Research On Hign-Speed Vehicle Semi-Active Suspension Systems Control Strategy

The running stability and riding comfort of the railway vehicle are decided by the vibration control effect of suspension control system. Design optimization method for the vehicle suspension system is an effective approach to damp lateral vibration and improve lateral ride quality, which is beneficial to the high-speed train project in our country.The semi-active suspension system of high-speed train is simple, low power consumption, dependable, safe; which has become a focal point of research in high-speed railway vehicle intellectual suspension control. The intelligent control methods and the theory of railway vehicle dynamics are applied to optimize the design and make simulation research. Some researches in this thesis have been done as follows:1,The control principles and related characteristics of the passive suspension system and active or semi-active suspension control system are specified. The necessity of the high-speed train semi-active suspension system is analyzed, a variety of semi-active suspension control strategies are regarded object in this thesis2,This thesis had a detailed analysis of track irregular and simulates the German low interference and high-speed track spectrum analog signal based on the power spectral density of sampling method. The 17 degrees lateral application simulation model of the high-speed railway vehicle are built by MATLAB/Simulink in this thesis based on the mechanism of train random vibration and Differential Equation of Motion of high-speed railway vehicle.3,In accordance with the complexity of high-speed railway vehicle suspension system, the 3 degrees controlled CARIMA model of the half vehicle and the algorism of Step Generalized Predictive Control strategy (SGPC) are applied to design the high-speed train semi-active suspension control system in the thesis. At last, simulation research based on the riding comfort index has been made to evaluate the control effect.Simulation results demonstrate that the semi-active suspension control system of railway vehicle based on SGPC can effectively suppressed the lateral vibration. The lateral stability Sperling index of high-speed train decreases 18%, and the maximum and the root mean square value of the train body lateral acceleration largely decreases comparing with the optimal vibration damping state of passive suspension system. In addition, the thesis analysis the change of the lateral stability Sperling index and the root mean square value of train body lateral acceleration based on different speeds. The lateral stability Sperling index of railway vehicle increases with the speed increasing from 280 km/h～360 km/h, but the Sperling index of semi-active suspension control system still decreases 17% comparing with the passive suspension system. So Step Generalized Predictive Control strategy has better stability and robustness.This work is supported by the project of railway vehicle active suspension control in Traction Power State Key Laboratory of Southwest Jiaotong University.