特高压输电线路树障隐患预判及仿真分析

UHV Line Tree Barrier to Predict the Rsk of Transmission and Simulation Analysis

针对输电线路树障隐患的研究,主要在于树冠距架空导线的净空距离和间隙绝缘特性两方面.以云-广特高压直流输电线路为研究对象,结合当地的气象条件和立地信息,分别建立导线下方树障隐患预判模型和导线旁树障隐患预测模型.利用Richard方程,建立树高生长预测模型作为树障的动态边界条件.运用解析法计算树冠距导线空间畸变电场,与线路间隙最小击穿场强进行比较,对是否发生树闪故障进行预判.通过Ansoft软件,对导线距树冠空间电场分布进行仿真分析.由分析可得,树高为18.591 m的树木畸变电场强度为662 480.043 V/m,线路间隙最小击穿电场强度为38 230 V/m,树冠处畸变电场强度远大于击穿场强,严重威胁线路安全运行对树障隐患作出提前预判.

The research on the hidden trouble of the transmission line is mainly due to the clearance distanceand the gap insulation characteristic of the crown from the overhead line. In this paper,the cloud-wide special-purpose HVDC transmission line is taken as the research object. Combined with the local meteorological condi-tions and site information,the forecasting model of hidden trouble and the hidden danger forecast model of thetrail next to the wire are established respectively. Using the Richard equation,the tree height growth predictionmodel is established as the dynamic boundary condition of the tree barrier. The spatial distortion electric fieldof the crown is calculated by using the analytical method,and the minimum field breakdown field strength ofthe line gap is compared to judge whether the tree flash fault occurs. Ansoft software is used to simulate thedistribution of electric field from the canopy space. The intensity of the distorted electric field is 662 480. 043V/ m,the minimum breaking strength of the line gap is 38 230 V/ m,the distortion intensity of the crown ismuch larger than that of the breakdown field,which seriously threatens the safe operation of the line. On thehidden danger of the tree made in advance to predict.