Patents by Inventor Toshimitsu Aizawa

Toshimitsu Aizawa 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: 20240048079
    Abstract: An electric motor drive apparatus includes an electric motor. A power conversion device, a controller, and a current detector. The controller calculates a phase of an armature flux linkage of the electric motor by using a flowing current detected by the current detector. The calculating a phase of an armature flux linkage of the electric motor includes calculating an armature flux linkage of the electric motor including an initial value of an armature flux linkage of the electric motor which is calculated from a rotational position of the electric motor estimated by using a motor flux of the electric motor measured in advance and the flowing current.
    Type: Application
    Filed: August 2, 2023
    Publication date: February 8, 2024
    Applicants: KABUSHIKI KAISHA TOSHIBA, Toshiba Electronic Devices & Storage Corporation
    Inventors: Takashi TAKAGI, Toshimitsu AIZAWA, Tadashi ASUKAI
  • Publication number: 20230251327
    Abstract: In an embodiment, a diagnostic apparatus of an electric power converter is provided, and the electric power converter outputs a converted AC electric power to an electric motor, thereby driving the electric motor. The diagnostic apparatus includes an output control unit and a degradation determination unit. The output control unit controls operations of semiconductor elements of the electric power converter, thereby outputting electric power from the electric power converter to the electric motor by constant voltage output, which constantly sets an output voltage to the electric motor in a target voltage pattern. The degradation determination unit determines a degradation state for at least one of the semiconductor elements based on a current flowing through the electric motor in the constant voltage output.
    Type: Application
    Filed: December 9, 2022
    Publication date: August 10, 2023
    Inventors: Toshimitsu Aizawa, Shinichi Kominato, Tsuyoshi Shinohara, Kohei Hasegawa
  • Patent number: 11658596
    Abstract: A motor control device of an embodiment includes a power supply unit that supplies AC power to a motor; a current detection unit that detects a current flowing through a winding of the motor; a speed and electric angle estimation unit that estimates a rotation speed and an electric angle of the motor based on a voltage outputted by the power supply unit and the current; a coordinate conversion unit that obtains an excitation current and a torque current based on the current and the electric angle; a torque current command determination unit that substitutes a predicted torque calculated based on a mechanical motion equation into a torque component current command value calculated based on a torque expression of a vector control coordinate, to generate a torque component current command value for bringing a difference between an inputted speed command and an estimated speed closer to zero; and a model prediction control unit that applies, to a plurality of predicted currents including a current change ratio de
    Type: Grant
    Filed: May 18, 2022
    Date of Patent: May 23, 2023
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA CARRIER CORPORATION
    Inventors: Takeshi Shibayama, Mariko Kuboi, Toshimitsu Aizawa, Naohito Kamiya, Yoshitaka Uchiyama
  • Publication number: 20230045429
    Abstract: A motor control device of an embodiment includes a power supply unit that supplies AC power to a motor; a current detection unit that detects a current flowing through a winding of the motor; a speed and electric angle estimation unit that estimates a rotation speed and an electric angle of the motor based on a voltage outputted by the power supply unit and the current; a coordinate conversion unit that obtains an excitation current and a torque current based on the current and the electric angle; a torque current command determination unit that substitutes a predicted torque calculated based on a mechanical motion equation into a torque component current command value calculated based on a torque expression of a vector control coordinate, to generate a torque component current command value for bringing a difference between an inputted speed command and an estimated speed closer to zero; and a model prediction control unit that applies, to a plurality of predicted currents including a current change ratio de
    Type: Application
    Filed: May 18, 2022
    Publication date: February 9, 2023
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA CARRIER CORPORATION
    Inventors: Takeshi SHIBAYAMA, Mariko KUBOI, Toshimitsu AIZAWA, Naohito KAMIYA, Yoshitaka UCHIYAMA
  • Patent number: 11456689
    Abstract: According to one embodiment, a driving device includes a voltage controller, a parameter setter, and a phase adjuster. The voltage controller causes an electric power converter to apply a drive voltage to the electric motor, the electric power converter converting input electric power to A/C electric power having desired voltage and frequency and supplying the converted electric power to an electric motor. The parameter setter sets at least one of a rotation speed of the electric motor and a parameter related to the rotation speed as speed information. The phase adjuster adjusts a phase of the drive voltage in such a manner that an index calculated based on a current flowing in the electric motor and the speed information set in the parameter setter becomes smaller.
    Type: Grant
    Filed: December 23, 2019
    Date of Patent: September 27, 2022
    Assignees: KABUSHIKI KAISHA TOSHIBA, Toshiba Electronic Devices & Storage Corporation
    Inventors: Takashi Takagi, Toshimitsu Aizawa, Shen Wang
  • Patent number: 11271513
    Abstract: A driving device of one embodiment includes a phase estimator and a voltage controller. The phase estimator estimates a phase of stator interlinkage magnetic flux of an electric motor based on a current flowing through the electric motor, a voltage command of a drive voltage applied to the electric motor, and a winding resistance value of the electric motor. The voltage controller acquires a first voltage vector component in a direction in which the stator interlinkage magnetic flux acts and a second voltage vector component in a direction which is orthogonal to the direction in which the stator interlinkage magnetic flux acts for the voltage command of the drive voltage, and sets the voltage command of the drive voltage based on the first voltage vector component and the second voltage vector component.
    Type: Grant
    Filed: March 1, 2021
    Date of Patent: March 8, 2022
    Assignees: KABUSHIKI KAISHA TOSHIBA, Toshiba Electronic Devices & Storage Corporation
    Inventors: Takashi Takagi, Toshimitsu Aizawa, Shen Wang
  • Publication number: 20210281205
    Abstract: A driving device of one embodiment includes a phase estimator and a voltage controller. The phase estimator estimates a phase of stator interlinkage magnetic flux of an electric motor based on a current flowing through the electric motor, a voltage command of a drive voltage applied to the electric motor, and a winding resistance value of the electric motor. The voltage controller acquires a first voltage vector component in a direction in which the stator interlinkage magnetic flux acts and a second voltage vector component in a direction which is orthogonal to the direction in which the stator interlinkage magnetic flux acts for the voltage command of the drive voltage, and sets the voltage command of the drive voltage based on the first voltage vector component and the second voltage vector component.
    Type: Application
    Filed: March 1, 2021
    Publication date: September 9, 2021
    Applicants: KABUSHIKI KAISHA TOSHIBA, Toshiba Electronic Devices & Storage Corporation
    Inventors: Takashi TAKAGI, Toshimitsu AIZAWA, Shen WANG
  • Publication number: 20200295687
    Abstract: According to one embodiment, a driving device includes a voltage controller, a parameter setter, and a phase adjuster. The voltage controller causes an electric power converter to apply a drive voltage to the electric motor, the electric power converter converting input electric power to A/C electric power having desired voltage and frequency and supplying the converted electric power to an electric motor. The parameter setter sets at least one of a rotation speed of the electric motor and a parameter related to the rotation speed as speed information. The phase adjuster adjusts a phase of the drive voltage in such a manner that an index calculated based on a current flowing in the electric motor and the speed information set in the parameter setter becomes smaller.
    Type: Application
    Filed: December 23, 2019
    Publication date: September 17, 2020
    Applicants: KABUSHIKI KAISHA TOSHIBA, Toshiba Electronic Devices & Storage Corporation
    Inventors: Takashi TAKAGI, Toshimitsu AIZAWA, Shen WANG
  • Patent number: 10630213
    Abstract: A motor control integrated circuit according to embodiments outputs predetermined PWM signals to an inverter circuit that drives a synchronous motor and is configured to perform on-off control on a plurality of three-phase bridge connected switching elements in accordance with the PWM signals to convert direct current into three-phase alternating current, and includes: a PWM generation unit configured to generate the signals based on a received speed command value and output the PWM signals; and a current detection unit configured to detect differential values of phase currents at a predetermined time point that is fixed within a period of a carrier wave used for PWM control, based on the carrier wave and a signal generated by a current detector for detecting current conducted to the synchronous motor, wherein the PWM generation unit calculates a speed of the synchronous motor based on the differential values and then, based on the speed, generates the PWM signals to be applied to the synchronous motor.
    Type: Grant
    Filed: September 18, 2018
    Date of Patent: April 21, 2020
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Sari Maekawa, Shinichi Kominato, Toshimitsu Aizawa, Naoki Oomura, Junichiro Hagura, Sadao Ikeda
  • Patent number: 10630221
    Abstract: A motor control device including a PWM generator generating a PWM generator generating a PWM signal to be outputted to a drive circuit that energizes a winding of a switched reluctance motor; a rectangular wave generator outputting a rectangular wave signal of 1 pulse or more to the drive circuit in 1 drive period of each phase based on a rotational position of the motor; and a drive signal switcher executing switching so that a PWM drive by the PWM signal is performed when a rotational speed of the motor is equal to or less than a threshold value and a rectangular wave drive by the rectangular wave signal is performed when the rotational speed of the motor is greater than the threshold value. The PWM generator synchronizes a timing to start generation of a carrier of the PWM signal with rising of the rectangular wave signal.
    Type: Grant
    Filed: July 25, 2017
    Date of Patent: April 21, 2020
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Toshimitsu Aizawa, Makoto Shinohara, Shigeru Nakajima
  • Publication number: 20190312534
    Abstract: According to an embodiment of the present invention, a control circuit of a motor drive device activates a first timer according to the rotational position of a motor, controls, on the basis of the time counted by the first timer, the on-timing of positive-side switching elements that constitute an inverter circuit, and energizes the motor. The control circuit also activates a second timer according to the on-timing, controls the off-timing of the positive-side switching elements, on the basis of the time counted by the second timer, sets negative-side switching elements of two opposing arms to be in an on-state to cause a reflux current to flow, and then changes an energization direction to the motor. When the rotational position is set to a position for activating the first timer before the on-timing, turning on of the positive-side switching elements and activation of the second timer, which are scheduled to be performed at the on-timing, are carried out.
    Type: Application
    Filed: June 24, 2019
    Publication date: October 10, 2019
    Applicant: Toshiba Lifestyle Products & Services Corporation
    Inventor: Toshimitsu AIZAWA
  • Publication number: 20190089274
    Abstract: A motor control integrated circuit according to embodiments outputs predetermined PWM signals to an inverter circuit that drives a synchronous motor and is configured to perform on-off control on a plurality of three-phase bridge connected switching elements in accordance with the PWM signals to convert direct current into three-phase alternating current, and includes: a PWM generation unit configured to generate the signals based on a received speed command value and output the PWM signals; and a current detection unit configured to detect differential values of phase currents at a predetermined time point that is fixed within a period of a carrier wave used for PWM control, based on the carrier wave and a signal generated by a current detector for detecting current conducted to the synchronous motor, wherein the PWM generation unit calculates a speed of the synchronous motor based on the differential values and then, based on the speed, generates the PWM signals to be applied to the synchronous motor.
    Type: Application
    Filed: September 18, 2018
    Publication date: March 21, 2019
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Sari MAEKAWA, Shinichi Kominato, Toshimitsu Aizawa, Naoki Oomura, Junichiro Hagura, Sadao Ikeda
  • Publication number: 20180331639
    Abstract: A motor drive device of an embodiment includes: a power conversion circuit configured by connecting, in parallel, a plurality of legs respectively including series circuits of respective positive-side and negative-side switching elements, the power conversion circuit driving a motor; a control circuit generating and outputting an on/off signal to each of the switching elements constituting the power conversion circuit to control the motor; a rotational position detector detecting a rotational position of the motor; a rectifier full-wave rectifying input AC power supply voltage and outputting an obtained full-wave rectified voltage; and a voltage detector detecting the full-wave rectified voltage.
    Type: Application
    Filed: May 14, 2018
    Publication date: November 15, 2018
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Toshimitsu Aizawa
  • Publication number: 20180034400
    Abstract: A motor control device including a PWM generator generating a PWM generator generating a PWM signal to be outputted to a drive circuit that energizes a winding of a switched reluctance motor; a rectangular wave generator outputting a rectangular wave signal of 1 pulse or more to the drive circuit in 1 drive period of each phase based on a rotational position of the motor; and a drive signal switcher executing switching so that a PWM drive by the PWM signal is performed when a rotational speed of the motor is equal to or less than a threshold value and a rectangular wave drive by the rectangular wave signal is performed when the rotational speed of the motor is greater than the threshold value. The PWM generator synchronizes a timing to start generation of a carrier of the PWM signal with rising of the rectangular wave signal.
    Type: Application
    Filed: July 25, 2017
    Publication date: February 1, 2018
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Toshimitsu AIZAWA, Makoto Shinohara, Shigeru Nakajima
  • Patent number: 9225271
    Abstract: A motor driving apparatus according to an embodiment includes a brushless motor. The motor driving apparatus includes a position sensor that outputs a position detection signal in synchronization with a phase of an induced voltage of a coil of the brushless motor. The motor driving apparatus includes a semiconductor integrated circuit that controls driving of the brushless motor by supplying a pseudo sine-wave driving voltage from an energization terminal to the coil of the brushless motor based on the position detection signal and a command signal that prescribes driving of the brushless motor.
    Type: Grant
    Filed: August 21, 2014
    Date of Patent: December 29, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Naoki Oomura, Kazunobu Nagai, Toshimitsu Aizawa, Sadao Ikeda, Jun Sodesawa, Hiroyuki Ishida
  • Publication number: 20150054437
    Abstract: A motor driving apparatus according to an embodiment includes a brushless motor. The motor driving apparatus includes a position sensor that outputs a position detection signal in synchronization with a phase of an induced voltage of a coil of the brushless motor. The motor driving apparatus includes a semiconductor integrated circuit that controls driving of the brushless motor by supplying a pseudo sine-wave driving voltage from an energization terminal to the coil of the brushless motor based on the position detection signal and a command signal that prescribes driving of the brushless motor.
    Type: Application
    Filed: August 21, 2014
    Publication date: February 26, 2015
    Inventors: Naoki Oomura, Kazunobu Nagai, Toshimitsu Aizawa, Sadao Ikeda, Jun Sodesawa, Hiroyuki Ishida
  • Patent number: 8441219
    Abstract: A motor control device controlling an inverter to control an electric motor, includes a plurality of function sections, a voltage command generating section generating a d-axis voltage command and a q-axis voltage command, a voltage operational processing section, an input current operation section, a speed information generating section estimating a rotational speed of the motor based on at least one of a motor constant, a positional information generating section delivering positional information about a rotor, and a processor executing control software set by a user or a manufacturer. At least a part of the function sections are configured by hardware. The function section configured by the hardware is given at least one parameter retaining section. The parameter retaining section is configured so as to be readable/writable on the processor. The function section is configured by the hardware so as to be operated in a predetermined sequence.
    Type: Grant
    Filed: September 15, 2010
    Date of Patent: May 14, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shuting Li, Nobuyuki Suzuki, Toshikazu Sekihara, Kazunobu Nagai, Yukihisa Hasegawa, Toshimitsu Aizawa, Sari Maekawa
  • Publication number: 20110062903
    Abstract: A motor control device controlling an inverter to control an electric motor, includes a plurality of function sections, a voltage command generating section generating a d-axis voltage command and a q-axis voltage command, a voltage operational processing section, an input current operation section, a speed information generating section estimating a rotational speed of the motor based on at least one of a motor constant, a positional information generating section delivering positional information about a rotor, a processor executing control software set by a user, a manufacturer or the like. At least a part of the function sections are configured by hardware. The function section configured by the hardware is given at least one parameter retaining section. The parameter retaining section is configured so as to be readable/writable on the processor. The function section is configured by the hardware so as to be operated in a predetermined sequence.
    Type: Application
    Filed: September 15, 2010
    Publication date: March 17, 2011
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Shuting LI, Nobuyuki Suzuki, Toshikazu Sekihara, Kazunobu Nagai, Yukihisa Hasegawa, Toshimitsu Aizawa, Sari Maekawa
  • Patent number: 7638967
    Abstract: A motor control unit includes a power converter unit that energize a motor based on a commutating signal, the motor having a rotor provided with a permanent magnet and a stator having a coil wound thereto; a start-up controller that outputs a commutating signal to the power converter unit during a start-up operation, the commutating signal having a predetermined conductive pattern corresponding to a command rotational speed; a voltage calculator that calculates a voltage of the motor during the start-up operation by applying a parameter for the motor, the command rotational speed, and a current flown in the coil of the motor to a voltage-current equation of the motor; and a determiner that, during the start-up operation, compares a voltage calculated by the voltage calculator and an actual voltage of the motor and that determines occurrence of rotational abnormalities when the actual voltage is lower than the calculated voltage.
    Type: Grant
    Filed: June 28, 2007
    Date of Patent: December 29, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Toshimitsu Aizawa, Tsuyoshi Hosoito
  • Publication number: 20080042613
    Abstract: A motor control unit includes a power converter unit that energize a motor based on a commutating signal, the motor having a rotor provided with a permanent magnet and a stator having a coil wound thereto; a start-up controller that outputs a commutating signal to the power converter unit during a start-up operation, the commutating signal having a predetermined conductive pattern corresponding to a command rotational speed; a voltage calculator that calculates a voltage of the motor during the start-up operation by applying a parameter for the motor, the command rotational speed, and a current flown in the coil of the motor to a voltage-current equation of the motor; and a determiner that, during the start-up operation, compares a voltage calculated by the voltage calculator and an actual voltage of the motor and that determines occurrence of rotational abnormalities when the actual voltage is lower than the calculated voltage.
    Type: Application
    Filed: June 28, 2007
    Publication date: February 21, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Toshimitsu Aizawa, Tsuyoshi Hosoito