1. PMSM Control Strategy Reference:
R. Krishnan, Permanent Magnet Synchronous and Brushless DC Motor
Drives, CRC, 2010.

2. Steady State Vector Diagram (1)Id Iq
d axis
jXqIq
jXdId lf
lnet ls
RsIa
q axis
leading power factor

3. Steady State Vector Diagram (2)
Neglect Rs Or Id Iq
d axis
jXqIq
jXdId lf
lnet ls
q axis
leading power factor

4. Steady State Vector Diagram (3)
Define
Close to Unity Power Factor

5. General Considerations
DC Motor
PMSM
Can use id for flux weakening control for IPM

6. General Control Block Diagram
PPU
Motor
DC Bus
Electrical Input
Mechanical Output
gate control signals
Controller
Reference

7. Motor Modeling (1)
abc to dq
Dynamical Equation
dq to abc

8. Motor Modeling (2)

9. Inside the Controller abc to dq Position Controller Speed Controller
gate control signals
actually need two of them
abc to dq
Position
Controller
Speed Controller
Current
Controller
d/dt
* For reference

10. Example: Hysteresis Current Controller
* For reference
gate control signals
dq Current
Calculator
dq to
abc
Hysteresis
Controller
Current Controller
Algorithm:

11. Example: PI Current Controller
gate control signals

12. PMSM Control Strategies
Constant Torque and Flux Control
Zero Direct Axis Current Control
Unity Power Factor Control
Given Power Factor Control
Optimum Torque per Unit Current Control
Constant Power Loss Control
Maximum Efficiency Control

13. Constant Torque and Flux Control
Solve (transcendental)
equations
One choice would be:
SPM
dq Current
Calculator

14. Zero Direct Axis Current Control
dq Current
Calculator
Steady State

15. Unity Power Factor Control
dq Current
Calculator
Solve (transcendental)
equations

16. Given Power Factor Control
dq Current
Calculator
Solve transcendental
equations

17. Optimum Torque per Unit Current Control (1)
dq Current
Calculator

18. Optimum Torque per Unit Current Control (2)
dq Current
Calculator

19. Constant Power Loss Control
dq Current
Calculator
In the implementation, flux weakening
needs to be considered.

20. Maximum Efficiency Control