The current minor loop regulator, 2 the current minor loop regulator – Rockwell Automation WebPak 3000 DC Drive Application Workbook Version 1.1 User Manual
Page 32
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4-4
WebPak 3000 DC Drive Application Workbook, Version 1.1
Note the following design features:
•
Network logic will switch between current and speed regulation by activating bit 11
of the network command word.
•
If a network kit is installed, the control source is
NETWORK
, and P.811 is set to
DISABLE
, the drive will operate according to the status of jumper J15.
•
If a network kit is not installed, drive operation will revert back to the status of jumper
J15, ignoring the status of P.811.
NETWORK
KIT
(P.796) indicates if a network kit is
INSTALLED
or
NOT
INSTALLED
.
•
Speed loop and current minor loop self-tuning can only be performed when the
control source is
TERMBLK
. Jumper J15 must be set to the speed/voltage position to
perform speed loop self-tuning.
•
Section jog cannot be used when current/torque is active. The current/speed
network bit must be set to speed to permit section jog. If a jog-to-run transition
occurs, the drive will run in the mode specified by the current/speed network bit.
This will permit switching “on the fly” from a speed-regulated jog mode to a
current/torque regulator.
•
The
S
-
CURVE
block and the speed loop
PI
block are conditioned to permit a smooth
transition from torque to speed by network bit switching.
•
In the current/torque mode, a stop command will initiate a coast/DB stop.
•
In the speed/voltage mode, a stop command will initiate a stop as defined by
STOP
MODE
SELECT
(P.114).
Important: The WebPak 3000 drive does not accommodate bumpless dynamic
switching of other types of outer control loop designs.
4.2
The Current Minor Loop Regulator
Refer to figure A.9 in Appendix A of the software manual (D2-3444) as you configure
the current minor loop (
CML
) regulator.
The proportional-integral (
PI
) controller adjusts the armature power bridge firing angle,
ARMATURE
DELTA
(P.399), to compensate for any difference between the reference
CML
REFERENCE
(P.396) and the feedback
CML
FEEDBACK
(P.397).
ARMATURE
BRIDGE
POL
(P.394) indicates which armature power bridge is active.
OFF
indicates the forward bridge.
ON
indicates the reverse bridge.
CML
FEEDBACK
(P.397) is scaled by
CML
FEEDBACK
GAIN
ADJ
(P.300), J18
ARM
I
FB
RESISTOR
(P.395),
MOTOR
RATED
ARM
AMPS
(P.008), and
CT
TURNS
RATIO
(P.010). These
parameters can be validated for the connected motor by using information found in the
WebPak 3000 software manual (D2-3444).
þ
To configure the current minor loop regulator:
▲
Set or verify
CML
FEEDBACK
GAIN
ADJ
(P.300).
Range: 0.900 to 1.100
P.300 =