Analysis Of Rail Potential And Surface Potential Of Integrated Grounding System In Different Sections Of High Speed Railway

The traction load of high-speed railway is greatly improved.It is much bigger than express railway.This cause a high rail potential which threaten the safety of equipment along the railway line.In severe time even threaten the personal safety of staff and passenger.So some necessary measures are needed to reduce the rail potential.There are three different sections during the construction of high speed railway.The traction network models of subgrade,viaduct and tunnel are different.It is necessary to'study the distribution of rail potential in different sections and take corresponding measures to reduce the rail potential.Integrated grounding system is the most important part among the various measures to reduce the rail potential.But in the actual,integrated grounding system often defects.So it is necessary to study on the detection method of integrated grounding system defects in different sections.First of all,this paper which based om multi conductor transmission line theory infer the chain network model of high speed railway traction network.Then it use the theory of Carson,Mirror method and infinite circle model to figure the conductor electrical parameters of subgrade section,viaduct section and tunnel section out.To lay the foundation for follow-up study.Then,this paper use Matlab/Simulink simulation software to build the full parallel AT power supply system model.Pointing at rail potential to make a simulation analysis.THE results show that the rail potential is inhibited when the line is added CB line,CPW line and ad hoc ground.But this methods do not meet the standard requirements.And then we add the through ground wire.The above three sections in each AT segment set up 3,7 CB lines and CPW lines.The amplitude of rail potential is up to the standard.The importance of setting up the integrated grounding system is verifiedThe distribution of ground surface potential is analyzed when the ground wire is in defect.CDEGS simulation software is used to build the simulation model of the three grounding system.The simulation analysis of ground surface potential over the ground wire is carried out.The simulation results show that surface potential is smooth curve without catastrophe point when the integrated ground is health.There are three peaks in the locomotive,the beginning and the end of the line.The surface potential break at the location of ground fault when the integrated ground defect.The range of the mutation on the surface potential is the range of the defect range of the integrated ground.The above method is also feasible when the defects of the integrated earth wire occurred in different sections.The surface potential of the integrated grounding system is the highest on viaduct section and the lowest on tunnel section.Thus a method to detect the defects of integrated earth wire by the distribution of surface potential is presented in this paper.The feasibility and effectiveness of using this method to detect the defects in different sections are verified...