Gain-scheduling compensator synthesis for output regulation of nonlinear systems

This paper addresses the gain-scheduling output regulation synthesis problem for nonlinear systems. For gain-scheduling control, the linear parameter-varying (LPV) model is obtained from nonlinear plant by plant linearization about zero-error trajectories upon which an LPV controller is synthesized. In practical engineering application, a key issue is to find a nonlinear output feedback compensator related to the designed LPV controller which can guarantee that the closed-loop system of nonlinear plant and compensator linearizes to the interconnection of LPV model and LPV controller. So the stability and performance about the zero-error trajectories can be inherited when the nonlinear compensator is implemented. By incorporating equilibrium input and measured output into the auxiliary LPV model, the compensator synthesis problem is reformulated as linear matrix inequalities (LMIs) which can be solved efficiently using the interior-point method. Consequently the proposed output feedback compensator can satisfy the linearization requirement. Finally, the validity of the proposed approach is demonstrated through a ball and beam design example.