The Calculation And Optimization Of Train Tracking And Turn-back Based On CBTC

Train control system supervises,controls and adjusts the train speed and braking mode,which plays a vital role in the rail transit system.CBTC(Communication Based Train Control)system has been widely used and practiced in the urban rail transit system with its characteristics of systematization,networking,informatization and intellectualization.Based on the safe braking model of CBTC system and the traction calculation of trains,this paper establishes a train tracking and turn-back simulation system to solve practical problems in engineering.The safe braking model guarantees the safety operation of moving block mode,and it is the criterion that the train must follow.The traction calculation of trains analyses the force situation in the process of train operation,and establishes the relationship among train operation distance,time,speed and acceleration,which is the basis of and key to train operation simulation.The determination of the safe protection distance is an inevitable problem in the urban rail transit route planning.It is closely related to the previous civil construction investment and the later driving safety,but there is no clear indicator for determining the safety protection distance.This paper proposes a scheme for calculating the safety protection distance,explains its rationality,and obtains a calculated value through the actual line condition,which provides a reference for the design of urban rail transit lines.In order to realize convenient operation and dispatch,many stations of urban rail transit are set up as turn-back stations,which can change the running direction of the train on the one hand,and reserve the track for the temporary parking of faulty vehicles on the other hand.The type of turn-back station is also diverse depending on the difference in design requirements and actual line conditions.The ability of the train to turn back at the turn-back station becomes a key factor limiting the ability of the line carrying capacity.Based on the analysis of the turn-back capacity,this paper proposes a method to represent the structure of the turn-back station and calculate the turn-back capacity.Using this method,the turn-back capacity of the actual turn-back station was calculated.For the main functions of train traction calculation and turn-back capacity calculation,this paper proposes a design scheme to realize this function,namely the train tracking and turn-back simulation system.Using the data obtained by the system,the indicators of the evaluation circuit design are calculated to serve as a reference for line optimization.