Patents by Inventor Ryousuke Nakagawa

Ryousuke Nakagawa 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).

  • Three-level power converting apparatus
    Patent number: 7978488
    Abstract: Each phase of a three-level power converting apparatus is configured by a single unit, and four switching devices (1u-4u) and two diodes (9u, 10u) provided in each unit are arranged along a flow direction of cooling air on a heat sink (15) of a cooling device with long sides of the switching devices (1u-4u) and the diodes (9u, 10u) oriented perpendicular to the flow direction of the cooling air. The first and second diodes (9u, 10u) are arranged in a central area of the heat sink (15), whereas the second switching device (2u) and the third switching device (3u) with high heat generation loss are arranged in a distributed fashion to sandwich a group of diodes in the central area in between.
    Type: Grant
    Filed: April 7, 2006
    Date of Patent: July 12, 2011
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takeshi Tanaka, Ryousuke Nakagawa
  • Three-level power converting apparatus
    Publication number: 20090207639
    Abstract: Each phase of a three-level power converting apparatus is configured by a single unit, and four switching devices (1u-4u) and two diodes (9u, 10u) provided in each unit are arranged along a flow direction of cooling air on a heat sink (15) of a cooling device with long sides of the switching devices (1u-4u) and the diodes (9u, 10u) oriented perpendicular to the flow direction of the cooling air. The first and second diodes (9u, 10u) are arranged in a central area of the heat sink (15), whereas the second switching device (2u) and the third switching device (3u) with high heat generation loss are arranged in a distributed fashion to sandwich a group of diodes in the central area in between.
    Type: Application
    Filed: April 7, 2006
    Publication date: August 20, 2009
    Applicant: Mitsubishi Electric Corporation
    Inventors: Takeshi Tanaka, Ryousuke Nakagawa