Semi‐active control of air suspension with auxiliary chamber subject to parameter uncertainties and time‐delay

• Published in: International journal of robust and nonlinear control Vol. 30; no. 17; pp. 7130 - 7149
• Main Authors: Zhang, Zhiyong, Wang, Jianbo, Wu, Wenguang, Huang, Caixia
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 25.11.2020; Wiley Subscription Services, Inc
• Subjects: Active control; Active damping; Air springs; air suspension; Chambers; Control systems; Energy consumption; H-infinity control; Linear matrix inequalities; Mathematical models; Orifices; Parameter robustness; parameter uncertainties; Parameter uncertainty; Passenger comfort; Performance enhancement; Robust control; semi‐active control; Stability; Stiffness; Suspension systems; Throttles; time delay; Time lag
• ISSN: 1049-8923; 1099-1239
• DOI: 10.1002/rnc.5169

Suspension systems are critical to the ride comfort and handling stability of vehicles, but traditional passive suspensions fail to achieve optimal performance in the two aspects. Semi‐active suspension controller changes the suspension stiffness or damping to improve the ride comfort and handling stability, which has the potential advantages of low energy consumption and high reliability. In this paper, the model of an air spring with an auxiliary chamber and a variable throttle orifice is proposed and the semi‐active control strategy of air suspension is carried out. The parameters of the air spring with auxiliary chamber are optimized to improve the performance when the control system fails and to increase the basic performance for semi‐active control. Based on the linear matrix inequality approach to robust H∞ control, the semi‐active control strategy of the air suspension is studied, in which parameter uncertainties and time delay are considered to improve control robustness. An inverse model of the air spring is then established to calculate the area of the variable throttle orifice, by which the desired control force is tracked accurately. Finally, the effectiveness of the semi‐active control system of the air suspension is verified by numerical simulation. Comparing with the passive suspension, not only under nominal parameters, but also with parameter uncertainties, time delay, and both parameter uncertainties and time delay, the semi‐active control system proposed in this paper has good control performance as well as is strong robustness to parameter uncertainties and time delay.