GB2458113A - Monitoring and control systems for an integrated fuel processor and fuel cell system - Google Patents

Monitoring and control systems for an integrated fuel processor and fuel cell system Download PDF

Info

Publication number
GB2458113A
GB2458113A GB0803955A GB0803955A GB2458113A GB 2458113 A GB2458113 A GB 2458113A GB 0803955 A GB0803955 A GB 0803955A GB 0803955 A GB0803955 A GB 0803955A GB 2458113 A GB2458113 A GB 2458113A
Authority
GB
United Kingdom
Prior art keywords
fuel cell
fuel
cell system
fuel processor
integrated
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
GB0803955A
Other versions
GB0803955D0 (en
Inventor
Michael Rendall
George Carins
Jim Carter
Robin Francis
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Voller Energy Ltd
Original Assignee
Voller Energy Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Voller Energy Ltd filed Critical Voller Energy Ltd
Priority to GB0803955A priority Critical patent/GB2458113A/en
Publication of GB0803955D0 publication Critical patent/GB0803955D0/en
Priority to PCT/GB2009/000585 priority patent/WO2009109746A2/en
Publication of GB2458113A publication Critical patent/GB2458113A/en
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/043—Processes for controlling fuel cells or fuel cell systems applied during specific periods
    • H01M8/04302—Processes for controlling fuel cells or fuel cell systems applied during specific periods applied during start-up
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04007—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids related to heat exchange
    • H01M8/04014—Heat exchange using gaseous fluids; Heat exchange by combustion of reactants
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M16/00—Structural combinations of different types of electrochemical generators
    • H01M16/003—Structural combinations of different types of electrochemical generators of fuel cells with other electrochemical devices, e.g. capacitors, electrolysers
    • H01M16/006—Structural combinations of different types of electrochemical generators of fuel cells with other electrochemical devices, e.g. capacitors, electrolysers of fuel cells with rechargeable batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04082—Arrangements for control of reactant parameters, e.g. pressure or concentration
    • H01M8/04089—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04223—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids during start-up or shut-down; Depolarisation or activation, e.g. purging; Means for short-circuiting defective fuel cells
    • H01M8/04225—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids during start-up or shut-down; Depolarisation or activation, e.g. purging; Means for short-circuiting defective fuel cells during start-up
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
    • H01M8/0432—Temperature; Ambient temperature
    • H01M8/04365—Temperature; Ambient temperature of other components of a fuel cell or fuel cell stacks
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
    • H01M8/0432—Temperature; Ambient temperature
    • H01M8/04373—Temperature; Ambient temperature of auxiliary devices, e.g. reformers, compressors, burners
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
    • H01M8/0438—Pressure; Ambient pressure; Flow
    • H01M8/04417—Pressure; Ambient pressure; Flow of the coolant
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
    • H01M8/0438—Pressure; Ambient pressure; Flow
    • H01M8/04425—Pressure; Ambient pressure; Flow at auxiliary devices, e.g. reformers, compressors, burners
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
    • H01M8/04537—Electric variables
    • H01M8/04544—Voltage
    • H01M8/04552—Voltage of the individual fuel cell
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
    • H01M8/04537—Electric variables
    • H01M8/04544—Voltage
    • H01M8/04559—Voltage of fuel cell stacks
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
    • H01M8/04537—Electric variables
    • H01M8/04544—Voltage
    • H01M8/04567—Voltage of auxiliary devices, e.g. batteries, capacitors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
    • H01M8/04537—Electric variables
    • H01M8/04604—Power, energy, capacity or load
    • H01M8/04619—Power, energy, capacity or load of fuel cell stacks
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
    • H01M8/04664—Failure or abnormal function
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
    • H01M8/04701—Temperature
    • H01M8/04738—Temperature of auxiliary devices, e.g. reformer, compressor, burner
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
    • H01M8/04746—Pressure; Flow
    • H01M8/04753—Pressure; Flow of fuel cell reactants
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
    • H01M8/04746—Pressure; Flow
    • H01M8/04776—Pressure; Flow at auxiliary devices, e.g. reformer, compressor, burner
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
    • H01M8/04858—Electric variables
    • H01M8/04865—Voltage
    • H01M8/0488—Voltage of fuel cell stacks
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
    • H01M8/04858—Electric variables
    • H01M8/04865—Voltage
    • H01M8/04888—Voltage of auxiliary devices, e.g. batteries, capacitors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
    • H01M8/04858—Electric variables
    • H01M8/04925—Power, energy, capacity or load
    • H01M8/04947—Power, energy, capacity or load of auxiliary devices, e.g. batteries, capacitors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04694—Processes for controlling fuel cells or fuel cell systems characterised by variables to be controlled
    • H01M8/04955—Shut-off or shut-down of fuel cells
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/06—Combination of fuel cells with means for production of reactants or for treatment of residues
    • H01M8/0606—Combination of fuel cells with means for production of reactants or for treatment of residues with means for production of gaseous reactants
    • H01M8/0612—Combination of fuel cells with means for production of reactants or for treatment of residues with means for production of gaseous reactants from carbon-containing material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/06—Combination of fuel cells with means for production of reactants or for treatment of residues
    • H01M8/0662—Treatment of gaseous reactants or gaseous residues, e.g. cleaning
    • H01M8/0668—Removal of carbon monoxide or carbon dioxide
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/10—Fuel cells with solid electrolytes
    • H01M2008/1095—Fuel cells with polymeric electrolytes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04007—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids related to heat exchange
    • H01M8/04014—Heat exchange using gaseous fluids; Heat exchange by combustion of reactants
    • H01M8/04022—Heating by combustion
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04007—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids related to heat exchange
    • H01M8/04037—Electrical heating
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04223—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids during start-up or shut-down; Depolarisation or activation, e.g. purging; Means for short-circuiting defective fuel cells
    • H01M8/04268—Heating of fuel cells during the start-up of the fuel cells
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/06—Combination of fuel cells with means for production of reactants or for treatment of residues
    • H01M8/0662—Treatment of gaseous reactants or gaseous residues, e.g. cleaning
    • H01M8/0675—Removal of sulfur
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Landscapes

  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Combustion & Propulsion (AREA)
  • Fuel Cell (AREA)

Abstract

A system for monitoring and controlling an integrated fuel processor and fuel cell system is described. The system monitors and checks in real time the status of a number of parameters of the system including temperature, voltage and flow rates and makes changes to the operation of the system to ensure that the system is operating in an optimal and safe condition.

Description

Monitoring And Control Systems For An Integrated Fuel Processor And Fuel Cell System
Technical Field
The current invention is generally related to operating and controlling fuel cell-based electrical generators. More particularly, the current invention relates to useful and practical operational and control processes used in integrated fuel processing and proton exchange membrane (PEM) fuel-cell systems.
Background Art
Fuel cell systems convert fuels into usable electrical power and heat via a controlled electrochemical reaction. Compared to conventional generation technologies, fuel cell systems offer high overall efficiencies, low 1 5 noise, low vibration, and low emissions. There are several different types of fuel cell technologies including proton exchange membrane type (further split into low temperature and high temperature types), solid oxide, molten carbonate, alkaline and phosphoric acid. The most common of these is the proton exchange membrane type (PEM).
PEM fuel cells require high purity hydrogen gas streams to operate and are particularly sensitive to the presence of carbon monoxide. For the low temperature variant, the carbon monoxide content of the gas stream must typically be less than 1 Oppm of the input gas. The high temperature variants can typically tolerate somewhat higher levels of carbon monoxide. Since the provision of high purity hydrogen for widespread application of fuel cells is generally impractical, for commercial application of PEM fuel cells, generation of hydrogen from common fuels, most particularly hydrocarbon fuels, is necessary. Typically such gas streams are produced via processing of a hydrocarbon input in a fuel processor (often referred to as a "reformer") followed by one or more gas purification stages. Common fuel processing routes are steam reforming, partial oxidation, autothermal reforming, pyrolysis (or cracking) and plasma reforming. Typically such processes result in the formation of synthesis gas ("syngas") which is a mixture of hydrogen, carbon oxides, and in some cases other gases. Gas purification processes following initial processing include high and low water gas shift reactions, methanation reactions and preferential oxidation.
For some commercial applications of fuel cells, centralised production of high purity hydrogen followed by storage and transfer of the hydrogen to the fuel cell system is used. However, for many applications, this is impractical or undesirable and a much preferable approach is to use a system in which the fuel processor and fuel cell are integrated into a single package.
Although integrated fuel processor/PEM fuel cell systems are known in the background art, these systems have not realized their commercial potential because of inherent problems in their basic design and operation.
The problems with integrated fuel processor/PEM fuel cell systems are particularly acute for standalone integrated fuel cell systems; i.e. integrated fuel processor/PEM fuel cell systems that only consume fossil fuel feedstock and do not require any additional external source of electrical power or other energy source in order to start-up and operate the system.
In particular the intolerance of hydrogen fuel cells to carbon monoxide and other impurities produced by the reformate chamber place severe demands on the performance of the fuel processor and gas clean up stages.
Because the carbon monoxide and other impurities adversely react, reversibly and irreversibly, with the components of the hydrogen fuel cell stack, carbon monoxide and other impurity levels need to be kept at low: for example, ideally carbon monoxide levels should be no greater than 10 parts per million.
In some cases these can cause irreversible damage to the performance of the fuel cell and system. The impurities produced by the reformate chamber are also partially responsible for another problem with integrated fuel processor/PEM fuel cell systems: the gradual loss of power generated by the stack after several hours of operation. This power loss can be often be reversed by stopping power generation from the stack and allowing the stack time to recover before restarting operations. Ensuring the correct humidity and temperature of the incoming gas steam is another major problem. Even small deviations from the optimum conditions can affect the power produced by the stack considerably.
Another problem with the design of standalone integrated fuel cell systems is ensuring that the system is optimized in such a way to ensure maximum power output without degrading the longevity of the components in the system. One solution to this optimization problem is to ensure that the hydrogen containing feed being consumed by fuel cell stack is of the correct composition and temperature before it enters the stack.
These, and other problems with integrated fuel processor/PEM fuel cell systems and more particularly with standalone integrated fuel cell systems, have made it difficult to create a standalone integrated fuel cell system that permits optimum electricity production without adversely affecting or degrading the components in the system.
One potential solution to these problems is the use of effective control and operational processes. Several inventors have tried to use this solution but most are either non-applicable, or significantly limited, in their use on standalone integrated fuel cell systems. For example US Patent No. 6,759,1 56 "Operating States for Fuel Processor Subsystems", Wheat et al., describes a computerize process for operating a fuel processor/fuel cell system. The patent describes a cyclical process which lacks flexibility: one process, or state, was defined to follow another process or state with no deviation. The described system lacks intelligent design with the feedback
S
information from the system only being used to either move the system from one fixed stage to the next fixed stage or to shutdown the system.
Another example of a limited control system for integrated fuel processor/hydrogen fuel cell systems is US Patent Application Publication 2007/0264546 "Hydrogen-producing fuel cell systems with load-responsive feedstock delivery systems", LaVen, which describes a system that monitors the flow rate of hydrogen gas going into the stack and adjusts the feedstock going into the integrated fuel processor/fuel cell by estimating the fuel cell stack's hydrogen requirements from a calculation based on the external load.
The present invention has been devised to address the technical problem of designing effective control and operating processes to alleviate the inherent problems of an integrated fuel processor/PEM fuel cell system, resulting in a system that permits optimum electricity production without adversely affecting or degrading the long-term operability of the system or the components within the system. In particular these processes are designed to be applicable to standalone integrated fuel cell systems, i.e. integrated fuel processor/PEM fuel cell systems that are powered by fossil fuel feedstock and do not require connection an electricity grid or other external power source.
Statements of the Invention
The current invention achieves this objective by employing several new and novel inventions and procedures, including but not limited to: a programmed computer for constantly monitoring the real-time performance of the standalone integrated fuel cell system and using the monitored feedback information to make real-time operational decisions for the system including, but not limited to: ensuring that the system operates within predefined ranges while generating electrical power; deciding when to start, stop or restart the system based on the external and internal battery voltages and other readings; utilizing alternative start-up and/or restart procedures; selecting the start-up
S
and/or restart procedures on the basis of internal system measurements. The current invention also includes low cost, readily available electronic components and electronic circuitry for monitoring the real-time voltage of the cells in the fuel cell stack and uses unique process to control the flow of the LPG feed into the system to ensure low carbon monoxide levels in the feed to the fuel cell stack.
According to one aspect, the present invention provides an integrated fuel processor and fuel cell system comprising a programmed computer coupled to a plurality of transducers that read the temperatures, voltages and flow rates present in the system wherein said programmed computer controls the on-off fuel feed valves and the power supplied to the heaters, blowers, pumps, and extraction fan in the integrated fuel cell system based on the readings provided by said transducers.
According to another aspect, the present invention provides a device comprising a programmed computer coupled to a plurality of transducers that read the temperatures, voltages and flow rates present in a standalone integrated fuel cell system, wherein said programmed computer controls the on-off fuel feed valve and the power supplied to the heaters, blowers, pumps and extraction fan in the integrated fuel cell system based on the readings provided by said transducers.
The advantageous effects arising from the current invention is a standalone integrated fuel cell system that is designed to produce optimum quantities of electricity from a fossil fuel source without adversely affecting or degrading the long-term operability of the system.
Description of Drawings
Specific embodiments of the present invention will now be described with reference to the accompanying drawings, in which:
S
Figure 1 is a schematic diagram of the major components of a standalone integrated fuel cell system used in an embodiment of the current invention; Figure 2 is a schematic diagram of the control node points for standalone integrated fuel cell system used in an embodiment of the current invention; Figure 3 is a flowchart depicting basic operational processes used in an embodiment of the current invention; Figure 4 is a flowchart depicting a reformer start-up process used in an embodiment of the current invention; Figure 5 is a flowchart depicting a reformate start-up process used in an embodiment of the current invention; Figure 6 is a flowchart depicting a stack start-up process used in an embodiment of the current invention; and IS Figure 7 is a flowchart depicting the steady state mode operational processes used in an embodiment of the current invention.
Detailed Description of Invention
Figure 1 shows a standalone integrated fuel cell system 100 according to one preferred embodiment of the current invention. Liquefied Petroleum Gas, or LPG, from an External LPG Supply 1, along with air from an Air supply 13 and water from a water reservoir 2 is piped into a Reformer 3 which contains a Burner chamber 4 and a Reformate chamber 5. in a preferred embodiment of the current invention, the Reformate chamber 5 also includes an evaporator (not shown) and a CO-Shift reactor 15 (also known as a Water-Gas Shift reactor). The output from the Reformate chamber 5, i.e. the reformate stream, is then piped directly into a final gas processing stage. In a preferred embodiment the final gas processing stage is a Methanation chamber 6. The output from the Methanation chamber 6 is then sent via a thermal management sub-system 7 to a Fuel cell stack 8 which generates electricity for Internal batteries 14 and External batteries 9. The thermal
S
management sub-system 7 is provided to control the temperature of system components and is described in more detail in the Applicant's co-pending application entitled "Heat and Process Water Recovery System" filed on 29 February 2008.
In a preferred embodiment of the current invention, the Reformate chamber 5 is a Cl FLOX� compact reformate chamber made by WS Reformer GmbH of Renningen, Germany, the Methanation chamber 6 is a tubular stainless steel chamber containing 0.5 litres of FC-M9 catalyst made by Süd-Chemie of Bruckmuhl, Germany and the fuel cell stack 8 is a MKIO3OV3 model made by Ballard Power Systems of Vancouver, Canada.
In this preferred embodiment of current invention, the reformer 3 is heated by the Burner chamber 4, the CO-Shift reactor 15 is heated by a 300W power electric heating system and the Methanation chamber 6 is heated by a 200W power electric heating system. The electrical heaters as well as the blowers, pumps, valves and computer control unit 20 used in the system are all powered by a 24V Internal battery bank that can store an amount of power in the range of lOAh to lOOAh, with 30 Ah to 60 Ah being better, and 40 Ah to 50 Ah being the best.
In a preferred embodiment of current invention, the External LPG supply I to the Reformate chamber 5 is controlled by a proportional control valve (not shown). In one preferred embodiment of the current invention, the proportional control valve used is part number LHDA242 121 1 H from The Lee Company of Westbrook, CT, USA.
Further as shown in Figure 1, the sulfur in the LPG is removed prior to entering the reformer by a de-sulfurizer 10.
S
Water is also fed into the Reformate chamber 5. In a preferred embodiment of the current invention, the water is held in a water reservoir 2 and is pumped by an electric water pump (not shown) as a 6 Bar Dl water supply. In addition there are air inlets to the Burner chamber 4. The air fed into these air inlets is generated by an air supply 13, which in this embodiment is an electric reformer blower 13, with the air pressures being regulated by inlet valves.
In the present embodiment, there are two outlets from the Reformer 0 unit 3: the reformate stream and the exhaust gas. In a preferred embodiment of the current invention, the exhaust gas is first cooled by an exhaust-cooling heat exchange unit of the thermal management sub-system 7, with the water present in the exhaust gas being captured by an exhaust water trap and then recycled by gravity to the water reservoir 2. The reformate stream is piped into a Methanation chamber 6 that is set to selectively methanate most of the carbon monoxide in the reformate stream.
in a preferred embodiment of the current invention, before the processed fuel, i.e. the output stream from the Methanation chamber 6, is fed into the fuel cell stack 8, the temperature of the processed fuel is regulated by a heat exchange unit 7 and then run through a water trap to capture any water present in the processed fuel. In addition, in a preferred embodiment of the current invention, the gas flow of the processed fuel going into the fuel cell stack 8 is also modified by the proportional control valve. The processed fuel is then passed through a three-way valve (not shown) that can, if necessary, redirect the processed fuel to the Burner chamber 4 instead of the fuel cell stack 8 and, by an air bleed system (not shown), comprising of an air bleed blower and air valve that can add quantities of air into the hydrogen feed, if necessary.
S
In a preferred embodiment of the current invention, the gas out of the anode side of the fuel cell stack 8, i.e. the unreacted portion of the processed fuel is then fed into the Burner chamber 4 after being passed through two one-way valves and a water trap. The water captured from the water trap is recycled by gravity to the water reservoir 2 via the thermal management sub-system 7.
In a preferred embodiment of the current invention, air from a stack blower is fed into the cathode side of the fuel cell stack 8 with the gas out of the cathode side of the fuel cell stack 8 being passed through a one-way valve and a water trap before being vented to the atmosphere. As with the water collected from the gas out of the anode side, water captured by the water trap from the gas out of the cathode side is also recycled by gravity to the water reservoir 2.
In a preferred embodiment of the current invention, the operational temperature of the fuel cell stack 8 is controlled in part by water fed through the fuel cell stack 8 and passed through a fuel cell stack heat exchanger with any excess heat captured by the fuel cell stack heat exchanger released by an external air cooling unit.
The following describes more details about the various new and novel processes and procedures in the current invention.
Real-Time System Monitoring and Control As shown in Figure 3, in an embodiment of the current invention, there are three basic operating modes for the system 100: Start-Up, Steady State and Standby. Further as shown in Figure 3, and as further detailed in Figures 4, 5 and 6 respectively, the Start-Up mode comprises of three processes: Reformer start-up, Reformate start-up, and Stack start-up.
S
As shown in Figure 3, in a preferred embodiment of the current invention, after a user presses an "ON" button on the system at step S3-1, the system checks at step S3-3 if the desired parameters from a Start-Up mode have been reached. The system's operating mode is determined in dependence upon the voltages of the Internal and External batteries (Pt and P2 shown in Figure 2) and their respective predefined upper and lower set points. For example, when the system detennines at step S3-3 that both batteries are above their upper voltage set points, the system moves to the Standby mode in step S3-5 and remains in this mode until the voltages (P1,P2) of either the Internal battery 14 or External battery 9 falls below a predefined lower voltage set point, as determined by the system at step S3-7.
If the system determines at step S3-3 or step S3-7 that either battery voltage is below the predefined lower voltage set point, the system 100 moves to the Steady State mode (at step S3-17, discussed below) via the Start-Up mode (steps S3-9 to S3-13 discussed below) until both batteries are above their upper set points, as determined by the system at step S3-19. Then the system returns to the Standby mode (step S3-5).
For the Internal battery 14, the lower set point is 1 8 -22 V, with 19 - 2lV being better, and 20V being the best. For the External battery 9, the lower set point is 18 -22 V, with 19-2lV being better, and 20V being the best. For the Internal battery 14, the upper set point is 26 -30V, with 27 - 29V being better, and 28V being the best. For the External battery 9, the upper set point is 26 -30V, with 27 -29V being better, and 28V being the best.
Further, as depicted in Figure 7 and Table 1 below, the system 100 can also move from the Steady State mode to the Standby mode on the basis of the lowest single cell voltages P9 within the fuel cell stack 8 or other measurements made in the system 100. Under these circumstances, the computer control unit 20 also generates a fault code or error message which
S
needs to be cleared by human intervention in order for the system 100 to return to the Steady State mode.
Steady State mode As discussed above, the system 100 moves to the Steady State mode at step S3-17. Operation of the system in this mode, in a preferred embodiment of the current invention, is illustrated in more detail in Figure 7. The system produces electrical power under the Steady State mode. In the Steady State mode, the computer control unit 20 continuously monitors a large number of parameters. As shown in Figure 7, at step S7-I, the system 100 monitors if the lowest cell in the fuel cell stack 8 is at a voltage below 0.5V.
At step S7-3, the system 100 monitors if the lowest cell in the fuel cell stack is at a voltage below 0.1 V. At step S7-5, the system 100 monitors if the burner chamber 4 is at a temperature below 700C. At step S7-7, the system 100 monitors if the methanation chamber is at a temperature below I 95C. At step S7-9, the system 1 00 monitors if the shift reactor I 5 is at a temperature below 200C. As set out in Table I below, when the parameters are within the predefined steady state ranges, the computer control unit 20 makes no changes to the system 100 and only takes the actions as listed in Table I (and as shown in Figure 7) when the measurements are above or below the steady state range.
The parameters of the Steady State mode that are continuously monitored by the computer control unit 20 are listed in Table I below. Figure 2 shows the basic layout of the fuel cell system 100 and shows where each of the control nodes are measured. As shown in Figure 2, in the present embodiment, the measured system parameters are: the external battery voltage (P1) measured at the external battery 9, the internal battery voltage (P2) measured at the internal battery 14, the reformer burner temperature (P3) measured at the Burner chamber 4, the Shift temperature (P4) measured at the CO-Shift reactor 1 5, the Reformate transfer temperature (P5) measured between the CO-shift reactor 15 and the Methanation chamber 6, the Methanation temperature (P6) measured at the Methanation chamber 6, the Stack reformate temperature (P7) measured between the Methanation chamber 6 and the fuel cell stack 8, the Steam pressure (P8) measured between the water reservoir 2 and the reformate chamber 5, and the Lowest cell voltage (P9) and the stack coolant flow (P10) measured at the fuel cell stack 8.
Table I
Steady state Action if under Control node range range Action if over range External batteries voltage Go to steady (V) -P1 20.OV -28V state mode Go to standby mode Divert power to Internal batteries voltage Go to steady charging external (V) -P2 20.OV -28V state mode batteries Reformer burner temp Error. Go to Reduce airflow to (deg C) -P3 820°C -865°C standby mode burner Shift temperature (deg C) Turn on shift Error. Go to standby -P4 175°C -300°C heater mode Reformate transfer Turn on transfer temperature (deg C) -P5 210°C tube heater No action Turn on Methanation temperature methanation Error. Go to standby (deg C) -P6 195°C -275°C heaters x2 mode Turn off stack Stack reformate heat exchanger Turn on stack heat temperature (deg C) -P7 60°C fan exchanger fan Steam pressure (barg) -6barg ON Error. Go to standby P8 (digital switch) Keep on mode Lowest cell voltage (V) -Increase voltage P9 0.5V set point No action Stack coolant flow ON (digital Error. Go to standby (SLPM) -PlO switch) No Action mode The system component parameters can be monitored several times per second. In the preferred embodiment, they are monitored three times per second.
Table I also lists the target or desired range of each parameter when in steady-state mode and the actions taken automatically by the system 100 if any of these parameters are under or over the target values. As discussed above, the computer control unit 20 operates to control various components such as heaters and fans of the system 100, for example as set out in Table 1.
In the preferred embodiment, these decisions are taken three times a second for each control point.
Pulsed LPG Feed In addition, in a preferred embodiment of the current invention, it also been found that by pulsing the LPG feed into the system 100, the carbon monoxide levels produced in the refonnate stream are lowered. This is achieved in an embodiment of the current invention by using the computer control unit 20 to control the opening and closing of the proportional control valve at the frequency in the range of 100Hz to 10Hz being good, and a frequency of 10Hz being the optimum, for producing reduced carbon monoxide emissions and preserving the lifetime of the proportional control valve. Further, in a preferred embodiment of the current invention, it has been found that a 90% pulse (i.e. 90% on, 10% off) is optimal for producing reduced carbon monoxide emissions when the system is fully generating electrical power in the steady state mode.
Fuel Cell Stack Monitoring As shown in Figure 7, in a preferred embodiment of the current invention, the lowest voltage of any single cell in the fuel cell stack 8, is used in the steady state mode to determine whether or not to generate a fault code and return the system to the Standby mode. In a preferred embodiment of the
S
current invention, the voltages of the individual cells of the fuel cell stack 8 are monitored by low cost electronic circuitry and components. Further, nested arrays of transducers are used for measuring the voltages of the individual fuel cells in the stack 8.
Voltage Control and Start-Up As discussed above with reference to Figure 3, prior to entering the Steady State mode at step S3-17, the system 100 undergoes an external and internal battery 9,14 voltage check and system start-up procedure. The basic start-up operating procedure is illustrated in Figure 3. When the user turns the system ON (step S3-l), the system 100 automatically checks the voltage level of the external and internal batteries P1,P2. If these are above a certain threshold (set by software) the system will enter "Standby" mode. If either battery voltage P1,P2 is below this threshold for a certain amount of time (set by software), the system 100 will begin the start-up procedure. The system will also begin the start-up procedure if at any time either the external P1 or internal P2 battery voltage drops below the voltage threshold for a certain amount of time whilst in Standby mode.
Start-Up Processes Start-up processes are needed to ensure that the system 100 reaches its operational objectives. As explained herein the operational steady state of the system 100 is based on components in the system reaching predetermined measurable states, i.e. temperatures, flow rates and pressures. In order to move the system 100 to these predetermined measurable states, the system needs to use start-up procedures and processes.
As shown in Figure 3, the Start-Up mode comprises of three processes: Reformer start-up (at step S3-9), Reformate start-up (at step S3- 11), and Stack start-up (at step S3-1 3). The various start-up processes at steps S3-9, S3-1 1 and S3-l3 of Figure 3, are illustrated in more detail in Figures 4 to 6, respectively.
During start-up, parts of the system 100 require heating from one of the external sources (LPG burner or electrical heaters operating from internal battery 14 power) to reach operational temperatures. The system 100 does not know the ambient temperature so it can only make decisions based on its internal temperatures (eg. P3 to P7) and when these reach their set points after heating. Therefore the burner solenoid remains open until the burner temperature is at 850C. The Methanation heater remains on until the inlet temperature is at I 95C and the Shift reactor heater remains on until the temperature in the Shift reactor is at 200C. When the temperatures fall below these set points, the heaters are turned on and the burner solenoid opens to allow LPG to be supplied to the burner.
Reformer Start-up Process Figure 4 is a flow diagram illustrating the Reformer 3 Start-up Process (step S3-9 in Figure 3). The system 100 monitors system parameters during the reformer start-up process and controls system components in accordance with the monitored system parameters.
In particular, at step S4-1, the system 100 monitors the burner chamber 4 temperature and if it is determined to be at a temperature under 700C, then the burner chamber 4 is purged at step S4-3, the fuel valve is opened at step S4-5, and a spark is set off at step S4-7. At step S4-7, the system 100 determines if a flame is detected, for example by determining if an electrical signal from a flame detector is above 5V. If a flame is not detected, then at step S4-9, the system 100 determines, at step S4-1 1, if there has been a predefined number of attempts (for example, five) before issuing a fault code at step S4-13. If the system 100 detects a flame at step S4-9, then at step S4-15, the system 100 determines if the temperature of the burner chamber 4 is below 700C. If it is, the fuel valve is left open at step S4-1 7 and the system 100 adjusts the blower flow rate for the combustion air supply to use settings associated with a flame air mode. If not, the system determines, at step S4-19, if the temperature of the burner chamber 4 is below 850C. If it is, the fuel valve is left open at step S4-2 I and the system 100 configures the blower flow rate for the combustion air supply with Flameless Oxidation (FLOX) air mode settings. If not, the system determines, at step S4-l9, if the temperature of the burner chamber 4 is below 865C. If it is, the system 100 stops supply of air to the burner chamber 4 at step S4-25 and the process returns to step S4-15. However, if the system 100 determines at step S4-23 that the temperature of the burner chamber 4 is at or above 865C, then at step S4-27 it is determined that the FLOX air settings have reaches a set point, and the fuel valve is closed.
In addition, at step S4-29, the system 100 monitors the methanation chamber 6 temperature and if it is determined to be at a temperature under I 95C, then the methanation chamber heaters are turned on at step S4-3 I. If not, the system 100 determines at step S4-33 if the temperature of the methanation chamber 6 is below 275C. If it is, the methanation chamber heater is turned off at step S4-35. If at step S4-33, the system 100 determines that the temperature of the methanation chamber is above 275C, then a fault code is issued at step S4-37 and the system 100 is set to a standby mode.
Additionally, at step S4-39, the system 100 monitors the shift reactor 1 5 temperature and if it is determined to be at a temperature under 200C, then the shift reactor heaters are turned on at step S4-41. Once the system 100 determines at step S4-39 that the temperature of the shift reactor 15 is at 200C, the shift reactor heater is turned off at step S4-43.
The reformate start-up process is complete once the burner chamber 4, shift reactor 1 5 and methanation chamber 6 temperatures are all at their respective set points (setep S4-45).
Reformate Start-up Process Figure 5 is a flow diagram illustrating the reformate Start-up Process (step S3-l I in Figure 3). At step S5-l, the system 100 starts a reformer water pump (not shown) and monitors the steam pressure in the reformer 3 at step S5-3 until the steam pressure is at 5bar. The system 100 waits at step S5-5 until it is determined that the steam pressure is at 5bar, and which point the system 100 opens the reformer feed valve to 50% (at step S5-7).
In addition, at step S5-9, the system 100 monitors the fuel cell stack 8 and determines if the lowest cell has a voltage less than 0.IV. If it does not, at step S5-11, the system opens a stack bleed relay. Once the lowest cell has a voltage less than 0.1 V, the system 100 starts a stack water pump and air bleed at step S5-l3. At step S5-15, the system 100 determines if there is stack coolant flow and if so, the reformate start-up process is complete and stack start-up process can begin, as discussed below with reference to Figure 6.
However, if there is no stack coolant flow, then the system 100 issues a fault code at step S5-1 7 and moves the system 100 to standby mode.
Start-Up Selection Process Figure 6 is a flow diagram illustrating the stack start-up process (step S3-l3 in Figure 3). At step S6-l, the system 100 opens a stack fuel valve and monitors the voltage of the lowest cell in the fuel cell stack 8 at step S6-3 until voltage is at 0.9V. The system 100 waits at step S6-5 until it is determined that the voltage of the lowest cell is at 0.9V, and which point the system 100 opens the stack relay (at step S6-7). At step S6-9, the system 100 reduces the stack voltage set point by dV and determines at step S6-l I if the fuel cell stack 8 voltage is at the set point. If it is not, the system 100 issues a fault code at step S6-1 3 and moves to a standby mode. If it is, the system 100 determines at step S6-15 if the fuel cell stack 8 voltage is at half power, and if not, the stack voltage set point is further reduced at step S6-9. Once the system 100 detennines at step S6-1 5 that the fuel cell stack 8 voltage is at half power, then at step S6-1 7, the system 100 determines if the fuel cell stack 8 outlet temperature is above 50C. If it is not, the system 100 waits at half power (step S6-l 9) until the fuel cell stack 8 outlet temperature is above 50C.
At this point, there are two different start-up procedures depending on whether the temperature of the CO-Shift reactor P4 is found to be equal to, or above, a set point temperature (step S6-2 1). In the default case where the CO-shift reactor is below this set point (referred to as a "cold start"), the Stepped LPG Feed Start-Up Process is used, as discussed below. In the case that the CO-shift reactor is above this set point (referred to as a "hot restart"), then the Pulsed LPG Feed Start-Up Process is used instead. In the preferred embodiment of the current invention as described herein, it has been found that a temperature of the CO-Shift reactor P4 at a set point temperature of 190 -210 degrees centigrade is possible, a set point temperature of 195 -205 degrees centigrade is good, and a set point temperature of 200 degrees centigrade is the best. The cold and hot restart processes are both described below and illustrated in Figure 6.
Stepped LPG Feed Start-Up Process ("cold start ") If at step S6-2 I, the system 100 determines that the temperature of the shift reactor 15 is below 200C, then a "cold start" process is to be perfonned.
In this process, the LPG reforn-iate feed is increased in two stages. In the preferred embodiment, these two stages are 50 and 100% of maximum feed rate. Following opening of the feed to the maximum extent (step S6-23), the fuel cell stack 8 is increased to full power via a series of incremental decreases in voltage set point (step S6-25). At step S6-27, the system 100 determines if the fuel cell stack 8 is at the voltage set point and if it is not,
S
then the system 100 issues a fault code at step S6-29 and moves to a standby mode. If it is, the system 100 then determines when the fuel cell stack 8 is at full power (setp S6-3 1) and moves to the steady state mode discussed above.
Pulsed LPG Feed Start-Up Process ("Hot restart ") If at step S6-2 1, the system 100 deternines that the temperature of the shift reactor 1 5 is at or above 200C, then a "hot start" process is to be performed. In this process, the LPG reformate is increased incrementally using a proportional control valve (step S6-33). The voltage set point is then decreased to follow the feed control valve set point (step S6-35) until the stack is at full power. Accordingly, at step S6-37, the system 100 determines if the fuel cell stack 8 is at the voltage set point and if it is not, then the system issues a fault code at step S6-39 and moves to a standby mode. If it is, the system 100 then detern-iines when the fuel cell stack 8 is at full power (step S6-43) and moves to the steady state mode discussed above.
Alternative Embodiments It will be understood that embodiments of the present invention are described herein by way of example only, and that various changes and modifications may be made without departing from the scope of the invention.
For example, in the embodiment described above, various fans, heaters and valves are controlled by a control device depending on monitored system parameters. As those skilled in the art will appreciate, the precise components being controlled in response to changes in the monitored parameters will depend on the implemented system. Accordingly, in addition to controlling fans, heaters and valves, the system may also control other components such as pumps and relays in order to modify operation of the system in response to monitored parameters.
It is believed that this disclosure encompasses multiple distinct inventions with independent utility. While each of these inventions has been disclosed in its preferred form, the specific embodiments thereof as disclosed and illustrated herein are not to be considered in a limiting sense as numerous variations are possible. The subject matter of the disclosure includes all novel and non-obvious combinations and subcombinations of the various elements, features, functions, and/or properties disclosed herein. Similarly, where the claims recite "a" or "a first" element or the equivalent thereof, such claims should he understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements.
The following claims particularly point out certain combinations and subcombinations that are directed to one of the disclosed inventions and are novel and non-obvious. Inventions embodied in other combinations and subcombinations of features, functions, elements, and/or properties may be claimed through amendment of the present claims or presentation of new claims in this or a related application. Such amended or new claims, whether they are directed to a different invention or directed to the same invention, whether different, broader, narrower or equal in scope to the original claims, are also regarded as included within the subject matter of the inventions of the current invention.

Claims (31)

  1. Claims: I. An apparatus for controlling an integrated fuel processor and fuel cell system, the apparatus comprising: means for receiving a plurality of system parameter values from a respective plurality of transducers, the system parameter values including temperatures, voltages and flow rates of components in the system; means for controlling operation of components of the system based on the plurality of system parameter values provided by said transducers, wherein the means for controlling operation is operable to control fuel feed valves to enable and disable fuel input to the system and to control heating, cooling and battery units in the system based on the parameter values provided by said transducers.
  2. 2. An integrated fuel processor and fuel cell system comprising: a plurality of system components, the components including fuel feed valves and heating, cooling and battery units; a plurality of transducers for reading and providing a respective plurality of system parameter values, the system parameter values including temperatures, voltages and flow rates of the plurality of components in the system; a programmed computer as set out in claim I, the programmed computer being coupled to the plurality of transducers and operable to control operation of the plurality of system components based on the plurality of system parameter values provided by said transducers.
  3. 3. An integrated fuel processor and fuel cell system according to claim 2 whereby the system is operated as a standalone unit not connected to an electrical grid.S
  4. 4. An integrated fuel processor and fuel cell system according to any preceding claim, wherein the programmed computer is operable to start, stop or restart operation of the system based on the plurality of system parameter values provided by said transducers.
  5. 5. An integrated fuel processor and fuel cell system according to any preceding claim, further comprising a steam reformer as a fuel processor.
  6. 6. .An integrated fuel processor and fuel cell system according to any preceding claim, further comprising a proton exchange membrane, PEM, fuel cell.
  7. 7. An integrated fuel processor and fuel cell system according to any preceding claim, wherein the system is arranged to receive Liquefied Petroleum Gas, LPG, as fuel.
  8. 8. An integrated fuel processor and fuel cell system according to any preceding claim, wherein the system comprises nested arrays of transducers for measuring the voltages of individual fuel cells in a fuel cell stack.
  9. 9. An integrated fuel processor and fuel cell system according to any preceding claim, wherein the heating units comprise a burner solenoid for a Reformate unit, and wherein the programmed computer is operable to keep the burner solenoid open until the burner temperature is at a predetermined temperature.
  10. 10. An integrated fuel processor and fuel cell system according to claim 9, wherein the predetermined burner temperature is 850C.
  11. 11. An integrated fuel processor and fuel cell system according to any preceding claim, wherein the heating units comprise a Methanation heater forSa Methanation unit, and wherein the programmed computer is operable to keep the Methanation heater on until an inlet temperature is at a predetermined temperature.
  12. 12. An integrated fuel processor and fuel cell system according to claim 11, wherein the predetermined inlet temperature is I 95C.
  13. 13. An integrated fuel processor and fuel cell system according to any preceding claim, wherein the Methanation heater comprises a 200W power electric heating system.
  14. 14. An integrated fuel processor and fuel cell system according to any preceding claim, wherein the heating units comprise a Shift reactor heater for a CO-Shift reactor, and wherein the programmed computer is operable to keep the Shift reactor heater on until the temperature in the CO-Shift reactor is at a predetermined temperature.
  15. 15. An integrated fuel processor and fuel cell system according to claim 14, wherein the predetermined CO-Shift reactor temperature is 200C.
  16. 16. An integrated fuel processor and fuel cell system according to any claim 15, the Shift reactor heater comprises a 300W power electric heating system.
  17. 17. An integrated fuel processor and fuel cell system according to any preceding claim, wherein the components in the system are powered by a 24V internal battery bank than can store an amount of power in the range of I OAh to lOOAh.
  18. 18. An integrated fuel processor and fuel cell system according to claim 17, wherein the components in the system are powered by a 24V internalSbattery bank than can store an amount of power in the range of 30 Ah to 60 Ah.
  19. 19. An integrated fuel processor and fuel cell system according to claim 18, wherein the components in the system are powered by a 24V internal battery bank than can store an amount of power in the range of 40 Ah to 50 Ah.
  20. 20. An integrated fuel processor and fuel cell system according to any preceding claim, wherein the battery unit comprises an internal and/or an external battery.
  21. 21. A method for controlling an integrated fuel processor and fuel cell system, the method comprising the steps of: receiving a plurality of system parameter values from a respective plurality of transducers, the system parameter values including temperatures, voltages and flow rates of the plurality of components in the system; controlling operation of fuel feed valves to enable and disable fuel input to the system and controlling operation of heating, cooling and battery units in the system, based on the parameter values provided by said transducers.
  22. 22. The method of claim 21, wherein controlling the heating, cooling and battery units in the system further comprises initiating a start-up operating mode for the system wherein components of the system are heated to predefined operational temperatures.
  23. 23. The method of claim 22, further comprising determining whether to move the operating mode for the system to a Steady State operating mode wherein the system produces electrical power or a Standby operating mode wherein no changes are made to the system.
  24. 24. The method of claim 23, wherein the determination is made depending on the voltages of internal and external batteries in the system and respective predefined upper and lower set points.
  25. 25. The method of any one of claims 21 to 24, wherein when the voltages of both the internal and external batteries are above their respective upper voltage set points, the system is moved to the Standby operating mode.
  26. 26. The method of claim 25, wherein the system remains in the Standby operating mode until the voltages of either the internal battery or external battery falls below the respective predefined lower voltage set point.
  27. 27. The method of claim 26, wherein the system is moved to the Steady State mode when the voltages of either the internal battery or external battery falls below the respective predefined lower voltage set point, until the voltages of both batteries are above their respective upper set points.
  28. 28. The method of claim 27, wherein the lower set point for the internal battery and/or the external battery is between 18 and 22 V.
  29. 29. The method of claim 28, wherein the lower set point for the internal battery and/or the external battery is between 19 and 21 V.
  30. 30. The method of claim 29, wherein the lower set point for the internal battery and/or the external battery is 20V.
  31. 31. The method of claim 27, wherein the upper set point for the internal battery and/or the external battery is between 26 and 30V.I32. The method of claim 31, wherein the upper set point for the internal battery and/or the external battery is between 27 and 29V.33. The method of claim 32, wherein the upper set point for the internal battery and/or the external battery is 28V.34. The method of any one of claims 23 to 33, wherein the system is moved from the Steady State operating mode to the Standby operating mode on the basis of the lowest single cell voltages within a fuel cell stack in the system.35. The method of any one of claims 21 to 34, wherein system parameter values from a respective plurality of transducers are received three times per second.36. The method of any one of claims 21 to 35, wherein the heating units comprise a burner solenoid for a Reformate unit, and wherein the burner solenoid remains open until the burner temperature is at 850C.37. The method of any one of claims 21 to 36, wherein the heating units comprise a Methanation heater for a Methanation unit, and wherein the Methanation heater remains on until an inlet temperature is at a predetermined temperature.38. The method of claim 37, wherein the predetermined inlet temperature is 195C.39. The method of any one of claims 21 to 38, wherein the heating units comprise a Shift reactor heater for a CO-Gas Shift reactor, and wherein the Shift reactor heater remains on until the temperature in the CO-Shift reactor is at a predetermined temperature.40. The method of claim 39, wherein the predetennined CO-Shill reactor temperature is 200C.41. An integrated fuel processor and fuel cell system substantially as herein described with reference to the accompanying drawings.42. A control apparatus substantially as herein described with reference to the accompanying drawings.43. A control method substantially as herein described with reference to the accompanying drawings.
GB0803955A 2008-03-03 2008-03-03 Monitoring and control systems for an integrated fuel processor and fuel cell system Withdrawn GB2458113A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB0803955A GB2458113A (en) 2008-03-03 2008-03-03 Monitoring and control systems for an integrated fuel processor and fuel cell system
PCT/GB2009/000585 WO2009109746A2 (en) 2008-03-03 2009-03-03 Monitoring and control systems for an integrated fuel processor and fuel cell system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB0803955A GB2458113A (en) 2008-03-03 2008-03-03 Monitoring and control systems for an integrated fuel processor and fuel cell system

Publications (2)

Publication Number Publication Date
GB0803955D0 GB0803955D0 (en) 2008-04-09
GB2458113A true GB2458113A (en) 2009-09-09

Family

ID=39315880

Family Applications (1)

Application Number Title Priority Date Filing Date
GB0803955A Withdrawn GB2458113A (en) 2008-03-03 2008-03-03 Monitoring and control systems for an integrated fuel processor and fuel cell system

Country Status (2)

Country Link
GB (1) GB2458113A (en)
WO (1) WO2009109746A2 (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5366821A (en) * 1992-03-13 1994-11-22 Ballard Power Systems Inc. Constant voltage fuel cell with improved reactant supply and control system
JP2003157871A (en) * 2001-11-22 2003-05-30 Toshiba Corp Fuel cell power generation system and control system for the same
JP2006310109A (en) * 2005-04-28 2006-11-09 Babcock Hitachi Kk Fuel cell power generating system
WO2007019208A2 (en) * 2005-08-03 2007-02-15 Genesis Fueltech, Inc. Reformer and fuel cell system control and method of operation
US20070264546A1 (en) * 2006-05-15 2007-11-15 Laven Arne Hydrogen-producing fuel cell systems with load-responsive feedstock delivery systems

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06140065A (en) * 1992-09-08 1994-05-20 Toshiba Corp Fuel cell power generating system
JP4244399B2 (en) * 1998-05-14 2009-03-25 トヨタ自動車株式会社 FUEL CELL SYSTEM, ELECTRIC VEHICLE HAVING THE SAME AND FUEL CELL SYSTEM START-UP CONTROL METHOD
US20060194082A1 (en) * 2005-02-02 2006-08-31 Ultracell Corporation Systems and methods for protecting a fuel cell
US7476455B2 (en) * 2006-07-10 2009-01-13 Protonex Technology Corporation Portable fuel cell system

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5366821A (en) * 1992-03-13 1994-11-22 Ballard Power Systems Inc. Constant voltage fuel cell with improved reactant supply and control system
JP2003157871A (en) * 2001-11-22 2003-05-30 Toshiba Corp Fuel cell power generation system and control system for the same
JP2006310109A (en) * 2005-04-28 2006-11-09 Babcock Hitachi Kk Fuel cell power generating system
WO2007019208A2 (en) * 2005-08-03 2007-02-15 Genesis Fueltech, Inc. Reformer and fuel cell system control and method of operation
US20070264546A1 (en) * 2006-05-15 2007-11-15 Laven Arne Hydrogen-producing fuel cell systems with load-responsive feedstock delivery systems

Also Published As

Publication number Publication date
WO2009109746A3 (en) 2010-03-25
WO2009109746A2 (en) 2009-09-11
GB0803955D0 (en) 2008-04-09

Similar Documents

Publication Publication Date Title
CN110710040B (en) Method and system for producing hydrogen, electricity and co-production
JP7400524B2 (en) Fuel cell system and method of operating the fuel cell system
KR100824841B1 (en) Utilization-based fuel cell monitoring and control
WO2012153482A1 (en) Power generation system, and method for operating same
US8277997B2 (en) Shared variable-based fuel cell system control
EP2426769A1 (en) Reformer for fuel cell
US20130137006A1 (en) Power generation system and method of operating the same
JP4773431B2 (en) Usage-based fuel cell monitoring and control
US9640820B2 (en) Power generation system and method of operating the same
GB2458113A (en) Monitoring and control systems for an integrated fuel processor and fuel cell system
KR20120070725A (en) Control unit and control method for fuel cell system
JP5796227B2 (en) Fuel cell power generation system and method for stopping operation of fuel cell power generation system
JP4751589B2 (en) Fuel cell power generation system
JP3897149B2 (en) Solid oxide fuel cell and Stirling engine combined system
JP2007026998A (en) Fuel cell temperature control method for fused carbonate type fuel cell power generator, and device for the same
JP4467929B2 (en) Fuel cell power generation system
KR102559980B1 (en) Fuel cell with improved efficiency by having an air supply unit that can control the amount of air supplied
JP4917791B2 (en) Fuel cell system
JP2001185182A (en) Power generating device for fuel cell and its operating method
CN117525494A (en) Operation control method and device of cascade reformer and SOFC power generation system
KR101313880B1 (en) Method for managing stationary fule cell system
JP2023081178A (en) Fuel cell system and control method for fuel cell system
CN117832556A (en) SOFC power generation system for methanol-water combustion reforming
JP2014214048A (en) Hydrogen generator and fuel cell system
JP2014182928A (en) Fuel cell system

Legal Events

Date Code Title Description
732E Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977)

Free format text: REGISTERED BETWEEN 20100114 AND 20100120

WAP Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1)