Simultaneous Stabilization and Constant Reference Tracking of LTI,MIMO Systems

It is shown that any finite number of plants that belong to certain classes of multi‐input multi‐output systems with no zeros in the region of instability can be simultaneously stabilized using linear, time‐invariant integral‐action controllers. These plants may be stable or unstable and their poles are not restricted; they may also have any number of zeros in the stable region of the complex plane. The classes of systems under consideration include plants with blocking or transmission zeros at infinity. The common controller achieves asymptotic tracking of step‐input references with zero steady‐state error and has a low order transfer‐function. Systematic synthesis methods are presented, and a parametrization of all simultaneously stabilizing controllers with integral‐action is also provided.