TSSM Based Modeling And Verification Of VBTC MA Unit In VOBC

With the development of communication and control technology,there has emerged the next generation of train operation control system based on vehicle to vehicle communication.This system breaks the traditional train control theory centrally controlled by zone controller,and establishes a system model using autonomous control of trains as the core.The on-board device autonomously calculates Movement Authority(MA),according to line resources states and train running status,to achieve the intelligence of on-board system.However,the Vehicle-to-vehicle Communication Based Train Control system(VBTC)is still at the exploratory research stage at present.Especially,the study of MA under VBTC structure is also inadequate and the system demands higher efficiency and flexibility.Therefore,the study on MA algorithm and functional realization has both theoretical meaning and application value.In this dissertation,we analysis the function requirements of MA and propose a proper MA algorithm for VBTC based on the architecture and data flow of VBTC.The proposed method guarantees the train running safety,enhances the flexibility and efficiency of train operation,and shortens train tracking interval.In order to verify the correctness and effectiveness,the MA algorithm is analyzed and modeled by using the Timed Safe State Machine theory(TSSM),and simulated&verified by UPPAAL.Simultaneously,we use the Matlab to simulate the tracking scene.The result shows that the proposed algorithm is effective.The main contents are described as follows:(1)We introduce the basic principle of the VBTC system and moving block,and analyze the characteristics,function requirements and algorithm principle of the MA in VBTC from the function and interface of the vehicle.In addition,the feasibility of moving block scheme based on relative velocity is analyzed and demonstrated.We also propose a strategy to achieve tracking interval optimization.(2)According to the requirements of MA and the train running scene,the dissertation analyzes and designs the MA algorithm,including MA calculation under single running,MA calculation under multi-vehicle tracking,MA calculation under multi-vehicle subtending,MA calculation under the temporary speed information included.(3)In terms of the function requirements,the MA can be divided into five modules:Train Sieving Module,Train Safe Position module,Extend TrainPath Module,Update PathMessage Module and Calculate MA Module.The modules are modeled and analyzed by using the hierarchy,concurrency,preemption and time property of TSSM.(4)To verify the correctness of the MA algorithm,the MA model is simulated by UPPAAL.To verify the validity of tracking interval optimization,the moving block scheme based on relative velocity is simulated by Matlab.The main innovation of this dissertation is proposing a MA algorithm,a module design scheme and the moving block scheme based on relative velocity in VBTC system,and using the theory of TSSM to verify the MA module model.These provide theoretical basis for system design and provide reference for subsequent research on VBTC system.