Figure 3: Equivalent circuit for representing a 60-cell module. Each individual cell in this circuit is represented by the1-Diode model shown in Fig. 2. The diode symbols in grey on the left represent bypass diodes.
For our study of the effect of I SC mismatches between the individual cells of the module, we make use of an illumination inhomogeneity map published by Ramspeck [6], describing the cetisPV-Moduletest4 system of halm elektronik GmbH. The 270 cm x 160 cm illumination area of this module tester has an inhomogeneity of +/- 0.4%. Fig. 4 shows a center section of 6 x 10 cell positions of the illumination intensity map published by Ramspeck.