A New Topology of Hybrid DC Circuit Breaker with Current Limiting Capability

Abstract:
DC circuit breakers and fault current limiters are important devices in DC power grids. They have similar structures and therefore have the conditions for integration. However, most of the existing DC circuit breakers with current limiting capability have complex structures and control strategies. In this regard, this paper proposes a new topology of hybrid DC circuit breaker with current limiting capability, which has simple topology and control strategy. After a fault occurs, the inductor can be inserted for fault current limiting, and the current limiting effect is significant. In addition, the proposed circuit breaker can automatically adjust the working status according to the protection judgment result. This paper first introduces its topology and working principle, then conducts theoretical derivation, and finally performs simulation verification in PSCAD/EMTDC. The simulation results show that the proposed circuit breaker shows good applicability in the DC grid.