高原山地500kV输电线路雷电屏蔽特性试验研究

Research on Lightning Shielding Characteristics of 500 kV Transmission line in Plateau Mountain

运行经验表明,雷电绕击是引起220kV以上电压等级输电线路雷击跳闸的主要原因,为了更好地了解500kV输电线路空间各个落雷点的绕击概率分布情况以及避雷线保护角对屏蔽性能的影响,以贵州500kV典型输电线路为研究对象,通过对缩小的输电线路杆塔模型进行空间绕击屏蔽模拟试验,研究结果验证了负保护角在防绕击性能上的优越性,研究表明:距离输电线路越近绕击空间越大,且从塔头至档距中央,绕击概率的变化规律是先增加,后减少。研究成果为500kV输电线路的防雷设计提供了科学依据。

In order to better understand the probability distribution of space around the each lightning point and influences of ground wires protection angular of the 500 kV transmission line on the shielding performance, using the 500 kV typical transmission lines as examples, we established a model of reducing transmission line tower to simulate the shielding failure. The experimental results verify the superiority of the negative protection angle in the antishielding performance, and reveal that, the closer the transmission lines are, the more the strike is; from the central tower head to file, the probability of shielding failure increases first, then decreases. The research results provide a scientific basis for the design of lightning protection of 500 kV transmission lines.