An electric motor system includes a drive shaft, first and second magnetic bearing portions facing each other and supporting the drive shaft, an electric motor to rotate the drive shaft, and a gap detection unit to detect a position of the drive shaft During rotation of the drive shaft, greater external force acts, on average, on the drive shaft in a first direction than in a second direction. The first and second direction extend from the second and first magnetic bearing portions to the first and second magnetic bearing portion. The first and second magnetic bearing portions produce first and second magnetic forces on the drive shaft in the first and second directions. A magnitude of the second magnetic force is greater than a magnitude of the first magnetic force. The gap detection unit is arranged closer to the second magnetic bearing portion than to the first magnetic bearing portion.

A magnetic levitation motor has a housing, a plurality of stators and a plurality of rotors. The housing has a shaft hole there through, the shaft hole accepting a bearing, the bearing rotatably engages with a rotating shaft that extends from two ends of the housing, and a plurality of fastening portions are disposed on the rotating shaft. A main body section is disposed between at least two of the fastening portions, and the housing having a plurality of dividers to define a plurality of containing spaces. The stator has a fixing disk wrapped with a coil and having a through aperture the fixing disk, and the fixing disk has a plurality of first magnets circularly and radially arranged. The rotor has a moving disk with a toothed hole at a center the moving disk, and the moving disk having a plurality of second magnets arranged circularly and radially.

A refrigerant compressor includes a magnetic bearing assembly including insulation for the coils and lamination stack of the assembly. The lamination stack includes coil apertures extending axially between opposed axial faces. An insert partially extends into a first coil aperture to prevent direct contact between first and second coils. The insert includes a first leg extending into a slot formed in the lamination stack and a second leg radially spaced-apart from the first leg with the second leg extending axially into the first coil aperture. An annular cover having first and second legs extends into respective slots and apertures of the lamination stack. A second annular cover is provided on the opposite face of the coils that is connected to free ends of the second legs. The lamination stack and coils are coated with an insulative material such as epoxy.

A refrigerant compressor includes a magnetic bearing assembly including insulation for the coils and lamination stack of the assembly. The lamination stack includes coil apertures extending axially between opposed axial faces. An insert partially extends into a first coil aperture to prevent direct contact between first and second coils. The insert includes a first leg extending into a slot formed in the lamination stack and a second leg radially spaced-apart from the first leg with the second leg extending axially into the first coil aperture. An annular cover having first and second legs extends into respective slots and apertures of the lamination stack. A second annular cover is provided on the opposite face of the coils that is connected to free ends of the second legs. The lamination stack and coils are coated with an insulative material such as epoxy.

Modified magnetic levitation system for flying vehicle Modified magnetic levitation system for flying vehicle includes a propeller system (11, 12, 13), an axial levitation system (101, 102), radial levitation system (part of 201), rotary propulsion system (part of 201) and passive magnetic bearing system (301). An axial levitation system includes plurality of halbach array pairs connected on rotor and special short circuited coil windings connected on stator. A propulsion mechanism (part of 201) is provided for rotating rotor along the centre axis. Radial levitation and propulsion system (201) includes halbach arrays (53) located at outer circumference of rotor and interweaved active and passive coil windings (43) located at inner circumference of stator. Passive magnetic bearing system (301) includes parts of rotor and stator around centre axis of the system. Passive magnetic bearing (PMB) is utilized to levitate rotor at rest, below lift-off speed, and start and end condition of rotations.

This disclosure relates to an axial magnetic bearing for a centrifugal refrigerant compressor, and a corresponding system and method. A centrifugal refrigerant compressor system according to an exemplary aspect of the present disclosure includes, among other things, an impeller connected to a shaft, and a magnetic bearing system supporting the shaft. The magnetic bearing system includes an axial magnetic bearing, which itself includes a first permanent magnet configured to generate a first bias flux, a second permanent magnet axially spaced-apart from the first permanent magnet and configured to generate a second bias flux, and an electromagnet. The electromagnet includes a coil arranged radially outward of the first and second permanent magnets, and the electromagnet is configured to selectively generate either a first control flux or a second control flux to apply a force to the shaft in a first axial direction or second axial direction opposite the first axial direction, respectively.

This disclosure relates to an axial magnetic bearing for a centrifugal refrigerant compressor, and a corresponding system and method. A centrifugal refrigerant compressor system according to an exemplary aspect of the present disclosure includes, among other things, an impeller connected to a shaft, and a magnetic bearing system supporting the shaft. The magnetic bearing system includes an axial magnetic bearing, which itself includes a first permanent magnet configured to generate a first bias flux, a second permanent magnet axially spaced-apart from the first permanent magnet and configured to generate a second bias flux, and an electromagnet. The electromagnet includes a coil arranged radially outward of the first and second permanent magnets, and the electromagnet is configured to selectively generate either a first control flux or a second control flux to apply a force to the shaft in a first axial direction or second axial direction opposite the first axial direction, respectively.

A motor including a first part having an outer peripheral portion and a second part having an inner peripheral portion facing the outer peripheral portion, the first part and the second part being configured to rotate relative to each other, includes a plurality of coils on one of the outer peripheral portion and the inner peripheral portion, and a plurality of magnets on the other of the outer peripheral portion and the inner peripheral portion at positions facing the plurality of coils, wherein the plurality of magnets includes a first magnet portion configured to apply a thrust to at least one of the plurality of coils in a rotation direction and a second magnet portion configured to apply a thrust to at least one of the plurality of coils in a direction intersecting the rotation direction, when an electric current is applied to the plurality of coils.

The present invention discloses a magnetic bearing of a stator permanent magnet motor with magnetic pole bypasses and a bias force adjusting method thereof, and belongs to the technical field of power generation, power transformation or power distribution. A typical magnetic field loop formed by permanent magnets extending out of stator sections, radial magnetic conduction bridges, circumferential magnetic conduction bridges, magnetic collecting shoes, radial/axial working air gaps and magnetic conduction blocks of radial/axial magnetic field closed main loops is used for designing the magnetic pole bypasses, so as to achieve the distribution of the magnetic field energy with multiple paths and controllable magnetic field strength of the permanent magnets in the stator permanent magnet motor. The present invention further provides a bias magnetic circuit structure. The number of magnetic poles and the magnetic field strength of a bias magnetic field are adjusted by selecting the materials of connecting sections between magnetic collecting blocks and the volume embedded in adjacent magnetic collecting blocks, so as to adjust the bias force of the magnetic pole, the space at an end of a motor winding is used to the greatest extent, the axial length of a magnetic suspension bearing motor system is reduced, the dynamic performance of a rotor is improved, and the objectives of high compactness and high integration level of “a magnetic suspension bearing and a permanent magnet motor system” are achieved.

The present invention discloses a magnetic bearing of a stator permanent magnet motor with magnetic pole bypasses and a bias force adjusting method thereof, and belongs to the technical field of power generation, power transformation or power distribution. A typical magnetic field loop formed by permanent magnets extending out of stator sections, radial magnetic conduction bridges, circumferential magnetic conduction bridges, magnetic collecting shoes, radial/axial working air gaps and magnetic conduction blocks of radial/axial magnetic field closed main loops is used for designing the magnetic pole bypasses, so as to achieve the distribution of the magnetic field energy with multiple paths and controllable magnetic field strength of the permanent magnets in the stator permanent magnet motor. The present invention further provides a bias magnetic circuit structure. The number of magnetic poles and the magnetic field strength of a bias magnetic field are adjusted by selecting the materials of connecting sections between magnetic collecting blocks and the volume embedded in adjacent magnetic collecting blocks, so as to adjust the bias force of the magnetic pole, the space at an end of a motor winding is used to the greatest extent, the axial length of a magnetic suspension bearing motor system is reduced, the dynamic performance of a rotor is improved, and the objectives of high compactness and high integration level of “a magnetic suspension bearing and a permanent magnet motor system” are achieved.