The stray current from the DC-electrified traction system can affect the pipeline-to-soil potential and can cause corrosion on the buried pipeline, which will bring about economic losses and even threaten personal safety. Thus, it is necessary to study the stray current generated by the rail potential and its impacts on pipeline corrosion. For this purpose, an analysis approach, in which the theoretical method is used in combination with the finite element model and experimental analysis, is presented. The dynamic distribution equations of the rail potential and the stray current are deduced by using a mathematical model. A finite element model based on the theoretical equations is established to calculate the pipeline-to-soil potential under the interference of the stray current from the running rails. Finally, the obtained pipeline-to-soil potential is used as voltage interference to develop an electrochemical experiment and the variation laws of the electrochemical impedance spectroscopy of the pipeline metal are studied by using this experiment. The theoretical results show that the stray current is proportional to the rail potential. The pipeline-to-soil potential under the interference of different stray current can be expressed as a sine function according to the fitted results of the finite element analysis. And the coefficients of the function are determined by the relative position of the pipeline and the running rails. Meanwhile, the coefficients of the function (amplitude, frequency, and offset) have different influence on the EIS of the pipeline metal.

直流电牵引系统产生的杂散电流会影响管道到土壤的电势，并可能对地下管道产生腐蚀，这将带来经济损失，甚至危及人身安全。因此，有必要研究轨道电位产生的杂散电流及其对管道腐蚀的影响。为此，提出了一种将理论方法与有限元模型和实验分析相结合的分析方法。利用数学模型推导了轨道电位和杂散电流的动态分布方程。建立了基于理论方程的有限元模型，以计算在运行轨道产生的杂散电流的干扰下管道对土壤的电势。最后，将获得的管线对土壤电势作为电压干扰进行电化学实验，并通过该实验研究了管线金属电化学阻抗谱的变化规律。理论结果表明，杂散电流与电源电压成正比。根据有限元分析的拟合结果，可以将不同杂散电流干扰下的管道对土壤电势表示为正弦函数。函数的系数由管道和运行轨道的相对位置确定。同时，函数的系数（振幅，频率和偏移）对管道金属的EIS具有不同的影响。