SLIDING MODE CONTROL OF AIR SUSPENSION HEIGHT WITH DUAL-DEADBAND DESIGN

A high accuracy sliding mode height control method of air suspension is proposed through high-precision modeling and dual-deadband design. The main innovations include: Different from models with polytropic process hypothesis, a new nonlinear air chamber model based on thermodynamics was presented with dual control equations of temperature and pressure; Dual-deadband design was proposed for air suspension height control, in which double deadbands were coupled in order to increase the control accuracy and avoid frequent oscillation that was likely to occur in single-deadband design; A robust controller considering dynamic characteristics and influence of road disturbance as well as system parameter change was put forward based on sliding mode control theory. The effectiveness of high-precision model and sliding mode control strategy with dual-deadband design were verified with MATLAB/Simulink simulation.