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Design of Rotating Electrical Machines

Design of Rotating Electrical Machines

Juha Pyrhonen, Tapani Jokinen, Valeria Hrabovcova

ISBN: 978-0-470-74008-8

Feb 2009

538 pages

Select type: E-Book



In one complete volume, this essential reference presents an in-depth overview of the theoretical principles and techniques of electrical machine design. This book enables you to design rotating electrical machines with its detailed step-by-step approach to machine design and thorough treatment of all existing and emerging technologies in this field.

Senior electrical engineering students and postgraduates, as well as machine designers, will find this book invaluable. In depth, it presents the following:

  • Machine type definitions; different synchronous, asynchronous, DC, and doubly salient reluctance machines.
  • An analysis of types of construction; external pole, internal pole, and radial flux machines.
  • The properties of rotating electrical machines, including the insulation and heat removal options.

Responding to the need for an up-to-date reference on electrical machine design, this book includes exercises with methods for tackling, and solutions to, real design problems. A supplementary website hosts two machine design examples created with MATHCAD: rotor surface magnet permanent magnet machine and squirrel cage induction machine calculations. Classroom tested material and numerous graphs are features that further make this book an excellent manual and reference to the topic.

About the Authors.


Abbreviations and Symbols.

1 Principal Laws and Methods in Electrical Machine Design.

1.1 Electromagnetic Principles.

1.2 Numerical Solution.

1.3 The Most Common Principles Applied to Analytic Calculation.

1.4 Application of the Principle of Virtual Work in the Determination of Force and Torque.

1.5 Maxwell’s Stress Tensor; Radial and Tangential Stress.

1.6 Self-Inductance and Mutual Inductance.

1.7 Per Unit Values.

1.8 Phasor Diagrams.


2 Windings of Electrical Machines.

2.1 Basic Principles.

2.2 Phase Windings.

2.3 Three-Phase Integral Slot Stator Winding.

2.4 Voltage Phasor Diagram and Winding Factor.

2.5 Winding Analysis.

2.6 Short Pitching.

2.7 Current Linkage of a Slot Winding.

2.8 Poly-Phase Fractional Slot Windings.

2.9 Phase Systems and Zones of Windings.

2.10 Symmetry Conditions.

2.11 Base Windings.

2.12 Fractional Slot Windings.

2.13 Single- and Two-Phase Windings.

2.14 Windings Permitting a Varying Number of Poles.

2.15 Commutator Windings.

2.16 Compensating Windings and Commutating Poles.

2.17 Rotor Windings of Asynchronous Machines.

2.18 Damper Windings.


3 Design of Magnetic Circuits.

3.1 Air Gap and its Magnetic Voltage.

3.2 Equivalent Core Length.

3.3 Magnetic Voltage of a Tooth and a Salient Pole.

3.4 Magnetic Voltage of Stator and Rotor Yokes.

3.5 No-Load Curve, Equivalent Air Gap and Magnetizing Current of the Machine.

3.6 Magnetic Materials of a Rotating Machine.

3.7 Permanent Magnets in Rotating Machines.

3.8 Assembly of Iron Stacks.

3.9 Magnetizing Inductance.


4 Flux Leakage.

4.1 Division of Leakage Flux Components.

4.2 Calculation of Flux Leakage.


5 Resistances.

5.1 DC Resistance.

5.2 Influence of Skin Effect on Resistance.

6 Main Dimensions of a Rotating Machine.

6.1 Mechanical Loadability.

6.2 Electrical Loadability.

6.3 Magnetic Loadability.

6.4 Air Gap.


7 Design Process and Properties of Rotating Electrical Machines.

7.1 Asynchronous Motor.

7.2 Synchronous Machine.

7.3 DC Machines.

7.4 Doubly Salient Reluctance Machine.


8 Insulation of Electrical Machines.

8.1 Insulation of Rotating Electrical Machines.

8.2 Impregnation Varnishes and Resins.

8.3 Dimensioning of an Insulation.

8.4 Electrical Reactions Ageing Insulation.

8.5 Practical Insulation Constructions.

8.6 Condition Monitoring of Insulation.

8.7 Insulation in Frequency Converter Drives.


9 Heat Transfer.

9.1 Losses.

9.2 Heat Removal.

9.3 Thermal Equivalent Circuit.


Appendix A.

Appendix B.