Adaptive Control Design for SISO Plants with Input Delays and Unmeasured Perturbations

Abstract

Time delay is a phenomenon often encountered in control system designs. Most typically, the delayed systems emerge in transport, communications, chemical processes and power systems. Control of such systems is a difficult problem even in the deterministic settings, not talking about the situations when the parameters of the system are either not completely defined, or they change their values in the process of functioning. In this paper, a new reference model of the adaptive control scheme is proposed for the plans with an input delay and unmeasured perturbations, including some new adaptive control algorithms in the class of systems with an auxiliary model and enhanced error. The synthesized algorithms guarantee stability of the closed control system. Achievement of the control target is ensured by the presence of a closed loop signal with a rich spectrum, otherwise a dissipation system. Application of this scheme allows a reduction of the number of the adjustable parameters of the adaptive controller down to the number of the unknown coefficients of the system. The proposed structure of the adaptive control contains only units with lumped delays, which considerably simplifies implementation of such systems in practice.