Derivative Operation (D Operation) - Mitsubishi Electric MELSEC-Q QnPHCPU Programming Manual

1 OVERVIEW

1.4.3 Derivative operation (D operation)

This section explains the control method using the derivative operation.
(1) The derivative operation is an operation that adds the proportional manipulated value to the
change speed to eliminate deviation when a deviation has occurred.
The derivative operation can prevent large changes in the object control from disturbances.
(2) Derivative time (T
manipulated value of a derivative operation reaches that of a proportional operation.
Increasing the derivative time makes the derivative operation stronger.
(3) The derivative operation when the deviation is a constant value stepped response is shown in
Fig. 1.5.
(4) The derivative operation can be used as PD operation in combination with a proportional
operation or as a PID operation in combination with the proportional operation and integral
operation.
Control cannot be carried out by merely performing the derivative operation.
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) indicates the length of time from when a deviation occurred until the
D
DV
Time
K DV
P
T
D
Time
Fig. 1.5 Derivative operation when the deviation is a constant
Manipulated value for proportional operation
MELSEC-Q
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