Current sensing devices and methods

• US 9,304,149 B2
• Filed: 03/12/2013
• Issued: 04/05/2016
• Est. Priority Date: 05/31/2012
• Status: Active Grant

• Current Assignee: Pulse Electronics Incorporated (Yageo Corporation)
• Original Assignee: Pulse Electronics Incorporated (Yageo Corporation)
• Inventors: Lint, James Douglas, Jin, Fuxue, Aldaco, Victor, Machado, Russell L.
• Primary Examiner(s): Nguyen, Vinh
• Application Number:
  US13/797,575
• Publication Number:
  US 20130320961A1
• Time in Patent Office: 1,120 Days
• Field of Search: 324/76.11, 324/76.39, 324/76.75, 324/150, 324/654, 324/522, 324/536, 324/127
• US Class Current: 1/1
• CPC Class Codes: G01R 15/181 using coils without a magnetic core, e.g. Rogowski coils
• CPC Class Codes: G01R 31/28 Testing of electronic circuits, e.g. by signal tracer EMC, EMP or similar testing of electronic circuits G01R31/002; testing for short-circuits, discontinuities, leakage or incorrect line connection G01R31/50; checking computers or computer components G06F11/00; checking static stores for correct operation G11C29/00 ; testing receivers or transmitters of transmission systems H04B17/00
• CPC Class Codes: G06Q 30/04 Billing or invoicing
• CPC Class Codes: G06Q 50/06 Energy or water supply

Abstract

A low-cost and high-precision current sensing device and methods for use and manufacturing. In one embodiment, the current sensing apparatus comprises a Rogowski-type coil which is manufactured in segments so as to facilitate the manufacturing process. In an exemplary embodiment, the current sensing apparatus segments are asymmetric in shape and/or composition (e.g., bobbin shape, size, and/or winding configuration) so as to account for asymmetries in the magnetic field distribution around a bus bar, or to accommodate its shape in a more compact form factor, and/or to improve the immunity to the effects of an external magnetic field. Methods of manufacturing and using the aforementioned current sensing apparatus are also disclosed.

Claims

1. A current sensing inductive device, comprising:

a plurality of coil-like sensing elements; and

a hinged housing having both an open and a closed form, the hinged housing having an aperture associated therewith, the hinged housing further configured to articulate about a hinge;

wherein the hinged housing comprises one or more snap features disposed at a perimeter region thereof external to the aperture, the one or more snap features configured to maintain the hinged housing in the closed form; and

wherein the one or more snap features are disposed on an opposing side of the aperture with respect to the hinge.

2. The device of claim 1, wherein the plurality of coil-like sensing elements are collectively configured to be disposed in a predefined position relative to a sensed structure via one or more bus bar retaining elements when the hinged housing is in the closed form.

3. The device of claim 2, wherein the sensed structure comprises a bus conductor associated with one phase of a multiple-phase electrical system.

4. The device of claim 2, wherein the predefined position comprises positioning the sensed structure in a plane that bisects the housing in two portions of approximately equal size.

5. The device of claim 4, wherein the predefined position further comprises positioning the sensed structure in a plane that is centered on an interface between two adjacently disposed coil-like sensing elements.

6. The device of claim 5, wherein the one or more bus bar retaining elements receives the sensed structure at only the ends of the sensed structure.

7. A current sensing inductive device, comprising:

a plurality of coil-like sensing elements; and

a hinged housing having both an open and a closed form, the hinged housing having an aperture associated therewith, the hinged housing further configured to articulate about a hinge;

wherein the hinged housing comprises a snap feature disposed at a perimeter region thereof external to the aperture, the snap feature configured to maintain the hinged housing in the closed form;

wherein the hinge is disposed between two adjacently disposed coil-like sensing elements; and

wherein the snap feature is disposed between two other adjacently disposed coil-like sensing elements.

8. The device of claim 7, wherein the plurality of coil-like sensing elements are collectively configured to be disposed in a predefined position relative to a sensed structure via one or more bus bar retaining elements when the hinged housing is in the closed form.

9. The device of claim 8, wherein the sensed structure comprises a bus conductor associated with one phase of a multiple-phase electrical system.

10. The device of claim 8, wherein the predefined position comprises positioning the sensed structure in a plane that bisects the housing in two portions of approximately equal size.

11. The device of claim 10, wherein the predefined position further comprises positioning the sensed structure in a plane that is centered on an interface between two adjacently disposed coil-like sensing elements.

12. The device of claim 11, wherein the one or more bus bar retaining elements receives the sensed structure at only the ends of the sensed structure.

13. A current sensing inductive device, comprising:

a plurality of coil-like sensing elements; and

a housing comprising at least an open and a closed form, the at least a portion of the housing being configured to articulate about a hinge, the housing further comprising;

a substantially circular aperture comprising a plurality of recesses configured to place a sensed element in a predefined position; and

a snap feature disposed at a perimeter region of the housing and configured to maintain the housing in the closed form;

wherein;

the snap feature is disposed on the housing substantially opposite from the hinge and across the substantially circular aperture;

the hinge is disposed proximate a junction of first and second adjacently disposed coil-like sensing elements; and

the snap feature is disposed proximate a junction of third and fourth adjacently disposed coil-like sensing elements.

14. The device of claim 13, wherein the sensed element comprises a bus conductor associated with one phase of a multiple-phase electrical system.

15. The device of claim 13, wherein the closed form is configured to enhance current-sensing sensitivity.

16. The device of claim 13, wherein the closed form is configured to reduce cross-phase interference.

17. The device of claim 13, wherein the predefined position comprises a position of the sensed element in a plane that bisects the housing into two portions of approximately equal size.

18. The device of claim 13, wherein the predefined position comprises a position of the sensed element in a plane that bisects the housing, and the plane is centered on an interface between the two adjacent coil-like sensing elements.

19. The device of claim 13, wherein the substantially circular aperture receives the sensed element only at ends of the sensed element.

20. The device of claim 13, wherein the device comprises an odd number of coil-like sensing elements.