基于面积等效法的模块化多电平换流器损耗分析

基于模块化多电平换流器的直流输电(modularmultilevel converter based HVDC,MMC-HVDC)阀的损耗研究目前还没有。由于MMC阀拓扑的特殊性,传统晶闸管和绝缘栅双极晶体管串联阀换流器的损耗计算方法均不能直接应用,文章结合其子模块特有的半导体器件的开关特性,分析了MMC子模块投入和切除的具体物理过程;结合换流器拓扑结构和面积等效调制算法,推导了典型工况下MMC阀的损耗与阀电压、电流、调制算法的关系,为MMC-HVDC输电系统的降损设计提供了依据。

Loss Evaluation for Modular Multilevel Converter Based on Equivalent-Aera Modulation

The result of the research on the loss of the modular multilevel converter(MMC) based valve for HVDC power transmission is seldom reported.Due the distinctive feature of MMC topology,the methods to calculation the loss of traditional loss calculation methods for thyristors and insulate gate bipolar transistors(IGBT) cannot be directly applied to MMC valve.Combining with the switching characteristic of the distinctive semiconductor devices of the sub-module of MMC valve,the physical process of switching on/off the sub-module of MMC valve is analyzed;considering the topological structure of the converter and equivalent-area modulation algorithm,the relation among the loss of MMC valve and its valve current,and modulation algorithm voltage under typical operating condition is derived.The research result is available for reference to the loss reduction design for MMC-HVDC transmission systems.