Nonlinear hydropneumatic suspension active control method based on parameter uncertainty and external disturbance

Abstract

The invention provides a nonlinear hydropneumatic suspension active control method based on parameter uncertainty and external disturbance. The nonlinear hydropneumatic suspension active control method includes the steps that based on a Newton second law of motion and physical parameters of hydropneumatic suspension, a nonlinear hydropneumatic suspension dynamic model is established; a dynamic model of a servo valve is established based on physical parameters of the servo valve; and an adaptive sliding mode controller is established for the uncertain parameters and unknown disturbance of the nonlinear hydropneumatic suspension dynamic model and the dynamic model of the servo valve, parameters of the adaptive sliding mode controller are set, and control simulation is carried out based on the parameters of the adaptive sliding mode controller. According to the nonlinear hydropneumatic suspension active control method based on parameter uncertainty and external disturbance, the parametersof the controller can be adjusted under the condition that a hydropneumatic suspension system is suffered from parameter uncertainty and external disturbance, the fact that three indicators of the body vertical acceleration of the suspension, the suspension dynamic travel and the wheel dynamic load are all greatly improved can be ensured, and thus control performance of the suspension system is met.

Description

technical field [0001] The invention relates to the field of active control of oil-gas suspension, in particular to an active control method of nonlinear oil-gas suspension based on parameter uncertainty and external disturbance. Background technique [0002] As one of the important components of the vehicle, the suspension is the link connecting the body and the wheels, and has a very important impact on the driving of the vehicle. Oil-pneumatic suspension is a classification of suspension from the medium used, but from the perspective of control force, people generally classify oil-pneumatic suspension as passive suspension. This is because oil-pneumatic suspension generally does not involve control force, mainly airbags and There are changes in the structure. Compared with the traditional passive suspension, the oil-pneumatic suspension uses oil as the force transmission medium and gas as the elastic medium, which has obvious nonlinear stiffness and damping characteristi...

AI Technical Summary

Problems solved by technology

The existing oil-pneumatic suspensions are basically researches on passive suspensions, and there is a lack of research on active control of oil-pneumatic suspensions. Therefore, there are few control data and the control methods are not comprehensive enough.

[0007] 2. The accuracy of the servo valve control model is low

Although the modeling of the servo valve is considered in the modeling process, more emphasis is placed on the design of the controller. The modeling of the suspension itself is relatively simple. The stiffness and damping of the system are all linear models, so that the actual system is consistent with the linear ideal. Large errors between models make the actual reference significance too low

[0008] 3. Unable to cope with the influence of external disturbance and parameter uncertainty

During the driving process of the car, the oil-pneumatic suspension must have the influence of external disturbances on the suspension, and with the structural changes of the device, some dynamic parameters in the oil-pneumatic suspension will change, which will bring the active control of the oil-pneumatic suspension. here comes the difficulty

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