Anyone used permanent magnet motors with VFDs like ABB ACS355/ACS800

[Pete.S.]

Great info guys!

I'm going to run some test with an encoder to see what kind of performance I'll get. It sure sounds like that might be a better solution than a PM motor if I don't need the increased efficiency of the PM motor.

 

[Highland Controls]

The ACS355 can do it, and I have tried it. Keep in mind that the ACS355 is not a high performance drive, no matter what motor(and encoder) you put on it. The MTAC module does nothing for the torque loop, only the velocity loop. The lines are really becoming blurred in drives, ie servo vs. regular VFD. I have done motion control applications with induction motors with good results. I have also used the same drives for PM and induction motors. You should look at the ABB ACSM1 or ACS850, or the KEB F6 or S6. Those drives can actually run permanent magnet motors open loop, though not well at low speed, and I wouldn't use them for positioning applications without feedback.