A topology of the multi-port DC circuit breaker for multi-terminal DC system fault protection

Hybrid DC circuit breaker, a combination of disconnector and multiple power electronic devices, has gained popularity for its low-loss at normal operation and its quick and effective circuit breaking during fault protection. However, its bulkiness threatens to limit its application in multi-terminal DC system, where the terminal is usually connected to more than one transmission lines and hence the circuit breaker tends to appear in clusters. In this context, a multi-port DC circuit breaker topology is proposed here. The circuit breakers at one terminal is integrated into one. Through this, it is able to cut down by half the number of power electronic devices needed, greatly reducing the size and cost for circuit breaking. The effectiveness of the proposed topology is verified by simulation results.