Patents by Inventor Keiichi Enoki

Keiichi Enoki 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: 10050569
    Abstract: An inverter control device that controls a multiple of inverters configured to use the same positive and negative direct current voltage bus lines connected to a power supply and driving a corresponding multiple of motors, the inverter control device including smoothing control means that controls an inverter outflow current so that voltage of the power supply is smoothed by a smoothing capacitor connected to the positive and negative direct current voltage bus lines, and two-phase modulation operation means that fixes a predetermined one phase of a three-phase modulated wave at either a maximum voltage or minimum voltage the inverter can output determined by a voltage between the positive and negative direct current voltage bus lines, and calculates a modulated wave that causes the other two phases to switch.
    Type: Grant
    Filed: February 14, 2017
    Date of Patent: August 14, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Shingo Harada, Keiichi Enoki, Yasukazu Murata, Masutaka Watanabe, Yoshimasa Nishijima
  • Patent number: 10027265
    Abstract: An inverter control device and inverter control method are such that, when there is a possibility of induction voltage caused by a multi-phase motor exceeding a breakdown voltage of a switching element of an inverter, two of three phases are first interrupted at an appropriate timing in order to restrict induction voltage when shifting from a three-phase short circuit to an all-phase interruption, after which a shift is made to an all-phase interruption at a timing at which currents of the three phases reach the vicinity of zero, whereby a leap in a direct current bus voltage is restricted.
    Type: Grant
    Filed: June 29, 2017
    Date of Patent: July 17, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Shingo Harada, Keiichi Enoki, Masutaka Watanabe, Yoshimasa Nishijima, Yasukazu Murata, Michitaka Fujiwara
  • Publication number: 20180154887
    Abstract: A temperature detection condition of a temperature detection unit used in a motor system is determined by: obtaining a phase current value flowing through a motor device and obtaining a temperature detection value; calculating, as an integrated phase current value, at least one of a first integrated phase current value, which is obtained by integrating an amount by which the phase current value exceeds a first phase current threshold, and a second integrated phase current value, which is obtained by integrating an amount by which the phase current value is smaller than a second phase current threshold that is equal to or smaller than the first phase current threshold; and determining an amount of variation in the temperature detection value detected by the temperature detection unit following the start of determination of the temperature detection condition and an amount of variation in the calculated integrated phase current value.
    Type: Application
    Filed: November 13, 2017
    Publication date: June 7, 2018
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yasukazu MURATA, Keiichi ENOKI, Masutaka WATANABE, Yoshimasa NISHIJIMA, Shingo HARADA
  • Publication number: 20180138844
    Abstract: An inverter control device and inverter control method are such that, when there is a possibility of induction voltage caused by a multi-phase motor exceeding a breakdown voltage of a switching element of an inverter, two of three phases are first interrupted at an appropriate timing in order to restrict induction voltage when shifting from a three-phase short circuit to an all-phase interruption, after which a shift is made to an all-phase interruption at a timing at which currents of the three phases reach the vicinity of zero, whereby a leap in a direct current bus voltage is restricted.
    Type: Application
    Filed: June 29, 2017
    Publication date: May 17, 2018
    Applicant: Mitsubishi Electric Corporation
    Inventors: Shingo HARADA, Keiichi ENOKI, Masutaka WATANABE, Yoshimasa NISHIJIMA, Yasukazu MURATA, Michitaka FUJIWARA
  • Publication number: 20180123493
    Abstract: A motor control device having a motor temperature sensor for detecting a magnet temperature of the motor, a magnet magnetic flux calculation section that calculates a magnet magnetic flux of the motor corresponding to the magnet temperature of the motor, a current combination candidate calculating section that calculates a d-q axis current combination candidate that minimizes the input current of the inverter within a voltage limit ellipse determined by a value that can be output by a voltage of a power supply of the motor, and a d-q axis current search section that searches the d-q axis current that minimizes the input current of the inverter within the range of the combination candidate of the d-q axis currents when the d-q axis current of the motor moves on a voltage limiting ellipse by automatic weakening flux control.
    Type: Application
    Filed: June 22, 2015
    Publication date: May 3, 2018
    Applicant: Mitsubishi Electric Corporation
    Inventors: Shingo HARADA, Keiichi ENOKI, Yasukazu MURATA, Masutaka WATANABE, Yoshimasa NISHIJIMA
  • Publication number: 20180006593
    Abstract: An AC-rotating-electric-machine control apparatus includes two or more electric-power conversion circuits that control respective voltages to be applied to the two or more groups of multi-phase armature windings, for each of the two or more groups of multi-phase armature windings; each of the two or more electric-power conversion circuits has two or more switching devices for opening or closing the corresponding group of multi-phase armature windings, for each of the phases; the two or more switching devices are switching-controlled in such a way that opening operation or duty control can be applied to the corresponding group of multi-phase armature windings.
    Type: Application
    Filed: May 11, 2015
    Publication date: January 4, 2018
    Applicant: Mitsubishi Electric Corporation
    Inventors: Masutaka WATANABE, Keiichi ENOKI, Yasukazu MURATA, Yoshimasa NISHIJIMA, Shingo HARADA
  • Patent number: 9859836
    Abstract: By providing a configuration for calculating motor control constants to be set in a motor control apparatus automatically on the basis of a target response time constant obtained from a target response time constant input unit, waveform parameters obtained from a waveform parameter input unit, a normalized time constant obtained from a normalized time constant calculation unit, and a motor load inertia obtained from a motor load inertia input unit, it is possible to obtain a motor control constant calculation device that can determine appropriate motor control constants for obtaining a desired response characteristic by automatic calculation while avoiding variation and an increase in the number of steps due to differences in the abilities of users.
    Type: Grant
    Filed: May 13, 2014
    Date of Patent: January 2, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kazuto Yokoyama, Masahiro Iezawa, Keiichi Enoki, Yasufumi Ogawa, Kotaro Nakano
  • Patent number: 9845089
    Abstract: The control device for a hybrid vehicle includes: a mechanical power source; an electric motor to be used when the mechanical power source is started; a first clutch arranged between the mechanical power source and a first transmission mechanism including a plurality of gear shift stages; a second clutch arranged between the mechanical power source and a second transmission mechanism including a plurality of gear shift stages; an electrical power source coupled to an input shaft of the first transmission mechanism; and a control unit for controlling a torque of at least one of the second clutch or the electric motor so as to compensate a braking force decreased upon a gear shift in the electrical power source when a gear shift request for shifting the gear shift stage of the first transmission mechanism is made during a regeneration travel of the electrical power source.
    Type: Grant
    Filed: April 23, 2013
    Date of Patent: December 19, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kotaro Nakano, Keiichi Enoki, Nobuhide Mori, Hiroyuki Kobayashi, Yasufumi Ogawa
  • Publication number: 20170279383
    Abstract: An inverter control device that controls a multiple of inverters configured to use the same positive and negative direct current voltage bus lines connected to a power supply and driving a corresponding multiple of motors, the inverter control device including smoothing control means that controls an inverter outflow current so that voltage of the power supply is smoothed by a smoothing capacitor connected to the positive and negative direct current voltage bus lines, and two-phase modulation operation means that fixes a predetermined one phase of a three-phase modulated wave at either a maximum voltage or minimum voltage the inverter can output determined by a voltage between the positive and negative direct current voltage bus lines, and calculates a modulated wave that causes the other two phases to switch.
    Type: Application
    Filed: February 14, 2017
    Publication date: September 28, 2017
    Applicant: Mitsubishi Electric Corporation
    Inventors: Shingo HARADA, Keiichi ENOKI, Yasukazu MURATA, Masutaka WATANABE, Yoshimasa NISHIJIMA
  • Publication number: 20170264229
    Abstract: MCU (2001) determines whether at least one of double three-phase inverter (2030) or battery (2002) has a failure, or battery (2002) is fully charged, and switches control to be performed in inverter (2030) between all-phase shut off and three-phase short circuit based on a motor rotation speed of double three-phase motor (2050) when MCU (2001) determines that any one of inverter (2030) and battery (2002) has a failure, or battery (2002) is fully charged. Battery (2002) and inverter (2030) can be protected when current is inhibited from flowing from motor (2050) to battery (2002) due to a failure of inverter (2030) or battery (2002).
    Type: Application
    Filed: August 29, 2016
    Publication date: September 14, 2017
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yasukazu MURATA, Keiichi ENOKI, Masutaka WATANABE, Shingo HARADA, Yoshimasa NISHIJIMA
  • Patent number: 9688280
    Abstract: In order to provide a traction control device capable of preventing an initial slip at a start, the traction control device includes a drive power source outputting drive power to a drive wheel of a vehicle; a vehicle speed sensor detecting the wheel speed of a non-drive wheel of the vehicle; and target restricted speed generating means for generating a target restricted speed for the vehicle by determining the state of a road surface from target drive torque of the vehicle, the wheel speed of the non-drive wheel, and a signal indicating the extent of operation of an accelerator by a driver. The target restricted speed generated by the target restricted speed generating means is switched stepwise in a speed region where the speed of the drive wheel is not detected in correspondence with a control mode that is classified according to the slipperiness of a road surface.
    Type: Grant
    Filed: October 31, 2013
    Date of Patent: June 27, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventors: Hiroyuki Kobayashi, Masahiro Iezawa, Keiichi Enoki, Nobuhide Mori, Yasufumi Ogawa, Kotaro Nakano
  • Patent number: 9692351
    Abstract: This invention provides a protective device for a vehicle inverter, with which an inverter element can be protected from overheating while preventing a reduction in drivability. The protective device for a vehicle inverter includes a maximum element temperature calculation unit that calculates a maximum element temperature among respective element temperatures of the inverter, and an element temperature output limit coefficient calculation unit that calculates an output limit value corresponding to the maximum element temperature, sets a current output limit value as a current output limit coefficient when the current output limit value is smaller than a preceding output limit coefficient, and sets, as the current output limit coefficient, a value obtained by adding a predetermined value determined in advance to the preceding output limit coefficient when the current output limit value equals or exceeds the preceding output limit coefficient.
    Type: Grant
    Filed: November 7, 2013
    Date of Patent: June 27, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventor: Keiichi Enoki
  • Patent number: 9641107
    Abstract: A motor controller for an electric vehicle sufficiently reduces vibration components caused by torque ripples passing through a resonance frequency of a vehicle body. The motor controller includes motor torque setting means for generating a first torque command, based on vehicle information, rotation position detection means for detecting a rotation position of the motor, rotation speed calculation means for calculating a rotation speed from a rotation position signal, a high-pass filter that extracts an AC signal component of a rotation speed signal, and a resonance suppression gain circuit that outputs a resonance suppression signal. A signal in which the resonance suppression signal is added to or subtracted from the first torque command is used as a second torque command so as to perform drive control for the motor.
    Type: Grant
    Filed: October 15, 2012
    Date of Patent: May 2, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventors: Keiichi Enoki, Masahiro Iezawa, Nobuhide Mori, Yasufumi Ogawa, Hiroyuki Kobayashi
  • Publication number: 20170111004
    Abstract: By providing a configuration for calculating motor control constants to be set in a motor control apparatus automatically on the basis of a target response time constant obtained from a target response time constant input unit, waveform parameters obtained from a waveform parameter input unit, a normalized time constant obtained from a normalized time constant calculation unit, and a motor load inertia obtained from a motor load inertia input unit, it is possible to obtain a motor control constant calculation device that can determine appropriate motor control constants for obtaining a desired response characteristic by automatic calculation while avoiding variation and an increase in the number of steps due to differences in the abilities of users.
    Type: Application
    Filed: May 13, 2014
    Publication date: April 20, 2017
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kazuto YOKOYAMA, Masahiro IEZAWA, Keiichi ENOKI, Yasufumi OGAWA, Kotaro NAKANO
  • Patent number: 9628017
    Abstract: In order to highly accurately estimate a temperature of a permanent magnet to be used for a rotor of a motor, provided is a motor control device for a vehicle including a motor as a drive power source, in which an estimation mode setting section sets, when a predetermined condition for estimating the temperature of the permanent magnet to be used for the rotor of the motor is established under a state in which the motor generates drive power to run the vehicle, a current flowing through the motor to 0, and a permanent magnet temperature estimation section estimates the temperature of the permanent magnet based on an induced voltage of the motor in a period during which the current flowing through the motor is 0.
    Type: Grant
    Filed: October 11, 2012
    Date of Patent: April 18, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventors: Yasufumi Ogawa, Keiichi Enoki, Nobuhide Mori, Hiroyuki Kobayashi
  • Patent number: 9623753
    Abstract: A vehicle control part includes: a vehicle stop determination part for determining whether or not the vehicle is stopped; a clutch control part for disengaging the clutch when stop of the vehicle is determined; a motor control part for driving the motor so as to drive the oil circulation part after the clutch is disengaged; and a motor magnet temperature estimation part for detecting an inducted voltage generated by drive of the motor, and estimating a magnet temperature of the motor from the detected induced voltage of the motor. The motor control part continues the drive of the motor when the estimated magnet temperature of the motor is higher than a predetermined reference temperature at which the motor needs to be cooled, and stops the drive of the motor when the magnet temperature of the motor is equal to or lower than the predetermined reference temperature.
    Type: Grant
    Filed: April 11, 2013
    Date of Patent: April 18, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventors: Nobuhide Mori, Keiichi Enoki, Hiroyuki Kobayashi, Yasufumi Ogawa, Kotaro Nakano
  • Patent number: 9561738
    Abstract: A control apparatus of an electrically-driven vehicle controls an electrically-driven vehicle including a motor transmitting a drive force to wheels, an inverter driving the motor, and a battery supplying power to the inverter. The control apparatus includes battery storage amount estimation means for estimating a storage amount of the battery and motor rotation speed detection means for detecting a rotation speed of the motor. Output terminals of the inverter are short-circuited when the rotation speed of the motor reaches or exceeds a predetermined rotation speed while the storage amount estimated by the battery storage amount estimation means is equal to or greater than a predetermined amount.
    Type: Grant
    Filed: October 26, 2011
    Date of Patent: February 7, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventors: Yasufumi Ogawa, Keiichi Enoki, Takuya Tamura
  • Publication number: 20160325748
    Abstract: An object of this invention is to obtain a vehicle control apparatus with which departure over a bump can be identified accurately, and when departure over the bump is identified, a required driving force can be controlled to an appropriate value. A departure over bump identification unit identifies departure over a bump, in which an electric vehicle travels over the bump in order to depart, when a motor rotation speed is equal to or lower than a predetermined first rotation speed and an accelerator pedal depression amount remains at or above a predetermined accelerator pedal depression amount continuously for a predetermined first period, and a drive control unit sets a required driving force of a motor at zero, regardless of the accelerator pedal depression amount, and then increases the required driving force at a constant speed, when departure over the bump is identified.
    Type: Application
    Filed: March 13, 2014
    Publication date: November 10, 2016
    Applicant: Mitsubishi Electric Corporation
    Inventors: Nobuhide MORI, Keiichi ENOKI
  • Publication number: 20160226431
    Abstract: This invention provides a protective device for a vehicle inverter, with which an inverter element can be protected from overheating while preventing a reduction in drivability. The protective device for a vehicle inverter includes a maximum element temperature calculation unit that calculates a maximum element temperature among respective element temperatures of the inverter, and an element temperature output limit coefficient calculation unit that calculates an output limit value corresponding to the maximum element temperature, sets a current output limit value as a current output limit coefficient when the current output limit value is smaller than a preceding output limit coefficient, and sets, as the current output limit coefficient, a value obtained by adding a predetermined value determined in advance to the preceding output limit coefficient when the current output limit value equals or exceeds the preceding output limit coefficient.
    Type: Application
    Filed: November 7, 2013
    Publication date: August 4, 2016
    Applicant: Mitsubishi Electric Corporation
    Inventor: Keiichi ENOKI
  • Publication number: 20160167662
    Abstract: In order to provide a traction control device capable of preventing an initial slip at a start, the traction control device includes a drive power source outputting drive power to a drive wheel of a vehicle; a vehicle speed sensor detecting the wheel speed of a non-drive wheel of the vehicle; and target restricted speed generating means for generating a target restricted speed for the vehicle by determining the state of a road surface from target drive torque of the vehicle, the wheel speed of the non-drive wheel, and a signal indicating the extent of operation of an accelerator by a driver. The target restricted speed generated by the target restricted. speed generating means is switched stepwise in a speed region where the speed of the drive wheel s not detected in correspondence with a control mode that is classified according to the slipperiness of a road surface.
    Type: Application
    Filed: October 31, 2013
    Publication date: June 16, 2016
    Applicant: Mitsubishi Electric Corporation
    Inventors: Hiroyuki KOBAYASHI, Masahiro IEZAWA, Keiichi ENOKI, Nobuhide MORI, Yasufumi OGAWA, Kotaro NAKANO