Enhancing Efficiency in Grid-Connected Photovoltaic Systems Using Robust Third-Order Super-Twisting Sliding Mode Control

Abstract

Abstract This article presents a new strategy to enhance the maximum power point tracking (MPPT) method for optimal power extraction from photovoltaic (PV) panels, as well as an inverter control strategy for regulating the active and reactive power injected into the grid in a double-stage singlephase photovoltaic installation. The proposed method is based on a robust Third-Order Super-Twisting Sliding Mode Control (TOSTC).In the first stage, TOSTC is used to control the boost converter in order to ensure fast and accurate tracking of the maximum power point, even under varying environmental conditions, while reducing chattering and minimizing power losses. In the second stage, TOSTC is applied to control the inverter current, enabling precise regulation of both active and reactive power injection, and significantly reducing harmonic distortion, accordingly, improving the overall power quality delivered to the grid. The article compares the performance of the TOSTC with conventional control methods, namely the PI controller for the boost converter and the PR controller for the inverter, all implemented in the MATLAB/Simulink environment. Simulation results demonstrate the superiority of the TOSTC approach in terms of tracking speed, accuracy, and harmonic reduction. The stability of the proposed controller is validated using Lyapunov criteria, and its effectiveness is confirmed through simulations under both dynamic and steady-state conditions, highlighting the robustness and reliability of this innovative control strategy for grid-connected photovoltaic systems