Hi,
I have one Stepper Motor with me. I need to use this Stepper Motor as normal motor. ( I mean I do not need any steps when it is rotating, it just needs to rotate as normal motor).
Does any body has some circuits to achieve this?
Thanks.
Irshad
Hi,
The two windings in some stepper motors are physically 90 degrees
apart from one another. This makes it possible i believe to run a
stepper motor from two AC (*NOT* DC) sinusoidal sources that
are 90 degrees out of phase with each other.
Since you need two AC sources that are out of phase with each other
and we usually only have one source available, a possibility would be
to use that one AC source and place a capacitor in series with it
to make the other 90 degree (well not exactly) out of phase source.
I cant give any details of what value the cap would have to be because
it will vary quite a bit with the stepper motor in question, but it will
probably have to be somewhat large and of course non polarized.
You could try several values such as 1uf, 2uf, 10uf, etc., until you
find one that works and still allows the motor to put out enough
torque. You also want to check that the motor doesnt get too hot.
My guess is that a large cap will work because the current will be
close to 90 degrees out of phase with the other AC current phase when
the cap value is large compared to the resistance of the winding.
OF COURSE you have to also watch the peak AC voltage applied too,
so the motor doesnt draw more than its rated current in each phase.
If the windings are not 90 degrees apart in a motor, then you have to
find a value of cap that provides for the right phase shift to match
the motor. This also means a little experimentation with different
value caps so either way you end up trying a few different value caps.