An example system includes an electrical machine electrically configured to generate electrical energy used by one or more components of a gas-turbine engine; an energy storage system; and a controller electrically connected to the energy storage system and configured to receive electrical energy from the energy storage system, wherein, in response to the gas-turbine engine being shut off, the controller is configured to cause the electrical machine to rotate a rotor of the gas-turbine engine using the energy received from the energy storage system.

An aircraft includes a closed wing, a fuselage at least partially disposed within a perimeter of the closed wing, and one or more spokes coupling the closed wing to the fuselage. A source of electric power is disposed within or attached to the closed wing, fuselage or one or more spokes. A plurality of electric motors are disposed within or attached to the one or more spokes in a distributed configuration. Each electric motor is connected to the source of electric power. A propeller is operably connected to each of the electric motors and proximate to a leading edge of the one or more spokes. One or more processors are communicably coupled to the plurality of electric motors. A longitudinal axis of the fuselage is substantially vertical in vertical takeoff and landing and stationary flight, and substantially in a direction of a forward flight in a forward flight mode.

A hybrid turbofan engine for an aircraft, comprising a fan, an electric motor/generator and a gas generator, the engine comprising, between the fan and a splitter that separates the flows, an internal wall for delimiting an air duct, situated upstream of inlet guide vanes of a primary duct, and, upstream of outlet guide vanes, an internal upstream wall for delimiting a secondary duct, the motor/generator having a stator carried by a stator support fixed to a stator part of the engine. According to the invention, a plurality of heat pipe for cooling the motor/generator are provided, each heat pipe having an evaporation section fixed to the stator support, and a condensation section fixed to the internal wall or the internal upstream wall.

An example method of managing power in a hybrid propulsion system includes receiving, by one or more processors, a power demand that specifies an amount of power to be used to propel a vehicle that includes an electrical energy storage system (ESS) and one or more electrical generators, wherein the one or more electrical generators are configured to convert mechanical energy to electrical energy; determining, based on the power demand and a predetermined ESS output limit, a first amount of power to be sourced from the ESS and a second amount of power to be sourced from the one or more generators; and causing, by the one or more processors, the ESS to output the first amount of power onto a direct current (DC) electrical distribution bus and the one or more generators to output the second amount of power onto the DC electrical distribution bus.

A powertrain system of an aircraft includes one or more electrical components to provide electrical power to one or more electrical loads of the aircraft. The system further includes a rechargeable cryogenic heat sink containing a volume of cryogenic cooling material. The cryogenic heat sink is configured to cool the one or more electrical components. A method of operating a powertrain system of an aircraft includes generating thermal energy at one or more electrical components of the powertrain system, fluidly connecting a cryogenic heat sink to the one or more electrical components, and cooling the one or more electrical components via a volume of cryogenic cooling material of the cryogenic heat sink.

An aerial vehicle is disclosed having a hybrid drive unit and a rotor unit wherein the hybrid drive unit includes at least a combustion engine, a generator and a first electric motor and the rotor unit includes a first rotor. The combustion engine is configured to drive the generator to produce electricity, and the generator is coupled to the first electric motor in such a way that the first electric motor is feedable with electricity from the generator. The rotor unit includes a second rotor and the hybrid drive unit includes a second electric motor, wherein the generator is coupled to the second electric motor in such a way that the second electric motor is feedable with electricity from the generator. The first rotor is driven by the first electric motor and the second rotor is driven by the second electric motor.

An electrical system for connecting a rotary electric machine to de networks operating at different voltages V and W where V>W, the electric machine has N=4 polyphase winding sets. The electrical system includes a first set of N=4 ac-dc converter circuits connected in a modular multilevel configuration, each ac-dc converter circuit having a respective index n=(1, . . . , 4) and an ac interface for connection with a corresponding nth winding set, and in which the modular multilevel configuration has P=5 dc outputs each having a respective index p=(1, . . . , 5), and a set of N=4 dc-dc converter circuits each having a respective index n=(1, . . . , 4) and being configured to convert dc power between a voltage V/4 at a first dc interface and a voltage W at a second dc interface.

A rotary wing aircraft having an electrical installation including at least one thermopile for powering at least one piece of electrical load equipment. Technical specifications for the thermopile specify: a usable power for supplying to the load equipment in the range 20 W to 200 kW, a power rise time lapse lying in the range 3 s to 30 s, and a low operating time for usefully supplying a predetermined quantity of electrical energy lying in the range 10 s to 180 s. The invention applies in particular to rotary wing aircraft.

Embodiments of a propulsion system are provided herein. In some embodiments, a propulsion system for an aircraft may include an electrical power supply; a motor coupled to the electrical power supply, wherein the electrical power supply provides power to the motor; and a fan disposed proximate a rear portion of an aircraft and rotatably coupled to the motor, wherein the fan is driven by the motor.

A system for providing regenerative power for an aircraft to sustain flight includes multiple energy cells disposed within the aircraft, the energy cells being configured to supply power to a propulsion motor and electronics of the aircraft, a fan generator harnessing propeller blast created by an aircraft propeller and converting kinetic energy of the propeller blast into electrical energy, a charger receiving the electrical energy generated by the fan generator and using the electrical energy to recharge one or more of the energy cells, and a power transfer switch selectively connecting one of the energy cells to the propulsion motor and electronics of the aircraft, such that the energy cells are rotated one at a time to power the propulsion motor and electronics. During recharging, the one or more of the energy cells are disconnected by the power transfer switch.