Patents by Inventor Alireza Fatemi

Alireza Fatemi 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).

  • Patent number: 11621621
    Abstract: An axial flux motor includes: a stator having a first side and a second side opposite the first side, the stator including: N stator core components on the first side, where N is an integer greater than two; and pole shoes attached to radial sides of the N stator core components, N slot openings between adjacent ones of the pole shoes, where each of the N slot openings extends in at least one direction non-radially on the first side; and a rotor including a third side and M permanent magnets on the third side, where the first side is parallel to the third side, and where M is an integer greater than two.
    Type: Grant
    Filed: October 27, 2020
    Date of Patent: April 4, 2023
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Jian Yao, Chengwu Duan, Yusheng Zou, Alireza Fatemi
  • Publication number: 20230070394
    Abstract: Rotor for electric machines and methods for fabricating rotors for electric machines are provided. An exemplary method includes assembling a stack of laminations to form a rotor core having an external surface. The rotor core defines one to five layers of internal cavities and an interior permanent magnet is positioned in a selected internal cavity. The method also includes locating a non-magnetic structural element in the selected internal cavity. Further, the method includes applying a compressive force on the external surface of the rotor core with an annular sleeve.
    Type: Application
    Filed: August 24, 2021
    Publication date: March 9, 2023
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Alireza Fatemi, Anthony M. Coppola, Derek F. Lahr, Alan G. Holmes
  • Publication number: 20230054794
    Abstract: A stator assembly for an electric machine includes stator teeth connected to a stator yoke to form a stator core. Adjacent teeth define a stator slot. Stator windings are disposed within the slot. A molding material fills the slot around the windings, providing a desired thermoelectrical performance level at different slot regions, including electrical insulation, thermal conductivity, and/or electrostatic shielding levels. A method insulates the stator assembly by inserting a molding tool(s) into the slot to define a void volume, filling the void volume with the dielectric molding material, and curing the dielectric molding material to form a slot liner layer adjacent to the tooth walls. A slot opening between adjacent teeth is filled with an electrically-conductive resin to form an electrostatic shielding layer. An electrical system includes an AC voltage bus connected to a power inverter module and to the electric machine having the above-described stator assembly.
    Type: Application
    Filed: August 18, 2021
    Publication date: February 23, 2023
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Alireza Fatemi, Anthony M. Coppola, Farzad Samie, Thomas W. Nehl
  • Publication number: 20230053482
    Abstract: A rotor lamination for an electric machine includes a body having a first axial surface, a second axial surface, a central opening, and an outer annular edge defining a radius. A plurality of magnet receiving openings are formed in the body. Each of the plurality of magnet receiving openings includes a first magnet receiving portion and a second magnet receiving portion. A composite insert is mounted in the body. The composite insert extending along the radius across the magnet receiving opening physically separating the first magnet receiving portion from the second magnet receiving portion.
    Type: Application
    Filed: August 23, 2021
    Publication date: February 23, 2023
    Inventors: Derek Frei Lahr, Anthony Michael Coppola, Alireza Fatemi
  • Publication number: 20230045291
    Abstract: A rotor core for an electric machine of an automobile includes a core stack including a plurality of lamination plates. Each lamination plate includes a plurality of apertures formed therein. The plurality of apertures of each of the lamination plates are axially aligned and define and a slot extending through the core stack and shaped to receive a corresponding insert. The rotor core also includes at least one insert received by the slot that provides radial structural stability to the plurality of lamination plates to prevent portions of the plurality of lamination plates adjacent the plurality of magnet slots from flexing due to radial forces exerted on the plurality of lamination plates during operation of the rotor core. The rotor core includes a load bearing polymer disposed within the aperture of the rotor core that provides contact between and the insert and the lamination plates.
    Type: Application
    Filed: August 3, 2021
    Publication date: February 9, 2023
    Inventors: Derek Frei Lahr, Alireza Fatemi, Anthony Michael Coppola
  • Patent number: 11575283
    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: Grant
    Filed: October 1, 2019
    Date of Patent: February 7, 2023
    Assignee: GM Global Technology Operations LLC
    Inventors: Alireza Fatemi, Thomas W. Nehl
  • Patent number: 11575299
    Abstract: A method for constructing a rotor assembly for use with a rotary electric machine includes forming annular rotor laminations from metal blanks. Each lamination has a radial axis and an outer diameter surface. Multiple magnet web regions are defined in proximity to the outer diameter surface. Each web regions includes asymmetrical openings defined by a radially-extending strut and arcuate peripheral bridges. The method includes coaxially stacking the laminations into a rotor stack, including positioning every other lamination a predetermined angular distance with to unmask the bridges and/or struts and mask remaining surface area of the laminations. The rotor stack is subjected to a heat-treating process to harden only the unmasked bridges and/or struts. The method includes connecting a rotor shaft to the stack to construct the rotor assembly, with the web regions corresponding to a respective rotor magnetic pole.
    Type: Grant
    Filed: January 7, 2020
    Date of Patent: February 7, 2023
    Assignee: GM Global Technology Operations LLC
    Inventors: Derek F. Lahr, Alireza Fatemi, Anthony M. Coppola, Sean R. Wagner
  • Publication number: 20230018286
    Abstract: A rotor for an electric machine includes a rotor body formed from a plurality of rotor laminations defining a first axial end and a second axial end. Each of the plurality of rotor laminations includes a plurality of openings that are aligned so as to define a plurality of passages through the rotor body. A plurality of reinforcement elements extend through the plurality of laminations. Each of the plurality of reinforcement elements is arranged in a corresponding one of the plurality of passages and includes a first end portion and a second end portion. The first end portion and the second end portion of select ones of the plurality of reinforcement elements extend outwardly of the first axial end and the second axial end. An end ring is positioned at the first axial end. The end ring is integrally formed with the select ones of the plurality of reinforcement elements.
    Type: Application
    Filed: July 15, 2021
    Publication date: January 19, 2023
    Inventors: Alireza Fatemi, Anthony Michael Coppola, Derek Frei Lahr
  • Publication number: 20230018618
    Abstract: An electric machine includes a housing, a rotor rotatably mounted to the housing, and a stator mounted to the housing about the rotor. The stator includes a stator body formed from a plurality of laminations. The plurality of laminations include an outer annular surface defining a radius, an inner annular surface spaced from the rotor, and a plurality of radially inwardly extending stator teeth spaced one from another by plurality of gaps. Each of the plurality of gaps extend along the radius and include an opening exposed at the inner annular surface. The opening has a first side portion and a second side portion each extending at an angle relative to the radius.
    Type: Application
    Filed: July 14, 2021
    Publication date: January 19, 2023
    Inventors: Alireza Fatemi, Mohammad F. Momen, Thomas W. Nehl
  • Publication number: 20230017309
    Abstract: A rotor for an electric machine includes a rotor body formed from a plurality of stacked laminations defining a first axial end and an opposing second axial end. Each of the plurality of stacked laminations includes a plurality of openings that are aligned so as to define a plurality of passages through the rotor body. A plurality of reinforcement elements extend through the plurality of stacked laminations. Each of the plurality of reinforcement elements is arranged in a corresponding one of the plurality of passages and includes a first end portion and a second end portion. The first end portion and the second end portion of select ones of the plurality of reinforcement elements extend outwardly of the first axial end and the second axial end.
    Type: Application
    Filed: July 13, 2021
    Publication date: January 19, 2023
    Inventors: Alireza Fatemi, Anthony Michael Coppola, Derek Frei Lahr, Kestutis A. Sonta
  • Patent number: 11552519
    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: Grant
    Filed: March 24, 2022
    Date of Patent: January 10, 2023
    Assignee: GM Global Technology Operations LLC
    Inventors: Thomas W. Nehl, Alireza Fatemi
  • Patent number: 11545860
    Abstract: A rotor core for an electric motor includes a core stack including a plurality of lamination plates, each lamination plate including a plurality of apertures formed therein, the plurality of apertures of each of the lamination plates axially aligned and defining a plurality of axial magnet slots extending through the core stack and adapted to support a plurality of permanent magnets therein, and at least one insert extending axially through the core stack and adapted to provide radial structural stability to the plurality of lamination plates to prevent portions of the plurality of lamination plates adjacent the plurality of magnet slots from flexing due to radial forces exerted on the plurality of lamination plates during operation of the electric motor.
    Type: Grant
    Filed: February 22, 2021
    Date of Patent: January 3, 2023
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Derek F. Lahr, Alireza Fatemi, Farzad Sarnie, Thomas W. Nehl
  • Publication number: 20220393620
    Abstract: The present disclosure discloses a vehicle propulsion system. The vehicle propulsion system includes a first electric machine including a first set of machine windings that are configured to cause a rotor to rotate about an axis to selectively drive a transmission during a first vehicle operating state and a second electric machine including a second set of machine windings that are configured to cause a rotor to rotate about an axis selectively drive the transmission during at least one of the first vehicle operating state or a second vehicle operating state. The second vehicle operating state different from the first operating state, and a number of series turns per phase for the first set of machine windings is different from a number of series turns per phase for the second set of machine windings.
    Type: Application
    Filed: June 4, 2021
    Publication date: December 8, 2022
    Inventors: Alireza Fatemi, Thomas W. Nehl, Norman K. Bucknor
  • Publication number: 20220355703
    Abstract: An electric propulsion system includes a rotary electric machine having an output member, a rechargeable energy storage system (“RESS”) connected to the electric machine, a user interface device, and a controller. The RESS includes multiple battery modules and a switching circuit, the latter being configured, in response to electronic switching control signals, to connect the battery modules in a parallel-connected (“P-connected”) configuration or a series-connected (“S-connected”) configuration, as a selected battery configuration. The user interface device receives an operator-requested drive mode signal indicative of a desired drive mode of the electric propulsion system.
    Type: Application
    Filed: May 6, 2021
    Publication date: November 10, 2022
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Alireza Fatemi, Thomas W. Nehl, Chandra S. Namuduri, Lei Hao, Norman K. Bucknor, Rashmi Prasad
  • Patent number: 11489472
    Abstract: A motor control system includes: a d-q target module configured to, based on a target torque of an electric motor, determine a first target d-axis current and a first target q-axis current; an offset module configured to, based on a capacitor current through capacitors connected across phases of the electric motor, determine a d-axis current offset and a q-axis current offset; an adder module configured to determine a second target d-axis current based on a sum of the first target d-axis current and the d-axis current offset and to determine a second target q-axis current based on a sum of the first target q-axis current and the q-axis current offset; and a driver module configured to, based on the second target d-axis current and the second target q-axis current, switch switches of a current source inverter (CSI) module configured to apply power to the phases of the electric motor.
    Type: Grant
    Filed: March 3, 2021
    Date of Patent: November 1, 2022
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Suresh Gopalakrishnan, Chandra S. Namuduri, Lei Hao, Muhammad H. Alvi, Alireza Fatemi
  • Patent number: 11476733
    Abstract: A rotary electric machine for use with coolant includes a stator and rotor assembly. The rotor assembly includes a rotor, rotor shaft, and first and second end rings. The rotor has inner and outer diameter surfaces and an embedded set of rotor magnets proximate the outer diameter surface. The shaft is connected to the rotor and defines a main coolant passage along an axis of rotation. Radial shaft coolant passages are in fluid communication with the main coolant passage. The end rings are positioned at opposing distal ends of the rotor. The shaft coolant passages direct the coolant into the rotor and/or the end rings such that the coolant flows axially through rotor cavities of the rotor and cools the rotor magnets via forced convection.
    Type: Grant
    Filed: November 1, 2019
    Date of Patent: October 18, 2022
    Assignee: GM Global Technology Operations LLC
    Inventors: Farzad Samie, Alireza Fatemi, Derek F. Lahr, Erik B. Golm, Xiaofeng Yang
  • Patent number: 11451123
    Abstract: An electric machine includes a stator and a rotor positioned in operational engagement with one another and defining a radial gap extending circumferentially between the stator and the rotor, the rotor including a plurality of rotor segments defining a plurality of segment gaps between adjacent pairs of the plurality of rotor segments, the rotor segments radially moveable relative to the stator, wherein movement of the plurality of rotor segments radially outward increases the radial gap between the stator and the rotor and the segment gaps between adjacent pairs of the plurality of rotor segments.
    Type: Grant
    Filed: October 29, 2020
    Date of Patent: September 20, 2022
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Alireza Fatemi, Thomas W. Nehl, Derek F. Lahr
  • Publication number: 20220294376
    Abstract: An electric machine disposed within a housing includes a stator, a rotor, and one or more point field detectors. The stator receives current from an inverter. The rotor is connected to and rotating a shaft based on a magnetic field generated by the stator. The one or more point field detectors are configured to detect leakage flux within the housing. The stator, the rotor and the one or more point field detectors are disposed within the housing.
    Type: Application
    Filed: March 9, 2021
    Publication date: September 15, 2022
    Inventors: Muhammad H. ALVI, Alireza FATEMI, Suresh GOPALAKRISHNAN, Chandra S. NAMUDURI
  • Publication number: 20220286064
    Abstract: A current source inverter includes a first phase leg including a plurality of switching devices, a second phase leg including a plurality of switching devices, and a third phase leg including a plurality of switching devices. The current source inverter also includes a zero-state phase leg including at least one switching device, wherein the zero-state phase leg is configured to transition from an open state to prevent current flow to a closed state to allow current flow between a positive and negative terminal during a dead-band time.
    Type: Application
    Filed: March 5, 2021
    Publication date: September 8, 2022
    Inventors: Muhammad H. Alvi, Alireza Fatemi, Suresh Gopalakrishnan
  • Publication number: 20220286072
    Abstract: A motor control system includes: a d-q target module configured to, based on a target torque of an electric motor, determine a first target d-axis current and a first target q-axis current; an offset module configured to, based on a capacitor current through capacitors connected across phases of the electric motor, determine a d-axis current offset and a q-axis current offset; an adder module configured to determine a second target d-axis current based on a sum of the first target d-axis current and the d-axis current offset and to determine a second target q-axis current based on a sum of the first target q-axis current and the q-axis current offset; and a driver module configured to, based on the second target d-axis current and the second target q-axis current, switch switches of a current source inverter (CSI) module configured to apply power to the phases of the electric motor.
    Type: Application
    Filed: March 3, 2021
    Publication date: September 8, 2022
    Inventors: Suresh GOPALAKRISHNAN, Chandra S. NAMUDURI, Lei HAO, Muhammad H. ALVI, Alireza FATEMI