A coupled electromagnetic-mechanical-acoustic model of a DC electric motor
In this article, we present an investigation into the sound radiation from a permanent-magnet DC electric motor using the finite-element (FE) and boundary-element (BE) models. A three-times-coupled electromagnetic-mechanical-acoustic numerical model was set-up to predict the acoustic field. The first stage was to calculate the magnetic forces that excite the structure of the motor by using the FEM. In the second stage, the exciting magnetic forces were applied to the structural model, where the harmonic analysis was carried out using the FEM. The last stage was to model the acoustics by using the BEM. In order to evaluate the numerical model, the computational results were compared with the vibration and acoustic measurements and a reasonable agreement was found.
magnetic forces electrical machines noise boundary element method