Patents by Inventor Yukio Kawabata

Yukio Kawabata 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: 11959147
    Abstract: A top-blowing lance nozzle is configured to freely switch an adequate expansion condition so as to control an oxygen-blowing amount and a jetting velocity independently of each other without requiring a plurality of lance nozzles or a mechanically movable part. A lance nozzle is configured to blow refining oxygen to molten iron charged in a reaction vessel while a gas is blown from a top-blowing lance to the molten iron. One or more blowing holes for blowing a working gas are on an inner wall side surface of the nozzle, at a site where the lance nozzle has a minimum cross-sectional area in a nozzle axis direction or at a neighboring site of the site.
    Type: Grant
    Filed: April 2, 2020
    Date of Patent: April 16, 2024
    Assignee: JFE STEEL CORPORATION
    Inventors: Yumi Murakami, Nobuhiko Oda, Yusuke Fujii, Goro Okuyama, Shota Amano, Shinji Koseki, Shingo Sato, Yukio Takahashi, Ryo Kawabata, Naoki Kikuchi, Atsuo Yuasa
  • Patent number: 7388341
    Abstract: A vector control system for a permanent magnet synchronous motor, using a current control equivalent output value, a frequency instruction value, a current detection value, an inference phase error value, and a motor constant, identifies a motor resistance equivalent or a resistance setting error equivalent. Next, the vector control unit, using the identified value, corrects a set value R* equivalent of a voltage instruction calculation unit and a n inference phase error calculation unit. Thereby, a vector control system for a permanent magnet synchronous motor can realize a robust control characteristic for changing of a resistance constant of a motor in a low rotation speed area under position sensor-less control. Further, a vector control system for a permanent magnet synchronous motor can be applied in common in a system performing inexpensive current detection.
    Type: Grant
    Filed: August 17, 2005
    Date of Patent: June 17, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Kazuaki Tobari, Kiyoshi Sakamoto, Tsunehiro Endo, Yoshitaka Iwaji, Yukio Kawabata, Shigehisa Aoyagi
  • Patent number: 7294988
    Abstract: A rotary sensor that outputs two analog signals, such as one sine wave and one cosine wave and has multiple periods within one period of the electrical angle of a motor is employed. The motor is energized at each position for a specified length of time upon its startup by using multiple electrical angles corresponding to the multiple candidate absolute angles obtained from the rotary sensor signal as the initial position of the motor, and the electrical angle at which the motor acceleration becomes maximum is determined as the absolute angle. While the motor drive is in operation, on the other hand, the phase difference ?? between the phase of the motor at the counter electromotive voltage and the control phase is directly computed from the parameters of the motor, sensed current, voltage command and angle speed so as to correct the shifted position.
    Type: Grant
    Filed: December 6, 2005
    Date of Patent: November 13, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Toshiyuki Ajima, Hideki Miyazaki, Yukio Kawabata, Kiyoshi Sakamoto, Takao Yanai, Osamu Koizumi
  • Publication number: 20060125439
    Abstract: A rotary sensor that outputs two analog signals, such as one sine wave and one cosine wave and has multiple periods within one period of the electrical angle of a motor is employed. The motor is energized at each position for a specified length of time upon its startup by using multiple electrical angles corresponding to the multiple candidate absolute angles obtained from the rotary sensor signal as the initial position of the motor, and the electrical angle at which the motor acceleration becomes maximum is determined as the absolute angle. While the motor drive is in operation, on the other hand, the phase difference ?? between the phase of the motor at the counter electromotive voltage and the control phase is directly computed from the parameters of the motor, sensed current, voltage command and angle speed so as to correct the shifted position.
    Type: Application
    Filed: December 6, 2005
    Publication date: June 15, 2006
    Applicant: Hitachi, Ltd.
    Inventors: Toshiyuki Ajima, Hideki Miyazaki, Yukio Kawabata, Kiyoshi Sakamoto, Takao Yanai, Osamu Koizumi
  • Publication number: 20060055362
    Abstract: A vector control system for a permanent magnet synchronous motor, using a current control equivalent output value, a frequency instruction value, a current detection value, an inference phase error value, and a motor constant, identifies a motor resistance equivalent or a resistance setting error equivalent. Next, the vector control unit, using the identified value, corrects a set value R* equivalent of a voltage instruction calculation unit and a n inference phase error calculation unit. Thereby, a vector control system for a permanent magnet synchronous motor can realize a robust control characteristic for changing of a resistance constant of a motor in a low rotation speed area under position sensor-less control. Further, a vector control system for a permanent magnet synchronous motor can be applied in common in a system performing inexpensive current detection.
    Type: Application
    Filed: August 17, 2005
    Publication date: March 16, 2006
    Inventors: Kazuaki Tobari, Kiyoshi Sakamoto, Tsunehiro Endo, Yoshitaka Iwaji, Yukio Kawabata, Shigehisa Aoyagi
  • Patent number: 6828752
    Abstract: The present invention enables modulated wave signals having extremely small waveform distortion to be generated using a relatively simple circuit, and thereby it is possible to hold down vibrations and noise of a motor, which are attributable to torque ripples. In order to remove defects of the conventional techniques, the circuit generates a plurality of trapezoidal wave signals having at least two constant levels based on position sensing signals of magnetic pole of a motor, generates quasi-sinusoidal wave signals at a quasi-sinusoidal wave modulator based on the plurality of trapezoidal wave signals, and compares the quasi-sinusoidal wave signals with a carrier wave so as to perform PWM control of an inverter.
    Type: Grant
    Filed: June 27, 2003
    Date of Patent: December 7, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Junnosuke Nakatsugawa, Hitoshi Ohura, Tsuyoshi Tanaka, Tunehiro Endo, Yukio Kawabata
  • Publication number: 20040056632
    Abstract: The present invention enables modulated wave signals having extremely small waveform distortion to be generated using a relatively simple circuit, and thereby it is possible to hold down vibrations and noise of a motor, which are attributable to torque ripples. In order to remove defects of the conventional techniques, the circuit generates a plurality of trapezoidal wave signals having at least two constant levels based on position sensing signals of magnetic pole of a motor, generates quasi-sinusoidal wave signals at a quasi-sinusoidal wave modulator based on the plurality of trapezoidal wave signals, and compares the quasi-sinusoidal wave signals with a carrier wave so as to perform PWM control of an inverter.
    Type: Application
    Filed: June 27, 2003
    Publication date: March 25, 2004
    Inventors: Junnosuke Nakatsugawa, Hitoshi Ohura, Tsuyoshi Tanaka, Tunehiro Endo, Yukio Kawabata
  • Patent number: 6657413
    Abstract: Providing control apparatus with a maximum torque/current ratio control means by which the relationship between the maximum torque and current amplitudes and the relationship between the maximum torque and current phases are converted to numeric expressions including one or more than one linear function with the torque taken as the parameter, then the current amplitude command and current phase command data that yields a maximum torque is computed, and computed data is sent as an output signal.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: December 2, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Junnosuke Nakatsugawa, Yukio Kawabata, Tsunehiro Endo, Masashi Kitamura, Junya Kaneda
  • Patent number: 6642681
    Abstract: After the rotor position has been fixed prior to the start of a motor, the driving mode can be rapidly switched to sensorless driving and the motor can be started and controlled, by conducting current conversions in such a power supply pattern that increases the starting output torque of the motor, and controlling the inverter output voltage.
    Type: Grant
    Filed: February 26, 2002
    Date of Patent: November 4, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Kawabata, Tsunehiro Endo, Makoto Ishii, Yuhachi Takakura, Toru Inoue
  • Patent number: 6626002
    Abstract: In a motor driving unit controlled by switching to/from PWM control from/to PAM control so that the maximum limit of motor speed can be increased and, at the same time, the unit can be operated at maximum efficiency during steady-state operation, the motor speed is controlled by maintaining the DC voltage command to the converter control circuit constant, but altering the conduction ratio command value to the inverter control circuit when the load to the motor is low, and by maintaining the conduction ratio command to the inverter control circuit constant, but altering the DC voltage command to the converter control circuit. There is a commutating phase control circuit that alters the commutating timing of the coil of the motor, and the motor is so controlled that the efficiency reaches the maximum limit during steady-state operation and the speed reaches the maximum limit during high-speed operation.
    Type: Grant
    Filed: February 26, 2001
    Date of Patent: September 30, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Yasuo Notohara, Yukio Kawabata, Kazuo Tahara, Makoto Ishii, Yuhachi Takakura, Hiroshi Shinozaki
  • Patent number: 6603280
    Abstract: A converter module which receives an AC voltage, converts the AC voltage to a DC voltage, and outputs the DC voltage to a circuit for driving a motor. The converter module includes a switching device, a diode, and a control circuit which controls the DC voltage output by the converter module by controlling the switching device. The control circuit includes a plurality of DC voltage detection terminals which detect the DC voltage output by the converter module with respective different DC voltage detection gains, a selector which selects at least one of the DC voltage detection terminals in accordance with an external signal indicative of a speed of the motor, and outputs a DC voltage detection value, and a controller which controls the DC voltage output by the converter module in accordance with the DC voltage detection value output by the selector.
    Type: Grant
    Filed: January 18, 2001
    Date of Patent: August 5, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Yasuo Notohara, Yukio Kawabata, Kazuo Tahara, Makoto Ishii, Yuhachi Takakura
  • Patent number: 6570358
    Abstract: In order to supply an AC motor control apparatus which identifies the type of motor automatically, the AC motor control apparatus has a motor type identification means by which the type of motor connected to the motor control apparatus is identified by issuing the appropriate voltage command for motor type identification and judging from the detected current whether the motor rotor is equipped with a magnet and has magnetic salience. The AC motor control apparatus has a control scheme selection means which selects the appropriate control scheme according to the above-identified type of motor and controls the driving of the motor.
    Type: Grant
    Filed: October 18, 2001
    Date of Patent: May 27, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Junnosuke Nakatsugawa, Tsunehiro Endo, Hiromi Inaba, Yoshitaka Iwaji, Yukio Kawabata, Hiroyuki Tomita, Junji Kato
  • Patent number: 6534948
    Abstract: A motor driving system is disclosed. The circuit includes a power converter for supplying a brushless motor having a permanent magnetic rotor with pulse-width modulation controlled driving power, a magnetic-pole position detector for detecting a magnetic-pole position of the motor rotor, a speed detector for detecting a rotational speed of the motor according to an output signal of the magnetic-pole position detector, a speed controller for outputting a deviation of an output signal of the rotational speed detector from a speed instruction, an instruction signal generating circuit for generating a plurality of instruction signals in response to an output signal of the speed controller, a circuit for generating modulated waves by selecting one of the plurality of instruction signals according to the magnetic-pole position of the motor, and a driving ct for controlling the power converter by means of pulse width modulation according to the modulated waves.
    Type: Grant
    Filed: February 21, 2001
    Date of Patent: March 18, 2003
    Assignees: Hitachi, Ltd., Hitachi Haramachi Electronics Co., Ltd.
    Inventors: Hitoshi Ohura, Tsuyoshi Tanaka, Yukio Kawabata
  • Publication number: 20020180398
    Abstract: Providing control apparatus with a maximum torque/current ratio control means by which the relationship between the maximum torque and current amplitudes and the relationship between the maximum torque and current phases are converted to numeric expressions including one or more than one linear function with the torque taken as the parameter, then the current amplitude command and current phase command data that yields a maximum torque is computed, and computed data is sent as an output signal.
    Type: Application
    Filed: September 20, 2001
    Publication date: December 5, 2002
    Applicant: HITACHI, LTD.
    Inventors: Junnosuke Nakatsugawa, Yukio Kawabata, Tsunehiro Endo, Masashi Kitamura, Junya Kaneda
  • Publication number: 20020167289
    Abstract: In order to supply an AC motor control apparatus which identifies the type of motor automatically, the AC motor control apparatus has a motor type identification means by which the type of motor connected to the motor control apparatus is identified by issuing the appropriate voltage command for motor type identification and judging from the detected current whether the motor rotor is equipped with a magnet and has magnetic salience. The AC motor control apparatus has a control scheme selection means which selects the appropriate control scheme according to the above-identified type of motor and controls the driving of the motor.
    Type: Application
    Filed: October 18, 2001
    Publication date: November 14, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Junnosuke Nakatsugawa, Tsunehiro Endo, Hiromi Inaba, Yoshitaka Iwaji, Yukio Kawabata, Hiroyuki Tomita, Junji Kato
  • Patent number: 6479956
    Abstract: The present invention supplies a position detection circuit, and a motor controller, that can not only obtain rotor position detection signals properly over the entire PWM control region, but also obtain these signals properly during PAM control. In a brushless motor controller based on the present invention to detect the magnetic pole position of the stator in the motor in accordance with the stator coil terminal voltages of multiple phases and control the energization of the stator coils, the comparison result information signal, after being obtained through comparison between the detected voltage values corresponding to the foregoing terminal voltages, and a reference voltage value, is directly entered into control circuits, then the position of the rotor in the motor is properly detected immediately after power-on switching, without a rotor position detection inhibition time interval being provided, and the motor is controlled properly.
    Type: Grant
    Filed: January 16, 2001
    Date of Patent: November 12, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Kawabata, Yasuo Notohara, Kazuo Tahara, Yuhachi Takakura, Makoto Ishii, Hiroshi Shinozaki
  • Publication number: 20020117989
    Abstract: After the rotor position has been fixed prior to the start of a motor, the driving mode can be rapidly switched to sensorless driving and the motor can be started and controlled, by conducting current conversions in such a power supply pattern that increases the starting output torque of the motor, and controlling the inverter output voltage.
    Type: Application
    Filed: February 26, 2002
    Publication date: August 29, 2002
    Inventors: Yukio Kawabata, Tsunehiro Endo, Makoto Ishii, Yuhachi Takakura, Toru Inoue
  • Patent number: 6337548
    Abstract: An apparatus such as an air conditioner, refrigerator or washing machine having a control apparatus for use in a brushless motor facing a part of a compressor and/or blower of the apparatus. The control apparatus includes a voltage detector for generating a detection voltage in response to a terminal voltage of plural phases of a stator winding of the brushless motor, a standard voltage generator for generating a standard voltage, a comparator for outputting a comparison result information signal by comparing the detection voltage and said standard voltage, a controller for detecting a rotation position of a rotor of the brushless motor according to the comparison result information signal which is outputted from the comparator and for outputting an electric supply control signal, and an output unit for supplying electric power to the stator winding according to the electric supply control signal.
    Type: Grant
    Filed: February 16, 2001
    Date of Patent: January 8, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Kawabata, Yasuo Notohara, Kazuo Tahara
  • Publication number: 20010040440
    Abstract: A motor driving system according to the present invention comprises a power converter for supplying a brushless motor having a permanent magnetic rotor with pulse-width modulation controlled driving power; a magnetic-pole position detector for detecting a magnetic-pole position of the motor rotor; a speed detecting means for detecting a rotational speed of the motor according to an output signal of the magnetic-pole position detector; a speed control operation means for outputting a deviation of an output signal of the speed detecting means from a speed instruction; a means for generating a plurality of instruction signals in response to an output signal of the speed control operation means; a means for generating modulated waves by selecting one of the plurality of instruction signals according to the output signal of the speed control operation means; and a means for controlling the power converter by means of pulse width modulation according to the modulated waves.
    Type: Application
    Filed: February 21, 2001
    Publication date: November 15, 2001
    Inventors: Hitoshi Ohura, Tsuyoshi Tanaka, Yukio Kawabata
  • Publication number: 20010004197
    Abstract: An apparatus such as an air conditioner, refrigerator or washing machine having a control apparatus for use in a brushless motor facing a part of a compressor and/or blower of the apparatus. The control apparatus includes a voltage detector for generating a detection voltage in response to a terminal voltage of plural phases of a stator winding of the brushless motor, a standard voltage generator for generating a standard voltage, a comparator for outputting a comparison result information signal by comparing the detection voltage and said standard voltage, a controller for detecting a rotation position of a rotor of the brushless motor according to the comparison result information signal which is outputted from the comparator and for outputting an electric supply control signal, and an output unit for supplying electric power to the stator winding according to the electric supply control signal.
    Type: Application
    Filed: February 16, 2001
    Publication date: June 21, 2001
    Inventors: Yukio Kawabata, Yasuo Notohara, Kazuo Tahara