Equilibrium stability analysis by numerical simulations for a linear system with time-delayed control

Abstract

The work starts from the linearization of a nonlinear mathematical model of the electrohydraulic servomechanism with structural switching and delayed control. The delay, as well as the switching structure, can lead to instability and to the deterioration of the dynamic system performance. Between the different approaches to the delay problem, this article considers the predictive feedback method. The question of switching structure is herein treated empirically, aiming in the numerical simulation not to impose on the system a magnitude of the disturbance of the zero equilibrium that leads to switching by changing the sign of the state variable which is the displacement of the servovalve spool. Numerical simulations allow to highlight a critical delay, which is attested by comparison to an analytical method.

Keywords

• electrohydraulic servomechanism
• delayed control
• switching structure
• state predictive feedback
• discretization
• numerical simulation