Mitsubishi Electric MELSERVO MRJ2S-B Instruction Manual page 113

Gain
Auto tuning mode operation
The block diagram of real-time auto tuning is shown below:
Parameter No. 8
0
Fig. 4-6: Block diagram of auto tuning
When a servo motor is accelerated/decelerated, the inertia ratio estimation section always
estimates it from the current and speed of the servo motor. The results of estimation are written
to parameter No. 12. These results can be confirmed on the status display screen of setup-
software.
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. 8: 0003) and set the load inertia
moment ratio (parameter No. 12) manually.
From the preset load inertia moment ratio (parameter No. 12) value and response level
(parameter No. 9), the optimum control gains are automatically set on the basis of the internal
gain table.
The auto tuning results are saved in the E²PROM of the servo amplifier every 6 minutes since
power-on. At power-on, auto tuning is performed with the value of each control gain saved in the
E²PROM being used as an initial value.
NOTE
If sudden disturbance torque is imposed during operation, the estimation of the inertia ratio
may malfunction temporarily. In such a case, choose the "auto tuning mode 2" (parameter
No. 8: 0003) and set the correct load inertia moment ratio in parameter No. 12.
MELSERVO J2-Super
Control gain
+
PG1, VG1, PG2,
Command
-
VG2, VIC
Parameter No. 9
0 0 1 0 0 0 5
Response level
Auto tuning
Automatic
setting
+
-
Current feedback
Set 0 or 1 to turn on
Real-time auto tuning
Gain
table
S1
Pr. 12:
Mass inertia
ratio
Load inertia
moment
Current Servo
control motor
Position/speed
feedback
section
Mass inertia
ratio
estimation
Operation
Encoder
S000987C
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