1. for traction applications
Control of PMSM drives
for traction applications
Speaker : Magyari Györgyi-Karola

2. Contents PMSM drives classification brushless a.c. drive controls
control loops with PID-type controllers
rules for the controllers settings
conclusions

3. PMSM drive classification
with respect to current waveform
voltage-frequency correlation
motion sensor presence

4. PMSM drive classification
From the point of view of the current waveform :
rectangular current control brushless d.c. motor dive
sinusoidal current control brushless a.c. motor drive
Rectangular and sinusoidal current control

5. PMSM drive classification
Brushless d.c drives:
q=1
concentrated coil stator windings
surface magnets
Brushless a.c drives:
q≥1
distributed coil stator windings
surface and interior magnets

6. Brushless a.c. drive control
scalar control (V/f): a damper cage on the rotor is required, there are no motion sensors low dynamics applications
vector control (current or current and voltage): faster dynamics applications
direct torque and flux control

7. Brushless a.c. drive control
Basic vector control of PMSM: 1 - with motion sensor
2 - sensorless

8. Control loops to control currents, speed, position in PMSM drive
heavily affects the performances of the drive system
to optimize the time domain step response of the system or the performances in the frequency domain
PI-type controller

9. Rules for the control settings
symmetrical optimum (SO):
a PI controller is designed to control a system with an I-element
absolute value optimum (AVO):
a PI controller operates in a control system with one long delay time and a sum total of smaller delay times

10. Control settings

11. Control settings

12. Conclusions
each control loop can be adjusted efficiently and independently
multiple delay times can be reduced or canceled for the higher level controller with compensation in a lower level
disturbance variables will be corrected in lower level control loops
internal control variables can be limited through the command variable
each additional control loop introduces delay time to the higher level, so the changes in the command variables need more time to be corrected

13. Thank you for your attention!!!