基于分裂电感的限流式MMC-UPFC

Current-limiting MMC-UPFC based on split inductor

为了降低交流系统短路故障给基于模块化多电平换流器的统一潮流控制器(MMC-UPFC)带来的大电流冲击风险,保障电力电子设备的安全运行,提出了一种基于分裂电感的限流式MMC-UPFC。通过对桥臂电感的分裂设计和串联变压器阀侧晶闸管旁路开关空间配置的调整,实现换流器的快速保护和故障电流的有效限制。详细地阐述了该拓扑结构的限流原理,并进行了关键参数的优化设计。通过PSCAD/EMTDC软件对所提限流式MMC-UPFC拓扑结构进行建模仿真与分析,仿真结果证明了该拓扑结构具有灵活的潮流调节特性和显著的故障限流能力。

In order to reduce the risk of large-current shocks caused by AC system short circuit faults to MMC-UPFC(Unified Power Flow Controller based on Modular Multilevel Converter)and ensure the safe operation of power electronic equipment,a novel current-limiting UPFC-MMC topology based on split inductors is proposed. Through the split design of the bridge arm inductance and the space configuration adjustment of the thyristor bypass switch on the valve side of the series transformer,the fast protection of the converter and the effective limitation of the fault current are realized. The current-limiting principle of this topolo? gy is elaborated,and the optimization design of key parameters is carried out. The simulation and analysis of proposed current-limit MMC-UPFC topology are carried out by PSCAD/EMTDC. The simulative results show that proposed topology has flexible power flow regulation characteristics and significant fault current limiting capability.