高压直流导线单点电晕无线电干扰的瞬态计算方法  

Transient Method for Calculating Radio Interference Due to Single-point Corona on HVDC Lines

作　　者：刘阳[1] 崔翔[1] 卢铁兵[1] 

机构地区：[1]华北电力大学新能源电力系统国家重点实验室,北京102206

出　　处：《高电压技术》2013年第12期2972-2979,共8页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2011CB209402);国家自然科学基金(51177041);教育部中央高校基本科研业务费专项资金(12QX01)~~

摘　　要：电晕产生无线电干扰预测是高压直流线路设计中的一个重要内容。为此,提出了1种计算这种干扰的瞬态计算方法。首先搭建了直流导线单点电晕放电试验平台,获得了电晕电流脉冲以及脉冲序列的波形。基于这些波形的特点,利用BLT(Baum-Liu-Tesche)方程对电晕电流沿导线的传播过程建立了计算模型。进而基于矩量法建立了场的计算模型,实现了无线电干扰的时域计算。通过与商业软件FEKO的比较验证了该计算方法的准确性。利用该方法对一典型算例进行了计算,结果表明:土壤电阻率和导线长度对无线电干扰的时域特性有较大影响。当土壤电阻率由100Ω·m增加到1 000Ω·m时,无线电干扰电场分量增加了约10倍;土壤电阻率由100Ω·m增加到500Ω·m时,无线电干扰磁场分量增加了约2.5倍,而土壤电阻率由500Ω·m增加到1 000Ω·m时,无线电干扰磁场分量基本上不变;无线电干扰的谐振频率与导线长度成反比。Prediction of radio interference （RI） induced by corona on transmission lines is one of the important issues for designing HVDC transmission projects, so we proposed a transient method for calculating RI. Firstly, we established an experimental platform of single-point corona on DC line, through which we obtained the waveforms of corona current pulses and pulse train. Then, based on the time-domain characteristics of these corona pulses, the propagation of corona current along the conductor was analyzed and its calculation model was established using Baum-Liu-Tesche equations. Finally, using the obtained current distribution, we established a model for calculating the electromagnetic fields of RI and realized the calculation of RI in time domain. A comparison with results obtained by the commercial software FEKO verified the accuracy of the proposed method. Moreover, we calculated the transient characteristics of RI by taking a typical case as an example. The results show that ground resistivity and conductor length have considerable influences on RI： as the ground resistivity increases from 100 Ω·m to 1 kΩ·m, the electric field component of RI increases by about ten times; the magnetic component of RI increases by about 2.5 times with an increase of ground resistivity from 100 Ω· m to 500 Ω· m, but it shows little difference when the resistivity increases from 500 Ω·m to 1 kΩ·m; the resonance frequency of RI is inversely proportional to conductor length.

关 键 词：高压直流输电 单点电晕 电晕电流 BLT方程 矩量法 无线电干扰 

分 类 号：TM751[电气工程—电力系统及自动化]