传输线路感应雷防护计算方法的研究

Computing Method Research for Induced Voltage Protection of Transmission Lines

感应雷电压对低压输电线路造成的影响不可忽视。对感应雷电压、雷电流的波形、幅值、陡度及传播过程进行了全面分析 ,并对感应雷的危害性作出评估。由于对感应雷跳闸率的计算不能象直击雷那样给出等值受雷宽度 ,故利用击距理论确定雷电流引起闪络的有效距离范围 ,而利用雷电流概率函数对雷电流积分求出感应雷跳闸率。

The influence of induced voltage due to lightning is not negligible in low-voltage systems. This paper includes a full analysis of the waveform, peak value and rate of increase of induced voltage, and evaluates its destructive features. The difficulty in calculating the fault rate caused by induced lightning voltage is to find an effective width equivalent to the width of direct strikes, in which a flashover can be triggered. Using the methods of striking distance theory, first, the effective width of each lightning current can be found. Then, with the lightning current probability density function, the dropout rate caused by induced voltages can be obtained by integrating over all lightning currents.