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

1-10. (canceled)

11. 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.

12. The high-voltage bushing according to claim 11, wherein said sealing device includes a sealing ring disposed concentrically relative to said sealing element.

13. The high-voltage bushing according to claim 12, wherein said sealing ring contains resin.

14. The high-voltage bushing according to claim 11, wherein said insulating body includes insulating layers disposed concentrically relative to one another, and said insulating body is impregnated with a hardenable resin.

15. The high-voltage bushing according to claim 11, wherein said sealing element contains an elastic synthetic material.

16. The high-voltage bushing according to claim 11, which further comprises: first and second protective elements sealing said sealing groove; said protective elements each being disposed in a respective circumferential groove formed in said cylindrical winding support; and said sealing groove being disposed axially between said first and second protective elements.

17. The high-voltage bushing according to claim 11, wherein said cylindrical winding body is a current conductor.

18. 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; and subsequently impregnating the insulating body with a resin to seal a gap occurring between the cylindrical winding support and the insulating body.

19. The method according to claim 18, which further comprises placing a sealing ring coaxially around the sealing element prior to the step of impregnating the insulating body.

20. The method according to claim 18, which further comprises sealing the sealing groove by placing first and second protective elements in respective circumferential grooves formed in the cylindrical winding support prior to the step of impregnating the insulating body, and locating the sealing groove axially between the first and second protective elements.

Description

[0020] The invention is explained hereinunder with reference to the exemplary embodiment illustrated in the FIGURE.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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

[0029] 1 High-voltage bushing [0030] 2 Winding support [0031] 3 Line [0032] 4 Insulating body [0033] 5 Control inserts [0034] 51 Insulating layers [0035] 6 Intermediate region [0036] 7 Seal groove [0037] 8 Sealing element [0038] 9 Groove [0039] 10 Groove [0040] 11 Protective element [0041] 12 Protective element