Premium
Analytical formulation to compute QFT bounds: The envelope method
Author(s) -
MartínRomero Juan José,
GilMartínez Montserrat,
GarcíaSanz Mario
Publication year - 2009
Publication title -
international journal of robust and nonlinear control
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.361
H-Index - 106
eISSN - 1099-1239
pISSN - 1049-8923
DOI - 10.1002/rnc.1424
Subject(s) - quantitative feedback theory , envelope (radar) , function (biology) , controller (irrigation) , computer science , control (management) , control theory (sociology) , mathematics , mathematical optimization , control system , robust control , engineering , telecommunications , agronomy , radar , evolutionary biology , artificial intelligence , electrical engineering , biology
This paper describes an analytical formulation to compute quantitative feedback theory (QFT) bounds in one‐degree‐of‐freedom feedback control problems. The new approach is based on envelope curves and shows that a QFT control specification can be expressed as a family of circumferences. Then, the controller bound is defined by the envelope curve of this family and can be obtained as an analytical function. This offers the possibility of studying the QFT bounds in an analytical way with several useful properties. Gridding methods are avoided, resulting in a lower computational effort procedure. The new formulation improves the accuracy of previous methods and allows the designer to calculate multivalued bounds. Copyright © 2009 John Wiley & Sons, Ltd.