Propagation of 1-THz bandwidth electrical pulses on high Tc superconducting transmission lines

International Nuclear Information System (INIS)

Nuss, M.C.; Mankiewich, P.M.; Howard, R.E.; Harvey, T.E.; Brandle, C.D.; Straugh, B.L.; Smith, P.R.

1989-01-01

The new high temperature superconductors have triggered enormous interest not only because of the unique physics involved but also because of their technical potentials, such as the promise for propagation of extremely short electrical pulses. Superconducting band caps of --20TH z are predicted assuming BCS theory for the superconductor, making lossless propagation of electrical pulses as short as 50 fs possible. Despite microwave measurements at low frequencies of several gigahertz first studies at higher frequencies by Dykaar et al have shown distortion-free propagation of 100-GHz electrical pulses on YBa 2 Cu 3 O 3 (YBCO) lines for --5-mm propagation distance. Results were also reported for aluminum coplanar lines and a YBCO ground plane. The authors report on the propagation of 1-ps electrical pulses (1-THz bandwidth) on YBCO coplanar transmission lines defined on lanthanum gallate (LaGaO 3 ) as a substrate. On LaGaO 3 , YBCO grows highly oriented as on SrTiO 3 . However, unlike SrTiO 3 , LaGaO 3 has a much lower dielectric constant and small losses in the terahertz frequency range. Electrical pulses of --750-fs duration are generated in a radiation-damaged silicon-on-sapphire photoconductive switch integrated into a 20-μm coplanar stripline with 10-μm spacing and excited with 100-fs optical pulses from a CPM laser. An μ1-THz bandwidth electrical contact is made to the YBCO coplanar stripline defined on LaGaO 3 using a flip-chip geometry. They find that electrical pulses broaden only from 750 fs to 1 ps with little loss in amplitude on traveling through their flip-chip input and propagated electrical pulses are probed by electooptic sampling in two small LiTaO 3 crystals separated by 3 mm

Comparative cost study of the processes for producing niobium--tin (Nb3Sn) superconducting tapes for their application to power transmission lines. Final report

International Nuclear Information System (INIS)

1976-10-01

This report considers the manufacture of superconducting Nb 3 Sn tapes for ac superconducting transmission cables. The 14 product examples studied are produced by processes involving solid-state diffusion of Sn and Nb and/or physical vapor deposition. Production of 80,000 km per year is assumed, sufficient for 100 km of 3 phase ac line. Results are summarized in a table entitled ''Variants of 6 mm wide Nb 3 Sn Superconducting Tapes with Economics of Manufacture.'' The table identifies the 14 product examples by method of manufacture; by the composition of the layers integrated into the tape; and by the final thickness of Nb used in 12 of the product examples. The estimated fixed capital for plant is listed for each product example together with the estimated costs of manufacture in cents per meter of tape. The total manufacturing cost given is the sum of the costs of raw materials, operating labor, depreciation and other overhead. The depreciation is calculated on a 10 year straight line basis. Stainless steel strip (304L) is used in 6 of the product examples. The final line in the table shows the ''selling price'' which will earn the equivalent of 20 percent p.a. on the total capital, fixed and working, employed at any time during an eleven-year plant life where depreciation is sum of year digits for a 10 year period, investment credit is 10 percent, and income tax is 48 percent. 13 tables, 21 figures

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.

Performance analysis of a model-sized superconducting DC transmission system based VSC-HVDC transmission technologies using RTDS

International Nuclear Information System (INIS)

Dinh, Minh-Chau; Ju, Chang-Hyeon; Kim, Sung-Kyu; Kim, Jin-Geun; Park, Minwon; Yu, In-Keun

2012-01-01

The combination of a high temperature superconducting DC power cable and a voltage source converter based HVDC (VSC-HVDC) creates a new option for transmitting power with multiple collection and distribution points for long distance and bulk power transmissions. It offers some greater advantages compared with HVAC or conventional HVDC transmission systems, and it is well suited for the grid integration of renewable energy sources in existing distribution or transmission systems. For this reason, a superconducting DC transmission system based HVDC transmission technologies is planned to be set up in the Jeju power system, Korea. Before applying this system to a real power system on Jeju Island, system analysis should be performed through a real time test. In this paper, a model-sized superconducting VSC-HVDC system, which consists of a small model-sized VSC-HVDC connected to a 2 m YBCO HTS DC model cable, is implemented. The authors have performed the real-time simulation method that incorporates the model-sized superconducting VSC-HVDC system into the simulated Jeju power system using Real Time Digital Simulator (RTDS). The performance analysis of the superconducting VSC-HVDC systems has been verified by the proposed test platform and the results were discussed in detail.

Performance analysis of a model-sized superconducting DC transmission system based VSC-HVDC transmission technologies using RTDS

Energy Technology Data Exchange (ETDEWEB)

Dinh, Minh-Chau, E-mail: thanchau7787@gmail.com [Changwon National University, 9 Sarim-Dong, Changwon 641-733 (Korea, Republic of); Ju, Chang-Hyeon; Kim, Sung-Kyu; Kim, Jin-Geun; Park, Minwon [Changwon National University, 9 Sarim-Dong, Changwon 641-733 (Korea, Republic of); Yu, In-Keun, E-mail: yuik@changwon.ac.kr [Changwon National University, 9 Sarim-Dong, Changwon 641-733 (Korea, Republic of)

2012-08-15

The combination of a high temperature superconducting DC power cable and a voltage source converter based HVDC (VSC-HVDC) creates a new option for transmitting power with multiple collection and distribution points for long distance and bulk power transmissions. It offers some greater advantages compared with HVAC or conventional HVDC transmission systems, and it is well suited for the grid integration of renewable energy sources in existing distribution or transmission systems. For this reason, a superconducting DC transmission system based HVDC transmission technologies is planned to be set up in the Jeju power system, Korea. Before applying this system to a real power system on Jeju Island, system analysis should be performed through a real time test. In this paper, a model-sized superconducting VSC-HVDC system, which consists of a small model-sized VSC-HVDC connected to a 2 m YBCO HTS DC model cable, is implemented. The authors have performed the real-time simulation method that incorporates the model-sized superconducting VSC-HVDC system into the simulated Jeju power system using Real Time Digital Simulator (RTDS). The performance analysis of the superconducting VSC-HVDC systems has been verified by the proposed test platform and the results were discussed in detail.

Optical transmission modules for multi-channel superconducting quantum interference device readouts

Energy Technology Data Exchange (ETDEWEB)

Kim, Jin-Mok, E-mail: jmkim@kriss.re.kr; Kwon, Hyukchan; Yu, Kwon-kyu; Lee, Yong-Ho; Kim, Kiwoong [Brain Cognition Measurement Center, Korea Research Institute of Standards and Science, Daejeon 305-600 (Korea, Republic of)

2013-12-15

We developed an optical transmission module consisting of 16-channel analog-to-digital converter (ADC), digital-noise filter, and one-line serial transmitter, which transferred Superconducting Quantum Interference Device (SQUID) readout data to a computer by a single optical cable. A 16-channel ADC sent out SQUID readouts data with 32-bit serial data of 8-bit channel and 24-bit voltage data at a sample rate of 1.5 kSample/s. A digital-noise filter suppressed digital noises generated by digital clocks to obtain SQUID modulation as large as possible. One-line serial transmitter reformed 32-bit serial data to the modulated data that contained data and clock, and sent them through a single optical cable. When the optical transmission modules were applied to 152-channel SQUID magnetoencephalography system, this system maintained a field noise level of 3 fT/√Hz @ 100 Hz.

Bell-state generation on remote superconducting qubits with dark photons

Science.gov (United States)

Hua, Ming; Tao, Ming-Jie; Alsaedi, Ahmed; Hayat, Tasawar; Wei, Hai-Rui; Deng, Fu-Guo

2018-06-01

We present a scheme to generate the Bell state deterministically on remote transmon qubits coupled to different 1D superconducting resonators connected by a long superconducting transmission line. Using the coherent evolution of the entire system in the all-resonance regime, the transmission line need not to be populated with microwave photons which can robust against the long transmission line loss. This lets the scheme more applicable to the distributed quantum computing on superconducting quantum circuit. Besides, the influence from the small anharmonicity of the energy levels of the transmon qubits can be ignored safely.

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.

Superconducting power cables in Denmark - a case study

DEFF Research Database (Denmark)

Østergaard, Jacob

1997-01-01

A case study of a 450 MVA, 132 kV high temperature superconducting (HTS) power transmission cable has been carried out. In the study, a superconducting cable system is compared to a conventional cable system which is under construction for an actual transmission line in the Danish grid. The study...... that HTS cables will be less expensive for high power ratings, have lower losses for lines with a high load, and have a reduced reactive power production. The use of superconducting cables in Denmark accommodate plans by the Danish utility to make a substantial conversion of overhead lines to underground...

Superconducting coherence in a vortex line liquid

International Nuclear Information System (INIS)

Chen, T.; Teitel, S.

1995-01-01

We carry out simulations of the anisotropic uniformly frustrated 3d XY model, as a model for vortex line fluctuations in high T c superconductors. We compute the phase diagram as a function of temperature and anisotropy, for a fixed applied magnetic field B. We find two distinct phase transitions. Upon heating, there is first a lower T c perpendicular where the vortex line lattice melts and super-conducting coherence perpendicular to the applied magnetic field vanishes. At a higher T cz , within the vortex line liquid, superconducting coherence parallel to the applied magnetic field vanishes. For finite anisotropy, both T c perpendicular and T cz lie well below the crossover from the vortex line liquid to the normal state

Superconducting coaxial cable as a large capacity transmission medium for communication

International Nuclear Information System (INIS)

Mikoshiba, K.; Simohori, Y.; Ohmori, N.; Sone, F.

1974-01-01

In order to survey the feasibility of the superconducting communication system, the electrical performance of superconducting coaxial cable has been investigated experimentally. The results are as follows. The transmission loss can be described as a function of the frequency, a(f) = a 1 f 2 + a 2 f. Dielectric loss is dominant up to a few gigahertz. Improvement of the impedance irregularities due to dimensional imperfections along the cable smoothens the transmission loss versus frequency characteristics. The temperature dependence of the transmission loss agrees well with an approximate expression deduced using the Pippard temperature function. (author)

Quality factor of a transmission line coupled coplanar waveguide resonator

Energy Technology Data Exchange (ETDEWEB)

Besedin, Ilya [National University for Science and Technology (MISiS), Moscow (Russian Federation); National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow (Russian Federation); Menushenkov, Alexey P. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow (Russian Federation)

2018-12-15

We investigate analytically the coupling of a coplanar waveguide resonator to a coplanar waveguide feedline. Using a conformal mapping technique we obtain an expression for the characteristic mode impedances and coupling coefficients of an asymmetric multi-conductor transmission line. Leading order terms for the external quality factor and frequency shift are calculated. The obtained analytical results are relevant for designing circuit-QED quantum systems and frequency division multiplexing of superconducting bolometers, detectors and similar microwave-range multi-pixel devices. (orig.)

Cryogenic System for a High-Temperature Superconducting Power Transmission Cable

International Nuclear Information System (INIS)

Demko, J.A.; Gouge, M.J.; Hughey, R.L.; Lue, J.W.; Martin, R.; Sinha, U.; Stovall, J.P.

1999-01-01

High-temperature superconducting (HTS) cable systems for power transmission are under development that will use pressurized liquid nitrogen to provide cooling of the cable and termination hardware. Southwire Company and Oak Ridge National Laboratory have been operating a prototype HTS cable system that contains many of the typical components needed for a commercial power transmission application. It is being used to conduct research in the development of components and systems for eventual commercial deployment. The cryogenic system was built by Air Products and Chemicals, Allentown, Pennsylvania, and can circulate up to 0.35 kg/s of liquid nitrogen at temperatures as low as 67 K at pressures of 1 to 10 bars. Sufficient cooling is provided for testing a 5-m-long HTS transmission cable system that includes the terminations required for room temperature electrical connections. Testing of the 5-m HTS transmission cable has been conducted at the design ac conditions of 1250 A and 7.5 kV line to ground. This paper contains a description of the essential features of the HTS cable cryogenic system and performance results obtained during operation of the system. The salient features of the operation that are important in large commercial HTS cable applications will be discussed

Reprint of “Performance analysis of a model-sized superconducting DC transmission system based VSC-HVDC transmission technologies using RTDS”

International Nuclear Information System (INIS)

Dinh, Minh-Chau; Ju, Chang-Hyeon; Kim, Sung-Kyu; Kim, Jin-Geun; Park, Minwon; Yu, In-Keun

2013-01-01

Highlights: ► A model-sized superconducting VSC-HVDC system was designed and fabricated. ► A real-time simulation using Real Time Digital Simulator has been performed. ► The AC loss characteristics of HTS DC power cable caused by harmonics were analyzed. ► The AC loss of the HTS DC power cable will be used as a parameter to design the cable cooling system. -- Abstract: The combination of a high temperature superconducting DC power cable and a voltage source converter based HVDC (VSC-HVDC) creates a new option for transmitting power with multiple collection and distribution points for long distance and bulk power transmissions. It offers some greater advantages compared with HVAC or conventional HVDC transmission systems, and it is well suited for the grid integration of renewable energy sources in existing distribution or transmission systems. For this reason, a superconducting DC transmission system based HVDC transmission technologies is planned to be set up in the Jeju power system, Korea. Before applying this system to a real power system on Jeju Island, system analysis should be performed through a real time test. In this paper, a model-sized superconducting VSC-HVDC system, which consists of a small model-sized VSC-HVDC connected to a 2 m YBCO HTS DC model cable, is implemented. The authors have performed the real-time simulation method that incorporates the model-sized superconducting VSC-HVDC system into the simulated Jeju power system using Real Time Digital Simulator (RTDS). The performance analysis of the superconducting VSC-HVDC systems has been verified by the proposed test platform and the results were discussed in detail

Reprint of “Performance analysis of a model-sized superconducting DC transmission system based VSC-HVDC transmission technologies using RTDS”

Energy Technology Data Exchange (ETDEWEB)

Dinh, Minh-Chau, E-mail: thanchau7787@gmail.com [Changwon National University, 9 Sarim-Dong, Changwon 641-733 (Korea, Republic of); Ju, Chang-Hyeon; Kim, Sung-Kyu; Kim, Jin-Geun; Park, Minwon [Changwon National University, 9 Sarim-Dong, Changwon 641-733 (Korea, Republic of); Yu, In-Keun, E-mail: yuik@changwon.ac.kr [Changwon National University, 9 Sarim-Dong, Changwon 641-733 (Korea, Republic of)

2013-01-15

Highlights: ► A model-sized superconducting VSC-HVDC system was designed and fabricated. ► A real-time simulation using Real Time Digital Simulator has been performed. ► The AC loss characteristics of HTS DC power cable caused by harmonics were analyzed. ► The AC loss of the HTS DC power cable will be used as a parameter to design the cable cooling system. -- Abstract: The combination of a high temperature superconducting DC power cable and a voltage source converter based HVDC (VSC-HVDC) creates a new option for transmitting power with multiple collection and distribution points for long distance and bulk power transmissions. It offers some greater advantages compared with HVAC or conventional HVDC transmission systems, and it is well suited for the grid integration of renewable energy sources in existing distribution or transmission systems. For this reason, a superconducting DC transmission system based HVDC transmission technologies is planned to be set up in the Jeju power system, Korea. Before applying this system to a real power system on Jeju Island, system analysis should be performed through a real time test. In this paper, a model-sized superconducting VSC-HVDC system, which consists of a small model-sized VSC-HVDC connected to a 2 m YBCO HTS DC model cable, is implemented. The authors have performed the real-time simulation method that incorporates the model-sized superconducting VSC-HVDC system into the simulated Jeju power system using Real Time Digital Simulator (RTDS). The performance analysis of the superconducting VSC-HVDC systems has been verified by the proposed test platform and the results were discussed in detail.

Superconducting magnet system for the J-PARC neutrino beam line. Development, construction and operation of superconducting magnets

International Nuclear Information System (INIS)

Sasaki, Ken-ichi; Nakamoto, Tatsushi; Ajima, Yasuo; Okamura, Takahiro; Ogitsu, Toru; Kimura, Nobuhiro; Terashima, Akio; Tomaru, Takayuki; Higashi, Norio

2010-01-01

Superconducting combined-function magnets have been utilized for the 50-GeV, 750-kW proton beam line in the J-PARC neutrino experiment. The magnets are designed to provide a dipole field of 2.6 T combined with a quadrupole field of 19 T/m in a coil aperture of 173.4 mm at a nominal current of 7,345 A. Following the success of a prototype R and D project, a superconducting magnet system for the J-PARC neutrino beam line has been constructed since 2005. Using a new conceptual beam line with the superconducting combined-function magnets has demonstrated successful beam transport to the target neutrino production. (author)

High speed data transmission at the Superconducting Super Collider

International Nuclear Information System (INIS)

Leskovar, B.

1990-04-01

High speed data transmission using fiber optics in the data acquisition system of the Superconducting Super Collider has been investigated. Emphasis is placed on the high speed data transmission system overview, the local data network and on subassemblies, such as optical transmitters and receivers. Also, the performance of candidate subassemblies having a low power dissipation for the data acquisition system is discussed. 14 refs., 5 figs

Series Transmission Line Transformer

Science.gov (United States)

Buckles, Robert A.; Booth, Rex; Yen, Boris T.

2004-06-29

A series transmission line transformer is set forth which includes two or more of impedance matched sets of at least two transmissions lines such as shielded cables, connected in parallel at one end ans series at the other in a cascading fashion. The cables are wound about a magnetic core. The series transmission line transformer (STLT) which can provide for higher impedance ratios and bandwidths, which is scalable, and which is of simpler design and construction.

Parallel plate transmission line transformer

NARCIS (Netherlands)

Voeten, S.J.; Brussaard, G.J.H.; Pemen, A.J.M.

2011-01-01

A Transmission Line Transformer (TLT) can be used to transform high-voltage nanosecond pulses. These transformers rely on the fact that the length of the pulse is shorter than the transmission lines used. This allows connecting the transmission lines in parallel at the input and in series at the

Superconducting power transmission: the perils and promise

Energy Technology Data Exchange (ETDEWEB)

Forsyth, E B

1976-06-01

The development of bulk electricity transmission systems must be considered in the light of changing growth rates, increasing resistances to ehv overhead transmission and the tendency to concentrate generation in fewer sites. Helium-cooled or superconducting cables possess technical characteristics which will make them suitable as utility network components for power transmission over distances of ten to several hundred miles. These properties are illustrated by considering two applications in existing electrical networks. The first is a 43 mile system to transmit 4800 MVA and the second is a potential application under study in Pennsylvania to transmit 10,000 MVA over a distance of 350 miles or so. Helium-cooled versions of these transmission systems were designed to permit technical and economic evaluations. The major groups and institutions throughout the world engaged in the development of helium-cooled cables are listed and aspects of the technical approaches are briefly described.

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.

Atlas transmission line breakdown analysis

CERN Document Server

Nielsen, K E; Ballard, E O; Elizondo, J M; Gribble, R F; McCuistian, B T; Parsons, W M

1999-01-01

The Atlas facility will use 24 radially converging, vertically oriented and tapered, oil insulated, triplate transmission lines between the Marx generators and the central load region. Among the requirements of the transmission lines are low inductance and high reliability. The inter-conductor gap is nominally 2 cm and the lines taper from a height of 1.75 m at the Marx end to 0.32 m at the output end. The aluminum conductors, held together by 20 insulating spacers, are assembled and inserted as a unit into radial oil-filled steel tanks. The negative, high-voltage, center conductor is 2.54-cm thick and the outer ground conductors are 1.59-cm thick. All 24 triplate transmission lines connect to a transition section at near 1 m radius that couples the transmission lines to a disk/conical solid- dielectric-insulated power flow channel transmission line terminating at the load. Peak operating voltage on the lines can be as high as 240 kV with an effective stress time of 0.8 mu s. Testing of small sections of the ...

Technical and economic feasibility of superconducting power transmission: a case study

International Nuclear Information System (INIS)

Forsyth, E.B.; Mulligan, G.A.; Beck, J.W.; Williams, J.A.

1975-01-01

The long-range plans of the Long Island Lighting Company include the installation of 4600 MW of generation capacity at nuclear sites on eastern Long Island by the 1990's. A single site, Shoreham, was chosen for this study which would require transmission facilities to the Ruland Road substation, 43 miles away. Conventional 345 kV overhead and underground circuits are planned for this service. For the case study three superconducting cable schemes have been investigated which reflect various technical options. The superconducting cables have been designed to meet acceptable normal and contingency load flow conditions and to withstand maximum short circuit faults. A cost analysis has been made of the complete installation, providing a valuable comparison of the estimated cost of this new technology with conventional methods. The most favorable cost comparison is a two-circuit 345 kV superconducting system, which appears to be about one-half the cost of an all underground 345 kV high pressure oil-filled cable system. No reactive compensation will be required for the superconducting system, whereas extensive compensation is required for HPOF cables over the same distance. The cost estimate for the two-circuit superconducting system is about twice that of 345 kV overhead transmission, which would consist of two double circuits and one single circuit, assuming right-of-way could be obtained. (U.S.)

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.

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.

Transmission line capital costs

International Nuclear Information System (INIS)

Hughes, K.R.; Brown, D.R.

1995-05-01

The displacement or deferral of conventional AC transmission line installation is a key benefit associated with several technologies being developed with the support of the U.S. Department of Energy's Office of Energy Management (OEM). Previous benefits assessments conducted within OEM have been based on significantly different assumptions for the average cost per mile of AC transmission line. In response to this uncertainty, an investigation of transmission line capital cost data was initiated. The objective of this study was to develop a database for preparing preliminary estimates of transmission line costs. An extensive search of potential data sources identified databases maintained by the Bonneville Power Administration (BPA) and the Western Area Power Administration (WAPA) as superior sources of transmission line cost data. The BPA and WAPA data were adjusted to a common basis and combined together. The composite database covers voltage levels from 13.8 to 765 W, with cost estimates for a given voltage level varying depending on conductor size, tower material type, tower frame type, and number of circuits. Reported transmission line costs vary significantly, even for a given voltage level. This can usually be explained by variation in the design factors noted above and variation in environmental and land (right-of-way) costs, which are extremely site-specific. Cost estimates prepared from the composite database were compared to cost data collected by the Federal Energy Regulatory Commission (FERC) for investor-owned utilities from across the United States. The comparison was hampered because the only design specifications included with the FERC data were voltage level and line length. Working within this limitation, the FERC data were not found to differ significantly from the composite database. Therefore, the composite database was judged to be a reasonable proxy for estimating national average costs

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.

Quantum State Transmission in a Superconducting Charge Qubit-Atom Hybrid

Science.gov (United States)

Yu, Deshui; Valado, María Martínez; Hufnagel, Christoph; Kwek, Leong Chuan; Amico, Luigi; Dumke, Rainer

2016-01-01

Hybrids consisting of macroscopic superconducting circuits and microscopic components, such as atoms and spins, have the potential of transmitting an arbitrary state between different quantum species, leading to the prospective of high-speed operation and long-time storage of quantum information. Here we propose a novel hybrid structure, where a neutral-atom qubit directly interfaces with a superconducting charge qubit, to implement the qubit-state transmission. The highly-excited Rydberg atom located inside the gate capacitor strongly affects the behavior of Cooper pairs in the box while the atom in the ground state hardly interferes with the superconducting device. In addition, the DC Stark shift of the atomic states significantly depends on the charge-qubit states. By means of the standard spectroscopic techniques and sweeping the gate voltage bias, we show how to transfer an arbitrary quantum state from the superconducting device to the atom and vice versa. PMID:27922087

VT Digital Line Graph Miscellaneous Transmission Lines

Data.gov (United States)

Vermont Center for Geographic Information — (Link to Metadata) This datalayer is comprised of Miscellaineous Transmission Lines. Digital line graph (DLG) data are digital representations of cartographic...

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.

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)

Response analysis on nonuniform transmission line

Directory of Open Access Journals (Sweden)

Cvetković Zlata

2005-01-01

Full Text Available Transients on a loss less exponential transmission line with a pure resistance load are presented in this paper. The approach is based on the two-port presentation of the transmission line. Using Picard-Carson's method the transmission line equations are solved. The relationship between source voltage and the load voltage in s-domain is derived. All the results are plotted using program package Mathematica 3.0.

Power applications for superconducting cables in Denmark

DEFF Research Database (Denmark)

Tønnesen, Ole; Østergaard, Jacob; Olsen, S. Krüger

1999-01-01

In Denmark a growing concern for environmental protection has lead to wishes that the open country is kept free of overhead lines as far as possible. New lines under 100 kV and existing 60/50 kV lines should be established as underground cables. Superconducting cables represent an interesting...... in cases such as transmission of energy into cities and through areas of special interest. The planned large groups of windmills in Denmark generating up to 2000 MVA or more both on dry land and off-shore will be an obvious case for the application of superconducting AC or DC cables. These opportunities...... can be combined with other new technologies such as HVDC light transmission using isolated gate bipolar transistors (IGBTs). The network needed in a system with a substantial wind power generation has to be very strong in order to handle energy fluctuations. Such a network will be possible...

Conceptual design and development of a superconducting bus-line for the Large Helical Device

International Nuclear Information System (INIS)

Mito, T.; Takahata, K.; Yamada, S.; Yamamoto, J.; Uede, T.; Ikeda, M.

1993-01-01

A superconducting bus-line is proposed and preliminarily tested as an electrical feeder between the superconducting coils of the Large Helical Device (LHD) and their electrical power supply. The bus-line consists of a superconductor and its cryogenic transfer-line. The superconductor is a specially developed aluminum stabilized NbTi wire, which is installed in the innermost channel of the transfer-line. The vacuum insulated transfer-line consists of four corrugated tubes assembled coaxially. Liquid helium flows through the innermost channel and shield gas flows through another annular channel in the line. We are completing the conceptual design of the bus-line and the installation plan for the LHD experimental hall and are carrying out development of wires, including an investigation of their mechanical properties and electrical insulation. This report describes the conceptual design of the superconducting bus-line for the LHD, and the results we obtained recently during the design and development of a full-scale demonstration facility. (orig.)

Transmission of radioiodine through sampling lines

International Nuclear Information System (INIS)

Unrein, P.J.; Pelletier, C.A.; Cline, J.E.; Voilleque, P.G.

1985-01-01

An experimental program to measure radioiodine transmission through sampling lines is described. The transmission depends upon both deposition on and resuspension from the walls of the line. The deposition and resuspension processes are themselves controlled by the length, diameter, and material of the line and the conditions under which it is operated. The operating conditions under study are sampling flow rate, temperature and relative humidity. Measurement results have been interpreted in terms of a four-compartment model of radioiodine deposition and resuspension. The model is applied to each of twenty or more segments of the line. Experimental measurements of short-term transmission fractions and the deposition velocities derived from them are presented for six lines. Data on resuspension rates for the same lines were obtained and are also discussed

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.

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.

Beam transfer lines for the Tandem-superconducting cyclotron at Lab. Nazionale del Sud

International Nuclear Information System (INIS)

Calabretta, L.; Cuttone, G.; DiBernardo, P.; Giove, D.; Raia, G.; Yan, C.; Cao, L.; Liu, K.

1988-01-01

At the L.N.S. an MP-Tandem will be used as injector for the Superconducting Cyclotron. This paper describes the handling beam system for the Superconducting Cyclotron. All the lines are designed to be achromatic. Home made beam profile monitor is the main diagnostic device and its design and preliminary tests are presented. The distributed computer control for all the beam lines and bunching system is described too. The status of beam transfer line from tandem to S.C. and of bunching system is presented

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)

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.

Rf superconducting devices

International Nuclear Information System (INIS)

Hartwig, W.H.; Passow, C.

1975-01-01

Topics discussed include (1) the theory of superconductors in high-frequency fields (London surface impedance, anomalous normal surface resistance, pippard nonlocal theory, quantum mechanical model, superconductor parameters, quantum mechanical calculation techniques for the surface, impedance, and experimental verification of surface impedance theories); (2) residual resistance (separation of losses, magnetic field effects, surface resistance of imperfect and impure conductors, residual loss due to acoustic coupling, losses from nonideal surfaces, high magnetic field losses, field emission, and nonlinear effects); (3) design and performance of superconducting devices (design considerations, materials and fabrication techniques, measurement of performance, and frequency stability); (4) devices for particle acceleration and deflection (advantages and problems of using superconductors, accelerators for fast particles, accelerators for particles with slow velocities, beam optical devices separators, and applications and projects under way); (5) applications of low-power superconducting resonators (superconducting filters and tuners, oscillators and detectors, mixers and amplifiers, antennas and output tanks, superconducting resonators for materials research, and radiation detection with loaded superconducting resonators); and (6) transmission and delay lines

Power charging and discharging characteristics of smes connected to artificial transmission line

International Nuclear Information System (INIS)

Nitta, T.; Okada, T.; Shirai, Y.

1985-01-01

To consider the characteristics of SMES and to investigate problems on the operations of SMES in power systems, we carried out some experiments on an experimental network. In the network, a small superconducting magnet is connected to a small synchronous generator through a double thyristorized converter and transformers. The generator is connected to the regional power system through artifitial transmission lines, AC power into or out of SMES and reactive power are controlled. Furthermore, a computer simulation program is made for the experimental system. The results of the simulation are compared with those of the experiments. For the experiments and the simulation, the harmonics current-flow, power-flow, characteristics of the generator and so on, are discussed

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

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

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.

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...

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

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...

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...

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...

University's role in research on superconducting power transmission

International Nuclear Information System (INIS)

Forsyth, E.B.

1974-01-01

Power transmission by superconducting cables appears to have enormous potential for the utility industry. It has still to be demonstrated that it will become a viable and economically competitive technology, however, development aimed at this goal by major research establishments has already exposed numerous research problems suitable for investigation by well qualified university departments without requiring large expenditures for equipment. What is missing in an organizational structure to relate work to the primary goals, monitor progress and influence the funding decisions of the major agencies. This does not seem difficult to set up, but continued success will require a long-term commitment from the participants

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).

Microwave dynamics of high aspect ratio superconducting nanowires studied using self-resonance

Science.gov (United States)

Santavicca, Daniel F.; Adams, Jesse K.; Grant, Lierd E.; McCaughan, Adam N.; Berggren, Karl K.

2016-06-01

We study the microwave impedance of extremely high aspect ratio (length/width ≈ 5000) superconducting niobium nitride nanowires. The nanowires are fabricated in a compact meander geometry that is in series with the center conductor of a 50 Ω coplanar waveguide transmission line. The transmission coefficient of the sample is measured up to 20 GHz. At high frequency, a peak in the transmission coefficient is seen. Numerical simulations show that this is a half-wave resonance along the length of the nanowire, where the nanowire acts as a high impedance, slow wave transmission line. This resonance sets the upper frequency limit for these nanowires as inductive elements. Fitting simulations to the measured resonance enables a precise determination of the nanowire's complex sheet impedance at the resonance frequency. The real part is a measure of dissipation, while the imaginary part is dominated by kinetic inductance. We characterize the dependence of the sheet resistance and sheet inductance on both temperature and current and compare the results to recent theoretical predictions for disordered superconductors. These results can aid in the understanding of high frequency devices based on superconducting nanowires. They may also lead to the development of novel superconducting devices such as ultra-compact resonators and slow-wave structures.

49 CFR 192.719 - Transmission lines: Testing of repairs.

Science.gov (United States)

2010-10-01

... pipe before it is installed. (b) Testing of repairs made by welding. Each repair made by welding in... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Testing of repairs. 192.719... Transmission lines: Testing of repairs. (a) Testing of replacement pipe. If a segment of transmission line is...

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.

Circuit QED with hybrid metamaterial transmission lines

Energy Technology Data Exchange (ETDEWEB)

Ruloff, Stefan; Taketani, Bruno; Wilhelm, Frank [Theoretical Physics, Universitaet des Saarlandes, Saarbruecken (Germany)

2016-07-01

We're working on the theory of metamaterials providing some interesting results. The negative refraction index causes an opposite orientation of the wave vector k and the Poynting vector S of the travelling waves. Hence the metamaterial has a falling dispersion relation ∂ω(k)/∂k < 0 implying that low frequencies correspond to short wavelengths. Metamaterials are simulated by left-handed transmission lines consisting of discrete arrays of series capacitors and parallel inductors to ground. Unusual physics arises when right-and left-handed transmission lines are coupled forming a hybrid metamaterial transmission line. E.g. if a qubit is placed in front of a hybrid metamaterial transmission line terminated in an open circuit, the spontaneous emission rate is weakened or unaffected depending on the transition frequency of the qubit. Some other research interests are the general analysis of metamaterial cavities and the mode structure of hybrid metamaterial cavities for QND readout of multi-qubit operators. Especially the precise answer to the question about the definition of the mode volume of a metamaterial cavity is one of our primary goals.

Demonstration of superconducting micromachined cavities

Energy Technology Data Exchange (ETDEWEB)

Brecht, T., E-mail: teresa.brecht@yale.edu; Reagor, M.; Chu, Y.; Pfaff, W.; Wang, C.; Frunzio, L.; Devoret, M. H.; Schoelkopf, R. J. [Department of Applied Physics, Yale University, New Haven, Connecticut 06511 (United States)

2015-11-09

Superconducting enclosures will be key components of scalable quantum computing devices based on circuit quantum electrodynamics. Within a densely integrated device, they can protect qubits from noise and serve as quantum memory units. Whether constructed by machining bulk pieces of metal or microfabricating wafers, 3D enclosures are typically assembled from two or more parts. The resulting seams potentially dissipate crossing currents and limit performance. In this letter, we present measured quality factors of superconducting cavity resonators of several materials, dimensions, and seam locations. We observe that superconducting indium can be a low-loss RF conductor and form low-loss seams. Leveraging this, we create a superconducting micromachined resonator with indium that has a quality factor of two million, despite a greatly reduced mode volume. Inter-layer coupling to this type of resonator is achieved by an aperture located under a planar transmission line. The described techniques demonstrate a proof-of-principle for multilayer microwave integrated quantum circuits for scalable quantum computing.

State Estimation-based Transmission line parameter identification

Directory of Open Access Journals (Sweden)

Fredy Andrés Olarte Dussán

2010-01-01

Full Text Available This article presents two state-estimation-based algorithms for identifying transmission line parameters. The identification technique used simultaneous state-parameter estimation on an artificial power system composed of several copies of the same transmission line, using measurements at different points in time. The first algorithm used active and reactive power measurements at both ends of the line. The second method used synchronised phasor voltage and current measurements at both ends. The algorithms were tested in simulated conditions on the 30-node IEEE test system. All line parameters for this system were estimated with errors below 1%.

High voltage transmission lines - what are the hazards

International Nuclear Information System (INIS)

Repacholi, M.H.

1985-01-01

With the increasing use of high voltage alternating current (HVAC) transmission lines there is a growing concern among the public about possible human health effects resulting from exposure to the electric fields associated with these lines. While there is no definitive evidence of such effects, mounting public fear and activism over hypothesized health risks is already causing delays in the licensing and constuction of major power transmission facilities, and is encouraging the formation of regulatory policy. This paper briefly reviews the concerns, biological effects data and standards for HVAC transmission lines

Scheme for realizing quantum computation and quantum information transfer with superconducting qubits coupling to a 1D transmission line resonator

International Nuclear Information System (INIS)

Zhen-Gang, Shi; Xiong-Wen, Chen; Xi-Xiang, Zhu; Ke-Hui, Song

2009-01-01

This paper proposes a simple scheme for realizing one-qubit and two-qubit quantum gates as well as multiqubit entanglement based on dc-SQUID charge qubits through the control of their coupling to a 1D transmission line resonator (TLR). The TLR behaves effectively as a quantum data-bus mode of a harmonic oscillator, which has several practical advantages including strong coupling strength, reproducibility, immunity to 1/f noise, and suppressed spontaneous emission. In this protocol, the data-bus does not need to stay adiabatically in its ground state, which results in not only fast quantum operation, but also high-fidelity quantum information processing. Also, it elaborates the transfer process with the 1D transmission line. (general)

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.

Ground-based transmission line conductor motion sensor

International Nuclear Information System (INIS)

Jacobs, M.L.; Milano, U.

1988-01-01

A ground-based-conductor motion-sensing apparatus is provided for remotely sensing movement of electric-power transmission lines, particularly as would occur during the wind-induced condition known as galloping. The apparatus is comprised of a motion sensor and signal-generating means which are placed underneath a transmission line and will sense changes in the electric field around the line due to excessive line motion. The detector then signals a remote station when a conditioning of galloping is sensed. The apparatus of the present invention is advantageous over the line-mounted sensors of the prior art in that it is easier and less hazardous to install. The system can also be modified so that a signal will only be given when particular conditions, such as specific temperature range, large-amplitude line motion, or excessive duration of the line motion, are occurring

COMMERCIALIZATION DEMONSTRATION OF MID-SIZED SUPERCONDUCTING MAGNETIC ENERGY STORAGE TECHNOLOGY FOR ELECTRIC UTILITYAPPLICATIONS

Energy Technology Data Exchange (ETDEWEB)

CHARLES M. WEBER

2008-06-24

As an outgrowth of the Technology Reinvestment Program of the 1990’s, an Agreement was formed between BWXT and the DOE to promote the commercialization of Superconducting Magnetic Energy Storage (SMES) technology. Business and marketing studies showed that the performance of electric transmission lines could be improved with this SMES technology by stabilizing the line thereby allowing the reserved stability margin to be used. One main benefit sought was to double the capacity and the amount of energy flow on an existing transmission line by enabling the use of the reserved stability margin, thereby doubling revenue. Also, electrical disturbances, power swings, oscillations, cascading disturbances and brown/black-outs could be mitigated and rendered innocuous; thereby improving power quality and reliability. Additionally, construction of new transmission lines needed for increased capacity could be delayed or perhaps avoided (with significant savings) by enabling the use of the reserved stability margin of the existing lines. Two crucial technical aspects were required; first, a large, powerful, dynamic, economic and reliable superconducting magnet, capable of oscillating power flow was needed; and second, an electrical power interface and control to a transmission line for testing, demonstrating and verifying the benefits and features of the SMES system was needed. A project was formed with the goals of commercializing the technology by demonstrating SMES technology for utility applications and to establish a domestic capability for manufacturing large superconducting magnets for both commercial and defense applications. The magnet had very low AC losses to support the dynamic and oscillating nature of the stabilizing power flow. Moreover, to economically interface to the transmission line, the magnet had the largest operating voltage ever made. The manufacturing of that design was achieved by establishing a factory with newly designed and acquired equipment

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....

Electromagnetic analysis using transmission line variables

CERN Document Server

Weiner, Maurice

2010-01-01

This book employs a relatively new method for solving electromagnetic problems, one which makes use of a transmission line matrix (TLM). The propagation space is imagined to be filled with this matrix. The propagating fields and physical properties are then mapped onto the matrix. Mathematically, the procedures are identical with the traditional numerical methods; however, the interpretation and physical appeal of the transmission line matrix are far superior. Any change in the matrix has an immediate physical significance. What is also very important is that the matrix becomes a launching pad

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

Measurements of a crenelated iron pole tip for the VLHC transmission line magnet

CERN Document Server

Di Marco, J; Kashikhin, V V; Makarov, A A; Schlabach, P; MacKay, W W

1999-01-01

The Very Large Hadron Collider (VLHC) is under conceptual design in Fermilab. One option under development is a 2-Tesla warm iron 2-in-1 single turn superferric magnet built around an 80 kA superconducting transmission line. A normal-conducting test stand was built to optimize the iron lamination shape for this magnet. It uses a water- cooled copper winding to provide the 100 kA-turns needed to generate 2 Tesla fields in both 20 mm air gaps of the magnet. A magnetic measurement facility has been set up for magnetic field mapping, which includes a flat measurement coil, precision stage for coil motion and integrator. Results from a first test of the "crenelation" technique to mitigate the saturation sextupole in iron magnets are described and future plans are discussed. (5 refs).

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.

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.

High-temperature superconducting conductors and cables

International Nuclear Information System (INIS)

Peterson, D.E.; Maley, M.P.; Boulaevskii, L.; Willis, J.O.; Coulter, J.Y.; Ullmann, J.L.; Cho, Jin; Fleshler, S.

1996-01-01

This is the final report of a 3-year LDRD project at LANL. High-temperature superconductivity (HTS) promises more efficient and powerful electrical devices such as motors, generators, and power transmission cables; however this depends on developing HTS conductors that sustain high current densities J c in high magnetic fields at temperatures near liq. N2's bp. Our early work concentrated on Cu oxides but at present, long wire and tape conductors can be best made from BSCCO compounds with high J c at low temperatures, but which are degraded severely at temperatures of interest. This problem is associated with thermally activated motion of magnetic flux lines in BSCCO. Reducing these dc losses at higher temperatures will require a high density of microscopic defects that will pin flux lines and inhibit their motion. Recently it was shown that optimum defects can be produced by small tracks formed by passage of energetic heavy ions. Such defects result when Bi is bombarded with high energy protons. The longer range of protons in matter suggests the possibility of application to tape conductors. AC losses are a major limitation in many applications of superconductivity such as power transmission. The improved pinning of flux lines reduces ac losses, but optimization also involves other factors. Measuring and characterizing these losses with respect to material parameters and conductor design is essential to successful development of ac devices

Insulation systems for superconducting transmission cables

DEFF Research Database (Denmark)

Tønnesen, Ole

1996-01-01

the electrical insulation is placed outside both the superconducting tube and the cryostat. The superconducting tube is cooled by liquid nitrogen which is pumped through the hollow part of the tube.2) The cryogenic dielectric design, where the electrical insulation is placed inside the cryostat and thus is kept...

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...

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

Risk Analysis Method Based on FMEA for Transmission Line in Lightning Hazards

Directory of Open Access Journals (Sweden)

You-Yuan WANG

2014-05-01

Full Text Available Failure rate of transmission line and reliability of power system are significantly affected by Lightning meteorological factor. In view of the complexity and variability of Lightning meteorological factors, this paper presents lightning trip-out rate model of transmission line in considering distribution of ground flash density and lightning day hours. Meanwhile, presents a failure rate model of transmission line in different condition, and a risk analysis method for transmission line considering multiple risk factors based on risk quantification. This method takes Lightning meteorological factor as the main evaluation standard, and establishes risk degree evaluation system for transmission line including another five evaluation standard. Put forward the risk indicators by quantify the risk factors based on experience date of transmission line in service. Based on the risk indexes comprehensive evaluation is conducted, and the evaluation result closer to practice is achieved, providing basis for transmission line risk warning and maintenance strategy. Through the risk analysis for 220 kV transmission line in a certain power supply bureau, the effectiveness of the proposed method is validated.

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

Fermion-fermion scattering in quantum field theory with superconducting circuits.

Science.gov (United States)

García-Álvarez, L; Casanova, J; Mezzacapo, A; Egusquiza, I L; Lamata, L; Romero, G; Solano, E

2015-02-20

We propose an analog-digital quantum simulation of fermion-fermion scattering mediated by a continuum of bosonic modes within a circuit quantum electrodynamics scenario. This quantum technology naturally provides strong coupling of superconducting qubits with a continuum of electromagnetic modes in an open transmission line. In this way, we propose qubits to efficiently simulate fermionic modes via digital techniques, while we consider the continuum complexity of an open transmission line to simulate the continuum complexity of bosonic modes in quantum field theories. Therefore, we believe that the complexity-simulating-complexity concept should become a leading paradigm in any effort towards scalable quantum simulations.

Design of Chebychev’s Low Pass Filters Using Nonuniform Transmission Lines

Directory of Open Access Journals (Sweden)

Said Attamimi

2016-03-01

Full Text Available Transmission lines are utilized in many applications to convey energy as well as information. Nonuniform transmission lines (NTLs are obtained through variation of the characteristic quantities along the axial direction. Such NTLs can be used to design network elements, like matching circuits, delay equalizers, filters, VLSI interconnections, etc. In this work, NTLs were analyzed with a numerical method based on the implementation of method of moment. In order to approximate the voltage and current distribution along the transmission line, a sum of basis functions with unknown amplitudes was introduced. As basis function, a constant function was used. In this work, we observed several cases such as lossless and lossy uniform transmission lines with matching and arbitrary load. These cases verified the algorithm developed in this work. The second example consists of nonuniform transmission lines in the form of abruptly changing transmission lines. This structure was used to design a Chebychev’s low pass filter. The calculated reflection and transmission factors of the filters showed some coincidences with the measurements.

A superconducting shield to protect astronauts

CERN Document Server

Antonella Del Rosso

2015-01-01

The CERN Superconductors team in the Technology department is involved in the European Space Radiation Superconducting Shield (SR2S) project, which aims to demonstrate the feasibility of using superconducting magnetic shielding technology to protect astronauts from cosmic radiation in the space environment. The material that will be used in the superconductor coils on which the project is working is magnesium diboride (MgB2), the same type of conductor developed in the form of wire for CERN for the LHC High Luminosity Cold Powering project.   Image: K. Anthony/CERN. Back in April 2014, the CERN Superconductors team announced a world-record current in an electrical transmission line using cables made of the MgB2 superconductor. This result proved that the technology could be used in the form of wire and could be a viable solution for both electrical transmission for accelerator technology and long-distance power transportation. Now, the MgB2 superconductor has found another application: it wi...

Parallel superconducting strip-line detectors: reset behaviour in the single-strip switch regime

International Nuclear Information System (INIS)

Casaburi, A; Heath, R M; Tanner, M G; Hadfield, R H; Cristiano, R; Ejrnaes, M; Nappi, C

2014-01-01

Superconducting strip-line detectors (SSLDs) are an important emerging technology for the detection of single molecules in time-of-flight mass spectrometry (TOF-MS). We present an experimental investigation of a SSLD laid out in a parallel configuration, designed to address selected single strip-lines operating in the single-strip switch regime. Fast laser pulses were tightly focused onto the device, allowing controllable nucleation of a resistive region at a specific location and study of the subsequent device response dynamics. We observed that in this regime, although the strip-line returns to the superconducting state after triggering, no effective recovery of the bias current occurs, in qualitative agreement with a phenomenological circuit simulation that we performed. Moreover, from theoretical considerations and by looking at the experimental pulse amplitude distribution histogram, we have the first confirmation of the fact that the phenomenological London model governs the current redistribution in these large area devices also after detection events. (paper)

High voltage superconducting switch for power application

International Nuclear Information System (INIS)

Mawardi, O.; Ferendeci, A.; Gattozzi, A.

1983-01-01

This paper reports the development of a novel interrupter which meets the requirements of a high voltage direct current (HVDC) power switch and at the same time doubles as a current limiter. The basic concept of the interrupter makes use of a fast superconducting, high capacity (SHIC) switch that carries the full load current while in the superconducting state and reverts to the normal resistive state when triggered. Typical design parameters are examined for the case of a HVDC transmission line handling 2.5KA at 150KVDC. The result is a power switch with superior performance and smaller size than the ones reported to date

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.

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).

Computation of nonuniform transmission lines using the FDTD method

Energy Technology Data Exchange (ETDEWEB)

Miranda, G.C.; Paulino, J.O.S. [Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil). School of Engineering

1997-12-31

Calculation of lightning overvoltages on transmission lines has been described. Lightning induced overvoltages are of great significance under certain conditions because of the main characteristics of the phenomena. The lightning channel model is one of the most important parameters essential to obtaining the generated electromagnetic fields. In this study, nonuniform transmission line equations were solved using the finite difference method and the leap-frog scheme, the Finite Difference Time Domain (FDTD) method. The subroutine was interfaced with the Electromagnetic Transients Program (EMTP). Two models were used to represent the characteristic impedance of the nonuniform lines used to model the transmission line towers and the lightning main channel. The advantages of the FDTD method was the much smaller code and faster processing time. 35 refs., 5 figs.

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

Superconducting Magnetic Energy Storage (SMES). (Latest citations from the NTIS bibliographic database). Published Search

International Nuclear Information System (INIS)

1993-11-01

The bibliography contains citations concerning the technology and use of superconducting magnetic energy storage (SMES). The design, analysis, evaluation, and operation of SMES systems and equipment are discussed. Topics include utility scale SMES plants, SMES for transmission line stabilization, design and protection of superconducting magnets and coils, computer controlled SMES systems, and fusion power reactors. (Contains a minimum of 82 citations and includes a subject term index and title list.)

Superconducting Magnetic Energy Storage (SMES). (Latest citations from the NTIS bibliographic database). Published Search

International Nuclear Information System (INIS)

1993-09-01

The bibliography contains citations concerning the technology and use of superconducting magnetic energy storage (SMES). The design, analysis, evaluation, and operation of SMES systems and equipment are discussed. Topics include utility scale SMES plants, SMES for transmission line stabilization, design and protection of superconducting magnets and coils, computer controlled SMES systems, and fusion power reactors. (Contains a minimum of 82 citations and includes a subject term index and title list.)

Quantum Devices Bonded Beneath a Superconducting Shield: Part 2

Science.gov (United States)

McRae, Corey Rae; Abdallah, Adel; Bejanin, Jeremy; Earnest, Carolyn; McConkey, Thomas; Pagel, Zachary; Mariantoni, Matteo

The next-generation quantum computer will rely on physical quantum bits (qubits) organized into arrays to form error-robust logical qubits. In the superconducting quantum circuit implementation, this architecture will require the use of larger and larger chip sizes. In order for on-chip superconducting quantum computers to be scalable, various issues found in large chips must be addressed, including the suppression of box modes (due to the sample holder) and the suppression of slot modes (due to fractured ground planes). By bonding a metallized shield layer over a superconducting circuit using thin-film indium as a bonding agent, we have demonstrated proof of concept of an extensible circuit architecture that holds the key to the suppression of spurious modes. Microwave characterization of shielded transmission lines and measurement of superconducting resonators were compared to identical unshielded devices. The elimination of box modes was investigated, as well as bond characteristics including bond homogeneity and the presence of a superconducting connection.

The LHCb VELO analogue transmission line

International Nuclear Information System (INIS)

Bay, A.; Borel, J.; Buytaert, J.; De Laere, S.; Frei, R.; Haefeli, G.; Koppenburg, P.; Locatelli, L.; Schneider, O.; Zehr, F.

2010-01-01

The Vertex Locator is one of the most important sub-detectors of the LHCb experiment, which is devoted to B physics. The signals from the silicon strip sensors are multiplexed at 40 MHz and transported by 60 m copper lines to the counting stations placed in a radiation safe area. This paper describes the development of this long transmission line and its performance.

Controllable quantum information network with a superconducting system

International Nuclear Information System (INIS)

Zhang, Feng-yang; Liu, Bao; Chen, Zi-hong; Wu, Song-lin; Song, He-shan

2014-01-01

We propose a controllable and scalable architecture for quantum information processing using a superconducting system network, which is composed of current-biased Josephson junctions (CBJJs) as tunable couplers between the two superconducting transmission line resonators (TLRs), each coupling to multiple superconducting qubits (SQs). We explicitly demonstrate that the entangled state, the phase gate, and the information transfer between any two selected SQs can be implemented, respectively. Lastly, numerical simulation shows that our scheme is robust against the decoherence of the system. -- Highlights: •An architecture for quantum information processing is proposed. •The quantum information transfer between any two selected SQs is implemented. •This proposal is robust against the decoherence of the system. •This architecture can be fabricated on a chip down to the micrometer scale

Design of the Yang magnetically-insulated transmission line

International Nuclear Information System (INIS)

Gu Yuanchao; Song Shenyi

2002-01-01

The authors have designed a new magnetically insulated transmission line (MITL) for the Yang accelerator. The differences between the existing line and the designing one are given. The electric strength of some special regions on the lines and the inductance of the lines have been calculated. The authors have checked the states of magnetic insulation on the designing line

Composite Based EHV AC Overhead Transmission Lines

DEFF Research Database (Denmark)

Sørensen, Thomas Kjærsgaard

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...

Superconductivity

CERN Document Server

Thomas, D B

1974-01-01

A short general review is presented of the progress made in applied superconductivity as a result of work performed in connection with the high-energy physics program in Europe. The phenomenon of superconductivity and properties of superconductors of Types I and II are outlined. The main body of the paper deals with the development of niobium-titanium superconducting magnets and of radio-frequency superconducting cavities and accelerating structures. Examples of applications in and for high-energy physics experiments are given, including the large superconducting magnet for the Big European Bubble Chamber, prototype synchrotron magnets for the Super Proton Synchrotron, superconducting d.c. beam line magnets, and superconducting RF cavities for use in various laboratories. (0 refs).

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...

Exploring the physics of superconducting qubits strongly coupled to microwave frequency photons

Energy Technology Data Exchange (ETDEWEB)

Wallraff, Andreas [ETH Zurich (Switzerland)

2013-07-01

Using modern micro and nano-fabrication techniques combined with superconducting materials we realize electronic circuits the properties of which are governed by the laws of quantum mechanics. In such circuits the strong interaction of photons with superconducting quantum two-level systems allows us to probe fundamental quantum properties of light and to develop components for applications in quantum information technology. Here, I present experiments in which we have created and probed entanglement between stationary qubits and microwave photons freely propagating down a transmission line. In these experiments we use superconducting parametric amplifiers realized in our lab to detect both qubit and photon states efficiently. Using similar techniques we aim at demonstrating a deterministic scheme for teleportation of quantum states in a macroscopic system based on superconducting circuits.

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

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

EC Transmission Line Risk Identification and Analysis

Energy Technology Data Exchange (ETDEWEB)

Bigelow, Tim S [ORNL

2012-04-01

The purpose of this document is to assist in evaluating and planning for the cost, schedule, and technical project risks associated with the delivery and operation of the EC (Electron cyclotron) transmission line system. In general, the major risks that are anticipated to be encountered during the project delivery phase associated with the implementation of the Procurement Arrangement for the EC transmission line system are associated with: (1) Undefined or changing requirements (e.g., functional or regulatory requirements) (2) Underperformance of prototype, first unit, or production components during testing (3) Unavailability of qualified vendors for critical components Technical risks associated with the design and operation of the system are also identified.

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 capaci...... 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....

Quantum heat engine with coupled superconducting resonators

DEFF Research Database (Denmark)

Hardal, Ali Ümit Cemal; Aslan, Nur; Wilson, C. M.

2017-01-01

We propose a quantum heat engine composed of two superconducting transmission line resonators interacting with each other via an optomechanical-like coupling. One resonator is periodically excited by a thermal pump. The incoherently driven resonator induces coherent oscillations in the other one...... the signatures of quantum behavior in the statistical and thermodynamic properties of the system. We find evidence of a quantum enhancement in the power output of the engine at low temperatures....

Superconducting bandpass delta-sigma modulator

International Nuclear Information System (INIS)

Bulzacchelli, J.F.; Lee, H.-S.; Misewich, J.A.; Ketchen, M.B.

1999-01-01

Bandpass delta-sigma modulators digitize narrowband signals with high dynamic range and linearity. The required sampling rate is only a few times higher than the centre frequency of the input. This paper presents a superconducting bandpass delta-sigma modulator for direct analogue-to-digital conversion of RF signals in the GHz range. The input signal is capacitively coupled to one end of a microstrip transmission line, and a single flux quantum balanced comparator quantizes the current flowing out of the other end. Quantization noise is suppressed at the quarter-wave resonance of the transmission line (about 2 GHz in our design). Circuit performance at a 20 GHz sampling rate has been studied with several long JSIM simulations. Full-scale (FS) input sensitivity is 20 mV (rms), and in-band noise is -53 dBFS and -57 dBFS over bandwidths of 39 MHz and 19.5 MHz, respectively. In-band intermodulation distortion is better than -69 dBFS. (author)

Reconfigurable Wave Velocity Transmission Lines for Phased Arrays

Science.gov (United States)

Host, Nick; Chen, Chi-Chih; Volakis, John L.; Miranda, Felix

2013-01-01

Phased array antennas showcase many advantages over mechanically steered systems. However, they are also more complex, heavy and most importantly costly. This presentation paper presents a concept which overcomes these detrimental attributes by eliminating all of the phase array backend (including phase shifters). Instead, a wave velocity reconfigurable transmission line is used in a series fed array arrangement to allow phase shifting with one small (100mil) mechanical motion. Different configurations of the reconfigurable wave velocity transmission line are discussed and simulated and experimental results are presented.

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....

Upgrading transmission lines with aerial LiDAR technology

Energy Technology Data Exchange (ETDEWEB)

Koop, J.E. [Manitoba Hydro, Winnipeg, MB (Canada)

2003-04-01

LiDAR (Light Detection and Ranging) technology is described as an example of techniques used by hydro companies to increase their capacity with existing plants, and within tight budget constraints. LiDAR was chosen by Manitoba Hydro primarily because LiDAR's data collection method offers very fast turn-around time from collection to delivery, and most importantly because of LiDAR's highly accurate ability to map terrain and wire catenary shape in every span. The article describes a case study of the 'Nip and Tuck' method of wire re-tensioning based on LiDAR data, which was used by Manitoba Hydro to create a computer model of Saskatchewan Hydro's transmission line capacity on its 138 kV transmission line between Saskatoon and North Battleford. The model was needed to analyze the existing line conditions in an effort to minimize cascading failures on the 40-year old line. Using the 'Nip and Tuck' technology in combination with LiDAR, SaskPower engineers were able to complete the required modifications to raise transmission wire operating temperatures on the 135 km long line to 66 degree C in only 36 days, and at a cost that was 80 per cent less than the cost would have been using conventional techniques ($232,000 instead of the estimated $1.25 million).

The creation of high-temperature superconducting cables of megawatt range in Russia

Science.gov (United States)

Sytnikov, V. E.; Bemert, S. E.; Krivetsky, I. V.; Romashov, M. A.; Popov, D. A.; Fedotov, E. V.; Komandenko, O. V.

2015-12-01

Urgent problems of the power industry in the 21st century require the creation of smart energy systems, providing a high effectiveness of generation, transmission, and consumption of electric power. Simultaneously, the requirements for controllability of power systems and ecological and resource-saving characteristics at all stages of production and distribution of electric power are increased. One of the decision methods of many problems of the power industry is the development of new high-efficiency electrical equipment for smart power systems based on superconducting technologies to ensure a qualitatively new level of functioning of the electric power industry. The intensive research and development of new types of electrical devices based on superconductors are being carried out in many industrialized advanced countries. Interest in such developments has especially increased in recent years owing to the discovery of so-called high-temperature superconductors (HTS) that do not require complicated and expensive cooling devices. Such devices can operate at cooling by inexpensive and easily accessible liquid nitrogen. Taking into account the obvious advantages of superconducting cable lines for the transmission of large power flows through an electrical network, as compared with conventional cables, the Federal Grid Company of Unified Energy System (JSC FGC UES) initiated a research and development program including the creation of superconducting HTS AC and DC cable lines. Two cable lines for the transmitted power of 50 MVA/MW at 20 kV were manufactured and tested within the framework of the program.

The creation of high-temperature superconducting cables of megawatt range in Russia

Energy Technology Data Exchange (ETDEWEB)

Sytnikov, V. E., E-mail: vsytnikov@gmail.com; Bemert, S. E.; Krivetsky, I. V.; Romashov, M. A. [JSC NTTs FSC EES (Russian Federation); Popov, D. A.; Fedotov, E. V.; Komandenko, O. V. [JSC Irkutskkabel (Russian Federation)

2015-12-15

Urgent problems of the power industry in the 21st century require the creation of smart energy systems, providing a high effectiveness of generation, transmission, and consumption of electric power. Simultaneously, the requirements for controllability of power systems and ecological and resource-saving characteristics at all stages of production and distribution of electric power are increased. One of the decision methods of many problems of the power industry is the development of new high-efficiency electrical equipment for smart power systems based on superconducting technologies to ensure a qualitatively new level of functioning of the electric power industry. The intensive research and development of new types of electrical devices based on superconductors are being carried out in many industrialized advanced countries. Interest in such developments has especially increased in recent years owing to the discovery of so-called high-temperature superconductors (HTS) that do not require complicated and expensive cooling devices. Such devices can operate at cooling by inexpensive and easily accessible liquid nitrogen. Taking into account the obvious advantages of superconducting cable lines for the transmission of large power flows through an electrical network, as compared with conventional cables, the Federal Grid Company of Unified Energy System (JSC FGC UES) initiated a research and development program including the creation of superconducting HTS AC and DC cable lines. Two cable lines for the transmitted power of 50 MVA/MW at 20 kV were manufactured and tested within the framework of the program.

Advanced high-speed protection for transmission lines with different configurations

Energy Technology Data Exchange (ETDEWEB)

Tholomier, D.; Naisani, P. [Areva T and D Automation Canada Inc., Monteal, PQ (Canada); Apostolov, A. [Omicron Electronics, Houston, TX (United States)

2008-07-01

Power substations and transmission lines require intelligent (microprocessor-based) electronic devices (IED) for data acquisition, protection, metering, and control. This paper presented a universal transmission line protection relay with segregated phase differential protection as the main function and multiple backup protection functions, including 3 zone distance protection. It described features allowing the application of the IED to multi-terminal lines, mutual coupled lines, charging current compensation, transformer inrush current detection, breaker and a half and ring bus substation configurations. GPS synchronized current differential protection offers reliable protection for transmission and distribution circuits. The security of the protection relay can be improved significantly by combining it with fallback techniques to cover loss of GPS synchronizing, and by including non-differential elements as back-up during route switching and channel failures. 7 figs.

Thermal microwave states acting on a superconducting qubit

Energy Technology Data Exchange (ETDEWEB)

Goetz, Jan; Mueting, Miriam; Haeberlein, Max; Wulschner, Friedrich; Fischer, Michael; Deppe, Frank; Fedorov, Kirill; Huebl, Hans [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, 85748 Garching (Germany); Physik-Department, TU Muenchen, 85748 Garching (Germany); Xie, Edwar; Eder, Peter; Deppe, Frank; Gross, Rudolf [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, 85748 Garching (Germany); Physik-Department, TU Muenchen, 85748 Garching (Germany); Nanosystems Initiative Munich (NIM), Schellingstrasse 4, 80799 Muenchen (Germany); Marx, Achim [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, 85748 Garching (Germany)

2016-07-01

We analyze the influence of broadband thermal states in the microwave regime on the coherence properties of a superconducting (transmon) qubit coupled to a transmission line resonator. We generate the thermal states inside the resonator by heating a 30 dB attenuator to emit blackbody radiation into a transmission line. In the absence of thermal fluctuations, the qubit coherence time is limited by relaxation. We find that the relaxation rate is almost unaffected by the presence of a thermal field inside the resonator. However, such states induce significant dephasing which increases quadratically with the number of thermal photons, whereas for a coherent population of the resonator, the increase shows a linear behavior. These results confirm the different photon statistics, being Poissonian for a coherent population and super-Poissonian for a thermal population of the resonator.

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.

Superconducting on-chip microwave interferometers

Energy Technology Data Exchange (ETDEWEB)

Menzel, Edwin P.; Fischer, Michael; Schneider, Christian; Baust, Alexander; Eder, Peter; Goetz, Jan; Haeberlein, Max; Schwarz, Manuel; Wulschner, Karl Friedrich; Xie, Edwar; Zhong, Ling; Deppe, Frank; Fedorov, Kirill; Huebl, Hans; Marx, Achim; 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

In the realm of all-microwave quantum computation, information is encoded in itinerant microwave photons propagating along transmission lines. In such a system unitary operations are implemented by linear elements such as beam splitters or interferometers. However, for two-qubit operations non-linear gates, e.g., c-phase gates are required. In this work, we investigate superconducting interferometers as a building block of a c-phase gate. We experimentally characterize their scattering properties and compare them to simulation results. Finally, we discuss our progress towards the realization of a c-phase gate.

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.

Magnetic insulation in triplate and coaxial vacuum transmission lines. Report PIFR-1009

International Nuclear Information System (INIS)

Di Capua, M.; Pellinen, D.G.

1980-08-01

An experimental investigation was made of magnetically insulated transmission lines for use in an electron beam fusion accelerator. The magnetically insulated vacuum transmission lines would transfer the power pulses from many modules to a single diode region or multiple diodes to generate currents on the order of 100 MA. This approach may allow present limits on power flow through dielectric vacuum interfaces to be overcome. We have investigated symmetric parallel plate (triplate) transmission lines with a wave impedance of 24 Ω and a spacing of 1.9 cm, and coaxial transmission lines (coax) with a wave impedance of 42 Ω and a spacing of 2.9 cm

Environmental pollution by magnetic field associated with power transmission lines

Energy Technology Data Exchange (ETDEWEB)

Hamza, Abdel-Salam H. A.; Ghania, Samy M. [Faculty of Engineering, Zagazig University (Banha Branch), 9-EI-Hakim Be-Amr EI-Ahh Str, EI- Khalafawy, Shoubra, Cairo (Egypt); Mohmoudh, Shaher A. [Ministry of Electricity and Energy (Egypt)

2002-11-01

Environmental pollution has a major effect on human health and other life types. A source of environmental pollution is the magnetic field produced near high and extra high voltage (EHV) transmission lines. Magnetic fields from AC EHV lines have been discussed in this paper. The field profiles and their contribution to environmental pollution are studied, these being under transmission lines with different line system configurations, using the three dimensional approaches. These line system configurations are more commonly used in Egypt and other countries. The obtained results are found to be useful for discussing the comparison of the field densities on the human body and other life types at the ground level under or near the lines. (Author)

Coaxial tube array space transmission line characterization

International Nuclear Information System (INIS)

Switzer, C.A.; Bents, D.J.

1987-01-01

The coaxial tube array tether/transmission line used to connect an SP-100 nuclear power system to the space station was characterized over the range of reactor-to-platform separation distances of 1 to 10 km. Characterization was done with respect to array performance, physical dimensions and masses. Using a fixed design procedure, a family of designs was generated for the same power level (300 kWe), power loss (1.5 percent), and meteoroid survival probability (99.5 percent over 10 yr). To differentiate between vacuum insulated and gas insulated lines, two different maximum values of the E field were considered: 20 kV/cm (appropriate to vacuum insulation) and 50 kV/cm (compressed SF6). Core conductor, tube, bumper, standoff, spacer and bumper support dimensions, and masses were also calculated. The results of the characterization show mainly how transmission line size and mass scale with reactor-to-platform separation distance

Superconducting nanostructured materials

International Nuclear Information System (INIS)

Metlushko, V.

1998-01-01

Within the last year it has been realized that the remarkable properties of superconducting thin films containing a periodic array of defects (such as sub-micron sized holes) offer a new route for developing a novel superconducting materials based on precise control of microstructure by modern photolithography. A superconductor is a material which, when cooled below a certain temperature, loses all resistance to electricity. This means that superconducting materials can carry large electrical currents without any energy loss--but there are limits to how much current can flow before superconductivity is destroyed. The current at which superconductivity breaks down is called the critical current. The value of the critical current is determined by the balance of Lorentz forces and pinning forces acting on the flux lines in the superconductor. Lorentz forces proportional to the current flow tend to drive the flux lines into motion, which dissipates energy and destroys zero resistance. Pinning forces created by isolated defects in the microstructure oppose flux line motion and increase the critical current. Many kinds of artificial pinning centers have been proposed and developed to increase critical current performance, ranging from dispersal of small non-superconducting second phases to creation of defects by proton, neutron or heavy ion irradiation. In all of these methods, the pinning centers are randomly distributed over the superconducting material, causing them to operate well below their maximum efficiency. We are overcome this drawback by creating pinning centers in aperiodic lattice (see Fig 1) so that each pin site interacts strongly with only one or a few flux lines

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...

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

E-Textile Embroidered Metamaterial Transmission Line for Signal Propagation Control

Directory of Open Access Journals (Sweden)

Bahareh Moradi

2018-06-01

Full Text Available In this paper, the utilization of common fabrics for the manufacturing of e-textile metamaterial transmission lines is investigated. In order to filter and control the signal propagation in the ultra-high frequency (UHF range along the e-textile, a conventional metamaterial transmission line was compared with embroidered metamaterial particles. The proposed design was based on a transmission line loaded with one or several split-ring resonators (SRR on a felt substrate. To explore the relations between physical parameters and filter performance characteristics, theoretical models based on transmission matrices’ description of the filter constituent components were proposed. Excellent agreement between theoretical prediction, electromagnetic simulations, and measurement were found. Experimental results showed stop-band levels higher than −30 dB for compact embroidered metamaterial e-textiles. The validated results confirmed embroidery as a useful technique to obtain customized electromagnetic properties, such as filtering, on wearable applications.

E-Textile Embroidered Metamaterial Transmission Line for Signal Propagation Control.

Science.gov (United States)

Moradi, Bahareh; Fernández-García, Raul; Gil, Ignacio

2018-06-05

In this paper, the utilization of common fabrics for the manufacturing of e-textile metamaterial transmission lines is investigated. In order to filter and control the signal propagation in the ultra-high frequency (UHF) range along the e-textile, a conventional metamaterial transmission line was compared with embroidered metamaterial particles. The proposed design was based on a transmission line loaded with one or several split-ring resonators (SRR) on a felt substrate. To explore the relations between physical parameters and filter performance characteristics, theoretical models based on transmission matrices' description of the filter constituent components were proposed. Excellent agreement between theoretical prediction, electromagnetic simulations, and measurement were found. Experimental results showed stop-band levels higher than -30 dB for compact embroidered metamaterial e-textiles. The validated results confirmed embroidery as a useful technique to obtain customized electromagnetic properties, such as filtering, on wearable applications.

Stationary levitation and vibration transmission characteristic in a superconducting seismic isolation device with a permanent magnet system and a copper plate

Energy Technology Data Exchange (ETDEWEB)

Sasaki, S., E-mail: s.sasaki@ecei.tohoku.ac.j [Electrical Engineering Department, Graduate School, Tohoku University, 6-6-05 Aoba Aramaki, Aoba-ku, Sendai, Miyagi 980-8579 (Japan); Shimada, K.; Yagai, T.; Tsuda, M.; Hamajima, T. [Electrical Engineering Department, Graduate School, Tohoku University, 6-6-05 Aoba Aramaki, Aoba-ku, Sendai, Miyagi 980-8579 (Japan); Kawai, N.; Yasui, K. [Okumura Corporation, 5-6-1 Shiba, Minato-ku, Tokyo 180-8381 (Japan)

2010-11-01

We have devised a magnetic levitation type superconducting seismic isolation device taking advantage of the specific characteristic of HTS bulk that the HTS bulk returns to its original position by restoring force against a horizontal displacement. The superconducting seismic isolation device is composed of HTS bulks and permanent magnets (PM rails). The PMs are fixed on an iron plate to realize the same polarities in the longitudinal direction and the different polarities in the transverse direction. The superconducting seismic isolation device can theoretically remove any horizontal vibrations completely. Therefore, the vibration transmissibility in the longitudinal direction of the PM rail becomes zero in theory. The zero vibration transmissibility and the stationary levitation, however, cannot be achieved in the real device because a uniform magnetic field distribution in the longitudinal direction of PM rail cannot be realized due to the individual difference of the PMs. Therefore, to achieve stationary levitation in the real device we adopted a PM-PM system that the different polarities are faced each other. The stationary levitation could be achieved by the magnetic interaction between the PMs in the PM-PM system, while the vibration transmitted to the seismic isolation object due to the magnetic interaction. We adopted a copper plate between the PMs to reduce the vibration transmissibility. The PM-PM system with the copper plate is very useful for realizing the stationary levitation and reducing the vibration transmissibility.

Stationary levitation and vibration transmission characteristic in a superconducting seismic isolation device with a permanent magnet system and a copper plate

International Nuclear Information System (INIS)

Sasaki, S.; Shimada, K.; Yagai, T.; Tsuda, M.; Hamajima, T.; Kawai, N.; Yasui, K.

2010-01-01

We have devised a magnetic levitation type superconducting seismic isolation device taking advantage of the specific characteristic of HTS bulk that the HTS bulk returns to its original position by restoring force against a horizontal displacement. The superconducting seismic isolation device is composed of HTS bulks and permanent magnets (PM rails). The PMs are fixed on an iron plate to realize the same polarities in the longitudinal direction and the different polarities in the transverse direction. The superconducting seismic isolation device can theoretically remove any horizontal vibrations completely. Therefore, the vibration transmissibility in the longitudinal direction of the PM rail becomes zero in theory. The zero vibration transmissibility and the stationary levitation, however, cannot be achieved in the real device because a uniform magnetic field distribution in the longitudinal direction of PM rail cannot be realized due to the individual difference of the PMs. Therefore, to achieve stationary levitation in the real device we adopted a PM-PM system that the different polarities are faced each other. The stationary levitation could be achieved by the magnetic interaction between the PMs in the PM-PM system, while the vibration transmitted to the seismic isolation object due to the magnetic interaction. We adopted a copper plate between the PMs to reduce the vibration transmissibility. The PM-PM system with the copper plate is very useful for realizing the stationary levitation and reducing the vibration transmissibility.

Development of an Ethernet enabled microcontroller based module for Superconducting Cyclotron ECR beam line control

International Nuclear Information System (INIS)

Chatterjee, M.; Koley, D.; Nabhiraj, P.Y.

2012-01-01

An Ethernet enabled control and data acquisition module is developed for remote control and monitoring of the ECR beam line equipment of the Superconducting Cyclotron. The PIC microcontroller based module supports multiple general purpose analog and digital inputs and outputs for interfacing with various equipments and an embedded web server. The remote monitoring and control of the equipment are achieved through the web based user interface. The user authenticated access to control parameters and module configuration parameters ensures the operational safety of the equipment under control. This module is installed in Superconducting Cyclotron ECR beam line for the control and monitoring of vacuum pumping modules, comprising of pumps, gate valves and dual vacuum gauges. The installation of these modules results in a distributed control with localised field cabling and hence better fault diagnosis. (author)

Improvement in operational characteristics of KEPCO’s line-commutation-type superconducting hybrid fault current limiter

International Nuclear Information System (INIS)

Yim, S.-W.; Park, B.-C.; Jeong, Y.-T.; Kim, Y.-J.; Yang, S.-E.; Kim, W.-S.; Kim, H.-R.; Du, H.-I.

2013-01-01

Highlights: ► A line-commutation type hybrid FCL was modified for 1st peak current limitation. ► A superconducting module of current limitation and fault detection was fabricated. ► The superconducting module was applied to a hybrid FCL system and tested. ► 7.4 kA p fault current was limited to 4.3 kA p at the first-half cycle by the FCL. -- Abstract: A 22.9 kV class hybrid fault current limiter (FCL) developed by Korea Electric Power Corporation and LS Industrial Systems in 2006 operates using the line commutation mechanism and begins to limit the fault current after the first half-cycle. The first peak of the fault current is available for protective coordination in the power system. However, it also produces a large electromagnetic force and imposes a huge stress on power facilities such as the main transformer and gas-insulated switchgear. In this study, we improved the operational characteristics of the hybrid FCL in order to reduce the first peak of the fault current. While maintaining the structure of the hybrid FCL system, we developed a superconducting module that detects and limits the fault current during the first half-cycle. To maintain the protective coordination capacity, the hybrid FCL was designed to reduce the first peak value of the fault current by up to approximately 30%. The superconducting module was also designed to produce a minimum AC loss, generating a small, uniform magnetic field distribution during normal operation. Performance tests confirmed that when applied to the hybrid FCL, the superconducting module showed successful current limiting operation without any damage

Superconductivity and fusion energy—the inseparable companions

Science.gov (United States)

Bruzzone, Pierluigi

2015-02-01

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

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.

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.

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.

Submicron superconducting structures

International Nuclear Information System (INIS)

Golovashkin, A.I.; Lykov, A.N.

1986-01-01

An overview of works concerning superconducting structures of submicron dimensions and a system of such structures is given. It is noted that usage of the above structures in superconducting microelectronics permits, first, to increase the element packing density, to decrease the signal transmission time, capacity, power dissipated in high-frequency applications. Secondly, negligible coherence length in transition metals, their alloys and high-temperature compounds also restrict the dimensions of superconducting weak couplings when the 'classical' Josephson effect is displayed. The most effective methods for production of submicron superconducting structures are the following: lithography, double scribering. Recently the systems of superconducting submicron elements are extensively studied. It is shown that such systems can be phased by magnetic field

TLINES: A Computer Program for Circuits of Transmission Lines.

Science.gov (United States)

1983-12-01

of various lengths are handled by stringing together many short lines, with the assumption that each of the longer lines has a length approximated as...expressed in terms of transmission lines numbered from 2 through CAPM , connected in numerical sequence as in figure 3. Line 1 is a dummy element disconnected...from line 2 and the rest of the circuit. Lines 2 through CAPM can each be set to any impedance the user desires. Line CAPM +1 is a zero-impedance line

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).

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)

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

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.

Analysis of line integrated electron density using plasma position data on Korea Superconducting Tokamak Advanced Research

International Nuclear Information System (INIS)

Nam, Y. U.; Chung, J.

2010-01-01

A 280 GHz single-channel horizontal millimeter-wave interferometer system has been installed for plasma electron density measurements on the Korea Superconducting Tokamak Advanced Research (KSTAR) device. This system has a triangular beam path that does not pass through the plasma axis due to geometrical constraints in the superconducting tokamak. The term line density on KSTAR has a different meaning from the line density of other tokamaks. To estimate the peak density and the mean density from the measured line density, information on the position of the plasma is needed. The information has been calculated from tangentially viewed visible images using the toroidal symmetry of the plasma. Interface definition language routines have been developed for this purpose. The calculated plasma position data correspond well to calculation results from magnetic analysis. With the position data and an estimated plasma profile, the peak density and the mean density have been obtained from the line density. From these results, changes of plasma density themselves can be separated from effects of the plasma movements, so they can give valuable information on the plasma status.

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

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

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....... 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....

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.

Limiting characteristics of the superconducting fault current limiter applied to the neutral line of conventional transformer

International Nuclear Information System (INIS)

Im, I.G.; Choi, H.S.; Jung, B.I.

2013-01-01

Highlights: •Fault current limiter was used a high-speed interrupter. •High-speed interrupter was operated to bypass to the current limiter line. •The size of the fault current was limited to about 80% after the fault occurred. •The fault current was limited quickly within a half-cycle after the fault occurred. -- Abstract: The increased electricity demands influenced by the recent industrial development make the electric power distribution system more comprehensive, and the risks are high to cause failures to steady state electric line due to the extended range of fault at the time of fault occurrence. Also, the high performance and the high precision electric appliances that sensitive to switching surge and fault current expose vulnerability of reduced life span and increased fault occurrence ratio. Therefore, this thesis analyzed the fault limiting characteristics by the fault types by applying the superconducting fault current limiter to the neutral line of the transformer in order to reduce the fault currents that flow such high performance appliances. A current transformer (CT) that detects the fault current in the simulated power distribution system, a switching control system that is self-developed and a transformer are used in constructing a circuit. When a fault occurs, the initial fault current is restricted by the superconducting fault current limiter and simultaneously detours the fault current by operating the SCR contact of the switching control system through the detection by CT. This thesis analyzed the limiting characteristics of the superconducting fault current limiter that are applied to the neutral line of the transformer by the fault types

Limiting characteristics of the superconducting fault current limiter applied to the neutral line of conventional transformer

Energy Technology Data Exchange (ETDEWEB)

Im, I.G., E-mail: asiligo@gmail.com; Choi, H.S., E-mail: hyosang@chosun.ac.kr; Jung, B.I.

2013-11-15

Highlights: •Fault current limiter was used a high-speed interrupter. •High-speed interrupter was operated to bypass to the current limiter line. •The size of the fault current was limited to about 80% after the fault occurred. •The fault current was limited quickly within a half-cycle after the fault occurred. -- Abstract: The increased electricity demands influenced by the recent industrial development make the electric power distribution system more comprehensive, and the risks are high to cause failures to steady state electric line due to the extended range of fault at the time of fault occurrence. Also, the high performance and the high precision electric appliances that sensitive to switching surge and fault current expose vulnerability of reduced life span and increased fault occurrence ratio. Therefore, this thesis analyzed the fault limiting characteristics by the fault types by applying the superconducting fault current limiter to the neutral line of the transformer in order to reduce the fault currents that flow such high performance appliances. A current transformer (CT) that detects the fault current in the simulated power distribution system, a switching control system that is self-developed and a transformer are used in constructing a circuit. When a fault occurs, the initial fault current is restricted by the superconducting fault current limiter and simultaneously detours the fault current by operating the SCR contact of the switching control system through the detection by CT. This thesis analyzed the limiting characteristics of the superconducting fault current limiter that are applied to the neutral line of the transformer by the fault types.

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

Suppression of multipacting in high power RF couplers operating with superconducting cavities

Energy Technology Data Exchange (ETDEWEB)

Ostroumov, P.N., E-mail: ostroumov@frib.msu.edu [Facility for Rare Isotope Beams (FRIB), Michigan State University, East Lansing, MI 48824 (United States); Kazakov, S. [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Morris, D.; Larter, T.; Plastun, A.S.; Popielarski, J.; Wei, J.; Xu, T. [Facility for Rare Isotope Beams (FRIB), Michigan State University, East Lansing, MI 48824 (United States)

2017-06-01

Capacitive input couplers based on a 50 Ω coaxial transmission line are frequently used to transmit RF power to superconducting (SC) resonators operating in CW mode. It is well known that coaxial transmission lines are prone to multipacting phenomenon in a wide range of RF power level and operating frequency. The Facility for Rare Isotope Beams (FRIB) being constructed at Michigan State University includes two types of quarter wave SC resonators (QWR) operating at 80.5 MHz and two types of half wave SC resonators (HWR) operating at 322 MHz. As was reported in ref. [1] a capacitive input coupler used with HWRs was experiencing strong multipacting that resulted in a long conditioning time prior the cavity testing at design levels of accelerating fields. We have developed an insert into 50 Ω coaxial transmission line that provides opportunity to bias the RF coupler antenna and protect the amplifier from the bias potential in the case of breakdown in DC isolation. Two of such devices have been built and are currently used for the off-line testing of 8 HWRs installed in the cryomodule.

Semiannual report for the period October 1, 1979-March 31, 1980 of work on: (1) superconducting power transmission system development; (2) cable insulation development. Power Transmission Project Technical Note No. 106

Energy Technology Data Exchange (ETDEWEB)

1980-07-07

Progress is reported in a program whose objective is to develop an underground superconducting power transmission system which is economical and technically attractive to the utility industry. The system would be capable of carrying very large blocks of electric power, and would supplant overhead lines in urban and suburban areas and regions of natural beauty. The program consisted initially of work in the laboratory to develop suitable materials, cryostats, and cable concepts. The materials work covers the development and testing of suitable superconductors and dielectric insulation. The laboratory work has now been extended to an outside test facility which represents an intermediate step between the laboratory scale and a full-scale system. The facility will allow cables several hundred feet long to be tested under realistic conditions. In addition, the refrigerator has been designed for optimum service for utility applications.

Off-line tests of superconducting resonators of the JAERI tandem booster

International Nuclear Information System (INIS)

Shibata, Michihiro; Ishii, Tetsuro; Takeuchi, Suehiro

1993-01-01

The JAERI tandem booster linac, which consists of 46 superconducting quarter wave resonators, is under construction. Off-line tests for resonators were performed. Accelerating field levels of 7MV/m were obtained at an rf input of 4W with most resonators. A maximum field level of 12.7MV/m was obtained. The Q-value was degraded when resonators were cooled down slowly around a temperature of 120K. We investigated this phenomenon by changing the cooling rate. (author)

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

Development of superconducting equipment for fusion device

International Nuclear Information System (INIS)

Konno, Masayuki; Ueda, Toshio; Hiue, Hisaaki; Ohgushi, Kouzou

1993-01-01

At Fuji Electric Co., Ltd., the development of superconductivity was started from 1960, and superconducting equipment for fusion device has been developed for ten years. The superconducting equipment, which is developed for fusion by Fuji Electric Co., Ltd., are able to be grouped in three categories which are current lead, superconducting coil and superconducting bus-line. The current lead is an electrical feeder between a superconducting coil and an electrical power supply. The rated current of developed current lead is 30kA at continuous use and 100kA at short time use respectively. The advanced disk type coil is developed for the toroidal field coil and some coils are developed for critical current measurement. Superconductor is applied to the superconducting bus-line between the superconducting coils and the current leads, and the bus-line is being developed for the Large Helical Device. This report describes an abstract of these equipment. (author)

Application of superconductors to motors, generators, and transmission lines

International Nuclear Information System (INIS)

Kirtley, J.L.

1989-01-01

Superconductors are of interest to the designers of electric power equipment because they can carry current without loss, currents that are large enough to make very intense magnetic fields. This means that superconductors, used in suitable applications, can make electric power equipment smaller, lighter, more efficient, and perhaps with better dynamic response. Two specific applications are considered here: electric machinery (motors and generators) and transmission lines. The so-called high-T c superconductors will have beneficial impact on motors, generators, and transmission lines only if conductors with sufficient mechanical properties and current-carrying capabilities can be developed

Dynamic Model for the Z Accelerator Vacuum Section Based on Transmission Line Code%Dynamic Model for the Z Accelerator Vacuum Section Based on Transmission Line Code

Institute of Scientific and Technical Information of China (English)

呼义翔; 雷天时; 吴撼宇; 郭宁; 韩娟娟; 邱爱慈; 王亮平; 黄涛; 丛培天; 张信军; 李岩; 曾正中; 孙铁平

2011-01-01

The transmission-line-circuit model of the Z accelerator, developed originally by W. A. STYGAR, P. A. CORCORAN, et al., is revised. The revised model uses different calculations for the electron loss and flow impedance in the magnetically insulated transmission line system of the Z accelerator before and after magnetic insulation is established. By including electron pressure and zero electric field at the cathode, a closed set of equations is obtained at each time step, and dynamic shunt resistance （used to represent any electron loss to the anode） and flow impedance are solved, which have been incorporated into the transmission line code for simulations of the vacuum section in the Z accelerator. Finally, the results are discussed in comparison with earlier findings to show the effectiveness and limitations of the model.

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...

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

A universal calculation model for the controlled electric transmission line

International Nuclear Information System (INIS)

Zivzivadze, O.; Zivzivadze, L.

2009-01-01

Difficulties associated with the development of calculation models are analyzed, and the ways of resolution of these problems are given. A version of the equivalent circuit as a six-pole network, the parameters of which do not depend on the angle of shift Θ between the voltage vectors of circuits is offered. The interrelation between the parameters of the equivalent circuit and the transmission constants of the line was determined. A universal calculation model for the controlled electric transmission line was elaborated. The model allows calculating the stationary modes of lines of such classes at any angle of shift Θ between the circuits. (author)

Sensor Placement For Structural Monitoring of Transmission Line Towers

Directory of Open Access Journals (Sweden)

Benny eRaphael

2015-11-01

Full Text Available Transmission line towers are usually analyzed using linear elastic idealized truss models. Due to the assumptions used in the analysis, there are discrepancies between the actual results obtained from full scale prototype testing and the analytical results. Therefore, design engineers are interested in assessing the actual stress levels in transmission line towers. Since it is costly to place sensors on every member of a tower structure, the best locations for sensors need to be carefully selected. This study evaluates a methodology for sensor placement in transmission line towers. The objective is to find optimal locations for sensors such that the real behavior of the structure can be explained from measurements. The methodology is based on the concepts of entropy and model falsification. Sensor locations are selected based on maximum entropy such that there is maximum separation between model instances that represent different possible combinations of parameter values which have uncertainties. The performance of the proposed algorithm is compared to that of an intuitive method in which sensor locations are selected where the forces are maximum. A typical 220 kV transmission tower is taken as case study in this paper. It is shown that the intuitive method results in much higher number of non-separable models compared to the optimal sensor placement algorithm. Thus the intuitive method results in poor identification of the system.

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.

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

Energy Technology Data Exchange (ETDEWEB)

Klofai, Yerima [Department of Physics, Higher Teacher Training College, University of Maroua, PO Box 46 Maroua (Cameroon); Essimbi, B Z [Department of Physics, Faculty of Science, University of Yaounde 1, PO Box 812 Yaounde (Cameroon); Jaeger, D, E-mail: bessimb@yahoo.fr [ZHO, Optoelectronik, Universitaet Duisburg-Essen, D-47048 Duisburg (Germany)

2011-10-15

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.

Mass and loss analysis of a space-type radiation cooled insulated DC transmission line

International Nuclear Information System (INIS)

Schwarze, g.E.

1986-01-01

As both the power levels and transmission distances increase such as for large future nuclear power systems, the transmission line becomes an important element in the power chain between the source and load bus. Thus, the transmission line's characteristics must be determined so that the effect of these characteristics on the total power system can be assessed. These design characteristics include the specific mass, percent power loss, size, voltage and power levels, and operating temperatures of the conductor and insulating materials. In a previous paper, the dc transmission line's characteristics of a noninsulated solid cylindrical conductor were determined. In that analysis the expression derived for the transmission line's mass only included the conductor mass and the operating temperature of the line was that of the conductor. In the analysis of this paper, a single layer of insulation is added to the solid cylindrical conductor. In this analysis the dependency of the dc transmission line's mass, loss, and size on the power and voltage levels, conductor and insulation surface temperatures, transmission distance, and conductor and insulation material properties is determined. This analysis can be extended to multi-layers of insulation but the complexity of the analysis increases as the number of layers increase

Design of Miniaturized 10dB Wideband Branch Line Coupler Using Dual and T-Shape Transmission Lines

Directory of Open Access Journals (Sweden)

M. Kumar

2018-04-01

Full Text Available This paper presents a design mechanism of miniaturized wideband branch line coupler (BLC with loose coupling of 10 dB. Dual transmission lines are used as a feed network which provides a size reduction of 32% with a fractional bandwidth (FBW of 60% for 10±0.5 dB coupling but return loss performance is found to be poor in the operating band. For further improvement of return loss performance as well as for size reduction of the BLC, a T- shape transmission lines are used instead of series quarter wavelength transmission lines, and hence the overall size reduction of around 44% with FBW of 50.4% is achieved. The return loss and isolation performance is found to be les than 15 dB in the entire operating band (2.5–4.1 GHz with respect to design frequency 3G Hz. The proposed BLC is analyzed, fabricated and tested.

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.

Sound Transmission Through Multi-Panel Structures Lined with Elastic Porous Materials

Science.gov (United States)

Bolton, J. S.; Shiau, N.-M.; Kang, Y. J.

1996-04-01

Theory and measurements related to sound transmission through double panels lined with elastic porous media are presented. The information has application to the design of noise control barriers and to the optimization of aircraft fuselage transmission loss, for example. The major difference between the work described here and earlier research in this field relates to the treatment of the porous material that is used to line the cavity between the two panels of the double panel structure. Here we have used the porous material theory proposed by Biot since it takes explicit account of all the wave types known to propagate in elastic porous materials. As a result, it is possible to use the theory presented here to calculate the transmission loss of lined double panels at arbitrary angles of incidence; results calculated over a range of incidence angles may then be combined to yield the random incidence transmission loss. In this paper, the equations governing wave propagation in an elastic porous material are first considered briefly and then the general forms for the stresses and displacements within the porous material are given. Those solutions are expressed in terms of a number of constants that can be determined by application of appropriate boundary conditions. The boundary conditions required to model double panels having linings that are either directly attached to the facing panels or separated?!from them by air gaps are presented and discussed. Measurements of the random incidence transmission loss of aluminium double-panel structures lined with polyurethane foam are presented and have been found to be in good agreement with theoretical predictions. Both the theoretical predictions and the measured results have shown that the method by which an elastic porous lining material is attached to the facing panels can have a profound influence on the transmission loss of the panel system. It has been found, for example, that treatments in which the lining material

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.

Superconductive crossbar system for communication applications

International Nuclear Information System (INIS)

Murdock, B.; Kwong, Y.K.; Gimlett, J.

1994-01-01

This paper reviews current efforts toward the integration of a high-speed crossbar switch for digital communication applications. This system is an intelligent switching matrix for 128 inputs and 128 outputs, each capable of 2 Gbs (10 9 bits per second). An array of Josephson junction integrated circuits are interconnected with the use of a superconductive multichip module maintained at 4.2 K. This module is connected to room-temperature electronics by means of flexible cables, each containing impedance-matched microstrip transmission lines. Room-temperature interface electronics will permit interconversion between standard level input/output signals and Josephson junction logic levels. (orig.)

Characteristic analysis of coupled transmission lines in stripline-type beam position monitor

International Nuclear Information System (INIS)

Suwada, T.

2013-01-01

Signal transmission characteristics in stripline electrodes of a stripline-type beam position monitor (BPM) are discussed on the basis of a coupled-mode analysis in electromagnetically coupled transmission lines. The physical prospect in the calibration procedure of stripline electrodes is improved in terms of signal transmission characteristics in the frequency domain. It is demonstrated that in the signal transmission with electromagnetic coupling between the stripline electrodes, the magnetic- and electric-coupling parameters play an important role depending upon the spatial configuration and mechanical structure of the stripline electrodes. In this report, a theoretical analysis, and experimental investigation into signal transmission characteristics and performance in a standard stripline-type BPM are described in detail on the basis of a coupled-mode analysis in uniform transmission lines

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.

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.

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.

Superconducting coil manufacturing method for low current dc beam line magnets

International Nuclear Information System (INIS)

Satti, J.A.

1977-01-01

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

Manitoba Hydro long-term high-voltage transmission line magnetic field monitoring project

International Nuclear Information System (INIS)

Wong, P.S.; Ng, C.K.

2008-01-01

As part of the licensing process to construct a new 230 kV transmission line on an existing right-of-way in Manitoba, an electrical effects study was conducted in 1998. The study was part of the environmental assessment program crucial in obtaining government approval to construct the line. Some residents living adjacent to the new transmission circuit expressed concerns about alleged adverse health effects associated with long-term exposure to magnetic fields from high voltage transmission lines. In order to verify the accuracy of the predicted magnetic field levels submitted to the regulatory body in the the electrical effects study and to instill confidence in the residents of the affected communities, a three-year magnetic monitoring project was conducted between 2003 and 2005 along the right-of-way after the new 230kV transmission line was energized by Manitoba Hydro. This paper described the monitoring program, with reference to location; equipment; data analysis; and discussion of results. It was concluded that the long-term monitoring project demonstrated that the magnetic field prediction methodology was well understood and accurate, and provided valuable long-term magnetic field characteristics at the edge of the right-of-way. In addition, when there is opposition to a transmission line, public consultation and education were found to be the best options to arrive at a solution. 3 refs., 1 tab., 12 figs

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

African Journals Online (AJOL)

Yomi

2010-08-18

Aug 18, 2010 ... transmission lines on ornamental plant growth. Zeki Demir ... The effects of proximity to power-line on specific leaf area and seedling dbh were tested .... during vegetation season is about 72% and common wind blow.

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.

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

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

The development of superconducting equipment

CERN Document Server

Ueda, T; Hiue, H

2003-01-01

Fuji Electric has been developing various types of superconducting equipment for over a quarter of a century. This paper describes the development results achieved for superconducting equipment and especially focuses on large-capacity current leads and superconducting transmission systems, the development of which is being promoted for application to the field of nuclear fusion. High temperature superconductor (HTS) is becoming the mainstream in the field of superconductivity, and the HTS floating coil and conduction-cooled HTS transformed are also introduced as recent developments for devices that utilize this technology. (author)

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.

Superconductivity in technology

International Nuclear Information System (INIS)

Komarek, P.

1976-01-01

Physics, especially high energy physics and solid state physics was the first area in which superconducting magnets were used but in the long run, the most extensive application of superconductivity will probably be in energy technology. Superconducting power transmission cables, magnets for energy conversion in superconducting electrical machines, MHD-generators and fusion reactors and magnets for energy storage are being investigated. Magnets for fusion reactors will have particularly large physical dimensions, which means that much development effort is still needed, for there is no economic alternative. Superconducting surfaces in radio frequency cavities can give Q-values up to a factor of 10 6 higher than those of conventional resonators. Particle accelerators are the important application. And for telecommunication, simple coaxial superconducting radio frequency cables seem promising. The tunnel effect in superconducting junctions is now being developed commercially for sensitive magnetometers and may soon possibly feature in the memory cells of computer devices. Hence superconductivity can play an important role in the technological world, solving physical and technological problems and showing economic advantages as compared with possible conventional techniques, bearing also in mind the importance of reliability and safety. (author)

Superconductivity in power engineering

International Nuclear Information System (INIS)

1989-01-01

This proceedings volume presents 24 conference papers and 15 posters dealing with the following aspects: 1) Principles and elementary aspects of high-temperature superconductivity (3 plenary lectures); 2) Preparation, properties and materials requirements of metallic or oxide superconductors (critical current behaviour, soldered joints, structural studies); 3) Magnet technology (large magnets for thermonuclear fusion devices; magnets for particle accelerators and medical devices); 4) Magnetic levitation and superconductivity; 5) Cryogenics; 6) Energy storage systems using superconducting coils (SMES); 7) Superconducting power transmission cables, switches, transformers, and generator systems for power plant; 8) Supporting activities, industrial aspects, patents. There are thirty-eight records in the ENERGY database relating to individual conference papers. (MM) [de

Infrared hot-electron NbN superconducting photodetectors for imaging applications

International Nuclear Information System (INIS)

Il'in, K.S.; Gol'tsman, G.N.; Verevkin, A.A.; Sobolewski, Roman

1999-01-01

We report an effective quantum efficiency of 340, responsivity >200 A W -1 (>10 4 V W -1 ) and response time of 27±5 ps at temperatures close to the superconducting transition for NbN superconducting hot-electron photodetectors (HEPs) in the near-infrared and optical ranges. Our studies were performed on a few nm thick NbN films deposited on sapphire substrates and patterned into μm-size multibridge detector structures, incorporated into a coplanar transmission line. The time-resolved photoresponse was studied by means of subpicosecond electro-optic sampling with 100 fs wide laser pulses. The quantum efficiency and responsivity studies of our photodetectors were conducted using an amplitude-modulated infrared beam, fibre-optically coupled to the device. The observed picosecond response time and the very high efficiency and sensitivity of the NbN HEPs make them an excellent choice for infrared imaging photodetectors and input optical-to-electrical transducers for superconducting digital circuits. (author)

Interpretation of transmission through type II superconducting thin film on dielectric substrate as observed by laser thermal spectroscopy

Czech Academy of Sciences Publication Activity Database

Šindler, Michal; Tesař, Roman; Koláček, Jan; Skrbek, L.

2012-01-01

Roč. 483, DEC (2012), s. 127-135 ISSN 0921-4534 R&D Projects: GA ČR(CZ) GAP204/11/0015 Grant - others:European Science Foundation(XE) NES, 2007 - 2012 Institutional research plan: CEZ:AV0Z10100521 Keywords : far- infrared transmission * NbN * superconducting film * vortices * terahertz waves Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.718, year: 2012

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)

Change in magnetic induction lines during the current-induced destruction of superconductivity

Energy Technology Data Exchange (ETDEWEB)

Makiei, B; Golab, S; Sikora, A; Troinar, E; Zacharko, W [Polska Akademia Nauk, Wroclaw. Instytut Niskich Temperatur i Badan Strukturalnych

1976-09-01

Recent results of experimental investigations show that during the current-induced destruction of superconductivity in cylindrical samples a non-azimuthal component of the magnetic induction arises. This 'autoparamagnetic effect' is observable both in type I and type II superconductors. Assuming a helical form for the magnetic flux filaments the angle between the magnetic induction lines and the plane perpendicular to the Pb + In alloy sample axis is estimated in several cases. A conceptual explanation of the energy losses in the resistive state is.

800 kW transmission line research at Leatherhead

Energy Technology Data Exchange (ETDEWEB)

1964-05-29

The experimental transmission line was installed at Leatherhead to enable the Central Electricity Research Laboratories to study the insulators, fittings, and conductors likely to be needed for ac power transmission at voltages up to the equivalent of 800 kV three-phase. Continuous recording will be made of corona power loss and radio and television interference. For this purpose C.E.R.L. has developed a statistical radio-interference recorder. The instrumentation also includes an automatic corona-loss bridge and data logger.

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

Energy Technology Data Exchange (ETDEWEB)

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

2016-03-15

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

Discrete PSO algorithm based optimization of transmission lines loading in TNEP problem

International Nuclear Information System (INIS)

Shayeghi, H.; Mahdavi, M.; Bagheri, A.

2010-01-01

Transmission network expansion planning (TNEP) is a basic part of power system planning that determines where, when and how many new transmission lines should be added to the network. Up till now, various methods have been presented to solve the static transmission network expansion planning (STNEP) problem. But in all of these methods, lines adequacy rate has not been considered at the end of planning horizon, i.e. expanded network misses adequacy after some times and needs to be expanded again. 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 discrete particle swarm optimization (DPSO) algorithm. Expanded network will possess a maximum adequacy to provide load demand and also the transmission lines overloaded later. The proposed idea has been tested on the Garvers network and an actual transmission network of the Azerbaijan regional electric company, Iran, and the results are compared with the decimal codification genetic algorithm (DCGA) technique. The results evaluation shows that the network will possess maximum efficiency economically. Also, it is shown that precision and convergence speed of the proposed DPSO based method for the solution of the STNEP problem is superior to DCGA approach.

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.

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

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)

Application of superconducting magnet energy storage to improve power system dynamic performance

International Nuclear Information System (INIS)

Mitani, Y.; Tsuji, K.; Murakami, Y.

1988-01-01

The application of Superconducting Magnet Energy Storage (SMES) to the stabilization of a power system with long distance bulk power transmission lines which has the problem of poorly damped power oscillations, is presented. Control schemes for stabilization using SMES which is capable of controlling active and reactive power simultaneously in four quadrant ranges, is proposed. The effective locations and the necessary capacities of SMES for power system stabilizing control are discussed in detail. Results of numerical analysis and experiments in an artificial power transmission system demonstrate the significant effect of the control by SMES on the improvement of power system oscillatory performance

Radio and television interference caused by corona discharges from high-voltage transmission lines

International Nuclear Information System (INIS)

Sarmadi, M.

1996-01-01

Increase in power utility loads in industrialized countries, as well as developing countries, demands a higher level of transmission line voltage. Radio interference (RI) problems have been determined to be a limiting factor in selecting the size of transmission line conductors. Transmission line noise is primarily caused by corona discharges in the immediate vicinity of the conductor. It has been observed that discharges occur during both half-cycles of the applied voltage, but positive corona is usually predominant at AM radio frequencies range with practical high-voltage and extra high-voltage transmission lines. The corona radio noise effect is highly dependent upon the presence of particles on the surface of the conductor and the increase of the electrical gradient beyond the breakdown value of the air. Therefore, corona radio noise varies significantly with the weather and atmospheric conditions and generally increases by 10 to 30 dB in foul weather

Coupled superconducting resonant cavities for a heavy ion linac

Energy Technology Data Exchange (ETDEWEB)

Shepard, K W [Argonne National Lab., IL (United States); Roy, A [Nuclear Science Center, New Delhi (India)

1992-11-01

A design for a superconducting niobium slow-wave accelerating structure has been explored that may have performance and cost advantages over existing technology. The option considered is an array of pairs of quarter-wave coaxial-line resonant cavities, the two elements of each pair strongly coupled through a short superconducting transmission line. In the linac formed by such an array, each paired structure is independently phased. A disadvantage of two-gap slow wave structures is that each cavity is relatively short, so that a large number of independently-phased elements is required for a linac. Increasing the number of drift tubes per cavity reduces the number of independently-phased elements but at the cost of reducing the range of useful velocity acceptance for each element. Coupling two cavities splits the accelerating rf eigenmode into two resonant modes each of which covers a portion of the full velocity acceptance range of the original, single cavity mode. Using both of these resonant modes makes feasible the use of coupled cavity pairs for a linac with little loss in velocity acceptance. (Author) 2 figs., 8 refs.

Coupled superconducting resonant cavities for a heavy ion linac

International Nuclear Information System (INIS)

Shepard, K.W.; Roy, A.

1992-01-01

A design for a superconducting niobium slow-wave accelerating structure has been explored that may have performance and cost advantages over existing technology. The option considered is an array of pairs of quarter-wave coaxial-line resonant cavities, the two elements of each pair strongly coupled through a short superconducting transmission line. In the linac formed by such an array, each paired structure is independently phased. A disadvantage of two-gap slow wave structures is that each cavity is relatively short, so that a large number of independently-phased elements is required for a linac. Increasing the number of drift tubes per cavity reduces the number of independently-phased elements but at the cost of reducing the range of useful velocity acceptance for each element. Coupling two cavities splits the accelerating rf eigenmode into two resonant modes each of which covers a portion of the full velocity acceptance range of the original, single cavity mode. Using both of these resonant modes makes feasible the use of coupled cavity pairs for a linac with little loss in velocity acceptance. (Author) 2 figs., 8 refs

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.

Terawatt power division and combination using self-magnetically insulated transmission lines

International Nuclear Information System (INIS)

Crow, J.T.; Peterson, G.D.

1980-01-01

Self-magnetically insulated transmission lines are necessary for the efficient transport of the terawatt pulses used in electron and ion accelerators. For some applications it is desirable to divide one transmission line into two, or to combine outputs of two or more lines into one, by means of self-magnetically insulated convolutes. Tests have been made on a coaxial-to-triaxial convolute in which connections between negative inner and outer lines are made by pins passing through holes in the intermediate positive conductor. Measurements in the 2 MV, 400 kA, 40 ns pulse Mite facility indicate virtually 100% current transport through the convolute and the ability to vary the division of current between the inner and outer lines of the triax by choice of inner line impedance. These measurements, and results obtained with this convolute connected to the ion diode for which it was designed, will be presented

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...

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.

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

Magnetically insulated transmission line used for relativistic electron beam injection into SPAC-VI

International Nuclear Information System (INIS)

Tsuzuki, Tetsuya; Narihara, Kazumichi; Tomita, Yukihiro; Mohri, Akihiro.

1980-10-01

For the purpose to inject the electron beam with energy of about 1.5 MeV and current of about 100 kA into the SPAC-6 (torus device), a magnetically insulated transmission line was designed and constructed. The motion of electrons in the line was theoretically analyzed. The requirements for the design of the transmission line were as follows-: (a) condition of magnetic insulation, (b) suppression against reverse gas flow from the beam source to the torus, (c) care to minimize the influence of strong torus magnetic field, (d) reduction of inductance and (e) safety engineering measures, e.g., separation valve in the MITL between the beam source and the SPAC-6. The transmission line of 2.4 m long was designed and constructed. The wave forms of electric potential and current were measured. The transmission efficiency of current along the axis and the efficiency as a function of current at the end of the line were also measured. The reason of the loss of current is discussed. (J.P.N.)

Superconducting devices at Brookhaven National Laboratory

International Nuclear Information System (INIS)

Dahl, P.F.

1978-04-01

The various ongoing programs in applied superconductivity supported by BNL are summarized, including the development of high field ac and dc superconducting magnets for accelerators and other applications, of microwave deflecting cavities for high energy particle beam separators, and of cables for underground power transmission, and materials research on methods of fabricating new superconductors and on metallurgical properties affecting the performance of superconducting devices

High power RF transmission line component development

International Nuclear Information System (INIS)

Hong, B. G.; Hwang, C. K.; Bae, Y. D.; Yoon, J. S.; Wang, S. J.; Gu, S. H.; Yang, J. R.; Hahm, Y. S.; Oh, G. S.; Lee, J. R.; Lee, W. I.; Park, S. H.; Kang, M. S.; Oh, S. H.; Lee, W.I.

1999-12-01

We developed the liquid stub and phase shifter which are the key high RF power transmission line components. They show reliable operation characteristics and increased insulation capability, and reduced the size by using liquid (silicon oil, dielectric constant ε=2.72) instead of gas for insulating dielectric material. They do not have finger stock for the electric contact so the local temperature rise due to irregular contact and RF breakdown due to scratch in conductor are prevented. They can be utilized in broadcasting, radar facility which require high RF power transmission. Moreover, they are key components in RF heating system for fusion reactor. (author)

High power RF transmission line component development

Energy Technology Data Exchange (ETDEWEB)

Hong, B. G.; Hwang, C. K.; Bae, Y. D.; Yoon, J. S.; Wang, S. J.; Gu, S. H.; Yang, J. R.; Hahm, Y. S.; Oh, G. S.; Lee, J. R.; Lee, W. I.; Park, S. H.; Kang, M. S.; Oh, S. H.; Lee, W.I

1999-12-01

We developed the liquid stub and phase shifter which are the key high RF power transmission line components. They show reliable operation characteristics and increased insulation capability, and reduced the size by using liquid (silicon oil, dielectric constant {epsilon}=2.72) instead of gas for insulating dielectric material. They do not have finger stock for the electric contact so the local temperature rise due to irregular contact and RF breakdown due to scratch in conductor are prevented. They can be utilized in broadcasting, radar facility which require high RF power transmission. Moreover, they are key components in RF heating system for fusion reactor. (author)

Sound transmission through triple-panel structures lined with poroelastic materials

Science.gov (United States)

Liu, Yu

2015-03-01

In this paper, previous theories on the prediction of sound transmission loss for a double-panel structure lined with poroelastic materials are extended to address the problem of a triple-panel structure. Six typical configurations are considered for a triple-panel structure based on the method of coupling the porous layers to the facing panels which determines critically the sound insulation performance of the system. The transfer matrix method is employed to solve the system by applying appropriate types of boundary conditions for these configurations. The transmission loss of the triple-panel structures in a diffuse sound field is calculated as a function of frequency and compared with that of corresponding double-panel structures. Generally, the triple-panel structure with poroelastic linings has superior acoustic performance to the double-panel counterpart, remarkably in the mid-high frequency range and possibly at low frequencies, by selecting appropriate configurations in which those with two air gaps in the structure exhibit the best overall performance over the entire frequency range. The poroelastic lining significantly lowers the cut-on frequency above which the triple-panel structure exhibits noticeably higher transmission loss. Compared with a double-panel structure, the wider range of system parameters for a triple-panel structure due to the additional partition provides more design space for tuning the sound insulation performance. Despite the increased structural complexity, the triple-panel structure lined with poroelastic materials has the obvious advantages in sound transmission loss while without the penalties in weight and volume, and is hence a promising replacement for the widely used double-panel sandwich structure.

Stacked magnet superconducting bearing

International Nuclear Information System (INIS)

Rigney, T.K. II; Saville, M.P.

1993-01-01

A superconducting bearing is described, comprising: a plurality of permanent magnets magnetized end-to-end and stacked side-by-side in alternating polarity, such that flux lines flow between ends of adjacent magnets; isolating means, disposed between said adjacent magnets, for reducing flux leakage between opposing sides of said adjacent magnets; and a member made of superconducting material having at least one surface in communication with said flux lines

Numerical noise analysis for insulator of overhead transmission line

Science.gov (United States)

Zhang, Yulin; Chen, Yuwen; Huang, Yu

2018-04-01

As an important and complex issue in aero acoustic field, a lot of explorations have been devoted to the wind-induced noise. However, there is still lack of intensive investigations for aerodynamic noise in high-voltage transmission. The overhead transmission line system leads to serious occupational noise exposure in high wind-speed environment, and the noise can even injure the electricians in charge of insulator. By using computational fluid dynamics (CFD) which combined with computational aero acoustics (CAA), this paper predicts the noise generated by insulator of high voltage electricity transmission line which explores in wind environment. The simulation results indicate that the wind velocity, the assembly angle of the insulator and its ribs' distribution are the main contributory factors for the aerodynamic noise. Specifically, when wind velocity is greater than 15m/s, the alteration of noise is not sensitive to the wind velocity; furthermore, when the assembly angle increases from 0°to 60°, the noise decreases gradually, however, if the angle is happening to be 75°or 90°, it would be even greater than that at 0°. In order to inhibit the aerodynamic noise, it is necessary to control the flow blowing across the boundary of the insulator. Consequently, the result indicates that if the outermost rib is shorter than the second one, the noise reduced evidently. This information expects to provide useful help for the extremely suppression of aerodynamic noise, and also supply practical reference material for the design and application of overhead transmission line system.

Structural and superconducting characteristics of YBa2Cu3O7 films grown by fluorine-free metal-organic deposition route

DEFF Research Database (Denmark)

Zhao, Yue; Chu, Jingyuan; Qureishy, Thomas

2018-01-01

Microstructure and superconducting performance of YBa2Cu3O7 (YBCO) films deposited on LaAlO3 single crystal (LAO) substrates by a fluorine-free metal-organic deposition (FF-MOD) technique, have been studied by means of X-ray reciprocal space mapping (RSM), cross-sectional transmission electron mi...... external magnetic field at 77 K. This work offers an in-depth insight into the correlation between the microstructure and superconductivity in the MOD YBCO films.......Microstructure and superconducting performance of YBa2Cu3O7 (YBCO) films deposited on LaAlO3 single crystal (LAO) substrates by a fluorine-free metal-organic deposition (FF-MOD) technique, have been studied by means of X-ray reciprocal space mapping (RSM), cross-sectional transmission electron....... It is suggested that associated partial dislocations formed at the boundary between the stacking faults and YBCO matrix act as strong linear (or dot) pinning centers. These structural characteristics are well in line with the better superconducting performance of the low fluorine-MOD film, in particular under...

Change in magnetic induction lines during the current-induced destruction of superconductivity

Energy Technology Data Exchange (ETDEWEB)

Makiej, B; Golab, S; Sikora, A; Trojnar, E; Zacharko, W

1976-09-01

Recent results of experimental investigations show that during the current-induced destruction of superconductivity in cylindrical samples a non-azimuthal component of the magnetic induction arises. This ''autoparamagnetic effect'' is observable both in type I and type II superconductors. Assuming a helical form for the magnetic flux filaments the angle between the magnetic induction lines and the plane perpendicular to the Pb + In alloy sample axis is estimated in several cases. A conceptual explanation of the energy losses in the resistive state is presented. 4 refs.

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.

North Central Transmission Line: Guidelines for the environmental impact statement

International Nuclear Information System (INIS)

1992-01-01

Guidelines that Manitoba Hydro must follow in the preparation of the environmental impact statement on the proposed North Central Transmission Line (TCTL) project are presented. The project consists of a 138 kV transmission line, two 25 kV distribution lines, and related ancillary structures and facilities. The review process must be sensitive to cultural and community needs and must involve those most directly affected, and should be grounded in the impacted northern communities. The review should include a project background, the proposal, a description of the existing natural and socio-economic environment, and must address employment, education and training, impacts on renewable resource harvesting, environmental impacts, social impacts and economic impacts, legal/jurisdictional issues, infrastructure, mitigation and compensation, and environmental monitoring and follow-up. 1 fig., 20 tabs

Electric and magnetic field reduction by alternative transmission line options

Energy Technology Data Exchange (ETDEWEB)

Stewart, J.R. (Power Technologies, Inc., Schenectady, NY (United States)); Dale, S.J. (Oak Ridge National Lab., TN (United States)); Klein, K.W. (Energetics, Inc., Columbia, MD (United States))

1991-01-01

Ground level electric, and more recently magnetic, fields from overhead power transmission lines are increasingly important considerations in right of way specification, with states setting or planning to set edge of right of way limits. Research has been conducted in high phase order power transmission wherein six of twelve phases are used to transmit power in less physical space and with reduced electrical environmental effects than conventional designs. The first magnetic field testing, as reported in this paper, has verified predictive methods for determination of magnetic fields from high phase order lines. Based on these analytical methods, field profiles have been determined for lines of different phase order of comparable power capacity. Potential advantages of high phase order as a means of field mitigation are discussed. 10 refs., 12 figs., 3 tabs.

Observation of superconducting fluxons by transmission electron microscopy: A Fourier space approach to calculate the electron optical phase shifts and images

International Nuclear Information System (INIS)

Beleggia, M.; Pozzi, G.

2001-01-01

An approach is presented for the calculation of the electron optical phase shift experienced by high-energy electrons in a transmission electron microscope, when they interact with the magnetic field associated with superconducting fluxons in a thin specimen tilted with respect to the beam. It is shown that by decomposing the vector potential in its Fourier components and by calculating the phase shift of each component separately, it is possible to obtain the Fourier transform of the electron optical phase shift, which can be inverted either analytically or numerically. It will be shown how this method can be used to recover the result, previously obtained by the real-space approach, relative to the case of a straight flux tube perpendicular to the specimen surfaces. Then the method is applied to the case of a London fluxon in a thin film, where the bending and the broadening of the magnetic-field lines due to the finite specimen thickness are now correctly taken into account and not treated approximately by means of a parabolic fit. Finally, it will be shown how simple models for the pancake structure of the fluxon can be analyzed within this framework and the main features of electron transmission images predicted

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....... 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....

Superconducting superferric dipole magnet with cold iron core for the VLHC

CERN Document Server

Foster, G W

2002-01-01

Magnetic system of the stage I Very Large Hadron Collider (VLHC) is based on 2 Tesla superconducting magnets with combined functions. These magnets have a room temperature iron yoke with two 20 mm air gaps. Magnetic field in both horizontally separated air gaps is generated by a single, 100 kA superconducting transmission line. An alternative design with a cold iron yoke, horizontally or vertically separated air gaps is under investigation. The cold iron option with horizontally separated air gaps reduces the amount of iron, which is one of the major cost drivers for the 233-km magnet system of future accelerator. The vertical beam separation decreases the superconductor volume, heat load from the synchrotron radiation and eliminates fringe field from the return bus. Nevertheless, the horizontal beam separation provides lowest volume of the iron yoke and, therefore, smaller heat load on the cryogenic system during cooling down. All these options are discussed and compared in the paper. Superconducting correct...

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.

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

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

with the Technical University of Denmark, on how to lessen the visual impact of 400 kV overhead line transmission systems. In this paper omission of shield wires combined with installation of a suitable number of line surge arresters is investigated as a possible alternative to transmission lines equipped...... with shielding wires thereby reducing tower height, allowing more compact designs of towers thus minimizing the visual environment impact of the lines. Omission of shield wires in the system and instead utilizing a larger number of surge arresters in the (upper) phases of an overhead line without reduction...... will be investigated by transient simulations on a 400 kV line with either shield wires or line surge arresters. These simulations will also be used to estimate number and location of the line surge arresters in the line to ensure a satisfactory performance of the line when omitting shield wires in the tower top...

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

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.

Prediction of the Voltage Quality in an Overhead Transmission Line with Distributed Parameters

OpenAIRE

Bulyga Leonid L.; Tarasov Evgeniy V.; Ushakov Vasily Ya.; Kharlov Nikolay N.

2015-01-01

The present work is devoted to investigation of an electrical transmission line with allowance for distributed parameters. From the results of voltage measurements at terminals of an actual transmission line, effective values of the voltage are calculated for every line section. Special attention is given to higher harmonics and asymmetry. Spectral composition of the voltage is presented and changes in values of harmonic components are analyzed. The effect of higher harmonics on the equipment...

Environmental impact of the aerial power transmission lines

International Nuclear Information System (INIS)

Cristescu, D.; Rusan, R.

1993-01-01

In the last 10-12 years the existence of the high voltage lines existence within populated areas has been more and more contested. The paper tries to complete a blank in the Romanian technical literature by introducing the concept of 'line corridor' which is different from the occupied geometric area and from 'the line disturbed corridor'. The concept is meant to specify the area where the high frequency and 50 Hz electromagnetic pollution exceeds some given limits. The impact of the power transmission lines on the human body, due to the effects of the electric and magnetic fields, is considered. Also, the aspects concerning the visual impact, the acoustic and radio noise and the area expensing by the high voltage lines, are considered. International standards and regulations regarding the limitations of this effects are presented. (author)

Location of Faults in Power Transmission Lines Using the ARIMA Method

Directory of Open Access Journals (Sweden)

Danilo Pinto Moreira de Souza

2017-10-01

Full Text Available One of the major problems in transmission lines is the occurrence of failures that affect the quality of the electric power supplied, as the exact localization of the fault must be known for correction. In order to streamline the work of maintenance teams and standardize services, this paper proposes a method of locating faults in power transmission lines by analyzing the voltage oscillographic signals extracted at the line monitoring terminals. The developed method relates time series models obtained specifically for each failure pattern. The parameters of the autoregressive integrated moving average (ARIMA model are estimated in order to adjust the voltage curves and calculate the distance from the initial fault localization to the terminals. Simulations of the failures are performed through the ATPDraw ® (5.5 software and the analyses were completed using the RStudio ® (1.0.143 software. The results obtained with respect to the failures, which did not involve earth return, were satisfactory when compared with widely used techniques in the literature, particularly when the fault distance became larger in relation to the beginning of the transmission line.

Charge imbalance waves and nonequilibrium dynamics near a superconducting phase-slip center

International Nuclear Information System (INIS)

Kadin, A.M.; Smith, L.N.; Skocpol, W.J.

1980-01-01

Using a generalized two-fluid picture to describe a quasi-one-dimensional superconductor near T/sub c/, we provide a heuristic derivation for a set of equations governing the temporal and spatial evolution of the charge imbalance (or branch imbalance) in the quasiparticles. We show that these equations are isomorphic to those that describe a simple electrical transmission line, so that charge imbalance waves may propagate in the superconductor in analogy with electrical signals that propagate down the transmission line. We propose as a model for a phase-slip center in a superconducting filament a localized Josephson oscillator coupled to the transmission line. Applying standard transmission-line theory to solve the problem, we show that the Josephson oscillations in the center generate charge imbalance waves that the propagate out to a frequency-dependent distance of the order of the quasiparticle diffusion length GAMMA/sub Q/*= (Dtau/sub Q/*)/sup 1/2/ before they damp out. The time-averaged behavior of the model reduces to the earlier model of Skocpol, Beasley, and Tinkham. A novel consequence of the model is a prediction of intrinsic hysteresis in the dc current--voltage relation. The model also provides a convenient framework for dealing with ac effects in phase-slip centers, including resonance and synchronization in systems of closely spaced phase-slip centers and microbridges

Storage and on-demand release of microwaves using superconducting resonators with tunable coupling

International Nuclear Information System (INIS)

Pierre, Mathieu; Svensson, Ida-Maria; Raman Sathyamoorthy, Sankar; Johansson, Göran; Delsing, Per

2014-01-01

We present a system which allows to tune the coupling between a superconducting resonator and a transmission line. This storage resonator is addressed through a second, coupling resonator, which is frequency-tunable and controlled by a magnetic flux applied to a superconducting quantum interference device. We experimentally demonstrate that the lifetime of the storage resonator can be tuned by more than three orders of magnitude. A field can be stored for 18 μs when the coupling resonator is tuned off resonance and it can be released in 14 ns when the coupling resonator is tuned on resonance. The device allows capture, storage, and on-demand release of microwaves at a tunable rate.

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.

Frequency Selective Properties of Coaxial Transmission Lines Loaded with Combined Artificial Inclusions

Directory of Open Access Journals (Sweden)

Francisco Falcone

2014-01-01

Full Text Available The properties of a modified coaxial transmission line by periodic inclusions will be discussed. The introduction of split ring resonators, conductor stubs, air gaps, and combination of these gives rise to new frequency selective properties, such as stopband or passband behavior, observable in planar as well as volumetric metamaterial structures. These results envisage new potential applications and implementation of devices in coaxial transmission line technology.

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

Simulation of 6 1/8 inch rigid coaxial RF transmission line

International Nuclear Information System (INIS)

Soni, Atul; Pande, M.M.; Rao, M.K.V.; Handu, V.K.

2006-01-01

A radio frequency (RF) transmission line has been designed based upon rigid coaxial 6 1/8 , 50-ohm line for coupling the RF power from its source to 400 KeV radio frequency quadrupole (RFQ) accelerator. Simulation and analysis have been carried out to evaluate various RF parameters of the line. (author)

Superconducting Nanowires as Nonlinear Inductive Elements for Qubits

OpenAIRE

Ku, Jaseung; Manucharyan, Vladimir; Bezryadin, Alexey

2010-01-01

We report microwave transmission measurements of superconducting Fabry-Perot resonators (SFPR), having a superconducting nanowire placed at a supercurrent antinode. As the plasma oscillation is excited, the supercurrent is forced to flow through the nanowire. The microwave transmission of the resonator-nanowire device shows a nonlinear resonance behavior, significantly dependent on the amplitude of the supercurrent oscillation. We show that such amplitude-dependent response is due to the nonl...

Characteristics of the λ/4 transmission line resonator

International Nuclear Information System (INIS)

Hashimoto, Y.; Masuda, H.; Yoshida, K.; Arai, S.; Niki, K.

1994-01-01

Though the spiral cavity is adequate for low frequency operation, mechanical instability becomes serious for such a low frequency as 20 MHz. We have then studied how to shorten the spiral length by using λ/4 transmission line models. Four models with reduced spiral length are presented. (author)

Semiannual report for the period April 1 to September 30, 1978 of work on: (1) superconducting power transmission system development; (2) cable insulation development. Power Transmission Project technical note No. 83

Energy Technology Data Exchange (ETDEWEB)

1978-11-07

Progress in the development, fabrication and testing of superconductors for HVAC power transmission systems is reported. Information is included on the materials evaluation of superconducting alloys, production of tapes from these alloys, principally Nb/sub 3/Sn cable insulation requirements and development, and the cryogenic equipment used in this research program. (LCL)

Prediction of the Voltage Quality in an Overhead Transmission Line with Distributed Parameters

Directory of Open Access Journals (Sweden)

Bulyga Leonid L.

2015-01-01

Full Text Available The present work is devoted to investigation of an electrical transmission line with allowance for distributed parameters. From the results of voltage measurements at terminals of an actual transmission line, effective values of the voltage are calculated for every line section. Special attention is given to higher harmonics and asymmetry. Spectral composition of the voltage is presented and changes in values of harmonic components are analyzed. The effect of higher harmonics on the equipment operation is analyzed.

Transmission Line for 258 GHz Gyrotron DNP Spectrometry

Science.gov (United States)

Bogdashov, Alexandr A.; Belousov, Vladimir I.; Chirkov, Alexey V.; Denisov, Gregory G.; Korchagin, Vyacheslav V.; Kornishin, Sergey Yu.; Tai, Evgeny M.

2011-06-01

We describe the design and test results of the transmission line for liquid-state (LS) and solid-state (SS) DNP spectrometers with the second-harmonic 258.6 GHz gyrotron at the Institute of the Biophysical Chemistry Center of Goethe University (Frankfurt). The 13-meter line includes a mode converter, HE11 waveguides, 4 mitre bends, a variable polarizer-attenuator, directional couplers, a water-flow calorimeter and a mechanical switch. A microwave power of about 15 W was obtained in the pure HE11 mode at the spectrometer inputs.

Simulation of loss electron in vacuum magnetically insulated transmission lines

International Nuclear Information System (INIS)

Zhang Pengfei; Li Yongdong; Liu Chunliang; Wang Hongguang; Guo Fan; Yang Hailiang; Qiu Aici; Su Zhaofeng; Sun Jianfeng; Sun Jiang; Gao Yi

2011-01-01

In the beginning of magnetic insulated period, loss electron in coaxial vacuum magnetically insulated transmission line (MITL) strikes anode and the bremsstrahlung photons are generated in the mean time. Based on the self-limited flow model, velocity in direction of energy transport, energy spectrum and angular distribution of loss electron are simulated by PIC code, energy spectrum of bremsstrahlung photons as well calculated though Monte Carlo method. Computational results show that the velocity of loss electron is less than 2.998 x 108 m/s, the angular excursion of electron is not much in a board extent of energy spectrum. These results show an indirect diagnosis of vacuum insulted transmission line working status based on loss electron bremsstrahlung. (authors)

Cultural-resource survey report: Hoover Dam Powerplant Modification Project II. Associated transmission-line facility

International Nuclear Information System (INIS)

Queen, R.L.

1991-06-01

The Bureau of Reclamation (Reclamation) is proposing to modify or install additional transmission facilities between the Hoover Dam hydroelectric plant and the Western Area Power Authority substation near Boulder City, Nevada. Reclamation has completed cultural resource investigations to identify historic or prehistoric resources in the project area that might be affected during construction of the transmission line. Four possible transmission corridors approximately 50 feet wide and between 9.5 and 11.5 miles long were investigated. The proposed transmission lines either parallel or replace existing transmission lines. The corridors generally have undergone significant disturbance from past transmission line construction. A Class II sampling survey covering approximately 242 acres was conducted. Access or construction roads have not been identified and surveys of these areas will have to be completed in the future. No historic or prehistoric archeological sites were encountered within the four corridor right-of-ways. It is believed that the probability for prehistoric sites is very low. Four historic period sites were recorded that are outside, but near, the proposed corridor. These sites are not individually eligible for the National Register of Historic Places, but may be associated with the construction of Hoover Dam and contribute to a historic district or multiple property resource area focusing on the dam and its construction

Analytical study for the ability of nonlinear transmission lines to generate solitons

International Nuclear Information System (INIS)

Mostafa, S.I.

2009-01-01

The ability of the nonlinear transmission lines (NLTL) has been studied analytically, in this paper to generate solitons and to cause waveform spreading. This can be achieved by balancing nonlinearity and dispersion. A new technique of improved tanh method (ITM) and improved sech methods (ISM) is applied to the nonlinear partial differential equation that describes the NLTL. It is found that the parameters of the transmission line play an important role in controlling the shape of the soliton.

A distributed parameter model of transmission line transformer for high voltage nanosecond pulse generation.

Science.gov (United States)

Li, Jiangtao; Zhao, Zheng; Li, Longjie; He, Jiaxin; Li, Chenjie; Wang, Yifeng; Su, Can

2017-09-01

A transmission line transformer has potential advantages for nanosecond pulse generation including excellent frequency response and no leakage inductance. The wave propagation process in a secondary mode line is indispensable due to an obvious inside transient electromagnetic transition in this scenario. The equivalent model of the transmission line transformer is crucial for predicting the output waveform and evaluating the effects of magnetic cores on output performance. However, traditional lumped parameter models are not sufficient for nanosecond pulse generation due to the natural neglect of wave propagations in secondary mode lines based on a lumped parameter assumption. In this paper, a distributed parameter model of transmission line transformer was established to investigate wave propagation in the secondary mode line and its influential factors through theoretical analysis and experimental verification. The wave propagation discontinuity in the secondary mode line induced by magnetic cores is emphasized. Characteristics of the magnetic core under a nanosecond pulse were obtained by experiments. Distribution and formation of the secondary mode current were determined for revealing essential wave propagation processes in secondary mode lines. The output waveform and efficiency were found to be affected dramatically by wave propagation discontinuity in secondary mode lines induced by magnetic cores. The proposed distributed parameter model was proved more suitable for nanosecond pulse generation in aspects of secondary mode current, output efficiency, and output waveform. In depth, comprehension of underlying mechanisms and a broader view of the working principle of the transmission line transformer for nanosecond pulse generation can be obtained through this research.

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.

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.

PSpice for filters and transmission lines

CERN Document Server

Tobin, Paul

2007-01-01

In this book, PSpice for Filters and Transmission Lines, we examine a range of active and passive filters where each design is simulated using the latest Cadence Orcad V10.5 PSpice capture software. These filters cannot match the very high order digital signal processing (DSP) filters considered in PSpice for Digital Signal Processing, but nevertheless these filters have many uses. The active filters considered were designed using Butterworth and Chebychev approximation loss functions rather than using the 'cookbook approach' so that the final design will meet a given specification in an exact

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.

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).

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)

Simulation of longitudinal differential protection of transmission lines with additional stabilization and APU system

Directory of Open Access Journals (Sweden)

Rajić Tomislav D.

2016-01-01

Full Text Available This paper explains the algorithm for the longitudinal differential protection of transmission lines with automatic reclosing. Classic stabilization is not sufficient for avoiding of unnecessary operations caused by saturation of current transformer. This problem can occur during the fault plased outside of the protected zone of the transmission line. It is shown how unnecessary operation can occur during the outside fault whithout using of additional stabilization. The different types of faults were simulated and comparison of relay operations with and without additional stabilization is presented. The simulations were performed on the three-phase model of the transmission line formed by using of MATLAB/Simulink program.

Magnetically insulated transmission line oscillator

Science.gov (United States)

Bacon, L.D.; Ballard, W.P.; Clark, M.C.; Marder, B.M.

1987-05-19

A magnetically insulated transmission line oscillator employs self-generated magnetic fields to generate microwave energy. An anode of the oscillator includes slow-wave structures which are formed of a plurality of thin conductive vanes defining cavities therebetween, and a gap is formed between the anode and a cathode of the oscillator. In response to a pulsed voltage applied to the anode and cathode, self-generated magnetic fields are produced in a cross-field orientation with respect to the orientation of the electric field between the anode and the cathode. The cross-field magnetic fields insulate the flow of electrons in the gap and confine the flow of electrons within the gap. 11 figs.

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

International Nuclear Information System (INIS)

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

2017-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2017-06-15

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

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.

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

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.

Experimental transmission electron microscopy studies and phenomenological model of bismuth-based superconducting compounds

International Nuclear Information System (INIS)

Elboussiri, Khalid

1991-01-01

The main part of this thesis is devoted to an experimental study by transmission electron microscopy of the different phases of the superconducting bismuth cuprates Bi_2Sr_2Ca_n_-_1Cu_nO_2_n_+_4. In high resolution electron microscopy, the two types of incommensurate modulation realized in these compounds have been observed. A model of structure has been proposed from which the simulated images obtained are consistent with observations. The medium resolution images correlated with the electron diffraction data have revealed existence of a multi-soliton regime with latent lock in phases of commensurate periods between 4b and 10b. At last, a description of different phases of these compounds as a result of superstructures from a disordered perovskite type structure is proposed (author) [fr

Analytical methods for study of transmission line lightning protection

International Nuclear Information System (INIS)

Pettersson, Per.

1993-04-01

Transmission line lightning performance is studied by analytical methods. The elements of shielding failure flashovers and back-flashovers are analysed as functions of incidence, response and insulation. Closed-form approximate expressions are sought to enhance understanding of the phenomena. Probabilistic and wave propagation aspects are particularly studied. The electrogeometric model of lightning attraction to structures is used in combination with the log-normal probability distribution of lightning to ground currents. The log-normality is found to be retained for the currents collected by mast-type as well as line-type structures, but with a change of scale. For both types, exceedingly simple formulas for the number of hits are derived. Simple closed-form expressions for the line outage rates from back- flashovers and shielding failure flashovers are derived in a uniform way as functions of the critical currents. The expressions involve the standardized normal distribution function. System response is analysed by use of Laplace transforms in combination with text-book transmission-line theory. Inversion into time domain is accomplished by an approximate asymptotic method producing closed-form results. The back-flashover problem is analysed in particular. Approximate, image type expressions are derived for shunt admittance of wires above, on and under ground for analyses of fast transients. The derivation parallels that for series impedance, now well-known. 3 refs, 5 figs

PSPICE simulation of bipolar pulse converter based on short-circuited coaxial transmission line

International Nuclear Information System (INIS)

Shi Lei; Fan Yajun

2010-01-01

The operating principle of the bipolar pulse converter based on short-circuited coaxial transmission line type is given. The output bipolar pulses are simulated by using PSPICE program on condition of different electric length and different impedance of the short-circuited coaxial transmission line. The bipolar pulses are generated by using unipolar pulse with pulse width of 2 ns in experiment, the experimental result fit well with the simulation result. (authors)

Environmental impacts of power plants and transmission lines in power system planning

International Nuclear Information System (INIS)

Miracapillo, C.; Moreschini, G.; Rome Univ. 'La Sapienza'

1992-01-01

This paper deals with a criterion to assess the environmental impacts of power plants and transmission lines in power system planning. First, the effects of hydro-plants, thermal plants and transmission lines are reviewed. Then, a number of methods for the evaluation of the environmental impacts of civil and industrial plants are described. A new criterion is proposed to introduce the evaluation of the environmental impact and related costs into methods for power system planning. Finally, the criterion is applied to a simple case

Effect of a superconducting coil as a fault current limiter on current density distribution in BSCCO tape after an over-current pulse

International Nuclear Information System (INIS)

Tallouli, M; Yamaguchi, S.; Shyshkin, O.

2017-01-01

The development of power transmission lines based on long-length high temperature superconducting (HTS) tapes is complicated and technically challenging task. A serious problem for transmission line operation could become HTS power cable damage due to over-current pulse conditions. To avoid the cable damage in any urgent case the superconducting coil technology, i.e. superconductor fault current limiter (SFCL) is required. Comprehensive understanding of the current density characteristics of HTS tapes in both cases, either after pure over-current pulse or after over-current pulse limited by SFCL, is needed to restart or to continue the operation of the power transmission line. Moreover, current density distribution along and across the HTS tape provides us with the sufficient information about the quality of the tape performance in different current feeding regimes. In present paper we examine BSCCO HTS tape under two current feeding regimes. The first one is 100A feeding preceded by 900A over-current pulse. In this case none of tape protection was used. The second scenario is similar to the fist one but SFCL is used to limit an over-current value. For both scenarios after the pulse is gone and the current feeding is set up at 100A we scan magnetic field above the tape by means of Hall probe sensor. Then the feeding is turned of and the magnetic field scanning is repeated. Using the inverse problem numerical solver we calculate the corresponding direct and permanent current density distributions during the feeding and after switch off. It is demonstrated that in the absence of SFCL the current distribution is highly peaked at the tape center. At the same time the current distribution in the experiment with SFCL is similar to that observed under normal current feeding condition. The current peaking in the first case is explained by the effect of an opposite electric field induced at the tape edges during the overcurrent pulse decay, and by degradation of

Civilian applications for superconducting magnet technology developed for defense

International Nuclear Information System (INIS)

Johnson, R.A.; Klein, S.W.; Gurol, H.

1986-01-01

Seventy years after its discovery, superconducting technology is beginning to play an important role in the civilian sector. Strategic defense initiative (SDI)-related research in space- and ground-based strategic defense weapons, particularly research efforts utilizing superconducting magnet energy storage, magnetohydrodynamics (MHD), and superconducting pulsed-power devices, have direct applications in the civilian sector as well and are discussed in the paper. Other applications of superconducting magnets, which will be indirectly enhanced by the overall advancement in superconducting technology, include high-energy physics accelerators, magnetic resonance imaging, materials purifying, water purifying, superconducting generators, electric power transmission, magnetically levitated trains, magnetic-fusion power plants, and superconducting computers

Self-limiting current for magnetically insulated coaxial vacuum transmission lines

International Nuclear Information System (INIS)

Bergeron, K.D.

1976-11-01

Existing cold fluid theories for magnetic insulation are analyzed and applied to the transmission line configuration. The relevance of these results to the propagating short pulse problem, and to DC operation, are discussed

Efficient design of multituned transmission line NMR probes: the electrical engineering approach.

Science.gov (United States)

Frydel, J A; Krzystyniak, M; Pienkowski, D; Pietrzak, M; de Sousa Amadeu, N; Ratajczyk, T; Idzik, K; Gutmann, T; Tietze, D; Voigt, S; Fenn, A; Limbach, H H; Buntkowsky, G

2011-01-01

Transmission line-based multi-channel solid state NMR probes have many advantages regarding the cost of construction, number of RF-channels, and achievable RF-power levels. Nevertheless, these probes are only rarely employed in solid state-NMR-labs, mainly owing to the difficult experimental determination of the necessary RF-parameters. Here, the efficient design of multi-channel solid state MAS-NMR probes employing transmission line theory and modern techniques of electrical engineering is presented. As technical realization a five-channel ((1)H, (31)P, (13)C, (2)H and (15)N) probe for operation at 7 Tesla is described. This very cost efficient design goal is a multi port single coil transmission line probe based on the design developed by Schaefer and McKay. The electrical performance of the probe is determined by measuring of Scattering matrix parameters (S-parameters) in particular input/output ports. These parameters are compared to the calculated parameters of the design employing the S-matrix formalism. It is shown that the S-matrix formalism provides an excellent tool for examination of transmission line probes and thus the tool for a rational design of these probes. On the other hand, the resulting design provides excellent electrical performance. From a point of view of Nuclear Magnetic Resonance (NMR), calibration spectra of particular ports (channels) are of great importance. The estimation of the π/2 pulses length for all five NMR channels is presented. Copyright © 2011 Elsevier Inc. All rights reserved.

Design of the ITER Electron Cyclotron Heating and Current Drive Waveguide Transmission Line

Science.gov (United States)

Bigelow, T. S.; Rasmussen, D. A.; Shapiro, M. A.; Sirigiri, J. R.; Temkin, R. J.; Grunloh, H.; Koliner, J.

2007-11-01

The ITER ECH transmission line system is designed to deliver the power, from twenty-four 1 MW 170 GHz gyrotrons and three 1 MW 127.5 GHz gyrotrons, to the equatorial and upper launchers. The performance requirements, initial design of components and layout between the gyrotrons and the launchers is underway. Similar 63.5 mm ID corrugated waveguide systems have been built and installed on several fusion experiments; however, none have operated at the high frequency and long-pulse required for ITER. Prototype components are being tested at low power to estimate ohmic and mode conversion losses. In order to develop and qualify the ITER components prior to procurement of the full set of 24 transmission lines, a 170 GHz high power test of a complete prototype transmission line is planned. Testing of the transmission line at 1-2 MW can be performed with a modest power (˜0.5 MW) tube with a low loss (10-20%) resonant ring configuration. A 140 GHz long pulse, 400 kW gyrotron will be used in the initial tests and a 170 GHz gyrotron will be used when it becomes available. Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U.S. Dept. of Energy under contract DE-AC05-00OR22725.

The Transmission Line for the SPIDER experiment

International Nuclear Information System (INIS)

Boldrin, Marco; De Lorenzi, Antonio; Recchia, Mauro; Toigo, Vanni; Bonicelli, Tullio; Simon, Muriel

2011-01-01

The 100 keV Ion Source Test facility - Source for the Production of Ions of Deuterium Extracted from RF plasma (SPIDER) - is aimed to test the full scale prototype of the Ion Source for the ITER 1 MeV Neutral Beam Injector (NBI). The SPIDER facility requires the construction of a High Voltage Deck (HVD) and of a High Voltage Transmission Line (TL) respectively to host the Ion Source Power Supplies system polarized at 100 kV and to carry the power and signal conductors to the beam accelerator. In already existing NBI systems with beam energy above 100 keV, the TL is realized with the SF 6 Gas Insulated Line technology. In the SPIDER TL case, the presence of a large inner conductor (half meter diameter), would make the pressurized TL a complex and costly component; therefore a free air insulated solution has been proposed. The paper focuses on the design of this TL, which has to host inside the complex high potential (100 kV) inner electrode a number of power and measuring conductors and has to minimize the Electro Magnetic Interferences (EMI) produced by the frequent grids breakdowns. Finite Element (FE) analyses have been performed to verify the configuration from the electrostatic point of view, to evaluate EMI screening effectiveness and to assess the impact of the relatively high thermal dissipation of power conductors located inside the high potential electrode. Moreover, an experimental test campaign has been carried out on a TL mockup to validate the TL electrostatic configuration under DC voltage. Finally, the paper reports on the status of procurement activities for the Transmission Line.

New schemes for high-voltage pulsed generators based on stepped transmission lines

International Nuclear Information System (INIS)

Bossamykin, V.S.; Gordeev, V.S.; Pavlovskii, A.I.

1993-01-01

Wave processes were analyzed from the point of effective energy delivery in pulsed power systems based on transmission lines. A series of new schemes for the pulsed generators based on multistage stepped transmission lines both with the capacitive and inductive energy storage was found. These devices can provide voltage or current transformation up to 5-10 times due to wave processes if stage's characteristic impedances are in a certain correlation. The schemes suggested can be widely applied in the new powerful pulsed power accelerators. The theoretical conclusions are justified experimentally

Transmission line component testing for the ITER Ion Cyclotron Heating and Current Drive System

Science.gov (United States)

Goulding, Richard; Bell, G. L.; Deibele, C. E.; McCarthy, M. P.; Rasmussen, D. A.; Swain, D. W.; Barber, G. C.; Barbier, C. N.; Cambell, I. H.; Moon, R. L.; Pesavento, P. V.; Fredd, E.; Greenough, N.; Kung, C.

2014-10-01

High power RF testing is underway to evaluate transmission line components for the ITER Ion Cyclotron Heating and Current Drive System. The transmission line has a characteristic impedance Z0 = 50 Ω and a nominal outer diameter of 305 mm. It is specified to carry up to 6 MW at VSWR = 1.5 for 3600 s pulses, with transient voltages up to 40 kV. The transmission line is actively cooled, with turbulent gas flow (N2) used to transfer heat from the inner to outer conductor, which is water cooled. High voltage and high current testing of components has been performed using resonant lines generating steady state voltages of 35 kV and transient voltages up to 60 kV. A resonant ring, which has operated with circulating power of 6 MW for 1 hr pulses, is being used to test high power, low VSWR operation. Components tested to date include gas barriers, straight sections of various lengths, and 90 degree elbows. Designs tested include gas barriers fabricated from quartz and aluminum nitride, and transmission lines with quartz and alumina inner conductor supports. The latest results will be presented. This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy.

Effect of kicker circuit inductance on the transmission-line discharging

International Nuclear Information System (INIS)

Feng Deren; Wang Xiangqi; Shang Lei; Pei Yuanji; Fan Kuanjun

2004-01-01

Circuit inductance exists at discharging circuit of transmission-line, it includes the inductance at the main switch of thyratron when conducts, the linking inductance between the linking cables, the matching resistance inductance and the load inductance. When a long pulse is generated by transmission-line, the circuit inductance can be omitted. However, when the pulse is short (such as shorter than 200 ns), especially when ferromagnetic core kicker acts as the load, the effect is obvious. The short pulse current is needed in order to generate long time interval synchronous radiation light pulses by using online assembly of pulse convex orbit and DC convex orbit. This paper analyses the effect and presents several experimental results. It also supposes two practical cases to decrease the rise time of the pulse

Superconducting microstrip antennas: An experimental comparison of two feeding methods

International Nuclear Information System (INIS)

Richard, M.A.; Claspy, P.C.; Bhasin, K.B.

1993-01-01

The recent discovery of high-temperature superconductors (HTS's) has generated a substantial amount of interest in microstrip antenna applications. However, the high permittivity of substrates compatible with HTS causes difficulty in feeding such antennas because of the high patch edge impedance. In this paper, two methods for feeding HTS microstrip antennas at K and Ka-band are examined. Superconducting microstrip antennas that are directly coupled and gap-coupled to a microstrip transmission line have been designed and fabricated on lanthanum aluminate substrates using Y-Ba-Cu-O superconducting thin films. Measurements from these antennas, including input impedance, bandwidth, efficiency, and patterns, are presented and compared with published models. The measured results demonstrate that usable antennas can be constructed using either of these architectures, although the antennas suffer from narrow bandwidths. In each case, the HTS antenna shows a substantial improvement over an identical antenna made with normal metals

Electrical characteristics of long strings of SSC superconducting dipoles

International Nuclear Information System (INIS)

Shafer, R.E.; Smedley, K.M.

1992-01-01

Because long strings of series-connected superconducting magnets have no dc resistance and low ac losses, the string behaves like a shorted transmission line. The string is thus resonant at multiple half-wavelengths unless damped by the inclusion of resistors that couple to the LdI/dt voltage across the magnet inductance. Based on the measured ac characteristics of individual magnets, it is possible to predict the electrical properties of long strings of magnets for a variety of damping resistors. These strings can be simulated using an analytic representation in FORTRAN (using complex-number notation) or a discrete-component equivalent-circuit modelling program (e.g., SPICE). Various electrical parameters, including characteristic impedance, signal velocity, induced power-supply ripple current, attenuation lengths, and driving-point impedances, can be predicted, and the damping resistor value can be optimized. Comparisons will be made to measurements on a long string of superconducting Tevatron magnets, and some predictions will be made for the SSC collider magnet system

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)

Technical Challenges and Potential Solutions for Cross-Country Multi-Terminal Superconducting DC Power Cables

Science.gov (United States)

Al-Taie, A.; Graber, L.; Pamidi, S. V.

2017-12-01

Opportunities for applications of high temperature superconducting (HTS) DC power cables for long distance power transmission in increasing the reliability of the electric power grid and to enable easier integration of distributed renewable sources into the grid are discussed. The gaps in the technology developments both in the superconducting cable designs and cryogenic systems as well as power electronic devices are identified. Various technology components in multi-terminal high voltage DC power transmission networks and the available options are discussed. The potential of ongoing efforts in the development of superconducting DC transmission systems is discussed.

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

Superconduction in limiting-power synchronous generators. State, lines of development, problems

Energy Technology Data Exchange (ETDEWEB)

Lorenzen, H W; Sergl, J

1976-01-01

The limiting power of conventional 2-pole rotary current synchronous generators is estimated. The limiting power may be raised by using superconducting materials for the field winding. After a short description of superconductive materials, the construction of a synchronous generator with a superconducting field winding is described. Finally, some problems in calculating the magnetic field and the transient behavior are discussed.

Quantum heat engine with coupled superconducting resonators

DEFF Research Database (Denmark)

Hardal, Ali Ümit Cemal; Aslan, Nur; Wilson, C. M.

2017-01-01

the differences between the quantum and classical descriptions of our system by solving the quantum master equation and classical Langevin equations. Specifically, we calculate the mean number of excitations, second-order coherence, as well as the entropy, temperature, power, and mean energy to reveal......We propose a quantum heat engine composed of two superconducting transmission line resonators interacting with each other via an optomechanical-like coupling. One resonator is periodically excited by a thermal pump. The incoherently driven resonator induces coherent oscillations in the other one...... the signatures of quantum behavior in the statistical and thermodynamic properties of the system. We find evidence of a quantum enhancement in the power output of the engine at low temperatures....

The future of superconducting technology

International Nuclear Information System (INIS)

Kolm, H.H.

1974-01-01

As soon as cryogenic engineering problems are convincingly solved, superconducting technology is destined to play a vital role in mining, pollution control, medicine, power generation and transmission, and metallurgy. (author)

TEr azimuthal modes for a biconic transmission line in the small-gap limit

International Nuclear Information System (INIS)

Johnson, W.A.; Mendel, C.W. Jr.; Seidel, D.B.

1992-01-01

Azimuthally asymmetric modes in a biconic transmission line with a small-gap angle may be approximated by ''transmission-line-like'' modes. It is shown that the errors in these approximations are second order in the gap angle and approximate error bounds are provided. As an example demonstrating the application of this analysis in biconic structures, an analysis to characterize of the electromagnetic waves in the vacuum feed of the Particle Beam Fusion Accelerator II is provided

Improvement in operational characteristics of KEPCO’s line-commutation-type superconducting hybrid fault current limiter

Science.gov (United States)

Yim, S.-W.; Park, B.-C.; Jeong, Y.-T.; Kim, Y.-J.; Yang, S.-E.; Kim, W.-S.; Kim, H.-R.; Du, H.-I.

2013-01-01

A 22.9 kV class hybrid fault current limiter (FCL) developed by Korea Electric Power Corporation and LS Industrial Systems in 2006 operates using the line commutation mechanism and begins to limit the fault current after the first half-cycle. The first peak of the fault current is available for protective coordination in the power system. However, it also produces a large electromagnetic force and imposes a huge stress on power facilities such as the main transformer and gas-insulated switchgear. In this study, we improved the operational characteristics of the hybrid FCL in order to reduce the first peak of the fault current. While maintaining the structure of the hybrid FCL system, we developed a superconducting module that detects and limits the fault current during the first half-cycle. To maintain the protective coordination capacity, the hybrid FCL was designed to reduce the first peak value of the fault current by up to approximately 30%. The superconducting module was also designed to produce a minimum AC loss, generating a small, uniform magnetic field distribution during normal operation. Performance tests confirmed that when applied to the hybrid FCL, the superconducting module showed successful current limiting operation without any damage.

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

Study of thermal response of superconducting NbN meander line by using 20 ps pulse laser

International Nuclear Information System (INIS)

Miki, Shigehito; Fujiwara, Daisuke; Simakage, Hisashi; Kawakami, Akira; Wang Zhen; Satoh, Kazuo; Yotsuya, Tsutomu; Ishida, Takekazu

2005-01-01

The thermal response of a superconducting NbN thin-film meander line was studied by irradiating with a 20 ps pulse laser. A 10 nm-thick NbN thin film was prepared by dc magnetron sputtering and then processed to fabricate a 3 μm-wide, 125.5 mm-long meander line. The device was placed in a 4 K refrigerator, and the bias temperature was kept below the critical temperature T c . The end of an optical fiber was fixed at the front of a meander line, which was then directly irradiated by using the 20 ps pulse laser. The output voltage was observed with a digital oscilloscope and a low-noise amplifier. The output signals of the thermal response were clearly observed

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

International Nuclear Information System (INIS)

Naqui, J.; Su, L.; Mata, J.; Martín, F.

2015-01-01

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

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...

Losses at magnetic nulls in pulsed-power transmission line systems

International Nuclear Information System (INIS)

Mendel, C.W. Jr.; Pointon, T.D.; Savage, M.E.; Seidel, D.B.; Magne, I.; Vezinet, R.

2006-01-01

Pulsed-power systems operating in the terawatt regime must deal with large electron flows in vacuum transmission lines. In most parts of these transmission lines the electrons are constrained by the self-magnetic field to flow parallel to the conductors. In very low impedance systems, such as those used to drive Z-pinch radiation sources, the currents from multiple transmission lines are added together. This addition necessarily involves magnetic nulls that connect the positive and negative electrodes. The resultant local loss of magnetic insulation results in electron losses at the anode in the vicinity of the nulls. The lost current due to the magnetic null might or might not be appreciable. In some cases the lost current due to the null is not large, but is spatially localized, and may create a gas and plasma release from the anode that can lead to an excessive loss, and possibly to catastrophic damage to the hardware. In this paper we describe an analytic model that uses one geometric parameter (aside from straightforward hardware size measurements) that determines the loss to the anode, and the extent of the loss region when the driving source and load are known. The parameter can be calculated in terms of the magnetic field in the region of the null calculated when no electron flow is present. The model is compared to some experimental data, and to simulations of several different hardware geometries, including some cases with multiple nulls, and unbalanced feeds

Superconducting materials for large scale applications

International Nuclear Information System (INIS)

Scanlan, Ronald M.; Malozemoff, Alexis P.; Larbalestier, David C.

2004-01-01

Significant improvements in the properties of superconducting materials have occurred recently. These improvements are being incorporated into the latest generation of wires, cables, and tapes that are being used in a broad range of prototype devices. These devices include new, high field accelerator and NMR magnets, magnets for fusion power experiments, motors, generators, and power transmission lines. These prototype magnets are joining a wide array of existing applications that utilize the unique capabilities of superconducting magnets:accelerators such as the Large Hadron Collider, fusion experiments such as ITER, 930 MHz NMR, and 4 Tesla MRI. In addition, promising new materials such as MgB2 have been discovered and are being studied in order to assess their potential for new applications. In this paper, we will review the key developments that are leading to these new applications for superconducting materials. In some cases, the key factor is improved understanding or development of materials with significantly improved properties. An example of the former is the development of Nb3Sn for use in high field magnets for accelerators. In other cases, the development is being driven by the application. The aggressive effort to develop HTS tapes is being driven primarily by the need for materials that can operate at temperatures of 50 K and higher. The implications of these two drivers for further developments will be discussed. Finally, we will discuss the areas where further improvements are needed in order for new applications to be realized

Development of an accurate transmission line fault locator using the global positioning system satellites

Science.gov (United States)

Lee, Harry

1994-01-01

A highly accurate transmission line fault locator based on the traveling-wave principle was developed and successfully operated within B.C. Hydro. A transmission line fault produces a fast-risetime traveling wave at the fault point which propagates along the transmission line. This fault locator system consists of traveling wave detectors located at key substations which detect and time tag the leading edge of the fault-generated traveling wave as if passes through. A master station gathers the time-tagged information from the remote detectors and determines the location of the fault. Precise time is a key element to the success of this system. This fault locator system derives its timing from the Global Positioning System (GPS) satellites. System tests confirmed the accuracy of locating faults to within the design objective of +/-300 meters.

On the Transmission Line Pulse Measurement Technique

OpenAIRE

X. Rodriguez; M. Eduardo; M. Harington

2015-01-01

Transmission Line Pulse is a short pulse (25ns to 150ns) measurement of the current-voltage (I/V) characteristics of the ESD protection built into an integrated circuit. The short TLP pulses are used to simulate the short ESD pulse threats and integrated circuit must tolerate without being damaged. In this work the fundamental principles of how the TLP pulse is generated and used to create I-V characteristic plots will be explored. The measurement will be then used to characterize the I-V cha...

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.

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

OpenAIRE

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

2018-01-01

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-en...

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.

Comparison of Transmission Line Methods for Surface Acoustic Wave Modeling

Science.gov (United States)

Wilson, William; Atkinson, Gary

2009-01-01

Surface Acoustic Wave (SAW) technology is low cost, rugged, lightweight, extremely low power and can be used to develop passive wireless sensors. For these reasons, NASA is investigating the use of SAW technology for Integrated Vehicle Health Monitoring (IVHM) of aerospace structures. To facilitate rapid prototyping of passive SAW sensors for aerospace applications, SAW models have been developed. This paper reports on the comparison of three methods of modeling SAWs. The three models are the Impulse Response Method (a first order model), and two second order matrix methods; the conventional matrix approach, and a modified matrix approach that is extended to include internal finger reflections. The second order models are based upon matrices that were originally developed for analyzing microwave circuits using transmission line theory. Results from the models are presented with measured data from devices. Keywords: Surface Acoustic Wave, SAW, transmission line models, Impulse Response Method.

The 12th 735-kV transmission line project: Hydro-Quebec network

International Nuclear Information System (INIS)

1992-01-01

Hydro-Quebec is proposing to construct a 735-kV transmission line from the Chissibi station near the LG3 hydroelectric power plant to the Jacques-Cartier station near Quebec City. The width of the right-of-way will generally be 90 m and it is intended to install the line in two stages. The Chissibi-Chibougamau section should enter service in 1993 and the Chibougamau-Cartier section in 1994. The cost of the line is estimated at $1.21 billion, of which $900 million is for line construction and $310 million for station equipment. Prospective corridors for the line route have been selected, portions of which enable twinning with Hydro-Quebec's existing 9th 735-kV line. A series of hearings on the environmental and other impacts of the power line project was held by the Bureau d'audiences publiques sur l'environnement and results are summarized along with the views of the Bureau. The summary describes the justification for the project, the choice of the transmission line route, the evaluation of the impacts of the project on the natural and human environments, health effects due to magnetic fields, and effects on the economic development of northern Quebec. Recommendations are given for mitigating the impacts of the project. 13 refs., 8 figs., 2 tabs

Vertical Line Nodes in the Superconducting Gap Structure of Sr_{2}RuO_{4}

Directory of Open Access Journals (Sweden)

E. Hassinger

2017-03-01

Full Text Available There is strong experimental evidence that the superconductor Sr_{2}RuO_{4} has a chiral p-wave order parameter. This symmetry does not require that the associated gap has nodes, yet specific heat, ultrasound, and thermal conductivity measurements indicate the presence of nodes in the superconducting gap structure of Sr_{2}RuO_{4}. Theoretical scenarios have been proposed to account for the existence of deep minima or accidental nodes (minima tuned to zero or below by material parameters within a p-wave state. Other scenarios propose chiral d-wave and f-wave states, with horizontal and vertical line nodes, respectively. To elucidate the nodal structure of the gap, it is essential to know whether the lines of nodes (or minima are vertical (parallel to the tetragonal c axis or horizontal (perpendicular to the c axis. Here, we report thermal conductivity measurements on single crystals of Sr_{2}RuO_{4} down to 50 mK for currents parallel and perpendicular to the c axis. We find that there is substantial quasiparticle transport in the T=0 limit for both current directions. A magnetic field H immediately excites quasiparticles with velocities both in the basal plane and in the c direction. Our data down to T_{c}/30 and down to H_{c2}/100 show no evidence that the nodes are in fact deep minima. Relative to the normal state, the thermal conductivity of the superconducting state is found to be very similar for the two current directions, from H=0 to H=H_{c2}. These findings show that the gap structure of Sr_{2}RuO_{4} consists of vertical line nodes. This rules out a chiral d-wave state. Given that the c-axis dispersion (warping of the Fermi surface in Sr_{2}RuO_{4} varies strongly from sheet to sheet, the small a-c anisotropy suggests that the line nodes are present on all three sheets of the Fermi surface. If imposed by symmetry, vertical line nodes would be inconsistent with a p-wave order parameter for Sr_{2}RuO_{4}. To reconcile the gap structure

600 GHz resonant mode in a parallel array of Josephson tunnel junctions connected by superconducting microstrip lines

DEFF Research Database (Denmark)

Kaplunenko, V. K.; Larsen, Britt Hvolbæk; Mygind, Jesper

1994-01-01

on experimental and numerical investigations of a resonant step observed at a voltage corresponding to 600 GHz in the dc current-voltage characteristic of a parallel array of 20 identical small NbAl2O3Nb Josephson junctions interconnected by short sections of superconducting microstrip line. The junctions...... are mutually phase locked due to collective interaction with the line sections excited close to the half wavelength resonance. The phase locking range can be adjusted by means of an external dc magnetic field and the step size varies periodically with the magnetic field. The largest step corresponds...

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

2018-02-01

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.

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)

Superconducting Switch for Fast On-Chip Routing of Quantum Microwave Fields

Science.gov (United States)

Pechal, M.; Besse, J.-C.; Mondal, M.; Oppliger, M.; Gasparinetti, S.; Wallraff, A.

2016-08-01

A switch capable of routing microwave signals at cryogenic temperatures is a desirable component for state-of-the-art experiments in many fields of applied physics, including but not limited to quantum-information processing, communication, and basic research in engineered quantum systems. Conventional mechanical switches provide low insertion loss but disturb operation of dilution cryostats and the associated experiments by heat dissipation. Switches based on semiconductors or microelectromechanical systems have a lower thermal budget but are not readily integrated with current superconducting circuits. Here we design and test an on-chip switch built by combining tunable transmission-line resonators with microwave beam splitters. The device is superconducting and as such dissipates a negligible amount of heat. It is compatible with current superconducting circuit fabrication techniques, operates with a bandwidth exceeding 100 MHz, is capable of handling photon fluxes on the order of 1 05 μ s-1 , equivalent to powers exceeding -90 dBm , and can be switched within approximately 6-8 ns. We successfully demonstrate operation of the device in the quantum regime by integrating it on a chip with a single-photon source and using it to route nonclassical itinerant microwave fields at the single-photon level.

Experimental study of the Fermi–Pasta–Ulam recurrence in a bi-modal electrical transmission line

International Nuclear Information System (INIS)

Farota, Abdou K; Faye, Mansour M

2013-01-01

We report on the experimental observation of the Fermi–Pasta–Ulam (FPU) recurrence in an experimental bi-modal nonlinear transmission line. The FPU recurrence is observed in the two transmission modes known as the low frequency mode and the high frequency mode. In each case, a spectrum analysis is performed in order to study the waves along the line. (paper)

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

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

Directory of Open Access Journals (Sweden)

B. T. Hutsel

2018-03-01

Full Text Available 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

Transient characteristics of parallel running of the 20kVA superconducting synchronous generator and a conventional one

International Nuclear Information System (INIS)

Nitta, T.; Okada, T.

1989-01-01

This paper describes electrical transient characteristics of parallel running of the 20kVA superconducting synchronous generator and a conventional one. In the experimental power system, the superconducting generator is connected through reactors (artificial transmission lines) to a regional power system (infinite bus) and the conventional generator (20kVA) is connected to the terminal of the superconducting generator. Several tests were performed in order to consider the transient behavior of superconducting generator (SCG) in the power system. The items of the tests are synchronous closing test, loss of synchronism test and disconnecting and reclosing test. From the experimental results, it can be said that by installing SCG in power systems, voltage stability and power system stability can be improved in transient states as well as in steady states and the variation of armature current of SCG during a transient period is extremely larger than that of the conventional one. The transient analysis by a computer simulation was also carried out for the experiments. The simulation results are in good agreement with the experimental ones

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 ...

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.

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.

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.

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)

Superconductivity applications for infrared and microwave devices II; Proceedings of the Meeting, Orlando, FL, Apr. 4, 5, 1991

Science.gov (United States)

Heinen, Vernon O.; Bhasin, Kul B.

Topics discussed include thin-film technology, microwave transmission lines and resonators, microwave devices and circuits, infrared detectors and bolometers, and superconducting junctions. Papers are presented on possible enhancement in bolometric response using free-standing film of YBa2Cu3O(x), aging and surface instability in high-Tc superconductors, epitaxial Tl2Ba2CaCu2O8 thin films on LaAlO3 and their microwave device properties, the performance of stripline resonators using sputtered YBCO films, and a coplanar waveguide microwave filter of YBa2Cu3O7. Attention is also given to the performance characteristics of Y-Ba-Cu-O microwave superconducting detectors, high-Tc bolometer developments for planetary missions, infrared detectors from YBaCuO thin films, high-temperature superconductor junction technology, and submillimeter receiver components using superconducting tunnel junctions. (For individual items see A93-27244 to A93-27248)

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.

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.

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.

Two-gap superconductivity with line nodes in CsCa2Fe4As4F2

Science.gov (United States)

Kirschner, Franziska K. K.; Adroja, Devashibhai T.; Wang, Zhi-Cheng; Lang, Franz; Smidman, Michael; Baker, Peter J.; Cao, Guang-Han; Blundell, Stephen J.

2018-02-01

We report the results of a muon-spin rotation (μ SR ) experiment to determine the superconducting ground state of the iron-based superconductor CsCa2Fe4As4F2 with Tc≈28.3 K . This compound is related to the fully gapped superconductor CaCsFe4As4 , but here the Ca-containing spacer layer is replaced with one containing Ca2F2 . The temperature evolution of the penetration depth strongly suggests the presence of line nodes and is best modeled by a system consisting of both an s - and a d -wave gap. We also find a potentially magnetic phase which appears below ≈10 K but does not appear to compete with the superconductivity. This compound contains the largest alkali atom in this family of superconductors, and our results yield a value for the in-plane penetration depth of λa b(T =0 ) =244 (3 ) nm .

Growth and applications of superconducting Y-Ba-Cu-O thin films

International Nuclear Information System (INIS)

Pinto, R.

1991-01-01

This paper attempt to highlight the important PVD techniques such as evaporation, sputtering, ion beam deposition and excimer laser ablation for the preparation of superconducting YBaCuO thin films. Since enormous amount of work has been published over the last few years, this review is not comprehensive even in PVD techniques. In the area of applications for electronics, thin film appear to be much more promising than bulk high T c superconductors. Already high J c values in the region of 4 x 10 6 A cm -2 have been realized in thin films. Resonators and transmission lines have been fabricated using 123 films showing a transmission loss significantly lower than that of copper at 77 degrees K at X-band frequencies. This review will discuss some of the important electronic applications feasible with 123 films

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.

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.

Superconducting magnetic energy storage

International Nuclear Information System (INIS)

Rogers, J.D.; Boenig, H.J.

1978-01-01

Superconducting inductors provide a compact and efficient means of storing electrical energy without an intermediate conversion process. Energy storage inductors are under development for diurnal load leveling and transmission line stabilization in electric utility systems and for driving magnetic confinement and plasma heating coils in fusion energy systems. Fluctuating electric power demands force the electric utility industry to have more installed generating capacity than the average load requires. Energy storage can increase the utilization of base-load fossil and nuclear power plants for electric utilities. Superconducting magnetic energy storage (SMES) systems, which will store and deliver electrical energy for load leveling, peak shaving, and the stabilization of electric utility networks are being developed. In the fusion area, inductive energy transfer and storage is also being developed by LASL. Both 1-ms fast-discharge theta-pinch and 1-to-2-s slow tokamak energy transfer systems have been demonstrated. The major components and the method of operation of an SMES unit are described, and potential applications of different size SMES systems in electric power grids are presented. Results are given for a 1-GWh reference design load-leveling unit, for a 30-MJ coil proposed stabilization unit, and for tests with a small-scale, 100-kJ magnetic energy storage system. The results of the fusion energy storage and transfer tests are also presented. The common technology base for the systems is discussed

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

Environmental Assessment and Finding of No Significant Impact: Curecanti-Lost Canyon 230-kV Transmission Line Reroute Project, Montrose County, Colorado

Energy Technology Data Exchange (ETDEWEB)

N/A

2000-03-20

The Department of Energy (DOE), Western Area Power Administration (Western) is proposing to reroute a section of the Curecanti-Lost Canyon 230-kilovolt (kV) transmission line, in Montrose County, Colorado. A portion of the transmission line, situated 11 miles southeast of Montrose, Colorado, crosses Waterdog Peak, an area of significant geologic surface activity, which is causing the transmission line's lattice steel towers to shift. This increases stress to structure hardware and conductors, and poses a threat to the integrity of the transmission system. Western proposes to relocate the lattice steel towers and line to a more geologically stable area. The existing section of transmission line and the proposed relocation route cross Bureau of Land Management and private land holdings.

Broadband microwave frequency doubler based on left-handed nonlinear transmission lines

International Nuclear Information System (INIS)

Huang Jie; Gu Wenwen; Zhao Qian

2017-01-01

A bandwidth microwave second harmonic generator is successfully designed using composite right/left-handed nonlinear transmission lines (CRLH NLTLs) in a GaAs monolithic microwave integrated circuit (MMIC) technology. The structure parameters of CRLH NLTLs, e.g. host transmission line, rectangular spiral inductor, and nonlinear capacitor, have a great impact on the second harmonic performance enhancement in terms of second harmonic frequency, output power, and conversion efficiency. It has been experimentally demonstrated that the second harmonic frequency is determined by the anomalous dispersion of CRLH NLTLs and can be significantly improved by effectively adjusting these structure parameters. A good agreement between the measured and simulated second harmonic performances of Ka-band CRLH NLTLs frequency multipliers is successfully achieved, which further validates the design approach of frequency multipliers on CRLH NLTLs and indicates the potentials of CRLH NLTLs in terms of the generation of microwave and millimeter-wave signal source. (paper)

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)

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

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.

Co-sputtered Mo/Re superconducting coplanar resonators compatible with carbon nanotube growth

Energy Technology Data Exchange (ETDEWEB)

Blien, Stefan; Stiller, Peter L.; Goetz, Karl; Vavra, Ondrej; Huber, Thomas; Mayer, Thomas; Strunk, Christoph; Huettel, Andreas K. [Institute for Experimental and Applied Physics, University of Regensburg, 93040 Regensburg (Germany)

2016-07-01

Carbon nanotubes are simultaneously prototypical single electron tunneling devices and nano-electromechanical resonators. In particular for ''ultraclean'' devices, where the nanotube is grown in a last fabrication step over pre-existing chip structures, highly regular quantum spectra and high mechanical quality factors emerge. Targeting optomechanical experiments, a coupling of these devices to on-chip superconducting coplanar waveguide resonators is highly desirable. The conditions for in-situ growth of carbon nanotubes over metal contacts are quite detrimental to most superconductors: the CVD growth process takes place in a hydrogen/methane atmosphere heated up to 900 {sup circle} C. We present data on transmission line resonators fabricated of a co-sputtered molybdenum rhenium alloy that withstand CVD and remain superconducting with critical temperatures up to 8K after growth. Resonant operation at cryogenic temperatures is demonstrated, and the behaviour is highly consistent with a combination of Mattis-Bardeen theory and two-level systems in the substrate.

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.

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...

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...

Realization of superconductive films by screen printing

International Nuclear Information System (INIS)

Baudry, H.

1988-01-01

Screen printing is a promising method to manufacture superconductive lines making use of superconductive ceramics. An ink has been realized with YBa 2 Cu 3 0 7-x' and the process conditions defined by thermal analysis. A superconductive transition is observed after screen printing on MgO. The firing of the layer is made at 920 0 C followed by a reoxidation step at 420 0 C. The silver electrical contacts are also screen printed [fr

Superconductivity in a copper(II)-based coordination polymer with perfect kagome structure

Energy Technology Data Exchange (ETDEWEB)

Huang, Xing; Liu, Liyao; Xu, Wei; Zhu, Daoben [Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing (China); University of Chinese Academy of Sciences, Beijing (China); Zhang, Shuai [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing (China); Yu, Lei [Department of Chemistry, University of Kentucky, Lexington, KY (United States); Chen, Genfu [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing (China); University of Chinese Academy of Sciences, Beijing (China); Collaborative Innovation Center of Quantum Matter, Beijing (China)

2018-01-02

A highly crystalline copper(II) benzenehexathiolate coordination polymer (Cu-BHT) has been prepared. The two-dimensional kagome structure has been confirmed by powder X-ray diffraction, high-resolution transmission electron microscopy, and high-resolution scanning transmission electron microscopy. The as-prepared sample exhibits bulk superconductivity at about 0.25 K, which is confirmed by the zero resistivity, AC magnetic susceptibility, and specific heat measurements. Another diamagnetic transition at about 3 K suggests that there is a second superconducting phase that may be associated with a single layer or few layers of Cu-BHT. It is the first time that superconductivity has been observed in a coordination polymer. (copyright 2018 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

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.

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.

Using technique vibration diagnostics for assessing the quality of power transmission line supports repairs

Directory of Open Access Journals (Sweden)

Cherpakov Aleksander

2017-01-01

Full Text Available The considered method for assessing the quality of the repair work to restore the rack supports of transmission lines is based on the method of vibration diagnostics. Power transmission line supports with a symmetrical destruction of the protective layer of concrete in the ground in violation of the construction section were chosen as an object. Finite element modelling package Ansys was used in assessing the quality of repair work. The example of evaluating the quality of repair using the relative adhesion defective area design criteria in the analysis of natural vibration frequencies is given.

Superconducting linac booster

International Nuclear Information System (INIS)

Srinivasan, B.; Betigeri, M.G.; Pandey, M.K.; Pillay, R.G.; Kurup, M.B.

1997-01-01

The report on superconducting LINAC booster, which is a joint project of Bhabha Atomic Research Centre (BARC) and Tata Institute of Fundamental Research (TIFR), brings out the work accomplished so far towards the development of the technology of superconducting LINAC to boost the energy of ions from the 14UD Pelletron. The LINAC is modular in construction with each module comprising of a helium cryostat housing four lead-plated quarter wave resonators. The resonators are superconducting for temperatures below 7.19K. An energy boost of 2 MeV/q per module is expected to be achieved. The first module and the post-tandem superbuncher have been fabricated and tested on the LINAC beam line. This report gives a summary of the technological achievements and also brings out the difficulties encountered during the R and D phase. (author)

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

DEFF Research Database (Denmark)

Stadler, Robert; Markussen, Troels

2011-01-01

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 hav...... calculations for a variety of t-stub molecules and also address their suitability for thermoelectric applications....

Acoustic wave spread in superconducting-normal-superconducting sandwich

International Nuclear Information System (INIS)

Urushadze, G.I.

2004-01-01

The acoustic wave spread, perpendicular to the boundaries between superconducting and normal metals in superconducting-normal-superconducting (SNS) sandwich has been considered. The alternate current flow sound induced by the Green function method has been found and the coefficient of the acoustic wave transmission through the junction γ=(S 1 -S 2 )/S 1 , (where S 1 and S 2 are average energy flows formed on the first and second boundaries) as a function of the phase difference between superconductors has been investigated. It is shown that while the SNS sandwich is almost transparent for acoustic waves (γ 0 /τ), n=0,1,2, ... (where τ 0 /τ is the ratio of the broadening of the quasiparticle energy levels in impurity normal metal as a result of scattering of the carriers by impurities 1/τ to the spacing between energy levels 1/τ 0 ), γ=2, (S 2 =-S 1 ), which corresponds to the full reflection of the acoustic wave from SNS sandwich. This result is valid for the limit of a pure normal metal but in the main impurity case there are two amplification and reflection regions for acoustic waves. The result obtained shows promise for the SNS sandwich as an ideal mirror for acoustic wave reflection

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)

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.

Superconducting classes in heavy fermions systems

International Nuclear Information System (INIS)

Volovik, G.E.; Gor'kov, L.P.

1985-01-01

A mathematical method for constructing of the superconductivity classes for nontrivial superconductors is described. All superconducting phases which can arise directly on transition from the normal state for cubic, hexagonal and tetragonal symmetries are enumerated. It is shown that in the triplet case the types of zeros in the energy gap always correspond to points on the Fermi surface, whereas for signlet pairing the whole zero lines are possible. For the phases with zeros on the lines or points, the low-temperature specific heat varies as T 2 on T 3 respectivelty. The superconducting phases which arise from the multydimensional representations may possess a magnetic moment which induces currents on the surface of a monodomain sample even in the absence of an external magnetic field. The specific case of a domain wall is considered and it is shown that large magnetic currents of magnetization are present in the wall

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...

The superconducting bending magnets 'CESAR'

CERN Document Server

Pérot, J

1978-01-01

In 1975, CERN decided to build two high precision superconducting dipoles for a beam line in the SPS north experimental area. The aim was to determine whether superconducting magnets of the required accuracy and reliability can be built and what their economies and performances in operation will be. Collaboration between CERN and CAE /SACLAY was established in order to make use of the knowledge and experience already acquired in the two laboratories. (0 refs).

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.

Superconducting kinetic inductance detectors for astrophysics

International Nuclear Information System (INIS)

Vardulakis, G; Withington, S; Goldie, D J; Glowacka, D M

2008-01-01

The kinetic inductance detector (KID) is an exciting new device that promises high-sensitivity, large-format, submillimetre to x-ray imaging arrays for astrophysics. KIDs comprise a superconducting thin-film microwave resonator capacitively coupled to a probe transmission line. By exciting the electrical resonance with a microwave probe signal, the transmission phase of the resonator can be monitored, allowing the deposition of energy or power to be detected. We describe the fabrication and low-temperature testing, down to 26 mK, of a number of devices, and confirm the basic principles of operation. The KIDs were fabricated on r-plane sapphire using superconducting niobium and aluminium as the resonator material, and tantalum as the x-ray absorber. KID quality factors of up to Q = (741 ± 15) × 10 3 were measured for niobium at 1 K, and quasiparticle effective recombination times of τ* R = 30 µs after x-ray absorption. Al/Ta quasiparticle traps were combined with resonators to make complete detectors. These devices were operated at 26 mK with quality factors of up Q = (187.7 ± 3.5) × 10 3 and a phase-shift responsivity of ∂θ/∂N qp = (5.06 ± 0.23) × 10 −6 degrees per quasiparticle. Devices were characterized both at thermal equilibrium and as x-ray detectors. A range of different x-ray pulse types was observed. Low phase-noise readout measurements on Al/Ta KIDs gave a minimum NEP = 1.27 × 10 −16 W Hz −1/2 at a readout frequency of 550 Hz and NEP = 4.60 × 10 −17 W Hz −1/2 at 95 Hz, for effective recombination times τ* R = 100 µs and τ* R = 350 µs respectively. This work demonstrates that high-sensitivity detectors are possible, encouraging further development and research into KIDs

Study of a phase-to-ground fault on a 400 kV overhead transmission line

Science.gov (United States)

Iagăr, A.; Popa, G. N.; Diniş, C. M.

2018-01-01

Power utilities need to supply their consumers at high power quality level. Because the faults that occur on High-Voltage and Extra-High-Voltage transmission lines can cause serious damages in underlying transmission and distribution systems, it is important to examine each fault in detail. In this work we studied a phase-to-ground fault (on phase 1) of 400 kV overhead transmission line Mintia-Arad. Indactic® 650 fault analyzing system was used to record the history of the fault. Signals (analog and digital) recorded by Indactic® 650 were visualized and analyzed by Focus program. Summary of fault report allowed evaluation of behavior of control and protection equipment and determination of cause and location of the fault.

The interplay of superconducting quantum circuits and propagating microwave states

International Nuclear Information System (INIS)

Goetz, Jan

2017-01-01

Superconducting circuit quantum electrodynamics (QED) has developed into a powerful platform for studying the interaction between matter and different states of light. In this context, superconducting quantum bits (qubits) act as artificial atoms interacting with quantized modes of the electromagnetic field. The field can be trapped in superconducting microwave resonators or propagating in transmission lines. In this thesis, we particularly study circuit QED systems where microwave fields are coupled with superconducting flux and transmon qubits. We optimize the coherence properties of the resonators, by analyzing loss mechanisms at excitation powers of approximately one photon on average. We find that two-level fluctuators associated with oxide layers at substrate and metal surfaces and metal-metal interfaces represent the predominant loss channel. Furthermore, we show how broadband thermal photon fields influence the relaxation and dephasing properties of a superconducting transmon qubit. To this end, we study several second-order loss channels of the transmon qubit and find that the broadband fields introduce a larger decay rate than expected from the Purcell filter defined by the resonator. Additionally, we show that qubit dephasing at the flux-insensitive point as well as low-frequency parameter fluctuations can be enhanced by thermal fields. Finally, we study how artificial atoms react to changes in inherent properties of the light fields. We perform a detailed analysis of the photon statistics of thermal fields using their relation to the qubits coherence properties. We quantitatively recover the expected n 2 + n-law for the photon number variance and confirm this result by direct correlation measurements. We then show a novel technique for the in-situ conversion of the interaction parity in light-matter interaction. To this end, we couple spatially controlled microwave fields to a flux qubit with two degrees of freedom.

The interplay of superconducting quantum circuits and propagating microwave states

Energy Technology Data Exchange (ETDEWEB)

Goetz, Jan

2017-06-26

Superconducting circuit quantum electrodynamics (QED) has developed into a powerful platform for studying the interaction between matter and different states of light. In this context, superconducting quantum bits (qubits) act as artificial atoms interacting with quantized modes of the electromagnetic field. The field can be trapped in superconducting microwave resonators or propagating in transmission lines. In this thesis, we particularly study circuit QED systems where microwave fields are coupled with superconducting flux and transmon qubits. We optimize the coherence properties of the resonators, by analyzing loss mechanisms at excitation powers of approximately one photon on average. We find that two-level fluctuators associated with oxide layers at substrate and metal surfaces and metal-metal interfaces represent the predominant loss channel. Furthermore, we show how broadband thermal photon fields influence the relaxation and dephasing properties of a superconducting transmon qubit. To this end, we study several second-order loss channels of the transmon qubit and find that the broadband fields introduce a larger decay rate than expected from the Purcell filter defined by the resonator. Additionally, we show that qubit dephasing at the flux-insensitive point as well as low-frequency parameter fluctuations can be enhanced by thermal fields. Finally, we study how artificial atoms react to changes in inherent properties of the light fields. We perform a detailed analysis of the photon statistics of thermal fields using their relation to the qubits coherence properties. We quantitatively recover the expected n{sup 2} + n-law for the photon number variance and confirm this result by direct correlation measurements. We then show a novel technique for the in-situ conversion of the interaction parity in light-matter interaction. To this end, we couple spatially controlled microwave fields to a flux qubit with two degrees of freedom.

Superconducting materials for large scale applications

Energy Technology Data Exchange (ETDEWEB)

Scanlan, Ronald M.; Malozemoff, Alexis P.; Larbalestier, David C.

2004-05-06

Significant improvements in the properties ofsuperconducting materials have occurred recently. These improvements arebeing incorporated into the latest generation of wires, cables, and tapesthat are being used in a broad range of prototype devices. These devicesinclude new, high field accelerator and NMR magnets, magnets for fusionpower experiments, motors, generators, and power transmission lines.These prototype magnets are joining a wide array of existing applicationsthat utilize the unique capabilities of superconducting magnets:accelerators such as the Large Hadron Collider, fusion experiments suchas ITER, 930 MHz NMR, and 4 Tesla MRI. In addition, promising newmaterials such as MgB2 have been discovered and are being studied inorder to assess their potential for new applications. In this paper, wewill review the key developments that are leading to these newapplications for superconducting materials. In some cases, the key factoris improved understanding or development of materials with significantlyimproved properties. An example of the former is the development of Nb3Snfor use in high field magnets for accelerators. In other cases, thedevelopment is being driven by the application. The aggressive effort todevelop HTS tapes is being driven primarily by the need for materialsthat can operate at temperatures of 50 K and higher. The implications ofthese two drivers for further developments will be discussed. Finally, wewill discuss the areas where further improvements are needed in order fornew applications to be realized.

Flux flow, pinning, and resistive behavior in superconducting networks

International Nuclear Information System (INIS)

Teitel, S.

1991-10-01

We have studied the behavior of fluctuation effects in superconducting systems using numerical simulations of XY and Coulomb gas models. Flux flow resistance in two dimensional Josephson junction arrays has been calculated, and related to correlations in vortex structure. Randomness has been introduced, and its effects on the superconducting transition, and vortex mobility, have been studied. We find that randomness destroys phase coherence, yet the randomness induced pinning reduces flux flow resistance at low temperatures. Vortex line fluctuations in high temperature superconductors have been studied using a three dimensional XY model. We have considered the melting of the vortex line lattice, and the entanglement and cutting of vortex lines in the vortex line liquid phase. Vortex line entangling and cutting appear to occur on the same length scales in the liquid phase. The vortex structure function has been calculated and from it, elastic properties of the vortex line liquid have been inferred. The two dimensional classical Coulomb gas, where charges map onto vortices in the superconducting system, has been simulated. The melting transitions of ordered charge (vortex) lattices have been studied, and we find evidence that these transitions do not have the critical behavior expected from standard symmetry analysis

Far-infrared transmission of a superconducting NbN film

Czech Academy of Sciences Publication Activity Database

Šindler, M.; Tesař, Roman; Koláček, Jan; Skrbek, L.; Šimša, Zdeněk

2010-01-01

Roč. 81, č. 18 (2010), 184529/1-184529/5 ISSN 1098-0121 R&D Projects: GA ČR GA202/08/0326 Institutional research plan: CEZ:AV0Z10100521 Keywords : superconductivity * BCS theory * terahertz radiation Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.772, year: 2010

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)

The top-transmon: a hybrid superconducting qubit for parity-protected quantum computation

International Nuclear Information System (INIS)

Hassler, F; Akhmerov, A R; Beenakker, C W J

2011-01-01

Qubits constructed from uncoupled Majorana fermions are protected from decoherence, but to perform a quantum computation this topological protection needs to be broken. Parity-protected quantum computation breaks the protection in a minimally invasive way, by coupling directly to the fermion parity of the system-irrespective of any quasiparticle excitations. Here, we propose to use a superconducting charge qubit in a transmission line resonator (the so-called transmon) to perform parity-protected rotations and read-out of a topological (top) qubit. The advantage over an earlier proposal using a flux qubit is that the coupling can be switched on and off with exponential accuracy, promising a reduced sensitivity to charge noise.

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

Experimental characterization of the flux-line lattice in superconducting V3Si

International Nuclear Information System (INIS)

Christen, D.; Chang, Y.; Kerchner, H.; Larson, B.; Narayan, J.; SeKula, S.

1983-01-01

Several microscopic properties of the flux-line lattice (FLL) in three separate single crystals of V 3 Si have been investigated by means of small-angle neutron diffraction. These low-field FLL characterizations have been correlated with the following material and superconducting properties: the real crystal symmetry parallel to the applied magnetic field; the micro-structure as determined by TEM; magnetic irreversibilities in the mixed state; reversible flux-line motion in ac response; martensitic structural transformation observed by X-ray diffraction. The three samples, V 3 Si-MP3, -MP4, and -MP5 possessed different defect structures, and this was manifested foremost in the FLL perfection. At low field (B 0-.5 T, but a highly mosaic, nearly polycrystalline FLL at lower fields. Sample MP4 contained large (500-1000 A) incoherent precipitates, and showed only a polycrystalline FLL at low field. In both MP3 and MP5, distinct anisotropic correlations were observed between the FLL morphology and the real-crystal direction along the applied field. The FLL perfection was strongly dependent on the growth history. The peak width history dependence for two different scattering geometries can be qualitatively modeled by proposed flux-pinning mechanisms. Quantitative comparisons with critical current measurements, however, are not totally reconcilable

Transmission line sag calculations using interval mathematics

Energy Technology Data Exchange (ETDEWEB)

Shaalan, H. [Institute of Electrical and Electronics Engineers, Washington, DC (United States)]|[US Merchant Marine Academy, Kings Point, NY (United States)

2007-07-01

Electric utilities are facing the need for additional generating capacity, new transmission systems and more efficient use of existing resources. As such, there are several uncertainties associated with utility decisions. These uncertainties include future load growth, construction times and costs, and performance of new resources. Regulatory and economic environments also present uncertainties. Uncertainty can be modeled based on a probabilistic approach where probability distributions for all of the uncertainties are assumed. Another approach to modeling uncertainty is referred to as unknown but bounded. In this approach, the upper and lower bounds on the uncertainties are assumed without probability distributions. Interval mathematics is a tool for the practical use and extension of the unknown but bounded concept. In this study, the calculation of transmission line sag was used as an example to demonstrate the use of interval mathematics. The objective was to determine the change in cable length, based on a fixed span and an interval of cable sag values for a range of temperatures. The resulting change in cable length was an interval corresponding to the interval of cable sag values. It was shown that there is a small change in conductor length due to variation in sag based on the temperature ranges used in this study. 8 refs.

Large-scale applications of superconductivity in the United States: an overview. Metallurgy, fabrication, and applications

International Nuclear Information System (INIS)

Hein, R.A.; Gubser, D.U.

1981-01-01

This report presents an overview of ongoing development efforts in the USA concerned with large-scale applications of superconductivity. These applications are grouped according to magnetic field regime, as low field regime, intermediate field regime, and high field regime. In the low field regime two diverse areas of large application are identified, superconducting power transmission lines for electric utilities, and RF cavities for particle accelerators for high energy physics research. Activity in the intermediate regime has been significantly increased due to Fermilab's energy doubler or Tevatron project, and BNL's ISABELLE project. Rotating electrical machines, such as DC acyclic (homopolar) motors, generators, and energy storage magnets are also studied. In the high field regime magnetohydrodynamics (MHD) and magnetically confined fusion in tokamaks are examined. In each regime all current work is summarized according to key person, research topic, type of program, funding, status, and future outlook

Lagrangian and Hamiltonian Formulation of Transmission Line Systems with Boundary Energy Flow

NARCIS (Netherlands)

Jeltsema, Dimitri; Schaft, Arjan J. van der

The classical Lagrangian and Hamiltonian formulation of an electrical transmission line is reviewed and extended to allow for varying boundary conditions, The method is based on the definition of an infinite-dimensional analogue of the affine Lagrangian and Hamiltonian input-output systems

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.

Shielding Effectiveness Analysis and Modification of the Coupling Effect Transmission Line Method on Cavities with Multi-Sided Apertures

Directory of Open Access Journals (Sweden)

Tao Hu

2018-04-01

Full Text Available Because the traditional transmission line method treats electromagnetic waves as excitation sources and the cavity as a rectangular waveguide whose terminal is shorted, the transmission line method can only calculate shielding effectiveness in the center line of the cavity with apertures on one side. In this paper, the aperture coupling effect of different sides was analyzed based on vector analysis. According to the field intensity distribution of different transport modes in the rectangular waveguide, the calculation model of cavity shielding effectiveness in any position is proposed, which can solve the question of the calculation model of shielding effectiveness in any position in the traditional method of equivalent transmission methods. Further expansion of the equivalent transmission lines model is adopted to study the shielding effectiveness of different aperture cavities, and the coupling effect rule of the incident angle, the number of apertures, and the size of the cavity is obtained, which can provide the technical support for the design of electromagnetic shielding cavities for electronic equipment.

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)

Sound transmission through double panel constructions lined with elastic porous materials

Science.gov (United States)

Bolton, J. S.; Green, E. R.

1986-07-01

Attention is given to a theory governing one-dimensional wave motion in elastic porous materials which is capable of reproducing experimental transmission measurements for unfaced polyurethane foam layers. Calculations of the transmission loss of fuselage-like foam-lined double panels are presented and it is shown that the foam/panel boundary conditions have a large effect on the panel performance; a hybrid arrangement whereby the foam is bonded directly to one panel and separated from the other by a thin air gap appears to be the most advantageous under practical circumstances. With this configuratiom, the mass-air-mass resonance is minimized and increased low-frequency performance is offered.

System for Relay Protection Command Transmission by High-Voltage Lines

Directory of Open Access Journals (Sweden)

D. A. Yenkov

2009-01-01

Full Text Available Development of a system for relay protection command transmission by high-voltage lines is shown in the paper. The paper describes an architecture of the system, main principles of its operation, engineering aspects of the development that is accomplishment of technical requirements, solution of trades-off. Justification of the selected design and an algorithm of the reliable detection of relay protection signals are given in the paper.

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)

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.

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.

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.

2015-06-01

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.

Scenario calculations for the 2012 grid development plan. Overdimensioned HVDC transmission lines; Szenarienrechnungen zum Netzentwicklungsplan (NEP) 2012. HGUe-Leitungen ueberdimensioniert

Energy Technology Data Exchange (ETDEWEB)

Oei, Pao-Yu; Sander, Aram; Hankel, Lisa; Laurisch, Lilian; Lorenz, Casimir [Technische Univ. Berlin (Germany); Schroeder, Andreas [Deutsches Institut fuer Wirtschaftsforschung, Berlin (Germany)

2012-09-15

The grid development plan presented in June 2012 by the German Federal Network Agency envisages a large number of new AC and DC transmission lines for Germany. The purpose of these transmission lines is to facilitate the point-to-point transport of electricity produced from renewable resources to load centres. The authors present a model-assisted analysis of the impact of these transmission lines on the structure of electricity production. They also investigate to what extent an increase in storage capacity and the steering of demand can serve as alternatives to grid expansion.

Microparticle-initiated losses in magnetically insulated transmission lines

International Nuclear Information System (INIS)

Gray, E.W.; Stinnett, R.W.

1986-01-01

The author's discuss the effects of high and hypervelocity microparticles in magnetically-insulated transmission lines (MITLs) and how they may be a possible source for ion production near the anode in early stages of the voltage pulse, and current carriers during and after the power pulse, resulting in power flow losses. Early losses in the voltage pulse, due to microparticles, are estimated to be approximately 0.3 mA/cm/sup 2/. Blistering of the electrode surface, thought to be due to H/sup -/ bombardment, was also observed and appears to be consistent with losses due to negative ions previously reported by one of the authors

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)

Tunable superconducting resonators with integrated trap structures for coupling with ultracold atomic gases

Energy Technology Data Exchange (ETDEWEB)

Ferdinand, Benedikt; Wiedmaier, Dominik; Koelle, Dieter; Kleiner, Reinhold [Physikalisches Institut and Center for Quantum Science in LISA+, Universitaet Tuebingen (Germany); Bothner, Daniel [Physikalisches Institut and Center for Quantum Science in LISA+, Universitaet Tuebingen (Germany); Kavli Institute of Nanoscience, Delft University of Technology, Delft (Netherlands)

2016-07-01

We intend to investigate a hybrid quantum system where ultracold atomic gases play the role of a long-living quantum memory, coupled to a superconducting qubit via a coplanar waveguide transmission line resonator. As a first step we developed a resonator chip containing a Z-shaped trapping wire for the atom trap. In order to suppress parasitic resonances due to stray capacitances, and to achieve good ground connection we use hybrid superconductor - normal conductor chips. As an additional degree of freedom we add a ferroelectric capacitor making the resonators voltage-tunable. We furthermore show theoretical results on the expected coupling strength between resonator and atomic cloud.

AC loss in superconducting tapes and cables

NARCIS (Netherlands)

Oomen, M.P.

2000-01-01

The present study discusses the AC loss in high-temperature superconductors. Superconducting materials with a relatively high critical temperature were discovered in 1986. They are presently developed for use in large-scale power-engineering devices such as power-transmission cables, transformers

A novel structure of transmission line pulse transformer with mutually coupled windings.

Science.gov (United States)

Yu, Binxiong; Su, Jiancang; Li, Rui; Zhao, Liang; Zhang, Xibo; Wang, Junjie

2014-03-01

A novel structure of transmission line transformer (TLT) with mutually coupled windings is described in this paper. All transmission lines except the first stage of the transformer are wound on a common ferrite core for the TLT with this structure. A referral method was introduced to analyze the TLT with this structure, and an analytic expression of the step response was derived. It is shown that a TLT with this structure has a significantly slower droop rate than a TLT with other winding structures and the number of ferrite cores needed is largely reduced. A four-stage TLT with this structure was developed, whose input and output impedance were 4.2 Ω and 67.7 Ω, respectively. A frequency response test of the TLT was carried out. The test results showed that pulse response time of the TLT is several nanoseconds. The TLT described in this paper has the potential to be used as a rectangle pulse transformer with very fast response time.

Interplay between superconductivity and Coulomb blockade

Energy Technology Data Exchange (ETDEWEB)

Lorenz, Thomas; Sprenger, Susanne; Scheer, Elke [Universitaet Konstanz (Germany)

2016-07-01

Studying the interplay between superconductivity and Coulomb blockade (CB) can be achieved by investigating an all superconducting single electron transistor (SSET) consisting of an island coupled to the leads by two tunneling contacts. The majority of experiments performed so far were using superconducting tunnel contacts made from oxide layers, in which multiple Andreev reflections (MAR) can be excluded. Using a mechanically controlled break junction (MCBJ) made of aluminum enables tuning the contributions of MAR in one junction continuously and thereby addressing different transport regimes within the same sample. Our results offer the possibility to attribute particular features in the transport characteristics to the transmission probabilities of individual modes in the MCBJ contact. We discuss our findings in terms of dynamical CB, SSET behaviour and MAR when continuously opening the MCBJ from the fully closed state to a tunneling contact.

One-Step Generation of Multi-Qubit GHZ and W States in Superconducting Transmon Qubit System

International Nuclear Information System (INIS)

Gao Guilong; Huang Shousheng; Wang Mingfeng; Jiang Nianquan; Cai Genchang

2012-01-01

We propose a one-step method to prepare multi-qubit GHZ and W states with transmon qubits capacitively coupled to a superconducting transmission line resonator (TLR). Compared with the scheme firstly introduced by Wang et al. [Phys. Rev. B 81 (2010) 104524], our schemes have longer dephasing time and much shorter operation time because the transmon qubits we used are not only more robust to the decoherence and the unavoidable parameter variations, but also have much stronger coupling constant with TLR. Based on the favourable properties of transmons and TLR, our method is more feasible in experiment. (general)

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.

Electrostatic induction under the Tanashi test transmission line

Energy Technology Data Exchange (ETDEWEB)

Kitani, Y; Yokata, S

1964-06-01

Experimental results are given on the electrostatic voltage induced in small and medium-sized motorcars under the Tanashi 800 kV Test Transmission Line, which is of horizontal arrangement, 200 m span, four bundle conductors and average height of 13.52 m. The induced voltage was measured between 1600 and 3000 V under the line voltage of 520 kV. The voltage and current were measured with four kinds of model motorcars in air and water, and results of the measurements are compared with those of actual measurements with good agreements. The values of capacity and leakage resistance, whose parallel circuit was considered to represent an equivalent circuit of the motorcar, were measured with a Maxwell-Wien bridge at frequencies between 30 and 1000 c/s. It was found that the values at 60 c/s were measured to be approximately six or seven times higher than its values at 1000 c/s, and that new tires have higher conductivities than the old ones, reducing the electrostatic induction voltage by a large amount.

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

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.

The Quantum Socket: Wiring for Superconducting Qubits - Part 2

Science.gov (United States)

Bejanin, J. H.; McConkey, T. G.; Rinehart, J. R.; Bateman, J. D.; Earnest, C. T.; McRae, C. H.; Rohanizadegan, Y.; Shiri, D.; Mariantoni, M.; Penava, B.; Breul, P.; Royak, S.; Zapatka, M.; Fowler, A. G.

Quantum computing research has reached a level of maturity where quantum error correction (QEC) codes can be executed on linear arrays of superconducting quantum bits (qubits). A truly scalable quantum computing architecture, however, based on practical QEC algorithms, requires nearest neighbor interaction between qubits on a two-dimensional array. Such an arrangement is not possible with techniques that rely on wire bonding. To address this issue, we have developed the quantum socket, a device based on three-dimensional wires that enables the control of superconducting qubits on a two-dimensional grid. In this talk, we present experimental results characterizing this type of wiring. We will show that the quantum socket performs exceptionally well for the transmission and reflection of microwave signals up to 10 GHz, while minimizing crosstalk between adjacent wires. Under realistic conditions, we measured an S21 of -5 dB at 6 GHz and an average crosstalk of -60 dB. We also describe time domain reflectometry results and arbitrary pulse transmission tests, showing that the quantum socket can be used to control superconducting qubits.

Analysis of lightning fault detection, location and protection on short and long transmission lines using Real Time Digital Simulation

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Andre Luiz Pereira de [Siemens Ltda., Sao Paulo, SP (Brazil)], E-mail: andreluiz.oliveira@siemens.com

2007-07-01

The purpose of this paper is to present an analysis of lightning fault detection, location and protection using numeric distance relays applied in high voltage transmission lines, more specifically in the 500 kV transmission lines of CEMIG (Brazilian Energy Utility) between the Vespasiano 2 - Neves 1 (short line - 23.9 km) and Vespasiano 2 - Mesquita (long line - 148.6 km) substations. The analysis was based on the simulations results of numeric distance protective relays on power transmission lines, realized in September 02 to 06, 2002, at Siemens AG's facilities (Erlangen - Germany), using Real Time Digital Simulator (RTDS{sup TM}). Several lightning faults simulations were accomplished, in several conditions of the electrical power system where the protective relays would be installed. The results are presented not only with the times of lightning faults elimination, but also all the functionality of a protection system, including the correct detection, location and other advantages that these modern protection devices make possible to the power system. (author)

Conceptual study of superconducting urban area power systems

International Nuclear Information System (INIS)

Noe, Mathias; Gold-acker, Wilfried; Bach, Robert; Prusseit, Werner; Willen, Dag; Poelchau, Juri; Linke, Christian

2010-01-01

Efficient transmission, distribution and usage of electricity are fundamental requirements for providing citizens, societies and economies with essential energy resources. It will be a major future challenge to integrate more sustainable generation resources, to meet growing electricity demand and to renew electricity networks. Research and development on superconducting equipment and components have an important role to play in addressing these challenges. Up to now, most studies on superconducting applications in power systems have been concentrated on the application of specific devices like for example cables and current limiters. In contrast to this, the main focus of our study is to show the consequence of a large scale integration of superconducting power equipment in distribution level urban power systems. Specific objectives are to summarize the state-of-the-art of superconducting power equipment including cooling systems and to compare the superconducting power system with respect to energy and economic efficiency with conventional solutions. Several scenarios were considered starting from the replacement of an existing distribution level sub-grid up to a full superconducting urban area distribution level power system. One major result is that a full superconducting urban area distribution level power system could be cost competitive with existing solutions in the future. In addition to that, superconducting power systems offer higher energy efficiency as well as a number of technical advantages like lower voltage drops and improved stability.

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.

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

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.

Lossy transmission line model of hydrofractured well dynamics

Energy Technology Data Exchange (ETDEWEB)

Patzek, T.W. [Department of Materials Science and Mineral Engineering, University of California at Berkeley, Berkeley, CA (United States); De, A. [Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

2000-01-01

The real-time detection of hydrofracture growth is crucial to the successful operation of water, CO{sub 2} or steam injection wells in low-permeability reservoirs and to the prevention of subsidence and well failure. In this paper, we describe propagation of very low frequency (1-10 to 100 Hz) Stoneley waves in a fluid-filled wellbore and their interactions with the fundamental wave mode in a vertical hydrofracture. We demonstrate that Stoneley-wave loses energy to the fracture and the energy transfer from the wellbore to the fracture opening is most efficient in soft rocks. We conclude that placing the wave source and receivers beneath the injection packer provides the most efficient means of hydrofracture monitoring. We then present the lossy transmission line model of wellbore and fracture for the detection and characterization of fracture state and volume. We show that this model captures the wellbore and fracture geometry, the physical properties of injected fluid and the wellbore-fracture system dynamics. The model is then compared with experimentally measured well responses. The simulated responses are in good agreement with published experimental data from several water injection wells with depths ranging from 1000 ft to 9000 ft. Hence, we conclude that the transmission line model of water injectors adequately captures wellbore and fracture dynamics. Using an extensive data set for the South Belridge Diatomite waterfloods, we demonstrate that even for very shallow wells the fracture size and state can be adequately recognized at wellhead. Finally, we simulate the effects of hydrofracture extension on the transient response to a pulse signal generated at wellhead. We show that hydrofracture extensions can indeed be detected by monitoring the wellhead pressure at sufficiently low frequencies.

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 inclu...... simulations of the DSRR structures. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1311–1315, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25988...

Sound transmission through triple-panel structures lined with poroelastic materials

OpenAIRE

Liu, Y

2015-01-01

In this paper, previous theories on the prediction of sound transmission loss for a double-panel structure lined with poroelastic materials are extended to address the problem of a triple-panel structure. Six typical configurations are considered for a triple-panel structure based on the method of coupling the porous layers to the facing panels which determines critically the sound insulation performance of the system. The transfer matrix method is employed to solve the system by applying app...

Calculation of large ion densities under HVdc transmission lines by the finite difference method

International Nuclear Information System (INIS)

Suda, Tomotaka; Sunaga, Yoshitaka

1995-01-01

A calculation method for large ion densities (charged aerosols) under HVdc transmission lines was developed considering both the charging mechanism of aerosols by small ions and the drifting process by wind. Large ion densities calculated by this method agreed well with the ones measured under the Shiobara HVdc test line on the lateral profiles at ground level up to about 70m downwind from the line. Measured values decreased more quickly than calculated ones farther downwind from the line. Considering the effect of point discharge from ground cover (earth corona) improved the agreement in the farther downwind region

Superconductivity an introduction

CERN Document Server

Kleiner, Reinhold

2016-01-01

The third edition of this proven text has been developed further in both scope and scale to reflect the potential for superconductivity in power engineering to increase efficiency in electricity transmission or engines. The landmark reference remains a comprehensive introduction to the field, covering every aspect from fundamentals to applications, and presenting the latest developments in organic superconductors, superconducting interfaces, quantum coherence, and applications in medicine and industry. Due to its precise language and numerous explanatory illustrations, it is suitable as an introductory textbook, with the level rising smoothly from chapter to chapter, such that readers can build on their newly acquired knowledge. The authors cover basic properties of superconductors and discuss stability and different material groups with reference to the latest and most promising applications, devoting the last third of the book to applications in power engineering, medicine, and low temperature physics. An e...

Design of a synchrotron radiation detector for the test beam lines at the Superconducting Super Collider Laboratory

International Nuclear Information System (INIS)

Hutton, R.D.

1994-01-01

As part of the particle- and momentum-tagging instrumentation required for the test beam lines of the Superconducting Super Collider (SSC), the synchrotron radiation detector (SRD) was designed to provide electron tagging at momentum above 75 GeV. In a parallel effort to the three test beam lines at the SSC, schedule demands required testing and calibration operations to be initiated at Fermilab. Synchrotron radiation detectors also were to be installed in the NM and MW beam lines at Femilab before the test beam lines at the SSC would become operational. The SRD is the last instrument in a series of three used in the SSC test beam fines. It follows a 20-m drift section of beam tube downstream of the last silicon strip detector. A bending dipole just in of the last silicon strip detector produces the synchrotron radiation that is detected in a 50-mm-square cross section NaI crystal. A secondary scintillator made of Bicron BC-400 plastic is used to discriminate whether it is synchrotron radiation or a stray particle that causes the triggering of the NaI crystal's photo multiplier tube (PMT)

Technical and economic data for overhead lines in high-voltage a. c. and d. c. transmission

Energy Technology Data Exchange (ETDEWEB)

1977-11-01

For the study of 'High-power electricity transmission and distribution in densely populated areas' technical and economic data were compiled for high-voltage alternating current and direct current transmission. A modification of the overhead lines for transmitting higher powers is possible as required by means of higher rated transmission voltages, larger conductor cross-sections and a larger number of circuits installed on each mast. For the use of larger partial conductor cross-sections and of bundle conductors with more than 4 partial conductors, and also to use voltages higher than 380 kV, development work is requisite from the points of view of construction, installation, insulators and fittings. Further possible developments result from the use of new materials such as plastic insulators which make possible the use of more versatile shapes for application in heavy pollution, particulary for direct current overhead lines. By using insulating crossarms the width of path can be considerably reduced. Economic efficiency investigations show even today higher cost for such techniques compared with lines of earlier construction.

Summer Course on the Science and Technology of Superconductivity

CERN Document Server

Gregory, W D; Mathews, W N; The science and technology of superconductivity

1973-01-01

Since the discovery of superconductivity in 1911 by H. Kamerlingh Onnes, of the order of half a billion dollars has been spent on research directed toward understanding and utiliz­ ing this phenomenon. This investment has gained us fundamental understanding in the form of a microscopic theory of superconduc­ tivity. Moreover, superconductivity has been transformed from a laboratory curiosity to the basis of some of the most sensitive and accurate measuring devices known, a whole host of other elec­ tronic devices, a soon-to-be new international standard for the volt, a prototype generation of superconducting motors and gener­ ators, and magnets producing the highest continuous magnetic fields yet produced by man. The promise of more efficient means of power transmission and mass transportation, a new generation of superconducting motors and generators, and computers and other electronic devices with superconducting circuit elements is all too clear. The realization of controlled thermonuclear fu...

DEVELOPMENT AND INVESTIGATION OF LAYOUT OF ACTIVE SCREENING SYSTEM OF THE MAGNETIC FIELD GENERATED BY GROUP OF OVERHEAD TRANSMISSION LINES

Directory of Open Access Journals (Sweden)

B. I. Kuznetsov

2018-04-01

Full Text Available Purpose. Development and field experimental research of layout of the single-circuit active screening system of the magnetic field generated by group of high voltage transmission lines in residential area is given. Methodology. Mathematical model of magnetic field, generated by group of high voltage transmission lines in residential area, based of the experimental values of magnetic field flux density in given points on the basis of optimization problem solving is improved. The objective of the synthesis of the single circuit active screening 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 magnetic flux density at the points of the protected space. Synthesis of the full-scale model of active screening 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 the Maxwell equations solutions in the quasi-stationary approximation. The problem is solved by a stochastic multiswarm multi-agent particles optimization. Results. The single-circuit active screening system synthesis results for reduction of a magnetic field generated by group of high voltage transmission lines in residential area is given. Field experimental researches of the single-circuit active screening system of the magnetic field generated by group of high voltage transmission lines in residential area with various control algorithms is given. Originality. For the first time out the development and field experimental studies of the single-circuit active screening system of the magnetic field generated by group of high voltage transmission lines in residential area are carried out. Practical value. Practical recommendations on reasonable choice of the spatial arrangement of compensating cables of single

Superconducting nanowires as nonlinear inductive elements for qubits

Science.gov (United States)

Ku, Jaseung; Manucharyan, Vladimir; Bezryadin, Alexey

2011-03-01

We report microwave transmission measurements of superconducting Fabry-Perot resonators, having a superconducting nanowire placed at a supercurrent antinode. As the plasma oscillation is excited, the supercurrent is forced to flow through the nanowire. The microwave transmission of the resonator-nanowire device shows a nonlinear resonance behavior, significantly dependent on the amplitude of the supercurrent oscillation. We show that such amplitude-dependent response is due to the nonlinearity of the current-phase relationship of the nanowire. The results are explained within a nonlinear oscillator model of the Duffing oscillator, in which the nanowire acts as a purely inductive element, in the limit of low temperatures and low amplitudes. The low-quality factor sample exhibits a ``crater'' at the resonance peak at higher driving power, which is due to dissipation. We observe a hysteretic bifurcation behavior of the transmission response to frequency sweep in a sample with a higher quality factor. The Duffing model is used to explain the Duffing bistability diagram. NSF DMR-1005645, DOE DO-FG02-07ER46453.

Programs on large scale applications of superconductivity in Japan

International Nuclear Information System (INIS)

Yasukochi, K.; Ogasawara, T.

1974-01-01

History of the large scale application of superconductivity in Japan is reported. Experimental works on superconducting magnet systems for high energy physics have just begun. The programs are described by dividing into five categories: 1) MHD power generation systems, 2) superconducting rotating machines, 3) cryogenic power transmission systems, 4) magnetically levitated transportation, and 5) application to high energy physics experiments. The development of a big superconducting magnet for a 1,000 kW class generator was set up as a target of first seven year plan, which came to end in 1972, and continues for three years with the budget of 900 million yen from 1973 on. In the second phase plan, a prototype MHD generator is argued. A plan is contemplated to develop a synchronous generator with inner rotating field by Fuji Electric Co. The total budget for the future plans of superconducting power transmission system amounts to 20 billion yen for the first period of 8 approximately 9 years. In JNR's research and development efforts, several characteristic points are picked up: 1) linear motor drive with active side on ground, 2) loop track, 3) combined test run of maglev and LSM. The field test at the speed of 500 km/hr on a 7 km track is scheduled to be performed in 1975. The target of operation is in 1985. A 12 GeV proton synchrotron is now under construction for the study on high energy physics. Three ring intersecting storage accelerator is discussed for future plan. (Iwakiri, K.)

Lattice parameters guide superconductivity in iron-arsenides

Science.gov (United States)

Konzen, Lance M. N.; Sefat, Athena S.

2017-03-01

The discovery of superconducting materials has led to their use in technological marvels such as magnetic-field sensors in MRI machines, powerful research magnets, short transmission cables, and high-speed trains. Despite such applications, the uses of superconductors are not widespread because they function much below room-temperature, hence the costly cooling. Since the discovery of Cu- and Fe-based high-temperature superconductors (HTS), much intense effort has tried to explain and understand the superconducting phenomenon. While no exact explanations are given, several trends are reported in relation to the materials basis in magnetism and spin excitations. In fact, most HTS have antiferromagnetic undoped ‘parent’ materials that undergo a superconducting transition upon small chemical substitutions in them. As it is currently unclear which ‘dopants’ can favor superconductivity, this manuscript investigates crystal structure changes upon chemical substitutions, to find clues in lattice parameters for the superconducting occurrence. We review the chemical substitution effects on the crystal lattice of iron-arsenide-based crystals (2008 to present). We note that (a) HTS compounds have nearly tetragonal structures with a-lattice parameter close to 4 Å, and (b) superconductivity can depend strongly on the c-lattice parameter changes with chemical substitution. For example, a decrease in c-lattice parameter is required to induce ‘in-plane’ superconductivity. The review of lattice parameter trends in iron-arsenides presented here should guide synthesis of new materials and provoke theoretical input, giving clues for HTS.

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 (0<α≤1) of the derivative operator 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.

Insulation design of cryogenic bushing for superconducting electric power applications

Energy Technology Data Exchange (ETDEWEB)

Koo, J.Y., E-mail: koojy@hanyang.ac.kr [Department of Electronics, Electrical, Control and Instrumentation Engineering, Hanyang University, Ansan 426-791 (Korea, Republic of); Lee, Y.J.; Shin, W.J.; Kim, Y.H. [Department of Electronics, Electrical, Control and Instrumentation Engineering, Hanyang University, Ansan 426-791 (Korea, Republic of); Kim, J.T. [Department of Electrical Engineering, Daejin University, Pocheon 487-711 (Korea, Republic of); Lee, B.W. [Department of Electronics, Electrical, Control and Instrumentation Engineering, Hanyang University, Ansan 426-791 (Korea, Republic of); Lee, S.H., E-mail: k720lsh@kins.re.kr [Expert Group Electric and Control Department, Korea Institute of Nuclear Safety, Daejeon 305-600 (Korea, Republic of)

2013-01-15

Highlights: ► In this paper, design factors of cryogenic bushings were discussed and test results of specimen were introduced in detail. ► We focused on the comparative study of breakdown characteristics of different electrode materials. ► Puncture and creepage breakdown characteristics were analyzed based on the withstand voltage. ► We obtained the basic design factors of extra high voltage condenser bushing. ► We obtained the basic design factors of extra high voltage condenser bushing, which could be used in cryogenic environment. -- Abstract: Recently, the superconductivity projects to develop commercial superconducting devices for extra high voltage transmission lines have been undergoing in many countries. One of the critical components to be developed for high voltage superconducting devices, including superconducting transformers, cables, and fault current limiters, is a high voltage bushing, to supply high current to devices without insulating difficulties, that is designed for cryogenic environments. Unfortunately, suitable bushings for HTS equipment were not fully developed for some cryogenic insulation issues. Such high voltage bushings would need to provide electrical insulation capabilities from room temperature to cryogenic temperatures. In this paper, design factors of cryogenic bushings were discussed and test results of specimen were introduced in detail. First, the dielectric strength of three kinds of metals has been measured with uniform and non-uniform electrodes by withstand voltage of impulse and AC breakdown test in LN{sub 2}. Second, puncture breakdown voltage of glass fiber reinforced plastics (GFRPs) plates has been analyzed with non-uniform electrodes. Finally, creepage discharge voltages were measured according to the configuration of non-uniform and uniform electrode on the FRP plate. From the test results, we obtained the basic design factors of extra high voltage condenser bushing, which could be used in cryogenic

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.

Review of fire behavior during passage of Sandy Lake Fire 13 (NWT) across a Northwest Territories Power Corporation transmission line

Energy Technology Data Exchange (ETDEWEB)

Schroeder, D.; Thomasson, J.

2009-03-15

The Sandy Lake Fire 13 of July 2008 was an intense forest fire that burned up to and across a power line right-of-way in the Northwest Territories, approximately 160 km northwest of Fort Smith. The terrain in the area is flat and vegetation is characterized by boreal pine and black spruce uplands with black spruce and tamarack in lower areas and adjacent to wetlands. This report documented post fire conditions at locations where the fire crossed the power line. The towers on this line were made from an aluminum alloy and may not have had the same resistance to heat damage as steel towers, more commonly used on major transmission lines. The transmission line was de-energized during the fire. Therefore, the effects of fire on power transmission were not documented. Although the intense wildfire crossed sections of the power line, it did not result in observable damage to the towers or lines. Fire intensity was likely greater than 40,000 kw/m along some sections of the right-of-way. Although the management of the right-of-way may have reduced heat exposure to the transmission towers, it did not stop the fire. Pine mixed with an aspen component greater than 50 per cent had a mitigating effect on fire behaviour. The fire did not result in any immediate damage to the power line infrastructure. It was concluded that the use of power lines for fire operations should consider right-of-way width in order to assess equipment maneuverability, especially around tower guy wires. 5 refs., 1 tab., 12 figs.

Implementation of a microcomputer based distance relay for parallel transmission lines

International Nuclear Information System (INIS)

Phadke, A.G.; Jihuang, L.

1986-01-01

Distance relaying for parallel transmission lines is a difficult application problem with conventional phase and ground distance relays. It is known that for cross-country faults involving dissimilar phases and ground, three phase tripping may result. This paper summarizes a newly developed microcomputer based relay which is capable of classifying the cross-country fault correctly. The paper describes the principle of operation and results of laboratory tests of this relay

Characterization of the microwave properties of superconducting films with high transition temperature

International Nuclear Information System (INIS)

Richter, W.; Klinger, M.; Daginnus, M.

1989-01-01

In the meantime high quality Y-Ba-Cu-O thin films were produced. The latest results show, that its surface resistances are clearly lower than the values of copper, measured at a temperature of 77 K and up to frequencies of 86 GHz. This examination had the aim to produce high-T c films with a simple and low cost method, to use them as transmission lines at frequencies up to 30 GHz and above. A screen printing process was investigated, and high-T c thick films were fabricated on several substrates. Superconducting transition temperatures up to 80 K (dc zero resistance) were obtained. The films showed no complete magnetic shielding, and its microwave surface resistances were clearly higher than that ones for copper. The a. c. Josephson effect was proved with granular structures of bulk Y-Ba-Cu-O material and with screen printed thick films. Because of its high surface resistances, these thick films are unsuitable for the use as transmission lines at high frequencies. However, the a.c. Josephson effect can be used to manufacture microwave sensors in bulk Y-Ba-Cu-O and screen printed films of Y-Ba-Cu-O, which have a favourable geometric structure. (orig.) With 16 refs., 2 tabs., 24 figs [de

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.

Superconducting transformers, rectifiers, and switches. (Review paper)

International Nuclear Information System (INIS)

Ignatov, V.E.; Koval'kov, G.A.; Moskvitin, A.I.

Cryogenic rectifiers using power cryotrons have been fabricated by many foreign firms since 1960. Present-day flux pumps require a low voltage power supply (several tens of millivolts) and a high current (kiloamperes). Increasing the power supply voltage will quadratically increase the flux pump losses and, given the limitations of existing materials, are not economically profitable. Present-day, cryotron-type flux pumps can best be used in power systems as a power supply for superconducting magnets, solenoids, storage devices, and superconducting exciting coils for turbogenerators. To increase the voltage of the next generation of transformers for superconducting dc power transmission, a research program must be set up to improve the cryotrons and to develop systems based on a different principle of operation, for example, semiconductor devices based on the principle of the volume effect in the intermediate environment

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.

100 Years of Superconductivity: Perspective on Energy Applications

Science.gov (United States)

Grant, Paul

2011-11-01

One hundred years ago this past April, in 1911, traces of superconductivity were first detected near 4.2 K in mercury in the Leiden laboratory of Kammerlingh Onnes, followed seventy-five years later in January, 1986, by the discovery of ``high temperature'' superconductivity above 30 K in layered copper oxide perovskites by Bednorz and Mueller at the IBM Research Laboratory in Rueschlikon. Visions of application to the electric power infrastructure followed each event, and the decades following the 1950s witnessed numerous, successful demonstrations to electricity generation, transmission and end use -- rotating machinery, cables, transformers, storage, current limiters and power conditioning, employing both low and high temperature superconductors in the USA, Japan, Europe, and more recently, China. Despite these accomplishments, there has been to date no substantial insertion of superconducting technology in the electric power infrastructure worldwide, and its eventual deployment remains problematic. We will explore the issues delaying such deployment and suggest future electric power scenarios where superconductivity will play an essential central role.

Quantum heat engine with coupled superconducting resonators

Science.gov (United States)

Hardal, Ali Ü. C.; Aslan, Nur; Wilson, C. M.; Müstecaplıoǧlu, Özgür E.

2017-12-01

We propose a quantum heat engine composed of two superconducting transmission line resonators interacting with each other via an optomechanical-like coupling. One resonator is periodically excited by a thermal pump. The incoherently driven resonator induces coherent oscillations in the other one due to the coupling. A limit cycle, indicating finite power output, emerges in the thermodynamical phase space. The system implements an all-electrical analog of a photonic piston. Instead of mechanical motion, the power output is obtained as a coherent electrical charging in our case. We explore the differences between the quantum and classical descriptions of our system by solving the quantum master equation and classical Langevin equations. Specifically, we calculate the mean number of excitations, second-order coherence, as well as the entropy, temperature, power, and mean energy to reveal the signatures of quantum behavior in the statistical and thermodynamic properties of the system. We find evidence of a quantum enhancement in the power output of the engine at low temperatures.

Laser patterning of superconducting oxide films

International Nuclear Information System (INIS)

Gupta, A.; Hussey, B.W.; Koren, G.; Cooper, E.I.; Jagannathan, R.

1988-01-01

The focused output of an argon ion laser (514.5 nm) has been used for wiring superconducting lines of Y/sub 1/Ba/sub 2/CU/sub 3/O/sub 7-δ/ using films prepared from nitrate and trifluoroacetate solution precursors. A stoichiometric solution of the precursors is sprayed or spun on to the substrate to form a film. The film is patterned by irradiating in selected areas to convert the irradiated layers to an intermediate oxide or fluoride state, the nonirradiated areas being unchanged. The nonirradiated areas are then dissolved away, leaving a pattern of the oxide or fluoride material. This patterned layer is converted to the superconducting 1-2-3 oxide in a subsequent annealing step. Maskless patterning of superconducting films has also been demonstrated by laser-assisted etching of the films in aqueous KOH solution. Although superconductivity is destroyed when the films are placed in solution, it can be restored after a brief anneal in oxygen

Superconductivity observed in platinum-silicon interface

Energy Technology Data Exchange (ETDEWEB)

Kuo, Pai-Chia, E-mail: paichia@phys.sinica.edu.tw [Research Program on Nanoscience and Nanotechnology, Academia Sinica, Taipei 11529, Taiwan (China); Institute of Physics, Academia Sinica, Taipei 11529, Taiwan (China); Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Chen, Chun-Wei [Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Lee, Ku-Pin; Shiue, Jessie, E-mail: yshiue@phys.sinica.edu.tw [Research Program on Nanoscience and Nanotechnology, Academia Sinica, Taipei 11529, Taiwan (China); Institute of Physics, Academia Sinica, Taipei 11529, Taiwan (China)

2014-05-26

We report the discovery of superconductivity with an onset temperature of ∼0.6 K in a platinum-silicon interface. The interface was formed by using a unique focused ion beam sputtering micro-deposition method in which the energies of most sputtered Pt atoms are ∼2.5 eV. Structural and elemental analysis by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy reveal a ∼ 7 nm interface layer with abundant Pt, which is the layer likely responsible for the superconducting transport behavior. Similar transport behavior was also observed in a gold-silicon interface prepared by the same technique, indicating the possible generality of this phenomenon.

Dynamic motion modes of high temperature superconducting maglev on a 45-m long ring test line

Science.gov (United States)

Lei, W. Y.; Qian, N.; Zheng, J.; Jin, L. W.; Zhang, Y.; Deng, Z. G.

2017-10-01

With the development of high temperature superconducting (HTS) maglev, studies on the running stability have become more and more significant to ensure the operation safety. An experimental HTS maglev vehicle was tested on a 45-m long ring test line under the speed from 4 km/h to 20 km/h. The lateral and vertical acceleration signals of each cryostat were collected by tri-axis accelerometers in real time. By analyzing the phase relationship of acceleration signals on the four cryostats, several typical motion modes of the HTS maglev vehicle, including lateral, yaw, pitch and heave motions were observed. This experimental finding is important for the next improvement of the HTS maglev system.

Development of a superconducting cable for transmission of high electric power

International Nuclear Information System (INIS)

Moisson, F.; Leroux, J.M.

1971-01-01

The opportunities opened by the use of cryoresistive and superconducting materials in underground transmission systems have led to a cryocable program. A first set of problems associated with the development of cryogenic cables deals with the cable system, i.e., design, safety, terminal equipment including leads, cryogenic equipment, refrigerators, and problems related to overload capability and reliability. A second set concerns the cable itself, i.e., scientific and technological problems associated with the conductor, the electrical insulation, and the thermal exchange between conductor and helium. Useful experience is gained on the design problems and on the technological problems involved in the construction of a cryoconducting cable. A 20-M aluminum cable cooled down to 25 0 K with pressurized helium flow was built and tested with 3500-A dc under 20 Kv; results are presented. On this model the following types of problems were solved. First, mechanical problems concerning cooling of the cable, thermal contraction of the pipes, electrical insulation and conductors, construction of an invariable cable constituted by elementary helically wound conductors were solved. Second, thermal problems of reduction of heat leaks, conception of thermal insulation, and segmentation of vacuum jackets were solved. Third, electrical problems of design of 300 0 to 25 0 K leads were solved; this problem of losses at both ends is, in proportion, more important for the short model than for long cable. Finally, refrigeration problems of helium and nitrogen flows, thermal shields and design of refrigerators (optimal capacity and spacing) were solved

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.

Optical modeling of fiber organic photovoltaic structures using a transmission line method.

Science.gov (United States)

Moshonas, N; Stathopoulos, N A; O'Connor, B T; Bedeloglu, A Celik; Savaidis, S P; Vasiliadis, S

2017-12-01

An optical model has been developed and evaluated for the calculation of the external quantum efficiency of cylindrical fiber photovoltaic structures. The model is based on the transmission line theory and has been applied on single and bulk heterojunction fiber-photovoltaic cells. Using this model, optimum design characteristics have been proposed for both configurations, and comparison with experimental results has been assessed.

An ME-PC Enhanced HDMR Method for Efficient Statistical Analysis of Multiconductor Transmission Line Networks

KAUST Repository

Yucel, Abdulkadir C.; Bagci, Hakan; Michielssen, Eric

2015-01-01

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

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....

Superconductivity

International Nuclear Information System (INIS)

Palmieri, V.

1990-01-01

This paper reports on superconductivity the absence of electrical resistance has always fascinated the mind of researchers with a promise of applications unachievable by conventional technologies. Since its discovery superconductivity has been posing many questions and challenges to solid state physics, quantum mechanics, chemistry and material science. Simulations arrived to superconductivity from particle physics, astrophysic, electronics, electrical engineering and so on. In seventy-five years the original promises of superconductivity were going to become reality: a microscopical theory gave to superconductivity the cloth of the science and the level of technological advances was getting higher and higher. High field superconducting magnets became commercially available, superconducting electronic devices were invented, high field accelerating gradients were obtained in superconductive cavities and superconducting particle detectors were under study. Other improvements came in a quiet progression when a tornado brought a revolution in the field: new materials had been discovered and superconductivity, from being a phenomenon relegated to the liquid Helium temperatures, became achievable over the liquid Nitrogen temperature. All the physics and the technological implications under superconductivity have to be considered ab initio

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.

Superconducting Microwave Resonator Arrays for Submillimeter/Far-Infrared Imaging

Science.gov (United States)

Noroozian, Omid

Superconducting microwave resonators have the potential to revolutionize submillimeter and far-infrared astronomy, and with it our understanding of the universe. The field of low-temperature detector technology has reached a point where extremely sensitive devices like transition-edge sensors are now capable of detecting radiation limited by the background noise of the universe. However, the size of these detector arrays are limited to only a few thousand pixels. This is because of the cost and complexity of fabricating large-scale arrays of these detectors that can reach up to 10 lithographic levels on chip, and the complicated SQUID-based multiplexing circuitry and wiring for readout of each detector. In order to make substantial progress, next-generation ground-based telescopes such as CCAT or future space telescopes require focal planes with large-scale detector arrays of 104--10 6 pixels. Arrays using microwave kinetic inductance detectors (MKID) are a potential solution. These arrays can be easily made with a single layer of superconducting metal film deposited on a silicon substrate and pattered using conventional optical lithography. Furthermore, MKIDs are inherently multiplexable in the frequency domain, allowing ˜ 10 3 detectors to be read out using a single coaxial transmission line and cryogenic amplifier, drastically reducing cost and complexity. An MKID uses the change in the microwave surface impedance of a superconducting thin-film microresonator to detect photons. Absorption of photons in the superconductor breaks Cooper pairs into quasiparticles, changing the complex surface impedance, which results in a perturbation of resonator frequency and quality factor. For excitation and readout, the resonator is weakly coupled to a transmission line. The complex amplitude of a microwave probe signal tuned on-resonance and transmitted on the feedline past the resonator is perturbed as photons are absorbed in the superconductor. The perturbation can be

Tetracritical point and current circulations in superconducting state

International Nuclear Information System (INIS)

Belyavskij, V.I.; Kopaev, Yu.V.; Smirnov, M.Yu.

2005-01-01

Phase diagram reflecting the key peculiar features of the standard diagram of the cuprate superconductors was studied in terms of the Ginzburg-Landau phenomenology near the tetracritical point resulting from the competition of superconducting and dielectric channels of pairing. Two-component parameter of order the relative phase of which is associated with antiferromagnetic dielectric ordering corresponds to the superconducting pairing at repulsion. In case of slight doping the dielectric order coexists with superconductivity below the temperature of superconducting phase transition and manifests itself as a slight pseudoslit above the mentioned temperature. A segment of pseudoslit region adjacent to the superconducting state corresponds to the matured fluctuations of the order parameter in the form of quasi-stationary states of noncoherent superconducting pairs and may be interpreted as a region of a strong pseudoslit. At increase of doping one observes a phase transition from the coexistence region and the orbital antiferromagnetism to the conventional superconducting state covering the region of matured fluctuations of the order parameter in the form of quasi-stationary states of the noncorrelated orbital circulation currents adjacent to the line of phase transition [ru

Method of selecting optimum cross arm lengths for a 750 kV transmission line

Energy Technology Data Exchange (ETDEWEB)

Aleksandrov, G N; Olorokov, V P

1965-01-01

A method is presented, based on both technical and economic considerations, for selecting cross arm lengths for intermediate poles of power transmission lines according to the effects of internal overvoltage, methods from probability theory and mathematical statistics employed. The problem of optimum pole size is considered in terms of the effect of internal overvoltages for a prescribed maximum level of 2.1 PU currently used in the USSR for the design of 750 kV lines.

Thermal Rectification in Graded Nonlinear Transmission Lines

International Nuclear Information System (INIS)

Xu Wen; Chen Wei-Zhong; Tao Feng

2011-01-01

We consider heat conduction in a nonlinear inductance-capacitance (LC) transmission line with an inductance gradient by adding white-noise signals. It is found that the heat flux in the direction of inductance decrease is larger than that in the direction of inductance increase. When the low-inductance end is at higher temperature, the phonon density decreases due to conversion to high-frequency phonons, which can not move to the high-inductance end due to its lower cutoff frequency. However, when the high-inductance end is at higher temperature, the loss of phonon density can be compensated for because some high-frequency phonons can move to the low-inductance end dur to its higher cutoff frequency. This leads to the asymmetry of energy transfer. Discussion shows that this asymmetry exists in a particular range of temperatures, and increases with the increase of the difference between heat baths and the inductance gradient. (fundamental areas of phenomenology(including applications))

Fabrication and characterization of aluminum airbridges for superconducting microwave circuits

International Nuclear Information System (INIS)

Chen, Zijun; Kelly, J.; Barends, R.; Bochmann, J.; Chen, Yu; Chiaro, B.; Dunsworth, A.; Jeffrey, E.; Mutus, J. Y.; O'Malley, P. J. J.; Neill, C.; Roushan, P.; Sank, D.; Vainsencher, A.; Wenner, J.; White, T. C.; Megrant, A.; Cleland, A. N.; Martinis, John M.

2014-01-01

Superconducting microwave circuits based on coplanar waveguides (CPW) are susceptible to parasitic slotline modes which can lead to loss and decoherence. We motivate the use of superconducting airbridges as a reliable method for preventing the propagation of these modes. We describe the fabrication of these airbridges on superconducting resonators, which we use to measure the loss due to placing airbridges over CPW lines. We find that the additional loss at single photon levels is small, and decreases at higher drive powers