Study of IGCT Based Superconducting Hybrid DC Circuit Breakers in Subway DC Traction Power Supply System

DC circuit breaker plays a salient character in the conservation of metro traction power supply system. The crucial point in designing the circuit breaker is to analyze the short circuit characteristics after a fault occurs. This paper presents the construction and features of the subway traction power supply system, establishes the test circuit under faults f, e and d, and analyzes the short-circuit characteristics under the three fault conditions. Lastly, the topology of the IGCT-based superconducting hybrid DC circuit breaker (SDCCB) is described and the fault current interruption characteristics under faults f, e and d are analyzed. The results show that the nearer the short-circuit location is to the rectifier outlet, the higher the peak and rate of climb of the current. And the proposed SDCCB can be successfully interrupted in all three fault cases and normal cases.