Abstract: An object is to provide a fuel cell system capable of suitably avoiding damage to the equipment caused by abnormally high pressure of fuel gas and appropriately discharge fuel gas at a safe concentration to the outside. The fuel cell system (1) includes a fuel gas passage (38) that feeds fuel gas to a fuel cell (2), a relief valve (57) that is provided in the fuel gas passage (38) and discharges fuel gas to the outside when fuel gas in the fuel gas passage (38) is pressurized to a predetermined pressure or higher, an external discharge passage (59) that is provided on the gas discharge side of the relief valve (57), and a gas processing device (19) that is provided in the external discharge passage (59) and reduces the concentration of fuel gas discharged from the relief valve (57).

Abstract: A fuel cell system that generates electricity using an electrochemical reaction of fuel gas and oxidizing gas, having: a pressure adjustment valve which is provided on a fuel gas supply path for conducting the fuel gas from a fuel gas supply source to a fuel cell and which adjusts the supply gas pressure of the fuel gas; a degree of opening adjustment valve provided downstream of the pressure adjustment valve on the fuel gas supply path, the degree of opening thereof being set in stages or continuously in accordance with a degree of opening signal; and control means that adjusts the degree of opening adjustment signal in accordance with the operating condition of the fuel cell system and controls the state quantity of fuel gas supplied to the fuel cell to a target quantity.

Abstract: A fuel cell system comprises a fuel cell, a supply flow passage for flowing a fuel gas supplied from a fuel supply source to the fuel cell, a variable gas supply device for regulating the state of the gas on the upstream side of the supply flow passage to supply the gas to the downstream side, a discharge flow passage for flowing a fuel off gas discharged from the fuel cell, a discharge valve for discharging the gas from the discharge flow passage to the exterior, and a control part for closing the discharge valve when the discharge amount of the gas calculated while the discharge valve is opened exceeds a predetermined target discharge amount. The control part stops the gas supply from the variable gas supply device and simultaneously closes the discharge valve, when the discharge amount of the gas calculated while the discharge valve is opened exceeds the target discharge amount.

Abstract: The fuel cell system is provided which detects a freeze among specific components and portions thereof by evaluating various conditions upon starting operation of the fuel cell system. If a freeze is detected through those evaluations, the start of the system is prohibited in order to prevent some deterioration in the fuel cell system.

Abstract: A controllable range of an air flow rate and an air pressure in a fuel cell system is calculated from air flow rates and air pressures when the air back pressure valve is fully open and fully closed. A target generation current is calculated from an accelerator position or an auxiliary unit to calculate a target air flow rate and a target air pressure as target values. If the target values are outside the controllable range, it is judged whether the target values exceed an upper limit the controllable range, the target values are decreased onto the upper limit, and if no, the target values are increased onto the lower limit of the controllable range.

Abstract: A fuel supply manifold assembly (20) comprising a manifold (40), one or more supply inlet connections (42), pressure readers (44, 46), a manual turnoff (50), pressure-reducing devices (52,54), a pressure-relieving device (56), a flow-control device (60), and a delivery outlet port (62). The manifold (40) defines a flow path from the supply inlet connection(s) (42) to the delivery outlet port (62). The flow path passes through the pressure readers (44, 46), the manual turnoff (50), pressure-reducing devices (52,54), the pressure-relieving device (56), the flow-control device (60). When installing the fuel supply manifold assembly (20) at a fuel cell site, one inlet connection for each fuel source and one outlet connection is required. No separate connections, tubing, hoses, or other plumbing is required to integrate other the components into the fuel flow path to the anode side of the fuel cell stack.

Abstract: There is provided a fuel cell system including a supply port, a supply-side main flow path, a discharge-side main flow path, a plurality of branch flow paths, and a discharge port, wherein with respect to each of the branch flow paths, the magnitudes of flow path resistances of predetermined portions of the flow paths satisfy specified mutual relationships. Thereby, a fuel cell system is provided that can effectively expel impurity gas that resides/accumulates in a power generation cell, even at a small flow rate of low-pressure hydrogen gas.

Abstract: A fuel cell system including a fuel cell that generates electricity through an electrochemical reaction between a fuel gas and an oxidizing gas is provided with a gas supply unit that supplies each of the fuel gas and the oxidizing gas to an anode and a cathode of the fuel cell, respectively by quantity corresponding to a load, a gas permeation quantity estimation unit that estimates a gas permeation quantity of at least one of the fuel gas and the oxidizing gas between the anode and the cathode after the power generation performed by the fuel cell is stopped, and a correction unit that corrects a supply quantity of at least one of the fuel gas and the oxidizing gas each corresponding to the load in accordance with the estimated gas permeation quantity, which is to be supplied by the gas supply unit upon a subsequent start of power generation.

Abstract: For a fuel cell system, the flow rate and the pressure of the air flow supplied to the cathode side are controlled with the following procedure. First, air is supplied to the cathode at the flow rate and supply pressure required for generating electricity. In this state, the changing rate of the amount of formed water accumulated in the cathode is estimated based on the required electricity generation and the air flow rate. When the accumulated amount of formed water increases in a high rate, to avoid flooding, the cathode outlet regulation valve is intermittently opened to decrease the outlet gas pressure. Also, at a frequency less than that of the pressure decrease, the air flow rate is increased. By executing this operation, the increased air flow rate and the pressure difference between the cathode inlet and outlet, it is possible to promote discharge of the formed water with small loss of energy.

Abstract: A fuel cell system includes a fuel cell having an anode, a cathode, and an electrolyte membrane disposed therebetween. An oxidant gas supplying device supplies oxidant gas to the cathode, an oxidant gas backpressure regulating device regulates the pressure of the oxidant gas at the cathode according to a valve opening, and a pressure detecting device detects the oxidant gas pressure at the cathode. During a start-up fuel gas disposal process, a controller controls the oxidant gas supplying device to supply the oxidant gas at a standard oxidant gas flow, controls the valve opening of the oxidant gas backpressure regulating device to a first valve opening, and controls the valve opening of the oxidant gas backpressure regulating device to a second valve opening which is greater than the first valve opening when the oxidant gas pressure detected by the pressure detecting device reaches an elevation target pressure.

Abstract: A method for managing fuel cell power increases in a fuel cell system using an air flow feedback delay. The method comprises the steps of determining a required air mass flow rate at a predetermined point in the fuel cell system, determining an actual air mass flow at a predetermined point in the fuel cell system, calculating an air flow feedback delay as a function of the required air mass flow rate and the actual air mass flow, and delaying an external circuit from increasing current draw from the fuel cell stack by the magnitude of the air flow feedback delay.

Abstract: A method of controlling pressure of a fuel gas in a fuel cell stack is disclosed. The method includes establishing a specification for a fuel gas/oxidant gas delta pressure vs. time value, operating the fuel cell stack, monitoring the fuel gas/oxidant gas delta pressure vs. time value and reducing stress resulting from excessive pressure of the fuel gas by implementing at least one of the following: (1) inducing the fuel cell stack to convert excess fuel gas into electrical current; (2) shutting off supply of the fuel gas to the fuel cell stack; and (3) and raising an operating pressure of the fuel cell stack when the fuel gas/oxidant gas delta pressure vs. time value strays beyond the specification.

Abstract: A simulator is used for developing a solid oxide fuel cell (SOFC). Through the simulator, electrical characteristics of the SOFC are examined. Thus, with the simulator, cost for developing the SOFC is saved.

Abstract: Micro fuel cell systems whose performance is enhanced by an accurate fluid delivery system. The fluid delivery system improves reactant fluid provision to meet electrical output, while maintaining correct stoichiometries for chemical processing in a downstream reactor. The fluid delivery system includes a pressure source and a differential flow meter. The differential flow meter uses a flow restrictor and a sensor. The pressure source moves a fluid through the flow restrictor; the sensor detects differential pressure in the flow restrictor and outputs a signal that permits dynamic control of fluid flow, e.g., by controlling a pump.

Abstract: A PEM fuel cell power plant includes fuel cells, each of which has a cathode reactant flow field plate which is substantially impermeable to fluids, a coolant source, and a fluid permeable anode reactant flow field plate adjacent to said coolant source. The anode reactant flow field plates pass coolant from the coolant sources into the cells where the coolant is evaporated to cool the cells. The cathode flow field plates prevent reactant crossover between adjacent cells. By providing a single permeable plate for each cell in the power plant the amount of coolant present in the power plant at shut down is limited to a degree which does not require adjunct coolant purging components to remove coolant from the plates when the power plant is shut down during freezing ambient conditions. Thus the amount of residual frozen coolant in the power plant that forms in the plates during shut down in such freezing conditions will be limited.

Abstract: A method of operating a fuel cell stack is disclosed. The method includes operating the fuel cell stack in accordance with a predetermined profile of fuel gas/oxidant gas delta pressure vs. time, monitoring a fuel gas/oxidant gas delta pressure vs. time value of the fuel cell stack and adjusting pressure of the fuel gas by consuming excess quantities of the fuel gas in the fuel cell stack when the fuel gas/oxidant gas delta pressure vs. time value of the fuel cell stack exceeds the predetermined profile.

Abstract: A fuel cell system includes: a fuel cell which generates electricity by supplying hydrogen to an anode electrode, and a reaction gas to a cathode electrode, an anode gas supply device which supplies hydrogen to the anode electrode, and a cathode gas supply device which drives a compressor using electric power generated by the fuel cell, and supplies pressurized reaction gas to the cathode electrode. The fuel cell system further includes a target pressure setting device which sets a target value for cathode pressure of the fuel cell, a correction device which corrects the target value in accordance with atmospheric pressure, and a control device which controls the cathode pressure of the fuel cell to the corrected target value. Efficient electric power generation can be performed in accordance with the ambient environment.

Abstract: The present invention is a fuel cell system including a fuel cell, an injector which is provided in a hydrogen supply channel of the fuel cell and which adjusts a gas state of an upstream side of the hydrogen supply channel to supply a gas toward a downstream side, and a control device which drives and controls the injector. The control device controls an operation of the injector based on a driving state of an associated device including the fuel cell system 1.

Abstract: A fuel cell system (10, 200) includes an intake pipe (45, 46) that admits an introduction of oxidizing gas upstream of an oxidizing gas supply source that supplies the oxidizing gas to a fuel cell (20), and an exhaust pipe (51, 52, 221, 222) that discharges exhaust gas which contains a vapor generated at an oxygen electrode side through an operation of the fuel cell (20). The fuel cell system (10, 200) is provided with a circulating pipe (61, 62, 220) that connects the intake pipe and the exhaust pipe (51, 52, 221, 222), a circulating valve (60) that is provided in the circulating pipe and operated to adjust a flow rate of the exhaust gas supplied from the exhaust pipe (51, 52, 221, 222) to the intake pipe, and a pressure generating member that is provided in the exhaust pipe (51, 52, 221, 222) at a position at which the circulating pipe and the exhaust pipe (51, 52, 221, 222) are joined and generates a pressure that is higher than at least an atmospheric pressure.

Abstract: A fuel cell system including a fuel cell stack having a plurality of fuel cells is provided. An anode supply manifold and an anode exhaust manifold are in fluid communication with the anodes of the plurality of fuel cells. A first valve is in fluid communication with the anode supply manifold and a second valve is in fluid communication with the anode exhaust manifold. A pressure sensor is adapted to measure an anode pressure. In operation, the first valve and the second valve are controlled in response to the anode pressure, thereby militating against an undesired exhausting of an anode supply stream.

Abstract: The present application provides a technique prevents a regulator arranged on a gas supplying path that supplies gas to a fuel cell installed in a fuel cell system from functioning erroneously, by controlling the pressure increase within the upper stream side of the regulator. The fuel cell system includes a fuel cell, an oxide gas supplying path to supply oxide gas to the fuel cell, a fuel gas supplying path to supply fuel gas to the fuel cell, a secondary regulator arranged on the fuel supplying path, a bypass path communicating the upper stream side path of the secondary regulator with the lower stream side path of the secondary regulator, and a pressure controlling valve that is closed in a case where the pressure difference between the upper stream side path and the lower stream side path is less than a predetermined amount, and opened in a case where the pressure difference between the upper stream side path and the lower stream side path exceeds the predetermined amount.

Abstract: Provided is a fuel cell system that can achieve a stable power generation state of a fuel cell after the fuel cell returns from an intermittent operation to a normal operation. The fuel cell system has: a fuel cell; a fuel gas system having a fuel gas supply flow path for flowing fuel gas supplied from a fuel supply source to the fuel cell; a variable pressure regulating valve that variably regulates the pressure of gas flowing through the fuel gas supply flow path; and a purge valve for exhausting gas from the fuel gas system, and the fuel cell system exhausts impurities in the fuel gas system to the outside through the purge valve after the fuel cell shifts from a power generation suspended state to a power generation state.

Abstract: A pressure fluctuation parameter (for example, a statistical indicator such as a root-mean-square value) from a set of differential pressure measurements between the inlet and the outlet of a fuel cell reactant flow channel carrying vaporized water is used to define flooding onset. Vaporized water in the flow of gas (air) through the flow channels is controlled in response to the parameter. Benefits include efficient operation (i.e., minimized stoichiometry) and effective management of rapid power transients in a fuel cell.

Abstract: A fuel cell stack utilizes flow shifting of the anode reactant within the individual fuel cells of the fuel cell stack. The anode side of the fuel cells are separated into two or more flow fields. Anode reactant is supplied in varying quantities to the two flow fields so that anode reactant flowing through one of the flow fields is allowed to back flow into the other flow field and vice versa. The back flowing of anode reactant between the flow fields distributes nitrogen more evenly between the multiple flow fields in each of the fuel cells.

Abstract: Here is disclosed a fuel cell system comprising: a fuel cell; a fuel gas system which supplies a fuel gas to the fuel cell and circulates the gas discharged from the fuel cell; a purge valve which discharges the gas from the fuel gas system; and control means for controlling the opening/closing operation of the purge valve. The control means controls the opening/closing operation of the purge valve so that impurities partial pressure in the fuel gas system is constant in the entire load region.

Abstract: The present invention relates to a fuel cell system with a fluid supply element and/or fluid control element. The fuel cell system includes a fuel cell, an anode train, and a cathode train. The fluid supply element and fluid control elements are disposed within the anode train and/or the cathode train. A sensor for detecting pressure fluctuations and/or pressure peaks in a fluid supply train of the anode and/or the cathode is provided.