SIMULTANEOUS STABILIZATION OF MULTIPLICATIVELY PERTURBED PLANTS

摘要

Necessary and sufficient conditions are obtained for simultaneous stabilizability of a given linear, time-invariant, multiinput multi-output nominal plant and a multiplicatively perturbed plant, where the multiplicative perturbation is stable. These conditions are derived from the general parity-interlacing-property applicable to any two arbitrary plants and are expressed explicitly in terms of the real-axis poles and zeros of the nominal plant and the perturbation. The class of perturbations for which simultaneous stabilization is achievable are characterized using these conditions. A special class of unknown diagonal perturbations is also considered and simultaneously stabilizing controllers are designed for the nominal plant under any such unknown perturbation. (C) 1997 Elsevier Science B.V. [References: 8]