Abstract:
A nearly 2 to 1 boosting mufti-phase AC-to-DC converter may include a main rectifier, an auxiliary rectifier; and an autotransformer connected to the main rectifier and the auxiliary rectifier. The autotransformer may include a plurality of interconnected windings arranged in a plurality of legs, with one of the legs for each phase and with each leg including a plurality of windings, wherein all but one of the windings of each leg have equal turns ratios and one of the windings of each leg has a turns ratio that is less than the turns ratio of all of the other windings of the respective leg.
Abstract:
Landing gear apparatus for an aircraft may include a steerable nosewheel assembly and left main landing gear wheels and right main landing gear wheels driven by motors. A controller may receive an angular position of the nosegear wheel assembly. The controller may respond to the angular position by transmitting wheel speed signals to one or more of the motors to maintain the center of gravity of the aircraft within a predetermined stability triangle and to perform short radii turning.
Abstract:
A composition is provided for converting and removing undesirable gases from air comprising manganese dioxide, titanium dioxide and an alkali.
Abstract:
A connection system for carrying a refrigerant may provide a hybrid redundancy in sealing a refrigerant flow from the surround system environment. The connection system may include a first sealing ring of a first type and a second sealing ring of a second type positioned downstream from the first sealing ring. In some embodiments, the first sealing ring may be in a groove positioned around the outside diameter of a male fitting. The second sealing ring may be positioned at an interface between the male fitting and a female fitting. In some embodiments, flanges of each fitting define the interface so that the second sealing ring may be positioned between the flanges of each fitting. The second sealing ring may be selected from a material that has a wider range of operating temperature than the first sealing ring so that in the event of failure in the first sealing ring, the second sealing ring may prevent leakage.
Abstract:
A journal foil bearing includes a bearing retainer having one slot configured to receive a top foil leading edge tab and another slot configured to receive a top foil trailing edge tab. A backup support structure, integral to the bearing retainer, extends between and is at least partially defined by the slots. The retainer is configured so that, during operation, the trailing edge tab contacts the support structure at a position close to the friction force, thereby minimizing top foil bending stress and improving bearing strength.
Abstract:
An electric drive system may include a plurality of heat sensitive components, at least one temperature sensor positioned in or on each of the components and a system controller. The temperature sensors may be interconnected with the system controller to transmit temperature data from their respective heat sensitive components to the system controller. The system controller may be configured to transmit a reduced performance command in the event that a reached-temperature-threshold-limit signal is received from any one or more of the temperature sensors. System shutdown due to over temperature faults may be avoided.
Abstract:
A motor cooling system is provided comprising an electric motor including a rotor having first and second axial ends, and a stator having first and second axial ends, a motor housing surrounding the motor including an air chamber extending around the motor and axially along the motor length, a motor enclosure enveloping the motor housing, and a cooling fan radially mounted to the motor enclosure and adapted to operatively cool said electric motor.
Abstract:
An electric drive system may include a plurality of heat sensitive components, at least one temperature sensor positioned in or on each of the components and a system controller. The temperature sensors may be interconnected with the system controller to transmit temperature data from their respective heat sensitive components to the system controller. The system controller may be configured to transmit a reduced performance command in the event that a reached-temperature-threshold-limit signal is received from any one or more of the temperature sensors. System shutdown due to over temperature faults may be avoided.
Abstract:
A microgrid system may control power distribution among a plurality of interconnected microgrids operated under droop mode. The microgrids may operate both autonomously and as part of the system. Stable power distribution between the microgrids may be performed by monitoring operation of the microgrids and electrically disconnecting the microgrids from one another when a power outage or performance outside of a tolerance is detected. Network lines between the microgrids may remain in communication while the microgrids are disconnected from one another. The microgrids may operate autonomously under a preset operating droop frequency until power stability is detected at a boundary between adjacent microgrids. The microgrids may communicate with one another adjusting operating droop until synchronization among microgrids is achieved and the microgrids can be reconnected into the microgrid system.
Abstract:
A microgrid system may control power distribution among a plurality of interconnected microgrids operated under droop mode. The microgrids may operate both autonomously and as part of the system. Stable power distribution between the microgrids may be performed by monitoring operation of the microgrids and electrically disconnecting the microgrids from one another when a power outage or performance outside of a tolerance is detected. Network lines between the microgrids may remain in communication while the microgrids are disconnected from one another. The microgrids may operate autonomously under a preset operating droop frequency until power stability is detected at a boundary between adjacent microgrids. The microgrids may communicate with one another adjusting operating droop until synchronization among microgrids is achieved and the microgrids can be reconnected into the microgrid system.