Equipment failure detection in an electric power system

Patent metadata

Field	Value
Publication number	US-11112466-B2
Application number	US-202016796563-A
Country	US
Kind code	B2
Filing date	Feb 20, 2020
Priority date	Oct 13, 2019
Publication date	Sep 7, 2021
Grant date	Sep 7, 2021

Abstract

The present disclosure pertains to devices, systems, and methods for monitoring an electric power system. In one embodiment, a system may detect a failure in an electric power system. The system may include a communication interface to receive a first indication related to a condition in the electric power system, and a second indication related to the condition. The system may also include a test subsystem to compare the first indication to the second indication and to determine a discrepancy between the first indication and the second indication. A diagnostic subsystem may identify the failure based on the discrepancy between the first indication and the second indication. An alert subsystem may generate an alert based on the failure.

First claim

What is claimed is:

1. A system to detect a failure in an electric power system, the system comprising:
a communication interface to receive:
a first indication related to a condition in the electric power system; and
a second indication related to the condition;

a test subsystem to:
compare the first indication to the second indication;
determine a discrepancy between the first indication and the second indication;

a diagnostic subsystem to identify the failure based on the discrepancy between the first indication and the second indication; and
an alert subsystem to generate an alert based on the failure;
wherein:
the first indication comprises an input to a protective relay;
the second indication comprises an output from the protective relay; and
the diagnostic subsystem identifies the failure based on a difference between the output from the protected relay and an expected output from the protective relay based on the input.

2. The system of claim 1 , wherein the first indication is generated by a first primary protective relay and the second indication is generated by a second primary protective relay.

3. The system of claim 1 , wherein:
the first indication comprises a first measurement of an electric current generated by a first current-sensing device;
the second indication comprises a second measurement of an electric current generated by a second current-sensing device; and
the diagnostic subsystem identifies the failure based on a difference between the electric current measured by the first current-sensing device and the second current-sensing device.

4. The system of claim 1 , wherein:
the first indication comprises a first measurement of a voltage generated by a first voltage-sensing device;
the second indication comprises a second measurement of a voltage generated by a second voltage-sensing device; and
the diagnostic subsystem identifies the failure based on a difference between the voltage measured by the first voltage-sensing device and the second voltage-sensing device.

5. The system of claim 1 , further comprising a backup subsystem to implement backup protection for the protective relay and to generate the expected output.

6. The system of claim 5 , wherein the protective relay comprises a bus relay.

7. The system of claim 5 , wherein the protective relay comprises a feeder relay.

8. The system of claim 5 , wherein the protective relay comprises a transformer relay.

9. The system of claim 1 , wherein:
the diagnostic subsystem further identifies a component responsible for the failure; and
the alert identifies the component.

10. The system of claim 1 , wherein the discrepancy comprises a loss of a communication link.

11. A system to detect a failure in an electric power system, the system comprising:
a communication interface to receive:
a first indication related to a condition in the electric power system; and
a second indication related to the condition;

a test subsystem to:
compare the first indication to the second indication;
determine a discrepancy between the first indication and the second indication;

a diagnostic subsystem to identify the failure based on the discrepancy between the first indication and the second indication; and
an alert subsystem to generate an alert based on the failure;
wherein:
the first indication comprises a status of an output contact;
the second indication comprises a measurement of a condition associated with the status of the output contact; and
the diagnostic subsystem identifies the failure based on a difference between the status of the output contact and the condition associated with the status of the output contact.

12. A system to detect a failure in an electric power system, the system comprising:
a communication interface to receive:
a first indication related to a condition in the electric power system; and
a second indication related to the condition;

a test subsystem to:
compare the first indication to the second indication;
determine a discrepancy between the first indication and the second indication;

a diagnostic subsystem to identify the failure based on the discrepancy between the first indication and the second indication;
an alert subsystem to generate an alert based on the failure; and
a condition-based monitoring subsystem to:
receive information over time regarding operation of a piece of equipment in the electric power system;
perform a predictive analysis based on the information; and
generate an assessment of a remaining useful life of the piece of equipment.

13. A method for detecting a failure in an electric power system, the method comprising:
receiving a first indication related to a condition in the electric power system;
receiving a second indication related to the condition;
comparing the first indication to the second indication;
determining a discrepancy between the first indication and the second indication;
identifying the failure based on the discrepancy between the first indication and the second indication; and
generating an alert based on the failure;
wherein:
the first indication comprises an input to a protective relay;
the second indication comprises an output from the protective relay; and
identifying the failure based on a difference between the output from the protected relay and an expected output from the protective relay based on the input.

14. The method of claim 13 , wherein the first indication is generated by a first primary protective relay and the second indication is generated by a second primary protective relay.

15. The method of claim 13 , wherein:
the first indication comprises a first measurement generated by a first current-sensing device of an electric current;
the second indication comprises a second measurement generated by a second current-sensing device of the electric current; and
identifying the failure comprises identifying a difference between the electric current measured by the first current-sensing device and the second current-sensing device.

16. The method of claim 13 , wherein:
the first indication comprises a first measurement of an electric current flowing into an electrical node;
the second indication comprises a second measurement of an electric current flowing out of the electrical node; and
identifying the failure comprises identifying that the electric current flowing into the electrical node does not equal the electric current flowing out of the electrical node.

17. The method of claim 13 , wherein:
the first indication comprises a first measurement of a voltage generated by a first voltage-sensing device;
the second indication comprises a second measurement of a voltage generated by a second voltage-sensing device; and
identifying the failure based on a difference between the voltage measured by the first voltage-sensing device and the second voltage-sensing device.

18. The method of claim 13 , further comprising:
implementing backup protection for the protective relay; and
generating the expected output.

19. The method of claim 13 , wherein the protective relay comprises a bus relay.

20. The method of 14 , wherein the protective relay comprises a feeder relay.

21. The method of 14 , wherein the protective relay comprises a transformer relay.

22. The method of claim 13 , wherein:
the first indication comprises a status of an output contact;
the second indication comprises a measurement of a condition associated wit

Assignees

• Schweitzer Engineering Lab Inc

Inventors

• Schweitzer Iii Edmund O
• Lee Tony J
• Whitehead David E
• Casebolt David J
• Gubba Ravikumar Krishnanjan
• Wade Austin Edward
• Nelms Lisa Gayle

Classifications

• H02H3/05

  with means for increasing reliability, e.g. redundancy arrangements {(for logic circuits H03K19/003)} · CPC title

• H02H7/261

  involving signal transmission between at least two stations (transmission of signals in general H02H1/0061) · CPC title

• G01R35/00

  Testing or calibrating of apparatus covered by the other groups of this subclass · CPC title

• H01F27/402

  Association of measuring or protective means · CPC title

• H02H7/04

  for transformers · CPC title