Extended 2-Delay Model Reference Adaptive Controllers with Reduced Input Amplitude

Abstract

Recently, a discrete-time model reference adaptive controller for non-minimum phase systems, called a 2-Delay Model Reference Adaptive Controller (2D-MRAC), has been proposed. However, this method only ensures the asymptotic model-following at the sampling instances, and the inter-sampling responses of the controlled system are not taken into consideration. In this paper, two extensions of 2D-MRACs arc proposed- a 2D-MRAC with internal input model and one with zero phase 2-delay inputs. These 2D-MRACs can provide the control system with not only the model-following property but also more reduced input amplitude for all non-minimum phase plant and a class of the desired outputs.