基于冲击电位分布的风机新型接地装置优化研究

Optimization of a New Grounding Device for Wind Turbine Based on Impulse Potential Distribution

风电场遭受雷击时,传统接地装置因接地电阻值过大,且雷电流在土壤垂直方向穿透性弱,会导致冲击电位分布不均,局部电位升高等问题。提出了一种新型的立体均压结构,用以扩大雷电流垂直泄流能力,改善地电位的下降梯度。理论计算与仿真结果表明:单个立体均压结构,相比于雷电注入点,地电位下降了约41.67%;多层立体均压结构,最外层地电位下降了约45.5%。

When the wind farm is hit by lightning, the grounding resistance of the traditional grounding device is too large and the soil penetration of the lightning current in the vertical direction is weak, which will lead to the uneven distribution of impulse potential and the increase of local potential. A new three-dimensional voltage-sharing structure is proposed to increase the vertical discharge capacity of lightning current and improve the gradient of ground potential. As the results of theoretical calculation and simulation show, compared with the lightning injection point, the ground potential of a single-layered solid voltage-sharing device decreased by 41.67%;the ground potential of the outermost layer of a multi-layered solid voltage-sharing device decreased by about 45.5%.