System and method for controlling and diagnosing a combined cycle power plant

• US 9,547,294 B2
• Filed: 05/18/2012
• Issued: 01/17/2017
• Est. Priority Date: 05/18/2012
• Status: Active Grant

• Current Assignee: Faro Technologies Incorporated, GE Infrastructure Technology, LLC (GE Vernova, Inc.)
• Original Assignee: General Electric Company
• Inventors: Osmundsen, Mark Robert, Seely, William Forrester, Sholes, John Edward, Tillery, Steven William
• Primary Examiner(s): Charioui, Mohamed
• Assistant Examiner(s): RASTOVSKI, CATHERINE T
• Application Number:
  US13/475,201
• Publication Number:
  US 20130311139A1
• Time in Patent Office: 1,705 Days
• Field of Search: 702/182, 702/183
• US Class Current: 1/1
• CPC Class Codes: G05B 17/02 electric
• CPC Class Codes: Y02E 20/16 Combined cycle power plant [CCPP], or combined cycle gas turbine [CCGT]

Abstract

A system and method in a combined cycle power plant includes a processor modeling plant level performance by considering the interrelation between outputs of the gas turbine and the steam turbine. The model can be computational, predictive, or both. The model may be used to control subsystems of the plant (including the gas turbine and the steam turbine) to achieve a target plant performance. The model may also be used to diagnose or maintain subsystems of the combined cycle power plant.

Claims

1. A system in a combined cycle power plant, the system comprising:

a measurement device configured to measure one or more parameters of plant subsystems, the plant subsystems including a gas turbine and a steam turbine, wherein the one or more parameters comprise a gas turbine inlet guide van angle, a steam turbine rotor stress, a steam turbine eccentricity, and a steam turbine case temperature;

a model processor comprising a physics-based model configured to provide a model output of plant performance based on the one or more parameters, the model processor considering an interconnection between outputs of the gas turbine and the steam turbine of the combined cycle power plant;

a user input device configured to receive a desired steam turbine steam pressure from a user;

a target performance determination unit configured to determine a target plant performance based at least on the desired steam turbine steam pressure; and

a controller configured to control operation of the gas turbine based on the model output to achieve the target plant performance.

2. The system according to claim 1, further comprising:

a processor configured to diagnose one or more of the plant subsystems based on the model output.

3. The system according to claim 2, wherein the processor diagnoses the one or more plant subsystems based on a comparison of the model output with a range of acceptable values.

4. The system according to claim 3, wherein

the processor diagnoses a malfunction of the one or more subsystems based on a first range of acceptable values, and

the processor diagnoses a maintenance state for the one or more subsystems based on a second range of acceptable values.

5. The system according to claim 4, wherein a user determines the first range of acceptable values and the second range of acceptable values.

6. The system according to claim 4, wherein the first range of acceptable values and the second range of acceptable values are predetermined.

7. The system according to claim 4, wherein an output device displays an alert when the processor diagnoses the malfunction or the maintenance state.

8. The system according to claim 1, wherein the model processor executes a computational model.

9. The system according to claim 1, wherein the model processor executes a predictive model.

10. The system according to claim 1, wherein the target performance determination unit is a storage device that stores predetermined values of target plant performance.

11. The system according to claim 1, wherein the target performance determination unit includes the user input device.

12. A method of diagnosing subsystems of a combined cycle power plant, the method comprising:

measuring one or more parameters of plant subsystems, the plant subsystem including a gas turbine and a steam turbine, wherein the one or more parameters comprise a gas turbine inlet guide van angle, a steam turbine rotor stress, a steam turbine eccentricity, and a steam turbine case temperature;

modeling plant performance via a physics-based model based on the one or more parameters, the modeling being based on an interconnection between outputs of the gas turbine and the steam turbine of the combined cycle power plant;

receiving a user input comprising a desired steam turbine steam pressure from a user;

determining target plant performance based at least on the desired steam turbine steam pressure;

diagnosing a malfunction of one or more of the plant subsystems based on the modeled plant performance; and

controlling the one or more of the plant subsystems based on the diagnosing and on the target plant performance.

13. The method according to claim 12, wherein the diagnosing includes comparing the modeled plant performance with a range of acceptable values.

14. The method according to claim 13, further comprising:

diagnosing the malfunction of the one or more of the plant subsystems based on a first range of acceptable values; and

diagnosing a maintenance state for the one or more plant subsystems based on a second range of acceptable values.

15. The method according to claim 14, further comprising:

accepting a user input of the first range of acceptable values and the second range of acceptable values.

16. The method according to claim 14, further comprising:

obtaining the first range of acceptable values and the second range of acceptable values from a storage device.

17. A method of controlling performance of a combined cycle power plant, the method comprising:

measuring one or more parameters of plant subsystems, the plant subsystems including a gas turbine and a steam turbine, wherein the one or more parameters comprise a gas turbine inlet guide van angle, a steam turbine rotor stress, a steam turbine eccentricity, and a steam turbine case temperature;

modeling plant performance via a physics-based model based on the one or more parameters, the modeling being based on an interconnection between outputs of the gas turbine and the steam turbine of the combined cycle power plant;

receiving a user input comprising a desired steam turbine steam pressure from a user;

determining target plant performance based at least on the desired steam turbine steam pressure; and

controlling the gas turbine based on the modeled plant performance to achieve the target plant performance.

18. The method according to claim 17, wherein the determining target plant performance includes accessing stored plant performance values in a storage device.

19. The method according to claim 17, wherein the determining target plant performance includes receiving a user input.