Implementability of Regulation and Partial Decoupling of MIMO Plants

Some necessary conditions of implementability of regulation of MIMO plant without and with integrators are formulated and proved in the paper. The notions of the join gain and degree of independence of the outputs of the plant in steady state are introduced. Partial decoupling of steady states and of fast transients is considered. The latter is based on an original approach consisting in transforming the decoupled matrix transfer function (MTF) of the plant to the form having on its diagonal the elements with smallest relative degree in each row. It is also shown that by the appropriate choice of the control saturations the decoupling of fast transients may be partially retained