Patents by Inventor Hirokazu Matsui

Hirokazu Matsui 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).

  • Publication number: 20240106322
    Abstract: In a power conversion system, a control circuit has, as its operation modes: a first control mode in which control circuit controls a DC-DC converter at a first drive frequency; a second control mode in which control circuit controls DC-DC converter at a second drive frequency higher than first drive frequency; and a third control mode in which control circuit controls DC-DC converter at a third drive frequency higher than first drive frequency. Control circuit is configured to change operation mode from first control mode into second control mode when detector circuit detects a predetermined change in output voltage while control circuit is operating in first control mode. Control circuit controls DC-DC converter in third control mode in a process of changing, in response to detection of predetermined change, operation mode from first control mode into second control mode before starting to control DC-DC converter in second control mode.
    Type: Application
    Filed: January 22, 2022
    Publication date: March 28, 2024
    Inventors: Hirokazu NAKAMURA, Kohei TSUKAMOTO, Kenichi ASANUMA, Ryoji MATSUI
  • Patent number: 11831265
    Abstract: A motor control device includes a PWM control unit, a carrier frequency setting unit, and a carrier frequency switching calculation unit. The PWM unite generates a signal to drive an inverter by pulse width modulation. The carrier frequency setting unit sets a carrier frequency used for pulse width modulation according to a number of rotations of a motor. The carrier frequency switching calculation unit calculates a frequency switching speed of the carrier frequency and is configured to perform a calculation method. The calculation method includes setting at least one of an emergency mode, a response priority mode, or a fluctuation suppression priority mode in response to various operating conditions.
    Type: Grant
    Filed: November 14, 2019
    Date of Patent: November 28, 2023
    Assignee: Hitachi Astemo, Ltd.
    Inventors: Midori Takaoka, Takafumi Hara, Shigehisa Aoyagi, Hirokazu Matsui, Shigeyuki Nonomura
  • Publication number: 20230198437
    Abstract: A drive device of a synchronous motor includes a power converter that drives the synchronous motor by sequentially applying positive and negative voltages to respective phases of the synchronous motor; a current detection unit that detects a phase current; and a magnetic pole position estimation unit estimating a magnetic pole position of a rotor based on the phase current. The magnetic pole position estimation unit acquires maximum and minimum values of the phase current while the synchronous motor is stopped, calculates a first magnetic pole position from a subtracted value of an absolute value of the maximum and minimum values, calculates a second magnetic pole position from an added value of the absolute value of the maximum and minimum values, discriminates a polarity of a magnet of the rotor, and estimates an initial magnetic pole position of the rotor from the polarity and the second magnetic pole position.
    Type: Application
    Filed: February 5, 2021
    Publication date: June 22, 2023
    Applicant: Hitachi Astemo, Ltd.
    Inventors: Hiroaki SATO, Shigehisa AOYAGI, Shigeyuki NONOMURA, Hirokazu MATSUI
  • Publication number: 20230155534
    Abstract: An inverter control device 200 includes a PWM control unit 220 that generates a PWM pulse for controlling an inverter 100, and a pulse edge control unit 250 that performs pulse edge control for correcting (shifting) a phase of a pulse edge of the PWM pulse generated by the PWM control unit 220. The PWM control unit 220 generates a PWM pulse by using a modulation rate based on a voltage command (Vd*, Vq*). The pulse edge control unit 250 corrects the PWM pulse so that a phase difference between a zero cross point where the modulation wave changes across 0 and a pulse edge of the PWM pulse falls within a predetermined range.
    Type: Application
    Filed: January 22, 2021
    Publication date: May 18, 2023
    Applicant: Hitachi Astemo, Ltd.
    Inventors: Toshiyuki AJIMA, Takafumi HARA, Akihiro ASHIDA, Hirokazu MATSUI, Kiyoshi KURODA
  • Patent number: 11646690
    Abstract: A random value integration unit 175 outputs a random value output from a random value generation unit 174 in a diffusion width Rand output from a diffusion width generation unit 173 by a product of an output of the random value generation unit 174 and an output of the diffusion width generation unit 173. A triangular wave signal generation unit 176 generates a triangular wave signal corresponding to a second carrier frequency fc2 which is obtained by adding the random value output from the random value integration unit 175 to a first carrier frequency fc1 which is an output of a carrier frequency setting unit 171. That is, a frequency obtained by increasing the diffusion width of the first carrier frequency fc1 is used as the second carrier frequency fc2, and the second carrier frequency is used as the carrier frequency.
    Type: Grant
    Filed: September 12, 2019
    Date of Patent: May 9, 2023
    Assignee: HITACHI ASTEMO, LTD.
    Inventors: Takafumi Hara, Midori Takaoka, Toshiyuki Ajima, Hirokazu Matsui, Akihiro Ashida
  • Publication number: 20220247328
    Abstract: An inverter control device 200 includes a current control unit 210 that outputs a voltage commands (Vd*, Vq*), a modulation wave control unit 220 that generates a modulation wave based on the voltage commands (Vd*, Vq*), a pulse generation unit 230 that generates a PWM pulse for controlling an inverter 100 using a modulation wave and a carrier wave of a predetermined frequency, and a pulse shift unit 250 that corrects the phase of the PWM pulse such that the PWM pulse is output in a phase corresponding to a harmonic of a predetermined order of the modulation wave in the near-zero-cross region including the zero-cross point at which the modulation wave changes across 0.
    Type: Application
    Filed: July 31, 2020
    Publication date: August 4, 2022
    Inventors: Toshiyuki AJIMA, Takafumi HARA, Akihiro ASHIDA, Hirokazu MATSUI
  • Publication number: 20220029573
    Abstract: In Steps S54 to S55, when a change rate ??* of a torque command value to a motor 10 is equal to or greater than a predetermined value, a frequency switching speed ?fc of a carrier frequency fc is set based on the number of rotations N of the motor 10 so that a response frequency ?fc of a frequency switching speed ?fc of the carrier frequency fc becomes faster than a response frequency ?ACR of a current control unit 70. In Steps S54 and S56, when the change rate ??* of the torque command value to the motor 10 is less than a predetermined value, the frequency switching speed ?fc of the carrier frequency fc is set based on a torque command value ?* to the motor 10 and the number of rotations N of the motor 10 regardless of the response frequency ?ACR of the current control unit 70.
    Type: Application
    Filed: November 14, 2019
    Publication date: January 27, 2022
    Applicant: HITACHI ASTEMO, LTD.
    Inventors: Midori TAKAOKA, Takafumi HARA, Shigehisa AOYAGI, Hirokazu MATSUI, Shigeyuki NONOMURA
  • Publication number: 20210384859
    Abstract: A random value integration unit 175 outputs a random value output from a random value generation unit 174 in a diffusion width Rand output from a diffusion width generation unit 173 by a product of an output of the random value generation unit 174 and an output of the diffusion width generation unit 173. A triangular wave signal generation unit 176 generates a triangular wave signal corresponding to a second carrier frequency fc2 which is obtained by adding the random value output from the random value integration unit 175 to a first carrier frequency fc1 which is an output of a carrier frequency setting unit 171. That is, a frequency obtained by increasing the diffusion width of the first carrier frequency fc1 is used as the second carrier frequency fc2, and the second carrier frequency is used as the carrier frequency.
    Type: Application
    Filed: September 12, 2019
    Publication date: December 9, 2021
    Applicant: HITACHI ASTEMO, LTD.
    Inventors: Takafumi HARA, Midori TAKAOKA, Toshiyuki AJIMA, Hirokazu MATSUI, Akihiro ASHIDA
  • Patent number: 11001148
    Abstract: To appropriately limit a current output from an inverter to a motor according to a state of a cooling mechanism that cools the motor and the inverter. A motor control unit includes a current command unit configured to calculate current command values (Id*, Iq*) for determining a current to be output to a motor on the basis of an input torque command, a motor lock determination unit configured to determine whether the motor is in a locked state on the basis of a motor rotation speed Nrpm indicating a rotation state of the motor, and a torque command limitation unit configured to limit the current to be output to the motor by limiting the torque command on the basis of a cooling water temperature Tc indicating a state of the cooling mechanism in a case where the motor lock determination unit determines that the motor is in the locked state.
    Type: Grant
    Filed: January 18, 2018
    Date of Patent: May 11, 2021
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Hirokazu Matsui, Atsushi Komuro, Kohei Myoen
  • Patent number: 10987895
    Abstract: Described herein is a roof member or a ceiling member, which is capable of reducing cooling and heating energy consumption by reducing influent and effluent heat amounts between indoor and outdoor environments in such a situation that the indoor temperature is kept constant by use of cooling and heating equipment independently of the outdoor air temperature changes. The disclosed member for roofing or ceiling includes an outdoor-side heat insulating layer (A); an indoor-side heat insulating layer (B); and a heat storage layer between the outdoor-side heat insulating layer (A) and the indoor-side heat insulating layer (B).
    Type: Grant
    Filed: January 9, 2020
    Date of Patent: April 27, 2021
    Assignee: SUMITOMO CHEMICAL COMPANY, LIMITED
    Inventors: Tomoo Hirota, Hirokazu Matsui
  • Patent number: 10982432
    Abstract: Described herein is an exterior wall member capable of reducing cooling and heating energy consumption by reducing influent and effluent heat amounts between indoor and outdoor environments in such a situation that the indoor temperature is kept constant by use of cooling and heating equipment independently of the outdoor air temperature changes, and to provide a construction including the exterior wall member. The disclosed exterior wall member includes an outdoor-side heat insulating layer (A); an indoor-side heat insulating layer (B); and a heat storage layer between the outdoor-side heat insulating layer (A) and the indoor-side heat insulating layer (B).
    Type: Grant
    Filed: January 9, 2020
    Date of Patent: April 20, 2021
    Assignee: SUMITOMO CHEMICAL COMPANY, LIMITED
    Inventors: Tomoo Hirota, Hirokazu Matsui
  • Publication number: 20200224411
    Abstract: Described herein is an exterior wall member capable of reducing cooling and heating energy consumption by reducing influent and effluent heat amounts between indoor and outdoor environments in such a situation that the indoor temperature is kept constant by use of cooling and heating equipment independently of the outdoor air temperature changes, and to provide a construction including the exterior wall member. The disclosed exterior wall member includes an outdoor-side heat insulating layer (A); an indoor-side heat insulating layer (B); and a heat storage layer between the outdoor-side heat insulating layer (A) and the indoor-side heat insulating layer (B).
    Type: Application
    Filed: January 9, 2020
    Publication date: July 16, 2020
    Inventors: Tomoo HIROTA, Hirokazu MATSUI
  • Publication number: 20200223174
    Abstract: Described herein is a roof member or a ceiling member, which is capable of reducing cooling and heating energy consumption by reducing influent and effluent heat amounts between indoor and outdoor environments in such a situation that the indoor temperature is kept constant by use of cooling and heating equipment independently of the outdoor air temperature changes. The disclosed member for roofing or ceiling includes an outdoor-side heat insulating layer (A); an indoor-side heat insulating layer (B); and a heat storage layer between the outdoor-side heat insulating layer (A) and the indoor-side heat insulating layer (B).
    Type: Application
    Filed: January 9, 2020
    Publication date: July 16, 2020
    Inventors: Tomoo HIROTA, Hirokazu MATSUI
  • Publication number: 20200021220
    Abstract: To appropriately limit a current output from an inverter to a motor according to a state of a cooling mechanism that cools the motor and the inverter. A motor control unit includes a current command unit configured to calculate current command values (Id*, Iq*) for determining a current to be output to a motor on the basis of an input torque command, a motor lock determination unit configured to determine whether the motor is in a locked state on the basis of a motor rotation speed Nrpm indicating a rotation state of the motor, and a torque command limitation unit configured to limit the current to be output to the motor by limiting the torque command on the basis of a cooling water temperature Tc indicating a state of the cooling mechanism in a case where the motor lock determination unit determines that the motor is in the locked state.
    Type: Application
    Filed: January 18, 2018
    Publication date: January 16, 2020
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Hirokazu MATSUI, Atsushi KOMURO, Kohei MYOEN
  • Patent number: 10355630
    Abstract: An object of the invention is to correct a variation of a gain of a current sensor without causing an increase in size and a high cost of an inverter control device. An inverter control device according to the invention includes a 3-phase/dq-axis conversion unit which converts the output current detected by a current sensor into a dq-axis current and a gain adjustment unit which adjusts a detection gain of the current sensor for each phase. In a case where a current value of a secondary harmonic component contained in the dq-axis current is equal to or more than a predetermined threshold, the gain adjustment unit corrects the gain of the current sensor such that the current value of the secondary harmonic component becomes less than the threshold.
    Type: Grant
    Filed: April 28, 2016
    Date of Patent: July 16, 2019
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Hiroshi Tamura, Hiroyuki Yamada, Shigeyuki Nonomura, Hirokazu Matsui
  • Patent number: 10254473
    Abstract: A light-emitting panel of the present invention has a LED, a surface light-emitting member, a light source holder, and a holder supporting portion. The surface light-emitting member has a rectangular plate shape and at least one surface of front and back surfaces is surface-emitted by entering light from the light source into an incident edge. The light source holder holds the LED such that a light exit of the light source is arranged toward the incident edge. The holder supporting portion is fixed to the surface light-emitting member and hold detachably the light source holder. The light-emitting panel of the present invention can reduce effects of the light source due to thermal expansion of the surface light-emitting member, and easily replace the light source.
    Type: Grant
    Filed: January 23, 2015
    Date of Patent: April 9, 2019
    Assignee: MEITAKU INDUSTRY CO., LTD.
    Inventor: Hirokazu Matsui
  • Publication number: 20180138845
    Abstract: An object of the invention is to correct a variation of a gain of a current sensor without causing an increase in size and a high cost of an inverter control device. An inverter control device according to the invention includes a 3-phase/dq-axis conversion unit which converts the output current detected by a current sensor into a dq-axis current and a gain adjustment unit which adjusts a detection gain of the current sensor for each phase. In a case where a current value of a secondary harmonic component contained in the dq-axis current is equal to or more than a predetermined threshold, the gain adjustment unit corrects the gain of the current sensor such that the current value of the secondary harmonic component becomes less than the threshold.
    Type: Application
    Filed: April 28, 2016
    Publication date: May 17, 2018
    Inventors: Hiroshi TAMURA, Hiroyuki YAMADA, Shigeyuki NONOMURA, Hirokazu MATSUI
  • Patent number: 9932459
    Abstract: A resin composition is provided for a sliding member. The composition contains an amorphous resin, flake graphite, and a carbon fiber. The content of the flake graphite is 5 to 40 parts by mass relative to 100 parts by mass of the amorphous resin, and the content of the carbon fiber is 5 to 60 parts by mass relative to 100 parts by mass of the amorphous resin.
    Type: Grant
    Filed: September 29, 2014
    Date of Patent: April 3, 2018
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Hidehiro Kotaka, Hirokazu Matsui, Mitsuo Maeda
  • Publication number: 20170212299
    Abstract: A surface lighting assembly emitting light from a surface by making light from a light source incident to an incident end surface of a light guide plate is provided. The surface lighting assembly has a laminated body overlapping a diffuser sheet and an opaque plate on a surface of the light guide plate, a frame member arranging along an end edge of the laminated body, and a fastening member fixing the laminated body and the frame member in the thickness direction. The frame member is formed with U-shaped in cross section. In the first and second side surfaces, through holes are formed so as to insert the fastening member and guide it along the longitudinal direction of the frame member.
    Type: Application
    Filed: July 17, 2015
    Publication date: July 27, 2017
    Inventors: Hirokazu Matsui, Katsuhiro Matsui, Tomohiko Masuda
  • Publication number: 20170115444
    Abstract: A light-emitting panel of the present invention has a LED, a surface light-emitting member, a light source holder, and a holder supporting portion. The surface light-emitting member has a rectangular plate shape and at least one surface of front and back surfaces is surface-emitted by entering light from the light source into an incident edge. The light source holder holds the LED such that a light exit of the light source is arranged toward the incident edge. The holder supporting portion is fixed to the surface light-emitting member and hold detachably the light source holder. The light-emitting panel of the present invention can reduce effects of the light source due to thermal expansion of the surface light-emitting member, and easily replace the light source.
    Type: Application
    Filed: January 23, 2015
    Publication date: April 27, 2017
    Inventor: Hirokazu MATSUI