Магнитные вибрации сердечника статора магнитоэлектрического вентильного двигателя

Abstract

The radial and tangential tensions causing force effects on the stator core are considered as applied to a 150 kW brushless permanent magnet motor. The orders of tension waves, their displacement velocities, and the frequencies of forced force actions are analyzed. The electromagnetic torques of tangential tensions are investigated. It is shown that with non-sinusoidal excitation of the rotor, same-order higher harmonics of the magnetic induction from the rotor magnets and stator currents cause high-frequency electromagnetic torques. Three resonant frequencies of the stator core at radial magnetic forces are calculated. The stator core radial displacement amplitudes and vibration velocities were determined, which have been found to be close to experimental data. An experimental frequency response of the motor casing noise for its idle operation mode is obtained. Comments regarding the sources of noise bursts occurring at a number of frequencies are given. The influence of insufficiently suppressed high-frequency reactive torque (the "walking" torque) on the motor noise is pointed out. It is shown that the presence of a residual reactive torque with an amplitude measured from experiment leads to a rather high burst of motor casing noise at a frequency of 3500 Hz.