STABILITY OF INPUT AMPLITUDE CONSTRAINED ADAPTIVE POLE-PLACEMENT CONTROL-SYSTEMS

This paper presents stability analysis for discrete time pole placemen t control system with input saturation constraints. It is shown that t he adaptive dosed-loop system for a class of stable type-m plants is g lobally stable in the sense that all the signals in the loop remain bo unded. It is also shown that certain degree of robustness with respect to modelling uncertainties and disturbances can be achieved for the a daptive control system by implementing a simple fixed dead zone in the parameter estimator. If the plant is free from modelling uncertaintie s and disturbances and the control input is not saturated for a finite period of time, then the dosed-loop adaptive control system will asym ptotically be characterized by the desired closed-loop poles within th is time period.