具备限流能力的混合式高压直流断路器拓扑OA北大核心CSTPCD

DC circuit breaker(DCCB)is an important means to solve the short-circuit fault of DC system.In view of such a series of defects as weak current limiting effect,short operation life of arrester and slow fault isolation speed of the existing DCCB,a kind of hybrid high-voltage DC circuit breaker topology solution with current limiting capa-bility(CLC-HDCCB)is proposed in this paper.The CLC-HDCCB current-carrying branch and transfer branch adopt double-bridge structure and possesses bidirectional on-off capability.The current-limiting part adopts current-limit-ing resistor inductor in parallel to limit the current,which significantly reduces the peak value and rise rate of fault current.The designed bleeder resistor bypasses the current-limiting inductance during the circuit breaking process,which reduces the energy absorbed by the arrester in single breaking operation.In addition,various conditions oc-curred in such DC system as breaking fault current,normal closing operation and breaking small current of the CLC-HDCCB scheme is analyzed in detail and also the parameter selection method is given.Finally,the simulation verifi-cation is carried out on the PSCAD/EMTDC platform,and the results show that the proposed CLC-HDCCB scheme has certain advantages compared with the existing DCCB scheme in terms of fault current limiting,arrester energy absorption and fault clearing time.