MATHEMATICAL MODELING OF THE OPERATION OF AUDIO FREQUENCY (NO JUNCTION) AND JUNCTION RAIL CIRCUITS

Rail circuits are the basic elements of modern railway automation and telemechanics systems, performing the functions of track sensors and telemechanical channels. It is shown that the calculation of their operating boundary conditions becomes more complicated with the application of junctionless audio frequency rail circuits. The analysis of track circuits consists of studying the changes in their operation in various modes when the circuit parameters are changed. During the analysis, the optimal values of the parameters of the circuit elements and the frequency of the power source are determined for the given operating conditions. An analysis of the factors affecting the operating currents and voltages of such rail circuit schemes has been carried out. When analyzing and calculating a track circuit, it is assumed that the track line and equipment elements are linear, that is, their parameters do not depend on the flowing currents. To simplify the calculations, the track circuit is represented by the corresponding mathematical model (equivalent circuit) for each mode. Depending on the type of equivalent circuit used, four-pole and multi-pole models are distinguished. At the same time, the analysis and reporting of jointed rail circuits are carried out. Based on their results, the directions that allow for more accurate modeling of the operating modes of the circuits of the non-joint audio frequency rail circuits have been determined. Keywords: Rail circuits, train traffic safety, audio frequency (no junction) track circuits, junction rail circuits, signaling system, track sensors, mathematical model, remote conditioning monitoring.