Metering device with control functionality and method thereof

• US 8,930,153 B2
• Filed: 03/01/2011
• Issued: 01/06/2015
• Est. Priority Date: 01/27/2005
• Status: Active Grant

• Current Assignee: EI Electronics LLC (Hubbell, Inc.)
• Original Assignee: Electro Industries/Gaugetech
• Inventors: Kagan, Erran, Banhegyesi, Tibor, Zhu, Hai
• Primary Examiner(s): COSIMANO, EDWARD R
• Application Number:
  US13/037,953
• Publication Number:
  US 20110270551A1
• Time in Patent Office: 1,407 Days
• Field of Search: 324/76.11, 324/103.R, 324/103.P, 324/115, 324/140.R, 324/140.D, 324/141, 324/142, 324/500, 324/509, 324/510, 324/511, 327/1, 327/50, 327/100, 340/500, 340/540, 340/635, 340/637, 340/638, 340/646, 340/649, 340/650, 340/652, 340/653, 340/657, 340/660, 340/662, 361/1, 361/18, 361/23, 361/30, 361/31, 361/35, 361/38, 361/42, 361/54, 361/56, 361/57, 361/62, 361/78, 361/79, 361/86, 361/87, 361/88, 361/90, 361/91.1, 361/600, 361/601, 361/602, 361/603, 361/659, 361/673, 700/1, 700/11, 700/22, 700/90, 700/286, 700/292, 700/293, 700/294, 700/297, 700/298, 702/1, 702/57, 702/58, 702/60, 702/61, 702/64, 702/127, 702/182, 702/187, 702/189, 705/400, 705/412, 708/100, 708/105, 708/200
• US Class Current: 702/64
• CPC Class Codes: G01R 15/08 Circuits for altering the measuring range
• CPC Class Codes: G01R 22/10 using digital techniques
• CPC Class Codes: G06F 11/30 Monitoring
• CPC Class Codes: G16Z 99/00 Subject matter not provided for in other main groups of this subclass

Abstract

A metering device includes a first transformer that receives an analog waveform and generates a first stepped-down output signal; a second transformer that receives the analog waveform and generates a second stepped-down output signal; first biasing circuitry that receives the first output signal from the first transformer and generates a first digital signal within a first range, wherein the first biasing circuitry includes a switching device for switching between a first and second operational sub-range; second biasing circuitry that receives the second output signal from the second transformer and generates a second digital signal within a second range; and a processor assembly in communication with the first biasing circuitry, wherein if the first digital signal saturates the first operational sub-range, the processor assembly controls the switching device to process the first output signal in the second operational sub-range.

Claims

1. A metering device operating on a secondary analog waveform output by an external transformer assembly receiving a primary waveform, the metering device comprising:

a first transformer, wherein the first transformer receives the secondary waveform and generates a first stepped-down output signal;

a second transformer, wherein the second transformer receives the secondary waveform and generates a second stepped-down output signal;

first biasing circuitry, wherein the first biasing circuitry receives the first output signal from the first transformer and generates a first digital signal within a first range, the first digital signal having a value proportional to the first output signal, wherein the first biasing circuitry includes a switching device for switching between a first and second operational sub-range;

second biasing circuitry, wherein the second biasing circuitry receives the second output signal from the second transformer and generates a second digital signal within a second range, the second digital signal having a value proportional to the second output signal; and

a processor assembly in communication with the first biasing circuitry, wherein the processor assembly executes operational software for determining if the first digital signal saturates the first operational sub-range, wherein if the first digital signal saturates the first operational sub-range, the processor assembly controls the switching device to process the first output signal in the second operational sub-range.

2. A metering device operating on a secondary analog waveform output by an external transformer assembly that receives a primary analog waveform, the metering device comprising:

a first transformer, wherein the first transformer is configured to receive the secondary analog waveform and generate a first stepped-down output signal;

a second transformer, wherein the second transformer is configured to receive the secondary analog waveform and generate a second stepped-down output signal;

first biasing circuitry in communication with the first transformer, wherein the first biasing circuitry is configured to receive the first stepped-down output signal from the first transformer and generate a first digital signal within a first range, the first digital signal having a value proportional to the first stepped-down output signal;

second biasing circuitry in communication with the second transformer, wherein the second biasing circuitry is configured to receive the second stepped-down output signal from the second transformer and generate a second digital signal within a second range, the second digital signal having a value proportional to the second stepped-down output signal; and

a processor assembly in communication with the first biasing circuitry and the second biasing circuitry, wherein the processor assembly is configured to receive the first digital signal from the first biasing circuitry and receive the second digital signal from the second biasing circuitry, and wherein the processor assembly is further configured to process the first digital signal and the second digital signal.

3. The metering device of claim 2, wherein the second biasing circuitry comprises a gain circuit and an analog-to-digital converter.

4. The metering device of claim 2, wherein the second range is at least two times greater than the first range.

5. The metering device of claim 2, wherein the first range is from about 0 Amps to about 10 Amps and the second range is from about 0 Amps to about 100 Amps.

6. The metering device of claim 2, wherein the metering device is an energy measurement device for measuring real time energy usage.

7. The metering device of claim 2, wherein the metering device is an protective relaying device for protecting equipment receiving the primary analog waveform.

8. The metering device of claim 2, wherein the first biasing circuitry comprises a switching device.

9. The metering device of claim 8, wherein the first biasing circuitry further comprises a first gain circuit in communication with the first transformer and a second gain circuit in communication with the first transformer, wherein an output from the first gain circuit is provided to a first input of the switching device and an output from the second gain circuit is provided to a second input of the switching device.

10. The metering device of claim 8, wherein the first biasing circuitry further comprises an analog-to-digital converter configured to receive an analog signal from an output of the switching device and convert the analog signal to the first digital signal within the first range.

11. The metering device of claim 8, wherein the processor assembly is configured to switch the switching device between a first operational sub-range and a second operational sub-range, wherein each of the first and second operational sub-ranges covers a portion of the first range.

12. The metering device of claim 11, wherein the second operational sub-range is at least two times greater than the first operational sub-range.

13. The metering device of claim 11, wherein the first operational sub-range is from about 1 mA RMS to about 2 Amps RMS and the second operational sub-range is from about 5 mA RMS to about 22 Amps RMS.

14. The metering device of claim 11, wherein the processor assembly is configured to determine if the first digital signal saturates the first operational sub-range, and wherein, if the processor assembly determines that the first digital signal saturates the first operational sub-range, the processor assembly controls the switching device to process the first stepped-down output signal in the second operational sub-range.

15. The metering device of claim 14, wherein the processor assembly processes the first digital signal to calculate revenue metering measurements and processes the second digital signal to capture waveform measurements.

16. The metering device of claim 11, wherein the processor assembly is configured to switch the switching device to the first operational sub-range when an input current of the first stepped-down output signal is below a predetermined switching threshold and to switch the switching device to the second operational sub-range when the input current of the first stepped-down output signal is at or above the predetermined switching threshold.

17. The metering device of claim 16, wherein the predetermined switching threshold is about 1.5 Amps RMS.

18. The metering device of claim 16, wherein the processor assembly processes the first digital signal to calculate revenue metering measurements and processes the second digital signal to capture waveform measurements.

19. The device of claim 18, wherein the processor assembly determines a need for protective measures when the captured waveform measurements exceed a predetermined range.

20. A system comprising:

a transformer assembly configured to receive a primary analog waveform and output a secondary analog waveform; and

a metering device configured to receive the secondary analog waveform from the transformer assembly;

wherein the metering device comprises;

a first transformer configured to receive the secondary analog waveform and generate a first stepped-down output signal;

a second transformer configured to receive the secondary analog waveform and generate a second stepped-down output signal;

first biasing circuitry configured to receive the first stepped-down output signal and generate a first digital signal within a first range, the first digital signal having a value proportional to the first stepped-down output signal;

second biasing circuitry configured to receive the second stepped-down output signal and generate a second digital signal within a second range, the second digital signal having a value proportional to the second stepped-down output signal; and

a processor assembly configured to receive and process the first digital signal and the second digital signal.

21. The system of claim 20, wherein the metering device is at least one of a panel metering device, a revenue metering device and a protective relaying device.

22. The system of claim 20, wherein the first biasing circuitry comprises a switching device configured to switch between a first operational sub-range and a second operational sub-range, each operational sub-range covering a portion of the first range.

23. The system of claim 22, wherein the first biasing circuitry further comprises:

a first gain circuit having a first gain;

a second gain circuit having a second gain; and

an analog-to-digital converter;

wherein an output from the first gain circuit is provided to a first input of the switching device and an output from the second gain circuit is provided to a second input of the switching device; and

wherein the analog-to-digital converter is configured to receive an analog signal from an output of the switching device and convert the analog signal to the first digital signal.

24. The system of claim 22, wherein the processor assembly is configured to switch the switching device to the first operational sub-range when an input current of the first stepped-down output signal is below a predetermined switching threshold and is configured to switch the switching device to the second operational sub-range when the input current of the first stepped-down output signal is at or above the predetermined switching threshold.

25. The system of claim 24, wherein the processor assembly of the metering device processes the first digital signal to calculate revenue metering measurements and processes the second digital signal to capture waveform measurements.

26. The system of claim 22, wherein the processor assembly is configured to determine if the first digital signal saturates the first operational sub-range and, if so, controls the switching device to process the first stepped-down output signal in the second operational sub-range.

27. The system of claim 26, wherein the processor assembly of the metering device processes the first digital signal to calculate revenue metering measurements and processes the second digital signal to capture waveform measurements.

28. A device comprising:

a first low range current measurement channel, the first low range current measurement channel including a first transformer configured to receive an analog waveform and generate a first stepped-down output signal and first circuitry configured to receive the first output signal and generate a first digital signal within a first range, the first digital signal having a value proportional to the first output signal;

a second high range current measurement channel, the second high range current measurement channel including a second transformer configured to receive the analog waveform and generate a second stepped-down output signal and second circuitry configured to receive the second output signal and generate a second digital signal within a second range, the second digital signal having a value proportional to the second output signal; and

a processor assembly in communication with the first circuitry and the second circuitry, wherein the processor assembly is configured to receive the first digital signal from the first circuitry and receive the second digital signal from the second circuitry, and wherein the processor assembly is further configured to process the first digital signal and the second digital signal.

29. The device of claim 28, wherein the first range is from about 0 Amps to about 10 Amps and the second range is from about 0 Amps to about 100 Amps.

30. The device of claim 28, wherein the first circuitry comprises a switching device.

31. The device of claim 30, wherein the processor assembly is configured to switch the switching device between a first operational sub-range and a second operational sub-range, wherein each of the first and second operational sub-ranges covers a portion of the first range.

32. The device of claim 31, wherein the second operational sub-range is at least two times greater than the first operational sub-range.

33. The device of claim 31, wherein the first operational sub-range is from about 1 mA RMS to about 2 Amps RMS and the second operational sub-range is from about 5 mA RMS to about 22 Amps RMS.

34. The device of claim 31, wherein the first circuitry further comprises a first gain circuit in communication with the first transformer and a second gain circuit in communication with the first transformer, wherein an output from the first gain circuit is provided to a first input of the switching device and an output from the second gain circuit is provided to a second input of the switching device.

35. The device of claim 31, wherein the processor assembly is configured to determine if the first digital signal saturates the first operational sub-range, and wherein, if the processor assembly determines that the first digital signal saturates the first operational sub-range, the processor assembly controls the switching device to process the first stepped-down output signal in the second operational sub-range.

36. The device of claim 35, wherein the processor assembly processes the first digital signal to calculate revenue metering measurements and processes the second digital signal to capture waveform measurements.

37. The device of claim 36, wherein the metering device is at least one of a panel metering device, a revenue metering device and a protective relaying device.

38. The device of claim 31, wherein the processor assembly is configured to switch the switching device to the first operational sub-range when an input current of the first stepped-down output signal is below a predetermined switching threshold and to switch the switching device to the second operational sub-range when the input current of the first stepped-down output signal is at or above the predetermined switching threshold.

39. The device of claim 38, wherein the predetermined switching threshold is about 1.5 Amps RMS.

40. The device of claim 38, wherein the processor assembly processes the first digital signal generated by the first low range current measurement channel to calculate revenue measurements.

41. The device of claim 38, wherein the processor assembly processes the first digital signal to calculate revenue metering measurements and processes the second digital signal to capture waveform measurements.

42. The device of claim 41, wherein the metering device is at least one of a panel metering device, a revenue metering device and a protective relaying device.

43. The device of claim 41, further comprising at least one first low range current measurement and at least one second high range current measurement channel for each phase being measured of a power distribution system.

44. The device of claim 38, wherein the processor assembly processes the second digital signal generated by the second high range current measurement channel to capture waveform measurements.

45. The device of claim 44, wherein the processor assembly determines a need for protective measures when the captured waveform measurements exceed a predetermined range.

46. The device of claim 44, wherein the processor assembly generates a control signal when the captured waveform measurements exceed a predetermined range.

47. The device of claim 46, wherein the control signal is an analog retransmit signal.

48. The device of claim 46, wherein the control signal is provided to a circuit breaker for disabling energy transmission along a selected electrical path.

49. The device of claim 46, further comprising a control device configured to receive the control signal and perform a subsequent control action on at least one external device.