Research On Three-dimensional Train-line Coupling Dynamic Simulation And Alignment Design Parameters Of LIM Wheel/Rail Transit System

LIM(Linear Introduction Motor)wheel/rail transit system is powered by linear introduction motors,supported and guided by traditional track.It’s advantages include flexible route selection,economical efficiency,and so on.In the modern era,when the urban rail transit develops rapidly,LIM wheel/rail transit system has been adopted by more and more countries.Traditional research of LIM wheel/rail transit system focuses on the lateral and vertical dynamic of single vehicle,which cannot truly reflect the dynamic interaction between vehicles and influence of traction and braking conditions on train dynamic characteristics.LIM wheel/rail transit system is different from ordinary subways in the train formation,traction characteristics and the formation of motor vehicles and trailers.Therefore,it is necessary to study the longitudinal dynamic characteristics.Based on the lateral-vertical dynamic model of a single vehicle,this paper realizes multisection vehicle formation by setting the coupler and longitudinal dynamic factors such as train traction conditions,train and trailer grouping,and so on.By carrying out the research on three-dimensional train-line coupling dynamic simulation,this paper analises the dynamic characteristics of the vehicle with different matching conditions of horizontal alignment design parameters.It can provide reference for further research on train-line dynamics of LIM wheel/rail transit system and perfection of line design specifications.This thesis has done some work as follows:(1)A single-section LIM vehicle-line dynamics model and three-,four-,five-,seven-group LIM train-line dynamics models were established.The train models were provided with coupler cushioning device and can realize variable speed operation.(2)The simulation calculated the dynamic response of the four-section train when passing through the curved section with track irregularity excitation.The differences in the dynamic performance between the vehicles in the train and the vibration characteristics of the linear motor were analyzed.It is found that due to the less restraint of the coupler on the front and rear vehicles,the comfortability and safety of the front and rear ends of the vehicles are worse than that of the central vehicles.(3)The paper simulated dynamic response of a single vehicle and three-,four-,five-,seven-section trains at a constant velocity through a curved section line.The effect of the number of vehicle marshalling on the dynamic performance of the train and the vibration characteristics of the LIM were analyzed.It is found that improving the number of vehicle marshalling can improve the dynamic performance of the train to some extent.(4)The dynamic response of trains running through a curved section without track irregularities was simulated and the dynamic characteristics of a LIM train equipped with trailers were analyzed.It is concluded that the dynamic indexes of motor vehicles are generally worse than trailers under speed changing conditions.(5)This paper calculated the dynamic response characteristics of four-section train under different matching conditions of horizontal alignment design parameters.The influences of the radius,superelevation,the length of the transition curve and train’s running speed on the dynamic response of the train and the LIM were analyzed.It is found that the selection range of each alignment design parameter determined by the simulation results is greater than the allowable range of the specification,which can provide reference for modifying the specification.