地铁牵引系统对地表电位影响时域仿真  

Time Domain Simulation of the Influence of Metro Traction System on Ground Potential

作　　者：吴泳聪 蔡汉生 胡上茂 张义 WU Yongcong;CAI Hansheng;HU Shangmao;ZHANG Yi(State Key Laboratory of HVDC Technology,Electric Power Research Institute,CSG,Guangzhou 510663,China;School of Electric Power Engineering,South China University of Technology,Guangzhou 510641,China)

机构地区：[1]直流输电技术国家重点实验室(南方电网科学研究院),广州510663 [2]华南理工大学电力学院,广州510641

出　　处：《南方电网技术》2023年第6期80-89,共10页Southern Power System Technology

基　　金：国家自然科学基金资助项目(52277158)。

摘　　要：为了掌握地铁牵引系统引起交流电网直流偏磁的机理,以地表电位为对象,开展地铁牵引系统对临近地表电位影响的时域仿真研究。首先建立了包含轨道、轨-地过渡电阻、隧道、结构钢筋及排流网的地表电位时域仿真模型,随后利用上述模型模拟了列车出站、列车进站、多列车同向运行、多列车上下行运行等工况下所产生的地表电位时域波形。结果表明,偏磁电流与地表电位的时变性源于牵引电流与杂散电流的时变性,且地表电位大小、极性及达到峰值的时刻同时受到列车、观测点、牵引站之间相对位置的影响;多辆列车运行时,当运行间隔增大,各列车产生的地表电位的叠加作用减弱,地表电位时域波形表现为“间歇性”振荡,反之,运行间隔减小,各列车产生的地表电位的叠加作用增强,地表电位时域波形表现为“连续性”振荡;此外,当上下行列车同时进出站时,可能引起地表电位的局部较大脉冲。综上所述,地铁牵引系统时变的地铁牵引电流、列车位置、运行间隔、数量、运行状态等因素共同作用是造成直流偏磁电流及其产生电位极性、峰值与振荡频率变化的主要原因。最后,通过试验实测对仿真模型与所得结论进行了验证。In order to study the DC bias mechanism of AC power grid caused by metro traction system,this paper takes the ground potential as the object,and carries out time-domain simulation about the influence of metro traction system on the adjacent ground potential.Firstly,the time domain simulation model of ground potential including rail,rail-ground transition resistance,tunnel,structural reinforcement and drainage network is established.Then,the time domain waveforms of ground potential under different conditions are simulated which include metro departure,metro arrival,metros running in the same direction and metros running in the opposite direction.Results show that the time variation characteristics of DC bias current and surface potential originate from the time variation of traction current and stray current,and the magnitude,polarity and peak time of surface potential are affected by the relative position among metro,observation location,and traction station;When multiple metros are considered,the superposition ef⁃fect of ground potential generated by each metro decreases as the running interval increases,and the time domain waveform of ground potential shows intermittent oscillation.On the contrary,the superposition effect of ground potential generated by each train increases when the running interval decreases leading to continuous oscillation of ground potential.Moreover,large pulses of surface potential may appear if two metros enter or leave the station simultaneously.In conclusion,the time-varying traction current,train position,operation interval,quantity,and operation state of metros are the main causes for the change of polarity,magnitude,and oscillation frequency of DC bias current and potential.Finally,the simulation model and results are verified by measurement.

关 键 词：地铁牵引系统 地表电位 交流电网 直流偏磁 时域仿真 

分 类 号：TM41[电气工程—电器]