Patents by Inventor Tomotake SASAKI

Tomotake SASAKI 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: 9774249
    Abstract: A power supply apparatus includes: an inductor to which an input voltage is applied; a switching element that switches a current flowing to the inductor on and off so as to cause an induced voltage to be generated; an electrolytic capacitor that smoothes the induced voltage and outputs the voltage to a load; and a control circuit that controls the switching element, wherein the control circuit outputs a second switching control signal obtained by superimposing a degradation detection-purpose signal for detecting degradation of the electrolytic capacitor on a first control signal, detects an output voltage output by switching performed by the switching element controlled by the second control signal, and estimates the degradation of the electrolytic capacitor by using the output voltage detected, a duty cycle of the first control signal, and a frequency component of the degradation detection-purpose signal contained in the output voltage detected.
    Type: Grant
    Filed: June 23, 2015
    Date of Patent: September 26, 2017
    Assignee: FUJITSU LIMITED
    Inventors: Yoshinobu Matsui, Hisato Hosoyama, Tomotake Sasaki
  • Patent number: 9742284
    Abstract: A power circuit includes: first and second switching circuits coupled in parallel between an input terminal and an output terminal; a control signal generator that performs an ON/OFF control of the first and second switching circuits individually and generates a first control signal and a second control signal having different phases; a frequency converter that converts a frequency of the first control signal after converting a frequency of the second control signal; and a phase shifter that shifts the phase of the second control signal when a first interrupt is introduced as the first control signal is turned ON after the frequency converter has converted the frequency of the second control signal.
    Type: Grant
    Filed: September 18, 2015
    Date of Patent: August 22, 2017
    Assignee: FUJITSU LIMITED
    Inventors: Hisato Hosoyama, Tomotake Sasaki, Yu Yonezawa
  • Patent number: 9733986
    Abstract: A computer system includes plural servers in which virtual machines are arranged; plural power supply apparatuses that supply electric power to the servers; and a control apparatus that controls arrangement of the virtual machines in the servers. The control apparatus solves an integer programming problem whose objective function is total power consumption by the servers and by the power supply apparatuses, the total power consumption being described as a function of the arrangement of the virtual machines; and arranges the virtual machines based on a solution of the integer programming problem.
    Type: Grant
    Filed: March 24, 2014
    Date of Patent: August 15, 2017
    Assignee: FUJITSU LIMITED
    Inventors: Tomotake Sasaki, Yuichi Sato, Hiroki Kobayashi, Sachio Kobayashi
  • Publication number: 20170099003
    Abstract: A control method for a switching power supply circuit, the control method causing a processor to execute a process, the process includes: calculating a differential value between an output voltage of the switching power supply circuit and a target voltage; multiplying the differential value by a first coefficient to calculate a correction value; correcting a first detection value of an output current of the switching power supply circuit, which is detected by a current transformer circuit, based on the correction value, to generate a second detection value; comparing the second detection value with a threshold current value to determine whether or not an overcurrent has occurred; and reducing, when it is determined that the overcurrent has occurred, the output voltage of the switching power supply circuit.
    Type: Application
    Filed: September 23, 2016
    Publication date: April 6, 2017
    Applicant: FUJITSU LIMITED
    Inventors: Yu Yonezawa, Tomotake Sasaki, Hisato HOSOYAMA, YOSHIYASU NAKASHIMA
  • Patent number: 9614401
    Abstract: A control server according to an embodiment sorts a plurality of notebook PCs into a plurality of groups so that the total value of the remaining energy is a value similar to the total value of the remaining energy of the rechargeable batteries of a plurality of notebook PCs included in a different group. The control server according to the embodiment performs local search individually on the sorted groups, and generates a control plan for the individual notebook PCs.
    Type: Grant
    Filed: February 28, 2014
    Date of Patent: April 4, 2017
    Assignees: FUJITSU LIMITED, THE UNIVERSITY OF TOKYO
    Inventors: Hitoshi Yanami, Hidenao Iwane, Tomotake Sasaki, Hirokazu Anai, Junji Kaneko, Shinji Hara, Suguru Fujita
  • Patent number: 9590512
    Abstract: A PFC circuit generates substantially sinusoidal current that is in-phase with AC input voltage to compensate for a power factor. A DC-DC converter converts the voltage of a signal outputted from the PFC circuit to determined voltage. A current change detection section detects an amount of change in current outputted from the DC-DC converter, compares the detected amount of change in current with a threshold set in advance, and if the detected amount of change in current is larger than the threshold, outputs a gain switching signal for raising the gain of voltage outputted from the PFC circuit. The current change detection section outputs a voltage control signal for raising the voltage outputted from the PFC circuit to a determined value. A voltage setting section sets the voltage outputted from the PFC circuit to the determined value on the basis of the voltage control signal.
    Type: Grant
    Filed: November 4, 2014
    Date of Patent: March 7, 2017
    Assignee: FUJITSU LIMITED
    Inventors: Yu Yonezawa, Tomotake Sasaki, Yoshinobu Matsui, Yoshiyasu Nakashima
  • Publication number: 20160291090
    Abstract: A control scheme creation method according to an embodiment includes executing, on a computer, processing of calculation of the amount of stored or released energy of each of a plurality of energy storage devices for each of a plurality of periods based on estimation value information on the amount of energy consumption within a target area and based on remaining amount information representing the amount of remaining energy of each of the plurality of energy storage devices. Furthermore, the control scheme creation method includes executing, on the computer, processing of determination of storage timing or release timing for the energy storage device for each of the periods based on the calculated amount of stored or released energy.
    Type: Application
    Filed: March 4, 2016
    Publication date: October 6, 2016
    Applicants: FUJITSU LIMITED, THE UNIVERSITY OF TOKYO
    Inventors: Tomotake Sasaki, Hitoshi Yanami, Junji Kaneko, Shinji Hara
  • Patent number: 9438107
    Abstract: A control device includes: a power supply circuit that controls output voltage using a switching element; a generation unit that generates a reference signal on the basis of the output voltage from the power supply circuit; a PWM unit that generates a PWM signal that is output to the switching element by comparing the reference signal with a carrier signal; and a switching unit that switches a frequency of the carrier signal by changing amplitude of the carrier signal, wherein the generation unit generates the reference signal on the basis of the frequency.
    Type: Grant
    Filed: December 3, 2013
    Date of Patent: September 6, 2016
    Assignee: FUJITSU LIMITED
    Inventors: Tomotake Sasaki, Tsugito Maruyama, Yu Yonezawa, Yoshiyasu Nakashima
  • Publication number: 20160154453
    Abstract: A power-supply control apparatus includes a processor that executes a process. The process includes calculating, for a first time period, a first predictive value of total power consumption by the power-supply control apparatus and one or more other power-supply control apparatuses to which power is supplied from a power supply; and determining whether to allow a storage battery to be charged in the first time period based on the first predictive value for the first time period and previous information that is related to the first predictive value and obtained in a second time period before the first time period.
    Type: Application
    Filed: October 26, 2015
    Publication date: June 2, 2016
    Applicants: FUJITSU LIMITED, The University of Tokyo
    Inventors: Tomotake SASAKI, Hitoshi YANAMI, Junji KANEKO, Shinji HARA
  • Publication number: 20160105114
    Abstract: A power circuit includes: first and second switching circuits coupled in parallel between an input terminal and an output terminal; a control signal generator that performs an ON/OFF control of the first and second switching circuits individually and generates a first control signal and a second control signal having different phases; a frequency converter that converts a frequency of the first control signal after converting a frequency of the second control signal; and a phase shifter that shifts the phase of the second control signal when a first interrupt is introduced as the first control signal is turned ON after the frequency converter has converted the frequency of the second control signal.
    Type: Application
    Filed: September 18, 2015
    Publication date: April 14, 2016
    Applicant: Fujitsu Limited
    Inventors: Hisato HOSOYAMA, Tomotake Sasaki, Yu Yonezawa
  • Publication number: 20160087555
    Abstract: An RCP (Rapid Control Prototyping) system for controlling a power supply apparatus, the RCP system includes: a computer; an MPU; and a bridge configured to connect the computer and the MPU and transfer data between the computer and the MPU using DMA, wherein the MPU is configured to generate an AD value from a signal of the power supply apparatus according to a switching period of the power supply apparatus, instruct to transfer the generated AD value to the computer using DMA via the bridge, and control the power supply apparatus according to a compensation value transferred using DMA via the bridge, and the computer is configured to instruct to transfer the compensation value calculated based on the AD value transferred through the last DMA to the MPU using DMA via the bridge and calculate the compensation value based on the AD value newly transferred using DMA.
    Type: Application
    Filed: August 27, 2015
    Publication date: March 24, 2016
    Applicant: FUJITSU LIMITED
    Inventors: Hisato HOSOYAMA, Yu Yonezawa, Tomotake Sasaki
  • Patent number: 9244714
    Abstract: A computer system includes servers having virtual machines arranged therein; a noise source in each among the servers, the noise source emitting sound when the server is operated; and a controller that controls arrangement of the virtual machines in the servers. The controller solves an integer programming problem having an objective function representing a noise contribution described as any one among a function of virtual machine arrangement and a function of a job assignment count and indicating an extent of contribution of the sound emitted from the noise source to a noise volume at an evaluation point, by executing software for solving the integer programming problem on a processor, and based on a solution to the integer programming problem, causes the processor to arrange the virtual machines in the servers via an interface for the servers.
    Type: Grant
    Filed: August 5, 2014
    Date of Patent: January 26, 2016
    Assignee: FUJITSU LIMITED
    Inventors: Hideki Abe, Sachio Kobayashi, Hiroki Kobayashi, Masayoshi Hashima, Tomotake Sasaki
  • Publication number: 20160006347
    Abstract: A power supply apparatus includes: an inductor to which an input voltage is applied; a switching element that switches a current flowing to the inductor on and off so as to cause an induced voltage to be generated; an electrolytic capacitor that smoothes the induced voltage and outputs the voltage to a load; and a control circuit that controls the switching element, wherein the control circuit outputs a second switching control signal obtained by superimposing a degradation detection-purpose signal for detecting degradation of the electrolytic capacitor on a first control signal, detects an output voltage output by switching performed by the switching element controlled by the second control signal, and estimates the degradation of the electrolytic capacitor by using the output voltage detected, a duty cycle of the first control signal, and a frequency component of the degradation detection-purpose signal contained in the output voltage detected.
    Type: Application
    Filed: June 23, 2015
    Publication date: January 7, 2016
    Applicant: Fujitsu Limited
    Inventors: Yoshinobu MATSUI, Hisato HOSOYAMA, Tomotake SASAKI
  • Publication number: 20150346788
    Abstract: A control device includes a processor that executes a process including generating a driving signal that drives a switching device, so that an output voltage of a converter circuit that performs a step-down conversion on input power by driving the switching device matches a target value, and modifying the target value so that as an output current of the converter circuit becomes lower the output voltage becomes closer to an upper limit value of the output voltage.
    Type: Application
    Filed: May 12, 2015
    Publication date: December 3, 2015
    Inventors: Tomotake Sasaki, Yu Yonezawa, Junji Kaneko, YOSHIYASU NAKASHIMA
  • Publication number: 20150138851
    Abstract: A PFC circuit generates substantially sinusoidal current that is in-phase with AC input voltage to compensate for a power factor. A DC-DC converter converts the voltage of a signal outputted from the PFC circuit to determined voltage. A current change detection section detects an amount of change in current outputted from the DC-DC converter, compares the detected amount of change in current with a threshold set in advance, and if the detected amount of change in current is larger than the threshold, outputs a gain switching signal for raising the gain of voltage outputted from the PFC circuit. The current change detection section outputs a voltage control signal for raising the voltage outputted from the PFC circuit to a determined value. A voltage setting section sets the voltage outputted from the PFC circuit to the determined value on the basis of the voltage control signal.
    Type: Application
    Filed: November 4, 2014
    Publication date: May 21, 2015
    Inventors: Yu Yonezawa, Tomotake Sasaki, Yoshinobu Matsui, YOSHIYASU NAKASHIMA
  • Publication number: 20140344812
    Abstract: A computer system includes servers having virtual machines arranged therein; a noise source in each among the servers, the noise source emitting sound when the server is operated; and a controller that controls arrangement of the virtual machines in the servers. The controller solves an integer programming problem having an objective function representing a noise contribution described as any one among a function of virtual machine arrangement and a function of a job assignment count and indicating an extent of contribution of the sound emitted from the noise source to a noise volume at an evaluation point, by executing software for solving the integer programming problem on a processor, and based on a solution to the integer programming problem, causes the processor to arrange the virtual machines in the servers via an interface for the servers.
    Type: Application
    Filed: August 5, 2014
    Publication date: November 20, 2014
    Inventors: Hideki ABE, Sachio KOBAYASHI, Hiroki KOBAYASHI, Masayoshi HASHIMA, Tomotake SASAKI
  • Publication number: 20140249793
    Abstract: A control server according to an embodiment sorts a plurality of notebook PCs into a plurality of groups so that the total value of the remaining amounts is a value similar to the total value of the remaining amounts of the rechargeable batteries of a plurality of notebook PCs included in a different group. The control server according to the embodiment performs local search individually on the sorted groups, and generates a control plan for the individual notebook PCs.
    Type: Application
    Filed: February 28, 2014
    Publication date: September 4, 2014
    Applicants: The University of Tokyo, FUJITSU LIMITED
    Inventors: Hitoshi Yanami, Hidenao Iwane, Tomotake Sasaki, Hirokazu Anai, Junji Kaneko, Shinji Hara, Suguru Fujita
  • Publication number: 20140232365
    Abstract: A control device includes: a power supply circuit that controls output voltage using a switching element; a generation unit that generates a reference signal on the basis of the output voltage from the power supply circuit; a PWM unit that generates a PWM signal that is output to the switching element by comparing the reference signal with a carrier signal; and a switching unit that switches a frequency of the carrier signal by changing amplitude of the carrier signal, wherein the generation unit generates the reference signal on the basis of the frequency.
    Type: Application
    Filed: December 3, 2013
    Publication date: August 21, 2014
    Applicant: Fujitsu Limited
    Inventors: Tomotake SASAKI, Tsugito MARUYAMA, Yu YONEZAWA, Yoshiyasu NAKASHIMA
  • Publication number: 20140208322
    Abstract: A computer system includes plural servers in which virtual machines are arranged; plural power supply apparatuses that supply electric power to the servers; and a control apparatus that controls arrangement of the virtual machines in the servers. The control apparatus solves an integer programming problem whose objective function is total power consumption by the servers and by the power supply apparatuses, the total power consumption being described as a function of the arrangement of the virtual machines; and arranges the virtual machines based on a solution of the integer programming problem.
    Type: Application
    Filed: March 24, 2014
    Publication date: July 24, 2014
    Applicant: FUJITSU LIMITED
    Inventors: Tomotake Sasaki, Yuichi Sato, Hiroki Kobayashi, Sachio Kobayashi
  • Publication number: 20140088940
    Abstract: A thermofluid simulation method includes referring to a storage unit storing a simulation result corresponding to a predetermined analysis range including partial spaces set in a space subject to simulation, and a first reduced order model generated based on the simulation result, generating a second reduced order model derived from the simulation result thus referred to for an analysis range having an arrangement of partial spaces matching an arrangement of the partial spaces of the predetermined analysis range in the space subject to simulation, and storing the generated second reduced order model in the storage unit, and interpolating reduced order models among reduced order models stored in the storage unit based on a boundary condition to form a reduced order model group corresponding to variable ranges of the boundary condition, the reduced order model group including the first, and the second reduced order models.
    Type: Application
    Filed: September 4, 2013
    Publication date: March 27, 2014
    Applicant: FUJITSU LIMITED
    Inventors: SACHIO KOBAYASHI, Hiroki KOBAYASHI, Tomotake SASAKI, Hiroshi IKEDA, YUHEI UMEDA