Measurement of Vibration and Acoustic Noise Generated by Magnetostriction in Three Stator Cores Made of High Silicon Steel, Amorphous Iron, and Conventional Silicon Steel

The deformation of stators due to radial electro-magnetic forces is considered as the main source of vibration and acoustic noise in electric machines. Similarly, the deformation due to magnetostriction also contributes to the acoustic noise. In this paper, the strain, acceleration, and sound pressure level generated by magnetostriction are measured on three stator cores. The three cores are made of high silicon steel, amorphous iron, and conventional silicon steel. These materials are selected for their significantly different magnetostriction properties. The measurement results indicate that magneto-striction can cause severe vibration and acoustic noise in the stator cores. Additionally, regulating the flux density inside the stator yoke can reduce the magnetostrictive vibration and acoustic noise.