Re: [CAD_CAM_EDM_DRO] AC Servo Motor/Drive Specification

rjh@... wrote:

> How is an ac servo motor matched to an ac servo drive? - I am
> concerned about voltage ratings... do the voltage ratings of the
> motor windings simply have to withstand the dc link voltage of the
> drive or is it more complicated than this?

Mostly, but there's a lot more. Some old 'brushless' drives generated
constant-current waveforms, and handled the motor much like a
brushless motor in a disk drive. Ie. no attempt to simulate a sine
wave at all. Many of the new, larger AC drive motors won't like this
at all. The other thing is the arrangement of sensors for the commutation
of the motor, as well as any feedback, if the drive is a velocity drive.
There are dozens of different sensor arrangements used by different
manufacturers.

Finally, each motor has some specific voltage/RPM ratio, and the drive
has to be set to match that curve. For AC drives, it is roughly a straight
line that does not intercept the origin, as some additional excitation must
be supplied to excite the rotor poles.

Jon