Patents by Inventor Mitsuo Kawaji

Mitsuo Kawaji 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: 7113414
    Abstract: An inverter control device for driving a motor with small size, light weight and low cost is provided. The inverter control device includes a first motor voltage command corrector that corrects a voltage command of each phase by multiplying the each phase voltage command by a PN voltage correction coefficient, and a second motor voltage command corrector that corrects again the each phase voltage command once corrected by the first motor voltage command corrector, only when any one of the phase voltage commands corrected by the first motor voltage command corrector is larger than the inverter DC voltage, by multiplying the voltage command of each phase corrected by the first motor voltage command corrector by the inverter DC voltage value, and dividing the product of the multiplication by the maximum value of the phase voltage commands corrected by the first motor voltage command corrector.
    Type: Grant
    Filed: March 26, 2004
    Date of Patent: September 26, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hideo Matsushiro, Mitsuo Kawaji, Tomohiro Sugimoto, Hideki Nakata, Mitsuo Ueda
  • Patent number: 7095208
    Abstract: A reactor having a predetermined small capacity is connected to a rectifier, and a capacitor having a predetermined small capacity is connected between DC bus lines of the inverter, so that a small, light and low-cost inverter controller for driving a motor can be implemented, and even when an inverter DC voltage largely fluctuates and it is difficult to drive the motor, the motor can be kept driving by operating the inverter such that a voltage applied to the motor may stay constant by a motor voltage command corrector which generates a motor voltage command correction value of the motor.
    Type: Grant
    Filed: March 30, 2004
    Date of Patent: August 22, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mitsuo Kawaji, Hideo Matsushiro, Tomohiro Sugimoto
  • Patent number: 6984948
    Abstract: In a motor control apparatus of the present invention, a control section which receives an input voltage to an inverter circuit, a motor current flowing to a brushless motor and a motor current command value indicating the value of a current required to flow to the inverter circuit, and controls the inverter circuit by maintaining a phase of the voltage applied to the brushless motor when the value of the input voltage to the inverter circuit is smaller than the value of a voltage required to be applied to the brushless motor.
    Type: Grant
    Filed: December 10, 2003
    Date of Patent: January 10, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hideki Nakata, Mitsuo Ueda, Hideo Matsushiro, Masanori Ogawa, Mitsuo Kawaji, Tomohiro Sugimoto
  • Patent number: 6972541
    Abstract: An inverter control device for driving a motor with small size, light weight and low cost is provided. The inverter control device generates PN voltage correction coefficient by dividing the reference DC voltage by the detected DC voltage, and corrects the voltage command of each phase by multiplying the voltage command of each phase obtained by the motor voltage command generator with the PN voltage correction coefficient output from the PN voltage corrector, thus resulting in the corrected motor voltage command. The inverter control device has, in generating PN voltage correction coefficient, a first mode in which the PN voltage correction coefficient is set to 1 when the DC voltage value is more than the reference DC voltage, and a second mode in which the value obtained by dividing the reference DC voltage by the detected DC voltage is set to the PN voltage correction coefficient.
    Type: Grant
    Filed: March 26, 2004
    Date of Patent: December 6, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hideo Matsushiro, Mitsuo Kawaji, Tomohiro Sugimoto
  • Patent number: 6958589
    Abstract: A reactor having a predetermined small capacity is connected to a rectifier, and a capacitor having a predetermined small capacity is connected between DC bus lines of the inverter. A PN voltage corrector calculates a ratio of the DC voltage detection value of the inverter obtained by the PN voltage detector to a predetermined DC voltage reference value of the inverter to thereby generate a PN voltage correction factor. A beat amount corrector calculates a fluctuation amount of the motor current from the motor current detection value obtained by the motor current detector and generates a reverse phase component of the motor current fluctuation amount. Thus, a small, light and low-cost inverter controller can be implemented.
    Type: Grant
    Filed: April 1, 2004
    Date of Patent: October 25, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mitsuo Kawaji, Hideo Matsushiro, Tomohiro Sugimoto
  • Patent number: 6924618
    Abstract: An inverter controller for driving a motor includes a rectifier having a reactor, an inverter, a capacitor, a generator which generates a voltage command value for each phase of the motor, a detector which detects a DC voltage between the DC buses of the inverter, a first corrector which calculates a voltage correction coefficient by comparing the DC voltage with a predetermined DC reference voltage, a second corrector which corrects the voltage command value by multiplying the voltage command value and the voltage correction coefficient, a selector which selects either two-phase modulation or three-phase modulation as a modulation type, a computer that computes a carrier frequency, and a pulse width modulation controller which controls a pulse width modulation so that a value of a voltage to be applied to the motor equals to the corrected voltage command value, by using the selected modulation type and the selected carrier frequency.
    Type: Grant
    Filed: March 24, 2004
    Date of Patent: August 2, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hideo Matsushiro, Tomohiro Sugimoto, Mitsuo Kawaji
  • Publication number: 20040246641
    Abstract: An inverter control unit for motor driving includes a rectifier circuit for converting into a DC power a first AC power inputted from an AC power supply, which includes a diode bridge and a reactor connected to an AC input side or a DC output side of the diode bridge and having a small inductance, and an inverter for converting the DC power from the rectifier circuit into a second AC power so as to output the second AC power to a motor. Furthermore, a capacitor for absorbing regenerative energy of the motor, which has a small capacitance and an overvoltage protecting circuit whose impedance is lowered by overvoltage are connected between DC buses of the inverter.
    Type: Application
    Filed: April 20, 2004
    Publication date: December 9, 2004
    Inventors: Tomohiro Sugimoto, Hideo Matsushiro, Mitsuo Kawaji, Akihiro Kyogoku
  • Publication number: 20040232877
    Abstract: A reactor (5) having a predetermined small capacity is connected to a rectifier (2), and a capacitor (6) having a predetermined small capacity which is connected between DC bus lines of the inverter (3). A PN voltage corrector (10) calculates a ratio of the DC voltage detection value of the inverter obtained by the PN voltage detector (9) to a predetermined DC voltage reference value of the inverter (3) to thereby generate a PN voltage correction factor. A beat amount corrector (16) calculates a fluctuation amount of the motor current from the motor current detection value obtained by the motor current detector (15) and generates a reverse phase component of the motor current fluctuation amount. Thus, a small, light and low-cost inverter controller can be implemented.
    Type: Application
    Filed: April 1, 2004
    Publication date: November 25, 2004
    Inventors: Mitsuo Kawaji, Hideo Matsushiro, Tomohiro Sugimoto
  • Publication number: 20040232876
    Abstract: An inverter control device for driving a motor with small size, light weight and low cost is provided. The inverter control device generates PN voltage correction coefficient by dividing the reference DC voltage by the detected DC voltage, and corrects the voltage command of each phase by multiplying the voltage command of each phase obtained by the motor voltage command generator with the PN voltage correction coefficient output from the PN voltage corrector, thus resulting in the corrected motor voltage command. The inverter control device has, in generating PN voltage correction coefficient, a first mode in which the PN voltage correction coefficient is set to 1 when the DC voltage value is more than the reference DC voltage, and a second mode in which the value obtained by dividing the reference DC voltage by the detected DC voltage is set to the PN voltage correction coefficient.
    Type: Application
    Filed: March 26, 2004
    Publication date: November 25, 2004
    Inventors: Hideo Matsushiro, Mitsuo Kawaji, Tomohiro Sugimoto
  • Patent number: 6822417
    Abstract: A control apparatus of a synchronous reluctance motor includes a torque current correction unit (16) that generates a torque current command tracing a load torque so as to make the output torque of the motor coincide with the load torque. The control apparatus may further include a position and speed estimation unit (13) that estimates the position and speed based on three phase voltage equation to improve control performance in a voltage saturation state.
    Type: Grant
    Filed: May 11, 2004
    Date of Patent: November 23, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mitsuo Kawaji, Hideo Matsushiro, Keizo Matsui
  • Publication number: 20040228151
    Abstract: An inverter control device for driving a motor with small size, light weight and low cost is provided. The inverter control device includes a first motor voltage command corrector that corrects a voltage command of each phase by multiplying the each phase voltage command by a PN voltage correction coefficient, and a second motor voltage command corrector that corrects again the each phase voltage command once corrected by the first motor voltage command corrector, only when any one of the phase voltage commands corrected by the first motor voltage command corrector is larger than the inverter DC voltage, by multiplying the voltage command of each phase corrected by the first motor voltage command corrector by the inverter DC voltage value, and dividing the product of the multiplication by the maximum value of the phase voltage commands corrected by the first motor voltage command corrector.
    Type: Application
    Filed: March 26, 2004
    Publication date: November 18, 2004
    Inventors: Hideo Matsushiro, Mitsuo Kawaji, Tomohiro Sugimoto, Hideki Nakata, Mitsuo Ueda
  • Publication number: 20040217728
    Abstract: A reactor (11) having a predetermined small capacity is connected to a rectifier (2), and a capacitor (12) having a predetermined small capacity is connected between DC bus lines of the inverter (3), so that a small, light and low-cost inverter controller for driving a motor can be implemented, and even when an inverter DC voltage largely fluctuates and it is difficult to drive the motor, the motor can be kept driving by operating the inverter such that a voltage applied to the motor may stay constant by a motor voltage command corrector (17) which generates a motor voltage command correction value of the motor.
    Type: Application
    Filed: March 30, 2004
    Publication date: November 4, 2004
    Inventors: Mitsuo Kawaji, Hideo Matsushiro, Tomohiro Sugimoto
  • Publication number: 20040207360
    Abstract: An inverter controller for driving a motor includes a rectifier having a reactor, an inverter, a capacitor, a generator which generates a voltage command value for each phase of the motor, a detector which detects a DC voltage between the DC buses of the inverter, a first corrector which calculates a voltage correction coefficient by comparing the DC voltage with a predetermined DC reference voltage, a second corrector which corrects the voltage command value by multiplying the voltage command value and the voltage correction coefficient, a selector which selects either two-phase modulation or three-phase modulation as a modulation type, a computer that computes a carrier frequency, and a pulse width modulation controller which controls a pulse width modulation so that a value of a voltage to be applied to the motor equals to the corrected voltage command value, by using the selected modulation type and the selected carrier frequency.
    Type: Application
    Filed: March 24, 2004
    Publication date: October 21, 2004
    Inventors: Hideo Matsushiro, Tomohiro Sugimoto, Mitsuo Kawaji
  • Publication number: 20040201358
    Abstract: A control apparatus of a synchronous reluctance motor includes a torque current correction unit (16) that generates a torque current command tracing a load torque so as to make the output torque of the motor coincide with the load torque. the control apparatus may further include a position and speed estimation unit (13) that estimates the position and speed based on three phase voltage equation to improve control performance in a voltage saturation state.
    Type: Application
    Filed: May 11, 2004
    Publication date: October 14, 2004
    Inventors: Mitsuo Kawaji, Hideo Matsushiro, Keizo Matsui
  • Publication number: 20040124807
    Abstract: In a motor control apparatus of the present invention, a control section which receives an input voltage to an inverter circuit, a motor current flowing to a brushless motor and a motor current command value indicating the value of a current required to flow to the inverter circuit, and controls the inverter circuit by maintaining a phase of the voltage applied to the brushless motor when the value of the input voltage to the inverter circuit is smaller than the value of a voltage required to be applied to the brushless motor.
    Type: Application
    Filed: December 10, 2003
    Publication date: July 1, 2004
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hideki Nakata, Mitsuo Ueda, Hideo Matsushiro, Masanori Ogawa, Mitsuo Kawaji, Tomohiro Sugimoto
  • Patent number: 4101879
    Abstract: A cursor movement control a screen-segmented display apparatus in which the cursor is moved line by line within one divided section. The apparatus comprises a horizontal cursor register for storing the horizontal position of the cursor on display, a vertical cursor register for storing the vertical position of the cursor on display, a starting column register for storing the cursor starting column on one divided section, and a last column register for storing the cursor last column on the section. The contents of the horizontal cursor register are changed by pulses of an external pulse source generated in response to a command for moving the cursor. When the contents of the horizontal cursor register coincide with that of the last column register, the horizontal cursor register is stored with the starting column of the starting column register and at the same time the contents of the vertical cursor register are changed to set the cursor forward by one line.
    Type: Grant
    Filed: December 13, 1976
    Date of Patent: July 18, 1978
    Assignee: Hitachi, Ltd.
    Inventors: Mitsuo Kawaji, Toshio Usui, Masaichiro Kawano