Probability Distribution Modeling of the Interference of the Traction Current in Track Circuits

As a main interference to track circuit signal, the interference of the traction current(ITC) will directly influence the transmission quality of track circuit signal and even lead to signal distortion which would endanger the traffic safety. The ITC has a complicated formation mechanism and it is affected by factors of train compositions, load and running speed, so it is hardly possible to establish accurate mathematical analytic model of ITC. This paper has analyzed the probability distribution characteristics of the ITC extracted from real train operating data collected by the cab signal system. A method using Kolmogorov– Smirnov (K-S) test and least square approximation has been proposed to establish the probability distribution model of the ITC. Feasibility and applicability have been confirmed by examples. The probability distribution model of the ITC has a significant importance for analyzing track circuit signals especially for interference signal simulation.