Fractional robust control of a nonlinear plant : Control of a nonlinear testing bench using the singular perturbation technique and the CRONE approach

Abstract

The control of a hydraulic testing bench is presented by using both singular perturbations technique and Crone control (fractional robust control). The testing bench is constituted of a hydraulic actuator which deforms, with a required velocity, the uncertain mechanical structures to be tested. Thanks to the singular perturbations techniques, the plant can be linearized despite the uncertainty by using a simplified input-output linearization under diffeomorphism and feedback. The Crone control is used to reject remaining nonlinearities considered as perturbations and to control the actuator velocity while taking into account the parametric variations of the mechanical structures.