Patents by Inventor Shuji Katoh

Shuji Katoh 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: 11444552
    Abstract: The present invention provides an electric power conversion device and an electric power generation system which are capable of suppressing ripples in a detected voltage and detection delay.
    Type: Grant
    Filed: March 30, 2020
    Date of Patent: September 13, 2022
    Assignee: TOHOKU UNIVERSITY
    Inventors: Shuji Katoh, Yoshikazu Takahashi, Tetsuo Endoh
  • Publication number: 20220190741
    Abstract: The present invention provides an electric power conversion device and an electric power generation system which are capable of suppressing ripples in a detected voltage and detection delay.
    Type: Application
    Filed: March 30, 2020
    Publication date: June 16, 2022
    Inventors: Shuji Katoh, Yoshikazu Takahashi, Tetsuo Endoh
  • Patent number: 10243365
    Abstract: Conventionally, optimum introduction assistance for devices including a FACTS device and a storage adapted to changes in impedance and a transmission capacity involved in an increase of renewable energy power supplies has not been achieved. Therefore, in order to solve the problem, the present invention provides a power system equipment introduction assistance device that calculates an introduction point of power system equipment coupled to a power system, the introduction assistance device including a calculating unit configured to calculate, on the basis of predetermined system information and information concerning the power system equipment scheduled to be introduced, a characteristic of the power system affecting the power system during the introduction of the power system equipment and calculate the introduction point of the power system equipment from a predetermined evaluation index related to the characteristic of the power system.
    Type: Grant
    Filed: May 27, 2015
    Date of Patent: March 26, 2019
    Assignee: Hitachi, Ltd.
    Inventors: Efrain Eduardo Tamayo Ruiz, Shuji Katoh, Shinya Oohara, Shigenori Inoue, Tohru Yoshihara
  • Publication number: 20180159329
    Abstract: Conventionally, optimum introduction assistance for devices including a FACTS device and a storage adapted to changes in impedance and a transmission capacity involved in an increase of renewable energy power supplies has not been achieved. Therefore, in order to solve the problem, the present invention provides a power system equipment introduction assistance device that calculates an introduction point of power system equipment coupled to a power system, the introduction assistance device including a calculating unit configured to calculate, on the basis of predetermined system information and information concerning the power system equipment scheduled to be introduced, a characteristic of the power system affecting the power system during the introduction of the power system equipment and calculate the introduction point of the power system equipment from a predetermined evaluation index related to the characteristic of the power system.
    Type: Application
    Filed: May 27, 2015
    Publication date: June 7, 2018
    Inventors: Efrain Eduardo TAMAYO RUIZ, Shuji KATOH, Shinya OOHARA, Shigenori INOUE, Tohru YOSHIHARA
  • Patent number: 9917534
    Abstract: A power conversion device is provided which includes a plurality of series circuits each formed of a voltage source and a controlled current source. At least two of said series circuits formed of the voltage source and the controlled current source are connected in parallel. Further, parallel connection points of the series circuits connected in parallel form output terminals.
    Type: Grant
    Filed: August 26, 2016
    Date of Patent: March 13, 2018
    Assignee: HITACHI, LTD.
    Inventors: Shigenori Inoue, Shuji Katoh, Jun Narushima, Tetsuya Kato
  • Publication number: 20160365807
    Abstract: A power conversion device is provided which includes a plurality of series circuits each formed of a voltage source and a controlled current source. At least two of said series circuits formed of the voltage source and the controlled current source are connected in parallel. Further, parallel connection points of the series circuits connected in parallel form output terminals.
    Type: Application
    Filed: August 26, 2016
    Publication date: December 15, 2016
    Applicant: HITACHI, LTD.
    Inventors: Shigenori Inoue, Shuji Katoh, Jun Narushima, Tetsuya Kato
  • Patent number: 9461560
    Abstract: A power conversion device is provided which includes a plurality of series circuits each formed of a voltage source and a controlled current source. At least two of said series circuits formed of the voltage source and the controlled current source are connected in parallel. Further, parallel connection points of the series circuits connected in parallel form output terminals.
    Type: Grant
    Filed: February 21, 2014
    Date of Patent: October 4, 2016
    Assignee: HITACHI, LTD.
    Inventors: Shigenori Inoue, Shuji Katoh, Jun Narushima, Tetsuya Kato
  • Patent number: 9344020
    Abstract: A power conversion apparatus includes arms in each of which one or more unit converters each including a capacitor and capable of outputting an arbitrary voltage are connected in series, and a point P as a first node to which one end of the respective arms are Y-connected, and a point N as a second node to which a neutral terminal of the rotary electric machine is connected. The other end of the respective arms are connected to one ends of respective phase windings of a rotary electric machine.
    Type: Grant
    Filed: July 1, 2014
    Date of Patent: May 17, 2016
    Assignee: Hitachi, Ltd.
    Inventors: Shigenori Inoue, Shuji Katoh, Hironari Kawazoe, Osamu Tomobe, Toru Yoshihara, Kenta Watanabe
  • Patent number: 9252684
    Abstract: A power conversion apparatus including a three-phase transformer having at least four three-phase windings, and three converter arms each configured by connecting one or plural unit converters each including a switching device and an energy storage element in series. A power source or a load is connected to a first three-phase winding of the transformer, three series circuits which connects second and third three-phase windings of the transformer, and the converter arms in series with each other are connected in parallel, the parallel connection point is a DC terminal, and a magnitude relationship between a coupling coefficient of the first and second three-phase windings, and a coupling coefficient of the first three- and third three-phase windings is equal to a magnitude relationship between a coupling coefficient of the fourth and second three-phase windings, and a coupling coefficient of the fourth and the third three-phase windings.
    Type: Grant
    Filed: January 21, 2014
    Date of Patent: February 2, 2016
    Assignee: HITACHI, LTD.
    Inventors: Shigenori Inoue, Shuji Katoh, Yasuhiro Kiyofuji, Makoto Kadowaki, Hiroyuki Fujita, Hideki Ogata
  • Patent number: 9219426
    Abstract: A switching element of a power converter generates a low voltage, using a current flowing in the power converter, and supplies a power to drive itself. A switching element of a power converter for conversion from direct current into alternate current or from alternate current into direct current includes: a terminal and a terminal which are used in building the switching element itself in the power converter; a capacitor, a high-side controllable switch and a low-side controllable switch enabling outputting the voltage of the capacitor, the voltage being output between the terminal and the terminal, and a self-supply power source for supplying a power to drive the bi-directional chopper switching element itself, using a current flowing in the capacitor.
    Type: Grant
    Filed: February 8, 2013
    Date of Patent: December 22, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Takayoshi Yamamoto, Masaya Ichinose, Akira Bando, Keiichi Yamashita, Shigenori Inoue, Toru Yoshihara, Yoshio Eguchi, Osamu Sakuchi, Shuji Katoh, Tomomichi Ito
  • Patent number: 9190930
    Abstract: A power conversion device includes at least two legs connected in parallel each of which includes at least two unit converters connected in series, wherein at least one of the legs is formed using at least two kinds of unit converters including a first type unit converter capable of outputting a unipolar voltage and a second type unit converter capable of outputting a bipolar voltage.
    Type: Grant
    Filed: December 6, 2012
    Date of Patent: November 17, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Shigenori Inoue, Shuji Katoh
  • Patent number: 9105397
    Abstract: The present invention provides an inter-bus-bar built-in capacitor capable of reducing the size of a capacitor used in an inverter or the like or downsizing the capacitor, and provides power equipment as well as a power converting apparatus. The inter-bus-bar built-in capacitor is provided between a pair of opposing bus bars and includes a high-dielectric-constant material which has a relative dielectric constant of at least 50 when a voltage of 1,000 V is applied at a temperature of 25° C. Thus, it is possible to provide the inter-bus-bar built-in capacitor capable of reducing the size of a capacitor used in an inverter or the like or downsizing the capacitor and provide the power equipment as well as the power converting apparatus.
    Type: Grant
    Filed: October 11, 2011
    Date of Patent: August 11, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Yuichiro Yoshitake, Shuji Katoh, Hiroshi Morita, Atsushi Ootake
  • Publication number: 20150008859
    Abstract: A power conversion apparatus includes arms in each of which one or more unit converters each including a capacitor and capable of outputting an arbitrary voltage are connected in series, and a point P as a first node to which one end of the respective arms are Y-connected, and a point N as a second node to which a neutral terminal of the rotary electric machine is connected. The other end of the respective arms are connected to one ends of respective phase windings of a rotary electric machine.
    Type: Application
    Filed: July 1, 2014
    Publication date: January 8, 2015
    Applicant: HITACHI, LTD.
    Inventors: Shigenori INOUE, I, Shuji KATOH, Hironari KAWAZOE, Osamu TOMOBE, Toru YOSHIHARA, Kenta WATANABE
  • Publication number: 20140268896
    Abstract: A reactor apparatus 10 includes two yoke iron cores 11a, 11b disposed opposite each other, a plurality of magnetic leg iron cores 31 each of which has a coil 21 wound therearound and provided with a gap adjusting means 5a, 5b, and one or more zero-phase magnetic leg iron cores 41 around which a coil is not wound, wherein the two yoke iron cores 11a, 11b disposed opposite each other are connected to each other with the plurality of magnetic leg iron cores 31 and the one or more zero-phase magnetic leg iron cores 41. In addition, the reactor apparatus is used for a power converter.
    Type: Application
    Filed: May 16, 2011
    Publication date: September 18, 2014
    Applicant: Hitachi Ltd.
    Inventors: Naoyuki Kurita, Kazumasa Ide, Shuji Katoh
  • Patent number: 8817503
    Abstract: Disclosed is a power conversion device, wherein among the optical fiber cables used in control/communication, at least the majority of high-voltage optical fiber cables with a dielectric strength against the output voltages of a plurality of cells can be eliminated and thus a low-voltage optical fiber cable with a dielectric strength against the output voltage of one cell can be used. Furthermore, here, the length required for the optical fiber cable can be reduced. A controller of the power conversion device comprising a plurality of cascade-connected cells comprises a central controller, and a cell controller with the same potential as each cell, the cell controller being installed in the vicinity of each cell, wherein the central controller and each cell controller are daisy-chained using an optical fiber cable.
    Type: Grant
    Filed: July 13, 2010
    Date of Patent: August 26, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Shigenori Inoue, Shuji Katoh, Tetsuya Kato
  • Publication number: 20140211528
    Abstract: A power conversion apparatus including a three-phase transformer having at least four three-phase windings, and three converter arms each configured by connecting one or plural unit converters each including a switching device and an energy storage element in series. A power source or a load is connected to a first three-phase winding of the transformer, three series circuits which connects second and third three-phase windings of the transformer, and the converter arms in series with each other are connected in parallel, the parallel connection point is a DC terminal, and a magnitude relationship between a coupling coefficient of the first and second three-phase windings, and a coupling coefficient of the first three- and third three-phase windings is equal to a magnitude relationship between a coupling coefficient of the fourth and second three-phase windings, and a coupling coefficient of the fourth and the third three-phase windings.
    Type: Application
    Filed: January 21, 2014
    Publication date: July 31, 2014
    Applicant: HITACHI, LTD.
    Inventors: Shigenori INOUE, Shuji KATOH, Yasuhiro KIYOFUJI, Makoto KADOWAKI, Hiroyuki FUJITA, Hideki OGATA
  • Patent number: 8792261
    Abstract: A power conversion device connected with a three-phase power system through a transformer, including unit converters cascade-connected so that reactors are unnecessary, and volume and weight are reduced. The secondary winding of the transformer is an open winding having six terminals. A first converter group, includes a circuit which has three converter arms, which are star-connected, connected to three of the terminals of the secondary winding. A second converter group, having three different converter arms which are star-connected, is connected to three other terminals of the secondary winding. A neutral point (the point where the star connection is made) of the first converter group, and a neutral point of the second converter group are made to be the output terminals of the power conversion device.
    Type: Grant
    Filed: February 24, 2010
    Date of Patent: July 29, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Shigenori Inoue, Shuji Katoh, Jun Narushima, Tetsuya Kato
  • Publication number: 20140169048
    Abstract: A power conversion device is provided which includes a plurality of series circuits each formed of a voltage source and a controlled current source. At least two of said series circuits formed of the voltage source and the controlled current source are connected in parallel. Further, parallel connection points of the series circuits connected in parallel form output terminals.
    Type: Application
    Filed: February 21, 2014
    Publication date: June 19, 2014
    Applicant: Hitachi, Ltd.
    Inventors: Shigenori INOUE, Shuji KATOH, Jun NARUSHIMA, Tetsuya KATO
  • Patent number: 8711586
    Abstract: The noise generated from a power converter is suppressed by increasing the noise frequency to a level not lower than the maximum frequency of the human audible range. To obtain the frequency of an output current harmonic component as a noise source which has exceeded the maximum frequency of the human audible range, it is adequate to determine that the frequency of a driving carrier wave for the individual converter cells in the power converter, in which the phases of the carrier wave for the converter cells are mutually shifted by a given value between the converter cells, meets the following equation.
    Type: Grant
    Filed: July 20, 2010
    Date of Patent: April 29, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Yoichiro Yamada, Shuji Katoh, Shigenori Inoue
  • Publication number: 20140078796
    Abstract: In the present invention, provided is a power conversion apparatus in which at least one energy storage element and at least one switching element are included, a plurality of series circuits of a transformer winding and an arm in which one or a plurality of at least two-terminal unit converters which depend on ON/OFF of the switching element and supply a zero voltage or a voltage depending on a voltage of the energy storage element are connected in series are connected in parallel, and a multi-phase power source or a multi-phase load is connected to another winding of the transformer, and the parallel-connection point is set as a DC terminal, and which includes means for controlling a current flowing through each of the arms to have a phase and amplitude different from each other.
    Type: Application
    Filed: August 28, 2013
    Publication date: March 20, 2014
    Applicant: Hitachi, Ltd.
    Inventors: Shigenori INOUE, Shuji KATOH, Akira BANDO, Yasuhiro KIYOFUJI, Yoshio EGUCHI, Masaya ICHINOSE, Takayoshi YAMAMOTO