Patents by Inventor Toru Tazawa

Toru Tazawa 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: 20200326665
    Abstract: An electric motor control device that drives a control target load (mechanical load) includes a feedforward controller, a feedback controller, and an adder-subtractor. The feedforward controller receives a position command signal to specify a target position of the control target load and outputs a feedforward position command signal representing a target position of the electric motor, a feedforward speed command signal representing a target speed of the electric motor, and a feedforward torque command signal representing a torque necessary for the electric motor to perform an operation indicated by the target position or the target speed.
    Type: Application
    Filed: June 26, 2020
    Publication date: October 15, 2020
    Inventors: HIROSHI FUJIWARA, TORU TAZAWA
  • Publication number: 20200319622
    Abstract: An electric motor control device includes a position controller, a command acceleration calculator, a first subtractor, and a second subtractor. The position controller receives a position command signal specifying a target position of the load and an electric motor position signal representing a position of the electric motor that drives the load, and outputs a torque command signal. The command acceleration calculator receives the position command signal and outputs a command acceleration signal representing acceleration of the position command signal. The first subtractor subtracts the command acceleration signal from a load acceleration signal representing acceleration of the load and outputs a load acceleration correction signal. The second subtractor subtracts from the torque command signal a value obtained by multiplying the load acceleration correction signal by a predetermined weighting coefficient and outputs a torque command correction signal.
    Type: Application
    Filed: December 19, 2018
    Publication date: October 8, 2020
    Inventors: HIROSHI FUJIWARA, TORU TAZAWA
  • Patent number: 10715076
    Abstract: The invention provides a motor control device configured to feedback-control state quantity of a motor or a load, the device including a first notch filter disposed inside a feedback control system and configured to change a frequency component to be removed, a first notch controller configured to change a first notch frequency as a center frequency of the first notch filter, and a change forecaster configured to calculate to output, in accordance with the first notch frequency at each of a plurality of past times, at least one of a forecast value of the notch frequency at a specific future time, a forecast value of elapsed time from current time until the notch frequency is to become out of a specific frequency range, and a forecast value of time when the notch frequency is to become out of the specific frequency range.
    Type: Grant
    Filed: July 26, 2017
    Date of Patent: July 14, 2020
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Hiroshi Fujiwara, Toru Tazawa, Fumitake Saegusa
  • Patent number: 10715075
    Abstract: A motor control device is configured to feedback-control state quantity of a motor or a mechanical load, and the device includes a first notch filter disposed inside a feedback control system and configured to change a frequency component to be removed, a first notch controller configured to change a first notch frequency as a center frequency of the first notch filter, a change rate calculator configured to successively calculate a notch frequency change rate indicating a change amount per unit time of the first notch frequency, and a change rate monitor configured to output a signal indicating that the notch frequency change rate has a value outside a first predetermined range when the notch frequency change rate has the value outside the first predetermined range.
    Type: Grant
    Filed: July 28, 2017
    Date of Patent: July 14, 2020
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Hiroshi Fujiwara, Toru Tazawa, Fumitake Saegusa
  • Publication number: 20200083834
    Abstract: An electric motor control device performing feedback control of a state amount of an electric motor or a load and being capable of changing a control bandwidth of a feedback control system includes: a notch filter arranged in the feedback control system and having a filter coefficient which is changeable; a notch control section which changes a notch frequency as a center frequency of the notch filter to remove an oscillation component attributable to mechanical resonance related to the electric motor; and a control coefficient setting section which changes at least one of the control bandwidth or the filter coefficient of the notch filter in accordance with the control bandwidth and the notch frequency to stabilize the feedback control system.
    Type: Application
    Filed: May 18, 2018
    Publication date: March 12, 2020
    Applicant: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Hiroshi FUJIWARA, Toru TAZAWA, Fumitake SAEGUSA
  • Patent number: 10579038
    Abstract: A method, according to the present invention, of adjusting control parameters used in a control apparatus of an electric motor includes the steps of: computing a first frequency characteristic (Step 1); computing a present speed-proportional gain range (Step 2); computing a present mechanical-system characteristic constant (Step 3); computing a present proportional gain range (Step 4); computing a secular characteristic (Step 5); computing a secular speed-proportional gain range (Step 6); computing a secular proportional gain range (Step 7); and selecting proportional gain values (Step 8).
    Type: Grant
    Filed: December 20, 2018
    Date of Patent: March 3, 2020
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Toru Tazawa, Hiroshi Fujiwara, Masaru Nishizono
  • Publication number: 20190207549
    Abstract: A motor control device is configured to feedback-control state quantity of a motor or a mechanical load, and the device includes a first notch filter disposed inside a feedback control system and configured to change a frequency component to be removed, a first notch controller configured to change a first notch frequency as a center frequency of the first notch filter, a change rate calculator configured to successively calculate a notch frequency change rate indicating a change amount per unit time of the first notch frequency, and a change rate monitor configured to output a signal indicating that the notch frequency change rate has a value outside a first predetermined range when the notch frequency change rate has the value outside the first predetermined range.
    Type: Application
    Filed: July 28, 2017
    Publication date: July 4, 2019
    Inventors: HIROSHI FUJIWARA, TORU TAZAWA, FUMITAKE SAEGUSA
  • Publication number: 20190199267
    Abstract: The invention provides a motor control device configured to feedback-control state quantity of a motor or a load, the device including a first notch filter disposed inside a feedback control system and configured to change a frequency component to be removed, a first notch controller configured to change a first notch frequency as a center frequency of the first notch filter, and a change forecaster configured to calculate to output, in accordance with the first notch frequency at each of a plurality of past times, at least one of a forecast value of the notch frequency at a specific future time, a forecast value of elapsed time from current time until the notch frequency is to become out of a specific frequency range, and a forecast value of time when the notch frequency is to become out of the specific frequency range.
    Type: Application
    Filed: July 26, 2017
    Publication date: June 27, 2019
    Inventors: HIROSHI FUJIWARA, TORU TAZAWA, FUMITAKE SAEGUSA
  • Publication number: 20190146453
    Abstract: A method, according to the present invention, of adjusting control parameters used in a control apparatus of an electric motor includes the steps of: computing a first frequency characteristic (Step 1); computing a present speed-proportional gain range (Step 2); computing a present mechanical-system characteristic constant (Step 3); computing a present proportional gain range (Step 4); computing a secular characteristic (Step 5); computing a secular speed-proportional gain range (Step 6); computing a secular proportional gain range (Step 7); and selecting proportional gain values (Step 8).
    Type: Application
    Filed: December 20, 2018
    Publication date: May 16, 2019
    Inventors: Toru TAZAWA, Hiroshi FUJIWARA, Masaru NISHIZONO
  • Patent number: 10197986
    Abstract: A method, according to the present invention, of adjusting control parameters used in a control apparatus of an electric motor includes the steps of: computing a first frequency characteristic (Step 1); computing a present speed-proportional gain range (Step 2); computing a present mechanical-system characteristic constant (Step 3); computing a present proportional gain range (Step 4); computing a secular characteristic (Step 5); computing a secular speed-proportional gain range (Step 6); computing a secular proportional gain range (Step 7); and selecting proportional gain values (Step 8).
    Type: Grant
    Filed: May 25, 2018
    Date of Patent: February 5, 2019
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Toru Tazawa, Hiroshi Fujiwara, Masaru Nishizono
  • Publication number: 20180275628
    Abstract: A method, according to the present invention, of adjusting control parameters used in a control apparatus of an electric motor includes the steps of: computing a first frequency characteristic (Step 1); computing a present speed-proportional gain range (Step 2); computing a present mechanical-system characteristic constant (Step 3); computing a present proportional gain range (Step 4); computing a secular characteristic (Step 5); computing a secular speed-proportional gain range (Step 6); computing a secular proportional gain range (Step 7); and selecting proportional gain values (Step 8).
    Type: Application
    Filed: May 25, 2018
    Publication date: September 27, 2018
    Inventors: Toru Tazawa, Hiroshi Fujiwara, Masaru Nishizono
  • Patent number: 10007249
    Abstract: A method, according to the present invention, of adjusting control parameters used in a control apparatus of an electric motor includes the steps of: computing a first frequency characteristic (Step 1); computing a present speed-proportional gain range (Step 2); computing a present mechanical-system characteristic constant (Step 3); computing a present proportional gain range (Step 4); computing a secular characteristic (Step 5); computing a secular speed-proportional gain range (Step 6); computing a secular proportional gain range (Step 7); and selecting proportional gain values (Step 8).
    Type: Grant
    Filed: February 18, 2015
    Date of Patent: June 26, 2018
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Toru Tazawa, Hiroshi Fujiwara, Masaru Nishizono
  • Patent number: 9929683
    Abstract: Provided is a motor drive device which performs switching, with respect to a synchronous motor including a stator around which a motor winding is wound and a rotor holding a permanent magnet, from a synchronous operation in which the synchronous motor is synchronously driven to position-sensorless vector control in which a current supplied to the motor winding is controlled based on a position of the rotor. During the synchronous operation, the present motor drive device calculates, by estimation, an induced voltage error based on the detected current and voltage, performs control of an amplitude of a current instruction such that an error, of a target induced voltage, calculated based on an estimated induced voltage and based on an internal angle becomes equal to the induced voltage error, and switches the mode to the sensorless mode after the error is reduced to be within a range of a predetermined value.
    Type: Grant
    Filed: August 28, 2015
    Date of Patent: March 27, 2018
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Daisuke Sonoda, Mitsuhiro Sakamoto, Toru Tazawa
  • Publication number: 20170350404
    Abstract: A motor controller of the present invention comprises units which obtain information indicative of a motor speed (?) and information indicative of motor torque (T), an air flow calculation section which calculates an air flow (Q) of a fan based on the motor speed (?) and the motor torque (T); and a speed command generation section which generates a speed command (?*) of a motor such that the air flow (Q) coincides with the predetermined air flow command (Q*).
    Type: Application
    Filed: August 25, 2017
    Publication date: December 7, 2017
    Inventors: Ryuta SASAKI, Yasuyuki YOKOUCHI, Yasushi KATO, Toru TAZAWA
  • Patent number: 9771944
    Abstract: A motor controller of the present invention comprises units which obtain information indicative of a motor speed (?) and information indicative of motor torque (T), an air flow calculation section which calculates an air flow (Q) of a fan based on the motor speed (?) and the motor torque (T); and a speed command generation section which generates a speed command (?*) of a motor such that the air flow (Q) coincides with the predetermined air flow command (Q*).
    Type: Grant
    Filed: September 13, 2012
    Date of Patent: September 26, 2017
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Ryuta Sasaki, Yasuyuki Yokouchi, Yasushi Kato, Toru Tazawa
  • Publication number: 20170214343
    Abstract: Provided is a motor drive device which performs switching, with respect to a synchronous motor including a stator around which a motor winding is wound and a rotor holding a permanent magnet, from a synchronous operation in which the synchronous motor is synchronously driven to position-sensorless vector control in which a current supplied to the motor winding is controlled based on a position of the rotor. During the synchronous operation, the present motor drive device calculates, by estimation, an induced voltage error based on the detected current and voltage, performs control of an amplitude of a current instruction such that an error, of a target induced voltage, calculated based on an estimated induced voltage and based on an internal angle becomes equal to the induced voltage error, and switches the mode to the sensorless mode after the error is reduced to be within a range of a predetermined value.
    Type: Application
    Filed: August 28, 2015
    Publication date: July 27, 2017
    Inventors: DAISUKE SONODA, MITSUHIRO SAKAMOTO, TORU TAZAWA
  • Publication number: 20160313721
    Abstract: A method, according to the present invention, of adjusting control parameters used in a control apparatus of an electric motor includes the steps of: computing a first frequency characteristic (Step 1); computing a present speed-proportional gain range (Step 2); computing a present mechanical-system characteristic constant (Step 3); computing a present proportional gain range (Step 4); computing a secular characteristic (Step 5); computing a secular speed-proportional gain range (Step 6); computing a secular proportional gain range (Step 7); and selecting proportional gain values (Step 8).
    Type: Application
    Filed: February 18, 2015
    Publication date: October 27, 2016
    Applicant: Panasonic Intellecyual Property Management Co., Lt
    Inventors: TORU TAZAWA, HIROSHI FUJIWARA, MASARU NISHIZONO
  • Patent number: 9065380
    Abstract: A method for calculating a motor constant of a permanent magnet type synchronous motor according to the present invention includes: a voltage applying step of applying a voltage obtained by compositing a DC component and an AC component to a permanent magnet type synchronous motor while varying a frequency of the AC component; a current detecting step of detecting a motor current flowing according to the applied voltage; a phase difference calculating step of calculating a difference in phase between the AC component of the applied voltage and an AC component of the motor current; and a motor constant calculating step of calculating a motor constant of the permanent magnet type synchronous motor. In addition, in the motor constant calculating step, the motor constant is calculated based on the applied voltage and the motor current when the difference in phase becomes nearly 45 degrees.
    Type: Grant
    Filed: July 30, 2012
    Date of Patent: June 23, 2015
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Toru Tazawa, Masaru Nishizono
  • Patent number: 9024552
    Abstract: The present invention includes a voltage applying step of applying an applied voltage including a DC component and a plurality of frequency components to a PM motor, a motor current detecting step of detecting a motor current flowing depending on the applied voltage, and a current control gain adjusting step of calculating a current control gain based on frequency characteristics of the applied voltage and the motor current. In this manner, a stable current control gain having a high current response can be adjusted within a short period of time.
    Type: Grant
    Filed: September 28, 2011
    Date of Patent: May 5, 2015
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Toru Tazawa, Masaru Nishizono
  • Patent number: 9024562
    Abstract: A motor constant calculating method for a PM motor according to the present invention includes a voltage applying step of applying an applied voltage including a DC component and a plurality of frequency components to a PM motor, a motor current detecting step of detecting a motor current flowing depending on the applied voltage applied in the voltage applying step, and a motor constant calculating step of calculating a motor constant of the PM motor based on the applied voltage and the motor current.
    Type: Grant
    Filed: September 28, 2011
    Date of Patent: May 5, 2015
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Toru Tazawa, Masaru Nishizono