Pluggable high-voltage bushing and electrical device having a pluggable high-voltage bushing

Abstract

A pluggable high-voltage bushing includes an inner conductor which extends in a longitudinal direction between a high-voltage terminal and a plug-in section of the high-voltage bushing. The plug-in section is configured to plug the high-voltage bushing into a device connection part of an electrical device. An insulating body surrounds the inner conductor. The insulating body includes a textile sheet-like structure. An electrical device having the high-voltage bushing is also provided.

Claims

1. An electrical device, comprising: a fluid-tight housing having a housing cover; a pluggable high-voltage bushing having a high-voltage terminal; and a device connection part for accommodation and contact-connection of said high-voltage bushing, said device connection part having an exposed end at a height of said housing cover, and said device connection part having a fixing section connecting said device connection part to said housing cover; said high-voltage bushing including: a plug-in section configured to plug said high-voltage bushing into said device connection part, an inner conductor extending in a longitudinal direction between said high-voltage terminal and said plug-in section, and an insulating body surrounding said inner conductor, said insulating body including a textile sheet-shaped structure.

2. The electrical device according to claim 1, wherein said textile sheet-shaped structure is a non-woven fabric.

3. The electrical device according to claim 2, wherein said insulating body includes capacitive control inserts and insulating layers separating said capacitive control inserts from one another, said insulating layers are formed of said non-woven fabric, and said control inserts are disposed concentrically around said inner conductor and extend into said plug-in section.

4. The electrical device according to claim 3, wherein said non-woven fabric includes a synthetic polymer.

5. The electrical device according to claim 3, wherein said control inserts are spaced apart by a radial distance of between 1 mm and 3 mm.

6. The electrical device according to claim 5, wherein said radial distance between said control inserts has a variation of less than 0.5 mm.

7. The electrical device according to claim 5, wherein said radial distance between said control inserts has a variation of less than 0.2 mm.

8. The electrical device according to claim 1, wherein said insulating body includes a cured resin.

9. The electrical device according to claim 1, wherein the high-voltage bushing extends in a longitudinal direction over a length of 6 meters to 30 meters.

10. The electrical device according to claim 1, wherein said inner conductor has a diameter of at least 5 centimeters.

11. The electrical device according to claim 1, wherein said plug-in section includes an outer coating of a flexible insulating coating material.

12. The electrical device according to claim 1, which further comprises: a hollow locating section formed of an electrically non-conductive insulating material and extending from said fastening section into said housing; and a metallic contact part disposed at a closed and tapered end region, said metallic contact part extending through said insulating material of said locating section or prolonging said locating section in a direction of said closed and tapered end region.

13. The electrical device according to claim 12, which further comprises a winding connection line extending within said housing, said winding connection line connecting said contact part to a winding.

14. The electrical device according to claim 13, wherein said winding connection line is equipped with a current sensor.

15. The electrical device according to claim 1, wherein said device connection part has a curved outer surface disposed in said fluid-tight housing.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) The invention is described in greater detail hereinafter, with reference to FIGS. 1 to 4.

(2) FIG. 1 shows a first exemplary embodiment of a high-voltage bushing according to the invention, in a schematic cross-sectional representation;

(3) FIG. 2 shows an exemplary embodiment of an electrical device according to the invention having a high-voltage bushing according to the invention, in a schematic perspective representation;

(4) FIG. 3 shows a schematic sectional view of the plug-in section of the high-voltage bushing and of a device connection part of the electrical device according to FIG. 2;

(5) FIG. 4 shows a non-sectional side view of the device connection part, having the high-voltage bushing according to FIGS. 2 and 3.

DESCRIPTION OF THE INVENTION

(6) Specifically, FIG. 1 represents a partial section of a pluggable high-voltage bushing 1. The high-voltage bushing, in the representation according to FIG. 1, is plugged into a device connection part 2 of a high-voltage electrical device in the form of a transformer 3. The device connection part 2 is fastened to a housing wall 4. The housing wall 4 is part of a transformer housing of the transformer 3, which is filled with an insulating medium, for example insulating oil. The fastening of the device connection part to the housing is executed in an insulating medium-tight manner, such that the insulating medium cannot escape from the housing. The device connection part 2 comprises a conductive connection part 14 for the constitution of an electrical connection between the high-voltage bushing 1 and a winding of the transformer 3, which is not represented in the figure, which is arranged within the insulating oil-filled housing.

(7) The high-voltage bushing 1 comprises an inner conductor 5, which is configured as a hollow conductor of aluminum or copper. The inner conductor 5 is concentrically enclosed in an insulating body 6. The insulating body 6 comprises conductive control inserts 7a-c for capacitive field control, which are concentrically wound about the inner conductor 5. The control inserts 7a-c are separated from one another by insulating layers 8a-b of a non-woven PET fabric, which have been impregnated with resin further to the winding thereof onto the inner conductor 5. The control inserts 7a-c are arranged with a radial distance A from one another of 2 mm.

(8) The high-voltage bushing 1 further comprises a plug-in section 9 for the plugging of the high-voltage bushing 1 into the device connection part 2. The plug-in section 9 comprises a conically tapering part of the insulating body 6, and a connecting conductor section, which is welded to the inner conductor 5 in the form of a conductor bolt 10. A contact system 11 engages with the conductor bolt 10, which constitutes the electrical connection between the high-voltage bushing 1 and the transformer 3.

(9) An interspace 12 between the plug-in section 9 of the high-voltage bushing 1 and the device connection part 2 is filled with a silicone material, which dielectrically strengthens the interspace 12.

(10) FIG. 2 shows a perspective view of an exemplary embodiment of an electrical device according to the invention, which is configured here as a transformer 20. The transformer 20 comprises a housing 21, which is equipped with a cooling module 22, an expansion tank 23, an auxiliary current module 24 and high-voltage bushings 25-27. The above-mentioned components or modules are detachably connected to one another, and can thus be easily removed and transported in a mutually independent manner. For the protection of the high-voltage bushings 25-27, and of the active part of the transformer 20 which is arranged in the housing 21, i.e. a higher-voltage winding which is connected to the high-voltage bushing 25 or 26, a lower-voltage winding which is connected to the high-voltage bushing 27, and a core of the windings, diverters 28 are provided which, within their respective diverter housing, constitute a non-linear resistance which, in the event of overvoltages, switches over from a non-conductive state to a conductive state, thereby protecting components which are parallel-connected thereto.

(11) The high-voltage bushings 25-27 are once again configured as pluggable high-voltage bushings and, at their plug-in section 33 (FIG. 3), can be inserted into matching device connection parts 29 of the transformer 20. The device connection parts 29 are configured to a rotationally symmetrical design, and delimit a recess, the opening of which faces the housing cover, and is configured with a complementary shaping to the respective plug-in section of the high-voltage bushing 25-27. The device connection parts 29 are moreover fastened to the housing 21 in a fluid-tight manner, such that the interior or the oil reservoir of the single-phase transformer 20 is sealed from the external atmosphere in an insulating medium-tight, i.e. an air- and fluid-tight manner. At one closed end of the device connection part 29, a bolt, which is not visible in the figure, is held as a contact part which, when the high-voltage bushing 25, 26 or 27 is inserted into the respective device connection part 29, engages in conductive contact with an inner conductor which extends through the respective high-voltage bushing 25-27. Said bolt extends into the interior of the housing 21, i.e. into the oil reservoir thereof, where it engages in contact with a winding connection line, which thus electrically connects the device connection part 29 to the respective lower- or higher-voltage winding of the transformer 20.

(12) For the fitting and attachment of the high-voltage bushing 25, 26 or 27, each of the latter comprises a fixing terminal 30. From the fixing terminal 30, a column section 31 extends to a high-voltage terminal 32 which, in the exemplary embodiment represented in FIG. 2, is an exterior terminal.

(13) Each high-voltage bushing 25, 26 or 27 comprises an insulating body 251, through which an inner conductor 252 extends. The insulating body 251 incorporates conductive control inserts 253a-c, which are arranged concentrically around the inner conductor 252. The control inserts 253a-c are separated from one another by insulating layers of a synthetic plastic non-woven fabric. Further to the winding of the insulating layers and the control inserts around the inner conductor 252, the insulating body 251 is impregnated with resin. A number of the control inserts 253a-c extend into the plug-in section 33 of the high-voltage bushing 25. It should be observed that the number of three control inserts represented diagrammatically in FIGS. 1 and 3 is indicated by way of illustration only, and said number is naturally not restricted to three.

(14) FIG. 3 shows a sectional side view of a device connection part 29 and the high-voltage bushing 25, wherein the high-voltage bushing 25, by means of a plug-in section 33, is inserted into the device connection part 29. In the present exemplary embodiment, the remaining high-voltage bushings 26 and 27 from FIG. 2 are of identical design to the high-voltage bushing 26.

(15) It can be seen that the device connection part 29 comprises a fixing section 34, by means of which the latter is securely fastened to a cover 35 of the housing 21. Appropriate screw connections, for example, are employed for this purpose. In order to permit the insulating medium-tight fastening of the device connection part 29 to the housing 21, sealing means are provided, which are not represented in the figures.

(16) Each device connection part 29 further comprises a locating section 36, which is comprised of an electrically non-conductive material. The locating section 36 tapers to a closed end 37. At the closed end 37, the wall of the locating section 36 is penetrated by a bolt-shaped contact part 38. At the section thereof which penetrates into the interior 39 or the oil reservoir of the housing 21, the contact part 38 is connected to a winding connection line 40 and a screening cap 41, as shielding. The winding connection line 40 is further equipped with a current sensor in the form of a current converter 42 (FIG. 4). The current converter 42 is thus permanently installed in the housing, and its function is to detect an electric current flowing to or from the respective winding via the winding connection line 40.

(17) The plug-in section 33 of the high-voltage bushing 25 extends from the fixing section 34 into the locating section 36 of the device connection part 29. The plug-in section 33 is configured with complementary shaping to the locating section 36, such that said two components engage with an exact fit, and the ingress of air, or any other infiltrations, can be prevented.

(18) FIG. 4 shows a non-sectional side view of the pluggable bushing 10. In this view, the configuration of the locating section 36 and the current converter 42, and the position thereof relative to the remaining components, can be seen particularly clearly. Moreover, statements indicated with regard to FIG. 3 apply correspondingly.