This paper covers proposing a new noise reduction method and considering theoretically its effect on noise and vibration in induction motors.
Noise of small induction motors is mainly due to electromagnetic force. In most traditional small induction motors, electromagnetic force concentrates on a specific frequency by its even slot pitched rotor design. With structure‘s modes, this concentrated electromagnetic force gives rise to deadly noise and vibration. In order to make concentrating power distributed for wide frequency range, this paper proposes varied rotor slot pitches. The influence of this method on noise and vibration of induction motors is studied. To do this, appropriate uneven slot pitched rotors are made. Corresponding to each rotor, electromagnetic force and vibration at motor frame points is calculated. Fourier analysis is used for predicting the effects of varied rotor slot pitch to electromagnetic force and vibration of induction motors.
