In an electric motor, a magnetic bearing generates an electromagnetic force between multiple permanent magnets and a coil and rotatably supports an other side of a rotation shaft in an axis line direction. The rotation shaft is configured to be capable of being inclined with a rotation center line using a bearing side of the rotation shaft as a fulcrum. An electronic control device controls a current that flows to the coil such that an axis line of the rotation shaft approaches the rotation center line due to a supporting force which is the electromagnetic force between the multiple permanent magnets and the coil. Accordingly, the rotation shaft is rotatably supported to be freely rotatable by a magnetic bearing and the bearing.

A magnetic bearing assembly is for levitating a generally drum-shaped, vertical rotor such that the drum itself is the target of magnetic actuators. The magnetic bearing assembly basically includes at least one active radial actuator configured to center the drum-shaped rotor in an annular air gap so as to enable contactless rotation. The one or more radial actuators are configured to act principally against gravity and is/are located in essentially the same vertical plane as a center of gravity of the drum-shaped rotor.

A system for suspending a rotating body consisting of a combination of magnetic and engineered materials. The suspension system allows for some axial motion to account for varying system loads.

An electric submersible pump (ESP) assembly. The ESP assembly comprises an electric motor, a centrifugal pump, and a hybrid magnetic radial bearing, wherein the hybrid magnetic radial bearing is disposed inside the electric motor or disposed inside the centrifugal pump.

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 motor includes a bearing having a rolling member disposed between an inner ring and an outer ring, a spring connected to the outer ring, and a pusher connected to the spring and configured to move to a first position spaced apart from the inner ring by the spring. The pusher is further configured to move to a second position at which friction with the inner ring is caused by a pressure of air. The inner ring is spaced apart from the rotating shaft by a gap between the inner ring and the rotating shaft when the pusher is at the second position.

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.

In certain embodiments, apparatus for self-aligning elements of coupled platforms includes a radially repulsive magnetic bearing. The radially repulsive magnetic bearing includes a first axially polarized magnet and a second axially polarized magnet that is concentrically disposed around the first axially polarized magnet and radially repulsive to the first axially polarized magnet. The radially repulsive magnetic bearing is configured to align a first element of a first platform with a second element of a second platform when the first and second platforms are coupled together.

A system for controlling an electric motor including a rotor supported by a lubricant upon a stator with a plurality of stator poles and stator windings includes monitoring a radial position and rotor angle of the rotor by a controller. The system includes generating adjustments by the controller to cause the stator poles to apply a net radial force to the rotor. This net radial force may be used, for example to cause the rotor to be centered upon a central axis of the electric motor and may be particularly advantageous for a lubricant supported rotor. A motor drive provides an AC current to the stator windings as well as phase current adjustments of the electrical current in one or more of the stator windings to apply the net radial force to the rotor in a direction perpendicular to the drive axis.

A downhole-type system includes a rotatable shaft; a sensor that can sense an axial position of the shaft and generate a first signal corresponding to the axial position of the shaft; a controller coupled to the sensor, in which the controller can receive the first signal generated by the sensor, determine an amount of axial force to apply to the shaft to maintain a target axial position of the shaft, and transmit a second signal corresponding to the determined amount of axial force; and multiple magnetic thrust bearings coupled to the shaft and the controller, in which each magnetic thrust bearing can receive the second signal from the controller and modify a load, corresponding to the second signal, on the shaft to maintain the target axial position of the shaft.