Research On Electromagnetic Interference Of Jointless Track Circuit

The high-speed railway of China is widely distributed,and the electromagnetic environment it faces is very complicated.With the continuous improvement of the speed,the integration of CTCS electronic devices is getting higher.Meanwhile,its electromagnetic susceptibility is getting higher.As an essential subsystem of CTCS,if the track circuit system is subjected to electromagnetic interference(EMI),it will affect the safety and efficiency of the vehicle.Therefore,the importance of studying the effects of EMI on track circuit is self-evident.This paper takes the ZPW-2000 A jointless track circuit widely used in high-speed railway as the research object,it analyzes the EMI which include the adjacent line crosstalk caused by signal transmission and external electromagnetic pulse.The main contents are as follows:(1)The adjacent line crosstalk is analyzed using the 3D full-wave electromagnetic simulation method,because it becomes more serious in tunnel than subgrade.The double-line ballast track models are modeled for subgrade and tunnel,and it's verified to be correct by comparing the primary parameter simulation results with the standard.The influence of different factors on the adjacent line coupling voltage is simulated.The multiple relationship of adjacent-line mutual impedance coefficients under two conditions is studied,which makes up for the shortcoming of the existing method and provides a new idea for calculation and predictive evaluation for the adjacent line crosstalk research.(2)The research on electromagnetic pulse(EMP)coupling effect of high-speed railway track circuit system is still in the early stage.The simulation of EMP irradiation and the pulse current injection(PCI)test of track circuit are carried out for the first time according to relevant standards in this paper.The distribution law of rail coupling current and rail surface electromagnetic field under different incident angles of EMP is simulated.The transient electromagnetic interference caused by electromagnetic pulse coupling effect is preliminarily studied.It provides a reference for track circuit system to protect against the fast rise-time electromagnetic pulse.(3)Aiming at the problem that the surge protection device(SPD)of track circuit system can't protect the high frequency exponent of the fast rise-time electromagnetic pulse,the pulse current injection(PCI)to SPD is carried out according to relevant standards.The research results show that SPD of the track circuit is not fast enough to effectively protect the peak value of transient electromagnetic pulse.It's provides a reference for the electromagnetic interference protection of lightning protection system.