Abstract: An object of the present invention is to provide a fuel cell system in which a noise and a vibration of a compressor can be suppressed. In order to achieve the above object, the present invention provides a fuel cell system including a fuel cell; a compressor for supplying an oxidant gas to the fuel cell, having a first rotational speed region within which as a rotational speed increases, a noise becomes greater than a predetermined value, and a second rotational speed region within which as the rotational speed increases, the noise becomes equal to or less than the predetermined value; and a compressor controller for controlling the compressor by calculating a command rotational speed for commanding the compressor based on a required amount of power generation.

Abstract: The present invention provides a fuel cell system and a control method thereof that performs a scavenging process when the fuel cell is stopped, whereby stable electrical power production is ensured after startup, and faster startup is possible. The fuel cell system performs the scavenging process in which scavenging gas is supplied into an anode gas system when the fuel cell is stopped. When a startup request for the fuel cell is detected while the anode scavenging process is being performed, the concentration of hydrogen in the anode gas is detected, and then whether to continue the anode scavenging process and prohibit the fuel cell from starting, or to suspend the anode scavenging process and allow the fuel cell to start is determined based on this detected concentration of hydrogen in the anode gas system.

Abstract: A fuel cell system and an idle stop controlling method for the fuel cell system. The fuel cell system includes: a fuel gas supply means for supplying fuel gas; an oxidant gas supply means for supplying oxidant gas; a fuel cell to which the fuel gas and the oxidant gas are supplied for generation of electricity; an idle stop means for stopping generation of electricity by the fuel cell to perform idle stop; and an unstable state detection means for detecting whether the generation of electricity by the fuel cell is unstable. If the unstable state detection means detects that generation of electricity by the fuel cell is unstable, idle stop by the idle stop means is prohibited so that the fuel cell continues to generate electricity.

Abstract: A fuel cell system is provided with a fuel cell that supplies fuel gas to an anode electrode and that supplies oxidant gas to a cathode electrode to generate electric power; a scavenging gas supply device that scavenges the inside of the fuel cell; a temperature detection device that detects a temperature of the inside of the fuel cell; a deterioration countermeasure scavenging device that executes deterioration countermeasure scavenging by the scavenging gas supply device and replaces the accumulated gas accumulated in the anode electrode with the scavenging gas; and a sub-zero countermeasure scavenging device that executes sub-zero countermeasure scavenging with a greater flow volume than the scavenging gas supplied during the deterioration countermeasure scavenging and to discharge the generated water in the inside of the fuel cell.

Abstract: The fuel cell system is equipped with a fuel cell for generating power by a reaction of fuel and oxidizer gases, a fuel gas flow passage for passing the fuel gas, an oxidizer gas flow passage for passing the oxidizer gas, a sweeping gas supply mechanism for sweeping any of the fuel and oxidizer gas flow passages by a sweeping gas, a sweeping determination mechanism for determining whether to perform sweeping by the sweeping gas supply mechanism, when receiving a stop request for stopping the fuel cell system, a pressure reduction mechanism for reducing a pressure within one of the flow passages lower than when determined not to perform the sweeping, when determined to perform the sweeping by the sweeping determination mechanism, and an actuation mechanism for actuating the sweeping gas supply mechanism after the pressure within the flow passage is reduced by the pressure reduction mechanism.

Abstract: A controller of a fuel cell system includes an anode gas replacement apparatus, a stoppage time detection apparatus, and a cathode gas flow rate control apparatus. The anode gas replacement apparatus replaces hydrogen in an anode gas channel using an anode gas supply apparatus. The stoppage time detection apparatus detects a stoppage time during which operation of the fuel cell stack is stopped. When the anode gas replacement apparatus replaces the hydrogen, the cathode gas flow rate control apparatus changes the flow rate of the cathode gas supplied from the cathode gas supply apparatus depending on the stoppage time.

Abstract: The following control is performed. During startup of a fuel cell 1, a fuel gas is supplied to an anode 1b of the fuel cell 1 and an oxidant gas is supplied to a cathode 1c of the fuel cell 1, thereby starting power generation. Fuel gas externally emitted from the abode 1b is diluted with an oxidant gas externally emitted from the cathode 1c. From a start to end of discharge of a fuel gas from the anode 1b, a flow rate required for dilution of the oxidant gas, and a flow rate required for an external output, being calculated on the basis of the power requested for the fuel cell 1, are respectively calculated. The flow rate required for dilution and the flow rate required for an external output are compared, and a larger flow rate is set as a flow rate of the oxidant gas.

Abstract: A reaction gas supply apparatus for a fuel cell is able to adapt to various kinds of operating states, and can provide improved responsiveness with respect to a required output. The apparatus has: a compressor 2 that supplies pressurized air to a cathode electrode of a fuel cell 1; a hydrogen supply device 30 that supplies hydrogen to an anode electrode of the fuel cell 1; a control device 10 that regulates the pressure of the cathode electrode by controlling the compressor 2 according to an operating state of the fuel cell 1; and a regulator 5 that is applied with the air pressure of the cathode electrode as a reference pressure, and regulates the supply pressure to the anode electrode based on this air pressure. Moreover there is provided a pressure regulator 39 that is capable of regulating the reference pressure that is applied to the regulator 5, by discharging air from an air flow passage for the air pressure that is applied to the regulator 5.

Abstract: A fuel cell system includes: a fuel cell in which electrical power generation is performed through chemical reactions of reaction gases being supplied thereto; a discharge path through which the reaction gases are discharged; a discharge valve provided on the discharge path and operated for discharging the reaction gases through the discharge path; an opening condition monitoring device for continuously monitoring a demanded opening condition of the discharge valve; and an opening condition renewing device for renewing the demanded opening condition of the discharge valve depending on the demanded opening condition of the discharge valve detected by the opening condition monitoring device when opening of the discharge valve is demanded. Opening of the discharge valve is controlled depending on the latest demanded opening condition which has been renewed by the opening condition renewing device.

Abstract: A fuel cell system has a fuel cell, a fuel supply device, a gas discharge valve, a voltage detecting device and a control device. The fuel supply device supplies a fuel gas to the fuel cell. The gas discharge valve discharges the fuel gas into an external environment. The voltage detecting device detects an output voltage of the fuel cell. The control device controls a discharging process when a request for starting the fuel cell is given. The discharging process includes introducing the fuel gas from the fuel supply device into a predetermined passage, opening the gas discharge valve and discharging residuals staying in the passage into the external environment. When the control device receives the request and determines that the output voltage has reached a first threshold before the discharging process has not been completed, the control device starts power generation irrespective of completion of the discharging process.

Abstract: A current limiting system for fuel cells includes a target current limit value setting device which sets a target current limit value for limiting the generated current taken out from the fuel cell stack in accordance with the cell voltage, and a current limit value setting device which sets a current limit value by replacing a present current limit value with the target current limit value when a difference between the present current limit value and the generated current value becomes smaller than a first predetermined value. The system also includes an output device which outputs the current limit value either to a current limiter for limiting the generated current in accordance with the current limit value or to an electric power consumption controller for controlling electric power consumption of loads that consume the generated current.

Abstract: A fuel cell system is equipped with a fuel cell for generating power by an electrochemical reaction of a fuel gas and an oxidizer gas, a fuel gas supply mechanism for supplying the fuel gas to the fuel cell, a supply amount adjustment mechanism for adjusting a supply amount of the fuel gas, a fuel gas flow passage for passing the fuel gas, a purge valve for purging a gas within the fuel gas flow passage outside, and a control mechanism for opening the purge valve when a stop request of the fuel cell is output, wherein when an activation request of the fuel cell is output, the control mechanism controls the supply amount adjustment mechanism so that a pressure within the fuel gas flow passage becomes smaller than a minimum pressure in a normal power generation and larger than an atmospheric pressure.

Abstract: A failure determination device for a cell voltage monitor which detects cell voltages of a plurality of single cells comprising a fuel cell stack comprises: a memory for storing cell voltages detected by the cell voltage monitor; a minimum value determination unit for determining whether or not a present cell voltage which the cell voltage monitor detects is equal to or lower than a minimum value cell voltage which is in a detectable range of the cell voltage monitor; a failure determination unit for determining that the cell voltage monitor has a failure when the minimum value determination unit determines that the present cell voltage is equal to or lower than the minimum value cell voltage, and a cell voltage detected by the cell voltage monitor in the past and stored in the memory is greater than a determination cell voltage.

Abstract: A start-up method for a fuel cell system that includes a fuel cell that carries out power generation by the electrochemical reaction between a fuel gas and the oxygen gas in the air; a fuel gas discharge path and a fuel gas supply path that are connected to the fuel cell; a fuel gas circulation path in which the fuel gas discharge path merges with the fuel gas supply path; and a purge valve provided on the fuel gas circulation path in order to discharge the circulating fuel gas from the fuel gas circulation path. The method includes the steps of opening the purge valve at the same time that the fuel gas is supplied to the fuel cell and replacing the nitrogen gas that originates in the air and is present in the fuel gas circulation path by fuel gas; and closing the purge valve after the nitrogen gas in the fuel gas circulation path has been replaced by the fuel gas.

Abstract: A fuel cell system includes: a fuel cell which generates electrical power from a chemical reaction of a reaction gas; a discharge path for discharging the reaction gas supplied to the fuel cell; a discharge valve which is provided in the discharge path and discharges the reaction gas from the discharge path; and valve control units for controlling opening of the discharge valve, wherein the valve control units are adapted such that, since the discharge valve has been opened by a valve open command issued by one of the valve control units, the valve control units prohibit the discharge valve from being opened by a valve open command issued by any of the other valve control units until a predetermined time period elapses.

Abstract: A fuel cell system of the present invention is mounted on a moving object and is equipped with a fuel cell for generating power by chemically reacting a fuel gas supplied to an anode and an oxidizer gas supplied to a cathode; a cooling mechanism for cooling the fuel cell by radiating heat of a refrigerant circulating in the fuel cell into an atmosphere; a speed detection mechanism for detecting a moving speed of the moving object; an outside air temperature detection mechanism for detecting an outside air temperature; a cooling amount estimation mechanism for estimating a cooling amount of the fuel cell by the cooling mechanism, based on the moving speed and the outside air temperature; and an upper limit value set mechanism for setting an upper limit value of a power generation current, based on an estimation result of the cooling amount estimation mechanism.

Abstract: A start-up method for a fuel cell system that includes a fuel cell that carries out power generation by the electrochemical reaction between a fuel gas and the oxygen gas in the air; a fuel gas discharge path and a fuel gas supply path that are connected to the fuel cell; a fuel gas circulation path in which the fuel gas discharge path merges with the fuel gas supply path; and a purge valve provided on the fuel gas circulation path in order to discharge the circulating fuel gas from the fuel gas circulation path. The method includes the steps of opening the purge valve at the same time that the fuel gas is supplied to the fuel cell and replacing the nitrogen gas that originates in the air and is present in the fuel gas circulation path by fuel gas; and closing the purge valve after the nitrogen gas in the fuel gas circulation path has been replaced by the fuel gas.

Abstract: A fuel cell system comprises a fuel cell, a hydrogen discharge valve for discharging hydrogen from the fuel cell under a predetermined condition, a hydrogen concentration reduction device for reducing the concentration of hydrogen discharged from the hydrogen discharge valve, a hydrogen sensor for detecting an instantaneous hydrogen concentration of a gas processed by the hydrogen concentration reduction device and an average hydrogen concentration calculating unit for calculating an average hydrogen concentration per hour of a gas processed by the hydrogen concentration reduction device, wherein a hydrogen discharge from the fuel cell by the hydrogen discharge valve is prohibited in the event that an instantaneous hydrogen concentration detected by the hydrogen sensor exceeds a first threshold, or in the event that an average hydrogen concentration calculated by the average hydrogen concentration calculating unit exceeds a second threshold which is lower than the first threshold.

Abstract: A fuel cell system includes a diluting apparatus which comprises a first introducing portion, a second introducing portion and an inner space and a discharge portion, and a control unit which comprises discharged fuel gas quantity detection means, a current remaining fuel gas detection means and a purge treatment means. In this fuel cell system purging the fuel gas is controlled calculating a current remaining fuel gas quantity in the inner space based on a fuel gas quantity introduced into the inner space, a flow rate of an oxidizing off-gas, a ventilation rate and a flow rate of a diluting gas.

Abstract: A hydrogen purge control apparatus includes a fuel cell stack from which hydrogen is purged as necessary, a purged hydrogen dilution device which is disposed downstream of the fuel cell stack, and which has a chamber formed therein, a first inlet for purged hydrogen, a second inlet for air, and an outlet for diluted hydrogen, a regulator which is disposed between the fuel cell stack and the first inlet, and which is provided for regulating an amount of the purged hydrogen flowing into the purged hydrogen dilution device, and a control unit having a hydrogen concentration estimating section that is configured to estimate the hydrogen concentration at the outlet of the purged hydrogen dilution device based on an operating state of the fuel cell stack. The regulator is operated by the control unit depending on the hydrogen concentration estimated by the hydrogen concentration estimating section.