Abstract：With the high penetration of wind power integration into the sending-end of DC transmission

systems，DC sending-end voltage stability issues face new challenges. The DC sending-end voltage stability

problems triggered by commutation failures exhibit a "low-first-then-high" variation trend. While reactive power

imbalance occurs，it is also accompanied by significant fluctuations in DC transmitted active power. If the active

power output of wind turbines during transient periods is not controlled，active power surplus may occur，

exacerbating transient over-voltage and adversely affecting transient voltage stability. Therefore，a transient voltage

stability control strategy based on the soft actor-critic（SAC）algorithm was designd. The strategy taken DC

voltage，DC current，and sending-end converter bus voltage as state variables，and used active and reactive power

command values of wind turbines as action variables，fully considering the coordination between DC system

dynamic characteristics and active/reactive power output at the DC sending-end. Meanwhile，a reward function that

simultaneously addresses both transient low voltage and overvoltage issues was designed to facilitate the SAC

agent in finding optimal control strategies，enabling effective suppression of both transient low voltage and

overvoltage problems. The feasibility of the proposed control strategy was validated through a co-simulation

platform combining Python，Matlab，and PSCAD，providing theoretical foundation and technical support for

practical engineering applications.

        Key words：high penetration of wind power integration；DC sending-end system；commutation failure；soft

actor-critic（SAC）algorithm；transient voltage stability control

     Format Citation:全芷莹，陈冠熹，胡轩林,等. 基于SAC算法的直流送端系统暂态电压稳定策略研究[J].电气传动,2026,56(10):43-51,88. QUAN Zhiying，CHEN Guanxi，HU Xuanlin,et al. Research on transient voltage stability strategy for DC sending-end system based on SAC method [J].Electric Drive, 2026,56(10):43-51,88