Towards low audible noise drives for FEV applications

This paper presents the required steps for the multiphysics acoustic simulation of electrical machines to evaluate its noise behaviour. The proposed scheme is of particular interest for the design and development of electrical drives for full electric vehicles (FEV), because it allows predicting the acoustic characteristic before building a prototype. This numerical approach starts with the electromagnetic force-wave simulation. The computation by a structure dynamic model determines the deformation of the mechanical structure due to the force-waves. The final step of the simulation approach consists of the computation of the excited acoustic radiation. Here, particular attention is paid to the structural-dynamic model. Modelling of microstructures, such as the laminated iron core or insulated coils, is memory and computational expensive. A systematic material homogenisation technique, based on experimental- and numerical modal analyses, yields a higher accuracy at lower computational costs when compared to standard numerical approaches. The presented multiphysics simulation is validated by measurements. The proposed methods are presented by means of a realistic and technically relevant case study.