Lightning attachment characteristic of wind turbine generator: Experimental investigation and prediction method based on simulations

Abstract

As the height of wind turbine increases, the lightning strike accident has become a non‐negligible issue. In this paper, the lightning attachment characteristic of a 2‐MW wind turbine generator (WTG) is investigated using a model with a reduced scale of 100. The WTG model is equipped with receptors on the blades and a lightning rod on the nacelle, both serving as its external lightning protection system (LPS). The high‐voltage electrode, which delivers a lightning impulse voltage from a Marx generator, is used to simulate the final stage of downward negative lightning strikes from 29 coming‐leader positions. The experimental results indicate that lightning leaders from either front directions or side directions could be intercepted effectively by LPS, whereas the back‐direction lightning could not. Moreover, with the increase of striking distance, the capture ratio for the insulation part of blade decreases. Electric field intensity distribution simulations for the full‐scale WTG model, using conditions similar to their experimental counterparts, are conducted and compared with the lightning attachment distribution. Based on classical electro‐geometrical model, a simulative method is proposed to predict the lightning attachment distribution of WTG. Our results indicate that it is feasible with this method to produce a satisfactory approximation to the experimentally obtained lightning attachment distribution.