Patents by Inventor Shoya AKAZAWA

Shoya AKAZAWA 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).

  • Power conversion device
    Patent number: 11456678
    Abstract: In order to reduce noise current leaking out from a frame to which semiconductor devices constituting a three-level power conversion circuit are attached to the outside of a power conversion device, the frame to which the semiconductor devices constituting the three-level power conversion circuit with which the power conversion device is equipped are attached is configured to be electrically connected to a neutral point of the three-level power conversion circuit. The noise current leaking out from the frame is thereby drawn back to the neutral point of the three-level power conversion circuit to suppress the flowing out of the noise current to the outside of the power conversion device and reduce the noise current.
    Type: Grant
    Filed: October 1, 2019
    Date of Patent: September 27, 2022
    Assignee: Hitachi, Ltd.
    Inventors: Shoya Akazawa, Hiroyuki Ozawa
  • Power Conversion Device
    Publication number: 20210336556
    Abstract: In order to reduce noise current leaking out from a frame to which semiconductor devices constituting a three-level power conversion circuit are attached to the outside of a power conversion device, the frame to which the semiconductor devices constituting the three-level power conversion circuit with which the power conversion device is equipped are attached is configured to be electrically connected to a neutral point of the three-level power conversion circuit. The noise current leaking out from the frame is thereby drawn back to the neutral point of the three-level power conversion circuit to suppress the flowing out of the noise current to the outside of the power conversion device and reduce the noise current.
    Type: Application
    Filed: October 1, 2019
    Publication date: October 28, 2021
    Inventors: Shoya AKAZAWA, Hiroyuki OZAWA