Patents by Inventor Takashi KOIKEGAMI

Takashi KOIKEGAMI 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: 11870375
    Abstract: A motor apparatus is provided. The motor apparatus includes a motor having a rotor and a stator, an inverter used to covert an input voltage into a three-phase alternating current (AC) voltage and provide the three-phase AC voltage to the motor, an inverter controller used to control the inverter, and a rotation angle sensor. The rotation angle sensor is fixed to the motor and is used to detect a rotation angle of the motor. The inverter controller includes a calculator. The calculator calculates an offset angle of an installation position of the rotation angle sensor according to a difference between a measured value and a theoretical value of a voltage phase of the motor.
    Type: Grant
    Filed: April 6, 2022
    Date of Patent: January 9, 2024
    Assignee: NIDEC ELESYS CORPORATION
    Inventors: Takashi Koikegami, Satoshi Shimazu, Yuhi Nakada
  • Publication number: 20220416712
    Abstract: A motor control device includes an inverter circuit to convert a DC power source voltage into a three-phase AC voltage and supply the three-phase AC voltage to the three-phase motor and a controller to generate three-phase PWM signals based on three-phase duty command values updated at a predetermined updating cycle and control the inverter circuit based on the three-phase PWM signals. The controller is configured or programmed to shift, when duty command values of at least two phases of the three-phase duty command values updated at a first update timing are the same, the duty command value of one phase of the duty command values of the two phases by a predetermined shift amount and shifts a duty command value of the one phase of the three-phase duty command values updated at a second update timing which is an update timing next to the first update timing by the shift amount in a direction opposite to a shift direction at the first update timing.
    Type: Application
    Filed: June 23, 2022
    Publication date: December 29, 2022
    Inventors: Takashi KOIKEGAMI, Isao SANBONMATSU, Akihiro OKAMURA, Tomohiro FUKUMURA, Kotaro KATAOKA
  • Patent number: 11472472
    Abstract: A power conversion device includes a first inverter and a control circuit that controls an on/off operations of switches in the first inverter and diagnoses disconnection failures of n-phase windings, where n is an integer of three or more. The control circuit generates a control signal to turn off all of n low-side switches and n high-side switches, supplies the control signal to the n low-side switches and the n high-side switches and measures the n-phase voltages that change depending on patterns of on failures of the switches, and executes a first failure diagnosis to diagnose the on failures of the n low-side switches and the n high-side switches based on the measured n-phase voltages by referring to a table associating the patterns of the on failures of the switches with n-phase voltage levels.
    Type: Grant
    Filed: June 22, 2018
    Date of Patent: October 18, 2022
    Assignee: NIDEC CORPORATION
    Inventors: Takashi Koikegami, Yuhi Nakada, Kaori Nabeshi
  • Publication number: 20220329185
    Abstract: A motor apparatus is provided. The motor apparatus includes a motor having a rotor and a stator, an inverter used to covert an input voltage into a three-phase alternating current (AC) voltage and provide the three-phase AC voltage to the motor, an inverter controller used to control the inverter, and a rotation angle sensor. The rotation angle sensor is fixed to the motor and is used to detect a rotation angle of the motor. The inverter controller includes a calculator. The calculator calculates an offset angle of an installation position of the rotation angle sensor according to a difference between a measured value and a theoretical value of a voltage phase of the motor.
    Type: Application
    Filed: April 6, 2022
    Publication date: October 13, 2022
    Applicant: NIDEC ELESYS CORPORATION
    Inventors: Takashi Koikegami, Satoshi Shimazu, Yuhi Nakada
  • Patent number: 11063545
    Abstract: A power conversion device includes a first inverter and a control circuit that controls on/off operations of switches in the first inverter and diagnoses disconnection failures of n-phase windings where n is an integer of three or more. The control circuit generates a control signal to turn on one low-side switch of a first specific phase among n low-side switch in the first inverter, turn off the remaining n?1 low-side switches, and turn off all n high-side switches, supplies the control signal to the n low-side switches and the n high-side switches in a state where a neutral point of a motor is provided, measures n-phase voltages that change depending on patterns of disconnection failures of the n-phase windings, and diagnoses a disconnection failure based on the measured n-phase voltages by referring to a table associating the patterns of the disconnection failures with n-phase voltage levels.
    Type: Grant
    Filed: July 10, 2018
    Date of Patent: July 13, 2021
    Assignee: NIDEC CORPORATION
    Inventors: Takashi Koikegami, Yuhi Nakada, Takahiro Kikuichi, Jun Katsumata, Hironori Takano
  • Publication number: 20200274461
    Abstract: An electric power conversion device includes a first inverter connected to one end of each phase winding of a motor, a second inverter connected to another end of each phase winding, and a control circuit to control operation of the first and second inverters. The control circuit configures a neutral point in the first inverter and applies a voltage to a path in which a high-side of the second inverter, the first-phase winding, the neutral point, the second-phase winding, and a low-side of the second inverter are connected, and diagnoses whether the first and second inverters are faulty.
    Type: Application
    Filed: June 11, 2018
    Publication date: August 27, 2020
    Inventors: Takashi KOIKEGAMI, Yuhi NAKADA, Takahiro KIKUICHI
  • Publication number: 20200247464
    Abstract: A power conversion device includes a first inverter and a control circuit that controls an on/off operations of switches in the first inverter and diagnoses disconnection failures of n-phase windings, where n is an integer of three or more. The control circuit generates a control signal to turn off all of n low-side switches and n high-side switches, supplies the control signal to the n low-side switches and the n high-side switches and measures the n-phase voltages that change depending on patterns of on failures of the switches, and executes a first failure diagnosis to diagnose the on failures of the n low-side switches and the n high-side switches based on the measured n-phase voltages by referring to a table associating the patterns of the on failures of the switches with n-phase voltage levels.
    Type: Application
    Filed: June 22, 2018
    Publication date: August 6, 2020
    Inventors: Takashi KOIKEGAMI, Yuhi NAKADA, Kaori NABESHI
  • Publication number: 20200186075
    Abstract: A power conversion device includes a first inverter and a control circuit that controls on/off operations of switches in the first inverter and diagnoses disconnection failures of n-phase windings where n is an integer of three or more. The control circuit generates a control signal to turn on one low-side switch of a first specific phase among n low-side switch in the first inverter, turn off the remaining n?1 low-side switches, and turn off all n high-side switches, supplies the control signal to the n low-side switches and the n high-side switches in a state where a neutral point of a motor is provided, measures n-phase voltages that change depending on patterns of disconnection failures of the n-phase windings, and diagnoses a disconnection failure based on the measured n-phase voltages by referring to a table associating the patterns of the disconnection failures with n-phase voltage levels.
    Type: Application
    Filed: July 10, 2018
    Publication date: June 11, 2020
    Inventors: Takashi KOIKEGAMI, Yuhi NAKADA, Takahiro KIKUICHI, Jun KATSUMATA, Hironori TAKANO
  • Publication number: 20190334465
    Abstract: A motor drive includes limiting circuitry that controls a motor based on an instruction torque, and calculates a limitation rate that limits the instruction torque. The instruction torque is limited based on the limitation rate calculated by the limiting circuitry. The motor drive also includes a controller that outputs electric power to drive the motor based on the limited instruction torque.
    Type: Application
    Filed: April 24, 2019
    Publication date: October 31, 2019
    Inventors: Yuhi NAKADA, Takashi KOIKEGAMI, Isao SAMBOMMATSU, Koji MUKAIYAMA