An investigation on acoustic noise emitted by induction motors due to magnetic sources

As verified by industrial investigations, magnetic noise stands for a large percentage of noise emission in induction machines. The objective of this paper is to provide a study on existing methods for recognition of magnetic-related noise sources in induction motors. These magnetic noises are mostly originated from saturation harmonics, variable magnetic resistance of air-gap due to static and dynamic eccentricity, and the most important and common factor, rotor and stator slot combination. Thereby, this paper presents a systematic approach for gathering all the existing procedures to make them more useful in a more applicable way of designing and improving electrical induction motors.