On-line parameter estimation of continuous-time systems using a genetic algorithm

유전알고리즘을 이용한 연속시스템의 온라인 퍼래미터 추정

  • Lee, Hyeon-Sik (Dept.of Control Instrumentation Engineering, Korea Maritime University) ;
  • Jin, Gang-Gyu (Dept. of Mechanical Information Engineering, Korea Maritime University)
  • 이현식 (한국해양대학교 제어계측공학과) ;
  • 진강규 (한국해양대학교 자동화. 정보공학부)
  • Published : 1998.02.01

Abstract

This paper presents an on-line scheme for parameter estimation of continuous-time systems, based on the model adjustment technique and the genetic algorithm technique. To deal with the initialisation and unmeasurable signal problems in on-line parameter estimation of continuous-time systems, a discrete-time model is obtained for the linear differential equation model and approximations of unmeasurable states with the observable output and its time-delayed values are obtained for the nonlinear state space model. Noisy observations may affect these approximation processes and degrade the estimation performance. A digital prefilter is therefore incorporated to avoid direct approximations of system derivatives from possible noisy observations. The parameters of both the model and the designed filter are adjusted on-line by a genetic algorithm, A set of simulation works for linear and nonlinear systems is carried out to demonstrate the effectiveness of the proposed method.

Keywords

References

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