Electric power system monitoring using high-frequency signals

• US 10,180,451 B2
• Filed: 10/13/2016
• Issued: 01/15/2019
• Est. Priority Date: 10/13/2015
• Status: Active Grant

• Current Assignee: Schweitzer Engineering Laboratories, Incorporated
• Original Assignee: Schweitzer Engineering Laboratories, Incorporated
• Inventors: Schweitzer, III, Edmund O., Skendzic, Veselin, Tews, Cody W., Whitehead, David E.
• Primary Examiner(s): Phan, Huy Q
• Assistant Examiner(s): Ferdous, Zannatul
• Application Number:
  US15/292,890
• Publication Number:
  US 20170102426A1
• Time in Patent Office: 824 Days
• CPC Class Codes: G01R 19/0084 measuring voltage only all subgroups of G01R19/00 take precedence
• CPC Class Codes: G01R 31/086 in power transmission or distribution networks, i.e. with interconnected conductors
• CPC Class Codes: G01R 31/088 Aspects of digital computing
• CPC Class Codes: G01R 31/11 using pulse reflection methods

Abstract

A system for monitoring an electric power delivery system by obtaining high-frequency electric power system measurements and displaying event information is disclosed herein. The system may use the high-frequency electric power system information to detect traveling waves. The system may generate a display showing fault location on the electric power system, and timing of traveling waves received at locations on the electric power system. The display may include time on one axis and location on another axis. The display may include a waterfall display.

Claims

1. A system configured to detect a location of a high-frequency signal source in an electric power delivery system by gathering high-frequency electric power system measurements therefrom, the system comprising:

a data acquisition module configured to receive;

a first plurality of high-frequency electric power system measurements from a local terminal;

a second plurality of high-frequency electric power system measurements from a remote terminal, the remote terminal being separated from the local terminal by an electrical power transmission line in the electric power delivery system;

a correlation module configured to time-align the first plurality and the second plurality of high-frequency electric power system measurements based on a common time reference;

an analysis subsystem configured to identify a location of a high-frequency signal source based on the time-aligned first plurality and the second plurality of high-frequency electric power system measurements; and

a visualization subsystem configured to generate a representation of the time-aligned first plurality and the second plurality of high-frequency electric power system measurements and the location of the high-frequency signal source, the location disposed between the local terminal and the remote terminal.

2. The system of claim 1, wherein the representation comprises a waterfall display.

3. The system of claim 2, wherein the waterfall display represents a distance along a first axis and a time along a second axis.

4. The system of claim 3, wherein the waterfall display represents a magnitude along a third axis.

5. The system of claim 3, wherein the waterfall display represents a magnitude using a color scheme.

6. The system of claim 1, wherein the high-frequency signal source comprises a partial discharge activity across a plurality of insulators.

7. The system of claim 6, wherein the analysis subsystem further comprises a line analytics module configured to determine an intensity of the partial discharge at a plurality of locations along a length of the electric transmission line, and the representation reflects the intensity of the partial discharge at the plurality of locations along the length of the electric transmission line.

8. The system of claim 6, wherein the analysis subsystem further comprises a database of statistical information configured to differentiate a signal component attributable to partial discharge activity and a signal component attributable to a corona discharge.

9. The system of claim 1, wherein the high-frequency signal source comprises a corona discharge.

10. The system of claim 1, further comprising a protective action module configured to implement a protective action based on a determination that the high-frequency signal source comprises a fault.

11. The system of claim 1, wherein the analysis subsystem comprises a plurality of correlators, each of the plurality of correlators being associated with a segment of an electrical transmission line in the electric power delivery system.

12. The system of claim 11, wherein each of the plurality of correlators is configured to receive a first measurement from the first plurality of high-frequency electric power system measurements and a second measurement from the second plurality of high-frequency electric power system measurements.

13. The system of claim 11, wherein the plurality of correlators are each associated with an accumulator actuated by a time trigger.

14. The system of claim 1, wherein the visualization subsystem is further configured to generate a report relating to maintenance based on the location of the high-frequency signal source.

15. The system of claim 1, further comprising a time input configured to receive a time signal;

wherein the correlation module is configured to time-align the first plurality and the second plurality of high-frequency electronic power system measurements using the time signal.

16. A method of detecting a location of a high-frequency signal source in an electric power delivery system, comprising:

receiving a first plurality of high-frequency electric power system measurements from a local terminal;

receiving a second plurality of high-frequency electric power system measurements from a remote terminal, the remote terminal being separated from the local terminal by an electrical power transmission line in the electric power delivery system;

time-aligning the first plurality and the second plurality of high-frequency electric power system measurements based on a common time reference;

identifying a location of a high-frequency signal source based on the time-aligned first plurality and the second plurality of high-frequency electric power system measurements; and

generating a representation of the time-aligned first plurality and the second plurality of high-frequency electric power system measurements and the location of the high-frequency signal source at a location disposed between the local terminal and the remote terminal.

17. The method of claim 16, further comprising:

generating a database of statistical information representing a signal component attributable a corona discharge;

using the database to differentiate a signal component attributable to a partial discharge activity and from the signal component attributable to the corona discharge.

18. The method of claim 16, further comprising:

determining that the high-frequency signal source comprises a fault, and

implementing a protective action based on the occurrence of the fault.

19. The method of claim 16, further comprising:

determining an intensity of the partial discharge across a plurality of insulators at a plurality of locations along a length of an electric transmission line in the electric power delivery system, and

wherein generating the representation comprises reflecting the intensity of the partial discharge at the plurality of locations along the length of the electric transmission line.

20. A system configured to detect a location of one of a partial discharge activity across a plurality of insulators and a corona discharge in an electric power delivery system by gathering high-frequency electric power system measurements therefrom, the system comprising:

a data acquisition module configured to receive;

a first plurality of high-frequency electric power system measurements from a local terminal;

a second plurality of high-frequency electric power system measurements from a remote terminal, the remote terminal being separated from the local terminal by an electrical power transmission line in the electric power delivery system;

a correlation module configured to time-align the first plurality and the second plurality of high-frequency electric power system measurements based on a common time reference;

an analysis subsystem configured to identify a location of one of the partial discharge activity across the plurality of insulators and the corona discharge based on the time-aligned first plurality and the second plurality of high-frequency electric power system measurements; and

a visualization subsystem configured to generate a representation of the time-aligned first plurality and the second plurality of high-frequency electric power system measurements and the location of the high-frequency signal source, the location disposed between the local terminal and the remote terminal.