Hybrid Acoustic Model of Electric Vehicles: Force Excitation in Permanent-Magnet Synchronous Machines

In this paper, an integrated model for acoustic evaluation of electric vehicles is introduced. The paper focuses on the force excitation part of the model. The analysis is performed for permanent magnet synchronous machines. The excitation forces are placed on the stator teeth and calculated for a structure dynamic model of the power train. A model for the acoustic emission is adapted, and finally, the psychoacoustical behavior is characterized at the position of the driver of the e-car. An approach for the design of the rotor pole topology is introduced to ensure a beneficial acoustic behavior under consideration of air gap flux density and related force densities on the stator teeth. The calculation is performed using finite-element analysis simulation, but also analytical design methods are considered. Objective of this comparison is a very short computation time and, therefore, an efficient simulation process. The model is validated by measurements on test benches.