Application of higher order spectral analysis for rotor broken bar detection in induction machines

Detection and identification of induction machine faults through the stator current signal using higher order spectra analysis is presented. This paper proposes two higher order spectra techniques, namely the power spectrum and the slices of bi-spectrum used for the analysis of induction machine stator current leading to the detection of electrical failures within the rotor. Experimental signals have been analyzed highlighting that bi-spectrum results show their superiority in the accurate detection of rotor broken bars. Even when the induction machine is rotating at a low level of shaft load, the rotor fault detection is efficient.