An electric motor (20) usable in proximity to a magnetic resonance imaging (MRI) device (4) includes a stator (30) comprising electrical windings (32), and a rotor (40, 50, 60) magnetically coupled with the stator. The electric motor does not include ferromagnetic material, and the electric motor does not include any permanent magnet. The rotor may include an outer rotor cylinder (50, 60) surrounding the stator, and may further include an inner rotor cylinder (40) disposed inside the stator and connected to rotate with the outer rotor cylinder. The rotor may comprise a cylindrical sheet rotor (40, 50). Alternatively, the rotor (60) may comprise one or more conductive loops (62A, 62B, 62C) each shaped such that the induced voltage in one loop portion (HL1) cancels the effect of the induced voltage in another loop portion (HL2), and a coupled split stator (301, 302). In another disclosed aspect, an infusion pump (10) includes the electric motor.

A rotor for an electric machine includes a central hub with a cylindrical outer surface. A plurality of elongate spacers are affixed to the central hub at its outer surface. The spacers are circumferentially spaced apart from each other and extend axially along the outer surface of the central hub. A plurality of permanent magnets reside on the outer surface between the spacers. The magnets define at least two magnetic poles of the rotor. A metallic shield surrounds an outward facing surface of the permanent magnets and spacers to shield the magnets from high frequency magnetic fields that would cause eddy currents, and thus magnet heating. The metallic shield includes a metallic foil. A carbon fiber retaining sleeve surrounds an outward facing surface of the metallic shield. The carbon fiber sleeve is configured to retain the magnets to the central hub during operation of the electric machine.

A rotor for an electric machine has a permanent magnet carrier that defines a plurality of permanent magnet receptacles. A plurality of permanent magnets are received in the receptacles. The magnets are arranged to define at least two magnetic poles of the rotor. A metallic shield surrounds an outward facing surface of the permanent magnets to shield the magnets from high frequency magnetic fields that would cause eddy currents, and thus magnet heating. The metallic shield is constructed from a metallic foil. A carbon fiber retaining sleeve surrounds an outward facing surface of the metallic shield. The carbon fiber sleeve is configured to retain the magnets to the permanent magnet carrier during operation of the electric machine. The permanent magnet carrier is interference fit over a rotor core.

An electric motor includes: a stator; a shaft; a rotor mounted on the shaft, the rotor having an end ring that is concentric with the shaft; and a flux shield around the shaft inside the end ring.

An annular rotating armature is presented. The annular rotating armature includes an armature winding having a plurality of coils, an armature support structure and a magnetic shield disposed between the armature winding and the armature support structure. The magnetic shield having a first magnetic shield ring, a second magnetic shield ring disposed concentric to the first magnetic shield ring and coupled to the first magnetic shield ring via a magnetic shield bridge link. An air gap is formed between the first magnetic shield ring and the second magnetic shield ring. The magnetic shield bridge link is disposed within the air gap. A superconducting generator including the annular rotating armature and a wind turbine having such superconducting generator are also presented.

The present disclosure relates to a double air gap surface permanent magnet synchronous motor with two controllers, and particularly, to a double air gap surface permanent magnet synchronous motor with two controllers, which doubles structures of a rotor and a stator to improve torque performance and has high efficiency and a high power density that satisfy an international efficiency class IE5 of International Electro-technical Commission (IEC) and solves failures by including individual controllers. According to an embodiment the present disclosure, a double air gap surface permanent magnet synchronous motor with two controllers, includes a first stator including first protrusions formed on a first inner circumferential surface, a first rotor including a first outer circumferential surface facing the first inner circumferential surface, first permanent magnets arranged on the first outer circumferential surface, a second rotor integrally connected to the first rotor to correspond to an inside of the first rotor and including a second inner circumferential surface, second permanent magnets arranged on the second inner circumferential surface, a second stator including second protrusions formed on a second outer circumferential surface formed to face the second inner circumferential surface, a partition wall portion formed at a boundary between the first rotor and the second rotor, a first controller for controlling a first winding wire wound around the first protrusions, and a second controller for controlling a second winding wire wound around the second protrusions.

An annular rotating armature is presented. The annular rotating armature includes an armature winding having a plurality of coils, an armature support structure and a magnetic shield disposed between the armature winding and the armature support structure. The magnetic shield having a first magnetic shield ring, a second magnetic shield ring disposed concentric to the first magnetic shield ring and coupled to the first magnetic shield ring via a magnetic shield bridge link. An air gap is formed between the first magnetic shield ring and the second magnetic shield ring. The magnetic shield bridge link is disposed within the air gap. A superconducting generator including the annular rotating armature and a wind turbine having such superconducting generator are also presented.

Disclosed are an electric motor and a simplified variable speed drive system which renders the use of filtering components in a motor drive circuit unnecessary and increases torque transfer from permanent magnets of the rotor to the output shaft. The motor includes a fluid gap between the rotor and the stator configured to receive a cooling fluid, such a refrigerant. A plurality of radially-abutting, bread loaf-shaped magnets having a flat base are respectively fixed to a plurality of longitudinally oriented mounting facets provided on the shaft to provide maximum torque transfer from the magnets to the shaft. An eddy shield disposed between the faceted shaft and the magnets thermally shunts high frequency harmonics from the magnets to the shaft and cooling fluid. The rotor components are mechanically secured by a sleeve disposed around the rotor.

The rotor includes an annular permanent magnet, an annular first iron core situated on the inner diameter side of the magnet, an annular second iron core situated on the inner diameter side of the first iron core, an insulating member situated between the first iron core and the second iron core, and a shaft provided along a central axis of the second iron core, the first iron core is provided with a plurality of outer periphery side convex portions protruding from an inner periphery toward the inner diameter side, the second iron core is provided with a plurality of inner periphery side convex portions protruding from an outer periphery toward the outer diameter side, and the outer periphery side convex portions and the inner periphery side convex portions are disposed in positions not overlapping each other when viewed in the radial direction from the axis of the second iron core.

A motor rotor may include a body having axially extending first and second magnets embedded into the body, the first magnet and the second magnet being arranged at an angle and spaced apart by an axially extending magnetic shielding component. The first magnet includes a first surface away from a central axis of the rotor body and a second surface facing the central axis. The second magnet includes a third surface away from the central axis and a fourth surface facing the central axis, wherein the first surface and the third surface and extension surfaces thereof define a first area of the body part away from the central axis and a second area of the body part close to the central axis.