Abstract: An electric taxi system (ETS) for an aircraft has an electric motor enclosed within a landing gear strut. A stator winding of the motor is attached to a lower structural element of the strut.

Abstract: A wedge cooling apparatus and method for cooling a rotating machine, such as a generator, disperses a spray of cooling fluid into the wedges of the generator. The spray cooling method results in a high heat transfer coefficient of about 2000-3000 W/m2C as opposed to conventional conduction cooling, which has a heat transfer coefficient of about 200-300 W/m2C. The apparatus and method of the present invention efficiently removes heat from high powered, high current density designed generators.

Abstract: An electrical power system may comprise a main generator with a rotor having field windings and at least one embedded permanent magnet. A generator control unit (GCU) may be connected to receive excitation current produced by the main generator with flux from the at least one permanent magnet. An exciter generator may be connected to be provided with excitation from the GCU. The exciter generator may provide excitation current to the field windings of the main generator. The main generator may produce output current from flux from the field windings and the at least one permanent magnet.

Abstract: An electrical motor or generator asymmetrical armature winding configuration generating a multi-phase balanced power output. Each winding group for each pole, and the conductors constituting each winding group, are chosen individually according to their magnetomotive force (MMF) vector relationship to provide a balanced power output even though the individual windings may not be balanced or symmetrical.

Abstract: A shear gear arrangement with gear teeth on the bearing liner positioned to engage complementary teeth on a shear gear main body. The bearing liner is static, while the shear gear main body mounts on the rotating drive shaft. If a failure occurs, the drive shaft displacement causes the shear gear main body gear teeth to engage the bearing liner teeth, instantaneously loading the shear section of the shaft with a sufficient torque load to shear the section as designed.

Abstract: An electrical power system architecture uses an auxiliary power unit as an electrical power source during taxi (ground idle) and approach idle (if required). Using the APU as a power source enables a low pressure spool driven electrical generator to be off-line when its speed is too low for it to operate effectively.

Abstract: A power system for a vehicle may comprise an electric machine interposed between an engine and a transmission of the vehicle. The electric machine may comprise an exciter generator with exciter armature windings surrounding an axis, a main generator with main field windings surrounding the axis so that the exciter generator and the main generator are concentric and a rotor coaxial with the axis and the rotor supporting the exciter armature windings and the main field windings. The rotor may have a first end attached to the engine power output shaft and a second end adapted to deliver mechanical power from the engine to the transmission.

Abstract: An electrical power system architecture uses an auxiliary power unit as an electrical power source during taxi (ground idle) and approach idle (if required). Using the APU as a power source enables a low pressure spool driven electrical generator to be off-line when its speed is too low for it to operate effectively.

Abstract: An electrical power system may comprise a main generator with a rotor having field windings and at least one embedded permanent magnet. A generator control unit (GCU) may be connected to receive excitation current produced by the main generator with flux from the at least one permanent magnet. An exciter generator may be connected to be provided with excitation from the GCU. The exciter generator may provide excitation current to the field windings of the main generator. The main generator may produce output current from flux from the field windings and the at least one permanent magnet.

Abstract: An electrical motor or generator asymmetrical armature winding configuration generating a multi-phase balanced power output. Each winding group for each pole, and the conductors constituting each winding group, are chosen individually according to their magnetomotive force (MMF) vector relationship to provide a balanced power output even though the individual windings may not be balanced or symmetrical.

Abstract: A shear gear arrangement with gear teeth on the bearing liner positioned to engage complementary teeth on a shear gear main body. The bearing liner is static, while the shear gear main body mounts on the rotating drive shaft. If a failure occurs, the drive shaft displacement causes the shear gear main body gear teeth to engage the bearing liner teeth, instantaneously loading the shear section of the shaft with a sufficient torque load to shear the section as designed.

Abstract: A system is provided for cooling a stator coil of a rotating machine. In one embodiment, and by way of example only, the system includes a stator core, a radial core opening, and a sleeve. The stator core has an axially extending slot formed therein, an outer circumferential surface, and an inner circumferential surface. The radial core opening extends from the stator core outer circumferential surface to the axially extending slot. The sleeve is disposed within the axial slot and configured to surround the stator coil. The sleeve has a cooling fluid supply port formed therein that is aligned with the radial core opening.

Abstract: A turbofan gas turbine propulsion engine includes a system to transfer power from the low pressure turbine to the high pressure turbine and/or extract additional load from the low pressure turbine during certain turbofan engine operational conditions. The systems include a hydrostatic power transfer system that includes a hydraulic pump and a hydraulic motor coupled to the low pressure and high pressure turbine, respectively. The systems additionally include a mechanical and electrical load shifting/loading sharing systems that use clutches and gear assemblies to share and/or shift load between the turbines.

Abstract: A rotating electrical machine, such as an aircraft starter-generator, that may be operated in either a DC motor mode or an AC generator mode. The machine includes a conventionally wound main stator that is selectively configurable as a multi-pole AC stator and a multi-pole DC stator. The machine also includes rotor windings that are configured to be selectively coupled to either an exciter or a plurality of commutator segments, and DC brushes that are selectively moveable into, and out of, electrical contact with the commutator segments, to thereby electrically couple and decouple a DC power source to and from, respectively, the rotor windings.

Abstract: A starter-generator includes redundant motor/generator sets disposed within a common housing. Each motor/generator set is electrically and mechanically independent of one another, with the exception of a common input/output gear. The starter-generator is configured such that if one of the motor/generator sets experiences a predetermined torsional load, it will decouple from the input/output gear, allowing the other motor/generator set to continue operation uninterrupted.

Abstract: A generator system is configured to supply relatively constant frequency AC power when driven by a variable speed prime mover, by independently controlling the main rotor flux rotational speed. The generator system includes an exciter stator that induces current in the exciter rotor windings at a desired frequency and phasing. The exciter rotor windings are electrically connected to the main rotor windings, and are thus electrically excited at the same frequency and phasing. Excitation is supplied to the exciter stator from an exciter controller, which controls the frequency and phasing of the exciter excitation, based on the rotational speed of the generator, to maintain a constant output frequency.

Abstract: A rotating electrical machine, such as an aircraft starter-generator, that may be operated in either a DC motor mode or an AC generator mode. The machine includes a conventionally wound main stator that is selectively configurable as a multi-pole AC stator and a multi-pole DC stator. The machine also includes rotor windings that are configured to be selectively coupled to either an exciter or a plurality of commutator segments, and DC brushes that are selectively moveable into, and out of, electrical contact with the commutator segments, to thereby electrically couple and decouple a DC power source to and from, respectively, the rotor windings.

Abstract: Methods and apparatus for retaining a butterfly plate within a valve housing after complete drive shaft failure. More particularly, the present invention is directed to the use of a pin extending between the butterfly plate and the valve housing where an end of the pin extends into a semi-circular channel centered on the center axis of the drive shaft. In preferred embodiments, the pin is immovably fixed to the valve housing, and extends into a channel on the butterfly plate assembly where the channel is sized, dimensioned, and positioned such that it corresponds to the path of an end of the pin as the plate rotates on the drive shaft.

Abstract: A rotating electrical machine, such as an aircraft starter-generator, that includes an exciter that has its stator windings supplied with electrical power from a power supply. One or more switches are electrically coupled between the exciter stator winding and the power supply and are configured and controlled so that a capacitance may be selectively placed electrically in series with the exciter stator windings.

Abstract: One embodiment of the invention relates to a low profile electric generator having a short axial length. A cylindrical rotor body defines an interior cavity and is coupled to a driveshaft along the axis of the cylindrical body. A first rotor assembly is coupled to the inner surface of the cylindrical body, the first rotor assembly defining a space to receive a first stator that is independent from the cylindrical body. A second rotor assembly is coupled to the outer surface of the cylindrical body and electrically coupled to the first rotor assembly. A second stator is arranged around the second rotor assembly, independent from the cylindrical body, and radially positioned about the axis of the cylindrical body. By arranging the generator components in such configuration, the axial length of the generator is reduced in comparison to a conventional generator.