MMC子模块元件短路故障机理及其新型保护策略.PDF

2015 年 2 月 电 工 技 术 学 报 Vol.30 No. 3 第 30 卷第 3 期 TRANSACTIONS OF CHINA ELECTROTECHNICAL SOCIETY Feb. 2015 MMC子模块元件短路故障机理及其 新型保护策略 1 1 2 敬华兵 年晓红 龚 芬 （1. 中南大学信息科学与工程学院 长沙 410004 2. 南车株洲电力机车研究所 株洲 412001 ） 摘要 介绍了基于模块化多电平换流器（MMC ）子模块的主电路和控制方式，在分析子模块 故障机理的基础上，提出了器件选型的技术要求，计算了元器件短路保护动作时间，讨论了VT 1 元件故障短路时应对的保护策略，提出了一种在原MMC子模块电路拓扑上增加反向晶闸管的新型 保护策略以限制故障范围，并可取代旁路机械开关。PSCAD仿真结果验证了该保护策略的正确性， 新增的反向晶闸管对保护及时性和有效性具有重要作用。 关键词：模块化多电平换流器子模块 故障机理 保护策略 时序 反向晶闸管 短路击穿 中图分类号：TM73 Fault Mechanism and Novel Protection Strategy of MMC Sub-Module Component Short-Circuit Jing Huabing 1 Nian Xiaohong 1 Gong Fen2 （1. Central South University Changsha 410004 China 2. CSR Electric Locomotive Research Institute Zhuzhou 412001 China ） Abstract The main circuit and control mode of sub-module(SM) based on modular multilevel converter(MMC) are introduced. On the basis of the fault mechanism, the technical requirements of element was proposed ，and the short-circuit protection action time is calculated too. Through discussing the protection strategy for VT 1 short-circuit fault, a novel protection strategy with added SCR in the original circuit topology of SM is put forward to ensure the scope of fault controllable, and the mechanical switch would be replaced with it. Finally, the correctness of protection strategy is indicated by PSCAD simulation, and the added reversed SCR is important to the timeliness and effectiveness of the protection. Keywords ：MMC s