Power generation system having compressor creating excess air flow and turbo-expander using same

Patent metadata

Field	Value
Publication number	US-10024197-B2
Application number	US-201514662851-A
Country	US
Kind code	B2
Filing date	Mar 19, 2015
Priority date	Mar 19, 2015
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

A power generation system may include a generator, and a gas turbine system for powering the generator, the gas turbine system including a turbine component, an integral compressor and a combustor to which air from the integral compressor and fuel are supplied, the combustor arranged to supply hot combustion gases to the turbine component, and the integral compressor having a flow capacity greater than an intake capacity of at least one of the combustor and the turbine component, creating an excess air flow. A turbo-expander may also power the generator. A first control valve control flow of the excess air flow along an excess air flow path to an inlet of the turbo-expander. An educator may be positioned in the excess air flow path for using the excess air flow as a motive force to augment the excess air flow with additional air. A discharge of the turbo-expander is supplied to an inlet of the integral compressor.

First claim

What is claimed is:

1. A power generation system, comprising:
a generator;
a gas turbine system for powering the generator, the gas turbine system including a turbine component, an integral compressor and a combustor to which air from the integral compressor and fuel are supplied, the combustor arranged to supply hot combustion gases to the turbine component, and the integral compressor having a flow capacity greater than an intake capacity of at least one of the combustor and the turbine component, creating an excess air flow;
a turbo-expander for powering the generator;
an eductor positioned in an excess air flow path upstream of the turbo-expander for using the excess air flow as a motive force to augment the excess air flow with ambient air, the eductor including a suction side flow path fluidly coupled to an inlet filter of the integral compressor;
a first control valve system controlling flow of the excess air flow along the excess air flow path to the eductor, wherein an augmented excess air flow is supplied to an inlet of the turbo-expander from the eductor,
wherein a discharge of the turbo-expander is supplied to an inlet of the integral compressor, and wherein a temperature of the discharge of the turbo-expander is less than a temperature of the ambient air, and
a second control valve system positioned in the suction side flow path and controlling a flow of the ambient air into the eductor, the flow of the ambient air distinct from the excess air flow;
a controller electronically coupled to the first control valve system and the second control valve system, and configured to adjust the first control valve system and the second control valve system to adjust the excess air flow and the flow of ambient air.

2. The power generation system of claim 1 , wherein an exhaust of the turbine component feeds a heat recovery steam generator (HRSG) for creating steam for a steam turbine system.

3. The power generation system of claim 2 , wherein the HRSG also feeds steam to a co-generation steam load.

4. The power generation system of claim 1 , wherein the first control valve system that includes a compressor discharge control valve controlling a first portion of the excess air flow taken from a discharge of the integral compressor, and an upstream control valve controlling a second portion of the excess air flow taken from a stage of the integral compressor upstream from the discharge.

5. The power generation system of claim 4 , further comprising at least one sensor for measuring a flow rate of the first portion and the second portion of the excess air flow, each sensor operably coupled to a respective control valve of the first control valve system.

6. The power generation system of claim 1 , further comprising a sensor for measuring a flow rate of an additional air in the suction side flow path, the sensor operably coupled to the second control valve system.

7. A power generation system, comprising:
a generator;
a gas turbine system for powering the generator, the gas turbine system including a turbine component, an integral compressor and a combustor to which air from the integral compressor and fuel are supplied, the combustor arranged to supply hot combustion gases to the turbine component, and the integral compressor having a flow capacity greater than an intake capacity of at least one of the combustor and the turbine component, creating an excess air flow;
a turbo-expander for powering the generator;
an eductor positioned in an excess air flow path upstream of the turbo-expander for using the excess air flow as a motive force to augment the excess air flow with ambient air, the eductor including a suction side flow path fluidly coupled to an inlet filter of the integral compressor;
a first control valve system controlling flow of the excess air flow along the excess air flow path to the eductor, wherein an augmented excess air flow is supplied to an inlet of the turbo-expander from the eductor;
a second control valve system positioned in the suction side flow path and controlling a flow of the ambient air into the eductor, the flow of the ambient air distinct from the excess air flow;
a controller electronically coupled to the first control valve system and the second control valve system, and configured to adjust the first control valve system and the second control valve system to adjust the flow of the excess air and the flow of ambient air; and
wherein a discharge of the turbo-expander is supplied to an inlet of the integral compressor, and wherein a temperature of the discharge of the turbo-expander is less than a temperature of the ambient air.

8. The power generation system of claim 7 , wherein an exhaust of the turbine component feeds a heat recovery steam generator (HRSG) for creating steam for a steam turbine system.

9. The power generation system of claim 8 , wherein the HRSG also feeds steam to a co-generation steam load.

10. The power generation system of claim 7 , wherein the first control valve system includes a compressor discharge control valve controlling a first portion of the excess air flow taken from a discharge of the integral compressor, and an upstream control valve controlling a second portion of the excess air flow taken from a stage of the integral compressor upstream from the discharge.

11. A method, comprising:
powering a generator using a gas turbine system including a turbine component, an integral compressor and a combustor to which air from the integral compressor and fuel are supplied, the combustor arranged to supply hot combustion gases to the turbine component, and the integral compressor having a flow capacity greater than an intake capacity of at least one of the combustor and the turbine component, creating an excess air flow;
powering the generator using a turbo-expander;
extracting the excess air flow from the gas turbine system and directing the excess air flow to an inlet of the turbo-expander;
augmenting the excess air flow with additional air using an eductor positioned in an excess air flow path upstream of the turbo-expander, the eductor using the excess air flow as a motive force to create an augmented excess air flow with ambient air that is supplied to an inlet of the turbo-expander, the eductor including a suction side flow path fluidly coupled to an inlet filter of the integral compressor;
directing a discharge of the turbo-expander to an inlet of the integral compressor, wherein a temperature of the discharge of the turbo-expander is less than a temperature of the ambient air;
adjusting a first control valve to direct the augmented excess air flow in the excess air flow path to the inlet of the turbo-expander; and
adjusting a second control valve to in the suction side flow path to direct a flow of the ambient air into the eductor, the flow of the ambient air distinct from the excess air flow.

12. The method of claim 11 , further comprising directing an exhaust of the turbine component to a heat recovery steam generator (HRSG) for creating steam for a steam turbine system.

Assignees

• Gen Electric

Inventors

• Ekanayake Sanji
• Kim Kihyung
• Scipio Alston Ilford
• Tong Leslie Yung Min
• Yarnold Michael Wesley

Classifications

• F05D2220/72

  a steam turbine · CPC title

• F02C3/13

  having variable working fluid interconnections between turbines or compressors or stages of different rotors {(controlling flow ratio between different flows of multi-flow jet-propulsion plant, e.g. ducted fan F02K3/075)} · CPC title

• Y02E20/16

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

• Y02E20/14

  Combined heat and power generation [CHP] · CPC title

• F02C9/18

  by bleeding, bypassing or acting on variable working fluid interconnections between turbines or compressors or their stages {(F02C3/113 takes precedence)} · CPC title