Reduction of vibration and noise in low speed Direct-driven PMSMs

Stator excitation and the radial electromagnetic force acted on the rotor can excite mechanical resonances, vibration and noise induced will directly impact on service life and operating stability of the motor. In this paper, the radial electromagnetic forces distribution characteristics have been theoretically simulation investigated on the basis of 2D FEM method. Several methods are adopted to reduce the vibration and noise. Furthermore, a noval testing of torque ripple and vibration in a low speed Direct-driven PMSMs was presented to validate the theoretical analysis. The conclusion has a good meaning to practical engineering testing and optimum design of such motors.