输电线路杆塔接地装置冲击系数及其拟合计算公式

选择合适的冲击系数是输电线路杆塔接地装置设计的关键。采用模拟试验分析了各种因素对冲击系数的影响。大量的试验结果表明，冲击系数随冲击电流幅值的增加而减小；随接地体几何尺寸的增加而增加；随土壤电阻率增加而减小。本文通过对试验数据进行回归分析，得出了计算不同接地装置的冲击接地系数的经验公式。模拟试验得到冲击系数值与文献中提供的现场实测结果吻合得较好。研究成果可以为输电线路杆塔接地装置的设计和修订接地规程提供参考。

Characteristics and fitting formula of impulse coefficient of grounding device of transmission-line

Impulse coefficient of grounding device is a key parameter of lightning protection design of transmission lines. The influences of different factors on the impulse coefficients of grounding devices were discussed by simulation experiments. Based on analyzing a large amount of experimental results. It is obtained that the impulse coefficient reduces with the increasing of impulse current magnitude, geometrical dimension of grounding device and soil resistivity. The fitting formulae of impulse coefficient were acquired by regressive analysis to experimental results. The simulating experimental results had a good agreement with those of field experiment in literature. The research results could be applied in grounding device design of transmission line, and could be very useful in the modification of grounding standard.