计及分布参数影响的模块化多电平换流器充电策略优化OA

This paper introduces the structure and charging process of the high-voltage and large-capacity modular multilevel converter(MMC),and analyzes the influence of stray parameters on the charging process.In order to solve the problem of uneven charging voltage of sub-modules in the upper and lower bridge arms under the DC-side charging mode,a voltage difference correction strategy is proposed.The voltage difference between the upper and lower bridge arms is taken as the control target to feedback and adjust the number of charging modules in each bridge arm,which helps the voltage imbalance of the module to decrease from 6.7%to 1%,and solves the problem of module voltage imbalance among each bridge arm during the charging period on the DC side.Hence the paper provides a stable prerequisite for the subsequent modulation and control strategies of the modular multilevel converter so as to ensure the reliable operation of the equipment.