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Old 03-02-2009, 04:28 PM   #7 (permalink)
MazdaMatt
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Join Date: Jun 2008
Location: London, Ontario
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2k2Prot5 - '02 Mazda Protege5
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I'm interested in the often repeated advantage number one. "AC can be more efficient". Why is this? Is it because the proximity from the winding to the pole is actual a perfect sinusoid? I have read that driving an AC motor with a square wave, or a 6-step is inefficient - isn't a DC motor just the same as an AC motor except that it mechanically transforms the DC signal into a square wave AC? (what's that part called, the commutator or something?)

This Field Oriented Control concept is very interesting. It would be worthwhile to design a controller that has all the inputs required to use FOC, but start with a simple Volts/Hz controller. That paper shows massive advantages to FOC over V/Hz - specifically, it shows "DC motor-like" low-end torque... which is one of the main benefits of a DC motor.

btw, LOVE the motor sound
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