Abstract: An electrical system includes a cycloidal electric machine having a stator and a balanced rotor. The rotor is eccentrically positioned radially within the stator, such that the rotor moves with two degrees of freedom (2DOF). The 2DOF motion includes rotating motion about the rotor axis and orbiting motion about the stator axis. A rotor constraint mechanism constrains the motion of the rotor, such that the rotor is able to generate torque on a coupled load. Part of the rotor constraint mechanism may be integrally formed with the rotor. A coupling mechanism may be coupled to the rotor and configured to translate the 2DOF into 1DOF, i.e., rotation without orbital motion. The rotor may include mutually-coupled rotors. At least one counterweight may be connected to the rotor, e.g., externally or within the airgap. Balancing of the balanced rotor may be optionally provided via the multiple rotors and/or the counterweight(s).

Abstract: A vascular cooled capacitor assembly includes a plurality of capacitors having respective first and second leads, first and second busbars disposed in electrical contact with the first and second leads, an encapsulant enveloping the capacitors and a respective major portion of each of the first and second busbars, and a network of channels enveloped within the encapsulant and formed by deflagration of a sacrificial material. The network has at least one network inlet and at least one network outlet, each of which is configured for sealable engagement with a cooling fluid system. A branch of each channel is positioned inside a central axial passage of a capacitor, around an outer periphery of a capacitor, and/or between two capacitors. A housing may enclose the capacitors, the channels and major portions of the first and second busbars.

Abstract: A method for bonding a polymeric fill material onto a surface of a substrate is described, and includes exposing the surface of the substrate to a microwave-generated argon-hydrogen plasma for a predetermined time period, applying, via a microwave plasma chemical vapor deposition process, a SiOx surface coating onto the surface of the substrate, and executing a post-treatment process to the SiOx surface coating. The polymeric fill material may be applied onto the substrate and subjected to curing.

Abstract: An electric machine is described, and includes a rotor that is rotatably disposed in a stator. The rotor includes a rotatable shaft that is disposed on a longitudinal axis, and a plurality of laminations that are disposed on the rotatable shaft. The plurality of laminations are arranged on the rotatable shaft to form a plurality of axially-disposed cavities, wherein each of the cavities is defined by a surface. A coating is disposed on the surfaces of the cavities, and a curable filler material is introduced into each of the cavities. The curable filler material adheres to the plurality of laminations via the coating.

Abstract: A current command module is configured to, based on a direct current (DC) bus voltage for an electric motor of the vehicle, generate a d-axis current command for the electric motor and a q-axis current command for the electric motor. A voltage command module configured to generate voltage commands based on the d-axis current command and the q-axis current command. A battery switching control module is configured to: determine a voltage operating state of a battery based on the voltage commands; compare a battery parameter to at least one of a predetermined voltage parameter and a predetermined current parameter during a dwell time when a plurality of switches of the battery are open; and generate a switch control signal to transition at least one switch of the plurality of switches to cause the battery to operate in the voltage operating state based on the comparison.

Abstract: Presented are segmented hairpin bar conductors for electric machines, methods for making/using such segmented bar conductors, electromagnetic motors using such segmented bar conductors, and vehicles equipped with an induction motor generator unit using segmented hairpin bar conductors. An electric machine includes a stator that defines multiple circumferentially spaced, radially elongated stator slots. A rotor is located adjacent and movable with respect to the stator. One or more permanent magnets are mounted to the rotor, and one or more U-shaped hairpin windings are mounted to the stator in juxtaposed spaced relation to the magnet(s). Each hairpin winding is formed from an array of collimated, electrically conductive wires that are bundled together into a unitary bar conductor. The segmented hairpin winding has a pair of hairpin legs, each of which adjoins and projects from a respective end of a hairpin crown. Each hairpin leg inserts into a respective one the stator slots.

Abstract: An electrical system includes a power inverter module (PIM) connected to DC and AC voltage buses and having a pair of inverter phase legs, at least one of which includes a plurality of semiconductor switche. A cycloidal electric machine with plurality of electrical phases is connected to the PIM via the AC voltage bus, and has a stator and a rotor with eccentric stator and rotor axes. The rotor moves with two degrees of freedom, including rotating motion about the rotor axis and orbiting motion about the stator axis. A controller applies, for each respective phase, a phase-specific offset value to a carrier signal and to a voltage reference signal. This generates a modified carrier signal and a modified reference signal, respectively, which in turn generate a pulse width modulation (PWM) signal. The electric machine is powered via the PIM by energizing the semiconductor switches using the PWM signal.

Abstract: An axial flux-type rotary electric machine includes a rotor having a rotor axis and a stator having a stator axis. The stator is positioned adjacent to the rotor such that an axial airgap is defined between the rotor and the stator. First and second non-parallel rotor shafts are respectively collinear with the stator axis and the rotor axis. A nutating gear pair is connected to a stationary member and the rotor, and is configured to impart nutating motion to the rotor with respect to the stator, such that a size of the axial airgap changes with a rotational position of the rotor, and such that the rotor has two degrees of freedom of motion. An electrical system includes direct and alternating current voltage buses, a power inverter module connected to the voltage buses, and the axial flux-type rotary electric machine connected to the alternating current voltage bus.

Abstract: An electrical system includes a cycloidal electric machine having a stator and an eccentric rotor. An airgap is defined between the stator and the rotor. The rotor moves with two degrees of freedom (2DOF), including rotating motion about the rotor axis and orbiting motion about the stator axis. A rotor constraint mechanism (RCM) constrains rotor motion to enable output torque to transfer to a coupled load in at least one of the 2DOF. The machine includes a structural element connected to or formed integrally with the rotor or stator that minimizes and substantially equalizes a size of the airgap around a circumference of the rotor. The element may be a crescent-shaped race of ferrous material coupled to a rotor shaft. The stator may include stator teeth, the rotor may include lobes, and the stator teeth and rotor lobes may have cycloid-profiled surfaces that form the structural element.

Abstract: An electrical system includes a power inverter module (PIM) connected to DC and AC voltage buses and having a pair of inverter phase legs, at least one of which includes a plurality of semiconductor switch. A cycloidal electric machine with plurality of electrical phases is connected to the PIM via the AC voltage bus, and has a stator and a rotor with eccentric stator and rotor axes. The rotor moves with two degrees of freedom, including rotating motion about the rotor axis and orbiting motion about the stator axis. A controller applies, for each respective phase, a phase-specific offset value to a carrier signal and to a voltage reference signal. This generates a modified carrier signal and a modified reference signal, respectively, which in turn generate a pulse width modulation (PWM) signal. The electric machine is powered via the PIM by energizing the semiconductor switches using the PWM signal.

Abstract: An electrical system includes a power inverter connected to a battery and outputting a polyphase voltage, and a cycloidal reluctance machine. A machine rotor provides output torque, and is surrounded and separated from the stator by an airgap. The rotor includes permanent magnets providing a fixed-orientation rotor field. The stator includes windings proximate the permanent magnets and electrically connected to the inverter to form stator electromagnets. The rotor field augments the stator field to boost output torque. The rotor is eccentrically positioned with respect to the stator to move with two degrees of freedom (2DOF), including rotating motion and orbiting motion about a center axis of the stator. A rotor constraint mechanism constrains motion of the rotor, such that the rotor is able to generate and transmit the output torque to a coupled load in at least one of the 2DOF.

Abstract: A cycloidal reluctance machine includes a stator surrounding a rotor. Stator windings and rotor windings form respective concentric rotor and stator electromagnets. The rotor is eccentrically positioned with respect to the stator to move with two degrees of freedom (2DOF), including rotating motion about a rotary axis of the rotor and orbiting motion about a center axis of the stator. A rotor constraint mechanism (RCM) constrains motion of the rotor, such that the rotor is able to generate and transmit output torque to a coupled load in at least one of the 2DOF. A magnetic field polarity of stator poles and/or rotor poles of the respective stator and rotor changes over one electrical cycle of the polyphase voltage. The coupled load may be a drive axle of a vehicle in some embodiments. In others, the stator and rotor windings are driven via different power inverters.

Abstract: An electrical system includes a cycloidal electric machine having a stator and an eccentric rotor. An airgap is defined between the stator and the rotor. The rotor moves with two degrees of freedom (2DOF), including rotating motion about the rotor axis and orbiting motion about the stator axis. A rotor constraint mechanism (RCM) constrains rotor motion to enable output torque to transfer to a coupled load in at least one of the 2DOF. The machine includes a structural element connected to or formed integrally with the rotor or stator that minimizes and substantially equalizes a size of the airgap around a circumference of the rotor. The element may be a crescent-shaped race of ferrous material coupled to a rotor shaft. The stator may include stator teeth, the rotor may include lobes, and the stator teeth and rotor lobes may have cycloid-profiled surfaces that form the structural element.

Abstract: A rotary electric machine, e.g., a cycloidal reluctance motor, includes a stator having stator teeth connected to a cylindrical stator core, and a rotor having a cylindrical rotor core. The stator core and/or rotor core are constructed of grain-oriented, spirally-wound ferrous material having a circular or annular grain orientation. The stator teeth may be constructed of grain-oriented steel having a linear grain orientation. Notches may be spaced around an inner circumferential surface of the stator core, with each stator tooth engaged with a respective notch. The rotor may be eccentrically positioned radially within the stator. The rotor core may define notches spaced around its outer circumferential surface, with salient rotor projections engaged with a respective rotor notch. The machine in such an embodiment may be a switched reluctance rotor. An electrical system using the machine and a method of manufacturing the machine are also disclosed.

Abstract: An electrical system includes a power inverter connected to a battery and outputting a polyphase voltage, and a cycloidal reluctance machine. A machine rotor provides output torque, and is surrounded and separated from the stator by an airgap. The rotor includes permanent magnets providing a fixed-orientation rotor field. The stator includes windings proximate the permanent magnets and electrically connected to the inverter to form stator electromagnets. The rotor field augments the stator field to boost output torque. The rotor is eccentrically positioned with respect to the stator to move with two degrees of freedom (2 DOF), including rotating motion and orbiting motion about a center axis of the stator. A rotor constraint mechanism constrains motion of the rotor, such that the rotor is able to generate and transmit the output torque to a coupled load in at least one of the 2 DOF.

Abstract: A cycloidal reluctance machine includes a stator surrounding a rotor. Stator windings and rotor windings form respective concentric rotor and stator electromagnets. The rotor is eccentrically positioned with respect to the stator to move with two degrees of freedom (2DOF), including rotating motion about a rotary axis of the rotor and orbiting motion about a center axis of the stator. A rotor constraint mechanism (RCM) constrains motion of the rotor, such that the rotor is able to generate and transmit output torque to a coupled load in at least one of the 2DOF. A magnetic field polarity of stator poles and/or rotor poles of the respective stator and rotor changes over one electrical cycle of the polyphase voltage. The coupled load may be a drive axle of a vehicle in some embodiments. In others, the stator and rotor windings are driven via different power inverters.

Abstract: An electrical system includes a cycloidal electric machine having a stator and a balanced rotor. The rotor is eccentrically positioned radially within the stator, such that the rotor moves with two degrees of freedom (2DOF). The 2DOF motion includes rotating motion about the rotor axis and orbiting motion about the stator axis. A rotor constraint mechanism constrains the motion of the rotor, such that the rotor is able to generate torque on a coupled load. Part of the rotor constraint mechanism may be integrally formed with the rotor. A coupling mechanism may be coupled to the rotor and configured to translate the 2DOF into 1DOF, i.e., rotation without orbital motion. The rotor may include mutually-coupled rotors. At least one counterweight may be connected to the rotor, e.g., externally or within the airgap. Balancing of the balanced rotor may be optionally provided via the multiple rotors and/or the counterweight(s).

Abstract: An electrical system includes an inverter connected to AC and DC voltage buses, a cycloidal electric machine connected to the PIM via the AC voltage bus, and a controller. The machine's rotor is eccentric with respect to the stator, an airgap between the stator and rotor is smaller at an instantaneous center of rotation of the rotor than elsewhere around a circumference of the rotor, and the rotor moves with two degrees of freedom (2DOF), i.e., rotating and orbiting motion. The controller receives a torque command, the rotor position signal, and the current signals, and in response identifies an optimal stator pole or pole pair located proximate the instantaneous center of rotation and energizes the optimal stator pole or pole pair via the PIM prior to energizing another stator pole or pole pair of the stator.

Abstract: A fluid-cooled axial flux motor having a stator, a rotor disposed adjacent to the stator, and a rotor shaft rotationally fixed onto the rotor. The rotor shaft includes axial coolant passageway having an inlet and opposite outlet. The rotor includes coolant passageways extending radially from rotor shaft. The rotor coolant passageways include an inlet in fluid communication with the outlet of the axial coolant passageway and an outlet. The fluid-cooled axial flux motor further includes a coolant distribution header having an inlet in fluid communication with the outlet of the rotor coolant passageway, a coolant collection header having an inlet in fluid communication with the outlet of the coolant distribution header, and a collection header outlet. The outlet of the coolant distribution header is disposed above the stator and the inlet of the coolant collection header is disposed below the stator with respect to the direction of gravity.

Abstract: In one example implementation according to aspects of the present disclosure, a DC-to-DC converter for transmitting electricity from a first power device at a first voltage and current combination to a second power device at a second voltage and current combination is provided. The DC-to-DC converter comprises a first electrical conductor having a first end and a second end and a second electrical conductor having a third end and a fourth end. The first end and the third end are electrically coupled to the first power device and the second end and the fourth end are electrically coupled to the second power device. The first electrical conductor and the second electrical conductor together provide circuit inductance substantially equivalent to and in place of an inductor having a circular winding.