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A Review of the State of the Art of Electric Traction Motors Cooling Techniques
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 03, 2018 by SAE International in United States
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This paper provides a review on state-of-art modern cooling systems employed for thermal cooling of electric motors for vehicle applications. In recent years, the pursue of a more sustainable and ecofriendly mobility has pushed the research towards the development of electric vehicle powertrain systems. Besides the evident advantages of the adoption of electric traction systems in terms of pollution and efficiency, the need of an effective cooling system for the electric machine components gained more and more importance in order to maintain high efficiency and ensure high durability. In fact, it is known that high temperatures can be harmful for the electric motor: besides the evident damages for mechanical parts, the influence on the permanent magnet properties is not negligible  . In this fast-evolving environment, different solutions for the thermal problem have been researched and adopted, each one with its own pros and cons. Those who face the development of a PM machine can found plenty of these solutions in literature; so, the purpose of this paper is to draw a first qualitative comparison among the most important mechanisms available to extract heat from the electric machine and to guide the reader to an efficient and effective solution. Various methodologies for heat extraction are here described: resilient thermal pads for a conductive cooling; forced air and liquid loops, spray cooling and hollow rotor shaft for gases/fluids convective cooling methods. Finally, it is provided a table for a qualitative comparison among the various cases.
|Market Research Report||The Electric Vehicles Report 2011|
|Magazine Issue||Automotive Engineering International 2009-06-01|
|Technical Paper||Advanced Automotive Propulsion Systems - Alternatives, Combinations and Trends|
CitationCarriero, A., Locatelli, M., Ramakrishnan, K., Mastinu, G. et al., "A Review of the State of the Art of Electric Traction Motors Cooling Techniques," SAE Technical Paper 2018-01-0057, 2018, https://doi.org/10.4271/2018-01-0057.
Data Sets - Support Documents
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- Hanselman, D.D., “Brushless Permanent Magnet Motor Design,” 2nd Edition (Cranston, RI, Magna Physics Publishing, 2003), 34-38.
- D.Zarko, “A Systematic Approach to Optimized Design of Permanent Magnet Motors with Reduced Torque Pulsations,” Madison, 2004, DOI: 10.1097/01.chi.0000138358.13852.71.
- A.Ranjbar and B.Fahimi, “AC Machines: Permanent Magnet Synchronous and Induction Machines,” Encyclopedia of Sustainability Science and Technology 17-46, 2012, DOI: 10.1080/08989621.2012.718678.
- Nema (National Electrical Manufacturer Association), “Enclosures for Electrical Equipment (1000 Volts Maximum),” Rosslyn, VA 22209, 2014.
- M.Guilizzoni, La Fisica Tecnica e Il Rasoio Di Ockham, Maggioli Editore, 2010.
- M.Popescu, D.Staton, A.Boglietti and A.Cavagnino, “Modern heat extraction systems for electrical machines - A review”, DOI: 10.1017/S1431927618000089.
- R.Mosciatti and R.Medina, “Apparatus and Method for Dissipating Heat from a Motor”. USA Patent 6201321, March 13 2001.
- Millis, A.F., “Heat Transfer,” 2nd Edition (New Jersey, Prentice-Hall, 1999), doi:10.1016/S0195-5616(99)50111-3.
- J. T.Gierer and K. D.Cox, “Electric Motor Having an Improved Airflow Cooling System”. USA Patent 6011331, January 4 2000.
- D.Denton, J.Lutz, K. R.Lewis, J.Frazzini et al., “Rotor Cooling Apparatus”. USA Patent 2004/0036367, February 26 2004.
- M.Cronin and T. N.Iund, “Cooling System for an Electric Motor”. USA Patent 7009317, March 7 2006.
- J. R.Crowell, M. M.Doctor, W. R.Johnson, T. K.Marker et al., “Liquid Cooled Electric Motor Frame”. USA Patent 5859482, January 12 1999.
- Staton, D., “Multiphysics Analysis of Electric Machines for Traction,” (Pittsburgh, IEEE ECCE, 2014), doi:10.1002/dev.21247.
- Shimizu, H., Okubo, T., Hirano, I. et al., “Development of an Integrated Electrified Powertrain for a Newly Developed Electric Vehicle,” . In: SAE 2013 World Congress & Exhibition. (2013), doi:10.4271/2013-01-1759.
- Merwerth, D.I.J., “The hybrid-synchronous machine of the new BMW ie & i8,” (Munchen, BMW Group, 2014).
- Audi™ AG,Volkswagen Group™, www.audi-technology-portal.com, accessed Nov. 2017.
- S.Birch, “Audi Claims First Production E-Boosting on 2017 SQ7,” SAE Automotive Engineering, March 2016, DOI: 10.1922/CDH_3825Birch05.
- A.Fraser, “In-Wheel Electric Motors, the Packaging and Integration Challenges,” Protean Electric Ltd,2013.
- P.Zhou, N. R.Kalayjian, G. D.Cutler and P. K.Augenbergs, “Liquid Cooled Rotor Assembly,” USA Patent 7579725, 25 August 2009, DOI: 10.1038/nchem.433.
- E.Zysset, “Liquid Cooled Asynchronous Electric Machine,” USA Patent 6191511, February 20 2001, DOI: 10.1016/S0304-3940(01)02175-9.
- P. D.Rawlinson, N. J.Sampson, N. R.Kalayjian and V. G.Johnston, “Thermal Management System for Use with an Integrated Motor Assembly,” USA Patent 2012/0153718, June 21 2012.
- S. H.Swales, P. F.Turnbull, B.Schulze and F. R.Poskie, “Oil Cooled Motor/Generator for an Automotive Powertrain,” USA Patent 8169110, May 1 2012, DOI: 10.1586/erc.12.103.
- J.Raszkowski, E.Kaiser, A.Tata and K.Kinsey, “Method and Apparatus for Cooling a Hybrid Transmission Electric Motor,” USA Patent 7002267, February 21 2006.
- L.Brooke, http://articles.sae.org/13666/, accessed Nov. 2017, DOI: 10.1093/jnci/djx281.
- A.Jaura, C.-W.Park, M.Hammond and S.Thomas, “Cooling System and Method for a Hybrid Electric Vehicle,” USA Patent 2004/0045749 A1, March 11 2004.
- YASA ltd., http://www.yasamotors.com/, accessed Nov. 2017.
- Koenigsegg Automotive AB, http://www.koenigsegg.com/regera/, accessed Nov. 2017.
- Equipmake ltd., http://equipmake.co.uk/, accessed Nov. 2017.
- Kawamura, T. and Atarashi, T.M.H., “High power density motor for racing use,” (Tochigi, 321-3393 Japan, Honda R&D CO. Ltd., Automobile R&D Center, 2011).
- Okuda, K., Yasuda, Y., Adachi, M., and Tabata, A., “Development of Multi Stage Hybrid Transmission,” . In: WCX™ 17: SAE World Congress. (), doi:10.4271/2017-01-1156.
- Burress, T., Campbell, S., Coomer, C., Ayers, C., and Marlino, L., “Evaluation of the 2010 Toyota Prius Hybrid Energy Drive System,” (Oak Ridge, Tennessee 37831, Oak Ridge National Laboratory, 2011).
- Hsu, J., Nelson, S., Jallouk, P., Ayers, C. et al., “Report on Toyota Prius Motor Thermal Management,” (Oak Ridge, Tennessee 37831, Oak Ridge National Laboratory, 2005).
- ZF Friedrichshafen AG™, “ZF’s new 8-Speed Dual Clutch Transmission for Sports Vehicles,” February 2017.
- EVDrive Inc., http://www.evdrive.com/, accessed Nov. 2017.
- Davin, T., Pellè, J., Harmand, S., and Yu, R., “Experimental Study of Oil Cooling System for Electric Motors,” Applied Thermal Engineering Journal 75, 2015, doi:10.1016/j.applthermaleng.2014.10.060.
- Howell, J.R., Siegel, R., and Menguc, M.P., “Thermal Radiation Heat Transfer,” (Boca Raton, FL, Taylor & Francis Group, 2010).