Patents by Inventor Qichen WANG

Qichen WANG 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: 20230369142
    Abstract: A semiconductor device includes a first input conductive plate on which a plurality of first semiconductor chips arranged in a first direction, a first output conductive plate extending in the first direction and being provided adjacent to the first input conductive plate, a case having first to fourth side walls for accommodating the first input conductive plate and the first output conductive plate, first main current wiring members, each of which connects one of the first output electrodes to a front surface of the first output conductive plate, a first detection terminal disposed in the first side wall, and a first detection wiring member connecting the front surface of the first output conductive plate to the first detection terminal. The first output conductive plate is disposed closer to the first side wall than is the first input conductive plate.
    Type: Application
    Filed: March 9, 2023
    Publication date: November 16, 2023
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Motohito HORI, Yoshinari IKEDA, Takaaki TANAKA, Qichen WANG
  • Patent number: 11632038
    Abstract: A snubber apparatus includes N parallel charge paths, each of which has a positive-side capacitor, a first diode, and a negative-side capacitor sequentially connected in series between a positive-side terminal and a negative-side terminal, and that allows current to flow from the positive-side terminal's side to the negative-side terminal's side. The snubber apparatus includes N+1 parallel discharge paths, each of which has a second diode connected between the negative-side terminal or the negative-side capacitor in the k-th charge path of the N charge paths, and the positive-side capacitor in the (k+1)-th charge path of the N charge paths or the positive-side terminal, and that allows current to flow from the negative-side terminal's side to the positive-side terminal's side via at least one of the negative-side capacitor and the positive-side capacitor. At least one of the charge paths has a plurality of sections that are turned and adjacent to each other.
    Type: Grant
    Filed: November 25, 2021
    Date of Patent: April 18, 2023
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Qichen Wang, Ryuji Yamada
  • Patent number: 11424610
    Abstract: A conventional technique makes a configuration complicated. Provided is an apparatus including: a voltage measuring unit configured to measure each of instantaneous voltages of three-phase AC voltage; and a determination unit configured to determine a state of a power supply source of the three-phase AC voltage based on a result of comparison between a comparison target value corresponding to a sum of n-th powers (n is a positive even number) of the instantaneous voltages of the three-phase AC voltage and a reference value.
    Type: Grant
    Filed: September 30, 2019
    Date of Patent: August 23, 2022
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Qichen Wang, Nobuyuki Tawada
  • Publication number: 20220224221
    Abstract: Provided is a snubber apparatus comprising: N parallel charge paths, each of which has a positive-side capacitor, a first diode, and a negative-side capacitor sequentially connected in series between a positive-side terminal and a negative-side terminal, and that allows current to flow from the positive-side terminal's side to the negative-side terminal's side; and N+1 parallel discharge paths, each of which has a second diode connected between the negative-side terminal or the negative-side capacitor in the k-th charge path of the N charge paths, and the positive-side capacitor in the (k+1)-th charge path of the N charge paths or the positive-side terminal, and that allows current to flow from the negative-side terminal's side to the positive-side terminal's side via at least one of the negative-side capacitor and the positive-side capacitor, at least one of the charge paths having a plurality of sections are turned and adjacent to each other.
    Type: Application
    Filed: November 25, 2021
    Publication date: July 14, 2022
    Inventors: Qichen WANG, Ryuji YAMADA
  • Patent number: 11218070
    Abstract: A snubber module is provided, which constitutes a snubber apparatus attachable to a terminal of a semiconductor module.
    Type: Grant
    Filed: February 24, 2020
    Date of Patent: January 4, 2022
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Qichen Wang, Ryuji Yamada
  • Patent number: 11165333
    Abstract: A snubber device to be mounted to a terminal of a semiconductor module is provided. The snubber device includes n (n: integer of 1 or greater) parallel charge paths each having a positive-side capacitor, a first diode, and a negative-side capacitor sequentially connected in series between positive-side and negative-side terminals of the semiconductor module, and configured to enable current to flow from the positive-side terminal toward the negative-side terminal; and (n+1) parallel discharge paths each of which having a second diode connected between the negative-side terminal or the negative-side capacitor of an Nth charge path (N: integer within a range of 0?N?n) of then charge paths and the positive-side capacitor of a (N+1)th charge path of the n charge paths or the positive-side terminal, and configured to enable current to flow from the negative-side terminal toward the positive-side terminal via at least one of the negative-side and positive-side capacitors.
    Type: Grant
    Filed: November 25, 2019
    Date of Patent: November 2, 2021
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Ryuji Yamada, Qichen Wang, Kazuyuki Yoda
  • Patent number: 10825605
    Abstract: A transformer includes: a core having a shaft; primary windings; and secondary windings around the shaft alternately with the primary windings. A first number of turns of a first secondary winding, closest to a first end of the shaft, is less than a second number of turns of a second secondary winding, second closest to the first end. A third number of turns of a third secondary winding, closest to a second end of the shaft, is less than a fourth number of turns of a fourth secondary winding, second closest to the second end. The first and second windings are connected in series. The third and fourth windings are connected in series. The first and second windings are connected in parallel to the third and fourth windings. A total of the first and second numbers is equal to that of the third and fourth numbers.
    Type: Grant
    Filed: August 24, 2018
    Date of Patent: November 3, 2020
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Qichen Wang, Satoru Fujita
  • Publication number: 20200295652
    Abstract: A snubber module is provided, which constitutes a snubber apparatus attachable to a terminal of a semiconductor module.
    Type: Application
    Filed: February 24, 2020
    Publication date: September 17, 2020
    Inventors: Qichen WANG, Ryuji YAMADA
  • Publication number: 20200244158
    Abstract: A snubber device to be mounted to a terminal of a semiconductor module is provided. The snubber device includes n (n: integer of 1 or greater) parallel charge paths each having a positive-side capacitor, a first diode, and a negative-side capacitor sequentially connected in series between positive-side and negative-side terminals of the semiconductor module, and configured to enable current to flow from the positive-side terminal toward the negative-side terminal; and (n+1) parallel discharge paths each of which having a second diode connected between the negative-side terminal or the negative-side capacitor of an Nth charge path (N: integer within a range of 0?N?n) of then charge paths and the positive-side capacitor of a (N+1)th charge path of the n charge paths or the positive-side terminal, and configured to enable current to flow from the negative-side terminal toward the positive-side terminal via at least one of the negative-side and positive-side capacitors.
    Type: Application
    Filed: November 25, 2019
    Publication date: July 30, 2020
    Inventors: Ryuji YAMADA, Qichen WANG, Kazuyuki YODA
  • Publication number: 20200161851
    Abstract: A conventional technique makes a configuration complicated. Provided is an apparatus including: a voltage measuring unit configured to measure each of instantaneous voltages of three-phase AC voltage; and a determination unit configured to determine a state of a power supply source of the three-phase AC voltage based on a result of comparison between a comparison target value corresponding to a sum of n-th powers (n is a positive even number) of the instantaneous voltages of the three-phase AC voltage and a reference value.
    Type: Application
    Filed: September 30, 2019
    Publication date: May 21, 2020
    Inventors: Qichen WANG, Nobuyuki TAWADA
  • Patent number: 10398029
    Abstract: A transformer is configured to include a pair of cores and that each have an inner leg, wherein a primary winding that is wound around a bobbin having a hollow into which the inner legs of the cores and are inserted, and a secondary winding that has a hollow into which the inner legs of the cores and are inserted and that is constituted of a conductor formed by die-cutting a metal plate into a ring, are dispersedly arranged over the inner legs of the cores and. The bobbin has bobbin support portions that come into contact with a surface of a printed circuit board on which the transformer is implemented.
    Type: Grant
    Filed: May 1, 2017
    Date of Patent: August 27, 2019
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Qichen Wang, Satoru Fujita, Takashi Kuwabara, Nobuyuki Tawada
  • Publication number: 20190131062
    Abstract: A transformer includes: a core having a shaft; primary windings; and secondary windings around the shaft alternately with the primary windings. A first number of turns of a first secondary winding, closest to a first end of the shaft, is less than a second number of turns of a second secondary winding, second closest to the first end. A third number of turns of a third secondary winding, closest to a second end of the shaft, is less than a fourth number of turns of a fourth secondary winding, second closest to the second end. The first and second windings are connected in series. The third and fourth windings are connected in series. The first and second windings are connected in parallel to the third and fourth windings. A total of the first and second numbers is equal to that of the third and fourth numbers.
    Type: Application
    Filed: August 24, 2018
    Publication date: May 2, 2019
    Inventors: Qichen WANG, Satoru FUJITA
  • Patent number: 10122281
    Abstract: A power conversion device includes a potential variation suppression portion having first and second ground capacitors and a reactor, for suppressing a potential variations at an A point at which switching elements and are connected together and at a B point in a bidirectional switch. The potential variation suppression portion suppresses potential variation at the A point by cancelling a first leakage current, which flows due to the potential variation at the A point at the positive and negative polarities of an alternating current voltage, with a first compensating current flowing via the reactor and ground capacitor, and suppresses the potential variation at the B point by cancelling a second leakage current, which flows due to the potential variation at the B point at the negative polarity of the alternating current voltage, with a second compensating current flowing via the reactor, a switch, and the second ground capacitor.
    Type: Grant
    Filed: September 12, 2016
    Date of Patent: November 6, 2018
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Qichen Wang, Satoru Fujita
  • Patent number: 9887539
    Abstract: A power conversion device includes an AC power source configured to output an AC voltage, a DC power source configured to output a plurality of DC voltages having different levels, an inverter configured to receive the AC voltage and the plurality of DC voltages and output an output voltage by boosting the AC voltage in a booster mode in accordance with first and second control signals, the booster mode being a mode in which a level of the AC voltage is smaller than a predetermined value, a reactor configured to smooth the output voltage of the inverter, and a control circuit configured to generate the first and second control signals using a first and second carrier signals having different frequencies, respectively, in the booster mode, and selectively output the first or second control signal in accordance with the level of the AC voltage from the AC power source.
    Type: Grant
    Filed: October 7, 2015
    Date of Patent: February 6, 2018
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Qichen Wang, Satoru Fujita
  • Publication number: 20170367184
    Abstract: A transformer is configured to include a pair of cores and that each have an inner leg, wherein a primary winding that is wound around a bobbin having a hollow into which the inner legs of the cores and are inserted, and a secondary winding that has a hollow into which the inner legs of the cores and are inserted and that is constituted of a conductor formed by die-cutting a metal plate into a ring, are dispersedly arranged over the inner legs of the cores and. The bobbin has bobbin support portions that come into contact with a surface of a printed circuit board on which the transformer is implemented.
    Type: Application
    Filed: May 1, 2017
    Publication date: December 21, 2017
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Qichen WANG, Satoru FUJITA, Takashi KUWABARA, Nobuyuki TAWADA
  • Publication number: 20160380546
    Abstract: A power conversion device includes a potential variation suppression portion having first and second ground capacitors and a reactor, for suppressing a potential variations at an A point at which switching elements and are connected together and at a B point in a bidirectional switch. The potential variation suppression portion suppresses potential variation at the A point by cancelling a first leakage current, which flows due to the potential variation at the A point at the positive and negative polarities of an alternating current voltage, with a first compensating current flowing via the reactor and ground capacitor, and suppresses the potential variation at the B point by cancelling a second leakage current, which flows due to the potential variation at the B point at the negative polarity of the alternating current voltage, with a second compensating current flowing via the reactor, a switch, and the second ground capacitor.
    Type: Application
    Filed: September 12, 2016
    Publication date: December 29, 2016
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Qichen WANG, Satoru FUJITA
  • Patent number: 9531298
    Abstract: When in an operation mode in which an alternating current voltage Vout is output using a positive voltage V1 of a direct current power source 1 input via a switching element Q1, a negative voltage V2 of the direct current power source 1 input via a switching element Q2, and a zero voltage Vz input via a bidirectional switch element BS1 or an alternating current voltage Vs input via a bidirectional switch element BS2, in the period in which the polarity of the output voltage Vout and the polarity of an output current Iout are the same, a control signal of an element to be caused to perform an on/off operation is generated by being pulse-width modulated using a carrier signal S with a first frequency, and in the period in which the polarity of the output voltage Vout and the polarity of the output current Iout are different, a control signal of an element to be caused to perform an on/off operation is generated by being pulse-width modulated using a carrier signal with a second frequency lower than the first fr
    Type: Grant
    Filed: March 18, 2015
    Date of Patent: December 27, 2016
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Qichen Wang, Satoru Fujita
  • Patent number: 9397582
    Abstract: In a power converter, in a period in which the polarities of output voltage and output current of a power converter differ, a pulse train voltage corresponding to a PWM signal is output by a first switching element and a second switching element being turned off, one element of a first switch element and a second switch element being turned on, and the other element being turned on and off based on an inverted signal of a PWM signal pulse width modulated in accordance with an output voltage command.
    Type: Grant
    Filed: March 4, 2015
    Date of Patent: July 19, 2016
    Assignee: FUJI ELECTRIC CO., LTD.
    Inventors: Qichen Wang, Satoru Fujita
  • Publication number: 20160028232
    Abstract: A power conversion device includes an AC power source configured to output an AC voltage, a DC power source configured to output a plurality of DC voltages having different levels, an inverter configured to receive the AC voltage and the plurality of DC voltages and output an output voltage by boosting the AC voltage in a booster mode in accordance with first and second control signals, the booster mode being a mode in which a level of the AC voltage is smaller than a predetermined value, a reactor configured to smooth the output voltage of the inverter, and a control circuit configured to generate the first and second control signals using a first and second carrier signals having different frequencies, respectively, in the booster mode, and selectively output the first or second control signal in accordance with the level of the AC voltage from the AC power source.
    Type: Application
    Filed: October 7, 2015
    Publication date: January 28, 2016
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Qichen WANG, Satoru FUJITA
  • Publication number: 20150194908
    Abstract: When in an operation mode in which an alternating current voltage Vout is output using a positive voltage V1 of a direct current power source 1 input via a switching element Q1, a negative voltage V2 of the direct current power source 1 input via a switching element Q2, and a zero voltage Vz input via a bidirectional switch element BS1 or an alternating current voltage Vs input via a bidirectional switch element BS2, in the period in which the polarity of the output voltage Vout and the polarity of an output current Iout are the same, a control signal of an element to be caused to perform an on/off operation is generated by being pulse-width modulated using a carrier signal S with a first frequency, and in the period in which the polarity of the output voltage Vout and the polarity of the output current Iout are different, a control signal of an element to be caused to perform an on/off operation is generated by being pulse-width modulated using a carrier signal with a second frequency lower than the first fr
    Type: Application
    Filed: March 18, 2015
    Publication date: July 9, 2015
    Applicant: FUJI ELECTRIC CO., LTD.
    Inventors: Qichen WANG, Satoru Fujita