Coupled 3-D Thermal and Electromagnetic Modelling of a Liquid-cooled Transverse Flux Traction Motor

Modelling of electrical machines is constantly refined and it is now possible to couple CFD thermal models with FEM electromagnetic models, thereby considering the thermal effects on motor materials. Usually, the models are reduced as much as possible (i.e. 2-D instead of 3-D or using symmetry conditions) in order to reduce calculation time and computer resources. However, in this paper it is shown how to model an interior permanent magnet transverse flux (TF -IPM) motor in 3-D so to be able to include magnet, core and copper loss and the effect of air and liquid cooling. The simulation results are compared with results of a comparably sized liquid-cooled radial flux IPM (RF-IPM) motor. It is shown that the TF-motor cooling is very efficient due to the lack of end-windings.