N5: Feed Forward Control - YASKAWA A1000 Technical Manual

5.9 n: Special Adjustments
 n5: Feed Forward Control
Enabling Feed Forward can improve the drives responsiveness to speed reference changes in applications where a high
speed control proportional gain setting (ASR gain, C5-01, C5-03) would lead to problems with overshoot, undershoot, or
oscillation. Figure 5.110
and the function principle are illustrated in
for induction or PM motors (A1-02 = 3 or 7), or in Advanced Open Loop Vector Control for PM motors (A1-02 = 6).
Figure 5.110
Figure 5.111
Frequency
reference after
Soft Starter
U1-16
Note: 1. Feed Forward can only be used in CLV, AOLV/PM, and CLV/PM control modes.
2. Prior to using Feed Forward, always perform Auto-Tuning or set the correct motor data manually. Also perform ASR Auto-Tuning to
set the speed loop gain (C5-01), or adjust it manually. Fine-tune the other speed control loop parameters (C5-) if required.
3. If not restricted by the application, use Inertia Auto Tuning (T1-01, T2-01 = 8) to have the drive automatically optimize Feed
Forward parameters. If Inertia Auto Tuning cannot be performed, parameters related to Feed Forward should be set manually.

n5-01: Feed Forward Control Selection
Enables to disables the Feed Forward function.
No.
n5-01
Setting 0: Disabled
Setting 1: Enabled

n5-02: Motor Acceleration Time
Sets the time required to accelerate the motor from a full stop up to the rated speed at the rated torque.
No.
n5-02
This value can be set automatically by Inertia Auto-Tuning. If Inertia Auto-Tuning cannot be performed, use one of the
methods below to determine the setting value for this parameter.
306
gives an example of overshoot reduction by Feed Forward. Parameters related to this function
Figure
1050
900
750
0
0 0.5 1
Time (s)
Conventional Speed Control
Figure 5.110 Overshoot Suppression by Feed Forward Control
Feed Forward Torque
Compensation Value
Feed Forward
Control
n5-02/03
+
Frequency
-
Reference
Speed
Feedback
Figure 5.111 Feed Forward Control
Name
Feed Forward Control Selection
Parameter Name
Motor Acceleration Time
5.111. Feed Forward can only be used in Closed Loop Vector Control
1050
Overshoot
900
750
0
0 0.5 1
Time (s)
Feed Forward Control
Feed Forward Output
U6-26
+
ASR P and I
C5-01/02/03/04
U6-25
ASR Output
YASKAWA ELECTRIC SIEP C710616 27G YASKAWA AC Drive A1000 Technical Manual
Suppresses
overshoot at the
end of acceleration
ASR Delay and
Torque reference
+
Torque Limits
C5-06, L7-
U1-09
Setting Range
0 or 1
Setting Range
0.001 to 10.000 s
Default
0
Default
Determined by C6-01,
E5-01 and o2-04