城市轨道交通钢轨电位过高问题的研究

Research on over High Issue of Rail Potential in Urban Rail Transit

城市轨道交通中,钢轨作为主要回流导体,钢轨电位过高对设备以及人员造成严重影响。针对某地铁线路的钢轨电位过高的问题,文中在长区间钢轨对结构钢筋过渡电阻测量方法的基础上,对该线路进行钢轨对地过渡电阻评估。测试结果表明地下段过渡电阻仅为1.816Ω·km,远小于标准规定要求。为分析该绝缘缺陷对钢轨电位问题的影响,文中基于线路实际情况,结合交直流混合迭代方法,进行了牵引供电计算仿真,分析钢轨过渡电阻分布对钢轨电位问题的影响,该线路过高的钢轨电位问题与地下区段过低的过渡电阻有直接关系。

Rails return current lead to potential in rail urban rail transit and its high rail potential has a serious impact on equipment and personnel.The rail potential of some lines is too high.A method for measuring the rail to structural reinforcement transition resistance of long section is proposed,and the full coverage test of the line is carried out.The test results show that the transition resistance of underground section is only 1.816Ω·km,which is less than the value specified in the standard.In order to analyze the influence of the insulation defect on rail potential,the traction power supply calculation simulation is carried out based on the actual line situation.The simulation is combined with AC/DC hybrid iterative method.Through analysis of influencing factors and rail potential mechanism,the findings are the high rail potential directly related to the low transition resistance in the underground section.