Quenched Resistance Effects on a Superconducting Current-Limiting-Type DC Breaker

Application of a dc circuit breaker (DCCB) using superconducting current-limiting technology can strongly reduce the short-circuit currents that occur in high-voltage dc systems. The superconducting current-limiting-type DCCB includes a superconducting current-limiting module and an interrupter module (IM). The objective of this paper is to determine the effects of the quenched resistance characteristics of the superconductor on dc interruption based on the self-excited oscillation principle. We test the quenched resistance characteristics and the recovery times of two different types of YBCO-coated conductor tapes (with critical currents of 102 and 225 A). The quenched resistance of the 102-A YBCO tape was quenched more rapidly than the 225-A tape, and the quenched resistance of the 102-A tape was higher than that of the 225-A tape. Therefore, the 102-A tape can limit the fault current to a lower level, which results in the reduction in the difficulty of interruption for the IM. The arcing time, the absorbed energy, and the peak current in the ZnO arrester of the IM can also be reduced considerably because the interrupting current is much lower.