Patents by Inventor Ahn Byong-Ho

Ahn Byong-Ho 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: 4868479
    Abstract: A back EMF controlled, synchronous, permanent magnet motor capable of extremely high rotation speeds at high efficiency. The motor includes a permanent magnet flux source and excitation coils for producing a rotating magnetic field mounted on an iron free form to substantially eliminate core loss and resulting rotor drag. Back EMF is determined directly from the excitation and controls the excitation to produce a torque angle of substantially between the magnet and coil fluxes. Coil excitation is used at maximum efficiency and hunting is avoided. The permanent magnet provides a high flux density that also allows a low current in the motor coils and thus reduces coil copper losses to further improve efficiency.
    Type: Grant
    Filed: August 4, 1987
    Date of Patent: September 19, 1989
    Assignee: The Charles Stark Draper Laboratory, Inc.
    Inventors: Ahn Byong-Ho, Donald E. Fulton, Philip J. Gilinson, Jr., David C. Whipple, William P. Curtiss