Parameters extraction method of PV model based on key points of I-V curve

In this paper, a new analytical method is proposed to extract all five-parameter of solar cell, namely the shunt resistance, series resistance, diode ideal factor, photo-current, and reverse saturation current density, based on the one-diode model of silicon solar cells. By applying the relationship between the slope of I-V curve and five parameters, five individual algebraic equations are established, and the limitation of open-circuit voltage and maximum power point on sampling position is eliminated. With this merit, the method proposed in this paper is suitable for a wider application field such as partial shading status. After validated by measured data of different kinds of solar cells under different illumination and ambient temperature conditions, the method has been demonstrated to show good agreement with the measured values. Furthermore, the extracted result of parameters can be used as a basis to diagnose and analyze the working status of PV modules.