Patents by Inventor Takayoshi Sugawara

Takayoshi Sugawara 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: 20200172163
    Abstract: [Problem] An electric power steering apparatus includes: a current command value determining section that determines a current command value based on steering torque and vehicle speed; a vibration extracting filter that extracts a first vibration component having a predetermined amplitude and first predetermined frequency range depending on motor angular velocity; a vibration extracting section that extracts a second vibration component having a second predetermined frequency range depending on motor angular acceleration; a first compensation value calculating section that calculates a first vibration suppression compensation value based on the first vibration component extracted by the vibration extracting filter; and a second compensation value calculating section that calculates a second vibration suppression compensation value based on the second vibration component; and suppresses vibrations of the motor by feeding back the first vibration suppression compensation value and the second vibration suppressi
    Type: Application
    Filed: February 10, 2020
    Publication date: June 4, 2020
    Applicant: NSK LTD.
    Inventors: Takayoshi SUGAWARA, Yousuke IMAMURA, Masahiro MAEDA
  • Patent number: 10668941
    Abstract: An electric power steering apparatus compensates a dead time of an inverter without tuning operation, improves distortion of a current waveform and responsibility of a current control, and suppresses sound, vibration and ripple. The apparatus calculates dq-axes steering-assist command values based on at least a steering torque, calculates dq-axes current command values from the dq-axes steering-assist command values, converts the dq-axes current command values into 3-phase duty command values, driving-controls a 3-phase brushless motor by an inverter of a PWM control, and applies an assist torque to a steering system of a vehicle. Dead time reference compensation values are calculated based on a motor rotational angle. Dead time compensation of the inverter adds dead time compensation values in which the dead time reference compensation values are processed by using a gain, a sign and the like, to dq-axes voltage command values or to 3-phase voltage command values.
    Type: Grant
    Filed: July 14, 2017
    Date of Patent: June 2, 2020
    Assignee: NSK LTD.
    Inventors: Hiroaki Takase, Ryo Minaki, Hideki Sawada, Takayoshi Sugawara
  • Publication number: 20200130730
    Abstract: [Problem] An object of the present invention is to provide a vector control type motor control unit that compensates a dead time of an inverter without a tuning operation, improves a distortion of a current waveform and responsibility of the current control, and suppresses sound, vibration and a torque ripple.
    Type: Application
    Filed: June 12, 2018
    Publication date: April 30, 2020
    Applicant: NSK LTD.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA
  • Patent number: 10597071
    Abstract: An electric power steering apparatus of vector control system that calculates steering assist command values of dq axes based on at least a steering torque, calculates dq-axes current command values from the steering assist command values, converts the dq-axes current command values into 3-phase duty command values, driving-controls a 3-phase brushless motor by an inverter of a PWM control, and applies an assist torque to a steering system of a vehicle, wherein the electric power steering apparatus has plural dead time compensating functions of which efficiencies to respectively perform a dead time compensation of the inverter are different each other, and performs the dead time compensation by switching from one of the plural dead time compensating functions to an another dead time compensating function with a predetermined condition.
    Type: Grant
    Filed: August 16, 2017
    Date of Patent: March 24, 2020
    Assignee: NSK LTD.
    Inventors: Hiroaki Takase, Ryo Minaki, Hideki Sawada, Takayoshi Sugawara
  • Patent number: 10589779
    Abstract: An electric power steering apparatus includes: a current command value determining section that determines a current command value based on steering torque and vehicle speed; a vibration extracting filter that extracts a first vibration component having a predetermined amplitude and first predetermined frequency range depending on motor angular velocity; a vibration extracting section that extracts a second vibration component having a second predetermined frequency range depending on motor angular acceleration; a first compensation value calculating section that calculates a first vibration suppression compensation value based on the first vibration component extracted by the vibration extracting filter; and a second compensation value calculating section that calculates a second vibration suppression compensation value based on the second vibration component; and suppresses vibrations of the motor by feeding back the first vibration suppression compensation value and the second vibration suppression compens
    Type: Grant
    Filed: December 21, 2015
    Date of Patent: March 17, 2020
    Assignee: NSK LTD.
    Inventors: Takayoshi Sugawara, Yousuke Imamura, Masahiro Maeda
  • Patent number: 10549772
    Abstract: A vector control type electric power steering apparatus that compensates a dead time of an inverter, a motor back-EMF and an interference voltage by means of a mutual inductance between motor windings, improves a distortion of a current waveform and a responsibility of a current control, and suppresses a noisy sound, vibration and a ripple. The apparatus driving-controls a three-phase brushless motor which applies an assist torque to a steering mechanism of a vehicle by using a current command value calculated based on at least a steering torque, and vector-controls the three-phase brushless motor by using dq-axis command values that are converted from the current command value via an inverter, including: a 3-phase disturbance observer to compensate respective phase disturbance voltages, which include a dead time of the inverter, for 3-phase voltage command values.
    Type: Grant
    Filed: July 14, 2017
    Date of Patent: February 4, 2020
    Assignee: NSK LTD.
    Inventors: Ryo Minaki, Hiroaki Takase, Hideki Sawada, Takayoshi Sugawara
  • Patent number: 10530245
    Abstract: [Problem] An object of the present invention is to provide an electric power steering apparatus of a vector control system that compensates a dead time of an inverter, a motor back-EMF and an interference voltage due to a mutual inductance between motor windings, improves a distortion of a current waveform and a responsibility of a current control, and suppresses a noise, vibration and a ripple.
    Type: Grant
    Filed: July 18, 2017
    Date of Patent: January 7, 2020
    Assignee: NSK LTD.
    Inventors: Ryo Minaki, Hiroaki Takase, Hideki Sawada, Takayoshi Sugawara
  • Publication number: 20190382048
    Abstract: An electric power steering apparatus that drives and controls a motor which applies an assist orque to a steering system of a vehicle and has a function switching between an assist mode and an automatic mode, including a torsion bar torsional angle calculating section to calculate a torsion bar torsional angle based on a torque information, an output-side column shaft relative angle generating section to output an output-side relative angle from an electrical angle signal of the motor, an actual handle angle calculating section to calculate an actual handle angle based on the torsion bar torsional angle and the output-side relative angle, a resonance filter to obtain an estimated handle angle in a hands-off state from the output-side relative angle, and a hands-on/off judging section to judge a hands-on state when a time that a deviation angle between the actual handle angle and the estimated handle angle is equal to or more than a predetermined angle is continued for the predetermined time or more.
    Type: Application
    Filed: February 19, 2018
    Publication date: December 19, 2019
    Applicant: NSK LTD.
    Inventors: Hideki SAWADA, Yukie FUJIWARA, Ryo MINAKI, Takayoshi SUGAWARA
  • Publication number: 20190375449
    Abstract: An electric power steering apparatus of a vector control system that drives and controls a motor by an inverter and applies an assist torque to a steering system of a vehicle, including the first compensation function to perform a dead time (DT) compensation based on respective phase motor terminal voltages and respective phase duty command values, the second compensation function to perform a DT compensation based on steering assist command values, the third compensation function to perform the DT compensation based on dq-axis current command values, and a temperature detecting section to detect temperature of ECU, wherein the correction of the DT compensation is performed based on the temperature, wherein switches of the compensation functions are performed by using a conditional branch due to software and a gradual-changing switch, wherein the dq-axis DT compensation values after the conditional branch and the gradual-changing switch are performed are calculated, and wherein the dq-axis voltage command val
    Type: Application
    Filed: February 13, 2018
    Publication date: December 12, 2019
    Applicant: NSK LTD.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA
  • Patent number: 10494016
    Abstract: An electric power steering apparatus that ideally compensates dead time of the inverter without the tuning operation, improves distortion of the current waveform and the responsibility of the current control, and suppresses sound, vibration, the ripple that the low speed steering maneuver is effective.
    Type: Grant
    Filed: July 20, 2017
    Date of Patent: December 3, 2019
    Assignee: NSK LTD.
    Inventors: Hiroaki Takase, Ryo Minaki, Hideki Sawada, Takayoshi Sugawara
  • Patent number: 10494017
    Abstract: An electric power steering apparatus of a vector control system converts calculated dq-axes current command values into 3-phase duty command values, driving-controls a 3-phase brushless motor by an inverter of a PWM control, and applies an assist torque to a steering system of a vehicle, wherein compensation signs of 3-phase current model command values in which the dq-axes current command values are converted into a 3-phase current command value model are estimated, wherein a dead time compensation amount is calculated based on an inverter-applying voltage, and wherein dead time compensation is performed by adding dead time compensation values that are 2-phase values converted from 3-phase values in which the compensation signs are multiplied with the dead time compensation amount, to dq-axes voltage command values, or by adding 3-phase dead time compensation values to 3-phase voltage command values.
    Type: Grant
    Filed: July 7, 2017
    Date of Patent: December 3, 2019
    Assignee: NSK LTD.
    Inventors: Hiroaki Takase, Ryo Minaki, Hideki Sawada, Takayoshi Sugawara
  • Publication number: 20190344824
    Abstract: An electric power steering apparatus of vector control system that calculates steering assist command values of dq axes based on at least a steering torque, calculates dq-axes current command values from the steering assist command values, converts the dq-axes current command values into 3-phase duty command values, driving-controls a 3-phase brushless motor by an inverter of a PWM control, and applies an assist torque to a steering system of a vehicle, wherein the electric power steering apparatus has plural dead time compensating functions of which efficiencies to respectively perform a dead time compensation of the inverter are different each other, and performs the dead time compensation by switching from one of the plural dead time compensating functions to an another dead time compensating function with a predetermined condition.
    Type: Application
    Filed: August 16, 2017
    Publication date: November 14, 2019
    Applicant: NSK Ltd.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA
  • Publication number: 20190337553
    Abstract: A vector control type electric power steering apparatus that compensates a dead time of an inverter, a motor back-EMF and an interference voltage by means of a mutual inductance between motor windings, improves a distortion of a current waveform and a responsibility of a current control, and suppresses a noisy sound, vibration and a ripple. The apparatus driving-controls a three-phase brushless motor which applies an assist torque to a steering mechanism of a vehicle by using a current command value calculated based on at least a steering torque, and vector-controls the three-phase brushless motor by using dq-axis command values that are converted from the current command value via an inverter, including: a 3-phase disturbance observer to compensate respective phase disturbance voltages, which include a dead time of the inverter, for 3-phase voltage command values.
    Type: Application
    Filed: July 14, 2017
    Publication date: November 7, 2019
    Applicant: NSK LTD.
    Inventors: Ryo MINAKI, Hiroaki TAKASE, Hideki SAWADA, Takayoshi SUGAWARA
  • Publication number: 20190329817
    Abstract: An electric power steering apparatus that ideally compensates dead time of the inverter without the tuning operation, improves distortion of the current waveform and the responsibility of the current control, and suppresses sound, vibration, the ripple that the low speed steering maneuver is effective.
    Type: Application
    Filed: July 20, 2017
    Publication date: October 31, 2019
    Applicant: NSK LTD.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA
  • Publication number: 20190322309
    Abstract: An electric power steering apparatus of a vector control system that compensates a dead time of an inverter without tuning operation, improves a distortion of a current waveform and a responsibility of a current control, and suppresses a sound, a vibration and a ripple.
    Type: Application
    Filed: July 14, 2017
    Publication date: October 24, 2019
    Applicant: NSK Ltd.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA
  • Patent number: 10427710
    Abstract: An electric power steering apparatus of vector control system that calculates steering assist command values of dq axes based on at least a steering torque, calculates dq-axes current command values from the steering assist command values, converts the dq-axes current command values into 3-phase duty command values, driving-controls a 3-phase brushless motor by an inverter of a PWM control, and applies an assist torque to a steering system of a vehicle, wherein the electric power steering apparatus has plural dead time compensating functions of which efficiencies to respectively perform a dead time compensation of the inverter are different each other, and performs the dead time compensation by gradually shifting from one of the plural dead time compensating functions to an another dead time compensating function while mixing the plural dead time compensating functions.
    Type: Grant
    Filed: August 16, 2017
    Date of Patent: October 1, 2019
    Assignee: NSK LTD.
    Inventors: Hiroaki Takase, Ryo Minaki, Hideki Sawada, Takayoshi Sugawara
  • Publication number: 20190256128
    Abstract: An electric power steering apparatus of a vector control system converts calculated dq-axes current command values into 3-phase duty command values, driving-controls a 3-phase brushless motor by an inverter of a PWM control, and applies an assist torque to a steering system of a vehicle, wherein compensation signs of 3-phase current model command values in which the dq-axes current command values are converted into a 3-phase current command value model are estimated, wherein a dead time compensation amount is calculated based on an inverter-applying voltage, and wherein dead time compensation is performed by adding dead time compensation values that are 2-phase values converted from 3-phase values in which the compensation signs are multiplied with the dead time compensation amount, to dq-axes voltage command values, or by adding 3-phase dead time compensation values to 3-phase voltage command values.
    Type: Application
    Filed: July 7, 2017
    Publication date: August 22, 2019
    Applicant: NSK LTD.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA
  • Publication number: 20190252972
    Abstract: [Problem] An object of the present invention is to provide an electric power steering apparatus of a vector control system that compensates a dead time of an inverter, a motor back-EMF and an interference voltage due to a mutual inductance between motor windings, improves a distortion of a current waveform and a responsibility of a current control, and suppresses a noise, vibration and a ripple.
    Type: Application
    Filed: July 18, 2017
    Publication date: August 15, 2019
    Applicant: NSK LTD.
    Inventors: Ryo MINAKI, Hiroaki TAKASE, Hideki SAWADA, Takayoshi SUGAWARA
  • Publication number: 20190241208
    Abstract: An electric power steering apparatus of a vector control system that compensates a dead time of an inverter without tuning operation, improves a distortion of a current waveform and a responsibility of a current control, and suppresses a steering sound, a vibration and a ripple.
    Type: Application
    Filed: July 20, 2017
    Publication date: August 8, 2019
    Applicant: NSK LTD.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA
  • Publication number: 20190168801
    Abstract: An electric power steering apparatus of vector control system that calculates steering assist command values of dq axes based on at least a steering torque, calculates dq-axes current command values from the steering assist command values, converts the dq-axes current command values into 3-phase duty command values, driving-controls a 3-phase brushless motor by an inverter of a PWM control, and applies an assist torque to a steering system of a vehicle, wherein the electric power steering apparatus has plural dead time compensating functions of which efficiencies to respectively perform a dead time compensation of the inverter are different each other, and performs the dead time compensation by gradually shifting from one of the plural dead time compensating functions to an another dead time compensating function while mixing the plural dead time compensating functions.
    Type: Application
    Filed: August 16, 2017
    Publication date: June 6, 2019
    Applicant: NSK Ltd.
    Inventors: Hiroaki TAKASE, Ryo MINAKI, Hideki SAWADA, Takayoshi SUGAWARA