Topology of current-limiting and energy-transferring DC circuit breaker for DC distribution networks

With the development of power electronic technologies and distributed power generation, DC distribution networks attract increasing attention due to their various advantages compared with traditional AC distribution networks. However, DC fault protection is one of the major issues in DC distribution networks. To improve their reliability and protect the semiconductor devices under DC faults, a current-limiting and energy-transferring DC circuit breaker topology is proposed in this paper. By applying passive components and thyristors, the proposed topology is capable of quickly limiting the fault current and transferring the faulty energy. The working principle, mathematical model and parameter designing method of the proposed topology are presented in this paper. The simulation results verify that the proposed DC circuit breaker could effectively limit the fault current and quickly interrupt the fault current. Cost and conduction power loss evaluation proves the practicality of the proposed topology in medium-voltage DC distribution networks.