Comparative Analysis of Different Iterative Methods for Solving Current–Voltage Characteristics of Double and Triple Diode Models of Solar Cells

Abstract

The current–voltage characteristics of the double diode and triple diode models of solar cells are highly nonlinear functions, for which there is no analytical solution. Hence, an iterative approach for calculating the current as a function of voltage is required to estimate the parameters of these models, regardless of the approach (metaheuristic, hybrid, etc.) used. In this regard, this paper investigates the performance of four standard iterative methods (Newton, modified Newton, Secant, and Regula Falsi) and one advanced iterative method based on the Lambert W function. The comparison was performed in terms of the required number of iterations for calculating the current as a function of voltage with reasonable accuracy. Impact of the initial conditions on these methods’ performance and the time consumed was also investigated. Tests were performed for different parameters of the well-known RTC France solar cell and Photowatt-PWP module used in many research works for the triple and double diode models. The advanced iterative method based on the Lambert W function is almost independent of the initial conditions and more efficient and precise than the other iterative methods investigated in this work.

Keywords

• equivalent circuits
• iterative methods
• Lambert W function
• optimization
• mathematical models
• solar cells