화학공학소재연구정보센터
IEEE Transactions on Automatic Control, Vol.50, No.9, 1369-1374, 2005
Optimizing simultaneously over the numerator and denominator polynomials in the Youla-Kucera parametrization
Traditionally, when approaching controller design with the Youla-Kucera parametrization of all stabilizing controllers, the denominator of the rational parameter is fixed to a given stable polynomial, and optimization is carried out over the numerator polynomial. In this note, we revisit this design technique, allowing to optimize simultaneously over the numerator and denominator polynomials. Stability of the denominator polynomial, as well as fixed-order controller design with H-infinity performance are ensured via the notion of a central polynomial and linear matrix inequality (LMI) conditions for polynomial positivity.