A supervised discrete adaptive control scheme with multiestimation

A discrete pole placement-based adaptive controller with multiestimation is synthesized for linear time-invariant plants. A higher level switching structure between the various estimation schemes is used to supervise the re-parameterization of the adaptive controller in real time. The basic usefulness of the proposed multiestimation scheme relies into the improvement of the adaptation transient behavior while robust closed-loop stability is proved even in the presence of unmodeled dynamics of sufficiently small sizes. The scheme becomes specifically attractive when the various estimators are adaptive identifiers for the plant which is being modeled as possessing different possible amounts of unmodeled dynamics including different nominal orders and parametrical uncertainties. The influence of free design parameters is discussed through exhaustively worked simulations.