A Structurally Stable Globally Adaptive Internal Model Regulator for MIMO Linear Systems

The problem of compensating an uncertain disturbance and/or tracking some reference signals for a general linear MIMO system is studied in this work using the robust regulation theory frame. The disturbances are assumed to be composed by a known number of distinct sinusoidal signals with unknown phases, amplitude and frequencies. Under suitable assumptions, an exponentially convergent estimator of the unknown disturbance parameters is proposed and introduced into the classical robust regulator design to obtain an adaptive controller. This controller guarantees that the closed-loop robust regulation is attained in some neighborhood of the nominal values of the parameters of system. A simulated example shows the validity of the proposed approach.