MULTIOBJECTIVE H-INFINITY PROBLEMS - LINEAR AND NONLINEAR CONTROL

In this note, we compare the value of nonlinear and linear control for a multiobjective H-infinity control problem with a linear time-invari ant (LTI) plant. We show that if the H-infinity performance of a nonli near feedback controller is measured by the maximum incremental gain, the optimal achievable performance with nonlinear, time-varying contro l is identical to that achievable by LTI control. (C) 1997 Elsevier Sc ience B.V.