An Explicit Single-exponential Model as an Alternative to Traditional Solar Cell Models With Series Resistance

The series resistance (R<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</inf>) is a significant parameter to assess the performance of the photovoltaic module (PV) in outdoor conditions. One common approach to express R<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</inf> is through the Shockley equation, yet it is often implicit. In this paper, an explicit equation for R<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</inf> based on the Shockley single-diode model is proposed. Its explicit nature is a very useful feature for direct analytic differentiation and integration. The calculated results from the explicit equation with component parameters as inputs show strong agreement with experimental measurements. Critically, unlike traditional methods, the proposed explicit equation not only enables the determination of R<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</inf> as a function of the values of R<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">sh</inf>, instead of taking R<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">sh</inf> as infinite, and also takes into account the potential errors caused by the varying values of n under different conditions, which enhancing its accuracy and better reflecting real-world conditions. Consequently, this model offers a more precise approach for determining the R<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</inf> of components and can serve as a valuable tool in related applications.