a model for the output characteristics of photovoltaic strings is established. By using numerical solutions
a method for calculating the model parameters and maximum power point under any ambient temperature and irradiance is proposed. Furthermore
a time series output characteristics model of photovoltaic strings is developed. For faults such as aging
potential-induced degradation (PID)
micro-cracks
and hotspots
the differential change patterns under different types and degrees of faults are studied. According to the variation characteristics of the time series and global maximum power point curves
fault features are identified and extracted to distinguish fault types and describe fault severity. Simulation and experimental results show that the established model and proposed method can accurately fit the measured data. The calculated model parameters and global maximum power points under various irradiance levels and ambient temperatures exhibit distinct variation patterns. The proposed fault feature metrics can effectively differentiate fault types and describe changes in fault severity.
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