Dynamic real-time power system monitoring

• US 7,848,897 B2
• Filed: 01/30/2008
• Issued: 12/07/2010
• Est. Priority Date: 01/30/2008
• Status: Active Grant

• Current Assignee: Southern Company Services, Inc. (Southern Company)
• Original Assignee: Southern Company Services, Inc. (Southern Company)
• Inventors: Williams, Olin A. Jr.
• Primary Examiner(s): Raymond; Edward
• Application Number:
  US12/022,765
• Publication Number:
  US 20100087959A1
• Time in Patent Office: 1,042 Days
• Field of Search: 702/60, 702/64, 702182-185, 702/188
• US Class Current: 702/60
• CPC Class Codes: H02J 13/00002 characterised by monitoring
• CPC Class Codes: H02J 13/00028 involving the use of Internet protocols
• CPC Class Codes: H02J 13/00034 the elements or equipment being or involving an electric power substation
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y04S 10/30 State monitoring, e.g. fault, temperature monitoring, insulator monitoring, corona discharge

Abstract

A method and system for real-time monitoring of a power system having a plurality of locations forming a transmission and distribution grid, wherein each location includes a plurality of connected components. A plurality of pseudorandom signals are injected at selected locations in the power system. A plurality of power system data are collected at other locations in the power system in response to the injected signals. A dynamic behavior of the power system is determined through a synchronized cross-correlation of the injected signals with the collected power system data. The dynamic behavior of the power system is analyzed to assess a dynamic stability and security state of the power system. The real-time, dynamic stability and security state of the power system is displayed to an operator at a monitoring station. The operational stability and security state can be depicted on an overlay of the nationwide power system grid.

Claims

1. A method for real-time monitoring of a power system having a plurality of locations forming a transmission and distribution grid, wherein each location includes a plurality of connected components, the method comprising:

injecting a plurality of pseudorandom signals at selected locations in the power system;

collecting a plurality of power system data at other locations in the power system in response to the injected signals;

determining a dynamic behavior of the power system through a synchronized cross-correlation of the injected signals with the collected power system data;

analyzing the dynamic behavior of the power system to assess a stability and security state of the power system; and

displaying the stability and security state of the power system to an operator at a monitoring station.

2. The method for real-time monitoring of a power system of claim 1 wherein the pseudorandom signals comprise pseudorandom binary noise sequences.

3. The method for real-time monitoring of a power system of claim 2 wherein the pseudorandom binary noise sequences are injected using a discrete interval binary signal injector.

4. The method for real-time monitoring of a power system of claim 1 further comprising synchronizing the injection of pseudorandom signals with a reference time source.

5. The method for real-time monitoring of a power system of claim 1 wherein the step of injecting pseudorandom signals is performed continuously by a plurality of Internet-connected microcontroller devices deployed at the selected locations in the power system.

6. The method for real-time monitoring of a power system of claim 5 wherein the pseudorandom signals are injected at a generating unit bus.

7. The method for real-time monitoring of a power system of claim 5 wherein the pseudorandom signals are injected at a transmission tie point between neighboring electric utility systems.

8. The method for real-time monitoring of a power system of claim 1 wherein the synchronized cross-correlation of the injected signals with the collected power system data is performed continuously by a plurality of Internet-connected microcontroller devices deployed at the other locations in the power system.

9. The method for real-time monitoring of a power system of claim 1 further comprising transmitting encrypted real-time impulse response data and calculated system parameter data to the monitoring station.

10. The method for real-time monitoring of a power system of claim 1 further comprising hosting the monitoring station on a central computer having a high performance computing (HPC) cluster architecture.

11. The method for real-time monitoring of a power system of claim 1 wherein the step of injecting a plurality of pseudorandom signals further comprises setting a plurality of parameters for each injected signal and initiating the injection on a cluster console.

12. The method for real-time monitoring of a power system of claim 11 wherein the plurality of parameters for each injected signal includes an injected signal magnitude, a pseudorandom sequence bit rate, and a pseudorandom sequence length.

13. The method for real-time monitoring of a power system of claim 12 further comprising displaying a cross-correlation impulse response waveform representing a continuous calculation of the cross-correlation of an injected signal with collected power system data.

14. The method for real-time monitoring of a power system of claim 13 further comprising displaying a plurality of calculated parameters associated with the cross-correlation impulse response waveform, including at least one of a total area under the response waveform, a total positive area under the response waveform, a ratio of the total positive area to the total area, a relative value of a first peak of the waveform, and a time at which the first peak occurs relative to the beginning of a pseudorandom sequence.

15. The method for real-time monitoring of a power system of claim 1 wherein the stability and security state is assessed by determination of at least one of a connectiveness between at least two selected regions of the transmission and distribution grid, a responsiveness between at least two selected regions of the transmission and distribution grid, an aggregated first peak magnitude of the impulse response waveform, and an aggregated area under the impulse response waveform for a plurality of response data collected throughout the power system.

16. A system for real-time monitoring of a power system having a plurality of locations forming a transmission and distribution grid, wherein each location includes a plurality of connected components, comprising:

a plurality of components for injecting a plurality of pseudorandom signals at selected locations in the power system;

a plurality of components for collecting a plurality of power system data at other locations in the power system in response to the injected signals;

a component for determining a dynamic behavior of the power system through a synchronized cross-correlation of the injected signals with the collected power system data;

a component for analyzing the dynamic behavior of the power system to assess a dynamic stability and security state of the power system; and

a monitoring station for displaying the real-time, dynamic stability and security state of the power system to an operator.

17. The system for real-time monitoring of a power system of claim 16 wherein the pseudorandom signals comprise pseudorandom binary noise sequences.

18. The system for real-time monitoring of a power system of claim 17 further comprising a plurality of discrete interval binary signal injectors for injecting pseudorandom binary noise sequences.

19. The system for real-time monitoring of a power system of claim 16 wherein the injecting of pseudorandom signals is synchronized with a reference time source.

20. The system for real-time monitoring of a power system of claim 16 wherein each discrete interval binary signal injector comprises a microcontroller deployed at each of the selected locations.

21. The system for real-time monitoring of a power system of claim 16 further comprising a plurality of Internet-connected microcontroller devices deployed at the other locations in the power system for continuous synchronized cross-correlation of the injected signals with the collected power system data.

22. The system for real-time monitoring of a power system of claim 16 further comprising a component for encrypting and transmitting real-time impulse response data and calculated system parameter data to the monitoring station.

23. The system for real-time monitoring of a power system of claim 16 wherein the monitoring station comprises a central computer having a high performance computing (HPC) cluster architecture.

24. The system for real-time monitoring of a power system of claim 16 further comprising a user interface for setting a plurality of parameters for each injected signal and initiating the injection of the pseudorandom signals at a selected location.

25. The system for real-time monitoring of a power system of claim 24 wherein the plurality of parameters for each injected signal includes an injected signal magnitude, a pseudorandom sequence bit rate, and a pseudorandom sequence length.

26. The system for real-time monitoring of a power system of claim 16 further comprising a component for displaying a cross-correlation impulse response waveform representing a continuous calculation of the cross-correlation of an injected signal with collected power system data.

27. The system for real-time monitoring of a power system of claim 26 further comprising a component for displaying a plurality of calculated parameters associated with the cross-correlation impulse response waveform, including at least one of a total area under the response waveform, a total positive area under the response waveform, a ratio of the positive area to the total area, a relative value of a first peak of the waveform, and a time at which the first peak occurs relative to the beginning of a pseudorandom sequence.

28. The system for real-time monitoring of a power system of claim 16 wherein the component for analyzing assesses the dynamic stability and security state by determining at least one of a connectiveness between at least two selected regions of the transmission and distribution grid, a responsiveness between at least two selected regions of the transmission and distribution grid, an aggregated first peak magnitude of the impulse response waveform, and an aggregated area under the impulse response waveform for a plurality of response data collected throughout the power system.