PID Configuration of Minimum Flow Controller for Centrifugal Pump


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For Centrifugal Pump PID minimum flow controller, is there a special way of configuring it different from normal PID flow controller? As in minimum flow controller, we need the valve not to open until the flow become less than the setpoint. While in normal flow controller, the flow control valve can be open even if flow is less than SP. So is there a special algorithm or configuration for minimum flow controller?
No just PID but the min flow loop needs enough gain to get the recirc valve open within the time delay on the min flow pump trip when there is a big flow decrease, i.e. boiler trip.

Valve tuning or characterization may also be required to get the recir valve open quickly enough.

Smart positioners can be set to quick opening to get min flow established faster.

Your normal flow is well above the min flow setpoint, so that error will in time close the valve using gain and reset action.