Patents by Inventor Akio Toba

Akio Toba 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: 12191245
    Abstract: A semiconductor device includes: an insulated circuit substrate including first and second conductive layers on a top surface side; a first semiconductor chip mounted on the first conductive layer; a second semiconductor chip mounted on the second conductive layer; a printed circuit board including a first lower-side wiring layer arranged to be opposed to the first semiconductor chip, and a second lower-side wiring layer arranged to be opposed to the second semiconductor chip, the printed circuit board being provided with a curved part curved toward the insulated circuit substrate; a first connection member arranged to connect the first semiconductor chip with the first lower-side wiring layer; a second connection member arranged to connect the second semiconductor chip with the second lower-side wiring layer; and a third connection member arranged to connect the first conductive layer with the second lower-side wiring layer at the curved part.
    Type: Grant
    Filed: April 28, 2022
    Date of Patent: January 7, 2025
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Motohito Hori, Yoshinari Ikeda, Akio Toba, Michio Tamate, Ikuya Sato
  • Patent number: 12176817
    Abstract: A power converter includes a capacitor and a substrate on which a plurality of switching elements for power conversion are mounted. The power converter includes a cooler for cooling the plurality of switching elements and a housing that accommodates the capacitor, the substrate, and the cooler. The power converter includes a power connector exposed from the housing and an output connector exposed from the housing. The power converter includes a plurality of lines that include a plurality of power lines each electrically connected to the capacitor, given switching elements, and the power connector. The plurality of lines include a plurality of output lines each electrically connected to given switching elements and the output connector. At least one among the plurality of lines is a line that includes a conductive pattern formed on the substrate.
    Type: Grant
    Filed: December 26, 2023
    Date of Patent: December 24, 2024
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Yuji Suzuki, Motohito Hori, Akio Toba, Ikuya Sato, Yasuhito Tanaka, Masamichi Iwasaki, Masaaki Ajima, Nobuaki Ohguri
  • Publication number: 20240128880
    Abstract: A power converter includes a capacitor and a substrate on which a plurality of switching elements for power conversion are mounted. The power converter includes a cooler for cooling the plurality of switching elements and a housing that accommodates the capacitor, the substrate, and the cooler. The power converter includes a power connector exposed from the housing and an output connector exposed from the housing. The power converter includes a plurality of lines that include a plurality of power lines each electrically connected to the capacitor, given switching elements, and the power connector. The plurality of lines include a plurality of output lines each electrically connected to given switching elements and the output connector. At least one among the plurality of lines is a line that includes a conductive pattern formed on the substrate.
    Type: Application
    Filed: December 26, 2023
    Publication date: April 18, 2024
    Inventors: Yuji SUZUKI, Motohito HORI, Akio TOBA, Ikuya SATO, Yasuhito TANAKA, Masamichi IWASAKI, Masaaki AJIMA, Nobuaki OHGURI
  • Patent number: 11949338
    Abstract: A power converter includes a positive busbar electrically connected to a positive terminal and the first capacitor electrode, and includes a negative busbar electrically connected to a negative terminal and the second capacitor electrode. The power converter includes output busbars each electrically connected to a given output terminal among multiple output terminals, a given high-side switching element among a plurality of high-side switching elements, and a given low-side switching element among a plurality of low-side switching elements. The power converter includes a cooler that cools the high-side switching elements and the low-side switching elements. The power converter includes a housing that accommodates a supply tube and a discharge tube. The positive terminal, the negative terminal, the output terminals, the inlet port, and the outlet port are exposed on the housing. The inlet port, the outlet port, the supply tube, and the discharge tube are separate members from the housing.
    Type: Grant
    Filed: February 23, 2022
    Date of Patent: April 2, 2024
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Yuji Suzuki, Motohito Hori, Akio Toba, Ikuya Sato, Yasuhito Tanaka, Masamichi Iwasaki, Masaaki Ajima, Nobuaki Ohguri
  • Patent number: 11894774
    Abstract: A power converter includes a capacitor and a substrate on which a plurality of switching elements for power conversion are mounted. The power converter includes a cooler for cooling the plurality of switching elements and a housing that accommodates the capacitor, the substrate, and the cooler. The power converter includes a power connector exposed from the housing and an output connector exposed from the housing. The power converter includes a plurality of lines that include a plurality of power lines each electrically connected to the capacitor, given switching elements, and the power connector. The plurality of lines include a plurality of output lines each electrically connected to given switching elements and the output connector. At least one among the plurality of lines is a line that includes a conductive pattern formed on the substrate.
    Type: Grant
    Filed: February 23, 2022
    Date of Patent: February 6, 2024
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Yuji Suzuki, Motohito Hori, Akio Toba, Ikuya Sato, Yasuhito Tanaka, Masamichi Iwasaki, Masaaki Ajima, Nobuaki Ohguri
  • Publication number: 20230170818
    Abstract: A power conversion system in which a converter and an inverter are coupled to each other via a DC coupling unit that has an inductance component is provided. A switching frequency of each of the converter and the inverter is set to be the same and the switching frequency is set to be higher than a resonance frequency of a resonance circuit that includes a first capacitor, a second capacitor, and the DC coupling unit such as a cable. A switching operation of at least one of the converter or the inverter is controlled such that phases of predetermined components of voltage ripples, at the first capacitor and the second capacitor, that are respectively generated by switching operations of the converter and the inverter are substantially matched.
    Type: Application
    Filed: January 24, 2023
    Publication date: June 1, 2023
    Inventor: Akio TOBA
  • Publication number: 20220406690
    Abstract: A semiconductor device includes: an insulated circuit substrate including first and second conductive layers on a top surface side; a first semiconductor chip mounted on the first conductive layer; a second semiconductor chip mounted on the second conductive layer; a printed circuit board including a first lower-side wiring layer arranged to be opposed to the first semiconductor chip, and a second lower-side wiring layer arranged to be opposed to the second semiconductor chip, the printed circuit board being provided with a curved part curved toward the insulated circuit substrate; a first connection member arranged to connect the first semiconductor chip with the first lower-side wiring layer; a second connection member arranged to connect the second semiconductor chip with the second lower-side wiring layer; and a third connection member arranged to connect the first conductive layer with the second lower-side wiring layer at the curved part.
    Type: Application
    Filed: April 28, 2022
    Publication date: December 22, 2022
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Motohito HORI, Yoshinari IKEDA, Akio TOBA, Michio TAMATE, Ikuya SATO
  • Publication number: 20220181980
    Abstract: A power converter includes a capacitor and a substrate on which a plurality of switching elements for power conversion are mounted. The power converter includes a cooler for cooling the plurality of switching elements and a housing that accommodates the capacitor, the substrate, and the cooler. The power converter includes a power connector exposed from the housing and an output connector exposed from the housing. The power converter includes a plurality of lines that include a plurality of power lines each electrically connected to the capacitor, given switching elements, and the power connector. The plurality of lines include a plurality of output lines each electrically connected to given switching elements and the output connector. At least one among the plurality of lines is a line that includes a conductive pattern formed on the substrate.
    Type: Application
    Filed: February 23, 2022
    Publication date: June 9, 2022
    Inventors: Yuji SUZUKI, Motohito HORI, Akio TOBA, Ikuya SATO, Yasuhito TANAKA, Masamichi IWASAKI, Masaaki AJIMA, Nobuaki OHGURI
  • Publication number: 20220181981
    Abstract: A power converter includes a positive busbar electrically connected to a positive terminal and the first capacitor electrode, and includes a negative busbar electrically connected to a negative terminal and the second capacitor electrode. The power converter includes output busbars each electrically connected to a given output terminal among multiple output terminals, a given high-side switching element among a plurality of high-side switching elements, and a given low-side switching element among a plurality of low-side switching elements. The power converter includes a cooler that cools the high-side switching elements and the low-side switching elements. The power converter includes a housing that accommodates a supply tube and a discharge tube. The positive terminal, the negative terminal, the output terminals, the inlet port, and the outlet port are exposed on the housing. The inlet port, the outlet port, the supply tube, and the discharge tube are separate members from the housing.
    Type: Application
    Filed: February 23, 2022
    Publication date: June 9, 2022
    Inventors: Yuji SUZUKI, Motohito HORI, Akio TOBA, Ikuya SATO, Yasuhito TANAKA, Masamichi IWASAKI, Masaaki AJIMA, Nobuaki OHGURI
  • Patent number: 10778116
    Abstract: A three-phase inverter includes three series circuits that are connected in parallel to a capacitor connected in parallel to a DC voltage source. Each of the three series circuits includes two semiconductor switching elements connected in series. A connection point between the two semiconductor switching elements is used as an AC output terminal for each phase. The three-phase inverter generates PWM pulses of three phases including a PWM pulse of one phase, whose pulse width of a positive side pulse in one switching cycle is the largest, and including PWM pulses of the other two phases such that a positional relationship between positive side pulses of the other two phases is a positional relationship in which an overlapping range on a time axis is smaller as compared with a state in which a positive side pulse of one phase encompasses a positive side pulse of the other pulse.
    Type: Grant
    Filed: February 19, 2019
    Date of Patent: September 15, 2020
    Assignees: National University Corporation Nagaoka University of Technology, FUJI ELECTRIC CO., LTD.
    Inventors: Junichi Itoh, Koroku Nishizawa, Akio Toba, Akihiro Odaka
  • Patent number: 10720805
    Abstract: An embedded permanent magnet type motor, which has one pole configured of two permanent magnets and has a plurality of poles of permanent magnets embedded in a rotor, includes a rotor whose magnet embedding holes communicate with a rotor outer periphery. The rotor has between adjacent poles a q-axis projection projecting in a direction away from a rotor rotation center. The magnet embedding holes are disposed so as to form an inverted V shape. An outer peripheral edge portion on the outer side of the permanent magnets has a curvature radius smaller than the distance from a rotation center axis to a rotor outermost peripheral portion. The outer peripheral edge portion is provided with permanent magnet positioning projections which restrain a movement of the permanent magnets toward between adjacent poles.
    Type: Grant
    Filed: June 8, 2015
    Date of Patent: July 21, 2020
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Toshiharu Mochida, Akio Toba, Hideki Ohguchi, Hiroshi Shimada, Takeyuki Kobayashi
  • Patent number: 10700630
    Abstract: A control method of an inverter for outputting polyphase alternate-current electrical power is provided. In the control method, modified PWM pulses of respective phases for controlling semiconductor switching elements of the inverter are generated, based on an output of a counter common to the respective phases. Each of the modified PWM pulses is configured such that a total pulse width, in a period corresponding to one or more cycles of a carrier, is substantially equal to a total pulse width of an assumed PWM pulse which is obtained by comparing, with the carrier, a time average value of an output voltage of the corresponding phase in the period. Further, at least one of a generation timing and a generation frequency of at least one of the modified PWM pulses is changed from the assumed PWM pulse.
    Type: Grant
    Filed: November 5, 2018
    Date of Patent: June 30, 2020
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Akio Toba, Akihiro Odaka, Hidetoshi Umida
  • Patent number: 10651776
    Abstract: A control method of an inverter for outputting polyphase alternate-current electrical power is provided. In the control method, modified PWM pulses of respective phases for controlling semiconductor switching elements of the inverter are generated, based on an output of a counter common to the respective phases. Each of the modified PWM pulses is configured such that a total pulse width, in a period corresponding to one or more cycles of a carrier, is substantially equal to a total pulse width of an assumed PWM pulse which is obtained by comparing, with the carrier, a time average value of an output voltage of the corresponding phase in the period. Further, at least one of a generation timing and a generation frequency of at least one of the modified PWM pulses is changed from the assumed PWM pulse.
    Type: Grant
    Filed: November 5, 2018
    Date of Patent: May 12, 2020
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Akio Toba, Akihiro Odaka, Hidetoshi Umida
  • Publication number: 20190334454
    Abstract: A three-phase inverter includes three series circuits that are connected in parallel to a capacitor connected in parallel to a DC voltage source. Each of the three series circuits includes two semiconductor switching elements connected in series. A connection point between the two semiconductor switching elements is used as an AC output terminal for each phase. The three-phase inverter generates PWM pulses of three phases including a PWM pulse of one phase, whose pulse width of a positive side pulse in one switching cycle is the largest, and including PWM pulses of the other two phases such that a positional relationship between positive side pulses of the other two phases is a positional relationship in which an overlapping range on a time axis is smaller as compared with a state in which a positive side pulse of one phase encompasses a positive side pulse of the other pulse.
    Type: Application
    Filed: February 19, 2019
    Publication date: October 31, 2019
    Inventors: Junichi ITOH, Koroku NISHIZAWA, Akio TOBA, Akihiro ODAKA
  • Publication number: 20190089286
    Abstract: A control method of an inverter for outputting polyphase alternate-current electrical power is provided. In the control method, modified PWM pulses of respective phases for controlling semiconductor switching elements of the inverter are generated, based on an output of a counter common to the respective phases. Each of the modified PWM pulses is configured such that a total pulse width, in a period corresponding to one or more cycles of a carrier, is substantially equal to a total pulse width of an assumed PWM pulse which is obtained by comparing, with the carrier, a time average value of an output voltage of the corresponding phase in the period. Further, at least one of a generation timing and a generation frequency of at least one of the modified PWM pulses is changed from the assumed PWM pulse.
    Type: Application
    Filed: November 5, 2018
    Publication date: March 21, 2019
    Inventors: Akio TOBA, Akihiro ODAKA, Hidetoshi UMIDA
  • Patent number: 10195949
    Abstract: A charger, in one possible configuration, has an AC/DC converter that converts alternating current power supplied from an external alternating current power supply into direct current power and outputs the direct current power, a DC/DC converter that transforms the direct current power output by the AC/DC converter and supplies the transformed direct current power to a vehicle-mounted battery, and a safety control unit that forcibly stops the DC/DC converter with detection of an occurrence of a fault during charging of the vehicle-mounted battery as a trigger, and subsequently causes the AC/DC converter to stop normally.
    Type: Grant
    Filed: June 10, 2016
    Date of Patent: February 5, 2019
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Osamu Takei, Akio Toba, Yasuaki Hachisu, Masakazu Gekinozu, Hiroji Nishida
  • Patent number: 10158265
    Abstract: An embedded permanent magnet type motor, which has one pole configured of two permanent magnets and has a plurality of poles of permanent magnets embedded in a rotor, includes a rotor whose magnet embedding holes communicate with a rotor outer periphery. The rotor has, between adjacent poles, a q-axis projection projecting in a direction away from a rotor rotation center. The magnet embedding holes are disposed so as to form an inverted V shape. An outer peripheral edge portion on the outer side of the permanent magnets has a curvature radius smaller than the distance from a rotation center axis to a rotor outermost peripheral portion. Circular intermediate plates of an outside diameter larger than the outside diameter of rotor steel plates are provided in intermediate positions in the rotor in a rotor rotation axis direction.
    Type: Grant
    Filed: September 10, 2015
    Date of Patent: December 18, 2018
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Toshiharu Mochida, Akio Toba, Hiroshi Shimada, Hirofumi Nishimura
  • Patent number: 9843278
    Abstract: Aspects of a power conversion system can include a capacitor which stores direct current power, an inverter, and a pair of direct current terminals of which are connected to two ends of the capacitor and to the alternating current terminals of which an alternating current motor acting as a load is connected. Also included can be an upper and lower arm portion of which the connection point of semiconductor switches connected in series is connected to the neutral point of the motor, a direct current power source connected in parallel to the upper and lower arm portion and a switch connected between one of the direct current terminals of the inverter and one end of the upper and lower arm portion. The other direct current terminal of the inverter can be connected to the other end of the upper and lower arm portion.
    Type: Grant
    Filed: April 22, 2015
    Date of Patent: December 12, 2017
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventor: Akio Toba
  • Patent number: 9787226
    Abstract: When the current flowing through each electric terminal of an AC motor 21 reaches the vicinity of zero, an operation putting the electric terminals of the AC motor 21 into an opened state, or putting an electric terminal into a conductive state via a reflux diode inside an inverter 11, is carried out. Herein, as an operation such that the current flowing through each electric terminal reaches the vicinity of zero, the electric terminals are short-circuited by all upper arm or lower arm switching elements of the inverter 11 being turned on. By so doing, a flow of electromagnetic energy of a reactance component of the AC motor 21, from the AC motor 21 into the inverter 11 side when the drive of the inverter 11 is stopped, is prevented or suppressed. As a result of this, an overvoltage or overcurrent is prevented.
    Type: Grant
    Filed: August 12, 2014
    Date of Patent: October 10, 2017
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventor: Akio Toba
  • Patent number: 9595908
    Abstract: A method for a power conversion apparatus to drive an electric motor using a power semiconductor device. The method includes detecting or estimating a temperature of the power semiconductor device to thereby obtain a detected or estimated temperature value, adjusting a torque command of the electric motor, so that the temperature of the power semiconductor device matches a preset temperature when the detected or estimated temperature value is equal to or higher than the preset temperature, and controlling the power semiconductor device using the adjusted torque command.
    Type: Grant
    Filed: September 4, 2015
    Date of Patent: March 14, 2017
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Akihiro Odaka, Akio Toba