Mitsubishi Electric MELSERVO MR-J4-B-LL Series, Instruction Manual

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4. PRESSURE LOOP GAIN ADJUSTMENT
4 - 7
(b) For a machine providing a constant pressure when the servo motor rotates
First, set [Pr. PT01], [Pr. PT02], and [Pr. PT03] as follows.
Parameter Symbol Setting
PT01 APA Set the result of (2) adjustment of the proportional control gain (pressure
loop gain)
PT02 AIA Set "500".
PT03 ADA Set "10000".
Next, if an overshoot or a vibration occurs when [Pr. PT03] is set to "10000", decrease the value of
[Pr. PT03] until the overshoot or the vibration stops.
Then, decrease the value of [Pr. PT02] gradually. If an overshoot or a vibration occurs, increase the
value slightly.
The following shows the relation between the setting value of the integral control gain (pressure
integral compensation and pressure incomplete integral coefficient) and the response performance.
[Pr. PT03 Pressure incomplete integral coefficient]
Setting value of [Pr. PT03]
Large
Low
High
Small
Time
If the setting value of [Pr. PT03] is small, the pressure does not reach to the command.
A too large setting value will generate overshoot.
Response
Pressure
Pressure command
Pressure feedback
Increasing the setting value of [Pr. PT03]
[Pr. PT02 Pressure integral compensation]
Pressure command
Pressure feedback
Decreasing the setting value of [Pr. PT02]
Decreasing the setting value of [Pr. PT02] improves track ability to the command.
A too small setting value will generate overshoot or vibration.
Setting value of [Pr. PT02]
Large
Low
High
Small
Time
Response
Pressure
4.6 Checking of adjustment result
After adjusting the pressure loop gain, check the operation by executing the pressure control cycle operation
with the actual operation patterns. When there is no problem, the pressure control adjustment is complete. If
a vibration occurs, execute "4.5 Adjustment of pressure loop gain" again.