Mitsubishi Electronics MR-J2S- CL Auto tuning mode operation, General Gain Adjustment, Point

8. GENERAL GAIN ADJUSTMENT

8.2.2 Auto tuning mode operation

The block diagram of real-time auto tuning is shown below.

	Automatic setting
Command	Control gains		Current
	PG1,VG1		control
	PG2,VG2,VIC
		Current feedback
	Set 0 or 1 to turn on.	Real-time auto
		tuning section

Load inertia moment

Encoder

Servo motor

Position/speed feedback

Gain table

Parameter No. 3

First digit

Third digit Response level setting Auto tuning selection

Load inertia

moment ratio

Switch estimation section Speed feedback

Parameter No. 34 Load inertia moment ratio estimation value

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. 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,

chose the "auto tuning mode 2" (parameter No.3: 2 ) 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. 34) manually.

From the preset load inertia moment ratio (parameter No. 34) value and response level (The first digit of parameter No. 2), the optimum control 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 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. 3: 020) and set the correct load inertia moment ratio in parameter No. 34.

When any of the auto tuning mode 1, auto tuning mode 2 and manual mode 1 settings is changed to the manual mode 2 setting, the current control gains and load inertia moment ratio estimation value are saved in the EEP-ROM.

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