Parameter extraction of photovoltaic single-diode model using integrated current-voltage error criterion

Abstract

An error criterion is essential in the process of parameter extraction of photovoltaic (PV) modules by fitting I-V curves, which exerts a huge influence on the accuracy of the extracted parameters. This paper proposes a new integrated current-voltage error criterion, named EC-I&V(x), which takes into account the intrinsic I-V properties of the PV module. The deviation in both current and voltage is considered by combining the mean squared error of the current and voltage in different data regions. Four optimization methods are used to validate the proposed error criterion, including guaranteed convergence particle swarm optimization, differential evolution, shuffled complex evolution, and an artificial bee colony algorithm. Different methods with the proposed error criterion are applied to synthetic I-V curves with variable error levels and measured I-V data under different operating conditions. Comparing with the traditional current based error criterion, more accurate results are obtained by using the proposed EC-I&V(x) at different error levels for different optimization methods. The proposed EC-I&V(x) not only improves the accuracy of each extracted parameter but also improves the accuracy of the estimated I-V property near maximum power points.