A new advanced third-order sliding mode control with adaptive gain adjustment using fuzzy logic technique for standalone photovoltaic systems

The nonlinear behavior of photovoltaic (PV) panels, coupled with their strong dependence on atmospheric conditions, necessitates efficient maximum power point tracking (MPPT) techniques to maximize power extraction, reduce costs, and enhance overall system efficiency. The output power of a PV panel is significantly influenced by current-voltage (I-V) and power-voltage (P-V) characteristics, as well as variations in solar irradiance and temperature. Consequently, advanced MPPT control strategies are required to ensure fast transient response, robustness against disturbances, and minimal steady-state oscillations. This paper proposed a novel MPPT strategy based on a fuzzy third-order sliding mode controller (FTOSMC) designed for PV systems. The proposed approach integrated fuzzy logic control (FLC) with third-order sliding mode control (TOSMC) to adaptively adjust control gains in real time, thereby minimizing chattering, improving tracking speed, and disturbances rejection. The effectiveness of the proposed FTOSMC was evaluated through extensive MATLAB/Simulink simulations, comparing its performance against SMC and TOSMC. Simulation results demonstrated that the proposed FTOSMC-based MPPT method outperformed conventional techniques in terms of faster convergence to the maximum power point (MPP), reduced chattering effects, and improved robustness against environmental fluctuations. These advantages made it a promising solution for PV applications, where system stability and energy efficiency were critical concerns.