Guided wave approach for inline photovoltaic module component inspection

Abstract

Reliability of photovoltaic modules is one key factor for being financially attractive for customers all over the world. The further reduction in manufacturing costs lead to increased demands on module components and their materials to maintain acceptable mechanical yields and module reliability. Thus fast, economic and preferably non-destructive component characterization and manufacturing process control methods come more and more into focus. In the present work lamb wave based approaches for material characterization of plate-like photovoltaic module components were evaluated with respect to their precision and inline capabilities. The second-order elastic constants (Young’s modulus and Poisson’s ratio) were determined by automated numeric fitting of the Rayleigh-Lamb dispersion model on experimental data. Furthermore, the influence of mechanical stress on the ultrasound transport properties was investigated. Therefore the components were systematically loaded by mechanical and thermal stress. The resu...