Study on the variation laws of electromagnetic vibration considered the skewed rotor in a squirrel-cage induction motor

Taking a squirrel-cage induction motor Y802-2 as an example, electromagnetic vibration is researched in this paper. Based on the results of transient magnetic fields, electromagnetic forces of the motor are calculated by the Maxwell equations, and electromagnetic forces of points close to the inner diameter of the stator in the air gap are taken as the load condition, and the electromagnetic vibration is researched according to the three-dimensional model of the motor. Curves of vibration displacement of the motor are achieved, and the frequencies and magnitudes of the vibration displacement are calculated utilizing the methods of FFT and spectral analysis. By comparing amplitudes of tooth harmonics corresponding to the frequency under non-skewed and skewed, the influence of skewed slots on electromagnetic vibration is quantitatively analyzed. The radial vibration of the motor is tested by using the acceleration sensor finally, and the conclusion is proved to be correct by experiments. The method of electromagnetic vibration calculated in this paper can also provide a reference for vibration researches. © 2015 Chin. Soc. for Elec. Eng.