Control schematics in sensorless control

Hi folks,

Does this control scheme apply when in sensorless mode?

If it applies:

  • do we also have the possibility to apply a current feed-forward along with the velocity setpoint?
  • would it be possible to control current directly in sensorless mode?

If not:

  • what is actually happening in sensorless velocity control in a schematic level?

Thanks in advance!

Yes the same control scheme applies. Sure you can control current directly instead of velocity, or add current feed-forward during velocity control. Just make sure that the motor doesn’t fall below a certian RPM (the value varies), because then the sensorless estimator stops working.