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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 g ains 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 momen t ratio of a machine is always est imated to set the optimum gains
automatically.
The following parameters are automatically adjusted in the auto tuning mode 1.
Parameter No. Abbreviation Name
6PG1Position control gain 1
34 GD2 Ratio of load inertia moment to servo motor inertia moment
35 PG2 Posit ion control gain 2
36 VG1 Speed control gain 1
37 VG2 Speed control gain 2
38 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 2000rpm is the acceleration/deceleration time constant of 5s or
less.
Speed is 150r/min or higher.
The ratio of load inertia moment to motor inertia moment is not more
than 100 times.
The acceleration/deceleration torque is 10% or more of the rated torque.
Under operating conditions which will impose sudden disturban ce 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 in parameter No. 34.
The following parameters are automatically adjusted in the auto tuning mode 2.
Parameter No. Abbreviation Name
6PG1Position control gain 1
35 PG2 Posit ion control gain 2
36 VG1 Speed control gain 1
37 VG2 Speed control gain 2
38 VIC Speed integral compensation