Power Quality Enhancement in Grid-Connected Solar PV and Battery Energy Storage Systems Using STBC Controller with CSA Algorithm

This paper proposes a robust approach for managing nonlinear power flow in microgrids by integrating a super twisting-based backstepping controller (STBC) with the Circle Search Algorithm (CSA) for maximum power point tracking (MPPT). By means of grid-connected solar photovoltaic (PV) systems with battery energy storage, the proposed solution eliminates the limitations of conventional MPPT algorithms, which suffer under quickly changing atmospheric conditions due to the nonlinear behavior of PV modules. Although the CSA MPPT approach efficiently recovers maximum power from the solar PV system, the STBC controller provides dependable battery charge and discharge operations and eliminates nonlinearities in solar power producing. Comparative analysis using CSA-PI and CSA-STSMC controllers shows the value of the STBC controller in reducing Total Harmonic Distortion (THD) and increasing power quality in the grid and battery system. Resilience of the proposed system, faster tracking speed, and better convergence to low error levels are shown by simulations run in a MATLAB/Simulink environment. The results show that the STBC-based approach considerably improves system stability and power extraction, therefore providing a practical means to improve the power quality in microgrids containing renewable energy sources.