Originally posted by Ufopolitics
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I didn't want to go into fractions of degrees when broad principles establishes the point, but I can.
I referred to 'pole angles' as 'A' being 1/28 of 360°...which is 12.857°
The angle between P1C2 and P2C1, I referred to this as 'Z' being '5A' ...which is 64.285°
I notice you have indicated the brush width as being approximately 50% of the comm segment width, not full width as it is in my 12 pole motor. This reduces the sweep angle 'sA' before P2 disconnects from 12.857° to...6.428°
So
X + Z + sA + Y = 7A = 90°
Substituting
X + 64.285° + 6.428° + Y = 90°
X + Y = 19.287°
X is tunable in the region of 5° from previous posts AND
Y wants to be in the region of 20°
Which adds to more than 19.287°
Of course for the 12 pole 2 stator motor X and Y can not squeeze up to accommodate -
'Z' being '5A' being 5/12 of 360° ...which is 150°
The brush width being the comm width 'sA'...which is 30°
So
X + Z + sA + Y = 180°
Substituting
X + 150° + 30° + Y = 180°
X + Y = 0°
And therefore is not achievable.
However the 12 pole motor configured as '4 pole pairs' does work, I've done it. But it is determined by the flawed geometry to be inefficient as the leading coil remains energised past the magnet bisector and therefore contributes drag.
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