Hybrid DC Circuit Breaker with Power Flow Control Function

The DC power grid will be an important part of power system with the development of DC load. The DC circuit breaker is the key equipment in DC grid, which can interrupt faulty current but it uses a large number of expensive power electronic components. Meanwhile the DC system needs power flow controller which also applies power electronic components to regulate the line current. The aforementioned two power equipments can share some semiconductor switches to save the construction cost and space. So, this paper proposes a new hybrid DC circuit breaker with power flow control function. First, the topology of new hybrid DC circuit breaker is designed and the fountions of power flow control and fault isolation are analyzed. Then, the parameters and control strategy of power flow control module are presented. Finally, the simulation results based on PSCAD/EMTDC show that the designed DC circuit breaker can validly control power flow and isolate the fault.