Study On The Dynamic Characteristics Of Articulated EMU

China has accelerated for construction of main line railway and urban railway.The study on the different vehicles is also increasing.At present,China's vehicle type is relatively single,and most of the vehicles are based on the traditional bogie technology.Because of the specific structure characteristics and advantages of articulated vehicle,it is widely used in high-speed train,urban rail transit vehicles and fast freight vehicles in foreign countries,which has a wide application prospect.The study and use on the articulated vehicles started late in China,and concentrated mainly on the form of carbody articulated in the low floor city vehicles.Compared with the traditional vehicle,the advantages of articulated vehicle are as following:the interaction and turbulence with the outside world is less because of less weight;improving the riding stability of the vehicle;having a good curve-negotiation performance;easily to achieve low floor of the vehicles.This paper mainly studies the use of bogie of the articulated EMU.Firstly,the structural characteristics,advantages and development of articulated vehicles at home and abroad are introduced.Then,the 3-group form of articulated EMU simulation model is established.Then the calculation of its running stability,riding stability,horizontal and vertical curve-negotiation performance is analyzed.The results indicate that all the indexes meet the requirements of GB/T 5599-1985 and UIC 518,and the vertical riding stability of car couplers is worsen than the body ends,both have reached the excellent standard.The influence of the stiffness of articulated traction device on the dynamic performance of EMU is analyzed through the established simulation model on the basis of the original parameters.The results show that the change of the radial,axial and deflection stiffness of the articulated traction device will affect the dynamic performance of the articulated EMU and show a large variation within a certain range.The torsional stiffness has little effect on the dynamic performance.Finally,the paper analyzes the dynamic characteristics of articulated EMU under different group length.The results show that the change of the group length results in the change of the bearing form of the articulated bogie.Therefore,the critical velocity,the riding stability of couplers,the wheel-rail force,derailment coefficient,the rate of wheel load reduction,wear power of wheelsets will all change in different degrees.The change in the length of the group has little effect on the above indexes of vehicles at the ends of train.