Effect of local topography on lightning exposure of wind turbines

This paper presents a new method to determine the influence of the terrain topography in the lightning exposure of wind turbines. The method consists in performing numerical calculations of the electric field in a model of a wind plant including the topography of the terrain, with the purpose to determine which wind turbines are more prone to trigger upward leaders. The method has been applied to a specific wind plant in a mountainous region of southern Europe, and the results have been compared with the lightning detection data measured in that location over a period of five years. The comparison presents a good correlation, in particular related to the identification of the turbines with higher exposure to lightning. The correlation also shows that other additional environmental features may have a significant influence on the lightning exposure of the wind turbines, in particular related to the wind direction.