Reduced-order two-parameter pLPV controller for the rejection of nonstationary harmonically related multisine disturbances

A reduced-order gain-scheduling controller based on two time-varying parameters for the rejection of harmonic disturbances with time-varying frequencies is presented. The frequencies are harmonically related and assumed to be known. The control design results in a discrete-time controller with an order which is two times the number of frequency components of the multisine disturbance. Two gain-scheduling parameters are used independently of the number of harmonic components and a triangle is considered as the polytope, therefore the controller is obtained by interpolation between three controllers calculated for the vertices of the polytope. The resulting controller structure is therefore very simple. Experimental results on an active vibration control test bed are used to validate the controller.