The Risk Assessment Of Axle Crack Based On The Var Model

Under the current situation,the population is in a sharp increase in cities in the development of the urbanization process.Thus,rail transit system will comfortably be the safest and most secure way to travel.However,axle safety is undoubtedly an important condition for high-speed EMU,railway locomotives or trucks.,which is an important part of locomotive running connecting axis of wheelset and producing great importance to train safety.Axle failure has the following forms: corrosion,material internal,defects insufficient surface processing,friction damage,external damage,etc.If you cannot find and deal with the fault status of the axle to perform risk rating,a very painful loss is likely to be resulted.Therefore,it is necessary to extract the acoustic emission signal of the axle to determine the level of risk.After we found the risk level of the fault in time,we should take the corresponding measures to deal with the accident.Refusing the occurrence and harm of accidents and ensuring the safety of passengers.Anything has the risk,the axle cracks will bring immeasurable loss in the locomotive running.so the axle risk assessment has great practical significance.Under the requirements of the task force,the task of this paper is to use the vector autoregressive model of econometrics to the analysis of the acoustic emission signal of the axle.the vector autoregressive model has long been used for the analysis of the relationship between the various variables in econometrics,the establishment of the vector autoregressive model requires a stable data,its own needs to significance of parameters,model's stability and hysteresis order,etc.In the paper,the vector autoregressive model is established in two ways,the impulse response function of the acoustic emission signal is obtained,and the reference signal is set up..And the new random acoustic signal are input to the mode in two way,contrast the new impulse response function with reference signal group's,then the running state information of the axle risk grade that the sound signal represents is judged.On this basis,a simple risk assessment table is established,achieving the acoustic emission signal risk assessment of axle crack based on the vector autoregressive model.