Experimental comparative study of photovoltaic models for uniform and partially shading conditions

Abstract

Understanding and correctly modeling photovoltaic (PV) systems under conditions of partial shading become necessary and important for the development of PV technologies. For this, conventional PV models do not work correctly. Thus, it is necessary to adapt the conventional models to respond to partial shading situations, which is still a challenge. In this paper, as a novelty PV model originally applied for uniform conditions are integrated with the superposition technique for partially shading conditions considering the voltage drop in the diodes. In addition, the bypass diode behavior under operation stands out. For this, we experimentally tested three PV models: one-diode model with series resistance; one-diode model with series and shunt resistances; two-diodes model with series and shunt resistances. In seven different scenarios of shading, their performance is evaluated. As a result, the one-diode model with series and shunt resistances presented the best performance under uniform and partially shading conditions. Relating a mean error of 1.68% in I-V curves and 0.99% in P-V curves. Thus, we implement the curve superposition technique with the consideration of the voltage drop in the diodes. And finally, the paper validated experimentally the application of the superposition technique in PV models for partially shading conditions.