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该文针对应用于高压直流互联系统的高频链模块多电平直流变压器(high-frequency-link modular multilevel DC/DC transformer,H-M2DCT)移相控制策略进行研究.首先,提出移相控制在该结构直流变压器中的应用原则,并对该方法下的H-M2DCT运行特性进行详细分析,同时提出其适用于不同调制方法的通用数学模型;在此基础上提出H-M2DCT基于移相控制原理的分布式控制系统架构.在该架构下,H-M2DCT分别以两个全桥组别的独立相桥臂为基本控制单元进行分布式控制,每个桥臂之间的控制系统相互独立,且具有模块化与即插即用等特点,并利用该架构设计H-M2DCT的3种工作模式,从而拓宽其应用场景;同时,根据H-M2DCT的高频特性,提出适用于H-M2DCT的轮换电容电压平衡策略,减小了调制系统的计算负担与换流器的开关附加损耗,从而提高了每个桥臂调制系统的运行速率与换流器的运行.最后,基于新一代SiC功率器件,通过样机实验,对所提出的基于通用数学模型的控制管理策略及轮换电容电压平衡策略进行验证,实验结果证明了所建通用数学模型的正确性及所提策略和方法的有效性.“,”This paper presented a phase-shift control method for high-frequency-link (HFL) modular multilevel DC transformer (H-M2DCT) which is designed for high-voltage DC interconnection system. Firstly, the phase-shift control principles for H-M2DCT were proposed, and the operating characteristics were analyzed in detail. Besides, the general mathematical model suitable for different modulation methods was derived. Based on this model, distributed control system architecture of H-M2DCT under the phase-shifted control was presented. In this architecture, H-M2DCT was divided into two independent phase branches of the independent phase in arm as the basic control unit for distributed control. Each control system in arm is independent, and it has modular and plug and play characteristics. Three H-M2DCT working modes were designed by using this architecture, thus the application scenes of H-M2DCT could be broaden. Meanwhile, to reduce the computational burden of the modulation system and improve the running rate of each arm modulation system, this paper proposed an alternate modulation balance algorithm (AMBA) based on the high frequency characteristic of H-M2DCT. Finally, a prototype based on SiC power devices was accomplished and the proposed control management strategy and AMBA is verified by experimental results.