A capacitor commutated hybrid DC circuit breaker

DC circuit breaker is the core equipment for cutting out the short circuit fault of DC system. In this paper, a capacitor commutated hybrid DC circuit breaker is proposed that combines the commutation branch with the self-charging branch, reducing the number of branches while ensuring the performance of the circuit breaker. The circuit breaker takes advantage of the symmetry of the commutation branch to break fault currents in both directions, while having the reclosing function. Through the theoretical analysis of the topology structure, the working principle and mathematical model of the circuit breaker at different stages during breaking process are studied, the parameter of key components are designed. Also, a system simulation model is built using simulation software, and the breaking performance of the circuit breaker is verified. Finally, the performance and economy of the circuit breaker are compared with other topology schemes. The results show that the circuit breaker not only has a similar performance, but also can greatly reduce the cost of the equipment, with good economic and application prospects.