Mitsubishi Electric FR-A800, Instruction Manual

Page: 361 / 1042

Parameters Position control under vector control and PM sensorless vector control
FR-A800 5 - 181
5.5.9 Position control gain adjustment
Easy gain tuning is provided as an easy tuning method. For details about easy gain tuning, refer to
page 5-67.
If it does not produce any effect, make fine adjustment by using the following parameters.
Set "0" to Pr. 819 "Easy gain tuning selection" before setting the following parameters.
Position control gain (Pr. 422, Pr. 1298)
●
Make adjustment when any of such a phenomena as unusual vibration, noise and overcurrent of
the motor/machine occurs.
●
Increasing the setting improves traceability for the position command and also improves servo
rigidity at a stop, but oppositely makes an overshoot and vibration more liable to occur.
●
Normally set this parameter within the range about 5 to 50.
Pr. Name Initial value Setting range Description
422
B003
Position control gain
25 s
-1
0 to 150 s
-1
Set the gain for the position loop.
1298
B013
Second position control
gain
25 s
-1
0 to 150 s
-1
Set the position loop gain for the second motor.
423
B004
Position feed forward gain 0% 0 to 100%
Function to cancel a delay caused by the droop
pulses in the deviation counter.
425
B006
Position feed forward
command filter
0 s 0 to 5 s
Input the first delay filter for the feed forward
command.
446
B012
Model position control
gain
25 s
-1
0 to 150 s
-1
Set the gain for the model position controller.
828
G224
Model speed control gain 60% 0 to 1000% Set the gain for the model speed controller.
877
G220
Speed feed forward
control/model adaptive
speed control selection
0
0, 1 Perform position feed forward control.
2 Model adaptive position control becomes valid.
880
C114
Load inertia ratio 7-fold 0 to 200-fold Set the load inertia ratio for the motor.
Movement

condition How to adjust Pr. 422
Response is slow.
Increase the setting value.
Increase the setting value by 3 s
-1
until immediately before an overshoot, stop-time
vibration or other instable phenomenon occurs, and set about 80 to 90% of that value.
Overshoot, stop-time vibration
or other instable phenomenon
occurs.
Lower the setting value.
Lower the setting value by 3 s
-1
until immediately before an overshoot, stop-time
vibration or other instable phenomenon does not occur, and set about 80 to 90% of that
value.
Tab. 5-68: Setting of parameter 422
Vector Vector Vector PM PM PM