Noise radiated by a permanent magnet synchronous motor: Simulation methodology and influence of motor defects

A simulation methodology is described in this paper. It consists in a multi-physical approach to simulate the dynamic forces and noise radiated by electric motors. The principle is first to calculate the excitation due to electromagnetic phenomena using an electromagnetic finite element solver. This excitation is then projected onto the structure mesh of the stator in order to calculate its dynamic response and the radiated sound power. This paper focuses on the possibility to include in this simulation the defects related to a real machine such as static eccentricity or dynamic eccentricity in order to enhance its accuracy. The excitations are analyzed in terms of excitation content (frequency content and spatial distribution) and the consequences on the sound power radiated by the machine are discussed.