Estimating the locations of power system events using PMU measurements

Patent metadata

Field	Value
Publication number	US-9746511-B2
Application number	US-201514952533-A
Country	US
Kind code	B2
Filing date	Nov 25, 2015
Priority date	Nov 25, 2015
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

Example implementations described herein are directed to detection of anomalous events and locations on the transmission power system using phasor management unit (PMU) data, which provides information to grid operators for online decision support. From the high-resolution time synchronized PMU data, the transient abnormal events can be monitored and locations can be disclosed to operators for remedy actions. Utilization of PMU information for such decision support compliments operation practices relying on supervisory control and data acquisition (SCADA) measurements at much lower data resolution. Accurate identification of event locations can further advise grid operators the root cause of disturbances and illuminate possible cascading failures. Implementations of the proposed technology may improve the resilience and reliability of the transmission power systems.

First claim

What is claimed is:

1. A method for event detection for a system comprising a plurality of phasor measurement units (PMUs), the method comprising:
estimating a propagation speed for each PMU in a set of PMUs indicating an anomaly from the plurality of PMUs, the propagation speed based on one or more events stored in a database;
determining a first event location based on the estimated propagation speed for the each of the PMUs in the set of PMUs;
adjusting the estimated propagation speed for each of the PMUs in the set of PMUs based on a distance between the first event location and one or more event locations stored in the database; and
determining a second event location from the adjusting of the estimated propagation speed for each of the PMUs in the set of PMUs.

2. The method of claim 1 , further comprising:
for the second event location being within a threshold distance of the first event location, providing an indication of the second event location as a source of an anomaly;
for the second event location not being within the threshold distance of the first event location:
adjusting the estimated propagation speed for each of the PMUs in the set of PMUs based on a distance between the second event location and one or more event locations stored in the database;
changing the first event location to the second event location; and
re-determining the second event location from the adjusting of the estimated propagation speed for each of the PMUs in the set of PMUs.

3. The method of claim 2 , wherein, for the second event location not being within the threshold distance of the first event location, the adjusting the estimated propagation speed for each of the PMUs in the set of PMUs based on a distance between the first event location and one or more event locations stored in the database, the changing the first event location to the second event location, and the re-determining the second event location from the adjusting of the estimated propagation speed for each of the PMUs in the set of PMUs, are iterated until the second event location is within the threshold distance of the first event location.

4. The method of claim 2 , wherein the adjusting the estimated propagation speed for each of the PMUs in the set of PMUs based on a distance between the first event location and one or more event locations stored in the database comprises including the first event location into the one or more event locations stored in the database, and
wherein the adjusting the estimated propagation speed for each of the PMUs in the set of PMUs based on a distance between the second event location and one or more event locations stored in the database comprises including the first event location and the second event location into the one or more event locations stored in the database.

5. The method of claim 1 , further comprising determining the set of PMUs indicating an anomaly from the plurality of PMUs based on a window of data from each of the plurality of PMUs, wherein the set of PMUs comprises more than one PMU.

6. The method of claim 1 , wherein the estimating the propagation speed for each PMU in a set of PMUs indicating an anomaly from the plurality of PMUs, the propagation speed based on one or more events stored in a database, comprises:
determining the one or more event locations in the database from the one or more events in the database being associated with a PMU in the set of PMUs; and
calculating an average propagation speed for the PMU in the set of PMUs based on a distance from each of the one or more event locations.

7. The method of claim 6 , wherein the adjusting the estimated propagation speed for each of the PMUs in the set of PMUs based on the distance between the second event location and one or more event locations stored in the database comprises:
computing weights inversely proportional to distance between the second event location and each of the one or more event locations; and
adjusting the average propagation speed for the PMU in the set of PMUs based on an application of the weights for each of the one or more event locations.

8. A non-transitory computer readable medium, storing instructions for executing event detection for a system comprising a plurality of phasor measurement units (PMUs), the instructions comprising:
estimating a propagation speed for each PMU in a set of PMUs indicating an anomaly from the plurality of PMUs, the propagation speed based on one or more events stored in a database;
determining a first event location based on the estimated propagation speed for the each of the PMUs in the set of PMUs;
adjusting the estimated propagation speed for each of the PMUs in the set of PMUs based on a distance between the first event location and one or more event locations stored in the database; and
determining a second event location from the adjusting of the estimated propagation speed for each of the PMUs in the set of PMUs.

9. The non-transitory computer readable medium of claim 8 , the instructions further comprising:
for the second event location being within a threshold distance of the first event location, providing an indication of the second event location as a source of an anomaly;
for the second event location not being within the threshold distance of the first event location:
adjusting the estimated propagation speed for each of the PMUs in the set of PMUs based on a distance between the second event location and one or more event locations stored in the database;
changing the first event location to the second event location; and
re-determining the second event location from the adjusting of the estimated propagation speed for each of the PMUs in the set of PMUs.

10. The non-transitory computer readable medium of claim 9 , wherein, for the second event location not being within the threshold distance of the first event location, the adjusting the estimated propagation speed for each of the PMUs in the set of PMUs based on a distance between the first event location and one or more event locations stored in the database, the changing the first event location to the second event location, and the re-determining the second event location from the adjusting of the estimated propagation speed for each of the PMUs in the set of PMUs, are iterated until the second event location is within the threshold distance of the first event location.

11. The non-transitory computer readable medium of claim 9 , wherein the adjusting the estimated propagation speed for each of the PMUs in the set of PMUs based on a distance between the first event location and one or more event locations stored in the database comprises including the first event location into the one or more event locations stored in the database, and
wherein the adjusting the estimated propagation speed for each of the PMUs in the set of PMUs based on a distance between the second event location and one or more event locations stored in the database comprises including the first event location and the second event location into the one or more event locations stored in the database.

12. The non-transitory computer readable medium of claim 8 , the instructions further comprising determining the set of PMUs indicating an anomaly from the plurality of PMUs based on a window of data from each of the plurality of PMUs, wherein the set of PMUs comprises more than one PMU.

13. The non-transitory computer readable medium of claim 8 , wherein the estimating the propagation speed for each PMU in a set of PMUs indicating an anomaly from the plurality of PMUs, the propagation speed based on one or more events stored in a database, comprises:
determinin

Assignees

• Hitachi Ltd

Inventors

• Wang Alex
• Tang Hsiu-Khuern
• Yang Bo
• Yamazaki Jun

Classifications

• G01R31/086 Primary

  in power transmission or distribution networks, i.e. with interconnected conductors · CPC title

• G01R23/02

  Arrangements for measuring frequency, e.g. pulse repetition rate; Arrangements for measuring period of current or voltage · CPC title

• G01P7/00

  Measuring speed by integrating acceleration (measuring travelled distance by double integration of acceleration G01C21/16) · CPC title

• G01P3/50

  for measuring linear speed (G01P3/56 takes precedence) · CPC title

• G01P3/00

  Measuring linear or angular speed; Measuring differences of linear or angular speeds (G01P5/00 - G01P11/00 take precedence; {direction and speed indication G01P13/045}; counting mechanisms G06M) · CPC title