Patents by Inventor Cheewoo Lee

Cheewoo Lee 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: 9413213
    Abstract: A stator of a switched reluctance motor includes a stator core part, stator coiling parts, stator salient parts, and pairs of permanent magnets. The stator coiling parts protrude inwardly from the stator core part and have coils wound on an external side thereof. The stator salient parts protrude inwardly from the stator core part and are disposed between the stator coiling parts. Each pair of the permanent magnets is inserted into each of the stator coiling parts and magnetized in the same direction as a direction of a magnetic field generated by the excitation of the coils. This stator has an electromagnetic structure designed to prevent the reversal of a magnetic field generated by the excited coils. The output of the motor is enhanced by inserting the permanent magnets so as to be magnetized in the same direction as a direction of a magnetic field generated by the excited coils.
    Type: Grant
    Filed: September 23, 2013
    Date of Patent: August 9, 2016
    Assignees: KOREA ELECTRONICS TECHNOLOGY INSTITUTE, UNIVERSITY OF ULSAN FOUNDATION FOR INDUSTRY COOPERATION
    Inventors: Cheewoo Lee, Jin Hur, Jeongjong Lee, Sehyun Rhyu, Jungmoo Seo, Youngkyoun Kim, Insoung Jung
  • Publication number: 20150035389
    Abstract: A stator of a switched reluctance motor includes a stator core part, stator coiling parts, stator salient parts, and pairs of permanent magnets. The stator coiling parts protrude inwardly from the stator core part and have coils wound on an external side thereof. The stator salient parts protrude inwardly from the stator core part and are disposed between the stator coiling parts. Each pair of the permanent magnets is inserted into each of the stator coiling parts and magnetized in the same direction as a direction of a magnetic field generated by the excitation of the coils. This stator has an electromagnetic structure designed to prevent the reversal of a magnetic field generated by the excited coils. The output of the motor is enhanced by inserting the permanent magnets so as to be magnetized in the same direction as a direction of a magnetic field generated by the excited coils.
    Type: Application
    Filed: September 23, 2013
    Publication date: February 5, 2015
    Applicant: University of Ulsan Foundation For Industry Cooperation
    Inventors: Cheewoo LEE, Jin HUR, Jeongjong LEE, Sehyun RHYU, Jungmoo SEO, Youngkyoun KIM, Insoung JUNG
  • Patent number: 8901798
    Abstract: A two-phase switched reluctance machine is provided using discontinuous core structures as the stator for low-cost, high-performance drives. This discontinuous stator core structure contains short flux paths and maximum overlap between the rotor poles and stator poles in the stator discontinuous core structures, regardless of the rotor position. Example configurations of such core structure include E-core, L-core and I-core configurations. Using less steel and magnet wire than in conventional SRM designs results in cost savings of stator material and winding material. Efficiency of this novel SRM is improved because of shorter flux paths resulting in reduction of core losses and decreased phase resistance resulting in reduction of copper losses. Two-phase simultaneous excitation of the novel SRM can reduce torque ripple during commutation as compared with existing two-phase SRMs.
    Type: Grant
    Filed: May 30, 2008
    Date of Patent: December 2, 2014
    Assignee: Regal Beloit America, Inc.
    Inventors: Krishnan Ramu, Nimai Lobo, Cheewoo Lee
  • Publication number: 20100141061
    Abstract: A two-phase switched reluctance machine is provided using discontinuous core structures as the stator for low-cost, high-performance drives. This discontinuous stator core structure contains short flux paths and maximum overlap between the rotor poles and stator poles in the stator discontinuous core structures, regardless of the rotor position. Example configurations of such core structure include E-core, L-core and I-core configurations. Using less steel and magnet wire than in conventional SRM designs results in cost savings of stator material and winding material. Efficiency of this novel SRM is improved because of shorter flux paths resulting in reduction of core losses and decreased phase resistance resulting in reduction of copper losses. Two-phase simultaneous excitation of the novel SRM can reduce torque ripple during commutation as compared with existing two-phase SRMs.
    Type: Application
    Filed: May 30, 2008
    Publication date: June 10, 2010
    Inventors: Krishnan Ramu, Nimai Lobo, Cheewoo Lee