一种提高输电线路空气间隙绝缘强度方法的研究

Method study on improving dielectric strength of air gap of transmission lines

为有效提高输电线路空气间隙绝缘强度,降低线路风偏闪络故障率,本文首先采用典型棒-板电极,开展了绝缘屏障条件下的间隙击穿试验,提出了加装绝缘屏障提高间隙击穿电压的基本方法,然后基于该方法,结合杆塔间隙试验数据,提出了特高压交流输电线路杆塔空气间隙的绝缘屏障参数。研究表明,在零电位电极处安装绝缘屏障,能够阻碍放电通道的形成,并增加间隙放电通道长度,可提高间隙的击穿电压;特高压杆塔应用绝缘屏障,可以提高杆塔间隙绝缘强度,减小塔头设计,是一种具有实用价值的输电线路优化设计和运维技术。

In order to improve the insulation strength of power transmission line air-gaps effectively and reduce failure rate of flashovers caused by windage yaw in transmission lines,typical rod-plane electrode was adopted and power frequency discharge tests with insulation barriers were carried out. A method of installing insulation barrier was discovered to increase the breakdown voltage,and then the parameters of insulation barriers for improving the insulation strength of air gaps between transmission lines and towers were put forward according to the test data. Results show that,the method of installing insulation barrier on the surface of zero potential electrodes will hinder the formation of discharge channel,increase the length of the air-gap discharge channel,and the breakdown voltage can be increased. Installing insulation barrier on the surface of tower can increase the conductor-tower gap insulation strength of UHV AC transmission line,reduce the design parameters of tower head,and it is a practical technique for optimization design and maintenance.