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Systems and methods for urging a valve plug off a seat of a control valve and toward a set point in the absence of significant delay. Adjustable, user-selected input parameters to the input of a lead-lag filter in communication with the input of a control loop facilitates achieving tunable response

Systems and methods for urging a valve plug off a seat of a control valve and toward a set point in the absence of significant delay. Adjustable, user-selected input parameters to the input of a lead-lag filter in communication with the input of a control loop facilitates achieving tunable response by a control valve upon application of small amplitude inputs.

대표청구항 ▼

What is claimed: 1. A system for urging a valve plug off a seat of a control valve, comprising: a control loop including a valve controller, a current-to-pressure transducer, a control valve, and a valve actuator in operable communication with a valve plug of the control valve; a lead-lag filter in

What is claimed: 1. A system for urging a valve plug off a seat of a control valve, comprising: a control loop including a valve controller, a current-to-pressure transducer, a control valve, and a valve actuator in operable communication with a valve plug of the control valve; a lead-lag filter in direct communication with an input control signal to the control loop wherein the lead-lag filter provides a momentary reference control signal in response to the input control signal to overdrive the input control signal to one of a forward gain path of the control loop or the current-to-pressure transducer to produce an output signal adapted to stimulate movement of the valve plug. 2. The system of claim 1, wherein the lead-lag filter includes a programmable interface to modify the initial conditions of the lead-lag filter. 3. The system of claim 1 wherein the momentary reference control signal is generated by a switching function to provide an artificial drive signal for a predetermined duration of time. 4. The system of claim 1, wherein the programming of the lead-lag filter accepts at least one artificial initial condition and, in response to said at least one artificial initial condition, provides an output signal which compensates for a difference between the artificial initial condition and an expected initial condition by increasing the output signal. 5. A system for tuning the response of a control valve comprising: a control loop including a valve controller, a current-to-pressure transducer, a control valve, and a valve actuator in operable communication with a valve plug of the control valve; a lead-lag filter in direct communication with an input control signal to the control loop; a process controller supplying a reference control signal to an input of the lead-lag filter; and a user interface in operable communication with the lead-lag filter, said user interface including at least one adjustable interface control, wherein adjustment of each of said at least one adjustable interface controls alters at least one tuning coefficient associated with the lead-lag filter, and wherein the user interface includes a user-variable input parameter to set an initial condition to a setting resulting in an increased output of the lead-lag filter in response to a small amplitude input. 6. The system of claim 5, wherein adjustment of one of the at least one adjustable interface controls of the user interface supplies an artificial initial condition, and the lead-lag filter includes programming which causes an output signal to compensate for a difference between the artificial initial condition and an expected initial condition by increasing the output signal. 7. The system of claim 6, wherein the artificial initial condition is a negative value. 8. The system of claim 6, wherein the user-variable input parameter is selected from among a plurality of predefined input parameters. 9. A method for urging a valve plug off a seat of a control valve, comprising: providing an input control signal at an input to a control loop including a valve controller, a current-to-pressure transducer, a control valve, and a valve actuator in operable communication with a valve plug of the control valve; providing a lead-lag filter in direct communication with the input control signal; providing a user interface in operable communication with the lead-lag filter, said user interface facilitating remote manipulation of a ratio of lead-to-lag produced by the lead-lag filter; and manipulating an output of at least one of the lead-lag filter and the current-to-pressure transducer to effect movement of the valve plug to a desired level with respect to a seat of the control valve in response to a small amplitude input. 10. The method of claim 9, wherein in manipulating the output of at least one of the lead-lag filter and the current-to-pressure transducer, an adjustable interface control of the user interface supplies an artificial initial condition to an input of the lead-lag filter. 11. The method of claim 10, wherein the adjustable interface control enables selection of one of a plurality of available predefined artificial initial conditions to be supplied to the input of the lead-lag filter. 12. The method of claim 10, wherein programming associated with the lead-lag filter is executed upon the supplying of the artificial initial condition to the input of the lead-lag filter, and the programming producing an output signal of the lead-lag filter to compensate for a difference between the artificial initial condition and an expected initial condition by increasing the output signal. 13. The method of claim 10, wherein in supplying the artificial initial condition, the artificial condition corresponds to a negative value. 14. The method of claim 9, wherein in manipulating the output of at least one of the lead-lag filter and the current-to-pressure transducer, a switching function supplies an initial condition to a servo set point associated with the control valve for a predetermined duration of time. 15. The method of claim 14, wherein the predetermined duration of time is less than one second. 16. The method of claim 14, wherein the switching function provides a maximum drive of the servo set point associated with the control valve. 17. The method of claim 9, wherein in manipulating the output of at least one of the lead-lag filter and the current-to-pressure transducer, the current-to-pressure transducer is initialized to 0% for a predetermined duration of time, then powered to a nominal operating level. 18. The system of claim 1, further comprising a switch operatively coupled to one of a forward gain path of the control loop and the current-to-pressure transducer wherein the switch includes programming adapted to manipulate an artificial reference signal to produce an output signal adapted to stimulate movement of the valve plug. 19. The system of claim 18, wherein the programming of the switch includes a switching function adapted to provide the artificial control signal for a predetermined duration of time. 20. The system of claim 18, wherein the switch is provided at a summer associated with one of the forward gain path of the control loop and the current-to-pressure transducer.