On subspace identification of cascade structured systems
2010 (English)In: Proceedings of the IEEE Conference on Decision and Control, IEEE , 2010, 2843-2848 p.Conference paper (Refereed)
In identification it is important to take a priori structural information into account in many applications, something that is difficult when using subspace methods. Here will study how to incorporate a special structure, a cascade structure with two subsystems. Two new methods are derived for estimating system with this structure. The problem when using subspace identification on cascade structured system is that the states from the first subsystem are mixed with states from the second subsystem via a unknown similarity transform. The first indirect method finds a similarity transform that takes the system back to a form such that the subsystems can be recovered. The second method uses the fact that the structure of the extended observability matrix is known for cascade systems. However, it only works when both subsystems have order one. In practice this is still a common case. The results of the two methods seem promising, as illustrated by applying the methods to a real process, the double tank process. The performance is comparable with state of the art methods. Finally the problem of optimal input design for cascade systems are introduced, and illustrated by a simple example. Â©2010 IEEE.
Place, publisher, year, edition, pages
IEEE , 2010. 2843-2848 p.
, 2010 49th IEEE Conference on Decision and Control, CDC 2010
Cascade structures, Cascade systems, Indirect methods, Observability matrix, Optimal input design, Real process, Special structure, State-of-the-art methods, Structural information, Structured systems, Sub-space methods, Subspace identification, Identification (control systems)
IdentifiersURN: urn:nbn:se:kth:diva-55388DOI: 10.1109/CDC.2010.5717248ISI: 000295049103048ScopusID: 2-s2.0-78751604189ISBN: 978-1-4244-7745-6OAI: oai:DiVA.org:kth-55388DiVA: diva2:471644
The 49th IEEE Conference on Decision and Control, Atlanta, GA, 15-17 Dec. 2010
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QC 201201312012-01-312012-01-022013-09-05Bibliographically approved