A Method of Defect Diagnosis for Integrated Grounding System in High-Speed Railway

An integrated grounding system (IGS) plays a significant role in reliable operations of a high-speed railway (HSR). The defect problems of grounding conductors have been frequently occurring due to the long-time service of an IGS and the large current from a traction system. Therefore, defect diagnosis should be conducted. Considering the topology of an IGS and the distribution feature of the surface potential, a method is proposed here to diagnose and locate the defect of the IGS. The grounding conductors can be classified into two main categories, i.e., the grounding grid in a traction substation and the integrated grounding line along a track. The surface potentials, which resulted from the IGS, can be investigated through the electromagnetic calculation of the grounding conductors. Thus, the relationship between the surface potentials and the levels of conductor corrosion can be quantified. As a result, the breakpoint location and the levels of the conductor corrosion of the grounding conductors can be determined by the surface potentials calculated. Finally, the IGS model is simulated in the current distribution, electromagnetic fields, grounding, and soil structure (CDEGS) analysis software, and the results verify the accuracy of the proposed model.