Multi-objective hybrid GA-PSO optimized PI control for grid-connected PV-fed cascaded H-bridge multilevel inverter

The growing integration of PV energy systems into modern power grids necessitates advanced control techniques to maintain stable operation, fast dynamic response, and high-power quality under nonlinear and time-varying conditions. Cascaded H-bridge multilevel inverters (CHB-MLI) are widely adopted for grid-connected PV applications. This study develops a closed-loop control for a PV Integrated on-grid five-level CHB-MLI aimed at enhanced dynamic response and improved power quality. The hybrid GA-PSO technique is used for optimal tuning of PI controllers governing grid current regulation and DC-link voltage balancing through a multi-objective fitness function. The optimization framework simultaneously minimizes THD, DC-link voltage imbalance, steady state error and settling time. The simulation results are obtained by using MATLAB/Simulink, which demonstrates the feasibility of the proposed controller. Real-time validation using an OPAL-RT simulator further confirms the robustness and practical effectiveness of the hybrid GA-PSO-based PI control.