Interference Analysis And Research Of ZPW-2000A Jointless Track Circuit Between The Parallel Lines

With the rapid development of Chinese railway, train operation speed is continuouslyaccelerated step by step. At the same time, it puts forward higher requirements for thereliability of the signal system. ZPW-2000A track circuit is regarded as an importantfoundation signaling equipment of high-speed railway, its reliability is directly related tosecurity of train. In electrified railway complex electromagnetic environment, the track circuitelectromagnetic interference is also increasing, especially in some busy trunk lines, due to theincrease of the parallel line, the track circuit transmission signal interference between adjacentlines is of frequent occurence, sometimes even cause phenomenon of the section signalupgrading show, especially in the four parallel lines, otherwise, the circuit uses the samecarrier frequency may cause the track circuit and locomotives and can not correctly identifythe section or interfering signals, which cause the potential accidents. Therefore, it isnecessary to analyze track circuits frequency interference on adjacent lines. Protectivemeasures are also proposed.Capacitive coupling, ballast resistor leak conductive coupling and inductive coupling hasbeen observed to be the basic influencing factors that interference ZPW-2000A non-insulatedtrack circuit, among them, the ballast resistor leak conductive coupling and inductive couplingis the main coupling form with frequency interference between track circuit. The maincontents are as follows:(1) The thesis illustrates the ZPW-2000A track circuit components and working principle,analyzes three kinds of interference coupling of ZPW-2000A, and introduces the workingprinciple of track circuit information receiving unit.(2) The four-terminal network model of track circuit and its tuning unit are discussed, theco-channel interference coupling model based on ballast resistor leak conductive coupling andinductive coupling is established, the parameters in the model are calculated, a line trackcircuit interference is simulated and compared with the test data to verify the correctness ofthe model.(3) Making a scrutiny into double block non-ballasted track parallel line ZPW-2000Atrack circuit interference, the process of simulation is discussed in detail. Simulationparameters include carrier frequency, parallel length of the track circuit, compensationcapacitor spacing, ballast resistor and line spacing. The results show that the higher the carrierfrequency, the longer the track circuit parallel length, the larger the ballast resistor and thegreater the interference, when interval of the main and complement string loop compensationcapacitor is equal, the interference is also increased, the lines intermission are increase, theinterference is reduced. Finally, the thesis presents a method to improve the interference of the track circuit of ZPW-2000A.