1000kV交流特高压输电线路的防雷保护

利用研究输电线路雷电性能的自编程序LLPP,对UHV输电线路的雷电性能进行研究。介绍了对UHV输电线路避雷线屏蔽性能的研究结果和改进建议,并对UHV输电线路雷电反击耐雷性能进行计算。交流特高压输电线路的运行经验表明:特高压输电线路仍有相当的雷击闪络跳闸,初步分析是因避雷线屏蔽失效而致;杆塔较高和导线上工作电压幅值大,可能是较重要的因素。在工程设计中,对耐张塔和转角塔也要专门研究,使其具有较少的保护角。对于山区,因地形影响(山坡、峡谷),避雷线的保护可能要取负保护角,这些有待于进一步研究,从而保证我国特高压输电线路具有较好的雷电性能。交流特高压输电线路杆塔上较高的绝缘强度,使其具有良好的承受雷电反击的能力。

Lightning protection of AC 1 000 kV UHV transmission line

The Lightning performance of UHV transmission line was presented by using program LLPP. The study results of shield performance for overhead ground line of UHV transmission line were put forward, and some improving methods were recommended. The study results of lightning back flashover for the UHV transmission line were also presented in this paper . The operating experience of other UHV overhead transmission lines showed that UHV lines have certain lightning stroke tripout rate, the reason for which is shielding failure according to the primary analysis. The higher tower height and larger system voltage may be important factors. In design of shielding angles, the tension tower and the corner tower also should be specialized, making sure they have lesser shielding angles. For mountainous areas, because of the influence of landform, especially hilltop and gorge, shielding angles may be negative angle, which needs further research to ensure the great lightning performance of UHV overhead transmission lines in China . The higher insulation level of UHV overhead transmission lines makes the stronger lightning performance against back flashover of lines.