Research On Application Of Function Safety Analysis Of Train Control Center

Function safety analysis is a kind of system analysis technology in the design stage of the system safety life cycle, which can help to ensure the proper execution of the system's related function and control the risk that exist in the system effectively.Function safety analysis, predicts the unsafe factors of the system by hazard identification and preliminary risk analysis. Then safety analysis ensures the safety of the system to meet the requirement of Safety Integrity Level through some methods that can reduce the risk, such as options analysis of risk control measures and analysis of the effect of options.This thesis studies the application of functional safety analysis techniques through analyzing the safety of two functions of TCC (Train Control Center) based on the railway signaling safety-related standards and specifications and the theory of the reliability and safety.First, the function and the requirements of the function are defined as following: Temporary Speed Restriction, Interval Signal Control based on Technical Specification for Train Control Center of CTCS-2 Train Control System for Dedicated Passenger Lines. the methord of FMEA and brain-storm is used to identify the hazard of the sub-function and the interface in order to get the failure modes of the main functions.Second, FTA is used to build the fault tree of the failure modes of the main functions and to seek the causes of the failure and to calculate the frequency of the failure modes, and analyze the failure of the system function qualitatively and quantitatively.Make sure the level of the severity of the failure modes of the main functions, and accomplish preliminary risk analysis according to Risk matrix.Third, the improved measures for the design are found based on the failure modes and the requirements of the safety function are defined. FTA and ETA are applied to execute the cause and consequence analysis of the safety function, then make sure the frequency of the accident and the level of the severity after risk reducing, accomplish the analysis of effect of options according to Risk matrix. And the two main functions of TCC meet the requirements of the Safety Integrity Level are verified.At last, the content of this thesis is summarized. The problems which still exist and the future work to do are also mentioned.