Patents by Inventor Seiji Iyasu

Seiji Iyasu 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: 9762133
    Abstract: A power conversion apparatus for converting AC power supplied from an AC power source to DC power includes an AC-DC conversion circuit connected with the AC power source at an input end thereof for converting the AC power to DC power, a DC-DC conversion circuit connected with an output end of the AC-DC conversion circuit at an input end thereof for converting DC voltage level of the DC power generated by the AC-DC conversion circuit, a smoothing capacitor parallel connected to the output end of the AC-DC conversion circuit and the input end of the DC-DC conversion circuit, a DC link voltage detector for detecting a voltage of the smoothing capacitor as a DC link voltage, and a control unit for controlling operation of the DC-DC conversion circuit. The control unit suppresses an output power of the DC-DC conversion circuit, if the DC link voltage is smaller than a predetermined value.
    Type: Grant
    Filed: January 25, 2017
    Date of Patent: September 12, 2017
    Assignee: DENSO CORPORATION
    Inventors: Yuuichi Handa, Seiji Iyasu, Kimikazu Nakamura
  • Patent number: 9755528
    Abstract: A power conversion apparatus for converting AC power supplied from an AC power source to DC power includes an AC-DC conversion circuit connected with the AC power source at an input end thereof for converting the AC power to DC power, a DC-DC conversion circuit connected with an output end of the AC-DC conversion circuit at an input end thereof for converting DC voltage level of the DC power generated by the AC-DC conversion circuit, a smoothing capacitor parallel connected to the output end of the AC-DC conversion circuit and the input end of the DC-DC conversion circuit, a DC link voltage detector for detecting a voltage of the smoothing capacitor as a DC link voltage, and a control unit for controlling operation of the DC-DC conversion circuit. The control unit suppresses an output power of the DC-DC conversion circuit, if the DC link voltage is smaller than a predetermined value.
    Type: Grant
    Filed: December 27, 2016
    Date of Patent: September 5, 2017
    Assignee: DENSO CORPORATION
    Inventors: Yuuichi Handa, Seiji Iyasu, Kimikazu Nakamura
  • Patent number: 9705397
    Abstract: A power conversion apparatus for converting AC power supplied from an AC power source to DC power includes an AC-DC conversion circuit connected with the AC power source at an input end thereof for converting the AC power to DC power, a DC-DC conversion circuit connected with an output end of the AC-DC conversion circuit at an input end thereof for converting DC voltage level of the DC power generated by the AC-DC conversion circuit, a smoothing capacitor parallel connected to the output end of the AC-DC conversion circuit and the input end of the DC-DC conversion circuit, a DC link voltage detector for detecting a voltage of the smoothing capacitor as a DC link voltage, and a control unit for controlling operation of the DC-DC conversion circuit. The control unit suppresses an output power of the DC-DC conversion circuit, if the DC link voltage is smaller than a predetermined value.
    Type: Grant
    Filed: March 25, 2015
    Date of Patent: July 11, 2017
    Assignee: DENSO CORPORATION
    Inventors: Yuuichi Handa, Seiji Iyasu, Kimikazu Nakamura
  • Patent number: 9692307
    Abstract: Power conversion apparatus converts input voltage and supplies output voltage to the electric load. The apparatus includes a semiconductor switch switches between open and closed states to regulate voltage control current for controlling output voltage, a first voltage detection section detects remote voltage being applied to the electric load as output voltage, a second voltage detection section detects a local voltage being applied to the output terminal as output voltage, a target current calculation section calculates target current which is the voltage control current target value, based on voltage deviation between target voltage which is the output voltage target value and either remote voltage or local voltage, and a switch control section controls the semiconductor switch so voltage control current becomes target current, to regulate output voltage to target voltage.
    Type: Grant
    Filed: September 24, 2015
    Date of Patent: June 27, 2017
    Assignee: Denso Corporation
    Inventors: Seiji Iyasu, Kimikazu Nakamura, Yuuichi Handa
  • Publication number: 20170133942
    Abstract: A power conversion apparatus for converting AC power supplied from an AC power source to DC power includes an AC-DC conversion circuit connected with the AC power source at an input end thereof for converting the AC power to DC power, a DC-DC conversion circuit connected with an output end of the AC-DC conversion circuit at an input end thereof for converting DC voltage level of the DC power generated by the AC-DC conversion circuit, a smoothing capacitor parallel connected to the output end of the AC-DC conversion circuit and the input end of the DC-DC conversion circuit, a DC link voltage detector for detecting a voltage of the smoothing capacitor as a DC link voltage, and a control unit for controlling operation of the DC-DC conversion circuit. The control unit suppresses an output power of the DC-DC conversion circuit, if the DC link voltage is smaller than a predetermined value.
    Type: Application
    Filed: January 25, 2017
    Publication date: May 11, 2017
    Inventors: Yuuichi Handa, Seiji Iyasu, Kimikazu Nakamura
  • Publication number: 20170113567
    Abstract: A control device for a power supply system includes a pre-charge unit, the power supply system having a main electric storage device, a smooth capacitor, a step-up circuit, an open-close switch, a voltage source and a regulation element. The regulation element regulates a current flowing from the smooth capacitor toward the open-close switch. The voltage source is connected to a connection portion between the open-close switch and the step-up circuit, and outputs an output voltage higher than a voltage of the main electric storage device before the open-close switch is shifted from a disconnection state to a connection state. The pre-charge unit executes a pre-charge of the smooth capacitor by supplying electric power from the voltage source to the smooth capacitor before the open-close switch is shifted from the disconnection state to the connection state.
    Type: Application
    Filed: October 13, 2016
    Publication date: April 27, 2017
    Applicants: DENSO CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Kaoru KOKETSU, Yuichi HANDA, Seiji IYASU, Takashi NOZAWA
  • Publication number: 20170110972
    Abstract: A power conversion apparatus for converting AC power supplied from an AC power source to DC power includes an AC-DC conversion circuit connected with the AC power source at an input end thereof for converting the AC power to DC power, a DC-DC conversion circuit connected with an output end of the AC-DC conversion circuit at an input end thereof for converting DC voltage level of the DC power generated by the AC-DC conversion circuit, a smoothing capacitor parallel connected to the output end of the AC-DC conversion circuit and the input end of the DC-DC conversion circuit, a DC link voltage detector for detecting a voltage of the smoothing capacitor as a DC link voltage, and a control unit for controlling operation of the DC-DC conversion circuit. The control unit suppresses an output power of the DC-DC conversion circuit, if the DC link voltage is smaller than a predetermined value.
    Type: Application
    Filed: December 27, 2016
    Publication date: April 20, 2017
    Inventors: Yuuichi HANDA, Seiji IYASU, Kimikazu NAKAMURA
  • Publication number: 20170085181
    Abstract: A power conversion apparatus supplies power from a DC power supply to a capacitive load by a current input push-pull DCDC converter provided with switching elements Q1 and Q2. When a capacitive load voltage is not larger than a second predetermined value, a first mode is used which turns ON one of the switching elements Q1 and Q2 alternated with turning OFF both. When the capacitive load voltage is larger than the second predetermined value but not larger than a first predetermined value, a second mode is used which turns ON both of the switching elements Q1 and Q2, then turns ON one of them, then turns OFF both, sequentially. When the capacitive load voltage is larger than the first predetermined value, a third mode is used, turning ON both of the switching elements Q1 and Q2 alternated with turning ON one of them.
    Type: Application
    Filed: September 17, 2015
    Publication date: March 23, 2017
    Inventors: Kenji TOMITA, Kimikazu NAKAMURA, Shinya GOTO, Katsutoyo MISAWA, Yuuichi HANDA, Seiji IYASU
  • Patent number: 9602008
    Abstract: A power conversion apparatus supplies power from a DC power supply to a capacitive load by a current input push-pull DCDC converter provided with switching elements Q1 and Q2. When a capacitive load voltage is not larger than a second predetermined value, a first mode is used which turns ON one of the switching elements Q1 and Q2 alternated with turning OFF both. When the capacitive load voltage is larger than the second predetermined value but not larger than a first predetermined value, a second mode is used which turns ON both of the switching elements Q1 and Q2, then turns ON one of them, then turns OFF both, sequentially. When the capacitive load voltage is larger than the first predetermined value, a third mode is used, turning ON both of the switching elements Q1 and Q2 alternated with turning ON one of them.
    Type: Grant
    Filed: September 17, 2015
    Date of Patent: March 21, 2017
    Assignee: DENSO CORPORATION
    Inventors: Kenji Tomita, Kimikazu Nakamura, Shinya Goto, Katsutoyo Misawa, Yuuichi Handa, Seiji Iyasu
  • Publication number: 20170033696
    Abstract: A power conversion apparatus includes a power conversion circuit, a choke coil, an auxiliary coil, and a rectifier element. The choke coil is disposed between the power conversion circuit and an input side direct current power source. The auxiliary coil is magnetically coupled to the choke coil and is connected in parallel with an output side circuit. The auxiliary coil is wound in a direction so that an excitation current flows from a negative electrode to a positive electrode of the output side circuit when an excitation current flows from a positive electrode to a negative electrode of the direct current power source through the choke coil. The rectifier element is series connection with the auxiliary coil, and cuts off power supply from the direct current power source to the output side circuit through the auxiliary coil and power supply from the output side circuit to the input side.
    Type: Application
    Filed: July 28, 2016
    Publication date: February 2, 2017
    Applicant: DENSO CORPORATION
    Inventors: Yuuichi HANDA, Seiji IYASU, Kimikazu NAKAMURA
  • Patent number: 9391472
    Abstract: A battery charger of a battery charging apparatus is disposed on an exterior case of an engine in such a manner that a generated heat is transferred therebetween. An ECU drives a cooling system when an engine temperature and temperature of the battery charger satisfy a predetermined cooling temperature condition. A cooling capacity for cooling the battery charger is improved by establishing a heat radiation passage to radiate a heat from the battery charger efficiently.
    Type: Grant
    Filed: September 21, 2012
    Date of Patent: July 12, 2016
    Assignees: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Seiji Iyasu, Shinji Andou, Sadahisa Onimaru, Kazuyoshi Obayashi
  • Patent number: 9350179
    Abstract: A charging device for a battery of a vehicle includes an insulation resistance detecting circuit, a charging circuit, a leak current detecting circuit and a decoupling circuit. The insulation resistance detecting circuit includes a coupling capacitor, and is disposed between the battery and a vehicle body for detecting an insulation resistance between the battery and the vehicle body. The charging circuit converts an alternating current supplied from an alternating current source into a direct current and charges the battery in a state without insulting the input terminal and the output terminal and in a state where the vehicle body is coupled to an earth. The leak current detecting circuit detects a leak current between the charging circuit and the earth. The decoupling circuit decouples the insulation resistance detecting circuit from one of the battery and the vehicle body during a charging of the battery.
    Type: Grant
    Filed: May 21, 2013
    Date of Patent: May 24, 2016
    Assignee: DENSO CORPORATION
    Inventors: Shinji Ando, Seiji Iyasu, Sadahisa Onimaru, Kazuyoshi Obayashi
  • Publication number: 20160094134
    Abstract: Power conversion apparatus converts input voltage and supplies output voltage to the electric load. The apparatus includes a semiconductor switch switches between open and closed states to regulate voltage control current for controlling output voltage, a first voltage detection section detects remote voltage being applied to the electric load as output voltage, a second voltage detection section detects a local voltage being applied to the output terminal as output voltage, a target current calculation section calculates target current which is the voltage control current target value, based on voltage deviation between target voltage which is the output voltage target value and either remote voltage or local voltage, and a switch control section controls the semiconductor switch so voltage control current becomes target current, to regulate output voltage to target voltage.
    Type: Application
    Filed: September 24, 2015
    Publication date: March 31, 2016
    Inventors: Seiji IYASU, Kimikazu NAKAMURA, Yuuichi HANDA
  • Patent number: 9236760
    Abstract: An AC-DC converter converts an alternating-current voltage, supplied from an external power supply, to a direct-current voltage higher than a peak voltage of the alternating-current voltage, and outputs the direct-current voltage to a first power supply line. In a normal control mode, a DC-DC converter steps down a voltage of the power supply line through on/off control over a switching element to charge a main battery. On the other hand, in an upper arm ON control mode, the DC-DC converter charge the main battery while the switching element is kept in an on state. On the basis of a state of external charging, a control device applies the upper arm ON control mode when a condition that upper arm ON control is applicable is satisfied, and applies the normal control mode when the condition is not satisfied.
    Type: Grant
    Filed: July 4, 2011
    Date of Patent: January 12, 2016
    Assignees: TOYOTA JIDOSHA KABUSHIKI KAISHA, NIPPON SOKEN, INC.
    Inventors: Seiji Iyasu, Toru Wakimoto, Kenji Itagaki, Yoshinobu Sugiyama
  • Patent number: 9184674
    Abstract: A power conversion apparatus includes: a bridge circuit between AC and DC ends; a converter circuit between the bridge circuit and the DC end; and a control device for the converter circuit. The converter circuit includes: first and second switches in series between terminals of the bridge circuit; third and fourth switches in series between terminals of the DC end; and a reactor between an intermediate point of the first and second switches and an intermediate point of the third and fourth switches. The control device includes: a first controller defining a part of a cycle of an AC voltage as a stop period and stopping switching the first and second switches during the stop period; and a second controller performing voltage/power factor correction controls over an entire cycle by switching the third and/or fourth switches.
    Type: Grant
    Filed: May 3, 2013
    Date of Patent: November 10, 2015
    Assignee: DENSO CORPORATION
    Inventors: Seiji Iyasu, Shinji Ando, Sadahisa Onimaru, Kazuyoshi Obayashi
  • Publication number: 20150280591
    Abstract: A power conversion apparatus for converting AC power supplied from an AC power source to DC power includes an AC-DC conversion circuit connected with the AC power source at an input end thereof for converting the AC power to DC power, a DC-DC conversion circuit connected with an output end of the AC-DC conversion circuit at an input end thereof for converting DC voltage level of the DC power generated by the AC-DC conversion circuit, a smoothing capacitor parallel connected to the output end of the AC-DC conversion circuit and the input end of the DC-DC conversion circuit, a DC link voltage detector for detecting a voltage of the smoothing capacitor as a DC link voltage, and a control unit for controlling operation of the DC-DC conversion circuit.
    Type: Application
    Filed: March 25, 2015
    Publication date: October 1, 2015
    Inventors: Yuuichi HANDA, Seiji IYASU, Kimikazu NAKAMURA
  • Patent number: 9067477
    Abstract: A power supply device includes a refrigeration cycle having a compressor, a motor, an inverter-integrated charger, a heat exchanger unit, and a controller having a determining unit. The inverter-integrated charger selectively controls operation of the motor using electrical power of a battery and charge of the battery with external power. The heat exchanger unit cools a cooling-necessary part of the inverter-integrated charger using refrigerant in the refrigeration cycle. When the vehicle is stopped and the battery is charged with the external power, the controller makes the inverter-integrated charger serve as: a charger to perform the charge of the battery; or an inverter to control the operation of the motor, thereby driving the compressor, upon determination that the cooling-necessary part needs to be cooled by the determining unit.
    Type: Grant
    Filed: April 17, 2012
    Date of Patent: June 30, 2015
    Assignees: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Sadahisa Onimaru, Shinji Andou, Seiji Iyasu, Kazuyoshi Obayashi, Akira Sakamoto, Shigeru Kawano
  • Publication number: 20130308230
    Abstract: A charging device for a battery of a vehicle includes an insulation resistance detecting circuit, a charging circuit, a leak current detecting circuit and a decoupling circuit. The insulation resistance detecting circuit includes a coupling capacitor, and is disposed between the battery and a vehicle body for detecting an insulation resistance between the battery and the vehicle body. The charging circuit converts an alternating current supplied from an alternating current source into a direct current and charges the battery in a state without insulting the input terminal and the output terminal and in a state where the vehicle body is coupled to an earth. The leak current detecting circuit detects a leak current between the charging circuit and the earth. The decoupling circuit decouples the insulation resistance detecting circuit from one of the battery and the vehicle body during a charging of the battery.
    Type: Application
    Filed: May 21, 2013
    Publication date: November 21, 2013
    Applicant: DENSO CORPORATION
    Inventors: Shinji ANDO, Seiji IYASU, Sadahisa ONIMARU, Kazuyoshi OBAYASHI
  • Publication number: 20130301323
    Abstract: A power conversion apparatus includes: a bridge circuit between AC and DC ends; a converter circuit between the bridge circuit and the DC end; and a control device for the converter circuit. The converter circuit includes: first and second switches in series between terminals of the bridge circuit; third and fourth switches in series between terminals of the DC end; and a reactor between an intermediate point of the first and second switches and an intermediate point of the third and fourth switches. The control device includes: a first controller defining a part of a cycle of an AC voltage as a stop period and stopping switching the first and second switches during the stop period; and a second controller performing voltage/power factor correction controls over an entire cycle by switching the third and/or fourth switches.
    Type: Application
    Filed: May 3, 2013
    Publication date: November 14, 2013
    Applicant: DENSO CORPORATION
    Inventors: Seiji Iyasu, Shinji Ando, Sadahisa Onimaru, Kazuyoshi Obayashi
  • Publication number: 20130093394
    Abstract: An AC-DC converter converts an alternating-current voltage, supplied from an external power supply, to a direct-current voltage higher than a peak voltage of the alternating-current voltage, and outputs the direct-current voltage to a first power supply line. In a normal control mode, a DC-DC converter steps down a voltage of the power supply line through on/off control over a switching element to charge a main battery. On the other hand, in an upper arm ON control mode, the DC-DC converter charge the main battery while the switching element is kept in an on state. On the basis of a state of external charging, a control device applies the upper arm ON control mode when a condition that upper arm ON control is applicable is satisfied, and applies the normal control mode when the condition is not satisfied.
    Type: Application
    Filed: July 4, 2011
    Publication date: April 18, 2013
    Applicants: NIPPON SOKEN, INC., TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Seiji Iyasu, Toru Wakimoto, Kenji Itagaki, Yoshinobu Sugiyama