Patents by Inventor Thomas W. Nehl

Thomas W. Nehl has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20220037944
    Abstract: A method for constructing a lamination for a rotary electric machine includes forming an annular lamination from a ferrous core material having a first relative magnetic permeability. The lamination defines through-openings, e.g., for permanent magnets or conductors. Peripheral bridges of the core material extend between the through-openings and an outer or inner diameter surface of the lamination. The method includes diffusing an alloy material having a second relative magnetic permeability into the bridges to form austenitic bridges, with the second relative magnetic permeability being less than the first relative magnetic permeability. A rotary electric machine includes a stator and rotor. A vehicle includes a rotary electric machine connected to the battery pack and to road wheels, and having a rotor and/or a stator constructed in accordance with the method.
    Type: Application
    Filed: July 31, 2020
    Publication date: February 3, 2022
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Alireza Fatemi, Anil K. Sachdev, Thomas W. Nehl
  • Publication number: 20210402887
    Abstract: A method of controlling fast charging of at least one battery pack within a high voltage electrical propulsion system includes identifying an operating condition, wherein the operating condition is one of charging mode and propulsion mode, and, when the electrical system is in charging mode, initiating charging of the at least one battery pack, terminating charging of the at least one battery pack and connecting the at least one battery pack to power components of the electrical propulsion system when there is a request to terminate charging of the at least one battery pack, and terminating charging of the at least one battery pack and connecting the at least one battery pack to power components of the electrical propulsion system when there is no request to terminate charging of the at least one battery pack and the charging of the at least one battery pack is complete.
    Type: Application
    Filed: June 29, 2020
    Publication date: December 30, 2021
    Inventors: Rashmi Prasad, Chandra S. Namuduri, Suresh Gopalakrishnan, Thomas W. Nehl
  • Publication number: 20210344187
    Abstract: A disconnect device includes a mounting plate having a thermally conductive substrate applied onto the mounting plate. A first layer of an electrically conductive material is applied onto the substrate. A semiconductor switch supported on the first layer connects or disconnects an input power source to or from a load. A second layer of an electrically conductive material applied onto the substrate is electrically isolated from the first layer. An electronic sensing, control and protection circuit is supported on the second layer and is connected to the semiconductor switch to control operation of the semiconductor switch. A control unit in communication with the electronic sensing, control and protection circuit via an electrically isolated control path provides control and communication between the electronic sensing, control and protection circuit and the semiconductor switch.
    Type: Application
    Filed: April 30, 2020
    Publication date: November 4, 2021
    Inventors: Chandra S. Namuduri, Rashmi Prasad, Thomas W. Nehl, David J. Brooks
  • Publication number: 20210237587
    Abstract: A modular drive system includes a first motor and a second motor. The first motor generates a first torque over a first torque bandwidth, and has a first stator, a first rotor, and a first winding. The first winding has a first number of turns, a first conductor area and a first insulation suitable for a first peak voltage of the first motor. The second motor generates the first torque over a second torque bandwidth, and has a second stator matching the first stator, a second rotor matching the first rotor and a second winding. The second winding has the first number of turns, the first conductor area and a second insulation suitable for a second peak voltage of the second motor. The second peak voltage is greater than the first peak voltage. The second torque bandwidth is wider than the first torque bandwidth.
    Type: Application
    Filed: February 5, 2020
    Publication date: August 5, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Thomas W. Nehl, Alireza Fatemi, Chandra S. Namuduri
  • Publication number: 20210234447
    Abstract: An electric machine includes a machine rotor circumscribed by a machine stator, and having a rotor shaft, rotor stack, and end cap which rotate about an axis. The end cap includes lobes equal in number to a number of pole pairs of the machine rotor. A position sensor assembly has a predetermined alignment with the machine rotor and stator. The sensor assembly includes a sensor rotor formed by the lobes and a sensor stator having a printed circuit board with conductive sine and cosine traces. Machine rotor rotation causes the sensor assembly to output an unmodulated sine and cosine signals to a controller, which then calculates a calibrated reference angle. A magnetic axis of an electrical phase of the machine is aligned with and bisects a peak of the sine trace. A direct axis of the machine rotor aligns with an edge of a lobe.
    Type: Application
    Filed: January 28, 2020
    Publication date: July 29, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Suresh Gopalakrishnan, Chandra S. Namuduri, Alexandru Rajala, Thomas W. Nehl, Xiaohui Du, Edward L. Kaiser
  • Patent number: 11056991
    Abstract: A method and system for controlling and regulating operation of a multi-phase rotary electric machine in a manner that minimizes power loss under partial load conditions is described. This includes an instruction set that is executable to determine a torque command and a rotational speed of the electric machine, determine a peak torque per loss parameter for the electric machine based upon the rotational speed, and determine a second torque parameter for the electric machine based upon the rotational speed. A modulated torque command for controlling the electric machine is determined based upon the peak torque per loss parameter and the second torque parameter, wherein the electric machine generates an average torque that is equivalent to the torque command when operating in response to the modulated torque command. The inverter is controlled to operate the electric machine based upon the modulated torque command.
    Type: Grant
    Filed: November 22, 2019
    Date of Patent: July 6, 2021
    Assignee: GM Global Technology Operations LLC
    Inventors: Alireza Fatemi, Thomas W. Nehl
  • Patent number: 11043875
    Abstract: An apparatus for cooling an electric machine includes a plurality of fluid channels disposed in a first surface that surrounds at least part of the electric machine. Each of the plurality of fluid channels defines a circumferential path in the first surface, including a first channel section extending at least substantially parallel to first and second circumferences defined by ends of the electric machine, and including a second channel section configured to direct a cooling fluid between a central region of the first surface and an end region of the first surface. The apparatus also includes an outer shell configured to surround the first surface and define a fluid tight chamber between the first surface and the outer shell, the outer shell having at least one inlet through which the cooling fluid is introduced into the chamber and at least one outlet from which the cooling fluid exits the volume.
    Type: Grant
    Filed: November 20, 2018
    Date of Patent: June 22, 2021
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Alireza Fatemi, Xiaofeng Yang, Thomas W. Nehl, Farzad Samie, Srihari K. Gangaraj
  • Publication number: 20210159826
    Abstract: A method and system for controlling and regulating operation of a multi-phase rotary electric machine in a manner that minimizes power loss under partial load conditions is described. This includes an instruction set that is executable to determine a torque command and a rotational speed of the electric machine, determine a peak torque per loss parameter for the electric machine based upon the rotational speed, and determine a second torque parameter for the electric machine based upon the rotational speed. A modulated torque command for controlling the electric machine is determined based upon the peak torque per loss parameter and the second torque parameter, wherein the electric machine generates an average torque that is equivalent to the torque command when operating in response to the modulated torque command. The inverter is controlled to operate the electric machine based upon the modulated torque command.
    Type: Application
    Filed: November 22, 2019
    Publication date: May 27, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Alireza Fatemi, Thomas W. Nehl
  • Patent number: 11015564
    Abstract: A starter assembly includes a multi-phase brushless electric motor including a stator, a rotor disposed on a rotatable shaft, and a motor endcap disposed at a first end of the stator. An electronic commutator assembly includes a sensing circuit, a control electronics subassembly, a power electronics subassembly and a heat sink. The sensing circuit is disposed adjacent to the second end of the rotatable shaft. The control electronics subassembly, the power electronics subassembly and the heat sink are disposed on disk-shaped devices arranged in a stacked configuration orthogonal to the axis defined by the rotatable shaft. The control electronics subassembly is disposed adjacent to the sensing circuit, and the power electronics subassembly is disposed adjacent to the control electronics subassembly. The control electronics subassembly is interposed between the power electronics subassembly and the sensing circuit. The heat sink is disposed adjacent to the power electronics subassembly.
    Type: Grant
    Filed: April 24, 2018
    Date of Patent: May 25, 2021
    Assignee: GM Global Technology Operations LLC
    Inventors: Chandra S. Namuduri, Lei Hao, Alexandru Rajala, Thomas W. Nehl
  • Publication number: 20210143693
    Abstract: A rotary electric machine includes a rotor assembly, stator, stator windings, and a coolant manifold. The rotor assembly includes a rotor and a rotor shaft. The stator is spaced apart from the rotor by a stator-rotor airgap and has stator teeth defining enclosed stator slots. Distal ends of adjacent stator teeth are joined together or integrally formed such that the enclosed stator slots are not contiguous with the airgap. The stator windings constructed from hairpin or bar-type conductors extend axially through the stator within the enclosed stator slots. The coolant manifold is in fluid communication with a coolant supply and configured to seal against an axial end surface of the stator to enclose a portion of the stator windings. The manifold receives and directs coolant from the coolant supply into the enclosed stator slots through the axial end surface to cool the stator via forced convection.
    Type: Application
    Filed: November 8, 2019
    Publication date: May 13, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Thomas W. Nehl, Farzad Samie, Alireza Fatemi, Derek F. Lahr, Tito R. Huffman
  • Publication number: 20210099034
    Abstract: A modular stator-inverter assembly for an electric machine includes a stator and a traction power inverter module (“TPIM”). The stator includes a stator core having a center axis, an inner diameter (“ID”), an outer diameter (“OD”), and electrical conductors forming stator windings. Stator teeth extending radially toward the center axis from the ID collectively define stator slots occupied by the stator windings. Each adjacent pair of stator teeth defines a respective stator slot. The TPIM delivers a polyphase voltage to the stator windings to generate a predetermined number of stator poles, such that the stator has either two, three, or four of the stator slots per electric phase per stator pole. The stator defines a center cavity and is configured to receive a selected rotor from an inventory of preconfigured machine rotors. The inventory includes multiple synchronous reluctance machine rotors and an induction machine rotor.
    Type: Application
    Filed: October 1, 2019
    Publication date: April 1, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Alireza Fatemi, Thomas W. Nehl
  • Patent number: 10940771
    Abstract: An electric propulsion system includes a polyphase rotary electric machine that imparts motor torque to a load, a traction power inverter module (“TPIM”) connected to the electric machine, a reconfigurable energy storage system (“RESS”) connected to the TPIM, and a controller. The RESS has multiple battery modules and a switching circuit. The battery modules are connectable in a series-connected (“P-connected”) configuration at a first/low battery voltage level, and a series-connected (“S-connected”) configuration at a second/high battery voltage level that exceeds the first voltage. The controller determines power losses of the electric propulsion system at the first and second battery voltage levels, receives a commanded output torque and output speed of the electric machine, and selects the S-connected or P-connected configuration based on the predetermined power loss and commanded output torque and speed.
    Type: Grant
    Filed: October 17, 2019
    Date of Patent: March 9, 2021
    Assignee: GM Global Technology Operations LLC
    Inventors: Alireza Fatemi, Thomas W. Nehl, Chandra S. Namuduri, Lei Hao, Norman K. Bucknor
  • Patent number: 10923287
    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.
    Type: Grant
    Filed: August 6, 2019
    Date of Patent: February 16, 2021
    Assignee: GM Global Technology Operations LLC
    Inventors: Anthony M. Coppola, Alireza Fatemi, Thomas W. Nehl
  • Patent number: 10923969
    Abstract: Systems, methods and motor-generators with preform windings and a molded core are described. The preform windings include a first end, a second end, and a plurality of in-slot portions extending from the first end to the second end. The molded core includes a plurality of slots. Each of the plurality of slots including a respective in-slot portion disposed therein. Each of the plurality of slots includes a wall conforming to an outer profile of the respective in-slot portion.
    Type: Grant
    Filed: January 14, 2019
    Date of Patent: February 16, 2021
    Assignee: GM Global Technology Operations LLC
    Inventors: Alireza Fatemi, Anthony M. Coppola, Thomas W. Nehl, David J. Brooks
  • Publication number: 20210043389
    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.
    Type: Application
    Filed: August 6, 2019
    Publication date: February 11, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Anthony M. Coppola, Alireza Fatemi, Thomas W. Nehl
  • Publication number: 20210036643
    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.
    Type: Application
    Filed: July 31, 2019
    Publication date: February 4, 2021
    Inventors: Yue-Yun WANG, Lei HAO, Alireza FATEMI, Thomas W. NEHL, Chandra S. NAMUDURI
  • Patent number: 10900458
    Abstract: A method of stopping an engine crankshaft includes selecting a target angular position at which the engine crankshaft is to be stopped and detecting an actual angular position of the engine crankshaft and a rotational speed of the engine crankshaft. A stopping torque in calculated based on the actual angular position of the engine crankshaft and the rotational speed of the engine crankshaft. The stopping torque is applied to the engine crankshaft via a motor/generator operably connected to the engine crankshaft. The engine crankshaft is stopped at the target angular position via the application of the stopping torque.
    Type: Grant
    Filed: May 8, 2019
    Date of Patent: January 26, 2021
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Suresh Gopalakrishnan, Paul S. Lombardo, David W. Walters, Chunhao J. Lee, Chandra S. Namuduri, Neeraj S. Shidore, Thomas W. Nehl
  • Publication number: 20210006115
    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.
    Type: Application
    Filed: July 2, 2019
    Publication date: January 7, 2021
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Thomas W. Nehl, Alireza Fatemi
  • Patent number: 10886817
    Abstract: A starter assembly includes a partial planetary gear set connected to a pinion gear slidable along a first axis. The starter also includes a motor casing housing a brushless electric motor and having a first bearing. The motor includes multi-phase stator and rotor assemblies arranged inside the casing concentrically relative to the first axis. The rotor assembly has a rotor with a shaft supported by the first bearing and connected to a sun gear engaging the gear set, and a rotor position and speed sensor target. The starter additionally includes a motor end-cap for mating with and enclosing the motor casing and having a second bearing supporting the shaft. The starter also includes an electronics cover with a power connector for mating with the end-cap and housing an electronic commutator assembly. The commutator assembly includes power electronics, and control processor electronics arranged between the end-cap and the power electronics.
    Type: Grant
    Filed: April 24, 2018
    Date of Patent: January 5, 2021
    Assignee: GM Global Technology Operations LLC
    Inventors: Chandra S. Namuduri, Lei Hao, Alexandru Rajala, Thomas W. Nehl
  • Patent number: 10854933
    Abstract: Presented are battery pack voltage-switching (“V-switch”) systems, methods for making/operating such systems, and multi-pack, electric-drive motor vehicles with battery pack V-switch capabilities. A method for controlling operation of a vehicle includes a vehicle controller receiving a voltage switch signal to change a voltage output of the vehicle's battery system. The vehicle controller determines if a speed of a traction motor is less than a calibrated base speed; if so, the controller transmits a pack isolation signal to a power inverter to electrically disconnect the traction battery packs from the traction motor. The vehicle controller determines if a bus current of a DC bus is less than a calibrated bus current threshold; if so, the controller transmits an open signal to open one or more pack contactor switches and a close signal to close one or more pack contactor switches thereby causing the vehicle battery system to output the second voltage.
    Type: Grant
    Filed: January 18, 2019
    Date of Patent: December 1, 2020
    Assignee: GM Global Technology Operations LLC
    Inventors: Lei Hao, Yue-Yun Wang, Chandra S. Namuduri, Suresh Gopalakrishnan, Thomas W. Nehl, Dongxu Li