An Improved Numerical Approach for Photovoltaic Module Parameters Acquisition Based on Single-Diode Model

Abstract

This paper presents an easy and an improved numerical approach of modeling photovoltaic (PV) modules. An accurate current-voltage (I-V) model of PV modules is inherently implicit and non-linear and calls for iterative computations to obtain an analytical expression of current as a function of voltage. In this paper, a numerical approach is proposed to forecast the PV module performance for engineering applications. The proposed approach was implemented in a Matlab script and the results have been compared with the datasheet values provided by manufacturers and other approaches in standard test conditions (STC). This approach permits to extract five unknown parameters and also allows quantifying the effects of panel temperature and irradiance on key cells parameters. The model is validated by covering a wade of operation conditions using only information provided by the manufacturer’s datasheet. The various equations of the model are presented in details in this paper. Unlike other cell modeling techniques, this proposed approach enables computation of model parameters at any environmental conditions. The advantage of this model is its ability to compute simultaneously all the model parameters. A modification is also reported in the Newton-Raphson’s solving to attain the best convergence.