Patents by Inventor Tokuji TATEWAKI

Tokuji TATEWAKI 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: 11958543
    Abstract: A motor control system includes an inverter, and a control calculation unit that feedback-controls the inverter. The control calculation unit includes a voltage control calculation unit that calculates a voltage command value indicating a voltage to be applied to the motor from the inverter on the basis of a current deviation between a current command value and an actual current detection value, a torque ripple compensation calculation unit that adds a compensation value for compensating a torque ripple in the motor to a signal value on at least one of an upstream side and a downstream side in a signal flow that passes through the voltage control calculation unit, and a current limit calculation unit that limits the current command value by adaptive control based on an actual angular velocity value indicating an angular velocity at which the motor rotates.
    Type: Grant
    Filed: February 13, 2019
    Date of Patent: April 16, 2024
    Assignee: NIDEC CORPORATION
    Inventors: Shuji Endo, Tokuji Tatewaki, Tomoya Ueda, Masanori Watahiki, Tomonari Mori
  • Patent number: 11952057
    Abstract: A motor control system includes an inverter, a voltage control calculating a voltage command value indicating a voltage to be applied to a motor from the inverter based on a deviation between the current command value and the actual current detection value, and a torque ripple compensation unit adding a compensation value for compensating a torque ripple in the motor to a signal value on an upstream side in a signal flow that passes through the voltage control unit. The torque ripple compensation unit includes a phase compensator calculating a compensation value component in the voltage control unit based on an actual angular velocity value indicating an angular velocity at which the motor rotates, and an inverse characteristic processor calculating a compensation value component for compensating the torque ripple based on an inverse characteristic of an open loop transfer function in a feedback control.
    Type: Grant
    Filed: February 13, 2019
    Date of Patent: April 9, 2024
    Assignee: NIDEC CORPORATION
    Inventors: Shuji Endo, Tokuji Tatewaki, Tomoya Ueda, Masanori Watahiki, Tomonari Mori
  • Patent number: 11362608
    Abstract: One aspect of a noise compensation adjustment method includes: a measurement step of driving a motor to measure noise with respect to a coupled system including the motor and a driving body coupled to the motor and driven by the motor; an order identification step of, based on noise measured in the measurement step, identifying an order B of a component contributing to compensation of the noise from a k-th component and a 1/k-th component (k is an integer) in the rotation of the motor; an adjustment step of controlling driving of the motor using a component of the order B identified in the order identification step as a compensation value, and adjusting a component value of the order B to reduce the noise; and a recording step of recording the component value of the order B adjusted in the adjustment step as a compensation value for reducing the noise.
    Type: Grant
    Filed: February 8, 2019
    Date of Patent: June 14, 2022
    Assignee: NIDEC CORPORATION
    Inventors: Shuji Endo, Akitoshi Harada, Tomoya Ueda, Masanori Watahiki, Tomonari Mori, Tokuji Tatewaki
  • Patent number: 11296637
    Abstract: A control device includes angular velocity detecting circuitry, feedback circuitry, torque command calculation circuitry, a limiter, a drive controller, and correction circuitry. The angular velocity detecting circuitry detects an angular velocity of a motor. The feedback circuitry obtains a feedback value from the angular velocity. The torque command calculation circuitry obtains a torque command value according to a superordinate torque command value supplied from a superordinate device and the feedback value. The limiter limits the torque command value obtained by the torque command calculation circuitry so as not to exceed a preset torque upper limit value. The drive controller performs a drive control of the motor according to the limited torque command value. The correction circuitry corrects the superordinate torque command value or the torque command value according to the feedback value and the superordinate torque command value.
    Type: Grant
    Filed: January 3, 2020
    Date of Patent: April 5, 2022
    Assignees: NIDEC CORPORATION, NIDEC ELESYS CORPORATION
    Inventors: Linfeng Lan, Tomonari Mori, Ryo Itaba, Tokuji Tatewaki
  • Patent number: 11271503
    Abstract: A technique for reducing an operation noise even when a high-pass filter is used for controlling a motor is provided. A controller is used in a motor control system for driving a motor used for position control by using a drive circuit and an inverter. The controller includes a current control block for receiving a motor current and outputting a reference voltage, a motor control circuit for outputting a signal indicating a duty ratio from the reference voltage output from the current control block, a dead band compensation block for calculating a compensation value of a non-linear element of a drive system, and an adder. The dead band compensation block outputs a duty value corresponding to the dead band at a timing at which the motor current crosses zero. The adder adds the duty value to a signal indicating the duty ratio and outputs the signal.
    Type: Grant
    Filed: November 22, 2018
    Date of Patent: March 8, 2022
    Assignee: NIDEC CORPORATION
    Inventors: Shuji Endo, Hajime Nakane, Takuya Yokozuka, Mikio Morishima, Tokuji Tatewaki
  • Patent number: 11251731
    Abstract: A motor control system includes an inverter, and a control unit that feedback-controls the inverter. The control unit includes a voltage control unit that calculates a voltage command value indicating a voltage to be applied to the motor from the inverter based on a current deviation between a current command value and an actual current detection value, and a torque ripple compensation unit that adds a compensation value for compensating a torque ripple in the motor to a signal value on at least one of an upstream side and a downstream side in a signal flow passing through the voltage control unit. The torque ripple compensation unit calculates the compensation value based on an actual angular velocity at which the motor rotates and the target current command value, and based on advance angle control for compensating a response delay of the motor control system with respect to the compensation value.
    Type: Grant
    Filed: February 8, 2019
    Date of Patent: February 15, 2022
    Assignee: NIDEC CORPORATION
    Inventors: Shuji Endo, Tokuji Tatewaki, Tomoya Ueda, Masanori Watahiki, Tomonari Mori
  • Patent number: 11139766
    Abstract: A technique for reducing an operation noise even when a high-pass filter is used for controlling a motor is provided. A controller is used in a motor control system for driving a motor by using a drive circuit and an inverter. The controller includes a current control block. The controller performs feedforward control by using a current value, compensates for a term of a self-inductance of the motor included in a current control block by an inverse model, compensates for a phase characteristic of a transfer function of the inverse model by an advance component, and corrects a gain characteristic of the transfer function of the inverse model by a function of a physical quantity obtained based on an angular velocity of the motor, thereby compensating for a phase delay and a gain reduction of a torque output generated by the self-inductance.
    Type: Grant
    Filed: November 22, 2018
    Date of Patent: October 5, 2021
    Assignees: NIDEC CORPORATION, NIDEC ELESYS CORPORATION
    Inventors: Shuji Endo, Hajime Nakane, Takuya Yokozuka, Mikio Morishima, Tokuji Tatewaki
  • Publication number: 20210044234
    Abstract: A motor control system includes an inverter, and a control unit that feedback-controls the inverter. The control unit includes a voltage control unit that calculates a voltage command value indicating a voltage to be applied to the motor from the inverter based on a current deviation between a current command value and an actual current detection value, and a torque ripple compensation unit that adds a compensation value for compensating a torque ripple in the motor to a signal value on at least one of an upstream side and a downstream side in a signal flow passing through the voltage control unit. The torque ripple compensation unit calculates the compensation value based on an actual angular velocity at which the motor rotates and the target current command value, and based on advance angle control for compensating a response delay of the motor control system with respect to the compensation value.
    Type: Application
    Filed: February 8, 2019
    Publication date: February 11, 2021
    Inventors: Shuji ENDO, Tokuji TATEWAKI, Tomoya UEDA, Masanori WATAHIKI, Tomonari MORI
  • Publication number: 20210006189
    Abstract: A technique for reducing an operation noise even when a high-pass filter is used for controlling a motor is provided. A controller is used in a motor control system for driving a motor by using a drive circuit and an inverter. The controller includes a current control block. The controller performs feedforward control by using a current value, compensates for a term of a self-inductance of the motor included in a current control block by an inverse model, compensates for a phase characteristic of a transfer function of the inverse model by an advance component, and corrects a gain characteristic of the transfer function of the inverse model by a function of a physical quantity obtained based on an angular velocity of the motor, thereby compensating for a phase delay and a gain reduction of a torque output generated by the self-inductance.
    Type: Application
    Filed: November 22, 2018
    Publication date: January 7, 2021
    Inventors: Shuji ENDO, Hajime NAKANE, Takuya YOKOZUKA, Mikio MORISHIMA, Tokuji TATEWAKI
  • Publication number: 20210006188
    Abstract: A technique for reducing an operation noise even when a high-pass filter is used for controlling a motor is provided. A controller is used in a motor control system for driving a motor used for position control by using a drive circuit and an inverter. The controller includes a current control block for receiving a motor current and outputting a reference voltage, a motor control circuit for outputting a signal indicating a duty ratio from the reference voltage output from the current control block, a dead band compensation block for calculating a compensation value of a non-linear element of a drive system, and an adder. The dead band compensation block outputs a duty value corresponding to the dead band at a timing at which the motor current crosses zero. The adder adds the duty value to a signal indicating the duty ratio and outputs the signal.
    Type: Application
    Filed: November 22, 2018
    Publication date: January 7, 2021
    Inventors: Shuji ENDO, Hajime NAKANE, Takuya YOKOZUKA, Mikio MORISHIMA, Tokuji TATEWAKI
  • Publication number: 20200406957
    Abstract: A motor control system includes an inverter, a voltage control calculating a voltage command value indicating a voltage to be applied to a motor from the inverter based on a deviation between the current command value and the actual current detection value, and a torque ripple compensation unit adding a compensation value for compensating a torque ripple in the motor to a signal value on an upstream side in a signal flow that passes through the voltage control unit. The torque ripple compensation unit includes a phase compensator calculating a compensation value component in the voltage control unit based on an actual angular velocity value indicating an angular velocity at which the motor rotates, and an inverse characteristic processor calculating a compensation value component for compensating the torque ripple based on an inverse characteristic of an open loop transfer function in a feedback control.
    Type: Application
    Filed: February 13, 2019
    Publication date: December 31, 2020
    Inventors: Shuji ENDO, Tokuji TATEWAKI, Tomoya UEDA, Masanori WATAHIKI, Tomonari MORI
  • Publication number: 20200406958
    Abstract: A motor control system includes an inverter and a control calculation unit. The control calculation unit includes a voltage control calculation unit that calculates a voltage command value indicating a voltage to be applied to a motor from the inverter on the basis of a current deviation between the current command value and the actual current detection value, and a compensation calculation unit that compensates at least one of a k-th component and a 1/k-th component in the motor with respect to a signal value on at least one of an upstream side and a downstream side in a signal flow that passes through the voltage control calculation unit. The compensation calculation unit calculates a compensation value on the basis of an actual angular velocity value indicating an angular velocity at which the motor rotates and the target current command value, while also taking into account advance angle control.
    Type: Application
    Filed: February 8, 2019
    Publication date: December 31, 2020
    Inventors: Shuji ENDO, Akitoshi HARADA, Tomoya UEDA, Masanori WATAHIKI, Tomonari MORI, Tokuji TATEWAKI
  • Publication number: 20200395877
    Abstract: One aspect of a noise compensation adjustment method includes: a measurement step of driving a motor to measure noise with respect to a coupled system including the motor and a driving body coupled to the motor and driven by the motor; an order identification step of, based on noise measured in the measurement step, identifying an order B of a component contributing to compensation of the noise from a k-th component and a 1/k-th component (k is an integer) in the rotation of the motor; an adjustment step of controlling driving of the motor using a component of the order B identified in the order identification step as a compensation value, and adjusting a component value of the order B to reduce the noise; and a recording step of recording the component value of the order B adjusted in the adjustment step as a compensation value for reducing the noise.
    Type: Application
    Filed: February 8, 2019
    Publication date: December 17, 2020
    Inventors: Shuji ENDO, Akitoshi HARADA, Tomoya UEDA, Masanori WATAHIKI, Tomonari MORI, Tokuji TATEWAKI
  • Patent number: 10862415
    Abstract: A motor controller includes an inverter that drives a motor, an operation controller that controls the inverter according to a current command value, and a torque ripple compensation generator that adds a compensation value to compensate for a torque ripple in the motor to the current command value. The operation controller uses, as the current command value, a q-axis current command value indicating a q-axis current in a rotational coordinate system of the motor, and also uses, as the current command value, at least temporarily a d-axis current command value indicating a d-axis current in the rotational coordinate system, and the torque ripple compensation generator calculates a phase difference of the compensation value with respect to the q-axis current command value according to an equation using the q-axis current command value and the d-axis current command value as variables.
    Type: Grant
    Filed: August 8, 2019
    Date of Patent: December 8, 2020
    Assignees: NIDEC CORPORATION, NIDEC ELESYS CORPORATION
    Inventors: Masanori Watahiki, Tomonari Mori, Tomoya Ueda, Shuji Endo, Tokuji Tatewaki
  • Publication number: 20200377144
    Abstract: A motor control system includes an inverter, and a control calculation unit that feedback-controls the inverter. The control calculation unit includes a voltage control calculation unit that calculates a voltage command value indicating a voltage to be applied to the motor from the inverter on the basis of a current deviation between a current command value and an actual current detection value, a torque ripple compensation calculation unit that adds a compensation value for compensating a torque ripple in the motor to a signal value on at least one of an upstream side and a downstream side in a signal flow that passes through the voltage control calculation unit, and a current limit calculation unit that limits the current command value by adaptive control based on an actual angular velocity value indicating an angular velocity at which the motor rotates.
    Type: Application
    Filed: February 13, 2019
    Publication date: December 3, 2020
    Inventors: Shuji ENDO, Tokuji TATEWAKI, Tomoya UEDA, Masanori WATAHIKI, Tomonari MORI
  • Publication number: 20200313594
    Abstract: A control device includes angular velocity detecting circuitry, feedback circuitry, torque command calculation circuitry, a limiter, a drive controller, and correction circuitry. The angular velocity detecting circuitry detects an angular velocity of a motor. The feedback circuitry obtains a feedback value from the angular velocity. The torque command calculation circuitry obtains a torque command value according to a superordinate torque command value supplied from a superordinate device and the feedback value. The limiter limits the torque command value obtained by the torque command calculation circuitry so as not to exceed a preset torque upper limit value. The drive controller performs a drive control of the motor according to the limited torque command value. The correction circuitry corrects the superordinate torque command value or the torque command value according to the feedback value and the superordinate torque command value.
    Type: Application
    Filed: January 3, 2020
    Publication date: October 1, 2020
    Inventors: Linfeng LAN, Tomonari MORI, Ryo ITABA, Tokuji TATEWAKI
  • Publication number: 20200091854
    Abstract: An inverter control method for preventing an increase or decrease fluctuation of a duty ratio of a pulse width modulation signal due to the dead time and suppressing generation of a torque ripple. A duty converter performs duty conversion on an input voltage waveform to a motor terminal voltage input circuitry to which a motor terminal voltage corresponding to each phase of an electric motor is input, and sets it as a detected duty. A command duty correction circuitry adds, to the command duty generated by a command duty generator, a differential duty that is a difference between the command duty and the detected duty, or subtracts the differential duty from the command duty, according to the direction of the phase current. Thereby, duty correction is performed to match the switching characteristics of the phase current before correction with the ideal characteristics.
    Type: Application
    Filed: August 27, 2019
    Publication date: March 19, 2020
    Inventor: Tokuji TATEWAKI
  • Publication number: 20200059182
    Abstract: A motor controller includes an inverter that drives a motor, an operation controller that controls the inverter according to a current command value, and a torque ripple compensation generator that adds a compensation value to compensate for a torque ripple in the motor to the current command value. The operation controller uses, as the current command value, a q-axis current command value indicating a q-axis current in a rotational coordinate system of the motor, and also uses, as the current command value, at least temporarily a d-axis current command value indicating a d-axis current in the rotational coordinate system, and the torque ripple compensation generator calculates a phase difference of the compensation value with respect to the q-axis current command value according to an equation using the q-axis current command value and the d-axis current command value as variables.
    Type: Application
    Filed: August 8, 2019
    Publication date: February 20, 2020
    Inventors: Masanori WATAHIKI, Tomonari MORI, Tomoya UEDA, Shuji ENDO, Tokuji TATEWAKI
  • Patent number: 9540036
    Abstract: An electronic control apparatus configured to control electric power steering and provided integrally with an electric motor is electrically connected to an ignition switch and which assists a rotation operation of a steering column by rotation of the electric motor. A first magnetism detecting element configured to operate using power supplied via the ignition switch to output a first set of rotation angle signals of the electric motor. A second magnetism detecting element configured to operate continuously using continuously supplied power to output a second set of rotation angle signals of the electric motor. A controller configured or programmed to generate rotation angle information about the electric motor based on the first set of rotation angle signals and the second set of rotation angle signals outputted while the ignition switch is stopped and to calculate a position of a steering wheel from the generated rotation angle information.
    Type: Grant
    Filed: December 19, 2014
    Date of Patent: January 10, 2017
    Assignee: Nidec Elesys Corporation
    Inventors: Kazuki Harada, Tokuji Tatewaki, Eiji Wada, Osamu Maeshima, Masatoshi Matsuzaki
  • Publication number: 20150175191
    Abstract: An electronic control apparatus configured to control electric power steering and provided integrally with an electric motor is electrically connected to an ignition switch and which assists a rotation operation of a steering column by rotation of the electric motor. A first magnetism detecting element configured to operate using power supplied via the ignition switch to output a first set of rotation angle signals of the electric motor. A second magnetism detecting element configured to operate continuously using continuously supplied power to output a second set of rotation angle signals of the electric motor. A controller configured or programmed to generate rotation angle information about the electric motor based on the first set of rotation angle signals and the second set of rotation angle signals outputted while the ignition switch is stopped and to calculate a position of a steering wheel from the generated rotation angle information.
    Type: Application
    Filed: December 19, 2014
    Publication date: June 25, 2015
    Inventors: Kazuki HARADA, Tokuji TATEWAKI, Eiji WADA, Osamu MAESHIMA, Masatoshi MATSUZAKI