CHARACTERIZATION OF THE AUDIBLE MAGNETIC NOISE EMITTED BY TRACTION MOTORS IN RAILWAY ROLLING STOCK

摘要

This paper first presents the analytical models of an ALSTOM simulation software, DIVA,which computes the vibratory and acoustic behavior of a variable-speed induction machinedue to Maxwell forces. This radial magnetic pressure in the air-gap makes the statorvibrate in the audible range, creating the so-called magnetic noise characterized by a hightonality.On the ground on these analytical models, the main magnetic vibrations due to slotting,pulse-width modulation (PWM) harmonics and their interaction are then analyticallycharacterized. Their number of nodes, velocity and propagation direction areexperimentally validated by visualizing the stator deflection shapes.Finally, some experimental validations of the simulation tool are presented. On the groundof both analytical results and simulations, it is shown that some quieter motors can bedesigned acting on the motor geometry (especially slot numbers) and PWM strategy.