Ricerc@Sapienza

Large-scale ground-mounted PV plants, because of their large extend and localization, can be subject to lightning strikes. When a lightning strike falls into the area of the PV plant, the earthing system is affected by the current flowing in the lightning channel and potentially dangerous overvoltages may occur. Thus, the investigation on the performance of the grounding system is of paramount interest for the prediction of the potential threats either for people working in (or animals passing through) the solar farm area and for the installed electric and electronic equipments.

The paper illustrates a numerical procedure for the computation of mutual transient overvoltages transferred among typical grounding systems of wind turbines belonging to the same wind farm. We use a hybrid approach based on circuit theory and Method of Moments in the frequency domain. The transient response is obtained by means of the Inverse Fourier Transform efficiently computed trough a double-exponential formula.