Rockwell Automation 9329 Drive Application Software Tension Control Gen. Units - Manual (Page 46)

FM – Tension Control
Drive Application Software – page 46 of 52
6.5 Tension Regulator
6.5.1 Trimming Speed:
The TrimLimSpd_Pct is the maximum output of the trim regulator and is based on the
maximum line speed. This value should typically be 5 to 10 percent. When the line
speed is zero the TrimLimSpdZero_Pct is the maximum output of the trim regulator.
This value is typically set for 1 to 2 percent. This allows the trim regulator to operate
even though the line velocity is at zero.
There is not a simple formula for calculating the starting gains for tension regulation.
The user should start by setting the TrimFB_wld and TrimFb_wlg equal to each other.
This will cancel the effect of the feedback lead lag filter.
Begin the tuning process by increasing TrimKP until the system becomes oscillatory.
Once the system becomes oscillatory, you will need to reduce TrimKP to 70% of the
value. After TrimKP is set adjust Trim_Wld until the steady state performance is
satisfactory.
6.5.2 Trimming Torque
When the tension regulator is trimming torque, the TrimLimTrq_Pct is set typically for
10 to 20 percent.
The user should start by setting the TrimFB_wld and TrimFb_wlg equal to each other.
This will cancel the effect of the feedback lead lag filter.
Begin the tuning process by setting the Trim_wld term to zero. Increase the TrimKP
term until the system appears to oscillate and then reduce the TrimKP by 50%. At
this point, there will be a steady state error. Adjust Trim_wld to decrease the steady
state error. Begin decreasing the TrimFB_wld from 10 to 5 to 1 until the desired
response is achieved.