Patents by Inventor Yasuaki Aoki

Yasuaki Aoki 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: 20200136549
    Abstract: A controller of a rotating electric machine includes a current detector detecting a voltage of each of shunt resistors in at least two phases from among the shunt resistors in three phases during an electric current flowing period in which the shunt resistors in the at least two phases have an electric current flowing therein; and a signal generator setting a switching mode of each of switches forming an inverter for controlling an estimated angular velocity to an instruction angular velocity based on the detected voltage. The signal generator sets a switching mode to flow the electric current in the shunt resistors in the at least two phases during at least part of one half of a modulation cycle of control of the estimated angular velocity.
    Type: Application
    Filed: October 24, 2019
    Publication date: April 30, 2020
    Inventor: Yasuaki AOKI
  • Patent number: 10432124
    Abstract: In a current detection apparatus, a corrector obtains first current-value pairs of the plural values of the corrective first phase current and the respective plural values of the corrective first phase bus-based current synchronized with the plural values of the corrective first phase current. The corrector obtains second current-value pairs of the plural values of the corrective second phase current and the respective plural values of the corrective second phase bus-based current synchronized with the plural pairs of the corrective second phase current. The corrector corrects at least target first and second phase currents detected by a first current detector based on the obtained first current-value pairs and the second current-value pairs to thereby align amplitudes of the respective target first and second phase currents with each other.
    Type: Grant
    Filed: October 25, 2018
    Date of Patent: October 1, 2019
    Assignee: DENSO CORPORATION
    Inventor: Yasuaki Aoki
  • Publication number: 20190131904
    Abstract: In a current detection apparatus, a corrector obtains first current-value pairs of the plural values of the corrective first phase current and the respective plural values of the corrective first phase bus-based current synchronized with the plural values of the corrective first phase current. The corrector obtains second current-value pairs of the plural values of the corrective second phase current and the respective plural values of the corrective second phase bus-based current synchronized with the plural pairs of the corrective second phase current. The corrector corrects at least target first and second phase currents detected by a first current detector based on the obtained first current-value pairs and the second current-value pairs to thereby align amplitudes of the respective target first and second phase currents with each other.
    Type: Application
    Filed: October 25, 2018
    Publication date: May 2, 2019
    Applicant: DENSO CORPORATION
    Inventor: Yasuaki AOKI
  • Publication number: 20180331645
    Abstract: A control apparatus for is a rotating electric machine applied to a control system including a power conversion circuit, a rotating electric machine, and a capacitor. The control apparatus selects two types of active voltage vectors that sandwich a command voltage vector that is applied to a rotating electric machine from a power conversion circuit and have a phase difference of 60 degrees therebetween. The control apparatus selects, of two types of active voltage vectors that sandwich the command voltage vector and have a phase difference of 120 degrees therebetween, one of two types of active voltage vectors that differs from the two types of active voltage vectors selected earlier, based on a driving state of the rotating electric machine. The control apparatus controls the power conversion apparatus to perform switching operations to control the rotating electric machine, based on the selected three types of active voltage vectors.
    Type: Application
    Filed: May 14, 2018
    Publication date: November 15, 2018
    Applicant: DENSO CORPORATION
    Inventors: Yasuaki AOKI, Shinji MAKITA
  • Publication number: 20170201201
    Abstract: In a current detection apparatus, an arm current detection unit detects each of at least first and second phase currents having respective amplitudes and flowing in a multiphase rotary electric machine based on a potential difference between input and output terminals of the corresponding one of first and second detection switches during the corresponding one of the first and second detection switches being on. A bus current detection unit detects each of at least bus-based first and second phase currents corresponding to the first and second phases of the multiphase rotary electric machine based on a current flowing through one of first and second buses. An amplitude correction unit corrects the first and second phase currents based on the bus-based first and second phase currents such that the amplitudes of the respective first and second phase currents match with each other.
    Type: Application
    Filed: December 29, 2016
    Publication date: July 13, 2017
    Applicant: DENSO CORPORATION
    Inventors: Yasuaki AOKI, Yosuke MATSUKI, Hideji YOSHIDA
  • Patent number: 9013137
    Abstract: In a system for driving an inverter, a superimposing element superimposes, on an output voltage of the inverter. The high-frequency voltage signal is correlated with a measured high-frequency component value of a current flowing in the rotary machine. A calculating element calculates a rotational angle of the rotary machine based on the measured high-frequency component value. A dead-time compensating element shifts a start edge and an end edge of an on duration for each of first and second switching elements of the inverter by a preset same time to compensate for an error due to dead time. A current manipulating element manipulates a current flowing in the rotary machine to maintain an accuracy of calculation of the rotational angle.
    Type: Grant
    Filed: February 28, 2012
    Date of Patent: April 21, 2015
    Assignee: Denso Corporation
    Inventors: Yasuaki Aoki, Hiroko Yoneshima, Tomoya Takahashi
  • Patent number: 9007795
    Abstract: The power conversion device includes a plurality of semiconductor modules, each having a main body section including a switching element therein. In a module unit, a positive module and a negative module are disposed such that main surfaces of the respective main body sections oppose each other. A positive terminal, a first intermediate terminal, a negative terminal, and a second intermediate terminal project in a Z direction perpendicular to X direction in which the positive module and the negative module oppose each other. A first vector V1 from the positive terminal towards the first intermediate terminal and a second vector V2 from the second intermediate terminal towards the negative terminal are configured such that these vector components V12 and V22 in a Y direction perpendicular to both the X and Z directions are opposite to each other.
    Type: Grant
    Filed: March 18, 2013
    Date of Patent: April 14, 2015
    Assignee: Denso Corporation
    Inventors: Tetsuya Matsuoka, Hiroyoshi Sawada, Makoto Okamura, Hiroshi Inamura, Yasuaki Aoki
  • Patent number: 8829829
    Abstract: In a system, a superimposing element sets a command value vector of a high-frequency voltage signal and superimposes the high-frequency voltage signal with the command value vector on an output voltage of an inverter. The high-frequency voltage signal has a frequency higher than an electrical angular frequency of a rotary machine. The command value vector is correlated with a measured high-frequency component value of a current signal flowing in the rotary machine. A calculating element calculates a rotational angle of the rotary machine based on the measured high-frequency component value of the current signal flowing in the rotary machine. A reducing element controls at least one of the inverter and a direct voltage power supply to reduce a difference due to the dead time between the command value vector and a vector of a high-frequency voltage signal to be actually superimposed on the output voltage of the inverter.
    Type: Grant
    Filed: February 14, 2012
    Date of Patent: September 9, 2014
    Assignee: Denso Corporation
    Inventors: Hiroko Yoneshima, Yasuaki Aoki, Hideji Yoshida
  • Publication number: 20130272046
    Abstract: The power conversion device includes a plurality of semiconductor modules, each having a main body section including a switching element therein. In a module unit, a positive module and a negative module are disposed such that main surfaces of the respective main body sections oppose each other. A positive terminal, a first intermediate terminal, a negative terminal, and a second intermediate terminal project in a Z direction perpendicular to X direction in which the positive module and the negative module oppose each other. A first vector V1 from the positive terminal towards the first intermediate terminal and a second vector V2 from the second intermediate terminal towards the negative terminal are configured such that these vector components V12 and V22 in a Y direction perpendicular are opposite to each other.
    Type: Application
    Filed: March 18, 2013
    Publication date: October 17, 2013
    Applicant: DENSO CORPORATION
    Inventors: Tetsuya MATSUOKA, Hiroyoshi SAWADA, Makoto OKAMURA, Hiroshi INAMURA, Yasuaki AOKI
  • Publication number: 20120217849
    Abstract: In a system for driving an inverter, a superimposing element superimposes, on an output voltage of the inverter. The high-frequency voltage signal is correlated with a measured high-frequency component value of a current flowing in the rotary machine. A calculating element calculates a rotational angle of the rotary machine based on the measured high-frequency component value. A dead-time compensating element shifts a start edge and an end edge of an on duration for each of first and second switching elements of the inverter by a preset same time to compensate for an error due to dead time. A current manipulating element manipulates a current flowing in the rotary machine to maintain an accuracy of calculation of the rotational angle.
    Type: Application
    Filed: February 28, 2012
    Publication date: August 30, 2012
    Applicant: DENSO CORPORATION
    Inventors: Yasuaki AOKI, Hiroko Yoneshima, Tomoya Takahashi
  • Publication number: 20120206077
    Abstract: In a system, a superimposing element sets a command value vector of a high-frequency voltage signal and superimposes the high-frequency voltage signal with the command value vector on an output voltage of an inverter. The high-frequency voltage signal has a frequency higher than an electrical angular frequency of a rotary machine. The command value vector is correlated with a measured high-frequency component value of a current signal flowing in the rotary machine. A calculating element calculates a rotational angle of the rotary machine based on the measured high-frequency component value of the current signal flowing in the rotary machine. A reducing element controls at least one of the inverter and a direct voltage power supply to reduce a difference due to the dead time between the command value vector and a vector of a high-frequency voltage signal to be actually superimposed on the output voltage of the inverter.
    Type: Application
    Filed: February 14, 2012
    Publication date: August 16, 2012
    Applicant: DENSO CORPORATION
    Inventors: Hiroko YONESHIMA, Yasuaki Aoki, Hideji Yoshida
  • Patent number: 8106622
    Abstract: A control system aims at converting, via a switching circuit, a direct current voltage into an alternating current voltage to be applied to multiphase windings of a multiphase rotary machine to thereby control rotation of the multiphase rotary machine. In the control system, a command voltage determiner determines a command voltage value for an alternating current voltage to be applied to the multiphase windings based on a zero crossing of a line-to-line current and a zero crossing of the amount of change in the line-to-line current. A driving unit drives the switching circuit on and off based on the determined command voltage value to thereby modulate the direct current voltage to the alternating current voltage to be applied to the multiphase windings.
    Type: Grant
    Filed: April 4, 2008
    Date of Patent: January 31, 2012
    Assignee: Denso Corporation
    Inventors: Yasuaki Aoki, Hideji Yoshida
  • Patent number: 7514896
    Abstract: In a method of estimating a magnetic pole position in a synchronous motor, an alternating current voltage having ?- and ?-axes components in an ?? coordinates system representing a two-phase alternating current coordinates system is applied to the motor, and ?- and ?-axes components of an alternating current are detected from the motor. A wave height of the alternating current changing with time is approximated to a wave height not depending on time, so that a differentiated value of the wave height with respect to time is substantially set at zero. An induced voltage of the motor is calculated from the components of the alternating current voltage and the components of the alternating current. The magnetic pole position is estimated from the induced voltage.
    Type: Grant
    Filed: August 17, 2006
    Date of Patent: April 7, 2009
    Assignee: Denso Corporation
    Inventors: Akihiro Imura, Yasuaki Aoki
  • Publication number: 20080246426
    Abstract: A control system aims at converting, via a switching circuit, a direct current voltage into an alternating current voltage to be applied to multiphase windings of a multiphase rotary machine to thereby control rotation of the multiphase rotary machine. In the control system, a command voltage determiner determines a command voltage value for an alternating current voltage to be applied to the multiphase windings based on a zero crossing of a line-to-line current and a zero crossing of the amount of change in the line-to-line current. A driving unit drives the switching circuit on and off based on the determined command voltage value to thereby modulate the direct current voltage to the alternating current voltage to be applied to the multiphase windings.
    Type: Application
    Filed: April 4, 2008
    Publication date: October 9, 2008
    Applicant: DENSO CORPORATION
    Inventors: Yasuaki Aoki, Hideji Yoshida
  • Publication number: 20070296371
    Abstract: The position sensorless control apparatus is for controlling a synchronous motor having a permanent magnet rotor structure by generating fundamental voltage vectors used to designate on/off states of switching devices included in an inverter circuit thereof. The position sensorless control apparatus includes a current change rate detecting section detecting, as a current change rate, a change rate of a phase current flowing through the synchronous motor when a predetermined one of the fundamental voltage vectors is being generated, and a rotor magnetic pole position estimating section estimating, as a rotor magnetic pole position, a rotational position of a rotor of the synchronous motor on the basis of the current change rate detected by the current change rate detecting section.
    Type: Application
    Filed: June 5, 2007
    Publication date: December 27, 2007
    Applicant: DENSO CORPORATION
    Inventor: Yasuaki Aoki
  • Publication number: 20070069681
    Abstract: In a method of estimating a magnetic pole position in a synchronous motor, an alternating current voltage having ?- and ?-axes components in an ?? coordinates system representing a two-phase alternating current coordinates system is applied to the motor, and ?- and ?-axes components of an alternating current are detected from the motor. A wave height of the alternating current changing with time is approximated to a wave height not depending on time, so that a differentiated value of the wave height with respect to time is substantially set at zero. An induced voltage of the motor is calculated from the components of the alternating current voltage and the components of the alternating current. The magnetic pole position is estimated from the induced voltage.
    Type: Application
    Filed: August 17, 2006
    Publication date: March 29, 2007
    Applicant: DENSO CORPORATION
    Inventors: Akihiro Imura, Yasuaki Aoki
  • Patent number: 7026782
    Abstract: An apparatus is provided for controlling a synchronous motor. The apparatus comprises a first calculator calculating a voltage characteristic showing a characteristic of voltages to be applied to armature coils of a stator and a producer producing a command signal to provide the armature coils with the phase currents on the basis of the voltage characteristic. The apparatus still comprises a current detector detecting a signal depending on an amplitude of at least one of the phase currents, a second calculator calculating a rate of changes in a current amount indicating amplitudes of the phase currents, by using the signal from the current detector, and a feed-back member feed-backing the rate of changes in the current amount into the calculation of the voltage characteristic.
    Type: Grant
    Filed: July 14, 2005
    Date of Patent: April 11, 2006
    Assignee: Denso Corporation
    Inventors: Yasuaki Aoki, Hideji Yoshida, Hiroshi Amano
  • Publication number: 20060012329
    Abstract: An apparatus is provided for controlling a synchronous motor. The apparatus comprises a first calculator calculating a voltage characteristic showing a characteristic of voltages to be applied to armature coils of a stator and a producer producing a command signal to provide the armature coils with the phase currents on the basis of the voltage characteristic. The apparatus still comprises a current detector detecting a signal depending on an amplitude of at least one of the phase currents, a second calculator calculating a rate of changes in a current amount indicating amplitudes of the phase currents, by using the signal from the current detector, and a feed-back member feed-backing the rate of changes in the current amount into the calculation of the voltage characteristic.
    Type: Application
    Filed: July 14, 2005
    Publication date: January 19, 2006
    Applicant: DENSO CORPORATION
    Inventors: Yasuaki Aoki, Hideji Yoshida, Hiroshi Amano