Abstract: A method of fabricating a stator and a stator where the method includes providing a plurality of electromagnet cores, with each electromagnet core having a stack of laminations defining a tooth and a yoke segment. The yoke segment is defined by a stack of laminations having a tongue structure and an opposing groove structure. Representative methods also include providing an insulating bobbin surrounding a portion of the tooth of each lamination, such that each lamination is held against adjacent laminations by the bobbin. The method further includes the step of winding electrically conductive windings around a portion of the bobbin, and assembling the plurality of electromagnets into a stator by mating the tongue structure and the groove structure of each electromagnet with a corresponding tongue structure and a corresponding groove structure of adjacent electromagnets. Additional embodiments includes a stator having the above characteristics.

Abstract: An electric machine including a shaft, a rotor back assembly surrounding a portion of the shaft, and two or more permanent magnets radially positioned around the perimeter of the rotor back assembly. The electric machine also includes a rotor fan with multiple fan blades formed in an exterior surface of the rotor back assembly and one or more ventilation channels extending through the rotor back assembly. Methods of exporting heat from an electric machine, wither from a machine housing or through the shaft is also disclosed. The heat exportation methods feature the circulation of a fluid with the rotor fan through the ventilation channels and into contact with the housing, or exporting heat from the rotor back assembly through the shaft.

Abstract: An electric machine including a shaft, a rotor back assembly surrounding a portion of the shaft, and two or more permanent magnets radially positioned around the perimeter of the rotor back assembly. The electric machine also includes a rotor fan with multiple fan blades formed in an exterior surface of the rotor back assembly and one or more ventilation channels extending through the rotor back assembly. Methods of exporting heat from an electric machine, wither from a machine housing or through the shaft is also disclosed. The heat exportation methods feature the circulation of a fluid with the rotor fan through the ventilation channels and into contact with the housing, or exporting heat from the rotor back assembly through the shaft.

Abstract: An electric machine including a rotor shaft having an inner shaft core with a first composition and an outer shaft portion surrounding at least some of the inner shaft core. The outer shaft portion is fabricated from a material having a different composition than the inner shaft core. For example, the inner shaft core could be fabricated from a material having high thermal conductivity, such as copper, while the outer shaft portion is fabricated from a material with lesser thermal conductivity, but greater strength, for example steel. The two-material shaft with a highly thermally conductive core serves to conduct heat from the interior of the electric machine to the housing, or to an exterior apparatus or structure.

Abstract: An electric machine including a rotor shaft having an inner shaft core with a first composition and an outer shaft portion surrounding at least some of the inner shaft core. The outer shaft portion is fabricated from a material having a different composition than the inner shaft core. For example, the inner shaft core could be fabricated from a material having high thermal conductivity, such as copper, while the outer shaft portion is fabricated from a material with lesser thermal conductivity, but greater strength, for example steel. The two-material shaft with a highly thermally conductive core serves to conduct heat from the interior of the electric machine to the housing, or to an exterior apparatus or structure.

Abstract: An electric machine rotor including a shaft, a rotor back assembly surrounding a portion of the shaft, and a plurality of permanent magnets distributed at equal radial distance from the shaft around the rotor back assembly. The electric machine rotor also includes a gap between two adjacent permanent magnets and a thermally conductive material filing the gap. The thermally conductive material is in contact with the rotor back assembly between the two adjacent permanent magnets. The electric machine rotor also includes a heat transfer structure in thermal communication with the thermally conductive material, extending beyond an outer surface of the thermally conductive material to transfer heat away from the electric machine rotor.

Abstract: An electric machine rotor including a shaft, a rotor back assembly surrounding a portion of the shaft, and a plurality of permanent magnets distributed at equal radial distance from the shaft around the rotor back assembly. The electric machine rotor also includes a gap between two adjacent permanent magnets and a thermally conductive material filing the gap. The thermally conductive material is in contact with the rotor back assembly between the two adjacent permanent magnets. The electric machine rotor also includes a heat transfer structure in thermal communication with the thermally conductive material, extending beyond an outer surface of the thermally conductive material to transfer heat away from the electric machine rotor.

Abstract: A stator for an electromagnetic machine having a plurality of electromagnets. Some or all of the electromagnets include a stack of laminations defining a tooth and a yoke segment, and an insulating bobbin surrounding a portion of the tooth of each lamination such that each lamination is held against adjacent laminations by the bobbin. The electromagnets also include electrically conductive windings surrounding a portion of the bobbin and a stator encapsulant fully encapsulating the bobbin and windings of the electromagnets.

Abstract: An electromagnet for an electric machine having a stack of laminations defining a tooth and a yoke segment, and an insulating bobbin surrounding a portion of the tooth of each lamination, such that each lamination is held against adjacent laminations by the bobbin. The disclosed electromagnets also have electrically conductive windings surrounding a portion of the bobbin; and an encapsulant fully encapsulating the bobbin and windings, wherein the encapsulant comprises a dielectric material and an additive to increase the thermal conductivity of the encapsulant.

Abstract: An electric machine rotor including a shaft having a thermally conductive shaft core material having a different composition than a portion of the shaft surrounding the thermally conductive shaft core. The rotor also includes a rotor back assembly surrounding a portion of the shaft; and a plurality of permanent magnets radially positioned around the rotor back assembly.

Abstract: A stator for an electromagnetic machine having a plurality of electromagnets. Some or all of the electromagnets include a stack of laminations defining a tooth and a yoke segment, and an insulating bobbin surrounding a portion of the tooth of each lamination such that each lamination is held against adjacent laminations by the bobbin. The electromagnets also include electrically conductive windings surrounding a portion of the bobbin and a stator encapsulant fully encapsulating the bobbin and windings of the electromagnets.

Abstract: An electromagnet for an electric machine having a stack of laminations defining a tooth and a yoke segment, and an insulating bobbin surrounding a portion of the tooth of each lamination, such that each lamination is held against adjacent laminations by the bobbin. The disclosed electromagnets also have electrically conductive windings surrounding a portion of the bobbin; and an encapsulant fully encapsulating the bobbin and windings, wherein the encapsulant comprises a dielectric material and an additive to increase the thermal conductivity of the encapsulant.

Abstract: An electric machine having a rotor, stator and housing. The rotor includes a radially mounted array of permanent magnets and the stator includes a plurality of electromagnets radially positioned around the rotor. The machine includes a fluid circuit consisting of first and second cavities enclosed by the stator and positioned between the rotor and housing. The fluid circuit also includes an air gap between the stator and rotor and a plurality of ventilation channels extending through the rotor. The air gap and ventilation channels are in fluid communication with the first and second cavities. The rotor also includes an internal fan extending into the first or second cavity. When the rotor is caused to rotate with respect to the stator, the fan causes air or another fluid to circulate through the fluid circuit to cool the rotor.

Abstract: Methods and apparatus for enhancing the robustness and stability of an electric machine having a rotor, stator and housing. The rotor includes a radially mounted array of permanent magnets and the stator includes a plurality of electromagnets radially positioned around the rotor. The rotor is stabilized by providing a first thermally conductive dielectric encapsulant in contact with adjacent permanent magnets. The stator is stabilized by providing a second thermally conductive dielectric encapsulant in contact with adjacent electromagnets.

Abstract: An electric machine having a rotor, stator and housing. The rotor includes a radially mounted array of permanent magnets and the stator includes a plurality of electromagnets radially positioned around the rotor. The machine includes a fluid circuit consisting of first and second cavities enclosed by the stator and positioned between the rotor and housing. The fluid circuit also includes an air gap between the stator and rotor and a plurality of ventilation channels extending through the rotor. The air gap and ventilation channels are in fluid communication with the first and second cavities. The rotor also includes an internal fan extending into the first or second cavity. When the rotor is caused to rotate with respect to the stator, the fan causes air or another fluid to circulate through the fluid circuit to cool the rotor.

Abstract: Methods and apparatus for enhancing the robustness and stability of an electric machine having a rotor, stator and housing. The rotor includes a radially mounted array of permanent magnets and the stator includes a plurality of electromagnets radially positioned around the rotor. The rotor is stabilized by providing a first thermally conductive dielectric encapsulant in contact with adjacent permanent magnets. The stator is stabilized by providing a second thermally conductive dielectric encapsulant in contact with adjacent electromagnets.

Abstract: An electric machine having a rotor, stator and housing. The rotor includes a radially mounted array of permanent magnets and the stator includes a plurality of electromagnets radially positioned around the rotor. The stator is encapsulated such that the stator encapsulant is in thermal contact with housing structures, for example the housing end plates. In some embodiments, the entire perimeter portion of the housing is in thermal contact with the stator or the stator encapsulant. The stator encapsulant provides for device robustness and thermal transfer from the stator to the housing. The thermal conductivity of the encapsulant may be enhanced by mixing an additive to the encapsulant to increase thermal conductivity.

Abstract: A contactless recharging system and method for recharging a battery storage device onboard an electric vehicle has a primary converter station for converting power from a power source into high frequency power at a selected charging rate. The vehicle has a secondary converter for converting high frequency power into DC power to charge the battery. The converters are coupled together by a contactless coupling of a conductor loop and a coupling link forming a coaxial winding transformer. The coupled link and loop carry a communication indicating the selected charging rate of the battery. The link has a magnetic core and a core-mounted conductor at least partially surrounded by the core. The core-mounted conductor selectively at least partially surrounds a portion of the loop to transfer power therebetween. The core-mounted conductor is coupled to one of the converters, and the loop is coupled the other converter.

Abstract: A contactless power transfer system, especially for powering electric loads, hazardous loads or underwater loads and the like. A converter supplies high frequency power to a conductor loop. A coupling sheath or link has a core-mounted conductor at least partially surrounded by a magnetic core which slidably receives a portion of the conductor loop within the link. An optional secondary converter converts power from the core-mounted conductor to meet the load requirements. A contactless power distribution system delivers power to a variety of loads through clamped-on or captive links attached at any location along the conductor loop. Methods are also provided of powering a movable electric load, or a stationary load from a movable source, and of distributing power to a plurality of portable electric loads.

Abstract: A submersible contactless power transfer system, especially for powering underwater electric loads, including movable loads, such as underwater vehicles, elevators, or worksite equipment. A converter supplies high frequency power to a conductor loop. A coupling sheath or link has a core-mounted conductor at least partially surrounded by a magnetic core which slidably receives a portion of the conductor loop within the link. An optional secondary converter converts power from the core-mounted conductor to meet the load requirements. A contactless power distribution system is submersible to deliver power to underwater loads through clamped-on or captive links attached at any location along the conductor loop. Methods are also provided of powering loads submersed in water, including seawater, or other non-magnetic liquid mediums.