An electric power system of a moving object includes a first polyphase rotating electric machine, a second polyphase rotating electric machine, a first polyphase terminal unit, a second polyphase terminal unit, a first polyphase cable, and a second polyphase cable. Each of the first and second polyphase terminal units includes a first phase terminal, a second phase terminal, and a third phase terminal. The first distance is smaller than the second distance that is smaller than the third distance. The fourth distance is smaller than the fifth distance that is smaller than the sixth distance.

When the supply of electric power from a first power generation device to a first power supply circuit is cut off, a control device causes electric power to be supplied from a second power generation device to between the first power generation device and a contactor device via a precharge circuit and the contactor device, determines whether or not a short circuit has occurred between the first power generation device and the contactor device, and thereafter connects the first power supply circuit and a second power supply circuit to each other.

An electrical power supply system is equipped with a first switching device disposed on a first wire of an electrical power supply circuit, a second switching device disposed on a second wire of the electrical power supply circuit, a third switching device disposed on a third wire that bypasses the first switching device, a fourth switching device disposed on a fourth wire that is connected to the third wire and the second wire, and resistors disposed in at least two portions from among a first portion on the third wire, a second portion on the fourth wire, and a third portion on the third wire.

When the supply of DC power from a first power generation device to a first power supply circuit is cut off, a control device disconnects the first power generation device from the first power supply circuit and a connection circuit using a contactor device, thereafter connects the first power supply circuit and a second power supply circuit to each other, causes electric power to be supplied from a second power generation device to between the first power generation device and the contactor device via a precharge circuit, and determines whether or not a short circuit has occurred between the first power generation device and the contactor device.

Hybrid-electric aircraft and a series hybrid powertrain configured to power the aircraft for a medium-haul flight. The series hybrid power train includes a plurality of energy storage units, at least one range extending generator, and a plurality of electric propulsors, each coupled to a distribution bus. The electric propulsors can produce a maximum thrust of at least 15 MW. During a cruise regime, the hybrid-electric aircraft can have an airspeed of at least 0.7 Mach at an altitude of less than 32000 feet, and the plurality of electric propulsors can have a fan pressure ratio of between 1.15 and 1.19. The hybrid-electric aircraft can have a degree of hybridization of at least 25% for the medium-haul flight and carbon dioxide equivalent (CO.sub.2e) well-to-wake greenhouse gas (GHG) emissions less than 0.25 lbs/Available Seat Mile (ASM).

Hybrid-electric aircraft and a series hybrid powertrain configured to power the aircraft for a medium-haul flight. The series hybrid power train includes a plurality of energy storage units, at least one range extending generator, and a plurality of electric propulsors, each coupled to a distribution bus. The electric propulsors can produce a maximum thrust of at least 15 MW. During a cruise regime, the hybrid-electric aircraft can have an airspeed of at least 0.7 Mach at an altitude of less than 32000 feet, and the plurality of electric propulsors can have a fan pressure ratio of between 1.15 and 1.19. The hybrid-electric aircraft can have a degree of hybridization of at least 25% for the medium-haul flight and carbon dioxide equivalent (CO.sub.2e) well-to-wake greenhouse gas (GHG) emissions less than 0.25 lbs/Available Seat Mile (ASM).

An aircraft control system and method for controlling electrical power distribution in an aircraft are disclosed. The aircraft control system and method obtain state signals from electrical systems in the aircraft, control characteristics of a power source, and control characteristics of the electrical systems. The control characteristics of the electrical systems are dependent on a flight phase status of the aircraft. Output control data is generated, based on the control characteristics and state signals, and used to control electrical power distribution in the aircraft.

An aircraft control system and method for controlling electrical power distribution in an aircraft are disclosed. The aircraft control system and method obtain state signals from electrical systems in the aircraft, control characteristics of a power source, and control characteristics of the electrical systems. The control characteristics of the electrical systems are dependent on a flight phase status of the aircraft. Output control data is generated, based on the control characteristics and state signals, and used to control electrical power distribution in the aircraft.

An electrical power-transfer system for an engine includes first and second engine shafts. The system also includes a planetary gear system having a sun gear, a ring gear, a plurality of planetary gears enmeshed with the sun gear and the ring gear, and a carrier supporting the plurality of planetary gears, where the carrier is configured for connection to be driven by the first engine shaft. The system further includes a first electrical machine connected to be driven by the ring gear to generate electrical power, a second electrical machine connected to drive the sun gear, and a third electrical machine configured to receive electrical power generated by the first electrical machine and operable as a motor to drive the second engine shaft.

An electrical power-transfer system for an engine includes first and second engine shafts. The system also includes a planetary gear system having a sun gear, a ring gear, a plurality of planetary gears enmeshed with the sun gear and the ring gear, and a carrier supporting the plurality of planetary gears, where the carrier is configured for connection to be driven by the first engine shaft. The system further includes a first electrical machine connected to be driven by the ring gear to generate electrical power, a second electrical machine connected to drive the sun gear, and a third electrical machine configured to receive electrical power generated by the first electrical machine and operable as a motor to drive the second engine shaft.