Analysis And Design Of The Signal System Of The South Extension Line Of Chengdu Metro Line 1

Chengdu has been designated as a key node city in "Chengdu-Chongqing Urban Agglomeration Development Plan" by the state.In the future,its city size and population will increase substantially.To solve the problem of traffic congestion caused by population growth,it is a promising solution to speed up the construction of metros.However,as the "brain" of metro operation--the core technology of signal system has always been mastered by foreign manufacturers.Accordingly,concerns like high construction cost,high maintenance cost and huge difficulty in interconnection seriously restricts the development of China’s subway industry.This thesis takes the actual project of the south extension of Chengdu Metro Line 1 as the Case Study.Firstly,according to the functional requirements,operation organization,control methods of the south extension of Chengdu metro line 1,a performance comparison between the automatic train control(CBTC)system based on the communication technology and the point train automatic control system is made in terms of system function,operation,technical maturity and the whole life cycle cost.With this,an optimal design method based on the CBTC is obtained applied in metro signal system.Secondly,the details of the four sub-systems of the CBTC system applied in signal system,e.g.,automatic train protection,computer interlocking,automatic train operation and train automatic monitoring,are provided.More specifically,the contents including the train speed and distance measurement,the train positioning,the safety braking,the train running control,the station stopping precision control and the speed adjustment control are elaborated.Then,the composition and working principle of three auxiliary systems(e.g.,data communication subsystem,signal centralized monitoring subsystem,power supply subsystem),which are used to ensure the reliable operation of the signal system,are also introduced in this paper.Finally,by using the ATO-Grapha software,the mode tests are carried out on the running interval and running time of the CBTC system in the upstream and downstream directions of the main line.To further improve the transport capacity of the metro,during the initial operation period,the actual tests are conducted on the on-site train running data,and the test data are analyzed and calculated to verify the effectiveness of the proposed design method for metro signal system.Taking the south extension of Chengdu metro line 1 as an example,a design method for metro signal system is proposed in this thesis.In this method,it can achieve the flexible construction cost and optimal maintenance cost.Under the condition of the accelerated network construction of Chengdu rail transit,the proposed design method can provide a reference for the functional design and construction management of the metro signal system of subsequent lines,and promote the early realization of accelerating the network construction of Chengdu rail transit.