Stable model reference adaptive control for periodically LTV systems based on the maximal error evaluation

Abstract

This paper presents a model reference adaptive control system (MRACS) which does not depend on the degree of the plant when the plant is the continuous-time periodically linear time varying (LTV) system. A priori information is only the relative degree and the time-varying period. The controller has adjustable scalar functions. The optimal functions of these are estimated directly, synchronizing with the time-varying period of the plant by adaptive laws. The main contribution of this paper is that the computational burden of the adaptive law for the direct function estimation is reduced. It is accomplished with the maximum normalized error evaluation typed adaptive law. The design method and the global stability analysis of the proposed system are shown and a simple numerical simulation result is indicated to verify the viability of the proposed system.