Analysis Of Reliability And Safety For Train Control Center Based On Dynamic Fault Tree

With the rapid development of Chinese high-speed railway construction strategy, Chinese high-speed railway enters into a rapid development era. High security, high efficiency and high comfort of high-speed railway transportation meet the needs in the development of modern society. The Train Control Center(TCC) is one of the core technological equipment to ensure the safe, reliable and efficient operation of high-speed railway, so it must meet the requirements of high reliability and safety. The TCC takes computer system as the platform and contains a large number of electronic components and complex redundant configuration. The TCC is affected by various factors during operation. So a variety of failures is inevitable, and it tends to become serious obstacles to the normal operation of high-speed trains. At last, the results always cause immeasurable influences and losses. It shows that the reliability and safety analysis for the TCC has great significance to ensure the normal operation of the high-speed railway.The structure and operating characteristics of the TCC are analysed deeply, and the failure rate of constituent units of the TCC is obtained through health management technology. Considering the failure mode feature of system behaving common cause failure, maintenance, polymorphism and other failure patterns, the reliability of the TCC is analysed through dynamic fault tree analysis and Bayesian network model. Combining with the safety and reliability index of the system, the TCC safety analysis is completed, and the influence of mean time to failure(MTTF) index on the reliability and safety of the TCC is analysed. The main research contents of the dissertation are as follows:(1) The constituent units, exchange information of communication interfaces and core function of the TCC are analysed in depth. The health condition assessment model and life prediction model of constituent units are established according to the structure, function and running characteristic of the TCC, and the health index(HI) of constituent units is calculated by the health condition assessment model. Then, the concept of health life is elicited based on the health condition level of constituent units, and it can be calculated by means of the life prediction model, thus the failure rate of constituent units is obtained.(2) The common cause failure, maintenance, polymorphism of the TCC in failure modes are taken into account. Firstly, the dynamic fault tree model of constituent units in common cause failure is established and the influence of common cause failure on the reliability for the TCC is analysed. Then, for availability of the TCC, the availability index is calculated on the basis of dynamic fault tree and Bayesian network model. Finally, the degradation scene of the TCC is acted as a special working state, and the reliability is analysed and evaluated aiming at the polymorphism of the TCC in failure modes.(3) Combining with the indices of safety and reliability, the safety of the TCC is analysed. Moreover, the relationship of the MTTF index, reliability and safety of the TCC is indicated. Finally, the health diagnostic coverage factor of constituent units is elicited from diagnostic coverage factor. The dissertation analyses how to improve the MTTF index of redundant constituent units, and the purpose is to increase the reliability and safety of the TCC.