Operating Principle of Shadowed C-Si Solar Cell in PV-Modules
Abstract
One of the most crucial issues for PV modules is the thermal stability during shading situations. Principally, the hot spot risk can be attributed directly to the properties of the solar cell. The increased hot spot risk at cells results on the one hand from local shunts, deformations of the p-n-junction, impurities and the resistance of the raw wafer material and on the other hand from bad cell processing. The risk can be reduced by using shorter solar cell strings and by using advanced in-line quality control tools for cell testing. This work presents the investigation about the operating principle of shadowed solar cells in PV modules. Thereby a focus is the understanding of the current flow in the dark and in the irradiated part of the shadowed cell. Finally, by means of this current examination the dissipated power can be determined.