Discrete multivariable systems order reduction via Schur decomposition

A novel technique for obtaining reduced-order dynamic models from high-order models is proposed. The technique uses Schur decomposition, which is an efficient and stable numerical procedure. Based on different assumptions about system modes, two methods for obtaining reduced-order models are developed. In the first method, the reduced model is derived directly from the Schur form. In the second method, it is necessary, in addition, to solve some algebraic equations to derive the reduced model. The order-reduction methods are applied to a discrete dynamic model