公开(公告)号：US12132336B2

公开(公告)日：2024-10-29

申请号：US17762189

申请日：2020-07-22

Applicant: Hitachi, Ltd.

Inventor： Tsutomu Kawamura ,  Ryousuke Nakamura ,  Tetsushi Ono ,  Masatoshi Kumagai

IPC: G05B19/042 ,  B60L53/66 ,  B60L58/12 ,  H02J7/00

CPC classification number: H02J7/0032 ,  B60L53/66 ,  B60L58/12 ,  G05B19/042 ,  H02J7/0048 ,  H02J7/0063 ,  H02J7/0068 ,  G05B2219/2639

Abstract: This regional energy management device calculates the power interchange between consumers, on the basis of: storage battery level distribution indicating the relationship between storage battery levels and the position of storage batteries in a region at each time; excess or shortages of power for each consumer at each time, if a consumer has implemented a power supply equipment operation plan for fulfilling a consumer target index for that consumer; and an overall regional target index.

公开(公告)号：US11456619B2

公开(公告)日：2022-09-27

申请号：US16980491

申请日：2019-03-11

Applicant: Hitachi, Ltd.

Inventor： Tsutomu Kawamura ,  Masatoshi Kumagai ,  Hirotaka Takahashi ,  Ryousuke Nakamura

IPC: H02J13/00 ,  G05F1/66 ,  G06Q50/06

Abstract: Included are an energy management apparatus that manages at least one or more management target that consumes energy; and a user terminal that transmits and receives information to and from the energy management apparatus via a network. The energy management apparatus includes an energy management controller that prepares a question regarding a behavior of a user who uses the at least one or more management target, and transmits it to the user terminal. The user terminal includes a user terminal controller that transmits a question answer regarding the received question to the energy management controller when receiving the question transmitted from the energy management controller. The energy management controller predicts an energy consumption amount of the at least one or more management target based on the received question answer when receiving the question answer transmitted from the user terminal controller.

公开(公告)号：US10389127B2

公开(公告)日：2019-08-20

申请号：US15554273

申请日：2015-03-09

Applicant: Hitachi, Ltd.

Inventor： Masatoshi Kumagai ,  Yukihiro Takatani ,  Shota Omi ,  Kenichiro Yamane

IPC: H02J3/18 ,  H02J3/24 ,  G06Q50/06 ,  H02J13/00

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.

公开(公告)号：US11121553B2

公开(公告)日：2021-09-14

申请号：US16652091

申请日：2017-10-31

Applicant: Hitachi, Ltd.

Inventor： Yuki Tsujii ,  Masatoshi Kumagai ,  Kenedward Kawakita ,  Masahiro Watanabe

IPC: H02J3/24 ,  H02J13/00 ,  G05B15/02

Abstract: There is provided a power system stability analysis device that analyzes stability of a power system by obtaining measurement data from a high-accuracy measurement device and existing measuring instruments installed in the power system, the apparatus including: a system state estimation unit that estimates a system state of the power system by using measurement data from the existing measuring instruments at a plurality of points in the power system; a synchronous stability analysis unit that analyzes synchronous stability in an assumed failure by using an estimation result of the system state; and a synchronous stability analysis correction unit that corrects the synchronous stability according to a difference between the estimation result of the system state and the measurement data of the high-accuracy measurement device to improve accuracy of synchronous stability analysis of the power system.

公开(公告)号：US10361560B2

公开(公告)日：2019-07-23

申请号：US15129721

申请日：2014-03-31

Applicant: Hitachi, Ltd.

Inventor： Shota Omi ,  Masatoshi Kumagai ,  Kenichiro Yamane ,  Masahiro Watanabe

IPC: H02J3/12 ,  H02J13/00 ,  G05B17/02

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.

公开(公告)号：US10860000B2

公开(公告)日：2020-12-08

申请号：US15566461

申请日：2015-04-24

Applicant: Hitachi, Ltd.

Inventor： Shota Omi ,  Masatoshi Kumagai ,  Kenichiro Yamane

IPC: G05B19/4093 ,  H02J3/24 ,  G05B19/418 ,  G05F1/66 ,  H02J3/18 ,  H02P9/10 ,  H02J3/38

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. In order to solve this problem, the present invention is a power system stabilization system for determining control parameters for a control device connected to a power system, the power system stabilization system equipped with: a disturbance mode prediction unit for predicting a disturbance mode of a power system on the basis of operation information and an assumed system configuration for the power system; a post-control parameter update period prediction unit for predicting an update period for a post-control parameter in post-control after a disturbance has occurred; a threshold value setting unit for setting a threshold value pertaining to a divergence constant on the basis of the disturbance mode and the update period for the post-control parameter; and a control parameter determination unit for determining a control parameter of the control device on the basis of the disturbance mode and the threshold value.

公开(公告)号：US11088569B2

公开(公告)日：2021-08-10

申请号：US16339078

申请日：2017-09-13

Applicant: Hitachi, Ltd.

Inventor： Yuki Tsujii ,  Kenedward Kawakita ,  Masatoshi Kumagai ,  Masahiro Watanabe ,  Akira Kikuchi

IPC: H02J13/00 ,  G05B19/042 ,  H02J3/00 ,  H02J3/24 ,  G05B23/02

Abstract: The purpose of the present invention is to provide a power flow monitoring device for a power system, a power system stabilization device, and a power flow monitoring method for a power system, which are highly reliable and accurate. The present invention is characterized by being provided with: a power system information database which stores measurement data obtained at a first node of the power system; a phase measurement value database which stores temporally synchronized phase measurement data obtained at a second node of the power system; a fault condition database which stores a power flow state under an assumed fault condition of the power system; a state estimation unit which estimates a state quantity of the power system using information in the power system information database as an input; a stability error detection index calculation unit which calculates a stability error detection index using, as an input, a state quantity estimation value which is an output of the state estimation unit, information of the state quantity from the phase measurement value database, and information in the fault condition database; and an error detection alert generation unit which compares the stability error detection index with a threshold value thereof and generates an alert when the stability error detection index exceeds the threshold value, wherein the magnitude of deviation of the state quantity estimation value with respect to the information of the state quantity from the phase measurement data is evaluated according to the assumed fault condition before the alert is generated.

公开(公告)号：US11035892B2

公开(公告)日：2021-06-15

申请号：US15773022

申请日：2016-11-09

Applicant: Hitachi, Ltd.

Inventor： Masatoshi Kumagai ,  Shota Omi ,  Kenichirou Yamane

IPC: G01R21/133 ,  H02J3/00 ,  H02J13/00 ,  G01R31/34

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.

公开(公告)号：US11042134B2

公开(公告)日：2021-06-22

申请号：US16338039

申请日：2017-10-20

Applicant: Hitachi, Ltd.

Inventor： Masahiro Watanabe ,  Yuki Tsujii ,  KenEdward Kawakita ,  Masatoshi Kumagai

IPC: G05B13/04 ,  G06F17/13 ,  H02J13/00 ,  H02J3/00 ,  G06Q10/04 ,  G06Q50/06 ,  H02J3/18

Abstract: Provided is a power system status estimation device capable of increasing the likelihood that status estimation calculations converge. Thus, a power system status estimation device 1 is equipped with: a measured value selection unit 102 for selecting a prescribed combination of measured values using which it is predicted that the power system status estimation calculations will converge, from among the measured values from each sensor provided in the power system; and a status estimation calculation unit 101 for estimating the status of the power system on the basis of the prescribed combination of measured values selected by the measured value selection unit and the system model for the power system.

公开(公告)号：US10211777B2

公开(公告)日：2019-02-19

申请号：US15113245

申请日：2015-01-14

Applicant: Hitachi, ltd. ,  Tohoku Electric Power Co., Inc. ,  Tohoku Electric Manufacturing Co., Ltd

Inventor： Masahiro Watanabe ,  Kenichiro Yamane ,  Takuya Matsumoto ,  Masatoshi Kumagai ,  Tsukasa Oonishi ,  Ryo Egashira ,  Katsuhiro Matsuda ,  Jun Murakoshi ,  Tomoya Sato

IPC: G01C21/00 ,  H02S50/00 ,  H02J3/38

Abstract: The output of a photovoltaic power generator is estimated by estimating a solar radiation amount at a point different from solar radiation measurement points and determining an estimation error amount from solar radiation values measured at limited points. A photovoltaic power generator output estimation method estimates an output of a photovoltaic power generator based on a measured solar radiation value. The method includes a first estimation method of estimating a solar radiation amount at a photovoltaic power generator installation point from solar radiation meter installation point information, a value measured by a solar radiation meter, and photovoltaic power generator installation point information; a second estimation method of estimating the solar radiation amount at the photovoltaic power generator installation point in a manner different from that of the first estimation method; an output estimation method of estimating the output of the photovoltaic power generator from an estimated solar radiation amount and a rated capacity of the photovoltaic power generator; and an error estimation method of determining an estimation error of a photovoltaic power generator output from a difference between the first and second estimation methods.