Prediction of vibration levels and resonant frequencies in static electrical apparatus

Results of computer simulations obtained by a finite-element package, FLUXMECA, are presented and compared with experimental measurements of vibrations of static inductors. The objective is to reduce the vibrations´ level and the acoustic noise of the transformers. Resonant frequencies and the mechanical behavior of the inductors are predicted with a mechanical finite-element model coupled with Maxwell´s equations. A homogenization algorithm allows representation of a stratified structure by a homogenized one. Two kinds of inductors have been tested: cylindrical ones without iron cores and classical iron-cored inductors. A study of the electromagnetic forces and the mechanical structures is presented, clarifying the generation of noise and vibrations in static electrical apparatus.<>