The present invention is a stator core (21) including a plurality of split cores (30), in which the plurality of split cores (30) are configured by laminating core pieces (40) made of an electrical steel sheet, the electrical steel sheet is a predetermined electrical steel sheet, and, in the core pieces (40) of at least one split core (30) in the plurality of split cores (30), the radial directions of teeth (41) and extension directions of core backs (42) are all along a direction in which magnetic characteristics of the electrical steel sheet are excellent.

Provided is a stator including a coil of a winding of a flat wire conductor, a stator core including a slot for housing a part of the coil, and a flow passage part through which a coolant flows, provided between a wall part of the slot and an outer surface of the coil facing the wall part. The extension shape of the flow passage part from an inlet to an outlet for the coolant changes along the axial direction of the stator core. The flow passage part is, for example, a concave part formed on the wall part of the slot.

The present invention may provide a motor including a rotor, a stator disposed to correspond to the rotor, and a housing disposed outside the stator, wherein the stator includes a stator core, an insulator disposed on the stator core, and a coil disposed around the insulator, the stator core includes a yoke and a tooth connected to the yoke, the yoke includes one surface, a first protrusion protruding from the one surface of the yoke, and a first groove formed in the one surface of the yoke, the housing includes the other surface facing the one surface of the yoke, a second protrusion protruding from the other surface of the housing, and a second groove formed in the other surface of the housing, at least a part of the first protrusion is disposed in the second groove, and a predetermined gap is formed between the one surface of the yoke and the other surface of the housing.

A motor driving device is a device for driving a motor including stator windings, includes: a connection switching unit that is connected to the stator windings, includes circuits including semiconductor switches, and switches connection condition of the stator windings to either of first connection condition and second connection condition different from the first connection condition by setting the semiconductor switches to ON or OFF; and an inverter that supplies AC drive voltages to the stator windings.

A liquid-cooled rotating electric machine may include an inner stator and outer rotor configured to rotate about the stator. A hub may be disposed within the inner stator and a heat exchanger may be disposed in the hub. The heat exchanger may be configured to enable the flow a liquid through it to dissipate heat from the stator.

A homopolar multi-core energy conversion device is an apparatus that uses magnetic flux commutation instead of a combination of electrical current commutation and brushes. The apparatus includes a first discontinuous annular stator core, a second discontinuous annular stator core, and a rotor core. The first discontinuous annular stator core is configured to generate a circumferentially-segmented clockwise magnetic flux around the rotor core, while second discontinuous annular stator core is configured to generate a circumferentially-segmented counter-clockwise magnetic flux around the rotor core. The rotor core is configured to radially partition a traversing magnetic flux. The circumferentially-segmented clockwise magnetic flux, the circumferentially-segmented counter-clockwise magnetic flux, and the traversing magnetic flux interact with each other so that the apparatus can function either as a motor or as a generator. The aforementioned components of the apparatus can be configured into different embodiment to achieve the same function.

An electric motor for reciprocating an object along a rod having a predetermined length is provided, comprising: a housing; a rotor unit that is mounted to the inside of the housing via a bearing to be rotatable and comprises a rotor shaft, which is axially-coupled to the rod to linearly reciprocate along the rod during rotation, and a plurality of magnets mounted along the circumference direction of the rotor shaft; and a stator unit comprising at least one stator core and a coil, the at least one stator core comprising a yoke portion of a closed loop shape that is built in the housing so as to surround the circumference of the rotor unit, and a plurality of slot portions extending from the yoke portion toward the rotor, and the coil being wound around at least one slot portion among the plurality of slot portions.

A stator structure of a vehicle motor includes a stator core assembly and a plurality of coil assemblies composed of flat wires. The stator core assembly includes an annular portion and a plurality of tooth portions. The tooth portions extend from the annular portion in a radial direction toward a center of the stator core assembly. Each coil assembly is configured around a corresponding tooth portion. Each coil assembly includes a first flat wire and a plurality of second flat wires that are electrically connected in parallel. The first flat wire is radially stacked and wound around the corresponding tooth portion. The second flat wires are arranged radially adjacent to the first flat wire and are electrically connected in series to the first flat wire. The second flat wires are alternately stacked and radially wound around the corresponding tooth portion.

Methods and systems are provided for operating an electric motor including multiple rotor and stator sections. In one example, a system may include the multiple rotor sections configured to be mechanically coupled and decoupled from each other concurrently with multiple stator sections configured to be electrically coupled and decoupled from each other, within certain regimes of operation of the electric motor.

A brushless motor comprising a frame; a rotor assembly comprising a shaft, a rotor core and a bearing assembly, the bearing assembly being mounted to the frame; and at least one stator comprising a C-shaped stator core, the stator core comprising a back and first and second arms, wherein at least one of the first and second arms includes a protrusion that contacts the frame so as to inhibit radial movement of the stator core towards the rotor assembly.