Accurate Three-Diode model estimation of Photovoltaic modules using a novel circle search algorithm

Three-diode model (TDM) of photovoltaic (PV) cells is more accurate model that includes most of the optical and electrical losses of PV module. However, the nonlinearity and parameters of this TDM are higher, which make it complex and challengeable model. This article utilizes an efficient algorithm called the Circle Search Algorithm (CSA) for accurate electrical modeling of PV modules. The CSA is inspired by the circle's well-known geometrical properties and the perpendicular relationship between its radius and tangent line. The CSA and other four algorithms are applied to determine the nine parameters of the TDM of three commercial PV modules. The objective function is the root mean square error (RMSE) between the estimated and measured output currents. The statistical optimization results and convergence curves proved the robustness and speed of CSA in determining the optimum TDM among the other methods. The predicted I-V curves are plotted against observed I-V curves at various temperatures and solar irradiance to demonstrate the CSA's superiority under various scenarios. The absolute current error of the CSA-TDM at maximum voltage is less than that of other algorithms.