Protection scheme based on resistive current-limiting for direct current distribution network inter-pole short-circuit

Aiming at the problems of a large-scale power failure and the slow recovery of the system which caused by converter block in the case of inter-pole short circuit in DC distribution network, this paper proposes a short-circuit protection scheme of inter-pole short circuit in DC distribution network based on fault current limiting module and DC circuit breaker (DCCB). Based on resistive current limiting topology by analyzing the bridge arm current of the converter and the transient characteristics of the DC side fault current, and combining the performance parameters of the converter IGBT, diode devices, and DCCB, we give the theoretical calculation method and selection principle of the resistance parameters. The proposed protection scheme can realize the fault ride-through of the converter during the DC inter-pole short circuit, which reduces the outage scope, lower the requirements of DCCB operation time and opening capacity, and shorten the system recovery time. Simulation results in the PSCAD/EMTDC environment combined with actual engineering parameters verify the correctness and feasibility of the protection scheme.