Patents by Inventor Shota OMI

Shota OMI 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: 11811409
    Abstract: In order to suppress frequency fluctuation caused by a load frequency, an AR calculating section calculates an AR using system frequency deviation and tie-line power flow deviation as inputs. An output distribution ratio determining section determines a ratio of output distribution according to merit order based on the AR calculated by the AR calculating section. An output distributing section determines output distribution according to an output change speed based on the output distribution ratio determined by the output distribution ratio determining section according to the output change speed. An output distributing section determines output distribution according to the merit order based on the output distribution ratio determined by the output distribution ratio determining section according to the merit order.
    Type: Grant
    Filed: January 24, 2020
    Date of Patent: November 7, 2023
    Assignee: HITACHI, LTD.
    Inventors: Yuki Tsujii, Shota Omi
  • Publication number: 20220263312
    Abstract: A regulated power procurement segment determination unit refers to a renewable energy theoretical maximum value database and a renewable energy output database and determines segments for procurement of regulated power, a demand/supply control simulation unit refers to the renewable energy output database, a demand database, and a power generator database, performs demand/supply control simulation by using the segments for procurement of regulated power, renewable energy output data, demand data, and power generator data, and predicts, on the basis of the demand/supply control simulation results, frequency changes and procurement costs regarding the segments for procurement of regulation power, and a segment selection unit refers to a cost database and a frequency change database and selects a segment for procurement of regulation power on the basis of the frequency changes and the procurement costs regarding the segments on which prediction has been performed.
    Type: Application
    Filed: April 14, 2020
    Publication date: August 18, 2022
    Inventors: Yuki TSUJII, Shota OMI
  • Publication number: 20220123739
    Abstract: In order to suppress frequency fluctuation caused by a load frequency, an AR calculating section calculates an AR using system frequency deviation and tie-line power flow deviation as inputs. An output distribution ratio determining section determines a ratio of output distribution according to merit order based on the AR calculated by the AR calculating section. An output distributing section determines output distribution according to an output change speed based on the output distribution ratio determined by the output distribution ratio determining section according to the output change speed. An output distributing section determines output distribution according to the merit order based on the output distribution ratio determined by the output distribution ratio determining section according to the merit order.
    Type: Application
    Filed: January 24, 2020
    Publication date: April 21, 2022
    Applicant: Hitachi, Ltd.
    Inventors: Yuki TSUJII, Shota OMI
  • Patent number: 11035892
    Abstract: There is provided an electric power system monitoring apparatus that can estimate dynamic behavior constants using measurement signals and can obtain the accuracy of an estimation result. An apparatus according to the present invention that monitors an electric power system includes a dynamic behavior constant estimation unit to estimate a predetermined dynamic behavior constant from a measurement value obtained from the electric power system, a relative accuracy calculation unit to calculate, from the measurement value, a relative accuracy index that indicates accuracy of a dynamic behavior constant estimation value estimated at the dynamic behavior constant estimation unit, and an estimation error calculation unit to calculate an estimation error from reference dynamic behavior information, the dynamic behavior constant estimation value, and the relative accuracy index. Thus, after the accuracy of a dynamic behavior constant estimation value is grasped, a process using the estimation value can be executed.
    Type: Grant
    Filed: November 9, 2016
    Date of Patent: June 15, 2021
    Assignee: Hitachi, Ltd.
    Inventors: Masatoshi Kumagai, Shota Omi, Kenichirou Yamane
  • Patent number: 10860000
    Abstract: It is possible by means of a system simulation device to extract a disturbance mode wherein multiple accident conditions are assumed and to determine control parameters, but when the number of accident conditions increases, a threshold value pertaining to a divergence constant deviates prior to an update period, with the result that an uncontrollable disturbance mode appears.
    Type: Grant
    Filed: April 24, 2015
    Date of Patent: December 8, 2020
    Assignee: Hitachi, Ltd.
    Inventors: Shota Omi, Masatoshi Kumagai, Kenichiro Yamane
  • Patent number: 10581245
    Abstract: The setting range of the voltage and the reactive power of a power system is maintained during variations of voltage and power flow due to the output variation of renewable energy of a large number of power supplies which fluctuate due to weather. A voltage/reactive power operation assisting device is provided with a first database for storing the data to be evaluated, target value data, individual control device control method data, and individual control device data of an individual control device for adjusting the voltage/reactive power of a power system. A second database stores the device operation data of the individual control device; and the operation of the individual control device is predicted from the data stored in the first database to obtain individual control device operation prediction data. A display unit displays the individual control device operation prediction data and the device operation data in a contrastive manner.
    Type: Grant
    Filed: September 4, 2017
    Date of Patent: March 3, 2020
    Assignee: Hitachi, Ltd.
    Inventors: Eisuke Kuroda, Nao Saito, Kouichi Hara, Masahiro Yatsu, Taichiro Kawahara, Shota Omi
  • Publication number: 20190280481
    Abstract: The setting range of the voltage and the reactive power of a power system is maintained during variations of voltage and power flow due to the output variation of renewable energy of a large number of power supplies which fluctuate due to weather. A voltage/reactive power operation assisting device is provided with a first database for storing the data to be evaluated, target value data, individual control device control method data, and individual control device data of an individual control device for adjusting the voltage/reactive power of a power system. A second database stores the device operation data of the individual control device; and the operation of the individual control device is predicted from the data stored in the first database to obtain individual control device operation prediction data. A display unit displays the individual control device operation prediction data and the device operation data in a contrastive manner.
    Type: Application
    Filed: September 4, 2017
    Publication date: September 12, 2019
    Inventors: Eisuke KURODA, Nao SAITO, Kouichi HARA, Masahiro YATSU, Taichiro KAWAHARA, Shota OMI
  • Patent number: 10389127
    Abstract: A system stabilization system (101) is provided with: at least one of a power flow state database (DB2) and a system configuration database (DB3); a device state database (DB1) in which the device states of a stabilizing device are recorded; a stabilizing effect index calculation function (204) for indexing the stabilizing effect of the stabilizing device on the basis of a device state and one or both of a power flow state and a system configuration; and a display means for displaying or outputting a stabilizing effect index obtained by the stabilizing effect index calculation function, in contrast with contrasted elements included in the device state, the power flow state, and the system configuration.
    Type: Grant
    Filed: March 9, 2015
    Date of Patent: August 20, 2019
    Assignee: Hitachi, Ltd.
    Inventors: Masatoshi Kumagai, Yukihiro Takatani, Shota Omi, Kenichiro Yamane
  • Patent number: 10361560
    Abstract: A power system control instruction device performing a control instruction to the control device that controls the power system on the basis of a measured value transmitted from a sensor measuring a state value of the power system and a method for performing such a control instruction are provided. The device obtains a centralized control amount using a measured value of the sensor such that a system voltage meets a predetermined control purpose, and creates a distributed control model using the measured value and the centralized control amount. The device then determines whether or not a voltage deviation from the voltage appropriate range occurs when the control device performs control on the basis of the distributed control model, and re-creates the distributed control model when the voltage deviation occurs, and transmits the distributed control model that is re-created to the control device.
    Type: Grant
    Filed: March 31, 2014
    Date of Patent: July 23, 2019
    Assignee: Hitachi, Ltd.
    Inventors: Shota Omi, Masatoshi Kumagai, Kenichiro Yamane, Masahiro Watanabe
  • Publication number: 20180313876
    Abstract: There is provided an electric power system monitoring apparatus that can estimate dynamic behavior constants using measurement signals and can obtain the accuracy of an estimation result. An apparatus according to the present invention that monitors an electric power system includes a dynamic behavior constant estimation unit to estimate a predetermined dynamic behavior constant from a measurement value obtained from the electric power system, a relative accuracy calculation unit to calculate, from the measurement value, a relative accuracy index that indicates accuracy of a dynamic behavior constant estimation value estimated at the dynamic behavior constant estimation unit, and an estimation error calculation unit to calculate an estimation error from reference dynamic behavior information, the dynamic behavior constant estimation value, and the relative accuracy index. Thus, after the accuracy of a dynamic behavior constant estimation value is grasped, a process using the estimation value can be executed.
    Type: Application
    Filed: November 9, 2016
    Publication date: November 1, 2018
    Inventors: Masatoshi KUMAGAI, Shota OMI, Kenichirou YAMANE
  • Publication number: 20180120818
    Abstract: It is possible by means of a system simulation device to extract a disturbance mode wherein multiple accident conditions are assumed and to determine control parameters, but when the number of accident conditions increases, a threshold value pertaining to a divergence constant deviates prior to an update period, with the result that an uncontrollable disturbance mode appears.
    Type: Application
    Filed: April 24, 2015
    Publication date: May 3, 2018
    Inventors: Shota OMI, Masatoshi KUMAGAI, Kenichiro YAMANE
  • Publication number: 20180054058
    Abstract: A system stabilization system (101) is provided with: at least one of a power flow state database (DB2) and a system configuration database (DB3); a device state database (DB1) in which the device states of a stabilizing device are recorded; a stabilizing effect index calculation function (204) for indexing the stabilizing effect of the stabilizing device on the basis of a device state and one or both of a power flow state and a system configuration; and a display means for displaying or outputting a stabilizing effect index obtained by the stabilizing effect index calculation function, in contrast with contrasted elements included in the device state, the power flow state, and the system configuration.
    Type: Application
    Filed: March 9, 2015
    Publication date: February 22, 2018
    Inventors: Masatoshi KUMAGAI, Yukihiro TAKATANI, Shota OMI, Kenichiro YAMANE
  • Patent number: 9780563
    Abstract: A distributed controller collects measurement value data of a voltage and a current in an own node and in another node; using the measurement voltage and the current of the own node and the measurement voltage and current of another node as input data, estimates a voltage or a current as a state quantity of the electric power system regarding another node from which the measurement value data cannot be collected, and outputs the estimate values; using the measurement data, the estimate value outputted from the state estimation functional unit and a voltage target value that has been set for each node, outputs the control commands for voltage controllers based on voltage change amounts to be distributed to the voltage control devices of the nodes including the own node. The voltages in the electric power system are controlled by superposition of voltage change amounts by the voltage control devices.
    Type: Grant
    Filed: February 28, 2013
    Date of Patent: October 3, 2017
    Assignee: Hitachi, Ltd.
    Inventors: Masatoshi Kumagai, Shota Omi, Kenichiro Yamane, Yasushi Harada, Masahiro Watanabe, Yasuo Sato, Yasushi Tomita
  • Publication number: 20170141572
    Abstract: An object is to create a control model which can maintain a voltage of a power system within an appropriate range regardless of quality of communication between a control instruction device that calculates a control amount and a control device that executes a predetermined operation on the basis of the control amount.
    Type: Application
    Filed: March 31, 2014
    Publication date: May 18, 2017
    Inventors: Shota OMI, Masatoshi KUMAGAI, Kenichiro YAMANE, Masahiro WATANABE
  • Publication number: 20160238669
    Abstract: A power system state estimation device for estimating a state amount of a power system having: a calculation unit which executes calculations on the power system; a system division unit which is inputted with system information and a measured value of the state amount of the power system to divide the power system into an observable subsystem and an unobservable subsystem; a state estimation unit that is inputted with the system information and the measured value of the state amount to calculate an estimated value of the state amount in the observable subsystem divided by the system division unit; and a state range estimation unit that is inputted with the system information, the measured value of the state amount and a constraint value of the state amount of the power system to calculate an estimated range of the state amount in the unobservable subsystem divided by the system division unit.
    Type: Application
    Filed: October 7, 2013
    Publication date: August 18, 2016
    Inventors: Masatoshi KUMAGAI, Shota OMI, Kenichiro YAMANE, Masahiro WATANABE
  • Publication number: 20160013648
    Abstract: A distributed controller collects measurement value data of a voltage and a current in an own node and in another node; using the measurement voltage and the current of the own node and the measurement voltage and current of another node as input data, estimates a voltage or a current as a state quantity of the electric power system regarding another node from which the measurement value data cannot be collected, and outputs the estimate values; using the measurement data, the estimate value outputted from the state estimation functional unit and a voltage target value that has been set for each node, outputs the control commands for voltage controllers based on voltage change amounts to be distributed to the voltage control devices of the nodes including the own node. The voltages in the electric power system are controlled by superposition of voltage change amounts by the voltage control devices.
    Type: Application
    Filed: February 28, 2013
    Publication date: January 14, 2016
    Inventors: Masatoshi KUMAGAI, Shota OMI, Kenichiro YAMANE, Yasushi HARADA, Masahiro WATANABE, Yasuo SATO, Yasushi TOMITA