| With the rapid development of High-Speed Train program in China, the safe and reliable operation of High-Speed Train has become the major concern. As the speed of the railway increases, Chinese railway has achieved the leap in development, the safety issue is becoming more and more important yet challenging to address. Wheel skid may take place, which would worsen the performance of braking system in general, Wheel lock and slip, the accident of train derailment and capsized would easily happen, or even endanger the train safety in some emergent situations. The designed control schemes can not only completely prevent possible wheel skid, but also effectively take full advantage of adhesion force. Advanced antiskid control of High-Speed Train plays an important role in enhancing train operation safety. With safety security of the train operation and enhancing performance of braking system, t High-Speed Train must be equipped with the corresponding antiskid control system.To make model more accurate, various anomaly factors such as varying and uncertain operation environment, unknown and time-varying the wheel/rail contact surface and unexpected geological hazards are taken into consideration in the modeling. Based on the established model, propose a neuro-adaptive antiskid control strategy using barrier Lyapunov function which has simple calculation and high practicability. The performance and robustness of control schemes are evaluated through computer simulation. The major work and concrete research achievement of the paper can be summarized as follow:Firstly, recommend the domestic and overseas actuality, and the progress of antiskid control, indicate practical significance for engaging in antiskid research of High-speed train.Secondly, introduce the fundamental theory of adhesion control, elaborate skid characteristic between different areas in the curve of adhesion characteristic, analyze the inherent relationship between the optimum slip ratio and reference slip ratio, and provide academic evidence for control strategy design in this paper.Thirdly, the time-varying properties of the system parameters, other factors such as unknown and uncertain system parameters, the external disturbance caused by changeful operation environment are considered, and the interaction between the front and rear wheel, establishing more accurate dynamic model for antiskid control of high-speed train.Fourthly, based on more precise dynamic model, puts forward a neuro-adaptive control strategy using barrier Lyapunov function. The proposed control strategy is made up by reference slip ratio generator and controller. With the adhesion observer and improved recursive least square method, reference slip ratio generator can deduce the optimum slip ratio, improving the accuracy of the adhesion force estimation and the optimum slip ratio derived effectively. The point needed to be emphasized is that the optimum slip ratio would not be choose for reference slip ratio, on the basis of the derived optimum slip ratio reference slip ratio is redesigned as a state constraint dynamic parameter for enhancing the precision and stability of control policy.Finally, this control schemes make practical slip ratio track reference slip ratio by means of adjusting brake torque, has good robustness against the uncertainties and the external disturbances considered in the modeling process. The proposed control strategy with simple structure and no need of complicated computations only demands little information about system parameters and dynamics. The performance of control schemes has verified through the simulation with imitating the operation condition of High-Speed Train.The experimental results show that the proposed control strategy can balance with non-skid property and adhesion utilization, prevent possible wheel skid completely, take full advantage of adhesion force effectively, and have better braking performance of the train with regulating the slip ratio of the wheel, the simulation have achieved ideal effect. |
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