Controller design for partial decoupling of linear multivariable systems

In this paper we present a controller design method which achieves partial (or one-way) decoupling for stable, linear time-invariant square MIMO plants. The method utilizes a factorization of the plant transfer matrix provided by a generalized interactor matrix, which contains a representation of the nonminimum phase and infinite zero structure of the plant. In the proposed method, a single scalar tuning variable permits the speed of closed-loop response to be traded-off against transient interactions between loops, and diagonal decoupling is achieved as a special case