Study On Bogie Stability Control Of High-Speed Trains Based On Motor Active Suspensions

With the gradual development of our country’s railways towards high-speed,the hunting stability of high-speed train has attracted more attention.In the past,researchers improved the hunting stability of high-speed trains by optimizing the parameters of the first and second suspensions,but this often reduced the vehicle’s curve passing performance to a certain extent,and due to the wear of the wheels,the equivalent conicity of the wheels increased,resulting in some parameters gradually away from the optimal values.In order to take into account the hunting stability and curve passing performance of the vehicle,and it is expected that some suspension parameters are always kept in the optimal range,some scholars propose to apply active control to the traction motor to act as an ideal dynamic vibration absorber.On the basis of these researches,this paper carries out active control for the traction motor of high-speed train to improve the bogie’s hunting stability.The main work is as follows:(1)The dynamic equations of the bogie with motor passive suspensions were established.On this basis,the optimization design method of the passive suspension parameters of the motor was analyzed by simulation,and it was proposed that the optimization design of the motor suspension parameters had the problem of insufficient adaptability.(2)The control theory of motor active suspensions was studied,and the dynamic equations of the bogie based on the motor active suspensions were established.In order to study the ideal parameters of the dynamic vibration absorber,the hunting frequency of the bogie and minimum damping ratio of the system were analyzed.The results show that the optimal traverse frequency of the motor is always lower than the hunting frequency by 1～1.5 Hz and the optimal traverse damping ratio of the motor is selected as 0.5.On this basis,a feedback control strategy for the motor to simulate an ideal dynamic vibration absorber was proposed.(3)The adaptive control method of the motor active suspensions was studied,the characteristics of mainstream frequency detection methods and time delay compensation methods were analyzed,and the adaptive control method of motor active suspensions was proposed.The construction of the control module was completed in Simulink and the function of each module was verified.(4)A high-dimensional nonlinear electromechanical coupling dynamics model of high-speed train was established.The dynamic model was co-simulated with the control model built in Simulink,and the simulation results were compared with the motor passive suspensions to analyze the control effect of the motor active suspensions.