Disturbance Suppression Function - Mitsubishi Electric MELSEC iQ-R Series User Manual

1.35

Disturbance Suppression Function

This function quickly damps the temperature change caused by disturbance while a temperature is in a stable state.
To control the temperature fall (bottom) caused by the disturbance, execute the feed forward control (FF control). After the
bottom control, the control mode returns to the normal PID control.
The disturbance suppression function cannot be used in the position proportional control.
Set value (SV)
Disturbance
judgment position
(1)
(1) FF control
(2) PID control
Ex.
This function is good to the devices to which a disturbance periodically is generated as shown below.
• Injection molding machine
• Semiconductor manufacturing equipment (plate for heating wafers)
• Packaging machine
Disturbance has occurred!!
Set value (SV)
(1) Overshoots after the bottom control are suppressed.
(2) The temperature fall (bottom) is suppressed.
Precautions
This function uses a noise filter to avoid a false detection for the disturbance judgment. Thus, if the temperature fluctuation
caused by disturbance is steep in terms of time, the disturbance judgment may delay.
(2)
(1)
(2)
Process value (without disturbance
suppression function)
Process value (with disturbance
suppression function)
1 FUNCTIONS
1.35 Disturbance Suppression Function
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