Selecting a suitable model for characterizing photovoltaic devices

The aim of this work is to evaluate a simple analytical method for extracti ng parameters involved in the photovoltaic module behaviour equation. Based on a series of experimental voltage-intensity curves obtained under variou s temperature and irradiance conditions, values are obtained to extract the model parameters, giving rise to adjustment errors at data points (short c ircuit current, open circuit voltage and voltage at maximum power point) an d in the entire curve that are less than 1%. It has also been confirmed tha t assigning suitable values for series and parallel resistance avoids havin g to know beforehand the slope value of the characteristic curve, which is not normally indicated in the solar module specifications; this gives rise to good adjustment results between the experimental curves and the theoreti cal model, even when the theoretical parameters are adapted to other temper ature and irradiance conditions. (C) 2001 Elsevier Science Ltd. All rights reserved.