高海拔高风速情况下特高压直流输电线路离子流场计算与测量研究

Calculation and measurement of ion flow field of UHVDC transmission line at high altitude and high wind speed

在特高压直流输电线路离子流场的求解中,对于高海拔高风速情况下采用传统算法计算时存在一定偏差,本文研究了高海拔条件对导线起晕场强的影响机理,并基于风速分布规律模型,使用有限元法求解特高压直流输电线路离子流场。本文选择云广±800 kV特高压直流输电线路昆明段作为试验线路,通过试验测量了线路下方的地面合成电场与离子流密度;根据国标规定选择测量设备,并给出了试验中测量点的选择、测量设备布置以及数据采集的方式。据误差分析,数值计算结果与试验数据一致性较好,验证了本文算法的可靠性。同时,分析了风速对地面离子流场分布情况的影响,研究结论表明特高压直流输电线路在高海拔与高风速条件下地面合成电场与离子流密度有超过安全值的风险。

In the calculation of ion flow field of Ultra High Voltage Current(UHVDC)transmission line under the conditions of high altitude and high wind speed,there might be some deviations by traditional ways.This paper studies the influential mechanism of high altitude on the wires corona inception electric field,based on the wind speed distribution model,using Finite Element Method to calculate the ion flow field.In this paper,Kunming sec-tion of Yunguang±800 kV UHVDC transmission line is selected as the experiment line,and the ground total elec-tric field and ion current density under the line are measured experimentally.The selection of measuring equipment complies with national standards,and the selection of measuring points,the layout of measuring equipment and the way of data collection in the experiment are given.According to the error analysis,the measured data is consistent with the calculation results.How the factors of wind velocity influence the ion flow field herein are analyzed as well.What this paper concludes is that the ground total electric field and ion current density might exceed the safe value when the UHVDC transmission lines are under the conditions of high altitude and strong wind.