Optimal wavelets for broken rotor bars fault diagnosis

This paper discusses the use of an optimal wavelets approach for broken rotor bars diagnosis. In this paper, discrete wavelet coefficients (DWT) of stator current in a specific frequency band are derived and analyzed. Wavelets db8, db9, db10, sym7 and sym8 are compared to select a most optimal one. This approach facilitates the detection and diagnosis of broken rotor bar occurrence or even number of broken bars under load variation. Simulation and experimental tests on inductions motors with 1, 2, and 3 broken bars are conducted, which demonstrate the effective fault detection of the proposed approach.