Research On Protection Ability Of ZPW-2000A Track Circuit On Tuning Area Faults

ZPW-2000 A track circuit is an important component part of Chinese Train Control System and plays a role in protecting the safety of trains.Its equipment faults have a great impact on the normal operation of the track circuit.Tuning area fault is one of the common faults of ZPW-2000 A track circuit and the current researches on tuning area faults mostly focus on fault diagnosis or fault treatment according to maintenance workers’ experience.They mostly belong to the researches on maintainability,but there is no analysis on protection ability of track circuit against tuning area faults in the respect of safety.Therefore,it is necessary to establish transmission models of track circuit with tuning area faults.And the protection ability of ZPW-2000 A track circuit against tuning area faults is further qualitatively and quantitatively studied.This thesis establishes single-element-fault models in different operating states and double-elements-fault models in different fault locations by transmission-line theory.By analyzing the influence of tuning area faults on transmission characteristic of track sections and adjacent track sections,the fault protection ability of the track circuit is studied.Aimed at the shortcomings of current protection ability,it is verified that the compensation tuning unit protection can improve the protection ability of the ZPW-2000 A track circuit.The specific research contents are as follows:(1)To establish the basic signal transmission models of different components of ZPW-2000 A track circuit according to the structure of equipment components by the transmission-line theory.And then derive the tuning area fault models in different operating states based on the models of components: tuning area fault model in normal state,tuning area fault model in shunting state,tuning area fault model in broken state,tuning area fault model in locomotive signal state.(2)To propose the most unfavorable rail voltage or shunting current to measure the protection ability of track circuit against tuning area faults based on the models.And analyze the protection ability of ZPW-2000 A track circuit on the tuning area single-element faults.On the basis,the protection ability of tuning area double-elements faults of the track circuit is also studied:(1)the protection ability of double-elements faults in the same tuning area is also studied.(2)the protection ability of double-elements faults in different tuning areas is analyzed.The results prove that the track circuit has a great protection ability on the tuning area faults.(3)To establish the models of the compensation tuning units with the design method of the UM2000 track circuit.And prove that compensation tuning units can improve tuning ability with track circuit normal operating and effectively protect signal over-zone transmit,which is applied to ZPW-2000 A track circuit and improves the track circuit protection ability against tuning area faults.