Abstract: This disclosure describes a system for sending control signals and receiving sensor signals over cables at long distances. Electric currents and signals traveling down long cables can undergo phenomenon that are not present in relatively short cables. Therefore, this disclosure contemplates solutions for overcoming or compensating for these phenomenon to enable control of an electric machine using long cables. The solutions can include a signal conditioning circuit, configured to output a DC current corresponding to the sensed voltage associated with the sensor, a first conductor, that transmits the DC current from the signal conditioning circuit to the controller, and a signal generator, configured to receive the command signals and generate pulse width modulated (PWM) actuating signals based on the command signals.

Abstract: An aircraft electric machine includes an electric stator that surrounds and supports a rotor. A housing defines a sealed chamber enclosing the electric stator and is configured to maintain an absolute pressure of a gas within the chamber as an aircraft with the aircraft electric machine changes altitude.

Abstract: The present disclosure describes an apparatus, system, and method of use for detecting electrical faults in a multiphase electric machine. Often in platforms which require redundant reliability or have no readily available electrical connection to earth use ungrounded electrical architectures. This allows the system to continue normal operation even if there is an unintended short circuit or current path (electrical fault) between a phase of an electric machine and its case or some other part of the platform. It is important to be able to readily identify any fault in the phase windings of machinery operating in an ungrounded electrical architecture. Since a single fault in an ungrounded system will not cause any additional current draw or otherwise affect the system, it can be difficult to detect that a fault has even occurred. This provides an advanced warning system.

Abstract: A rotor for an electric machine has a permanent magnet carrier that defines a plurality of permanent magnet receptacles. A plurality of permanent magnets are received in the receptacles. The magnets are arranged to define at least two magnetic poles of the rotor. A metallic shield surrounds an outward facing surface of the permanent magnets to shield the magnets from high frequency magnetic fields that would cause eddy currents, and thus magnet heating. The metallic shield is constructed from a metallic foil. A carbon fiber retaining sleeve surrounds an outward facing surface of the metallic shield. The carbon fiber sleeve is configured to retain the magnets to the permanent magnet carrier during operation of the electric machine. The permanent magnet carrier is interference fit over a rotor core.

Abstract: A rotor for an electric machine includes a central hub with a cylindrical outer surface. A plurality of elongate spacers are affixed to the central hub at its outer surface. The spacers are circumferentially spaced apart from each other and extend axially along the outer surface of the central hub. A plurality of permanent magnets reside on the outer surface between the spacers. The magnets define at least two magnetic poles of the rotor. A metallic shield surrounds an outward facing surface of the permanent magnets and spacers to shield the magnets from high frequency magnetic fields that would cause eddy currents, and thus magnet heating. The metallic shield includes a metallic foil. A carbon fiber retaining sleeve surrounds an outward facing surface of the metallic shield. The carbon fiber sleeve is configured to retain the magnets to the central hub during operation of the electric machine.

Abstract: A rotating machine includes a housing, a rotor shaft to rotate about a longitudinal axis, a position sensor to detect a position of the rotor shaft within the housing, and a magnetic bearing assembly coupled to the housing to support the rotor shaft within the housing. The magnetic bearing assembly includes an active magnetic bearing for active support of the rotor shaft, such as a thrust bearing actuator to produce an axial force component that is parallel to the central longitudinal axis and a radial force component that is orthogonal to the central longitudinal axis and axially offset from the thrust bearing actuator. The magnetic bearing assembly also includes a passive magnetic radial bearing to radially support the rotor shaft within the housing. A controller electrically coupled to the active magnetic bearing controls a control current to the active magnetic bearing.

Abstract: The present disclosure involves a two stage inverter, a system for electrical power conversation, and a method of converting electrical power using silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs). One example implementation includes using two or more SiC MOSFETs in series with each MOSFET having a gate terminal for triggering a state switch between an on (conducting) and off (non-conducting) state of the MOSFET. An AC terminal is connected between the series SiC MOSFETS, and the series SiC MOSFETs are connected across a DC bus and in parallel with one or more capacitors.

Abstract: A first line-to-line terminal voltage of a three-phase electric motor is measured while the three-phase electric motor free-spins. A second line-to-line terminal voltage of a three-phase electric motor is measured while the three-phase electric motor free-spins. A motor's rotor position is determined based on the first line-to-line terminal voltage and the second line-to-line terminal voltage. Three-phase current is sent to the motor after the rotor position has been determined. The three-phase current being in-phase with the rotor position.

Abstract: A first line-to-line terminal voltage of a three-phase electric motor is measured while the three-phase electric motor free-spins. A second line-to-line terminal voltage of a three-phase electric motor is measured while the three-phase electric motor free-spins. A motor's rotor position is determined based on the first line-to-line terminal voltage and the second line-to-line terminal voltage. Three-phase current is sent to the motor after the rotor position has been determined. The three-phase current being in-phase with the rotor position.

Abstract: Noncontact measurements of positions of electrically-conductive objects is achieved by placing two conductive coils formed by traces on printed circuit boards (PCBs) in the proximity of the object surface, energizing one of the coils (excitation coil) with alternating electrical current and measuring the amplitude of the voltage induced on the terminals of the second coil (sensing coil). The alternating magnetic field generated by the current in the excitation coil induces eddy currents in the object, which affect the amplitude of the voltage induced on the terminals of the sensing coil. The sensing coil voltage depends on the mutual position between the object and the sensing coil, allowing the object position measurement. The excitation coil is integrated into a series LCR circuit driven by an output of an adjustable gain amplifier at the resonance frequency. The adjustable amplifier gain is constantly adjusted to maintain the sensor sensitivity constant.

Abstract: A closed loop thermal cycle expander bypass flow control is described. An expander is positioned within and surrounded by a housing to receive a working fluid and rotate in response to expansion of the working fluid flowing through the expander. A bypass channel is positioned within and surrounded by the housing to define a fluid flow path that bypasses the expander. A fluid flow control sub-assembly is fluidically coupled to the expander and the bypass channel, and attached to the housing. The fluid flow control sub-assembly can receive the working fluid at a housing inlet and either flow the working fluid through the expander and block the working fluid from flowing through the bypass channel, or flow the working fluid through the housing bypassing the expander, flow the working fluid out via a housing outlet, and block the working fluid from flowing through the expander.

Abstract: A closed loop thermal cycle expander bypass flow control is described. An expander is positioned within and surrounded by a housing to receive a working fluid and rotate in response to expansion of the working fluid flowing through the expander. A bypass channel is positioned within and surrounded by the housing to define a fluid flow path that bypasses the expander. A fluid flow control sub-assembly is fluidically coupled to the expander and the bypass channel, and attached to the housing. The fluid flow control sub-assembly can receive the working fluid at a housing inlet and either flow the working fluid through the expander and block the working fluid from flowing through the bypass channel, or flow the working fluid through the housing bypassing the expander, flow the working fluid out via a housing outlet, and block the working fluid from flowing through the expander.

Abstract: An electric machine has a stator defining an interior cavity and a rotor supported to rotate in the interior cavity of the stator. The rotor has a rotor core with a plurality of permanent magnets arranged around a perimeter of the rotor core. The magnets define a cylindrical, radially facing outer surface. An electrically conductive shield is provided on and covering the cylindrical outer surface of the permanent magnets. A containment sleeve resides around the rotor core, the permanent magnets and the shield and defines an exterior cylindrical surface of the rotor. The containment sleeve is configured to retain the magnets to the rotor core during operation of the electric machine.

Abstract: A turbocharger system for an engine includes a rotor, a primary bearing system arranged to axially and radially support the rotor to rotate on a central rotational axis, a compressor coupled to a rotor to rotate with the rotor, a turbine coupled to the rotor to rotate with the rotor, and an electromagnetic actuator adjacent to the rotor. The electromagnetic actuator selectively acts on the rotor and supplements the axial support of the primary bearing system by applying a magnetic force on the rotor in a direction parallel to the central rotational axis of the rotor.

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: Radial poles are placed around a radial actuator target mounted on a body. The poles are separated from a cylindrical surface of the target by radial gaps and adapted to communicate a magnetic flux with it. The radial poles are equipped with electrical control windings and magnetically coupled to form magnetic control circuits. A flux return pole is adjacent to the body, separated from it by an air gap and adapted to communicate a magnetic flux with the radial actuator target. A permanent magnet generates a magnetic bias flux in the magnetic bias circuit formed by the radial actuator target, the radial poles and the magnetic flux return pole. A radial force is exerted on the actuator when the control windings are energized with a current. A Hall effect sensor measures bias magnetic field in the air gap between the magnetic flux return pole and the body.

Abstract: Systems, methods, and devices for generating electromagnetic forces may involve generating an axial control magnetic flux in an axial control magnetic circuit comprising a first axial pole, a second axial pole, and an axial actuator target, the axial actuator target coupled to a body having a rotational axis. A radial control flux can be generated in a radial control magnetic circuit comprising a first radial pole, a second radial pole, and a radial actuator target. An electrical compensation current can be applied to an electrical bias flux leveling coil to cancel or nearly cancel any changes of the magnetic flux leaking from either the first or the second axial poles into the radial poles, electrical bias flux leveling coil wound around the rotational axis and located axially between the radial poles and the closest of the first or the second axial poles.

Abstract: The present specification describes systems, methods, and apparatuses for bonding core laminations for electric machines (e.g., stators, actuators, sensors, etc.) using fluoropolymer films. A first metallic lamination can be aligned together with a second metallic lamination with a fluoropolymer in-between. The first and the second metallic laminations can be bonded together with the fluoropolymer. The first and second metallic laminations can be aligned with the fluoropolymer in-between below the melting temperature of the fluoropolymer. The first metallic stator lamination can be clamped to the second metallic stator lamination to fix the relative position. Thereafter, the temperature of the fluoropolymer can be increased above the melting temperature for bonding the first and the second metallic stator laminations.

Abstract: Certain aspects encompass a brushless DC electric machine that has a DC stator having field windings. The DC electric machine additionally has a DC rotor. The DC rotor has a rotor core and a plurality of permanent magnets arranged around the rotor core. The permanent magnets are shaped and have a gap between each adjacent permanent magnet to produce a trapezoidal back EMF in the field windings. A non-magnetic material resides in the gaps and bridges each adjacent permanent magnet. A non-magnetic sleeve is provided around the permanent magnets and the non-magnetic filler material retaining the permanent magnets to the core.

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.