A fuel cell system includes a fuel cell, an anode gas supply system, an anode gas circulatory system, a cathode gas supply-discharge system, a gas-liquid discharge passage, a gas-liquid discharge valve configured to open and close the gas-liquid discharge passage, a flow-rate acquisition portion, and a controlling portion. After the controlling portion instructs the gas-liquid discharge valve to be opened, the controlling portion executes a normal-abnormality determination such that, when a discharge-gas flow rate of anode gas is a predetermined normal reference value or more, the controlling portion determines that the gas-liquid discharge valve is opened normally, and when the discharge-gas flow rate is lower than the normal reference value, the controlling portion determines that the gas-liquid discharge valve is not opened normally.

A fuel cell system includes a fuel cell, an anode gas supply system, an anode gas circulatory system, a cathode gas supply-discharge system, a gas-liquid discharge passage, a gas-liquid discharge valve configured to open and close the gas-liquid discharge passage, a flow-rate acquisition portion, and a controlling portion. After the controlling portion instructs the gas-liquid discharge valve to be opened, the controlling portion executes a normal-abnormality determination such that, when a discharge-gas flow rate of anode gas is a predetermined normal reference value or more, the controlling portion determines that the gas-liquid discharge valve is opened normally, and when the discharge-gas flow rate is lower than the normal reference value, the controlling portion determines that the gas-liquid discharge valve is not opened normally.

In one or more embodiments of the novel aircraft fuel cell system without the use of a buffer battery, the fuel cell and compressor would be sized sufficiently larger for the intended application, allowing the compressor to change speeds much faster. This in turn would allow power outputs to change much quicker. If power outputs can change as quickly as the application dictates, then a buffer battery is not necessary. In one or more embodiments, because the system is mostly electronically controlled, software can be written to protect the fuel cell from instantaneous power spikes. If a large power output is suddenly requested of the fuel cell, the software can smooth out the demand curve to provide an easier load profile to follow.

In one or more embodiments of the novel aircraft fuel cell system without the use of a buffer battery, the fuel cell and compressor would be sized sufficiently larger for the intended application, allowing the compressor to change speeds much faster. This in turn would allow power outputs to change much quicker. If power outputs can change as quickly as the application dictates, then a buffer battery is not necessary. In one or more embodiments, because the system is mostly electronically controlled, software can be written to protect the fuel cell from instantaneous power spikes. If a large power output is suddenly requested of the fuel cell, the software can smooth out the demand curve to provide an easier load profile to follow.

A high efficiency hydrogen fuel system for an aircraft at high altitude which utilizes compressors to compress air to a sufficiently high pressure for the fuel cell. Liquid hydrogen is compressed and then utilized in heat exchangers to cool the compressed air, maintaining the air at a temperature low enough for the fuel cell. The hydrogen is also used to cool the fuel cell as it is also depressurized prior to its entry in the fuel cell cycle. A water condensation system allows for water removal from the airstream to reduce impacts to the atmosphere. The hydrogen fuel system may be used with VTOL aircraft, which may allow them to fly at higher elevations. The hydrogen fuel system may be used with other subsonic and supersonic aircraft, such as with asymmetric wing aircraft.

An engine assembly includes a combustor, a fuel cell stack fluidly connected to the combustor, the fuel cell stack being configured (i) to generate power using fuel and air directed into the fuel cell stack and (ii) to direct fuel and air exhaust from the fuel cell stack into the combustor, a compressor fluidly connected upstream of (i) the combustor and (ii) the fuel cell stack, the compressor being configured to generate compressed air to direct into the fuel cell stack, a turbine disposed downstream from the combustor, the turbine having a turbine inlet temperature, and a controller that is configured to control a power allocation between the fuel cell stack and the turbine based upon the turbine inlet temperature of the turbine. The combustor is configured to combust the fuel and air exhaust from the fuel cell stack into one or more gaseous combustion products that power the turbine.

An engine assembly includes a combustor, a fuel cell stack fluidly connected to the combustor, the fuel cell stack being configured (i) to generate power using fuel and air directed into the fuel cell stack and (ii) to direct fuel and air exhaust from the fuel cell stack into the combustor, a compressor fluidly connected upstream of (i) the combustor and (ii) the fuel cell stack, the compressor being configured to generate compressed air to direct into the fuel cell stack, a turbine disposed downstream from the combustor, the turbine having a turbine inlet temperature, and a controller that is configured to control a power allocation between the fuel cell stack and the turbine based upon the turbine inlet temperature of the turbine. The combustor is configured to combust the fuel and air exhaust from the fuel cell stack into one or more gaseous combustion products that power the turbine.

A fuel cell mount apparatus includes a plurality of fuel cell stacks, a pipe arrangement, a fluid adjustment part, a pressure detection part, and a control device. The pipe arrangement is individually connected to each of the fuel cell stacks. The fluid adjustment part adjusts a pressure or a flow rate of a fluid which flows through the pipe arrangement. The pressure detection part is disposed on a portion which requires a desired pressure or flow rate of the fluid in the pipe arrangement and detects the pressure of the fluid. The control device controls the fluid adjustment part on the basis of a detection result of the pressure detection part.

An engine assembly includes a combustor, a fuel cell stack integrated with the combustor, and a pre-burner system fluidly connected to the fuel cell stack. The fuel cell stack is configured to direct fuel and air exhaust from the fuel cell stack into the combustor. The pre-burner system is configured to control a temperature of an air flow directed into the fuel cell stack. The combustor is configured to combust the fuel and air exhaust from the fuel cell stack into one or more gaseous combustion products that drive a downstream turbine. The engine assembly can further include a catalytic partial oxidation convertor that is fluidly connected to the fuel cell stack. The catalytic partial oxidation convertor is configured to develop a hydrogen rich fuel stream to be directed into the fuel cell stack.

A hydrogen-electric engine includes a fuel cell stack including a plurality of fuel cells. Each fuel cell of the plurality of fuel cells includes an anode and a cathode. The hydrogen-electric engine also includes an air compressor system configured to supply compressed air to the cathode, a hydrogen fuel source configured to supply hydrogen gas, an elongated shaft supporting the air compressor system and the fuel cell stack, and a motor assembly disposed in electrical communication with the fuel cell stack. Each fuel cell generates a voltage, as an open cell voltage, by forming water with the supplied compressed air and the supplied hydrogen gas and is electrically coupled with a clamp circuit.