Electric power system monitoring device and electric power system monitoring system

Patent metadata

Field	Value
Publication number	US-10222196-B2
Application number	US-201515511341-A
Country	US
Kind code	B2
Filing date	May 28, 2015
Priority date	Sep 24, 2014
Publication date	Mar 5, 2019
Grant date	Mar 5, 2019

Abstract

The present invention monitors an electric power system using a time-series measurement value including abnormality. An electric power system monitoring device is provided with: a storage unit that stores facility information indicating a position relationship of a plurality of measurement sites in an electric power system; a reception unit that receives time-series measurement information measured by a measurement device disposed at each of the plurality of measurement sites; and a computation unit that acquires an electrical distance between the plurality of measurement sites on the basis of the facility information, classifies the plurality of measurement sites into at least one measurement site group on the basis of the electrical distance, extracts, with respect to each of the measurement sites in the measurement site group, a frequency component of electric power fluctuation from the measurement information, selects, with respect to a first frequency component which is a frequency component of a first measurement site in the measurement site group, a second frequency component which is a frequency component of a second measurement site in the measurement site group, and calculates a similarity between the first frequency component and the second frequency component.

First claim

The invention claimed is:

1. An electric power system monitoring device that monitors an electric power system state, comprising:
a measurement device disposed at each of a plurality of measurement sites in an electric power system;
a storage unit that stores facility information indicating a position relationship of the plurality of measurement sites in the electric power system;
a reception unit that receives time-series measurement information measured by the measurement device disposed at each of the plurality of measurement sites;
a computation unit that acquires an electrical distance between the plurality of measurement sites on the basis of the facility information, classifies the plurality of measurement sites into at least one measurement site group on the basis of the electrical distance, extracts a frequency component of electric power fluctuation from the measurement information with respect to each of the measurement sites in the measurement site group, selects a second frequency component which is a frequency component of a second measurement site in the measurement site group with respect to a first frequency component which is a frequency component of a first measurement site in the measurement site group, and calculates a similarity between the first frequency component and the second frequency component; and
a user interface through which a user controls operation of the electric power system monitoring device;
wherein the facility information indicates at least one of a latitude and longitude of each of the plurality of measurement sites, a topology between the plurality of measurement sites, impedance between the plurality of measurement sites, and a feature of an electric power device linked to a vicinity of each of the plurality of measurement sites.

2. The electric power system monitoring device according to claim 1 ,
wherein the computation unit calculates at least one of a fluctuation frequency, an attenuation coefficient, and an amplitude of the frequency component as a feature amount, compares a feature amount of the first frequency component to feature amounts of sites other than the first measurement site in the measurement site group, and selects the second frequency component among the sites other than the first measurement site in the measurement site group on the basis of a comparison result.

3. The electric power system monitoring device according to claim 2 ,
wherein in a case in which the similarity between the first frequency component and the second frequency component satisfies a pre-decided similarity condition, the computation unit calculates measurement information regarding a specific time of the first measurement site on the basis of a feature amount of the second frequency component.

4. The electric power system monitoring device according to claim 3 ,
wherein the computation unit calculates an importance indicating a magnitude of influence of the frequency component on stability of the electric power system with respect to each frequency component of each measurement site in the measurement site group on the basis of the feature amount and calculates the similarity between the first frequency component and the second frequency component on the basis of the importance of the first frequency component and the importance of the second frequency component.

5. The electric power system monitoring device according to claim 4 ,
wherein the computation unit selects a measurement site in which abnormality in the measurement information satisfies a predetermined abnormality condition in the measurement site group as the first measurement site.

6. The electric power system monitoring device according to claim 4 ,
wherein the storage unit stores importances of a plurality of previous fluctuation frequency components, and
wherein the computation unit selects the importance corresponding to a situation of the electric power system among the importances of the plurality of previous fluctuation frequency components and calculates the importance of each frequency component on the basis of the selected importance.

7. The electric power system monitoring device according to claim 1 ,
wherein in the computation unit, the electrical distance between two measurement sites among the plurality of measurement sites is proportional to an impedance between the two measurement sites.

8. The electric power system monitoring device according to claim 1 ,
wherein on the basis of the facility information, the computation unit causes a display device to display a screen indicating the first measurement site and the second measurement site along with one of a system diagram and map of the electric power system.

9. An electric power system monitoring system that monitors an electric power system state, comprising:
a plurality of measurement devices that are respectively disposed at a plurality of measurement sites in the electric power system;
a monitoring device that is connected to the plurality of measurement devices via communication lines,
wherein the monitoring device includes
a storage unit that stores facility information indicating a position relationship of the plurality of measurement sites in the electric power system,
a reception unit that receives time-series measurement information measured by the measurement device disposed at each of the plurality of measurement sites, and
a computation unit that acquires an electrical distance between the plurality of measurement sites on the basis of the facility information, classifies the plurality of measurement sites into at least one measurement site group on the basis of the electrical distance, extracts a frequency component of electric power fluctuation from the measurement information with respect to each of the measurement sites in the measurement site group, selects a second frequency component which is a frequency component of a second measurement site in the measurement site group with respect to a first frequency component which is a frequency component of a first measurement site in the measurement site group, and calculates a similarity between the first frequency component and the second frequency component; and
a user interface through which a user controls operation of the monitoring device;
wherein the facility information indicates at least one of a latitude and longitude of each of the plurality of measurement sites, a topology between the plurality of measurement sites, impedance between the plurality of measurement sites, and a feature of an electric power device linked to a vicinity of each of the plurality of measurement sites.

Assignees

• Hitachi Ltd

Inventors

• Yamazaki Jun
• Yatsu Masahiro
• Tobe Sumito
• Tomobe Osamu
• Inuduka Tatsuki

Classifications

• H02J13/1311

  using the power network as support for the transmission · CPC title

• H02J13/333

  the equipment forming part of substations · CPC title

• H02J13/1337 Primary

  involving the use of Internet protocols · CPC title

• H02J3/381

  Dispersed generators · CPC title

• Y04S10/12

  Monitoring or controlling equipment for energy generation units, e.g. distributed energy generation [DER] or load-side generation · CPC title