The Safetyassessment Of High-speed Signal System Based On The Model

High-speed rail signaling system includes train control systems,computer interlocking system,dispatcher centralization,signal monitoring system etc.Its complex structure,a combination of a large number of computer network technology,large-scale use of modern control technology,highly redundant,highly secure reliability,has played an irreplaceable role for high-speed railway safety and efficient operation.However,during the high-speed railway in operation,some defectives occur frequently,which planted a huge risk of the safe operation of high-speed railway.Once a small probability of defective events do not get effective control,which will lead to a major accident,and the result is disastrous.Therefore,it is a very important significance thatanalyses the safety,reliability of high-speed rail signaling system,identify security risks of their systems,reduce safety hazards and ensure the safe operation of high-speed rail.By analyzing the functions and structure of the high-speed railway signaling system,using the formal modeling tool Simfia to establish safety analysis model for high-speed railway signaling system,and using FTA method and the method of FMECA to analyse qualitatively and quantitatively factors that could cause the high-speed railway signal system failure,we can obtain the failure probability and minimal cut sets of the failure top event.With the analysis of results to ascertain the systemfailure modes and causes may occur and take measures to improve,it can enhance system security.The main contents of this paper are as following:Firstly,it analyzes the risk assessment status of domesti and international high-speed rail,compares the advantages and disadvantages of several common safety analysis methods,and noted that the widespread use of PHA,FFA,HAZOP are highly subjective,which have deficiencies in the high-speed rail safety assessment.To this end we proposes to use Simfia tool for high-speed rail system modeling analysis.Secondly,according to study the high-speed rail safety standard signaling system,security model,security analysis,risk factors,and the level of risk management division,and analyze the RBC system,interlocking system,centralized dispatching and on-board equipment four functions module,we establish of Simfia model respectively.Thirdly,based on the use of Simfia powerful data logic processing capabilities for fault tree analysis of the mode,we use FMECA method to identify the failure modes and weaknesses of the model,and propose imrovement program.After improving model,the simulating again,the results show that the improved onecompliance with the relevant safety standards,and Simfia is able to provide efficient and accurate safety assessment of high-speed rail system.Fourthly,the safety assessment for ahigh-speed signal system.The high speed rail is the main high-speed rail line in central China,its safe operation to protect the national strategy of "silk road" economic belt of the rapid advance plays an important role.Through the simplification of high speed railway signal system,Simfia model is set up,test model results.Results show that followed the iron safe and reliable,at the same time to identify the weak links of the system,has important reference value for the daily maintenance and inspection of the high speed rail.