YASKAWA SGD7S series Product Manual page 140

7.1 Parameter Adjustments for Predictive Control
7.1.4 Adjustment Methods
3.
After the arc reduction is mostly eliminated, check for overshooting.
During cutting feed feeding, check the position deviation near where the motor stops.
If there is overshooting that is greater than the required specifications, increase the predictive control
speed feedforward gain (Pn154) by 10 at a time and measure the amount of overshooting. Excessive
overshooting tends to cause arc radius reduction.
Note: When you adjust the predictive control, the value of the Pn153 (Predictive Control Equivalent Ratio) must
7-4
be the same for all shafts. Differences in values may result in the distortion illustrated in the following fig-
ure.