Patents by Inventor Tatsuki Kashihara

Tatsuki Kashihara 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: 20220320995
    Abstract: An inverter device is provided which is capable of effectively eliminating or suppressing common mode noise in consideration of the influence of a dead time by using the function of a PWM signal generating unit. A control device 21 includes a phase voltage command calculating unit 33 which calculates three-phase modulation voltage command values for generating voltages to be applied to respective phases of a motor 8, and a PWM signal generating unit 36 which, based on the three-phase modulation voltage command values and a single carrier signal, generates a PWM signal to PWM-control an inverter circuit 28. The PWM signal generating unit 36 corrects the three-phase modulation voltage command values output by the phase voltage command calculating unit 33 to thereby cancel a change in the phase voltage applied to the motor 8 by a change in another phase voltage.
    Type: Application
    Filed: July 21, 2020
    Publication date: October 6, 2022
    Applicant: SANDEN HOLDINGS CORPORATION
    Inventor: Tatsuki KASHIHARA
  • Patent number: 11283386
    Abstract: There is provided a power conversion device capable of eliminating a disadvantage of a sharp temperature rise in a switching element by using a discontinuous modulation method. The power conversion device includes a phase voltage command operation unit 33 which calculates a sinusoidal modulation voltage command value to be applied to a motor 8, an inter-line modulation operation unit 34 which, based on the sinusoidal modulation voltage command value, calculates a discontinuous modulation voltage command value for allowing an ON/OFF state of a switching element of one phase of a three-phase inverter circuit 28 to be fixed, and modulating ON/OFF states of switching elements of other two phases, and a PWM signal generation unit 36. The inter-line modulation operation unit sets a switching density of the switching element of at least one phase to a value different from that of the other phase.
    Type: Grant
    Filed: November 15, 2018
    Date of Patent: March 22, 2022
    Assignee: SANDEN HOLDINGS CORPORATION
    Inventors: Tatsuki Kashihara, Takahiro Saigusa
  • Patent number: 11223296
    Abstract: There is provided a power conversion device capable of effectively reducing a surge voltage generated by a parasitic inductance of a circuit. The power conversion device 1 is configured to operate a motor 8 driving a compression mechanism 7 of an electric compressor 16 by means of a three-phase inverter circuit 28 having a plurality of switching elements 18A to 18F. The power conversion device calculates a surge voltage value of each phase from a parasitic inductance of the circuit and phase currents iu, iv, and iw of the motor 8 to derive a phase in which the surge voltage value becomes maximum, and suppresses the switching of the switching elements 18A-18F of the phase having the maximum surge voltage value by a discontinuous modulation method.
    Type: Grant
    Filed: February 5, 2019
    Date of Patent: January 11, 2022
    Assignee: SANDEN HOLDINGS CORPORATION
    Inventor: Tatsuki Kashihara
  • Publication number: 20200403530
    Abstract: There is provided a power conversion device capable of effectively reducing a surge voltage generated by a parasitic inductance of a circuit. The power conversion device 1 is configured to operate a motor 8 driving a compression mechanism 7 of an electric compressor 16 by means of a three-phase inverter circuit 28 having a plurality of switching elements 18A to 18F. The power conversion device calculates a surge voltage value of each phase from a parasitic inductance of the circuit and phase currents iu, iv, and iw of the motor 8 to derive a phase in which the surge voltage value becomes maximum, and suppresses the switching of the switching elements 18A-18F of the phase having the maximum surge voltage value by a discontinuous modulation method.
    Type: Application
    Filed: February 5, 2019
    Publication date: December 24, 2020
    Inventor: Tatsuki KASHIHARA
  • Publication number: 20200389118
    Abstract: There is provided a power conversion device capable of eliminating a disadvantage of a sharp temperature rise in a switching element by using a discontinuous modulation method. The power conversion device includes a phase voltage command operation unit 33 which calculates a sinusoidal modulation voltage command value to be applied to a motor 8, an inter-line modulation operation unit 34 which, based on the sinusoidal modulation voltage command value, calculates a discontinuous modulation voltage command value for allowing an ON/OFF state of a switching element of one phase of a three-phase inverter circuit 28 to be fixed, and modulating ON/OFF states of switching elements of other two phases, and a PWM signal generation unit 36. The inter-line modulation operation unit sets a switching density of the switching element of at least one phase to a value different from that of the other phase.
    Type: Application
    Filed: November 15, 2018
    Publication date: December 10, 2020
    Inventors: Tatsuki KASHIHARA, Takahiro SAIGUSA
  • Patent number: 9219434
    Abstract: A motor control device according to the present invention includes: a boost converter circuit 30 that boosts a direct-current voltage; an inverter 40 that generates a drive pulse for a motor 50 from the direct-current voltage of the boost converter circuit 30; and a control section 60 that presets a set value Id_hold obtained by multiplying a set value Id_max by an intermediate current threshold coefficient ?, controls a pulse width of the drive pulse of the inverter 40 based on a speed deviation, controls a d-axis current in the motor 50 based on the speed deviation so that the pulse width of the drive pulse of the inverter 40 does not exceed a threshold value, and controls the direct-current voltage of the boost converter circuit 30 based on the speed deviation so that the d-axis current in the motor 50 does not exceed the set value Id_hold.
    Type: Grant
    Filed: February 21, 2013
    Date of Patent: December 22, 2015
    Assignee: SANDEN CORPORATION
    Inventors: Tatsuki Kashihara, Hiroshi Yoshida, Kouji Kobayashi
  • Publication number: 20150002058
    Abstract: A motor control device according to the present invention includes: a boost converter circuit 30 that boosts a direct-current voltage; an inverter 40 that generates a drive pulse for a motor 50 from the direct-current voltage of the boost converter circuit 30; and a control section 60 that presets a set value Id_hold obtained by multiplying a set value Id_max by an intermediate current threshold coefficient ?, controls a pulse width of the drive pulse of the inverter 40 based on a speed deviation, controls a d-axis current in the motor 50 based on the speed deviation so that the pulse width of the drive pulse of the inverter 40 does not exceed a threshold value, and controls the direct-current voltage of the boost converter circuit 30 based on the speed deviation so that the d-axis current in the motor 50 does not exceed the set value Id_hold.
    Type: Application
    Filed: February 21, 2013
    Publication date: January 1, 2015
    Applicant: SANDEN CORPORATION
    Inventors: Tatsuki Kashihara, Hiroshi Yoshida, Kouji Kobayashi
  • Publication number: 20110109169
    Abstract: An antenna unit includes a plurality of loop antennas; an impedance matching circuit common to the loop antennas; a switching circuit that switches high frequency connection between the impedance matching circuit and the loop antenna; and an antenna control circuit that controls to connect only one loop antenna among the loop antennas in a high frequency manner on the basis of a control signal from a reader.
    Type: Application
    Filed: July 6, 2009
    Publication date: May 12, 2011
    Applicant: Sanden Corporation
    Inventors: Gaku Shimamoto, Yuuji Kuwako, Naoto Matsumoto, Masaru Tabata, Masaaki Satou, Tatsuki Kashihara