Mitsubishi Electric MELSERVO MRJ2S-B, Instruction Manual

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Operation Gain
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4.6.3 Auto tuning
The servo amplifier is equipped with a real-time auto tuning function that constantly optimises the
gain factors of the control loops depending on the machine characteristics (inertia of mass ratio).
This allows time-consuming settings during start-up to be avoided.
Auto tuning 1
The servo amplifier is factory-set to the auto tuning mode 1. In this mode, the inertia 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:
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 is not more than 100times.
●
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 1 or
2 to make gain adjustment.
Auto tuning 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 this value in parameter
No. 12
The following parameters are automatically adjusted in the auto tuning mode 2:
Parameter Symbol Name
12 GD2
Ratio of load inertia moment to servo motor inertia
moment
13 PG1 Position control gain 1
14 VG1 Speed control gain 1
15 PG2 Position control gain 2
16 VG2 Speed control gain 2
17 VIC Speed intergral compensation
Tab. 4-16: Parameter adjusted in the auto tuning mode 1
Parameter Symbol Name
13 PG1 Position control gain 1
14 VG1 Speed control gain 1
15 PG2 Position control gain 2
16 VG2 Speed control gain 2
17 VIC Speed intergral compensation
Tab. 4-17: Parameter adjusted in the auto tuning mode 2