中文摘要：

通过分析模块化多电平变换器（modular multilevel converter,MMC）各部分之间的功率关系,提出一种MMC综合控制方案,包括直流母线电压控制和桥臂电容电压控制。该方案内环采用桥臂电流直接反馈控制,可实现交流侧电流、直流母线电流和内部环流的三重控制,不需要专门的环流控制器。该方案各桥臂电容电压控制基本相互独立,易于实现分布式控制。提出一种电流前馈控制方案,能有效减小电容电压的动态波动,提高动态响应速度。搭建了10kVA三相MMC实验样机,实验结果验证了所提控制方案的可行性和有效性,并具有优良的动静态特性。

英文摘要：

This paper analyzed the active power in modular multilevel converter（MMC）, and presented a comprehensive control scheme for the dc-link voltage and the arm capacitor voltages of MMCs. This scheme employs the arm current direct control, can simultaneously control the ac side currents, dc-link current and inner circulating currents, and does not require a dedicated inner circulating current controller. With this scheme, the capacitor voltage controller of each arm is almost independent of each other and can be implemented by distributed control. A feed-forward current control scheme was presented, which can effectively reduce the capacitor voltage dynamic fluctuations and improve the dynamic response. A 10 k VA experimental prototype of three-phase MMC was developed. The experimental results verify that the proposed control scheme is feasible and effective, and has excellent dynamic and static characteristics.