Research On Model-free Control For Active Suspension System

The car has long been the main travel tool.The automobile industry has been in existence for hundreds of years.Improve the performance of the car at the same time,people on the comfort of the car requirements are getting higher and higher.Car suspension takes more and more attention by the automotive industry as an isolated road input and an important part of the vehicle shock absorption.Car suspension from passive suspension,to semi-active suspension,to active suspension,is continuously progressing.The structure of the car suspension is also becoming more and more complicated and the external disturbance of the car suspension is increasing.The menthod of designing a controller that requires an accurate mathematiccal model is becoming more and more difficult to use on an active suspension.In order to solve this difficulty,this paper presents the design idea of model-free active suspension controller.Using very little suspension information,is able to design a highly efficient active suspension controller.The model-free active suspension controller proposed in this paper includes the asymptotic stability controller and the finite time stability controller.Model-free asymptotic stability controller use extended state observer ESO to estimate the amount of uncertainty in the system and compensates for these state quantities.The method of linear feedback is used to track the active suspension accurately.Using Lyapunov function to prove the stability of the control algorithm.Finally,we verify the controller performance in experimental platform.Model-free finite time stability controller use time-delay estimation TDE to estimate system status and simplify the system model.Through a reasonable choice of sliding surface,to solve the singular value problem.The nonsingular terminal sliding-mode NTSM tracking controller has a fast convergence characteristic.So the active suspension use NTSM to design the suspension controller for reaching the desired system state in finite time.Finally,using the suspension experimental platform to verify the controller robust stability and superior performance.The two active suspension controllers designed in this paper have the characteristics of progressive performance.Using NTSM for the active suspension controller has faster tracking performance than the controller with ESO.Through the suspension experimental platform to verify the active suspension controller,compared to the passive suspension,with data curve and mean square value.Two kinds of controller has better performance.