C. Kral, F. Pirker:
"Rotor Eccentricity Detection of Induction Machines by Means of Torque Estimation";
Talk: SDEMPED, Gijon; 09-01-1999 - 09-03-1999; in: "Proceedings", (1999), 283 - 287.

This paper introduces an eccentricity detection technique which is based on the analysis of fault related torque modulations. Shaft torque can be estimated by means of a simple space phasor model, which evaluates the stator voltage equation. The amplitude of these modulations depends on the grade of rotor misalignment, while frequencies of the occurring torque disturbances depend on slip. The introduced monitoring method is based on a spatial evaluation technique, which avoids any Fourier analysis in the time domain. A special data clustering algorithm smooths appearing data. Furthermore the influence of rotor speed can be removed. Simulation results will demonstrate usefulness of the investigated detection technique.