Track Occupancy Detection Using Ratio of Open-Circuit Impedance to Short-Circuit Impedance

Anotace: This paper deals with the change of the ratio of the open circuit impedance to short-circuit impedance of the electric traction depending on the distance of the traction vehicle from the beginning of the section. This ratio is calculated in order to estimate the traction vehicle speed and the distance at which the track occupancy can be indicated. Therefore, the impedance moduli and the impedance phases of the open track circuit and the impedance of the occupied track (short-circuit impedance) is compared at different short-circuit distances. The impedances ratio varies with changing weather conditions. It is different in dry weather than in the rain. Therefore, in practical use, the track occupancy indicator must always be updated and the ratio must always be recalculated for the new situation. In this paper, the impedances ratio is calculated for specific parameters measured in the section of the track in Orlova. The distance between a reference point (place of short circuit rails) from a measuring point is for the impedance module ratio of F = 10 about 218 m.