Realtime Autotuning - Omron OMNUC G5 R88M-K series User Manual

10-3 Realtime Autotuning

Realtime autotuning estimates the load inertia of the machine in realtime and operates the
machine by automatically setting the gain according to the estimated load inertia. At the same
time, it can lower the resonance and vibration if operated with the adaptive filter enabled.
Refer to "10-6 Adaptive Filter" (P.10-25) for details about adaptive filters.
Realtime autotuning is enabled for any control to adjust the speed loop PI control.
Position / Speed
command
Position / Speed
Position feedback
Precautions for Correct Use
 Realtime autotuning may not function properly under the conditions described in the following
table.In such cases, use manual tuning.
Load inertia
Load
Operation
pattern
 With realtime autotuning, each parameter is fixed to the value in the machine rigidity table at the
time the machine rigidity is set. By estimating the load inertia from the operation pattern, the
operation coefficient for the speed loop gain and the integration time constant are altered. Doing
this for each pattern can cause vibration, so the estimation value is set conservatively.
OMNUC G5-Series AC Servo Drives Users Manual (Built-in MECHATROLINK-II communications type)
Friction torque
compensation
control
Estimate load
inertia.
Conditions under which realtime autotuning does not operate properly
• If the load inertia is small or large compared with the rotor inertia.
(less than 3 times, more than 20 times, or more than the applicable load inertia
ratio)
• If the load inertia changes quickly. (in less than 10 s)
• If the machine rigidity is extremely low.
• If there is backlash or play in the system.
• If the speed is continuously run at a low speed below 100 r/min.
• If the acceleration/deceleration gradually changes at less than 2,000 r/min in 1 s.
• If the acceleration/deceleration torque is too small compared with the unbalanced
load and the viscous friction torque.
• If a speed of 100 r/min or an acceleration/deceleration of 2,000 r/min/s does not
continue for at least 50 ms.
10-3 Realtime Autotuning
Torque
command
Current
control
Speed feedback
SM
Load
RE
10
10-6