TRANSFORMER WITH INSERTABLE HIGH VOLTAGE CONDUCTOR

Abstract

An electrical appliance for connection to a high-voltage network has a housing that is fillable with an insulating liquid, in which housing a core with at least one winding is arranged, and a bushing plug-in socket fixed to the housing and a high-voltage bushing insertable into the bushing plug-in socket. The electrical appliance is also able to be used at higher voltages, in that the high-voltage bushing has a fixing section, with which the high-voltage bushing can be fixed to the housing and/or to the bushing plug-in socket and from which the high-voltage bushing extends with a column section in a longitudinal direction over a length L2 towards a high-voltage terminal. The length L2 is greater than three meters.

Claims

1-6 (canceled)

7. An electrical appliance for connection to a high-voltage network, the electrical appliance comprising: a housing to be filled with insulating liquid, and a core with at least one winding disposed in said housing; a bushing plug-in socket fixed to said housing; and a high-voltage bushing configured for insertion into said bushing plug-in socket, said high-voltage bushing including a fixing section for affixing said high-voltage bushing to one or both of said housing or said bushing plug-in socket and a column section extending from said fixing section in a longitudinal direction over a length L2 towards a high-voltage terminal, said length L2 being greater than three meters.

8. The electrical appliance according to claim 7, wherein said high-voltage bushing, introduced into said bushing plug-in socket, extends with a plug-in section in the longitudinal direction into said bushing plug-in socket over a length L1, said length L1 being less than 600 mm.

9. The electrical appliance according to claim 7, wherein said bushing plug-in socket comprises a fixing section for fixing to said housing, a hollow receiving section made of an electrically non-conductive insulating material extends from said fixing section into said housing, wherein a metallic contact part is disposed at a closed tapered end region, and said metallic contact part extends through said insulating material of said receiving section or lengthening said receiving section to said closed end region.

10. The electrical appliance according to claim 9, which comprises a winding connecting line extending inside said housing and connecting said contact part to said at least one winding of said core.

11. The electrical appliance according to claim 10, wherein said winding connecting line is provided with a current transformer.

12. The electrical appliance according to claim 7, wherein said plug-in section of said high-voltage bushing comprises a sheathing of a viscous insulator, and wherein a high-voltage conducting element extends through said sheathing at a free end of said plug-in section.

13. The electrical appliance according to claim 7, wherein said bushing plug-in socket is one of three bushing plug-in sockets fixed to said housing and said high-voltage bushing is one of three high-voltage bushings each configured for insertion into a respective one of said three bushing plug-in sockets.

Description

[0012] Further expedient embodiments and advantages of the invention are the subject-matter of the following description of examples of embodiment making reference to the figures, wherein identical reference numbers relate to identically acting components and wherein

[0013] FIG. 1 shows an example of embodiment of the electrical appliance according to the invention in a perspective representation,

[0014] FIG. 2 shows the housing of the electrical appliance according to FIG. 1 in plan view,

[0015] FIG. 3 shows a cross-sectional view of the plug-in section and of the plug-in socket including a shield,

[0016] FIG. 4 shows a side view, not cut away, of the plug-in socket with a high voltage conductor and a current transformer,

[0017] FIG. 5 shows the housing according to FIG. 2 in a side view with introduced high voltage conductors,

[0018] FIG. 6 shows the plug-in section of the high voltage conductor and the fixing section and

[0019] FIG. 7 shows an example of embodiment of the conductor plug-in socket in a view from above.

[0020] FIG. 1 shows, in a perspective view, an example of embodiment of the electrical appliance according to the invention, which is constituted here as a transformer 1. Transformer 1 shown there comprises a housing 2, which is provided with a cooling module 3, an expansion vessel 4, an auxiliary current module 5 and high voltage conductors 6, 7, 8. The known components or modules are connected detachably to one another, so that they can easily be dismantled and transported independently of one another. For the protection of high voltage conductors 6, 7 and 8 and the active part of the transformer arranged in the housing, i.e. the high voltage winding connected to high voltage conductor 6 or 7 and the low voltage winding connected to high voltage conductor 8 and the core, the limbs whereof are surrounded by the respective windings, use is made of arresters 9, which inside their arrester housing comprise a non-linear resistor, which in the event of overvoltages switches from a non-conducting state into a conducting state and thus protects the components connected to it in parallel.

[0021] High voltage conductors 6, 7 and 8 are each constituted as insertable high voltage conductors and can be introduced with their plug-in end into matching conductor plug-in sockets 10. Conductor plug-in sockets 10 are constituted rotation-symmetrical and border a cavity lying open towards the housing cover but closed at one side, said cavity being constituted with a complementary shape to the plug-in section of respective high voltage conductor 6, 7, 8. Conductor plug-in sockets 10 are also fixed fluid-tight to housing 2, so that the internal space or oil chamber of single-phase transformer 1 is sealed hermetically, i.e. air- and liquid-tight, from the external atmosphere. Held at the closed end of the conductor plug-in socket is a conductor stud (not shown in the figures) as a contact part which, when high voltage conductor 6, 7 or 8 is introduced into respective conductor plug-in socket 10, is in conductive contact with the high-voltage conducting element extending through respective high voltage conductor 6, 7, 8. Said conductor stud extends into the interior of housing 2, i.e. into its oil chamber, where it is in contact with a winding connecting line, which thus connects the conductor plug-in socket electrically to the respective high or low voltage winding of transformer 1.

[0022] For the assembly and fixing of high voltage conductor 6, 7 or 8, the latter each comprise a fixing connection 11. A column section 12 extends from fixing connection 11 to a high-voltage terminal 13, which in the example of embodiment shown is an outdoor connection.

[0023] FIG. 2 shows housing 2 of transformer 1 according to FIG. 1 in plan view. In this view, it can be seen that housing 2 comprises three plug-in sockets 10, which in FIG. 2 are all closed fluid-tight with a cover. Fluid-tight is understood here to mean that the cover closes the openings air- and liquid-tight by means of suitable sealing means.

[0024] FIG. 3 shows a conductor plug-in socket 10 and a high voltage conductor 8 in a sectional side view, wherein high voltage conductor 8 is introduced with a plug-in section 22 into conductor plug-in socket 10. It can be seen that conductor plug-in socket 10 comprises a fixing section 14, with which said conductor plug-in socket is mounted fixedly on a cover 15 of housing 2. Suitable screw-type connections, for example, are used for this purpose. In order to fix conductor plug-in socket 10 to housing 2 in an air- and liquid-tight manner, sealing means (not represented in the figures) are required, which are clamped between cover 15 and fixing section 14 constituted as a flange.

[0025] Each conductor plug-in socket 10 further comprises a receiving section 16, which is made of an electrically non-conductive material. Receiving section 16 tapers towards a closed end 17. At closed end 17, the wall of receiving section 16 is penetrated by a stud-shaped contact part 18. At its section projecting into interior space 19 or the oil chamber of housing 2, contact part 18 is connected to a winding connecting line 20 and a spherical shielding cap 21 as a shield. Winding connecting line 20 is also provided with a current transformer 26, which is shown in FIG. 4. Current transformer 26 is thus fixedly installed in the housing and serves to detect an electrical current flowing via winding connecting line 20 to or from the respective winding.

[0026] Plug-in section 22 extends from fixing section 11 of high voltage conductor 8 into receiving section 16 of conductor plug-in socket 10. Plug-in section 22 is constituted with a complementary shape to receiving section 16, so that the two components lie with a perfect fit against one another and air or other inclusions can be prevented. The distance between the fixing section and the free end of high voltage conductor 8 is denoted as L1.

[0027] s FIG. 4 shows conductor plug-in socket 10 in a side view not cut away. In this view, the embodiment of receiving section 16 and of current transformer 26 and its position relative to the remaining components can be seen particularly well. Moreover, the comments made in respect of FIG. 3 apply here correspondingly.

[0028] FIG. 5 shows housing 2 of transformer 1 according to FIG. 1 in a side view. In this view, the two high voltage conductors 6 and 8 can be seen, which are inserted into their assigned conductor plug-in sockets 10. In particular, it can be seen that column section 12 extends over a length L2, which according to the invention is greater than 3 meters, so that high voltage conductors 6, 8 are equipped for sufficiently high voltages and have a sufficiently high dielectric strength.

[0029] FIG. 6 illustrates plug-in section 22 of high voltage conductor 8 by way of example for all high voltage conductors 6, 7, 8 in a side view. In this view, it can in particular be seen that high voltage conductor 8 comprises a high-voltage conducting element 24, which extends from high-voltage terminal 13 at the other free end of high voltage conductor 8 through the entire insulating body of high voltage conductor 8. In an inserted position, high-voltage conducting element 24 enters at its lower end 26 into contact with contact part 18 of conductor plug-in socket 10. Moreover, fixing section 11 of high voltage conductor 8 is sketched in rough outline, being constituted as a flange in the shown example of embodiment. Flange 11 can be connected rigidly by a screw-type connection to housing cover 15. Distance L1 between lower end 26 and fixing section 11 is advantageously less than 600 mm.

[0030] Plug-in section 22 comprises a sheathing 25 of a viscous insulator, which closes off plug-in section 22 to the exterior, wherein high-voltage conducting element 24 alone projects out of sheathing 25. Once plug-in section 22 has been introduced, the viscous insulator of sheathing 25 lies adjacent to the inner side of receiving section 16, wherein viscous sheathing 25 fills free spaces between the plug-in socket and the plug-in section of the high voltage conductor, so that air inclusions and therefore high electrical field strengths are prevented.

[0031] FIG. 6 shows rotation-symmetrical plug-in socket 10 from above. In this view, housing cover 15 and fixing section 14 of plug-in socket 10, in particular, can be seen particularly well. Fixing section 14 is again constituted as a standard flange connection, wherein it can also be seen that receiving section 16 extends from fixing section 14 downwards, i.e. into oil chamber or internal space 19, wherein receiving section 16 tapers towards a closed end. Contact part 18 can be seen at the closed end. Contact part 18 is constituted as a sleeve and thus closed at one side. The internal diameter of sleeve 18 is somewhat greater than the external diameter of conducting element 24, wherein spring-loaded contact finders provide a sufficiently good electrical contact. Receiving section 16 comprises a wall made of an insulating material, which is not electrically conductive. During operation, contact part 18 is at a high-voltage potential, wherein housing 2 and therefore also housing cover 15 and fixing section 14 are at earth potential.