Study on Vibration Displacement and Noise for Amorphous Metal Alloy Dry-Type Transformer

Abstract

Power transformers have serious quivering and sound issues. Accordingly, as the origin of sound, it is extremely significant to have precise core vibration controls. Magnetostriction of amorphous metal alloy core remains the principal root of the transformer vibration, and transformer vibration simulation considering magnetostrictive effect has always been a difficult point. Targeting at the problem of excessive noise of amorphous transformers, three-dimensional electromagnetic transient analysis is solved. Mechanical stress and cores displacement are obtained by finite element method (FEM). Taking the core displacement as the excitation of the transformer vibration calculation, and then considering the air-structure interaction of the body-transformer, the vibration and radiated noise of the whole transformer were calculated. Using the established calculation process, the changes of damping strut on transformer brackets with different thickness, as well as the influence of transformer bottom restraint on vibration and noise were analyzed. Experiments are established to analyze the vibration and sound of the transformer cores with different thicknesses of damping strut, and the results display that the sound pressure level and vibration displacement are reduced by utilizing suitable thickness and damping struts on transformer bracket. The simulation and testing values are almost in accordance, which show that the method is reasonable.