Mitsubishi Electric MELSERVO MR-J4-B-LL Series Instruction Manual page 68

4. PRESSURE LOOP GAIN ADJUSTMENT
(2) Adjustment of the proportional control gain (pressure loop gain)
First, set [Pr. PT01], [Pr. PT02], and [Pr. PT03] as follows in order to enable only the proportional control
gain.
Next, increase the value of [Pr. PT01] gradually with a constant value of the pressure command is being
input from the controller. If a vibration occurs, decrease the value slightly. As a rough guide, set [Pr.
PT01] to 70% to 80% of the value generated the vibration.
If this satisfies the required performance, setting the integral control gain is not necessary.
The following shows the relation between the setting value of the proportional control gain (pressure
loop gain) and the response performance.
[Pr. PT01 Pressure control gain]
High
Low
Small
Setting value of [Pr. PT01]
Changing [Pr. PT22 Pressure feedback unit constant] also changes the response performance of the
pressure control. In this case, readjust the pressure loop gain.
For example, if the value of [Pr. PT22] is doubled, it works the same as the pressure control proportional
gain of [Pr. PT01 Pressure loop gain] is doubled. When the response performance of the pressure
control needs to be unchanged, change the setting value of [Pr. PT01] to "(the value of [Pr. PT22] before
change)/(the value of [Pr. PT22] after change)", and check the operation.
(3) Adjustment of the integral control gain (pressure integral compensation and pressure incomplete integral
coefficient)
If the result of the proportional control gain adjustment does not satisfy the required performance, adjust
the integral control gain.
The integral control gain adjustment differs depending on the machine configuration. Adjust the gain by
following (a) or (b) which suits your machine.
"A machine providing a constant pressure when the servo motor stops" refers to a machine pressing
together with a constant pressure by using the pressure control. "A machine providing a constant
pressure when the servo motor rotates" refers to a machine pushing out with a constant pressure by
using the pressure control.
Parameter Symbol
PT01 APA
PT02
PT03 ADA
Pressure command
Large
Increasing the setting value of [Pr. PT01] improves track ability to the command.
A too large setting value will generate vibration.
Set "10".
AIA Set "1000".
Set "0".
Increasing the setting value of [Pr. PT01]
4 - 5
Setting
Pressure feedback
Time