Assessment of explicit models for different photovoltaic technologies

Abstract

Accurate and simple mathematical models are usually required to assess the performances of photovoltaic devices. In particular, it is common practice to use explicit models to evaluate the current–voltage (I–V) performance curves, mainly based on simple analytical expressions that enable the parameters determination with a little computational effort. Six different explicit photovoltaic models (i.e., explicit I–V equations) by different authors (Akbaba & Alattawi; El-Tayyan; Karmalkar & Haneefa; Das/Saetre et al.; Das; and Pindado & Cubas) are analyzed and compared. This comparison is carried out by fitting these models to eight I–V curves for different technologies, including Si, Si polycrystalline, Ga–As, and plastic solar cells. The accuracy of each model depends on the photovoltaic technology to which it is applied. The best fit to each I–V curve studied is normally obtained with a different model, with an average deviation under 2% in terms of short-circuit current (normalized RMSE). In general, the model proposed by Karmalkar & Haneefa shows the highest level of accuracy, and is a good fit for all I–V curves studied.