Fuzzy modeling of photovoltaic panel equivalent circuit

For simulation purposes of photovoltaic (PV) system using MATLAB and for on-line application the different parameters of the PV panel have to be known at the specific operating point. The parameters of interest are the photon current, the series and shunt resistance's, the ideality factor, and the diode reverse saturation current. Hence the different parameters have to be known at all operating conditions which is practically not available in many cases. So, in this paper we introduce a new type of data analysis that expresses these parameters by means of a fuzzy regression model. The available PV array under consideration is defined by the manufacturer's data sheet which specifies the panel under a narrow range of operating conditions. A fuzzy model has been developed for the aforementioned PV arrays. The model has been validated using a set of data that have been obtained at our site or obtained from extrapolating data from the manufacturer's data sheet.