A NOVEL DERIVATION METHODOLOGY FOR POLYNOMIAL-LQ CONTROLLER-DESIGN

A simple derivation methodology for optimization of linear quadratic (LQ) controllers is presented in the discrete-time polynomial systems framework. A control-law variation, regarded as a potential feedforward from the innovations, is used. Orthogonality is evaluated in the frequency domain, by collectively cancelling unstable poles by zeros. The suggested method, summarized as a three-step scheme, is exemplified on a disturbance measurement feedforward and an output feedback problem. It is a simple, more direct alternative to the ''completing-the-squares'' approach.