Linear approximation model network and its formation via evolutionary computation

Yun Li, Kay Chen Tan

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

To overcome the deficiency of 'local model network' (LMN) techniques, an alternative 'linear approximation model' (LAM) network approach is proposed. Such a network models a nonlinear or practical system with multiple linear models fitted along operating trajectories, where individual models are simply networked through output or parameter interpolation. The linear models are valid for the entire operating trajectory and hence overcome the local validity of LMN models, which impose the predetermination of a scheduling variable that predicts characteristic changes of the nonlinear system. LAMs can be evolved from sampled step response data directly, eliminating the need for local linearisation upon a pre-model using derivatives of the nonlinear system. The structural difference between a LAM network and an LMN is that the overall model of the latter is a parameter-varying system and hence nonlinear, while the former remains linear time-invariant (LTI). Hence, existing LTI and transfer function theory applies to a LAM network, which is therefore easy to use for control system design. Validation results show that the proposed method offers a simple, transparent and accurate multivariable modelling technique for nonlinear systems.

LanguageEnglish
Pages97-110
Number of pages14
JournalSadhana - Academy Proceedings in Engineering Sciences
Volume25
Issue number2
DOIs
Publication statusPublished - 1 Apr 2000

Fingerprint

Evolutionary algorithms
Nonlinear systems
Trajectories
Step response
Linearization
Transfer functions
Interpolation
Systems analysis
Scheduling
Derivatives
Control systems

Keywords

  • modelling
  • system identification
  • linear approximation model
  • networks
  • evolutionary computation
  • local model networks

Cite this

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Linear approximation model network and its formation via evolutionary computation. / Li, Yun; Tan, Kay Chen.

In: Sadhana - Academy Proceedings in Engineering Sciences, Vol. 25, No. 2, 01.04.2000, p. 97-110.

Research output: Contribution to journalArticle

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