“An Algorithm for Design of Decentralized Suboptimal Controllers with Specified Structure”

Authors: David Di Ruscio and Jens G. Balchen,
Affiliation: NTNU, Department of Engineering Cybernetics
Reference: 1990, Vol 11, No 3, pp. 155-167.

Keywords: Control system design, decentralized control, linear optimal control, optimization

Abstract: In this paper we present a method for the design of controllers with a specified arbitrary structure for linear multivariable time invariant systems. Both decentralized controllers as well as feedback from a reduced state vector can be designed by this method. The controller will become optimal in the sense that it yields a minimum of a quadratic cost criterion and suboptimal in the sense that it yields a higher value of this criterion than a controller without restrictions. The algorithm makes it possible to specify a stability margin on the feedback system. This means that the feedback system will have eigenvalues located to the left of a certain line (-alpha) in the complex plane. The unknown parameters of the controller are collected in a parameter vector. The algorithm is based upon a modified Newton-method for searching towards the ´optimal´ parameter vector. The algorithm ensures that the closed loop system is stable at any iteration in the case of an initially stable plant, and after the final iteration in the case of an initially unstable plant.

PDF PDF (1552 Kb)        DOI: 10.4173/mic.1990.3.3

DOI forward links to this article:
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  title={{An Algorithm for Design of Decentralized Suboptimal Controllers with Specified Structure}},
  author={Di Ruscio, David and Balchen, Jens G.},
  journal={Modeling, Identification and Control},
  publisher={Norwegian Society of Automatic Control}