Research On Nonlinear Motion Control Of High-speed Trains Based On Terminal Sliding Mode

Railway transportation,as a fundamental and strategic industry in the country,has significant significance in promoting national economic construction and social development.With the increasing and diversified demand for travel by the public,high-speed railways in China have developed rapidly,which is reflected in the continuous improvement of the operating speed of high-speed trains and the gradual increase in operating density.This puts forward higher requirements for the safety and control accuracy of the current high-speed train control system.In order to ensure that high-speed trains can operate safely and at the same time achieve high precision tracking of target velocity displacement,this paper investigates highspeed train motion control.The main work content is as follows:(1)A terminal sliding mode tracking controller based on Radial Basis Function(RBF)network and disturbance observer is designed for a single mass point motion model of highspeed trains with nonlinearity,model uncertainty and external disturbance.For the nonlinear train motion model,the sliding mode surface of displacement and velocity tracking error is given,and the train tracking controller is designed using a non-singular fast terminal sliding mode method to ensure that the train motion state tracks on the target curve in a finite time;Introducing RBF neural networks to estimate the nonlinear basic resistance of trains,giving an adaptive law for neural network weights;designing a nonlinear disturbance observer based on differential tracker to estimate the nonlinear disturbances suffered by trains,eliminating the approximation errors of RBF networks and the effects caused by unknown disturbances during train operation,and enhancing the anti-disturbance capability of trains.The estimator and observer are designed into the controller to compensate the system,and Lyapunov stability analysis ensures that the variables of the closed-loop system are consistent and eventually bounded;computer simulations verify the effectiveness and feasibility of the designed control scheme.(2)A terminal sliding mode high-speed train multi-particle tracking controller based on a high-gain observer is designed for a high-speed train multi-particle motion model with model nonlinearity and unmeasurable velocity signals.Designing a multi-particle train model state observer based on high gain observer to observe the operating state of high-speed trains and solve the problem of unmeasurable speed signals of multi-mass trains;Designing a non-singular fast terminal sliding surface for multi-particle train tracking errors incorporating state observers;Design a terminal sliding mode multi-particle train tracking controller based on high gain observer requiring only train position information;Constructing Lyapunov alternative functions containing observation and tracking errors,Lyapunov stability analysis ensures that the variables of the closed-loop system are asymptotically stable;Computer simulations verified the effectiveness and feasibility of the designed state observer and tracking controller.