Development of an Optimized PID Control Strategy for PV-Integrated Microgrids in Modern Power System

Abstract

This work presents the design and analysis of an optimized Proportional-Integral-Derivative (PID) controller for photovoltaic (PV)-based microgrids integrated into power systems. Conventional PI controllers often suffer from issues such as prolonged oscillation time, high amplitude responses, excessive overshoot, and persistent steady-state errors—particularly during fault conditions in PV microgrids. To address these limitations, this study aims to introduce and evaluate an optimized PID controller that enhances system responsiveness and improves stability under both DC and AC fault conditions. The proposed controller is designed to maintain current regulation stability during outages caused by unsymmetrical faults, considering scenarios with varying load demands and transmission line lengths. A PI controller is implemented within the current regulation loop, and the gains of the DC/DC boost converter are tuned using a trial-and-error approach to ensure stable current flow during faults. Comprehensive stability and performance evaluations are conducted using Bode plots and pole-zero mapping techniques in MATLAB/Simulink to validate the effectiveness of the control strategy. The performance of the optimized PID controller is compared against a conventional PID controller under multiple scenarios. The results demonstrate improved dynamic response, reliability, and system robustness. Overall, the proposed control design, tuning methodology, and analytical validation under unsymmetrical fault conditions confirm its suitability for enhancing PV-based microgrid operations.