Rockwell Automation WebPak 3000 DC Drive Application Workbook Version 1.1 - Manual (Page 73)

Configuring the Tension Outer Control Loop 12-5
12.1.4 Dynamic Gain Profiling (Variable Diameter Applications)
It is recommended that all variable diameter tension applications use dynamic gain
profiling.The gain profiler calculates the dynamic value for the
PI block proportional
gain parameter TEN PI KP OUT (P.879). Refer to figure A.19 in Appendix A of the
software manual (D2-3444).
þ
To configure dynamic gain profiling:
▲ Set TEN PROFILER ENABLE (P.878) to ENABLE .
▲ Set OCL TYPE (P.818) to select the profiling block for cascade or parallel
operation. The choices are:
CASCADE - The inputs to the profiling block are:
•
TEN PI PROP GAIN (P.841) as determined in the step response test.
•
NORM FIELD REF (P.130)
•
NORM ROLL DIAMETER (P.131)
•
SPEED PI KP OUT (P.251)
•
TEN PI LEAD FREQ (P.840) as determined in the step response test.
PARALLEL - The inputs to the profiling block are:
•
TEN PI PROP GAIN (P.841) as determined in the step response test.
•
NORM FIELD REF (P.130)
•
NORM ROLL DIAMETER (P.131)
12.2 The Tension PI Output
Refer to figure A.19 in Appendix A of the software manual (D2-3444) as you configure
the tension
PI output.
The output of the PI block is TENSION VERNIER (P.856), which is used as a trim signal on
the speed loop when CASCADE is selected or as the input to the speed loop current
limits when PARALLEL is selected as configured by OCL TYPE (P.818).
The amount of speed loop trim is set by the HI and LO limits of the PI block, TENSION PI
LIMIT (P.853), which would nominally be configured at 409 counts (10%). However,
product characteristics, such as modulus of elasticity, can require more or less than
10% trim.
Note that TENSION VERNIER (P.856) will be a proportional or incremental trim of line
speed dependent on the configuration of OCL PROP TRIM GAIN (P.812). Refer to section
3.3 and figure 3.1.
Range: ENABLE , DISABLE P.878 = (1$%/(
Range: CASCADE , PARALLEL P.818 =