Abstract: A generator system is configured to supply two phase excitation current from an exciter rotor to a main generator rotor. When driven by a variable speed prime mover, the generator system provides relatively constant frequency AC power 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 to provide two-phase excitation current to the main rotor windings. 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: An aircraft architecture may be designed to create an optimal balance between electric power and bleed power in order to match or improve current more electric architecture (MEA) performance while simplifying power extraction from the engines as well as simplifying the electrical system. Conventional aircraft architectures may use electric only ECS and cabin pressurization systems (so-called “no bleed” systems). Alternatively, older conventional aircraft may use strictly engine bleed air to provide power for ECS and cabin pressurization systems. The present invention, on the other hand, provides an architecture which may optimize the use of both engine bleed air and MEA designs to provide a system that may be simpler and potentially more reliable and available as compared to conventional aircraft architectures.

Abstract: A power generation and distribution system utilizes two or more AC generators each of which may be driven by a separate prime mover such as a turbine. The generators may be driven at different rotational speeds. AC power from the generators may be rectified and applied to a common DC bus. Electrical loads may be applied to the common bus and may establish an electrical power requirement. Allocation of electrical power requirement may be made among the generators based on power available from the turbines.

Abstract: A generator system is configured to supply two phase excitation current from an exciter rotor to a main generator rotor. When driven by a variable speed prime mover, the generator system provides relatively constant frequency AC power 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 to provide two-phase excitation current to the main rotor windings. 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 generator system is configured to supply two phase excitation current from an exciter rotor to a main generator rotor. When driven by a variable speed prime mover, the generator system provides relatively constant frequency AC power 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 to provide two-phase excitation current to the main rotor windings. 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 stub shaft of a main rotor shaft of a generator has its flange or shoulder removed from its outer portion so in the event of a bending failure of the stub shaft the resulting axial load of the stub shaft is not transmitted to the main rotor shaft. Instead of a retention plug adjacent the distal end of the inside portion of the stub shaft, a knock out plug is lightly press-fit into the main rotor shaft. In the event of a failure, the outside portion of the stub shaft enters the main rotor shaft without applying an axial load onto the main rotor shaft, moves axially and displaces the knock-out plug without exiting the main rotor shaft.

Abstract: An aircraft architecture may be designed to create an optimal balance between electric power and bleed power in order to match or improve current more electric architecture (MEA) performance while simplifying power extraction from the engines as well as simplifying the electrical system. Conventional aircraft architectures may use electric only ECS and cabin pressurization systems (so-called “no bleed” systems). Alternatively, older conventional aircraft may use strictly engine bleed air to provide power for ECS and cabin pressurization systems. The present invention, on the other hand, provides an architecture which may optimize the use of both engine bleed air and MEA designs to provide a system that may be simpler and potentially more reliable and available as compared to conventional aircraft architectures.

Abstract: A method and apparatuses are used for power conversion. The apparatus according to one embodiment comprises a plurality of power conversion modules (130—1, . . . , 130—n), the plurality of power conversion modules (130—1, . . . , 130—n) being optionally controllable to function independently of each other to supply a plurality of systems (200—1, . . . , 200—n), function in an inter-relational mode in which at least one power conversion module from the plurality of power conversion modules (130—1, . . . , 130—n) drives a system and, upon a failure of the at least one power conversion module, at least another power conversion module from the plurality of power conversion modules (130—1, . . . , 130—n) will drive the system, and function in a scalable mode in which at least two power conversion modules of the plurality of power conversion modules (130—1, . . . , 130—n) are connected to provide an additive output.

Abstract: A method and apparatuses are implemented for electric power systems. An apparatus for power conversion according to one embodiment comprises: a multiple function power converter (77), the multiple function power converter (77) being capable of performing functions of a static inverter, and being capable of at least one of performing functions of a motor controller, and performing functions of a start converter to use a generator as a starter. An architecture system for aircraft according to another embodiment comprises: one or more rectifiers (408), wherein the one or more rectifiers (408) receive at least one high frequency AC power input; and a plurality of power conversion devices (78) optionally connectable to drive at least one high frequency generator (105) as a starter and at least one load, the input of each power conversion device (78) being connected to at least one rectifier (408).

Abstract: An axial impact liner comprises a bearing liner having a shear member and a pocket. A spring and a supply of oil may be included within the pocket. In the event of an axial load, such as from a bearing or main rotor failure, the axial impact liner can shear in the axial direction and absorb the energy of the axial load by forcing the shear member into the oil filled pocket and against the spring. The pocket comprises a volume capable of accommodating the full axial distance that the rotor could move.

Abstract: A rotor resistor and switch combination may cause a starter/generator device to function as an asynchronous device when in a start mode. Thus, starting torque may result. A starter/generator device may include an exciter rotor winding, a main rotor winding, and a resistor and switch combination positioned between the exciter rotor winding and the main rotor winding to control a flow of current in the main rotor winding during a start mode of the starter/generator device. A method of optimizing starting torque of a starter/generator device without a start controller unit during a start mode may include providing a main rotor winding of the starter/generator device, and providing a control to control a flow of current in the main rotor winding during the start mode.

Abstract: A power generation and distribution system utilizes two or more AC generators each of which may be driven by a separate prime mover such as a turbine. The generators may be driven at different rotational speeds. AC power from the generators may be rectified and applied to a common DC bus. Electrical loads may be applied to the common bus and may establish an electrical power requirement. Allocation of electrical power requirement may be made among the generators based on power available from 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 main stator that is selectively configurable as a multi-pole AC stator and a multi-pole DC stator. The machine also includes DC brushes that are selectively moveable into, and out of, electrical contact the main rotor, to thereby electrically couple and decouple a DC power source to and from, respectively, the rotor windings.

Abstract: An electric machine includes a fluid control system that is configured to regulate the flow rate of fluid to the electric machine. The machine includes a sensor that senses a parameter representative of cooling required by the machine. The sensor supplies a sensor signal to a control unit, which in turn supplies a flow control signal to a flow regulator. The flow regulator, in response to the flow control signal, controls the flow rate of fluid to the machine to what is needed for effective cooling at current operating conditions. As a result, windage losses and pumping power requirements in the machine are reduced, and machine efficiency is increased.

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 stub shaft of a main rotor shaft of a generator has its flange or shoulder removed from its outer portion so in the event of a bending failure of the stub shaft the resulting axial load of the stub shaft is not transmitted to the main rotor shaft. Instead of a retention plug adjacent the distal end of the inside portion of the stub shaft, a knock out plug is lightly press-fit into the main rotor shaft. In the event of a failure, the outside portion of the stub shaft enters the main rotor shaft without applying an axial load onto the main rotor shaft, moves axially and displaces the knock-out plug without exiting the main rotor shaft.

Abstract: An axial impact liner comprises a bearing liner having a shear member and a pocket. A spring and a supply of oil may be included within the pocket. In the event of an axial load, such as from a bearing or main rotor failure, the axial impact liner can shear in the axial direction and absorb the energy of the axial load by forcing the shear member into the oil filled pocket and against the spring. The pocket comprises a volume capable of accommodating the full axial distance that the rotor could move.

Abstract: A starter-generator system may be used to supply sufficient starting torque to start an aircraft main engine. The main starter-generator stator winding may be connected to a constant frequency (CF) power source to create a rotating field in the main starter-generator air gap. This rotating field, in turn, may induce current on the main rotor winding, which may be a closed circuit formed by main rotor field winding and exciter armature winding. The interaction between the main rotor current and the air gap flux may give rise to the starting torque to start the main engine. Adjusting the voltage supplied to the exciter stator field winding can modify the induced voltage and current on the rotor circuit to control the rotor current and starting torque. The starter-generator system may also be used to start an aircraft main engine by directly connecting the main stator winding to a power source without powering the exciter stator.

Abstract: A rotor resistor and switch combination may cause a starter/generator device to function as an asynchronous device when in a start mode. Thus, starting torque may result. A starter/generator device may include an exciter rotor winding, a main rotor winding, and a resistor and switch combination positioned between the exciter rotor winding and the main rotor winding to control a flow of current in the main rotor winding during a start mode of the starter/generator device. A method of optimizing starting torque of a starter/generator device without a start controller unit during a start mode may include providing a main rotor winding of the starter/generator device, and providing a control to control a flow of current in the main rotor winding during the start mode.

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.