Analysis and Mathematical Models of Canned Electrical Machine Drives (eBook)

Qiang Yu received his Ph.D. degree from University of Bundeswehr Muenchen, Munich, Germany in 2012. From 2008-2012 he was an engineer in FEAAM GmbH, Neubiberg, Germany, where he hosted the project “design and analysis of high efficient canned switched reluctance machine drives for hydraulic pump drives”, with KSB Aktiengesellschaft, Frankental, Germany. From 2013-2014 he was a postdoctoral research associate at Automotive Resource Center, McMaster University, Ontario, Canada, where he hosted the project “high efficient rare-earth free machine drives”. From 2014-2015 he was a postdoctoral research fellow in Universite Libre de Bruxelles, Brussels, Belgium, with a European funded project “DeMoTest EV” (Design, Modeling and Test of Electrical Vehicles). Currently he is an associate professor in School of Electrical and Power Engineering, China University of Mining and Technology. His main research interests include electromagnetic and thermal analysis of electrical machines, canned machine drives and mathematical modeling of electrical machines.Xuesong Wang received her Ph.D. degree from China University of Mining and Technology in 2002. She is currently a professor in School of Information and Control Engineering, China University of Mining and Technology. Her main research interest includes electrical drives, bioinformatics, and artificial intelligence. In 2008, she was the recipient of the New Century Excellent Talents in University from the Ministry of Education of China. Yuhu Cheng received his Ph.D. degree from the Institute of Automation, Chinese Academy of Sciences in 2005. He is currently a professor in School of Information and Control Engineering, China University of Mining and Technology. His main research interest includes electrical drives and intelligent systems. In 2010, he was the recipient of the New Century Excellent Talents in University from the Ministry of Education of China. Lisi Tian received his Ph.D. degree from Huazhong University of Science and Technology (HUST), China in 2015. He is currently with the School of Electrical and Power Engineering, China University of Mining and Technology. His main research interests include power electronics, electrical drives and fault diagnosis.

Preface 5
Acknowledgments 6
Contents 7
About the Authors 10
List of Figures 12
List of Tables 20
Chapter 1: Overview of Canned Electrical Machines 22
1.1 Background 22
1.2 Research Overview 24
1.2.1 Structural Topology 25
1.2.2 Loss Analysis 26
1.2.3 Thermal and Acoustic Analysis 27
1.2.4 Review Summary 28
1.3 Canned Switched Reluctance Machines 28
1.4 Outline Summary 29
References 31
Chapter 2: Electromagnetic Analysis of Saliency and Can Effect by Network Models 33
2.1 Flux Linkage Modeling of Switched Reluctance Machines 33
2.2 A Discretized Circuit Network Model 36
2.2.1 Modeling of Airgap Reluctance 36
2.2.1.1 Non-overlap Positions 36
2.2.1.2 Partial and Full Overlap Positions 38
2.2.2 Modeling of Pole Reluctance 38
2.2.3 Modeling of the End Part 40
2.2.4 Calculation Flow 40
2.2.5 Application Examples 41
2.2.6 Can Loss Analysis 44
2.3 Loss and Efficiency Analysis 49
2.3.1 The Calculation Method 49
2.3.1.1 Eddy Current Loss 51
2.3.1.2 Hysteresis Loss 52
2.3.1.3 Comparison and Discussion 54
2.3.2 The Variable Loss Coefficients 55
2.3.3 The Discretized Elements 57
2.3.4 Verification and Discussion 59
2.4 A Simplified Network Model 62
2.4.1 The MEC-FE Model 62
2.5 A Fitting Method for Airgap Reluctance 69
2.6 Chapter Summary 73
References 74
Chapter 3: Electromagnetic Analysis of Can Effect of a Canned SRM 77
3.1 Canned Switched Reluctance Machine and Operation Principles 77
3.2 Eddy Current and Loss Features at Typical Rotor Positions 81
3.2.1 Single Phase Excitation 81
3.2.2 All-Phase Excitation 82
3.3 Can Loss Variation of One Stroke Period 83
3.4 Airgap Flux and Eddy Current Loss Due to the Use of Cans 86
3.5 Experimental Validation 87
Reference 90
Chapter 4: An Analytical Model of Concentric Layer Structure for Canned Machines, Part I: Armature Coils 91
4.1 Model Introduction 91
4.2 Modeling of Winding Function 92
4.2.1 Fourier Approach for a Single Turn of Wire 92
4.2.2 Model of a Tooth Concentrated Coil with Wire Layout (Model 1) 96
4.2.2.1 Simplified Model of a Tooth Concentrated Coil (Model 2) 104
4.2.3 Model of One Coil in Distributed Topology 106
4.2.4 Model of Coil Distribution 108
4.3 Modeling of Phase Current 112
4.4 Modeling of MMF Distribution 114
4.4.1 Concentrated Coils 114
4.4.2 Distributed Coils 116
4.4.2.1 Sum of All Coils Within a Pole 117
4.4.2.2 Sum of All Poles Within a Phase 118
4.4.2.3 Sum of All Phases 118
4.5 Simulation and Discussion 120
4.6 MMF Distribution from Axial Direction 123
4.7 Application Example 124
4.8 Modeling of Permanent Magnets 126
4.9 Chapter Summary 131
References 132
Chapter 5: An Analytical Model of Concentric Layer Structure for Canned Machines, Part II: Magnetic Field 133
5.1 Model Introduction 133
5.2 The Model of Concentric Layer Structure 136
5.2.1 Vector Potential of the First Layer 138
5.2.2 Vector Potential of More Layers 140
5.2.3 Coordinate Transformation 141
5.2.4 Calculation of Constants 142
5.3 Magnetic Field due to DC Potential 145
5.4 Modeling of Saliency Effect 148
5.5 Feature Deduction 150
5.5.1 Flux Density of Stator 150
5.5.1.1 Stator Yoke 150
5.5.1.2 Stator Pole 151
5.5.2 Flux Linkage 152
5.5.3 Iron Loss 154
5.5.4 Can Loss 155
5.5.5 Torque 156
5.6 Verification and Discussion 159
5.6.1 Canned Induction Machine 159
5.6.2 Canned Permanent Magnet Machine 165
5.6.3 Canned Switched Reluctance Machine 171
5.7 Chapter Summary 173
References 174
Chapter 6: Thermal Analysis of a Canned SRM 177
6.1 Background 177
6.2 The Thermal Network Model 180
6.2.1 Model Overview 180
6.2.2 Heat Sources 181
6.2.3 Thermal Resistances 181
6.2.3.1 Conduction 182
6.2.3.2 Convection 183
6.2.3.3 Contact 185
6.2.3.4 Compensation Elements 185
6.2.4 Model of Coils 187
6.2.4.1 Overview 187
6.2.4.2 Resistances in the Windings 189
6.2.4.3 Resistances in the End Windings 191
6.2.4.4 Compensation Elements of a Coil 192
6.2.4.5 Model of the End Part 193
6.3 Application and Discussion 193
6.4 Electro-thermal Coupled Analysis 200
6.4.1 The Calculation Flow 200
6.4.2 Application and Discussion 202
6.5 Chapter Summary 203
References 204
Chapter 7: Conclusions and Future Work 205
7.1 Conclusions 205
7.2 Future Work 207
Appendix 208
A.1 Deduction of Fourier Coefficients of the Winding Function 208
A.2 Discretizing Phase Current into Fourier Series 209
A.3 Sum of Coils and Phases 211
A.4 Deduction of Constants 213
A.5 Calculation of Power 218