Abstract: The present disclosure describes a mechanical backup bearing system arrangement to work in conjunction with non-contact magnetic bearings and capable of coping with thermal expansions of the bearing components during operations. Expansions or contractions of an inner or outer race of a bearing can be compensated using particular springs providing a low profile and a proper stiffness. An electric machine system includes a rotational portion and a stationary portion. The electric machine further includes a magnetic bearing configured to support the rotational portion to rotate within the stationary portion. A mechanical back-up bearing resides in a cavity between the rotational portion and the stationary portion. A flat spring is carried by the stationary portion and abutting the back-up bearing.

Abstract: This disclosure relates to diagnosing a power electronic device by itself and extending the diagnostics to an electric machine coupled with the power electronic device and deployed at an operational site. The power electronic device can power and control the electric machine. The diagnostics can include testing the status of the power electronic device, and monitoring hardware changes in the electric machine. The diagnostics can be performed within the power electronic device on demand, periodically, or both. In some instances, the self-diagnostics can evaluate whether components are defective or wired incorrectly, characterized by wrong inductance, and/or resistance, for example. In some implementations, the power electronic device includes a digital signal processing unit for the self-diagnostics and a data record system for recording and troubleshooting errors related to load performance and/or parameters.

Abstract: A first bias magnetic flux may be communicated between a first axial pole and a first axial facing surface of the body. A second bias magnetic flux may be communicated between a second axial pole and a second axial facing surface of the body. A time-varying axial control magnetic flux may be communicated through the first and second axial facing surfaces of the body, and may be generated in a magnetic circuit including the body, the first and second axial poles, and an axial magnetic backiron. The first and second axial poles may include axial pole laminated inserts composed of electrically isolated steel laminations stacked along the body axis. The axial magnetic backiron may include laminated inserts composed of electrically isolated steel laminations stacked in the direction tangential to the body axis. The axial pole laminated inserts may be magnetically coupled to the axial magnetic backiron laminated inserts.

Abstract: An electromagnetic actuator can exert a radial electromagnetic force on a body that is configured to rotate about a rotational axis. The actuator includes a radial control magnetic pole assembly that includes radial control poles adjacent to and spaced apart by air gaps from the body. The actuator includes a permanent magnet (PM) magnetized along the axis, having one pole in contact with an axial face of the assembly and located proximate to a lateral surface of the body. The PM is magnetically coupled to the body in a non-contact manner resulting in a bias magnetic flux in the air gaps. The actuator includes a control coil around the radial control poles located radially outwards from the PM. Electrical current in the coils generates control magnetic flux in air gaps. The non-uniform net magnetic flux distribution around the body results in a radial electromagnetic force exerted on the body.

Abstract: A machine includes a rotor supported to rotate about a rotational axis and an actuator arranged to act on the rotor and control a position of the rotor about the rotational axis. A bladed turbomachine wheel is coupled to the rotor and has blade tips that pass closely to an adjacent, non-rotating surface. A sensor is adjacent to the turbomachine wheel and arranged to sense the blade tips and output a position signal representative of the position of blade tips relative to the sensor. A controller is coupled to the sensor and the actuator and is adapted to receive the position signal from the sensor and generate and send a control signal to the actuator to control the position of the rotor based on the position signal from the sensor.

Abstract: An electromagnetic actuator includes a body and first and second poles residing apart from the body. The first and second poles communicate magnetic flux across a gap with opposing end facing surfaces of the body. The body, the first pole, and the second pole are magnetically coupled and define an axial magnetic control circuit. A plurality of radial poles reside apart from the body, adjacent a lateral facing surface of the body, and communicate magnetic fluxes with the lateral facing surface. The body and the plurality of radial poles define a plurality of radial magnetic control circuits. The plurality of radial poles communicate magnetic fluxes with the lateral facing surface and at least one of the first pole or the second pole, and the body, the plurality of radial poles, and at least one of the first pole or the second pole define a magnetic bias circuit.

Abstract: Noncontact measuring of positions of objects is achieved through measurements of parameters characterized by the distribution of an AC magnetic flux in the air gap between stationary and moveable portions defining a sensor magnetic circuit. A sensor head fixed relative to a stationary element includes a soft-magnetic core. A sensor target is fixed relative to a movable element, the soft-magnetic core and the sensor target separated by an air gap and defining a magnetic circuit. A coil around the soft-magnetic core is adapted to produce a magnetic flux in the magnetic circuit. A magnetic flux density sensor fixed relative to the sensor head resides in the gap between the soft-magnetic core and the sensor target and is configured to detect magnetic flux density in a portion of the gap. A controller in communication with the magnetic flux density sensor is configured to receive an output signal of the magnetic flux.

Abstract: A body is equipped with magnetically connected radial and axial actuator targets. The radial actuator target features a cylindrical lateral surface. The axial actuator target features the first and the second end-facing surfaces. A radial pole is adapted to communicate a magnetic flux with the cylindrical lateral surface. Magnetically connected first and second axial poles are located axially on one side of the radial pole and adapted to communicate magnetic fluxes with the first and the second end-facing surfaces. The first axial pole, the second axial pole and the axial actuator target form a magnetic axial control circuit. The radial pole, the radial actuator target, the axial actuator target, the first axial pole and the second axial pole form the magnetic bias circuit. Superposition of magnetic fluxes in the axial control circuit and in the bias circuit results in an axial force acting on the axial actuator target.

Abstract: An electrical machine having a centrifugal compressor for producing a fluid flow to cool one or more portions thereof. In one embodiment, the fluid is separated into separate flows, each of the flows flowing through only a portion of an annular gap formed between a rotor and stator of the electrical machine. According to some embodiments, the centrifugal compressor pushes a fluid through the electrical machine, whereas, in other embodiments, the centrifugal compressor pulls the fluid through the electrical machine. The centrifugal compressor includes an impeller that is attached to a shaft of the rotor. According to other embodiments, the electrical machine may include longitudinal channels formed between a housing of the electrical machine and the stator. A first flow of the fluid travels through the annular gap, and a second flow travels through the longitudinal channels. The electrical machine may also include a damper disposed in the longitudinal channels.

Abstract: An apparatus includes an electric generator having a stator and a rotor. A turbine is coupled to an end of the rotor to rotate at the same speed as the rotor. The turbine may rotate in response to expansion of a working fluid flowing from an inlet side to an outlet side of the turbine. The apparatus also includes a housing assembly with an inwardly oriented shroud, which is located at close proximity to the turbine. The proximity of the shroud to the turbine establishes the pressure ratio of the turbine, allowing the system to operate without seals. Magnetic bearings and position sensors are used to maintain the distance between the shroud and the wheel. In certain implementations, the positioning of the turbine can be controlled to optimize machine performance.

Abstract: An electromagnetic actuator generates electromagnetic forces across large radial gaps to support a body. The actuator has an actuator target having a rotational axis, and a target magnetic element arranged circumferentially around the rotational axis that has inner and outer magnetic poles. A cylindrical soft-magnetic target pole is magnetically coupled to the outer cylindrical magnetic pole of the target magnetic element. An actuator base includes radial poles arranged circumferentially around and radially spaced apart from the cylindrical soft-magnetic target pole. The radial poles and the cylindrical soft-magnetic target pole are magnetically coupled and define a plurality of magnetic control circuits. Control coils around the radial poles are configured to produce magnetic fluxes in the magnetic control circuits.

Abstract: A body is equipped with magnetically connected radial and axial actuator targets. The radial actuator target features a cylindrical lateral surface. The axial actuator target features the first and the second end-facing surfaces. A radial pole is adapted to communicate a magnetic flux with the cylindrical lateral surface. Magnetically connected first and second axial poles are located axially on one side of the radial pole and adapted to communicate magnetic fluxes with the first and the second end-facing surfaces. The first axial pole, the second axial pole and the axial actuator target form a magnetic axial control circuit. The radial pole, the radial actuator target, the axial actuator target, the first axial pole and the second axial pole form the magnetic bias circuit. Superposition of magnetic fluxes in the axial control circuit and in the bias circuit results in an axial force acting on the axial actuator target.

Abstract: A fluid pumping and energy recovery device may include a housing that defines an impeller chamber and a motor/generator chamber. An impeller may reside within the impeller chamber; and a motor/generator may reside in the motor/generator chamber. The motor/generator may include a stator and a rotor. The rotor may be coupled to the impeller and supported (e.g., by magnetic bearings) to rotate in the stator. The rotor may generate electrical power in a generating mode and rotate in response to electrical power applied to the stator in a motoring mode. Seals may be adapted to hydraulically isolate the pump chamber from the motor/generator chamber by sealing against a rotating surface of the device. In certain instances, sealing is achieved using a bidirectional seal.

Abstract: An apparatus for measuring linear velocity of a movable element relative to a stationary element includes a magnetic element fixed in relation to the stationary element. A soft-magnetic yoke is fixed in relation to the movable element to move with the movable element and is in non-contact relation with the magnetic element. A yoke pole is positioned proximate to the magnetic element and spaced therefrom by an air gap. The pole is magnetically coupled to the magnetic element so that a magnetic flux is generated in the air gap substantially orthogonal to the axis of motion. A conductive coil is coiled around a coil axis and is fixed in relation to the stationary element with the coil axis substantially parallel to the axis of movement. The coil is in non-contact relation with the yoke and resides between the magnetic element and the pole of the yoke in the magnetic flux.

Abstract: A homopolar magnetic actuator is configured to exert controllable radial forces on a body adapted to rotate around an axis. The actuator comprises at least three radial magnetic pole assemblies distributed at some distances from each other along the axis, each including a plurality of poles adjacent to an actuator target on the body. Permanent magnets are used to induce bias magnetic fluxes in the assemblies with polarities alternating from assembly to assembly but remaining the same around the rotational axis. Having several small bias fluxes distributed between several pole assemblies instead of a large single bias flux facilitates designing an actuator with a high aspect ratio. A control coil around each pole can induce a control magnetic flux in the poles. These control fluxes affect magnetic flux distribution around the actuator target, resulting in magnetic forces exerted on the target.

Abstract: An electromagnetic actuator with flux feedback control includes two poles located on opposite sides of a soft-magnetic target. A bias flux is introduced that flows into both poles. Magnetic circuitry may be designed so that the total bias flux is independent or substantially independent of a position of the target with respect to the poles or the control flux. The electromagnetic actuator also includes flux sensors introduced into each gap between the poles and the target. The electromagnetic actuator further includes an actuator control circuit to command the current in the control coil to bring a difference between the readings of the two flux sensors to a targeted level. In some aspects, the force exerted on the actuator target in this arrangement may be proportional to the command signal regardless of the position of the actuator target, MMF drop in the soft-magnetic parts of the magnetic circuit, or the frequency.

Abstract: An apparatus includes an electric generator having a stator and a rotor. A turbine is coupled to an end of the rotor to rotate at the same speed as the rotor. The turbine may rotate in response to expansion of a working fluid flowing from an inlet side to an outlet side of the turbine. The apparatus also includes a housing assembly with an inwardly oriented shroud, which is located at close proximity to the turbine. The proximity of the shroud to the turbine establishes the pressure ratio of the turbine, allowing the system to operate without seals. Magnetic bearings and position sensors are used to maintain the distance between the shroud and the wheel. In certain implementations, the positioning of the turbine can be controlled to optimize machine performance.

Abstract: An apparatus includes an electric generator having a stator and a rotor. A first turbine wheel is coupled to a first end of the rotor to rotate at the same speed as the rotor. A second turbine wheel is coupled to a second end of the rotor opposite the first end, and configured to rotate at the same speed as the rotor. The first and second turbine wheels may rotate in response to expansion of a working fluid flowing from an inlet side to an outlet side of the turbine wheels.

Abstract: A turbine wheel is rotatable in response to expansion of a working fluid flowing from near an inlet side towards an outlet side of the turbine wheel. The turbine wheel may receive the working fluid radially into the inlet side of the turbine wheel and output the working fluid axially from its outlet side. A generator has a stator and a rotor. The rotor may be coupled to the turbine wheel and may rotate at the same speed as the turbine wheel when the turbine wheel rotates. In certain instances, the generator is adjacent the inlet side of the turbine wheel.

Abstract: An electrical machine having a centrifugal compressor for producing a fluid flow to cool one or more portions thereof. In one embodiment, the fluid is separated into separate flows, each of the flows flowing through only a portion of an annular gap formed between a rotor and stator of the electrical machine. According to some embodiments, the centrifugal compressor pushes a fluid through the electrical machine, whereas, in other embodiments, the centrifugal compressor pulls the fluid through the electrical machine. The centrifugal compressor includes an impeller that is attached to a shaft of the rotor. According to other embodiments, the electrical machine may include longitudinal channels formed between a housing of the electrical machine and the stator. A first flow of the fluid travels through the annular gap, and a second flow travels through the longitudinal channels. The electrical machine may also include a damper disposed in the longitudinal channels.