Operating Procedure - Omron G5 Series User Manual

6 Applied Functions

6-15-3 Operating Procedure

Speed Feed-forward Operating Method
1
Set Speed Feed-forward Command Filter (Pn111).
Set this to approximately 50 (0.5 ms).
2
Adjust Speed Feed-forward Amount (Pn110).
Gradually increase the value set in Speed Feed-forward Amount (Pn110) and finely adjust it to
avoid overshooting during acceleration/deceleration.
If Speed Feed-forward Amount is set to 100%, the position error is calculated as 0. However,
large overshooting will occur during acceleration/deceleration.
The position error when the Servomotor is operating at a constant speed will decrease based on
the following formula according to the speed feed-forward gain value.
Position error [command units] = Command speed [command units/s]/Position Loop Gain [1/s] x
The position error in the constant speed range becomes smaller as the speed feed-forward gain
increases.
Precautions for Correct Use Precautions for Correct Use
If the update cycle of the position command input is longer than the Servo Drive control cycle, or
if the pulse frequency is not uniform, operating noise may increase while the speed feed-forward
is enabled. Apply the position command filter (first-order lag or FIR smoothing) or increase the
speed feed-forward filter value.
6 - 48
(100 – Speed Feed-forward Amount [%])/100
Position error
Motor speed
Command
speed
OMNUC G5-series (Pulse-train Input Type) AC Servomotors and Servo Drives User's Manual
Speed FF gain
0 [%]
50 [%]
80 [%]
Time