Simplified Lambert W-Function Math Equations When Applied to Photovoltaic Systems Modeling

Abstract

In this article, simplified and easy-to-work-with equations for the Lambert W-function are derived. This function is widely used to solve equations related to photovoltaic systems. More specifically, this mathematical function represents a useful tool when modeling solar cells/panels performance (that is, the current-voltage curve) by analytical approaches. However, the Lambert W-function has a complex solving process which might represent an unaffordable mathematical challenge for a great number of professionals/technicians in the photovoltaic industrial sector. Simple approximations for the Lambert W-function on both of its branches (positive and negative) are proposed in this article. The results of the present article show a simple but accurate way for photovoltaic systems modeling, even when these systems comprise a maximum power point tracking subsystem.