A bearing structure includes a drive shaft that extends in a horizontal direction, a touchdown bearing, and a bearing housing. The drive shaft is supported by a magnetic bearing. The touchdown bearing includes a rolling member interposed between an outer ring and an inner ring. The bearing housing supports the touchdown bearing from an outer periphery. At least one of an outer peripheral surface of the drive shaft, an inner peripheral surface of the inner ring, an outer peripheral surface of the outer ring, and an inner peripheral surface of the bearing housing includes a recess in a region overlapping the rolling member in a bearing radial direction.

An active magnetic bearing apparatus for supporting a rotor of a rotary machine comprises an axial magnetic bearing unit and a radial magnetic bearing unit mounted directly to one another. One of the axial magnetic bearing unit and the radial magnetic bearing unit is mounted to a support for attachment to a housing of the rotary machine.

A bearing structure includes a drive shaft that extends in a horizontal direction, a touchdown bearing, and a bearing housing. The drive shaft is supported by a magnetic bearing. The touchdown bearing includes a rolling member interposed between an outer ring and an inner ring. The bearing housing supports the touchdown bearing from an outer periphery. At least one of an outer peripheral surface of the drive shaft, an inner peripheral surface of the inner ring, an outer peripheral surface of the outer ring, and an inner peripheral surface of the bearing housing includes a recess in a region overlapping the rolling member in a bearing radial direction.

A magnetic bearing device for magnetically suspending a rotor (22) for rotation about a rotation axis (A) comprises an amplifier device, a first main coil (p) and a second main coil (n). In order to compensate for a stray flux that is created when the main coils are supplied with currents from the amplifier device, a compensation coil (c) is connected between a common node of the main coils and the amplifier device with such polarity that a current flowing through the compensation coil will diminish the stray flux caused by the main coils (p, n).

The present disclosure relates to a stiffness enhancing mechanism for a magnetic suspension bearing, a magnetic suspension bearing including the stiffness enhancing mechanism, and a blood pump. The magnetic suspension bearing comprises a stator with stator teeth and a rotor disposed within the stator. The stiffness enhancing mechanism comprises: a rotor permanent magnet, a stator permanent magnet, and an axial driving body. The rotor permanent magnet and the rotor of the magnetic suspension bearing form a rotor assembly, which has an asymmetric structure with respect to the main plane (P) of the rotor. The stiffness enhancing mechanism is configured such that the stator permanent magnet generates a radial attractive force to the rotor permanent magnet, and the axial driving body generates an axial repulsive force to the rotor permanent magnet, wherein the magnitude of the axial repulsive force is variable with a change of an axial distance between the axial driving body and the rotor permanent magnet). The stiffness enhancing mechanism can increase the torsional stiffness of the rotor of the magnetic suspension bearing and facilitate the miniaturization of the magnetic suspension bearing.

A first radial force value and a second radial force value is received by a radial magnetic bearing controller. Coefficients are computed for a first equation using the first and second radial force values. The first equation is solved to define first solution values. A second solution value paired with each first solution value is computed using the first radial force value and a respective first solution value to define second solution values. Control current sets are computed for each unique paired solution of the second solution values and the first solution values. Each control current set includes a control current value for each of three control currents. A control current value for each of the three control currents is selected from the control current sets. The control current value for each of the three control currents is output to a respective radial winding of a three-pole radial magnetic bearing.

An active magnetic rotor-bearing assembly for conveying a fluid comprising a rotor assembly is disclosed and a bearing assembly for contactless bearing the rotor assembly, where the bearing assembly comprises an even number of electromagnetic units arranged around a central structure each comprising a first salient established by a magnetic material and a permanent magnet providing a first magnetic pole and a coil around the salient, further comprises an inter-yoke with inter-yoke portions connected to the first salient of each electromagnetic unit and being separated from each other by structure spacers, providing a closed first magnetic flux passing the rotor assembly applying a first attractive force further comprising a position stabilizing portion perpendicular to the first attractive force on the rotor-assembly and the coils providing an electromagnetic flux between each first salient and the rotor assembly for applying adaptable axial force and/or tilting torque to the rotor assembly.

An electromagnetic rotary drive includes a magnetically contactlessly drivable rotor free of coils, and a stator configured as a bearing and drive stator configured to drive the rotor magnetically and contactlessly about an axis of rotation. The rotor is capable of being supported magnetically contactlessly with respect to the stator in an operating state. The stator includes an upper stator part having a plurality of pronounced upper poles configured to carry upper windings and a lower stator part having a plurality of pronounced lower poles configured to carry lower windings. The upper stator part and the lower stator part are arranged spaced apart from one another with respect to an axial direction. A permanent magnet is disposed between the upper stator part and the lower stator part.

A first radial force value and a second radial force value is received by a radial magnetic bearing controller. Coefficients are computed for a first equation using the first and second radial force values. The first equation is solved to define first solution values. A second solution value paired with each first solution value is computed using the first radial force value and a respective first solution value to define second solution values. Control current sets are computed for each unique paired solution of the second solution values and the first solution values. Each control current set includes a control current value for each of three control currents. A control current value for each of the three control currents is selected from the control current sets. The control current value for each of the three control currents is output to a respective radial winding of a three-pole radial magnetic bearing.

A turbine and a turbine-generator device for use in electricity generation. The turbine has a universal design and so may be relatively easily modified for use in connection with generators having a rated power output in the range of 50 KW to 5 MW. Such modifications are achieved, in part, through use of a modular turbine cartridge built up of discrete rotor and stator plates sized for the desired application with turbine brush seals chosen to accommodate radial rotor movements from the supported generator. The cartridge may be installed and removed from the turbine relatively easily for maintenance or rebuilding. The rotor housing is designed to be relatively easily machined to dimensions that meet desired operating parameters.