架空配电线路雷击闪络率改进算法

The Improved Calculation Method of Lightning Strike Flashover Rate for Overhead Distribution Lines

配电线路雷击闪络率作为线路跳闸、断线等故障的前提,能够对线路可能引起的跳闸、线路断线等故障风险做初步评判,可有效表征配电线路耐雷性能。目前,对于配电线路受雷宽度的计算套用输电线路的计算方法,不符合配电线路实际情况。笔者依据静电场理论分析定义了线路等效闪络宽度,该值综合考虑了雷电流幅值、线路高度和线路耐雷水平等参数的影响,相较于输电线路等效引雷宽度的算法更加全面、准确;提出了基于配电线路电气几何模型的线路闪络率改进算法,并计算了典型10 kV配电线路的雷击跳闸率,通过与实际统计值进行比较,验证了该方法的准确性。

Lightning flashover rate of distribution line is the premise of line tripping and disconnection.It can make a preliminary judgment on these faults,which can effectively represent the lightning protection performance of distribution lines.At present,the lightning width of the distribution line is calculated by the method of transmission line,which does not satisfy the actual situation of the distribution line.The equivalent flashover width of the line is defined in this paper,taking into account the influence of lightning current amplitude,line height and lightning protection performance.It is more comprehensive and accurate than the equivalent lightning-throwing algorithm of transmission line.The line flashover rate improvement algorithm based on the electrical geometry model of the distribution line is used,and the lightning trip rate of the typical 10 kV distribution line is calculated.The accuracy of the method is verified by comparison with the actual statistics.