Abstract: A fuel cell system is provided that can suppress the degradation of the MEA and simultaneously assure the merchantability. The fuel cell system 1 includes: a fuel cell 10 that generates electric power by reacting hydrogen gas and oxidant gas; a temperature sensor 103 that detects the temperature of the fuel cell 10; a voltage lower limit calculation portion 31 that sets the voltage threshold to limit the output of the fuel cell 10 based on the temperature detected of the fuel cell 10; a current upper limit calculation portion 32 and the current limiting portion 33 that limits the output of the fuel cell in a case where the voltage generated by the fuel cell 10 is lower than the voltage threshold.

Abstract: A fuel cell system including: a fuel cell which generates electrical power through the reaction of a reaction gas; a reaction gas supply device which supplies the reaction gas to the fuel cell; a cooling device which cools the fuel cell by circulating a coolant through the fuel cell; a fuel cell operating temperature output device which outputs a maximum temperature inside the fuel cell as an operating temperature of the fuel cell; and a fuel cell temperature adjustment device which adjusts a temperature inside the fuel cell so that the operating temperature inside the fuel cell is less than a preset upper temperature limit.

Abstract: A fuel cell system comprising: an anode gas flow path supplied with an anode gas; a cathode gas flow path supplied with a cathode gas; a fuel cell generating electricity by the anode gas being supplied to the anode gas flow path and the cathode gas being supplied to the cathode gas flow path; an anode gas supplying unit supplying the anode gas to the anode gas flow path; a blowdown valve ejecting fluid from inside the anode gas flow path towards an exterior; and a control unit which controls the anode gas supplying unit and the blowdown valve, supplies the anode gas from the anode gas supplying unit to the anode gas flow path, and performs a periodic fluid substitution by opening the blowdown valve periodically, wherein the control unit comprises a low temperature condition determination unit.

Abstract: An object of the present invention is to provide a fuel cell system capable of starting below freezing point without increasing the size of the diluter. The fuel cell system 1 comprises an OCV purge execution unit 42 replacing gas retained in a fuel cell 10 by supplying additional anode gas from a supply device 20 to the fuel cell 10 when starting up the fuel cell. In addition, the fuel cell system 1 comprises a low temperature startup determination unit 41 determining whether to perform low temperature startup or normal startup on the fuel cell 10. The OCV purge execution unit 42 decreases the pressure of additional anode gas supplied from the supply device 20 and increases the total replacing amount of gas retained in the fuel cell 10 in a case of performing low temperature startup, as compared with a case of performing normal startup.

Abstract: A fuel cell system and method comprising a fuel cell stack formed by stacking fuel cells, a high voltage energy storage capable of being directly coupled to the fuel cell stack, a DC-DC converter connected to the fuel cell stack and the energy storage, a load operated by consuming at least electrical energy generated by the fuel cell stack or electrical energy discharged from the energy storage, a fuel cell warming up control unit for warming up the fuel cell stack, and a voltage adjustment unit for implementing voltage control to control the output voltage of the fuel cell stack to become equal to, or higher than the terminal voltage of the energy storage, at the time of warming up the fuel cell stack.

Abstract: A fuel cell system includes a fuel cell, a circulation path, a water reservoir, a water level detector, a water discharger and a controller. The fuel cell generates electric power using fuel gas supplied to an anode and oxidant gas supplied to a cathode. Off-gas discharged from the fuel cell is returned to the fuel cell again through the circulation path. The water reservoir is disposed in the circulation path and stores water separated from the off-gas. During monitoring after stop of the fuel cell system or at startup of the fuel cell system, the controller operates the water discharger to discharge the water stored in the water reservoir when the controller determines that a level of the water detected or estimated by the water level detector is equal to or higher than a predetermined reference water level.

Abstract: A fuel cell system which includes: a fuel cell having a fuel gas flow path and an oxidant gas flow path and generating electricity by being supplied a fuel gas to the fuel gas flow path and an oxidant gas to the oxidant gas flow path; fuel gas supplying means; a discharge valve; fuel gas exchange means for exchanging an atmosphere inside the fuel gas flow path for the fuel gas at a starting of the system; and cold start determination means for determining whether to conduct or not to conduct the cold start of the system, wherein when the cold start determination means determines to conduct the cold start, the cold start determination means increases a total discharge amount of a gas to be discharged for exchanging the atmosphere inside the fuel gas flow path for the fuel gas, and thereby increases a fuel gas concentration in the fuel gas flow path.

Abstract: A fuel-cell system 1 includes: a fuel cell 13 configured to generate electricity through reaction between hydrogen gas and air; a compressor 12 configured to supply air as a scavenging gas to a reactant gas path 13a of the fuel cell 13; a control part 18 configured to control an amount of air supplied from the compressor 12 to the fuel cell 13 to perform scavenging of the fuel cell 13; and pressure sensors P1 and P2 configured to monitor a pressure drop in the reactant gas path 13a of the fuel cell 13. The control part 18 controls an amount of supplied air so as to keep the pressure drop in the reactant gas path 13a substantially constant when the fuel cell 13 is scavenged. With this configuration, residual water can be suitably purged from the fuel cell while energy consumption is suppressed.

Abstract: A fuel cell system comprising: an anode gas flow path supplied with an anode gas; a cathode gas flow path supplied with a cathode gas; a fuel cell generating electricity by the anode gas being supplied to the anode gas flow path and the cathode gas being supplied to the cathode gas flow path; an anode gas supplying unit supplying the anode gas to the anode gas flow path; a blowdown valve ejecting fluid from inside the anode gas flow path towards an exterior; and a control unit which controls the anode gas supplying unit and the blowdown valve, supplies the anode gas from the anode gas supplying unit to the anode gas flow path, and performs a periodic fluid substitution by opening the blowdown valve periodically, wherein the control unit comprises a low temperature condition determination unit.

Abstract: A fuel cell system comprising: an anode gas circulation path comprising an anode gas supplying path and an anode gas ejection path; a fuel cell; a blowdown valve; and a control unit controlling the blowdown valve, wherein the control unit comprises a freeze estimation unit estimating whether the anode gas circulation path is likely to freeze, a pressure reduction unit reducing a pressure of the anode gas circulation path, and a pressure condition confirmation unit confirming a pressure of the anode gas circulation path; and when the freeze estimation unit estimates a freezing when the fuel cell stops generating electricity, the blowdown valve is closed, a pressure of the anode gas circulation path is reduced by the pressure reduction unit, and, the blowdown valve is opened after the pressure condition confirmation unit confirms that a pressure of the anode gas circulation path reaches a predetermined pressure less than or equal to an atmospheric pressure, thereby moving a moisture inside the anode gas circula

Abstract: This fuel cell system is equipped with a fuel cell having a reaction gas flow passage, generating power by the reaction gas being supplied to the reaction gas flow passage, having a refrigerant flow passage, and cooled by the refrigerant being supplied to the refrigerant flow passage; a reaction gas supply device for supplying the reaction gas to the reaction gas flow passage; a refrigerant supply device for supplying the refrigerant to the refrigerant flow passage; a refrigerant supply restriction device for restricting a refrigerant supply amount to the refrigerant flow passage; and a controller for controlling the refrigerant supply restriction device, wherein the reaction gas refrigerant supply devices have a drive device in common and are integrally driven, and wherein when warming up the fuel cell, the controller controls the refrigerant supply restriction device and reduces the refrigerant supply amount to the refrigerant flow passage.

Abstract: A fuel cell system and a method for scavenging it are provided. The fuel cell system includes a fuel cell, a fuel gas passage, an oxidant gas passage, a communicating passage, a communicating valve, a monitoring device, a valve controller, a scavenging device and a computing device. The monitoring device monitors a state transition of the fuel cell after a termination of power generation. The valve controller opens the communicating valve when a signal indicative of the state transition meets a predetermined criterion. The scavenging device includes a first scavenging device for the oxidant gas passage, and a second scavenging device for the fuel gas passage. The computing device computes an amount of the oxidant gas required for scavenging according to a system shut off time. The scavenging device conducts scavenging with the amount of the oxidant gas obtained by the computing device.

Abstract: A fuel cell system comprises a fuel cell stack, a cell voltage monitor, a hydrogen tank, a hydrogen supply channel, an ejector, a hydrogen off-gas channel, a purge valve, a compressor, an air supply channel, a pressure control unit for controlling air pressure, a pilot pressure input channel branching off from the air supply channel and inputting the air pressure to the ejector as pilot pressure, and a control unit for controlling the purge valve and the pressure control unit. The ejector includes a pressure control mechanism which increases the ejector's secondary-side pressure by increasing the area of the nozzle's ejecting hole when the pilot pressure input from the pilot pressure input channel rises. When electricity generation status of the fuel cell stack is judged to be poor, the control unit opens the purge valve after raising the air pressure and the pilot pressure by using the pressure control unit.

Abstract: A fuel cell system includes a fuel cell stack for power generation by electrochemical reactions of a fuel gas and an oxygen-containing gas, a high voltage energy storage capable of storing and discharging electrical energy generated by power generation of the fuel cell stack, and capable of being directly coupled to the fuel cell stack, a group of loads consuming at least electrical energy generated by the fuel cell stack or electrical energy discharged from the high voltage energy storage, and an auxiliary device control unit for reducing an amount of electrical energy remaining in the energy storage to a predetermined value by any of the group of loads, before starting power generation of the fuel cell stack.

Abstract: This invention provides a fuel cell system preventing from a first valve such as a purge valve exhausting gas outside. The fuel cell system includes a fuel cell stack, an anode off-gas channel, a purge valve and a scavenging gas exhaust valve connected to the anode off-gas channel and exhausting gas inside the anode off-gas channel outside, a drain valve connected to the anode off-gas channel arranged in an upstream side of a connecting point of the purge valve and the scavenging gas exhaust valve and exhausting the moisture exhausted from the anode channel 12 to the anode off-gas channel, and ECU. The control unit is designed to open only the drain valve in a closed condition of the purge valve and the scavenging gas exhaust valve, after the anode off-gas channel is filled with gas in a closed condition of the purge valve, the scavenging gas exhaust valve, and the drain valve during the stop of power generation of the fuel cell stack.

Abstract: When it is detected that the ignition switch is turned off a short period of time after the ignition switch turned on at the temperature below the freezing point, the charge threshold of a capacitor is changed to a larger charge threshold C for increasing the amount of electrical energy charged in the capacitor based on the charge threshold C. The capacitor is used for performing a scavenging process for a sufficient period of time. At the time of starting operation of the fuel cell system at the temperature below the freezing point the next time, using the electrical energy of the capacitor, a fuel cell is warmed rapidly by a heater or the like to start operation of the fuel cell system.

Abstract: A fuel cell system draining water in a air-and-water separator includes: a fuel cell stack; a hydrogen-circulating line; an air-and-water separator; a drain unit including a drain valve for draining the water stored in the air-and-water separator; a drain-control unit for controlling the drain unit; a determining unit for determining whether or not the drain-control unit decides that the drain unit should be opened; a frozen-state-presuming unit presuming whether or not the drain unit is frozen; and a thawing-state-determining unit determining whether or not the drain unit is thawed, wherein the drain-control unit controls the drain unit so that a greater amount of the water is drained than a water drained in an ordinary state process which presumes that the drain unit is not frozen, after the frozen-state-presuming unit presumes that the drain unit is frozen and when the thawing-state-determining unit determines mat the drain unit is thawed.

Abstract: A reaction gas is supplied to a cathode side of a fuel cell at a flow rate higher than that for a usual operation of the fuel cell to thaw the fuel cell system at startup in a freezing state of the system when the system has experienced a temperature lower than an operation temperature of an anode off-gas. A thawing state of the system is detected on the basis of at least two of temperatures of the anode off-gas, a cathode off gas, and a radiator liquid of the fuel cell to control supplying the reaction gas to the cathode side at a usual operation flow rate. An actual increase rate of the temperature of the anode off-gas is obtained and an increase rate of the temperature of the anode off-gas is calculated from the self-heating value to be compared to determine the thawing state.

Abstract: An object of the present invention is to provide a fuel cell system capable of starting below freezing point without increasing the size of the diluter. The fuel cell system 1 comprises an OCV purge execution unit 42 replacing gas retained in a fuel cell 10 by supplying additional anode gas from a supply device 20 to the fuel cell 10 when starting up the fuel cell. In addition, the fuel cell system 1 comprises a low temperature startup determination unit 41 determining whether to perform low temperature startup or normal startup on the fuel cell 10. The OCV purge execution unit 42 decreases the pressure of additional anode gas supplied from the supply device 20 and increases the total replacing amount of gas retained in the fuel cell 10 in a case of performing low temperature startup, as compared with a case of performing normal startup.

Abstract: A fuel cell system includes a fuel cell stack formed by stacking fuel cells, a high voltage energy storage capable of being directly coupled to the fuel cell stack, a DC-DC converter connected to the fuel cell stack and the energy storage, a load operated by consuming at least electrical energy generated by the fuel cell stack or electrical energy discharged from the energy storage, a fuel cell warming up control unit for warming up the fuel cell stack, and a voltage adjustment unit for implementing voltage control to control the output voltage of the fuel cell stack to become equal to, or higher than the terminal voltage of the energy storage, at the time of warming up the fuel cell stack.