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Comparison of architectures and robustness of model reference adaptive controllers and L-1 adaptive controllers

Kharisov, Evgeny; Hovakimyan, Naira and Åström, Karl Johan LU (2014) In International Journal of Adaptive Control and Signal Processing 28(7-8). p.633-663
Abstract
The paper compares direct and indirect model reference adaptive controllers (MRAC) with the L-1 adaptive controller. The architectures of the closed-loop systems are first compared in a simple setting that clarifies the similarities and differences of the controllers. The indirect MRAC and the L-1 controller have identical state predictors, but they differ in the computation of the control signal, which in L-1 is carried out by solving a feedback loop. The special case, where the controllers only adapt to a parameter representing input disturbances, is discussed. In this case, the closed-loop system is linear, so it may not be appropriate to call the controllers adaptive. The special case does, however, give good insight into similarities... (More)
The paper compares direct and indirect model reference adaptive controllers (MRAC) with the L-1 adaptive controller. The architectures of the closed-loop systems are first compared in a simple setting that clarifies the similarities and differences of the controllers. The indirect MRAC and the L-1 controller have identical state predictors, but they differ in the computation of the control signal, which in L-1 is carried out by solving a feedback loop. The special case, where the controllers only adapt to a parameter representing input disturbances, is discussed. In this case, the closed-loop system is linear, so it may not be appropriate to call the controllers adaptive. The special case does, however, give good insight into similarities and differences of the controllers and the effects of various modifications. In particular, the analysis gives good understanding of the robustness properties. Copyright (C) 2013 John Wiley & Sons, Ltd. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
L-1 adaptive control, model reference adaptive control, robust control
in
International Journal of Adaptive Control and Signal Processing
volume
28
issue
7-8
pages
633 - 663
publisher
John Wiley & Sons
external identifiers
  • wos:000340387300005
  • scopus:84905234982
ISSN
0890-6327
DOI
10.1002/acs.2419
language
English
LU publication?
yes
id
a9b94e6c-1152-4588-bf8a-6cdb4181a7a5 (old id 4659345)
date added to LUP
2014-09-24 15:17:53
date last changed
2017-10-22 03:09:52
@article{a9b94e6c-1152-4588-bf8a-6cdb4181a7a5,
  abstract     = {The paper compares direct and indirect model reference adaptive controllers (MRAC) with the L-1 adaptive controller. The architectures of the closed-loop systems are first compared in a simple setting that clarifies the similarities and differences of the controllers. The indirect MRAC and the L-1 controller have identical state predictors, but they differ in the computation of the control signal, which in L-1 is carried out by solving a feedback loop. The special case, where the controllers only adapt to a parameter representing input disturbances, is discussed. In this case, the closed-loop system is linear, so it may not be appropriate to call the controllers adaptive. The special case does, however, give good insight into similarities and differences of the controllers and the effects of various modifications. In particular, the analysis gives good understanding of the robustness properties. Copyright (C) 2013 John Wiley & Sons, Ltd.},
  author       = {Kharisov, Evgeny and Hovakimyan, Naira and Åström, Karl Johan},
  issn         = {0890-6327},
  keyword      = {L-1 adaptive control,model reference adaptive control,robust control},
  language     = {eng},
  number       = {7-8},
  pages        = {633--663},
  publisher    = {John Wiley & Sons},
  series       = {International Journal of Adaptive Control and Signal Processing},
  title        = {Comparison of architectures and robustness of model reference adaptive controllers and L-1 adaptive controllers},
  url          = {http://dx.doi.org/10.1002/acs.2419},
  volume       = {28},
  year         = {2014},
}