Patents by Inventor Mikio MORISHIMA

Mikio MORISHIMA 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: 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: 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: 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: 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