1. © The McGraw-Hill Companies, Inc. 2000 McGraw-Hill 1 PRINCIPLES AND APPLICATIONS OF ELECTRICAL ENGINEERING THIRD EDITION G I O R G I O R I Z Z O N I 18 Special-Purpose Electric Machine

2. © The McGraw-Hill Companies, Inc. 2000 McGraw-Hill 2 PRINCIPLES AND APPLICATIONS OF ELECTRICAL ENGINEERING THIRD EDITION G I O R G I O R I Z Z O N I Figure 18.1(a) Two-pole brushless DC motor with three-phase stator winding

3. © The McGraw-Hill Companies, Inc. 2000 McGraw-Hill 3 PRINCIPLES AND APPLICATIONS OF ELECTRICAL ENGINEERING THIRD EDITION G I O R G I O R I Z Z O N I Figure 18.3 Transistor and SCR drives for a brushless DC motor

4. © The McGraw-Hill Companies, Inc. 2000 McGraw-Hill 4 PRINCIPLES AND APPLICATIONS OF ELECTRICAL ENGINEERING THIRD EDITION G I O R G I O R I Z Z O N I Figure 18.4 Phase voltages and transistor (SCR) switching sequences for the brushless DC motor drive of Figure 18.3

5. © The McGraw-Hill Companies, Inc. 2000 McGraw-Hill 5 PRINCIPLES AND APPLICATIONS OF ELECTRICAL ENGINEERING THIRD EDITION G I O R G I O R I Z Z O N I Figure 18.5 Performance and efficiency characteristics of brushless DC motor

6. © The McGraw-Hill Companies, Inc. 2000 McGraw-Hill 6 PRINCIPLES AND APPLICATIONS OF ELECTRICAL ENGINEERING THIRD EDITION G I O R G I O R I Z Z O N I Figure 18.8 Stepping motor configurations