Research And Application On The Key Techniques In The Railway Signaling System

The scale of the city is getting bigger and bigger,its modernization is getting higher and higher,but the traffic congestion is becoming more and more serious.At this time,urban rail transit has become the first choice for many cities at home and abroad to solve traffic congestion because of its fastness,safety,punctuality and energy-saving.The communication-based train control(CBTC)system is widely used inevitably for its advanced technology in railway transportation projects.Due to the specificity of its operating environment and the function,CBTC system is decided to be a large and complex safety-critical system.In order to provide hardware and software support platform for the operation of the train,CBTC system must rely on the mutual cooperation of the various subsystems.During the process of development and implementation,many vital technologies play a vital role to ensure the safety,efficiency,comfortablity,punctual,energy-saving of the train operation.Therefore,this thesis focuses on some vital technologies for CBTC system to achieve the goals of improvement of system safety and reliability,enhancement of system performance and reduction of energy consumption in the process of train operation.The main contents of research area are as the follows.Firstly,a compact fail-safe computer platform is proposed and implemented.Contrast to the common platform architecture,it streamlines the platform architecture,optimizes the communication links and its configuration is flexible.In addition,we give a detailed description on the achieved vital technologies,such as synchronization and vote,secure communication,conditional power and requirements modeling,which enhance the performance of the platform with ensuring the reliability and safety.Secondly,two kinds of safety output hardware 2 out of 3 voters are designed and implemented,dynamic voter and static voter.And models are built up to analyze their reliability and safety via Markov Chain theory.The two markov models show that the voters both have have a high reliability and safety,and their MTTF and THR can meet the SIL4 requirements of EN50129.At last,we recommend the matching voter according to the different application scenarios.Thirdly,in the case of some unknown speed limit information,a double-layer ATO energy-saving control algorithm based on genetic algorithm for single-track multi-train is proposed.The search layer searches for the best coast and acceleration position to save energy;the protection layer protects the train under the speed of the ATP limit and avoids the emergency brake to be released.In addition,this paper also studies the multi-particle train model based on genetic algorithm,it can ensure the accuracy of that algorithm.Finally,the classification of failure and emergencies outside the CBTC system are studied.In order to make the CBTC system better respond to these failure and emergencies,this paper puts forward the global safety principle.And then the behaviour states of the train,ZC protection unit and holonic fault monitoring system are modelled via CPN theory.The state space analysis and the ASK-CTL model checking are also used to verify the correctness and safety of the CPN model.