A flywheel energy storage system incorporates various embodiments in design and processing to achieve a very high ratio of energy stored per unit cost. The system uses a high-strength steel rotor rotating in a vacuum envelope. The rotor has a geometry that ensures high yield strength throughout its cross-section using various low-cost quenched and tempered alloy steels. Low-cost is also achieved by forging the rotor in a single piece with integral shafts. A high energy density is achieved with adequate safety margins through a pre-conditioning treatment. The bearing and suspension system utilizes an electromagnet that off-loads the rotor allowing for the use of low-cost, conventional rolling contact bearings over an operating lifetime of several years.

A laminated core can be contained in a rotor and/or in a stator and include at least one first sheet metal part assembly and at least one second sheet metal part assembly. The two sheet metal part assemblies are arranged alternately lying one against the other in a stacking direction. Every first sheet metal part has first teeth projecting from a connecting part radially relative to the axis of rotation. Correspondingly, every second sheet metal part has second teeth projecting from a second connecting part. The first teeth extend from the axis of rotation at a distance different from how far the second teeth extends from the axis of rotation to form a step to mesh the rotor with an associated stator and increase the air gap between them without increasing dimensions of the laminated cores in the stacking direction.

A rotor of an electric machine is disclosed that resists expansion of the rotor components even at high rotational speed. The rotor includes first and second pluralities of laminations having slots to accept rotor bars. A support disk, also having slots, is placed between the laminations. The support disk, into which the rotor bars are slid, restrains the rotor bars from bending outwardly at high rotational speeds of the rotor. The rotor bars are further restrained at the ends by end rings, which have apertures into which ends of the rotor bars are placed. In some embodiments, containment rings are placed over axial extension of the end rings to prevent outward bowing at high speeds. In some embodiments, the rotor includes a stiffener sleeve to provide additional resistance to expansion during high rotational speeds.

A manufacturing method of a rotor for an electric motor is disclosed herein. The rotor may include a rotor core having a through hole that extends along an axial direction of the rotor; a magnet inserted in the through hole; and a sheet disposed between an inner surface of the through hole and the magnet. The method may include inserting the sheet into the through hole such that the sheet extends through the through hole; and inserting the magnet into the through hole while the sheet is pulled at axial ends of the sheet in opposite directions to apply tension to the sheet and press the sheet against the inner surface.

A rotor including: a shaft; a structure comprising at least one end ring and rotor bars, wherein at least the end ring comprises a material subject to expansion or movement radially outward from the shaft upon a rotor balancing process that involves spinning of the structure; a core that at least partially encloses the rotor bars; and means for limiting the expansion or movement of the structure radially outward. A method including: providing a structure comprising at least one end ring and rotor bars, wherein at least the end ring comprises a material subject to expansion or movement radially outward from the shaft upon spinning of the structure; assembling a rotor from the structure and a core, the core at least partially enclosing the rotor bars; spinning the rotor in a rotor balancing process; and limiting the expansion or movement of the structure radially outward in the rotor balancing process.

A modular compressor assembly comprises a common motor assembly, an impeller, a blower housing and an engagement mechanism. The common motor assembly includes a stator housing containing a stator assembly and having a rotor magnet rotatably disposed therewithin. The impeller is mounted to and rotatable with the rotor magnet. The blower housing is selectable from among a plurality of blower housings each having a different cross-sectional geometry. The engagement mechanism is formed on the stator housing and/or the blower housing and allows interchangeable mounting of different blower housing configurations to the common motor assembly in order to achieve varying flow characteristics of the compressor assembly.

The invention concerns a windmill including a rotatable transverse flux electrical machine (TFEM) comprising a stator portion; and a rotor portion rotatably located in respect with the stator portion, the rotor portion including an alternate sequence of magnets and concentrators radially disposed about a rotation axis thereof; the stator portion including at least one phase, the at least one phase including a plurality of cores cooperating with a coil disposed about the rotation axis, each core including a skewed pair of poles to progressively electromagnetically engage an electromagnetic field of respective cooperating concentrators. The invention is also concerned with a plurality of elements located in desired positions in the TFEM.

Embodiments of a gas turbine engine actuation system are provided, as are embodiments of a high temperature actuator and methods for the manufacture thereof. In one embodiment, the gas turbine engine actuation system includes an actuated gas turbine engine component and a high temperature actuator, which has a rotor mechanically linked to the actuated gas turbine engine component and a stator surrounding at least a portion of the rotor. The stator includes, in turn, a coil support structure having a plurality of spokes extending radially therefrom. A plurality of pre-formed electromagnetic coils is circumferentially distributed about the coil support structure. Each of the plurality of pre-formed electromagnetic coils is inserted over at least one of the plurality of spokes in a radial direction. The stator further includes an inorganic dielectric material in which each of the plurality of pre-formed electromagnetic coils is at least partially embedded.

Cooling assemblies and methods, including, for example, at least one bar (e.g., electrically insulated and/or thermally conductive bar(s)), members (e.g., i-beams, rectangular members, and the like), stator laminations, rotor laminations, and/or combinations thereof, such as those configured to cool electric machines (e.g., electric motors and generators).

A method for coupling a permanent magnet to a rotor body of an electric motor includes providing a rotor body having an outer surface. A mounting hole is formed in the rotor body. A permanent magnet in the form of an annular section is provided. The concave surface of the permanent magnet has a diameter generally equal to the outer diameter of the rotor body. The permanent magnet has a hole formed therein to receive the threaded connector, the hole having a countersink at the convex surface of the permanent magnet. The permanent magnet is positioned on the outer surface of the rotor body such that the hole lines up with the mounting hole, an elastomeric body is positioned in the countersink, and the threaded connector is positioned through the elastomeric body and the hole of the permanent magnet to couple to the rotor body.