Title :
A simple method for L2 approximation of unstable and nonminimum-phase systems
Author :
Zhou, Ping ; Chai, Tianyou ; Wu, Yanlin
Author_Institution :
Autom. Res. Center, Northeastern Univ., Shenyang, China
Abstract :
A simple performance-oriented method is proposed for approximation the unstable and nonminimum-phase systems. The performance index is taken to be a frequency-domain L2-norm of the error between the step responses of the original and the reduced model. A frequency-domain weighted recursive least squares (RLS) algorithm is deduced and adopted to search for the optimal parameters of the approximation model. A numerical example is used to show the effectiveness of the proposed scheme. It is shown that the approximation models obtained by the proposed scheme yield zero steady-state gain errors and have the same RHP pole and RHP zero as the original system, resulting in well-matched dynamic behavior.
Keywords :
approximation theory; least squares approximations; recursive estimation; L2 approximation; RHP pole; RHP zero; frequency-domain L2-norm; nonminimum-phase systems; optimal parameters; recursive least squares algorithm; unstable systems; Approximation algorithms; Approximation error; Approximation methods; Frequency; Least squares approximation; Performance analysis; Poles and zeros; Reduced order systems; Resonance light scattering; Steady-state; Frequency-Domain Weighted Recursive Least Squares (RLS); L2 Approximation; Model reduction; Unstable and/or Nonminimum-Phase Systems;
Conference_Titel :
Control and Decision Conference (CCDC), 2010 Chinese
Conference_Location :
Xuzhou
Print_ISBN :
978-1-4244-5181-4
Electronic_ISBN :
978-1-4244-5182-1
DOI :
10.1109/CCDC.2010.5498757
