Abstract: A high speed generator cooling system directs a cooling oil spray through a chamber inside a coil support wedge assembly, which may be disposed adjacent to the generator coils. Heat from the generator coils may be conducted through the walls of the coil support wedge assembly and into the chamber where it is removed by the cooling oil spray passing through the chamber. The cooling oil passes through a generator rotor shaft and into a cooling passage in least one of the rotor laminations.

Abstract: A rotor mount assembly for an electrical machine, such as a high speed aerospace generator, comprises a spring having a simple annular structure together with an oil squeeze film damper (SFD). The spring is engineered to move the rotor critical speeds outside of the extremes of the operating speed range and the SFD damps out the rotor responses as the speed passes through these points.

Abstract: A method for manufacturing a rotor shaft is provided. A rod is formed from a metal matrix composite material, the rod having an outer diameter. The rod is heated to attain a stiffness thereof that is greater than about 300 GPa. A machinable sleeve is formed from material having a stiffness that is less than the stiffness of the rod and that is different than the material of the rod, the sleeve having an inner diameter that is equal to or less than the rod outer diameter. The rod is inserted into the sleeve, after the rod is heated.

Abstract: Centering rings may be used to modify the combined resonance of a rotor and its support assembly to migrate the rotor critical speeds such that they can be engineered out of the rotor operating speed range. The centering rings of the present invention may be useful for any rotating electrical machinery, especially high speed aerospace applications, such as generators and starter-generators.

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 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 high speed generator cooling system directs a cooling oil spray through a chamber inside a coil support wedge assembly, which may be disposed adjacent to the generator coils. Heat from the generator coils may be conducted through the walls of the coil support wedge assembly and into the chamber where it is removed by the cooling oil spray passing through the chamber. The cooling oil passes through a generator rotor shaft and into a cooling passage in least one of the rotor laminations.

Abstract: A rotor mount assembly for an electrical machine, such as a high speed aerospace generator, comprises a spring having a simple annular structure together with an oil squeeze film damper (SFD). The spring is engineered to move the rotor critical speeds outside of the extremes of the operating speed range and the SFD damps out the rotor responses as the speed passes through these points.

Abstract: Centering rings may be used to modify the combined resonance of a rotor and its support assembly to migrate the rotor critical speeds such that they can be engineered out of the rotor operating speed range. The centering rings of the present invention may be useful for any rotating electrical machinery, especially high speed aerospace applications, such as generators and starter-generators.

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 rotor balancing system is provided that includes a rotor core, a plurality of core channels, a support wedge, a wedge channel, and balance masses. The rotor core includes an annular section, a first pole, and a second pole. The first and second poles each extend radially outwardly from the annular section and form an interpole region therebetween. The plurality of core channels are formed in the rotor core annular section and extend axially through the rotor core annular section. The support wedge is disposed in the interpole region. The wedge channel is formed in the support wedge and extends therethrough. One or more balance masses are selectively disposed in one or more of the core channels and the wedge channel, and each balance mass is disposed at a predetermined axial location to thereby correct rotor imbalance.

Abstract: A coil retention system for a rotor of a high speed electrical generator, such as an aircraft generator, that uses compliant material to fill variable dimension voids and/or gaps in the coils wound around the rotor of an electrical machine. During processing of the rotor and coil retention system, the compliant material hardens and is able to withstand the centrifugal loads imposed by, and environmental conditions within, the high speed generator.

Abstract: A coil retention system for a rotor of an electrical generator, such as an aircraft generator, that includes one or more components made of a high strength, lightweight composite material. By making one or more of the coil retention system components of a high strength, lightweight composite material, the generator can rotate at relatively high speeds, and can be built with a relatively small space between the generator rotor and stator. This allows the generator to supply greater output power without increasing the generator's size and/or weight.

Abstract: A coil support wedge for a high speed generator is integrally constructed and includes a plurality of flow passageways. Because it is integrally formed, the support wedge is substantially fluid tight. Thus, it is less susceptible to cooling fluid leakage from the flow passageways, which increases the overall reliability of the generator into which the wedge is installed.

Abstract: A coil retention system for a rotor of a high speed electrical generator, such as an aircraft generator, that uses compliant material to fill variable dimension voids and/or gaps in the coils wound around the rotor of an electrical machine. During processing of the rotor and coil retention system, the compliant material hardens and is able to withstand the centrifugal loads imposed by, and environmental conditions within, the high speed generator.