Current Limiting Performance of Transformer-Type Superconducting Fault Current Limiter Made of BSCCO and REBCO Wires

Superconducting fault current limiters (SFCLs) are expected to be installed in the power system for fault current limitation and improvement of power system stability. Among various SFCLs, we have proposed the transformer-type SFCL that produces limiting reactance for smaller fault currents and, additionally, gives limiting resistance for larger fault currents. Therefore, the transformer-type SFCL shows better recovery performance than resistive-type SFCLs. In this paper, we fabricated two transformer-type SFCLs using different high-temperature superconducting wires [Bi-2223 (BSCCO) wire and GdBCO, which is a kind of rare-earth-barium-copper-oxide (REBCO) wire] for the secondary coils and compared their current limiting characteristics. They were designed under the condition that the specifications of the primary coils and their trigger current level are about the same, respectively. As a result of comparing their current limiting characteristics, the transformer-type SFCL using GdBCO wire for the secondary coil shows a larger limiting reactance and dissipates less energy. Therefore, the transformer-type SFCL using GdBCO wire for the secondary coil shows better recovery performance.