Systems and methods for real-time protective device evaluation in an electrical power distribution system

• US 20070213956A1
• Filed: 03/12/2007
• Published: 09/13/2007
• Est. Priority Date: 03/10/2006
• Status: Active Grant

• Current Assignee: Bentley Systems Incorporated
• Original Assignee: EDSA Micro Corporation (PAC Global, Inc.)
• Inventors: Nasle, Adib, Nasle, Ali
• Granted Patent: US 7,844,439 B2
• Time in Patent Office: Days
• US Class Current: 702/182
• CPC Class Codes: G06F 2111/02 CAD in a network environment, e.g. collaborative CAD or distributed simulation
• CPC Class Codes: G06F 2119/06 Power analysis or power optimisation
• CPC Class Codes: G06F 30/20 Design optimisation, verification or simulation optimisation, verification or simulation of circuit designs G06F30/30
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y04S 40/20 Information technology specific aspects, e.g. CAD, simulation, modelling, system security

Abstract

A system for providing real-time modeling of protective device in an electrical system under management is disclosed. The system includes a data acquisition component, a virtual system modeling engine, and an analytics engine. The data acquisition component is communicatively connected to a sensor configured to provide real-time measurements of data output from protective devices within the system under management. The virtual system modeling engine is configured to update a virtual mode of the system based on the status of the protective devices and to generate predicted data for the system using the updated virtual model. The analytics engine is communicatively connected to the data acquisition system and the virtual system modeling engine and is configured to monitor and analyze a difference between the real-time data output and the predicted data output. The analytics engine is also configured to determine the bracing capabilities for the protective devices.

Claims

1. A method for determining in real-time the bracing capability of a protective device in a monitored system using a virtual model, comprising:

receiving real-time sensor data for the monitored system including for the protective device;

generating predicted operational values for the monitored system including for the protective device;

performing a short circuit analysis for the protective device using the predicted operational values;

calculating a adjusted short circuit current for the protective device;

determining a device rating for the protective device; and

determining whether the device rating is greater than or equal to the adjusted short circuit current.

2. The method of claim 1, further comprising determining if there is a change in status for the protective device based on the real-time sensor data, and when it is determined that there is a change in status, then updating the virtual model accordingly.

3. The method of claim 2, wherein the change in status can be related to the open/close status.

4. The method of claim 2, wherein the change in status can be related to the source and load status.

5. The method of claim 2, wherein the change in status can be related to the on/off status.

6. The method of claim 1, further comprising determining whether the protective device passes or fails based on whether the device rating is greater than or equal to the adjusted short circuit current.

7. The method of claim 6, further comprising determining the percent rating for the protective device.

8. The method of claim 1, wherein performing a short circuit analysis for the protective device comprises calculating a symmetrical short circuit current for the protective device.

9. The method of claim 8, wherein the device is a fuse or switch, the method further comprising determining an asymmetrical short circuit current, instead of the adjusted short circuit current, based on the symmetrical short circuit current, and determining whether the device rating is greater than or equal to the asymmetrical short circuit current.

10. The method of claim 8, wherein the device is a fuse or a switch, and wherein determining the adjusted short circuit current comprises:

calculating an inductance/reactance (X/R) ratio for the fuse or switch;

determining if the calculated X/R is greater than a test X/R; and

when it is determined that the calculated X/R is not greater than the test X/R, then setting the adjusted short circuit current equal to the symmetrical short circuit current.

11. The method of claim 10, further comprising, when it is determined that the calculated X/R is greater than the test X/R, then calculating the adjusted short circuit current based on the symmetrical short circuit current, the calculated X/R, and the test X/R.

12. The method of claim 8, wherein the device is a Low Voltage Circuit Breaker (LVCB), and wherein determining the adjusted short circuit current comprises determining whether the LVCB is fused.

13. The method of claim 12, further comprising, when it is determined that the device is not fused, determining whether the device is an instantaneous trip device.

14. The method of claim 13, further comprising, when it is determined that the device is an instantaneous trip device, then calculating a first cycle fault X/R and determining whether the first cycle fault X/R is greater than a circuit breaker test X/R.

15. The method of claim 14, further comprising, when it is determined that the first cycle fault X/R is not greater than a circuit breaker test X/R, then determining whether the LVCB is peak rated.

16. The method of claim 15, further comprising, when it is determined that the LVCB is not peak rated, then setting the adjusted short circuit current equal to the symmetrical short circuit current.

17. The method of claim 15, further comprising, when it is determined that the LVCB is peak rated, then determining whether the device rating is greater than or equal to the symmetrical short circuit current instead of determining whether the device rating is greater than or equal to the adjusted short circuit current.

18. The method of claim 14, further comprising, when it is determined that the first cycle fault X/R cycle fault X/R is greater than a circuit breaker test X/R, then determining whether the LVCB is peak rated.

19. The method of claim 18, further comprising, when it is determined that the LVCB is not peak rated, then calculating the adjusted short circuit current based on the symmetrical short circuit current, the calculated X/R, and the test X/R.

20. The method of claim 18, further comprising, when it is determined that the LVCB is peak rated, then calculating a peak current for the LVCB and determining whether the device rating is greater than or equal to the peak current instead of determining whether the device rating is greater than or equal to the adjusted short circuit current.

21. The method of claim 13, further comprising, when it is determined that the device is not instantaneous trip device, then calculating a time delayed fault X/R and determining whether the time delayed fault X/R is greater than a circuit breaker test X/R.

22. The method of claim 21, further comprising, when it is determined that the time delayed fault X/R is not greater than a circuit breaker test X/R, then setting the adjusted short circuit current equal to the symmetrical short circuit current.

23. The method of claim 21, further comprising, when it is determined that the time delayed fault X/R is greater than a circuit breaker test X/R, then calculating a delayed short circuit current and determining whether the device rating is greater than or equal to the delayed short circuit current instead of determining whether the device rating is greater than or equal to the adjusted short circuit current.

24. The method of claim 12, further comprising, when it is determined that the device is fused, then calculating a fault X/R and determining whether the fault X/R is greater than a circuit breaker test X/R.

25. The method of claim 24, further comprising, when it is determined that the fault X/R is greater than a circuit breaker test X/R, then calculating the adjusted short circuit current based on the symmetrical short circuit current, the calculated X/R, and the test X/R.

26. The method of claim 24, further comprising, when it is determined that the fault X/R is not greater than a circuit breaker test X/R, then setting the adjusted short circuit current equal to the symmetrical short circuit current.

27. The method of claim 1, wherein the protective device is a High Voltage Circuit Breaker (HVCB), the method further comprising calculating a peak current for the HVCB and determining whether the device rating is greater than or equal to the peak current instead of determining whether the device rating is greater than or equal to the adjusted short circuit current.

28. The method of claim 1, wherein the protective device is a High Voltage Circuit Breaker (HVCB), the method further comprising calculating an interrupting time for the HVCB.

29. The method of claim 28, further comprising calculating a fault X/R and determining whether the fault X/R is greater than a circuit breaker test X/R.

30. The method of claim 29, further comprising, when it is determined that the fault X/R is not greater than a circuit breaker test X/R, then setting the adjusted short circuit current equal to the symmetrical short circuit current.

31. The method of claim 29, further comprising, when it is determined that the fault X/R is greater than a circuit breaker test X/R, then determining a contact breaking time for the HVCB.

32. The method of claim 31, further comprising calculating the adjusted short circuit current based on the symmetrical short circuit current, the calculated X/R, and the test X/R.