An epicyclic reduction gear for a turbomachine includes a sun gear that is rotatable about a first axis and a ring gear surrounding the sun gear and also rotatable about the first axis. The ring gear is secured to a ring gear carrier that rotates a fan shaft. At least one planet gear is rotatable about a second axis and is meshed with the sun gear and the ring gear. The planet gear is guided in rotation about the second axis relative to a bearing of the planet carrier. A piece of equipment comprising a rotor. The piece of equipment is attached to the bearing of the planet carrier and has a rotor rotated by the ring gear carrier.

An epicyclic reduction gear for a turbomachine includes a sun gear that is rotatable about a first axis and a ring gear surrounding the sun gear and also rotatable about the first axis. The ring gear is secured to a ring gear carrier that rotates a fan shaft. At least one planet gear is rotatable about a second axis and is meshed with the sun gear and the ring gear. The planet gear is guided in rotation about the second axis relative to a bearing of the planet carrier. A piece of equipment comprising a rotor. The piece of equipment is attached to the bearing of the planet carrier and has a rotor rotated by the ring gear carrier.

A device for driving an integrated generator from an accessories relay box of a turbomachine. The device includes first and second electric motors arranged to transfer electric power from one to the other, one or more controllers configured for controlling said electric motors, and an epicyclic reduction gear train. The gear train includes a first element intended to be coupled to the accessories relay box, a second element intended to be coupled to the generator, and a third element driven to rotate by said first electric motor. The control means are configured to modify the speed of rotation of the third element in such a way that the second element is driven to rotate at a constant speed.

A turbomachine has an electric machine, and a starter-generator incorporating a second electric machine configured to operate as a starter and a generator. The the electric machine and the generator-starter are arranged to transfer electric power between there. A planetary gear reduction device has a first element coupled to an accessory relay housing, a second element coupled to the starter-generator, a third element rotated by the electric machine, control means configured to modify the speed of rotation of the first electric machine and the starter-generator so as to provide the starter-generator with a maximum torque in starter mode. The planetary gear reduction device also modifies the speed of rotation of the first electric machine such that the starter-generator is driven at a constant speed in generator mode.

In one embodiment, a plant control apparatus includes a first stop controller configured to, when stopping a plant, stop a steam turbine to start to drop rotating speed of a second shaft of the steam turbine from rated speed, and start to drop rotating speed of a first shaft of a gas turbine from the rated speed while continuing combustion of a combustor after the stop of the steam turbine. The apparatus further includes a second stop controller configured to shut off fuel of the combustor to stop the gas turbine when the rotating speed of the first shaft drops to first speed. The second stop controller stops the gas turbine such that the rotating speed of the first shaft catches up with the rotating speed of the second shaft at second speed that is equal to or lower than the first speed and a clutch is engaged.

Systems and methods to pump fracturing fluid into a wellhead may include a gas turbine engine including a compressor turbine shaft connected to a compressor, and a power turbine output shaft connected to a power turbine. The compressor turbine shaft and the power turbine output shaft may be rotatable at different rotational speeds. The systems may also include a transmission including a transmission input shaft connected to the power turbine output shaft and a transmission output shaft connected to a hydraulic fracturing pump. The systems may also include a fracturing unit controller configured to control one or more of the rotational speeds of the compressor turbine shaft, the power turbine output shaft, or the transmission output shaft based at least in part on target signals and fluid flow signals indicative of one or more of pressure or flow rate associated with fracturing fluid pumped into the wellhead.

An aircraft propulsion system and computing system are provided. The propulsion system includes a low pressure (LP) spool and a core engine having a high pressure (HP) spool. A frame is positioned in serial flow arrangement between an HP turbine and an LP turbine. The frame includes an inter-turbine burner including a strut forming an outlet opening into a core flowpath of the propulsion system. A first fuel system is configured to flow a liquid fuel to a combustion section for generating first combustion gases. A second fuel system is configured to flow a gaseous fuel to the core flowpath via the inter-turbine burner for generating second combustion gases. The propulsion system forms a rated power output ratio of the core engine and the inter-turbine burner with the LP spool between 1.5 and 5.7.

There is provided a gas turbine engine comprising a low pressure shaft and a high pressure shaft; wherein the low pressure shaft connects a fan to a fan drive turbine, and the high pressure shaft connects a high pressure turbine to a compressor section. The low pressure shaft and the high pressure shaft are arranged such that when operating at idle the idle shaft speed ratio is greater than 6.05. The idle shaft speed ratio is the ratio of the speed of the high pressure shaft to the speed of the low pressure shaft at idle conditions.

A hybrid propulsion system for an aircraft can include a propulsor assembly having at least one propulsor and a power generation system. The power generation system can include a first power assembly, a second power assembly, a first electric machine, and a second electric machine. The first power assembly can be drivingly coupled to the first electric machine to produce a first amount of electric power. The second power assembly can be drivingly coupled to the second electric machine to produce a second amount of electric power. A controller can be operably coupled to the first power assembly, the first electric machine, or both and to the second power assembly, the second power assembly, or both. The controller can be configured to combine at least a portion of the first and second amount of power for electric transfer to the propulsor assembly.

A system includes a gas turbine engine and a controller operable to determine a closing threshold with respect to an upper limit and an opening threshold with respect to a lower limit of a movement range of an effector of the gas turbine engine based on an on-board model, where the upper limit and the lower limit are defined for a target parameter of the gas turbine engine. The controller determines a projected state of the target parameter absent a correction command to the effector, applies a closing correction to the effector based on determining that the projected state of the target parameter would result in being above the closing threshold, and applies an opening correction to the effector based on determining that the projected state of the target parameter would result in being below the opening threshold.