ABB ACH550-01 User Manual page 239

ACH550 User's Manual
Code Description
2303 DERIVATION TIME
Sets the derivation time for the speed controller.
• Derivative action makes the control more responsive to 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 figure below shows the speed controller output after an error step
when the error remains constant.
K = Gain =1
p
T = Integration time > 0
I
T = Derivation time > 0
D
T = Sample time period = 2 ms
s
Δe = Error value change between two samples
K * T
p D
Parameter listing and descriptions
%
Δe
*
T
K * e
s
p
K * e
p
Range
0...10000 ms
Controller output
Error value
e = Error value
t
T
I
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