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7. GENERAL GAIN ADJUSTMENT
7.2.2 Auto tuning mode operation
The block diagram of real-time auto tuning is shown below.
Motor
7010
SW1
Command
Automatic setting
Control gains
PG1,VG1
PG2,VG2,VIC
Current
control
Current feedback
Load inertia
moment
Encoder
Position/speed
feedback
Real-time auto
tuning section
Speed feedback
Load inertia
moment ratio
estimation section
Gain
table
Parameter No. 2
Third digit
Auto tuning selection
First digit
Response level setting
Parameter No. 34
Load inertia moment
ratio estimation value
Set 0 or 1 to turn on.
When a motor is accelerated/decele rated, the load inertia moment ratio estimation section always
estimates the load inertia moment ratio from the current and speed of the motor. The results of
estimation are written to parameter No. 34 (load inertia moment ratio). These results can be confirmed on
the status display screen of the servo amplifier display section.
If the value of the load inertia moment ratio is already known or if estimation cannot be made properly,
set " 2 " in parameter No. 2 (auto tuning) to stop th e estimation o f the load iner tia moment ratio
(SW1 in above diagram turned off), and set the load inertia moment ratio in parameter No. 34 manually.
From the value of parameter No. 34 and the first digit (r esponse level set ting) of parame ter No. 2, the
optimum control gains are automat ically set on the basis of the inte rnal gain table.
The auto tuning results are saved in the EEP-ROM 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 EEP-ROM being
used as an initial value.
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. 2: 020 ) and set the correct
load inertia moment ratio in parameter No. 34.