Checking The Controller Parameters - Siemens RWF55.5 User Manual

Example
Pb too small
x
w
7865d17/1099
Figure 33: Pb too small
rt, dt too small
x
w
7865d16/1099
Figure 35: rt, dt too small
Optimum adjustment
x
w
7865d18/1099
Figure 37: Optimum adjustment
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9.2 Checking the controller parameters

Optimum adjustment of the controller to the controlled system can be checked by
recording a startup sequence with the control loop closed. The following diagrams
indicate possible incorrect adjustments, and their correction.
The response to a setpoint change is shown here for a 3rd order controlled system for
a PID controller. The method used for adjusting the controller parameters can,
however, also be applied to other controlled systems. A suitable value for dt is rt/4.
t
t
t
User Manual RWF55...
9 Self-setting function
Pb too large
x
w
7865d15/1099
Figure 34: Pb too large
rt, dt too large
x
w
7865d14/1099
Figure 36: rt, dt too large
t
t
CC1U7867en
05.11.2013