Thermal and magnetic characteristics of bulk superconductor and performance analysis of magnetic shielding type of superconducting fault current limiter

Superconducting fault current limiter (SCFCL) is expected to be the first application of a high-temperature superconductor (HTS) to electric power systems. The authors have been developing a magnetic shielding type of SCFCL that uses a cylindrical Bi-2223 HTS bulk. Short-circuit fault tests in a small SCFCL model were performed experimentally. A computer program based on the finite element method (FEM) taking the voltage-current (E-J) characteristics of the bulk material into account was developed to analyze the performance in the short-circuit fault tests and to investigate the dynamic electromagnetic behavior within a bulk superconductor. Because the E-J characteristic of HTS bulk depends on temperature and magnetic field, they investigated experimentally the E-J characteristics of a bulk superconductor in various operating temperatures and magnetic fields. The computer program considering the measured E-J characteristics simulated the electromagnetic behaviors in an SCFCL test model successfully (BiPb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub 10/.