CURRENT SENSOR AND DEVICE FOR MEASURING AN ELECTRICAL CURRENT

• US 20170146572A1
• Filed: 11/02/2016
• Published: 05/25/2017
• Est. Priority Date: 11/23/2015
• Status: Active Grant

• Current Assignee: Schneider Electric Industries SAS (Schneider Electric SE)
• Original Assignee: Schneider Electric Industries SAS (Schneider Electric SE)
• Inventors: URANKAR, Lionel
• Granted Patent: US 10,416,196 B2
• Time in Patent Office: Days
• CPC Class Codes: G01R 15/181 using coils without a magnetic core, e.g. Rogowski coils
• CPC Class Codes: G01R 19/0092 measuring current only all subgroups of G01R19/00 take precedence
• CPC Class Codes: G01R 21/00 Arrangements for measuring electric power or power factor G01R7/12 takes precedence
• CPC Class Codes: G05B 11/01 electric
• CPC Class Codes: H02H 3/08 responsive to excess current responsive to abnormal temperature caused by excess current H02H5/04

Abstract

A current sensor of Rogowski type including two layers of coils surrounding a current conductor, each layer of coils including a plurality of windings wound on a plurality of axes forming the contour of polygons of identical forms, arranged on parallel planes, and placed facing one another such that each corner zone of the first polygon is situated facing a corresponding corner zone of the second polygon and such that, in each corner zone, turns of the winding of the first layer of coils have different orientations from those of the turns of the winding of the second layer of coils in the facing corner zone.

Claims

1. A Rogowski current sensor comprising a first layer of coils and a second layer of coils able to surround a current conductor so as to perform a measurement of a current flowing in said conductor,

the first layer of coils comprising a plurality of windings linked together, each winding having a longitudinal axis arranged in a first plane P1 and turns that are substantially perpendicular to said axis, the crossover of the axes forming corner zones corresponding to the vertices of a first polygon in said first plane,

the second layer of coils comprising a plurality of windings linked together, each winding having a longitudinal axis arranged in a second plane P2, parallel to the first plane P1, and turns that are substantially perpendicular to said axis, the crossover of the axes forming corner zones corresponding to the vertices of a second polygon in said second plane,

the first and second polygons being placed facing one another such that each corner zone of the first polygon is respectively situated facing each corresponding corner zone of the second polygon,

wherein

in each corner zone, the orientation of the turns of the winding of the first layer of coils is different from the orientation of the turns of the winding of the second layer of coils in the facing corner zone.

2. The current sensor according to claim 1, wherein each corner zone is occupied by an end of a single winding and that an end of an adjacent winding extends substantially as far as a side of the winding occupying said corner zone.

3. The current sensor according to claim 2, wherein the axis of each winding of the first layer of coils along each side of the first polygon is parallel to the axis of each facing winding of the second layer of coils along each side of the second polygon.

4. The current sensor according to claim 1, wherein the windings of the first layer of coils are linked in series and the windings of the second layer of coils are linked in series.

5. The current sensor according to claim 1, wherein the direction of coiling of the windings of the first layer of coils is reversed with respect to the direction of coiling of the windings of the second layer of coils.

6. The current sensor according to claim 1, wherein the shape of the first and second polygons is a rectangle or a square.

7. The current sensor according to claim 6, wherein each corner zone, the turns of the winding of the first layer of coils are oriented substantially at right angles with respect to the turns of the winding of the second layer of coils in the facing corner zone.

8. The current sensor according to claim 1, wherein the coils are produced according to the printed circuit technique.

9. The current sensor according to claim 1, wherein the coils are produced by depositing an electrically conducting material on an insulating support with a silk-screen printing technique.

10. The current sensor according to claim 1, wherein the coils are produced according to a three-dimensional printing technique.

11. An apparatus for measuring electrical power or energy comprising at least one current sensor linked to at least one circuit for processing the signal representative of the current flowing in at least one current conductor 10, comprising at least one current sensor 1 according to claim 1.

12. The apparatus for measuring electrical power or energy according to claim 11, wherein:

a first end of the first layer of coils is linked to a reference potential of the said measuring apparatus,

a second end of the first layer of coils is linked to a first input of an amplifier,

a first end of the second layer of coils is linked to said reference potential of said measuring apparatus and

a second end of the second layer of coils is linked to a second input of said amplifier.

13. An electrical trip unit comprising at least one current sensor 1 according to claim 1, and at least one processing circuit connected to said at least one current sensor 1 so as to receive at least one signal representative of the current flowing in at least one current conductor 10.

14. A switching device comprising an electrical trip unit according to claim 13, a mechanism for opening electrical contacts, said mechanism being linked to the trip unit so as to open the electrical contacts.