Performance level and stability margins of an optimal H-infinity flow controller


ÜNAL H. U., İFTAR A.

TRANSACTIONS OF THE INSTITUTE OF MEASUREMENT AND CONTROL, vol.34, no.7, pp.914-924, 2012 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 34 Issue: 7
  • Publication Date: 2012
  • Doi Number: 10.1177/0142331211425402
  • Journal Name: TRANSACTIONS OF THE INSTITUTE OF MEASUREMENT AND CONTROL
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.914-924
  • Keywords: Flow control, H-infinity-optimal control, infinite-dimensional systems, performance level, robust control, stability margins, COMMUNICATION-NETWORKS, BOUNDARY CONTROL, HEAT-FLOW, SYSTEMS, DESIGN
  • Anadolu University Affiliated: Yes

Abstract

Flow controllers are needed to avoid congestion in different types of networks. The dynamics of such networks, however, can usually be represented by infinite-dimensional models, which are either based on partial-differential equations or delay-differential equations. An optimal H-infinity flow controller design approach has recently been proposed for networks whose dynamics involve multiple and uncertain time-varying time delays. In the present paper, performance level and stability margins of controllers designed by this approach are analyzed. It is shown that, by choosing certain controller design parameters large, stability margins can be improved; while choosing them small improves performance levels. Therefore, there is a clear trade-off between robustness and performance.