Patents by Inventor Sang Gyu Choi

Sang Gyu Choi 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: 20240429807
    Abstract: A balancing circuit according to an embodiment of the present invention comprises: a second resistor connected to the same node as that of a first resistor of a voltage sensing unit connected to a first terminal of an output end of a power conversion device; and a fourth resistor connected to the same node as that of a third resistor of the voltage sensing unit connected to a second terminal of the output end of the power conversion device, wherein the second resistor and the fourth resistor are connected to an upper switch of the power conversion device.
    Type: Application
    Filed: July 4, 2022
    Publication date: December 26, 2024
    Inventors: Dong Keun YOON, Sung Jae KONG, Sang Gyu CHOI
  • Patent number: 11916512
    Abstract: An embodiment provides a DC-DC converter for sensing a grounded state and a method for controlling same in a photovoltaic energy storage system. Specifically, the converter can sense a grounded state on the basis of the magnitude of voltage applied to a resistor and provide a notification.
    Type: Grant
    Filed: August 26, 2019
    Date of Patent: February 27, 2024
    Assignee: LG INNOTEK CO., LTD.
    Inventors: Sang Gyu Choi, Jae Geun Lee, Jeong Heum Lee
  • Patent number: 11418116
    Abstract: According to one embodiment, a DC-DC converter for compensating a ripple in a photovoltaic-linked energy storage system and a control method thereof are disclosed. Particularly, a DC-DC converter for compensating for a ripple generated in a DC link connecting a single-phase inverter to a converter is disclosed. The DC-DC converter can compensate a ripple by using an active power component or the average voltage of a DC link voltage acquired from the DC link.
    Type: Grant
    Filed: December 17, 2018
    Date of Patent: August 16, 2022
    Assignee: LG INNOTEK CO., LTD.
    Inventors: Sang Gyu Choi, Jeong Heum Lee, Ju Young Jang
  • Publication number: 20210328547
    Abstract: An embodiment provides a DC-DC converter for sensing a grounded state and a method for controlling same in a photovoltaic energy storage system. Specifically, the converter can sense a grounded state on the basis of the magnitude of voltage applied to a resistor and provide a notification.
    Type: Application
    Filed: August 26, 2019
    Publication date: October 21, 2021
    Applicant: LG INNOTEK CO., LTD.
    Inventors: Sang Gyu CHOI, Jae Geun LEE, Jeong Heum LEE
  • Publication number: 20210320589
    Abstract: According to one embodiment, a DC-DC converter for compensating a ripple in a photovoltaic-linked energy storage system and a control method thereof are disclosed. Particularly, a DC-DC converter for compensating for a ripple generated in a DC link connecting a single-phase inverter to a converter is disclosed. The DC-DC converter can compensate a ripple by using an active power component or the average voltage of a DC link voltage acquired from the DC link.
    Type: Application
    Filed: December 17, 2018
    Publication date: October 14, 2021
    Applicant: LG INNOTEK CO., LTD.
    Inventors: Sang Gyu CHOI, Jeong Heum LEE, Ju Young JANG
  • Patent number: 8678299
    Abstract: A hollow actuator-driven droplet dispensing apparatus may include an elastic tube having an elastic body, defining a storage space therein, and extending a predetermined length, and a hollow actuator fitted around the elastic tube so as to generate a force and a displacement in the longitudinal direction when an electric field is applied. The hollow actuator is expanded or contracted in the longitudinal direction of the elastic tube when the external voltage is applied, thereby reducing or enlarging the volume of an inner space of the elastic tube. The droplet dispensing apparatus can press the elastic tube to expand or contract the volume of the inner space of the tube using the hollow actuator capable of quickly generating a displacement in response to an application voltage so that a fixed amount of content can be discharged out and taken into the tube.
    Type: Grant
    Filed: October 27, 2009
    Date of Patent: March 25, 2014
    Assignee: Korea Institute of Machinery & Materials
    Inventors: Young Bog Ham, Jung Ho Park, So Nam Yun, Sang Gyu Choi
  • Publication number: 20100102093
    Abstract: A hollow actuator-driven droplet dispensing apparatus may include an elastic tube having an elastic body, defining a storage space therein, and extending a predetermined length, and a hollow actuator fitted around the elastic tube so as to generate a force and a displacement in the longitudinal direction when an electric field is applied. The hollow actuator is expanded or contracted in the longitudinal direction of the elastic tube when the external voltage is applied, thereby reducing or enlarging the volume of an inner space of the elastic tube. The droplet dispensing apparatus can press the elastic tube to expand or contract the volume of the inner space of the tube using the hollow actuator capable of quickly generating a displacement in response to an application voltage so that a fixed amount of content can be discharged out and taken into the tube.
    Type: Application
    Filed: October 27, 2009
    Publication date: April 29, 2010
    Applicant: KOREA INSTITUTE OF MACHINERY & MATERIALS
    Inventors: Young Bog Ham, Jung Ho Park, So Nam Yun, Sang Gyu Choi