A fuel cell system comprising: a power generation controller that controls a value subject to control, which is a value exhibiting a power generating state by a fuel cell and is a value that is affected by alternating current applied to the fuel cell, to approach a target value; a dead zone setter that sets a dead zone with the target value as a reference; and, a stopper that stops the control by the power generation controller when the value subject to control is contained in the dead zone.

A control method for fuel cell system capable of executing an idle stop operation is provided, in which operation power generation of a fuel cell is selectively stopped according to a required output of a load and cathode gas is intermittently supplied to the fuel cell during an operation stop. An upper limit value and a lower limit value of an output voltage of the fuel cell during the idle stop operation is set, the cathode gas is intermittently supplied with the output voltage of the fuel cell set at a value between the upper limit value and the lower limit value, a wet/dry state of the fuel cell is detected, a wet/dry appropriate range in which the wet/dry state of the fuel cell during the idle stop operation is appropriate is set, and it is determined whether or not the detected wet/dry state of the fuel cell is within the set wet/dry appropriate range. If the wet/dry state of the fuel cell is determined to be outside the set wet/dry appropriate range, the output voltage of the fuel cell is reset, and the cathode gas is intermittently supplied with the output voltage of the fuel cell set at a value between the upper limit value and lower limit value of the reset output voltage.

Provided is a power control apparatus for a fuel cell vehicle which includes a fuel cell and which is driven by an electric motor that is supplied with electric power from the fuel cell. The power control apparatus includes an accelerator sensor that detects an operation of an accelerator, and a control unit that controls the fuel cell to increase the output power of the fuel cell so as to correspond to an increase in a requested acceleration output based on the detected accelerator opening degree. When the accelerator opening degree is less than a first accelerator determination value that is set in advance, the control unit controls the fuel cell to suppress an increase in the output power thereof.

A method of operating a vehicle includes, using a master power control module, and in response to a propulsion demand global to the vehicle, operating a master-assigned motor to which a wheeled drivetrain is mechanically connected to satisfy a share of the propulsion demand. The method additionally includes, using a slave power control module, and in response to the propulsion demand, operating a slave-assigned motor to which the drivetrain is mechanically connected to satisfy a remaining share of the propulsion demand.

A method of operating a redox flow battery string including at least first and second redox flow batteries and an outside power source includes: providing a least first and second redox flow batteries in a string electrically connected in a string, and each redox flow battery having a state-or-charge (SOC) and an electrical load, wherein the electrical load for at least one of the first and second redox flow batteries in the string is powered by the outside power source; obtaining an SOC value for each redox flow battery in the string; identifying a target SOC value in the string; and adjusting the SOC value for at least one of the first and second redox flow batteries to correspond to the target SOC value by using a portion of stored energy in the at least one first or second redox flow battery to supply power to the electrical load.

A fuel cell system is equipped with a fuel cell and a secondary battery. This fuel cell system is equipped with a recordation unit that records a charge-discharge history of the secondary battery, a prediction unit that predicts restriction on an output of the secondary battery based on the charge-discharge history recorded by the recordation unit, and an output control unit that starts power generation by the fuel cell prior to a timing of restriction on the output of the secondary battery, when the prediction unit predicts restriction on the output of the secondary battery and the fuel cell is in an intermittent operation state.

A fuel cell assembly according to an exemplary aspect of the present disclosure includes, among other things, a first fuel cell stack in series with a variable resistor and a second fuel cell stack in parallel with the first fuel cell stack and in series with a contactor. A resistance level of the variable resistor is adjusted in response to deactivating the contactor. A method of regulating a fuel cell assembly is also disclosed.

A drive circuit comprising a DC bus configured to supply power to a load, a first fuel cell coupled to the DC bus and configured to provide a first power output to the DC bus, and a second fuel cell coupled to the DC bus and configured to provide a second power output to the DC bus supplemental to the first fuel cell. The drive circuit further includes an energy storage device coupled to the DC bus and configured to receive energy from the DC bus when a combined output of the first and second fuel cells is greater than a power demand from a load, and provide energy to the DC bus when the combined output of the first and second fuel cells is less than the power demand from the load.

A method for controlling an operating point change of a fuel cell stack (10) operated with an anode operating medium and with a cathode operating medium, in which the fuel cell stack (10) is controlled in such a way that, starting from an initial electric power (L1), the fuel cell stack generates a target power (L2) requested by an electrical consumer (51), which is greater than the initial power (L1) is provided. It is provided that the electric power generated by the fuel cell stack (10) is controlled in accordance with a predetermined current-voltage profile (S1, S2, S3), so that a voltage present at the fuel cell stack (10), starting from an initial voltage (U1) corresponding to the initial power (L1), passes through a local voltage minimum (U.sub.min) and then increases to an end voltage corresponding to the target power (L2).

A method for changing a fuel cell system from a normal mode of operation over to a standby mode comprises the following steps: a) reducing the load withdrawalvia the electric circuit of the fuel cell stackdown to a load within the range from 1% to +5% around a load with an optimal system efficiency, b) regulating down the anode pressure down via the anode supply system, c) in the meantime, maintaining and controlling the cathode gas feed via the cathode supply system so that the pressure differential between the anode spaces and the cathode spaces does not exceed a prescribed maximum pressure differential, d) switching off the cathode gas feed if the pressure differential between the anode spaces and of the fuel cell stack and the environment has reached the prescribed maximum pressure differential, and e) switching off the load withdrawal via the external electric circuit at the latest when a prescribed minimum limit voltage of the fuel cell stack has been reached.