Research Of High-speed Maglev Train-track Rigid-flexible Coupling System Based On Cross And Vertical Sections Conditions Of The Line

With the development of science and technology in rail transportation,the high-speed three-dimensional transportation network is improving constantly.Developing the high-speed maglev technology has become a major trend in the future of rail transportation,which has been listed as one of the important technical reserves of strategy of building China into a country with strong transportation network.This thesis aims at the high-speed maglev train-track system.Based on the of multi-body dynamics and rigid-flexible coupling dynamic theories,the vehicle-track coupling relations as well as the modeling methods of maglev frame,control system,magnet-track interaction are investigated.The modeling of cross and vertical sections of maglev line are also studied.The magnet-track dynamic interaction and train running quality are analyzed when the maglev train passes through the different cross and vertical sections of the line at high speed of 200～600km/h.The rigid-flexible coupling dynamic model of maglev vehicle with flexible bogie frame was established.The dynamic performance differences between single vehicle and train were discussed.The flexibility of substructure on the system dynamic behavior was analyzed.Moreover,the train-track dynamic model with flexible guideway girder was established.Based on this,the force conditions,vibration and deformation characteristics of guideway girder locating in the different cross and vertical sections were researched.Its influence on the dynamic performance of maglev vehicle and levitation system was also analyzed.Excited by the track random irregularity,the dynamic response characteristics of train-track coupling system was investigated deeply.The results show that,in the train model,the dynamic interaction between the connected vehicles mainly affected the vehicle levitation performance.On straight line,the maximums of levitation force and gap calculated by the train model can increase by 13%and 3.4%respectively,comparing with that of the single-vehicle model.In curves,the levitation force and car body vertical acceleration obtained from the train mode have the increments of about 11.6%and 11%respectively with respect to that of the single-vehicle model.At different operating speeds,the vertical section conditions had more significant influence on the train’s running performance than the cross section of line.Relative to the line vertical section,the influence of the flexibility effects of maglev frame and guideway girder on the train lateral dynamic performance relatively greater.The overall differences of dynamic index amplitudes were 5%～35%.Especially for the guiding force and the lateral acceleration of carbody,the differences can reach about 2.5 k N and 0.22 m/s~2.In addition,the maglev frame flexibility had little effect on the dynamic characteristics of track vibration,whilst the speed rise may increase in the dynamic response of flexible track.The dynamic response of the simply supported beam was higher than that of the continuous beam,The mid-span vertical displacement and acceleration of the former increased by 4.89 mm and 2.24 m/s~2 relative to the latter.The marshalling mode of maglev train should be considered in the modeling.The analysis error caused by the elastic vibration of the maglev frame and the flexible track as well as its coupled vibration is generally less than 35%.Rigid model can still reflect the actual operating state of trains in line operation to a certain extent,and the modeling method based on rigid-flexible coupling dynamics can ensure higher calculation accuracy.