Transient stability enhancement of multimachine power systems using nonlinear observer-based excitation controller

M. A. Mahmud*, M. J. Hossain, H. R. Pota

*Corresponding author for this work

Research output: Contribution to journalArticle

29 Citations (Scopus)


This paper presents an approach to design a nonlinear observer-based excitation controller for multimachine power systems to enhance the transient stability. The controller is designed based on the partial feedback linearization of a nonlinear power system model which transforms the model into a reduced-order linear one with an autonomous dynamical part. Then a linear state feedback stabilizing controller is designed for the reduced-order linear power system model using optimal control theory which enhances the stability of the entire system. The states of the feedback stabilizing controller are obtained from the nonlinear observer and the performance of this observer-based controller is independent of the operating points of power systems. The performance of the proposed observer-based controller is compared to that of an exact feedback linearizing observer-based controller and a partial feedback linearizing controller without observer under different operating conditions.

Original languageEnglish
Pages (from-to)57-63
Number of pages7
JournalInternational Journal of Electrical Power and Energy Systems
Publication statusPublished - Jun 2014
Externally publishedYes



  • Multimachine power systems
  • Observer-based excitation controller
  • Partial feedback linearization
  • Transient stability controller

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