Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
A case study in model reduction of linear time-varying systems
2006 (English)In: Automatica, ISSN 0005-1098, E-ISSN 1873-2836, Vol. 42, no 3, 467-472 p.Article in journal (Refereed) Published
Abstract [en]

In this paper, the balanced truncation procedure is applied to time-varying linear systems, both in continuous and in discrete time. The methods are applied to a linear approximation of a diesel exhaust catalyst model. The reduced-order systems are obtained by using certain projections instead of direct balancing. An approximate zero-order-hold discretization of continuous-time systems is described, and a new a priori approximation error bound for balanced truncation in the discrete-time case is obtained. The case study shows that there are several advantages to work in discrete time. It gives simpler implementation with fewer computations.

Place, publisher, year, edition, pages
2006. Vol. 42, no 3, 467-472 p.
Keyword [en]
balanced-truncation, periodic-systems, error-bounds
National Category
Control Engineering
Identifiers
URN: urn:nbn:se:kth:diva-15437DOI: 10.1016/j.automatica.2005.10.016ISI: 000235471200012Scopus ID: 2-s2.0-31144457450OAI: oai:DiVA.org:kth-15437DiVA: diva2:333478
Note

QC 20111110

Available from: 2010-08-05 Created: 2010-08-05 Last updated: 2016-06-01Bibliographically approved
In thesis
1. Model Reduction for Linear Time-Varying Systems
Open this publication in new window or tab >>Model Reduction for Linear Time-Varying Systems
2004 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The thesis treats model reduction for linear time-varying systems. Time-varying models appear in many fields, including power systems, chemical engineering, aeronautics, and computational science. They can also be used for approximation of time-invariant nonlinear models. Model reduction is a topic that deals with simplification of complex models. This is important since it facilitates analysis and synthesis of controllers.

The thesis consists of two parts. The first part provides an introduction to the topics of time-varying systems and model reduction. Here, notation, standard results, examples, and some results from the second part of the thesis are presented.

The second part of the thesis consists of four papers. In the first paper, we study the balanced truncation method for linear time-varying state-space models. We derive error bounds for the simplified models. These bounds are generalizations of well-known time-invariant results, derived with other methods. In the second paper, we apply balanced truncation to a high-order model of a diesel exhaust catalyst. Furthermore, we discuss practical issues of balanced truncation and approximative discretization. In the third paper, we look at frequency-domain analysis of linear time-periodic impulse-response models. By decomposing the models into Taylor and Fourier series, we can analyze convergence properties of different truncated representations. In the fourth paper, we use the frequency-domain representation developed in the third paper, the harmonic transfer function, to generalize Bode's sensitivity integral. This result quantifies limitations for feedback control of linear time-periodic systems.

Place, publisher, year, edition, pages
Lund: Lund University, 2004. 174 p.
Series
Institutionen för reglerteknik, Lunds universitet, ISSN 0280-5316 ; 1071
Keyword
Model reduction, Linear systems, Time-varying systems, Error bounds, Frequency-domain analysis, Convergence analysis, Performance limitations
National Category
Control Engineering
Identifiers
urn:nbn:se:kth:diva-74698 (URN)
Public defence
2004-12-03, M:B, Maskinhuset, Lunds tekniska högskola, Lund, 10:15 (English)
Opponent
Supervisors
Note
QC 20120206Available from: 2012-02-06 Created: 2012-02-03 Last updated: 2012-02-06Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Authority records BETA

Sandberg, Henrik

Search in DiVA

By author/editor
Sandberg, Henrik
In the same journal
Automatica
Control Engineering

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 479 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf