Rockwell Automation WebPak 3000 DC Drive Application Workbook Version 1.1 - Manual (Page 49)

Configuring Losses Compensation 8-1
C
HAPTER
8
Configuring Losses Compensation
When a current regulator is used to control tension or to support load share profiling,
its performance will be enhanced by the application of friction and windage loss
compensation. These losses vary with line speed/motor speed; therefore,
FRICTION
LOSS (P.123) and WINDAGE LOSS (P.243), which are set based on machine dynamics
such as bearing loads and gearbox loads, will be modified as a function of speed.
Line speed is normalized by applying SPD SOURCE SELECT OUT (P.193) and TOP LINE
SPEED (P.020) to a multiplier block. The block output is multiplied by NORM ROLL DIA
(P.131) to convert it to a rotational speed.
The speed-modified values of P.123 and P.243 are scaled, summed and set
proportional to motor field amps based on the value of
NORM FIELD REF (P.130).
This composite signal is identified as LOSSES COMPENSATION (P.316). Refer to figure
A.15 in Appendix A of the software manual (D2-3444) as you configure losses
compensation.
þ
To configure the losses compensation function:
▲
Set FRICTION LOSS (P.123).
▲
Set WINDAGE LOSS (P.243).
þ
To calibrate the losses compensation function:
▲
Tune the speed loop with its connected load. If the load is variable diameter,
use empty core diameter.
Use This Chapter for These Applications:
•
Constant Diameter Speed Regulator
•
Variable Diameter Speed Regulator
•
Constant Diameter Current Regulator
• Variable Diameter Current Regulator
• Variable Diameter Position Regulator
• Constant Diameter Tension Regulator
• Variable Diameter Tension Regulator
• Generic
Range: 0.0 to 50.0% P.123 = %
Range: 0.0 to 50.0% P.243 = %