Results 261 to 270 of about 2,262,511 (306)

AC Losses in Hard Superconductors

1963
Fagan[1], McFee[2], and others have suggested the possibility of building transformers, transmission lines, rectifiers, rotating equipment, and other ac power equipment using superconductors. The practicability of many of these devices depends on the feasibility of producing superconductors that will carry high ac current densities at high ac magnetic ...
C. H. Jones, H. L. Schenk
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AC losses in Y1Ba2Cu3O7??:Ag tapes

Journal of Superconductivity, 1993
The frequency dependence of ac losses of a superconducting tape consisting of Y1Ba2Cu3O7-δ material in a silver sheath was measured from 50 Hz to 50 kHz using a four-probe technique developed and reported earlier. Contrary to expectation, the ac losses were found to have a frequency-independent regime in the loss spectrum.
K. N. Mirchandani, Kamal K. Das, Binod Kumar   +2 more
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AC losses in HTSC conductor elements

IEEE Transactions on Appiled Superconductivity, 1992
AC self-field losses and DC dynamic resistivity in HTSC conductor elements have been measured. The data are discussed with reference to the relevant theory. For two very different sample types, the J/sub c/ calculated on the basis of the AC self-field loss is about an order of magnitude lower than the J/sub c/ based on the 1- mu V/cm DC voltage drop ...
S. A. Boggs, E. W. Collings, M. V. Parish   +2 more
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AC losses in composite superconducting wires

Journal of Physics D: Applied Physics, 1970
Measurements have been made at 42 K of the losses in filamentary composites of niobium in copper carrying transport currents of up to 70 A at frequencies in the range 50 to 800 Hz. Critical currents and B-H loops were also measured. The experimental results can be accounted for on the basis of a physical model in which the composite wire behaves as a ...
D R Salmon, J A Catterall
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AC LOSSES OF SUPERCONDUCTING ACCELERATOR MAGNETS

Modern Physics Letters B, 2003
We are focusing on the uncertainties of analytical and numerical analysis of AC losses in superconducting accelerator magnets working at a relatively high ramp rate. The loss experimental techniques are discussed as well as the source of error in the measurements.
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Predicting AC loss in practical superconductors

Superconductor Science and Technology, 2006
Recent progress in the development of methods used to predict AC loss in superconducting conductors is summarized. It is underlined that the loss is just one of the electromagnetic characteristics controlled by the time evolution of magnetic field and current distribution inside the conductor.
F Gömöry, J Šouc, M Vojenčiak, E Seiler, B Klinčok, J M Ceballos, E Pardo, A Sanchez, C Navau, S Farinon, P Fabbricatore   +10 more
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Superconductor coil geometry and ac losses

Journal of Applied Physics, 1976
An empirical relation is presented which allows simple computation of volume-averaged winding fields from central fields for coils of small rectangular cross sections. This relation suggests that, in certain applications, ac-loss minimization can be accomplished by use of low winding densities, provided that hysteresis losses are independent of winding
T. V. Pierce, R. N. Zapata
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ac losses of superconducting solenoidal coils

Journal of Applied Physics, 1982
ac losses of superconducting solenoidal coils were investigated with a calorimetric method while applying a current or uniform magnetic field of 50 Hz with a sinusoidal wave form. The peak value of the ac current was varied from 0 to 15 rms A and that of the ac magnetic field from 0 to 0.02 T.
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AC Loss in High-Tc Superconductors

2000
There are three kinds of AC losses in superconducting wires, transport current losses, magnetization losses and total losses. The first losses are caused by the AC transport currents flowing in the wires, the second caused by the AC external magnetic fields which the wires are subject to and the third caused by the combination of the transport currents
Osami Tsukamoto, Marian Ciszek, Naoyuki Amemiya   +2 more
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Semiconductor power losses in AC inverters

IAS '95. Conference Record of the 1995 IEEE Industry Applications Conference Thirtieth IAS Annual Meeting, 2002
The AC induction motor is the workhorse of modern industry. Worldwide about 50 million motors are installed every year which are greater than 1/2 hp. Three-phase induction motors are very simple and inexpensive to build. An AC motor may be used for variable speed applications with the addition of an AC inverter. An accurate model of semiconductor power
K. Berringer, J. Marvin, P. Perruchoud
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