Automatic calibration of time keeping for utility meters

• US 6,633,825 B2
• Filed: 06/29/2001
• Issued: 10/14/2003
• Est. Priority Date: 06/29/2001
• Status: Expired due to Term

• Current Assignee: Landis and Gyr LLC (Landis+Gyr Group AG)
• Original Assignee: Siemens Power Transmission & Distribution Incorporated (Siemens AG)
• Inventors: Junker, John P., Burns, Gordon R.
• Primary Examiner(s): WACHSMAN, HAL D
• Application Number:
  US09/897,586
• Publication Number:
  US 20030004661A1
• Time in Patent Office: 837 Days
• Field of Search: 702/60-62, 702/57, 702/64, 702/65, 702/79, 702/85, 702/104, 702/106, 702/107, 702/122-126, 702/176-178, 702/183, 702/187-189, 702/198, 702/FOR.103, 702/FOR.104, 702/FOR.106, 702/FOR.111, 702/FOR.112, 702/FOR.134, 702/FOR-156, 702/FOR.170, 702/FOR.171, 702/89, 340/870.01, 340/870.02, 340/870.04, 340/870.05, 340/637, 340/657, 340/660, 705/63, 705/412, 324/74, 324/103.R, 324/116, 324/130, 324/137, 324/140.R, 324/141, 324/142, 307/125, 307/126, 700/286, 700/291, 700/293, 700/295-297
• US Class Current: 702/61
• CPC Class Codes: G01R 35/04 of instruments for measuring time integral of power or current

Abstract

An arrangement for adaptive time keeping in a utility meter includes a timing circuit and a controller. The timing circuit is operable to generate timing signals. The controller is operably coupled to the timing circuit to receive timing signals therefrom. Further, the controller is operable to: generate a first real-time value based at least in part on an externally generated first reference time value; derive a subsequent second real-time value, based at least in part on the first real-time value, the timing signals, and a timing circuit calibration value; obtain an externally generated second reference time value; determine a rate adjustment based at least in part on a difference between the second real-time value and the second reference time value; and generate a subsequent real-time value based at least in part on the timing signals, the timing circuit calibration value, and the rate adjustment.

Claims

1. A utility meter, comprising:

a) a source of commodity consumption information;

b) a timing circuit operable to generate timing signals;

c) a communication circuit operable to receive externally generated reference time values; and

d) a controller operably coupled to said source of commodity consumption information to receive commodity consumption information therefrom, operably coupled to said timing circuit to receive timing signals therefrom, and operably coupled to said communication circuit to obtain the externally generated reference time values therefrom, the controller operable to;

generate metering information based at least in part on said commodity consumption information;

generate a first real-time value based at least in part on an externally generated first reference time value;

derive a subsequent second real-time value, based at least in part on the first real-time value, the timing signals, and a calibration value;

obtain an externally generated second reference time value;

determine a rate adjustment based at least in part on a difference between said second real-time value and said second reference time value; and

generate a subsequent real-time value based at least in part on said timing signals, the calibration value, and the rate adjustment.

2. The utility meter of claim 1, wherein said source of commodity consumption information includes at least one source of electrical energy consumption information.

3. The utility meter of claim 2, wherein said timing circuit includes at least one crystal oscillator circuit.

4. The utility meter of claim 2, wherein said controller is further operable to correlate said metering information to at least one of said real-time values.

5. The utility meter of claim 2, wherein said controller is further operable to:

generate an adjusted real-time value based at least in part on a synchronization to said second reference time value; and

generate said subsequent real-time value further based at least in part on said adjusted real-time value.

6. The utility meter of claim 5, wherein said controller is further operable to:

obtain a first difference between the second real-time value and the second reference time value;

obtain a second difference between the first reference time value and the second reference time value;

determine the rate adjustment based at least in part on the first difference and the second difference.

7. The utility meter of claim 5, wherein said controller is further operable to determine the rate adjustment based at least in part on a tolerance around said difference between said second real-time value and said second reference time value.

8. The utility meter of claim 2, further comprising a communication circuit operably coupled to said controller to effectuate communications with an external device.

9. The utility meter of claim 2, wherein the controller is further operable to generate the subsequent real-time value based at least in part on said timing signals, the calibration value, and the rate adjustment by:

generating an adjusted calibration value based at least in part on the rate adjustment; and

generating the subsequent real-time value based at least in part on said timing signals and said adjusted calibration value.

10. An arrangement for adaptive time keeping in a utility meter, the arrangement comprising:

a) a timing circuit operable to generate timing signals;

b) a controller operably coupled to said timing circuit to receive timing signals therefrom, the controller operable to;

generate a first real-time value based at least in part on an externally generated first reference time value;

derive a subsequent second real-time value, based at least in part on the first real-time value, the timing signals, and a calibration value;

obtain an externally generated second reference time value;

determine a rate adjustment based at least in part on a difference between said second real-time value and said second reference time value; and

generate a subsequent real-time value based at least in part on said timing signals, the calibration value, and the rate adjustment.

11. The arrangement of claim 10, wherein said timing circuit includes at least one crystal oscillator circuit.

12. The arrangement of claim 10, wherein said controller is further operable to:

generate an adjusted real-time value based at least in part on a synchronization to said second reference time value; and

generate said subsequent real-time value further based at least in part on said adjusted real-time value.

13. The arrangement of claim 12, wherein said controller is further operable to:

obtain a first difference between the second real-time value and the second reference time value;

obtain a second difference between the first reference time value and the second reference time value;

determine the rate adjustment based at least in part on the first difference and the second difference.

14. The arrangement of claim 12, wherein said controller is further operable to determine the rate adjustment based at least in part on a tolerance around said difference between said second real-time value and said second reference time value.

15. The arrangement of claim 10, further comprising a communication circuit operably coupled to said controller to effectuate communications with an external device.

16. The arrangement of claim 10, wherein the controller is further operable to generate the subsequent real-time value based at least in part on said timing signals, the calibration value, and the rate adjustment by:

generating an adjusted calibration value based at least in part on the rate adjustment; and

generating the subsequent real-time value based at least in part on said timing signals and said adjusted calibration value.

17. A method of adaptively calibrating a real-time clock within a utility meter, the real-time clock generating real-time values based at least in part on timing signals generated by a timing circuit, the method comprising:

a) generating a first real-time value based at least in part on an externally generated first reference time value;

b) deriving a subsequent second real-time value based at least in part on the first real-time value, the timing signals, and a calibration value;

c) obtaining an externally generated second reference time value;

d) determining a rate adjustment based at least in part on a difference between said second real-time value and said second reference time value; and

e) generating a subsequent real-time value based at least in part on said timing signals, the calibration value, and the rate adjustment.

18. The method of claim 17, wherein:

step b) includes obtaining the timing signals from at least one crystal oscillator circuit.

19. The method of claim 17, wherein:

step e) includes obtaining the timing signals from at least one crystal oscillator circuit.

20. The method of claim 17, further comprising the steps of:

f) generating an adjusted real-time value based at least in part on a synchronization to said second reference time value; and

g) generating said subsequent real-time value further based at least in part on said adjusted real-time value.

21. The method of claim 20, wherein step d) includes:

obtaining a first difference between the second real-time value and the second reference-time value;

obtaining a second difference between the first reference time value and the second reference time value;

determining the rate adjustment based at least in part on the first difference and the second difference.

22. The method of claim 20, wherein step d) further includes determining the rate adjustment based at least in part on a tolerance around said difference between said second real-time value and said second reference time value.

23. The method of claim 17, wherein step c) includes effectuating communications with an external device via a communication circuit.

24. The method of claim 17, wherein step e) includes:

generating an adjusted calibration value based at least in part on the rate adjustment; and

generating the subsequent real-time value based at least in part on said timing signals and said adjusted calibration value.

25. A method of generating metering information within a utility meter, the utility meter having a source of commodity consumption information and the utility meter having a real-time clock generating real-time values based at least in part on timing signals generated by a timing circuit, the method comprising:

a) generating a first real-time value based at least in part on an externally generated first reference time value;

b) deriving a subsequent second real-time value based at least in part on the first real-time value, the timing signals, and a calibration value;

c) obtaining an externally generated second reference time value;

d) determining a rate adjustment based at least in part on a difference between said second real-time value and said second reference time value;

e) generating a subsequent real-time value based at least in part on said timing signals, the calibration value, and the rate adjustment; and

f) generating the metering information based at least in part on the commodity consumption information and said subsequent real-time value.

26. The method of claim 25, wherein said source of commodity consumption information includes at least one source of electrical energy consumption information.

27. The method of claim 26, wherein:

step b) includes obtaining the timing signals from at least one crystal oscillator circuit.

28. The method of claim 26, wherein:

step e) includes obtaining the timing signals from at least one crystal oscillator circuit.

29. The method of claim 26, further comprising the steps of:

g) generating an adjusted real-time value based at least in part on a synchronization to said second reference time value; and

h) generating said subsequent real-time value further based at least in part on said adjusted real-time value.

30. The method of claim 29, wherein step d) includes:

obtaining a first difference between the second real-time value and the second reference time value;

obtaining a second difference between the first reference time value and the second reference time value;

determining the rate adjustment based at least in part on the first difference and the second difference.

31. The method of claim 29, wherein step d) further includes determining the rate adjustment based at least in part on a tolerance around said difference between said second real-time value and said second reference time value.

32. The method of claim 26, wherein step c) includes effectuating communications with an external device via a communication circuit.

33. The method of claim 26, wherein step e) includes:

generating an adjusted calibration value based at least in part on the rate adjustment; and

generating the subsequent real-time value based at least in part on said timing signals and said adjusted calibration value.