dispersive interaction between the field and the CPB, and the coupling to an external classical field that is tuned to resonance with either the field or the CPB. We present a numerical simulation that demonstrates the feasibility of this protocol, which is within reach of present technology

  11. Assessment of Lightning Shielding Performance of a 400 kV Double-Circuit Fully Composite Transmission Line Pylon

    DEFF Research Database (Denmark)

    Jahangiri, Tohid; Bak, Claus Leth; Silva, Filipe Miguel Faria da

    2016-01-01

    Modern day overhead transmission lines are taking a giant leap in modernization, with the change in power generation from fossil fuels to renewable sources such as solar power, hydro power and wind power. The renewable generation needs to be connected to a large scale high voltage transmission grid....... In Europe alone, 28.000 km of 400 kV transmission line is needed by 2020 to fulfil the aim of providing 20% of Europe’s energy from green energies. It means that more than 100.000 new pylons will be needed [1]. For this reason, the next generation of overhead line is introduced, by developing new design...... pylons that are easier to erect, less costly, smaller and environmentally more feasible than the old ones, which is important to get public acceptance. In this regard, a fully composite pylon for 400 kV overhead transmission lines is presented with a new innovative design concept shown in Figure 1...

  12. RKKY interaction between extended magnetic defect lines in graphene

    DEFF Research Database (Denmark)

    Gorman, P. D.; Duffy, J. M.; Power, Stephen

    2014-01-01

    Of fundamental interest in the field of spintronics is the mechanism of indirect exchange coupling between magnetic impurities embedded in metallic hosts. A range of physical features, such as magnetotransport and overall magnetic moment formation, are predicated upon this magnetic coupling, ofte...... consequences for the spintronic application of magnetically-doped systems, and we illustrate this with a simple magnetoresistance device....

  13. A Miniaturized 4 : 1 Unequal Wilkinson Power Divider Using Artificial Transmission Lines and Double-Sided Parallel-Strip Lines

    Directory of Open Access Journals (Sweden)

    Wen Huang

    2017-01-01

    Full Text Available A 4 : 1 unequal Wilkinson power divider using microstrip artificial transmission lines (ATLs is proposed. For the ATL, a series of meandered-line inductors, parallel-plate capacitors, and interdigital capacitors are employed. The designed power divider is composed of three ATLs, and a method has been proposed using technology of ATLs and double-sided parallel-strip lines (DSPSLs to design line of high characteristic impedance. Microstrip line with very high characteristic impedance of over 150 Ω has been achieved by this method, which cannot be easily achieved by conventional transmission lines because of comparably thin conductor width. The fabricated 4 : 1 unequal power divider has good operational performance and occupies 55.3 mm×37.8 mm, which is only about 40% of area compared to a conventional one at 0.9 GHz.

  14. Summit-Watertown transmission line project, South Dakota. Final Environmental Assessment

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-01

    The Western Area Power Administration (Western) needs to rebuild the existing Summit-Watertown 115-kV transmission line, located in northeastern South Dakota, and western Minnesota. Nearly 60 percent of the existing facility was replaced in 1965 after severe ice-loading broke structures and wires. Because of the extensive loss of the line, surplus poles had to be used to replace the damaged H-frame structures. These were of varying sizes, causing improper structure loading. Additionally, the conductors and overhead shield wires have been spliced in numerous places. This provides additional space on these wires for icing and wind resistance, which in turn create problems for reliability. Finally, a progressive fungal condition has weakened the poles and, along with the improper loading, has created an unsafe condition for maintenance personnel and the general public.

  15. Earth conductivity and permittivity data measurements: Influence in transmission line transient performance

    Energy Technology Data Exchange (ETDEWEB)

    Portela, C.M. [COPPE, Federal University of Rio de Janeiro, Rua Eng. Cesar Grillo 249, 22640-150 Rio de Janeiro, RJ (Brazil); Gertrudes, J.B.; Tavares, M.C.; Pissolato, J. [School of Electrical and Computing Engineering, University of Campinas, PO Box 6101, 13083-970 Campinas, SP (Brazil)

    2006-07-15

    In this work some procedures to measure and model soil electromagnetic behavior in frequency domain are presented. The soil samples were collected at Cachoeira Paulista, Brazil, southeastern region (22{sup o}41.2'S, 44{sup o}59.0'W). The proposed model takes into account the earth conductivity and permittivity frequency dependence. Some procedures to reduce noise signals in the field measurement values are presented. The parameters of an actual 440kV single three-phase transmission line were evaluated in frequency domain (considering the proposed soil model and the common representation with a constant conductivity and no permittivity), such as longitudinal line parameters, attenuation factor, phase velocity and transfer function. It was possible to identify regions where not considering the proposed model could result in severe error. (author)

  16. Elements of the dynamic behaviour of a 2-metre straw tracker : straw as transmission line

    CERN Document Server

    Wertelaers, P

    2010-01-01

    This Note reports on computational work only. A straw has to be treated as a transmission line. Simple frequency responses can readily be plotted from analytical models. This is done, with special attention to the influence of the serial resistance. For transient responses, a multi-cell numerical model is developed. Such model is obviously approximate, and its shortcomings, mainly of aesthetic nature, are well visible. The scope of this Note is limited to the general line propagation and reflexion behaviour ; it does not include the front-end and the itinerary thereto, nor does it discuss exterior couplings such as cross-talk. However, the developed model could be used to include these.

  17. Multiband Slot-Based Dual Composite Right/Left-Handed Transmission Line

    Directory of Open Access Journals (Sweden)

    E. Abdo-Sanchez

    2012-10-01

    Full Text Available A dual Composite Right-/Left-Handed Transmission Line (CRLH TL implementation that presents multiband behaviour is proposed in this contribution. The artificial TL is realized by loading a host microstrip line with alternate rectangular stubs and slots. The required series and shunt immittances are respectively provided by the slot and the stub. Due to the distributed nature of these immittances, the resultant phase response presents theoretically infinite RH and LH alternate bands, thus being appropriate for multiband applications. The design methodology is described with the help of a proposed TLs-based equivalent circuit and highlights the simplicity for balance condition. Full wave simulated results of the dispersion characteristics and frequency response of a unit-cell and a three-cells structure are presented.

  18. Development of an x-ray klystron modulator with a pulse-forming line and magnetic switch

    International Nuclear Information System (INIS)

    Akemoto, M.; Takeda, S.

    1992-01-01

    A new type of klystron modulator has been developed for the Japan Linear Collider. It consists of a pulse-forming line (PFL), a pulse transformer and a magnetic switch. In order to realize a compact modulator, a triplate strip transmission line using deionized water as a dielectric was adapted. An Fe amorphous core was used for the magnetic switch and the pulse transformer to reduce the size and cost. A preliminary test has shown that an output pulse with a peak voltage of 550 kV, a pulse length (flat-top) of 440 ns and a rise time of 165 ns can be generated for a dummy load with an impedance of 412Ω. It was also experimentally confirmed that the power efficiency of the modulator is approximately 83%. (Author) 7 figs., 3 tabs., 2 refs

  19. Supplement Analysis for the Transmission System Vegetation Management Program FEIS (DOE/EIS-0285/SA-119 Snohomish-Murray No. 1 Transmission Line

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Mark A. [Bonneville Power Administration (BPA), Portland, OR (United States)

    2003-01-29

    Vegetation Management along the Snohomish-Murray No. 1 Transmission Line from structure 2/6 through structure 18/6. Right of way width is 95 feet. BPA proposes to remove unwanted vegetation along the right-of-way, access roads and around tower structures along the subject transmission line corridor. Total right-of-way acreage is approximately 182.8 acres. Approximately 17 miles of access roads will be cleared. Approximately 136 tower sites will be treated. See Section 1 of the attached checklist for a complete description of the proposal.

  20. Some aspects on alternative lines of magnetic confinement

    International Nuclear Information System (INIS)

    Lehnert, B.

    1991-02-01

    Facing the year 2000, some proposals for a balanced strategy of fusion research are given in this paper. Fusion research by the world community has made substantial progress, and it is now possible to build an experimental test reactor based on the tokamak confinement principle, in the form of a global commitment such as the ITER/NET project. Nevertheless further investigations are needed before the practical use of fusion energy becomes a reality. With regard to this, and to the time gap formed by the planning and construction period of ITER/NET, continued activities have to take place at the national laboratories, to preserve the quality of plasma physical research and the competence of fusion scientists and engineers, as well as to guarantee research on alternative lines aiming at an improved reactor concept. Some aspects are given in this context on the desired properties of an optimal fusion reactor, including a high plasma beta value, a minimized imposed toroidal magnetic field, controlled or non-existent disruptions, steady-state operation, minimized plasma-wall interaction, and the absence both of a stabilizing conducting wall and of active feedback systems. (au)

  1. Efficient generation of a magnetic field-free line.

    Science.gov (United States)

    Knopp, Tobias; Erbe, Marlitt; Biederer, Sven; Sattel, Timo F; Buzug, Thorsten M

    2010-07-01

    Signal encoding in magnetic particle imaging (MPI) is achieved by moving a field-free point (FFP) through the region of interest. One way to increase the sensitivity of the method is to scan the region of interest with a field-free line (FFL) instead of the FFP. Recently, the first feasible FFL coil setup was introduced. The purpose of this article is to improve the efficiency of the FFL coil geometry even further. In order to reduce the electrical power loss of the setup, an additional Maxwell coil pair is introduced that is tailored to generate the static part of the FFL field. Using the proposed coil assembly, the electrical power loss for the generation of a rotating FFL is considerably reduced compared to previously known coil setups. Furthermore, the quality of the generated FFL is significantly increased. The proposed coil assembly is almost as efficient as an equivalent FFP scanner. Furthermore, the assembly cannot only be used for FFL imaging but for FFP imaging as well. Hence, the findings of this article denote an important step toward the first practical implementation of the FFL coil geometry.

  2. Resilience of electricity grids against transmission line overloads under wind power injection at different nodes.

    Science.gov (United States)

    Schiel, Christoph; Lind, Pedro G; Maass, Philipp

    2017-09-14

    A steadily increasing fraction of renewable energy sources for electricity production requires a better understanding of how stochastic power generation affects the stability of electricity grids. Here, we assess the resilience of an IEEE test grid against single transmission line overloads under wind power injection based on the dc power flow equations and a quasi-static grid response to wind fluctuations. Thereby we focus on the mutual influence of wind power generation at different nodes. We find that overload probabilities vary strongly between different pairs of nodes and become highly affected by spatial correlations of wind fluctuations. An unexpected behaviour is uncovered: for a large number of node pairs, increasing wind power injection at one node can increase the power threshold at the other node with respect to line overloads in the grid. We find that this seemingly paradoxical behaviour is related to the topological distance of the overloaded line from the shortest path connecting the wind nodes. In the considered test grid, it occurs for all node pairs, where the overloaded line belongs to the shortest path.

  3. Thermal analysis of a transmission line for Traveling Wave Tube TWT

    International Nuclear Information System (INIS)

    Chbiki, Mounir; Laraqi, Najib; Jarno, Jean-François; Herrewyn, Jacques; Silva Botelho, Tony da

    2012-01-01

    A new analytical method has been developed to study the delay line of Traveling Waves Tubes (TWT). Our study is focused on the analysis of the hot lines shrinking phenomenon. In the studied case, unlike brazed configuration, the contact areas are not perfect, resulting in a diminution of the heat transfer process. In this work, we highlight the influence of the macro-constriction on the heat transfer rate in the various parts of a TWT the geometry of which is also relatively complex. We propose in this work an analytical study of the thermal behavior of a transmission line in established regime. First, we determine the individual thermal resistance of each component. Secondly, we estimate the global resistance of the device according to the geometrical parameters and the respective conductivities of the various elements of this line. In this analytical model, we proceed to parametric studies in order to determine the geometrical configurations that will provide the lowest global thermal resistance. We will emphasize the potential gain according to the used materials and the increase of contact areas.

  4. Big George to Carter Mountain 115-kV transmission line project, Park and Hot Springs Counties, Wyoming. Environmental Assessment

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    The Western Area Power Administration (Western) is proposing to rebuild, operate, and maintain a 115-kilovolt (kV) transmission line between the Big George and Carter Mountain Substations in northwest Wyoming (Park and Hot Springs Counties). This environmental assessment (EA) was prepared in compliance with the National Environmental Policy Act (NEPA) and the regulations of the Council on Environmental Quality (CEQ) and the Department of Energy (DOE). The existing Big George to Carter Mountain 69-kV transmission line was constructed in 1941 by the US Department of Interior, Bureau of Reclamation, with 1/0 copper conductor on wood-pole H-frame structures without an overhead ground wire. The line should be replaced because of the deteriorated condition of the wood-pole H-frame structures. Because the line lacks an overhead ground wire, it is subject to numerous outages caused by lightning. The line will be 54 years old in 1995, which is the target date for line replacement. The normal service life of a wood-pole line is 45 years. Under the No Action Alternative, no new transmission lines would be built in the project area. The existing 69-kV transmission line would continue to operate with routine maintenance, with no provisions made for replacement.

  5. Construction of Superconducting Magnet System for the J-PARC Neutrino Beam Line

    Energy Technology Data Exchange (ETDEWEB)

    Nakamoto, T.; Wanderer, P.; Sasaki, K.; Ajima, Y.; Araoka, O.; Fujii, Y.; Hastings, N.; Higashi, N.; Iida, M.; Ishii, T.; Kimura, N.; Kobayashi, T.; Makida, Y.; Nakadaira, T.; Ogitsu, T.; Ohhata, H.; Okamura, T.; Sakashita, K.; Sugawara, S.; Suzuki, S.; Tanaka, K.; Tomaru, T.; Terashima, A.; Yamamoto, A.; Ichikawa, A.; Kakuno, H.; Anerella, M.; Escallier, J.; Ganetis, G.; gupta, R.; Jain, A.; Muratore, J.; Parker, B.; Boussuge, T.; Charrier, J.-P.; Arakawa, M.; Ichihara, T.; Minato, T.; Okada, Y.; Itou, A.; Kumaki, T.; Nagami, M.; Takahashi, T.

    2009-10-18

    Following success of a prototype R&D, construction of a superconducting magnet system for J-PARC neutrino beam line has been carried out since 2005. A new conceptual beam line with the superconducting combined function magnets demonstrated the successful beam transport to the neutrino production target.

  6. The Magnetic Physical Optics Scattered Field in Terms of a Line Integral

    DEFF Research Database (Denmark)

    Meincke, Peter; Breinbjerg, Olav; Jørgensen, Erik

    2000-01-01

    An exact line integral representation Is derived for the magnetic physical optics field scattered by a perfectly electrically conducting planar plate illuminated by a magnetic Hertzian dipole. A numerical example is presented to illustrate the exactness of the line integral representation...

  7. An Exact Line Integral Representation of the Magnetic Physical Optics Scattered Field

    DEFF Research Database (Denmark)

    Meincke, Peter; Breinbjerg, Olav; Jørgensen, Erik

    2003-01-01

    An exact line integral representation is derived for the magnetic physical optics field scattered by a perfectly electrically conducting planar plate illuminated by electric or magnetic Hertzian dipoles. The positions of source and observation points can be almost arbitrary. Numerical examples...... are presented to illustrate the exactness of the line integral representation....

  8. Laser-line rejection or transmission filters based on surface structures built on infrared transmitting materials

    Science.gov (United States)

    Hobbs, Douglas S.

    2005-05-01

    Night vision and related thermal imaging systems play a critical role in the protection of our nation's security. These systems record images using video cameras designed for operation in the infrared (IR) region of the light spectrum. As with any imaging system, increased functionality and new information is gained when discrete portions of the observed light spectrum are analyzed separately using optical filters. Highly discriminating filters are needed to increase the sensitivity of atmospheric chemical sensors, to enable multi-spectral imaging and secure laser communications links, and to protect imaging systems from damage due to attack by high power laser weapons. Today, the performance of IR light filters is inadequate for many applications. Filters capable of efficient rejection of multiple discrete wavelength bands, combined with high transmission for wavelengths outside the rejection bands, do not exist. A new type of narrow-band optical filter capable of protecting critical imaging systems from attack from laser weapons operating at multiple wavelengths, is being developed. Based on rugged surface-structure wave-guide resonant holograms, the new filters will be capable of rejecting better than 99% of IR light within each notch, while maintaining the same level of transmission outside each notch covering a broad range of the IR spectrum. The theory, design and fabrication of surface structure, laser-line rejection and transmission filters built upon infrared transmitting materials, will be described. Optical performance data for prototype structures will be presented.

  9. Secure and Time-Aware Communication of Wireless Sensors Monitoring Overhead Transmission Lines.

    Science.gov (United States)

    Mazur, Katarzyna; Wydra, Michal; Ksiezopolski, Bogdan

    2017-07-11

    Existing transmission power grids suffer from high maintenance costs and scalability issues along with a lack of effective and secure system monitoring. To address these problems, we propose to use Wireless Sensor Networks (WSNs) as a technology to achieve energy efficient, reliable, and low-cost remote monitoring of transmission grids. With WSNs, smart grid enables both utilities and customers to monitor, predict and manage energy usage effectively and react to possible power grid disturbances in a timely manner. However, the increased application of WSNs also introduces new security challenges, especially related to privacy, connectivity, and security management, repeatedly causing unpredicted expenditures. Monitoring the status of the power system, a large amount of sensors generates massive amount of sensitive data. In order to build an effective Wireless Sensor Network (WSN) for a smart grid, we focus on designing a methodology of efficient and secure delivery of the data measured on transmission lines. We perform a set of simulations, in which we examine different routing algorithms, security mechanisms and WSN deployments in order to select the parameters that will not affect the delivery time but fulfill their role and ensure security at the same time. Furthermore, we analyze the optimal placement of direct wireless links, aiming at minimizing time delays, balancing network performance and decreasing deployment costs.

  10. A transmission line model for propagation in elliptical core optical fibers

    Energy Technology Data Exchange (ETDEWEB)

    Georgantzos, E.; Boucouvalas, A. C. [Department of Telecommunications and Informatics, University of Peloponnese, Karaiskaki 70, 221 00, Tripoli Greece (Greece); Papageorgiou, C. [Department of Electrical Engineering, National technical University of Athens, Iroon Politechniou 9, Kaisariani, 16121, Athens (Greece)

    2015-12-31

    The calculation of mode propagation constants of elliptical core fibers has been the purpose of extended research leading to many notable methods, with the classic step index solution based on Mathieu functions. This paper seeks to derive a new innovative method for the determination of mode propagation constants in single mode fibers with elliptic core by modeling the elliptical fiber as a series of connected coupled transmission line elements. We develop a matrix formulation of the transmission line and the resonance of the circuits is used to calculate the mode propagation constants. The technique, used with success in the case of cylindrical fibers, is now being extended for the case of fibers with elliptical cross section. The advantage of this approach is that it is very well suited to be able to calculate the mode dispersion of arbitrary refractive index profile elliptical waveguides. The analysis begins with the deployment Maxwell’s equations adjusted for elliptical coordinates. Further algebraic analysis leads to a set of equations where we are faced with the appearance of harmonics. Taking into consideration predefined fixed number of harmonics simplifies the problem and enables the use of the resonant circuits approach. According to each case, programs have been created in Matlab, providing with a series of results (mode propagation constants) that are further compared with corresponding results from the ready known Mathieu functions method.

  11. Transmission-Line Readout with Good Time and Space Resolutions for Planacon MCP-PMTs

    CERN Document Server

    Tang, F; Byrum, K; Drake, G; Ertley, C; Frisch, H; Genat, J-F; May, E

    2008-01-01

    With commercially-available multi-anode microchannel plate photomultiplier tubes (MCP-PMT) and electronics, resolutions significantly better than 10 psec have been achieved in small systems with a few readout channels[1,2]. For large-scale time-of-flight systems used in particle physics, which may cover tens of square meters, a solution must be found with a manageable number of electronics channels and low total power consumption on the readout electronics without degrading the system timing resolution. We present here the design of a transmission-line readout for a Photonis Planacon MCP-PMT that has these characteristics. The tube, which is 5 cm square, is characterized by signal pulse rise times in the order of 200 psec and transit time spreads (TTS) in the order of 25 psec[1, 2]. The model 85011-011 MCP has 1024 anode pads laid out in an array of 32 by 32 on the back of the tube. The proposed readout is implemented on a Rogers 4350B printed circuit board with 32 parallel 50-ohm transmission lines on 1.6 mm...

  12. Active Power Flow Optimization of Industrial Power Supply with Regard to the Transmission Line Conductor Heating

    Directory of Open Access Journals (Sweden)

    Leyzgold D.Yu.

    2015-04-01

    Full Text Available This article studies the problem of the transmission line conductor heating effect on the active power flows optimization in the local segment of industrial power supply. The purpose is to determine the optimal generation rating of the distributed power sources, in which the power flow values will correspond to the minimum active power losses in the power supply. The timeliness is the need to define the most appropriate rated power values of distributed sources which will be connected to current industrial power supply. Basing on the model of active power flow optimization, authors formulate the description of the nonlinear transportation problem considering the active power losses depending on the transmission line conductor heating. Authors proposed a new approach to the heating model parameters definition based on allowable current loads and nominal parameters of conductors as part of the optimization problem. Analysis of study results showed that, despite the relatively small active power losses reduction to the tune 0,45% due to accounting of the conductors heating effect for the present configuration of power supply, there are significant fluctuations in the required generation rating in nodes of the network to 9,32% within seasonal changes in the outer air temperature. This fact should be taken into account when selecting the optimum power of distributed generation systems, as exemplified by an arbitrary network configuration.

  13. A transmission line model for propagation in elliptical core optical fibers

    Science.gov (United States)

    Georgantzos, E.; Papageorgiou, C.; Boucouvalas, A. C.

    2015-12-01

    The calculation of mode propagation constants of elliptical core fibers has been the purpose of extended research leading to many notable methods, with the classic step index solution based on Mathieu functions. This paper seeks to derive a new innovative method for the determination of mode propagation constants in single mode fibers with elliptic core by modeling the elliptical fiber as a series of connected coupled transmission line elements. We develop a matrix formulation of the transmission line and the resonance of the circuits is used to calculate the mode propagation constants. The technique, used with success in the case of cylindrical fibers, is now being extended for the case of fibers with elliptical cross section. The advantage of this approach is that it is very well suited to be able to calculate the mode dispersion of arbitrary refractive index profile elliptical waveguides. The analysis begins with the deployment Maxwell's equations adjusted for elliptical coordinates. Further algebraic analysis leads to a set of equations where we are faced with the appearance of harmonics. Taking into consideration predefined fixed number of harmonics simplifies the problem and enables the use of the resonant circuits approach. According to each case, programs have been created in Matlab, providing with a series of results (mode propagation constants) that are further compared with corresponding results from the ready known Mathieu functions method.

  14. A transmission line model for propagation in elliptical core optical fibers

    International Nuclear Information System (INIS)

    Georgantzos, E.; Boucouvalas, A. C.; Papageorgiou, C.

    2015-01-01

    The calculation of mode propagation constants of elliptical core fibers has been the purpose of extended research leading to many notable methods, with the classic step index solution based on Mathieu functions. This paper seeks to derive a new innovative method for the determination of mode propagation constants in single mode fibers with elliptic core by modeling the elliptical fiber as a series of connected coupled transmission line elements. We develop a matrix formulation of the transmission line and the resonance of the circuits is used to calculate the mode propagation constants. The technique, used with success in the case of cylindrical fibers, is now being extended for the case of fibers with elliptical cross section. The advantage of this approach is that it is very well suited to be able to calculate the mode dispersion of arbitrary refractive index profile elliptical waveguides. The analysis begins with the deployment Maxwell’s equations adjusted for elliptical coordinates. Further algebraic analysis leads to a set of equations where we are faced with the appearance of harmonics. Taking into consideration predefined fixed number of harmonics simplifies the problem and enables the use of the resonant circuits approach. According to each case, programs have been created in Matlab, providing with a series of results (mode propagation constants) that are further compared with corresponding results from the ready known Mathieu functions method

  15. Multifilamentary bismuth (2223) multilayer-wound conductors for power transmission lines

    International Nuclear Information System (INIS)

    Mukai, H.; Shibuta, N.; Sato, K.; Hara, T.; Ishii, A.; Yamamoto, T.

    1992-01-01

    In this paper the fundamental problems of applying high-Tc superconductors to power transmission lines are studied, and prototypes of multilayer-wound conductors were fabricated and evaluated. Multifilamentary silver sheathed wires have good anti-strain properties. A 61-filament bismuth (2223) wore proved to maintain 90% of initial transport current property after 150 cycles of bending (bent-straightened-bent reversely-straightened) with 0.18% strain. A 61-filament wire of 114m unit-length was produced and proved to have a Jc of 9,700 A/cm 2 with an Ic of 9.34A for the whole length at 77.3K. Using these multifilamentary wires, prototypes of multilayer-wound conductors were produced by the react-and-wind technique. A 1.4m long three layer-wound conductor could carry 590A (Jc=7, 020A/cm 2 ) in liquid nitrogen. These results indicate that the basic problems of high-Tc superconductor application to power transmission lines will be overcome

  16. Support vector machine based fault classification and location of a long transmission line

    Directory of Open Access Journals (Sweden)

    Papia Ray

    2016-09-01

    Full Text Available This paper investigates support vector machine based fault type and distance estimation scheme in a long transmission line. The planned technique uses post fault single cycle current waveform and pre-processing of the samples is done by wavelet packet transform. Energy and entropy are obtained from the decomposed coefficients and feature matrix is prepared. Then the redundant features from the matrix are taken out by the forward feature selection method and normalized. Test and train data are developed by taking into consideration variables of a simulation situation like fault type, resistance path, inception angle, and distance. In this paper 10 different types of short circuit fault are analyzed. The test data are examined by support vector machine whose parameters are optimized by particle swarm optimization method. The anticipated method is checked on a 400 kV, 300 km long transmission line with voltage source at both the ends. Two cases were examined with the proposed method. The first one is fault very near to both the source end (front and rear and the second one is support vector machine with and without optimized parameter. Simulation result indicates that the anticipated method for fault classification gives high accuracy (99.21% and least fault distance estimation error (0.29%.

  17. Magnetic separation technique for groundwater by five HTS melt-processed bulk magnets arranged in a line

    International Nuclear Information System (INIS)

    Oka, T.; Seki, H.; Kimura, T.; Mimura, D.; Fukui, S.; Ogawa, J.; Sato, T.; Ooizumi, M.; Fujishiro, H.; Hayashi, H.; Yokoyama, K.; Stiehler, C.

    2011-01-01

    A magnetic separation was practically conducted by 10-pole HTS bulk magnets. The HTS bulk magnets were activated to 2.5 T by feeding pulsed fields of 6 T. The separation ratio of actual groundwater exceeded 70% at less than 4.8 l/min. The flocks without magnetite powder were obviously attracted to the magnetic poles. A magnetic separation study for groundwater purification has been practically conducted by using the multi-pole magnet system. The magnetic pole was composed of 10 open magnetic spaces by arranging five HTS melt-processed bulk magnets in a line in a vacuum sheath. The individual bulk magnets were activated by feeding intense pulsed magnetic fields up to 6 T. The magnetic field distribution was estimated with respect to various pole arrangements. The actual groundwater samples of Sanjo City were processed so as to form large precipitates by adding the coagulant and pH controlling. The maximum separation ratio of the iron-bearing precipitates has exceeded over 70% when slurry water was exposed to 10 magnetic poles of up to 2.5 T at a flowing rate of less than 4.8 l/min. An obvious attraction of flocks to the magnetic poles was observed even when the water contains no magnetite powder at the flow rate of 1.01 l/min. This implies the validity of the multi-pole magnet system with respect to the actual application to water purification.

  18. A New Analysis of Stark and Zeeman Effects on Hydrogen Lines in Magnetized DA White Dwarfs

    Directory of Open Access Journals (Sweden)

    Ny Kieu

    2017-11-01

    Full Text Available White dwarfs with magnetic field strengths larger than 10 T are understood to represent more than 10% of the total population of white dwarfs. The presence of such strong magnetic fields is clearly indicated by the Zeeman triplet structure visible on absorption lines. In this work, we discuss the line broadening mechanisms and focus on the sensitivity of hydrogen lines on the magnetic field. We perform new calculations in conditions relevant to magnetized DA stellar atmospheres using models inspired from magnetic fusion plasma spectroscopy. A white dwarf spectrum from the Sloan Digital Sky Survey (SDSS database is analyzed. An effective temperature is provided by an adjustment of the background radiation with a Planck function, and the magnetic field is inferred from absorption lines presenting a Zeeman triplet structure. An order-of-magnitude estimate for the electron density is also performed from Stark broadening analysis.

  19. Extremely Low Frequency Electromagnetic Field (ELF-EMF and childhood leukemia near transmission lines: a review

    Directory of Open Access Journals (Sweden)

    P. A. Kokate

    2016-04-01

    Full Text Available This article presents a systematic review of most cited studies from developed countries those shed light on the potential relation between childhood leukemia and extremely low frequency electromagnetic field (ELF-EMF. All the findings of articles critically segregated as per some neglected parameters like number of samples, exposure duration, frequency range, distance from the radiation sources, and location during measurement of magnetic field density near power lines. Literature of major 50 studies are divided according to pooled analysis / meta-analysis, residential zone assessment and case-control studies.

  20. Study of the interplay between magnetic shear and resonances using Hamiltonian models for the magnetic field lines

    International Nuclear Information System (INIS)

    Firpo, M.-C.; Constantinescu, D.

    2011-01-01

    The issue of magnetic confinement in magnetic fusion devices is addressed within a purely magnetic approach. Using some Hamiltonian models for the magnetic field lines, the dual impact of low magnetic shear is shown in a unified way. Away from resonances, it induces a drastic enhancement of magnetic confinement that favors robust internal transport barriers (ITBs) and stochastic transport reduction. When low shear occurs for values of the winding of the magnetic field lines close to low-order rationals, the amplitude thresholds of the resonant modes that break internal transport barriers by allowing a radial stochastic transport of the magnetic field lines may be quite low. The approach can be applied to assess the robustness versus magnetic perturbations of general (almost) integrable magnetic steady states, including nonaxisymmetric ones such as the important single-helicity steady states. This analysis puts a constraint on the tolerable mode amplitudes compatible with ITBs and may be proposed as a possible explanation of diverse experimental and numerical signatures of their collapses.

  1. An Improved Seeding Algorithm of Magnetic Flux Lines Based on Data in 3D Space

    Directory of Open Access Journals (Sweden)

    Jia Zhong

    2015-05-01

    Full Text Available This paper will propose an approach to increase the accuracy and efficiency of seeding algorithms of magnetic flux lines in magnetic field visualization. To obtain accurate and reliable visualization results, the density of the magnetic flux lines should map the magnetic induction intensity, and seed points should determine the density of the magnetic flux lines. However, the traditional seeding algorithm, which is a statistical algorithm based on data, will produce errors when computing magnetic flux through subdivision of the plane. To achieve higher accuracy, more subdivisions should be made, which will reduce efficiency. This paper analyzes the errors made when the traditional seeding algorithm is used and gives an improved algorithm. It then validates the accuracy and efficiency of the improved algorithm by comparing the results of the two algorithms with results from the equivalent magnetic flux algorithm.

  2. Integrating the QCM detection with magnetic separation for on-line analysis.

    Science.gov (United States)

    Tsai, Hweiyan; Lin, Yi; Chang, Hung W; Fuh, C Bor

    2008-11-15

    We investigate the feasibility of coupling the quartz crystal microbalance (QCM) with magnetic separation for on-line analysis. A flow cell was integrated with QCM and magnetic force for the analysis of magnetic and nonmagnetic samples. The resonant frequency change ((Delta)f) of QCM was related to the amount of deposited magnetic nanoparticles. This experiment demonstrates that QCM can be used as an on-line detector for magnetic separation. The QCM also gives a characteristic response of the binding between the streptavidin and biotin labeled on the magnetic nanoparticles. Biotin-labeled magnetic nanoparticles were flowed through a gold electrode of QCM to deposit as a matrix for selective capturing streptavidin. The resonant frequency change of QCM was proportional to the amounts of streptavidin captured by biotin. This technique can provide a simple, economic, and automatic method for on-line detection of biomarkers.

  3. Study and Experiment on Non-Contact Voltage Sensor Suitable for Three-Phase Transmission Line.

    Science.gov (United States)

    Zhou, Qiang; He, Wei; Xiao, Dongping; Li, Songnong; Zhou, Kongjun

    2015-12-30

    A voltage transformer, as voltage signal detection equipment, plays an important role in a power system. Presently, more and more electric power systems are adopting potential transformer and capacitance voltage transformers. Transformers are often large in volume and heavyweight, their insulation design is difficult, and an iron core or multi-grade capacitance voltage division structure is generally adopted. As a result, the detection accuracy of transformer is reduced, a huge phase difference exists between detection signal and voltage signal to be measured, and the detection signal cannot accurately and timely reflect the change of conductor voltage signal to be measured. By aiming at the current problems of electric transformation, based on electrostatic induction principle, this paper designed a non-contact voltage sensor and gained detection signal of the sensor through electrostatic coupling for the electric field generated by electric charges of the conductor to be measured. The insulation structure design of the sensor is simple and its volume is small; phase difference of sensor measurement is effectively reduced through optimization design of the electrode; and voltage division ratio and measurement accuracy are increased. The voltage sensor was tested on the experimental platform of simulating three-phase transmission line. According to the result, the designed non-contact voltage sensor can realize accurate and real-time measurement for the conductor voltage. It can be applied to online monitoring for the voltage of three-phase transmission line or three-phase distribution network line, which is in accordance with the development direction of the smart grid.

  4. Study and Experiment on Non-Contact Voltage Sensor Suitable for Three-Phase Transmission Line

    Directory of Open Access Journals (Sweden)

    Qiang Zhou

    2015-12-01

    Full Text Available A voltage transformer, as voltage signal detection equipment, plays an important role in a power system. Presently, more and more electric power systems are adopting potential transformer and capacitance voltage transformers. Transformers are often large in volume and heavyweight, their insulation design is difficult, and an iron core or multi-grade capacitance voltage division structure is generally adopted. As a result, the detection accuracy of transformer is reduced, a huge phase difference exists between detection signal and voltage signal to be measured, and the detection signal cannot accurately and timely reflect the change of conductor voltage signal to be measured. By aiming at the current problems of electric transformation, based on electrostatic induction principle, this paper designed a non-contact voltage sensor and gained detection signal of the sensor through electrostatic coupling for the electric field generated by electric charges of the conductor to be measured. The insulation structure design of the sensor is simple and its volume is small; phase difference of sensor measurement is effectively reduced through optimization design of the electrode; and voltage division ratio and measurement accuracy are increased. The voltage sensor was tested on the experimental platform of simulating three-phase transmission line. According to the result, the designed non-contact voltage sensor can realize accurate and real-time measurement for the conductor voltage. It can be applied to online monitoring for the voltage of three-phase transmission line or three-phase distribution network line, which is in accordance with the development direction of the smart grid.

  5. An improved DPSO with mutation based on similarity algorithm for optimization of transmission lines loading

    International Nuclear Information System (INIS)

    Shayeghi, H.; Mahdavi, M.; Bagheri, A.

    2010-01-01

    Static transmission network expansion planning (STNEP) problem acquires a principal role in power system planning and should be evaluated carefully. Up till now, various methods have been presented to solve the STNEP problem. But only in one of them, lines adequacy rate has been considered at the end of planning horizon and the problem has been optimized by discrete particle swarm optimization (DPSO). DPSO is a new population-based intelligence algorithm and exhibits good performance on solution of the large-scale, discrete and non-linear optimization problems like STNEP. However, during the running of the algorithm, the particles become more and more similar, and cluster into the best particle in the swarm, which make the swarm premature convergence around the local solution. In order to overcome these drawbacks and considering lines adequacy rate, in this paper, expansion planning has been implemented by merging lines loading parameter in the STNEP and inserting investment cost into the fitness function constraints using an improved DPSO algorithm. The proposed improved DPSO is a new conception, collectivity, which is based on similarity between the particle and the current global best particle in the swarm that can prevent the premature convergence of DPSO around the local solution. The proposed method has been tested on the Garver's network and a real transmission network in Iran, and compared with the DPSO based method for solution of the TNEP problem. The results show that the proposed improved DPSO based method by preventing the premature convergence is caused that with almost the same expansion costs, the network adequacy is increased considerably. Also, regarding the convergence curves of both methods, it can be seen that precision of the proposed algorithm for the solution of the STNEP problem is more than DPSO approach.

  6. METHODICAL APPROACHES TO THE CHOICE OF THE NEW GENERATION OF HIGH-VOLTAGE POWER TRANSMISSION LINE 220 kV OPTIONS

    Directory of Open Access Journals (Sweden)

    POSTOLATI V.M.

    2010-08-01

    Full Text Available The Transmission Power Lines of new generation are described in the article (single- compact, double-circuit compact, double-circuit Controlled Self-compensating High Voltage Transmission Power Lines (CSHVL. Basic principles of creation, design elements and comparative characteristics of the transmission lines of the new generation are described, the advantages of its are showed. Methodical approaches to the choosing of a new generation of transmission lines and facilities management FACTS are formulated. Methodical approaches to the choice of options for transmission lines 220 kV and facilities management are shown.

  7. Aerodynamic instability of cables in transmission power lines; Inestabilidad aerodinamica en cables de lineas de transmision

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Lopez, Alberto; Vilar Rojas, Jorge Ivan; Munoz Black, Celso J. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1995-12-31

    One of the aerodynamic instabilities of transmission power lines cables is galloping, which consists in the appearance of important cable vibrations, mainly when the wind hits orthogonally the power line. In some cases the maximum amplitude that occurs reaches several meters, even when the wind velocities in a region are well below the value used for the mechanical design of the power lines. In general terms, galloping is associated with particular climatic conditions such as low temperatures and high humidities. In these conditions a coating of ice that adheres to the cable is formed, changing its transverse cross section, propitiating the galloping, although some authors have reported galloping without ice. These climatic conditions are presented mainly in the Northern part of our country and in the high regions of the mountain zones; nevertheless, the galloping phenomenon has been reported in few cases by Comision Federal de Electricidad (CFE). The possible expansion of the power lines in these regions of the country leads to prevent the measures needed to diminish the appearance of this phenomenon. In this paper mention is made in particular of the solution adopted to the galloping problem that has appeared in the transmission power line of Salamayuca to Reforma, Ciudad Juarez, Chihuahua (CFE,1991). [Espanol] Una de las inestabilidades aerodinamicas que se presentan en los cables de lineas de transmision es el galopeo, el cual consiste en la aparicion de vibraciones importantes de los cables, sobre todo cuando el flujo del viento incide ortogonalmente a la linea. En algunos casos las amplitudes maximas que se presentan llegan a ser de varios metros, aun cuando las velocidades del viento en una region esten muy por debajo del valor empleado para el diseno mecanico de las lineas. Generalmente, el galopeo se asocia con condiciones climaticas particulares como son las bajas temperaturas y altas humedades. En estas condiciones se forma una cubierta de hielo que se

  8. Study of HV Dielectrics for High Frequency Operation in Linear and Nonlinear Transmission Lines (NLTLs) and Simulation and Development of Hybrid Nonlinear Lines for RF Generation

    Science.gov (United States)

    2016-01-27

    used to limit the IGBT current . The high voltage diodes D5 to D10 are used to protect the HV switch against negative back swing voltage, while D4 diode ...capacitance diode ,” Philips semiconductor, pp. 1-4, May 1996. 21) F. S. Yamasaki, J. O. Rossi, J. J. Barroso, “RF generation using nonlinear transmission ...AFRL-AFOSR-CL-TR-2016-0005 STUDY OF HV DIELECTRICS FOR HIGH FREQUENCY OPERATION IN LINEAR & NONLINEAR TRANSMISSION LINES (NLTLs) & SIMULATION

  9. Single-phased Fault Location on Transmission Lines Using Unsynchronized Voltages

    Directory of Open Access Journals (Sweden)

    ISTRATE, M.

    2009-10-01

    Full Text Available The increased accuracy into the fault's detection and location makes it easier for maintenance, this being the reason to develop new possibilities for a precise estimation of the fault location. In the field literature, many methods for fault location using voltages and currents measurements at one or both terminals of power grids' lines are presented. The double-end synchronized data algorithms are very precise, but the current transformers can limit the accuracy of these estimations. The paper presents an algorithm to estimate the location of the single-phased faults which uses only voltage measurements at both terminals of the transmission lines by eliminating the error due to current transformers and without introducing the restriction of perfect data synchronization. In such conditions, the algorithm can be used with the actual equipment of the most power grids, the installation of phasor measurement units with GPS system synchronized timer not being compulsory. Only the positive sequence of line parameters and sources are used, thus, eliminating the incertitude in zero sequence parameter estimation. The algorithm is tested using the results of EMTP-ATP simulations, after the validation of the ATP models on the basis of registered results in a real power grid.

  10. Multipactor threshold calculation of coaxial transmission lines in microwave applications with nonstationary statistical theory

    International Nuclear Information System (INIS)

    Lin, S.; Li, Y.; Liu, C.; Wang, H.; Zhang, N.; Cui, W.; Neuber, A.

    2015-01-01

    This paper presents a statistical theory for the initial onset of multipactor breakdown in coaxial transmission lines, taking both the nonuniform electric field and random electron emission velocity into account. A general numerical method is first developed to construct the joint probability density function based on the approximate equation of the electron trajectory. The nonstationary dynamics of the multipactor process on both surfaces of coaxial lines are modelled based on the probability of various impacts and their corresponding secondary emission. The resonant assumption of the classical theory on the independent double-sided and single-sided impacts is replaced by the consideration of their interaction. As a result, the time evolutions of the electron population for exponential growth and absorption on both inner and outer conductor, in response to the applied voltage above and below the multipactor breakdown level, are obtained to investigate the exact mechanism of multipactor discharge in coaxial lines. Furthermore, the multipactor threshold predictions of the presented model are compared with experimental results using measured secondary emission yield of the tested samples which shows reasonable agreement. Finally, the detailed impact scenario reveals that single-surface multipactor is more likely to occur with a higher outer to inner conductor radius ratio

  11. The commercial development of water repellent coatings for high voltage transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, S. R. [ORNL; Daniel, A. [Southwire Company

    2013-10-31

    The purpose of the Cooperative Research and Development Agreement (CRADA) between UT-Battelle, LLC and Southwire Company was to jointly develop a low cost, commercially viable, water-repellant anti-icing coating system for high voltage transmission lines. Icing of power lines and other structures caused by freezing rain events occurs annually in the United States, and leads to severe and prolonged power outages. These outages cause untold economic and personal distress for many American families and businesses. Researchers at the Department of Energy?s Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee have previously developed a set of superhydrophobic coatings with remarkable anti-icing properties that could potentially be sprayed or painted onto high-tension power lines and pylons. These coatings drastically reduce ice accumulation on these structures during freezing rain events. The project involved obtaining technical input, supplies and test high voltage cables from Southwire, along with the joint development of anti-icing coating techniques, which would result in a commercial license agreement between Southwire and ORNL, and potentially other companies requiring water repellent anti-icing coatings.

  12. The commercial development of water repellent coatings for high voltage transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, Scott Robert [ORNL

    2013-10-01

    The purpose of the Cooperative Research and Development Agreement (CRADA) between UT-Battelle, LLC and Southwire Company was to jointly develop a low cost, commercially viable, water-repellant anti-icing coating system for high voltage transmission lines. Icing of power lines and other structures caused by freezing rain events occurs annually in the United States, and leads to severe and prolonged power outages. These outages cause untold economic and personal distress for many American families and businesses. Researchers at the Department of Energy s Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee have previously developed a set of superhydrophobic coatings with remarkable anti-icing properties that could potentially be sprayed or painted onto high-tension power lines and pylons. These coatings drastically reduce ice accumulation on these structures during freezing rain events. The project involved obtaining technical input, supplies and test high voltage cables from Southwire, along with the joint development of anti-icing coating techniques, which would result in a commercial license agreement between Southwire and ORNL, and potentially other companies requiring water repellent anti-icing coatings.

  13. Pulsed magnet systems for high energy physics beam lines

    International Nuclear Information System (INIS)

    Praeg, W.F.

    1975-01-01

    During the past years pulsed magnet systems have been developed at Argonne National Laboratory to transport beam bursts of charged high energy particles of the Zero Gradient Synchrotron (ZGS) facility. The particular features of the switching circuits, the power supplies and the magnets are described. Included are septum, quadrupole, beam shutter and bending magnets with energies ranging from 25 J to 100 kJ. The degree to which magnet current must be repeated and held constant (flattopped) during beam spill varies from +-5 percent for a beam shutter magnet to +-0.005 percent for a bending magnet; the duration of flattop ranges from a few μs to many ms. (U.S.)

  14. Chebyshev approximations for the transmission integral for one single line in Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Flores-Lamas, H.

    1994-01-01

    An analytic expansion, to arbitrary accuracy, of the transmission integral (TI) for a single Moessbauer line is presented. This serves for calculating the effective thickness (T a ) of an absorber in Moessbauer spectroscopy even for T a >10. The new analytic expansion arises from substituting in the TI expression the exponential function by a Chebyshev polynomials series. A very fast converging series for TI is obtained and used as a test function in a least squares fit to a simulated spectrum. The test yields satisfactory results. The area and height parameters calculated were found to be in good agreement with earlier results. The present analytic method assumes that the source and absorber widths are different. ((orig.))

  15. Glass fiber -reinforced plastic tapered poles for transmission and distribution lines: development and experimental study

    International Nuclear Information System (INIS)

    Ibrahim, S.; Burachysnsky, V.; Polyzois, D.

    1999-01-01

    A research project to develop lightweight poles for use in power transmission and distribution lines and involving the use of glass fiber-reinforced plastic using the filament winding process is described. Twelve full scale specimen poles were designed, fabricated and subjected to cantilever bending to test failure modes. The test parameters included fiber orientation, ratio of longitudinal-to-circumferential fiber, and the number of layers. Results showed that local buckling was the most dominant failure mode, attributable to the high radius-to-thickness ratio of the specimen poles. Overall, however, these fiber-reinforced plastic poles compared favourably to wooden poles in carrying capacity with significant weight reduction. Lateral displacement at ultimate loads did not exceed the acceptable limit of 10 per cent of the specimen free length. 7 refs., 3 tabs., 2 figs

  16. Ontario Hydro's environmental monitoring program for HV [high voltage] transmission line projects

    International Nuclear Information System (INIS)

    Braekevelt, P.N.

    1991-01-01

    Responsible monitoring and control of environmental impacts is key to obtaining future needed approvals for new high voltage (HV) transmission line projects. Ontario Hydro's environmental monitoring program was developed as a highly structured, self-imposed monitoring system to relieve government agencies of the responsibility of developing a similar external program. The goal was to be self-policing. The historical development, program structure, standards, priority ratings, documentation, communication and computerization of the program is described. The most effective way to minimize environmental impacts is to avoid sensitive features at the route selection stage, well before any construction takes place. The environmental monitoring program is based on the following blueprint: each crew member is responsible for environmental protection; environmental problems are to be resolved at the lowest level possible; potential concerns should be resolved before they become problems; known problems should be dealt with quickly to minimize impacts; team members should work cooperatively; and formal and regular communication is emphasized

  17. Broadband Dipole-Loop Combined Nanoantenna Fed by Two-Wire Optical Transmission Line

    Directory of Open Access Journals (Sweden)

    Janilson L. de Souza

    2017-01-01

    Full Text Available This paper presents a broadband nanoantenna fed by a two-wire optical transmission line (OTL. The antenna is defined by a combination of a dipole and a loop, where only the dipole element is connected to the OTL. The analysis is fulfilled by the linear method of moments with equivalent surface impedance to model the conductors. Firstly, the nanoantenna alone is investigated, where the input impedance, current distribution, reflection coefficient, fractional bandwidth, radiation efficiency, and radiation pattern are analyzed. Then, the input impedance matching of this antenna with the OTL is considered. In this case the current, near field distribution, radiation pattern, and reflection coefficient are calculated for different geometrical parameters. The results show that the loop inserted in the circuit can increase the bandwidth up to 42% and decreases the reflection coefficient in the OTL to −25 dB.

  18. Performance evaluation of a lossy transmission lines based diode detector at cryogenic temperature.

    Science.gov (United States)

    Villa, E; Aja, B; de la Fuente, L; Artal, E

    2016-01-01

    This work is focused on the design, fabrication, and performance analysis of a square-law Schottky diode detector based on lossy transmission lines working under cryogenic temperature (15 K). The design analysis of a microwave detector, based on a planar gallium-arsenide low effective Schottky barrier height diode, is reported, which is aimed for achieving large input return loss as well as flat sensitivity versus frequency. The designed circuit demonstrates good sensitivity, as well as a good return loss in a wide bandwidth at Ka-band, at both room (300 K) and cryogenic (15 K) temperatures. A good sensitivity of 1000 mV/mW and input return loss better than 12 dB have been achieved when it works as a zero-bias Schottky diode detector at room temperature, increasing the sensitivity up to a minimum of 2200 mV/mW, with the need of a DC bias current, at cryogenic temperature.

  19. Optimized transmission-line impedance transformers for petawatt-class pulsed-power accelerators

    Directory of Open Access Journals (Sweden)

    D. R. Welch

    2008-03-01

    Full Text Available We have developed 1D analytic and 2D fully electromagnetic models of radial transmission-line impedance transformers. The models have been used to quantify the power-transport efficiency and pulse sharpening of such transformers as a function of voltage pulse width and impedance profile. For the cases considered, we find that in the limit as Γ→0 (where Γ is the ratio of the pulse width to the one-way transit time of the transformer, the transport efficiency is maximized when the impedance profile is exponential. As Γ increases from zero, the optimum profile gradually deviates from an exponential. A numerical procedure is presented that determines the optimum profile for a given pulse shape and width. The procedure can be applied to optimize the design of impedance transformers used in petawatt-class pulsed-power accelerators.

  20. Modulation of Pulse Train Using Leapfrogging Pulses Developed in Unbalanced Coupled Nonlinear Transmission Lines

    Directory of Open Access Journals (Sweden)

    Koichi Narahara

    2018-01-01

    Full Text Available The leapfrogging pulses in two unbalanced electrical nonlinear transmission lines (NLTLs with capacitive couplings are investigated for efficient modulation of a pulse train. Due to the resonant interactions, the nonlinear solitary waves in the NLTLs exhibit complementary behaviors of amplitudes and phases called leapfrogging. For maximizing resonance, both solitary waves should have a common average velocity. Sharing the common velocity, the characteristic impedance can still be freely designed for two coupled solitary waves. In this study, we characterize the leapfrogging pulses developed in unbalanced NLTLs having distinct characteristic impedance. Through the soliton perturbation theory and numerical time-domain calculations, it is found that both the leapfrogging frequency and the voltage variations of pulse amplitudes increase as the difference in the characteristic impedance becomes large. These properties can improve the on/off ratio of modulated pulse train.

  1. Design and manufacture of the RF power supply and RF transmission line for SANAEM project Prometheus

    Science.gov (United States)

    Turemen, G.; Ogur, S.; Ahiska, F.; Yasatekin, B.; Cicek, E.; Ozbey, A.; Kilic, I.; Unel, G.; Alacakir, A.

    2017-08-01

    A 1-5 MeV proton beamline is being built by the Turkish Atomic Energy Authority in collaboration with a number of graduate students from different universities. The primary goal of the project, is to acquire the design ability and manufacturing capability of all the components locally. SPP will be an accelerator and beam diagnostics test facility and it will also serve the detector development community with its low beam current. This paper discusses the design and construction of the RF power supply and the RF transmission line components such as its waveguide converters and its circulator. Additionally low and high power RF test results are presented to compare the performances of the locally produced components to the commercially available ones.

  2. Effect of feeders in 3D modeling of low impedance multilayer CPW transmission line

    Science.gov (United States)

    Zaini, R. I.; Kyabaggu, P. B. K.; Sinulingga, E. P.

    2018-02-01

    Improved characteristics with low dissipation loss MMICs are highly desirable for wireless communications. However, the current industrial MMIC design is mainly based on microstrip concept which suffered from parasitic and unwanted phenomenon especially at higher frequency (>20 GHz). On the other hand, for future wireless technology, higher frequency operation is required and on-wafer microwave characterizations as well as precise modeling of 3D Multilayer CPW components are vital. This project concerns with understanding of the microwave characteristics behavior of Multilayer CPW components in MMIC applications. Feeder effect as unwanted parts in the characteristics has been investigated to determine its relation with the half wavelength resonance of the Multilayer CPW Low Impedance Transmission Line.

  3. Low-loss monolithic transmission lines for submillimeter and terahertz frequency applications

    Science.gov (United States)

    Engel, Andrew G., Jr.; Katehi, Linda P. B.

    1991-01-01

    The design and construction of low-loss monolithic transmission lines are critical to systems which require that terahertz-power be guided to the antenna front ends. Two types of novel monolithic guiding structures, designed for the 0.3-2.0 THz and 0.1-0.3 THz ranges, respectively, are proposed. The novel waveguides are constructed from dielectric materials and structures which are available in monolithic technology so that the integration of active devices is possible. Propagation in each of the waveguides is characterized over relevant frequency ranges by applying a mode-matching technique, which takes into account all forms of electromagnetic coupling as well as losses in the dielectrics. The structures are predicted to exhibit excellent power confinement and low losses.

  4. Pollutant Dispersion Modeling in Natural Streams Using the Transmission Line Matrix Method

    Directory of Open Access Journals (Sweden)

    Safia Meddah

    2015-09-01

    Full Text Available Numerical modeling has become an indispensable tool for solving various physical problems. In this context, we present a model of pollutant dispersion in natural streams for the far field case where dispersion is considered longitudinal and one-dimensional in the flow direction. The Transmission Line Matrix (TLM, which has earned a reputation as powerful and efficient numerical method, is used. The presented one-dimensional TLM model requires a minimum input data and provides a significant gain in computing time. To validate our model, the results are compared with observations and experimental data from the river Severn (UK. The results show a good agreement with experimental data. The model can be used to predict the spatiotemporal evolution of a pollutant in natural streams for effective and rapid decision-making in a case of emergency, such as accidental discharges in a stream with a dynamic similar to that of the river Severn (UK.

  5. The Peak Control Function and its Applications to Transmission Line Effects in Class D Amplifiers

    Directory of Open Access Journals (Sweden)

    VUZA, D. T.

    2014-08-01

    Full Text Available Class D amplifiers find new applications in RFID systems, because of their high efficiency. Most textbooks describe the case of a load directly connected to the amplifier. However, in most RFID systems the usage of a transmission line is mandatory and this may introduce some novel effects, in the form of an infinite series of peaks in the system frequency response functions. If not appropriately taken care of, these effects may lead to electromagnetic compatibility problems. The purpose of the paper is to develop the theory of the peak control function, which is conceived as a tool that allows the designer to keep the magnitude of the peaks, and hence their influence on the system, into well defined limits.

  6. Numerical Calculation of Transient Thermal Characteristics in Gas-Insulated Transmission Lines

    Directory of Open Access Journals (Sweden)

    Hongtao Li

    2013-11-01

    Full Text Available For further knowledge of the thermal characteristics in gas-insulated transmission lines (GILs installed above ground, a finite-element model coupling fluid field and thermal field is established, in which the corresponding assumptions and boundary conditions are given.  Transient temperature rise processes of the GIL under the conditions of variable ambient temperature, wind velocity and solar radiation are respectively investigated. Equivalent surface convective heat transfer coefficient and heat flux boundary conditions are updated in the analysis process. Unlike the traditional finite element methods (FEM, the variability of the thermal properties with temperature is considered. The calculation results are validated by the tests results reported in the literature. The conclusion provides method and theory basis for the knowledge of transient temperature rise characteristics of GILs in open environment.

  7. Precise ion optical description of strip-line pulsed magnetic lenses

    International Nuclear Information System (INIS)

    Varentsov, D.; Spiller, P.; Eickhoff, H.; Hoffmann, D.H.H.

    2002-01-01

    A specific computer code has been developed to investigate ion optical properties of a new generation of pulsed strip-line high current magnets. The code is based on a modern 'Differential Algebra' computational technique and it is able to calculate transfer matrices of pulsed strip-line magnets up to arbitrary order. The realistic three-dimensional distribution of the magnetic field in pulsed lenses as well as all the fringing field effects are taken into account in the simulations. We have demonstrated, that for precise description of such magnets one cannot use the existing ion optical codes where ideal multipole field distributions and fringing fields, typical for conventional iron-dominated magnets are assumed. The transfer matrix elements of pulsed strip-line lenses differ significantly from those of conventional magnets, especially in higher orders

  8. Adapting AC Lines to DC Grids for Large-Scale Renewable Power Transmission

    Directory of Open Access Journals (Sweden)

    D. Marene Larruskain

    2014-10-01

    Full Text Available All over the world, governments of different countries are nowadays promoting the use of clean energies in order to achieve sustainable energy systems. In this scenario, since the installed capacity is continuously increasing, renewable sources can play an important role. Notwithstanding that, some important problems may appear when connecting these sources to the grid, being the overload of distribution lines one of the most relevant. In fact, renewable generation is usually connected to the nearest AC grid, although this HV system may not have been designed considering distributed generation. In the particular case of large wind farms, the electrical grid has to transmit all the power generated by wind energy and, as a consequence, the AC system may get overloaded. It is therefore necessary to determine the impact of wind power transmission so that appropriate measures can be taken. Not only are these measures influenced by the amount of power transmitted, but also by the quality of the transmitted power, due to the output voltage fluctuation caused by the highly variable nature of wind. When designing a power grid, although AC systems are usually the most economical solution because of its highly proven technology, HVDC may arise in some cases (e.g. offshore wind farms as an interesting alternative, offering some added values such as lower losses and better controllability. This way, HVDC technology can solve most of the aforementioned problems and has a good potential for future use. Additionally, the fast development of power electronics based on new and powerful semiconductor devices allow the spread of innovative technologies, such as VSC-HVDC, which can be applied to create DC grids. This paper focuses on the main aspects involved in adapting the existing overhead AC lines to DC grids, with the objective of improving the transmission of distributed renewable energy to the centers of consumption.

  9. Characterization of devices, circuits, and high-temperature superconductor transmission lines by electro-optic testing

    Science.gov (United States)

    Whitaker, John F.

    1991-01-01

    The development of a capability for testing transmission lines, devices, and circuits using the optically-based technique of electro-optics sampling was the goal of this project. Electro-optic network analysis of a high-speed device was demonstrated. The project involved research on all of the facets necessary in order to realize this result, including the discovery of the optimum electronic pulse source, development of an adequate test fixture, improvement of the electro-optic probe tip, and identification of a device which responded at high frequency but did not oscillate in the test fixture. In addition, during the process of investigating patterned high-critical-temperature superconductors, several non-contacting techniques for the determination of the transport properties of high T(sub c) films were developed and implemented. These are a transient, optical pump-probe, time-resolved reflectivity experiment, an impulsive-stimulated Raman scattering experiment, and a terahertz-beam coherent-spectroscopy experiment. The latter technique has enabled us to measure both the complex refractive index of an MgO substrate used for high-T(sub c) films and the complex conductivity of a YBa2Cu3O(7-x) sample. This information was acquired across an extremely wide frequency range: from the microwave to the submillimeter-wave regime. The experiments on the YBCO were conducted without patterning of, or contact to, the thin film. Thus, the need for the more difficult transmission-line experiments was eliminated. Progress in all of these areas was made and is documented in a number of papers. These papers may be found in the section listing the abstracts of the publications that were issued during the course of the research.

  10. Acoustic noise background and sound transmission tests in a slurry line at the HYGAS Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    Raptis, A.C.; Sheen, S.H.; Roach, P.D.; Mech, J.F.

    1979-01-01

    A State-of-the-Art report on instrumentation needs for coal conversion demonstration plants indicated that acoustic/ultrasonic techniques may be applied to measure two-phase flows found in coal conversion processes. Later theoretical feasibilities studies on the feasibility of acoustic/ultrasonic techniques to measure mass flow in coal conversion process streams were reported. These studies were based on limited theoretical and experimental results found in the literature. In the present work actual experimental results necessary to design a flowmeter for coal/liquid streams are presented. Acoustic data obtained from tests at the low pressure slurry line of the HYGAS char conversion pilot plant are presented. The data consist of the acoustic noise background and the sound transmission loss for the cases of 0, 18, and 33% char by weight in toluene and benzene. Spectra of noise background were scanned from 10 kHz to 1 MHz. Most acoustic energy of the noise background was shown to be below 500 kHz. Isolated acoustic events were also observed; such events represent either the acoustic resonance of the pipe or the resonant response of the transducer. Relative sound transmission losses were measured by the pitch catch pulse mode operation over the frequency range of 100 kHz to 1 MHz. Strong char concentration dependence with attenuation was observed. Results are discussed in terms of the sonar equation to indicate the feasibility of an ultrasonic or acoustic device applied to char conversion processes.

  11. Continuous monitoring of a dam flush in a shallow river using two crossing ultrasonic transmission lines

    International Nuclear Information System (INIS)

    Kawanisi, Kiyosi; Razaz, Mahdi; Yano, Jyunki; Ishikawa, Kazuhiko

    2013-01-01

    Continuous measurements of streamflow and water temperature were carried out in a shallow gravel-bed river during dam flushing operations using a new shallow acoustic system with two crossing transmission lines. The fluvial acoustic system (FAS) was equipped with four 25 kHz broadband omnidirectional transducers. The reciprocal sound transmissions were performed between the two pairs of acoustic stations, located on both sides of the river. The four-station FAS enabled the measurement of the stream direction in addition to the depth- and range-averaged sound speed, and therefore water velocity. Discharge values computed from FAS reports were compared to those estimated by the moving-boat acoustic Doppler current profiler (ADCP) and rating curve (RC) methods. FAS estimates were in good agreement with ADCP and RC estimates over a range of 50 to 180 m 3 s −1 . The temperature gradients induced strong sound scattering for the 25 kHz FAS. The fine suspended sediment particles also induced a gradual decrease in the signal-to-noise ratio of the FAS. Nevertheless, the FAS has been proved to be a reliable and accurate technique for the continuous measurement of cross-sectional average velocity/water temperature. (paper)

  12. Calculation of voltages in electric power transmission lines during historic geomagnetic storms: An investigation using realistic earth impedances

    Science.gov (United States)

    Lucas, Greg M.; Love, Jeffrey J.; Kelbert, Anna

    2018-01-01

    Commonly, one-dimensional (1-D) Earth impedances have been used to calculate the voltages induced across electric power transmission lines during geomagnetic storms under the assumption that much of the three-dimensional structure of the Earth gets smoothed when integrating along power transmission lines. We calculate the voltage across power transmission lines in the mid-Atlantic region with both regional 1-D impedances and 64 empirical 3-D impedances obtained from a magnetotelluric survey. The use of 3-D impedances produces substantially more spatial variance in the calculated voltages, with the voltages being more than an order of magnitude different, both higher and lower, than the voltages calculated utilizing regional 1-D impedances. During the March 1989 geomagnetic storm 62 transmission lines exceed 100 V when utilizing empirical 3-D impedances, whereas 16 transmission lines exceed 100 V when utilizing regional 1-D impedances. This demonstrates the importance of using realistic impedances to understand and quantify the impact that a geomagnetic storm has on power grids.

  13. Time-resolved X-ray transmission microscopy on magnetic microstructures

    International Nuclear Information System (INIS)

    Puzic, Aleksandar

    2007-01-01

    Three excitation schemes were designed for stroboscopic imaging of magnetization dynamics with time-resolved magnetic transmission X-ray microscopy (TR-MTXM). These techniques were implemented into two types of X-ray microscopes, namely the imaging transmission X-ray microscope (ITXM) and the scanning transmission X-ray microscope (STXM), both installed at the electron storage ring of the Advanced Light Source in Berkeley, USA. Circular diffraction gratings (Fresnel zone plates) used in both microscopes as focusing and imaging elements presently allow for lateral resolution down to 30 nm. Magnetic imaging is performed by using the X-ray magnetic circular dichroism (XMCD) as element specific contrast mechanism. The developed methods have been successfully applied to the experimental investigation of magnetization dynamics in ferromagnetic microstructures. A temporal resolution well below 100 ps was achieved. A conventional pump-probe technique was implemented first. The dynamic response of the magnetization excited by a broadband pulsed magnetic field was imaged spatially resolved using focused X-ray flashes. As a complementary method, the spatially resolved ferromagnetic resonance (SR-FMR) technique was developed for experimental study of magnetization dynamics in the frequency domain. As a third excitation mode, the burst excitation was implemented. The performance and efficiency of the developed methods have been demonstrated by imaging the local magnetization dynamics in laterally patterned ferromagnetic thin-film elements and three-layer stacks. The existence of multiple eigenmodes in the excitation spectra of ferromagnetic microstructures has been verified by using the pump-probe technique. Magnetostatic spin waves were selectively excited and detected with a time resolution of 50 ps using the SR-FMR technique. Thorough analysis of 20 in most cases independently prepared samples has verified that vortices which exhibit a low-amplitude switching of their core

  14. Time-resolved X-ray transmission microscopy on magnetic microstructures; Zeitaufloesende Roentgentransmissionsmikroskopie an magnetischen Mikrostrukturen

    Energy Technology Data Exchange (ETDEWEB)

    Puzic, Aleksandar

    2007-10-23

    Three excitation schemes were designed for stroboscopic imaging of magnetization dynamics with time-resolved magnetic transmission X-ray microscopy (TR-MTXM). These techniques were implemented into two types of X-ray microscopes, namely the imaging transmission X-ray microscope (ITXM) and the scanning transmission X-ray microscope (STXM), both installed at the electron storage ring of the Advanced Light Source in Berkeley, USA. Circular diffraction gratings (Fresnel zone plates) used in both microscopes as focusing and imaging elements presently allow for lateral resolution down to 30 nm. Magnetic imaging is performed by using the X-ray magnetic circular dichroism (XMCD) as element specific contrast mechanism. The developed methods have been successfully applied to the experimental investigation of magnetization dynamics in ferromagnetic microstructures. A temporal resolution well below 100 ps was achieved. A conventional pump-probe technique was implemented first. The dynamic response of the magnetization excited by a broadband pulsed magnetic field was imaged spatially resolved using focused X-ray flashes. As a complementary method, the spatially resolved ferromagnetic resonance (SR-FMR) technique was developed for experimental study of magnetization dynamics in the frequency domain. As a third excitation mode, the burst excitation was implemented. The performance and efficiency of the developed methods have been demonstrated by imaging the local magnetization dynamics in laterally patterned ferromagnetic thin-film elements and three-layer stacks. The existence of multiple eigenmodes in the excitation spectra of ferromagnetic microstructures has been verified by using the pump-probe technique. Magnetostatic spin waves were selectively excited and detected with a time resolution of 50 ps using the SR-FMR technique. Thorough analysis of 20 in most cases independently prepared samples has verified that vortices which exhibit a low-amplitude switching of their core

  15. Multi-band Microwave Antennas and Devices based on Generalized Negative-Refractive-Index Transmission Lines

    Science.gov (United States)

    Ryan, Colan Graeme Matthew

    Focused on the quad-band generalized negative-refractive-index transmission line (G-NRI-TL), this thesis presents a variety of novel printed G-NRI-TL multi-band microwave device and antenna prototypes. A dual-band coupled-line coupler, an all-pass G-NRI-TL bridged-T circuit, a dual-band metamaterial leaky-wave antenna, and a multi-band G-NRI-TL resonant antenna are all new developments resulting from this research. In addition, to continue the theme of multi-band components, negative-refractive-index transmission lines are used to create a dual-band circularly polarized transparent patch antenna and a two-element wideband decoupled meander antenna system. High coupling over two independently-specified frequency bands is the hallmark of the G-NRI-TL coupler: it is 0.35lambda0 long but achieves approximately -3 dB coupling over both bands with a maximum insertion loss of 1 dB. This represents greater design flexibility than conventional coupled-line couplers and less loss than subsequent G-NRI-TL couplers. The single-ended bridged-T G-NRI-TL offers a metamaterial unit cell with an all-pass magnitude response up to 8 GHz, while still preserving the quad-band phase response of the original circuit. It is shown how the all-pass response leads to wider bandwidths and improved matching in quad-band inverters, power dividers, and hybrid couplers. The dual-band metamaterial leaky-wave antenna presented here was the first to be reported in the literature, and it allows broadside radiation at both 2 GHz and 6 GHz without experiencing the broadside stopband common to conventional periodic antennas. Likewise, the G-NRI-TL resonant antenna is the first reported instance of such a device, achieving quad-band operation between 2.5 GHz and 5.6 GHz, with a minimum radiation efficiency of 80%. Negative-refractive-index transmission line loading is applied to two devices: an NRI-TL meander antenna achieves a measured 52% impedance bandwidth, while a square patch antenna incorporates

  16. Planar quadrature RF transceiver design using common-mode differential-mode (CMDM transmission line method for 7T MR imaging.

    Directory of Open Access Journals (Sweden)

    Ye Li

    Full Text Available The use of quadrature RF magnetic fields has been demonstrated to be an efficient method to reduce transmit power and to increase the signal-to-noise (SNR in magnetic resonance (MR imaging. The goal of this project was to develop a new method using the common-mode and differential-mode (CMDM technique for compact, planar, distributed-element quadrature transmit/receive resonators for MR signal excitation and detection and to investigate its performance for MR imaging, particularly, at ultrahigh magnetic fields. A prototype resonator based on CMDM method implemented by using microstrip transmission line was designed and fabricated for 7T imaging. Both the common mode (CM and the differential mode (DM of the resonator were tuned and matched at 298MHz independently. Numerical electromagnetic simulation was performed to verify the orthogonal B1 field direction of the two modes of the CMDM resonator. Both workbench tests and MR imaging experiments were carried out to evaluate the performance. The intrinsic decoupling between the two modes of the CMDM resonator was demonstrated by the bench test, showing a better than -36 dB transmission coefficient between the two modes at resonance frequency. The MR images acquired by using each mode and the images combined in quadrature showed that the CM and DM of the proposed resonator provided similar B1 coverage and achieved SNR improvement in the entire region of interest. The simulation and experimental results demonstrate that the proposed CMDM method with distributed-element transmission line technique is a feasible and efficient technique for planar quadrature RF coil design at ultrahigh fields, providing intrinsic decoupling between two quadrature channels and high frequency capability. Due to its simple and compact geometry and easy implementation of decoupling methods, the CMDM quadrature resonator can possibly be a good candidate for design blocks in multichannel RF coil arrays.

  17. Cyclotron Lines: From Magnetic Field Strength Estimators to ...

    Indian Academy of Sciences (India)

    Chandreyee Maitra

    2017-09-12

    Sep 12, 2017 ... Due to the effect of a non-spherical emission zone and the scattering cross sections of the photons which are altered in the presence of strong magnetic fields (i.e. acquire different dependencies depending on whether they escape parallel or perpen- dicular to the magnetic field vector (Becker 1998)),.

  18. Flexible superconducting Nb transmission lines on thin film polyimide for quantum computing applications

    Science.gov (United States)

    Tuckerman, David B.; Hamilton, Michael C.; Reilly, David J.; Bai, Rujun; Hernandez, George A.; Hornibrook, John M.; Sellers, John A.; Ellis, Charles D.

    2016-08-01

    We describe progress and initial results achieved towards the goal of developing integrated multi-conductor arrays of shielded controlled-impedance flexible superconducting transmission lines with ultra-miniature cross sections and wide bandwidths (dc to >10 GHz) over meter-scale lengths. Intended primarily for use in future scaled-up quantum computing systems, such flexible thin-film niobium/polyimide ribbon cables could provide a physically compact and ultra-low thermal conductance alternative to the rapidly increasing number of discrete coaxial cables that are currently used by quantum computing experimentalists to transmit signals between the several low-temperature stages (from ˜4 K down to ˜20 mK) of a dilution refrigerator. We have concluded that these structures are technically feasible to fabricate, and so far they have exhibited acceptable thermo-mechanical reliability. S-parameter results are presented for individual 2-metal layer Nb microstrip structures having 50 Ω characteristic impedance; lengths ranging from 50 to 550 mm were successfully fabricated. Solderable pads at the end terminations allowed testing using conventional rf connectors. Weakly coupled open-circuit microstrip resonators provided a sensitive measure of the overall transmission line loss as a function of frequency, temperature, and power. Two common microelectronic-grade polyimide dielectrics, one conventional and the other photo-definable (PI-2611 and HD-4100, respectively) were compared. Our most striking result, not previously reported to our knowledge, was that the dielectric loss tangents of both polyimides, over frequencies from 1 to 20 GHz, are remarkably low at deep cryogenic temperatures, typically 100× smaller than corresponding room temperature values. This enables fairly long-distance (meter-scale) transmission of microwave signals without excessive attenuation, and also permits usefully high rf power levels to be transmitted without creating excessive dielectric

  19. Transmission Lines or Poles, Electric, Electric transmission lines locations provided to us from Kansas City Power and Light and City of Gardner only at this time. AIMS is working on getting other providers in area. Data is limited to CUE (Collaborative Utility Exchange) Participants and subc, Published in 2004, Johnson County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Transmission Lines or Poles, Electric dataset current as of 2004. Electric transmission lines locations provided to us from Kansas City Power and Light and City of...

  20. A new algorithm for optimum voltage and reactive power control for minimizing transmission lines losses

    International Nuclear Information System (INIS)

    Ghoudjehbaklou, H.; Danai, B.

    2001-01-01

    Reactive power dispatch for voltage profile modification has been of interest to power utilities. Usually local bus voltages can be altered by changing generator voltages, reactive shunts, ULTC transformers and SVCs. Determination of optimum values for control parameters, however, is not simple for modern power system networks. Heuristic and rather intelligent algorithms have to be sought. In this paper a new algorithm is proposed that is based on a variant of a genetic algorithm combined with simulated annealing updates. In this algorithm a fuzzy multi-objective a approach is used for the fitness function of the genetic algorithm. This fuzzy multi-objective function can efficiently modify the voltage profile in order to minimize transmission lines losses, thus reducing the operating costs. The reason for such a combination is to utilize the best characteristics of each method and overcome their deficiencies. The proposed algorithm is much faster than the classical genetic algorithm and cna be easily integrated into existing power utilities software. The proposed algorithm is tested on an actual system model of 1284 buses, 799 lines, 1175 fixed and ULTC transformers, 86 generators, 181 controllable shunts and 425 loads

  1. Treatment of biodiversity issues in impact assessment of electricity power transmission lines: A Finnish case review

    International Nuclear Information System (INIS)

    Soederman, Tarja

    2006-01-01

    The Environmental Impact Assessment (EIA) process concerning the route of a 400 kV power transmission line between Loviisa and Hikiae in southern Finland was reviewed in order to assess how biodiversity issues are treated and to provide suggestions on how to improve the effectiveness of treatment of biodiversity issues in impact assessment of linear development projects. The review covered the whole assessment process, including interviews of stakeholders, participation in the interest group meetings and review of all documents from the project. The baseline studies and assessment of direct impacts in the case study were detailed but the documentation, both the assessment programme and the assessment report, only gave a partial picture of the assessment process. All existing information, baseline survey and assessment methods should be addressed in the scoping phase in order to promote interaction between all stakeholders. In contrast to the assessment of the direct effects, which first emphasized impacts on the nationally important and protected flying squirrel but later expanded to deal with the assessment of impacts on ecologically important sites, the indirect and cumulative impacts of the power line were poorly addressed. The public was given the opportunity to become involved in the EIA process. However, they were more concerned with impacts on their properties and less so on biodiversity and species protection issues. This suggests that the public needs to become more informed about locally important features of biodiversity

  2. Prediction of the dynamic response of complex transmission line systems for unsteady pressure measurements

    International Nuclear Information System (INIS)

    Antonini, C; Persico, G; Rowe, A L

    2008-01-01

    Among the measurement and control systems of gas turbine engines, a recent new issue is the possibility of performing unsteady pressure measurements to detect flow anomalies in an engine or to evaluate loads on aerodynamic surfaces. A possible answer to this demand could be extending the use of well known and widely used transmission line systems, which have been applied so far to steady monitoring, to unsteady measurements thanks to proper dynamic modeling and compensation. Despite the huge number of models existing in the literature, a novel method has been developed, which is at the same time easy-to-handle, flexible and capable of reproducing the actual physics of the problem. Furthermore, the new model is able to deal with arbitrary complex networks of lines and cavities, and thus its applicability is not limited to series-connected systems. The main objectives of this paper are to show the derivation of the model, its validation against experimental tests and example of its applicability

  3. Mechanism of the tonal emission from ac high voltage overhead transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Straumann, Ueli, E-mail: stulrich@ethz.ch [High Voltage Laboratory, ETH Zurich, CH-8092 Zuerich (Switzerland)

    2011-02-23

    Foul weather conditions can lead to corona discharges on high voltage overhead transmission lines which are perceivable as an audible broadband crackling and hissing noise. In such situations this noise is often accompanied by a humming noise at twice the mains frequency (2f). While the crackling and hissing noise component was widely investigated in the past, the 2f-component went largely uncommented. Only a scant amount of literature suggests mechanisms explaining the occurrence of this emission, but these suggestions are either vague or controversial. In this paper a mechanism analogous to that of ion loudspeakers is presented, which describes the sound levels of audible 2f-emissions from high voltage model lines quantitatively in a satisfactory manner. While the broadband component of corona noise emissions has its immediate origin in the discharges themselves, the 2f-emissions arise from the drift of ions left behind by the discharges. Due to collisions with gas molecules, these ions cause in the sum a rise of heat in and a force applying on the neutral gas, thus producing the 2f-emissions. Depending on the situation, both can give rise to contributions of similar magnitude.

  4. Mechanism of the tonal emission from ac high voltage overhead transmission lines

    International Nuclear Information System (INIS)

    Straumann, Ueli

    2011-01-01

    Foul weather conditions can lead to corona discharges on high voltage overhead transmission lines which are perceivable as an audible broadband crackling and hissing noise. In such situations this noise is often accompanied by a humming noise at twice the mains frequency (2f). While the crackling and hissing noise component was widely investigated in the past, the 2f-component went largely uncommented. Only a scant amount of literature suggests mechanisms explaining the occurrence of this emission, but these suggestions are either vague or controversial. In this paper a mechanism analogous to that of ion loudspeakers is presented, which describes the sound levels of audible 2f-emissions from high voltage model lines quantitatively in a satisfactory manner. While the broadband component of corona noise emissions has its immediate origin in the discharges themselves, the 2f-emissions arise from the drift of ions left behind by the discharges. Due to collisions with gas molecules, these ions cause in the sum a rise of heat in and a force applying on the neutral gas, thus producing the 2f-emissions. Depending on the situation, both can give rise to contributions of similar magnitude.

  5. Mechanical engineering and design criteria for the Magnetically Insulated Transmission Experiment Accelerator

    International Nuclear Information System (INIS)

    Staller, G.E.; Hamilton, I.D.; Aker, M.F.; Fifer, H.G.

    1978-02-01

    A single-unit electron beam accelerator was designed, fabricated, and assembled in Sandia's Technical Area V to conduct magnetically insulated transmission experiments. Results of these experiments will be utilized in the future design of larger, more complex accelerators. This design makes optimum use of existing facilities and equipment. When designing new components, possible future applications were considered as well as compatibility with existing facilities and hardware

  6. Resonance Frequency and Bandwidth of the Negative/Positive n Mode of a Composite Right-/Left-Handed Transmission Line

    Directory of Open Access Journals (Sweden)

    Seong-Jung Kim

    2018-01-01

    Full Text Available In this study, the analytic expression for the positive/negative nth-mode resonance frequency of an N unit cell composite right-/left-handed (CRLH transmission line is derived. To explain the resonance mechanism of the nth mode, especially for the negative mode, the current distribution of the N unit cell CRLH transmission line is investigated with a circuit simulation. Results show that both positive and negative nth resonance modes have n times current variations, but their phase difference is 180° as expected. Moreover, the positive nth resonance occurs at a high frequency, whereas the negative nth resonance transpires at a low frequency, thus indicating that the negative resonance mode can be utilized for a small resonator. The correlation between the slope of the dispersion curve and the bandwidth is also observed. In sum, the balanced condition of the CRLH transmission line provides a broader bandwidth than the unbalanced condition.

  7. EVOLUTION OF THE MAGNETIC FIELD LINE DIFFUSION COEFFICIENT AND NON-GAUSSIAN STATISTICS

    Energy Technology Data Exchange (ETDEWEB)

    Snodin, A. P. [Department of Mathematics, Faculty of Applied Science, King Mongkut’s University of Technology North Bangkok, Bangkok 10800 (Thailand); Ruffolo, D. [Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand); Matthaeus, W. H. [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States)

    2016-08-20

    The magnetic field line random walk (FLRW) plays an important role in the transport of energy and particles in turbulent plasmas. For magnetic fluctuations that are transverse or almost transverse to a large-scale mean magnetic field, theories describing the FLRW usually predict asymptotic diffusion of magnetic field lines perpendicular to the mean field. Such theories often depend on the assumption that one can relate the Lagrangian and Eulerian statistics of the magnetic field via Corrsin’s hypothesis, and additionally take the distribution of magnetic field line displacements to be Gaussian. Here we take an ordinary differential equation (ODE) model with these underlying assumptions and test how well it describes the evolution of the magnetic field line diffusion coefficient in 2D+slab magnetic turbulence, by comparisons to computer simulations that do not involve such assumptions. In addition, we directly test the accuracy of the Corrsin approximation to the Lagrangian correlation. Over much of the studied parameter space we find that the ODE model is in fairly good agreement with computer simulations, in terms of both the evolution and asymptotic values of the diffusion coefficient. When there is poor agreement, we show that this can be largely attributed to the failure of Corrsin’s hypothesis rather than the assumption of Gaussian statistics of field line displacements. The degree of non-Gaussianity, which we measure in terms of the kurtosis, appears to be an indicator of how well Corrsin’s approximation works.

  8. Distance Protection Impedance Measurement for Inhomogeneous Multiple-Circuit 400/150 kV Transmission Lines with Shared Towers

    DEFF Research Database (Denmark)

    Bak, Claus Leth; Sigurbjörnsson, Ragnar; Bukh, Bjarne

    2016-01-01

    Combined transmission lines where different voltage levels shares same towers are used in transmission systems in order to save way of right. Faults between different voltage levels results in complex fault current distributions due to mutual couplings and the fact that the faulted phases no longer...... modelling followed by fault loop impedance calculation is possible. Selected results show that fault loop impedance can be located in unexpected regions of the complex R-X plane....

  9. Study of pitting corrosion in line-pipe steel under the influence of remanent magnetization

    Energy Technology Data Exchange (ETDEWEB)

    Espina-Hernandez, J.H.; Caleyo, F.; Hallen, J.M. [Instituto Politecnico Nacional (IPN), Zacatenco (Mexico)

    2009-07-01

    The influence of remanent magnetization on pitting corrosion in line-pipe steels is studied. Pitting corrosion experiments have been carried out on samples of an API 5L grade 52 steel under a magnetization level of the same order of magnitude of the remanent magnetization in the pipeline wall after in-line inspection based on magnetic flux leakage. The samples were magnetized using rings of the same grade as the investigated steel. Immediately after magnetization, the investigated samples were subjected to pitting by immersing them in a solution containing dissolved Cl{sup -} and SO{sup 2-}{sub 4} and ions. The pitting experiments were conducted during a seven days period. The pit depth distribution and the maximum pit depth in each sample were recorded and used to conduct extreme value analyses of the pitting process in magnetized and non-magnetized control samples. The statistical assessment of the pitting corrosion data collected during this study shows that the magnetic field reduces the average depth of the pit population and also the extreme pit depth values that can be predicted from the maximum values observed in the magnetized samples in comparison with to the non-magnetized control samples. Scanning electron microscopy observations show that the magnetic field alters the pit morphology by increasing the pit mouth opening. (author)

  10. Comparison of lumped-element and transmission-line models for thickness-shear-mode quartz resonator sensors

    Energy Technology Data Exchange (ETDEWEB)

    Cernosek, R.W.; Martin, S.J. [Sandia National Laboratories, Albuquerque, NM (United States); Hillman, A.R. [Univ. of Leicester (United Kingdom). Dept. of Chemistry] [and others

    1997-08-01

    Both a transmission-line model and its simpler variant, a lumped-element model, can be used to predict the responses of a thickness-shear-mode quartz resonator sensor. Relative deviations in the parameters computed by the two models (shifts in resonant frequency and motional resistance) do not exceed 3% for most practical sensor configurations operating at the fundamental resonance. If the ratio of the load surface mechanical impedance to the quartz shear characteristic impedance does not exceed 0.1, the lumped-element model always predicts responses within 1% of those for the transmission-line model.

  11. Generalized transmission line method to study the far-zone radiation of antennas under a multilayer structure

    CERN Document Server

    Wu, Xuan Hui

    2008-01-01

    This book gives a step-by-step presentation of a generalized transmission line method to study the far-zone radiation of antennas under a multilayer structure. Normally, a radiation problem requires a full wave analysis which may be time consuming. The beauty of the generalized transmission line method is that it transforms the radiation problem for a specific type of structure, say the multilayer structure excited by an antenna, into a circuit problem that can be efficiently analyzed. Using the Reciprocity Theorem and far-field approximation, the method computes the far-zone radiation due to

  12. Residual life assessment of overhead transmission lines 110 kV and above and determination of their reconstruction terms

    Directory of Open Access Journals (Sweden)

    Uteuliyev Bauyrzhan

    2017-01-01

    Full Text Available In this article is given a method for assessment the residual life of overhead transmission lines on reinforced concrete supports with centrifuged poles. Reinforced concrete poles of supports, wires and lightning protection cables are adopted as the main elements. The intensity of change in the actual state parameters of these elements is determined by the laws of random variables distribution that allow predicting the residual life and the timing of repairs and reconstruction of overhead transmission lines. The parameters of natural climatic conditions and other external factors are considered by including of coefficients into the formula for changing the actual state parameters.

  13. Long term investigation of thermal behaviour of 110 kV underground transmission lines in the Belgrade area

    Energy Technology Data Exchange (ETDEWEB)

    Sredojevic, M.R.; Naumov, R.M.; Popovic, D.P. [Nikola Tesla Electrical Engineering Inst., Belgrade (Yugoslavia); Simic, M.D. [Electrical Utility Co., Belgrade (Yugoslavia)

    1997-12-31

    The paper describes the procedure for applying a special cable backfill material, developed and manufactured at the Institute ``Nikola Tesla`` for the thermal stabilisation and reduction of hot spot cable operating temperature, on specific hot spots of 110 kV underground transmission lines in the Belgrade area. The results presented in this paper are an important contribution to the proof of the justification and necessity of defining and introducing in practice new procedures for the thermal stabilisation and reduction of operating temperature of existing, as well as of new, underground transmission cable lines to be built. (author)

  14. LHC dipole magnets start to roll off the production line

    CERN Multimedia

    2000-01-01

    The first pre-series LHC dipole magnet has been delivered to CERN, a further 1247 are due to be produced by 2005. Their production is the result of technology transfer from CERN to its suppliers. Fifteen metres long, thirty-tonnes in weight, and using several kilometres of superconducting cable, the magnet that has just arrived in hall 181 is a true colossus. It is the first pre-series dipole that will begin service in 2005 in the future Large Hadron Collider, LHC. Delivered by the French Alstom-Jeumont Industrie consortium, it is the first of 1248 magnets that will be manufactured over the coming five years. Needless to say, lavish attention has been devoted to this magnet by the engineers and technicians who accompanied it to CERN from Belfort in north east France. The task of the dipole magnets will be to steer the LHC's proton beams on a circular trajectory around the LHC's 27 kilometre circumference. A magnetic field of 8.33 Tesla is required to guide the protons, accelerated to an energy of 7 TeV, aroun...

  15. Cross Talk Analysis on Multiple Coupled Transmission Lines; (The calculation of transfer functions on multiple coupled tansmission lines in an inhomogeneous dielectric medium)

    DEFF Research Database (Denmark)

    Dalby, Arne Brejning

    1994-01-01

    A flow graph relating voltages and the forward and reflected propagation modes (¿ TEM) on multiple coupled transmission lines in an inhomogeneous dielectric medium is presented. This flow graph directy gives the different transfer functions, including S-parameters, in matrix form needed to calcul......A flow graph relating voltages and the forward and reflected propagation modes (¿ TEM) on multiple coupled transmission lines in an inhomogeneous dielectric medium is presented. This flow graph directy gives the different transfer functions, including S-parameters, in matrix form needed...... to calculate crosstalk on the lines. An 8 bit databus is analysed in the frequency-and time domain. This analysis shows, as expected, that crosstalk can be a problem in connection with high speed logic circuits. The same databus is also analysed using the quasi-propagation-mode method proposed by Dalby [1...

  16. A Novel Method of Autonomous Inspection for Transmission Line based on Cable Inspection Robot LiDAR Data

    Directory of Open Access Journals (Sweden)

    Xinyan Qin

    2018-02-01

    Full Text Available With the growth of the national economy, there is increasing demand for electricity, which forces transmission line corridors to become structurally complicated and extend to complex environments (e.g., mountains, forests. It is a great challenge to inspect transmission line in these regions. To address these difficulties, a novel method of autonomous inspection for transmission line is proposed based on cable inspection robot (CIR LiDAR data, which mainly includes two steps: preliminary inspection and autonomous inspection. In preliminary inspection, the position and orientation system (POS data is used for original point cloud dividing, ground point filtering, and structured partition. A hierarchical classification strategy is established to identify the classes and positions of the abnormal points. In autonomous inspection, CIR can autonomously reach the specified points through inspection planning. These inspection targets are imaged with PTZ (pan, tilt, zoom cameras by coordinate transformation. The feasibility and effectiveness of the proposed method are verified by test site experiments and actual line experiments, respectively. The proposed method greatly reduces manpower and improves inspection accuracy, providing a theoretical basis for intelligent inspection of transmission lines in the future.

  17. A Novel Method of Autonomous Inspection for Transmission Line based on Cable Inspection Robot LiDAR Data.

    Science.gov (United States)

    Qin, Xinyan; Wu, Gongping; Lei, Jin; Fan, Fei; Ye, Xuhui; Mei, Quanjie

    2018-02-15

    With the growth of the national economy, there is increasing demand for electricity, which forces transmission line corridors to become structurally complicated and extend to complex environments (e.g., mountains, forests). It is a great challenge to inspect transmission line in these regions. To address these difficulties, a novel method of autonomous inspection for transmission line is proposed based on cable inspection robot (CIR) LiDAR data, which mainly includes two steps: preliminary inspection and autonomous inspection. In preliminary inspection, the position and orientation system (POS) data is used for original point cloud dividing, ground point filtering, and structured partition. A hierarchical classification strategy is established to identify the classes and positions of the abnormal points. In autonomous inspection, CIR can autonomously reach the specified points through inspection planning. These inspection targets are imaged with PTZ (pan, tilt, zoom) cameras by coordinate transformation. The feasibility and effectiveness of the proposed method are verified by test site experiments and actual line experiments, respectively. The proposed method greatly reduces manpower and improves inspection accuracy, providing a theoretical basis for intelligent inspection of transmission lines in the future.

  18. Time Ordering Effects on Hydrogen Zeeman-Stark Line Profiles in Low-Density Magnetized Plasmas

    Directory of Open Access Journals (Sweden)

    J. Rosato

    2010-01-01

    Full Text Available Stark broadening of hydrogen lines is investigated in low-density magnetized plasmas, at typical conditions of magnetic fusion experiments. The role of time ordering is assessed numerically, by using a simulation code accounting for the evolution of the microscopic electric field generated by the charged particles moving at the vicinity of the atom. The Zeeman effect due to the magnetic field is also retained. Lyman lines with a low principal quantum number n are first investigated, for an application to opacity calculations; next Balmer lines with successively low and high principal quantum numbers are considered for diagnostic purposes. It is shown that neglecting time ordering results in a dramatic underestimation of the Stark effect on the low-n lines. Another conclusion is that time ordering becomes negligible only when ion dynamics effects vanish, as shown in the case of high-n lines.

  19. Transmission line pulse system for avalanche characterization of high power semiconductor devices

    Science.gov (United States)

    Riccio, Michele; Ascione, Giovanni; De Falco, Giuseppe; Maresca, Luca; De Laurentis, Martina; Irace, Andrea; Breglio, Giovanni

    2013-05-01

    Because of the increasing in power density of electronic devices for medium and high power application, reliabilty of these devices is of great interest. Understanding the avalanche behaviour of a power device has become very important in these last years because it gives an indication of the maximum energy ratings which can be seen as an index of the device ruggedness. A good description of this behaviour is given by the static IV blocking characteristc. In order to avoid self heating, very relevant in high power devices, very short pulses of current have to be used, whose value can change from few milliamps up to tens of amps. The most used method to generate short pulses is the TLP (Transmission Line Pulse) test, which is based on charging the equivalent capacitance of a transmission line to high value of voltage and subsequently discharging it onto a load. This circuit let to obtain very short square pulses but it is mostly used for evaluate the ESD capability of semiconductor and, in this environment, it generates pulses of low amplitude which are not high enough to characterize the avalanche behaviour of high power devices . Advanced TLP circuit able to generate high current are usually very expensive and often suffer of distorption of the output pulse. In this article is proposed a simple, low cost circuit, based on a boosted-TLP configuration, which is capable to produce very square pulses of about one hundreds of nanosecond with amplitude up to some tens of amps. A prototype is implemented which can produce pulses up to 20A of amplitude with 200 ns of duration which can characterize power devices up to 1600V of breakdown voltage. Usage of microcontroller based logic make the circuit very flexible. Results of SPICE simulation are provided, together with experimental results. To prove the effectiveness of the circuit, the I-V blocking characteristics of two commercial devices, namely a 600V PowerMOS and a 1200V Trench-IGBT, are measured at different

  20. Mechanical Implementation and Simulation of MoboLab, A Mobile Robot for Inspection of Power Transmission Lines

    Directory of Open Access Journals (Sweden)

    Mahmud Saadat Foumani

    2008-11-01

    Full Text Available This paper describes the first phase in development of a mobile robot that can navigate aerial power transmission lines completely unattended by human operator. Its ultimate purpose is to automate inspection of power transmission lines and their equipments. The authors have developed a scaled functional model of such a mobile robot with a preliminary simple computer based on-off controller. MoboLab (Mobile Laboratory navigates a power transmission line between two strain towers. It can maneuver over obstructions created by line equipments such as insulators, warning spheres, dampers, and spacer dampers. It can also easily negotiate the towers by its three flexible arms. MoboLab has an internal main screw which enables the robot to move itself or its two front and rear arms independently through changing gripped points. When the front arm gets close to an obstacle, the arm detaches from the line and goes down, the robot moves forward, the arm passes the obstacle and grippes the line again. In a same way another arms pass the obstacle.

  1. Infrared lines as probes of solar magnetic features. VIII. Mg I 12 micron diagnostics of sunspots

    NARCIS (Netherlands)

    Bruls, J.H.M.J.; Solanki, S.K.; Rutten, R.J.; Carlsson, M.

    1995-01-01

    Due to their large Zeeman sensitivity, the MgI lines at 12μm are important diagnostics of solar magnetism. The formation of their central emission features is now understood, enabling quantitative modeling and diagnostic application of these lines. We supply the first systematic analysis of solar

  2. A method for assessing occupational exposure to power-frequency magnetic fields for electricity generation and transmission workers

    International Nuclear Information System (INIS)

    Renew, D C; Cook, R F; Ball, M C

    2003-01-01

    A new method for assessing both current and historical occupational exposures to magnetic fields has been developed and used in health studies involving a cohort of electricity generation and transmission workers in England and Wales. The exposure values are derived by calculation from engineering and operational data about the power stations rather than from measurements. They are provided for each of 11 job categories for each year of operation of each power station represented in the cohort. The engineering data are used to determine the average magnetic fields in specified areas of work within the power station and then applied to information about the time spent in these areas by each of the job categories. The operational data are used to adjust the exposures for each year according to the power station output for the year. Earlier methods used measurements or the advice of panels of experts to provide exposure scores for a number of job categories across all power stations and years. Such methods were not able to distinguish exposures from different power facilities or during the different years of their operation. Measurement surveys at 10 power stations of the magnetic fields in the work areas gave confidence that the calculations were realistic. Exposure measurements on 215 workers at three power stations were compared in job groups with the exposures predicted by the method. The Pearson correlation coefficient was 0.86 and the slope and intercept of the line of best fit were 0.87 and 0.07 μT respectively. The method gives a good prediction of measured exposure and is being used for studies of occupational exposure to magnetic fields and leukaemia, and of cardiovascular disease, and a reanalysis of brain cancer

  3. A Line Weighted Frequency Droop Controller for Decentralized Enforcement of Transmission Line Power Flow Constraints in Inverter-Based Networks

    Energy Technology Data Exchange (ETDEWEB)

    Ainsworth, Nathan G [ORNL; Grijalva, Prof. Santiago [Georgia Institute of Technology, Atlanta

    2013-01-01

    Recent works have shown that networks of voltagesource inverters implementing frequency droop control may be analyzed as consensus-like networks. Based on this understanding, we show that enforcement of network line power flows can be viewed as an edge-preservation problem in a -disk dynamic interaction graph. Inspired by other works solving similar problems in other domains, we propose a line weighted frequency droop controller such that a network of all active buses implementing this controller enforces the specified line power flow constraints without need for communication. We provide simulation results verifying that our proposed controller limits line power to enforce constraints, and otherwise acts as a traditional droop controller.

  4. An ME-PC Enhanced HDMR Method for Efficient Statistical Analysis of Multiconductor Transmission Line Networks

    KAUST Repository

    Yucel, Abdulkadir C.

    2015-05-05

    An efficient method for statistically characterizing multiconductor transmission line (MTL) networks subject to a large number of manufacturing uncertainties is presented. The proposed method achieves its efficiency by leveraging a high-dimensional model representation (HDMR) technique that approximates observables (quantities of interest in MTL networks, such as voltages/currents on mission-critical circuits) in terms of iteratively constructed component functions of only the most significant random variables (parameters that characterize the uncertainties in MTL networks, such as conductor locations and widths, and lumped element values). The efficiency of the proposed scheme is further increased using a multielement probabilistic collocation (ME-PC) method to compute the component functions of the HDMR. The ME-PC method makes use of generalized polynomial chaos (gPC) expansions to approximate the component functions, where the expansion coefficients are expressed in terms of integrals of the observable over the random domain. These integrals are numerically evaluated and the observable values at the quadrature/collocation points are computed using a fast deterministic simulator. The proposed method is capable of producing accurate statistical information pertinent to an observable that is rapidly varying across a high-dimensional random domain at a computational cost that is significantly lower than that of gPC or Monte Carlo methods. The applicability, efficiency, and accuracy of the method are demonstrated via statistical characterization of frequency-domain voltages in parallel wire, interconnect, and antenna corporate feed networks.

  5. Compact Single-Layer Traveling-Wave Antenna DesignUsing Metamaterial Transmission Lines

    Science.gov (United States)

    Alibakhshikenari, Mohammad; Virdee, Bal Singh; Limiti, Ernesto

    2017-12-01

    This paper presents a single-layer traveling-wave antenna (TWA) that is based on composite right/left-handed (CRLH)-metamaterial (MTM) transmission line (TL) structure, which is implemented by using a combination of interdigital capacitors and dual-spiral inductive slots. By embedding dual-spiral inductive slots inside the CRLH MTM-TL results in a compact TWA. Dimensions of the proposed CRLH MTM-TL TWA is 21.5 × 30.0 mm2 or 0.372λ0 × 0.520λ0 at 5.2 GHz (center frequency). The fabricated TWA operates over 1.8-8.6 GHz with a fractional bandwidth greater than 120%, and it exhibits a peak gain and radiation efficiency of 4.2 dBi and 81%, respectively, at 5 GHz. By avoiding the use of lumped components, via-holes or defected ground structures, the proposed TWA design is economic for mass production as well as easy to integrate with wireless communication systems.

  6. New Keypoint Matching Method Using Local Convolutional Features for Power Transmission Line Icing Monitoring

    Directory of Open Access Journals (Sweden)

    Qiangliang Guo

    2018-02-01

    Full Text Available Power transmission line icing (PTLI problems, which cause tremendous damage to the power grids, has drawn much attention. Existing three-dimensional measurement methods based on binocular stereo vision was recently introduced to measure the ice thickness in PTLI, but failed to meet requirements of practical applications due to inefficient keypoint matching in the complex PTLI scene. In this paper, a new keypoint matching method is proposed based on the local multi-layer convolutional neural network (CNN features, termed Local Convolutional Features (LCFs. LCFs are deployed to extract more discriminative features than the conventional CNNs. Particularly in LCFs, a multi-layer features fusion scheme is exploited to boost the matching performance. Together with a location constraint method, the correspondence of neighboring keypoints is further refined. Our approach achieves 1.5%, 5.3%, 13.1%, 27.3% improvement in the average matching precision compared with SIFT, SURF, ORB and MatchNet on the public Middlebury dataset, and the measurement accuracy of ice thickness can reach 90.9% compared with manual measurement on the collected PTLI dataset.

  7. Self-consistent nonlinear transmission line model of standing wave effects in a capacitive discharge

    International Nuclear Information System (INIS)

    Chabert, P.; Raimbault, J.L.; Rax, J.M.; Lieberman, M.A.

    2004-01-01

    It has been shown previously [Lieberman et al., Plasma Sources Sci. Technol. 11, 283 (2002)], using a non-self-consistent model based on solutions of Maxwell's equations, that several electromagnetic effects may compromise capacitive discharge uniformity. Among these, the standing wave effect dominates at low and moderate electron densities when the driving frequency is significantly greater than the usual 13.56 MHz. In the present work, two different global discharge models have been coupled to a transmission line model and used to obtain the self-consistent characteristics of the standing wave effect. An analytical solution for the wavelength λ was derived for the lossless case and compared to the numerical results. For typical plasma etching conditions (pressure 10-100 mTorr), a good approximation of the wavelength is λ/λ 0 ≅40 V 0 1/10 l -1/2 f -2/5 , where λ 0 is the wavelength in vacuum, V 0 is the rf voltage magnitude in volts at the discharge center, l is the electrode spacing in meters, and f the driving frequency in hertz

  8. Analysis and Measurements of 170 GHz ITER ECH Transmission Line Components

    Science.gov (United States)

    Jawla, Sudheer; Schaub, Samuel; Shapiro, Michael; Kowalski, Elizabeth; Temkin, Richard; Hanson, Gregory

    2014-10-01

    In this paper we discuss two important issues related to the ITER 170 GHz ECH 63.5-mm diameter corrugated waveguide Transmission Lines (TL); 1) calculation of mode conversion losses in the expansion units for the TL, and, 2) determination of mode contents in corrugated waveguides. Expansion units are needed to accommodate expansion and contraction along the TL from the gyrotron to the tokamak. A numerical mode matching code has been developed to estimate power losses due to mode conversion of the operating mode, HE11, to higher order modes as a result of the radial discontinuities in a sliding joint. Two designs were evaluated, a simple gap expansion unit and a more complex tapered expansion unit. We also present a novel method for determining the mode content of the linearly polarized (LP) modes of a corrugated waveguide using the method of moments. This method is based on calculating the low order irradiance moments of the measured radiated intensity profiles at several distances from the waveguide aperture. The proposed method is experimentally validated by the data measured from the 63.5-mm diameter corrugated waveguide using the vector network analyzer and a high purity HE11 mode generator at 170 GHz built by General Atomics. This research was supported by the U.S. Department of Energy, Office of Fusion Energy Sciences and by the U.S. ITER Project managed by Battelle/Oak Ridge National Laboratory.

  9. Autonomous Inspection Robot for Power Transmission Lines Maintenance While Operating on the Overhead Ground Wires

    Directory of Open Access Journals (Sweden)

    Zheng Li

    2010-12-01

    Full Text Available This paper describes the development of a mobile robot capable of clearing such obstacles as counterweights, anchor clamps, and torsion tower. The mobile robot walks on overhead ground wires in 500KV power tower. Its ultimate purpose is to automate to inspect the defect of power transmission line. The robot with 13 motors is composed of two arms, two wheels, two claws, two wrists, etc. Each arm has 4 degree of freedom. Claws are also mounted on the arms. An embedded computer based on PC/104 is chosen as the core of control system. Visible light and thermal infrared cameras are installed to obtain the video and temperature information, and the communication system is based on wireless LAN TCP/IP protocol. A prototype robot was developed with careful considerations of mobility. The new sensor configuration is used for the claw to grasp the overhead ground wires. The bridge is installed in the torsion tower for the robot easy to cross obstacles. The new posture plan is proposed for obstacles cleaning in the torsion tower. Results of experiments demonstrate that the robot can be applied to execute the navigation and inspection tasks.

  10. Autonomous Inspection Robot for Power Transmission Lines Maintenance While Operating on the Overhead Ground Wires

    Directory of Open Access Journals (Sweden)

    Zheng Li

    2011-01-01

    Full Text Available This paper describes the development of a mobile robot capable of clearing such obstacles as counterweights, anchor clamps, and torsion tower. The mobile robot walks on overhead ground wires in 500KV power tower. Its ultimate purpose is to automate to inspect the defect of power transmission line. The robot with 13 motors is composed of two arms, two wheels, two claws, two wrists, etc. Each arm has 4 degree of freedom. Claws are also mounted on the arms. An embedded computer based on PC/104 is chosen as the core of control system. Visible light and thermal infrared cameras are installed to obtain the video and temperature information, and the communication system is based on wireless LAN TCP/IP protocol. A prototype robot was developed with careful considerations of mobility. The new sensor configuration is used for the claw to grasp the overhead ground wires. The bridge is installed in the torsion tower for the robot easy to cross obstacles. The new posture plan is proposed for obstacles cleaning in the torsion tower. Results of experiments demonstrate that the robot can be applied to execute the navigation and inspection tasks.

  11. Development of data acquisition and control system for ICH & CD transmission line components test facility

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Manoj, E-mail: manoj.patel@iter-india.org [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar 382428, Gujarat (India); Jha, Akhil [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar 382428, Gujarat (India); Patel, Nidhi [Department of Instrumentation & Control Engineering, Dharmsinh Desai University, Nadiad 387001, Gujarat (India); Krishna, J.V.S. Hari; Rajnish, Kumar; Soni, Dipal; Verma, Sriprakash; Patel, Hriday; Trivedi, Rajesh; Mukherjee, Aparajita [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar 382428, Gujarat (India)

    2016-11-15

    Highlights: • Traveling Wave Resonator (TWR) gain achieved is 13.58 dB using 10 dB coupler. • Software module for Automatic calibration for power detector is developed and integrated. • Application module is developed using LabVIEW™ for high power RF operation of TWR. - Abstarct: India is developing a very high power test bed (∼MW level) based on concept of Travelling Wave Resonator (TWR) for testing of passive transmission line components [3]. Data acquisition and control system is required for safe and reliable operation of TWR. It includes online monitoring of input power and circulating ring power. Acquired RF signal provides information about forward and reflected RF power. For MW power level testing, system is protected against arc and thermal effect during CW operation. National Instrument make hardware and software have been used to acquire signals from RF detector, Arc detectors, IR camera and thermocouples etc. LabVIEW™ based software has been developed for calculation of RF parameters. Graphical user interface is developed for better visualization. Initial testing of the TWR setup with 10 dB coupler provides a power gain of 13.58 dB (22X). For future 3 MW TWR test bed the required power gain is ∼20 dB (100X) since the available source is ∼40 kW. This paper describes the detail design and integrated test results for data acquisition and control system for TWR test bed.

  12. Superconducting qubit in a nonstationary transmission line cavity: Parametric excitation, periodic pumping, and energy dissipation

    Energy Technology Data Exchange (ETDEWEB)

    Zhukov, A.A. [N.L. Dukhov All-Russia Research Institute of Automatics, 127055 Moscow (Russian Federation); National Research Nuclear University (MEPhI), 115409 Moscow (Russian Federation); Shapiro, D.S., E-mail: shapiro.dima@gmail.com [N.L. Dukhov All-Russia Research Institute of Automatics, 127055 Moscow (Russian Federation); V.A. Kotel' nikov Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 125009 Moscow (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700 (Russian Federation); National University of Science and Technology MISIS, 119049 Moscow (Russian Federation); Remizov, S.V. [N.L. Dukhov All-Russia Research Institute of Automatics, 127055 Moscow (Russian Federation); V.A. Kotel' nikov Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 125009 Moscow (Russian Federation); Pogosov, W.V. [N.L. Dukhov All-Russia Research Institute of Automatics, 127055 Moscow (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700 (Russian Federation); Institute for Theoretical and Applied Electrodynamics, Russian Academy of Sciences, 125412 Moscow (Russian Federation); Lozovik, Yu.E. [N.L. Dukhov All-Russia Research Institute of Automatics, 127055 Moscow (Russian Federation); National Research Nuclear University (MEPhI), 115409 Moscow (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700 (Russian Federation); Institute of Spectroscopy, Russian Academy of Sciences, 142190 Moscow Region, Troitsk (Russian Federation)

    2017-02-12

    We consider a superconducting qubit coupled to the nonstationary transmission line cavity with modulated frequency taking into account energy dissipation. Previously, it was demonstrated that in the case of a single nonadiabatical modulation of a cavity frequency there are two channels of a two-level system excitation which are due to the absorption of Casimir photons and due to the counterrotating wave processes responsible for the dynamical Lamb effect. We show that the parametric periodical modulation of the resonator frequency can increase dramatically the excitation probability. Remarkably, counterrotating wave processes under such a modulation start to play an important role even in the resonant regime. Our predictions can be used to control qubit-resonator quantum states as well as to study experimentally different channels of a parametric qubit excitation. - Highlights: • Coupled qubit-resonator system under the modulation of a resonator frequency is considered. • Counterrotating terms of the Hamiltonian are of importance even in the resonance. • Qubit excited state population is highest if driving frequency matches dressed-state energy.

  13. Acoustical transmission-line model of the middle-ear cavities and mastoid air cells.

    Science.gov (United States)

    Keefe, Douglas H

    2015-04-01

    An acoustical transmission line model of the middle-ear cavities and mastoid air cell system (MACS) was constructed for the adult human middle ear with normal function. The air-filled cavities comprised the tympanic cavity, aditus, antrum, and MACS. A binary symmetrical airway branching model of the MACS was constructed using an optimization procedure to match the average total volume and surface area of human temporal bones. The acoustical input impedance of the MACS was calculated using a recursive procedure, and used to predict the input impedance of the middle-ear cavities at the location of the tympanic membrane. The model also calculated the ratio of the acoustical pressure in the antrum to the pressure in the middle-ear cavities at the location of the tympanic membrane. The predicted responses were sensitive to the magnitude of the viscothermal losses within the MACS. These predicted input impedance and pressure ratio functions explained the presence of multiple resonances reported in published data, which were not explained by existing MACS models.

  14. Simulation of the space charge near coronating conductors of ac overhead transmission lines

    International Nuclear Information System (INIS)

    Straumann, Ueli

    2011-01-01

    In the case of ac high voltage overhead transmission lines, corona discharges may result in a broadband crackling and a humming noise at twice the mains frequency (2f). The computation of the emitted 2f-levels presupposes the knowledge of the apparent power and force passed by the ions to the gas in the surroundings of the conductors. In this paper a simulation determining these magnitudes used in a previous publication is presented. For that purpose the ideas of earlier publications by other authors to compute corona losses are followed. Their central idea is to define an onset field strength on the surface of the conductor which is not exceeded by injecting the right amount of charges in the vicinity of the conductor. This injection together with the recombination determines the amount of drifting ions. The novelty of the method applied in this work is the consideration of different onset field strengths over the conductor surface in dependence of the polar angle. Further 2f-force and 2f-power acting on the gas in the vicinity of the conductor are determined out of the resulting ion drift. The corona currents thus computed coincide fairly well with measured results.

  15. Simulation of the space charge near coronating conductors of ac overhead transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Straumann, Ueli, E-mail: stulrich@ethz.ch [High Voltage Laboratory, ETH Zurich, CH-8092 Zuerich (Switzerland)

    2011-02-23

    In the case of ac high voltage overhead transmission lines, corona discharges may result in a broadband crackling and a humming noise at twice the mains frequency (2f). The computation of the emitted 2f-levels presupposes the knowledge of the apparent power and force passed by the ions to the gas in the surroundings of the conductors. In this paper a simulation determining these magnitudes used in a previous publication is presented. For that purpose the ideas of earlier publications by other authors to compute corona losses are followed. Their central idea is to define an onset field strength on the surface of the conductor which is not exceeded by injecting the right amount of charges in the vicinity of the conductor. This injection together with the recombination determines the amount of drifting ions. The novelty of the method applied in this work is the consideration of different onset field strengths over the conductor surface in dependence of the polar angle. Further 2f-force and 2f-power acting on the gas in the vicinity of the conductor are determined out of the resulting ion drift. The corona currents thus computed coincide fairly well with measured results.

  16. Coronal Heating Topology: The Interplay of Current Sheets and Magnetic Field Lines

    International Nuclear Information System (INIS)

    Rappazzo, A. F.; Velli, M.; Matthaeus, W. H.; Ruffolo, D.; Servidio, S.

    2017-01-01

    The magnetic topology and field line random walk (FLRW) properties of a nanoflare-heated and magnetically confined corona are investigated in the reduced magnetohydrodynamic regime. Field lines originating from current sheets form coherent structures, called current sheet connected (CSC) regions, which extend around them. CSC FLRW is strongly anisotropic, with preferential diffusion along the current sheets’ in-plane length. CSC FLRW properties remain similar to those of the entire ensemble but exhibit enhanced mean square displacements and separations due to the stronger magnetic field intensities in CSC regions. The implications for particle acceleration and heat transport in the solar corona and wind, and for solar moss formation are discussed.

  17. Coronal Heating Topology: The Interplay of Current Sheets and Magnetic Field Lines

    Energy Technology Data Exchange (ETDEWEB)

    Rappazzo, A. F.; Velli, M. [Department of Earth, Planetary, and Space Sciences, UCLA, Los Angeles, CA 90095 (United States); Matthaeus, W. H. [Bartol Research Institute, Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); Ruffolo, D. [Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand); Servidio, S., E-mail: rappazzo@ucla.edu [Dipartimento di Fisica, Università della Calabria, Cosenza I-87036 (Italy)

    2017-07-20

    The magnetic topology and field line random walk (FLRW) properties of a nanoflare-heated and magnetically confined corona are investigated in the reduced magnetohydrodynamic regime. Field lines originating from current sheets form coherent structures, called current sheet connected (CSC) regions, which extend around them. CSC FLRW is strongly anisotropic, with preferential diffusion along the current sheets’ in-plane length. CSC FLRW properties remain similar to those of the entire ensemble but exhibit enhanced mean square displacements and separations due to the stronger magnetic field intensities in CSC regions. The implications for particle acceleration and heat transport in the solar corona and wind, and for solar moss formation are discussed.

  18. Schemes of high-voltage pulse shapers on the basics of stepped transmission lines for high-current accelerators

    International Nuclear Information System (INIS)

    Gordeev, V.S.

    1999-01-01

    In the course of creating high current linear induction accelerators (LIA) there was developed a new type of multi-cascade high-voltage pulse generators designed of homogeneous transmission lines of equal electric length. The examples of different-type schemes of capacitive generator inductive generator and inductive-capacitate type generator are given

  19. Broadband Butler Matrices with the Use of High-Pass LC Sections as Left-Handed Transmission Lines

    Directory of Open Access Journals (Sweden)

    K. Staszek

    2014-04-01

    Full Text Available An application of left-handed transmission line sections in Butler matrices has been investigated. It has been shown, for the first time, that the utilization of both left-handed and right-handed transmission lines allows for broadband differential phase shifters’ realization, required in the Butler matrices. A complete theoretical analysis is given, for Butler matrices incorporating ideal transmission lines of both right- and left handed types and expressions for the achievable bandwidth and differential phase deviation are derived. The presented idea has been verified by the design of a 4 x 4 Butler matrix operating in a frequency range of 2.5 – 3.5 GHz. As an artificial left-handed transmission line, an equivalent high-pass LC circuit realized in a quasi-lumped element technique, has been considered, and the resulting phase shift of such a circuit is given analytically. The obtained measurement results fully confirm the validity of the proposed idea of broadband Butler matrices’ realization.

  20. A Broad Iron Line in the Chandra High Energy Transmission Grating Spectrum of 4U 1705-44

    NARCIS (Netherlands)

    di Salvo, T.; Iaria, R.; Méndez, R.M.; Burderi, L.; Lavagetto, G.; Robba, N.R.; Stella, L.; van der Klis, M.

    2005-01-01

    We present the results of a Chandra 30 ks observation of the low-mass X-ray binary and atoll source 4U 1705-44. Here we concentrate on the study of discrete features in the energy spectrum at energies below ~3 keV, as well as on the iron Kalpha line, using the High Energy Transmission Grating