{"title":"Implicit restart scheme for large scale Krylov subspace model reduction method","authors":"N. Ahmed, M.M. Awais","doi":"10.1109/INMIC.2001.995327","DOIUrl":null,"url":null,"abstract":"An implicitly restarted Krylov subspace model reduction method is presented. By this technique a stable, linear transfer function f(s) of order n can be approximated by an order m, where n/spl Gt/m. The oblique projection of stable systems onto a Krylov subspace may generate unstable partial realizations along with undesirable modes. To ensure that the Krylov projected model for a stable system is also stable and contains useful modes only, further operations like stable projection and balanced truncation are then performed to compute a reduced order model f/sub r/(s) of order r (where r<m), which approximates more accurately the original system. This all is imperative because the robust controller design methods based on the small gain theorem require that the actual model f(s)and the nominal model (f,(s)) have the same number of poles in the closed right half complex plane It can be realized that both these projections may be combined as a single oblique projection and this whole process can be fitted into an implicit restart framework. The behavior of the developed algorithm is illustrated by taking a large-scale system. Finally, a criterion for the selection of an accurate reduced order model approximation is proposed for large-scale systems.","PeriodicalId":286459,"journal":{"name":"Proceedings. IEEE International Multi Topic Conference, 2001. IEEE INMIC 2001. Technology for the 21st Century.","volume":"11 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"2001-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"4","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Proceedings. IEEE International Multi Topic Conference, 2001. IEEE INMIC 2001. Technology for the 21st Century.","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/INMIC.2001.995327","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 4
Abstract
An implicitly restarted Krylov subspace model reduction method is presented. By this technique a stable, linear transfer function f(s) of order n can be approximated by an order m, where n/spl Gt/m. The oblique projection of stable systems onto a Krylov subspace may generate unstable partial realizations along with undesirable modes. To ensure that the Krylov projected model for a stable system is also stable and contains useful modes only, further operations like stable projection and balanced truncation are then performed to compute a reduced order model f/sub r/(s) of order r (where r