A comparison of different one-diode models for the representation of I-V characteristic of a PV cell

Predictive performance tools are an important factor in the success of any new technology because they permit demonstration of whether a system will be efficient and economically feasible. A reliable predictive tool should allow the designer to optimise system performance and to maximise the cost effectiveness of a system prior to installation. This article discusses the five main parametric models for photovoltaic (PV) systems available in the literature. The current-voltage characteristics of a photovoltaic module can be reproduced modelling the PV panel as an equivalent electrical circuit made of linear and non-linear components. The parameters describing such components are directly related to the performance characteristics of the specific PV panel, which are generally available in a graphic form with respect to standard values of temperature and incident irradiance. Five of the most recent models are analysed in detail describing the algorithm, showing how the parameters were determined and highlighting the most important mathematical and physical assumptions that characterised each model and the calculation process. To simplify the examination and reading of the procedures referred to in the five models, all equations are rewritten using the same nomenclature. Furthermore, to assess the accuracy of each model with respect to the data provided by the manufacturer, this paper compares the I-V and P-V curves at various temperatures and irradiance for a generic PV panel.