Sine Cosine Algorithm-Based Proportional-Integral Controller for Low Voltage Ride Through Enhancement in Grid-Connected Photovoltaic Systems

This paper’s key contribution is an SCA-optimized PI controller (SCA-PI) for reactive power control to enhance low-voltage ride-through (LVRT) in a 5 MW grid-connected PV system (MATLAB/Simulink), tuned via the ITAE objective function. It benchmarks SCA-PI against conventional PI and GWO-PI controllers across 10%, 20%, and 30% voltage sag scenarios plus varying irradiance/load conditions. For the most severe 30% sag, SCA-PI reduced voltage drop from 30.54% to 14.48% and overshoot from 26.07% to 14.35%, demonstrating that a low-cost, internal-controller-based metaheuristic tuning approach can outperform both fixed-gain and GWO-based alternatives without added hardware.