Re: [CAD_CAM_EDM_DRO] Re: Ordinary AC motors & position control

At 08:49 AM 6/19/2007, you wrote:

>You can't use a single phase AC motor and any thoughts of converting
>one to the other are going to cost you in time and money and
>probably won't work anyway.

However, a poly-phase (3 phase being most common) motor can work in
this mode IF it has position feedback (so the phases can be energized
or de energized properly) and it can be "micro-stepped" just like a
stepper. With an analog driver, position can be pretty well set by
varying each phase current separately so the magnetic field pulls the
rotor to position.

It is not a trivial circuit to design and the likelihood is that an
embedded microcontroller would be desirable.

David G. LeVine
Nashua, NH 03060