A simple photovoltaic simulator for testing of power electronics

The paper concerns simulation of photovoltaic systems. First, the characteristics of a real photovoltaic module, based on real life measurements, are presented. The peculiar behavior that is due to partial shading and bypass diodes is pointed out. Then a PSpice computer model is outlined, and the computer simulations serve to understand the observed behavior. On this background, the paper presents a simple hardware-based photovoltaic simulator that is able to qualitatively behave like a real photovoltaic module. Novel developments on the signal side are introduced: a modification of the signal side load compared to previous systems is presented, but more importantly, a signal side circuit that can be controlled from a computer to emulate all kinds of irradiance conditions, including partial shading, is also devised and proven to work. Experiments show that the proof-of-concept prototypes function as expected, although there is certainly room for improvements in further work. Such simulators could, and probably should, be used for testing of power electronics based interfaces to photovoltaic systems, as they can provide repeatable laboratory conditions.