“Estimation of Synchronous Machine Parameters”

Authors: Oddvar Hallingstad,
Affiliation: Norwegian Defence Research Establishment (FFI)
Reference: 1980, Vol 1, No 1, pp. 1-15.

Keywords: Maximum likelihood estimation, identifiability, short circuit measurement, transient stability model, parameter estimation

Abstract: The present paper gives a short description of an interactive estimation program based on the maximum likelihood (ML) method. The program may also perform identifiability analysis by calculating sensitivity functions and the Hessian matrix. For the short circuit test the ML method is able to estimate the q-axis subtransient reactance x´´q, which is not possible by means of the conventional graphical method (another set of measurements has to be used). By means of the synchronization and close test, the ML program can estimate the inertial constant (M), the d-axis transient open circuit time constant (T´do), the d-axis subtransient o.c.t.c (T´´do) and the q-axis subtransient o.c.t.c (T´´qo). In particular, T´´qo is difficult to estimate by any of the methods at present in use. Parameter identifiability is thoroughly examined both analytically and by numerical methods. Measurements from a small laboratory machine are used.

PDF PDF (1968 Kb)        DOI: 10.4173/mic.1980.1.1

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  title={{Estimation of Synchronous Machine Parameters}},
  author={Hallingstad, Oddvar},
  journal={Modeling, Identification and Control},
  publisher={Norwegian Society of Automatic Control}