基于波导反射系数的输电线路杆塔回击电流变化趋势研究

Study on Variation Trend of Transmission Line Tower Return Stroke Current Based on Waveguide Reflection Coefficient

针对目前对杆塔不同位置处回击电流变化差异性研究相对较少的现状,主要采用雷击杆塔回击工程模型、双Heidler回击电流源模型,首先研究杆塔不同位置处回击电流变化特征,其次研究不同杆塔高度对塔底电流的影响,最后研究在不同波导反射系数情况下,塔底电流变化差异性。研究表明:回击电流在杆塔不同位置处的差异性较大,塔底回击电流峰值较塔顶高出33%;随着杆塔高度的增加,塔底回击电流振荡特征越显著;塔底回击电流峰值与塔底波导反射系数呈正相关,反射系数增大2倍,塔底回击电流峰值提高14.3%。

In view of the current situation that there are relatively few studies on the difference of the strikeback current change at different positions of the tower,the lightning strike tower strikeback engineering model and the double Heidler strikeback current source model are mainly used.Firstly,the variation characteristics of the swirl current at different positions of the tower are studied.Secondly,the influence of different tower heights on the current at the bottom of the tower is studied.Finally,the variation of the current at the bottom of the tower is studied under the condition of different waveguide reflection coefficients.The research shows that the recoil current varies greatly at different positions of the tower,and the peak value of the recoil current at the bottom of the tower is 33%higher than that at the top of the tower.With the increase of the height of the tower,the oscillation characteristics of the return current at the bottom of the tower are more significant.The peak value of the recoil current at the bottom of the tower is positively correlated with the reflection coefficient of the waveguide at the bottom of the tower,the reflection coefficient increases by 2 times,and the peak value of the recoil current at the bottom of the tower increases by 14.3%.