Automatic Setting Of Control Parameters - Siemens SIPART DR22 Manual

4 Commissioning

4.5 Automatic setting of control parameters

4.5 Automatic setting of control parameters
by the adaptation method
The adaptation method should always be preferred to manual settings because the control
results with the parameters gained from adaptation are better especially in slow controlled
systems and this saves optimization time.
D Presetting
-- S58 selecting the control behavior (structuring mode Strs)
No adaptation is possible when S58 = 0. In position 1 a control behavior without
overshoot is offered. In position 2 changes in the command variables can be expected
with a maximum 5 % overshoot.
-- tU: Monitoring time (parameterization mode AdAP)
tU is necessary for error messages only and has no influence on the identification quality.
tU must be set at least double the transient recovery time T
you have little knowledge of the controlled system, use tU = oFF (factory setting) for
adapting. After successful adaptation tU is automatically set to 2T
At tU < 0.1 h (6 min) tU = oFF is displayed.
-- dPv: Direction of the step command (parameterization mode AdAP)
The direction of the controlled variable change from the set operating point is selected
with this configuring switch: x
batches it is recommendable to perform one adaptation with rising x and one with falling
x. The averaged or dynamically more uncritical parameters can then be used for the con-
trol.
-- dy: Amplitude of the step command (parameterization mode AdAP)
The step command must be selected so great that the controlled variable changes by at
least 4 % and the controlled variable change must be 5 times the average noise level.
The greater the controlled variable change, the better the identification quality. Controlled
variable changes of approx. 10 % are recommended.
D Notes on certain types of control for pre-adaptation
-- Cascade control
Double controllers are always adapted to the controller selected by the Shift key (12). In
cascade controls the sequence controller is adapted first in manual operation by selecting
the controller I with the Shift key (12). We recommend you to use the controller version
without overshoot (S58=1) so that the command behavior is uncritical. Then the master
controller is adapted in internal and automatic mode of the follow-up controller. To do this,
switch the folow-up controller to Internal on selecting the controller I (corresponds to
manual operation of the master controller) and switch over to automatic operation, set the
desired operating point by changing the setpoint if necessary. Then switch over to
controller II (master controller) with the Shift key and start adaptation. The setpoint step
of the follow-up controller is invisible for system identification.
220
±∆x = ±ks (y
manual manual
of the controlled system. If
95
.
95
±∆y). In controlled systems with
SIPART DR22 6DR2210
C79000-G7476-C154-03
Manual