Two-degree-of-freedom controller design for an ill-conditioned distillation process using mu-synthesis

The structured singular value framework is applied to a distillation benchm ark problem formulated for the 1991 IEEE Conference on decision and control (CDC). A two degree of freedom controller, which satisfies all control obj ectives of the CDC problem, is designed using mu-synthesis. The design meth odology is presented and special attention is paid to the approximation of given control objectives into frequency domain weights.