喷射气流灭弧条件下输电线路雷击跳闸率计算方法

Calculation Method of Lightning Trip-out Rate of Transmission Line Under Jet Stream Arc-extinguishing Condition

喷射气流灭弧防雷间隙是一种以抑制绝缘建弧为目标的主动灭弧防雷方式。为了计算喷射气流灭弧条件下输电线路的雷击跳闸率,首先通过实验统计及概率分析确定了喷射气流灭弧条件下近似理想的建弧系数(约为0.02)以及建弧率计算式,然后基于规程法建立了相应的雷击跳闸率计算模型,最后选取了典型35 k V线路进行算例验证。理论计算表明线路在平原和山区的年平均雷击跳闸率能够分别下降到0.380 8次/(100km?a)和0.384 2次/(100km?a),下降比例分别为95.53%和96.06%。在实际运行中上述两者能够分别下降到0.530 3次/(100km?a)和0.564 1次/(100km?a),下降比例分别为93.78%和94.21%。以上两方面的分析结果基本一致,初步验证了理论计算方法的有效性以及喷射气流灭弧防雷间隙的运行效果。

Jet stream arc-extinguishing lightning protection gap（JSALPG） is an initiative arc-extinguishing lightning protection method aiming at suppressing insulator arc-establishing. In order to calculate the lightning trip-out rate under jet stream arc-extinguishing（JSA） condition, firstly, we acquired an approximate ideal arc-establishing coefficient（about 0.02） and the arc-establishing rate formula under JSA condition by experimental statistics and probability analysis. Secondly, we established the calculation models of lightning trip-out rate under JSA condition by using the regulations method. Finally, we selected a typical example of 35 k V line for verification. The theoretical calculation results show that the annual average lightning trip-out rate at plain and mountainous area of this line have dropped to 0.380 8 and 0.384 2 times/（100km·a）, respectively, and the drop ratios are 95.53% and 96.06% respectively. The practical operation results show that the above two factors have dropped to 0.530 3 and 0.564 1 times/（100km·a）, respectively and the drop ratios are 93.78% and 94.21%, respectively. The results above preliminarily verify that the validation of theoretical calculation method and the operation effect of JSALPG.