Permanent Magnet Machines for HighSpeed Applications
Abstract
:1. Introduction
2. SinglePhase and ThreePhase PM Machines
2.1. SinglePhase
2.2. ThreePhase
2.3. Summary
3. Stator Structures and Winding Configurations
3.1. Stator Structure
3.1.1. Slotted
6slot/4pole
6slot/2pole
3slot/2pole
Optimal Design of Slotted Machines
3.1.2. Slotless
3.1.3. Summary of Stator Structures
3.2. Winding Configuration
3.2.1. Overlapping Winding
Slotted Machine
Slotless Machine
3.2.2. NonOverlapping Winding
Slotted Machine
Slotless Machine
3.2.3. Summary of Winding Configurations
 For highpower multislot HSPM machines, overlapping winding and toroidal nonoverlapping winding are employed. The main difference between two winding configurations is the endwinding axial length;
 For lowpower minimalslot HSPM machines, the concentrated nonoverlapping winding is a dominant winding configuration due to short endwinding axial length. Although it has a short endwinding axial length, the toroidal winding needs additional volume radially for the outside windings. These also produce eddy current losses in the frame.
 For slotless HSPM machines, both overlapping and nonoverlapping windings are employed. Fullpitched overlapping windings with the largest winding factor can offer the maximum output torque; however, they have the longest endwinding axial length, while the shortpitched overlapping winding with a relatively small winding factor not only decreases the rotor losses but also improves the rotor mechanical stiffness.
 The toroidal nonoverlapping winding with short endwinding axial length and the simple winding process is popular for slotless stator applications.
 The skewed slotless winding, i.e., helical, rhombic, and diamond windings, with compact structure, selfsupport construction, and no endwinding, is an attractive solution for slotless HSPM machines. However, the nonidealized skewed current direction leads to undesirable torque and force. In addition, the skewed slotless winding needs a 3D model to analyse and requires a special manufacturing process.
4. Rotor Structure
4.1. IPM
4.2. SPM
4.2.1. Sleeve Design
4.2.2. Pole Arc to Pole Pitch
4.3. Solid PM
4.3.1. Solid PM with Sleeve
4.3.2. Solid PM with Hollow Shaft
4.4. Summary
5. Parasitic Effect
5.1. Stator Iron Loss
5.2. AC Copper Loss
5.3. Rotor Eddy Current Loss
5.4. Windage Loss
5.5. Rotor Dynamic and Vibration
5.6. Thermal Aspect
6. Conclusions
Author Contributions
Funding
Conflicts of Interest
Appendix A
Reference  Power (kW)  Speed (krpm)  Slot/Pole  Winding  Rotor  Application 

[30]  2000  20  48s/8p  Overlapping (Fullpitched)  SPM   
[120]  1120  18  27s/4p  Overlapping (Fullpitched)  SPM  Pump Drive 
[46]  1120  18  27s/4p  Overlapping (Fullpitched)  SPM  Compressor 
[146]  800  2.5  24s/4p  Overlapping (Fullpitched)  SPM  Prototype 
[48]  400  10  48s/4p  Overlapping (Fullpitched)  SPM  Prototype 
[147]  300  13.3  12s/14p  Concentrated  IPM  Aircraft Gas Turbine 
[119]  200  40  24s/2p  Overlapping (Fullpitched)  SPM   
[148]  150  24  24s/2p  Toroidal  Solid PM  Turbo Blowers 
[32]  150  17  36s/4p  Overlapping (Fullpitched)  SPM  Prototype 
[84]  140  24  24s/4p  Overlapping (Fullpitched)  SPM/SpokeIPM   
[149]  124  36  24s/2p  Overlapping (Fullpitched)  SPM  Generator 
[114]  117  60  36s/2p  Toroidal  SPM  Micro Gas Turbine 
[34]  117  60  36s/2p  Toroidal  Solid PM  Prototype 
[28]  100  500  Slotless/2p  Toroidal  Solid PM  Mesoscale Gas Turbines 
[33]  100  50  36s/4p  Overlapping (Fullpitched)  SPM  Turbo Generator 
[85]  100  32  24s/4p  Overlapping (Fullpitched)  SPM  Centrifugal Air Blower 
[150]  82  12.5  24s/2p  Overlapping (Fullpitched)  SPM  Centrifugal Pump 
[35]  75  36  24s/2p  Toroidal  Solid PM  Prototype 
[123]  57  30  6s/4p  Concentrated  SPM/InsetPM  Pumps, Compressors, Blower 
[110]  50  100  Slotless/2p  Concentrated/Toroidal/Skewed  Solid PM   
[42]  50  70  12s/2p  Overlapping (Fullpitched)  SPM  Centrifugal TurboCompressors 
[87]  40  40  36s/4p  Overlapping (Fullpitched)  SPM  Prototype 
[115]  40  30  18s/2p  Overlapping (Fullpitched)  SPM  Light Duty Electric Vehicle 
[38]  30  96  18s/2p  Overlapping (Fullpitched)  SPM  Prototype 
[88]  30  20  36s/6p  Overlapping (5/6 shortpitched)  IPM  Compressor 
[39]  25  30  18s/2p  Overlapping (Fullpitched)  SPM  Prototype 
[121]  22  120  6s/2p  Concentrated  SPM  Prototype 
[40]  20  26  18s/2p  Overlapping (Fullpitched)  SPM  Electric Vehicle 
[125]  15.7  125  12s/2p  Overlapping (Fullpitched)  IPM  Prototypes 
[63]  15  150  6s/2p  Concentrated  SPM  EAT 
[63]  15  150  Slotless/2p  Toroidal  SPM  EAT 
[43]  15  120  12S/2P  Overlapping (5/6 shortpitched)  Solid PM  Air Blower 
[36]  15  30  24s/2p  Toroidal  Solid PM  Prototype 
[151]  15  120  12s/2p  Toroidal  Solid PM/SPM  Gas Compressor 
[47]  11.8  15  36s/4p  Overlapping (Fullpitched)  IPM   
[112]  11  50  36s/2p  Overlapping (Fullpitched)  IPM  Spindle Machine Tool 
[61]  11  31.2  6s/2p  Concentrated  Solid PM  Generator 
[41]  10  70  18s/2p  Overlapping (Fullpitched)  SPM  Electricturbo 
[116]  10  70  12s/2p  Overlapping (Fullpitched)  SPM  Prototype 
[89]  7.5  30  24s/2p  Overlapping (4/6 shortpitched)  SPM   
[91]  5  240  6s/2p  Concentrated  SPM   
[24]  5  240  6s/2p  Concentrated  SPM  Electrical Drive System 
[64]  4  150  6s/2p  Concentrated  SPM  Electric Turbocharger 
[50]  4  75  6s/4p  Concentrated  SPM   
[50]  4  75  Slotless/2p  Toroidal  SPM   
[98]  3.7  240  Slotless/2p  Toroidal  SPM  Gasturbine Generator 
[61]  3.5  45  6s/2p  Concentrated  Solid PM  Gas Blower 
[86]  3  150  24s/2p  Overlapping (Fullpitched)  Solid PM  Prototype 
[15]  3  150  6s/2p  Concentrated  SPM   
[44]  3  100  12S/2P  Overlapping (Fullpitched)  SPM  Electric Turbocharger 
[62]  3  80  6s/2p  Concentrated  SPM  Compressor 
[49]  3  80  6s/4p  Concentrated  SPM  Prototype 
[52]  2.5  100  6s/2p,4p  Concentrated  SPM  Prototype 
[83]  2  200  Slotless/2p  Overlapping (Fullpitched)  Solid PM  Prototype 
[29]  2  200  Slotless/2p  Overlapping (15/18 shortpitched)  Hollow shaft  Cryogenic 
[53]  2  120  6s3s/2p  Concentrated  SPM  Turbocharger 
[56]  1.5  150  6s/2p  Concentrated  SPM  Automotive Supercharger 
[76]  1.5  60  3s/2p  Concentrated  SPM  Spindle Machine Tool 
[152]  1.5  20  slotless/2p  Overlapping (Fullpitched)  SPM  Flywheel 
[23]  1.5  18  36s/4p  Overlapping (Fullpitched)  IPM  Prototype 
[103]  1.5  12  3s/2p  Concentrated  SPM  Small UrbanType Vehicle 
[67]  1.3  120  3s/2p  Concentrated  SPM  Prototype 
[1]  1.3  20  Slotless/2p  Overlapping (Fullpitched)  SPM  Friction Welding Unit 
[21]  1.3  20  3s/2p  Concentrated  SPM  Electric Drives 
[69]  1  40  3s/2p  Concentrated  SPM  Handtool 
[69]  1  40  Slotless/2p  Overlapping (Fullpitched)  SPM  Handtool 
[37]  0.75  60  24s/2p  Toroidal  Solid PM  Prototype 
[45]  0.5  100  12s/4p; 2p  Overlapping (Fullpitched)  SPM  Miniature Turbojet 
[60]  0.4  200  6s/2p  Concentrated  Solid PM  Micro Turbine Generator (MTG) 
[31]  0.15  1200  Slotless/2p  Toroidal  Solid PM  Prototype 
[98]  0.15  200  Slotless/2p  Toroidal  SPM  Micromilling Spindle 
[80]  0.1  500  Slotless/2p  Concentrated  SPM  Micro Gas Turbines 
[79]  0.1  500  Slotless/2p  Overlapping (Fullpitched)  Solid PM  Prototype 
[1]  0.05  150  3s/2p  Concentrated  SPM  Handtool 
[80]  0.04  400  Slotless/2p  Concentrated  SPM  Micro Gas Turbines 
[98]  0.03  90  Slotless/2p  Toroidal  SPM  Air Compressor 
[26]  0.01  150  3s/2p  Concentrated  Solid PM  Handtool 
[82]  160  Slotless/2p  Toroidal  Solid PM  Electrical Drive Systems  
[94]  40  Slotless/2p  Overlapping (Fullpitched)  SPM  Handtool 
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Advantages  Disadvantages  

Singlephase PM machine 


Threephase PM machine 


Slotted  Slotless  

Application 


Advantages 


Disadvantages 


Overlapping  NonOverlapping  

FullPitched  ShortPitched  Concentrated  Toroidal  Skewed  
Applications  Multislot; Slotless  Multislot; Slotless  Multislot; Minimalslot; Slotless  Multislot; Minimalslot; Slotless  Slotless 
Advantages 





Disadvantages 





IPM  SPM  Solid PM  

Application 



Advantages 



Disadvantages 



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He, T.; Zhu, Z.; Eastham, F.; Wang, Y.; Bin, H.; Wu, D.; Gong, L.; Chen, J. Permanent Magnet Machines for HighSpeed Applications. World Electr. Veh. J. 2022, 13, 18. https://doi.org/10.3390/wevj13010018
He T, Zhu Z, Eastham F, Wang Y, Bin H, Wu D, Gong L, Chen J. Permanent Magnet Machines for HighSpeed Applications. World Electric Vehicle Journal. 2022; 13(1):18. https://doi.org/10.3390/wevj13010018
Chicago/Turabian StyleHe, Tianran, Ziqiang Zhu, Fred Eastham, Yu Wang, Hong Bin, Di Wu, Liming Gong, and Jintao Chen. 2022. "Permanent Magnet Machines for HighSpeed Applications" World Electric Vehicle Journal 13, no. 1: 18. https://doi.org/10.3390/wevj13010018