直流接地极引起的高速铁路综合接地系统直流电流计算

DC Current Calculation of High⁃speed Railway Integrated Grounding System Caused by HVDC Grounding Electrode

随着我国高速铁路的广泛延伸,直流接地极与高速铁路相接近的情况时有发生。直流接地极入地电流可能会对高速铁路综合接地系统造成影响。为了评估直流接地极对高速铁路综合接地系统的影响情况,文中建立了高速铁路综合接地系统的直流电流分布的分析模型,获得了高速铁路沿线轴向直流电流分布和单位长度泄漏电流密度分布,说明了直流接地极对高速铁路综合接地系统的电腐蚀影响机理,并分析了土壤电阻率、直流接地极距离等因素对电腐蚀程度的影响。研究结果表明,直流接地极对高速铁路综合接地系统有一定的电腐蚀影响,应重点关注距离直流接地极较近并处于高土壤电阻率地区的高速铁路线路的电腐蚀情况。

With the extensive extension of high⁃speed railway in China,the situation that the DC grounding elec⁃trode is close to the high⁃speed railway often occurs.The grounding current of DC grounding electrode may affect the integrated grounding system of high⁃speed railway.In order to evaluate the influence of DC grounding electrode on the integrated grounding system of high⁃speed railway,the analysis model of DC current distribution in high⁃speed railway integrated grounding system is setup in this paper.The distribution of axial DC current and leakage current density distribution per unit length along the high⁃speed railway is obtained.The influence mechanism of DC grounding electrode on the electric corrosion of high⁃speed railway integrated grounding system is explained.The in⁃fluence of such factors as soil resistivity and DC grounding electrode distance on the degree of electric corrosion is analyzed.It is shown by the study result that the DC grounding electrode has certain electrical corrosion impact on the integrated grounding system of high⁃speed railways.Attention should be paid to the electric corrosion of high⁃speed railway lines which are close to the DC grounding electrode and located in the area with high soil resistivity.