Design and Real-Time Validation of Higher Order Sliding Mode Observer-Based Integral Sliding Mode MPPT Control for a DC Microgrid

In a photovoltaic (PV) system-based microgrid, maximum power point tracking (MPPT) control plays a crucial role to improve the efficiency and stability. Since the past few years, one of the key control schemes to enhance the effectiveness of the microgrid is the observer-based MPPT control. This article proposes a higher order sliding mode observer (HOSMO)-based integral sliding mode control (ISMC) for MPPT control to ensure an efficient operation of a closed-loop dc microgrid. The proposed MPPT control is mainly focused on obtaining a chatter-free output voltage and stabilized output power from the PV-system-based microgrid and further ensure insensitivity to uncertainties and reduction in steady-state error. ISMC is applied to carry out finite-time stabilization throughout the entire response of the system. To justify the efficacy of the proposed approach, various test scenarios are simulated in real-time, and the performance is investigated through extensive comparative results. The MATLAB simulations and real-time simulation results achieved with OPAL-RT are compared. The superior performance of the proposed approach is observed in terms of high efficiency, good accuracy, and robust performance under varying meteorological conditions.