MPPT definition and validation: A new model-based approach

Solar radiation is one of the most accessible renewable energy resources but its employment is strongly influenced by environmental and technological factors. In particular, the conversion process is strictly connected to the irradiance level and to the temperature of the photovoltaic module. Moreover it is well known that the conversion efficiency is quite low, about 15% for common installations. It is extremely important to know the behaviour of the module in order to estimate the efficiency of the solar plant in any condition and to predict the working point where maximum power is converted. This task is performed by the tracker of the Maximum Power Point (MPPT): it maximizes the power output of a PV system for assigned conditions of radiation and temperature, thus optimizing the efficiency. The core of the MPPT is represented by the implemented algorithm devoted to find and maintain the operation near to the Maximum Power Point (MPP). In the present paper, starting from the set of equations modelling a PV module, an innovative procedure to identify and reach the MPP is presented and experimentally verified.