A comparative assessment of two techniques for modal identification from power system measurements

Timothy James Browne, Vijay Vittal, Gerald Thomas Heydt, Arturo Roman Messina

Research output: Contribution to journalArticle

57 Scopus citations


Power system oscillatory behavior can be analyzed in terms of modes, expressed as exponentially modulated sinusoids, exhibited in signals measured on the system. These signals are driven by the behavior of a large, nonlinear, time-variant system. In this paper, two modal identification methods are examined comparatively: Prony analysis and a method based on the Hilbert transform. Considerable structural differences exist between the two methods. Prony analysis yields modes which are directly expressed as exponentially modulated sinusoids, whereas the Hilbert method provides a more general solution. Synthetic and measured signals are used in the comparison. Some general conclusions are drawn from the analysis of several signals, including two sets of measured field data.

Original languageEnglish (US)
Pages (from-to)1408-1415
Number of pages8
JournalIEEE Transactions on Power Systems
Issue number3
StatePublished - Aug 18 2008



  • Dynamics
  • Empirical mode decomposition (EMD)
  • Hilbert transforms
  • Hilbert-Huang method
  • Interarea oscillations
  • Power system dynamic stabilityPpower system measurements
  • Power systems
  • Prony analysis

ASJC Scopus subject areas

  • Energy Engineering and Power Technology
  • Electrical and Electronic Engineering

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