초록 ▼

A coordinated air-fuel controller and associated method provide a fuel controller, a combustion air controller and a steady-state air versus fuel model. The fuel controller generates a fuel control output signal and the combustion air controller generates a combustion air control output signal. The

A coordinated air-fuel controller and associated method provide a fuel controller, a combustion air controller and a steady-state air versus fuel model. The fuel controller generates a fuel control output signal and the combustion air controller generates a combustion air control output signal. The fuel controller determines a preliminary fuel control signal based on at least one of first and second loop control signals, and determines the fuel control output signal based on the preliminary fuel control signal. The steady-state air versus fuel model processes the preliminary fuel control signal to determine an expected steady-state combustion air control signal. The combustion air controller determines a preliminary combustion air control signal based on at least one of a third loop control signal and a fourth loop control signal, and determines the combustion air control output signal based on the preliminary combustion air control signal and the expected steady-state combustion air control signal.

대표청구항 ▼

1. A control system for a gas turbine, including: a fuel control actuator;a combustion air control actuator;a coordinated air-fuel controller that controls operations of the fuel control actuator and the combustion air control actuator, wherein the coordinated air-fuel controller receives a pluralit

1. A control system for a gas turbine, including: a fuel control actuator;a combustion air control actuator;a coordinated air-fuel controller that controls operations of the fuel control actuator and the combustion air control actuator, wherein the coordinated air-fuel controller receives a plurality of gas turbine condition input signals and determines, based on the input signals, a first error signal, a second error signal, a third error signal and a fourth error signal, and wherein the coordinated air-fuel controller includes: a fuel controller that provides a fuel control output signal to the fuel control actuator to control operations of the fuel control actuator, wherein the fuel controller processes the first error signal using a first transfer function to obtain a first loop control signal,wherein the fuel controller processes the second error signal using a second transfer function to obtain a second loop control signal, andwherein the fuel controller determines a preliminary fuel control signal based on at least one of the first loop control signal and the second loop control signal, and determines the fuel control output signal based on the preliminary fuel control signal;a combustion air controller that provides a combustion air control output signal to the combustion air control actuator to control operations of the combustion air control actuator; anda cross-channel controller in communication with the fuel controller, wherein the cross-channel controller processes the preliminary fuel control signal according to an air versus fuel model, to determine an expected steady-state combustion air control signal;wherein the combustion air controller processes the third error signal using a third transfer function to obtain a third loop control signal,wherein the combustion air controller processes the fourth error signal using a fourth transfer function to obtain a fourth loop control signal, andwherein the combustion air controller determines a preliminary combustion air control signal based on at least one of the third loop control signal and the fourth loop control signal, and determines the combustion air control output signal based on the preliminary combustion air control signal and the expected steady-state combustion air control signal. 2. The control system of claim 1, wherein the coordinated air-fuel controller includes a bounds calculator for determining upper and lower bounds applied to the preliminary combustion air control signal, wherein the bounds calculator determines the upper and lower bounds based on a rate of change of the expected steady-state combustion air control signal. 3. The control system of claim 1, wherein the air versus fuel model is automatically adjusted, removing a difference between the combustion air control output signal and the expected steady-state combustion air control signal. 4. The control system of claim 1, wherein at least some of the gas turbine condition input signals are based on estimated conditions. 5. The control system of claim 1, wherein at least some of the gas turbine condition input signals are provided by sensors associated with the gas turbine. 6. The control system of claim 5, wherein said sensors associated with the gas turbine include a speed sensor that senses a rotational speed of the gas turbine and generates a speed signal, and a temperature sensor that senses exhaust temperature of the gas turbine and generates a temperature signal. 7. The control system of claim 1, wherein the fuel controller includes an actuator dynamics compensator that compensates for response characteristic differences between the fuel control actuator and the combustion air control actuator, and wherein the actuator dynamics compensator processes the preliminary fuel control signal to determine the fuel control output signal. 8. The control system of claim 7, wherein, in determining the fuel control output signal, the actuator dynamics compensator adds a delay to the preliminary fuel control signal. 9. The control system of claim 1, wherein the fuel control output signal is equal to the preliminary fuel control signal. 10. The control system of claim 1, wherein the combustion air controller includes an actuator dynamics compensator that compensates for response characteristic differences between the fuel control actuator and the combustion air control actuator. 11. The control system of claim 1, wherein the combustion air control actuator controls a position of an inlet guide vane. 12. The control system of claim 11, wherein the fuel control actuator controls a fuel stroke, and further wherein the air versus fuel model provides a steady-state relationship between a fuel stroke reference and the position of the inlet guide vane. 13. A method of controlling air supply and fuel supply in a gas turbine, including the steps of: generating a first error signal based on a first condition of the gas turbine;generating a second error signal based on a second condition of the gas turbine;generating a third error signal based on a third condition of the gas turbine;generating a fourth error signal based on a fourth sensed condition of the gas turbine;processing the first error signal according to a first transfer function to obtain a first loop control signal;processing the second error signal according to a second transfer function to obtain a second loop control signal;processing the third error signal according to a third transfer function to obtain a third loop control signal;processing the fourth error signal according to a fourth transfer function to obtain a fourth loop control signal;generating a preliminary fuel control signal based on at least one of the first loop control signal and the second loop control signal;generating a fuel control output signal based on the preliminary fuel control signal;providing the fuel control output signal to a fuel control actuator;adjusting, by the fuel control actuator, a fuel flow based on the fuel control output signal;providing a cross-channel controller;generating, by the cross-channel controller, using an air versus fuel model, and from the preliminary fuel control signal, an expected steady-state combustion air control signal;generating a preliminary combustion air control signal based on at least one of the third loop control signal and the fourth loop control signal;generating a combustion air control output signal based on the preliminary combustion air control signal and the expected steady-state combustion air control signal;providing the combustion air control output signal to a combustion air control actuator; andadjusting, by the combustion air control actuator, an amount of combustion air based on the combustion air control output signal. 14. The method of claim 13, further comprising the step of automatically adjusting the air versus fuel model, thereby removing a difference between the combustion air control output signal and the expected steady-state combustion air control signal. 15. The method of claim 13, wherein at least one of the first condition, the second condition, the third condition and the fourth condition is an estimated condition. 16. The method of claim 13, wherein at least one of the first condition, the second condition, the third condition and the fourth condition is a sensed condition from a sensor. 17. The method of claim 13, further comprising the step of compensating for response characteristic differences between the fuel control actuator and the combustion air control actuator. 18. The method of claim 17, wherein the step of compensating for response characteristic differences between the fuel control actuator and the combustion air control actuator includes adding a delay to the preliminary fuel control signal. 19. The method of claim 13, wherein the fuel control output signal is equal to the preliminary fuel control signal. 20. The method of claim 13, further comprising the steps of: determining a rate of change of the expected steady-state combustion air control signal;calculating upper and lower bounds based on the rate of change of the expected steady-state combustion air control signal; andapplying the upper and lower bounds to the preliminary combustion air control signal. 21. The method of claim 13, wherein at least one of the first condition and the second condition is a rotational speed of the gas turbine, and wherein at least one of the third condition and the fourth condition is an exhaust temperature of the gas turbine. 22. The method of claim 13, wherein the step of adjusting, by the combustion air control actuator, the amount of combustion air includes adjusting a position of an inlet guide vane. 23. The method of claim 22, wherein the step of adjusting, by the fuel control actuator, the fuel flow includes adjusting a fuel stroke, and further wherein the air versus fuel model provides a steady-state relationship between a fuel stroke reference and the position of the inlet guide vane.