一种逆阻型模块化多电平换流器的改进方案

Improvement Scheme of a Reverse Blocking Modular Multilevel Converter

本文针对一种逆阻型模块化多电平换流器(Reverse Blocking Modular Multilevel Converter, RB-MMC)提出了改进方案,在该方案下,RB-MMC拓扑无需增加任何辅助器件,只需要改变换流器的闭锁脉冲即可实现直流故障电流的自清除。同时,为了避免MMC近端金属性短路故障时可能出现的交流断路器保护动作,提出了在换流器桥臂串入模块化电阻的方案。最后,基于PSCAD/EMTDC仿真验证了所提方案的正确性和有效性。

In this paper, an improved scheme for reverse blocking modular multilevel converter is proposed. In this scheme, the RB-MMC topology without adding any auxiliary devices, only needs to change the blocking pulse of the converter to realize the self-clearing of the DC fault current. At the same time, in order to avoid the AC breaker protection action which may appear in the MMC near end metal short circuit fault, the scheme of series modular resistance in converter bridge arm is put forward. Finally, the correctness and effectiveness of the proposed scheme is verified by PSCAD/ EMTDC simulation.