Maximum power point tracking of photovoltaic generation based on the fuzzy control method

Abstract

The power available at the output of photovoltaic cells keeps changing with solar insolation and ambient temperature because photovoltaic cells exhibit a nonlinear current-voltage characteristic. So photovoltaic cells' maximum power point varies with solar insolation and ambient temperature. With the improved efficiencies of power electronics converters, it is now possible to operate photovoltaic power systems at its maximum power point (MPP) in order to improve the overall system efficiency. This paper presents a fuzzy control method for tracking maximum power point in photovoltaic power systems and the control system is established simultaneously. In this paper, simulation model of photovoltaic system's maximum power point tracking based on the fuzzy control method is developed in the MATLAB software. The results of simulation show that the fuzzy control algorithm significantly improves the efficiency during the tracking phase as compared to a conventional algorithm about maximum power point tracking (MPPT) in photovoltaic power systems. It is especially suitable for fast changing environmental conditions. Furthermore, the proposed algorithm is simple and can be easily implemented with any fast micro processor such as a digital signal processor.