Examples provide an electric propulsion system; the system comprising a nacelle comprising an aerodynamic annular housing defining an internal annular volume and defining an inner duct, only a single one fan stage comprising a fan bearing a plurality of aerodynamic surfaces/blades to generate thrust, and a powertrain comprising at least one electric motor to drive the fan and at least one electrical power source to power the electric motor; and wherein the fan is disposed within the inner duct and the powertrain is disposed within the internal annular volume.

Examples provide electric propulsion systems; such a system comprising: a. a nacelle comprising an aerodynamic annular housing defining an internal annular volume and defining an inner duct, b. at least one fan stage comprising a fan bearing a plurality of aerodynamic surfaces/blades to generate thrust mounted within a fan shroud, and c. a powertrain comprising at least one electric motor to drive the fan shroud and at least one electrical power source to power the electric motor; and d, wherein i. the fan shroud is disposed within the inner duct, ii. at least part of the powertrain is disposed within the internal annular volume, iii. the at least one electric motor is disposed within the central hub and iv. the hub-to-tip ratio is between 0.1 and 0.4, preferably, between 0.2 and 0.3.

Examples provide electric propulsion systems; such a system comprising: a. a nacelle comprising an aerodynamic annular housing defining an internal annular volume and defining an inner duct, b. at least one fan stage comprising a fan bearing a plurality of aerodynamic surfaces/blades to generate thrust mounted within a fan shroud, and c. a powertrain comprising at least one electric motor to drive the fan shroud and at least one electrical power source to power the electric motor; and d, wherein i. the fan shroud is disposed within the inner duct, ii. at least part of the powertrain is disposed within the internal annular volume, iii. the at least one electric motor is disposed within the central hub and iv. the hub-to-tip ratio is between 0.1 and 0.4, preferably, between 0.2 and 0.3.

An integrated hydrogen-electric engine includes a hydrogen fuel-cell; a hydrogen fuel source; an electric motor assembly disposed in electrical communication with the fuel-cell; an air compressor system configured to be driven by the motor assembly, and a cooling system having a heat exchanger radiator in a duct of the cooling system, and configured to direct an air stream including an air stream from the air compressor through the radiator, wherein an exhaust stream from a cathode side of the fuel-cell is fed via a flow control nozzle into the air stream in the cooling duct downstream of the radiator.

An integrated hydrogen-electric engine includes a hydrogen fuel-cell; a hydrogen fuel source; an electric motor assembly disposed in electrical communication with the fuel-cell; an air compressor system configured to be driven by the motor assembly, and a cooling system having a heat exchanger radiator in a duct of the cooling system, and configured to direct an air stream including an air stream from the air compressor through the radiator, wherein an exhaust stream from a cathode side of the fuel-cell is fed via a flow control nozzle into the air stream in the cooling duct downstream of the radiator.

An electrically-powered turbine assembly includes a fixed housing; an air compressor including a compressor stator fixed to the housing; a turbine including a turbine stator fixed to the housing; a central shaft supported by the compressor stator and affixed to the turbine stator; an electric motor including an electric motor stator fixed to the central shaft, said electric motor having a rotating shell; an air compressor rotor affixed to the rotating electric motor shell; and a turbine rotor affixed to the rotating electric motor shell. The electrically-powered turbine assembly preferably includes one or more fuel cells as an electric power source. The electrically-powered turbine assembly may be used to power an aircraft.

A propulsion system for an aircraft as disclosed herein may include a nacelle, a shaft positioned centrally within a cylindrical passageway of the nacelle, a fan coupled to one end of the shaft, a turbine coupled to an opposite end of the shaft, an electric motor coupled to the shaft, a compressor positioned within the cylindrical passageway, and a solid oxide fuel cell positioned with a hollow ring-shaped interior of the nacelle. The hollow ring-shaped interior may surround and be isolated from the cylindrical passageway. The turbine may be configured to provide primary torque to the shaft while the electric motor may be configured to provide additional torque to the shaft. The electric motor may be powered an electric output of the solid oxide fuel cell while the turbine may be powered at least in part by output gases from the solid oxide fuel cell.

A propulsion system for an aircraft as disclosed herein may include a nacelle, a shaft positioned centrally within a cylindrical passageway of the nacelle, a fan coupled to one end of the shaft, a turbine coupled to an opposite end of the shaft, an electric motor coupled to the shaft, a compressor positioned within the cylindrical passageway, and a solid oxide fuel cell positioned with a hollow ring-shaped interior of the nacelle. The hollow ring-shaped interior may surround and be isolated from the cylindrical passageway. The turbine may be configured to provide primary torque to the shaft while the electric motor may be configured to provide additional torque to the shaft. The electric motor may be powered an electric output of the solid oxide fuel cell while the turbine may be powered at least in part by output gases from the solid oxide fuel cell.

A power supply system of an aircraft includes a fuel cell that generates electrical energy, a converter device including a mode switch device that supplies power to a first motor device through a first output terminal and switches a connection between an output node of the fuel cell and the first output terminal, a first battery device that supplies a voltage from a first battery to a second motor device through a second output terminal and connects the second output terminal with the first output terminal under control of the mode switch device, and a processor that controls the mode switch device to enter an emergency mode when detecting an error in the converter device or the first battery device and connects the first output terminal with the second output terminal.

A power supply system of an aircraft includes a fuel cell that generates electrical energy, a converter device including a mode switch device that supplies power to a first motor device through a first output terminal and switches a connection between an output node of the fuel cell and the first output terminal, a first battery device that supplies a voltage from a first battery to a second motor device through a second output terminal and connects the second output terminal with the first output terminal under control of the mode switch device, and a processor that controls the mode switch device to enter an emergency mode when detecting an error in the converter device or the first battery device and connects the first output terminal with the second output terminal.