Topological theory of 0/0 ambiguities in robust control

Author

Jonckheere, Edmond A. ; Ke, Nainn-Ping

Author_Institution

Dept. of Electr. Eng. Syst., Univ. of Southern California, Los Angeles, CA, USA

Volume

5

fYear

1997

fDate

10-12 Dec 1997

Firstpage

4354

Abstract

Allowing some uncertain parameters in the numerator and denominator polynomials of the loop function of a feedback system can result in 0/0 ambiguities at some uncertain points. This in turn could create discrepancies between the stability margins computed from the “value set” approach and the “Horowitz template” approach. In addition, in case of some “essential” ambiguities, the singularity set of the Nyquist map-crucially related to continuity of the margins-is structurally unstable and nearly impossible to compute

Keywords

Nyquist diagrams; feedback; polynomials; robust control; stability criteria; topology; uncertain systems; 0/0 ambiguities; Horowitz template; Nyquist map; denominator polynomial; essential ambiguities; feedback system; loop function; margin continuity; numerator polynomial; robust control; singularity set; stability margins; topological theory; uncertain parameters; value set; Algebra; Feedback loop; Frequency; Polynomials; Robust control; Robustness; Stability; Transfer functions;

fLanguage

English

Publisher

ieee

Conference_Titel

Decision and Control, 1997., Proceedings of the 36th IEEE Conference on

Conference_Location

San Diego, CA

ISSN

0191-2216

Print_ISBN

0-7803-4187-2

Type

conf

DOI

10.1109/CDC.1997.649545

Filename

649545