Abstract: A seal ring assembly for a rotor shaft includes a seal casing defining a radially inwardly directed channel. The seal ring is disposed in the radially inwardly directed channel of the seal casing. The seal ring is resiliently joined about the shaft to form a seal, and the seal ring comprises an electrically insulating or dissipative material or a non-metallic material.

Abstract: Various embodiments include a system having: at least one computing device configured to monitor a dynamoelectric machine having a rotor including an exciter electrically coupled with a field winding, by performing actions including: obtaining measured data indicating a resistance of the field winding at a plurality of rotor angular positions while the rotor is rotating at a speed below one-hundred revolutions per minute; comparing the measured data indicating the resistance of the field winding at the plurality of rotor angular positions with a threshold resistance range; and indicating a potential fault in the field winding in response to determining the measured data indicating the resistance deviates from the threshold resistance range.

Abstract: A retention assembly for retaining a plurality of elements in a stator slot of an electric machine is provided. The retention assembly may include a stator wedge fixedly positioned in a dovetail in the stator slot to retain the plurality of elements; a top ripple spring between the plurality of elements and the stator wedge; and at least one shim positioned between the stator wedge and a load bearing surface of the dovetail. A method may include compressing the stator wedge in the stator slot from a first position thereof relative to the dovetail of the stator slot, the compressing creating a gap between the stator wedge and the dovetail. A shim may be inserted in the gap; the compressing released such that the shim retains the stator wedge in a second position that is more compressed relative to the plurality of elements in the stator slot compared to the first position.

Abstract: Various embodiments include a system having: at least one computing device configured to monitor a dynamoelectric machine having a rotor including an exciter electrically coupled with a field winding, by performing actions including: obtaining measured data indicating a resistance of the field winding at a plurality of rotor angular positions while the rotor is rotating at a speed below one-hundred revolutions per minute; comparing the measured data indicating the resistance of the field winding at the plurality of rotor angular positions with a threshold resistance range; and indicating a potential fault in the field winding in response to determining the measured data indicating the resistance deviates from the threshold resistance range.

Abstract: A seal ring assembly for a rotor shaft includes a seal casing defining a radially inwardly directed channel. The seal ring is disposed in the radially inwardly directed channel of the seal casing. The seal ring is resiliently joined about the shaft to form a seal, and the seal ring comprises an electrically insulating or dissipative material or a non-metallic material.

Abstract: A system for detecting a gas leak in a generator includes a source of carbon dioxide gas, and a subsystem for introducing the carbon dioxide gas into the generator. An infrared imaging device is adapted to communicate with a notification device to display an image of at least a portion of the generator and the carbon dioxide gas. The infrared imaging device is a cooled detector and a filter with a spectral response between about 3 ?m and about 5 ?m. At least one of the detector and the filter is cooled to between about ?80° C. and about ?200° C. The gas leak will be indicated on the notification device.

Abstract: A system for detecting a gas leak in a machine includes a source of a non-corrosive tracer gas, and a subsystem for introducing the non-corrosive tracer gas into the machine. An infrared imaging device is adapted to communicate with a notification device to display an image of at least a portion of the machine. The infrared imaging device has a cooled detector and a filter with a spectral response between about 3 ?m and about 5 ?m. At least one of the detector and the filter is cooled. The infrared imaging device includes one of a mercury cadmium telluride (MCT) photodetector, an indium antimonide (InSb) photodetector or a mid-wavelength quantum well infrared photodetector (QWIP). The notification device is adapted to indicate the gas leak.

Abstract: A system for detecting a gas leak in a generator includes a source of carbon dioxide gas, and a subsystem for introducing the carbon dioxide gas into the generator. An infrared imaging device is adapted to communicate with a notification device to display an image of at least a portion of the generator and the carbon dioxide gas. The infrared imaging device is a cooled detector and a filter with a spectral response between about 3 ?m and about 5 ?m. At least one of the detector and the filter is cooled to between about ?80° C. and about ?200° C. The gas leak will be indicated on the notification device.

Abstract: A retention assembly for retaining a plurality of elements in a stator slot of an electric machine is provided. The retention assembly may include a stator wedge fixedly positioned in a dovetail in the stator slot to retain the plurality of elements; a top ripple spring between the plurality of elements and the stator wedge; and at least one shim positioned between the stator wedge and a load bearing surface of the dovetail. A method may include compressing the stator wedge in the stator slot from a first position thereof relative to the dovetail of the stator slot, the compressing creating a gap between the stator wedge and the dovetail. A shim may be inserted in the gap; the compressing released such that the shim retains the stator wedge in a second position that is more compressed relative to the plurality of elements in the stator slot compared to the first position.

Abstract: Various embodiments include apparatuses adapted to include a dynamoelectric machine rotor with a modified outer surface. In some embodiments apparatuses include a dynamoelectric machine rotor including a rotor body having a spindle, pole regions, the pole regions having a non-uniform radial distance from an axis of rotation of the rotor to an outer surface of the pole regions and a plurality of slots in the outer surface of the rotor body, the plurality of slots being spaced apart in a circumferential direction of the rotor body, each of the plurality of slots extending in an axial direction of the rotor body.

Abstract: A system and method for detecting a gas leak in a generator is provided. The system includes a source of a non-corrosive tracer gas, and a subsystem for introducing the non-corrosive tracer gas into the hydrogen cooled generator. An infrared imaging device is adapted to communicate with a notification device to display an image of at least a portion of the hydrogen cooled generator and the non-corrosive tracer gas. The infrared imaging device includes a cooled detector, and a filter with a spectral response between about 3 ?m and about 5 ?m. The detector and/or the filter is cooled to between about ?80° C. and about ?200° C. The gas leak will be indicated on the notification device. The generator may hydrogen cooled, and on-line or on-grid.

Abstract: A system and method for detecting a gas leak in a generator is provided. The system includes a source of a non-corrosive tracer gas, and a subsystem for introducing the non-corrosive tracer gas into the hydrogen cooled generator. An infrared imaging device is adapted to communicate with a notification device to display an image of at least a portion of the hydrogen cooled generator and the non-corrosive tracer gas. The infrared imaging device includes a cooled detector, and a filter with a spectral response between about 3 ?m and about 5 ?m. The detector and/or the filter is cooled to between about ?80° C. and about ?200° C. The gas leak will be indicated on the notification device. The generator may hydrogen cooled, and on-line or on-grid.

Abstract: Various embodiments include apparatuses adapted to include a dynamoelectric machine rotor with a modified outer surface. In some embodiments apparatuses include a dynamoelectric machine rotor including a rotor body having a spindle, pole regions, the pole regions having a non-uniform radial distance from an axis of rotation of the rotor to an outer surface of the pole regions and a plurality of slots in the outer surface of the rotor body, the plurality of slots being spaced apart in a circumferential direction of the rotor body, each of the plurality of slots extending in an axial direction of the rotor body.

Abstract: An approach for cooling a stator core flange is provided. In one aspect, a pair of stator flanges each disposed at opposing ends of a stator core assembly maintains a compressive load on the stator core assembly. Heat transport tubes may be located about at least one of the stator flanges at an end of the stator core assembly to redistribute heat therefrom.

Abstract: An approach for cooling a stator core flange is provided. In one aspect, a pair of stator flanges each disposed at opposing ends of a stator core assembly maintains a compressive load on the stator core assembly. Heat transport tubes may be located about at least one of the stator flanges at an end of the stator core assembly to redistribute heat therefrom.

Abstract: Embodiments of the invention relate generally to lead path configurations in generator rotors and, more particularly, to a support apparatus for a main lead and generator rotors incorporating such a support apparatus. In one embodiment, the invention provides a generator rotor comprising: a rotor shaft including an internal conductive bore; a main terminal electrically connected to the conductive bore; a plurality of rotor coil windings, including a plurality of coil end straps; a non-metallic support channel comprising: an elongate, axially-oriented channel; and at least one protrusion extending from the elongate, axially-oriented channel to a position between two of the plurality of coil end straps; and a main lead extending from the main terminal, through the elongate, axially-oriented channel of the non-metallic support channel, to at least one of the plurality of coil end straps.

Abstract: Embodiments of the invention relate generally to lead path configurations in generator rotors and, more particularly, to a support apparatus for a main lead and generator rotors incorporating such a support apparatus. In one embodiment, the invention provides a generator rotor comprising: a rotor shaft including an internal conductive bore; a main terminal electrically connected to the conductive bore; a plurality of rotor coil windings, including a plurality of coil end straps; a non-metallic support channel comprising: an elongate, axially-oriented channel; and at least one protrusion extending from the elongate, axially-oriented channel to a position between two of the plurality of coil end straps; and a main lead extending from the main terminal, through the elongate, axially-oriented channel of the non-metallic support channel, to at least one of the plurality of coil end straps.

Abstract: Embodiments of the invention relate generally to lead path configurations in generator rotors and, more particularly, to a support apparatus for a main lead and generator rotors incorporating such a support apparatus. In one embodiment, the invention provides a support apparatus for a main lead of a generator rotor, the support apparatus comprising: a cross-sectionally L-shaped body having: a first portion; and a second portion substantially perpendicular to the first portion, wherein the first portion includes an arcuate first surface for interfacing with a centering ring of the generator rotor and an arcuate second surface adapted to be substantially parallel to a rotor shaft of the generator rotor; a main lead passage extending along the arcuate first surface of the first portion and through the second portion.

Abstract: Embodiments of the invention relate generally to lead path configurations in generator rotors and, more particularly, to a support apparatus for a main lead and generator rotors incorporating such a support apparatus. In one embodiment, the invention provides a support apparatus for a main lead of a generator rotor, the support apparatus comprising: a cross-sectionally L-shaped body having: a first portion; and a second portion substantially perpendicular to the first portion, wherein the first portion includes an arcuate first surface for interfacing with a centering ring of the generator rotor and an arcuate second surface adapted to be substantially parallel to a rotor shaft of the generator rotor; a main lead passage extending along the arcuate first surface of the first portion and through the second portion.

Abstract: An electrical machine includes a stator having a radically inwardly directed duct adjacent the center of the machine for flowing cooling medium into the gap between the stator and rotor. The rotor includes radial or diagonal ducts having scoops for directing flow generally radically inwardly to cool the field windings in the center of the machine. The cooling medium flows either into subslots for radial or diagonal outward flow through outlet ducts for return to the gap.