基于分段传输线模型的同杆双回线路反击耐雷性能研究

为了更准确的计算超高压输电线路的反击耐雷性能,给出了同杆双回线路杆塔的分段传输线模型。利用EMTP程序对同杆双回500kV输电线路的反击耐雷性能进行了计算和分析,考虑到雷击塔顶时导线上工频电压的随机性,采用统计法确定超高压线路的反击耐雷性能。计算结果表明:采用本文介绍的分段传输线模型进行计算,在杆塔接地电阻相同时,塔顶电位低于单一波阻抗模型,并且与后者相比,塔顶电位受接地电阻影响更小;和单一波阻抗杆塔模型相比,采用分段传输线模型进行计算得出的耐雷水平更高,耐雷水平受接地电阻的影响更大。

Study on the Lightning Protection Performance of Back Striking for Double-circuit Transmission Line Based on Distributed Line Tower Model

In order to make the calculation of the lightning protection on ultra high voltage more precisely than the traditional methods,a distributed line tower of Double-circuit Transmission Line is constructed.The light- ning protection pedormance of back striking for an AC 500 kV double-circuit transmission line by EMTP is de- tailed in this paper.A statistical method is brought forward with considering the randomness of working voltage 's phase in the case of lightning striking the top tower.By contraries,the tower parameter changing with height is considered in the distributed line tower model,so the results are more precise than those of the other two models.