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Electronics => Beginners => Topic started by: sean87 on October 31, 2017, 05:26:35 pm

Title: Difference in commutation of brushless motor against pole numbers
Post by: sean87 on October 31, 2017, 05:26:35 pm

Hi all,

I have a BLDC motor with HALL sensors. Datasheet reads the motor is 4 pole. Somewhere else it says "Number of pole pairs 2"...I assume they both mean the same thing???
It also has 3 HALL sensors at 120°

I have some code samples that are for a 6 pole motor. My question is, what would be fundamentally different in commutation of a BLDC motor in respect to the number of poles.

Title: Re: Difference in commutation of brushless motor against pole numbers
Post by: Brumby on October 31, 2017, 10:34:21 pm

Quote from: sean87 on October 31, 2017, 05:26:35 pm

Datasheet reads the motor is 4 pole. Somewhere else it says "Number of pole pairs 2"...I assume they both mean the same thing???

The pole count is a simple counting exercise.
Poles tend to work in pairs groups.  A group of 2 is common.

So  4 = 2 x 2  looks right to me.