Electric device with pressing plates for clamping a magnetizable core

Abstract

An electric device, for example a track transformer, connects to a high-voltage line. The electric device has a magnetizable core, at least one winding which is arranged in the vicinity of the core, and a housing which is filled with an insulating fluid and in which at least one winding is arranged. The core is arranged at least partly outside of the housing. In order to allow a stable mounting of a core formed of two halves, the core is arranged completely between two opposing pressing plates, between which tension elements for clamping the core extend.

Claims

1. An electric device for connection to a high-voltage line, the electric device comprising: a magnetizable core; at least one winding disposed in a vicinity of said magnetizable core; a housing filled with an insulating fluid and in which said at least one winding is disposed, wherein said magnetizable core is disposed at least partly outside said housing; tension elements; and two pressing plates, said magnetizable core is disposed completely between said two pressing plates which are situated opposite one another and between which said tension elements for clamping said magnetizable core extend.

2. The electric device according to claim 1, wherein said magnetizable core has a lower yoke, an upper yoke and core limbs which are connected to one another by means of said lower yoke and said upper yoke, wherein said upper yoke is supported at an end side against an upper pressing plate of said two pressing plates and said lower yoke is supported at an end side against a lower pressing plate of said two pressing plates.

3. An electric device for connection to a high-voltage line, the electric device comprising: a magnetizable core having a yoke; and at least one winding disposed in a vicinity of said magnetizable core; a housing filled with an insulating fluid and in which said at least one winding is disposed, wherein said magnetizable core is disposed at least partly outside said housing; tension elements; and two pressing plates, said magnetizable core is disposed completely between said two pressing plates which are situated opposite one another and between which said tension elements for clamping said magnetizable core extend, at least one of said two pressing plates having a recess formed therein for receiving said yoke of said magnetizable core.

4. The electric device according to claim 1, wherein: said at least one winding is one of at least two windings; and said magnetizable core has two core limbs which are disposed parallel to one another, wherein each of said core limbs is enclosed by said at least two windings.

5. The electric device according to claim 4, wherein said at least one winding is disposed in said housing and is clamped by means of said tension elements.

6. The electric device according to claim 5, wherein: said housing has two housing cover plates; and said at least one winding is disposed between said two housing cover plates of said housing, wherein said housing cover plates are clamped to one another by means of said tension elements.

7. The electric device according to claim 1, wherein said tension elements are threaded rods, cables, solid bars, pipes or networks of cables.

8. The electric device according to claim 1, wherein said tension elements and/or said two pressing plates are formed from an electrically non-conductive material.

9. The electric device according to claim 1, wherein at least one of said two pressing plates is formed from a plurality of parts.

10. The electric device according to claim 1, wherein said magnetizable core has two core halves which bear against one another or delimit an air gap with an aid of spacers.

11. The electric device according to claim 1, wherein said magnetizable core is a winding strip core.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) FIG. 1 shows a side view of an exemplary embodiment of the electric device according to the invention, and

(2) FIG. 2 shows a view of a detail of the mechanical frame of the electric device according to FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

(3) FIG. 1 shows a side view of an exemplary embodiment of the electric device 1 according to the invention. The electric device which is embodied as a transformer 1 has a core 2 with two core limbs 3 and 4 which each extend through one of two housings. In FIG. 1, the housings are illustrated without side walls in order to clear the view of the outer windings 5 and 6 which are arranged in the housing. The core limbs 3 and 4 are connected to one another by an upper yoke 7 and a lower yoke 8, so that a closed magnetic circuit is created. The core 2 consists of a magnetizable material, that is to say a ferromagnetic material for example, and is embodied as a so-called cut strip-wound core which has a plurality of winding or electrical strips which bear against one another. In this case, the electrical strips are, for example, grain-oriented electrical strips or electrical sheets. In a departure from this, said electrical strips consist of an amorphous material.

(4) In each housing which is illustrated without a side wall and fully surrounds the core limbs 3 and 4, the high-voltage winding 5 or 6, which can be seen from the outside, and respectively a low-voltage winding, not illustrated in the figure, are arranged concentrically in relation to one another. The concentric windings are inductively coupled to one another by the core limbs 3 and 4. The housing is filled with an insulating fluid F which serves for electrically insulating the high-voltage winding 5 and the low-voltage winding but also for cooling said windings. The high-voltage winding 5 is connected in series with the high-voltage winding 6. The same applies for the low-voltage windings which are arranged within the high-voltage windings 5, 6. In addition to the side wall, not illustrated in the figures, which is of cylindrical design and runs around the windings, the housing consists of two end-side housing cover plates 9 and 10 which are connected to the side wall, not illustrated, in a fluid-tight manner.

(5) The core 2 is arranged completely between a first pressing plate 11 and a second pressing plate 12 which are situated opposite one another and are connected to one another by tension elements 13. In the exemplary embodiment shown, the tension elements are embodied as threaded rods 13 which extend in a longitudinal direction and are provided with an external thread. Clamping nuts 14 which can be screwed onto the threaded rods 13 can then be screwed onto the respective threaded rod 13 until the core 2 which is situated between the pressing plates 11 and 12 is sufficiently fixedly clamped. Furthermore, the threaded rods 13 extend through passage holes which are provided in the housing cover plate 9 and the housing cover plate 10. Therefore, the housing cover plates 9 and 10 which are situated opposite one another can also be clamped to one another with the aid of further clamping nuts 14. In this case, the windings bear either directly or else by means of a winding ring 15 or another component against the housing cover plates 9 and 10, so that the required winding pressure is introduced into the windings owing to the clamping of the housing cover plates 9 and 10 in order to hold said windings in a stable manner in the desired position on the respective core limb 3, 4. Therefore, a holding frame is provided by the pressing plates 11, 12, the housing cover plates 9 and 10 and the tension elements 13.

(6) The holding frame allows simple, cost-effective assembly of the electric device 1 according to the invention. Furthermore, it is possible to insert cores 2 which consist of two halves. The two halves of the core 2 can bear against one another, so that a closed magnetic circuit is formed. In a departure from this, non-magnetizable spacers are provided between the core halves, which non-magnetizable spacers define an air gap between the halves.

(7) FIG. 2 shows a view of a detail of the upper first pressing plate 11. It can be seen that said pressing plate is connected to the lower pressing plate by means of a total of six threaded rods 13. In particular, it can be seen that the upper pressing plate 11 has a recess 16 which is configured with a complementary shape in relation to the outer contour of the upper yoke 7 in this region. The recess or indentation 16 simplifies assembly and increases the mechanical strength of the transformer 1.