Design and implementation of microcontroller based fuzzy logic control for maximum power point tracking of a photovoltaic system

This paper proposes a microcontroller based control method for the maximum power point tracking (MPPT) of a photovoltaic system under variable temperature and insolation conditions. For the reduction of tracking time, fuzzy logic control algorithm is implemented with the embedded microcontroller for improved performance as compared to conventional techniques in power efficiency and swift maximum power point tracking. The system includes a photovoltaic array, a PWM controlled DC-DC converter and sensor circuits. The designed controller regulates the converter output voltage by varying duty cycle of the PWM signal using maximum power point (MPP) algorithm and it maximizes the output power extracted from photovoltaic array. This paper discusses the low cost implementation of MPP algorithm in a 8-bit microcontroller using the tools and techniques to generate optimized real time code in C for ATMega8 microcontroller which will demonstrate how maximum power point tracker might provide elegant and efficient solution for increasing the efficiency of a solar system based on experimental results rather than on mathematical models.