Rapid start hybrid solid oxide fuel cell power system

Patent metadata

Field	Value
Publication number	US-10644331-B2
Application number	US-201615332191-A
Country	US
Kind code	B2
Filing date	Oct 24, 2016
Priority date	Oct 24, 2016
Publication date	May 5, 2020
Grant date	May 5, 2020

Abstract

A rapid start power unit and a method of operating a rapid start power unit are disclosed. A fuel cell converts combustible fuel into electrical power during a normal operational period after an initial start-up period when little to no electrical energy is produced. One combustion chamber receives unspent fuel emitted by the fuel cell and combusts the unspent fuel to generate a first heated gas stream. Another combustion chamber receives combustible fuel and burns the combustible fuel to generate a second heated gas stream during the initial start-up period. A turbine receives and is driven by the first and second heated gas streams to drive a drive shaft. A generator coupled to the drive shaft generates electrical power during the initial start-up period and supplemental power during the normal operational period. In an alternative embodiment, a two-stage combustion chamber is used instead of two serially-arranged separate combustion chambers.

First claim

What is claimed is:

1. A rapid start power unit comprising:
a fuel cell configured to convert combustible fuel into electrical power after a first time period and during a second time period that follows the first time period;
a first combustion chamber configured to receive unspent fuel from the fuel cell and to combust the unspent fuel to generate a first heated gas stream;
a second combustion chamber configured to receive combustible fuel from a fuel source, to burn the combustible fuel to generate a second heated gas stream during the first time period, and to disconnect from the fuel source during the second time period;
a turbine configured to receive the first heated gas stream and the second heated gas stream and to be driven by the first heated gas stream and the second heated gas stream, the turbine further configured to drive a drive shaft; and
a generator coupled to the drive shaft, the generator configured to generate, in response to the drive shaft, electrical power during the first time period and during the second time period.

2. The rapid start power unit of claim 1 , further comprising a compressor coupled to the drive shaft, the compressor configured to compress a source of oxidizing gas for supplying compressed oxidizing gas to the fuel cell.

3. The rapid start power unit of claim 1 , wherein the fuel cell is a solid oxide fuel cell and the combustible fuel is a hydrocarbon fuel.

4. The rapid start power unit of claim 1 , further comprising a reformer configured to assist in converting the combustible fuel into reactants used by the fuel cell.

5. The rapid start power unit of claim 4 , wherein the reformer is one of a steam reformer, a catalytic partial oxidation reformer, or an autothermal reformer.

6. The rapid start power unit of claim 4 , wherein the reactants converted from the combustible fuel by the reformer include carbon monoxide and hydrogen.

7. The rapid start power unit of claim 1 , wherein the first combustion chamber is a catalytic combustion chamber.

8. A rapid start power unit comprising:
a fuel cell configured to convert combustible fuel into electrical power after a first time period and during a second time period that follows the first time period;
a two stage combustion chamber including:
a first stage configured to receive unspent fuel emitted by the fuel cell and to combust the unspent fuel to generate a first heated gas stream; and
a second stage configured to receive combustible fuel from a fuel source, to burn the combustible fuel to generate a second heated gas stream during the first time period, and to disconnect from the fuel source during the second time period;

a turbine configured to receive the first heated gas stream and the second heated gas stream and to be driven by the first heated gas stream and the second heated gas stream, the turbine being further configured to drive a drive shaft; and
a generator coupled to the drive shaft, the generator configured to generate, in response to the drive shaft, electrical power during the first time period and during the second time period.

9. The rapid start power unit of claim 8 , further comprising a compressor coupled to the drive shaft, the compressor configured to compress a source of oxidizing gas for supplying compressed oxidizing gas to the fuel cell.

10. The rapid start power unit of claim 8 , wherein the fuel cell is a solid oxide fuel cell and the combustible fuel is a hydrocarbon fuel.

11. The rapid start power unit of claim 8 further comprising a reformer configured to assist in converting the combustible fuel into reactants used by the fuel cell.

12. The rapid start power unit of claim 11 , wherein the reformer is one of a steam reformer, a catalytic partial oxidation reformer, or an autothermal reformer.

13. The rapid start power unit of claim 11 , wherein the reactants converted from the combustible fuel by the reformer include carbon monoxide and hydrogen.

14. The rapid start power unit of claim 8 , wherein the first stage of the two stage combustion chamber is a catalytic combustion chamber.

15. A method for rapidly supplying electrical power, the method comprising:
generating electrical power using a chemical conversion of combustible fuel after a first time period and during a second time period that follows the first time period;
combusting, in a first combustion chamber, unspent fuel emitted by the chemical conversion of the combustible fuel to generate a first heated gas stream;
burning, in a second combustion chamber, combustible fuel received from a fuel source to generate a second heated gas stream during the first time period;
using the first heated gas stream and the second heated gas stream to mechanically drive a generator to produce electrical power during the first time period;
disconnecting the second combustion chamber from the fuel source during the second time period; and
using the first heated gas stream to mechanically drive the generator to produce electrical power during the second time period.

16. The method of claim 15 , wherein the step of using the first heated gas stream and the second heated gas stream to mechanically drive the generator comprises providing the first heated gas stream and the second heated gas stream to a turbine that drives a drive shaft coupled to the generator to produce electricity.

17. The method of claim 15 , wherein a fuel cell performs the step of chemically converting combustible fuel into electrical power.

18. The method of claim 17 , wherein the first time period corresponds to an initial start-up period of the fuel cell, and wherein the second time period corresponds to a normal operational period of the fuel cell.

19. The method of claim 17 , wherein the first time period ends and the second time period begins upon warmup of the fuel cell.

20. The method of claim 15 , further comprising, after disconnecting the fuel source from the second combustion chamber, inertly passing the first heated gas stream through the second combustion chamber.

Assignees

• Boeing Co

Inventors

• Stoia Tina
• Atreya Shailesh
• Balan Chellappa
• Whelan David
• Glll David J
• Castelli Vincent J

Classifications

• H01M8/04225

  during start-up · CPC title

• H01M8/04022 Primary

  Heating by combustion · CPC title

• H01M8/04111

  using a compressor turbine assembly · CPC title

• H01M8/0662

  Treatment of gaseous reactants or gaseous residues, e.g. cleaning · CPC title

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title