Research On Modeling And Control Methods Of High-speed Train Active Suspension System

With the development of high-speed train technology,convenient and fast high-speed trains have become the first choice for people to travel.Suspension system,as an important part of the high-speed train,can attenuate the vibration of the train to a certain extent and improve ride comfort and operation safety.Compared with the traditional passive suspension system and semi-active suspension system,by applying external force,it can adjust in real time according to the actual operating conditions of the train,suppress the vibration of the train,and has fast response,low energy loss and simple structure.However,with the development of Railways toward high-speed and heavy-load direction,body vibration caused by track irregularity becomes increasingly prominent,which reduces the running quality of high-speed trains.Research on dynamic model analysis and intelligent control technology of train suspension system is one of the important ways to improve dynamic characteristics of train suspension system.It has become the research object of many scholars.In this paper,theoretical analysis and model simulation are combined to study active suspension system of high-speed train.Dynamic model and intelligent control algorithm of active suspension system are studied.The main research contents are as follows:(1)By comparing and analyzing the track spectrum in spatial domain of track irregularity at home and abroad,the German vertical low interference spectrum is taken as the external input excitation for the study of dynamic characteristics of suspension system of high-speed train,and the time domain transformation of the German vertical track irregularity is carried out by Fourier inverse transformation method.(2)Theoretical analysis on vertical vibration of 1/2 vehicle suspension system is carried out.Express train dynamic model of passive and active suspension system is established by reasonable simplified method.According to Newton’s second law,dynamic equation of 6-DOF of 1/2 vehicle is derived.The perling performance evaluation index of high-speed train is studied and the validity of vibration model of high-speed train suspension system is verified.(3)The control principles of fuzzy control,PID control and immune feedback control algorithm are respectively elaborated,On this basis,high-speed train active suspension controller models based on fuzzy control,fuzzy PID control and immune adaptive fuzzy PID control are designed respectively.Combining passive and active suspension dynamics models of high-speed trains,a simulation model of high-speed train suspension system is built in Matlab/Simulink software and simulated.The results show that all three control algorithms can restrain the vertical vibration of high-speed trains,and they can improve the comfort and maneuverability of trains to varying degrees.However,the combination effect of synthesis of immune adaptive fuzzy PID control is better.