PV module life prediction based on coupled failure model

Abstract

Due to environmental stresses, photovoltaic (PV) modules operating outdoors may trigger multiple power degradation patterns. In this paper, four types degradation patterns are studied, among which humidity cycling is proposed for the first time. To verify the necessity of the proposed humidity cycle degradation, the sensitivity of the environment on the output power of PV modules is analyzed using orthogonal tests, and the results show that the power degradation of PV modules by humidity cycle is second only to the damp heat degradation. In addition, a method to model the coupling relationship between each degradation patterns based on weight values is proposed to accurately quantify the influence of environment on the output power of PV modules, and the accuracy of the model is verified by actual power plant data.