Rockwell Automation 20G PowerFlex 750-Series AC Drives - Manual (Page 193)

Rockwell Automation Publication 750-RM002B-EN-P - September 2013 193
Diagnostics and Protection Chapter 3
The responsiveness to an impact load can be adjusted with P622 [Slip Comp
BW]. However, too high setting can cause unstable operation and overshoot.
Baking Line Application Example
The diagram below shows a typical application for the slip compensation feature.
The PLC controls the frequency reference for all four of the drives. Drive No. 1
and Drive No. 3 control the speed of the belt conveyor. Slip compensation is used
to maintain the RPM independent of load changes caused by the cutter or dough
feed. By maintaining the required RPM, the baking time remains constant and
therefore the end product is consistent.
Impact Load
Applied
Impact Load
Removed
Increasing Slip
Comp Gain
Increasing Slip
Comp Gain
Time
Spe
ed
Rotor Speed
Reference
0
0
Dough Stress
Relief Cookie Line
Drive
No. 1 Drive
No. 2 Drive
No. 3 Drive
No. 4
Cutters Oven
PLC