Interval type-2 fuzzy maximum power point tracking for solar photovoltaic power charging systems

This paper presents an interval type-2 fuzzy maximum power point tracking (IT2FMPPT) control method for a solar photovoltaic (PV) power generation systems with a DC/DC buck converters and a battery charging system. After the brief model descriptions of the solar PV power charging system, the maximum power and its optimal voltage of the system at different illuminations are numerically solved using a Newton-Raphson method. Via the DC/DC buck converter and the current feedback control technique, the proposed MPPT controller is synthesized using PI control and IT2 fuzzy control logics. The asymptotical stability of the overall closed-loop system with the proposed IT2FMPPT controller is investigated in some details. The effectiveness and merit of the proposed IT2FMPPT controller are exemplified by conducting simulations via Matlab/Simulink. Through comparative simulations, the proposed IT2FMPPT controller is shown superior in comparison with a conventional PI MPPT controller and a conventional fuzzy MPPT controller.