摘要:
A system and method for correcting an estimation of nitrogen in an anode side of a fuel cell stack. The system includes a fuel cell stack and a pressure sensor for measuring pressure in an anode sub-system. The system also includes a controller configured to control the estimation of nitrogen permeation from the cathode side to the anode side of the stack, where the controller determines if the pressure in the anode sub-system equilibrates with atmospheric pressure in a shorter period of time after shutdown compared to the time necessary for the anode sub-system to reach approximately atmospheric pressure after a previous shutdown or calibrated time value, and corrects the estimation of nitrogen in the anode side of the stack if the pressure equilibrates in a shorter period of time.
摘要:
A model uses various operating characteristics of a fuel cell to predict the relative humidity profile that is occurring within the fuel cell as a function of the reaction progress. The model is used to predict the relative humidity profile that will occur in response to changes to one or more of the operating characteristics of the fuel cell. A high frequency resistance of the fuel cell can also be used as a measure that is indicative of the humidity within the fuel cell. The model and/or the high frequency resistance can be used in a closed-loop feedback system to control the operation of the fuel cell to maintain the humidification of the MEA and fuel cells within a desired range to achieve a desired fuel cell performance.
摘要:
An apparatus removes carbon monoxide (CO) from a hydrogen-rich gas stream in a hydrogen fuel cell system. CO fouls costly catalytic particles in the membrane electrode assemblies of proton exchange membrane (PEM) fuel cells. A vessel houses a carbon monoxide adsorbent. The vessel may be a rotating pressure swing adsorber. A water gas shift reactor is upstream of the rotating pressure swing adsorber. The water gas shift reactor may include a second adsorbent adapted to adsorb carbon monoxide at low temperatures and to desorb carbon monoxide at high temperatures. The apparatus advantageously eliminates the use of a preferential oxidation (PROX) reactor, by providing an apparatus which incorporates CO adsorption in the place of the PROX reactor. This cleans up carbon monoxide without hydrogen consumption and the concomitant, undesirable excess low grade heat generation. The present invention reduces start-up duration, and improves overall fuel processor efficiency during normal operation.
摘要:
The present invention relates to controlled staged rich combustion throughout a fuel processing system in order to improve start up performance. Multiple stages of air injection are used to burn rich combustion products within each component to provide direct heating thereof. During the start up cycle, the fluid temperature entering each reactor is increased and each component is heated to its operating temperature in parallel. The controlled staged rich combustion eliminates the load imposed upon a combustor within the system during the start up cycle. Thus, each of the components within the fuel processing system may be optimized for an operational mode rather than a start up mode.
摘要:
A fuel processor system capable of circulating fuel processor system gases, such as reformate, anode exhaust, and/or combustor exhaust, through the fuel processor to provide a number of distinct advantages. The fuel processor system having a plurality of fuel cells discharging an H2-containing anode effluent and an O2-containing cathode effluent. A fuel processor is also provided for converting a hydrogen-containing fuel to H2-containing reformate for fueling the plurality of fuel cells. A catalytic combustor is positioned in series downstream from the plurality of fuel cells and a vaporizer reactor is coupled to the catalytic combustor. A bypass passage is finally provided that interconnects an outlet of at least one of the group consisting of the fuel processor, the plurality of fuel cells, the catalytic combustor, and the vaporizer reactor to the inlet of the fuel processor. The bypass passage is operable to circulate a fuel processor system gas to the inlet of the fuel processor.
摘要:
A fuel processor for rapid start and operational control. The fuel processor includes a reformer, a shift reactor, and a preferential oxidation reactor for deriving hydrogen for use in creating electricity in a plurality of H2—O2 fuel cells. A heating and cooling mechanism is coupled to at least the shift reactor for controlling the critical temperature operation of the shift reactor without the need for a separate cooling loop. This heating and cooling mechanism produces or removes thermal energy as a product of the temperature of the combustion of air and fuel. Anode effluent and cathode effluent or air are used to control the temperature output of the heating mechanism. A vaporizer is provided that heats the PrOx reactor to operating temperature.
摘要:
An improved fuel processor thermal management system for use with a fuel cell is disclosed. The process includes supplying an air stream and a fuel stream into a auto thermal reactor (ATR) and forming reformate gas therein. Then, preferentially oxidizing the reformate gas and the air stream in the preferential oxidizer reactor (PrOx). The temperature of the preferential oxidizer reaction is controlled with a water stream by vaporizing the water stream to form a first portion of vaporized water. Then, reacting the air stream with the reformate gas exiting the PrOx is reached in a fuel cell to form an anode exhaust stream which is subsequently combined with the air stream to heat the water stream to form a second portion of vaporized water. The first portion of vaporized water and the second portion of vaporized water form a steam fluid. The steam fluid heats the auto thermal reactor and the air stream prior to entering the ATR and the reformate gas prior to entering the water shift gas reactor (WGS) to control the temperature of the reformate gas.
摘要:
A fuel processor control system for a fuel cell stack includes water and fuel metering devices that control water and fuel provided to the fuel processor. An air flow rate sensor generates an air flow rate signal based on air flowing from a compressor to the fuel processor. A valve is located between the fuel processor and the fuel cell stack. A controller controls the valve and the water and fuel metering devices based on the air flow rate sensor. Other feedback signals such as stack voltage, stack cell voltage variation, pressure differential across the valve, and mass flow rate between the valve and the fuel cell stack can augment or be substituted for the air flow rate feedback signal. The fuel processor can be a partial oxidation reformer a steam reforming reactor, an auto thermal reformer or any combination thereof. The system may also include a water as shift reactor and a preferential oxidation reactor for carbon monoxide reduction.
摘要:
A system and method for correcting an estimation of nitrogen in an anode side of a fuel cell stack. The system includes a fuel cell stack and a pressure sensor for measuring pressure in an anode sub-system. The system also includes a controller configured to control the estimation of nitrogen permeation from the cathode side to the anode side of the stack, where the controller determines if the pressure in the anode sub-system equilibrates with atmospheric pressure in a shorter period of time after shutdown compared to the time necessary for the anode sub-system to reach approximately atmospheric pressure after a previous shutdown or calibrated time value, and corrects the estimation of nitrogen in the anode side of the stack if the pressure equilibrates in a shorter period of time.
摘要:
A passive water drain for removal of water from a fuel cell system is disclosed, the drain including a main body having a cavity formed therein, an interior element, and a hydrophilic porous media. The passive water drain is adapted to simplify the anode reactant recycler, eliminate the need for bypass valve systems used to remove water from the cathode exhaust, and eliminate the need for condensate draining systems used for compressed air entering the cathode.