Patents by Inventor Toshisada Mitsui

Toshisada Mitsui 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: 20130066501
    Abstract: It is desirable to enhance efficiency of a power conversion device in both of a case where a motor generator which is an electric rotating machine is operated as a motor and a case where the motor generator is operated as a generator by performing regeneration braking. At the time of performing regeneration braking, strength of regeneration braking can be controlled by making an inverter circuit conductive in response to a predetermined phase of an AC output which the inverter circuit generates and by controlling a conduction width. Due to such a control, the number of times of switching a semiconductor element which constitutes the inverter circuit can be reduced thus suppressing heat generation of the semiconductor element and also the efficiency of the power conversion device can be enhanced. Further, the enhancement of efficiency of the power conversion device can be realized also in a motor operation and hence, it is also possible to enhance efficiency with respect to the traveling of a vehicle.
    Type: Application
    Filed: April 28, 2010
    Publication date: March 14, 2013
    Applicant: Hitachi, Ltd.
    Inventors: Kazuto Oyama, Hideki Miyazaki, Kimihisa Furukawa, Toshisada Mitsui, Shingo Nishiguchi, Akinori Kamiya
  • Publication number: 20130033205
    Abstract: A control circuit of a power conversion device calculates voltage command signals for determining timings for making switching elements of a power switching circuit continuous by performing feed forward control on the basis of input information, and feedback control on the basis of the input information and current values of AC output, for each of the d axis and the q axis of a motor.
    Type: Application
    Filed: April 28, 2010
    Publication date: February 7, 2013
    Applicant: HITACHI, LTD.
    Inventors: Kimihisa Furukawa, Toshisada Mitsui, Shingo Nishiguchi, Kazuto Ooyama, Hideki Miyazaki, Akinori Kamiya
  • Patent number: 8232756
    Abstract: An object of the present invention is to provide a motor control apparatus that can perform an abnormality diagnosis of current sensors and achieve cost reduction. When the outputs from three current sensors, which detect individual phase currents of a 3-phase AC current supplied from an inverter to a 3-phase AC motor, indicate that the sum of the individual phase currents of the 3-phase AC current is greater than a predetermined value, a sensor abnormality judgment unit of a motor control unit judges that one of the three current sensors is abnormal. The sensor abnormality judgment unit identifies an abnormal current sensor, which is one of the three current sensors, and performs calculations in accordance with the remaining two normal current sensors to output the current in the phase detected by the abnormal current sensor.
    Type: Grant
    Filed: November 14, 2008
    Date of Patent: July 31, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Shigeyuki Yoshihara, Hirokazu Matsui, Kohei Myoen, Toshisada Mitsui
  • Publication number: 20110266992
    Abstract: A power conversion device includes a power switching circuit that has a plurality of series circuits in each of which a switching element that operates as an upper arm and a switching element that operates as a lower arm are connected in series, and a control circuit that generates control signals for controlling the continuity or discontinuity of the switching elements, and, if the relationship between the state of a switching element in a control cycle and the state of the switching element in the next control cycle is a discontinuous relationship, that additionally performs control to make the switching element continuous or discontinuous on the basis of the state of the switching element in the control cycle and the state of the switching element in the next control cycle.
    Type: Application
    Filed: February 16, 2011
    Publication date: November 3, 2011
    Applicant: Hitachi, Ltd.
    Inventors: Shingo NISHIGUCHI, Kimihisa Furukawa, Akinori Kamiya, Toshisada Mitsui, Kazuto Ooyama
  • Publication number: 20110193509
    Abstract: A power conversion device includes a power switching circuit that supplies AC voltages generated between switching elements operating as upper arms and switching elements operating as lower arms, and a control circuit that generates and supplies to the driver circuit signals for controlling the switching operation of the switching elements by a PWM method in a first operational region in which frequency of an AC power to be outputted is low, and that generates and supplies to the driver circuit signals for controlling the switching operation of the switching elements at timings based upon the phase of the AC power to be outputted in an operational region in which the frequency of the AC power to be outputted is higher than in the first operational region.
    Type: Application
    Filed: February 9, 2011
    Publication date: August 11, 2011
    Applicant: Hitachi, Ltd.
    Inventors: Kazuto OOYAMA, Toshisada Mitsui, Shingo Nishiguchi, Kimihisa Furukawa
  • Publication number: 20090133947
    Abstract: An object of the present invention is to provide a motor control apparatus that can perform an abnormality diagnosis of current sensors and achieve cost reduction. When the outputs from three current sensors, which detect individual phase currents of a 3-phase AC current supplied from an inverter to a 3-phase AC motor, indicate that the sum of the individual phase currents of the 3-phase AC current is greater than a predetermined value, a sensor abnormality judgment unit of a motor control unit judges that one of the three current sensors is abnormal. The sensor abnormality judgment unit identifies an abnormal current sensor, which is one of the three current sensors, and performs calculations in accordance with the remaining two normal current sensors to output the current in the phase detected by the abnormal current sensor.
    Type: Application
    Filed: November 14, 2008
    Publication date: May 28, 2009
    Applicant: HITACHI, LTD.
    Inventors: Shigeyuki YOSHIHARA, Hirokazu Matsui, Kohei Myoen, Toshisada Mitsui
  • Patent number: 7406389
    Abstract: A state detecting system which can detect state of power storage at high precision even with lesser characteristic data to be used for calculation, and a device employing the same. The state detecting system has a memory for storing a characteristic data, calculation information, and set information, an arithmetic unit for calculating state information indicative of state of said power storage and calculating correction information for performing correction, a first correcting unit for correcting input of said arithmetic means, and a second correcting unit for correcting information stored or set in the storage.
    Type: Grant
    Filed: June 22, 2006
    Date of Patent: July 29, 2008
    Assignees: Hitachi, Ltd., Shin-Kobe Electric Machinery Co., Ltd.
    Inventors: Akihiko Emori, Akihiko Kudou, Shigeyuki Yoshihara, Hideki Miyazaki, Toshisada Mitsui, Mitsuyuki Hombu, Kazuyoshi Sasazawa
  • Publication number: 20060247871
    Abstract: A state detecting system which can detect state of power storage at high precision even with lesser characteristic data to be used for calculation, and a device employing the same. The state detecting system has a memory for storing a characteristic data, calculation information, and set information, an arithmetic unit for calculating state information indicative of state of said power storage and calculating correction information for performing correction, a first correcting unit for correcting input of said arithmetic means, and a second correcting unit for correcting information stored or set in the storage.
    Type: Application
    Filed: June 22, 2006
    Publication date: November 2, 2006
    Applicant: HITACHI, LTD.
    Inventors: Akihiko Emori, Akihiko Kudou, Shigeyuki Yoshihara, Hideki Miyazaki, Toshisada Mitsui, Mitsuyuki Hombu, Kazuyoshi Sasazawa
  • Patent number: 7085661
    Abstract: A state detecting system which can detect state of power storage at high precision even with lesser characteristic data to be used for calculation, and a device employing the same. The state detecting system has a memory for storing a characteristic data, calculation information, and set information, an arithmetic unit for calculating state information indicative of state of said power storage and calculating correction information for performing correction, a first correcting unit for correcting input of said arithmetic means, and a second correcting unit for correcting information stored or set in the storage.
    Type: Grant
    Filed: January 10, 2005
    Date of Patent: August 1, 2006
    Assignees: Hitachi, Ltd., Shin-Kobe Electric Machinery Co., Ltd.
    Inventors: Akihiko Emori, Akihiko Kudou, Shigeyuki Yoshihara, Hideki Miyazaki, Toshisada Mitsui, Mitsuyuki Hombu, Kazuyoshi Sasazawa
  • Publication number: 20050119856
    Abstract: A state detecting system which can detect state of power storage at high precision even with lesser characteristic data to be used for calculation, and a device employing the same. The state detecting system has a memory for storing a characteristic data, calculation information, and set information, an arithmetic unit for calculating state information indicative of state of said power storage and calculating correction information for performing correction, a first correcting unit for correcting input of said arithmetic means, and a second correcting unit for correcting information stored or set in the storage.
    Type: Application
    Filed: January 10, 2005
    Publication date: June 2, 2005
    Applicants: Hitachi, LTD., Shin-Kobe Electric Machinery Co.
    Inventors: Akihiko Emori, Akihiko Kudou, Shigeyuki Yoshihara, Hideki Miyazaki, Toshisada Mitsui, Mitsuyuki Hombu, Kazuyoshi Sasazawa
  • Publication number: 20030195719
    Abstract: A state detecting system which can detect state of power storage at high precision even with lesser characteristic data to be used for calculation, and a device employing the same. The state detecting system has a memory for storing a characteristic data, calculation information, and set information, an arithmetic unit for calculating state information indicative of state of said power storage and calculating correction information for performing correction, a first correcting unit for correcting input of said arithmetic means, and a second correcting unit for correcting information stored or set in the storage.
    Type: Application
    Filed: March 14, 2003
    Publication date: October 16, 2003
    Applicants: Hitachi, Ltd., Shin-Kobe Electric Machinery Co.
    Inventors: Akihiko Emori, Akihiko Kudou, Shigeyuki Yoshihara, Hideki Miyazaki, Toshisada Mitsui, Mitsuyuki Hombu, Kazuyoshi Sasazawa
  • Patent number: 6194865
    Abstract: An apparatus for steadily and efficiently controlling a synchronous motor is equipped with a function for generating dq-axis current commands so that the terminal voltage of the synchronous motor may not exceed the voltage which a power converter can output even at a current transition time, a current control function for correcting a fluctuation of a D.C. input voltage, and a function for eliminating the D.C. input power to zero when performing field weakening control. The dq-axis current command generator is so built as to retrieve current command tables listing high-efficiency data in advance by torque commands and rotational speeds of the synchronous motor. There are a plurality of current command tables converting maximum terminal voltages of the synchronous motor. A means is provided to select an optimum one of said current command tables according to the D.C. input voltage. In this case, a value obtained by subtracting a preset value from the D.C.
    Type: Grant
    Filed: July 7, 1999
    Date of Patent: February 27, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Toshisada Mitsui, Nobunori Matsudaira, Eiichi Ohtsu
  • Patent number: 6154002
    Abstract: A control apparatus of an electric motor vehicle includes a device for operating an initial magnetic pole location based on three phase magnetic pole location signal pulses of a permanent magnet electric motor upon starting the electric motor vehicle, a device for operating a magnetic pole phase of the permanent magnet electric motor on the basis of the initial magnetic pole location, a rotation pulse of the permanent magnet electric motor, and a correction value which are operated with the rise and fall of the three phase magnetic pole location signal pulse after the starting, a device for determining a current to be supplied into the permanent magnet electric motor based on the magnetic pole phase and a torque reference value, and a device for correcting the magnetic pole phase when a predetermined one of the three phase magnetic pole location signal pulses rises or falls.
    Type: Grant
    Filed: November 24, 1999
    Date of Patent: November 28, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Katsuyuki Izumisawa, Sanshiro Obara, Toshisada Mitsui
  • Patent number: 6072288
    Abstract: A control apparatus of an electric motor vehicle includes a device for operating an initial magnetic pole location based on three phase magnetic pole location signal pulses of a permanent magnet electric motor upon starting the electric motor vehicle, a device for operating a magnetic pole phase of the permanent magnet electric motor on the basis of the initial magnetic pole location, a rotation pulse of the permanent magnet electric motor, and a correction value which are operated with the rise and fall of the three phase magnetic pole location signal pulse after the starting, a device for determining a current to be supplied into the permanent magnet electric motor based on the magnetic pole phase and a torque reference value, and a device for correcting the magnetic pole phase when a predetermined one of the three phase magnetic pole location signal pulses rises or falls.
    Type: Grant
    Filed: February 24, 1998
    Date of Patent: June 6, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Katsuyuki Izumisawa, Sanshiro Obara, Toshisada Mitsui