The present disclosure relates to an architecture of a propulsion system of a multi-engine helicopter comprising turboshaft engines connected to a power transmission gearbox, characterized in that it comprises: at least one hybrid turboshaft engine capable of operating in at least one standby mode during a stable cruise flight of the helicopter; at least two systems for controlling each hybrid turboshaft engine, each system comprising an electric machine connected to the hybrid turboshaft engine and suitable for rotating the gas generator thereof, and at least one source of electrical power for the electric machine, each reactivation system being configured such that it can drive the turboshaft engine in at least one operating mode among a plurality of predetermined modes.

The present disclosure relates to an architecture of a propulsion system of a multi-engine helicopter comprising turboshaft engines connected to a power transmission gearbox, characterized in that it comprises: at least one hybrid turboshaft engine capable of operating in at least one standby mode during a stable cruise flight of the helicopter; at least two systems for controlling each hybrid turboshaft engine, each system comprising an electric machine connected to the hybrid turboshaft engine and suitable for rotating the gas generator thereof, and at least one source of electrical power for the electric machine, each reactivation system being configured such that it can drive the turboshaft engine in at least one operating mode among a plurality of predetermined modes.

A steam turbine plant is provided with: a boiler; a fuel valve; a low-temperature steam generation source; a steam turbine; a main steam line that guides steam generated in the boiler to the steam turbine; a main steam adjustment valve that is provided to the main steam line; a low-temperature steam line that guides low-temperature steam from the low-temperature generation source to a position closer to the steam turbine-side than the main steam adjustment valve in the main steam line; a low-temperature steam valve provided to the low-temperature steam line; and a control device. During a stopping process of the steam turbine plant, the control device sends a command to close the fuel valve, and then sends a command to open the low-temperature steam valve.

A steam turbine plant is provided with: a boiler; a fuel valve; a low-temperature steam generation source; a steam turbine; a main steam line that guides steam generated in the boiler to the steam turbine; a main steam adjustment valve that is provided to the main steam line; a low-temperature steam line that guides low-temperature steam from the low-temperature generation source to a position closer to the steam turbine-side than the main steam adjustment valve in the main steam line; a low-temperature steam valve provided to the low-temperature steam line; and a control device. During a stopping process of the steam turbine plant, the control device sends a command to close the fuel valve, and then sends a command to open the low-temperature steam valve.

A gas turbine engine includes a combustor having a combustor air inlet, an axial-centrifugal compressor, a shroud, a secondary flow duct, and a valve. The shroud surrounds at least a portion of the axial-centrifugal compressor and has a surge bleed plenum defined therein that is in fluid communication with, and receives compressed air from, the axial compressor outlet. The secondary airflow duct has a duct inlet that is in fluid communication with the surge bleed plenum, and a duct outlet that is in fluid communication with the combustor air inlet. The valve is mounted on the secondary airflow duct and is movable between a closed position, in which the secondary airflow duct does not provide fluid communication between the surge bleed plenum and the combustor air inlet, and an open position, in which the secondary airflow duct provides fluid communication between the surge bleed plenum and the combustor air inlet.

A gas turbine engine includes a combustor having a combustor air inlet, an axial-centrifugal compressor, a shroud, a secondary flow duct, and a valve. The shroud surrounds at least a portion of the axial-centrifugal compressor and has a surge bleed plenum defined therein that is in fluid communication with, and receives compressed air from, the axial compressor outlet. The secondary airflow duct has a duct inlet that is in fluid communication with the surge bleed plenum, and a duct outlet that is in fluid communication with the combustor air inlet. The valve is mounted on the secondary airflow duct and is movable between a closed position, in which the secondary airflow duct does not provide fluid communication between the surge bleed plenum and the combustor air inlet, and an open position, in which the secondary airflow duct provides fluid communication between the surge bleed plenum and the combustor air inlet.

A system includes a gas turbine engine of an aircraft, the gas turbine engine having a low speed spool, a high speed spool, and a combustor. The system also includes a low spool motor configured to augment rotational power of the low speed spool and a high spool motor configured to augment rotational power of the high speed spool. The system further includes a controller configured to cause fuel flow. The controller is configured to control a thrust response of the gas turbine engine to a thrust target between zero and a thrust level to move the aircraft during engine start and during engine idle. The controller is also configured to control the low spool motor to drive rotation of the low speed spool responsive to a thrust command while the controller does not command fuel flow to the combustor.

A system includes a gas turbine engine of an aircraft, the gas turbine engine having a low speed spool, a high speed spool, and a combustor. The system also includes a low spool motor configured to augment rotational power of the low speed spool and a high spool motor configured to augment rotational power of the high speed spool. The system further includes a controller configured to cause fuel flow. The controller is configured to control a thrust response of the gas turbine engine to a thrust target between zero and a thrust level to move the aircraft during engine start and during engine idle. The controller is also configured to control the low spool motor to drive rotation of the low speed spool responsive to a thrust command while the controller does not command fuel flow to the combustor.

An air starter for an engine, such as a turbine engine, that includes a turbine for rotatably extracting mechanical power from a flow of fluid. The turbine includes a drive shaft that can be coupled to an output shaft to provide a rotational output. The interface between the drive shaft and the output shaft can be offset.

Provided is a startup control device for adjusting a startup schedule during startup of a power generation plant. This startup control device is provided with: a determining unit which, for a prescribed physical quantity that restricts the startup of the power generation plant, determines, on the basis of a predicted value of a physical quantity corresponding to the elapsed time from startup when the power generation plant has started up on the basis of a prescribed optimal startup schedule, and an observed value of the physical quantity acquired during the startup of the power generation plant, whether the observed value will exceed the predicted value; a speed adjusting unit which, if the determining unit determines that the observed value will exceed the predicted value, issues an instruction to decelerate the speed of progress of elapsed time from the startup in the optimal startup schedule; and a startup timer which progresses the elapsed time from the startup at a speed based on the instruction.