Mitsubishi Electric MELSERVO-J3W Series Instruction Manual page 121

6. GENERAL GAIN ADJUSTMENT
6.2.2 Auto tuning mode basis
The block diagram of real-time auto tuning is shown below.
Parameter No.PA08 Parameter No.PA09
0 0 0
Gain adjustment mode
selection
When a servo motor is accelerated/decelerated, the load inertia moment ratio estimation section always
estimates the load inertia moment ratio from the current and speed of the servo motor. The results of estimation
are written to parameter No.PB06 (the ratio of load inertia moment to servo motor). These results can be
confirmed on the status display screen of the MR Configurator.
If the value of the load inertia moment ratio is already known or if estimation cannot be made properly, choose
the "auto tuning mode 2" (parameter No.PA08: 0002) to stop the estimation of the load inertia moment ratio
(Switch in above diagram turned off), and set the load inertia moment ratio (parameter No.PB06) manually.
From the preset load inertia moment ratio (parameter No.PB06) value and response level (parameter No.PA09),
the optimum loop gains are automatically set on the basis of the internal gain tale.
The auto tuning results are saved in the EEP-ROM of the servo amplifier every 60 minutes since power-on. At
power-on, auto tuning is performed with the value of each loop gain saved in the EEP-ROM being used as a
factory setting.
Loop gains
Command
PG1,VG1
PG2,VG2,VIC
Gain
table
Response
setting
POINT
If sudden disturbance torque is imposed during operation, the estimation of the
inertia moment ratio may malfunction temporarily. In such a case, choose the "auto
tuning mode 2" (parameter No.PA08: 0002) and set the correct load inertia
moment ratio in parameter No.PB06.
When any of the auto tuning mode 1 and auto tuning mode settings is changed to
the manual mode 2 setting, the current loop gains and load inertia moment ratio
estimation value are saved in the EEP-ROM.
Automatic setting
Real-time auto
Set 0 or 1 to turn on.
tuning section
Switch
Parameter No.PB06
Load inertia moment
ratio estimation value
6 - 4
Current
control
Current feedback
Load inertia
moment ratio
estimation section
Speed feedback
Load inertia
moment
Encoder
Servo
motor
Position/speed
feedback