Finite Element Modeling, Analysis, and Life Prediction of Photovoltaic Modules

Abstract

A Photovoltaic (PV) module consists of layers of different materials constrained together through an encapsulant polymer. During its lamination and operation, it experiences mechanical and thermal loads due to seasonal and daily temperature variations, which cause breakage of interconnects owing to fatigue. This is due to the fact that there is a coefficient of thermal expansion (CTE) mismatch because of the presence of unlike materials within the laminate. Therefore, thermomechanical stresses are induced in the module. The lifetime of today's PV module is expected to be 25 yr and this period corresponds to the guarantee of the manufacturer. Its high reliability will help it to reach grid parity. But, the problem is that it is not convenient to wait and assess its durability. In this work, material of each component of PV module is characterized and finiteelement (FE) structural analysis is performed to find the initial condition of the components of the module after manufacture. It was found that the copper interconnects undergo plastic deformation just after the lamination process. A thermal model was numerically developed and sequentially coupled to the structural model. By using the meteorological data of Jeddah, Saudi Arabia, average life of PV module was estimated to be 26.5 yr.