Abstract: The amount of fuel supplied to a fuel cell is set to a second set value Qm2 smaller than a first set value Qm1 determined based on a load. Then, an output current Ifcr of the fuel cell with the fuel supply amount set to the second set value Qm2 is detected. The output current Ifcr is compared with a reference value Iref for determining mild deterioration to determine whether the fuel cell has deteriorated from the comparison result. If a determination that the fuel cell has deteriorated is made, the fuel supply amount is reset to a third set value Qm3 larger than the second set value Qm2.

Abstract: An FC voltage increasing converter includes a plurality of converter parts having reactors. Regarding the first of the plurality of converter parts provided with a thermistor, the output starts to be limited when the temperature detected by the thermistor reaches a limitation starting temperature, which is obtained based on a reference heat-resistant temperature, which is obtained by subtracting an error of the thermistor from a specification heat-resistant temperature of each of the reactors. Meanwhile, regarding the second, third and fourth of the plurality of converter parts not provided with thermistors, the outputs start to be limited when the temperature detected by the thermistor reaches a limitation starting temperature obtained based on an allowable temperature, which is obtained by subtracting a characteristic-variation temperature of the reactor from the reference heat-resistant temperature of the reactor.

Abstract: A fuel cell system FCS includes a fuel cell FC, a motor ES4 connected to the fuel cell FC, an FC boost converter ES6 which raises the output voltage of the fuel cell FC to output the voltage to the motor ES4, an inverter ES3, a current sensor S2, and a controller EC which controls the fuel cell FC, the FC boost converter ES6 and the inverter ES3. The controller EC controls the inverter ES3 so as to raise the target output voltage of the inverter, when the current detected by the current sensor S2 exceeds a predetermined current threshold value.

Abstract: A fuel cell vehicle is controlled by performing a rate limiting control process for reducing electric power generated by a fuel cell to reduce a frequency at which a voltage generated by the fuel cell is equal to or higher than a predetermined voltage when electric power requested by a load is lowered, and changing a rotational speed of an air pump depending on the electric power requested by the load when the electric power generated by the fuel cell is reduced.

Abstract: A fuel cell has multiple cells, the multiple cells including a first cell having a first fuel gas flow path, and a second cell having a second fuel gas flow path and a sensor that measures a specific parameter value relating to a decrease in concentration of fuel gas in the second fuel gas flow path.

Abstract: A fuel cell system is provided that can establish, for a long time period, a stack to an idling stop state. The fuel cell system includes: an idling stop control means for setting the stack to an idling stop state by, decreasing both a supplied amount of air to the stack and generated electric current produced from the stack to less than during the idling power generation; and a discharge valve control means for determining whether there is a necessity to discharge nitrogen or generated water inside of the anode system, and for opening the purge valve or drain valve in a case of there being a necessity. The discharge valve control means shortens valve open times (PO2, DO2) of the purge valve and drain valve during idling stop to less than the valve open times (PO1, DO1) thereof during idling power generation.

Abstract: A system and method for determining the maximum allowed stack current limit rate for a fuel cell stack that considers cell voltage. The method includes estimating a fuel cell stack voltage based on a fuel cell resistance value, stack variables and a current request signal. The fuel cell resistance value can be modeled based on stack temperature and stack relative humidity. The stack variables can include exchange current density and mass transfer coefficient. The method then uses the estimated fuel cell voltage and a look-up table based on estimated voltage to determine a current rate limit value for changing the current of the stack. The method then adds the current rate limit value and the current request signal to obtain the current set-point.

Abstract: The present invention is directed to a solid oxide fuel cell system with a load following function. The system sets a command power value, based on the amount of load, and instructs an inverter to achieve a permitted power value corresponding to the command power value, which is a permitted amount of power to be extracted from the fuel cell system. The system also changes an amount of change per unit time in the next inverter permitted power value.

Abstract: A power request controller that prevents a power request signal to a fuel cell stack controller from providing more compressor air and hydrogen gas than is necessary to meet the current power demands of the vehicle. The stack controller generates a signal of the available current from the fuel cell stack. This signal and the measured current actually being drawn from the stack are received by a proportional-integral (P-I) controller in the power request controller. If the available stack current is significantly greater than the stack current being used, the P-I controller will provide an output signal that reduces the power request signal to the stack controller so that the current produced by the stack and the current being drawn from the stack are substantially the same. A transient detector turns off the P-I controller so that it does not reduce the power request signal during an up-power transient.

Abstract: A control method of replenishing anode fuel for DMFC system is provided. The DMFC system includes at least a fuel cell, a cathode humidity-holding layer, a fuel distribution unit, a control unit, a liquid fuel replenishment device, a fuel storage region, and a temperature detecting device. The temperature detecting device is for detecting an actual temperature of the fuel cell. The control method of replenishing anode fuel includes utilizing the control unit to adjust a fuel replenishment amount supplied from the liquid fuel replenishment device. The fuel replenishment amount is the sum of a basic replenishment amount and a replenishment amount for temperature correction. The basic replenishment amount is a function of actual discharge current of the fuel cell. The replenishment amount for temperature correction is a function of the difference between the actual temperature of the fuel cell and the target temperature.

Abstract: An apparatus for managing a battery pack for a vehicle includes a temperature measurement module for measuring temperature of the battery pack; a current measurement module for measuring a charge/discharge current of the battery pack when the measured temperature is not within a predetermined temperature range; a time measurement module for measuring the time while the measured charge/discharge current is over a predetermined current value; a storage module for accumulating and storing the measured time; and a control module for determining a state of the battery pack according to the accumulated and stored time and providing the state information to a user.

Abstract: An example method of controlling a fuel cell power plant based on provided power includes selectively varying an electrical resistance of the variable resistive device responsive to at least one of a power provided by the fuel cell power plant, a current provided by the fuel cell power plant, or a voltage decay rate.

Abstract: A system and method for determining a loss of cooling fluid from a thermal sub-system in a fuel cell system. The method includes monitoring current feedback from a high temperature pump that pumps the cooling fluid through a coolant loop. A measured current from the pump is compared to an expected current for the system operating conditions, and if that current is significantly less than what is expected, then it may be as a result of low cooling fluid. If the measured current is less than the expected current for a predetermined period of time, then the system can take mitigating action as a result of a low cooling fluid. Further, if the pump speed is too low to provide an accurate current measurement, then it can be increased if an overflow tank level sensor indicates a low cooling fluid level.

Abstract: Methods and systems for electrical determination and adjustment of the fuel concentration in direct methanol fuel cells (DMFC) are provided.

Abstract: A direct oxidation fuel cell system including: a fuel cell which generates power from fuel and oxidant gas; a positive displacement pump for supplying the oxidant gas; a power supply for applying drive voltage to the pump; an oxidant gas flow conditioning unit for inhibiting pulsation of discharge pressure of the pump; a pressure sensor for detecting the discharge pressure; a load current sensor for detecting load current of the cell; a voltage sensor for detecting the drive voltage; a first memory for storing first information on a target supply flow rate of the oxidant gas, set based on the load current; a second memory for storing second information on relation of the drive voltage, discharge pressure, and target supply flow rate; and a controller for controlling flow rate of the oxidant gas, by using the informations, and values from the pressure, load current, and voltage sensors.

Abstract: Provided is a fuel cell system that can suitably control a voltage converter in response to a judgment that an abnormal condition occurs in a power detection unit that detects a power passing through the voltage converter. The fuel cell system has: a first power detection unit that estimates an effective value of a converter input power by multiplying the converter input power, which is obtained from a battery voltage and a battery current, by a converter efficiency; a second power detection unit that estimates a converter output power from a fuel cell voltage, a fuel cell current and a driving motor load power; and a third power detection unit that estimates a converter flowing power from a current of a reactor measured by a current sensor (shown in a separate drawing). The fuel cell system also has similar detection units for current, and using one of the detection units or a combination of some of them, specifies a malfunctioning sensor and prohibits correction of parameters.

Abstract: There is disclosed a fuel cell system including a fuel cell, a fuel supply system to supply a fuel gas to the fuel cell, an injector which adjusts a gas state on an upstream side of the fuel supply system to supply the gas to a downstream side, and a control unit which drives and controls the injector in a predetermined drive cycle. The control unit sets the drive cycle of the injector in accordance with an operation state of the fuel cell.

Abstract: The present invention includes a power generation section (8); an internal load (4, 6, 9, 10); an inverter (7); a voltage detector (12) and a current detector (11, 21); and a controller (6). The controller is configured to estimate a value of a current supplied to the internal load based on at least one of the current value detected by the current detector and an operation amount of the internal load, and control the inverter and the internal load based on the current value detected by the current detector and the estimated current value so that the electric power generated in the power generation section reaches the target electric power.

Abstract: There is disclosed a fuel cell system capable of stably operating auxiliary devices driven at a high voltage and the like, even in a case where a poisoned electrode catalyst is recovered or a fuel cell is warmed up. On detecting that the electrode catalyst is poisoned, a controller derives a target operation point which is sufficient for recovering an activity of the poisoned electrode catalyst. Then, shift of the operation point from a usual operation point to a low-efficiency operation point is realized so that an output power is held to be constant.

Abstract: In a method for regulating a fuel cell stack (1), a current-voltage characteristic of the fuel cell stack is detected and evaluated to determine an operating point of the fuel cell stack, wherein a current-voltage characteristic of the fuel cell stack (1) is detected at time intervals in operation whose gradient has a minimum, a characteristic value (Rmin) for the minimum of the gradient is respectively determined from the detected current-voltage characteristic and a desired value for the operating point is determined by addition of a predefined offset value (Roffset) to the characteristic value, and wherein the fuel cell stack (1) is regulated by the desired value determined in this manner.

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: The subject of the present invention relates to a method and a protector for reducing degradation of fuel cell systems at transitions in operation, in particular at electrodes or catalysts in a combustion chamber of a stack of a PEM fuel cell system in startup and shutoff events of the fuel cell system. A switchable material delivery device is provided for varying a delivery of material to the fuel cell system, so that a transition from a first state of the fuel cell system to a second state of the fuel cell system can be initiated, such that a potential difference between different electrodes can be effected. At least one reducing mechanism is provided for reducing the potential difference between the different electrodes during the transition, in which the reducing mechanism includes at least one compensating device for an unequal gas distribution by reducing the proportions causing degradation, to reduce degradation.

Abstract: A fuel cell system that includes a control system for regulating the power produced by the fuel cell system. The fuel cell system includes a fuel cell stack adapted to produce electrical power from a feed. In some embodiments, the fuel cell system includes a fuel processing assembly adapted to produce the feed for the fuel cell stack from one or more feedstocks. The control system regulates the power produced by the fuel cell system to prevent damage to, and/or failure of, the system.

Abstract: A system and method for breaking-in and humidifying membrane-electrode-assemblies (MEAs) in a fuel cell stack. The method includes performing voltage cycling and humidification of the MEAs in the stack, including one or more temperature steps wherein current density of the stack is cycled within a predetermined range for each of the one or more temperature steps. The method also includes maintaining a fuel cell stack voltage within a predetermined range, and maintaining anode and cathode reactant flows at an approximate set-point during the current density cycling of the one or more temperature steps to break-in and humidify the MEAs in the stack so that the stack is able to operate at a predetermined threshold for a fuel cell stack voltage output capability.

Abstract: A method for preventing a fuel cell voltage potential reversal including determining a relationship between the cell resistance and the current of a fuel cell stack at which a fuel cell voltage potential reversal will occur, operating the fuel cell stack according to a power demand requested, and determining the maximum cell resistance of the fuel cells in the stack. If the maximum cell resistance exceeds a threshold value for the current at which the fuel cell stack is being operated, the operation of the fuel cell stack is restricted to prevent the fuel cell voltage potential from reversing.

Abstract: A system and method for detecting small hydrogen leaks in an anode of a fuel cell system. The method includes determining that a shut-down sequence has begun, and if so, deplete the cathode side of a fuel cell stack of oxygen. The method then increases the pressure of the anode side of the fuel cell stack to a predetermined set-point, and monitors the pressure decay of the anode side of the stack. The method compares the rate of pressure decay to an expected pressure decay rate, and if the measured pressure decay rate exceeds the expected pressure decay rate by a certain threshold, determines that a potential leak exists.

Abstract: An output characteristic of a fuel cell is estimated by detecting an output current of the fuel cell and a voltage between terminals of the fuel cell, and then estimating the output characteristic of the fuel cell on the basis of the detected output current and the detected voltage between the terminals, and a basic output characteristic of the fuel cell.

Abstract: The present invention provides a method for controlling the operation of a fuel cell system at low temperature that can suitably prevent flooding in a cathode of a fuel cell stack during low-temperature operation, thus improving the operation stability and durability of the fuel cell stack.

Abstract: Systems and methods for sintering and conditioning fuel cell stacks utilizing channel guides, baffles, and internal compression systems are provided. Sintering and conditioning may be performed utilizing a fuel cell column cartridge assembly and fuel cell stacks may be sintered and conditioned at the system level during the same annealing cycle on the same support.

Abstract: 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.

Abstract: A fuel cell system includes a fuel cell; a voltage measuring portion that measures a voltage of the fuel cell; an electric current adjusting portion that adjusts an electric current flowing in the fuel cell; an electric current-voltage characteristic information obtaining portion that controls the electric current adjusting portion to change the electric current, and obtains electric current-voltage characteristic information that is information indicating a correspondence relation between an electric current value and a voltage value measured by the voltage measuring portion; and a negative voltage cause determining portion that determines, if the voltage of the fuel cell is a negative voltage, a cause of the negative voltage of the fuel cell, based on the obtained electric current-voltage characteristic information.

Abstract: A fuel cell system and a method for controlling the fuel cell system are provided. The method includes detecting an output characteristic value of the fuel cell system and controlling the fuel cell system to respectively operate in at least two of a first mode, a second mode and a third mode at different time points according to the detected output characteristic value. Accordingly, the fuel cell system is capable of stably generating electric power, and is adapted to different operation environments.

Abstract: The present invention provides a method for controlling output of a fuel cell to improve fuel efficiency of a fuel cell hybrid vehicle, in which the fuel cell is operated at a constant power at a maximum efficiency point, wherein the fuel cell and a storage means are directly connected if the output and energy of the storage means is insufficient, and the power generation of the fuel cell is stopped when the level of energy of the storage means is increased during stopping or during low power operation such that the fuel cell is intensively operated at the maximum efficiency point, thus improving the fuel efficiency of the fuel cell and the efficiency of the fuel cell system.

Abstract: A fuel cell power supply includes a fuel cell voltage detection means which detects a terminal-to-terminal voltage of the fuel cell; an internal resistance calculation element configured to supply electric power from a battery to a motor via a second DC-DC converter and configured to calculates a resistance value of an internal resistance of the fuel cell on the basis of a detection voltage of the fuel cell in a state where a current output of the fuel cell is stopped, a detection voltage of a terminal-to-terminal voltage of the fuel cell in a state where the output current of the fuel cell is adjusted to a value, and the value; and a deterioration level determination element configured to determines a deterioration level of the fuel cell on the basis of a change in the resistance value of the internal resistance of the fuel cell.

Abstract: Disclosed herein is a system for measuring performance of a solid oxide fuel cell, including: a heating furnace wrapping the solid oxide fuel cell, the heating furnace having a first opening part through which one lateral surface in a length direction of the solid oxide fuel cell outwardly protrudes and a fuel supply hole formed in one surface thereof; a first fuel storage unit; a second fuel storage unit; a first fuel supply control unit; a second fuel supply control unit; an electronic load measuring current or voltage outputted from the solid oxide fuel cell; and a control unit controlling the supply of fuel by using the first fuel supply control unit and the second fuel supply control unit, and controlling the measurement of current or voltage by using the electronic load.

Abstract: Disclosed is a system and method for controlling pressure oscillation in an anode of a fuel cell stack. In particular, an electronic control unit is configured to determine operation information including a reference power mapped based on the operating pressure of a fuel cell system and a reference differential pressure between at least two predetermined points in a vicinity of the anode, compare the power of the fuel cell system with the reference power and, when the power is less than the reference power, control the pressure in the anode to be an oscillating target pressure, and compare the measured differential pressure between the at least two points with the reference differential pressure and, when the measured differential pressure is less than the reference differential pressure, reduce a purge valve operation cycle.

Abstract: A limit switch for detecting opening/closing of a hood is connected to a controller. A power supply relay is also connected to the controller. A switching contact of the relay is located on power supply line for supplying power supply from a fuel cell. When the hood is closed, the limit switch is on and the controller maintains the switching contact in a closed state so that power supply from the fuel cell to various power-consuming components is allowed. On the other hand, when the hood is opened, the limit switch is turned off. In response to this, the controller opens the switching contact so that the power supply from the fuel cell to the various power-consuming components is shut off.

Abstract: A fuel cell system is provided which estimates a water content in a fuel cell based on a predetermined map using an integrated value of electric current generated by the fuel cell (ST4) before power generation is stopped (ST5). When a temperature of the fuel cell has fallen lower than a predetermined value (ST7) after the power generation is stopped (ST5), the fuel cell system determines a dry degree in the fuel cell (ST8) and an anode scavenging period (ST9) based on predetermined maps. Scavenging is performed in an anode in the fuel cell for the anode scavenging period (ST10).

Abstract: A method for determining the health of fuel cells in a fuel cell stack. The method includes maintaining a constant flow of hydrogen to the anode side of the fuel cell stack, shutting off a flow of air to a cathode side of the fuel cell stack when a predetermined concentration of hydrogen in the anode side has been achieved, and identifying a catalyst surface area and a catalyst support surface area for catalyst layers in the fuel cell stack. The method also includes determining the total parasitic current of the fuel cell stack to determine a cross-over parasitic current and a shorting resistance of the fuel cell stack. The method further includes calculating the catalyst surface area and the catalyst support surface area of the catalyst layers and comparing the difference between the identified catalyst surface area and the calculated catalyst surface area to estimate the change in the catalyst surface area.

Abstract: A telecommunication central office site monitor system comprising a central monitoring board configured to receive and send reported current values. The reported current values may be provided by current monitors, with each current monitor being arranged in-line with a power protection device and identified with a particular piece of telecommunication equipment.

Abstract: A contactor electrically connects and disconnects a fuel cell from a load. When a failure-detecting mode for detecting a closing failure of a contactor is initiated, an opening command is transmitted to the contactor, and a DC/DC converter connected to a motor changes the load voltage. Then, the load voltage and a fuel cell voltage are compared with each other. If the contactor is in a normal open state, as a result of the opening command, the fuel cell voltage is constant, whereas the load voltage of the DC/DC converter decreases, thereby producing a voltage difference. A closing failure of the contactor is determined when it is detected that the fuel cell voltage is substantially equal to the load voltage.

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: An operation method at the time of load increase of fuel cell system includes in this order a first step of determining a target power generation amount of the fuel cell module, a second step of increasing the flow rate of the oxygen-containing gas supplied to the fuel cell module, a third step of increasing the flow rate of the water supplied to the fuel cell module, a fourth step of increasing the flow rate of the fuel gas supplied to the fuel cell module, a fifth step of increasing the power generation amount of the fuel cell module, and a sixth step of detecting whether the power generation amount of the fuel cell module reaches the target power generation amount or more.

Abstract: A method for operating a fuel cell system includes electrically coupling the fuel cell stack to an energy storage device and an electrical demand by a load device at a substantially constant voltage. A controller controls an amount of an oxidant supply to the fuel cell stack based on the demand by the load device.

Abstract: A fuel cell is disclosed which is formed on a semiconductor wafer by etching channel in the wafer and forming electronics on the substrate electronically coupled to the fuel cell that controls generation of power by the fuel cell through electrical communication with the fuel cell. A hydrogen fuel is admitted into one of the divided channels and an oxidant into the other. The hydrogen reacts with a catalyst formed on an anode electrode at the hydrogen side of the channel to release hydrogen ions (protons) which are absorbed into the PEM. The protons migrate through the PEM and recombine with return hydrogen electrons on a cathode electrode on the oxygen side of the PEM and the oxygen to form water.

Abstract: One object is to provide a measuring device configured to evaluate the power generation characteristics of a response-delay type fuel cell automatically, precisely, and with excellent reproducibility with consideration of the response delay against power load fluctuations, and effectively acclimatize and develop microorganisms that are provided to generate power. A potentio-galvanostat is connected to a microbial fuel cell provided as an exemplary response-delay type fuel cell. Further, an automatic measuring device is connected to the potentio-galvanostat. The automatic measuring device has a program function and measures the internal resistance of the microbial fuel cell at set time.

Abstract: A fuel cell system includes an accumulated current value measuring unit. The accumulated current value measuring unit measures an accumulated current value by time integration of current output from the fuel cell in a period during which oxygen is produced by water-splitting reaction in an anode of a negative voltage cell. A control unit uses a first correlation between the accumulated current value in the oxygen generation period and an oxygen consumption rate in the anode and a second correlation between a current density of the fuel cell in the oxygen generation period and an oxygen production rate in the anode to obtain a current density at or below which the amount of oxygen in the anode may be reduced, and causes the fuel cell to output electric power at a current density lower than the obtained current density.

Abstract: A fuel cell system includes a fuel cell; a cathode inflow water amount determining portion that determines a cathode inflow water amount after activation of the fuel cell; an obtaining portion that obtains a pore total volume of the cathode side catalyst layer; an operating condition determining portion that determines, based on the determined cathode inflow water amount and the obtained pore total volume, an operating condition of the fuel cell that includes a current value of current that flows through the fuel cell and an upper limit value of a period of time for which the current flows, for bringing the cathode inflow water amount within a range that is equal to or less than the pore total volume; and an adjusting portion that adjusts the current value and the period of time for which current of the current value flows, such that the determined operating condition is realized.

Abstract: An energy adjusting method for controlling output energy of a fuel cell group, wherein at least one of the fuel cell group and a secondary battery group drives a load is disclosed. The voltage of the fuel cell group is boosted by a boost regulation module to generate a first adjustment voltage. The boost regulation module boosts the voltage of the fuel cell group according to a first control signal. The first adjustment voltage is dropped by a drop regulation module to generate a second adjustment voltage to the load. The drop regulation module drops the first adjustment voltage according to a second control signal. At least one of the fuel cell group, the boost regulation module, the drop regulation module and the load is detected to generate a detection result. The first and the second control signals are generated according to the detection result.

Abstract: A fuel cell system includes: a fuel cell stack that is formed of a plurality of serially connected fuel-cell cells that use fuel gas and oxidant gas to generate electric power; a detecting unit that detects an output power generated by each of a first fuel-cell cell group and a second fuel-cell cell group that are grouped on the basis of a power generation performance factor; and an operating condition changing unit that changes an operating condition of the fuel-cell cells on the basis of a rate of deviation between the generated output power of the first fuel-cell cell group, detected by the detecting unit, and the generated output power of the second fuel-cell cell group, detected by the detecting unit.