1 000 kV双回路多根地线防雷研究

为了使特高压双回输电线路更加安全可靠地运行,以国内某1 000 kV交流输电线路工程SZC301型双回直线塔和SJC301型双回耐张塔为研究对象,提出了相邻耐张塔如何与双回直线塔多根地线配合的方案,综合分析了双回直线塔关于I型悬垂串和V型悬垂串的不同排列组合对导线与多根地线间距的影响。双回直线塔中层横担改挂V型悬垂串,下层横担加挂地线,可使塔头处中、下相外侧子导线的静态防雷保护角较常规分别减少11°和15°,上、中、下相外侧子导线动态防雷保护角分别为-11°、-20°和-9°,有效地减少了山区的地形坡度对绕击率的影响。

Study on Lightning Protection by Multi-band Grounding Wires for 1000-kV Double-Circuit Lines

In order to make the UHV double-circuit transmission lines run safer and more reliable, a scheme was proposed for neighboring tension tower’s coordination with multi-band grounding wires on double-circuit tangent tower by taking the SZC301 double-circuit tangent tower and SJC301 double-circuit tension tower of one domestic 1 000 kV AC transmission line project as a case study. The influence of different arrangement and combination of “I” string and“V” string of double-circuit tangent towers were synthetically analyzed on the interval between conductor and multi-band lightning wires. If the “V” string is hung up in the middle cross-arm on double-circuit tangent tower, and one lightning wire is hung up in the lower cross-arm, the static lightning protection shielding angle of the middle outer sub-conductor and lower outer sub-conductor on the tower head will be reduced by 11°and 15° respectively, and the dynamic lightning protection shielding angle of the three (upper, middle and lower)-phase outer sub-conductors are -11°and -20°and -9° respectively, which has effectively reduced the influence of the terrain slope on shielding failure rate.