Patents by Inventor Mitsuhiro KADOTA

Mitsuhiro KADOTA 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: 11834033
    Abstract: A power regeneration device 21 that converts the power of a main engine DC line 16 connected to a main engine power generator 12 through a rectification circuit 14 to supply the converted power to an accessory DC line 34 connected to an accessory power generator 31 through a rectification circuit 32 includes a plurality of power conversion modules 221 to 22N configured such that input sections 221a to 22Na are connected in series. The main engine power generator 12 and a power consumption device 15 are controlled such that a voltage input to the power regeneration device 21 does not exceed a voltage upper limit value Vm and a portion between a positive electrode terminal (+) and a negative electrode terminal (?) of each of the input sections of the power conversion modules to be stopped is short-circuited by a bypass device and the voltage upper limit value Vm is decreased when some of the plurality of power conversion modules 221 to 22N are stopped.
    Type: Grant
    Filed: November 27, 2019
    Date of Patent: December 5, 2023
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Mitsuhiro Kadota, Masatsugu Arai, Takayuki Satou, Naoki Fukuda
  • Publication number: 20230261591
    Abstract: When regeneration operation is being performed, electric power on a main-machine side is supplied to an auxiliary-machine side, a voltage on the auxiliary-machine side is controlled to become a first voltage value predetermined on the basis of operating voltage specifications of an auxiliary apparatus, a generator on the auxiliary-machine side is deactivated to stop supply of electric power to the auxiliary-machine side, and electric power on the auxiliary-machine side is supplied to a power storage apparatus.
    Type: Application
    Filed: May 28, 2021
    Publication date: August 17, 2023
    Inventors: Mitsuhiro KADOTA, Yuuichi KUNITOMO, Atsushi KITAGUCHI, Takaaki TANAKA, Naoki FUKUDA
  • Publication number: 20220258593
    Abstract: To provide an electric vehicle capable of reducing heat generation of the switching elements while achieving energy saving, the electric vehicle includes: an engine 11; a first generator 12 driven by the engine; a first rectifier circuit 14 connected to the output of the first generator; a first DC line 16 to receive the DC output of the first rectifier circuit; a driving motor 10 connected to the first DC line; a power converter 20 configured to convert voltage of the first DC line; a second DC line 34 to receive the DC output subjected to voltage conversion by the power converter; an auxiliary device 33 connected to the second DC line; and a controller 40 configured to control the power converter.
    Type: Application
    Filed: July 7, 2020
    Publication date: August 18, 2022
    Inventors: Mitsuhiro KADOTA, Masatsugu ARAI, Atsushi KITAGUCHI, Naoki FUKUDA
  • Publication number: 20220001854
    Abstract: A power regeneration device 21 that converts the power of a main engine DC line 16 connected to a main engine power generator 12 through a rectification circuit 14 to supply the converted power to an accessory DC line 34 connected to an accessory power generator 31 through a rectification circuit 32 includes a plurality of power conversion modules 221 to 22N configured such that input sections 221a to 22Na are connected in series. The main engine power generator 12 and a power consumption device 15 are controlled such that a voltage input to the power regeneration device 21 does not exceed a voltage upper limit value Vm and a portion between a positive electrode terminal (+) and a negative electrode terminal (?) of each of the input sections of the power conversion modules to be stopped is short-circuited by a bypass device and the voltage upper limit value Vm is decreased when some of the plurality of power conversion modules 221 to 22N are stopped.
    Type: Application
    Filed: November 27, 2019
    Publication date: January 6, 2022
    Inventors: Mitsuhiro KADOTA, Masatsugu ARAI, Takayuki SATOU, Naoki FUKUDA
  • Patent number: 11152870
    Abstract: A power conversion device that suppresses voltage pulsation of a capacitor of a power converter with respect to a control target whose effective power is to be controlled is provided. The power conversion device includes a plurality of power conversion cells that are connected to each other, and convert a primary-side system voltage into a secondary-side system voltage, a capacitor that is connected to each of the plurality of power conversion cells, and a power conversion cell driver that drives the power conversion cells to add a 3N order higher-harmonic-wave voltage of each of alternating voltages of the plurality of power conversion cells to the each of alternating voltages, and output a voltage made by adding the each of alternating voltages and the 3N order higher-harmonic-wave voltage, when N is a natural number.
    Type: Grant
    Filed: October 4, 2018
    Date of Patent: October 19, 2021
    Assignee: Hitachi Industrial Products, Ltd.
    Inventors: Kimihisa Furukawa, Akihiko Kanouda, Yuuichi Mabuchi, Hiroyuki Shoji, Takae Shimada, Mitsuhiro Kadota, Mizuki Nakahara
  • Patent number: 11108334
    Abstract: Provided is a power conversion device which can be configured inexpensively and in which initial charging can be performed quickly. Accordingly, the power conversion device is provided with: a power conversion device cell having a first converter for converting a first AC voltage to a first DC voltage, a second converter for converting the first DC voltage to another voltage, and a first capacitor charged by the first DC voltage; and a control circuit for allowing charging of the first capacitor while changing the operational state of the first converter in accordance with the first DC voltage.
    Type: Grant
    Filed: October 18, 2018
    Date of Patent: August 31, 2021
    Assignee: Hitachi Industrial Products, Ltd.
    Inventors: Mizuki Nakahara, Takae Shimada, Kimihisa Furukawa, Mitsuhiro Kadota
  • Publication number: 20210167690
    Abstract: Provided is a power conversion device which can be configured inexpensively and in which initial charging can be performed quickly. Accordingly, the power conversion device is provided with: a power conversion device cell having a first converter for converting a first AC voltage to a first DC voltage, a second converter for converting the first DC voltage to another voltage, and a first capacitor charged by the first DC voltage; and a control circuit for allowing charging of the first capacitor while changing the operational state of the first converter in accordance with the first DC voltage.
    Type: Application
    Filed: October 18, 2018
    Publication date: June 3, 2021
    Inventors: Mizuki NAKAHARA, Takae SHIMADA, Kimihisa FURUKAWA, Mitsuhiro KADOTA
  • Patent number: 10998830
    Abstract: A power conversion device includes: power conversion cells; and a controller to control the cells. Each cell includes: a transformer; a primary conversion unit on a primary side of the transformer; a secondary conversion unit on a secondary side; a primary bypass device for short-circuiting between input terminals of the cell; and a secondary bypass device for short-circuiting between output terminals of the cell. The input terminals and/or the output terminals of the cells are connected in series. When the primary conversion unit(s) of a part of the cells is stopped, the controller turns on the primary bypass device and sets secondary DC link voltages to prescribed values; and when the secondary conversion unit(s) of a part of the cells is stopped, the controller turns on the secondary bypass device and controls the primary conversions units to set primary DC link voltages to prescribed values.
    Type: Grant
    Filed: April 24, 2018
    Date of Patent: May 4, 2021
    Assignee: Hitachi, Ltd.
    Inventors: Mitsuhiro Kadota, Takae Shimada
  • Publication number: 20210044212
    Abstract: A power conversion device that suppresses voltage pulsation of a capacitor of a power converter with respect to a control target whose effective power is to be controlled is provided. The power conversion device includes a plurality of power conversion cells that are connected to each other, and convert a primary-side system voltage into a secondary-side system voltage, a capacitor that is connected to each of the plurality of power conversion cells, and a power conversion cell driver that drives the power conversion cells to add a 3N order higher-harmonic-wave voltage of each of alternating voltages of the plurality of power conversion cells to the each of alternating voltages, and output a voltage made by adding the each of alternating voltages and the 3N order higher-harmonic-wave voltage, when N is a natural number.
    Type: Application
    Filed: October 4, 2018
    Publication date: February 11, 2021
    Inventors: Kimihisa FURUKAWA, Akihiko KANOUDA, Yuuichi MABUCHI, Hiroyuki SHOJI, Takae SHIMADA, Mitsuhiro KADOTA, Mizuki NAKAHARA
  • Patent number: 10862311
    Abstract: A power conversion device includes three first power conversion cells each converting input power and outputting the converted power and having input terminals connected in parallel regarding a first power supply and three second power conversion cells each converting input power and outputting the converted power and having input terminals connected in parallel regarding a second power supply, wherein: the power output from the cell and the power output from the cell are combined to output a first phase power; the power output from the cell and the power output from the cell are combined to output a second phase power; and the power output from the cell and the power output from the cell are combined to output a third phase power. The first phase, second phase, and third phase powers are output as the phase powers or inter-line powers of a three-phase system.
    Type: Grant
    Filed: October 5, 2016
    Date of Patent: December 8, 2020
    Assignee: Hitachi, Ltd.
    Inventors: Mitsuhiro Kadota, Akihiko Kanouda, Yasuaki Norimatsu, Takae Shimada
  • Patent number: 10615715
    Abstract: In a power conversion device, a power conversion unit includes a single-phase inverter on a secondary side of a resonant type converter that has an input of a direct current. A power conversion unit group is configured by connecting outputs of the single-phase inverters of a plurality of power conversion units in series. Respective phases of three phase alternate current are formed with the three power conversion unit groups housed in a power conversion device housing. The plurality of power conversion units constituting the power conversion unit group are disposed along a longitudinal direction of the power conversion device housing. The respective three power conversion unit groups are disposed at an upper stage, a middle stage, and a lower stage in a height direction of the power conversion device housing. The power conversion device housing has one end side in the longitudinal direction as output terminals of the three power conversion unit groups.
    Type: Grant
    Filed: September 6, 2016
    Date of Patent: April 7, 2020
    Assignee: Hitachi, Ltd.
    Inventors: Yasuaki Norimatsu, Akihiko Kanouda, Yuuichi Mabuchi, Takae Shimada, Mitsuhiro Kadota, Yuki Kawaguchi, Mizuki Nakahara, Akira Yonekawa
  • Publication number: 20200091831
    Abstract: A power conversion device includes: power conversion cells; and a controller to control the cells. Each cell includes: a transformer; a primary conversion unit on a primary side of the transformer; a secondary conversion unit on a secondary side; a primary bypass device for short-circuiting between input terminals of the cell; and a secondary bypass device for short-circuiting between output terminals of the cell. The input terminals and/or the output terminals of the cells are connected in series. When the primary conversion unit(s) of a part of the cells is stopped, the controller turns on the primary bypass device and sets secondary DC link voltages to prescribed values; and when the secondary conversion unit(s) of a part of the cells is stopped, the controller turns on the secondary bypass device and controls the primary conversions units to set primary DC link voltages to prescribed values.
    Type: Application
    Filed: April 24, 2018
    Publication date: March 19, 2020
    Inventors: Mitsuhiro KADOTA, Takae SHIMADA
  • Patent number: 10530271
    Abstract: In a power conversion device in a configuration in which a plurality of power converter cells has serially connected outputs and includes a converter and an inverter as components, when a load is light, the cells also operate with a light load, and efficiency is reduced. A power conversion device has a plurality of power converter cells. The outputs of the cells are connected in series. The device has a controller that controls the cells. The cells each have a converter that converts an externally inputted power supply voltage and generates a DC link voltage and an inverter that converts the DC link voltage into an alternating current voltage and outputs the current. The controller stops a converter in some of the cells depending on power supply electric power or load electric power. The inverter continues to operate using a link capacitor as a power supply.
    Type: Grant
    Filed: April 10, 2017
    Date of Patent: January 7, 2020
    Assignee: Hitachi, Ltd.
    Inventors: Mizuki Nakahara, Yasuaki Norimatsu, Takae Shimada, Mitsuhiro Kadota, Yuki Kawaguchi
  • Publication number: 20190319548
    Abstract: In a power conversion device in a configuration in which a plurality of power converter cells has serially connected outputs and includes a converter and an inverter as components, when a load is light, the cells also operate with a light load, and efficiency is reduced. A power conversion device has a plurality of power converter cells. The outputs of the cells are connected in series. The device has a controller that controls the cells. The cells each have a converter that converts an externally inputted power supply voltage and generates a DC link voltage and an inverter that converts the DC link voltage into an alternating current voltage and outputs the current. The controller stops a converter in some of the cells depending on power supply electric power or load electric power. The inverter continues to operate using a link capacitor as a power supply.
    Type: Application
    Filed: April 10, 2017
    Publication date: October 17, 2019
    Inventors: Mizuki NAKAHARA, Yasuaki NORIMATSU, Takae SHIMADA, Mitsuhiro KADOTA, Yuki KAWAGUCHI
  • Publication number: 20190199100
    Abstract: A power conversion device includes three first power conversion cells each converting input power and outputting the converted power and having input terminals connected in parallel regarding a first power supply and three second power conversion cells each converting input power and outputting the converted power and having input terminals connected in parallel regarding a second power supply, wherein: the power output from the cell and the power output from the cell are combined to output a first phase power; the power output from the cell and the power output from the cell are combined to output a second phase power; and the power output from the cell and the power output from the cell are combined to output a third phase power. The first phase, second phase, and third phase powers are output as the phase powers or inter-line powers of a three-phase system.
    Type: Application
    Filed: October 5, 2016
    Publication date: June 27, 2019
    Inventors: Mitsuhiro KADOTA, Akihiko KANOUDA, Yasuaki NORIMATSU, Takae SHIMADA
  • Publication number: 20190199238
    Abstract: In a power conversion device, a power conversion unit includes a single-phase inverter on a secondary side of a resonant type converter that has an input of a direct current. A power conversion unit group is configured by connecting outputs of the single-phase inverters of a plurality of power conversion units in series. Respective phases of three phase alternate current are formed with the three power conversion unit groups housed in a power conversion device housing. The plurality of power conversion units constituting the power conversion unit group are disposed along a longitudinal direction of the power conversion device housing. The respective three power conversion unit groups are disposed at an upper stage, a middle stage, and a lower stage in a height direction of the power conversion device housing. The power conversion device housing has one end side in the longitudinal direction as output terminals of the three power conversion unit groups.
    Type: Application
    Filed: September 6, 2016
    Publication date: June 27, 2019
    Inventors: Yasuaki NORIMATSU, Akihiko KANOUDA, Yuuichi MABUCHI, Takae SHIMADA, Mitsuhiro KADOTA, Yuki KAWAGUCHI, Mizuki NAKAHARA, Akira YONEKAWA
  • Publication number: 20170093299
    Abstract: In order to reduce the size of an isolation transformer, the present invention provides a power conversion device including: a first inverter unit for obtaining a DC input and giving a high frequency output; an LLC transformer for converting the voltage of the high frequency output of the first inverter unit; a rectifier unit for DC-converting the voltage of the output of the LLC transformer; a second inverter unit for converting the DC output of the rectifier unit into AC; and a control circuit for obtaining the gate power of a semiconductor device configuring the second inverter unit through a power supply transformer for the control circuit that is connected in parallel to the secondary circuit of the LLC transformer.
    Type: Application
    Filed: August 24, 2016
    Publication date: March 30, 2017
    Inventors: Yasuaki NORIMATSU, Akihiko KANODA, Yuichi MABUCHI, Takae SHIMADA, Mitsuhiro KADOTA, Yuki KAWAGUCHI, Akira YONEKAWA