Patents Assigned to Tabuchi Electric Co., Ltd.
  • Patent number: 10897213
    Abstract: A power converter includes: an inverter converting DC power to AC power and outputting the AC power to first and second voltage terminals of a connection terminal unit; and switches RC. The switches RC include a first protection switch provided to a first line connecting the inverter and the first voltage terminal together, a second protection switch provided to a second line connecting the inverter and the second voltage terminal together, and a voltage switch connected in series between the second line and a neutral terminal. A load connection terminal is connected to a line connecting between the first line and the voltage switch.
    Type: Grant
    Filed: April 18, 2018
    Date of Patent: January 19, 2021
    Assignee: TABUCHI ELECTRIC CO., LTD.
    Inventor: Akihiko Hosokawa
  • Patent number: 10797485
    Abstract: In a conventional power supply system, it was difficult to quickly activate a motor load or the like after performing switching to an isolated operation.
    Type: Grant
    Filed: March 10, 2017
    Date of Patent: October 6, 2020
    Assignee: TABUCHI ELECTRIC CO., LTD.
    Inventors: Yuji Yamauchi, Hiroshi Asano, Masataka Shintani, Hirofumi Konishi
  • Patent number: 10777911
    Abstract: Provided are an electric cable connecting terminal reducing unwanted overflow of solder out of an electric cable connecting portion to a connector portion during soldering, and a method for joining an electric cable connecting terminal and an electric cable. An electric cable connecting terminal for electrically connecting an electric cable to an external conductor includes a connector portion to be attached to the conductor, and an electric cable connecting portion having a connecting surface to which the electric cable, which is a bundle of core wires, is connected by soldering. The electric cable connecting portion includes a crimp portion to be swaged to hold the electric cable, and a step portion protruding from the connecting surface between the connector portion and the crimp portion.
    Type: Grant
    Filed: May 16, 2016
    Date of Patent: September 15, 2020
    Assignee: TABUCHI ELECTRIC CO., LTD.
    Inventors: Akimasa Tamura, Atsushi Kawabata, Kazusa Mori, Kazuhiro Matsui
  • Patent number: 10536000
    Abstract: A grid independent operation control unit includes a load current estimator to estimate a load current supplied to stand-alone power system in accordance with an output current of the inverter and an output voltage, and a feedback controller configured to PWM control the inverter at a duty ratio feedback calculated to cause the inverter to output an output voltage command value in accordance with the output voltage and the load current. The feedback controller is configured to PWM control the inverter at a duty ratio feedback calculated for output of a normalized output voltage command value obtained by normalizing the output voltage command value with the DC bus voltage in accordance with normalized output voltage obtained by normalizing the output voltage with the DC bus voltage and normalized load current obtained by normalizing the load current with the DC bus voltage.
    Type: Grant
    Filed: February 10, 2016
    Date of Patent: January 14, 2020
    Assignee: TABUCHI ELECTRIC CO., LTD.
    Inventors: Chienru Lung, Hideki Hidaka
  • Patent number: 10418812
    Abstract: An abnormality detection device for a grid interconnection relay to detect an abnormality of the grid interconnection relay upon switching to grid independent operation, and includes an abnormality detector to execute commercial power system voltage determination of determining whether or not there is a commercial power system voltage, and first voltage determination to be executed if it is determined that there is no commercial power system voltage through the commercial power system voltage determination, of causing the power conditioner to chronologically alternately output monitor voltages having different values in a state where a contact of the grid interconnection relay is controlled to open and executing abnormality determination as to the grid interconnection relay according to whether or not each of the monitor voltages is followed by difference between a voltage of the power conditioner and voltage of the commercial power system with respect to corresponding one of the monitor voltages.
    Type: Grant
    Filed: November 26, 2015
    Date of Patent: September 17, 2019
    Assignee: TABUCHI ELECTRIC CO., LTD.
    Inventors: Chienru Lung, Hideki Hidaka
  • Patent number: 10411478
    Abstract: A grid connection power conversion device having isolated operation function for connecting a distributed power supply to a commercial power system is provided which comprises an inverter for converting DC power to AC power, a capacitor connected between the inverter and the commercial power system, a commercial voltage amplitude detection circuitry, an amplitude adjustment circuitry to increase an amplitude of an output voltage from the inverter stepwise from a given value to match the amplitude of the commercial system voltage, and a start-up control circuitry to control the grid connection power conversion device so that after the amplitude adjustment circuitry adjusts the amplitude of the output voltage from the inverter, after the start-up, to match the amplitude of the commercial system voltage detected by the commercial voltage amplitude detection circuitry, the start-up control circuitry connects the inverter to the commercial power system to start grid-connected operation.
    Type: Grant
    Filed: January 9, 2017
    Date of Patent: September 10, 2019
    Assignee: Tabuchi Electric Co., Ltd.
    Inventors: Chienru Lung, Hideki Hidaka
  • Patent number: 10381153
    Abstract: Disclosed herein is a spacer fixing structure including a core member constituting a core to be wound with a coil; and a plate spacer fixed to the core member. The spacer has a loop shape. A communication groove is formed in at least one surface of front and back surfaces of the spacer, and extends radially to communicate with inner and outer peripheries of the spacer. A region of the at least one surface of the spacer other than a grooved portion is left as a flat surface. At least the flat surface of the spacer is adhered to the core member via an adhesive layer made of an adhesive.
    Type: Grant
    Filed: January 13, 2017
    Date of Patent: August 13, 2019
    Assignee: TABUCHI ELECTRIC CO., LTD.
    Inventor: Keisuke Honda
  • Patent number: 10298148
    Abstract: Provided are: a smoothing capacitor connected in parallel to the DC power source; a bridge circuit including switching elements for converting DC power to AC power, flywheel diodes connected in reversely parallel, and flywheel-and-separation diodes connected in series to the flywheel diodes and serving concurrently as flywheel and separation diodes; an interconnection reactor on an output side, provided on AC output lines connecting the bridge circuit and an AC power source; and a separation circuit for separating the smoothing capacitor and the interconnection reactor from each other during a flywheel period of the flywheel diodes. The separation circuit includes separation switching elements and the flywheel-and-separation diodes. The separation switching elements are respectively connected between the two AC output lines and two series connection points between the flywheel diodes and the flywheel-and-separation diodes, so as to short-circuit the AC output lines.
    Type: Grant
    Filed: February 16, 2016
    Date of Patent: May 21, 2019
    Assignee: TABUCHI ELECTRIC CO., LTD.
    Inventor: Hidehiko Sugimoto
  • Publication number: 20190109458
    Abstract: In a conventional power supply system, it was difficult to quickly activate a motor load or the like after performing switching to an isolated operation.
    Type: Application
    Filed: March 10, 2017
    Publication date: April 11, 2019
    Applicant: TABUCHI ELECTRIC CO., LTD.
    Inventors: Yuji YAMAUCHI, Hiroshi ASANO, Masataka SHINTANI, Hirofumi KONISHI
  • Patent number: 10236793
    Abstract: A grid connection power conversion device for connecting a distributed power supply to a three-phase commercial power system is provided. The power conversion device comprises an inverter, an instantaneous voltage detection circuitry to detect a maximum three-phase instantaneous voltage value of the commercial power system, a line voltage detection circuitry to detect a maximum value of each of three line voltages, an instantaneous voltage drop detection circuitry to detect an instantaneous voltage drop, and an output current control circuitry to control an output current value from the inverter. When the instantaneous voltage drop detection circuitry detects an instantaneous voltage drop, the output current control circuitry reduces the output current value from the inverter to an output current value corresponding to a minimum value among the four maximum voltage values which are the maximum three-phase instantaneous voltage value and the maximum values of the three line voltages.
    Type: Grant
    Filed: June 2, 2017
    Date of Patent: March 19, 2019
    Assignee: Tabuchi Electric Co., Ltd.
    Inventors: Chienru Lung, Hideki Hidaka
  • Patent number: 10218261
    Abstract: A grid connection power conversion device is provided in which an amplitude of an output voltage from an inverter is increased stepwise from 0, after start-up of the power conversion device, to adjust the amplitude of the output voltage from the inverter to match an amplitude of a commercial system voltage as detected, and thereafter the inverter is connected to the commercial power system to start grid-connected operation. This makes it possible to prevent the voltage applied to a capacitor provided between the inverter and the commercial power system from abruptly increasing from 0V to the commercial system voltage at the start-up of the power conversion device, thereby making it possible to reduce an inrush current to the capacitor at the start-up without using an inrush current prevention circuitry.
    Type: Grant
    Filed: February 15, 2017
    Date of Patent: February 26, 2019
    Assignee: Tabuchi Electric Co., Ltd.
    Inventors: Chienru Lung, Hideki Hidaka
  • Publication number: 20180309387
    Abstract: A power converter includes: an inverter converting DC power to AC power and outputting the AC power to first and second voltage terminals of a connection terminal unit; and switches RC. The switches RC include a first protection switch provided to a first line connecting the inverter and the first voltage terminal together, a second protection switch provided to a second line connecting the inverter and the second voltage terminal together, and a voltage switch connected in series between the second line and a neutral terminal. A load connection terminal is connected to a line connecting between the first line and the voltage switch.
    Type: Application
    Filed: April 18, 2018
    Publication date: October 25, 2018
    Applicant: TABUCHI ELECTRIC CO., LTD.
    Inventor: Akihiko HOSOKAWA
  • Publication number: 20180151962
    Abstract: Provided are an electric cable connecting terminal reducing unwanted overflow of solder out of an electric cable connecting portion to a connector portion during soldering, and a method for joining an electric cable connecting terminal and an electric cable. An electric cable connecting terminal for electrically connecting an electric cable to an external conductor includes a connector portion to be attached to the conductor, and an electric cable connecting portion having a connecting surface to which the electric cable, which is a bundle of core wires, is connected by soldering. The electric cable connecting portion includes a crimp portion to be swaged to hold the electric cable, and a step portion protruding from the connecting surface between the connector portion and the crimp portion.
    Type: Application
    Filed: May 16, 2016
    Publication date: May 31, 2018
    Applicant: TABUCHI ELECTRIC CO., LTD.
    Inventors: Akimasa Tamura, Atsushi Kawabata, Kazusa Mori, Kazuhiro Matsui
  • Patent number: 9977094
    Abstract: An islanding operation detection device for a distributed power supply comprising an inverter connected to a commercial system power supply comprises: a commercial system frequency measurement circuitry; a reactive power injection amount calculation circuitry to calculate an amount of reactive power injection; a feedback signal generation circuitry; a reactive current control circuitry to feedback-control an output current command value to the inverter; an output current control circuitry to update the reactive current command value when a phase angle of the commercial system voltage is in the range of 90N°±?? so as to control an output current value of the inverter to follow the output current command value; and an islanding operation detection circuitry to detect whether or not the distributed power supply is in islanding mode, based on a commercial system frequency when the reactive power corresponding to the calculated amount of reactive power injection is injected.
    Type: Grant
    Filed: January 9, 2017
    Date of Patent: May 22, 2018
    Assignee: Tabuchi Electric Co., Ltd.
    Inventors: Chienru Lung, Hideki Hidaka
  • Patent number: 9970988
    Abstract: A relay abnormality detection device to detect an abnormality of a grid interconnection relay upon switching to grid independent operation and includes an abnormality detector to execute commercial power system voltage for determining whether or not there is a commercial power system voltage, if there is commercial power system voltage through the commercial power system voltage determination, first current determination of abnormality determination as to the specific relay according to whether or not there is an input current to the power conditioner in a state where a contact of the specific relay is controlled to open, and if there is no commercial power system voltage through commercial power system voltage determination, second current determination of abnormality determination as to the specific relay according to whether or not there is an output current from the power conditioner in the state where the contact of the specific relay is controlled to open.
    Type: Grant
    Filed: November 20, 2015
    Date of Patent: May 15, 2018
    Assignee: TABUCHI ELECTRIC CO., LTD.
    Inventors: Chienru Lung, Hideki Hidaka
  • Patent number: 9906070
    Abstract: The present system 1 includes a distributed power source 2, a storage battery 4, a bidirectional inverter 7 having a smoothing capacitor 6 on its DC side, and a control section 10 for controlling the entire system, and supplies AC power to a load 9 while being interconnected with a power system 8. When active power supplied from the distributed power source 2 and/or the storage battery 4 to the smoothing capacitor 6 is equal to or greater than active power of load power, the control section 10 controls a power factor of inverter output current outputted from the bidirectional inverter 7 so as to coincide with a power factor of load current flowing to the load 9.
    Type: Grant
    Filed: November 19, 2015
    Date of Patent: February 27, 2018
    Assignee: Tabuchi Electric Co., Ltd.
    Inventor: Hidehiko Sugimoto
  • Patent number: 9899748
    Abstract: A terminal connection structure for an electric wire end portion (12a) in which the electric wire end portion is soldered being exposed on a flat-plate terminal piece (11b) out from inside of a terminal main part (11a), the terminal piece being continuous with a front end of the terminal main part (11a). The electric wire end portion (12a) exposed on the terminal piece (11b) from the terminal main part (11a) includes a first end section (12a1) that is close to the terminal main part (11a) and a second end section (12a2) that is far from the terminal main part (11a). The electric wire end portion (12a) has a shape, in side view, such that the first end section (12a1) is compressed to have a gentle curved surface that approaches the terminal piece (11b) toward the second end section (12a2).
    Type: Grant
    Filed: January 30, 2017
    Date of Patent: February 20, 2018
    Assignee: Tabuchi Electric Co., Ltd.
    Inventor: Takenori Kunimi
  • Patent number: D805031
    Type: Grant
    Filed: August 31, 2015
    Date of Patent: December 12, 2017
    Assignee: TABUCHI ELECTRIC CO., LTD.
    Inventors: Shinichi Yamasaki, Toshihiro Kawasaki
  • Patent number: D806028
    Type: Grant
    Filed: July 11, 2016
    Date of Patent: December 26, 2017
    Assignee: TABUCHI ELECTRIC CO., LTD.
    Inventor: Hirohito Amasaki
  • Patent number: D842807
    Type: Grant
    Filed: November 4, 2016
    Date of Patent: March 12, 2019
    Assignee: TABUCHI ELECTRIC CO., LTD.
    Inventor: Hirohito Amasaki