EMTP models of a wind turbine grounding system

Installations of wind turbine generator systems are noteworthy examples of eco-friendly energy generation. Because larger-scale facilities and increased electrical capacity can be realized by increasing the number of turbines, wind energy can be utilized more efficiently than other clean energy sources. However, the number of lightning strikes has increased with the popularization of wind turbine generator systems. The grounding potential, which may cause malfunctions of equipment inside and in the vicinity of the wind turbine and accidents, increases owing to the flow of lightning current into the ground. The grounding potential rise depends on the transient characteristics of the grounding systems. Therefore, it is important to clarify these grounding characteristics. In this paper, an EMTP (Electro Magnetic Transients Program) models using lumped parameters are proposed for a wind turbine grounding system. The EMTP models are verified by comparing with the FDTD models. Incidentally, the FDTD (Finite Difference Time Domain) simulation results have already verified by comparing with measurements on an actual wind turbine site.