Review: Ultraviolet Fluorescence as Assessment Tool for Photovoltaic Modules

作者：Marc Köntges, Arnaud Morlier, Gabriele Christine Eder, Eckhard Fleis, Bernhard Kubicek, Jay Lin · 发表于：IEEE Journal of Photovoltaics · 年份：2020 · DOI：10.1109/jphotov.2019.2961781 · 被引用次数：90 · 研究领域：Photovoltaic System Optimization Techniques、Photovoltaic Systems and Sustainability、Silicon and Solar Cell Technologies

Since 2010, the ultraviolet fluorescence (UVF) method is used to identify defects in wafer-based crystalline silicon photovoltaic (PV) modules. We summarize all known applications of fluorescence imaging methods on PV modules to identify defects and characteristics. The aim of this review is to present the basic principles for the interpretation of UVF images. The method allows for detection of cell cracks in a chronological order of occurrence, visualizing hot parts in a PV module, and identifying deviating bill of materials of PV modules. The effects of various material combinations on the UVF are reproduced in the lab and explained for the first time. Seasonal effects on the UVF are presented for the first time. In addition, some not yet understood features in the images are shown and discussed. Furthermore, the application of UVF imaging for manual, hood-based, and drone-based inspection is presented. The analysis speed of the three methods has been measured under real conditions. For the manual inspection, we found an evaluation speed of 250 modules/h, for a hood-based system 200 modules/h and the drone-based method allows an imaging speed of up to 720 modules/h.