The detection of coil shorting in induction motors by means of wavelet analysis

Mieczysław Zając,

Maciej Sułowicz


This paper presents the results of an analysis of signals recorded in different inter-turn short- circuit states in the stator windings of a squirrel-cage motor operating under a constant load. The analysis was carried out in a time-frequency domain using a simple orthonormal wavelet base that can be used in a real system without the need to acquire specialist software. The choice of analytical was associated with the existence of a periodic energy flow between adjacent frequency bands, thus making it difficult to diagnose the Fourier analysis. The aim of the study was to gather data necessary for the development of a real-time diagnostic system. Magnetic axial flux, the zero voltage signal, the short- circuit current, vibration acceleration, sound pressure, electromechanical torque, currents and phase voltages were tested as diagnostic criteria. The paper presents the main results of the analyses of magnetic axial flux signal and conclusions.

Słowa kluczowe: diagnostics of electromechanical systems, induction motor, short circuits, signal analysis, wavelet analysis