Research On The Coordination Of Metro Vehicle And Traction Network Protection For DC Traction Power Supply System

In recent years,the construction of metro traffic is developing rapidly with the continuous expansion of the Chinese city scale.Meanwhile,more and more attention is paid to the safety of metro traffic.The consequences of short circuit fault in metro system are serious,which may cause equipment damage and even endanger the safety of passengers.Metro transportation system can ensure the rapid and reliable removal of short circuit fault occurring on.DC traction power supply system through vehicle and traction network protection(feeder line protection)configuration.Therefore,it is of great significance to study the coordination of the vehicle and feeder line protection.In this dissertation,a series of studies have been carried out around above contents.First,the working principles of metro power supply system and metro vehicle were studied systematically.Based on MATLAB/Simulink,a complete simulation model of power supply system was formed.The simulation model consists of AC power supply system module,DC traction power supply system module,metro vehicle module,etc.The correctness of the rectifier unit model was test and verified.And the actual data of phase 1 project of Chongqing metro line 10 was used in the simulation model.After that,the protection configuration of DC traction power supply system was analyzed comprehensively.The action characteristics of feeder line protection including large current tripping protection,DDL protection,definite time overcurrent protection,low voltage protection,thermal protection,two way inter-tripping protection were analyzed in this dissertation.And the action characteristics of metro vehicle protection including high speed circuit breaker protection and main fuse protection were subsequently discussed.Supported by the research of feeder line protection and vehicle protection,the coordination principle of protection configuration was put forward.On the premise of establishing the simulation model and defining the principle of protection coordination,various short circuit faults occurring on the catenary and the metro vehicle were simulated.Combined with the scheme of vehicle and feeder line protection configuration,the data of simulation results was analyzed.The coverage map of vehicle protection and the action time of vehicle and feeder line protection were then obtained.Sequence diagram of the protection configuration verifies the rationality of the actual scheme for phase 1 project of Chongqing metro line 10.And the method for protection coordination was also sorted out.At the same time,field measurements were carried out,and the test data of short circuit current and statistics of protection action for DC traction power supply system were obtained.The validity of the simulation model and the reliability of feeder line protection action were verified.Finally,based on the platform of MATLAB/GUI,the software was developed to analyze the coordination of vehicle and traction network protection.The functions of steady short circuit current calculation,transient current simulation,protection coordination analysis can be carried out conveniently with visual operation interface.And the report of protection analysis can be output,which provides the guidance on protection configuration for DC traction power supply system.