Robust Controller Designs for Systems with Nonlinear Uncertainties

摘要

In this work, we revisit the robust stability margin optimization problem. Two robust controller designs are proposed for systems subject to bounded nonlinear time-varying uncertainty. The first method is a counterpart of the well known D-K iteration procedure for μ synthesis. The second method is a new one on the basis of a new bilinear matrix inequality (BMI) formulation. Comprehensive comparisons of the two methods are made and a numerical example is given to illustrate the results.