Providing Improved Structure and Adaptive Control Strategy for Solar System with the Ability to Improve Power Quality in Islanded Microgrid

Due to the ever-increasing price of fossil fuels and growing concerns about environmental pollution, the utilization of renewable resources, such as photovoltaic (PV) systems, has witnessed significant growth. However, the lack of an optimal structure and control strategy for PV systems poses a crucial challenge in fully exploiting their potential capabilities. This article proposes a suitable structure and adaptive control strategy for PV systems, enabling the maximum utilization of PV system capabilities in island microgrids. The proposed control structure and strategy are based on a two-stage converter, facilitating maximum power point tracking in PV, injecting the generated PV power into the microgrid with minimal harmonic levels, and improving the power quality of the microgrid by compensating for harmonic components. In this method, the tasks of the DC/AC converter, including the injection of PV active power into the microgrid, provision of reactive power, and harmonic compensation, are prioritized and managed by considering the current peak limitation to prevent inverter overcurrent. Additionally, an adaptive controller is designed to enhance the accuracy and speed of power control. The proposed structure and strategy have been evaluated by simulating a sample microgrid in MATLAB/Simulink. The simulation results demonstrate that the proposed method enables the PV system to operate at maximum power with minimum harmonic levels, leading to a significant improvement in the speed and accuracy of the control system and enhancing the power quality of the islanded microgrid.