This paper conducts a test study on the hot spot temperature of modules prepared by current mainstream module products, especially large-size cells, and specifically analyzes the key influencing factors affecting the hot spot temperature. The hot spot temperature of the shaded cells is determined by the power dissipated per unit area Φq, i.e., it is related to the number of cells in a single string, the cell leakage current, and the distribution of the cell leakage current. The non-uniform heating at the cell leakage point is the main reason for the high local temperature of the hot spot. At the same time, this paper discusses the hot spot risk control of modules with a relatively large number of single-string cells. The control of cell leakage current value at reverse bias voltage can effectively reduce the hot spot temperature. The screening of cells based on the temperature difference between cell leakage point and non-leakage area at reverse bias voltage can further control the hot spot risk.
Key words
solar cells /
PV modules /
leakage current control /
hot spot temperature /
shading ratio
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References
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