Page 91 - Applied Photovoltaics

I same current! cell 2 has lower output caused by:
1 x manufacturing defects
x degradation (e.g. cracking)
x partial shading (e.g. trees,
buildings, leaves, bird
droppings, discoloured
encapsulant etc.)
2

Figure 5.5. Mismatched cells connected in series.

Figure 5.6. Series-connected mismatched cells and the effect on voltage. The
combined curve is determined by summing the voltages V 1 and V 2 for each
current I.

Figure 5.7. An easy method of calculating the combined I sc of series-connected
mismatched cells. The current at the point of intersection represents the short
circuit current of the series combination (i.e. V 1 + V 2 = 0).

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