Experimental Study of a Directly Oil-Cooled Electrical Machine for a Full-Electric Vehicle by Using Low Viscosity Oil


Huihui Xu, Georg Tobias Götz, Shimin Zhang, Rick W. De Docker, 24th European Conference on Power Electronics and Applications, 05.-09. September 2022.



The thermal performance of an integrated electric drive unit, that consists of a directly oil-cooled electrical machine and a transmission, is experimentally studied. The cooling performance using two types of oil with different viscosities is analyzed with the help of empirical formulas and a lumped-parameter thermal model. The resulting thermal model with a single parameter set models the thermal behavior with the two different oil types. This approach allows the separate study of the drive unit and the oil performance with respect to different oil viscosities.