| High-speed railway is the lifeblood of the national economic development.Its rapid development is closely related to national economy rise rapidly.In recent years,China’s highspeed railway technology has made great achievements in operation speed and coverage area,but it can not fully meet the challenges of the current situation.Therefore,for the purpose of preferable to adapt to the intricate operating environment and circumstances of high-speed railway and meet the requirements of higher control accuracy and better safety performance,it is of great significance to conduct research on high-speed train and its automatic driving technology.The primary study contents and innovation points of this paper can be generalized as follows:(1)The wheel and rail system model of high-speed train is constructed.Through describing the force of high-speed train driving process,the control forces in the driving process are understanded.In order to avoid idling and slipping endangering the safe operation of the train,the adhesion between wheel and rail are described.According to the adhesion theory,gear transmission characteristics and the force analysis of the train by Newton’s law,a more reasonable wheel and rail system model of high-speed train is constructed,which provides a reference for the further research on the control method of high-speed train.(2)An improved active disturbance rejection controller is created based on the wheel and rail model of high-speed train.The basic principle and components of ADRC(Active Disturbance Rejection Control,ADRC)technology are described.The ADRC controller is created to track the speed of the wheel and rail model of the train.The traditional ADRC algorithm based on nonlinear function is improved by using nonlinear smooth function,like hyperbolic sine function.Through the speed tracking comparison with PID controller and ADRC controller,it is verified that the improved ADRC controller created in this paper can observe and compensate the internal uncertainties and external disturbances of the train wheel and rail system model,and has strong anti-interference ability.It can realize the purpose of tracking the target speed curve and has good control effect.(3)An active disturbance rejection sliding mode controller is created and improved based on the wheel and rail model of the high-speed train.The principle of sliding mode control(Sliding Mode Control,SMC)algorithm is described,and a SM-ADRC is created to track the speed of the wheel and rail model of the train.In order to improve the chattering problem of sliding mode algorithm,an improved SM-ADRC controller is created by using the saturation function instead of the symbol function in the original controller.The control results of the sliding mode controller,the SM-ADRC controller and the improved SM-ADRC controller are compared by speed tracking experiment.It is verified that the controller has strong anti-interference ability and stable control torque output.It can improve the chattering problem and has strong robustness.In this paper,by studying the driving process of high-speed train and the adhesion characteristics between wheel and rail,the dynamic model of wheel and rail system is constructed.An improved ADRC controller and an improved SM-ADRC controller are created to control the train to track the established target speed curve.The effectiveness of the created controller is verified according to the speed tracking results. |
