基于模块化多电平变换器的中压变速驱动器低速与启动运行协调策略

The low-frequency fluctuation over the capacitor voltages seriously limits the development of medium-voltage variable-speed drives with a modular multilevel converter (MMC). Therefore, this paper presents an effective strategy of the low-speed and start-up operation for an MMC-based motor drive. The proposed strategy properly coordinates the improved injection and the reduced average capacitor vol...