Omron R88D-KTA5L User Manual page 424

6-16 Feed-forward Function
Operating Procedure
Speed Feed-forward Operating Method
1. Set the Speed Feed-forward Command Filter (Pn111).
Set it to approx. 50 (0.5 ms).
2. Adjust the Speed Feed-forward Amount (Pn110).
Gradually increase the value of Speed Feed-forward Amount (Pn110) and finely adjust it to
avoid overshooting during acceleration/deceleration.
If the speed feed-forward amount is set to 100%, the position error will be 0 in calculation.
However, a large overshooting will occur during acceleration/deceleration.
The position error during an operation at a constant speed will decrease based on the following
formula according to the speed feed-forward gain value.
Position error [command unit] = command speed [command unit/s] / position loop gain [1/s] ×
6
The position error in the range of constant speed becomes smaller as the speed feed-forward
gain increases.
 The operating noise may increase when the speed feed forward is enabled if the update cycle of
the position command input is longer than the Servo Drive's control cycle, or if the pulse frequency
is not uniform. Apply the position command filter (first-order lag or FIR smoothing) or increase the
speed feed-forward filter setting.
6-52
Position error
Motor speed
Command
speed
Precautions for Correct Use
OMNUC G5-SERIES AC SERVOMOTOR AND SERVO DRIVE USER'S MANUAL
(100 - speed feed-forward amount [%]) / 100
Speed feed-forward gain
0 [%]
50 [%]
80 [%]
Time