Coordinated control of DC voltage and capacitance balance in a neutral-point-clamped three-phase active power filter based on deep reinforcement learning
XIE Zihang, HUANG Yanguo
School of Electrical Engineering and Automation, Jiangxi University of Science and Technology, Ganzhou, Jiangxi 341000
Abstract：To address the inherent flaws of the traditional control schemes for neutral-point-clamped three-phase active power filters, including the coupling between direct current bus voltage regulation and neutral-point voltage balancing, slow dynamic response of proportional-integral (PI) controllers, parameter tuning that relies on engineering experience, and poor disturbance rejection performance, this paper proposes a coordinated control strategy for direct current side voltage based on the deep deterministic policy gradient algorithm. This strategy constructs a Markov decision process tailored to the high- frequency switching characteristics and dual control objectives of the active power filter, devises a composite reward function, and imposes a gradient-based penalty on voltage errors via the second-order Euclidean norm, so as to achieve unified error-free control of direct current bus voltage stabilization and split capacitor voltage balancing. Simulation verification through Matlab/Simulink demonstrates that under typical operating conditions including capacitor parameter mismatch, direct current voltage startup, and grid voltage sags, compared with the traditional proportional-integral control, the proposed method reduces the direct current bus voltage regulation time by 57.1%, shortens the neutral-point capacitor balancing adjustment time by 55.6%, and lowers the total harmonic distortion of the grid-side current to 2.57%. The proposed method also exhibits stronger robustness under grid disturbances, which provides a novel approach for direct current side multi-objective coordinated control of this type of active power filters.
谢紫航, 黄艳国. 基于深度强化学习的中点钳位型三相有源电力滤波器直流电压与电容平衡协同控制[J]. 电气技术, 2026, 27(9): 1-10.
XIE Zihang, HUANG Yanguo. Coordinated control of DC voltage and capacitance balance in a neutral-point-clamped three-phase active power filter based on deep reinforcement learning. Electrical Engineering, 2026, 27(9): 1-10.
2026, Vol. 27 
