Patents by Inventor Junichi Itoh

Junichi Itoh 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: 9369055
    Abstract: A power converter is provided for direct conversion of multi-phase AC power to AC power. The power converter includes a conversion circuit, a plurality of input lines and a plurality of capacitors. The conversion circuit has first and second switching elements that are configured to be connected to the phases of the multi-phase AC power for bidirectional switching of energizing current. The input lines are connected to the conversion circuit. The capacitors are connected to the conversion circuit. The first and second switching elements are arranged such that paired input terminals line up in a row with the paired input terminals to an outside, and paired output terminals to an inside. The input lines extend in a direction in which the paired input terminals line up, and extend from one of the input terminals to another of the input terminals.
    Type: Grant
    Filed: September 28, 2012
    Date of Patent: June 14, 2016
    Assignees: Nissan Motor Co., Ltd., NATIONAL UNIVERSITY CORPORATION NAGAOKA UNIVERSITY OF TECHNOLOGY
    Inventors: Hironori Koyano, Takamasa Nakamura, Kouji Yamamoto, Junichi Itoh, Yoshiya Ohnuma
  • Patent number: 9203325
    Abstract: An electric power conversion device comprises a conversion circuit having bi-directionally switchable plural pairs of switching elements connected to respective phases and converting an inputted AC power into an AC electric power. A first switching time is calculated using detected voltages detected by voltage sensors and an output command value. A second switching time is calculated using a carrier and the first switching time. A control signal generating section generates control signals to switch on and off of the switching elements using the first switching time and second switching time. In a case where a state is transited from the first switching time to the second switching time, a controller turns off one of on a state switching elements of either one of an upper arm circuit or a lower arm circuit and maintains on state of the other of the on state switching elements of the other arm circuit.
    Type: Grant
    Filed: September 6, 2012
    Date of Patent: December 1, 2015
    Assignees: NISSAN MOTOR CO., LTD., NAGAOKA UNIVERSITY OF TECHNOLOGY
    Inventors: Masao Saito, Takamasa Nakamura, Kouji Yamamoto, Junichi Itoh, Yoshiya Ohnuma
  • Patent number: 9197137
    Abstract: An electric power conversion device comprises a conversion circuit having bi-directionally switchable plural pairs of switching elements connected to respective phases and converting an inputted AC power into an AC electric power. A first switching time is calculated using detected voltages detected by voltage sensors and an output command value. A second switching time is calculated using a carrier and the calculated first switching time. The second switching time is such that, in one period of the alternating current electric power outputted from the conversion circuit, the second switching time included in a first half period of the one period is equal to the second switching time included in a second half period of the one period.
    Type: Grant
    Filed: September 6, 2012
    Date of Patent: November 24, 2015
    Assignees: NISSAN MOTOR CO., LTD., NAGAOKA UNIVERSITY OF TECHNOLOGY
    Inventors: Masao Saito, Takamasa Nakamura, Kouji Yamamoto, Junichi Itoh, Yoshiya Ohnuma
  • Patent number: 9190922
    Abstract: An electric power conversion device comprises a conversion circuit having bi-directionally switchable plural pairs of switching elements connected to respective phases and converting an inputted AC power into an AC electric power. A first switching time is calculated using detected voltages detected by voltage sensors and an output command value. A second switching time is calculated in a form of a time which is a subtraction of the first switching time from a half period of a carrier and, using this time, control signals to switch on and off of the switching elements are generated.
    Type: Grant
    Filed: September 6, 2012
    Date of Patent: November 17, 2015
    Assignees: NISSAN MOTOR CO., LTD., NAGAOKA UNIVERSITY OF TECHNOLOGY
    Inventors: Masao Saito, Takamasa Nakamura, Kouji Yamamoto, Junichi Itoh, Yoshiya Ohnuma
  • Patent number: 9190925
    Abstract: The AC converter converts a single-phase input AC voltage with a frequency f0 into a three-phase output AC voltage with a frequency f1 that is lower than f0. The AC converter includes a switching section with multiple switching elements and a switching control section that controls the conduction states of the respective switching elements. The switching control section supplies pulses that have been subjected to a pulse density modulation based on space vector modulation to the switching section, thereby getting the conversion into a three-phase output AC voltage done.
    Type: Grant
    Filed: November 15, 2012
    Date of Patent: November 17, 2015
    Assignee: Panasonic Corporation
    Inventors: Hiroshi Yamamoto, Junichi Itoh
  • Patent number: 9148072
    Abstract: In an inverter apparatus, an output voltage of an active filter circuit that steps up and smoothes a DC voltage is converted into an AC voltage by an inverter circuit. The active filter circuit includes a capacitor and a rectifier device connected between an input node and an output node. An inductor, one end of which is connected to the input node and the other end of which is connected the output node through the rectifier device, and a switch device connected between the other end and a low-potential-side line, and a first control circuit for the switch device are provided. The inductor stores energy while the switch device is on and releases the energy while the switch device is off. The rectifier device conducts such that the stored energy of the inductor is released.
    Type: Grant
    Filed: September 2, 2014
    Date of Patent: September 29, 2015
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Koichi Ueki, Junichi Itoh, Yoshiya Ohnuma
  • Patent number: 9013906
    Abstract: In a power-system-interconnected inverter device, PI control circuits obtain voltage correction values in directions reducing the current errors on the basis of current errors serving as differences between target current values and detection values. Multiplexers provide modulation circuits with voltage target values corrected by the voltage correction values being added to voltage detection values. The modulation circuits provide gate signals for switch elements in multilevel circuits. In addition, a sign circuit provides gate signals for switch elements in a bridge clamping circuit.
    Type: Grant
    Filed: February 22, 2013
    Date of Patent: April 21, 2015
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Junichi Itoh, Yuichi Noge
  • Patent number: 9001544
    Abstract: In an inverter device, a first three-level circuit includes first to fourth preceding-stage switch elements connected in series between a first input end and a ground and a first charging and discharging capacitor. A second three-level circuit includes fifth to eighth preceding-stage switch elements connected in series between a second input end and the ground and a second charging and discharging capacitor. The first and second two three-level circuits define a five-level circuit that is subjected to switching with the carrier frequency of PWM modulation. The output polarity of a subsequent-stage bridge clamping circuit is inverted between the anterior half cycle and the posterior half cycle of a power supply frequency.
    Type: Grant
    Filed: February 22, 2013
    Date of Patent: April 7, 2015
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Junichi Itoh, Yuichi Noge
  • Publication number: 20140369090
    Abstract: In an inverter apparatus, an output voltage of an active filter circuit that steps up and smoothes a DC voltage is converted into an AC voltage by an inverter circuit. The active filter circuit includes a capacitor and a rectifier device connected between an input node and an output node. An inductor, one end of which is connected to the input node and the other end of which is connected the output node through the rectifier device, and a switch device connected between the other end and a low-potential-side line, and a first control circuit for the switch device are provided. The inductor stores energy while the switch device is on and releases the energy while the switch device is off. The rectifier device conducts such that the stored energy of the inductor is released.
    Type: Application
    Filed: September 2, 2014
    Publication date: December 18, 2014
    Inventors: Koichi UEKI, Junichi ITOH, Yoshiya OHNUMA
  • Publication number: 20140247636
    Abstract: A power converter is provided for direct conversion of multi-phase AC power to AC power. The power converter includes a conversion circuit and a plurality of output lines. The conversion circuit has first and second switching elements that are configured to be connected to phases of the multi-phase AC power for bidirectional switching of energizing current. The output lines are connected to the conversion circuit. The first and second switching elements have output terminals. The output terminals of the first and second switching elements are arranged in first and second rows. The output terminals of the first and second switching elements face each other. The first output lines include two first output lines including first and second widely shaped bus bars connected to the output terminals of the first and second switching elements, respectively. The first output lines extending out in one direction, and line up in an upright direction.
    Type: Application
    Filed: September 28, 2012
    Publication date: September 4, 2014
    Inventors: Hironori Koyano, Takamasa Nakamura, Kouji Yamamoto, Junichi Itoh, Yoshiya Ohnuma
  • Publication number: 20140247635
    Abstract: A power converter is provided for direct conversion of multi-phase AC power to AC power. The power converter includes a conversion circuit, a plurality of input lines and a plurality of capacitors. The conversion circuit has first and second switching elements that are configured to be connected to the phases of the multi-phase AC power for bidirectional switching of energizing current. The input lines are connected to the conversion circuit. The capacitors are connected to the conversion circuit. The first and second switching elements are arranged such that paired input terminals line up in a row with the paired input terminals to an outside, and paired output terminals to an inside. The input lines extend in a direction in which the paired input terminals line up, and extend from one of the input terminals to another of the input terminals.
    Type: Application
    Filed: September 28, 2012
    Publication date: September 4, 2014
    Applicant: National University Corporation Nagaoka University of Technology
    Inventors: Hironori Koyano, Takamasa Nakamura, Kouji Yamamoto, Junichi Itoh, Yoshiya Ohnuma
  • Publication number: 20140233280
    Abstract: An electric power conversion device comprises a conversion circuit having bi-directionally switchable plural pairs of switching elements connected to respective phases and converting an inputted AC power into an AC electric power. A first switching time is calculated using detected voltages detected by voltage sensors and an output command value. A second switching time is calculated using a carrier and the first switching time. A control signal generating section generates control signals to switch on and off of the switching elements using the first switching time and second switching time. In a case where a state is transited from the first switching time to the second switching time, a controller tarns off one of on state switching elements of either one of an upper arm circuit or a lower arm circuit and maintains on state of the other of the on state switching elements of the other arm circuit.
    Type: Application
    Filed: September 6, 2012
    Publication date: August 21, 2014
    Inventors: Masao Saito, Takamasa Nakamura, Kouji Yamamoto, Junichi Itoh, Yoshiya Ohnuma
  • Publication number: 20140226382
    Abstract: An electric power conversion device comprises a conversion circuit having bi-directionally switchable plural pairs of switching elements connected to respective phases and converting an inputted AC power into an AC electric power. A first switching time is calculated using detected voltages detected by voltage sensors and an output command value. A second switching time is calculated using a carrier and the calculated first switching time. The second switching time is such that, in one period of the alternating current electric power outputted from the conversion circuit, the second switching time included in a first half period of the one period is equal to the second switching time included in a second half period of the one period.
    Type: Application
    Filed: September 6, 2012
    Publication date: August 14, 2014
    Inventors: Masao Saito, Takamasa Nakamura, Kouji Yamamoto, Junichi Itoh, Yoshiya Ohnuma
  • Publication number: 20140226386
    Abstract: An electric power conversion device comprises a conversion circuit having bi-directionally switchable plural pairs of switching elements connected to respective phases and converting an inputted AC power into an AC electric power. A first switching time is calculated using detected voltages detected by voltage sensors and an output command value. A second switching time is calculated in a form of a time which is a subtraction of the first switching time from a half period of a carrier and, using this time, control signals to switch on and off of the switching elements are generated.
    Type: Application
    Filed: September 6, 2012
    Publication date: August 14, 2014
    Inventors: Masao Saito, Takamasa Nakamura, Kouji Yamamoto, Junichi Itoh, Yoshiya Ohnuma
  • Publication number: 20140192578
    Abstract: Provided is a power converter 3 that directly converts polyphase AC power to AC power. A converter circuit has a plurality of first switching elements 311, 313 and 315 that are connected to each phase R, S or T of the polyphase AC power to enable switching for turning on current-carrying bidirectionally, and a plurality of second switching elements 312, 314 and 316 that are connected to each phase to enable switching for turning on current-carrying bidirectionally. The converter circuit comprises input lines R, S and T connected to each input terminal, and output lines P and N connected to each output terminal. Parts of wiring 347 and 348 of protection circuits 32 are located between output lines P and N. The wiring distance between each protection circuit 32 and the corresponding switching element can be shortened.
    Type: Application
    Filed: May 7, 2012
    Publication date: July 10, 2014
    Applicants: Nagaoka University of Technology, NISSAN MOTOR CO., LTD
    Inventors: Hironori Koyano, Takamasa Nakamura, Masao Saito, Kouji Yamamoto, Tsutomu Matsukawa, Manabu Koshijo, Junichi Itoh, Yoshiya Ohnuma
  • Publication number: 20140185326
    Abstract: There is disclosed a power conversion apparatus 3 for converting polyphase ac power directly to ac power. A conversion circuit includes a plurality of first switching devices 311, 313, 315 and a plurality of second switching devices 312, 314, 316 connected, respectively, with the phases R, S, T of the polyphase ac power, and configured to enable electrical switching operation in both directions. Output lines 331, 332 formed by a pair of busbars are connected with the conversion circuit. The first switching devices and the second switching devices are so arranged that output terminals are arranged in a row. The output lines 331, 332 are connected with the output terminals and drawn out rectilinearly in one direction.
    Type: Application
    Filed: May 7, 2012
    Publication date: July 3, 2014
    Inventors: Hironori Koyano, Takamasa Nakamura, Masao Saito, Kouji Yamamoto, Tsutomu Matsukawa, Manabu Koshijo, Junichi Itoh, Yoshiya Ohnuma
  • Publication number: 20140126263
    Abstract: There is disclosed a power conversion apparatus 3 for converting polyphase ac power directly to ac power. A conversion circuit includes first switching devices 311, 313, 315 and second switching devices 312, 314, 316 connected, respectively, with the phases R, S, T of the polyphase ac power, and configured to enable electrical switching operation in both directions. There are provided input lines R, S, T connected with input terminals of the switching devices and output lines P, N connected with output terminals of the switching devices. The output terminals of the first switching devices and the output terminals of the second switching devices are, respectively, arranged in a row. The first switching devices and second switching devices are arranged side by side with respect to a direction of the rows. The output lines are disposed below the input lines in an up and down direction.
    Type: Application
    Filed: May 7, 2012
    Publication date: May 8, 2014
    Inventors: Hironori Koyano, Takamasa Nakamura, Masao Saito, Kouji Yamamoto, Tsutomu Matsukawa, Manabu Koshijo, Junichi Itoh, Yoshiya Ohnuma
  • Publication number: 20140104913
    Abstract: Provided is a power converter 3 that directly converts polyphase AC power to AC power. A converter circuit has a plurality of switching elements 311, 313, 315, 312, 314 and 316 which are connected to each phase R, S or T of the polyphase AC power to enable switching for turning on current-carrying bidirectionally. At least three condensers 821 to 826 are provided between phases of the converter circuit. The three condensers are respectively placed at apexes of a triangle on a plane that is in parallel with a part-mounting surface on which the switching elements are actually mounted. The wiring distance between the condensers and the switching elements can be shortened.
    Type: Application
    Filed: May 7, 2012
    Publication date: April 17, 2014
    Inventors: Hironori Koyano, Takamasa Nakamura, Masao Saito, Kouji Yamamoto, Tsutomu Matsukawa, Manabu Koshijo, Junichi Itoh, Yoshiya Ohnuma
  • Publication number: 20140085956
    Abstract: A power conversion apparatus is for converting polyphase ac power directly to ac power. A conversion circuit includes a plurality of first switching devices 311, 313, 315 and a plurality of second switching devices 312, 314, 316 connected, respectively, with the phases R, S, T of the polyphase ac power, and configured to enable electrical switching operation in both directions. There are provided a plurality of condensers 821˜826 connected with the conversion circuit. At least one of the condensers is provided, for each of the first switching devices and the second switching devices, between two of the phases of the polyphase ac power. It is possible to reduce a wiring distance between the condenser and the switching devices.
    Type: Application
    Filed: May 7, 2012
    Publication date: March 27, 2014
    Inventors: Hironori Koyano, Takamasa Nakamura, Masao Saito, Kouji Yamamoto, Tsutomu Matsukawa, Manabu Koshijo, Junichi Itoh, Yoshiya Ohnuma
  • Publication number: 20140085950
    Abstract: Provided is a power converter 3 that directly converts polyphase AC power to AC power. A converter circuit has a plurality of first switching elements 311, 313 and 315 and a plurality of second switching elements 312, 314 and 316, both of which are connected to each phase R, S or T of the polyphase AC power to enable switching for turning on current-carrying bidirectionally. Condensers 821 to 826 are provided between phases. Input terminals of the first switching elements and those of the second switching elements are arranged to form respective lines. Some of the plurality of condensers 821 and 822 are arranged to be angled relative to the arrangement direction of the terminals. The wiring distance between the condensers and the switching elements can be shortened.
    Type: Application
    Filed: May 7, 2012
    Publication date: March 27, 2014
    Applicants: Nagaoka University of Technology, NISSAN MOTOR CO., LTD
    Inventors: Hironori Koyano, Takamasa Nakamura, Masao Saito, Kouji Yamamoto, Tsutomu Matsukawa, Manabu Koshijo, Junichi Itoh, Yoshiya Ohnuma