Behavior models used in CIP Motion
Chapter 2
Rockwell Automation Publication MOTION-RM003I-EN-P - February 2018
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includes the motor and the load and has the effect of canceling the effects the
system inertia/mass has on control loop response and loop gain settings.
Because the torque units are expressed as % of Rated Torque of the motor, the
units for the System Inertia attribute are % Rated per Motor Units/Sec
2
.
The acceleration units can be expressed in Feedback 1 or Feedback 2 Units based
on the Feedback Mode setting. Therefore, in the case where Feedback 2 applies,
the acceleration signal needs to be scaled by the Feedback Unit Ratio as shown by
the Unit Ratio.
See also
Inertia compensation features are included in the Torque Control behavior
model.
Backlash Compensation
Backlash Compensation is used to stabilize the device control loop behavior in
applications with high load inertia ratios and mechanical backlash.
The Backlash Compensation Window attribute is used to control the Backlash
Compensation feature. Mechanical backlash is a common problem in applications
that use mechanical gearboxes. The problem stems from the fact that until the
input gear is turned to the point where its proximal tooth contacts an adjacent
tooth of the output gear, the reflected inertia of the output is not felt at the motor.
In other words, when the gear teeth are not engaged, the system inertia is reduced
to the motor inertia.
Inertia Compensation