Study on the electromagnetic interference effects of traction current on track circuit systems

LI Hailong; WEN Yinghong; XIE Bocai; REN Jie

doi:10.11860/j.issn.1673-0291.20240136

Abstract：To address the susceptibility of ground-to-train information transmission in track circuits to interference from traction currents in electrified railway traction power supply systems,this study em-ploys finite element simulation software to develop a ground-to-train information transmission model and investigates the electromagnetic field characteristics of the information transfer process between the track circuit and the Track Circuit Reader(TCR)antenna.First,a simulation model of ground-to-train information transmission is established based on the operational principles and installation configu-ration of the track circuit system.Second,the model's validity is confirmed by using track circuit sig-nals as the excitation source and comparing key parameters of the TCR antenna's induced voltage,in-cluding peak value,carrier frequency,and low-frequency modulation.Finally,measured traction cur-rents are applied as excitation sources to analyze the electromagnetic interference effects on ground-to-train transmission under both balanced and unbalanced traction current conditions.Simulation results indicate that with measured data as the excitation source,when traction current in the rails is balanced,the peak induced voltage at the TCR antenna is approximately 1 mV,and traction harmonic currents cause no interference to the track circuit system.However,when the peak value of the unbalanced cur-rent in the rails reaches 1.1 A,the maximum peak induced voltage of the TCR antenna reaches 220 mV,generating interference signals within the operating frequency band of the track circuit.These findings provide valuable theoretical guidance and practical reference for electromagnetic com-patibility design of electrified railway signaling systems and for enhancing the anti-interference perfor-mance of TCR equipment.