Abstract: A fuel cell system acquires an operation state of a fuel cell and estimates an IV characteristic that indicates a relationship between a current and a voltage in the fuel cell. At least one of a resistance overvoltage, an activation overvoltage, a current-voltage hysteresis and a concentration overvoltage of the fuel cell is determined from the operation state of the fuel cell, and the IV characteristic is estimated based on the determined result.

Abstract: Embodiments of the present invention disclose a fuel cell control method. The method includes: obtaining a current output power of a fuel cell; obtaining a current inlet-outlet temperature difference of a fuel cell stack, where the current inlet-outlet temperature difference of the stack is a difference between a stack temperature and an ambient temperature; controlling a hydrogen exhaust solenoid valve according to the output power and working parameters of the hydrogen exhaust solenoid valve corresponding to the output power; and controlling the stack temperature according to the output power and the current inlet-outlet temperature difference of the stack, so that the amount of water generated in the fuel cell is equal to the amount of water discharged. In the embodiments, the fuel cell can work in a preferred state, steady output of the cell is ensured, and the service life is improved.

Abstract: Voltage rising detection unit detects a voltage rising condition of a fuel cell stack after the supply of reactant gas to the fuel cell stack is started. A control unit determines an internal state of the fuel cell stack on the basis of the detected voltage rising condition of the fuel cell stack, and then decides a subsequent operation of the fuel cell stack in accordance with the determination. This makes it possible to minimize deterioration of the fuel cell stack which is caused by generating power continuously in an unsuitable state.

Abstract: A fuel cell system includes a fuel cell and a supplying unit, which supplies reactive gases to the fuel cell. A control unit includes a power production effective area calculator calculates the areas of the electrodes available for power production as a power production effective area. A current density calculator which calculates a current density of the power production effective area calculated by the power production effective area calculator based on the total amount of power required by the fuel cell. A gas supply amount determiner determines the amount of reactive gas to be supplied to the fuel cell depending on the current density. A gas supply controller controls the supplying unit so as to supply the amount of reactive gas determined by the gas supply amount determiner to the fuel cell.

Abstract: An electric power generator is particularly suitable for providing back-up power to sites with multiple power requirements. This generator comprises a rack having multiple module bays; at least one power conversion module is mounted in one of the bays and is electrically coupled to a fuel cell stack also mounted in the rack or located remote from the rack. The power conversion module converts the voltage level and/or current type of some of the electricity produced by the stack such that the generator can simultaneously output electricity at multiple voltage levels and/or current types. The rack can be a standardized nineteen relay rack, making the generator relatively compact and compatible with sites configured accept such racks.

Abstract: An intermediate circuit for controlling the connection of a fuel cell stack to a load bus includes three switching elements arranged in a pi configuration. At least one such switching element is provided for short circuiting either or both of the fuel cell stack and the load bus, while a further switching element controllably interrupts the line connection between the fuel cell stack and the load bus. The respective switches are driven according to a control method that accommodates start-up operation, switch-off operation, emergency shut down, and a self diagnostic mode.

Abstract: When starting operation of a fuel cell below the freezing point, a fuel cell system adjusts the open degree of a hydrogen pressure adjusting valve, introduces hydrogen to a hydrogen entrance of the fuel cell so as to make the total pressure of the hydrogen entrance is a first pressure, and starts a hydrogen circulation pump. If at least one of the cell voltages acquired by a cell voltmeter is below a predetermined voltage, the system determines that clogging is caused in a hydrogen flow channel in the fuel cell. When it is determined that clogging is present, the open degree of the pressure adjusting valve is adjusted and hydrogen is introduced to the hydrogen entrance so that the total pressure of the hydrogen entrance is a second pressure which is higher than the first pressure. Then, the hydrogen circulation pump is stopped and the fuel cell is warmed up to dissolve the clogging of the hydrogen flow channel.

Abstract: A method for performing a plausibility check of a fuel cell stack anode side pressure sensor to determine whether the pressure sensor is providing an accurate measurement. Prior to system start-up when a cathode side compressor is not providing cathode air to a fuel cell stack, and the cathode side of the stack is at ambient pressure, a pressure measurement from a differential pressure sensor between the anode side and the cathode side of the fuel cell stack is provided. The differential pressure sensor reading is added to a pressure measurement from an ambient pressure sensor, where the sum should be about the same as the pressure measurement from the anode side pressure sensor if the anode side pressure sensor is operating properly.

Abstract: An algorithm for determining the maximum net power available from a fuel cell stack as the stack degrades over time using an online adaptive estimation of a polarization curve of the stack. The algorithm separates the current density range of the stack into sample regions, and selects a first sample region from the far left of the estimated polarization curve. The algorithm then calculates the cell voltage for that current density sample region, and determines whether the calculated cell voltage is less than or equal to a predetermined cell voltage limit. If the calculated cell voltage is not less than the cell voltage limit, then the algorithm selects the next sample region along the polarization curve. When the calculated cell voltage does reach the cell voltage limit, then the algorithm uses that current density for the sample region being analyzed to calculate the maximum power of the fuel cell stack.

Abstract: A fuel cell system of the invention includes, a fuel cell, a water reservoir configured to accumulate water discharged from the fuel cells, and a status estimator configured to estimate a status of the water reservoir based on a stated of the fuel cell.

Abstract: A technique is described herein for monitoring the operational state of a fuel cell stack by the detection of nonlinearity in such a manner that an external test signal for frequency response is generated and applied to the fuel cell stack during operation, the resulting signal output from the fuel cell stack is measured, and the harmonic content of the measured signal is analyzed, the method including: applying a multiple frequency test signal comprising at least two sinusoidal waves as the test signal for frequency response to the fuel cell stack; and analyzing the resulting current or voltage signal output from the fuel cell stack.

Abstract: A method for operating a direct methanol fuel cell is provided. The fuel cell includes a fuel cell main body having a fuel electrode and an air electrode disposed in opposing positions on either side of an electrolyte film. In this method, an aqueous methanol solution is supplied directly to the fuel electrode. A quantity of the aqueous methanol solution supplied is controlled in accordance with an electric current value drawn from the fuel cell main body so as to minimize a quantity of unused methanol within a discharge fluid discharged from the fuel electrode.

Abstract: The present invention provides an improved method for determining the amount of reactant gases supplied to a fuel cell system to ensure a stable supply of reactant gases to a fuel cell stack. In particularly, the present invention estimates an output current value of a fuel cell stack by detecting the state of charge of an electricity storage device connected in parallel to the fuel cell stack; measures a target current value according to the amount of output required by a driver; determines the amount of reactant gases to be supplied by comparing the estimated output current value and the target current value; and supplies the determined amount of reactant gases to the fuel cell stack.

Abstract: A method of operating a fuel cell system is disclosed, the method including the steps of providing a fuel cell stack including a plurality of fuel cell assemblies, each fuel cell assembly having a proton exchange membrane disposed between a plurality of fuel cell plates, wherein water is purged from the fuel cell system during a shutdown operation, and a current is produced in the fuel cell system following the shutdown purge to produce product water to hydrate the proton exchange membrane.

Abstract: A fuel cell power system includes a fuel cell stack prepared by stacking a plurality of electric cells, each having an anode and a cathode with an electrolyte therebetween, a fuel supply line and an oxidant supply line that respectively supply a fuel and an oxidant to the fuel cell stack, and a fuel exhaust line and an oxidant exhaust line that respectively exhaust the fuel and oxidant supplied to the fuel cell stack.

Abstract: A fuel cell system includes a fuel cell, a secondary battery, an oxidizing gas supplier, a gas supply flow regulator, an oxidizing gas supply path, a cathode off-gas exhaust path, a bypass flow path, a flow regulator, an available power output acquirer, and an operation controller, wherein the gas supply flow regulator regulates the gas supply flow rate to cause the oxidizing gas supplier to supply an excess gas flow rate, which is set to be greater than a target fuel gas-requiring gas flow rate, wherein the target fuel gas-requiring gas flow rate is the fuel cell-requiring gas flow rate to be supplied to the fuel cell in order to achieve the target current value, when the available power output is less than a minimum amount of electric power required for the oxidizing gas supplier to increase the gas supply flow rate from 0 to a preset gas flow rate within a preset time period, and the operation controller controls the flow regulator to make the bypass flow rate equal to a difference gas flow rate between th

Abstract: A fuel cell stack (10) is operated with a low air utilization which is very low when the stack is providing low current density, and is operated with air utilization increasing as a function of current density above a predetermined current density.

Abstract: A hybrid voltage supply apparatus, a method of controlling the same, and an electronic system employing the hybrid voltage supply apparatus as a power supply are provided. The hybrid voltage supply apparatus includes a hybrid voltage supply apparatus including a main power supply, an auxiliary power supply, and a first voltage adjustment unit which operates in any one of a feed-forward driving mode and a feed-back driving mode according to at least one operating parameter of the main power supply, and adjusts an output voltage of the main power supply to a first predetermined DC voltage.

Abstract: A system voltage indicated by an intersection of a graph of an FC maximum output characteristic of the output voltage/output power characteristic of a fuel cell and a graph of a load device maximum output characteristic is output so as to obtain optimal output power, thereby matching an output current-output voltage characteristic of a fuel cell and a maximum output characteristic of a load. Thus, a fuel cell system which has high operating efficiency and which is free of physical failures is provided.

Abstract: A technique includes operating an electrochemical cell as a pump, including providing a current to the cell and providing a fuel flow to an anode chamber of the cell. The technique includes communicating an anode exhaust flow from the anode chamber to an oxidizer and controlling the current to regulate a temperature of the oxidizer.

Abstract: There is provided a power generation system. A chemical reacting section receives a power generation fuel and reforms the power generation fuel to generate a power generation gas containing hydrogen. A power generating section receives the power generation gas, reacts a part of the power generation gas to generate electrical energy, supplies the electrical energy to a load, and discharges an unreacted component in the power generation gas as an off-gas. A heating section receives the off-gas and generates a thermal energy by using the off-gas to heat the chemical reacting section. An output control section controls the amount of electrical energy output from the power generating section. A control section controls the amount of electrical energy output from the power generating section to change a temperature of the chemical reacting section set based on the thermal energy to a predetermined temperature.

Abstract: One aspect of the present invention provides an electrochemical cell system comprising at least one electrochemical cell configured to be selectively connected to a load to discharge the cell by generating electrical current using a fuel and an oxidant. The electrochemical cell system may alternatively be connected to a power supply to recharge the cell. The electrochemical cell system comprises a plurality of electrodes and electrode bodies therein. The electrochemical cell system further comprises a switching system configured to permit progressive movement of the anodes used for charging each electrochemical cell, maintaining a minimum distance from a progressively moving cathode that is the site of fuel growth.

Abstract: A system and method for determining reactant gas flow through a fuel cell stack to determine potential stack problems, such as a possible low performing fuel cell. The method includes applying a perturbation frequency to the fuel cell stack and measuring the stack current and stack voltage in response thereto. The measured voltage and current are used to determine an impedance of the stack fuel cells, which can then be compared to a predetermined fuel cell impedance for normal stack operation. If an abnormal fuel cell impedance is detected, then the fuel cell system can take corrective action that will address the potential problem.

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: A motor system includes a drive motor configured to generate a drive force using power supplied from a fuel cell; an idle control unit configured to operate the fuel cell intermittently between an idle operation mode and an idle stop mode; a state detection unit configured to detect a state of the fuel cell when the idle stop mode of the fuel cell ends; a recovery time estimation unit configured to estimate a recovery time taken for total voltage of the fuel cell to reach voltage at the idle operation based on the state of the fuel cell detected by the state detection unit; and a control unit configured to perform a correction control for torque of the drive motor based on the recovery time estimated by the recovery time estimation unit.

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 fuel cell power plant (9) includes a stack (10) of fuel cells, each including anodes (11), cathodes (12), coolant channels (13) and either (a) a coolant accumulator (60) and a pump (61) or (b) a condenser and cooler fan. During shutdown, electricity generated in the fuel cell in response to boil-off hydrogen gas (18) powers a controller (20), an air pump (52), which may increase air utilization to prevent cell voltages over 0.85 during shutdown, and either (a) the coolant pump or (b) the cooler fan. Operation of the fuel cell keeps it warm; circulating the warm coolant prevents freezing of the coolant and plumbing. The effluent of the cathodes and/or anodes is provided to a catalytic burner (48) to consume all hydrogen before exhaust to ambient. An HVAC in a compartment of a vehicle may operate using electricity from the fuel cell during boil-off.

Abstract: A fuel cell system includes a first power generation module configured to have a power generation assembly including a catalyst, an anode-side non-power generation structure placed in contact with the power generation assembly, and a cathode-side non-power generation structure placed on opposite to the power generation assembly across the power generation assembly, at least one second power generation module placed adjacent to the first power generation module, and a current regulation circuit connected in parallel to each of the power generation modules.

Abstract: A method is provided for fuel cell system control. In this method, the operation of a fuel cell system is divided into several modes, and the operation mode of the fuel cell system can be decided according to voltage signals, current signals and temperature signals of the fuel cell system. Moreover, a fuel cell system using this control method is also provided.

Abstract: The level of electrical current produced by a fuel cell during rapid changes in the power demanded by a load, is clamped to the fuel cell's maximum rated current value in order to avoid damage to the fuel cell. When the current supplied to the load by the fuel cell overshoots the maximum rated current value, the fuel cell current is immediately reduced by increasing the fuel cell voltage.

Abstract: Provided is a fuel cell system that performs a warm-up operation by reducing a supply of oxidant gas to a fuel cell, the system having: a fuel cell; and a control unit that regulates amounts of oxidant gas and fuel gas supplied to the fuel cell and controls a power-generation state of the fuel cell. During the warm-up operation with a reduced supply of oxidant gas to the fuel cell, the control unit varies a voltage of the fuel cell for a short period of time to obtain current-voltage characteristics which indicate a relationship of an output voltage and an output current of the fuel cell, calculates an effective catalyst area of the fuel cell based on the obtained current-voltage characteristics, and determines whether the warm-up operation of the fuel cell can be stopped or not based on the calculated effective catalyst area.

Abstract: A management ECU of a control unit predicts the reduction degree of a system voltage according to an operational state of a motor based on the temperature of a fuel cell and a number of rotations of the motor, sets motor output restriction start voltage and motor output restriction end voltage which are threshold values of the system voltage for triggering an execution start and an execution end of a processing to restrict an output of the motor, and outputs them to a motor ECU. The motor ECU sets an output restriction coefficient that is a restriction rate in restricting the output of the motor based on a detected value of the system voltage and the motor output restriction start voltage and the motor output restriction end voltage, and restricts the output of the motor.

Abstract: A fuel cell system includes a fuel cell, a fuel supply portion that supplies fuel to the fuel cell, a combustion portion that burns an anode exhaust gas discharged from the anode of the fuel cell, and an oxygen concentration detection portion that detects the oxygen concentration in a predetermined gas. The fuel flow control portion controls the amount of flow of fuel supplied from the fuel supply portion to the fuel cell so that the amount of fluctuation of the oxygen concentration in the combustion exhaust gas discharged from the combustion portion which is detected by the oxygen concentration detection portion is between a first value and a second value that is larger than the first value.

Abstract: Disclosed is a fuel cell system capable of stabilizing the power generation state of a fuel cell for a period of transition from a power generation stop state during an intermittent operation or the like to a usual operation. The fuel cell system supplies a fuel gas from a fuel supply source to a fuel cell to generate a power, and comprises output limit means for limiting the output of the fuel cell after shift from the power generation stop state of the fuel cell to a power generation state.

Abstract: Provided is a fuel cell system that performs a warm-up operation by reducing a supply of oxidant gas to a fuel cell, the system having: a fuel cell; and a control unit that regulates amounts of oxidant gas and fuel gas supplied to the fuel cell and controls a power-generation state of the fuel cell. During the warm-up operation with a reduced supply of oxidant gas to the fuel cell, the control unit varies a voltage of the fuel cell for a short period of time to obtain current-voltage characteristics which indicate a relationship of an output voltage and an output current of the fuel cell, calculates an effective catalyst area of the fuel cell based on the obtained current-voltage characteristics, and determines whether the warm-up operation of the fuel cell can be stopped or not based on the calculated effective catalyst area.

Abstract: A system and method for correcting a large fuel cell voltage spread for a split sub-stack fuel cell system. The system includes a hydrogen source that provides hydrogen to each split sub-stack and bleed valves for bleeding the anode side of the sub-stacks. The system also includes a voltage measuring device for measuring the voltage of each cell in the split sub-stacks. The system provides two levels for correcting a large stack voltage spread problem. The first level includes sending fresh hydrogen to the weak sub-stack well before a normal reactive bleed would occur, and the second level includes sending fresh hydrogen to the weak sub-stack and opening the bleed valve of the other sub-stack when the cell voltage spread is close to stack failure.

Abstract: A system and method for detecting and predicting low performing cells in a fuel cell stack. When the fuel cell stack is running and certain data validity criteria have been met, an algorithm collects the data, such as stack current density, average cell voltage and minimum cell voltage. This information is used to estimate predetermined parameters that define the stack polarization curve. The system defines a predetermined minimum current density that is used to identify a low performing cell. The system then calculates an average cell voltage and a minimum cell voltage at the minimum current density set-point, and calculates a cell voltage difference between the two. If the cell voltage difference is greater than a predetermined low voltage threshold and the minimum cell voltage is less than a predetermined high voltage threshold, the algorithm sets a flag identifying a potential for a low performing cell.

Abstract: According to the invention, a hybrid fuel cell system (100) is characterized by comprising a load portion (3) which consumes electric power; first control means (11) for obtaining a supply electric power set value (P bat ref) indicating electric power supplied from the electric power storage device (40), based on a supply electric power set value (P fc ref) indicating electric power supplied from the fuel cell (20) and a consumption electric power set value (P mot ref) indicating electric power consumed by the load portion (3); difference obtaining means (41) for obtaining a difference between the supply electric power set value (P bat ref) and an actual supply electric power value (P bat mos) indicating electric power actually supplied from the electric power storage device (40); and second control means (12) for controlling the amount of electric power consumed by the load portion (3) based on the difference.

Abstract: The fuel cell system is provided with a fuel cell, a fuel supply system for supplying fuel gas to the fuel cell, an injector for regulating the gas state upstream in the fuel supply system and supplying the gas downstream, and control means for driving and controlling the injector at a predetermined drive cycle. The control means sets the working state of the injector in response to the operating state of the fuel cell.

Abstract: Disclosed is a fuel cell including a fuel cell stack; a stack case which contains the fuel cell stack; and a blocking device including connecting portions which electrically connect, to output terminal portions of the fuel cell stack, output cables to transmit the output of the fuel cell stack to a device provided outside the stack case, the blocking device being capable of blocking the mutual connection performed by the mechanical operation of the connecting portions from the outside of the stack case. Moreover, at least a portion of the blocking device in which the output cables are electrically connected to the connecting portions is arranged outside the stack case.

Abstract: A method of operating a fuel cell includes the step of selectively connecting and disconnecting the fuel cell to at least one electrical load dependent at least in part upon at least one of a fuel cell voltage, a fuel cell current and a fuel cell temperature.

Abstract: A control device for a vehicular fuel cell system is provided with a warm-up output control section operative, when a fuel cell system is started up under a low temperature condition and in case that a fuel cell stack of the fuel cell system is warmed up, causing the fuel cell stack to generate electric power to allow predetermined warm-up electric power to be taken out, and a run permission section operative, during a period wherein the warm-up electric power is drawn by the warm-up output control section, to determine whether the fuel cell stack assumes a predetermined warm-up condition on the basis of one of a voltage value and an electric current value of the fuel cell stack. When a determination is made that the fuel cell stack assumes the predetermined warm-up condition, the run permission section provides a vehicle with run permission.

Abstract: A method of operating a fuel cell includes: generating an electrical power in a fuel cell stack while no fuel is being supplied from a fuel tank; reducing an output voltage of the electrical power toward a target voltage to increase an output current of the electrical power; measuring a rate of increase of the output current; starting supply of fuel to the fuel cell stack when the rate of increase of the output current is below a threshold rate; and controlling a fuel concentration in the fuel cell stack to maintain the output current at a target current level.

Abstract: A fuel cell system is disclosed with a fuel cell stack having a plurality of fuel cells, the fuel cell stack including an anode supply manifold and an anode exhaust manifold, a sensor for measuring at least one of an environmental condition affecting the fuel cell stack and a characteristic of the fuel cell stack, wherein the sensor generates a sensor signal representing the measurement of the sensor; and a processor for receiving the sensor signal, analyzing the sensor signal, and controlling a flow rate of a fluid flowing into the anode supply manifold based upon the analysis of the sensor signal.

Abstract: A system and method for converting a fuel cell stack power request signal to a stack current set-point that considers stack performance parameters. The method includes obtaining a power-current relationship curve of the fuel cell stack to provide stack parameters including exchange current density and mass transfer coefficient. The method then calculates a slope for the stack using the parameters from the power-current relationship curve estimation that includes calculating a cell voltage at two predetermined stack current densities. The method then calculates a change in current in response to the power request signal, the stack voltage, the stack current and the calculated slope, and uses the change in current to update the current set-point for the stack.

Abstract: The invention relates to fuel cell non-humidification operation, specifically to—a method on dry operation condition selection, wherein under condition of inputting dry gas, applying predetermined temperature, pressure and the input flow of the dry gas and detecting the temporary current-voltage curve of the cell. The selection method of this invention can realize steady operation of the cell under non-humidification condition and avoid the dehydration problem of the membrane under the dry gas as well as the “flood” phenomena. The present invention can be applied to not only normal temperature work condition, but also the start and run of the fuel cell under zero degree temperature condition especially. It can simplify the system of the fuel cell and therefore improve the development of the fuel cell.

Abstract: A fuel cell measurement apparatus capable of measuring electric characteristics of a solid oxide fuel cell is provided. The fuel cell measurement apparatus comprises a first current collecting unit, a second current collecting unit, a top holding set, a bottom holding set and an adjustable elastic load set. The solid oxide fuel cell is clipped by the first current collecting unit fixed by the top holding set and the second collection unit fixed by the bottom holding set. The adjustable elastic load set is capable of adjusting the tension between the top holding set and the bottom holding set. The first (second) current collecting unit comprises a first (second) conductive mesh and a first (second) porous plate having a first (second) through hole and a first (second) gas channel communicating with each other, wherein the first (second) conductive mesh is sintered on the first (second) porous plate.

Abstract: A method of controlling a fuel generating reaction of a fuel cell includes: a. providing a first reactant; b. activating the first reactant to generate fuel to the fuel cell; c. when a characteristic value of the fuel cell reaches a first reference value during the activation, adding a quantity of a second reactant to the first reactant to determine a monitoring time; d. after the monitoring time, detecting the characteristic value of the fuel cell to acquire a first characteristic value; e. if the first characteristic value is lower than the first reference value, performing step d.; f. if the first characteristic value is higher than the first reference value, detecting the characteristic value of the fuel cell to acquire a second characteristic value after a delay time; and g. if the second characteristic value is lower than the first reference value, proceeding to step d.

Abstract: At a start of a fuel cell, discharge of a generated water is ended at a proper timing. Supply of the reactive gas is started at a first flowrate. Then, in a case that the generated water retained by a reactive electrode is determined to outflow to an internal gas flow channel side among unit cells more than or equal to a preset determination cell number, the flowrate of the reactive gas is changed to a second flowrate that is smaller than the first flowrate.

Abstract: A method for controlling a fuel cell system is provided. In this method, the operation of a fuel cell system is divided into several modes, and the operation mode of the fuel cell system is determined according to voltage signals, current signals, and temperature signals of the fuel cell system. Moreover, a fuel cell system using the control method is also provided.