An air pressure in fuel cells of an electric power generation system comprising a fuel cell stack (PCS) is raised with a pressurized air cooling system with recirculation to values at least two times greater than typical values for an PCS with air cooling. The FCS is either placed in a high-pressure chamber to which air is injected, or air outgoing from the FCS is redirected via a duct back to the FCS inlet and a portion of pressurized fresh air is added thereto. The chamber or the duct is provided with a radiator by means of which circulating air heat is transferred into the external environment. Air recirculation in the chamber or the duct is effected by means of fans for cooling fuel cells. Useful capacity of electric power generation systems based on fuel cells is raised significantly, the necessity of using a humidifier is excluded, and the temperature range of fuel cell operation is expanded.

Various embodiments may provide non-isolated single-input dual-output (SIDO) bi-directional buck-boost direct current (DC) to DC (DC-DC) converters. Various embodiments may provide a method for controlling a buck duty cycle of the non-isolated SIDO bi-directional buck-boost DC-DC converter such that a first voltage measured across a first portion of the non-isolated SIDO bi-directional buck-boost DC-DC converter is maintained at less than a voltage of a first load and a second voltage measured across a second portion of the non-isolated SIDO bi-directional buck-boost DC-DC converter is maintained at less than a voltage of a second load.

A torque generating system is described, and includes a fuel cell power device, a high-voltage battery, an electric drive unit, and a controller. The fuel cell power device has a non-linear power-temperature relationship that has a local temperature maxima at a first electric power level and a local temperature minima at a second electric power level. A first operating point of the fuel cell power device is less than the first electric power level, and a second operating point of the fuel cell power device is set at a third electric power level that is greater than the first electric power level, wherein the third electric power level generates a fuel cell temperature that is less than the local temperature maxima. The fuel cell power device is controlled to one of the first operating point or the second operating point to transfer electric power to the electric drive unit.

A battery-powered motor may include an electric motor, a controller, and a housing. The electric motor may be wound to enable the battery-powered motor to achieve a non-limited motor maximum motor revolutions per minute (RPM) for at least one specified battery. The controlling current may include limiting current to the electric motor at lower RPMs, and limiting the current to prevent the RPM of the electric motor from exceeding a limited maximum motor RPM which is lower than the non-limited motor maximum RPM. The housing may enclose the electric motor and the controller and the specified battery. The housing may have a form factor to engage with a machine that engages with an internal combustion engine that has a maximum engine RPM that is approximately the same as the limited maximum motor RPM.

The disclosure relates to a fuel cell system comprising a fuel cell stack for providing an electrical power P.sub.stack depending on a power demand, at least one auxiliary unit for operating the fuel cell stack with an electrical power consumption P.sub.aux, at least one consumer with an electrical power request P.sub.use, and a control unit for regulating the power demand as well as a method for controlling such a fuel cell system. It is provided that the control unit is configured to selectively operate the fuel cell system in a first operating mode or in a second operating mode, whereby the fuel cell stack is turned off depending on the operating mode upon the falling below of an optimal efficiency degree operating point P(η.sub.max) of the fuel cell system or a minimum operating point P.sub.min of the fuel cell stack. In particular, at least one auxiliary unit is also turned off in the first operating mode, when the optimal efficiency degree operating point decreases.

A fuel cell system has a first boost converter of a fuel cell, a second boost converter of a secondary battery, and a control unit. Output sides of the first boost converter and the second boost converter are connected so as to be the same potential. The control unit is configured to, when detecting failure of the second boost converter, cause input and output sides of the second boost converter to conduct, estimate an open circuit voltage of the secondary battery based on a state of charge, and execute electric power consumption by an accessory that operates by electric power supplied from the fuel cell when determining that the first boost converter is not able to boost the output voltage of the fuel cell to the open circuit voltage, and stops the electric power consumption by the accessory when determining that the first boost converter is able to boost.

One aspect of the present disclosure is directed to a fuel cell power system. The system may include one or more fuel cells configured to generate electric power and a compressor configured to supply compressed air to the one or more fuel cells. The system may further include one or more sensors. The sensors may be configured to generate a signal indicative of at least one measured parameter of air flow across the one or more fuel cells. The system may also include a controller in communication with the one or more fuel cells, the compressor, and the sensors. The controller may be configured to determine a desired pressure drop based on at least one calculated parameter, determine a control command for the compressor based on the desired pressure drop, and adjust the control command based on a feedback gain parameter and a feed forward gain parameter.

A fuel cell system (200), wherein the fuel cell system (200) has: a) a fuel cell stack (10), b) an anode gas path (20) which fluidically communicates with the fuel cell stack (10) and which serves for supplying anode gas from an anode gas store (22) to the fuel cell stack (10), c) a cathode gas path (30) which fluidically communicates with the fuel cell stack (10) and which serves for supplying cathode gas from a cathode gas store (32) to the fuel cell stack (10), d) a cooling fluid path (40) which fluidically communicates with the fuel cell stack (10) and which serves for supplying cooling fluid from a cooling fluid store (42) to the fuel cell stack (10), e) a vibration generator (60) which is in data-transmitting communication with a control unit (50) and which serves for setting the fuel cell stack (10) into a vibrating state, and f) the control unit (50) for actuating the vibration generator (60) in order to set the fuel cell stack (10) into the vibrating state by means of the vibration generator (60).

The invention provides an SOFC cooling system. For the feature that not all components work in the full operation process of an SOFC, a DC step-down transformer DCDC, a fan and a condenser are connected in parallel, and a solenoid valve is installed in each parallel pipeline for controlling on/off of each pipeline according to a corresponding signal. Compared with the traditional SOFC cooling system, the constant-flow serial cooling system will reduce pressure losses and the power of a water pump; a solenoid valve is installed in each parallel pipeline for controlling on/off of each branch according to a corresponding signal; considering the cooling requirements of SOFC during start-up, power generation and shutdown, all components are cooled in parallel through reasonable design of each parallel pipeline, consequently to improve the cooling effect and reduce the energy consumption; the invention also discloses a fuel cell and hybrid vehicle.

A fuel cell vehicle is mounted with a fuel cell system including a fuel cell stack and a battery. The fuel cell vehicle controls operation of the fuel cell system with an ECU, to perform standby power generation from activation to when travel is allowed and to perform power generation during operation of the fuel cell vehicle after travel has been allowed. In an activation method, the power generation current is increased in accordance with a low-temperature efficiency rate during the power generation during operation, the battery is charged and the power generation current is increased in accordance with a standby current increase rate that is lower than the low-temperature efficiency rate during the standby power generation.