NSK MEGATORQUE M-ESB-YSB2020AB300 - Feed Forward Compensation

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7.2. For More Advanced Operation
7.2.4. Feed Forward Compensation: FF
7.2.4. Feed Forward Compensation: FF
Parameter: FF (The password is necessary.)
l A velocity command created by differentiating a position command may be fed to the velocity
loop in the forward direction.
l The feed forward compensation improves the tracing delay in acceleration and deceleration.
Table 7-21
Parameter Function Shipping set
FF
Sets the feed forward compensation gain. FF0
l The parameter FF sets the feed forward compensation gain.
l If a large parameter data is specified, overshoot may occur frequently though the tracing delay is
improved. The proper data of the FF parameter is approximately 0.5 or less in general.
Figure 7-43
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Velocity
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Position data
Position
loop gain
Feed forward
compensation gain
Velocity data
Differentiation
FF
PG