Title :
Reduced-order controllers for the continuous-time H∞ control problem with unstable invariant zeros
Author_Institution :
Dept. of Commun. Eng., Okayama Prefectural Univ., Japan
Abstract :
This paper addresses the existence and design methods of reduced-order controllers for the continuous-time H∞ control problem with unstable invariant zeros in the state-space realization of the transfer function matrix from the control input to the controlled error or from the exogenous input to the observation output, where the realization is induced from a stabilizable and detectable realization of the generalized plant. This paper presents new controller degree bounds for the H∞ control problem, and provides new solutions to designing reduced-order controllers for the H∞ control problem with invariant zeros in the closed right half complex plane. When such unstable invariant zero exists (even it is an imaginary-axis zero), this paper shows that reduced-order controllers with order strictly less than the generalized plant order exist if the H∞ control problem is solvable. Moreover, LMI based methods for constructing the reduced-order controllers are given.
Keywords :
H∞ control; continuous time systems; control system synthesis; linear matrix inequalities; reduced order systems; transfer function matrices; H∞ control problem; LMI based method; continuous-time control; reduced-order controller; state-space realization; transfer function matrix; unstable invariant zero; Communication system control; Control systems; Design engineering; Design methodology; Design optimization; Error correction; Filtering theory; Stability; Systems engineering and theory; Transfer functions;
Conference_Titel :
American Control Conference, 2003. Proceedings of the 2003
Print_ISBN :
0-7803-7896-2
DOI :
10.1109/ACC.2003.1240440