Solmetric PVA-1000S, Руководство пользователя

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7 Interpreting Measured I-V Curves
7-9
Array Is Partially Shaded, or non-uniform soiling or debris is present
Partial shading of a PV cell reduces the current capacity of that cell, which in turn reduces the maximum current that
can be produced by other series connected cells. For example, slightly shading one cell in a 72 cell module that has 3
bypass diodes will slightly reduce the current in 24 cells. Bypass diodes prevent that cell from going into reverse
bias. If the PV module is supplying a load and the current demanded by the load is above the (reduced) current
provided by the partially shaded cells, the bypass diode will begin conducting and pass current around the shaded
cell strings. Without the bypass diode present, the cells would be reverse biased, which can generate potentially
damaging reverse breakdown voltage and hotspot failure, as discussed in