A method of controlling an air compressor motor for a fuel cell vehicle is provide. The method includes calculating a counter electromotive force constant of the air compressor motor based on a voltage and a current of the air compressor motor for the fuel cell vehicle supplying air to a fuel cell stack and a rotation speed of the air compressor motor. The method additionally includes determining whether a permanent magnet of the air compressor motor is demagnetized based on a result of comparison between the calculated counter electromotive force constant value and a pre-set counter electromotive force constant design value.

A method of controlling an air compressor motor for a fuel cell vehicle is provide. The method includes calculating a counter electromotive force constant of the air compressor motor based on a voltage and a current of the air compressor motor for the fuel cell vehicle supplying air to a fuel cell stack and a rotation speed of the air compressor motor. The method additionally includes determining whether a permanent magnet of the air compressor motor is demagnetized based on a result of comparison between the calculated counter electromotive force constant value and a pre-set counter electromotive force constant design value.

An air handling system for a fuel cell stack includes a pneumatic storage device disposed downstream from a compressor, a flow control valve system configured to operatively couple an inlet of the pneumatic storage device to an outlet of the compressor and configured to operatively couple an outlet of the pneumatic storage device to an inlet of the fuel cell stack, and a controller configured to, in response to a power demand being greater than a threshold, cause the flow control valve to open to increase a flow rate of air from the pneumatic storage device to the fuel cell stack.

An air handling system for a fuel cell stack includes a pneumatic storage device disposed downstream from a compressor, a flow control valve system configured to operatively couple an inlet of the pneumatic storage device to an outlet of the compressor and configured to operatively couple an outlet of the pneumatic storage device to an inlet of the fuel cell stack, and a controller configured to, in response to a power demand being greater than a threshold, cause the flow control valve to open to increase a flow rate of air from the pneumatic storage device to the fuel cell stack.

A method and system of controlling hydrogen purge are provided. The method includes estimating an air supply rate supplied to a fuel cell stack and then executing hydrogen purge based on the estimated air supply rate.

A flame-assisted fuel cell gas turbine hybrid system including a first combustor, a second combustor, and a flame-assisted solid oxide fuel cell configured to receive syngas from the first combustor, react the syngas with oxygen ions to yield carbon dioxide and water, and provide unreacted syngas to the second combustor. The first combustor is configured to receive heated compressed air from an aircraft engine compressor and the second combustor is configured to provide heated air to an aircraft engine gas turbine to generate mechanical power.

A flame-assisted fuel cell gas turbine hybrid system including a first combustor, a second combustor, and a flame-assisted solid oxide fuel cell configured to receive syngas from the first combustor, react the syngas with oxygen ions to yield carbon dioxide and water, and provide unreacted syngas to the second combustor. The first combustor is configured to receive heated compressed air from an aircraft engine compressor and the second combustor is configured to provide heated air to an aircraft engine gas turbine to generate mechanical power.

A gas turbine engine includes a fuel cell assembly including a fuel cell stack and defining a fuel cell assembly operating parameter, a fuel source, and a turbomachine. The turbomachine includes a compressor section, a combustor, and a turbine section arranged in serial flow order. The combustor is configured to receive a flow of fuel from the fuel source and further configured to receive output products from the fuel cell stack. A controller is configured to perform operations including receiving data indicative of system operation conditions, determining a set of fuel cell operating conditions to move the system emission output into or maintain the system emission output within an emissions range, and controlling the fuel cell assembly operating parameter according to the determined set of fuel cell operating conditions.

A gas turbine engine includes a fuel cell assembly including a fuel cell stack and defining a fuel cell assembly operating parameter, a fuel source, and a turbomachine. The turbomachine includes a compressor section, a combustor, and a turbine section arranged in serial flow order. The combustor is configured to receive a flow of fuel from the fuel source and further configured to receive output products from the fuel cell stack. A controller is configured to perform operations including receiving data indicative of system operation conditions, determining a set of fuel cell operating conditions to move the system emission output into or maintain the system emission output within an emissions range, and controlling the fuel cell assembly operating parameter according to the determined set of fuel cell operating conditions.

A hybrid powerplant can include a fuel cell cycle system configured to generate a first power using a fuel and an oxidizer. The powerplant can also include a supercritical carbon dioxide (sCO.sub.2) cycle system operatively connected to the fuel cell cycle to receive heat from the fuel cell cycle to cause the sCO.sub.2 cycle system to generate a second power.