一种具备直流故障清除能力的新型MMC子模块拓扑  

Novel MMC sub-module topology with DC fault clearing capability

作　　者：束洪春[1] 王文韬 江耀曦[2] 邵宗学 王锐 廖孟黎 SHU Hongchun;WANG Wentao;JIANG Yaoxi;SHAO Zongxue;WANG Rui;LIAO Mengli(Faculty of Electric Power Engineering,Kunming University of Science and Technology,Kunming 650500,China;Faculty of Information Engineering and Automation,Kunming University of Science and Technology,Kunming 650500,China)

机构地区：[1]昆明理工大学电力工程学院,云南昆明650500 [2]昆明理工大学信息工程与自动化学院,云南昆明650500

出　　处：《电力自动化设备》2022年第5期75-81,共7页Electric Power Automation Equipment

基　　金：国家自然科学基金资助项目(52037003);云南省重大科技专项计划(202002AF080001)。

摘　　要：当基于模块化多电平换流器(MMC)的高压直流输电(MMC-HVDC)系统直流线路发生短路故障时,传统半桥子模块存在无法通过闭锁阻断直流故障电流的问题。对此,提出一种具备直流故障清除能力的基于半桥的五电平新型子模块(FLHBSM)拓扑。FLHBSM与传统半桥子模块具有相同的控制结构,并具备了直流故障清除能力。相比其他具备直流故障清除能力的子模块拓扑,FLHBSM减少了开关器件的数量以及换流站占地面积,降低了损耗,且其控制灵活度高,在提高了MMC经济性的同时增强了其运行可靠性。同时,FLHBSM可以较好地兼容适用于半桥子模块的电容均压策略,并可根据实际需要在均压方案中择优。在MATLAB/Simulink仿真平台搭建了基于FLHBSM的双端±100 kV 21电平MMC-HVDC系统仿真模型,验证了其利用子模块闭锁模式清除直流故障的有效性。When short circuit fault occurs on DC line of MMC-HVDC(High Voltage Direct Circuit based on Modular Multilevel Converter) system,the DC fault current cannot be blocked by traditional HBSM(HalfBridge Sub-Module). In this regard,a FLHBSM(novel Five-Level Half-Bridge Sub-Module) topology is proposed. FLHBSM has the same control structure as HBSM with the addition of DC fault clearing capability.Compared with other sub-module topologies with DC fault clearing capability,FLHBSM reduces the number of switching devices and the area occupied by the converter station,reduces the loss and provides high control flexibility,and not only improves the economy of MMC,but also enhances its operation reliability.Meanwhile,FLHBSM can be compatible with the capacitor voltage balancing strategies suitable for HBSM,and can choose better capacitor voltage balancing strategy according to the actual needs. A simulation model of bi-terminal ±100 kV 21-level MMC-HVDC system based on FLHBSM is built on MATLAB/Simulink platform,which verifies the effectiveness of DC fault clearing capacity by using FLHBSM.

关 键 词：MMC 子模块拓扑 直流故障清除能力 均压策略 经济性 

分 类 号：TM46[电气工程—电器]