A dual motor system includes a first motor providing a lower speed range and a second motor providing a higher speed range, wherein the motors are coaxially arranged and aligned on and drive a common shaft, and a motor control system controlling the speed of the first motor and engaging the second motor as needed. The first motor is a variable speed motor providing a lower two-thirds of a full speed range, and the second motor is an induction motor providing the upper one-third in the form of one or more discrete fixed speeds. The system may include a transformer including a first winding tap which provides a first higher speed, and a second winding tap which provides a second higher speed. The system may also include a flow control system for automatically controlling the speed of the motors for particular applications, such as flow control in a pool.

An aircraft propulsion system includes a gas turbine engine; a generator; a storage battery; a motor which drives a rotor, using at least one of the electric power which is output from the generator and the electric power which is output from the storage battery; a detection unit which detects the number of revolutions of the engine shaft; an engine control unit which controls at least a fuel flow rate of the gas turbine engine; and a generator control unit which controls the operation of the generator. When the number of revolutions satisfies a predetermined condition, at least the generator control unit executes a control for reducing a sudden change in the number of revolutions.

An aircraft propulsion system includes a gas turbine engine; a generator; a storage battery; a motor which drives a rotor, using at least one of the electric power which is output from the generator and the electric power which is output from the storage battery; a detection unit which detects the number of revolutions of the engine shaft; an engine control unit which controls at least a fuel flow rate of the gas turbine engine; and a generator control unit which controls the operation of the generator. When the number of revolutions satisfies a predetermined condition, at least the generator control unit executes a control for reducing a sudden change in the number of revolutions.

A retaining collar is disclosed for a bayonet mount comprising a rotor disc having a male mounting member defining a pair of apertures and an auxiliary annular wheel defining a plurality of mounting slots. The retaining collar comprises a ring-shaped body and a pair of retention pins. The ring-shaped body has a pair of circumferential end portions separated by a circumferential gap, and an arcuate radial outer surface extending circumferentially between the end portions. The body is dimensioned so that the radial outer surface frictionally engages a radial inner surface of a cylindrical male mounting member in the bayonet mount. The pair of retention pins each extend radially outward from one of the circumferential end portions. Each of the retention pins are dimensioned to extend radially outward from the body through one of said apertures and one of said mounting slots.

A dual motor system includes a first motor providing a lower speed range and a second motor providing a higher speed range, wherein the motors are coaxially arranged and aligned on and drive a common shaft, and a motor control system controlling the speed of the first motor and engaging the second motor as needed. The first motor is a variable speed motor providing a lower two-thirds of a full speed range, and the second motor is an induction motor providing the upper one-third in the form of one or more discrete fixed speeds. The system may include a transformer including a first winding tap which provides a first higher speed, and a second winding tap which provides a second higher speed. The system may also include a flow control system for automatically controlling the speed of the motors for particular applications, such as flow control in a pool.

A braking system for the low pressure spool of a gas turbine engine includes a braking assembly connected to the low pressure spool and reversibly configurable between an actuated state and an unactuated state. The braking assembly in the unactuated state allows rotation of the low pressure spool without interference. The braking assembly in the actuated state applies a force opposing the rotation of the low pressure spool. A method of controlling the speed of rotation of a low pressure spool and a method of controlling the speed of rotation of low and high pressure spools are also discussed.

A control device includes a fuel equivalent value calculation unit for determining the flow rate of fuel supplied to a gas turbine in accordance with a target value deviation between an actual rotation speed and a target rotation speed, an upper limit deviation calculation unit for obtaining an upper limit deviation which is a deviation between a set upper limit output and an actual output, a lower limit deviation calculation unit for obtaining a lower limit deviation which is a deviation between a set lower limit output and the actual output, and a parameter-changing unit for changing any one parameter among the target rotation speed, the actual rotation speed, and the target value deviation so that the target value deviation decreases when the actual rotation speed decreases and the upper limit deviation is small, and so that the target value deviation increases when the actual rotation speed increases and the lower limit deviation is small.

An embodiment of an engine assembly includes a combustion turbine engine having at least a first compressor spool, a first turbine spool, a first shaft connecting the first compressor spool and the first turbine spool, and a combustor disposed in a working gas flow path between the first compressor spool and the first turbine spool. A first controller is programmed with a surge map, and configured to operate the combustion turbine engine in a range extending between a first suppressed idle mode, a second base idle mode, and a maximum takeoff power rating mode. An idle speed suppressor includes at least one idle assist motor connected to the first shaft of the combustion turbine engine. A second controller is configured to manage operation of the idle speed suppressor relative to the combustion turbine engine during times of minimum power demand, such that operating the idle speed suppressor increases a compressor speed in the first suppressed idle mode relative to a compressor speed in the second base idle mode.

The invention relates to an overspeed protection device of an aircraft engine.

A fan control circuit for controlling a fan includes a processing module, a driving module and a speed compensation module. The driving module is electrically connected to the processing module, and generates at least one driving signal to drive the fan. The speed compensation module is electrically connected to the processing module, and receives a first voltage. The first voltage is variable. The speed compensation module generates and transmits a speed-compensation parameter to the processing module according to the first voltage and a first waveform, and the processing module adjusts the driving signal according to the speed-compensation parameter.