Abstract: A fault tolerant synchronous permanent magnet machine is disclosed that reduces rotor losses by limiting eddy-current losses in the retaining sleeve. The machine limits eddy-current loss by any one or combination of axially segmenting the retaining sleeve, providing a highly electrically conductive non-magnetic shield to the retaining sleeve, and by configuring stator teeth width, stator teeth tip width, and slot distribution of the stator.

Abstract: An electrical machine includes a stator and a rotor. The stator has a central opening that is configured to receive the rotor. The rotor includes a generally cylindrical first section comprising a first material mounted on an axially extending shaft within the central opening. The rotor further includes a second section having a second material of a predetermined thickness that is plated integrally over at least a portion of the first section. The second material has a higher electrical conductivity relative to the first material.

Abstract: An electrical machine includes a stator and a rotor. The stator has a central opening that is configured to receive the rotor. The rotor includes a generally cylindrical first section comprising a first material mounted on an axially extending shaft within the central opening. The rotor further includes a second section having a second material of a predetermined thickness that is plated integrally over at least a portion of the first section. The second material has a higher electrical conductivity relative to the first material. In certain embodiments, the electrical machine may include a stator support structure having a clamping member comprising a first material and configured to rigidly position the stator around the rotor. The stator support structure further includes an electrically conductive layer comprising a second material plated integrally over the clamping structure, wherein the second material has a higher electrical conductivity relative to the first material.

Abstract: A PM machine is provided. The PM machine includes a stator including a stator core, wherein the stator core defines multiple step-shaped stator slots. The stator includes multiple fractional-slot concentrated windings wound within the step-shaped stator slots. The stator also includes at least one slot wedge configured to close an opening of a respective one of the step-shaped stator slots, wherein the slot wedge is further configured to adjust the leakage inductance in the PM machine. The PM machine also includes a rotor having a rotor core and disposed outside and concentric with the stator, wherein the rotor core includes a laminated back iron structure disposed around multiple axially-segmented magnets.

Abstract: A PM machine is provided. The PM machine includes a stator including a stator core, wherein the stator core defines multiple step-shaped stator slots. The stator includes multiple fractional-slot concentrated windings wound within the step-shaped stator slots. The stator also includes at least one cooling tube disposed around the windings. The stator further includes a first insulation layer disposed around the cooling tube. The stator also includes a second insulation layer disposed around the first insulation layer. The stator further includes at least one slot wedge configured to close an opening of a respective one of the step-shaped stator slots, wherein the slot wedge is further configured to adjust a leakage inductance in the PM machine. The PM machine also includes a rotor having a rotor core and disposed outside and concentric with the stator, wherein the rotor core includes a laminated back iron structure disposed around multiple magnets.

Abstract: A synchronous reluctance machine is provided. The synchronous reluctance machine includes a stator having a stator core, the stator core including a number of fractional-slot concentrated windings wound around multiple stator teeth. The synchronous reluctance machine also includes a rotor having a rotor core and disposed with an air gap inside and concentric with the stator, wherein the rotor core includes a number of laminated sheets, wherein each of the laminated sheets is axially skewed with respect to neighboring ones of the laminated sheets, and wherein each of the laminated sheets includes multiple ferromagnetic regions and multiple non-ferromagnetic regions formed of a single material.

Abstract: A permanent magnet (PM) machine includes a plurality of reconfigurable fault condition mechanisms disposed within a stator core portion, the plurality of reconfigurable fault condition mechanisms together automatically reconfigurable to reduce fault currents and internal heat associated with the PM machine during a fault condition. The plurality of reconfigurable fault condition mechanisms are disposed solely within the stator core portion according to one embodiment to automatically reduce stator winding fault currents and internal heat associated with the PM machine during a fault condition.

Abstract: A permanent magnet (PM) machine has a reconfigurable fault condition mechanism disposed solely within a stator core portion, wherein the mechanism is automatically reconfigurable to reduce fault currents associated with the PM machine during a fault condition. The reconfigurable fault condition mechanism is automatically reconfigurable to also reduce internal heat associated with the PM machine during a fault condition. A method of reconfiguring the fault condition mechanism upon detection of a fault condition includes the steps of 1) selecting the reconfigurable fault condition mechanism from a) a plurality of rotatable magnetically anisotropic cylinders disposed within stator core slots, b) a plurality of ferrofluid-fillable cavities associated with stator core slots, and c) a sliding shield within the stator core; and 2) reconfiguring the fault condition mechanism to automatically reduce fault currents associated with the PM machine upon detection of a fault condition.

Abstract: A permanent magnet (PM) machine has a fault condition mechanism disposed within a back iron of the stator portion, the mechanism operational to automatically reduce fault currents associated with the PM machine during a fault condition. The fault condition mechanism disposed within the stator back iron is reconfigurable to automatically reduce internal heat associated with the PM machine during a fault condition. A method of reconfiguring the PM machine upon detecting a fault condition includes the steps of 1) selecting the reconfigurable fault condition mechanism from a) a plurality of magnetically anisotropic rotatable cylinders, b) a plurality of ferrofluid-filled cavities, and c) a dual-phase material selectively embedded within the stator core; and 2) reconfiguring the fault condition mechanism to automatically reduce fault currents or internal heat associated with the PM machine upon detection of a fault condition.

Abstract: A synchronous reluctance machine that has a stator and a rotor shaft operationally disposed within the confines of the stator. Laminations are axially stacked to form boat shaped segments. A plurality of selected boat shaped segments form a selected number of rotor poles about the rotor shaft and a plurality of support bars disposed intermittently between the boat shaped segments. Each segment of lamination is boat shaped with angular acuity facing towards the stator.

Abstract: An aspect of the invention is directed to a variable sensor head for use in multiple electric machines with varying slot openings comprising a ferromagnetic core; a first adjustable portion and a second adjustable portion positioned in communication with the ferromagnetic core wherein the first adjustable portion and the second adjustable portion are adjusted to fit between a plurality of slot openings of varying widths between a pair of lamination teeth of an electric machine. According to another embodiment, the first and second adjustable portions are sliding portions where the sliding portions may be spring biased to provide a close fit between the pair of lamination teeth. According to another embodiment, the first and second adjustable portions are adjustable screws.

Abstract: A synchronous reluctance machine is provided. The synchronous reluctance machine includes a stator having a stator core, the stator core including a number of fractional-slot concentrated windings wound around multiple stator teeth. The synchronous reluctance machine also includes a rotor having a rotor core and disposed with an air gap inside and concentric with the stator, wherein the rotor core includes a number of laminated sheets, wherein each of the laminated sheets is axially skewed with respect to neighboring ones of the laminated sheets, and wherein each of the laminated sheets includes multiple ferromagnetic regions and multiple non-ferromagnetic regions formed of a single material.

Abstract: A permanent magnet (PM) machine has a reconfigurable fault condition mechanism disposed solely within a stator core portion, wherein the mechanism is automatically reconfigurable to reduce fault currents associated with the PM machine during a fault condition. The reconfigurable fault condition mechanism is automatically reconfigurable to also reduce internal heat associated with the PM machine during a fault condition. A method of reconfiguring the fault condition mechanism upon detection of a fault condition includes the steps of 1) selecting the reconfigurable fault condition mechanism from a) a plurality of rotatable magnetically anisotropic cylinders disposed within stator core slots, b) a plurality of ferrofluid-fillable cavities associated with stator core slots, and c) a sliding shield within the stator core; and 2) reconfiguring the fault condition mechanism to automatically reduce fault currents associated with the PM machine upon detection of a fault condition.

Abstract: A permanent magnet (PM) machine has a fault condition mechanism disposed within a back iron of the stator portion, the mechanism operational to automatically reduce fault currents associated with the PM machine during a fault condition. The fault condition mechanism disposed within the stator back iron is reconfigurable to automatically reduce internal heat associated with the PM machine during a fault condition. A method of reconfiguring the PM machine upon detecting a fault condition includes the steps of 1) selecting the reconfigurable fault condition mechanism from a) a plurality of magnetically anisotropic rotatable cylinders, b) a plurality of ferrofluid-filled cavities, and c) a dual-phase material selectively embedded within the stator core; and 2) reconfiguring the fault condition mechanism to automatically reduce fault currents or internal heat associated with the PM machine upon detection of a fault condition.

Abstract: A permanent magnet (PM) machine includes a plurality of reconfigurable fault condition mechanisms disposed within a stator core portion, the plurality of reconfigurable fault condition mechanisms together automatically reconfigurable to reduce fault currents and internal heat associated with the PM machine during a fault condition. The plurality of reconfigurable fault condition mechanisms are disposed solely within the stator core portion according to one embodiment to automatically reduce stator winding fault currents and internal heat associated with the PM machine during a fault condition.

Abstract: A system is provided in a permanent magnet (PM) machine comprises a stator, a rotor configured to rotate relative to the stator, a first set of windings disposed within the stator; and a second set of windings wound back and forth toroidally around the circumference of the stator. In accordance with an embodiment of the present technique the set of windings is configured to generate a magnetic flux saturating the stator so as to limit fault currents within the PM machine.

Abstract: An electrical machine including a winding made of a conductive material is disclosed. The electrical machine also includes an insulating layer disposed around at least a portion of the winding having a dielectric constant that varies as a function of voltage.

Abstract: A fault tolerant synchronous permanent magnet machine is disclosed that reduces rotor losses by limiting eddy-current losses in the retaining sleeve. The machine limits eddy-current loss by any one or combination of axially segmenting the retaining sleeve, providing a highly electrically conductive non-magnetic shield to the retaining sleeve, and by configuring stator teeth width, stator teeth tip width, and slot distribution of the stator.

Abstract: A fault current limiter (FCL) comprises: an air core flat clock spiral inductor comprising wound electrically conductive material and insulated turns; and two terminations configured for attaching the spiral inductor in series with a power carrying conductor.

Abstract: Electric machines can be improved or uprated to reduce core-end losses using lower core loss material such as high grade iron silicon. A machine uprating entails removing at least a last one of the stacked lamination packages at each end of the stator core, and re-stacking the removed lamination packages with the lower core loss material.