Patents by Inventor Sho Kato

Sho Kato 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: 9246428
    Abstract: A vector control device includes a vector control unit computing an output voltage output from the electric power converter according to vector control based on torque command and flux command and generating a PWM signal for controlling the electric power converter based on the output voltage, a first flux-command generation unit generating a flux command for asynchronous PWM mode, and a second flux-command generation unit generating a flux command for synchronous PWM mode. When an output frequency of the electric power converter is lower than a predetermined value, a flux command generated by the first flux-command generation unit is input to the vector control unit, and when the output frequency of the electric power converter is equal to or higher than a predetermined value, a flux command generated by the second flux-command generation unit is input to the vector control unit.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: January 26, 2016
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Ryo Yokozutsumi, Yuruki Okada, Hisanori Yamasaki, Sho Kato
  • Publication number: 20150357938
    Abstract: A power converter fixes, in one cycle of an alternating-current voltage output command, a gate pulse signal to always output a direct-current input positive side terminal voltage value of an inverter circuit in a period X1 centering on a phase angle ?1 for higher potential, fixes a gate pulse signal to always output a direct-current input negative side terminal voltage value of the inverter circuit in a period X2 centering on a phase angle ?2 for lower potential, and outputs a gate pulse signal in which a ratio of a period Y1, which is obtained by excluding the periods X1 and X2 from a period between the phase angle ?1 and the phase angle ?2, and the first period X1, and a ratio of a period Y2, which is obtained by excluding the periods X1 and X2 from a period between the phase angle ?2 and a phase angle ?1+360 [deg].
    Type: Application
    Filed: September 2, 2013
    Publication date: December 10, 2015
    Applicant: Mitsubishi Electric Corporation
    Inventors: Hisanori YAMASAKI, Sho KATO, Yuruki OKADA, Ryo YOKOZUTSUMI
  • Publication number: 20150236609
    Abstract: A control section for controlling a 3-level power conversion circuit. The control section calculates ON voltage error based on time ratios of three potentials in a predetermined certain period and a current value from a current detection section for detecting current outputted from the 3-level power conversion circuit, corrects a voltage command value based on a voltage correction amount for correcting the ON voltage error, and performs ON/OFF control for semiconductor switching elements of the 3-level power conversion circuit based on the corrected voltage command value.
    Type: Application
    Filed: August 22, 2013
    Publication date: August 20, 2015
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Sho Kato, Hisanori Yamasaki, Yuruki Okada, Yoshinori Yamashita
  • Publication number: 20150194918
    Abstract: A resistance calculation activator determines whether or not an electric car is stopped on the basis of a drive command signal and an external signal, and activates a resistance calculator if a powering command is input as the drive command when it is determined that the electric car is stopped. The activated resistance calculator computes, within a resistance calculation period, a resistance value of an AC motor that produces driving force for the electric car, on the basis of a d-axis voltage command value and a d-axis current value supplied to the AC motor.
    Type: Application
    Filed: August 9, 2012
    Publication date: July 9, 2015
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yoshinori Yamashita, Sho Kato, Hisanori Yamasaki, Ryo Yokozutsumi, Yuruki Okada
  • Publication number: 20150053264
    Abstract: An object is to increase conversion efficiency of a photoelectric conversion device without increase in the manufacturing steps. The photoelectric conversion device includes a first semiconductor layer formed using a single crystal semiconductor having one conductivity type which is formed over a supporting substrate, a buffer layer including a single crystal region and an amorphous region, a second semiconductor layer which includes a single crystal region and an amorphous region and is provided over the butler layer, and a third semiconductor layer having a conductivity type opposite to the one conductivity type, which is provided over the second semiconductor layer. A proportion of the single crystal region is higher than that of the amorphous region on the first semiconductor layer side in the second semiconductor layer, and the proportion of the amorphous region is higher than that of the single crystal region on the third semiconductor layer side.
    Type: Application
    Filed: October 15, 2014
    Publication date: February 26, 2015
    Inventors: Sho KATO, Yoshikazu HIURA, Akihisa SHIMOMURA, Takashi OHTSUKI, Satoshi TORIUMI, Yasuyuki ARAI
  • Patent number: 8872021
    Abstract: An object is to increase conversion efficiency of a photoelectric conversion device without increase in the manufacturing steps. The photoelectric conversion device includes a first semiconductor layer formed using a single crystal semiconductor having one conductivity type which is formed over a supporting substrate, a buffer layer including a single crystal region and an amorphous region, a second semiconductor layer which includes a single crystal region and an amorphous region and is provided over the buffer layer, and a third semiconductor layer having a conductivity type opposite to the one conductivity type, which is provided over the second semiconductor layer. A proportion of the single crystal region is higher than that of the amorphous region on the first semiconductor layer side in the second semiconductor layer, and the proportion of the amorphous region is higher than that of the single crystal region on the third semiconductor layer side.
    Type: Grant
    Filed: September 23, 2009
    Date of Patent: October 28, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Sho Kato, Yoshikazu Hiura, Akihisa Shimomura, Takashi Ohtsuki, Satoshi Toriumi, Yasuyuki Arai
  • Patent number: 8846496
    Abstract: To provide a method of obtaining a single crystal semiconductor film by a method that is simple and low-cost. A single crystal semiconductor film 11 having compression stress is formed over a surface of a single crystal semiconductor substrate 10 by a vapor phase epitaxial growth method, a film having tensile stress (for example, a thermo-setting resin film 12) is formed over a surface of the single crystal semiconductor film 11, and the single crystal semiconductor substrate 10 and the single crystal semiconductor film 11 are separated from each other by a separation step in which force is applied to the single crystal semiconductor film 11, thereby obtaining a single crystal semiconductor film. Note that as the thermo-setting resin film 12, an epoxy resin film can be used, for example.
    Type: Grant
    Filed: April 22, 2011
    Date of Patent: September 30, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Sho Kato, Kazutaka Kuriki
  • Patent number: 8847528
    Abstract: A control apparatus for an AC rotary machine includes a control circuit, a power converter, a current detector, and a voltage detector. The control circuit includes: an activation current instruction unit which generates a current instruction for activation; and a start phase setting unit which sets an initial rotation phase for activation control, based on the rotation direction of the AC rotary machine just after activation and on the polarity of current detected by the current detector just after activation. Thus, the current amplitude and torque shock just after activation control is started can be reduced, and assured and stable reactivation is allowed without causing the protection operation.
    Type: Grant
    Filed: July 23, 2010
    Date of Patent: September 30, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Sho Kato, Hisanori Yamasaki, Masaki Kono, Keita Hatanaka
  • Patent number: 8836253
    Abstract: A control apparatus for an AC rotary machine includes: a current detection section detecting current from a power converter to the AC rotary machine; and a control section generating a three-phase AC voltage instruction to the power converter, based on current detected by the current detection section and a torque instruction. The control section includes: an observer calculating a magnetic flux estimated value of the AC rotary machine, based on detected current and the voltage instruction; a current instruction calculation unit calculating current instruction values on rotational two axes, based on the torque instruction and the magnetic flux estimated value from the observer; and a voltage instruction calculation unit calculating the voltage instruction, based on the current instruction values from the current instruction calculation unit and the magnetic flux estimated value from the observer.
    Type: Grant
    Filed: March 25, 2011
    Date of Patent: September 16, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Sho Kato, Hisanori Yamasaki, Keita Hatanaka, Hidetoshi Kitanaka, Yoshinori Yamashita
  • Patent number: 8816622
    Abstract: A control apparatus for an AC rotating machine that can reliably and stably start up an AC rotating machine, particularly a synchronous motor using a permanent magnet, in position-sensorless vector control thereof, includes: a steady speed calculator that calculates, during steady state control of the AC rotating machine, a rotation angular frequency of the AC rotating machine based on an AC current and voltage commands; and a start-up speed calculator that calculates, during start-up control within a predetermined period after the AC rotating machine has been started up, the rotation angular frequency of the AC rotating machine based on the AC current and the voltage commands. The control apparatus corrects during the start-up control current commands so that the AC voltage amplitude of the voltage commands will be a constant value not more than the maximum output voltage of a power converter.
    Type: Grant
    Filed: July 26, 2011
    Date of Patent: August 26, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Sho Kato, Hisanori Yamasaki, Keita Hatanaka, Hidetoshi Kitanaka, Yoshinori Yamashita
  • Publication number: 20140232307
    Abstract: A vector control device includes a vector control unit computing an output voltage output from the electric power converter according to vector control based on torque command and flux command and generating a PWM signal for controlling the electric power converter based on the output voltage, a first flux-command generation unit generating a flux command for asynchronous PWM mode, and a second flux-command generation unit generating a flux command for synchronous PWM mode. When an output frequency of the electric power converter is lower than a predetermined value, a flux command generated by the first flux-command generation unit is input to the vector control unit, and when the output frequency of the electric power converter is equal to or higher than a predetermined value, a flux command generated by the second flux-command generation unit is input to the vector control unit.
    Type: Application
    Filed: September 30, 2011
    Publication date: August 21, 2014
    Applicant: Mitsubishi Electric Corporation
    Inventors: Ryo Yokozutsumi, Yuruki Okada, Hisanori Yamasaki, Sho Kato
  • Publication number: 20140232318
    Abstract: A power conversion control device includes a modulation-wave generating unit generating a modulation wave based on output voltage phase angle command and modulation factor, a carrier-wave generating unit that, in a case of non-overmodulation state, generates a triangular wave or saw-tooth wave as the carrier wave, and, in a case of overmodulation state, generates, as the carrier wave, a signal fixed to ?1 in a first section that is a predetermined range centering on timing corresponding to a peak position of the modulation wave, generates, as the carrier wave, a signal fixed to +1 in a second section obtained by shifting the first section by a half cycle of the modulation wave, and generates, as the carrier wave, a triangular wave or saw-tooth wave in remaining third section, and a comparing unit that compares the carrier wave and the modulation wave and generates a switching signal.
    Type: Application
    Filed: September 30, 2011
    Publication date: August 21, 2014
    Applicant: Mitsubishi Electric Corporation
    Inventors: Ryo Yokozutsumi, Yuruki Okada, Hisanori Yamasaki, Sho Kato
  • Patent number: 8735213
    Abstract: A minute electrode, a photoelectric conversion device including the minute electrode, and manufacturing methods thereof are provided. A plurality of parallel groove portions and a region sandwiched between the groove portions are formed in a substrate, and a conductive resin is supplied to the groove portions and the region and is fixed, whereby the groove portions are filled with the conductive resin and the region is covered with the conductive resin. The supplied conductive resin is not expanded outward, and the electrode with a designed width can be formed. Part of the electrode is formed over the region sandwiched between the groove portions, thus, the area of a cross section in the short axis direction can be large, and a low resistance in the long axis direction can be obtained.
    Type: Grant
    Filed: December 14, 2011
    Date of Patent: May 27, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Yuji Oda, Takashi Hirose, Koichiro Tanaka, Sho Kato, Emi Koezuka
  • Patent number: 8643316
    Abstract: Based on rotation information of a synchronous machine detected by a rotation information detector, a controller causes a converter to boost a charge voltage of a capacitor so as to be higher than an induced voltage generated by the synchronous machine at a time of shifting to a coasting operation, maintains the charge voltage during the coasting operation, and performs weak field control so that the induced voltage generated by the synchronous machine becomes lower than a DC voltage at the time of shifting from the coasting operation to a power running operation or to a regenerative operation.
    Type: Grant
    Filed: August 3, 2009
    Date of Patent: February 4, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masaki Kono, Sho Kato
  • Patent number: 8604731
    Abstract: A control device for an AC rotating machine having a current limiting function of protecting the AC rotating machine and a driving unit such as an inverter from over-current, in which the control device has the reliable current limiting function in driving the AC rotating machine with known or unknown electrical constant. In the control device, a frequency correction value arithmetic unit has an amplification gain computing element for computing an amplification gain based on an electrical constant of the AC rotating machine and an amplifier for computing a frequency correction arithmetic value based on the amplification gain computed by the amplification gain computing element and the current of the AC rotating machine, in which the frequency correction arithmetic value is outputted as a frequency correction value in a predetermined running state of the AC rotating machine.
    Type: Grant
    Filed: March 11, 2009
    Date of Patent: December 10, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventors: Sho Kato, Yoshihiko Kimpara, Takahiko Kobayashi, Satoru Terashima
  • Patent number: 8507313
    Abstract: A fragile layer is formed in a region at a depth of less than 1000 nm from one surface of a single crystal semiconductor substrate, and a first impurity semiconductor layer and a first electrode are formed at the one surface side. After bonding the first electrode and a supporting substrate, the single crystal semiconductor substrate is separated using the fragile layer or the vicinity as a separation plane, thereby forming a first single crystal semiconductor layer over the supporting substrate. An amorphous semiconductor layer is formed on the first single crystal semiconductor layer, and a second single crystal semiconductor layer is formed by heat treatment for solid phase growth of the amorphous semiconductor layer. A second impurity semiconductor layer having a conductivity type opposite to that of the first impurity semiconductor layer and a second electrode are formed over the second single crystal semiconductor layer.
    Type: Grant
    Filed: March 22, 2012
    Date of Patent: August 13, 2013
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Fumito Isaka, Sho Kato, Koji Dairiki
  • Publication number: 20130113399
    Abstract: A control apparatus for an AC rotary machine includes a control circuit, a power converter, a current detector, and a voltage detector. The control circuit includes: an activation current instruction unit which generates a current instruction for activation; and a start phase setting unit which sets an initial rotation phase for activation control, based on the rotation direction of the AC rotary machine just after activation and on the polarity of current detected by the current detector just after activation. Thus, the current amplitude and torque shock just after activation control is started can be reduced, and assured and stable reactivation is allowed without causing the protection operation.
    Type: Application
    Filed: July 23, 2010
    Publication date: May 9, 2013
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Sho Kato, Hisanori Yamasaki, Masaki Kono, Keita Hatanaka
  • Publication number: 20130113398
    Abstract: A control apparatus for an AC rotary machine includes: a current detection section detecting current from a power converter to the AC rotary machine; and a control section generating a three-phase AC voltage instruction to the power converter, based on current detected by the current detection section and a torque instruction. The control section includes: an observer calculating a magnetic flux estimated value of the AC rotary machine, based on detected current and the voltage instruction; a current instruction calculation unit calculating current instruction values on rotational two axes, based on the torque instruction and the magnetic flux estimated value from the observer; and a voltage instruction calculation unit calculating the voltage instruction, based on the current instruction values from the current instruction calculation unit and the magnetic flux estimated value from the observer.
    Type: Application
    Filed: March 25, 2011
    Publication date: May 9, 2013
    Applicant: Mitsubishi Electric Corporation
    Inventors: Sho Kato, Hisanori Yamasaki, Keita Hatanaka, Hidetoshi Kitanaka, Yoshinori Yamashita
  • Publication number: 20130106329
    Abstract: A control apparatus for an AC rotating machine that can reliably and stably start up an AC rotating machine, particularly a synchronous motor using a permanent magnet, in position-sensorless vector control thereof, includes: a steady speed calculator that calculates, during steady state control of the AC rotating machine, a rotation angular frequency of the AC rotating machine based on an AC current and voltage commands; and a start-up speed calculator that calculates, during start-up control within a predetermined period after the AC rotating machine has been started up, the rotation angular frequency of the AC rotating machine based on the AC current and the voltage commands. The control apparatus corrects during the start-up control current commands so that the AC voltage amplitude of the voltage commands will be a constant value not more than the maximum output voltage of a power converter.
    Type: Application
    Filed: July 26, 2011
    Publication date: May 2, 2013
    Applicant: Mitsubishi Electric Corporation
    Inventors: Sho Kato, Hisanori Yamasaki, Keita Hatanaka, Hidetoshi Kitanaka, Yoshinori Yamashita
  • Patent number: 8420504
    Abstract: There are provided a semiconductor device having a structure which can realize not only suppression of a punch-through current but also reuse of a silicon wafer used for bonding, in manufacturing a semiconductor device using an SOI technique, and a manufacturing method thereof. A semiconductor film into which an impurity imparting a conductivity type opposite to that of a source region and a drain region is implanted is formed over a substrate, and a single crystal semiconductor film is bonded to the semiconductor film by an SOI technique to form a stacked semiconductor film. A channel formation region is formed using the stacked semiconductor film, thereby suppressing a punch-through current in a semiconductor device.
    Type: Grant
    Filed: November 9, 2010
    Date of Patent: April 16, 2013
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Sho Kato, Fumito Isaka, Tetsuya Kakehata, Hiromichi Godo, Akihisa Shimomura