Disclosed is a control apparatus for an electric power generation system. The electric power generation system is configured to generate electric power and thereby charge a secondary battery that is an electric power source of a motor included in an electric drive system. The electric drive system further includes an inverter circuit for driving the motor and a power transmission unit for transmitting electric power from the secondary battery to the inverter circuit. The control apparatus includes a temperature acquisition unit and a power generation control unit. The temperature acquisition unit is configured to acquire a temperature of the power transmission unit. The power generation control unit is configured to control the electric power generation system to generate electric power and thereby charge the secondary battery when the temperature of the power transmission unit acquired by the temperature acquisition unit is higher than or equal to a predetermined threshold temperature.

Examples described herein provide a computer-implemented method that includes providing the hybrid electric engine, the hybrid electric engine having a gas generating core and an electric machine powered by electric energy. The method further includes determining, by a processing device, whether a use of the electric energy will increase time on wing of the hybrid electric engine of the aircraft a threshold amount. The method further includes, responsive to determining that the use of energy will increase time on wing the threshold amount, apportioning the electric energy from a battery system of the aircraft to increase the time on wing.

Examples described herein provide a computer-implemented method that includes providing the hybrid electric engine, the hybrid electric engine having a gas generating core and an electric machine powered by electric energy. The method further includes determining, by a processing device, whether a use of the electric energy will increase time on wing of the hybrid electric engine of the aircraft a threshold amount. The method further includes, responsive to determining that the use of energy will increase time on wing the threshold amount, apportioning the electric energy from a battery system of the aircraft to increase the time on wing.

A hybrid electric propulsion system includes a gas turbine engine having a low speed spool and a high speed spool. The low speed spool includes a low pressure compressor and a low pressure turbine, and the high speed spool includes a high pressure compressor and a high pressure turbine. The hybrid electric propulsion system also includes an energy storage system, an electric motor configured to augment rotational power of the high speed spool, and a controller. The controller is operable to detect a start condition of the gas turbine engine, control power delivery from the energy storage system to the electric motor based on detecting the start condition, and provide a compressor stall margin using a power-assist provided by the electric motor to the high speed spool over a targeted speed range during starting of the gas turbine engine.

A hybrid electric propulsion system includes a gas turbine engine having a low speed spool and a high speed spool. The low speed spool includes a low pressure compressor and a low pressure turbine, and the high speed spool includes a high pressure compressor and a high pressure turbine. The hybrid electric propulsion system also includes an energy storage system, an electric motor configured to augment rotational power of the high speed spool, and a controller. The controller is operable to detect a start condition of the gas turbine engine, control power delivery from the energy storage system to the electric motor based on detecting the start condition, and provide a compressor stall margin using a power-assist provided by the electric motor to the high speed spool over a targeted speed range during starting of the gas turbine engine.

One embodiment is an electric drive system for an aircraft including a motor, a gear box associated with the motor, and a cooling fan for drawing air into the unit across an electronic component to cool the electronic component and for expelling air into an oil cooler for cooling oil contained therein. The electric drive system further includes an oil distribution system for distributing oil cooled by the oil cooler to at least one motor and at least one gearbox, the distributed oil being used to cool the motor and the gearbox, a reservoir for collecting the distributed oil after it has been used to cool the motor and the gearbox, and at least one structural element for retaining the motor, gearbox, the cooling fan, the oil distribution system, and the reservoir together as a unit.

One embodiment is an electric drive system for an aircraft including a motor, a gear box associated with the motor, and a cooling fan for drawing air into the unit across an electronic component to cool the electronic component and for expelling air into an oil cooler for cooling oil contained therein. The electric drive system further includes an oil distribution system for distributing oil cooled by the oil cooler to at least one motor and at least one gearbox, the distributed oil being used to cool the motor and the gearbox, a reservoir for collecting the distributed oil after it has been used to cool the motor and the gearbox, and at least one structural element for retaining the motor, gearbox, the cooling fan, the oil distribution system, and the reservoir together as a unit.

A ducted propulsion assembly for an aircraft includes a duct and a plurality of stators. The distal ends of the stators are coupled to the duct. The ducted propulsion assembly includes a line replaceable centerbody assembly isostatically coupled to the proximal ends of the stators. The line replaceable centerbody assembly includes one or more electric motors driving an output driveshaft. The ducted propulsion assembly also includes a proprotor assembly interchangeably coupled to and rotatable with the output driveshaft of the line replaceable centerbody assembly. The proprotor assembly is rotatable in a rotational plane to generate thrust.

A ducted propulsion assembly for an aircraft includes a duct and a plurality of stators. The distal ends of the stators are coupled to the duct. The ducted propulsion assembly includes a line replaceable centerbody assembly isostatically coupled to the proximal ends of the stators. The line replaceable centerbody assembly includes one or more electric motors driving an output driveshaft. The ducted propulsion assembly also includes a proprotor assembly interchangeably coupled to and rotatable with the output driveshaft of the line replaceable centerbody assembly. The proprotor assembly is rotatable in a rotational plane to generate thrust.

A method for controlling a thermal and electrical power plant for setting in motion at least one rotary member of a rotorcraft, the power plant comprising at least one heat engine and an electrical system provided with at least one electric machine. The method comprises: selecting, with a selector, an operating mode chosen from several operating modes; determining a density altitude and comparing, with a controller, the current density altitude and a threshold density altitude; and controlling, with the controller, the at least one electric machine depending on at least the chosen operating mode as well as the comparison and a necessary power to be supplied to the power transmission system.