Reluctance Machines Facing the challenges of future electrical power trains Prof E.A. Lomonova Dr J.J.H. Paulides

1. Electromechanics and Power Electronics Group
Eindhoven University of Technology, NL
Phone: + 31 (0)40 247-3573/2310
Fax: + 31 (0)40 243-4364
e’mail: e.lomonova@tue.nl
http://www.tue.nl/epe
Reluctance Machines
Facing the challenges
of future electrical power trains
Prof E.A. Lomonova (e.lomonova@tue.nl)
Dr J.J.H. Paulides (j.j.h.paulides@tue.nl)
… …
and many MSc, PDeng and PhD students

2. Classification of electrical machines
1
1

3. Synchronous reluctance
machines
2
2

4. 3
“Simple” salient IM-based salient structures
structure
Segmental
structure
IPM-based
structure
Double barrier
structure
Some historical developments…
3

5. Modern SynRM structures
4
Axially laminated rotor:
• Very high performance
• Complex construction
• Costly to manufacture
Transversely laminated rotor:
• High performance
• Mass-production by punching possible
• Relatively cheap to manufacture
Promising for
mass-production!
4

6. • Stator voltage equations in dq-reference frame
(no iron losses):
d
v R
i
dt
v
R i
d
• Phasor diagram:
5
sd
sd s sd sq r
sq
sq s sq sd r
dt
−
+
= +
= +
Non-linearity and position dependence:
sd = f(isd,isq,
r) and
sq = f(isd,isq,
r)
Analytical modeling
5

7. Numerical modeling: Finite Element (FE)
Properties of FE modeling:
• Accurate magnetic field solution
• Includes non-linear soft-magnetic materials
• Includes leakage flux of mechanical connections
• Relatively long computation time
6
6

8. Drives and control
Structure of the SynRM drive:
7
7

9. Examples of commercial SynRM drives
ABB SynRM motor-drive package:
• Power range: 11 kW – 315 kW
• High efficiency (IE4) or high power
density
• Seperate drive with sensorless
control
8
KSB SuPremE® motor
• Power range: 0.55 kW – 45 kW
• High efficiency (IE4)
• Motor mounted drive with sensorless
control
8

10. Permanent magnet assisted SynRMs
Improving SynRM performance:
• Add cheap PM to barriers
(e.g. Ferrite PMs)
• Increase torque capability
and power factor
9
9

11. Flux-switching machines
10

12. • Switched reluctance machines with assisted excitation
• Flux-switching machines
11
Reluctance machines with hybrid excitation

13. Switched reluctance machine
=
Low torque
density
+ Robust
rotor
structure
Flux-switching machine
Permanent
magnets
Three-phase
armature
windings
Ferromagnetic
material
Brushless AC/DC machine
Complicated
rotor structure
High
torque
density
12
Flux switching machine

14. • With PM Excitation
• With DC Excitation
13
PM or DC excitation?

15. • Advantages of DC excitation:
• No need of rare-earth elements
• Allow higher temperature
• Wide speed range[*]
[*] Y. Tang, J. J. H. Paulides, E. A. Lomonova, Flux-switching
machine with DC excitation, Transaction on
Magnetics, Vol. 48(11), pp. 3583-3586, Nov., 2012
14
DC excited flux-switching machine

16. Toroidal DC winding
Lap DC winding
AC windings
Concentrated
windings
Distributed windings
DC windings
15
Different winding topologies

17. Flux-switching machines
Applications
16

18. • Automotive industry • Energy
In-wheel traction of
electric car
• Servo drives
Wind
Milling
Cutters Hydro
17
Application of flux switching machines

19. 18
Application – In-wheel traction
• Automotive industry
In-wheel traction of
electric car

20. CPSR
Torque Max.
Torque
Base
speed
Power
Max.
Constant power speed
• Compact and light-weight
• High torque density
• Wide speed range
• High efficiency
Speed
• Requirements for the motor design
19
Application – In-wheel traction

21. •

22. •
• inverter supply voltage
• !#$,
%# #$
50 km/h@15%
140 km/h@0%
80 km/h@10%
20
Efficiency map based on:
• Copper losses Pcu,
• Iron losses Pfe, and
• Friction losses.
Application example: Traction

23. • Field oriented control (FOC)
• Controller structure
• Control of '

24. () * and +
• Field weakening
• Space vector modulation
21
Application example: Traction controller

25. • Chosen control strategy
• Follow the ,-./ line
• Calculate
-./)01

26. 2*
• Calculate 3453)
-./

27. 456*
• 6 follows 3
• Always on the ,-./ line
789:8
:
;
= ?8)78*7@
22
Application example: Control strategy

28. 23
Application of flux switching machines
• Servo drives
Cutters Milling

29. Application example – Design for fast acceleration
9-10-2014 PAGE 24
Back-emf
Torque
24

30. Application example – Performance comparison
• Stall torques measured from the normalized de-rating
characteristics at a housing temperature of 60°C
Benchmark Prototype
• Torque ripple reduced by a continuous rotor skewing
25
• The FSPM prototype is compared to a state-of-the-art industrial
benchmark machine, i.e. a brushless PM motor.

31. 26
Application example – Performance evaluation
• FSPMs offer very good servo capability with lowered
inertia due to PM-less rotor with a high stall torque
• A higher torque-to-inertia ratio is achieved for an active
motor volume under identical thermal operation
• A smooth torque profile combined with low noise is
ensured with only 0.2% ripple
Electromechanics and Power Electronics Group
Eindhoven University of Technology, NL
Phone: + 31 (0)40 247-3573/2310
Fax: + 31 (0)40 243-4364
e’mail: e.lomonova@tue.nl
http://www.tue.nl/epe

32. Further reading
TU/e EPE Literature
27
Electromechanics and Power Electronics Group
Eindhoven University of Technology, NL
Phone: + 31 (0)40 247-3573/2310
Fax: + 31 (0)40 243-4364
e’mail: e.lomonova@tue.nl
http://www.tue.nl/epe

33. 20+ publications in peer reviewed international journals
• IEEE Magnetics, Industry applications, Power electronics…
• COMPEL, ETASR, IET, Springer, Elsevier…
30+ publications in highly ranked European and international
conferences:
• INTERMAG
• EVER
• ELECTRIMACS
• COMPUMAG
• ICEM
• ECCE
28
Publications Conferences (Overview)
...

34. • Journal publications
• Y. Tang, J. J. H. Paulides, E. A. Lomonova, “Energy conversion in dc excited flux-switching machines”, IEEE
Transactions on Magnetics, to be published in 2014.
• Y. Tang, J. J. H. Paulides, E. A. Lomonova, “Automated design of dc-excited flux-switching in-wheel motor
using magnetic equivalent circuits”, IEEE Transactions on Magnetics, to be published in 2014.
• Y. Tang, J. J. H. Paulides, E. A. Lomonova, “Topologies of flux-switching machines for in-wheel traction”,
COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic
Engineering, to be published in 2014.
• Y. Tang, J. J. H. Paulides, E. A. Lomonova, “Analytical modeling of flux-switching motor using variable
magnetic equivalent circuits”, ISRN Automotive Engineering, 2014, 1-11.
• Y. Tang, T. E. Motoasca, J. J. H. Paulides, E. A. Lomonova, “Comparison of flux-switching machines and
permanent magnet synchronous machines in an in-wheel traction application”, COMPEL: The International
Journal for Computation and Mathematics in Electrical and Electronic Engineering, 32(1),153 – 165, 2013.
• Y. Tang, J. J. H. Paulides, T. E. Motoasca, E. A. Lomonova, “Flux-switching machine with DC excitation”, IEEE
Transactions on Magnetics, 48(11), 3583-3586, 2012.
• Y. Tang, J. J. H. Paulides, K. V. Kazmin, E. A. Lomonova, “Investigation of winding topologies for permanent
magnet in-wheel motors”, COMPEL: The International Journal for Computation and Mathematics in Electrical
and Electronic Engineering, 31(1), 88-107, 2012.
• J. J. H. Paulides, B. L. J. Gysen, K. J. Meessen, Y. Tang, E. A. Lomonova, ”Influence of multiple air gaps on the
performance of electrical machines with (semi) Halbach magnetization”, IEEE Transactions on Magnetics,
47(10), 2664-2667, 2011.
• E. A. Lomonova, E. V. Kazmin, E.V., Y. Tang, J. J. H. Paulides, “In-wheel PM motor : compromise between high
power density and extended speed capability”, COMPEL: The International Journal for Computation and
Mathematics in Electrical and Electronic Engineering, 30(1), 98-116, 2011
29
Publications Conferences (cont…)

35. • Journal publications
• Sprangers, R.L.J., Paulides, J.J.H., Boynov, K., Waarma, J. and Lomonova, E.A., ‘Comparison of two
anisotropic layer models applied to induction motors’, IEEE Trans. Ind. Appl., Vol. 50, No. 4, pp. 2533-2543,
July/August 2014
• Ilhan, E., Kremers, M.F.J., Motoasca, T.E., Paulides, J.J.H. Lomonova, E. (2013). Nonlinear performance
characteristics of flux-switching PM motors. Journal of Electrical Engineering, 2013:593434
• Kremers, M.F.J., Paulides, J.J.H., Ilhan, E., Janssen, J.L.G. Lomonova, E. (2013). Relative permeability in a
3D analytical surface charge model of permanent magnets. IEEE Transactions on Magnetics, 49(5), 2299-2302.
• Ilhan, E., Paulides, J.J.H. Lomonova, E. (2012). Fast torque estimation of in-wheel parallel flux switching
machines for hybrid trucks. COMPEL: The International Journal for Computation and Mathematics in
Electrical and Electronic Engineering, 31(1), 40-53.
• Ilhan, E., Motoasca, T.E., Paulides, J.J.H. Lomonova, E. (2012). Conformal mapping: Schwarz-Christoffel
method for flux-switching PM machines. Journal of Mathematical Sciences, 6:37
• Ilhan, E., Kremers, M.F.J., Motoasca, T.E., Paulides, J.J.H. Lomonova, E. (2012). Spatial discretization
methods for air gap permeance calculations in double salient traction motors. IEEE Transactions on Industry
Applications, 48(6), 2165-2172. 2010
• Gysen, B.L.J., Ilhan, E., Meessen, K.J., Paulides, J.J.H. Lomonova, E. (2010). Modeling of flux switching
permanent magnet machines with Fourier Analysis. IEEE Transactions on Magnetics, 46(6), 1499-1502.
• Ilhan, E., Paulides, J.J.H. Lomonova, E. (2010). Fast torque estimation of in-wheel parallel flux switching
machines for hybrid trucks. Journal of Electrical Engineering, 10(3), 175-182.
• Ilhan, E., Gysen, B.L.J., Paulides, J.J.H. Lomonova, E. (2010). Analytical hybrid model for flux switching
permanent magnet machines. IEEE Transactions on Magnetics, 46(6), 1762-1765.
• Ilhan, E., Motoasca, T.E., Paulides, J.J.H. Lomonova, E. (2012). Energy conversion loops for flux-switching
PM machine analysis. Engineering, Technology Applied Science Research, 2(5), 285-290.
30
Publications Conferences (cont…)

36. • Conference publications
• Y. Tang, J. J. H. Paulides, E. A. Lomonova, “Energy conversion in dc excited flux-switching machines”,
Proceedings of the IEEE International Magnetics Conference, (INTERMAG 2014), Dresden, Germany, May 4-8,
2014.
• Y. Tang, J. J. H. Paulides, E. A. Lomonova, “Automated design of dc-excited flux-switching in-wheel motor
using magnetic equivalent circuits”, Proceedings of the 2014 9th International Conference on Ecological
Vehicles and Renewable Energies (EVER), Monaco, 26-27 March 2014.
• Y. Tang, J. J. H. Paulides, I. J. M. Besselink, J. R. Gardner, E. A. Lomonova, “Indirect drive in-wheel system for
HEV/EV traction”. Proceedings of the 27th International Electric Vehicle Symposium Exhibition (EVS27),
Barcelona, Spain, 17-20 November 2013.
• Y. Tang, J. J. H. Paulides, E. A. Lomonova. Design considerations of flux-switching machines with permanent
magnet or dc excitation. Proceedings of the 2013 15th European Conference on Power Electronics and
Applications (EPE), Lille, France, 3-5 September 2013.
• Y. Tang, J. J. H. Paulides, E. A. Lomonova, “Topologies of flux-switching machines for in-wheel traction”,
Proceedings Ecological Vehicles and Renewable Energies (EVER 2013), Monaco, 27 – 30 March, 2013.
• Y. Tang, T. E. Motoasca, J. J. H. Paulides, E. A. Lomonova, “Analytical modeling of flux-switching machines
using variable global reluctance networks”, Proceedings of the 20th International conference on Electrical
machines (ICEM), pp. 2792 – 2789, 2-5 Sept., 2012.
• Y. Tang, J. J. H. Paulides, T. E. Motoasca, E. A. Lomonova, “Flux-switching machine with DC excitation”,
Proceedings of the IEEE International Magnetics Conference (INTERMAG 2012), Vancouver, Canada, 7-11 May
2012.
• Y. Tang, T. E. Motoasca, J. J. H. Paulides, E. A. Lomonova, “Investigation of winding topologies for flux
switching machines”, Proceedings of the 15th International Symposium on Electromagnetic Fields in
Mechatronics, Electrical and Electronic Engineering (ISEF-2011) Funchal, Madeira, 1-3 September 2011.
31
Publications Conferences (cont…)

37. • Conference publications
• Y. Tang, J. L. Duarte, R. P. P. Smeets, T. E. Motoasca, E. A. Lomonova, “Multi-stage DC hybrid switch with slow
switching”, Proceedings of the 37th Annual Conference of the IEEE Industrial Electronics Society (IECON
2011), pp. 1462-1467, Melbourne, VIC 7-11 November 2011.
• Y. Tang, T. E. Motoasca, J. J. H. Paulides, E. A. Lomonova, “Comparison of flux-switching machines and
permanent magnet synchronous machines in an in-wheel traction application”, Proceedings Ecological
Vehicles and Renewable Energies (EVER 2011), Monaco, pp. 1-10, 30 March - 3 April 2011.
• Y. Tang, J. J. H. Paulides, E. V. Kazmin, E. A. Lomonova, “Investigation of winding topologies for permanent
magnet in-wheel motors”, Proceedings Ecological Vehicles and Renewable Energies (EVER 2010), pp. 1-14,
Monaco, 25-28 March 2010.
• Sprangers, R.L.J., Motoasca, T.E. and Lomonova, E.A., ‘Development of an expert system for three-phase
induction motors’, YRS 2012, Delft, The Netherlands
• Sprangers, R.L.J., Motoasca, T.E. and Lomonova, E.A., ‘Extended anisotropic layer theory for electrical
machines, CEFC 2012, Oita, Japan
• Sprangers, R.L.J., Paulides, J.J.H., Boynov, K., Waarma, J. and Lomonova, E.A., ‘Design and optimization
tools for high-efficiency three-phase induction motors’, EPE’13 ECCE Europe, Lille, France
• Sprangers, R.L.J., Paulides, J.J.H., Boynov, K., Waarma, J. and Lomonova, E.A., ‘Comparison of two
anisotropic layer models applied to induction motors’, IEMDC 2013, Chicago, USA
• Sprangers, R.L.J., Gysen, B.L.J., Paulides, J.J.H., Waarma, J. and Lomonova, E.A., ‘A fast semi-analytical
model for the slotted structure of induction motors with 36/28 stator/rotor slot combination’, Electrimacs
2014, Valencia, Spain
• Sprangers, R.L.J., Gysen, B.L.J., Paulides, J.J.H., Waarma, J. and Lomonova, E.A., ‘Calculation of induced
rotor current in induction motors using a slotted semi-analytical harmonic model’, ICEM 2014, Berlin,Germany
32
Publications Conferences (cont…)

38. • Conference publications
• Sprangers, R.L.J., Gysen, B.L.J., Paulides, J.J.H., Waarma, J. and Lomonova, E.A., ‘Electric circuit coupling of
a slotted semi-analytical model for induction motors based on harmonic modeling’, ECCE 2014, Pittsburgh
• Ilhan, E., Kremers, M.F.J., Motoasca, T.E., Paulides, J.J.H. Lomonova, E. (2013). Transient thermal analysis of
flux switching PM machines. Oral : Paper presented at Proceedings of the 2013 8th International Conference and
Exhibition on Ecological Vehicles and Renewable Energies (EVER), 27-30 March 2013, Monte Carlo, Monaco, (pp.
1-7). Piscataway: IEEE Service Center.2012
• Ilhan, E., Kremers, M.F.J., Motoasca, T.E., Paulides, J.J.H. Lomonova, E. (2012). Sensitivity analysis for phase
inductances in Flux-switching PM machine. Proceedings paper : Proceedings of the 20th International
Conference on Electrical Machines (ICEM 2012), September 2-5 2012, Marseille, France, (pp. 763-768). Piscataway:
IEEE Service Center.
• Ilhan, E., Motoasca, T.E., Paulides, J.J.H. Lomonova, E. (2012). Nonlinear performance characteristic of Flux
switching PM motors. Proceedings paper : Proceedings of IEEE International Magnetics Conference (INTERMAG),
May 7-11 2012, Vancouver, (pp. 1-1).
• Kremers, M.F.J., Paulides, J.J.H., Ilhan, E., Janssen, J.L.G. Lomonova, E. (2012). Relative permeability in a 3D
analytical surface charge model of permanent magnets. Poster presented at Proceedings of the Fifteenth Biennial
IEEE Conference on Electromagnetic Field Computation (CEFC 2012), November 11-14, 2012, Oita, Japan, (pp.
194). Piscataway: IEEE Service Center.
• Kremers, M.F.J., Paulides, J.J.H., Ilhan, E., Janssen, J.L.G. Lomonova, E. (2012). Analytical field calculations of
skewed magnets. Poster presented at Proceedings of the the Fifteenth Biennial IEEE Conference on
Electromagnetic Field Computation (CEFC 2012), November 11-14, 2012, Oita, Japan, (pp. 195). Piscataway: IEEE.
33
Publications Conferences (cont…)

39. • Conference publications
• Kremers, M.F.J., Paulides, J.J.H., Ilhan, E., Janssen, J.L.G. Lomonova, E. (2012). Design guidelines for coreless
linear actuators. Poster presented at Proceedings of the Fifteenth Biennial IEEE Conference on Electromagnetic
Field Computation (CEFC 2012), November 11-14, 2012, Oita, Japan, (pp. 196). Piscataway: IEEE Service Center.
• Ilhan, E., Motoasca, T.E., Paulides, J.J.H. Lomonova, E. (2011). Conformal mapping: Schwarz-Christoffel
method for flux switching PM machines. Proceedings paper : Proceedings of Computational Magnetics
(COMPUMAG) 12-15 July 2011, Sydney, Australia, (pp. 1-4). COMPUMAG.
• Ilhan, E., Motoasca, T.E., Paulides, J.J.H. Lomonova, E. (2011). Energy conversion loops for flux-switching PM
machine analysis. Proceedings of the XV International Symposium on Electromagnetic Fields in Mechatronics,
Electrical and Electronic Engineering (ISEF 2011), 1-3 September 2011, Funchal, Madeira, (pp. 1-8). ISEF.
• Gysen, B.L.J., Ilhan, E., Meessen, K.J., Paulides, J.J.H. Lomonova, E. (2010). Modeling of flux switching
permanent magnet machines with Fourier analysis. Proceedings of the 11th Joint MMM-Intermag Conference,
January 18-22, 2010, Washington D.C., (pp. 741-741). Piscataway: IEEE.
• Ilhan, E., Paulides, J.J.H., Encica, L. Lomonova, E. (2010). Tooth contour method implementation for the Flux
switching PM Machines. Proceedings of the 19th International Conference on Electrical Machines (ICEM 2010),
September 6-8, 2010, Rome, Italy, (pp. RF-010294-1/6). Piscataway: IEEE.
• Ilhan, E., Gysen, B.L.J., Paulides, J.J.H. Lomonova, E. (2010). Analytical hybrid Flux switching permanent
magnet machines model. Proceedings of the 11th Joint MMM-Intermag Conference, January 18-22, 2010,
Washington D.C., (pp. 1625-1625). Piscataway: IEEE.
• Ilhan, E., Paulides, J.J.H. Lomonova, E. (2010). Fast torque estimation of in-wheel parallel flux switching
machines. Proceedings of the 5th EVER Conference, 25-28 March, Monaco, (pp. 1-7). EVER.
• Ilhan, E., Gysen, B.L.J., Paulides, J.J.H. Lomonova, E. (2010). Analytical hybrid model for flux switching
permanent magnet machines. Proceedings 5th IEEE, Young Researchers Symposium, 29-30-03, 2010, Leuven. ..
.
34
Publications Conferences (cont…)