Patents by Inventor Ick Choy

Ick Choy 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: 7141943
    Abstract: A brushless DC (BLDC) motor system and a method of controlling the same are provided. The BLDC motor system comprises a BLDC motor including a rotator and a stator, a plurality of switches, a DC current sensor, a position detector and a controller. The stator has a plurality of coils to which currents having different phase are applied. The switches are driven with switching pulses for switching the currents applied to the coils. The position detector detects a position change of the rotator to thereby generate a counter-electromotive force and the DC current sensor senses currents when the currents are applied from the switches to the coils. Based on a magnitude of the counter electromotive force, the controller generates a compensation voltage in order to control the switches during the commutation interval. Further, a duty ratio of the switching pulse is controlled based on the differences between the currents applied to the coils and a reference current.
    Type: Grant
    Filed: December 30, 2004
    Date of Patent: November 28, 2006
    Assignee: Korean Institute of Science and Technology
    Inventors: Joong-Ho Song, Ick Choy
  • Publication number: 20060145639
    Abstract: A brushless DC (BLDC) motor system and a method of controlling the same are provided. The BLDC motor system comprises a BLDC motor including a rotator and a stator, a plurality of switches, a DC current sensor, a position detector and a controller. The stator has a plurality of coils to which currents having different phase are applied. The switches are driven with switching pulses for switching the currents applied to the coils. The position detector detects a position change of the rotator to thereby generate a counter-electromotive force and the DC current sensor senses currents when the currents are applied from the switches to the coils. Based on a magnitude of the counter electromotive force, the controller generates a compensation voltage in order to control the switches during the commutation interval. Further, a duty ratio of the switching pulse is controlled based on the differences between the currents applied to the coils and a reference current.
    Type: Application
    Filed: December 30, 2004
    Publication date: July 6, 2006
    Inventors: Joong-Ho Song, Ick Choy