地面上接地金属体高度对雷击选择性的影响

鉴于雷闪放电中地面接地物体高度是雷电通道走向的影响因素之一,简析了接地金属体高度对雷击选择性的影响。根据雷电发展的梯级性推导出下行雷电通道的模型,用等效电荷代替雷电通道所有电荷量,研究了在该电荷作用下两个接地金属体的感应电荷及其电场分布。根据雷击路径方向与场强最大方向一致的原理,用例子计算金属体所受的雷击范围,结果表明接地金属体越高及放电通道与金属体水平距离越近,雷击概率越高。

Influence of Height of Grounding Conductors Above Ground on Lightning Strike Selectivity

During the lightning discharge, the height of the grounding conductor is the one of the factors affecting lightning path. In the article, the relationship is simply analyzed between the height of the grounding conductors and lightning strike selectivity. According to the step of lightning development, the model of the downward lightning channel is got. An equivalent charge is used to represent the whole charge in the discharge channel. Charge distribution in two grounding conductors is studied under the induction of the charge. Based on the principle that both the lightning path and the largest electric field are in the same direction, the lightning strike area in the conductors is calculated by a sample. The higher the conductors are, the nearer the lightning channel is to the conductors, the possibility of lightning strike is largely increased.