A short-circuit generator is a generator in which stator slots provided with windings of a stator placed therein each have a depth in a radial direction perpendicular to a rotor central axis whose ratio divided by a width of the stator slot in a direction perpendicular both to the radial direction and a direction of the rotor central axis, is less than three. A rotor includes: a field winding placed in each of rotor slots; a metallic damper bar placed in each of the rotor slots on an outer periphery side of the field winding; and a metallic wedge placed in each of the rotor slots on an outer periphery side of the damper bar and connected to the damper bar. A damper-bar height that is a height of the damper bar is less than a wedge height that is a height of the wedge in the radial direction.

A method for manufacturing a stator for an electric machine comprises manufacturing a slot cooling fin to extend into a slot defined between a first tooth, a second tooth, and a stator yoke, and disposing a coil in the slot, wherein the slot cooling fin extends into the first coil.

A method for manufacturing a stator for an electric machine comprises manufacturing a slot cooling fin to extend into a slot defined between a first tooth, a second tooth, and a stator yoke, and disposing a coil in the slot, wherein the slot cooling fin extends into the first coil.

An example system includes a dynamo-electric machine. The dynamo-electric machine includes a rotor that is cylindrical and that is configured for rotation and a stator that is arranged relative to the rotor. The stator has a stepped configuration that defines a first diameter for the stator and a second diameter for the stator. The first diameter is greater than the second diameter. Zones of the stator at the first diameter hold direct-axis (D-axis) windings and zones of the stator at the second diameter hold quadrature axis (Q-axis) windings. An airgap between the rotor and the Q-axis windings is greater than an airgap between the rotor and the D-axis windings.

An example system includes a dynamo-electric machine. The dynamo-electric machine includes a rotor that is cylindrical and that is configured for rotation and a stator that is arranged relative to the rotor. The stator has a stepped configuration that defines a first diameter for the stator and a second diameter for the stator. The first diameter is greater than the second diameter. Zones of the stator at the first diameter hold direct-axis (D-axis) windings and zones of the stator at the second diameter hold quadrature axis (Q-axis) windings. An airgap between the rotor and the Q-axis windings is greater than an airgap between the rotor and the D-axis windings.

An electric motor comprises a stator presenting a first surface. A rotor is rotatable relative to the stator. The rotor presents a rotor raceway disposed in spaced relationship with the first surface of the stator. The first surface of the stator defines a plurality of slots in spaced relationship with one another to define a plurality of spaced teeth between the slots. At least one electrical conductor is disposed in each of the slots and configured to selectively create a moving magnetic field for acting upon the rotor for providing rotational movement of the rotor. A portion of the at least one electrical conductor extends substantially into radial alignment with, or past the first surface of the stator to at least partially define a stator raceway of the stator for engaging the rotor raceway of the rotor during relative radial movement between the rotor and the stator.

An electric motor comprises a stator presenting a first surface. A rotor is rotatable relative to the stator. The rotor presents a rotor raceway disposed in spaced relationship with the first surface of the stator. The first surface of the stator defines a plurality of slots in spaced relationship with one another to define a plurality of spaced teeth between the slots. At least one electrical conductor is disposed in each of the slots and configured to selectively create a moving magnetic field for acting upon the rotor for providing rotational movement of the rotor. A portion of the at least one electrical conductor extends substantially into radial alignment with, or past the first surface of the stator to at least partially define a stator raceway of the stator for engaging the rotor raceway of the rotor during relative radial movement between the rotor and the stator.

A reciprocating motor and a reciprocating compressor having a reciprocating motor are provided. The reciprocating motor may include a stator having a magnet coil, provided with an air gap respectively formed at both sides in an axial direction by interposing the magnet coil therebetween; a mover inserted into the stator, reciprocating with respect to the stator as at least one magnet is arranged at any one of the air gaps formed at both sides and a non-magnet is arranged at the other one of the air gaps; and a magnetic resonance spring that resonates the mover with respect to the stator using a force for moving toward low magnetic resistance between the mover and the stator. The reciprocating motor and the reciprocating compressor having a reciprocating motor may be downsized and lightweight, and may obtain high efficiency.

Disclosed is a hermetic AC electric motor that includes harmonics shunting such that high frequency harmonics are shunted from the AC electric motor without the use of one or more high frequency filters in the associated motor drive. A related method of operating an AC electric motor includes shunting high frequency harmonics to a fluid passing through the AC electric motor. Also disclosed is a simplified variable speed motor drive system which eliminates the need for a filter for removing high frequency harmonics.

An electric machine (10) comprises a stator (11), which comprises at least two slots (12) in which each at least one electrically conductive bar (13) is arranged, respectively. The stator (11) is adjacent to an air gap (14) and the at least two electrically conductive bars (13) form an electric winding (15) of the stator (11) and are arranged to be supplied with a corresponding electrical phase (n), respectively, by a power supply (16). Furthermore, the stator (11) is arranged in such a way that during operation of the electric machine (10) a stator magnetic field with at least two magnetic poles is formed in the air gap (14), where at least a first pole (22) has a circumferential extent along the air gap (14) which is different from the circumferential extent of at least a second pole (23).