Interpolation Mode - Mitsubishi Electric Melservo MR-J3-A Instruction Manual

7. GENERAL GAIN ADJUSTMENT

7.4 Interpolation mode

The interpolation mode is used to match the position loop gains of the axes when performing the interpolation
operation of servo motors of two or more axes for an X-Y table or the like. In this mode, the model loop gain
and speed loop gain which determine command track ability are set manually and the other parameter for gain
adjustment are set automatically.
(1) Parameter
(a) Automatically adjusted parameters
The following parameters are automatically adjusted by auto tuning.
Parameter No.
PB06
PB08
PB09
PB10
(b) Manually adjusted parameters
The following parameters are adjustable manually.
Parameter No.
PB07
(2) Adjustment procedure
Step
1 Set to the auto tuning mode.
During operation, increase the response level setting (parameter No. PA09), and
2
return the setting if vibration occurs.
3 Check the values of model loop gain.
4 Set the interpolation mode (parameter No. PA08: 0000).
Set the model loop gain of all the axes to be interpolated to the same value. At that
5
time, adjust to the setting value of the axis, which has the smallest model loop gain.
Looking at the interpolation characteristic and rotation status, fine-adjust the gains
6
and response level setting.
(3) Adjustment description
(a) Model loop gain (parameter No. PB07)
This parameter determines the response level of the position control loop. Increasing model loop gain
improves track ability to a position command but a too high value will make overshooting liable to occur
at the time of settling. The droop pulse value is determined by the following expression.
Droop pulse value (pulse)
Abbreviation
GD2 Ratio of load inertia moment to servo motor inertia moment
PG2 Position loop gain
VG2 Speed loop gain
VIC Speed integral compensation
Abbreviation
PG1 Model loop gain
Operation
Rotation speed (r/min)
60
Model loop gain setting
7 - 10
Name
Name
Select the auto tuning mode 1.
Adjustment in auto tuning mode 1.
Check the upper setting limits.
Select the interpolation mode.
Set model loop gain.
Fine adjustment.
262144(pulse)
Description