Accelerated stress testing of potential induced degradation susceptibility of PV modules under different climatic conditions

Abstract

Potential Induced Degradation (PID) is one of the severe failure modes observed in the field with high system voltage, high humidity and high operating temperature. PV module needs to be tested for PID susceptibility as per site conditions before installation in the field. In this paper the effect of temperature, humidity, and voltage on leakage current, as well as PID, has been analyzed for multi-crystalline silicon and HIT module technologies. Also, reported the effect of PID stress on PV modules in terms of electrical degradation and visual defects. For the studied multi-crystalline module, deviation of degradation between one cycle and three cycles of PID stress for the Isc is 98%, Voc is 18% and Pmax degradation is 87%. This paper also reported a case study about the designing of accelerated stress testing of the PID of the PV module for different climatic zones of India. The stress testing condition was designed at harsh conditions of temperature and humidity for representative sites of climatic zones. It was found that the required testing time for PV module in the case of Hot & humid climatic zone is more as compared to other climatic zones.