Adaptive Speed Tracking Control Of High-speed Trains Based On Characteristic Model

At present,the rapid development of high-speed trains has contributed immeasurably to the promotion of national economic construction and social progress,and high-speed trains are increasingly become an important means of transportation for people because of their high transportation efficiency and comfortable and convenience ride.As a large transportation system that relates on the safety of passengers’ lives and property,the safe and reliable operation of high-speed trains are an essential fundamental.High-speed trains need to solve numerous and complex technical problems in the face of complex and diverse natural geographical and geological conditions and different transportation requirements,while meeting the objectives of high control accuracy and desired safety performance.Therefore,it is of great practical significance to study high-speed trains and their automatic driving technology in depth.The operation process of high-speed trains is taken as the research object in this thesis,for the complexity and variability of high-speed train dynamics system,the characteristic modeling idea in train dynamics is introduced for analysis,and an equivalent train characteristic model is established.Then,based on the proposed characteristic model and tracking control requirements,an adaptive sliding mode controller based on characteristic model is designed for high-speed train to track the target curve.On the basis of the train characteristic model,the train is considered to be affected by the system errors,the train characteristic model with system error is established,the system error is estimated based on the extended state observer(ESO),and the high-speed trains adaptive controller based on error compensation is designed to improve the train control accuracy.The simulation experiments demonstrate the effectiveness of the proposed control methods.The main research contents of this thesis are as follows:(1)To address the problems of nonlinearity,uncertainty and time-varying model parameters in train operation,a high-speed trains modeling method based on characteristic modeling is proposed by introducing characteristic modeling method into the traditional dynamics model in train dynamics analysis.A recursive least squares method is employed to identify the characteristic parameters of the train,which reduces the model complexity and makes the model more accurate.(2)In order to effectively deal with the problems of nonlinearity and uncertainty in train operation,an adaptive sliding mode controller based on the characteristic model of train errors,combined with the PID sliding mode surface and improved sliding mode convergence law to reduce the impact of jitter on the system,is designed based on the characteristic of sliding model control which is good at handling the uncertainties of the system and has strong robustness.The CRH380 A high-speed trains are used as the research object for experimental simulation,and the simulation results verifies the purpose of the designed controller to achieve asymptotic tracking on the given speed curve to ensure safe,reliable and smooth operation of high-speed trains.(3)On the basis of the train characteristic model,the influence of system errors on the train is further considered,a characteristic model of high-speed trains in the presence of system errors are established,the estimation capability of the dilated state observer for system errors are used to design an adaptive error compensation controller for high-speed trains based on the characteristic model,and the controller parameters are optimized by combining generalized minimum variance.The simulation results show that the control strategy can continue to achieve asymptotic tracking control for a given speed profile in the presence of system errors,effectively deal with the uncertainties caused by system errors,and improve the train control accuracy.