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6. GENERAL GAIN ADJUSTMENT
(b) Adjustment procedure
Step
Operation
Description
1
Brief-adjust with auto tuning. Refer to section 6.3.3.
2
Change the setting of auto tuning to the manual mode (Parameter No.PA08:
003).
3
Set an estimated value to the load to motor inertia moment ratio. (If the
estimate value with auto tuning is correct, setting change is not required.)
4
Set a slightly smaller value to the model loop gain and the position loop gain.
Set a slightly larger value to the speed integral compensation.
5
Increase the speed loop gain within the vibration- and unusual noise-free
range, and return slightly if vibration takes place.
Increase the speed loop gain.
6
Decrease the speed integral compensation within the vibration-free range,
and return slightly if vibration takes place.
Decrease the time constant of the speed
integral compensation.
7
Increase the position loop gain, and return slightly if vibration takes place.
Increase the position loop gain.
8
Increase the model loop gain, and return slightly if overshooting takes place.
Increase the model loop gain.
9
If the gains cannot be increased due to mechanical system resonance or the
like and the desired response cannot be achieved, response may be
increased by suppressing resonance with adaptive tuning mode or machine
resonance suppression filter and then executing steps 3 to 8.
Suppression of machine resonance.
(Refer to section 7.2.)
10
While checking the settling characteristic and rotational status, fine-adjust
each gain.
Fine adjustment
(c) Adjustment description
1) Speed loop gain (VG2: parameter No. PB09)
The same as for the internal speed control.
2) Speed integral compensation (VIC: parameter No. PB10)
The same as for the internal speed control.
3) Position loop gain (PG2: parameter No. PB08)
This parameter determines the response level to the disturbance of the position control loop.
Increasing position loop gain decreases the change at external disturbance. If the gain is too high;
however, overshooting is likely to occur when settling.
4) Model loop gain (PG1: parameter No. PB07)
This parameter determines the response level of the model loop. Increasing position loop gain 1
improves track ability to a position command but a too high value will make overshooting liable to
occur at the time of settling.