Assuming that the PV cells of a panel are connected in parallel across common terminals a and b as in Figure 6.10. In these conditions, there is no direct interaction among current sources or individual diode voltages because they are considered exactly the same. Therefore, this equivalent model may assume a more compact form, as shown in Figure 6.11. Tests of this equivalent model can be seen as a test carried out on a single panel with individual output voltage and current for the same cell:
The method just described can be extended to equivalent models of series-parallel combinations of PV panels or other arrangements of interest.