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9.2.3. Feed Forward Compensation
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Parameter “FF” sets feed forward compensation gain. The password is necessary when setting.
l
Shipping set of “FF” is FF0.
l
The feed forward compensation function generates a velocity command by differentiating the
position command, then adds it to the velocity loop in the forward direction.
l
Feed forward compensation improves follow-up delay during acceleration/deceleration.
l
Setting the FF parameter to a higher value improves follow-up delay, but overshoot becomes
more likely to occur. It is generally recommended that the parameter be set to 0.5 or below.
Figure 9-17: Feed Forward Compensation Block Diagram
+
+
Position
command
Velocity
c
–
+
–
Position data
Differentiation
Position
loop gain
Feed forward
compensation
gain
Velocity data
FF
PG
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