System and method for automatically determining the electrical energy service type to which an energy meter is connected

• US 6,094,622 A
• Filed: 11/30/1998
• Issued: 07/25/2000
• Est. Priority Date: 10/22/1996
• Status: Expired due to Term

• Current Assignee: Elster Electricity LLC (Honeywell International Inc.)
• Original Assignee: ABB Power T&D Limited (ABB Limited)
• Inventors: Hemminger, Rodney C., Holdsclaw, Scott T., Munday, Mark L., Hubbard, Vick A.
• Primary Examiner(s): Hoff, Marc S.
• Assistant Examiner(s): MILLER, CRAIG S
• Application Number:
  US09/201,292
• Time in Patent Office: 603 Days
• Field of Search: 702/57, 702/60, 702/61, 702/62, 702/64, 702/65, 702/79, 702/80, 702/81, 702/90, 702/189, 702/FOR 111, 324/500, 324/74, 324/76.11, 324/76.77, 324/86, 324/110
• US Class Current: 702/61
• CPC Class Codes: G01R 19/2513 Arrangements for monitoring electric power systems, e.g. power lines or loads; Logging
• CPC Class Codes: G01R 21/133 by using digital technique
• CPC Class Codes: G01R 22/00 Arrangements for measuring time integral of electric power or current, e.g. electricity meters

Abstract

A system for determining the service type to which an energy meter having meter elements is connected. The system includes a memory for storing reference information relating to different service types. The system determines which meter elements of the energy meter are active, and then determines relative phase angles and phase voltages of the meter elements. The relative phase angles are determined in to be in an ABC or a CBA rotation. Power quality monitoring is used in determining the phase voltages. The relative phase angles and phase voltages are compared to the reference information to determine the service type. The reference information includes services and scaling information, a nominal service voltage, a programmable potential indicator threshold, and a maximum and a minimum tolerance with respect to the nominal service voltage.

Claims

1. A system for determining the service type to which an energy meter having at least one meter element is connected, comprising:

storage means for storing reference information reflective of at least one service type;

means for determining which of said meter elements of said energy meter are active;

means for determining a plurality of relative phase angles of said active meter elements;

means for determining a plurality of phase voltages of said active meter elements; and

means for retrieving said reference information from said storage means and comparing said relative phase angles and said phase voltages with said reference information to determine the service type.

2. The system according to claim 1, wherein said means for determining which of said meter elements are active comprises means for determining a number of meter elements in the service type.

3. The system according to claim 1, wherein said means for determining which of said meter elements are active comprises at least one of a digital signal processor (DSP) and an analog/digital (A/D) converter.

4. The system according to claim 1, wherein said storage means comprises a memory.

5. The system according to claim 4, wherein said memory comprises an EEPROM.

6. The system according to claim 1, wherein said means for retrieving and comparing comprises a microcontroller.

7. The system according to claim 1, wherein said means for determining said phase voltages comprises power quality monitoring instrumentation.

8. The system according to claim 1, further comprising means to store the service type in said storage means.

9. The system according to claim 8, wherein said means to store the service type is one of automatic and manual.

10. The system according to claim 9, wherein said manual means to store the service type is user-activated.

11. The system according to claim 9, wherein said automatic means to store the service type is triggered when the service type is determined.

12. The system according to claim 1, wherein said storage means is programmable to change said reference information.

13. The system according to claim 12, wherein said reference information includes at least one of services and scaling information, a nominal service voltage, a programmable potential indicator threshold, and a maximum and a minimum tolerance with respect to said nominal service voltage.

14. The system according to claim 1, further comprising means for activating the system at at least one of startup and at a predetermined time during system operation.

15. The system according to claim 14, wherein said predetermined time is periodic.

16. The system according to claim 1, wherein said means for determining said relative phase angles of said meter elements comprises means for determining said relative phase angles to be one of an ABC and a CBA rotation.

17. The system according to claim 1, further comprising means for determining the number of phases present in the service type.

18. The system according to claim 1, further comprising means for displaying the service type.

19. The system according to claim 18, wherein said means for displaying the service type is an LCD display.

20. A method for determining the service type to which an energy meter having at least one meter element is connected, comprising the steps of:

storing reference information reflective of at least one service type in a memory;

determining which of said meter elements of said energy meter are active;

determining a plurality of relative phase angles of said active meter elements;

determining a plurality of phase voltages of said active meter elements;

retrieving said reference information from said memory and comparing said relative phase angles and said phase voltages with said reference information; and

determining the service type based on a result of said step of comparing.

21. The method according to claim 20, wherein said step of determining which of said meter elements are active comprises determining a number of meter elements in the service type.

22. The method according to claim 20, wherein said step of determining which of said meter elements are active comprises digital signal processing.

23. The method according to claim 20, wherein said step of determining said phase voltages comprises instrumentation measuring.

24. The method according to claim 20, further comprising the step of storing the service type in said memory.

25. The method according to claim 24, wherein said step of storing the service type in said memory is one of automatic and manual.

26. The method according to claim 25, wherein the step of storing the service type is user-activated.

27. The method according to claim 25, further comprising the step of triggering said step of storing the service type in said memory responsive to determining the service type.

28. The method according to claim 20, further comprising the step of changing said reference information.

29. The method according to claim 20, further comprising the step of activating the system at at least one of startup and at a predetermined time during system operation.

30. The method according to claim 29, wherein said predetermined time is periodic.

31. The method according to claim 20, wherein said step for determining said relative phase angles of said meter elements comprises the step of determining said relative phase angles to be one of an ABC and a CBA rotation.

32. The method according to claim 20, further comprising the step of determining the number of phases present in the service type.

33. The method according to claim 20, further comprising the step of displaying the service type.