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提出了一种模块化多电平换流器(module multilevel converter,MMC)子模块电容电压预测均衡控制的混合控制方法.根据子模块工作状态和换流器桥臂电流大小,得到下一动作周期子模块电容电压的预测值;以预测的电容电压绝对误差限值作为电压偏差量判据,得到下一动作周期的子模块投切方案.该方法保证了子模块电容电压的均衡性,同时有效降低了功率器件的开关频率.在PSCAD/EMTDC上构建了11电平MMC系统,仿真结果验证了所提方法的有效性.“,”A hybrid control method for balance control of the sub-module capacitor voltage based on multi-level converter module (MMC) is proposed.According to state of the sub module and current of the converter bridge,the predictive value of the sub-modules capacitor voltage in the next action cycle is obtained.Taking the predictive absolute error limit of the capacitor voltage as the voltage deviation criterion,the sub-modules switching on/off scheme for the next action cycle is obtained.Proposed method can guarantee the balance of sub-modules capacitor voltage as well as the low switching frequency.In the end,11-level MMC system is built in the PSCAD / EMTDC,and the simulation results verify the effectiveness of the proposed method.