架空线路雷电感应过电压估算与分析

根据雷击时雷电电磁场作用于架空线路的特点,通过建立计算模型推导出雷击点距架空线路任意位置的雷电感应过电压估算公式,对架空线路高度、架空线路距雷击点距离、架空线路旁被雷击物体的高度,以及上升先导长度等各类参数对雷电感应过电压的影响进行了分析,研究了与DL/T620-1997＂交流电器装置的过电压保护和绝缘配合＂标准中架空线路上的雷电过电压估算公式的关系,试图为建筑物内电子和电气设备损坏的原因进行定量分析以及更好地进行线路上的雷电防护设计提供帮助。

Computation and Analysis of Lightning-Induced Overvoltages in Overhead Lines

According to the characteristics of the action of the lightning electromagnetic field on overhead lines, the relation formula is devised between the position of any given strike point and the lightning induced overvoltage along an overhead line by mathematics models. The influences on lightning induced overvoltage are analyzed of such factors as the height of an overhead line, the distance between overhead line and strike point, the height of an object beside the overhead line, the length of a raising leader (return stroke), etc. The relationship between new formula and the formula from the standards DL/T620 1997 (Overvoltage Protection and Insulation Coordination for AC Electrical Installations) is given, aiming to identify the causes of electronic and electrical equipment damages quantitatively to provide reference for lightning protection design.