An improved closed-loop stability related measure for finite-precision digital controller realizations

Author

Wu, J. ; Chen, S. ; Li, G. ; Istepanian, R.H. ; Chu, J.

Author_Institution

Nat. Lab. of Ind. Control Technol., Zhejiang Univ., Hangzhou, China

Volume

46

Issue

7

fYear

2001

fDate

7/1/2001 12:00:00 AM

Firstpage

1162

Lastpage

1166

Abstract

The pole-sensitivity approach is employed to investigate the stability issue of the discrete-time control system, where a digital controller implemented with finite word length (FWL), is used. A stability related measure is derived, which is more accurate in estimating the closed-loop stability robustness of an FWL implemented controller than some existing measures for the pole-sensitivity analysis. This improved stability measure thus provides a better criterion to find the optimal realizations for a generic controller structure that includes output-feedback and observer-based controllers. A numerical example is used to verify the theoretical analysis and to illustrate the design procedure

Keywords

closed loop systems; control system synthesis; digital control; discrete time systems; feedback; observers; poles and zeros; robust control; sensitivity analysis; closed-loop stability related measure; closed-loop stability robustness; finite word length; finite-precision digital controller realizations; observer-based controllers; output-feedback controllers; pole-sensitivity approach; Control systems; Current measurement; Design methodology; Digital control; Optimal control; Robust control; Robust stability; Stability analysis; Stability criteria; Subspace constraints;

fLanguage

English

Journal_Title

Automatic Control, IEEE Transactions on

Publisher

ieee

ISSN

0018-9286

Type

jour

DOI

10.1109/9.935076

Filename

935076