I have a question about the electrical angle and mechanical angle of the BLDC motor.
The motor has 8 poles. We have
Electrical angle = number of pole pair * mechanical angle
This would mean that if the mechanical angle covers 45 deg, the electrical angle has spanned 360 deg. After that, should I reset my electrical angle to 0 and start counting again, or it's acceptable if the electrical angle keeps increasing?
I use the electrical angle in the Park transformation for calculations.
Best Answer
What is key is the electrical frame of reference. Every pole-pair the cycle completes.
For a 6 pole machine, 3pole-pair, this wrap (in the mechanical frame of reference) is every 120degrees
For an 8 pole machine, 4pole-pair, this wrap (in the mechanical frame of reference) is every 90degrees.
If you unwrap a machine stator (see below for a 2pole-pair) the difference becomes clear