Transient Response Analysis Of ZPW-2000A Track Circuit Considering The Influence Of Line Coupling

Abstract

In order to solve the problem that the transient response of ZPW-2000A track circuit cannot be calculated directly in time domain, the modified nodal admittance method (MNA) combined with Q-D method is proposed to analyze the transient response of ZPW-2000A track circuit. Firstly, the hybrid model of traction network lines and ZPW-2000A track circuit is established. Secondly, using this model and Kirchhoff’s law, the MNA time domain equation is obtained. Through Laplace transform and decoupling, the complex frequency domain solution of the rail surface voltage at the receiving end of ZPW-2000A track circuit is obtained. Then, the numerical time domain solution of rail surface voltage is obtained by using Fourier transform and Q-D algorithm, and a simulation model is built to verify the correctness of the proposed method. Furthermore, the variation laws of the rail surface voltage at the receiving end affected by frequency, transmission distance and ballast resistance are analyzed. Finally, when the train enters and leaves the track section, there is a transient process, which can provide a reference for the train occupancy inspection and when the air core coil is in fault state, its transient response is different from that in normal state, which provides a reference for fault detection of track circuit.

Keywords

• track circuit
• multi-conductor transmission line
• transient response
• modified nodal admittance equation
• q-d algorithm