Numerical Simulation on the Distribution of Ion Flow near Wind Turbine Under Thundercloud

Abstract

Lightning damage is a huge threat to wind turbine, which influences the safe operation of wind turbine. There are some applications of lightning protection system (LPS) on wind turbine, especially on wind turbine blades. However, the rotation of wind turbine will influence the distribution of charged ions near blade tip, increasing the difficulty of full lightning protection on wind turbine. In this paper, 2-D drift and convection model coupled with Poisson equation of charged particles near wind turbine blade under thundercloud was established, based on which the distribution of glow corona ions near blade tip was calculated. The influence of blade rotation and polarity effect were further studied. As a result of the rotation, the high density of charged ions accumulates like arc shape at the side in the negative rotating direction. And the positive ions have an effect on the electric potential making it invert to positive mainly at the same direction. Under positive thundercloud, positively charged particles distort the field and have a shielding effect on the electric field, so that the upward leaders under negative thundercloud are easier to initiate.