Improved global fast terminal sliding mode control-based MPPT method for photovoltaic systems

The output power of a photovoltaic (PV) system fluctuates nonlinearly due to changes in solar irradiance and temperature. This research proposes an improved global fast terminal sliding mode control (IGFTSMC) method for the maximum power point tracking (MPPT) of photovoltaic systems. The IGFTSMC method constructs a unique sliding mode surface that overcomes the parameter limitations of traditional global fast terminal sliding mode control methods, allowing for the use of parameter optimization algorithms to achieve optimal performance. This paper employs the particle swarm optimization (PSO) algorithm to obtain the optimal parameters. The stability of a PV system employing the proposed control method is verified using Lyapunov method. Simulations and experiments demonstrate that, when compared to traditional methods, the IGFTSMC method achieves a smaller ripple, lower error, and faster response speed. Thus, it can be seen to exhibit superior static and dynamic performance.