同塔四回输电线路多回同时闪络耐雷性能及防治

Lightning Protection Performance of Multi-circuit Flashover Simultaneously and Its Prevention for Quadruple-circuit Transmission Lines in a Tower

为了更加科学有效地防范雷击同跳故障,根据雷击闪络绝缘子串放电发展的物理过程,在电磁暂态程序(EMTP)中建立了同塔四回输电线路雷击闪络模型。在考虑系统工作电压的情况下采用线路耐雷性能实际考量指标,研究了同塔四回线路雷击同跳闪络特性及相序排列、耦合地线等防雷措施的配置方式对线路耐雷性能的影响。结果表明,线路耐雷水平随系统电压相位角以近似非标准的正弦波波动;对同塔四回线路采用完全逆相序排列方式,其单回、双回闪络耐雷性能最佳;在塔顶架设耦合地线对提高线路耐雷性能比在塔底效果更好。

In order to prevent the multi-circuits transmission lines from lightning trip-out simultaneously more scien tifically and effectively, the lightning flashover model for quadruple-circuit transmission lines in a tower was established in EMTP based on the physical process of discharge development of insulator that was struck by lightning. Taking the influ- ence of system working voltage into account by adopting the actual evaluation index of lightning protection performance, the characteristics of lightning trip-out simultaneously {or quadruple-circuit line in a tower was studied, as well as the im- pacts on lightning protection performance caused by the configuration mode of lightning protection measures including phase sequence arrangement, coupling ground wire and so on. The results show that the lightning withstand level fluctu- ates with phase angle in the shape of non-standard sinusoidal wave approximately; the lightning withstand level comes to the best under the complete reverse phase sequence; the effect of coupling ground wire on the top of tower is preferable to that on the bottom of tower.