Design and Implementation of Grid Interfacing System for Renewable Energy Sources

This paper presents an advanced control architecture for a standalone, single-phase micro grid system designed to enhance power quality and ensure frequency stability under diverse operating conditions. The proposed system facilitates the seamless integration of a governor-less micro-hydro turbine, driven by a two-winding self-excited induction generator (SEIG), alongside a wind-powered permanent magnet brushless DC (PMBLDC) generator, a solar photovoltaic (PV) array, and a battery energy storage system (BESS). An Adaptive Sliding Mode Control (ASMC) algorithm is implemented to estimate reference source currents, enabling precise regulation of the micro grid’s voltage and frequency while effectively mitigating harmonic distortion. Furthermore, a secondary sliding mode control mechanism is employed to maintain real-time energy balance by estimating the system’s reference real power, ensuring that the BESS compensates for fluctuations in wind, hydro, and solar generation. To address non-linear load disturbances and improve power quality, a fuzzy logic controller is integrated to suppress harmonic currents. The robustness of the proposed control strategy is validated through comprehensive simulation studies in the MATLAB/Simulink environment, demonstrating consistent grid voltage and frequency stability during sudden load transitions and variable intermittent power penetration.