高杆塔大跨越输电线路防雷保护

Lightning Protection Performance of Transmission Line with High Tower and Great Span

对跨海特高塔大跨越段的耐雷性能进行了研究 ,提出了高塔大跨越段输电线路雷电屏蔽模型。该模型模拟了雷电先导向下发展的过程 ,并考虑了上行先导对下行先导的影响 ,仿真模型中包括了“回头雷击”的情况 ,即有可能出现的当下行雷电先导已经下降到低于输电线路高度时还发生雷击导线的情况。针对某海上大跨越段输电线路采用规程法、击距法和本文提出的模型分别计算其耐雷性能 ,并对计算结果进行了分析比较。由于考虑了“回头雷击”的情况 。

This paper studies lightning protection performance of transmission line with high tower and great span, and puts forward the lightning shielding model of transmission line with high tower and great span. The model simulates the developing process of lightning downward leader, and take the effect of upward leader to downward leader into account. Moreover, the model consider backward lightning , that is even downward leader have developed lower than transmission line, Which will be occur lightning line. Aim at a certain sea transmission line with great span, its lightning performance is calculated with regular method, EGM and the model. The results have been analysed and compared. Because of thinking over backward lightning , the model can be used for calculating lightning shield performance of all kinds of transmission lines.