About the differences between complete derivative and incomplete derivative
■[Incomplete derivative]
Incomplete derivative is PID control that has a primary delay filter in the input of a derivative term.
The S.PIDCONT instruction is the incomplete derivative PID control instruction.
Incomplete derivative is effective for the following cases.
• Control susceptible to high-frequency noise
• When energy effective to actuate an operation end is not given when a step change occurs in a complete derivative system
■[Complete derivative]
Complete derivative is PID control that uses the input of a derivative term as it is.
The PIDCONT instruction is the complete derivative PID control instruction.
PID operation
The control method when proportional operation (P operation), integral operation (I operation), and derivative operation (D
operation) are used in combination is described below.
• During PID operation, the system is controlled by the MV (manipulated value) calculated in the (P + I + D) operation.
• PID operation in step response with a constant E (deviation) is illustrated below.
4 FUNCTIONS OF PID CONTROL
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4.2 Functions of PID Control