ABB ACS150 User Manual page 8

6
Parameters
Index Name/Selection
40 PROCESS PID SET 1
4001 GAIN
0.1...100.0
4002 INTEGRATION TIME
0.0...3600.0 s
4003 DERIVATION TIME
0.0...10.0 s
4004 PID DERIV FILTER
Update notice
Description
Process PID (PID1) control parameter set 1.
Defines the gain for the process PID controller. High gain may cause speed
oscillation.
Gain. When value is set to 0.1, the PID controller output changes one-tenth
as much as the error value. When value is set to 100, the PID controller
output changes one hundred times as much as the error value.
Defines the integration time for the process PID1 controller. The integration
time defines the rate at which the controller output changes when the error
value is constant. The shorter the integration time, the faster the continuous
error value is corrected. Too short an integration time makes the control
unstable.
A
B
D (4001 = 10)
C (4001 = 1)
Integration time. If parameter value is set to zero, integration (I-part of the
PID controller) is disabled.
Defines the derivation time for the process PID controller. Derivative action
boosts the controller output if the error value changes. The longer the
derivation time, the more the speed controller output is boosted during the
change. If the derivation time is set to zero, the controller works as a PI
controller, otherwise as a PID controller.
The derivation makes the control more responsive for disturbances.
The derivative is filtered with a 1-pole filter. Filter time constant is defined by
parameter 4004 PID DERIV FILTER.
Error
100%
0%
PID output
Gain
4001
Derivation time. If parameter value is set to zero, the derivative part of the
PID controller is disabled.
Defines the filter time constant for the derivative part of the process PID
controller. Increasing the filter time smooths the derivative and reduces
noise.
A = Error
B = Error value step
C = Controller output with gain = 1
D = Controller output with gain = 10
t
4002
Process error value
t
D-part of controller output
t
4003
Def
1
60.0 s
0.0 s
1.0 s