Pseudo desired plant approach to the synthesis of almost decoupling control

This paper proposes the pseudo desired plant approach to the almost decoupling control problem. The internal stability of the compensated system is indispensable for most of all control syntheses. The exact decoupling will induce either pole-zero cancellations of the hidden modes or the McMillan degree of the compensator. It causes the problem of the internal stability if there exist transmission zeros. Therefore, the almost decoupling control synthesis is addressed. This controller makes the compensated system both internally stable and almost decoupled. The algorithm of the almost decoupling control synthesis is also provided. In addition, an example is given to illustrate the applicability of the algorithm.