A gas turbine engine including a compressor has a first compressor section and a second compressor section, a combustor fluidly connected to the compressor, and a turbine fluidly connected to the combustor. The turbine includes a first turbine section and a second turbine section. A first shaft connects the first compressor section and the first turbine section. A second shaft connects the second compressor section and the second turbine section. A fan is connected to the first shaft via a geared architecture. The first shaft includes at least one magnetic section. An electromagnet is disposed radially outward of the first shaft at an axial location of the at least one magnetic section, relative to an axis defined by the gas turbine engine.

Methods and systems for controlling windmilling in an engine are described. An electric starter motor is coupled to the engine, a circuit element is coupled to the electric starter engine and to a DC signal source, and a control system coupled to the engine and to the circuit element. The control system is configured for: determining whether the engine is in a windmilling state; when the engine is in a windmilling state, commanding the circuit element to apply a DC signal to the electric starter motor; and modulating the DC signal applied to the electric starter motor to control a level of rotational motion of the engine.

A method of operating a twin engine helicopter power plant, the power plant comprising: two turboshaft engines each having an engine shaft with a turbine at a distal end and a one-way clutch at a proximal end; a gear box having an input driven by the one way clutch of each engine and an output driving a helicopter rotor; a bypass clutch disposed between the proximal end of each engine shaft and the input of the gear box; and power plant management system controls for activating the bypass clutch; the method comprising: detecting when a rotary speed of an associated engine shaft is less than a rotary speed of the gear box input; activating the bypass clutch to drive the associated engine shaft using the rotation of the gear box input; and starting an associated engine by injecting fuel when the bypass clutch is activated.

A gas turbine engine includes a compressor having a first compressor section and a second compressor section, a combustor fluidly connected to the compressor, and a turbine fluidly connected to the combustor. The turbine has a first turbine section and a second turbine section. A first shaft connects the first compressor section and the first turbine section. A second shaft connects the second compressor section and the second turbine section. A fan is connected to the first shaft via a geared architecture. A low speed accessory gearbox is interfaced with the first shaft via a mechanical interface. The low speed accessory gearbox includes a mechanical brake.

An information generating device includes a control unit for causing a motor to rotate a pinion gear meshing with a ring gear while a predetermined braking force is applied to brake rotation of a turnable part of a wind turbine, thereby causing a fastening part to deform, where the fastening part is provided to fixedly attach the motor to a target part, a deformation amount obtaining unit for obtaining an amount of deformation experienced by the fastening part, and an information generating unit for generating correlation information indicating a correspondence between a driving torque of the motor and the amount of deformation experienced when the driving torque is used to rotate the motor.

A gas turbine engine has an engine static structure and at least one component rotatable relative to the engine static structure about an engine axis of rotation. A fan is coupled to at least one component for rotation about the engine axis of rotation. An actuator is mounted to the engine static structure, wherein the actuator is activated to prevent the fan from rotation and is inactivated to allow the fan to rotate. A method for preventing rotation of a fan in a gas turbine engine is also disclosed.

A turbine engine includes a fan connected to a fan shaft, a combustion chamber, and an electric motor/generator in communication with the fan shaft. A controller is configured to direct power into the electric motor/generator during engine accelerations from steady state such that air flow to the combustion chamber is increased. The controller is further configured to direct power out of the electric motor/generator during engine decelerations from steady state such that air flow to the combustion chamber is decreased.

A gas turbine engine has an engine static structure. At least one component rotatable relative to the engine static structure about an engine axis of rotation. A fan is coupled to at least one component for rotation about the engine axis of rotation. An actuator is mounted to the engine static structure, wherein the actuator is activated to prevent the fan from rotation and is inactivated to allow the fan to rotate. A method for preventing rotation of a fan in a gas turbine engine is also disclosed.

An improved HVAC vent is disclosed. The vent may include an air turbine positioned within a passageway for selectively enabling and preventing airflow. In use, the air turbine is selectively operable between first and second states. In the first state, the air turbine may be freely rotatable, via the airflow, so that the received airflow can move through the passageway. In the second state, rotation of the air turbine is controlled or prevented so that the received airflow is inhibited or substantially inhibited from moving through the passageway. The vent may also include a motor. In use, the motor may act an energy generator and as an active brake so that in the first state, rotation of the air turbine is used to charge a power storage unit, and in the second state, the motor limits rotation of the air turbine.

An electric generator includes a turbine wheel configured to receive process gas and rotate in response to expansion of the process gas flowing into an inlet of the turbine wheel. A rotor is coupled to the turbine wheel and can rotate with the turbine wheel in a stator. The electric generator generates a current upon rotation of the rotor within the stator. A power electronics system is electrically connected to an electrical output of the electric generator and receives alternating current from the electric generator. A fast stop valve resides proximate and upstream from an inlet conduit of the electric generator. The fast stop valve can quickly shut upon detection of a fault condition at the power electronics or the grid, to prevent an overspeed of the rotor.