Research Of Mid-low Speed Maglev Track Step Recognition And Fluctuation Restrain Algorithm

Mid-low speed maglev is a new means of transportation,which has the advantage of low cost,low energy consumption,low noise and strong ability of climbing.It has been put into use in Changsha Maglev Express and Beijing S1 line.Currently,the construction of Beijing S1 line has almost accomplished and it is now in the procedure of joint testing.In the end of the year 2017,it will be put into use.While doing experiments in the test line,the phenomenon of track gap and steps due to the construction,change of temperature as well as other reasons exist.This phenomenon will decrease the dynamic performance of EMS maglev,even creates harmful influents on the stability of the system.Therefore,on one hand,the track needs to be precisely regulated,on the other hand,it is needed to focus on the control strategy and put forward a new control algorithm,in order to ensure that the system may not respond to the guideway step too fiercely and keep stable suspension.The dissertation is based on the Beijing S1 line.To begin with,the mathematic model of single-sided double points suspension system correlated with the rigid track is set up.PID feedback control is designed.And simulation of the dynamic performance on the condition of track gap and step is carried out.Then,the connections as well as the differences of sensor gap and corresponding gap are discussed;the corresponding gap is used in the feedback control of suspension system.While running,the method of gap recognition and compensation is discussed.Using the corresponding gap as the feedback parameter,the accelerated speed in z direction and the change rate of current is decreasing sharply.The antijamming capability of the system is increased.Finally,as the two suspension points are rigidly connected,the rotation in xoz plane may bring influences to both suspension points.A new decoupling control algorithm based on inversed system is carried out,which is able to decouple the suspension system into two independent linear systems.Using pole-placement method to create feedback control system and simulation is carried out.The results show that the fluctuation of suspension gap,accelerated speed in z direction as well as the change rate of current is decreased.To conclude,the research results show that this new control method is beneficial to overcome the disturbance of the track gap.At the same time,the corresponding control strategy needs to verify in the future.