A procedure to calculate the I-V characteristics of thin-film photovoltaic modules using an explicit rational form

摘要

Accurate models of the electrical behaviour of photovoltaic modules are effective tools for system design. One or two diode equivalent circuits have been widely used even though some mathematical difficulties were found dealing with implicit equations. In this paper, a new model based on a simple rational function, which does not contain any implicit exponential form, is presented. The model was conceived in order to be used with thin-film photovoltaic modules, whose current-voltage curves are characterised by very smooth shapes. The parameters of the model are evaluated by means of the derivatives of the issued characteristics in the short circuit and open circuit points at standard rating conditions, and assuming that the calculated current-voltage curve contains the rated maximum power point of the simulated panel.