Patent ID: 7593802

Claim:
A system for tuning the position of a valve plug of a control valve within a control valve servo control loop, comprising: a control valve servo control loop including an input, a first summer in communication with the input, an amplifier in communication with the first summer, a second summer in communication with the amplifier, a control valve actuation stage in communication with the amplifier, the control valve actuation stage comprising at least a current-to-pressure transducer and a pneumatic relay in communication with the current-to-pressure transducer, the control valve actuation stage further including at least one of a group of a quick exhaust valve and a volume booster in pneumatic communication with the current-to-pressure transducer, and an actuator in communication with the control valve actuation stage and being operatively coupled to the control valve, the control valve having a valve stem operatively coupled to the valve plug, a lead-lag filter connected to the input of the process control loop; and a reference control signal applied to an input of the lead-lag input filter, the lead-lag filter selectively modifying the reference control signal to provide a filtered output of the lead-lag input filter.