Patents by Inventor Ken Iwatsuki

Ken Iwatsuki 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: 9998052
    Abstract: The magnetic pole position of a rotary electric machine is electrically derived accurately by reducing a voltage error due to a dead time while suppressing the influence on the operation efficiency of the rotary electric machine. A control device performs dead-time compensation, and performs current feedback control in a d-q-axis vector coordinate system using a magnetic pole position computed on the basis of an induced voltage produced by rotation of a rotor or on the basis of a response component to a high-frequency observation signal applied to the rotary electric machine. In the case where the rotary electric machine is controlled by deciding current commands Id*, Iq* in the d-q-axis vector coordinate system, the rotary electric machine control device controls the rotary electric machine such that the magnitude of an armature current Ia becomes equal to or more than a lower-limit current Ia_min prescribed in advance.
    Type: Grant
    Filed: March 30, 2015
    Date of Patent: June 12, 2018
    Assignee: AISIN AW CO., LTD.
    Inventors: Arinori Shimada, Masashi Miyazaki, Subrata Saha, Keisuke Nishimura, Ken Iwatsuki
  • Patent number: 9634589
    Abstract: Both downsizing of an apparatus as a whole and reduction in a product cost are attained. The preferred embodiments relate to a drive device including an alternating-current rotary electric machine, an inverter, and a case. The inverter is fixed to the case. The case and the inverter are disposed in a driving force source room. The inverter includes shunt resistors to detect currents flowing in respective switching element units for corresponding phases.
    Type: Grant
    Filed: March 19, 2014
    Date of Patent: April 25, 2017
    Assignee: AISIN AW CO., LTD.
    Inventors: Keiko Nakao, Ken Iwatsuki
  • Patent number: 9634590
    Abstract: A drive device that includes an alternating-current rotary electric machine in which currents of a plurality of phases flow; an inverter that includes switching element units for respective phases corresponding to the respective phases, and that is connected between a direct-current power supply and the alternating-current rotary electric machine and performs conversion between a direct current and an alternating current; and shunt resistors that detect currents flowing in the respective switching element units for the corresponding phases between the direct-current power supply and the switching element units for the respective phases.
    Type: Grant
    Filed: March 19, 2014
    Date of Patent: April 25, 2017
    Assignee: AISIN AW CO., LTD.
    Inventors: Keiko Nakao, Ken Iwatsuki
  • Publication number: 20170110999
    Abstract: The magnetic pole position of a rotary electric machine is electrically derived accurately by reducing a voltage error due to a dead time while suppressing the influence on the operation efficiency of the rotary electric machine. A control device performs dead-time compensation, and performs current feedback control in a d-q-axis vector coordinate system using a magnetic pole position computed on the basis of an induced voltage produced by rotation of a rotor or on the basis of a response component to a high-frequency observation signal applied to the rotary electric machine. In the case where the rotary electric machine is controlled by deciding current commands Id*, Iq* in the d-q-axis vector coordinate system, the rotary electric machine control device controls the rotary electric machine such that the magnitude of an armature current Ia becomes equal to or more than a lower-limit current Ia_min prescribed in advance.
    Type: Application
    Filed: March 30, 2015
    Publication date: April 20, 2017
    Applicant: AISIN AW CO., LTD.
    Inventors: Arinori SHIMADA, Masashi MIYAZAKI, Subrata SAHA, Keisuke NISHIMURA, Ken IWATSUKI
  • Patent number: 9531309
    Abstract: A drive device that includes a current sensor that detects a current flowing in the wheel driving rotary electric machine; and shunt resistors that detect currents flowing in the respective second switching element units for the corresponding phases between the direct-current power supply and the second switching element units for the respective phases, wherein a ratio of a period during which current detection can be performed by the current sensor to a control period of the first inverter is higher than a ratio of a period during which current detection can be performed by the shunt resistors to a control period of the second inverter.
    Type: Grant
    Filed: March 19, 2014
    Date of Patent: December 27, 2016
    Assignee: AISIN AW CO., LTD.
    Inventors: Keiko Nakao, Ken Iwatsuki
  • Publication number: 20160156292
    Abstract: Both downsizing of an apparatus as a whole and reduction in a product cost are attained. The preferred embodiments relate to a drive device including an alternating-current rotary electric machine, an inverter, and a case. The inverter is fixed to the case. The case and the inverter are disposed in a driving force source room. The inverter includes shunt resistors to detect currents flowing in respective switching element units for corresponding phases.
    Type: Application
    Filed: March 19, 2014
    Publication date: June 2, 2016
    Applicant: AISIN AW CO., LTD.
    Inventors: Keiko NAKAO, Ken IWATSUKI
  • Publication number: 20160134214
    Abstract: A drive device that includes an alternating-current rotary electric machine in which currents of a plurality of phases flow; an inverter that includes switching element units for respective phases corresponding to the respective phases, and that is connected between a direct-current power supply and the alternating-current rotary electric machine and performs conversion between a direct current and an alternating current; and shunt resistors that detect currents flowing in the respective switching element units for the corresponding phases between the direct-current power supply and the switching element units for the respective phases
    Type: Application
    Filed: March 19, 2014
    Publication date: May 12, 2016
    Applicant: AISIN AW CO., LTD.
    Inventors: Keiko Nakao, Ken Iwatsuki
  • Publication number: 20160126882
    Abstract: A drive device that includes a current sensor that detects a current flowing in the wheel driving rotary electric machine; and shunt resistors that detect currents flowing in the respective second switching element units for the corresponding phases between the direct-current power supply and the second switching element units for the respective phases, wherein a ratio of a period during which current detection can be performed by the current sensor to a control period of the first inverter is higher than a ratio of a period during which current detection can be performed by the shunt resistors to a control period of the second inverter.
    Type: Application
    Filed: March 19, 2014
    Publication date: May 5, 2016
    Applicant: AISIN AW CO., LTD.
    Inventors: Keiko NAKAO, Ken IWATSUKI
  • Patent number: 9018870
    Abstract: A control device for a rotating electrical machine, which is able to reduce a tracking delay of an actual output torque and actual currents with respect to a fluctuating torque command and fluctuating current commands and to reduce steady state deviations, is obtained. The control device includes a torque current computing unit; an actual current computing unit; a current feedback control unit; and a voltage control unit that controls voltages on the basis of the two-phase voltage commands. The torque command includes a fluctuation cancellation torque command for cancelling transmission torque fluctuations transmitted from the internal combustion engine, and the current feedback control unit includes a harmonic controller that calculates the two-phase voltage commands by using a characteristic of a transfer function corresponding to a periodic function of a frequency of the transmission torque fluctuations.
    Type: Grant
    Filed: March 23, 2012
    Date of Patent: April 28, 2015
    Assignee: Aisin AW Co., Ltd.
    Inventors: Hirokazu Kobayashi, Arinori Shimada, Takeshi Aoki, Subrata Saha, Ken Iwatsuki
  • Patent number: 8624534
    Abstract: A control device for an electric motor driving apparatus, configured with a switching control unit that performs rectangular wave control in which a plurality of switching elements provided in a direct current-alternating current conversion unit are ON/OFF-controlled to output rectangular wave-shaped voltages of a plurality of phases. System voltage varies during execution of the rectangular wave control, the switching control unit performs rectangular wave width adjustment control to set ON/OFF timings of the plurality of switching elements on the basis of a rate of change of the system voltage such that time-integrated values of the rectangular wave-shaped voltages of the respective phases within a control period set at a length corresponding to an integral multiple of a single electrical angle period are substantially identical among the respective phases.
    Type: Grant
    Filed: June 22, 2010
    Date of Patent: January 7, 2014
    Assignee: Aisin AW Co., Ltd.
    Inventors: Ken Iwatsuki, Zhiqian Chen
  • Publication number: 20130307449
    Abstract: A control device for a rotating electrical machine, which is able to reduce a tracking delay of an actual output torque and actual currents with respect to a fluctuating torque command and fluctuating current commands and to reduce steady state deviations, is obtained. The control device includes a torque current computing unit; an actual current computing unit; a current feedback control unit; and a voltage control unit that controls voltages on the basis of the two-phase voltage commands. The torque command includes a fluctuation cancellation torque command for cancelling transmission torque fluctuations transmitted from the internal combustion engine, and the current feedback control unit includes a harmonic controller that calculates the two-phase voltage commands by using a characteristic of a transfer function corresponding to a periodic function of a frequency of the transmission torque fluctuations.
    Type: Application
    Filed: March 23, 2012
    Publication date: November 21, 2013
    Applicant: AISIN AW CO., LTD.
    Inventors: Hirokazu Kobayashi, Arinori Shimada, Takeshi Aoki, Subrata Saha, Ken Iwatsuki
  • Patent number: 8497645
    Abstract: A control device that controls an electric motor drive device is configured with a current control portion that determines a voltage command value, a voltage control portion that generates a switching control signal, and a current control period determining portion. The control device is also configured with a voltage control period determining portion that determines a voltage control period, and a control period setting portion. In the control device, the current control period determining portion determines, according to a target torque, the current control period as a value that increases continuously or stepwise as the target torque decreases. Furthermore, the voltage control period determining portion determines, according to a rotating speed, the voltage control period as a value that increases continuously or stepwise as the rotating speed decreases.
    Type: Grant
    Filed: October 22, 2010
    Date of Patent: July 30, 2013
    Assignee: Aisin AW Co., Ltd.
    Inventors: Arinori Shimada, Subrata Saha, Ken Iwatsuki
  • Publication number: 20130187583
    Abstract: A control device for an electric motor driving apparatus, configured with a switching control unit that performs rectangular wave control in which a plurality of switching elements provided in a direct current-alternating current conversion unit are ON/OFF-controlled to output rectangular wave-shaped voltages of a plurality of phases. System voltage varies during execution of the rectangular wave control, the switching control unit performs rectangular wave width adjustment control to set ON/OFF timings of the plurality of switching elements on the basis of a rate of change of the system voltage such that time-integrated values of the rectangular wave-shaped voltages of the respective phases within a control period set at a length corresponding to an integral multiple of a single electrical angle period are substantially identical among the respective phases.
    Type: Application
    Filed: June 22, 2010
    Publication date: July 25, 2013
    Applicant: AISIN AW CO., LTD.
    Inventors: Ken Iwatsuki, Zhiqian Chen
  • Patent number: 8390223
    Abstract: A control device that controls an electric motor drive device. The control device is configured with a first voltage control section that derives a modulation rate representing a ratio of an effective value of the voltage command values to the DC voltage and a voltage command phase. A second voltage control section generates a control signal for controlling the DC/AC conversion section on the basis of the modulation rate, the voltage command phase, and a magnetic pole position representing a rotational angle of a rotator of the AC electric motor. A computation cycle of the first voltage control section is set to be longer than a computation cycle of the second voltage control section.
    Type: Grant
    Filed: August 12, 2010
    Date of Patent: March 5, 2013
    Assignee: Aisin AW Co., Ltd.
    Inventors: Mitsuru Nakamura, Arinori Shimada, Subrata Saha, Ken Iwatsuki, Zhiqian Chen
  • Publication number: 20120249024
    Abstract: An electric motor control device includes a mode in which an inverter is controlled by a current phase of an armature current in a 2-axis orthogonal vector space, a vector being obtained by synthesizing a field and a drive current along two axes defining the vector space; a high-loss control section that, when extra power results from charging a power storage device, varies the field current in accordance with the extra power to increase the armature current while maintaining torque of an AC electric motor; and the high-loss control section varies the field current to one of a field weakening and a field intensifying side of the electric motor, which results in the higher power loss within a range in which the armature current can be output in the vector space and which is determined based on the DC power source voltage and a rotational speed of the electric motor.
    Type: Application
    Filed: March 23, 2012
    Publication date: October 4, 2012
    Applicant: AISIN AW CO., LTD.
    Inventors: Subrata SAHA, Ken IWATSUKI
  • Patent number: 8278865
    Abstract: A control device that controls a plurality of inverters respectively provided corresponding to a plurality of alternating-current electric motors so as to control the plurality of alternating-current electric motors by current feedback. The control device comprises a carrier frequency setting unit that individually selects and sets one of a plurality of carrier frequencies, each of which is a frequency of a carrier for generating switching control signals for the inverter based on a pulse width modulation method, for each of the plurality of inverters, and a switching timing table that specifies a switching timing serving as a permissible timing of switching to a different carrier frequency pair from each of a plurality of carrier frequency pairs each of which is composed of a combination of the carrier frequencies set for each of the plurality of inverters.
    Type: Grant
    Filed: August 31, 2010
    Date of Patent: October 2, 2012
    Assignee: Aisin AW Co., Ltd.
    Inventors: Arinori Shimada, Mitsuru Nakamura, Subrata Saha, Ken Iwatsuki
  • Patent number: 8269446
    Abstract: When an electric vehicle outputs a torque instruction, firstly, a request torque is acquired and a judged whether the acquired request torque is positive or negative. Regardless of the sign of the request torque, it is judged whether the eco-switch is ON. If the request torque has a positive sign and the eco-switch is OFF, a map A is selected. If the eco-switch is ON, a map B which limits the maximum torque to a low value for the map A is selected. If the request torque has a negative sign, a map C is selected regardless of the eco-switch ON/OFF state and the maximum torque is not limited.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: September 18, 2012
    Assignees: Toyota Jidosha Kabushiki Kaisha, Aisin AW Co., Ltd.
    Inventors: Masayoshi Suhama, Hideto Hanada, Masaki Okamura, Hiroaki Kioka, Ken Iwatsuki
  • Patent number: 8232753
    Abstract: A electric motor drive apparatus comprising a voltage control unit performing voltage control processing that determines alternating-current voltage command values serving as command values of the alternating-current voltages to be supplied to the alternating-current electric motor and generates switching control signals for the inverter; and a control mode selection unit selecting a synchronous control mode in which a cycle of electric angle of the alternating-current electric motor is synchronized with a switching cycle of the inverter, or an asynchronous control mode in which the cycles are not synchronized with each other. Current detection processing is performed to detect currents flowing in coils of the alternating-current electric motor in every standard calculation cycle that is set to a half of a cycle of the carrier.
    Type: Grant
    Filed: August 31, 2010
    Date of Patent: July 31, 2012
    Assignee: Aisin AW Co., Ltd.
    Inventors: Arinori Shimada, Mitsuru Nakamura, Subrata Saha, Ken Iwatsuki
  • Publication number: 20120032620
    Abstract: A control device that controls for an electric motor drive device including a DC/AC conversion section that converts a DC voltage into an AC voltage to supply the AC voltage to an AC electric motor. The control device is configured with a computation cycle setting section that sets a computation cycle of the control signal generation section to a first cycle, which is N times (N is an integer of 1 or more) a reference computation cycle that is set to half a carrier cycle, and that sets a computation cycle of the voltage command value determination section to a second cycle, which is M times (M is an integer of 2 or more) the first cycle, in the case where the control mode determined by the control mode determination section is the pulse width modulation control mode.
    Type: Application
    Filed: June 28, 2011
    Publication date: February 9, 2012
    Applicant: AISIN AW CO., LTD.
    Inventors: Arinori SHIMADA, Subrata SAHA, Ken IWATSUKI
  • Patent number: 8093843
    Abstract: By the vehicle controller of the present invention, when the economy mode is selected by a driver, boosting by a converter is limited and output torque of a motor is limited. Even in the economy mode, however, if the driver requests large torque, either the limit on boosting or the limit on output torque is cancelled. As a result, a vehicle controller for a vehicle including a battery, a converter boosting/lowering the battery voltage and a motor operating with the power from the converter is provided, by which unnecessary power consumption is reduced and the torque requested by the driver can be generated.
    Type: Grant
    Filed: May 19, 2008
    Date of Patent: January 10, 2012
    Assignees: Toyota Jidosha Kabushiki Kaisha, Aisin Aw Co., Ltd.
    Inventors: Masaki Okamura, Hideto Hanada, Masayoshi Suhama, Yuki Sugiyama, Ken Iwatsuki