Re: [CAD_CAM_EDM_DRO] ac servo motors

I don't know that has been done with PM AC servos. It is common on
induction motors, but normally only for medium to low performance velocity
control. High performance servo control normally needs positive position
feedback. You might be stuck with landfill unless you want to get into
power electronics design issues. AC servos are not like DC, the drives and
motors on AC servos are designed together. The only controller I have seen
that appears to do much for controlling commutation is Delta Tau. The last
time I looked at their offerings (a few years back) they had commutation
control but there were no commercially available drivers that accepted
external commutation. I think Delta Tau offered the feature for OEM's who
wanted to make their own drives but didn't want to do the commutation
issues. I know I considered it every time our power electronics designers
would blow up something. Direct switching and power control seemed easy.
They kept screwing up on the commutation section of the motor drivers.

GTJ

At 01:46 PM 2/15/01 -0800, you wrote:

>
>Upon opening them there are no sensor leads...just
>the three phase leads. So......are these driven by
>picking off phase and amplitude and using a dsp to
>provide control?
>
>