Heterogeneous Safety Computer And Its Application Research In Maglev Vehicle Operation Control System

The maglev train operation control system can be divided into three parts: centralized control system,decentralized control system and vehicle control system.Among them,the vehicle operation control system is a safety-critical system,which mainly realizes the speed curve monitoring and train protection of the maglev train,and the importance of the safety computer as its core component is self-evident.The safety computers currently in use are basically homogeneous structures,the safety and reliability of certain common-mode failures needs to be improved,this thesis studies the differential 2oo3 safety computer technology and successfully applies it to the maglev vehicle operation control system,it has important theoretical significance and reference value for solving such problems.First of all,this thesis analyzes the functional requirements and completes the overall architecture design of the maglev vehicle operation control system,on this basis,the safety of the system is analyzed,and the safety constraint that the reliability of the safety computer has an important impact on the entire system is given.Secondly,a heterogeneous 2oo3 safety computer with higher fault tolerance in the face of common-mode failure is designed,and the system reliability is analyzed,and a conclusion is obtained that the effect is better than that of the homogeneous 2oo3 safety computer.Finally,a maglev vehicle operation control system with a heterogeneous safety computer as the core is built and related tests are conducted,and satisfactory results are achieved.The main work of this thesis is as follows:(1)The functional requirements analysis and overall architecture design of the maglev train's vehicle operation control system are performed,and the system safety analysis is performed using the STAMP model and the STPA method to obtain the reliability of the safety computer.The safety constraint rules that the reliability of the safety computer has an important influence on the entire system are obtained.(2)Based on the safety constraint rules of the vehicle operation control system of the maglev train,a heterogeneous 2oo3 safety computer is designed,which is mainly aimed at the main control board hardware architecture and the operating system running on it.At the hardware level,the three series of main control boards use Coldfire,ARM,and Power PC three different architectures;at the operating system level,the three series of main control boards run Vx Works 6.6,Vx Works 7.0,and QNX 6.3 three different operating systems.(3)Using the method of fault tree,the differential 2oo3 safety computer designed in this thesis is modeled and its availability is analyzed,and it is concluded that the maintenance rate can improve the system availability within a certain range.At the same time,comparing the reliability of the heterogeneous and isomorphic 2oo3 safety computer,the conclusion is drawn that the former has higher reliability without maintenance.(4)This thesis completes the development of the heterogeneous 2oo3 safety computer prototype,and builds a maglev vehicle operation control system with the heterogeneous 2oo3 safety computer as the core.Then,the system is tested on site such as door protection,vehicle suspension and landing,communication test with OBC,braking test,normal driving,traction cutoff and emergency braking accuracy,train operation protection,etc.,which proves that the system can work normally jobs.This thesis contains 68 figures,6 tables and 55 references.