High-voltage bushing and method for the production thereof

Abstract

A high-voltage bushing includes an insulating body disposed concentrically around a cylindrical winding support formed of electrically conductive material, and a sealing device for sealing a gap between the winding support and the insulating body. The sealing device includes a sealing element disposed in a circumferential sealing groove. The circumferential sealing groove is disposed in the winding support and accommodates the sealing element. A method for producing a high-voltage bushing includes placing an insulating body concentrically around a cylindrical winding support formed of electrically conductive material. The insulating body has mutually concentrically disposed insulating layers. A sealing element is introduced into a circumferential sealing groove in the winding support, and the insulating body is subsequently impregnated with a resin to seal a gap between the winding support and the insulating body.

Claims

1. A high-voltage bushing, comprising: a cylindrical winding support formed of an electrically conductive material, said cylindrical winding support having a circumferential sealing groove formed therein; an insulating body disposed concentrically around said cylindrical winding support; and a sealing device for sealing a gap occurring between said cylindrical winding support and said insulating body, said sealing device including a sealing element received in said circumferential sealing groove, and said sealing device including a sealing ring disposed concentrically relative to said sealing element.

2. The high-voltage bushing according to claim 1, wherein said sealing ring contains resin.

3. The high-voltage bushing according to claim 1, wherein said insulating body includes insulating layers disposed concentrically relative to one another, and said insulating body is impregnated with a hardenable resin.

4. The high-voltage bushing according to claim 1, wherein said sealing element contains an elastic synthetic material.

5. The high-voltage bushing according to claim 1, wherein said cylindrical winding body is a current conductor.

6. A high-voltage bushing, comprising: a cylindrical winding support formed of an electrically conductive material, said cylindrical winding support having a circumferential sealing groove formed therein, and said cylindrical winding support having circumferential grooves formed therein: an insulating body disposed concentrically around said cylindrical winding support; a sealing device for sealing a gap occurring between said cylindrical winding support and said insulating body, said sealing device including a sealing element received in said circumferential sealing groove; first and second protective elements sealing said sealing groove; said protective elements each being disposed in a respective one of said circumferential grooves formed in said cylindrical winding support; and said sealing groove being disposed axially between said first and second protective elements.

7. A method for producing a high-voltage bushing, the method comprising the following steps: forming a circumferential sealing groove in a cylindrical winding support formed of an electrically conductive material; providing an insulating body having mutually concentrically disposed insulating layers; placing the insulating body concentrically around the cylindrical winding support; inserting a sealing element into the circumferential sealing groove in the cylindrical winding support; placing a sealing ring coaxially around the sealing element; and subsequently impregnating the insulating body with a resin to seal a gap occurring between the cylindrical winding support and the insulating body.

8. A method for producing a high-voltage bushing, the method comprising the following steps: forming a circumferential sealing groove in a cylindrical winding support formed of an electrically conductive material; forming circumferential grooves in the cylindrical winding support; providing an insulating body having mutually concentrically disposed insulating layers; placing the insulating body concentrically around the cylindrical winding support; inserting a sealing element into the circumferential sealing groove in the cylindrical winding support; sealing the sealing groove by placing first and second protective elements in the respective circumferential grooves formed in the cylindrical winding support; subsequently impregnating the insulating body with a resin to seal a gap occurring between the cylindrical winding support and the insulating body; and locating the sealing groove axially between the first and second protective elements.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) The FIGURE illustrates a section of an embodiment of the high-voltage bushing 1 in accordance with the invention in a schematic cross-sectional view.

DESCRIPTION OF THE INVENTION

(2) The FIGURE illustrates a section of a high-voltage bushing 1 in cross-section. The section of the high-voltage bushing 1 illustrated in the FIGURE comprises a winding support 2 that is embodied in a cylindrical manner. The axis of symmetry of the cylindrical winding support 2 is characterized by a broken line 3. In the illustrated exemplary embodiment of the high-voltage bushing 1, the winding support 2 is simultaneously the current conductor. An insulating body 4 is arranged in a coaxial manner about the winding support 2.

(3) The insulating body 4 comprises control inserts 5 that are embodied from a conductive material, by way of example aluminum, so as to control the high-voltage bushing 1 in a capacitive manner. The control inserts 5 are arranged in a concentric manner and spaced apart from one another around the winding support 2. Wound-up layers of an electrically insulating material, preferably crepe paper, are located in a radial manner between the control inserts, as a consequence of which the insulating layers 51 are formed and arranged in a concentric manner with respect to one another and delimited by the control inserts.

(4) An intermediate region 6 between the winding support 2 and the insulating body 4 is filled with an elastic cork mass that can compensate for a radial expansion of the winding support 2 with regard to the insulating body 4.

(5) The winding support 2 comprises a seal groove 7 that is arranged in a circumferential manner in the winding support 2. A sealing element 8 in the form of an O-ring that is embodied from an elastic synthetic material is arranged in the seal groove 7. Moreover, the winding support 2 comprises a first groove 9 and a second groove 10 that are likewise arranged in a circumferential manner.

(6) The seal groove 8 is located in an axial manner between the grooves 9 and 10. A first O-ring 11 is arranged in the first groove 9 and a second O-ring 12 is arranged in the second groove 10. The first and the second O-ring 11, 12 are protective elements that protect the seal groove 7 from a liquid resin flowing in during the process of impregnating the insulating body 4. A free space remains in this manner in the seal groove 7 between the winding support 2 and the sealing element 8 so that it is possible for the elastic sealing elements 8 to deform.

(7) A sealing ring 13 is arranged in a coaxial manner around the seal groove 7. The sealing ring 13 comprises a paper-resin mixture so that the sealing ring 13 can easily bond with the insulating medium (in the present example resin) of the insulating body 4.

(8) Initially, the winding support 2 is produced during the process of producing the high-voltage bushing 1. Subsequently, the grooves 9 and 10 and also the seal groove 7 are produced in the winding support. The sealing element 8 and the protective elements or O-rings 11 and 12 are then inserted into the corresponding grooves 9, 10 in the winding support 2. The sealing ring 13 is arranged in a coaxial manner around the grooves 7, 9 and 10 and subsequently the insulating layers 51 of the insulating body are wound up together with the control inserts 5 on the winding support. Finally, the insulating body 4 is then impregnated with a liquid, hardenable resin. Once the liquid resin material has hardened, a compact bushing is produced that does not require any further processing so as to seal the gap between the winding support 2 and the insulating body 4.

LIST OF REFERENCE NUMERALS

(9) 1 High-voltage bushing 2 Winding support 3 Line 4 Insulating body 5 Control inserts 51 Insulating layers 6 Intermediate region 7 Seal groove 8 Sealing element 9 Groove 10 Groove 11 Protective element 12 Protective element