Design of a Three-Phase PWM Rectifier Based on Improved Whale Optimization Algorithm Optimized Fuzzy Control

Abstract

To address the issues of slow dynamic response and insufficient anti-interference capability in the traditional voltage outer-loop PI control of three-phase PWM rectifiers, this paper proposes a control strategy based on an improved Whale Optimization Algorithm (WOA) optimized variable domain fuzzy PID. First, a voltage outer-loop control model is established in the two-phase rotating dq coordinate system. Second, to improve the slow dynamic response of the traditional PI voltage outer loop, fuzzy control combined with PI control is introduced, incorporating correction factors for the proportional and integral coefficients. Then, to better adapt the fuzzy PI control to the nonlinear characteristics of voltage and current, the Whale Optimization Algorithm is used to optimize the scaling factors of the variable domain fuzzy control, thereby solving the problem that traditional control cannot adjust parameters in real time. Finally, a system model is built in Matlab/Simulink for simulation experiments under step changes in DC voltage reference and load. The results show that after applying the improved WOA-optimized fuzzy PI control, the total harmonic distortion of the current is significantly reduced, the DC voltage recovery time is shortened with less overshoot, and the system dynamic response speed and disturbance robustness are improved.