A method for designing digital multivariable industrial controller

A new method is proposed for designing cascade rational controllers for linear discrete time multivariable industrial systems using output feedback. The method is based on the principle of approximate model-matching as opposed to exact model-matching design procedures. A newly defined set of parameters called the approximate generalised time moments (AGTM) are used in the design procedure. The AGTMs of the closed-loop system with the unknown controller parameters are matched with those of a target function that embodies the desired industrial specifications to be met. This results in a set of linear algebraic equations that are solved to obtain the controller parameters. Successful application of the method to design a controller for a two-shaft turbojet engine is illustrated