一种模块化多电平变流器的环流分析及抑制策略  

A Circulating Current Analysis and Suppressing Strategy of Modular Multilevel Converter

作　　者：于洋[1,2] 葛琼璇[1] 王晓新[1] 张波[1,2] 

机构地区：[1]中国科学院电力电子与电气驱动重点实验室(中国科学院电工研究所),北京100190 [2]中国科学院大学,北京100049

出　　处：《电力电子技术》2016年第8期20-23,共4页Power Electronics

基　　金：国家高技术研究发展计划(863)(2014AA052602)~~

摘　　要：模块化多电平变流器(MMC)因其结构特点带来的环流问题使桥臂电流发生畸变,增加了系统损耗。这里建立了MMC的数学模型,以开关函数为出发点,对环流成分进行分析,并给出了各次谐波解析表达式。为实现环流的有效控制,提出一种基于比例积分(PI)+比例谐振(PR)的复合控制策略,实现了桥臂环流中的2次谐波和4次谐波的有效抑制。最后,仿真和实验结果证明了环流理论推导的正确性和环流抑制策略的可靠性。The circulating current problem of modular multilevel converter（MMC ） because of the structural character- istics leads to the bridge arm current distortion,which increases the system cost.The mathematical model of MMC is established, and the components of circulating current are analyzed in the point of view of the switch function.The analysis shows that the circulating current mainly contains the direct current component and even harmonic components, and the analytical expression of each harmonic is given.In order to realize the effective control of the cir- culating current, a control strategy based on proportional integral （PI） and proportional resonant （PR） controller is pro- posed for the 2nd harmonic and the 4nd harmonic suppression.Finally,the simulation and experimental results demonstrate the correct of the theoretical analysis on the circulating current and the effectively of the control strategy.

关 键 词：变流器 模块化多电平 解耦控制 环流 

分 类 号：TM46[电气工程—电器]