Transient Thermal Modeling of an Axial Flux Permanent Magnet (AFPM) Machine Using a Hybrid Thermal Model
This paper presents the development of a hybrid
thermal model for the EVO Electric AFM 140 Axial Flux Permanent
Magnet (AFPM) machine as used in hybrid and electric vehicles. The
adopted approach is based on a hybrid lumped parameter and finite
difference method. The proposed method divides each motor
component into regular elements which are connected together in a
thermal resistance network representing all the physical connections
in all three dimensions. The element shape and size are chosen
according to the component geometry to ensure consistency. The
fluid domain is lumped into one region with averaged heat transfer
parameters connecting it to the solid domain. Some model parameters
are obtained from Computation Fluid Dynamic (CFD) simulation and
empirical data. The hybrid thermal model is described by a set of
coupled linear first order differential equations which is discretised
and solved iteratively to obtain the temperature profile. The
computation involved is low and thus the model is suitable for
transient temperature predictions. The maximum error in temperature
prediction is 3.4% and the mean error is consistently lower than the
mean error due to uncertainty in measurements. The details of the
model development, temperature predictions and suggestions for
design improvements are presented in this paper.
[1] K. Sitapati and R. Krishnan, "Performance comparisons of radial and
axial field, permanent-magnet, brushless machines," IEEE Transactions
on Industry Applications, vol. 37, 2001, pp. 1219-1226.
[2] M.U. Lamperth, a Beaudet, and M. Jaensch, "Disc motors for
automotive applications," Hybrid & Eco Friendly Vehicles Conference
2008 (HEVC 2008), 2008, pp. 10-10.
[3] H. Auinger, "Efficiency of electric motors under practical conditions,"
Power Engineering Journal, vol. 15, 2001, p. 163.
[4] J.F. Gieras, Axial Flux Permanent Magnet Brushless Machines, 2008.
[5] S. Scowby, "Thermal modelling of an axial flux permanent magnet
machine," Applied Thermal Engineering, vol. 24, Feb. 2004, pp. 193-
207.
[6] T. Sebastian, "Temperature effects on torque production and efficiency
of PM motors using NdFeB magnets," IEEE Transactions on Industry
Applications, vol. 31, 1995, pp. 353-357.
[7] A. Boglietti, A. Cavagnino, D. Staton, M. Shanel, M. Mueller, and C.
Mejuto, "Evolution and Modern Approaches for Thermal Analysis of
Electrical Machines," IEEE Transactions on Industrial Electronics, vol.
56, Mar. 2009, pp. 871-882.
[8] D. Staton, a Boglietti, and a Cavagnino, "Solving the More Difficult
Aspects of Electric Motor Thermal Analysis in Small and Medium Size
Industrial Induction Motors," IEEE Transactions on Energy
Conversion, vol. 20, Sep. 2005, pp. 620-628.
[9] P.H. Mellor, D. Roberts, and D.R. Turner, "Lumped parameter thermal
model for electrical machines of TEFC design," IEE Proceedings B
Electric Power Applications, vol. 138, 1991, p. 205.
[10] C.H. Lim, G. Airoldi, J.R. Bumby, R.G. Dominy, G.I. Ingram, K.
Mahkamov, N.L. Brown, a Mebarki, and M. Shanel, "Experimental and
CFD investigation of a lumped parameter thermal model of a singlesided,
slotted axial flux generator," International Journal of Thermal
Sciences, vol. 49, Sep. 2010, pp. 1732-1741.
[11] E. Odvárka, N.L. Brown, A. Mebarki, M. Shanel, S. Narayanan, and C.
Ondrusek, "Thermal modelling of water-cooled axial-flux permanent
magnet machine," 5th IET International Conference on Power
Electronics, Machines and Drives (PEMD 2010), 2010, pp. 1-5.
[12] M. Tari, K. Yoshida, S. Sekito, J. Allison, R. Brutsch, a Lutz, and N.
Frost, "A high voltage insulating system with increased thermal
conductivity for turbo generators," Proceedings: Electrical Insulation
Conference and Electrical Manufacturing and Coil Winding
Technology Conference (Cat. No.03CH37480), 2001, pp. 613-617.
[13] E. Serre, P. Bontoux, and B. Launder, "Transitional-turbulent flow with
heat transfer in a closed rotor-stator cavity," Journal of Turbulence, vol.
5, Feb. 2004.
[14] D. a Howey, a S. Holmes, and K.R. Pullen, "Radially resolved
measurement of stator heat transfer in a rotor-stator disc system,"
International Journal of Heat and Mass Transfer, vol. 53, Jan. 2010, pp.
491-501.
[15] D.P. DeWitt, Fundamentals of heat and mass transfer, 1996.
[16] J. Nerg, M. Rilla, and J. Pyrhonen, "Thermal Analysis of Radial-Flux
Electrical Machines With a High Power Density," IEEE Transactions
on Industrial Electronics, vol. 55, Oct. 2008, pp. 3543-3554.
[1] K. Sitapati and R. Krishnan, "Performance comparisons of radial and
axial field, permanent-magnet, brushless machines," IEEE Transactions
on Industry Applications, vol. 37, 2001, pp. 1219-1226.
[2] M.U. Lamperth, a Beaudet, and M. Jaensch, "Disc motors for
automotive applications," Hybrid & Eco Friendly Vehicles Conference
2008 (HEVC 2008), 2008, pp. 10-10.
[3] H. Auinger, "Efficiency of electric motors under practical conditions,"
Power Engineering Journal, vol. 15, 2001, p. 163.
[4] J.F. Gieras, Axial Flux Permanent Magnet Brushless Machines, 2008.
[5] S. Scowby, "Thermal modelling of an axial flux permanent magnet
machine," Applied Thermal Engineering, vol. 24, Feb. 2004, pp. 193-
207.
[6] T. Sebastian, "Temperature effects on torque production and efficiency
of PM motors using NdFeB magnets," IEEE Transactions on Industry
Applications, vol. 31, 1995, pp. 353-357.
[7] A. Boglietti, A. Cavagnino, D. Staton, M. Shanel, M. Mueller, and C.
Mejuto, "Evolution and Modern Approaches for Thermal Analysis of
Electrical Machines," IEEE Transactions on Industrial Electronics, vol.
56, Mar. 2009, pp. 871-882.
[8] D. Staton, a Boglietti, and a Cavagnino, "Solving the More Difficult
Aspects of Electric Motor Thermal Analysis in Small and Medium Size
Industrial Induction Motors," IEEE Transactions on Energy
Conversion, vol. 20, Sep. 2005, pp. 620-628.
[9] P.H. Mellor, D. Roberts, and D.R. Turner, "Lumped parameter thermal
model for electrical machines of TEFC design," IEE Proceedings B
Electric Power Applications, vol. 138, 1991, p. 205.
[10] C.H. Lim, G. Airoldi, J.R. Bumby, R.G. Dominy, G.I. Ingram, K.
Mahkamov, N.L. Brown, a Mebarki, and M. Shanel, "Experimental and
CFD investigation of a lumped parameter thermal model of a singlesided,
slotted axial flux generator," International Journal of Thermal
Sciences, vol. 49, Sep. 2010, pp. 1732-1741.
[11] E. Odvárka, N.L. Brown, A. Mebarki, M. Shanel, S. Narayanan, and C.
Ondrusek, "Thermal modelling of water-cooled axial-flux permanent
magnet machine," 5th IET International Conference on Power
Electronics, Machines and Drives (PEMD 2010), 2010, pp. 1-5.
[12] M. Tari, K. Yoshida, S. Sekito, J. Allison, R. Brutsch, a Lutz, and N.
Frost, "A high voltage insulating system with increased thermal
conductivity for turbo generators," Proceedings: Electrical Insulation
Conference and Electrical Manufacturing and Coil Winding
Technology Conference (Cat. No.03CH37480), 2001, pp. 613-617.
[13] E. Serre, P. Bontoux, and B. Launder, "Transitional-turbulent flow with
heat transfer in a closed rotor-stator cavity," Journal of Turbulence, vol.
5, Feb. 2004.
[14] D. a Howey, a S. Holmes, and K.R. Pullen, "Radially resolved
measurement of stator heat transfer in a rotor-stator disc system,"
International Journal of Heat and Mass Transfer, vol. 53, Jan. 2010, pp.
491-501.
[15] D.P. DeWitt, Fundamentals of heat and mass transfer, 1996.
[16] J. Nerg, M. Rilla, and J. Pyrhonen, "Thermal Analysis of Radial-Flux
Electrical Machines With a High Power Density," IEEE Transactions
on Industrial Electronics, vol. 55, Oct. 2008, pp. 3543-3554.
@article{"International Journal of Mechanical, Industrial and Aerospace Sciences:57298", author = "J. Hey and D. A. Howey and R. Martinez-Botas and M. Lamperth", title = "Transient Thermal Modeling of an Axial Flux Permanent Magnet (AFPM) Machine Using a Hybrid Thermal Model", abstract = "This paper presents the development of a hybrid
thermal model for the EVO Electric AFM 140 Axial Flux Permanent
Magnet (AFPM) machine as used in hybrid and electric vehicles. The
adopted approach is based on a hybrid lumped parameter and finite
difference method. The proposed method divides each motor
component into regular elements which are connected together in a
thermal resistance network representing all the physical connections
in all three dimensions. The element shape and size are chosen
according to the component geometry to ensure consistency. The
fluid domain is lumped into one region with averaged heat transfer
parameters connecting it to the solid domain. Some model parameters
are obtained from Computation Fluid Dynamic (CFD) simulation and
empirical data. The hybrid thermal model is described by a set of
coupled linear first order differential equations which is discretised
and solved iteratively to obtain the temperature profile. The
computation involved is low and thus the model is suitable for
transient temperature predictions. The maximum error in temperature
prediction is 3.4% and the mean error is consistently lower than the
mean error due to uncertainty in measurements. The details of the
model development, temperature predictions and suggestions for
design improvements are presented in this paper.", keywords = "Electric vehicle, hybrid thermal model, transient
temperature prediction, Axial Flux Permanent Magnet machine.", volume = "4", number = "11", pages = "1241-10", }