Research On Safety Braking Control Strategy For Medium Speed Maglev Train

With the rapid development of China’s economy and society,urban planning and construction have gradually shifted from the development of megacities to urban agglomerations with similar urban functions to alleviate the related problems brought by large cities.Intercity traffic plays an important role in increasing the internal relevance of urban agglomerations.Nowadays,in addition to intercity bullet trains,it is a new task for the development of China’s maglev traffic to develop a new medium speed maglev suitable for intercity traffic,which is of great significance to the development of China’s maglev traffic technology.Safety braking is a special braking method of maglev train,which can make the train stop stably in auxiliary parking area or station in case of emergency.Therefore,this paper studies the linear eddy current device used in safety braking and the safety braking control strategy combined with the setting requirements of auxiliary parking area,which has important engineering significance for the design of auxiliary parking area in vehicles and lines.The safety brake of medium-speed maglev train is composed of linear eddy current brake and skid brake.So this article first from the linear eddy current brake researches on the structure and principle of eddy current brake,and then introduces the control mode of train safety braking process,in order to establish the dynamics model of train safety brake,which trains in the safety brake linear continuous electromagnetic force produced by the eddy current brake characteristic curve is a key factor in the safety brake.This paper,by using the electromagnetic simulation software Ansoft Maxwell,according to the vehicle on the linear eddy current brake structure in which to establish simulation model,according to the eddy current braking process of the linear eddy current brake actuation process,consider different braking level-train running speed-the air gap value determines the various simulation condition,the simulation for each level of braking in the air gap-speed eigenvalue corresponds to produce electromagnetic force value.By analyzing the characteristics of the transverse joint structure in the eddy current braking device,the influence of the preload force and spring stiffness on the transverse movement of the eddy current braking device is considered,and the force equation is established.The electromagnetic force characteristic curves of each braking grade corresponding to each characteristic air gap value were obtained by using Hermite interpolation method.By studying the variation law of the air gap value corresponding to the transverse connection spring under different preload and stiffness values,the electromagnetic force characteristic curve of the air gap value at the stage when the air gap value remains unchanged and the air gap changes is obtained.Finally,the electromagnetic force characteristic curve between the electromagnetic force and the operating speed of each braking grade considering the process of variable air gap is obtained.Through the medium-speed maglev train running lines,a harsh natural environment and train fault of extreme stress analysis,to complete the solution of the maximum/minimum operation section,on the basis of the safety braking control strategy,auxiliary parking area length and the auxiliary parking space design principles,for auxiliary parking in the medium-speed maglev vehicle route design provides the basis of the theoretical calculation.Then,based on Matlab GUI platform,the software was written to simulate the real-time generation of the line operation diagram in the process of train safety braking,which verified the rationality of the design of auxiliary parking area and the safety braking control strategy,and ensured that the train could be parked in the auxiliary parking area or station if it implemented safety braking at any position of the line.