DC circuit breaker is the key equipment to ensure the sound and reliable operation of VSC-based DC grids. To reduce the withstand voltage requirements of pre-charge system, the hybrid DC circuit breaker (HDCB) based on coupled negative voltage commutation needs to be equipped with additional commutation AC transformer, which seriously restricts its application in HVDC transmission. To solve this problem, an HDCB commutated by the controllable active oscillation circuit (CAOC-HDCB) is proposed in this paper. On the premise of guaranteeing the bi...
