Degradation Assessment of Photovoltaic Module Based on Probability Distribution Analysis of Model Parameters

In recent years, the intelligent operation and maintenance of the photovoltaic (PV) systems attracts much more attentions. The prognosis and health management of PV array is a critical part of this issue. The conventional degradation prognosis approaches attempt to predict the degradation ratio based on the measured historical power of PV array and the meteorological data. In this paper, the long term measured current-voltage (I-V) characteristic data of the PV module are used to extract the electrical and model parameters for the detail analysis of the degradation of the PV module. The probability distribution of the model parameters under different irradiance levels are investigated. Hopefully, the performance degradation trends of the PV module can be further prognosed by assessing the probability distribution trends of the extracted parameters.