Development of the superconducting transformer is arguably the most difficult of the ac power applications of superconductivity - this is because of the need for very low ac losses, adequate fault and surge performance, and the rigors of the application e...

... Abstract : The theory of magnetohydrodynamic power generators is presented. ... sectional area flows; end losses; AC generation; cycle efficiencies ...

The objective of the study is to estimate the probability of failure of the battery system of a nuclear power plant due to loss of ventilation in the battery room during AC blackout. This is part of the more general problem of the interaction between non-...

The objective of the program was to study the feasibility of Nb3Ge being used as an AC superconducting power transmission cable material. Specifically, the program was to measure AC losses in available samples of Nb3Ge and find under what conditions the l...

In order to apply widely the superconductivity technology to electric power equipments, the development and evaluation on the AC superconducting cables have been conducted in the Central Research Institute of Electric Power Industry. The superconducting c...

It is recognized that the availability of AC power to commercial nuclear power plants is essential for safe operations and accident recovery. A loss of offsite power (LOSP) event, therefore, is considered an important contributor to total risk at nuclear ...

A power grid is a transmission network transporting electrical energy from power plants to some substations near urban or industrial centers. To reduce the loss ...

... AC Loss Minimisation in High Temperature Superconductors ... Extension to AC Loss Minimisation in High Temperature Superconductors ...

The frequency dependence of magnetic ac loss of thin superconductor strip subjected to an ac magnetic field perpendicular to the surface of the strip is investigated by incorporating a flux creep model into the critical state model of Brandt and Indenbom. It is found that the reduced ac loss ...

The effects of reactor coolant system natural circulation on the response of the Surry Nuclear Power Plant during a station blackout transient were investigated. A TMLB' sequence (loss of all ac power, immediate loss of auxiliary feedwater) was simulated ...

We have manufactured a small circular superconducting coil impregnated with epoxy fibreglass. The coil was wound from a Bi-2223/Ag superconducting wire and it was tested in liquid nitrogen at 77 K. Current-voltage characteristic and the AC losses of the coil were measured and compared with the measurements on the original tape. The AC ...

The thermo-hydraulic analysis of plant response on total loss of AC power is very demanding and challenging job due to a number of phenomena included. Such an analysis becomes even more complicated and interesting if we include also the assumption of tota...

A compact, easy to fabricate, noninductive, low surface magnetic field superconductor transmission line that has minimal stay fields is described.

... electric effect. It was also shown that heat power losses due to the ac- tive element in radiating transducers are dependent upon past thermal, 15 ...

A calorimeter has been developed to measure the total core loss in small samples of magnetic materials which are not suited to conventional measurement techniques. The method is similar to the helium boil-off calorimeter used in some cases to measure ac losses in superconductors. Power losses ...

A calorimeter has been developed to measure the total core loss in small samples of magnetic materials which are not suited to conventional measurement techniques. The method is similar to the helium boil-off calorimeter used in some cases to measure ac losses in superconductors. Power losses ...

A calorimeter for measuring ac losses in meter-long lengths of HTS superconducting power transmission line cables is described. The calorimeter, which is based on a temperature difference technique, has a precision of 1 mW and measures single, two-phase (coupling), and three-phase losses. The measurements show ...

Results are given for the permeability, conductivity, and dielectric constant of a multifilament superconductor, treated as an anisotropic state of matter. The calculations are made for the limiting cases of strong and weak ac magnetic fields compared with the field required for complete penetration of the filaments. General expressions are given for the ...

The authors report single-phase ac loss measurements on 8, 4, and 3-layer, multi-strand, HTS prototype conductors for power transmission lines. They use both calorimetric and electrical techniques. The agreement between the two techniques suggests that the interlayer current distribution in one-meter long conductors are representative ...

This report discusses the AC losses in the MICE channel magnets during magnet charging and discharging. This report talks about the three types of AC losses in the MICE magnets; the hysteretic AC loss in the superconductor, the coupling AC ...

The successful application of superconductivity to motors and other power system components depends on the characterization and subsequent minimization of the ac loss in the superconductor used for fabrication of the component. The superconductive component, excited by an ac power source, may ...

Station blackout is the complete loss of alternating current (ac) electric power to the essential and nonessential buses in a nuclear power plant; it results when both offsite power and the onsite emergency ac power systems are unavailable. Because many ...

Superconductors with inhomogeneous or filamentary structures are able to carry current distributed right across their cross sections. Because of flux- trapping properties, the form of current distribution will in general depend on the previous history of the specimen and, if a-c are carried, hysteresis in the current distribution is to be expected. This is equivalent ...

Emergency onsite ac power systems at nuclear power plants are a major concern in plant risk assessments because of the relatively large frequency of loss of offsite power and the dependence of most other safety systems on ac power. Detailed reviews of ...

Techniques for energy conservation of reducing losses in ac motor driven systems were compared. The impact on electric utility system as a harmonics, power factor of operation, and Electro Magnetic Interference (EMI) is considered. The techniques evaluated are: (1) the NASA Power Factor Controller, a simple device ...

This paper presents and discusses techniques for energy conservation by reducing losses in ac motor driven systems, proposed by the technical community in response to surging cost of energy. An important aspect considered is the impact on electric utility systems in terms of harmonics and power factor of operation. The techniques ...

For the design of a high temperature superconductor (HTS) power transformer the AC loss is a critical issue because the energy is dissipated as heat in the low temperature. It is necessary to study the AC losses theoretically and experimentally. For the analysis of AC ...

We investigate the AC loss of a high-0953-2048/10/8/004/img2 superconducting power-cable conductor with four layers and interlayer insulation. The electric-circuit model is applied for the calculation of the AC loss of the conductor. The result of a calculation for the AC ...

Power cables are one of the most promising applications for the superconducting coated conductors. In the AC use, only small resistive loss is generated, but the removal of the dissipated heat from the cryostat is inefficient due to the large temperature difference. The aim of this work is to minimize the AC ...

The status of attempts and techniques to reduce audible noise and corona generation and losses in EHV AC overhead power transmission lines in general is reviewed. A number of other promising concepts are identified. The correspondence between available au...

''Station Blackout,'' which is the complete loss of alternating current (AC) electrical power in a nuclear power plant, has been designated as Unresolved Safety Issue A-44. Because many safety systems required for reactor core decay heat removal and containment heat removal ...

A site area emergency at the Vogtle Unit 2 Nuclear Power Plant is described in some detail. The incident involved loss of all offsite and onsite ac power for more than 15 minutes. Plant status prior to the incident, actions taken to restore power, and preliminary investigation of causes are ...

... YBCO Coated Conductors with Reduced AC Losses ... YBCO Coated Conductor, AC losses, RABiTS, Superconductor, Maganetic Properties ...

... Extension to AC Loss Minimisation in High Temperature Superconductors ... The transport AC loss decreases more than 3 times. ...

AFRL-PR-WP-TP-2006-208 AC LOSS REDUCTION OF YBCO ... SUBJECT TERMS AC losses, coated conductors, YBCO, multifilamentary 16. ...

Formulae are presented for the eddy current AC power loss and the AC hysteresis loss of z-stacks and x-arrays made of metal-superconductor strips. The AC self-field case and the applied AC magnetic field case are examined for different stacking spacings ...

Sep 3, 2010 ... SUBTOPIC TITLE: Power Management and Storage. PROPOSAL TITLE: Efficient Lightweight AC-AC Power Control for Solar UAV ...

The effects of metallurgical processing on 60 Hz ac losses and dc critical currents in Nb/sub 3/Sn tapes fabricated by the solid state diffusion technique were investigated. An addition of Al to the Cu--Sn alloy for the matrix resulted in large reduction in the ac losses of Nb/sub 3/Sn tapes, but the highest linear ...

The effects of metallurgical processing on 60 Hz ac losses and dc critical currents in Nb/sub 3/Sn tapes fabricated by the solid state diffusion technique were investigated. An addition to Al to the Cu-Sn alloy for the matrix resulted in large reduction in the ac losses of Nb/sub 3/Sn tapes, but the highest linear ...

Self-field ac losses were measured by the conventional ac four-probe method in biaxially aligned Y{endash}Ba{endash}Cu{endash}O tapes using polycrystalline Hastelloy tapes with textured yttria-stabilized-zirconia buffer layers. The ac losses increased in proportion to the fourth ...

Results are presented of an investigation to develop a 500 kV ac laminar dielectric power cable and joint having insulation with lower losses than conventional cellulosic paper insulation. Background information is presented on proposed low-loss synthetic...

AC losses in high-temperature superconductors are modelled as a highly non-linear diffusion process. Two empirical expressions for modelling effective resistivity of the conductor are used. Formulations in terms of both H and E are presented and it is argued, using dimensional analysis, that working with E is numerically more efficient. Typical results ...

The results of an investigation to develop a 500 kV ac laminar dielectric power cable and joint having insulation with lower losses than conventional cellulosic paper insulation are presented. Background information is presented on proposed low-loss synth...

Samples of heavily worked, cold-drawn niobium wire were heattreated at temperatures between 200 and 700 deg C to produce changes in the magnetization behavior of the material. An investigation was then carried out to determine the influence of these changes on the AC power losses produced in the wires at 4.2 K due to 50 Hz ...

... Abstract : Results are presented on the AC and DC characteristics of Wausau granite which show that excess AC losses at low temperatures are ...

The objective of the program was to study the feasibility of Nb/sub 3/Ge being used as an AC superconducting power transmission cable material. Specifically, the program was to measure AC losses in available samples of Nb/sub 3/Ge and find under what conditions the losses can be reduced to 10 ...

This paper investigates the electromagnetic properties of high-temperature superconductors with a particular focus on the AC loss in coils made from YBCO superconductors. The numerical analysis and finite element modelling of the YBCO superconductors used in Cambridge�s superconducting permanent magnet synchronous motor currently in development is ...

In order to research the AC loss characteristics of a multi-layered conductor and a shield in a high temperature superconductor (HTS) cable, we prepared two short cable samples, which are the same as the 22.9 kV/50 MVA HTS-cable installed at Gochang test yard of Korea Electric Power Corporation, and attached voltage-leads to both the ...

This paper is devoted to predict AC loss of cable in conduit conductor (CICC) which is of importance in the design of conductors. The consideration for the conductor's design and main parameters for the magnets are introduced. In order to attain a good accuracy in the calculation of AC losses, the field ...

In this paper we investigate the effectiveness of an alternative design scheme to reduce the AC losses in high temperature superconducting (HTS) power transmission cables made of non-ferromagnetic HTS coated conductors. With this design, the adjacent tapes of each layer of the cable overlap each other up to a certain distance from ...

This paper proposes a new magnetic levitation scheme which is able to generate levitation force for all speeds including a standstill. Auxiliary wheels which are needed in EDS MAGLEV vehicle can be eliminated. This scheme uses AC superconducting magnets to generate levitation force. In this paper, magnetic fields, forces and power dissipations generated by ...

As a candidate for a low ac-loss bulk power transmission cable, a high-{ital T}{sub {ital c}} superconducting wire in a flux-flow state, which is called a {ital flux}-{ital flow} {ital superconductor} here, is theoretically studied. The electrodynamics of such a wire in a self-excited ac field is formulated, where the governing ...

Significant advances in modern ac/ac power converter technologies and demands of industries have reached beyond standard ac/ac power converters with voltage-source inverters fed from diode rectifiers. Power electronics converters have been matured to stages toward compact realization, increased ...

Reducing AC loss in a superconducting apparatus is one of the most important issues, and the precise measurement and estimation of AC losses are essential to reduce them. The four-terminal method is universally used as an electric measurement method of AC losses for ...

... Accession Number : ADA461815. Title : AC Loss Reduction of YBCO Coated Conductors by Multifilamentary Structure. Descriptive ...

... Title : AC LOSSES OF SUPERCONDUCTING COMPOSITES WITH 8 MU-M NBTI FILAMENTS IN A DC MAGNETIC FIELD WITH A ...

A loss of ac power to the station occurred on July 28, 1978 caused by an interaction between Beaver Valley Power Station and Shippingport Atomic Power Station when the main transformer of Unit No. 1 of the Beaver Valley Power Station developed an internal...

The frequency-dependent critical current of a superconductor strip and Roebel cable has been studied using a 2D finite element simulation. It is shown that the critical current of the superconductor increases with frequency as f1/n, where n is the exponent of the power law flux creep model. Transport ac loss in a superconductor strip ...

The winding technology with high current capacity is one of the important factors in power application of 20 MVA/66 kV-class superconducting power transformers. High-current power transformer is achieved by transposed conductors made of Rare Earth-based superconducting coated conductors. By transpositions, the improvement of uniformity ...

While considerable work has been done to understand AC losses in power cables made of first generation (1G) high temperature superconductor (HTS) wires, use of second generation (2G) HTS wires brings in some new considerations. The high critical current density of the HTS layer 2G wire reduces the surface superconductor hysteretic ...

This report presents the results of a review of the Auxiliary Feedwater System Reliability Analysis for Catawba Units 1 and 2. The objective of this report is to estimate the probability that the Auxiliary Feedwater System will fail to perform its mission for each of three different initiators: (1) loss of main feedwater with offsite power available, (2) ...

Power engineering applications of HTSC tapes are often restricted by AC losses. Both direct and indirect methods have been used to measure AC losses in short samples. This paper reports on the development of a direct calorimetric method for AC loss ...

This report presents test data recorded for Tests S-PL-1, -2, and -3 of the Semiscale Mod-2B Power Loss (PL) Test Series. These tests are the first of a series of Semiscale tests that represent a broad spectrum of offsite ac power loss transients ranging from an offsite ...

Some of PWR severe accidents are initiated by loss of all AC power. In these cases, accident would proceed while the primary system pressure is still at high level. Thus it is proposed that an intentional depressurization of the primary system has a poten...

The power supply design of the (gamma)(sub f) - jump system in FNAL Main Injector uses a resonant circuit. A critical design parameter is the ac losses of the beam tube in a pulsed quadrupole. This paper gives an analysis to this problem. An equivalent ci...

We have measured energy loss of 0.5-2 MeV 4He ions in Mylar and Kapton foil, and hydrogenated amorphous carbon (a-C : H) films. The energy loss values or stopping powers are in good agreement with the calculation from Ziegler's cores and bonds (CAB) stopping model. No significant physical state (gas-solid) effect ...

A superconducting cable incorporating Nb/sub 3/Sn is briefly described and requirements for the superconductor discussed. State of the art metallurgical procedures for reducing ac losses and increasing critical currents of Nb/sub 3/Sn are reviewed. The loss behavior is then related to presently available theoretical models and shown to ...

A simple way to obtain true ac losses with a resonant circuit containing a superconductor, using the decay of the circuit current, is described. For the measurement a capacitor is short circuited with a superconducting cable. Energy in the circuit is provided by either charging up the capacitors with a certain voltage, or letting a dc flow in the ...

A two-dimensional numerical diffusion model which estimates self-field ac losses in High-Tc Superconducting (HTS) tapes is developed. The HTS tape is simulated as a nonlinear conductor whose equivalent resistivity is derived from a power law E-J characteristic. Results of various field quantities and ac ...

We have calculated the alternating current (ac) losses of a 114 MVA high-TC superconducting (HTS) transmission cable using an electric-circuit (EC) model. The HTS cable is fabricated by Tokyo Electric Power Company and Sumitomo Electric Industries, Ltd. The EC model is comprised of a resistive part and an inductive part. The resistive ...

This report presents the results of the review of the Auxiliary Feedwater System reliability analysis for the Vogtle Electric Generating Plant (VEGP) Units 1 and 2. The objective of this report is to estimate the probability that the Auxiliary Feedwater System will fail to perform its mission for each of three different initiators: (1) loss of main feedwater with offsite ...

The authors discuss how nuclear plants in the United States have taken actions to respond to the NRC Station Blackout Rule, 10CFR50.63. The rule requires that each light water cooled nuclear power plant licensed to operate must be able to withstand for a specified duration and recover from a station blackout. Station blackout is defined as the complete ...

A simple model gave utilized for calculation of magnetization effects on ac loss and sextupole for Energy Doubler dipole magnets. The calculation in the simple model gave an underestimation of ac loss by about 30%. Results of computation on ac harmonics were also described.

The AC magnetic losses at power frequencies (60 Hz) were investigated for mono- and multifilament Ag-sheathed (Bi, Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub y} (BSCCO-2223) tapes with similar transport critical current (I{sub c}) values at 77 K. The multifilament sample exhibited higher losses than the ...

In particle accelerators quasi-DC superconducting magnets are used to keep particles in desired tracks. The needed rapid field variations of these high energy magnets require large energy bursts. If these bursts are taken from and fed back to the utility grid, its voltage is distorted and the quality of the electricity degrades. In addition, these bursts may decrease operation life time of ...

monitor and power supply data, such as beam loss during magnet quenches, dump kicker misfires and power Current Xfmr AC Line Monitor Power Supply quench quench dump beamabort dump beamabort Data storage for mortem plots show voltage ripples for many of the supplies, throughout the ring. ...

A system is presented to aid in correcting a low power factor to increase a plant's AC capacity. This is also an aid to reducing ''penalty'' charges, improving voltage supply, and lowering power loss in feeders, transformers, and distribution equipment. A worksheet is ...

Eastham and Rhodes published results of loss measurements on transposed superconducting NbTi cables and concluded basing on an extrapolation to very large numbers of wires that transposed superconductors could be used favorably in cables for power transmission. There are some reasons to question the correctness of their extrapolation. ...

A method is described for calorimetric ac-loss measurements of high-T(c) superconductors (HTS) at 80 K. It is based on a technique used at 4.2 K for conventional superconducting wires that allows an easy loss measurement in parallel or perpendicular external field orientation. This paper focuses on ac loss ...

A method is described for calorimetric ac-loss measurements of high-Tc superconductors (HTS) at 80 K. It is based on a technique used at 4.2 K for conventional superconducting wires that allows an easy loss measurement in parallel or perpendicular external field orientation. This paper focuses on ac loss ...

AC losses in two, one-meter-long lengths of HTS prototype multi-strand conductors (PMC`s) are measured with a temperature-difference calorimeter. Both single-phase and three-phase losses are examined with ac currents up to 1,000 A rms. The calorimeter, designed specifically for these measurements, has a precision ...

Page 1. EFFECT OF AC POWER ON EBW DETONATORS Allan H. Herrbach ... 4. TITLE AND SUBTITLE Effect of AC Power on EBW Detonators 5a. ...

Efficient, light-weight power conditioning equipment was investigated in the area of AC to AC transformation, where AC of a variable frequency is to be transformed efficiently into AC of a fixed frequency at a significant power level. This task, which fol...

Researches and developments on a superconducting fault current limiting (SFCL) system have been done for several decades. The SFCL system, which is using a high temperature superconducting (HTS) conductor such as Bi-2212 bulk and YBCO film, has recently become technically available. In this work, we are developing a 22.9 kV/25 MVA SFCL system for a power distribution network. ...

A study has been made of ac loss characteristics of type-II superconductors due to hysteresis losses in the superconducting material and eddy current losses in the normal matrix in the absence of an applied field. Losses were measured for Nb$sub 3$Sn tapes, a Nb multifilament conductor, ...

This paper described the survey and view of present R . D status of high T (sub c) superconductors for AC applications. It is necessary to reduce the AC loss for wire but high T (sub c) superconductors which are different from low-T (sub c) ones, exhibit ...

The experimental studies performed under this contract comprised investigation of two principal approaches to achieving very low levels of ac loss in Nb sub 3 Sn produced by the liquid diffusion process. These approaches were inhibition of the formation o...

A single active element performs the multiple functions of regulating dc voltage level from an ac source supplied to charge a battery and of coupling the battery to power an emergency system such as an emergency lighting system upon loss of the ac source. Preferably, the single active element also performs a third ...

In this study, we focus on the examination of ac losses in conductors utilizing Bi{sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O [BSCCO (2223)] high TC superconductors (HTS). In addition, we seek to assist other facilities such as the University of Wisconsin-Madison Applied Superconductivity Center (UW-ASC), Brookhaven National Laboratory, and other DoE facilities ...

A large amount of power (5 GW or more) can be transmitted through a dc superconducting power transmission line (SPTL) which has the highest power density and efficiency of any known transmission line. Although the SPTL has zero resistance to pure dc, it experiences hysteresis and resistive losses under ...

For near-future applications of REBa2Cu3O7 (REBCO) coated conductors to electric power cables, transformers and Superconducting Magnetic Energy Storage (SMES), the long taped wires with high performance in the transport properties have been designed and fabricated. Moreover, in order to drastically reduce AC losses in perpendicular ...

Techniques for energy conservation of reducing losses in ac motor-driven systems proposed by the technical community in response to surging cost of energy are evaluated and compared. Report objectives are to provide better understanding of underlying principles and to evaluate technical and economic viability of these techniques for various applications. ...

We have developed the technology of the producing a HTS magnet for the power transformer. Three subjects have been mainly studied, high voltage technologies, large current and low AC loss technologies and sub-cooling system technologies to establish the technology of 66 kV/6.9 kV 10 MV A class HTS power ...

Superconducting transmission cables are important for increasing the capability of electricity networks. We analysed monolayer power transmission cable based on high-temperature superconductors, and we propose a new way to improve its performance in this paper. We studied two important parameters of this cable�critical current and AC ...