Fractional Slot Concentrated Windings

Design, Analysis, and Optimization
1. Auflage 2027
ISBN: 978-1-394-42392-7
Verlag: Wiley

Buch, Englisch, 304 Seiten

A consolidation of all known FSCW types and their optimization methods

Fractional Slot Concentrated Windings provides an in-depth analysis of fractional slot concentrated windings (FSCWs), reviewing theoretical foundations, existing FSCWs including three-phase and multiphase windings and their optimization methods, benefits, challenges, and solutions associated with FSCWs. Numerous winding topologies for real-world applications in traction motors, aerospace systems, robotics, industrial drives, and renewable energy systems are also included.

This book delves into detailed examinations of distinct winding groups and explores optimization techniques with dedicated chapters on specialized coil configurations. For each FSCW group, the main winding topologies and their associated winding layouts are explained.

Written by a highly qualified author in the field, this book includes information on: - Analytical approaches for the calculations of MMF characteristics and their winding factors
- A specific FSCW configuration with unequal zones and asymmetric zone distributions, expanding the spectrum of standard concentrated winding topologies
- Unique winding structures, such as the two-tooth coil-pitch design, alongside a review of star-delta combination concepts for FSCWs
- The flux-barrier technique, including the implementation of flux barriers in both the stator yoke and stator teeth regions
- Novel winding solutions for radial-flux and axial-flux machines

Covering principles, performance, and optimization, Fractional Slot Concentrated Windings serves as a comprehensive guide for engineers, researchers, and practitioners working with FSCWs in the design and optimization of modern electrical machines.

Autoren/Hrsg.

Dajaku, Gurakuq

Fachgebiete

• Technische Wissenschaften Elektronik | Nachrichtentechnik Nachrichten- und Kommunikationstechnik Regelungstechnik
• Technische Wissenschaften Energietechnik | Elektrotechnik Elektrotechnik
• Technische Wissenschaften Verfahrenstechnik | Chemieingenieurwesen | Biotechnologie Verfahrenstechnik, Chemieingenieurwesen

Inhaltsverzeichnis

Preface

1 Introduction 17

1.1 Stator Winding Types 3

1.2 Winding Realization 4

1.2.1 Number of layers 4

1.2.2 Coil polarity 4

1.2.3 Phase-zone 4

1.2.4 Base Winding 6

1.3 Winding Topologies 6

1.4 Fundamental Winding Specifications 7

1.4.1 Slots per pole and phase 8

1.4.2 Winding periodicity 8

1.4.3 Winding feasibility 8

1.4.4 Number of slots 8

1.4.5 Coil-pitch 9

1.4.6 Turns per coil and phase 9

1.5 MMF Harmonic Definition 9

1.6 Manufacturing Methods 10

1.7 Application 11

2 Standard FSCWs 12

2.1 Single-coil MMF Formulation 13

2.1.1 Definition of MMF parameters 14

2.1.2 Coil MMF function 16

2.2 MMF Analysis of Standard FSCWs 17

2.2.1 Single-layers FSCWs 17

2.2.2 Double-layer FSCWs 24

2.3 Winding Factors 28

2.3.1 Maximum winding factors 29

2.3.2 Selection of working harmonic 30

2.3.3 Winding factors for different single-layer FSCWs 31

2.3.4 Winding factors for different double-layer FSCWs 32

2.4 Three-Phase MMF Distribution 33

2.5 MMF Characteristics of Various Three-phase Standard FSCWs 35

3 FSCWs with Unequal Zones 45

3.1 Winding Configurations 46

3.2 MMF Analysis 48

3.2.1 Single-layers FSCWs with unequal zones 48

3.2.2 Double-layer FSCWs with unequal zones 54

3.2.3 FSCWs with asymmetric zone distribution 59

3.3 Winding Factors 67

3.3.1 Maximum winding factors 71

3.3.2 MMF working harmonics 75

3.4 MMF Characteristics of Various Three-phase FSCWs with Unequal Zones 76

4 FSCWs with Specific Coil Configuration 84

4.1 FSCWs with Asymmetric Coils 85

4.1.1 Coil MMF function 85

4.1.2 FSCWs with z=1, nc>1, and assymetric coils 88

4.1.3 FSCWs with z=2, nc>1, and asymmetric coils 90

4.2 FSCWs with Unequal Turns per Coil 93

4.2.1 FSCWs with z=1, nc>1, and unequal turns per coil 93

4.2.2 FSCWs with z=2, nc>1, and unequal turns per coil 97

4.3 FSCWs with Unequal Coil-Pitch 98

4.3.1 MMF aproach 99

4.3.2 Coil-pitch effect 100

4.5 Exemplary Windings with Special Coil Configurations 102

5 Multiphase FSCWs 105

5.1 Multiphase FSCW Topologies 106

5.1.1 Conversion of a three-phase FSCW into a six-phase winding 106

5.1.2 Other multiphase FSCW configurations 107

5.2 Multi Three-phase FSCWs 110

5.2.1 Asymmetric six-phase FSCW. 110

5.2.2 Asymmetric nine-phase FSCW. 113

5.2.3 Concluding remarks 116

5.3 FSCWs with an Arbitrary Number of Phases 117

5.3.1 MMF function analysis 118

5.3.2 Operation modes 121

5.3.3 Multiphase FSCWs with various slot/pole combination 123

5.4 Representative Multiphase FSCWs 125

5.4.1 Multiphase DL-FSCWs 125

5.4.2 Multiphase SL-FSCWs 127

5.4.3 Concluding remarks 130

6 FSCWs with Flux-Barrier Stator 131

6.1 Stator Flux-barrier Techniques 133

6.1.1 Flux barrier effect 133

6.1.2 Realization 135

6.2 FSCWs with Stator-yoke Flux Barriers 136

6.2.1 Equivalent MMF function 139

6.2.2 SL-FSCWs with stator-yoke flux-barrier 142

6.2.3 DL-FSCWs with stator-yoke flux-barrier 147

6.2.4 Key features and potentials 152

6.3 FSCWs with Stator-teeth Flux Barriers 154

6.3.1 SL-FSCWs with stator-teeth flux-barriers 157

6.3.2 SL-FSCWs with unequal zones and stator-teeth flux barriers 162

6.4 Multiphase SL-FSCWs with Flux-barrier Stator 164

6.4.1 Multiphase FSCWs with stator-yoke flux barriers 164

6.4.2 Multiphase FSCWs with stator-teeth flux barriers 169

7 Two-tooth FSWs 176

7.1 Implementation and Operating Principles 177

7.2 Single-layer Two-tooth/Three-phase FSWs 181

7.2.1 Single-layer FSWs with one zone/phase 181

7.2.2 Single-layer FSWs with two zones/phase 183

7.3 Double-layer Two-tooth/Three-phase FSWs 185

7.3.1 Double-layer FSWs with one zone/phase 185

7.3.2 Double-layer FSWs with two zone/phase 188

7.3.3 Double-layer FSWs with unequal-zones 189

7.4 Multiphase Two-tooth FSWs 191

7.4.1 Single-layer multiphase two-tooth FSWs 192

7.4.2 Double-layer multiphase two-tooth FSWs 196

7.4.3 Concluding remarks 200

7.5 Two-tooth FSWs with Specific Coil Configurations 200

7.5.1 Two-tooth FSWs with asymmetric coils 201

7.5.2 Two-tooth FSWs with unequal coils per zone 202

7.5.3 Two-tooth FSWs employing an unequal tooth-width stator core 205

8 FSCWs with Star-Delta Connection 208

8.1 Star-Delta windings 209

8.1.1 Star-delta phase currents 210

8.1.2 Winding MMF function 211

8.2 Star-Delta FSCW topologies 213

8.2.1 Symmetric star-delta FSCWs 214

8.2.2 Asymmetric star-delta FSCWs 217

8.3 Winding Analysis 219

8.3.1 Balanced star-delta FSCWs 220

8.3.2 Unbalanced star-delta FSCWs 226

8.3.3 Star-delta FSCWs with sinusoidal MMF distribution 231

8.3.4 Concluding remarks 232

8.4 FSCWs with Sequential Star-Delta Coil Arrangements 233

8.4.1 MMF winding function 235

8.4.2 FSCW examples with sequential star-delta coil arrangements 237

8.5 Star-Delta FSCWs with a Dual Slot-layers Stator 241

8.6 Exemplary Star-Delta FSCW Machines 243

9 FSCWs for Axial Flux Machines 248

9.1 AFMs - Construction and Realization 249

9.2 AFMs - Stator winding MMF Harmonics 250

9.3 Stator-shifting Technique for AFMs with Concentrated Windings 254

9.3.1 AFMs with double-layer FSCWs 254

9.3.2 AFMs with single-layer FSCWs 260

9.4 AFMs with Asymmetric Stator Shifting 262

9.5 AFMs with Unequal Turns per Coil 264

9.6 AFMs with Flux-Barrier Stator 264

9.7 AFMs Topologies 265

Bibliography 269

Über Autor(innen)

Gurakuq Dajaku is the CEO of FEAAM GmbH, the Research Center for Electrical Drives and Actuators Munich, Germany. He received the diploma degree in electrical engineering from the University of Prishtina, Kosova, in 1997, and the Ph.D. degree from the Universitaet der Bundeswehr Muenchen, Munich, Germany, in 2006. Dr. Dajaku has authored/co-authored numerous technical papers published in various IEEE conferences and journals and has several German and international patents and patent pending applications.