I try run a BLDC motor from a hoverboard with VESC. My challange is to run the motor very slow, about 10rpm.
I started with FOC using the integrated hall sensors. Fine but it is not possible to rotate the motor really slow.
I attached an AS5047 encoder because I thought that the resolution of the hall sensors is probably not sufficient to let the speed PID controller work properly.
With the AS5047 is see the following
setting duty cycle to about 12% (no PID) rpm is swinging between 600rpm and 800rpm.
with lower duty cycles about 1% (no PID) rpm is jumping to 30 going back to 0 for a while than become -10 and jump back to 30. Motor is not really spinning.
Activating the PID speed controller does not help.
Am I totally wrong about what can be done with a BLDC motor? With a brushed motor and a high resolution encoder it is no problem to run 10rpm.