Model of the Influence of Interference of a 25 kV 50 Hz Traction Network on Parallel 50 Hz Track Circuits

The problem considered in the work is related to ensuring the electromagnetic compatibility of track circuits with a parallel traction network. To evaluate the influence of interference from the alternating current traction network on the operation of the track circuits a simplified model has been developed. The model is based on the well-known multiconductor transmission line method, however, its use for modeling a traction network is difficult due to the longitudinal structural inhomogeneity of the traction system. The simplification proposed in the work assumes that the track circuit equipment connected to the rails insignificantly influence on the distribution of currents in traction network conductors. These assumptions make it possible to neglect the equipment of track circuits at the first stage of modeling, which greatly simplifies the equivalent circuit of the traction network, and allows us to represent it in the form of several homogeneous sections of multiconductor transmission lines with rolling stock units between them. Simulation of induced alternating current interference in the rails of the track with direct current traction is carried out at the second stage, taking into account the design features and electrical parameters of track circuits, as well as specific values of rail-to-ground conductance and earth conductivity, using the values of the currents in the traction network conductors determined in the first stage.