Gas turbine combustor control system for stoichiometric combustion in the presence of a diluent

Patent metadata

Field	Value
Publication number	US-10107495-B2
Application number	US-201314066551-A
Country	US
Kind code	B2
Filing date	Oct 29, 2013
Priority date	Nov 2, 2012
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

In one embodiment, a gas turbine system includes a controller configured to receive fuel composition information related to a fuel used for combustion in a turbine combustor; receive oxidant composition information related to an oxidant used for combustion in the turbine combustor; receive oxidant flow information related to a flow of the oxidant to the turbine combustor; determine a stoichiometric fuel-to-oxidant ratio based at least on the fuel composition information and the oxidant composition information; and generate a control signal for input to a fuel flow control system configured to control a flow of the fuel to the turbine combustor based on the oxidant flow information, a target equivalence ratio, and the stoichiometric fuel-to-oxidant ratio to enable combustion at the target equivalence ratio in the presence of an exhaust diluent within the turbine combustor.

First claim

The invention claimed is:

1. A non-transitory, computer-readable medium comprising computer-executable instructions which when executed are configured to cause a processor to:
receive fuel composition information related to a fuel used for combustion in a turbine combustor of a gas turbine system;
receive oxidant composition information related to an oxidant used for combustion in the turbine combustor of the gas turbine system;
receive oxidant flow information related to a flow of the oxidant to the turbine combustor;
determine a stoichiometric fuel-to-oxidant ratio (FOR ST ) based at least on the fuel composition information and the oxidant composition information;
generate a control signal for input to a fuel flow control system configured to control a flow of the fuel to the turbine combustor using both a feed forward component and a feedback component to enable combustion at the target equivalence ratio in the presence of an exhaust gas diluent;
adjust a fuel flow control valve of the fuel flow control system based on the control signal, wherein the control signal is configured to increase a flow of the fuel to the turbine combustor when the feedback component, or the feed forward component, or both are a positive value;
wherein the feed forward component is based on the oxidant flow information, a target equivalence ratio, and FOR ST ; and
wherein the feedback component comprises a measured equivalence ratio determined based at least in part on an emissions model output and a lambda sensor output, the emissions model output is based on feedback from one or more exhaust sensors indicative of exhaust composition information of an exhaust gas generated from combustion products from the turbine combustor, and the one or more exhaust sensors comprises a hydrogen sensor or a carbon monoxide sensor.

2. A gas turbine system, comprising:
a turbine combustor configured to combust a fuel and an oxidant at a target equivalence ratio in the presence of an exhaust diluent to produce combustion products;
an oxidant path configured to deliver the oxidant to the turbine combustor at an oxidant flow rate;
a fuel path configured to deliver the fuel to the turbine combustor at a fuel flow rate, wherein the fuel path comprises a fuel flow control system configured to adjust the fuel flow rate in response to one or more control signals;
an exhaust compressor driven by a shaft of the gas turbine system, wherein the exhaust compressor is configured to receive and compress only an exhaust gas generated from the combustion products and to direct the exhaust diluent to the turbine combustor;
a controller communicatively coupled to the fuel flow control system, wherein the controller comprises:
one or more non-transitory, machine readable media collectively storing one or more sets of instructions; and
one or more processing devices configured to execute the one or more sets of instructions to provide the one or more control signals to the fuel flow control system, wherein a fuel flow control valve of the fuel flow control system is adjusted based on the one or more control signals to adjust the fuel flow rate to the turbine combustor to enable combustion in the turbine combustor at the target equivalence ratio, wherein the one or more control signals comprise a feedback component and a feed forward component, wherein the feed forward component is based on the oxidant flow rate, a target equivalence ratio, and a stoichiometric fuel-to-oxidant ratio (FOR ST ), wherein the feedback component comprises a measured equivalence ratio determined based at least in part on an emissions model output and a lambda sensor output, wherein the emissions model output is based on feedback from one or more exhaust sensors indicative of exhaust composition information of an exhaust gas generated from combustion products from the turbine combustor, wherein the one or more exhaust sensors comprises a hydrogen sensor or a carbon monoxide sensor, wherein the control signal is configured to reduce a flow of the fuel to the turbine combustor when the feedback component, or the feed forward component, or both are a negative value; and

an oxygen sensor disposed along the oxidant path, wherein the oxygen sensor is communicatively coupled to the controller, and the oxygen sensor is configured to determine oxidant composition information.

3. The gas turbine system of claim 2 , comprising
an exhaust flow path configured to flow the exhaust gas generated from the combustion products produced within the turbine combustor, wherein the exhaust flow path comprises:
a turbine configured to extract work from the combustion products to drive the shaft of the gas turbine system and generate the exhaust gas;
the exhaust compressor; and
the one or more exhaust sensors, wherein the one or more exhaust sensors is disposed along the exhaust flow path between the turbine and the exhaust compressor, and wherein the one or more exhaust sensors are communicatively coupled to the controller.

4. The gas turbine system of claim 2 , wherein the feedback component is configured to adjust the fuel flow rate to the turbine combustor to account for drift and variations in the fuel flow rate.

5. The gas turbine system of claim 2 , comprising an exhaust extraction flow path coupled to the turbine combustor, wherein the exhaust extraction flow path is configured to flow at least a portion of the exhaust gas from the turbine combustor to an enhanced oil recovery (EOR) system as an extracted exhaust gas.

6. The gas turbine system of claim 5 , comprising:
an exhaust extraction flow meter disposed along the exhaust extraction flow path, wherein the exhaust extraction flow meter is communicatively coupled to the controller, and the exhaust extraction flow meter is configured to determine flow information relating to the extracted exhaust gas from the turbine combustor; and
an exhaust extraction flow control valve disposed along the exhaust extraction flow path, wherein the exhaust extraction flow control valve is communicatively coupled to the controller, and the exhaust extraction flow control valve is configured to at least partially adjust an amount of the extracted exhaust gas from the turbine combustor.

7. The gas turbine system of claim 2 , wherein an emissions model is configured to generate the emissions model output, and wherein the emissions model comprises a physics-based model, a computational fluid dynamics model, a finite element analysis model, an artificial intelligence model, a statistical model, or any combination thereof.

8. A gas turbine system comprising:
a controller, comprising:
one or more tangible, non-transitory, machine-readable media collectively storing one or more sets of instructions; and
one or more processing devices configured to execute the one or more sets of instructions to:
receive fuel composition information related to a fuel used for combustion in a turbine combustor of the gas turbine system;
receive oxidant composition information related to an oxidant used for combustion in the turbine combustor of the gas turbine system;
receive oxidant flow information related to a flow of the oxidant to the turbine combustor;
determine a stoichiometric fuel-to-oxidant ratio (FOR ST ) based at least on the fuel composition information and the oxidant composition information;
generate a control signal for input to a fuel flow control system configured to control a flow of the fuel to the turbine combustor using both a feed forward component and a feedback component to enable combustion at the target equivalence ratio in the presence of an exhaust gas diluent, wherein the feed forward component is based on the oxidant flow information, a target equivalence ratio, and FOR ST , and wherein t

Assignees

• Gen Electric
• Exxonmobil Upstream Res Co

Inventors

• Minto Karl Dean

Classifications

• F23N2223/36

  PID signal processing · CPC title

• F23N2221/10

  Analysing fuel properties, e.g. density, calorific · CPC title

• F23N2241/20

  Gas turbines · CPC title

• F23N5/18 Primary

  using detectors sensitive to rate of flow of air or fuel · CPC title

• F02C1/08

  Semi-closed cycles · CPC title