Double Closed-Loop Control of MPPT for the Photovoltaic System Based on Perturbation Observation

This paper fully considers the influence of external light intensity and temperature changes on the output power of the photovoltaic (PV) power generation system. Based on the sliding mode control (SMC) and traditional perturbation observation (P&O) method, an improved double closed-loop control strategy is proposed for the maximum power point tracking (MPPT) of the PV system. Firstly, according to the traditional SMC idea, the SM surface considering the adaptive P&O offset compensation, is designed according to the trajectory of the characteristic output curve of the PV panel. Then, the stable area is derived, and the optimal parameters are designed based on the Lyapunov stability theorem. Finally, different control strategies are analyzed by simulation to verify the correctness and effectiveness of the proposed method.