Systems and methods for controlling exhaust gas flow in exhaust gas recirculation gas turbine systems

Patent metadata

Field	Value
Publication number	US-10012151-B2
Application number	US-201414312659-A
Country	US
Kind code	B2
Filing date	Jun 23, 2014
Priority date	Jun 28, 2013
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

A method of controlling an exhaust gas recirculation (EGR) gas turbine system includes adjusting an angle of a plurality of inlet guide vanes of an exhaust gas compressor of the EGR gas turbine system, wherein the plurality of inlet guide vanes have a first range of motion defined by a minimum angle and a maximum angle, and wherein the angle is adjusted based on one or more monitored or modeled parameters of the EGR gas turbine system. The method further includes adjusting a pitch of a plurality of blower vanes of a recycle blower disposed upstream of the exhaust gas compressor, wherein the plurality of blower vanes have a second range of motion defined by a minimum pitch and a maximum pitch, and the pitch of the plurality of blower vanes is adjusted based at least on the angle of the plurality of inlet guide vanes.

First claim

The invention claimed is:

1. An exhaust gas recirculation (EGR) gas turbine system, comprising:
an exhaust gas compressor positioned along an EGR path and configured to compress a recirculated exhaust gas only to produce an exhaust gas diluent, wherein the exhaust gas compressor comprises an inlet section comprising a flow control element comprising a plurality of inlet guide vanes configured to modulate a flow of the recirculated exhaust gas into the exhaust gas compressor based on a position of the flow control element, wherein the position of the flow control element is capable of ranging from a maximum open position to a minimum open position;
a recycle blower comprising a plurality of blower vanes positioned along the EGR path and upstream of the exhaust gas compressor and a motor, wherein the recycle blower is configured to provide the flow of recirculated exhaust gas to the inlet section, wherein the flow of recirculated exhaust gas ranges from a minimum blower output to a maximum blower output; and
a controller coupled to the flow control element and to the recycle blower, wherein the controller is configured to control the position of the flow control element based on a measured or modeled parameter of the EGR gas turbine system, wherein the controller is configured to control one or more operational parameters of the recycle blower to control the flow of recirculated exhaust gas to the inlet section based on the position of the flow control element, wherein the one or more operational parameters comprises a rotational speed of the blower controlled by the motor, a pitch of the plurality of blower vanes, or any combination thereof.

2. The EGR gas turbine system of claim 1 , wherein the controller is configured to control the one or more operational parameters of the recycle blower to control the flow of recirculated exhaust gas to the inlet section based on the position of the flow control element relative to the maximum open position.

3. The EGR gas turbine system of claim 1 , wherein the measured or modeled parameter comprises an exhaust temperature, a firing temperature, or a combination thereof, of the EGR gas turbine system.

4. The EGR gas turbine system of claim 1 , wherein the minimum open position is based on a stall limit of the exhaust gas compressor and a minimum open limit of the flow control element, and wherein the maximum open position is based on a maximum open limit of the flow control element.

5. The EGR gas turbine system of claim 1 , wherein the minimum blower output is based on a stall limit of the recycle blower, a minimum pressure limit of the recycle blower, and a minimum pressure rise limit of the recycle blower, and wherein the maximum blower output is based on a maximum pressure limit at the inlet section.

6. The EGR gas turbine system of claim 1 wherein the one or more operational parameters comprise an amount of electrical power applied to the recycle blower.

7. The EGR gas turbine system of claim 1 , comprising a turbine combustor configured to combust a fuel in the presence of an oxidant and the exhaust gas diluent at an equivalence ratio between 0.95 and 1.05.

8. The EGR gas turbine system of claim 1 , wherein the controller is configured to control the one or more operational parameters of the recycle blower to control the flow of recirculated exhaust gas to the inlet section such that the position of the flow control element generally remains at a set point position.

9. The EGR gas turbine system of claim 8 , wherein the flow control element is configured by the controller to generally remain at the set point position until the flow of exhaust gas is set to the minimum blower output or the maximum blower output by the controller.

10. The EGR gas turbine system of claim 8 , wherein the set point position is greater than 75% of a range from the minimum open position to the maximum open position.

11. The EGR gas turbine system of claim 8 , wherein the set point position is greater than 90% of a range from the minimum open position to the maximum open position.

12. A method of controlling an exhaust gas recirculation (EGR) gas turbine system, comprising:
adjusting an angle of a plurality of inlet guide vanes of an exhaust gas compressor of the EGR gas turbine system, wherein the plurality of inlet guide vanes have a first range of motion defined by a minimum angle and a maximum angle, and wherein the angle is adjusted based on one or more monitored or modeled parameters of the EGR gas turbine system; and
adjusting a pitch of a plurality of blower vanes of a recycle blower disposed upstream of the exhaust gas compressor, wherein the plurality of blower vanes have a second range of motion defined by a minimum pitch and a maximum pitch, and the pitch of the plurality of blower vanes is adjusted based at least on the angle of the plurality of inlet guide vanes.

13. The method of claim 12 , wherein adjusting the pitch of the plurality of blower vanes comprises adjusting the pitch of the plurality of blower vanes based on the angle of the plurality of inlet guide vanes relative to the minimum angle of the plurality of inlet guide vanes.

14. The method of claim 12 , wherein the plurality of parameters comprise an exhaust temperature, a firing temperature of the EGR gas turbine system, or a combination thereof.

15. The method of claim 12 , wherein the pitch of the plurality of blower vanes is adjusted based, at least in part, on a stall limit of the recycle blower, a minimum pressure limit of the recycle blower, and a minimum pressure rise limit of the recycle blower.

16. The method of claim 12 , wherein adjusting the pitch comprises adjusting the pitch to enable the angle of the plurality of inlet guide vanes to substantially remain at a set point angle.

17. The method of claim 16 , wherein the set point angle is less than 20% of the second range of motion of the plurality of inlet guide vanes from the minimum angle to the maximum angle of the plurality of inlet guide vanes.

18. The method of claim 16 , wherein the set point angle is 5% of the range of motion of the plurality of inlet guide vanes from the minimum angle to the maximum angle of the plurality of inlet guide vanes.

19. The method of claim 16 , comprising generally maintaining the angle of the plurality of inlet guide vanes at the set point angle until after the pitch of the plurality of blower vanes has been adjusted to the minimum pitch or the maximum pitch.

20. A non-transitory, computer-readable medium storing instructions executable by a processor of an electronic device, the instructions comprising:
instructions to adjust an angle of a plurality of inlet guide vanes of a compressor section of a gas turbine system based on one or more modeled or measured parameters of the gas turbine system, wherein the angle ranges from a minimum angle to a maximum angle; and
instructions to adjust a pitch of a plurality of blower vanes of a blower fluidly coupled to an inlet of the compressor section, wherein the pitch ranges from a minimum pitch to a maximum pitch, wherein the pitch is adjusted based on the angle of the plurality of inlet guide vanes relative to the minimum angle.

21. The medium of claim 20 , wherein the compressor section is a recycle compressor section and the blower is a recycle blower of an exhaust gas recirculation (EGR) turbine system.

22. The medium of claim 20 , wherein the instructions adjust the pitch of the plurality of blower vanes to maintain a headspace between the angle

Assignees

• Gen Electric
• Exxonmobil Upstream Res Co

Inventors

• Thatcher Jonathan Carl
• West James A
• Vorel Aaron Lavene

Classifications

• F02C9/54

  by throttling the working fluid, by adjusting vanes · CPC title

• F02C1/06

  using reheated exhaust gas (F02C1/08 takes precedence) · CPC title

• F01D17/141

  by means of shiftable members or valves obturating part of the flow path · CPC title

• F02C7/042

  having variable geometry · CPC title

• Y02E20/16

  Combined cycle power plant [CCPP], or combined cycle gas turbine [CCGT] · CPC title