Rejection of narrow-band disturbances subject to uncertain time-delays

In English In this work, the problem of designing feedback controllers for the rejection of narrow-band disturbances is considered. The design technique proposed herein is based upon the overparameterization of a nominal minimum-variance controller, which is designed by means of an ARMA model of a sinusoid in noise. The extra degrees of freedom so introduced are used to improve the robustness of the nominal controller, when the time delay of the plant is subject to uncertainties, by minimizing a minimum-variance performance index along a one-dimensional line.