Research On The Safety Of Double Two Out Of Two Computing Platform Based On EN50129

As the rapid development of railway in China, passenger dedicated line and high-speed railway is establishing, which largely increase railway signal transmission and make high reliability and safety requirement for computer interlocking system. To ensure the reliability and safety of computation, applying double two out of two Safety Computing Platform instead of single CPU in signal device of railway system can reduce safety risks like external influence, operating system or compile components error. At the same time, European signal standard EN5012X is gradually accepted by China. Under the guidance of the standard, developing computer interlocking products that in the line with its safety level is a effective way to improve the reliability and safety of the computer interlocking system.This article discuss the reliability and safety analysis method for double two out of two safety computing platform and safety assurance measures. On the one hand, in the basis of research for double two out of two safety computing platform, author makes platform structure model and proves its reliability. On the other hand, author studies the European railway standard thoroughly, refers to its specification and requirement, then brings safety integrity into the fault analysis and safety design. After analyzing potential risks in the process of system operation, the various factors that cause system faults are identified via Fault Tree method, assessed and quantified.To reach system safety target, author researches safety strategies for reduce the probability of risks, control the faults in the way of technology and management and attempts to prove the feasibility of those strategies by theoretical calculation and simulation experiment. It make the conclusion that the application of the safety measures can largely reduce the probability of risks, reach the safety level requirements specified in the standard and assure system safety.