一种在可变日照条件下对运行中光伏组件进行高质量Suns-EL成像的方法

Abstract Effective and periodic inspection of photovoltaic (PV) modules is essential to guarantee their safe operation at maximum capacity. Although luminescence-based imaging techniques can identify most PV module defects, existing methods require additional electrical contact or can only work under certain sunlight conditions. In this paper, we propose a contactless sunlight-excited electroluminescence (Suns-EL) imaging method to acquire high-quality luminescence images under variable sunlight conditions. We present a partial shading system to separate the cell into an illuminated excitation area and a shaded imaging area for non-disruptive imaging on operating modules. Moreover, we propose two sunlight-insensitive strategies to acquire images with high image uniformity and clear defect structures/textures including: 1) a two-stage framework to remove background noise and obtain high-quality Suns-EL images and 2) a filter selection approach to preserve signal better while suppressing noise based on the analysis of spectral components and energy distributions. Experimental results demonstrate the effectiveness of our proposed method in acquiring high-quality luminescence images of multiple invisible defects in operating PV modules under various sunlight conditions, both qualitatively and quantitatively.