Research And Control Simulation Of Giant Magnetostrictive Actuator For High-speed Train Active Suspension

China's high-speed railway has achieved the great-leap-forward development.With the continuous improvement of the running speed of high-speed trains and the lightweight design of body structure,the vibration of the trains in the running process is aggravated,which has an extremely adverse impact on the running safety and stability of high-speed trains.With the development of suspension system anti-vibration actuators and active control technology,active suspension system will be an important direction of future suspension development because of its excellent anti-vibration performance.In this paper,theoretical and simulation studies are carried out on the problems encountered in the application of giant magnetostrictive actuator(GMA)to train active suspension system.The research work in paper can provide ideas and references for the application of GMA in vehicle suspension field and the design of active suspension system.Therefore,it is of great theoretical and practical significance to study the active suspension system based on the GMA.The passive suspension system,semi-active suspension system and active suspension system of train are compared and analyzed.At the same time,the performance of several suspension system anti-vibration actuators is studied.The GMA is proposed to be used in the active suspension system of train.On the basis of familiarity with the working mechanism and characteristics of GMA,according to the requirements of active suspension system for the output parameters of anti-vibration actuator,the structure scheme of the important components of GMA is designed through theoretical calculations,including the selection of GMM rod and the determination of geometric parameters,magnetic circuit,driving coil,pre-loading institutions,displacement amplifier mechanism,cooling device and the design proposal of driving power,which lays a foundation for subsequent actuator modeling analysis.In order to analyze the static characteristics of the actuator,the equivalent dynamic model of the actuator is established.The effects of hysteresis characteristics and yoke selection on the static output of the actuator are simulated and analyzed.The results show that the hysteresis ratio of the actuator structure is larger than that caused by the material characteristics of GMM rod when the external driving magnetic field is larger.In order to improve the static output performance of the actuator,the material with higher relative permeability should be selected for the yoke.In order to analyze the dynamic characteristics of the actuator,the transfer function dynamic mathematical model of the actuator is established,And the step response and frequency response of the actuator are analyzed.The results show that while the output performance of the actuator is satisfied,the dynamic responseperformance of the actuator can be improved by increasing the diameter of the GMM rod or reducing the length of the GMM rod.The simulation of the active suspension system based on GMA is carried out.Based on the dynamic model,the simulation model of active suspension system is established by Matlab-Simulink simulation software.By studying the suspension system control strategy,the fuzzy control strategy is selected to complete the fuzzy controller of active suspension system.The results show that the vibration reduction effect of GMA active suspension is much better than that of passive suspension.The amplitude,velocity and acceleration amplitude of vibration amplitude of vehicle body are obviously reduced.After adopting fuzzy control,the vibration response amplitudes are reduced,which improves the robustness of suspension system and verifies the effectiveness of the designed fuzzy controller.