Finite Frequency Robust Control for Electro-Hydraulic Servo Actuated Active Suspension System

In this paper, an Electro-Hydraulic Servo System (EHSS) actuating an active suspension system by employing finite frequency robust control method is presented. EHSS is popularly used in various industrial applications. However, parametric uncertainties are responsible for the response of such system to be unstable. In addition to that, the performance of such system is highly sensitive to external load disturbances. This paper thus, presents the identification of parametric uncertainties posed by unmodeled dynamics through a comprehensive mathematical model of EHSS. The modeling constraints are also investigated to propose a Finite Frequency Robust Control Strategy to actuate an active suspension system subjected to road disturbances. Simulation results are able to determine the trade-off between robust control and rejecting road disturbances at higher deflection frequencies using different performance criteria. As a consequence, these investigations show that the proposed controller could overcome the model uncertainties of EHSS for Robust Active Suspension.