I asked BrianG this question a little while ago, and this was his response:
Quote:
Sensored motors have Hall-Effect sensors on the motor which provide feedback to the ESC so it knows where the rotor is. These sensors work well at very low rpms, which is where a sensorless has the most trouble.
A sensorless motor is built the same way as a sensored motor except it doesn't have the sensors. The ESC has to rely on the back-EMF pulses generated by the motor coils to determine rotor position. However, the rotor has to be actually turning to generate these pulses. Really, the only time a sensorless ESC has trouble is during startup or very low speeds (<1mph), but the advanced programming in todays ESCs generally address this very well.
IIRC, there are a couple sensored ESCs that start in sensored mode (using the motor sensors), but once they get up to speed, they then use the back-EMF pulses like a sensorless ESC.
|
Threaded Mode
