Power Electronic (PE) will play an essential role in
future drive concepts. Nowadays, mainly water/glycol-based cooling media are
used to cool PE. Due to their high electrical conductivity (EC), water/glycol-based
coolants cannot be used for direct cooling of the electrical components. Direct
cooling concepts with dedicated transmission fluids show potential usage of fluid
in direct contact with electrified parts. This results in special requirements for
the fluids and materials. The aimed action as a coolant requires a defined measurement
and characterization of fluid properties and heat transfer in order to assess the
cooling ability of a fluid. The purpose of the work was to develop a new measurement
setup based on the thermal transient method with which the thermal requirements
of cooling fluids for a direct cooling concept can be assessed. With this method,
relevant transmission fluids have been tested and the thermal performance compared to indirect cooling effect of water/glycol
is discussed. The result of the work is that the measurement method
is very well suited for the application-related evaluation of the fluids. Direct
oil cooling with transmission fluids could increase heat transfer coefficient by
a factor of 3 to 8, compared to the indirect cooing with water/glycol as cooling
media.
References
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[2]
Griesinger, A. (2019) Wärmemanagement in der Elektronik, Theorie und Praxis, Springer Vieweg. Springer-Verlag GmbH Deutschland, Heidelberg.
https://doi.org/10.1007/978-3-662-58682-2
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Bennion, K. and Moreno, G. (2015) Convective Heat Transfer Coefficients of Automatic Transmission Fluid Jets with Implications for Electric Machine Thermal Management, National Renewable Energy Laboratory. International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems (InterPACK), San Francisco, 6-9 July 2015.
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https://doi.org/10.4271/2019-01-2337
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Maelger, H., Petuchow, A., Plaatje, A., Yungwan K. and Banks A. (2019) Realistic Testing to Assess How Electrified Transmission Fluids Will Withstand Ageing, CTI Symposium. 18th International Congress and Expo, Berlin, 10-11 December 2019.
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Schlünder, E.U. and Gnielinski, V. (1967) Wärme- und Stoffübertragung zwischen Gut und aufprallendem Düsenstrahl. Chemie Ingenieur Technik, 39, 578-584.
https://doi.org/10.1002/cite.330390915
