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 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 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 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 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: 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.

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 may be operated in either a motor mode or an generator mode. The machine includes a main rotor that is selectively configurable as an M-pole rotor or an N-pole rotor. The machine can also include 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: 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: 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: A rotating electrical machine, such as an aircraft starter-generator, includes an exciter that has its stator windings divided into a number of sections. A plurality of switches are electrically coupled to the exciter stator winding sections and are configured and controlled so that the exciter stator winding sections may be selectively coupled in series or in parallel with one another, and selectively coupled to receive either DC or AC power.

Abstract: A high speed generator has its main rotor located within the main generator shaft assembly. The main rotor is mounted on a substantially hollow rotor shaft, which is also mounted within the main generator shaft assembly. The main stator surrounds at least a portion of the main generator shaft assembly. Main rotor cooling supply orifices extend through the rotor shaft. Main stator cooling supply orifices, which are in fluid communication with the main rotor cooling supply orifices, extend through the main generator shaft assembly. Cooling fluid is directed into the main generator shaft assembly, and flows through the main rotor cooling supply orifices and the main stator cooling supply orifices. The main rotor and main stator cooling supply orifices are configured to supply the main rotor and main stator with a cooling fluid spray. This configuration reduces the rotational fluid mass associated with flood-cooled rotors, which increases structural integrity, lowers material stresses, improves rotor dynamics.

Abstract: A rotating electrical machine, such as an aircraft starter-generator, that may be operated in either a motor mode or an generator mode. The machine includes a main rotor that is selectively configurable as an M-pole rotor or an N-pole rotor. The machine can also include 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: 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: A rotating electrical machine, such as an aircraft starter-generator, includes an exciter that has its stator windings divided into a number of sections. A plurality of switches are electrically coupled to the exciter stator winding sections and are configured and controlled so that the exciter stator winding sections may be selectively coupled in series or in parallel with one another, and selectively coupled to receive either DC or AC power.

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: A high speed generator has its main rotor located within the main generator shaft assembly. The main rotor is mounted on a substantially hollow rotor shaft, which is also mounted within the main generator shaft assembly. The main stator surrounds at least a portion of the main generator shaft assembly. Main rotor cooling supply orifices extend through the rotor shaft. Main stator cooling supply orifices, which are in fluid communication with the main rotor cooling supply orifices, extend through the main generator shaft assembly. Cooling fluid is directed into the main generator shaft assembly, and flows through the main rotor cooling supply orifices and the main stator cooling supply orifices. The main rotor and main stator cooling supply orifices are configured to supply the main rotor and main stator with a cooling fluid spray. This configuration reduces the rotational fluid mass associated with flood-cooled rotors, which increases structural integrity, lowers material stresses, improves rotor dynamics.

Abstract: A rotating electrical machine, such as an aircraft starter-generator, includes an exciter that has its stator windings divided into a number of sections. A plurality of switches are electrically coupled to the exciter stator winding sections and are configured and controlled so that the exciter stator winding sections may be selectively coupled in series or in parallel with one another, and selectively coupled to receive either DC or AC power.