A gas laser apparatus includes: a magnetic bearing including an electromagnet capable of controlling a magnetic force, and configured to rotatably support a rotary shaft of a fan in a magnetically levitated state by the magnetic force, the fan being configured to supply a laser gas; an electromagnet control unit configured to control the magnetic force of the electromagnet based on displacement of a levitated position of the rotary shaft and adjust the levitated position; a motor configured to generate torque for rotating the fan; a magnetic coupling configured to couple the rotary shaft and a drive shaft of a motor with a magnetic attractive force and transmit the torque of the motor to the rotary shaft; an attractive force estimating sensor configured to detect a parameter that enables an attractive force of the magnetic coupling to be estimated; an attractive force measuring unit configured to measure the attractive force of the magnetic coupling based on the detected parameter; and a correction unit configured to correct the magnetic force of the electromagnet according to a variation in the attractive force measured by the attractive force measuring unit.

An electric submersible pump (ESP) assembly. The ESP assembly comprises a centrifugal pump, an electric motor mechanically coupled by a drive shaft to the centrifugal pump, wherein the electric motor comprises a stator and a rotor, a bearing, wherein the bearing is disposed inside the electric motor, and a magnetic shield disposed in the electric motor between bearing and the rotor and stator.

A centrifugal compressor includes a tubular shape casing extending in an axial direction, a motor stator fixed to an inside of the casing in a radial direction, a shaft disposed inside of the motor stator in the radial direction and extending in the axial direction, a motor rotor fixed to the shaft and facing the motor stator with a gap in the radial direction, a compression unit fixed to an end portion of the shaft on one side in the axial direction, a first thrust magnetic bearing disposed between the motor rotor and the impeller in the axial direction, and a second thrust magnetic bearing disposed on an other side in the axial direction relative to the motor rotor. A magnetic attraction force of the second thrust magnetic bearing toward the other side is larger than a magnetic attraction force of the first thrust magnetic bearing toward the one side.

A bearingless hub assembly comprising a rim hollowed to receive a tube magnet, and magnets embedded around the circumference of the rim on both ends. The rim is capped by front and rear rim plates configured to hold the embedded magnets in place and fitted to receive respective circular magnets. Similar magnets in corresponding front or rear drive plate maintain space (i.e., levitation) vis-à-vis the front and rear rim caps by repelling each other, thus allowing the rim (and, as applied, a mechanically-attached tire assembly) to move freely with no friction. The front and rear drive plate carry forward and reverse electromagnetic actuators as well as forward and reverse levitation control units, power generators and speed sensors. These components mount 360 degrees around the circumference of the drive plates while the embedded magnets of the rim spin through when in motion.

A system for compensating for the stresses applied to a bearing that rotatably supports a rotor shaft of a rotating machine relative to a stator of the machine. The system provides at least one sensor for measuring an input signal positioned on an element of the bearing, a module for acquiring the input signal configured to convert the input signal into a value of the deformation applied to the rolling bearing, a module for determining a compensation signal as a function of the deformation value, and an amplifier module configured to control a magnetic actuator rotatably supporting the shaft of the rotor and including at least one electromagnet, the amplifier module being configured to convert the compensation signal into a voltage signal transmitted to the electromagnet of the magnetic actuator, the magnetic actuator being configured to exert a force on the rotor shaft as a function of the voltage signal.

A hub for partially muscle-powered vehicles, including a hollow hub axle with a cylindrical inner through hole for the passage of a clamping axle, a hub shell rotatably supported relative to the hub axle by two hub bearings, a rotor rotatably supported relative to the hub axle, and a freewheel device with a hub-side freewheel component and a rotor-side freewheel component, each having axial engagement components for engagement with one another. The hub shell is rotatably supported relative to the hub axle in a rotor-side end region by a rotor-side hub bearing, and in an opposite end region of the hub shell by another hub bearing. The hub-side freewheel component is non-rotatably connected with the hub shell. The rotor-side freewheel component is non-rotatably connected with the rotor and is movable in the axial direction relative to the rotor and the hub shell between a freewheel position and an engagement position.

An electrical drive includes an electrical machine, a first converter stage connected to terminals of stator phase-windings of the electrical machine, and a second converter stage connected to intermediate points of the stator phase-windings. A control device determines first component currents and second component currents so that torque is generated in accordance with electrical machine control and magnetic levitation force is directed to a rotor of the electrical machine in accordance with levitation control when portions of the phase-windings between the terminals and the intermediate points carry both the first and second component currents and the other portions of the phase-windings carry the first component currents. The reference currents for the first converter stage are determined based on the first and second component currents, and the reference currents for the second converter stage are determined based on the second component currents.

A rotating machine including a thrust bearing configured to receive an axial thrust exerted by a rotor. The thrust bearing may be configured to transfer the axial thrust from the rotor to a housing or other structural component of the rotating machine using a plurality of ball bearings. The rotating machine includes a magnetic apparatus configured to cause the rotating machine to exert an axial force on the thrust bearing in the direction of the axial thrust of the rotor, such that the magnetic apparatus loads the ball bearings in the direction of the axial thrust. The magnetic apparatus may be configured to generate a magnetic field causing a first magnetic component of the magnetic apparatus to repel or attract a second magnetic component of the apparatus. The first magnetic component may be configured to rotate relative to the second magnetic component.

A first thrust bearing includes a first electromagnet and a first member. A second thrust bearing includes a second electromagnet and a second member. A magnetic force generated by the first electromagnet and the second electromagnet, and dynamic gas pressure generated by the first member and the second member due to rotation of a rotating shaft support an axial load of the rotating shaft.

A magnetic bearing device includes a magnetic bearing including a plurality of electromagnets, a displacement sensor configured to output an output signal in accordance with a displacement of a shaft, and a controller configured to control the electromagnets. The controller compensates for a change in levels of the output signal, the change occurring in accordance with a change in ambient temperature around the displacement sensor, based on one or more reference values correlating with the change in levels of the output signal. The one or more reference values are detected for use in controlling the rotary electric machine, a fluid machine system including the rotary electric machine, or an apparatus including the fluid machine system.