Detection of Rotor Bar Fault through Stray Flux Based Analytical Signal Angular Fluctuation Method

Stray flux analysis has increasing trend to monitor the machine condition including fault diagnosis. In this paper, the rotor bar fault is detected through the Stray Flux based Analytical Signal Angular Fluctuation (SF-ASAF) method in induction motors (IMs). For this purpose, the stray flux is collected from the vicinity of motor frame and analytical signal of stray flux is calculated using Hilbert Transform (HT). Then, angular fluctuation of obtained signal is utilized to see the harmonic content of stray flux-analytical signal. It is shown that there are some effective signals such as f
s
-3sf
s
, 2sf
s
to detect rotor bar fault in stray flux based analytical signal angular fluctuation spectrum. The presented 2D-FEM based simulation and experimental results prove that the Stray Flux based Analytical Signal Angular Fluctuation (SF-ASAF) method can provide superior and reliable results rather than classical stray flux analysis in induction motors.