Photovoltaic module model determination by using the Tellegen’s theorem

Abstract

This paper proposes a generalized methodology to calculate the parameters of the single-diode or double-diode models of a photovoltaic module. The presented method relies in the solution by a simple iterative process of the set of equations obtained from the photovoltaic-module’s equivalent circuit. The use of the generalized form of Tellegen’s theorem allows the solving of the equivalent circuit’s equations in an exact way, without making considerations or approximations commonly used in previous works. The parameters of the equivalent circuit are obtained from the standard conditions of: open-circuit, short-circuit and maximum power, provided by the manufacturer in the data sheet of the photovoltaic module. The presented method is applied to obtain the models of several commercial modules. The accuracy of the obtained parameters is greater than that of the results previously determined by other authors. The curves calculated with the obtained models matches the experimental curves supplied in the manufacturer’s data.