AVR-Chat

> ... In a PWMed brushless DC motor, for example, there are three 
"phases"...

Yes, I understand that quite well.  I question the terminology.

Is a brushless DC motor just the frame, stator and armature?  I suggest 
that it is not, that it isn't a brushless DC motor unless it includes 
the drive; until then, it is a three-phase motor with open coils, is it not?

If that is correct, PWM'ing a DC brushless motor involves just two 
leads, the DC power to the drive; the coils are downstream from the 
drive and semi-insensitive to the PWM frequency - they certainly are not 
locked to the DC power PWM frequency, as stated.  If the DC power to the 
drive is PWM'ed, variable power is delivered to the drive, modulating 
torque, thus speed, no?

I am balking at the notion of fixed pulse-width, three-phase drive being 
called PWM.


Tom