# Sixty years of cybernetics: a comparison of approaches to solving the ${\text{H}}_{2}$ control problem

Kybernetika (2008)

- Volume: 44, Issue: 3, page 328-335
- ISSN: 0023-5954

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topKučera, Vladimír. "Sixty years of cybernetics: a comparison of approaches to solving the $\text{H}_2$ control problem." Kybernetika 44.3 (2008): 328-335. <http://eudml.org/doc/33931>.

@article{Kučera2008,

abstract = {The H2 control problem consists of stabilizing a control system while minimizing the H2 norm of its transfer function. Several solutions to this problem are available. For systems in state space form, an optimal regulator can be obtained by solving two algebraic Riccati equations. For systems described by transfer functions, either Wiener-Hopf optimization or projection results can be applied. The optimal regulator is then obtained using operations with proper stable rational matrices: inner-outer factorizations and stable projections. The aim of this paper is to compare the two approaches. It is well understood that the inner-outer factorization is equivalent to solving an algebraic Riccati equation. However, why are the stable projections not needed in the state-space approach? The difference between the two approaches derives from a different construction of doubly coprime, proper stable matrix fractions used to represent the plant. The transfer-function approach takes any fixed doubly coprime fractions, while the state-space approach parameterizes all such representations and those selected then obviate the need for stable projections.},

author = {Kučera, Vladimír},

journal = {Kybernetika},

keywords = {linear systems; feedback control; stability; norm minimization; linear systems; feedback control; stability; norm minimization},

language = {eng},

number = {3},

pages = {328-335},

publisher = {Institute of Information Theory and Automation AS CR},

title = {Sixty years of cybernetics: a comparison of approaches to solving the $\text\{H\}_2$ control problem},

url = {http://eudml.org/doc/33931},

volume = {44},

year = {2008},

}

TY - JOUR

AU - Kučera, Vladimír

TI - Sixty years of cybernetics: a comparison of approaches to solving the $\text{H}_2$ control problem

JO - Kybernetika

PY - 2008

PB - Institute of Information Theory and Automation AS CR

VL - 44

IS - 3

SP - 328

EP - 335

AB - The H2 control problem consists of stabilizing a control system while minimizing the H2 norm of its transfer function. Several solutions to this problem are available. For systems in state space form, an optimal regulator can be obtained by solving two algebraic Riccati equations. For systems described by transfer functions, either Wiener-Hopf optimization or projection results can be applied. The optimal regulator is then obtained using operations with proper stable rational matrices: inner-outer factorizations and stable projections. The aim of this paper is to compare the two approaches. It is well understood that the inner-outer factorization is equivalent to solving an algebraic Riccati equation. However, why are the stable projections not needed in the state-space approach? The difference between the two approaches derives from a different construction of doubly coprime, proper stable matrix fractions used to represent the plant. The transfer-function approach takes any fixed doubly coprime fractions, while the state-space approach parameterizes all such representations and those selected then obviate the need for stable projections.

LA - eng

KW - linear systems; feedback control; stability; norm minimization; linear systems; feedback control; stability; norm minimization

UR - http://eudml.org/doc/33931

ER -

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