Enhancing the Accuracy of an Explicit Solar Cell I-V Model via Low-Complexity Search-Based Parameter Extraction.

A new approach for extracting parameters of the recently introduced explicit two-piece quadratic model (ETPQM) for solar cell current-voltage (I-V) characteristics is proposed. It consists in introducing a new I-V point condition which enables expressing all ETPQM parameters as functions of an auxiliary parameter belonging to a subset of the unit interval, whose optimal value is then found by means of a low-complexity search procedure. The proposed approach is validated for different solar cells via performance (i.e., accuracy and execution time) comparisons against analytical ETPQM parameter extraction and similar low-complexity search-based methods applicable to the one-diode model (ODM). Obtained results show that the proposed method consistently outperforms the original analytical ETPQM parameter extraction in terms of accuracy. Furthermore, when compared to the low-complexity ODM-based methods, it: (i) approaches and, in some cases, surpasses their accuracies; (ii) yields much smaller execution time; and (iii) avoids the problem of wrong maximum power point fitting that may occur when using the considered low-complexity ODM-based methods.