Study of the potential-induced degradation kinetics

摘要

A dedicated set-up which allows a real-time characterization of the PV modules, while being subjected to the Potential-Induced Degradation (PID) test, was developed and tested. This real-time characterization includes the measurement of the dark I/V curve and the acquisition of electroluminescence (EL) images at different biasing levels. By means of this real-time characterization it is possible to early identify the PID presence and its kinetics during the total duration of the test. This set-up allowed the investigation of the influence of salt as an impurity in module packaging with regard to PID. To this aim, a mini-module contaminated with salt including on the surface of one of its solar cells and in the glass-EVA interface was laminated. This mini-module showed an increased susceptibility to PID, which developed also in the uncontaminated solar cells. Repetitions of the PID test showed that its influence diminished with the number of cycles.