Experimental Analysis of the Electrical Performance of Non-identical PV Solar Modules in Coupling

Abstract

Photovoltaic (PV) generators often require module interconnection to achieve target voltage and current, but non-identical modules can introduce electrical mismatch. The use of photovoltaic (PV) installations is becoming increasingly widespread in electricity generation. The performance of these PV installations is closely linked to that of the PV modules, which present electrical performance issues. Connecting them in series or in parallel helps to improve their electrical performance (voltage and current). This study experimentally compares the electrical performance of asymmetric series and parallel couplings of non-identical monocrystalline silicon PV modules under outdoor, unshaded conditions.  The objective of this work is to conduct a comparative study of the electrical performance of different combinations of PV modules. The internal electrical parameters (Rs, Rsh, FF, η) of series and parallel combinations of non-identical PV modules are examined. Experimental measurements of the current delivered by these combinations of PV modules to an external load and the voltage across these modules are carried out. The results show that the conversion efficiency and form factor of the series combination are 10% and 0.659, compared to 5% and 0.463 for the parallel combination. The shunt resistance values are 433.666 and 29.812 Ω for the series and parallel combinations, respectively. Under the experimental conditions tested, the asymmetric series assembly showed better overall electrical performance than the asymmetric parallel assembly, despite having higher series resistance. These results suggest that mismatch does not systematically degrade all performance parameters in series configurations.