Grain-Oriented Steel Rings for an Experimental Comparison of Relative Magnetostriction and Maxwell's Forces Effects

The magnetic material quality of transformer cores influences their emitted acoustic noise. The latter is generated by vibrations resulting from the effects of Maxwell's forces, located in the corners, and the magnetostriction inside the magnetic steel. In this paper, two annular structures allow differentiating these two phenomena and analyzing the vibration origins. Then, two different materials are compared, leading to conclusions about the influence of the material anisotropy on vibrations. At last, the measured vibration components are fully justified with the local saturation effects.