Improving Particle Swarm Optimization-Based Fuzzy PI Control for Photovoltaic Grid-Connected Inverters

To address the issue of poor dynamic performance in the fuzzy Proportional-Integral (PI) control of photovoltaic (PV) three-phase grid-tie inverters, an improved particle swarm optimization (PSO) based fuzzy PI control strategy is proposed. A mathematical model of the three-phase grid-tie inverter is established, and a dual closed-loop control system for the grid-tie inverter is designed based on this model. Fuzzy control is introduced into the outer voltage loop to adjust the PI parameters in real-time. The improved particle swarm algorithm is employed to optimize the quantization and scaling factors in the fuzzy PI control, enhancing the system's control performance. Simulations conducted on the MATLAB/Simulink platform, compared with fuzzy PI control, demonstrate that this method improves the dynamic process of grid-tie control in PV systems, ultimately achieving smooth grid-tie for the PV system.