Solid dielectric encapsulated interrupter with reduced corona levels and improved BIL

• US 7,148,441 B2
• Filed: 04/19/2005
• Issued: 12/12/2006
• Est. Priority Date: 09/30/2002
• Status: Expired due to Term

• Current Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Original Assignee: Mcgraw-Edison Company (Eaton Corporation PLC.)
• Inventors: Stoving, Paul N., Potter, Mike E., Daharsh, Ross S., Bestel, E. Fred
• Primary Examiner(s): Enad, Elvin
• Assistant Examiner(s): FISHMAN, MARINA
• Application Number:
  US11/108,856
• Publication Number:
  US 20060231529A1
• Time in Patent Office: 602 Days
• Field of Search: 218/136, 218/137, 218/155, 218/134, 218118-121, 218/10, 218/77, 174/142, 174/144, 174/137.R, 174/140.R
• US Class Current: 218/136
• CPC Class Codes: H01C 7/12 Overvoltage protection resistors series resistors structurally associated with spark gaps H01T1/16
• CPC Class Codes: H01H 2033/6623 Details relating to the encasing or the outside layers of the vacuum switch housings
• CPC Class Codes: H01H 2033/6667 Details concerning lever type driving rod arrangements
• CPC Class Codes: H01H 33/027 Integrated apparatus for measuring current or voltage
• CPC Class Codes: H01H 33/24 Means for preventing discharge to non-current-carrying parts, e.g. using corona ring
• CPC Class Codes: H01H 33/6606 Terminal arrangements
• CPC Class Codes: H01H 33/662 Housings or protective screens

Abstract

A current interrupter assembly includes an insulating structure, a current interrupter embedded in the structure, a conductor element embedded in the structure, a current interchange embedded in the structure and connected to create a current path between the current interrupter and the conductor element, and a semiconductive layer covering at least a portion of the conductor element so as to reduce voltage discharge between the conductor element and the structure.

Claims

1. A current interrupter assembly comprising:

a molded unitary insulating structure;

a cavity;

a current interrupter embedded in the molded structure;

a conductor element embedded in the molded structure;

a current interchange embedded in the molded structure and connected to create a current path between the current interrupter and the conductor element; and

a conductive shield embedded in the molded structure, positioned in a semiconductive layer, and configured to decrease voltage discharges in a cavity in the structure,

wherein the semiconductive layer is at least partially embedded in the molded structure.

2. The assembly of claim 1 wherein the voltage discharges are due to high voltage stress caused by close proximity between one or more high-potential elements and a low-potential element.

3. The assembly of claim 2 wherein the high-potential elements include the current interrupter, the current interchange, and the conductor element.

4. The assembly of claim 1 wherein the semiconductive layer is a partially conductive rubber with a resistivity on the order of one ohm-meter.

5. The assembly of claim 1 wherein the current interrupter comprises a vacuum interrupter.

6. The assembly of claim 1 wherein the current interchange element includes at least a first end and a second end disposed on an axis with the first end being configured to electrically connect to the current interrupter, and the conductive shield being configured to extend from the current interchange past the second end.

7. The assembly of claim 6 wherein the conductive shield is configured to be substantially parallel with the axis.

8. The assembly of claim 6 wherein the current interchange has an outer surface disposed between the first end and the second end and the conductive shield overlaps a portion of the outer surface.

9. The assembly of claim 6 wherein the current interchange has a dimension equal to a distance traveled around a perimeter of an outer surface of the current interchange relative to the axis and the shield extends less than the dimension.

10. The assembly of claim 6 wherein the current interchange has one or more sides that form an outer surface that is disposed between the first end and the second end, the outer surface having a perimeter dimension relative to the axis equal to the distance around the perimeter of the outer surface, and the shield being configured to surround less than the perimeter dimension.

11. The assembly of claim 1 wherein the shield comprises aluminum.

12. The assembly of claim 1 wherein the shield comprises a mesh.

13. The assembly of claim 1 further comprising a semiconductive layer positioned between the conductor element and the structure so as to cover at least a portion of the conductor element and to reduce voltage discharges between the conductor element and the structure.

14. The assembly of claim 1 wherein the shield comprises the same material as the semiconductive layer.

15. The assembly of claim 1 wherein the shield comprises a conductive or nonconductive material coated with a semiconductive paint.

16. The assembly of claim 1 wherein the shield comprises a conductive or nonconductive material wrapped in a semiconductive tape.