SENSORLESS FIELD ORIENTED CONTROL OF BRUSHLESS ...

List of Figures
Figure 2.1 – Radial- and axial- flux motors...................................................................................11
Figure 2.2 – Outer- and inner- rotor radial flux motors. ................................................................12
Figure 2.3 – General categorization of machines. .........................................................................13
Figure 2.4 – Motors categorized by presence or absence of brushes............................................. 14
Figure 2.5 – Motors categorized by power supply type.................................................................15
Figure 2.6 – General motor taxonomy used in this report. ............................................................16
Figure 2.7 – Cross sections of some generalized synchronous motors..........................................19
Figure 2.8 – Demonstration of Faraday & Lentz laws; generator.................................................. 23
Figure 2.9 – Electrical model of ideal coil shunted by an external resistance. ..............................24
Figure 2.10 – Demonstration of the Lorentz Force law; motor. .................................................... 26
Figure 2.11 – Electrical model of coil connected to voltage source. .............................................26
Figure 2.12 – Section view of a general brushless PM motor. ......................................................28
Figure 2.13 – Developed view showing only ideal rotor flux density...........................................29
Figure 2.14 – Magnetic circuit of Figure 2.12. ..............................................................................30
Figure 2.15 – Simplified magnetic circuit of Figure 2.12..............................................................30
Figure 2.16 – Components of total flux (cf. Figure 2.15).............................................................. 31
Figure 2.17 – Per-phase electrical model of general brushless PM motor; explicit inductor. .......34
Figure 2.18 – Per-phase electrical model of general brushless PM motor; explicit inductor. .......34
Figure 2.19 – Per-phase electrical model of general brushless PM motor; implicit inductor........34
Figure 2.20 – Elementary brushless PM motors with concentrated full-pitch winding.................37
Figure 2.21 – Airgap flux density profiles for two BPMS motors.................................................37
Figure 2.22 – Torque functions of sinusoidal and arbitrary trapezoidal motors............................39
Figure 2.23 – Simulation diagram for per-phase torque function..................................................39
Figure 2.24 – Back EMF functions of a sinusoidal and arbitrary trapezoidal motor.....................40
Figure 2.25 – Simulation diagram for per-phase bEMF function..................................................41
Figure 2.26 – Rotor-stator flux linkage for a sinusoidal and arbitrary trapezoidal motor. ............44
Figure 2.27 – Simulation diagram of general motor......................................................................48
Figure 2.28 – Phase-variable simulation diagram of general motor. .............................................49
Figure 2.29 – Back-EMF and drive current for sinusoidal BPMS motor. .....................................53
Figure 2.30 – Torque production in sinusoidal BPMS motor........................................................54
Figure 2.31 – Back-EMF and drive current for trapezoidal BPMS motor.....................................55
Figure 2.32 – Torque production in trapezoidal BPMS motor. .....................................................56
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