Complete parasitic capacitance model of photovoltaic panel considering the rain water

Common mode current suppression is important to grid-connected photovoltaic (PV) systems and depends strongly on the value of the parasitic capacitance between the PV panel and the ground. Some parasitic capacitance models have been proposed to evaluate the magnitude of the effective parasitic capacitance. However, the proposed model is only for the PV panels under dry and clean environmental conditions. The dependence of rain water on the capacitance is simply described rather than analyzing in detail. Furthermore, the effects of water are addressed quite differently in papers. Thus, this paper gives complete parasitic capacitance model of the PV panel considering the rain water. The effect of the water on the capacitance is systematically investigated through 3D finite element (FE) electromagnetic (EM) simulations and experiments. Accordingly, it is clarified how the water affects the parasitic capacitance and methods of minimization of the capacitance are proposed.