motor with more poles give more torque?

Joined
Apr 25, 2014
Messages
2,782
Location
Sausalito
In my mind the difference of having more poles is of benefit as it equates to a smaller distance between poles and teeth when they're energized. the scenario with double the poles is you have a magnet at half the size and therefore half the strength but also at half the distance and the strength of the field increases at a square relationship to distance so the motor with double the poles would be able to produce more torque.. No?

Ive done simulations and they were flawed and also talked to two consultants who wrote a book on bldc motor design and they insisted the greater amount of poles is only slightly an advantage for producing more torque as it enables the back iron to be thinner so the airgap diameter, with the same thickness, could be moved a bit further to the outside of the motor. For example the stator would maybe go from 47mm diameter to 48 and the same magnet size and airgap thickness but with the thinner backiron.

of course more poles will give a lower kv but will it truly produce more torque regardless of the kv?
 
Back
Top