Current sensor

• US 20060255793A1
• Filed: 05/10/2006
• Published: 11/16/2006
• Est. Priority Date: 05/12/2005
• Status: Active Grant

• Current Assignee: Nuvolt Corporation Inc.
• Original Assignee: Nuvolt Corporation Inc.
• Inventors: Montreuil, Michel
• Granted Patent: US 7,477,058 B2
• Time in Patent Office: Days
• US Class Current: 324/117.R
• CPC Class Codes: G01R 15/202 using Hall-effect devices Hall elements in arrangements for measuring electrical power G01R21/08
• CPC Class Codes: G01R 15/207 Constructional details independent of the type of device used
• CPC Class Codes: H01F 27/402 Association of measuring or protective means
• CPC Class Codes: H01F 3/10 Composite arrangements of magnetic circuits
• CPC Class Codes: H01F 3/14 Constrictions; Gaps, e.g. air-gaps in magnetic shunt paths H01F3/12
• CPC Class Codes: H01F 30/16 Toroidal transformers
• CPC Class Codes: H01F 38/30 Constructions
• CPC Class Codes: H01F 38/38 for polyphase ac

Abstract

The invention relates to a current sensor for monitoring electrical disturbances on an electrical circuit having an electrical conductor. The current sensor comprises a magnetic flux sensor for sensing a magnetic flux generated by a current flowing in the electrical conductor and for providing a signal representative of the current; and a processor for acquiring the signal from the magnetic flux sensor, for detecting an electrical disturbance on the current and for providing electrical disturbance data. The current sensor may also comprise a ring-shaped magnetic structure for receiving the electrical conductor and an opening within the ring-shaped magnetic structure for receiving the magnetic flux sensor. The magnetic flux sensor being for sensing a magnetic flux generated in the magnetic structure by the current in the electrical conductor.

Claims

1. A current sensor for monitoring electrical disturbances on an electrical circuit having an electrical conductor, said current sensor comprising:

a ring-shaped magnetic structure for receiving said electrical conductor whereby the magnetic structure can be positioned along said electrical conductor;

a magnetic flux sensor for sensing a magnetic flux generated in said magnetic structure by a current flowing in said electrical conductor and for providing a signal representative of said current;

said ring-shaped magnetic structure comprising an opening for receiving said magnetic flux sensor; and

a processor for acquiring said signal from said magnetic flux sensor, detecting an electrical disturbance on said current and providing electrical disturbance data.

2. The current sensor as claimed in claim 1, further comprising a printed circuit, said magnetic flux sensor and said processor being mounted thereon.

3. The current sensor as claimed in claim 1, wherein said magnetic flux sensor is further for measuring a shape and an amplitude of said current, said shape comprising a wide range of frequencies.

4. The electrical disturbance monitoring system as claimed in claim 1, wherein said processor is further for computing a leakage current from said signal.

5. The current sensor as claimed in claim 1, wherein said magnetic flux sensor comprises a hall effect sensor.

6. The current sensor as claimed in claim 1, further comprising retaining means for retaining said magnetic structure and said magnetic flux sensor around said electrical conductor.

7. The current sensor as claimed in claim 1, further comprising a voltage detector for detecting a voltage on said electrical conductor.

8. The current sensor as claimed in claim 7, wherein said voltage detector is shaped in a half moon surrounding said electrical conductor and comprises a copper trace on a substrate acting as an antenna for transmitting a voltage signal if voltage is present in said conductor, and wherein said voltage signal is received by said processor.

9. The current sensor as claimed in claim 1, wherein a diameter of said opening of said ring-shaped magnetic structure is substantially equal to a diameter of said electrical conductor.

10. The current sensor as claimed in claim 1, further comprising a case through which said electrical conductor is to be inserted for protecting said magnetic structure, said magnetic flux sensor and said processor.

11. The current sensor as claimed in claim 1, further comprising an analog to digital converter for converting said signal into a digital reading.

12. The current sensor as claimed in claim 11, further comprising an emitter for transmitting said digital reading.

13. The current sensor as claimed in claim 1, further comprising a plurality of each of said ring-shaped magnetic structure, magnetic flux sensor and opening and wherein each of said plurality is for one of a plurality of electrical conductors.

14. The current sensor as claimed In claim 13, further comprising:

a global ring-shaped magnetic structure surrounding all of said plurality of ring-shaped magnetic structure; and

a global magnetic flux sensor for evaluating a magnetic flux generated by currents flowing in all said electrical conductors;

wherein a differential reading of current flowing said plurality of electrical conductors in each conductor can be measured.

15. The current sensor as claimed in claim 13, wherein said electrical conductors comprise three line conductors and one neutral conductor.

16. A current sensor for detecting an electrical disturbance in an electrical circuit having an electrical conductor, said current sensor comprising:

a magnetic flux sensor for sensing a magnetic flux generated by a current flowing in said electrical conductor and providing a signal representative of said current; and

a processor for acquiring said signal from said magnetic flux sensor, detecting said electrical disturbance on said current and for providing an electrical disturbance signal.

17. The current sensor as claimed in claim 16, further comprising an electrical switch for disconnecting said electrical conductor in response to said electrical disturbance signal and thereby protecting said electrical circuit from being damaged.

18. The current sensor as claimed in claim 16, further comprising a printed circuit, said magnetic flux sensor and said processor being mounted thereon.

19. The current sensor as claimed in claim 16, wherein said processor Is further for computing a leakage current from said signal.

20. The current sensor as claimed in claim 16, wherein said magnetic flux sensor Is further for measuring a shape and an amplitude of said current, said shape comprising a wide range of frequencies.

21. The current sensor as claimed in claim 16, wherein said magnetic flux sensor comprises a hall effect sensor.

22. The current sensor as claimed in claim 16, further comprising a voltage detector for detecting a voltage on said electrical conductor.

23. The current sensor as claimed in claim 16, further comprising an analog to digital converter for converting said signal into a digital reading.

24. The current sensor as claimed in claim 23, further comprising an emitter for transmitting said digital reading.

25. The current sensor as claimed in claim 16, further comprising a plurality of said magnetic flux sensor, each of said plurality being for one of a plurality of electrical conductors.

26. The current sensor as claimed in claim 25, wherein said electrical conductors are a line conductors and a neutral conductor.

27. An electrical disturbance monitoring system, comprising:

a plurality of current sensors each associated with an electrical conductor and an identifier, each having a magnetic flux sensor for sensing a magnetic flux generated by a current flowing in said electrical conductor and for providing a signal representative of said current; and

a processor for acquiring said signal from said magnetic flux sensor, for detecting an electrical disturbance on said current and for providing electrical disturbance data;

a networking module for combining data provided by said plurality of current sensors; and

a processing module for receiving and for analyzing the combined data, for monitoring and for locating, using said identifier, said electrical disturbance and for alerting in case of abnormal situations.

28. The electrical disturbance monitoring system as claimed in claim 27, further comprising a user interface for extracting and for displaying electrical disturbance data and for initiating a command in reaction to said electrical disturbance.

29. The electrical disturbance monitoring system as claimed In claim 27, wherein each one of said current sensor is associated with a plurality of electrical conductors.

30. The electrical disturbance monitoring system as claimed in claim 27, wherein said processor is further for computing a leakage current from said signal.

31. The electrical disturbance monitoring system as claimed in claim 27, wherein said magnetic flux sensor is further for measuring a shape and an amplitude of said current, said shape comprising a wide range of frequencies.

32. The electrical disturbance monitoring system as claimed in claim 27, wherein each one of said current sensor further has a ring-shaped magnetic structure for receiving said electrical conductor whereby the magnetic structure can be positioned along said electrical conductor and an opening within said ring-shaped magnetic structure for receiving said magnetic flux sensor, said magnetic flux sensor for measuring said magnetic flux in said magnetic structure.

33. A current sensor, comprising:

a ring-shaped magnetic structure for receiving an electrical conductor whereby the magnetic structure can be positioned along said electrical conductor;

a magnetic flux sensor for evaluating a magnetic flux generated by a current flowing in said electrical conductor;

an opening within said ring-shaped magnetic structure for receiving said magnetic flux sensor;

a data acquisition module for receiving a reading from said magnetic flux sensor concerning said current.

34. The current sensor as claimed in claim 33, wherein said magnetic flux sensor is a hall effect sensor.

35. The current sensor as claimed in claim 33, further comprising retaining means for retaining said magnetic structure and said magnetic flux sensor around said electrical conductor.

36. The current sensor as claimed in claim 33, further comprising a voltage detector for detecting a voltage of said electrical conductor.

37. The current sensor as claimed in claim 36, wherein said voltage detector is shaped in a half moon surrounding said electrical conductor and is a copper trace on a substrate acting as an antenna transmitting a voltage signal if voltage is present in said conductor, and wherein said voltage signal is received by said data acquisition module.

38. The current sensor as claimed in claim 33, wherein a diameter of said opening of said ring-shaped magnetic structure is substantially equal to a diameter of said electrical conductor.

39. The current sensor as claimed in claim 33, further comprising a case through which said electrical conductor can be inserted for protecting said magnetic structure, said magnetic flux sensor and said data acquisition module.

40. The current sensor as claimed in claim 33, further comprising an analog to digital converter for converting a reading received by said data acquisition module into a digital reading.

41. The current sensor as claimed in claim 40, further comprising an emitter for transmitting said digital reading.

42. The current sensor as claimed in claim 33, further comprising a plurality of each of said ring-shaped magnetic structure, magnetic flux sensor and opening and wherein each of said plurality is for one of a plurality of electrical conductors.

43. The current sensor as claimed in claim 42, further comprising:

a global ring-shaped magnetic structure surrounding all of said plurality of ring-shaped magnetic structure; and

a global magnetic flux sensor for evaluating a magnetic flux generated by currents flowing in all said electrical conductors;

wherein a differential reading of current flowing said plurality of electrical conductors can be measured.

44. The current sensor as claimed in claim 43, wherein said global magnetic flux sensor is a hall effect sensor.

45. The current sensor as claimed in claim 43, further comprising retaining means for retaining said global magnetic structure and said global magnetic flux sensor around said plurality of magnetic structures.

46. The current sensor as claimed In claim 42, wherein said plurality is four.

47. The current sensor as claimed in claim 46, wherein said electrical conductors are three line conductors and one neutral conductor.