AC servos like the Omron and Yaskawa (I believe the Omrons maker) as well as Fanuc,Meldas(mitsubishi)
all use the keyed and aligned built-in encoder for the commutation.
these motors MUST be used with the drive that is built
for them, as the encoder connects to the drive for feedback
The same encoder provides all the needed feedback
position,phase angle(commutation) and velocity. |