Research on All-Solid-State DC Circuit Breaker with Active Fault Current-limiting Circuit

The existing limiting circuits of all-solid-state DC circuit breakers have the problems of large on-state loss and low sensitivity. Based on the change of limiting method, an active fault current-limiting circuit is designed. A timing scheme between the input of the current-limiting circuit and the relay protection is provided for the effect of the current-limiting circuit on the relay sensitivity. At the same time, based on the Hefner model, analyzing the operating principle and circuit current variation in the circuit breaker's breaking and closing process. Finally, the application accuracy of the circuit breaker in DC distribution network is verified by simulation modeling and theoretical analysis.