A Combined Newton-Raphson and analytical technique for parameter estimation of solar photovoltaic modules

Abstract

The performance of a solar photovoltaic (PV) module under varying environmental conditions can be determined if the current-voltage characteristic curve of the solar PV cell is obtained. In this study, a combination of Analytical and Numerical methods was used to estimate the unknown electrical parameters of a one-diode solar PV cell model such as photon current, diode dark saturation current, shunt resistance, series resistance, and the diode ideality factor was considered. In this study the Newton Raphson method was used to extract one of the unknown electrical parameters, and analytically other unknown electrical parameters were solved. To validate the high performance and accuracy of the proposed method, two PV modules (poly-crystalline, mono-crystalline) were tested. It is revealed that the solar PV module characteristics obtained with the proposed method were closer to characteristics obtained by the manufacturer datasheet than with the Newton Raphson alone. Also, a very negligible relative maximum power error was observed with the proposed method than the existing Newton Raphson method.