Sensorless control help


#1

When I use the sensorless method, plus the speed loop and the current loop, after adding the load, the direction of rotation of the motor has changed. Why?


#2

Did you let the motor stop? If the motor stops, then sensorless stops working.
Also can you show a video?


#4

Thanks for you replay, this problem trouble me a long time. I upload the video to the YouTube. https://youtu.be/RCMncyBk9O4. In the video, when I use hand gently to catch the motor, the direction is changed.


#5

Yes, we currently don’t have stall detection on the sensorless mode, and actually sensorless is not very supported yet. Sorry.


#7

Is there any reason to explain why the motor will change direction when there is load?
I want to understand this intermediate process,so we can solve this problem。Thank you for your help!


#8

I think actually your motor never spun up fast enough during the initial spin-up. If it goes too slow, then the rotor estimator doesn’t have enough back-emf over the current sensing noise to be detectable, so it just does something semi-random.