Rockwell Automation 7000 PowerFlex Medium Voltage (B Frame) Commissioning - ForGe (PanelView 550) User Manual
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Rockwell Automation Publication 7000-IN006B-EN-P - May 2013
Chapter 5 Commissioning the Drive
4. Set parameter CurReg Bandwidth in Current Control to 100 rad/sec. A
lower than the normal bandwidth makes the step response easier to
measure.
5. Set parameter T DC Link in Current Control to 0.020 sec, which is at the
low end of the normal range of values and should produce an under-
damped response.
6. Assign parameters Idc Reference and Idc Feedback in the Current Control
group to 2 DPM test points e.g. RTP1 and RTP2. This process is similar to
the meter assignments described earlier. Use an oscilloscope to view the
results.
7. Start the drive. Set parameter Idc Ref Step in Current Control to 0.075pu
for AFE rectifier drive and 0.200 pu for SCR drives. The dc link current
will step up and down by this amount at regular intervals.
8. Adjust the scope to trigger on the rising edge of the dc current reference
and observe the dc current feedback on the other channel. The step
response may have noticeable overshoot, indicating that the dc link time
constant is too low.
9. Adjust the T DC Link parameter until the current feedback rises to ~63%
of its final value in 10 ms as shown in
. The
overshoot should reasonably small. Increasing T DC Link causes the rise
time to increase. Since the desired step response is slightly under-damped,
do not increase the T DC Link beyond the value at which the overshoot
disappears.
Figure 55 - Current regulator tuned incorrectly
Idc Reference
Idc Feedback
63%
0%
Idc Reference
Idc Feedback
63%
0%