Mathematical Model of the Induced AC Interference in DC Rails of a Double-Track System

The article considers a simplified model for evaluating interference in rails induced by a nearby alternating current traction network. The advantage of the proposed simplified model is that the model does not require accurate accounting of the parameters of all track circuits along the entire length of the feeder zone, which greatly simplifies and speeds up the application of the model. The possibility of using such simplification is based on the fact that the track circuits equipment affects the redistribution of the traction return current in two rails, mainly in the local area where this equipment is installed, and this redistribution insignificantly affects the currents in other conductors of traction network, since the distance from rails to other conductors is much greater than the distance between two rails. This assumption allows at the first stage of modeling to determine the distribution of alternating traction current in the conductors of the traction network without taking into account the track circuits equipment. At the second stage of modeling, the equipment of track circuits is taken into account only for the track section for which it is necessary to determine the level of induced interference and evaluate its impact on the operation of track circuits