Preparation of high T/sub c/ superconducting coils for consideration of their use in a prototype fault current limiter

High T/sub c/ superconducting coils, made using Ag clad (Bi,Pb)SrCaCuO-2223 wires, have been used for building a small prototype of an electrical transmission system fault current limiter. The techniques for fabricating high T/sub c/ superconducting coils with the Bi-2223 Ag clad long wire are described, which include transferring the long wire to coils and wire-joining techniques to enhance total current ampere-turns of such coils. Testing with these coils includes the magnetic field dependence of its critical current I/sub c/, the mechanical bending property and cracks on the superconductor. The prototype based on the principle of a magnetic core saturable reactor is studied. The results from the superconducting coils and the prototype are helpful for evaluating the application of the high T/sub c/ superconductors in the electrical power system.<
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