Mitsubishi Electric MELSERVO MR-J3 A Series, Instruction Manual

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7. GENERAL GAIN ADJUSTMENT
7.2 Auto tuning
7.2.1 Auto tuning mode
The servo amplifier has a real-time auto tuning function which estimates the machine characteristic (load
inertia moment ratio) in real time and automatically sets the optimum gains according to that value. This
function permits ease of gain adjustment of the servo amplifier.
(1) Auto tuning mode 1
The servo amplifier is factory-set to the auto tuning mode 1.
In this mode, the load inertia moment ratio of a machine is always estimated to set the optimum gains
automatically.
The following parameters are automatically adjusted in the auto tuning mode 1.
Parameter No. Abbreviation Name
PB06 GD2 Ratio of load inertia moment to servo motor inertia moment
PB07 PG1 Model loop gain
PB08 PG2 Position loop gain
PB09 VG2 Speed loop gain
PB10 VIC Speed integral compensation
POINT
The auto tuning mode 1 may not be performed properly if the following conditions
are not satisfied.
Time to reach 2000r/min is the acceleration/deceleration time constant of 5s or less.
Speed is 150r/min or higher.
The ratio of load inertia moment to servo motor inertia moment is 100 times or
less.
The acceleration/deceleration torque is 10% or more of the rated torque.
Under operating conditions which will impose sudden disturbance torque during
acceleration/deceleration or on a machine which is extremely loose, auto tuning
may not function properly, either. In such cases, use the auto tuning mode 2 or
manual mode to make gain adjustment.
(2) Auto tuning mode 2
Use the auto tuning mode 2 when proper gain adjustment cannot be made by auto tuning mode 1. Since
the load inertia moment ratio is not estimated in this mode, set the value of a correct load inertia moment
ratio (parameter No. PB06).
The following parameters are automatically adjusted in the auto tuning mode 2.
Parameter No. Abbreviation Name
PB07 PG1 Model loop gain
PB08 PG2 Position loop gain
PB09 VG2 Speed loop gain
PB10 VIC Speed integral compensation