brushless motor power supply

Is there any way to drive a brushless motor (AC power supply) other than spending a load of money on a ESC? easy with DC but AC is another k.o.f
altogether,
regards, Terry
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| Is there any way to drive a brushless motor (AC power supply) other | than spending a load of money on a ESC? easy with DC but AC is | another k.o.f altogether,
I'm not sure exactly what you're asking.
Brushless motors are powered by three phase AC. There's no difference between a brushless motor and a three phase AC motor -- they're the same thing. A brushless ESC merely takes DC input and approximates a three phase AC output (but the frequency varies as the motor speed varies, which it reads via sensors (sensored) or by looking at the back-EMF produced by the motor (sensorless).)
As for powering it from one phase AC (like you have in your house), I don't know. I think you can power a three phase motor with one phase AC under some conditions, but at a loss of efficiency and there's a problem with getting it started. And of course the rotational rate will be probably be very low (and fixed!) if only powered by 60 Hz.
I don't see much of an alternative to putting together most of a brushless ESC to power your motor. (I say `most' because you wouldn't need the part that reads the servo signal, assuming you just want it running full-out.) Of course, you'd also need to rectify and smooth out the AC power ...
This wikipedia page --
http://en.wikipedia.org/wiki/Brushless_DC_electric_motor
is confusing, starting with the name, because it's NOT a DC motor at all! (They seem to explain this by making the ESC part of the motor, which I guess is a valid way of looking at it.)
But it does do a good job of explaining how they work.
--
Doug McLaren, snipped-for-privacy@frenzied.us Eschew obfuscation!

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Hi Doug, all a bit too complicated to be worth the effort then, was thinking on something for testing motors outside the a/c without a ESC, it is quite simple to convert AC to DC but wondered if it could be done the other way around but as you say it needs to be 3 phase and to make things that little bit more complicated I am in the UK where it is 220-240v and 50 ~,
regards, Terry
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Doug McLaren wrote:

Neither is a brushed motor a DC motor.
Its an AC motor with a sycnchronised mechanical AC convertor, called a commutator ;-)
Which sort of answers the original question.
"Yes, put a commutator and some brushes on it!"
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Terence Lynock (MSW) wrote:

Plenty,. but they are all more expensive..
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Goedendag Terry (Dutch_101)
Use a drill/dremel to spin a second brushless motor, this will generate 3phase AC which/that in turn can power the first motor.
Vriendelijke groeten ;-) Ron van Sommeren 14th.int. electric fly-in, Aug.26, Nijmegen, Netherlands http://home.hetnet.nl/~ronvans /
Terence Lynock wrote:

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