VFD with external position loop controller

[hamradio]

Hi everyone.We need some advice on what "control mode" would be the best to use in a Yaskawa G7, 55 KW drive. We are using a 2 axis Galil motion controller ,and a 75 HP Baldor/Reliance L3272A induction motor. The Galil motion controller is controlling 2 of these systems for very accurate position control between these two motors. I have setup over 100 bldc servo drives using Galil,but a VFD sure is different.So far we have had some good success with (V/F) and (flux/vector) by turning all the gains down to zero. Remember, the PID loop is in the Galil. Every time we call the manufacturer for advice, we get a different answer. Maybe its because different modes give the same result. Just wondering what the best "control mode" would be. Would an F7 drive do just as good, sense galil is doing the PID work. Thanks in advance and Merry Christmas.

 

[DickDV]

The following is based on the assumption that the positioning control is done entirely by the Galil controller with the Yaskawa drive simply following speed and direction commands from the positioning controller.

If that is your situation, then the Yaskawa VFD needs to be set up as a vector speed controller with the tightest possible speed loop tuning for maximum dynamic response and minimum speed error.

Your Galil positioning controller then does all the positioning work with the positioning loop tuning there as well as error generation, etc.

Do not try to mix the controls. Let the Galil do all of the positioning and the Yaskawa follow all of the speed and direction commands.