Gain Adjustment Of Position Control (Pr. 422, Pr. 423, Pr. 425) - Mitsubishi Electric FR-A760 Series Instruction Manual

4.6.6

Gain adjustment of position control (Pr. 422, Pr. 423, Pr. 425)

Easy gain tuning is available as an easy tuning method. Refer to page 91 for easy gain tuning.
If it does not produce any effect, make fine adjustment by using the following parameters.
Set "0" in Pr. 819 Easy gain tuning selection before setting the parameters below.
Parameter
Name
Number
422 Position loop gain
423 Position feed forward gain
Position feed forward
425
command filter
The above parameters can be set when the FR-A7AP (option) is mounted.
(1) Position loop gain (Pr. 422 )
⋅ Make adjustment when any of such phenomena as unusual vibration, noise and overcurrent of the motor/machine
occurs.
⋅ Increasing the setting improves trackability 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.
Phenomenon/Condition
Slow response
Overshoot, stop-time
vibration or other instable
phenomenon occurs.
(2) Position feed forward gain (Pr. 423 )
⋅ This function is designed to cancel a delay caused by the droop pulses of the deviation counter.
⋅ When a tracking delay for command pulses poses a problem, increase the setting gradually and use this parameter
within the range where an overshoot or vibration will not occur.
⋅ This function has no effects on servo rigidity at a stop.
⋅ Normally set this parameter to 0.
Initial Value
-1
25s
0%
0s
Increase the Pr. 422 value.
Increase the value 3s
Pr. 422
other instable phenomenon occurs, and set about 0.8 to 0.9 of that value.
Decrease the Pr. 422 value.
Decrease the value 3s
Pr. 422
other instable phenomenon does not occur, and set about 0.8 to 0.9 of that value.
Position control by vector control
Setting
Range
-1
Set the gain of the position loop.
0 to 150s
Function to cancel a delay caused by the droop
0 to 100%
pulses of the deviation counter.
Enters the primary delay filter in response to the
0 to 5s
feed forward command.
Adjustment Method
-1 -1
by 3s until just before an overshoot, stop-time vibration or
-1 -1
by 3s until just before an overshoot, stop-time vibration or
Vector Vector Vector
Description
127
4