Pid Dancer Roll Control - Siemens MICROMASTER 440 Operating Instructions Manual

Issue 10/06
3.11.1.3

PID dancer roll control

For various continuous production processes, e.g. in the paper and pulp industry,
or in the manufacture of cables, it is necessary to control (closed-loop) the velocity
of stations along the production process so that the continuous material web is not
subject to any inadmissible tension levels. It is also important that no folds or
creases are formed. For applications such as these, it is practical to provide a type
of material buffer in the form of a loop with a defined tension. This provides a de-
coupling between the individual drive locations. This loop represents the difference
between the material fed-in and that fed-out and therefore indicates the process
quality.
Using the PID dancer roll control, with MICROMASTER 440 it is possible to ensure
that continuous material webs have a constant tension.
v *
2
x *
2
x
2
Fig. 3-57
The velocity v
should be controlled using drive rolls A
corresponds, as far as possible, to the setpoint.
The structure and important parameters for the PID dancer roll control are listed in
Fig. 3-58 and Table 3-27.
MICROMASTER 440 Operating Instructions
6SE6400-5AW00-0BP0
v
2
x
2
SUM
setpoint
PID PID
PID
setpoint RFG
−
PID
feedback
PID dancer roll control
is assumed to be an independent disturbance; the input velocity v
1
v
1
AFM RFG
PID
limit
so that the length x
2
3 Functions
Motor
control
2
of the loop
2
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