城市轨道交通轨地过渡电阻对杂散电流分布特性的影响  

Influence of Rail-to-ground Resistance of Urban Transit Systems on Distribution Characteristics of Stray Current

作　　者：朱峰[1] 李嘉成[1] 曾海波 邱日强 ZHU Feng;LI Jiacheng;ZENG Haibo;QIU Riqiang(School of Electrical Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学电气工程学院

出　　处：《高电压技术》2018年第8期2738-2745,共8页High Voltage Engineering

基　　金：国家自然科学基金(U1434203)~~

摘　　要：为研究城市轨道交通轨地过渡电阻对杂散电流的影响,基于电阻网络的方法,建立将各金属结构、道床及大地等效成电阻和过渡电阻的电路模型,并推导出各金属结构电压、电流的解析表达式。然后采用CDEGS软件作了仿真验证,讨论了不同过渡电阻及区间过渡电阻不均匀对杂散电流和走行轨电位的影响。研究结果表明：过渡电阻均匀和不均匀时,仿真结果均与计算值基本保持一致;过渡电阻均匀时,排流网电位最大偏差为5.7 m V,不超过16%;轨地过渡电阻与走行轨绝缘电阻率成正比,杂散电流大小与过渡电阻成反比,过渡电阻为3？·km时,杂散电流达到1 448.4 m A;不均匀过渡电阻并不会影响走行轨上的压降,但会改变其电位分布;过渡电阻突变减小会增大总杂散电流。研究成果可为地铁杂散电流防护设计提供依据。To research the influence of rail-to-ground resistance of urban transit systems on stray current, by using the method of resistance network, we established a circuit model that each metal structure, ballast bed and ground are equivalent to resistance and rail-to-ground transition resistance. The formulations of voltage and current of each metal structure were derived. An inspection was conducted by using the CDEGS Software, and stray current and rail potential under different rail-to-ground resistance and non uniform track-to-earth resistance were discussed. The results show that the calculations remain nearly the same as simulation results with both uniform and non uniform rail-to-ground resistances. When the track-to-earth resistance is homogeneous, maximum potential deviation of stray current collection mat is 5.7 m A, which is no more than 16%. The rail-to-ground resistance is directly proportional to the insulation of rail, and the stray current is inversely proportional to the track-to earth resistance. The total stray current can reach 1 448.4 m A when the rail-to-ground resistance is 3 ？·km. The nonuniform rail-to-ground resistance will change the distribution of rail potential, but the rail voltage drop will remain unchanged. Furthermore, a sudden reduction of the rail-to-ground resistance will increase the total stray current. The results can provide a basis on which a protective system of stray current in metro is designed.

关 键 词：杂散电流 电阻网络 过渡电阻 CDEGS 走行轨 

分 类 号：U231.8[交通运输工程—道路与铁道工程]