Mitsubishi Electric MR-J2-03B5, Instruction Manual

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6. ADJUSTMENT
6.4.4 When shortening the settling time
(1) Machine condition
The settling time will be increased by the gains provided by auto tuning.
(2) Adjustment procedure
1) Select the response setting of slow response.
Set parameter No. 8 to "0001" and parameter No. 9 to "0003" or less.
2) Alternate a start and a stop several times, execute auto tuning, and check whether the machine
does not vibrate.
3) Set the load inertia moment ratio (parameter No. 12).
If an exact load inertia moment ratio is unknown, enter an approximate value.
When the value is set in this parameter, the following parameters are set automatically. When
there is no machine resonance, the value of each parameter is set to the ideal gain for the load
inertia moment ratio (parameter No. 12) value.
Parameter No. Symbol Name
13 PG1 Position loop gain 1
15 PG2 Position loop gain 2
14 VG1 Speed loop gain 1
16 VG2 Speed loop gain 2
17 VIC Speed integral compensation
4) Set "not executed" (parameter No. 8: 0002) by the auto tuning selection.
Make the parameter No. 13 to 17 settings manually adjustable.
5) Check the operating status and adjust the following parameter values:
Parameter No. Symbol Name Description
13 PG1 Position loop gain 1
15 PG2 Position loop gain 2
Higher setting shortens the settling time but
is liable to cause overshooting.
14 VG1 Speed loop gain 1
16 VG2 Speed loop gain 2
Higher setting improves the servo response
level but is liable to cause vibration.
17 VIC Speed integral compensation
Lower setting keeps the speed constant to
load disturbance and increases holding force
at a stop (servo rigidity) but is liable to
cause overshooting.
Make adjustment by gradually increasing the parameter No. 13 to 16 settings at the same ratio and
reducing the speed integral compensation (parameter No. 17). The optimum value is provided at the point
just before vibration increases. Use of the notch filter (parameter No. 18) may increase the limit point.
However, note that the setting increased up to the limit point may cause resonance due to the machine's
variations and changes with time.