Analysis And Optimization Of Anti-Rolling Device For Medium And Low Speed Maglev Vehicle

The medium-and-low-speed maglev vehicle is a new type of urban rail vehicle.The anti-rolling device is an important part of its levitation frame,and is mainly composed of the anti-rolling beam and the anti-rolling rod.On the one hand,the function of anti-rolling device is to suppress the rolling motion of the levitation frame.On the other hand,the left and right levitation modules have longitudinal displacements when the maglev vehicle negotiates the curve line.Therefore,the anti-rolling device connecting the left and right levitation modules is also a key device for decoupling the left and right modules,and its structure and function have an important influence on the vehicle operation safety and the running quality.Therefore,the research on anti-rolling device has a great significance for the performance improvement of medium-and-low-speed maglev vehicles.In this paper,the anti-rolling device of levitation frame for the electromagnetic-levitated medium-and-low-speed maglev vehicle is researched to explore the influence of the flexibility of anti-rolling beam and the layout of anti-rolling device on the running performance of the vehicle,and the optimal design of the device is obtained.This paper summarizes the development history and the research overview of maglev technology;the structural characteristics and working principle of the anti-rolling device are analyzed;a three-dimensional finite element model of the anti-rolling beam is established;the substructure of anti-rolling beam with reduced degrees of freedom is analyzed by ANSYS software;the multi-body dynamics rigid-flexible coupled model of medium-and-low-speed maglev vehicle which consists the flexible anti-rolling beam is established by SIMPACK software.Based on the established rigid-flexible coupled model,the dynamics performance of the vehicle with carbon steel anti-rolling beam,aluminum alloy anti-rolling beam and that with one set and two sets of anti-rolling devices are calculated and analyzed.The main conclusions are as follows:1)The functions of the anti-rolling device are mainly suppressing the rolling motion of the levitation frame and also realizing the decoupling of the left and right levitation modules.By theoretical analysis and simulation calculations,it is the most dangerous operation condition for the stress and deformation of anti-rolling beam and rod when the vehicle is non-levitated.It is recommended to clear the passengers when the vehicle is levitated in order to avoid making the car fall with full load.2)When the vehicle runs on a straight line,the running stability of the vehicle with carbon steel anti-rolling beam is slightly better than that with aluminum alloy beam.However,both of them fully meet the excellent stability limit requirements within the speed range.In addition,the calculation results of electromagnet vertical and lateral forces of the levitation frame with anti-rolling beams of the two material are similar,and the condition of the first levitation frame is relatively poor.3)When the vehicle negotiates the 50m-radius horizontal curve line,the maximum lateral rolling angle and the maximum displacement of air spring for the vehicle with carbon steel anti-rolling beam are slightly larger than those with aluminum alloy beam.But the calculation results of both are within the allowable range.In addition,the selection of the material of anti-rolling beam has little effect on the vertical force of the beam and the lateral displacement of electromagnet.Therefore,using the aluminum alloy anti-rolling beam which has a lower weight and a lower cost can ensure the vehicle operation safety and quality.4)For the HSST-type maglev vehicle,on the straight line,the force of anti-rolling rod of each levitation frame generally decreases as the distance between anti-rolling beams and the distance beam the rods increase.On the curve line,the vertical force of anti-rolling rod also decreases as the distance between beams increases.Therefore,it is recommended to further increase the installation distance of the two sets of anti-rolling beams in the same levitation frame within the allowable installation space.5)Compared with the HSST-type levitation frame with two sets of anti-rolling devices and 4 end-set small air springs,the levitation frame of the new medium-and-low-speed maglev with one set of anti-rolling device and two mid-set large air springs has sufficient anti-rolling capability and better decoupling ability,so the use of one set of mid-set anti-rolling device is a better choice.