A new model of photovoltaic (PV) panel is proposed. The model precisely replicates sub-cell level degradation, such as cracks and interconnect failures, and reproduces their effect at the panel level I–V characteristic. Moreover, a regression method is proposed, which infers the model's parameters from combination of electroluminescent (EL) image and degraded I–V characteristic. The combination of quantitative (EL image) and qualitative (I–V characteristic) enables to characterize the degradation of the cells embedded in the PV panel, without physical access to the cells. The proposed model and the regression problem is experimentally verified on a set of 3 single cell measurements and a set of 4 crystalline PV panels with various levels of degradation.
Bibliographical noteFunding Information:
The work presented in this publication was possible due to generous cooperation of companies Kmetrics and SolarTester, who shared test-bed measurements for testing the proposed method. The work was supported by a grant from the Innovation Fund Denmark through the project APETT with no.: 6154-00010B and Innovation and Technology Fund, Hong Kong through the project #ITS/308/15.
© 2021 International Solar Energy Society
- Degradation modeling
- Evolutionary algorithm
- Preventive diagnostics