PMA KS 98, Manual

Page: 185 / 246

24.9 Controller characteristics and self-tuning with PIDMA
As opposed to CONTR and CONTR+, the PIDMA includes a modified parallel controller
structure, which is taken into account in the following additional parameters.
Additional parameters for PIDMA
Parameter Beschreibung Wertebereich
PType Process type (a-priori information)
1: with
compensation
2: without
A.(integral)
Drift
Drift compensation des Istwertes zu Beginn der
Selbstoptimierung
0: off
1: on
CSpeed Required control loop dynamics
1: slow
2: normal
3:fast
Tpause
Minimum positioning step time (stepping controller)
0,1...999999[s ]
thron
Switch-on threshold for OPEN and CLOSE (stepping
controller)
0,2...100 %
throff
Switch-off threshold for OPEN and CLOSE (stepping
controller)
0,2...100 %
Xlimit
Switch-off point for output step change (process value
change)
0,5...999999
Tdrift Time window for process value drift determination 0...999999
Tnoise Time window for process value noise determination
0...999999
Kp
Control gain (replaces Xp1;/Xp2 of CONTR )
0,001...999,9 [%]
VD
Derivative gain (Td/T1)
1...999999
bW_p
Setpoint weighting factor of proportional action
0...1
cW_d Setpoint weighting factor of D action 0...1
Tsat Time constant for I action in Y limiting (anti-reset wind-up)
1...999999
xsh
Neutrale Zone, in dem der I-Teilfestgehalten wird
0 … 9 99999
Three point stepping(Yp)
:
Tpause , thron and throff complete the effective parameters for stepping motor control.
Tpause permits adjustment of the minimum pause in addition to minimum pulse limiting by means of Tpuls.
thron and throff define a deviation of the actuator position from an internal setting (position feedback required) from
which a pulse to the actuator is output or canceled. In connection with Xsh, these parameters can be used to influence
the actuator switching frequency and fine adjustment. Xsh determines the neutral zone of control deviation in the mas-
ter controller. Within this zone, the controller I action is held.
With setting 3-point stepping Yp (three-point stepping with position feedback, the PIDMA function block comprises two
controllers: the master controller controls the process value and provides a required actuator position to an integrated
position controller). By means of the position feedback, this position controller ensures that the actuator goes to the re-
quired position.
Self-tuning:
PType, Drift, Cspeed, Xlimit, Tdrift and Tnoise complete parameter dYopt which is also effective with CONTR. These
parameters define the conditions during self-tuning.
Ptype determines, if the process is without compensation (the new process value after a correcting variable pulse is
higher, e.g. level of a container without outlet or well- insulated furnace). An even decrease or increase of the process
value before self-tuning can be detected by means of
drift monitoring and taken into account when self-tuning is done
for the next time.
CSpeed can be used to determine if, during subsequent operation, the controller should reach the setpoint quickly,
with a slight overshoot, or slowly with gentle approach to the setpoint. Using CSpeed , the parameter can be
switched over also after self-tuning, provided that the controller parameters were not changed manually.
9499 040 50611
Controller
185 Controller characteristics and self-tuning with PIDMA