User manual

10 Functions and operations in the speed control mode
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4.
Decrease the deviation that cannot be adjusted with the speed loop gain. Set the application
parameter for speed loop integral time constant [APP-0-05].
If the integral time constant is too high, motor operation will become slow. If the constant is too low, on
the other hand, hunting may occur.
5.
When the parameter for operation selection after stopping in speed control mode [SyS-1-02] is
set to “Servo lock,” adjust the compliance with respect to position deviation. Set the application
parameter for position loop gain [APP-0-03].
Increasing the position loop gain will decrease the deviation between the command position and actual
position. Note, however, that an excessively high value may increase the motor overshoot or cause
hunting.
6.
Repeat steps 2 to 5 to set an optimal gain.
• Speed feed-forward rate
This parameter can be set when the parameter for operation selection after stopping in speed control mode
[SyS-1-02] is set to “Servo lock.”
If the speed is constant, the deviation between the command position and actual position can be reduced to
shorten the settling time.
Setting the speed feed-forward rate to 100% will bring the deviation down to nearly 0. Note, however, that an
excessively high value may increase the motor overshoot or undershoot.
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Gains that can be set with automatic tuning/semi-auto tuning
In automatic tuning and semi-auto tuning, the gain is set automatically.
The table below summarizes different conditions and corresponding gains.
SW2 dial
setting
Value of mechanical
rigidity setting switch
parameter
Position
loop gain
[Hz]
Speed loop
gain [Hz]
Speed loop
integral time
constant [ms]
Speed
feed-forward
rate [%]
0 0 3 14 51.0 80
1 1 4 22 51.0 80
2 2 6 32 48.2 80
3 3 9 46 33.8 80
4 4 11 56 28.4 80
5 5 14 68 23.4 80
6 6 16 82 19.4 80
7 7 20 100 15.8 80
8 8 20 120 13.2 80
9 9 20 150 10.6 80
A 10 20 180 8.8 80
B 11 20 220 7.2 80
C 12 20 270 5.8 80
D 13 20 330 4.8 80
E 14 20 390 4.0 80
F 15 20 470 3.4 80