1993 Volume 29 Issue 4 Pages 401-410
In this paper, a decentralized adaptive tracking control is studied for a large-scale, discrete-time system which consists of N interconnected SISO subsystems {Si} (i=1, 2, …, N) with unknown parameters. Most of past studies treated the interconnections as a disturbance, assuming that they were relatively weak, and emphasis was placed on stability rather than control accuracy. To improve the control accuracy, a control strategy with following features is proposed, provided that a common information link among subsystems is available, which supplies to subsystems informations about input and output data of the system. In this method, the effects of interconnections from other subsystems are estimated and considered to generate a control in each subsystem. Furthermore, informations about the generators of the desired outputs of other subsystems are used to improve the tracking accuracy. A modified constant-trace type least-squares algorithm is employed to estimate system and interconnection parameters. The stability of overall systems is analyzed and the effect of relative magnitude of dead time in subsystems are investigated. The results are illustrated by computer simulations.
