GB2036451A

GB2036451A - A Transformer Unit

Info

Publication number: GB2036451A
Application number: GB7939056A
Authority: GB
Original assignee: Alsthom Unelec SA
Current assignee: Alstom SA
Priority date: 1978-11-15
Filing date: 1979-11-12
Publication date: 1980-06-25
Also published as: GB2036451B; FR2441937B1; FR2441937A1

Abstract

The invention relates to a compact transformer unit in which radiators (5, 51) for the oil-immersed transformer (11) are disposed on the sides of a frame (4) which surrounds the transformer (1) above its lid (2), said frame resting on said lid, with high-tension equipment (3, 6) being disposed above said lid in a compartment (40) formed by the free space surrounded by said radiators. The high-tension equipment comprises a main switch (3) with fuses, and a distribution switch (6). The radiators (5, 51) are mounted on three sides of the frame (4) and a cabinet (52) housing control equipment is mounted on the fourth side. A lower frame (9) encloses a low-tension distribution cabinet (8), Figure 3 (not shown) side by side with the transformer. The invention applies to electric power distribution installations. <IMAGE>

Description

SPECIFICATION A Transformer Unit The invention relates to a transformer unit and, more particularly, to a compact transformer unit.

In a transformer unit, the transformer is associated with high-tension and low-tension electric equipment generally disposed in cabinets or compartments which are then fixed to the transformer or to each other. The equipment therefore takes up a lot of ground space and is complex and expensive because of the connections and supports required to form structures of various configurations.

Further, transformer tanks generally include radiators on their sides. This takes up even more ground space and when conditions require the radiators to be installed underground, there arise cooling difficulties and difficulties in placing the live parts out of reach.

Preferred embodiments of the present invention produce a compact transformer unit which overcomes the above-mentioned disadvantages.

The invention provides a transformer unit comprising: -a transformer having a lid; radiator means; -high tension electric equipment including a main switch for the transformer; and -a radiator-supporting frame mounted on the transformer lid, said frame having sides which surround the space immediately above the transformer forming a compartment in which the high tension electric equipment is located, while the radiator means are disposed on at least one of the sides of the frame.

The radiators may be disposed on at least one of three sides of said compartment while the auxiliary control equipment of the high-tension equipment may be disposed on a fourth side.

High-tension fuses can be disposed between the terminals of the transformer and those of the main switch. Further, a distribution switch which connects the main switch to distribution cable may be disposed in said compartment and between said main switch and two opposite sides of the compartment.

A cover plate may be disposed on the upper part of the frame and a low-tension distribution cabinet may be placed back to back with one of the sides of the transformer in a space overhung by the frame.

A lower frame can be disposed under the lid in the line of the upper frame, between said upper frame and the ground. The lower frame may be surrounded by protective panels. The transformer and the low-tension distribution cabinet can be fixed to the lower frame.

An embodiment of the invention is described by way of example with reference to the accompanying drawings in which: -figure lisa schematic plan of the transformer unit in accordance with the invention, with the cover plate removed; -figure 2 is a schematic front view of the transformer unit with the auxiliary control equipment removed; and -figure 3 is a schematic profile with the radiator and cable removed.

In the figures, 1 designates a transformer which includes a transformer tank 10 containing an active component 11 immersed in oil 12. The tank 10 is sealed by a lid 2 which supports three high-voltage through terminals 20 connected to the lower terminals of a main three-pole highvoltage switch 3 via fuses 30.

Two channel section cross-bars 21 are fixed on the lid 2. The ends of the cross-bars support a metal frame consisting of a structure 4 formed by bars. The sides of the frame 4 extend beyond the edges of the transformer 1 and of its lid 2 around whose periphery they overhang.

Radiators 5 and 51 are fixed on the outside on three sides of the frame and are connected to the tank 10 by a rising pipe 13 and a descending pipe 14, the oil circulating by means of a thermosiphon in the direction of the arrows. A cabinet 52 for controlling the high-tension equipment is fixed inside the frame 4. The lid 2, the radiators 5 and 51 and the cabinet 52 surround a space above the transformer, said space constituting a compartment 40 which is closed at the top by a cover plate 53 fixed to the upper portion of the frame 4. The cross-bars 21 support two vertical partitions 22 which themselves act as supports for a horizontal plate 23 which carries the main switch 3. A three-pole distribution switch 6 mounted on the plate 23 is disposed in the compartment 40 and between the main switch 3 and each of the radiators 5 which are fixed on opposite sides of the frame 4.

The right-hand distribution switch is connected to a dry cable 61 which passes in front of the side facing the tank 2 and the left-hand switch is connected to another cable 62 which passes in front of the side facing the tank and including an end connector 63. The upper terminals of the main switch 3 and of the distribution switches are interconnected by sets of bars 65 and the lower terminals of the distribution switches 6 include contact pieces 60 for contact with the knife 66 of an earthing isolator switch. The auxiliary control equipment of the switches 5 and 6 and the earthing isolator switch are grouped together in the control cabinet 52.

A low-tension distribution cabinet 8 of the transformer is placed back to back with one of the sides of the transformer and under the lid 2 in a space overhung by the frame 4.

A lower frame 9 is fixed under the frame 4 which it extends towards the ground. The lower part of the frame 9 includes two cross-bars 91 fast with the transformer.

The lower frame is advantageously surrounded by protective panels which, for clearness' sake, are not shown in the figures.

If the heat to be dissipated in the transformer does not justify mounting radiators on three sides of the tank, radiators are disposed only on two sides or even only on one side.

The unit thus described constitutes a one-piece assembly which can be handled easily.

Claims

1. A transformer unit comprising: -a transformer having a lid; -a radiator means; -a high tension electric equipment including a main switch for the transformer; and -a radiator-supporting frame mounted on the transformer lid, said frame having sides which surround the space immediately above the transformer forming a compartment in which the high tension electric equipment is located, while the radiator means are disposed on at least one of the sides of the frame.

2. A transformer unit according to claim 1, wherein the radiator means are disposed on no more than three sides of said frame with the auxiliary control equipment for the high-tension electric equipment disposed on a fourth side.

3. A transformer unit according to claim 1 or 2, wherein high-tension fuses are disposed between terminals to the transformer and terminals of the main switch.

4. A transformer unit according to any preceding claim, wherein a distribution switch which connects the main switch to a distribution cable is disposed in said compartment between said main switch and two opposite sides of the compartment.

5. A transformer unit according to any preceding claim, wherein a cover plate is disposed on the upper part of the frame.

6. A transformer unit according to any preceding claim, wherein a low-tension distribution cabinet is placed back to back with one of the sides of the transformer in a space overhung by the frame.

7. A transformer unit according to any preceding claim, wherein a lower frame is disposed in line with the upper frame, between said upper frame and the ground.

8. A transformer unit according to claim 7, wherein the lower frame is surrounded by protective panels.

9. A transformer unit according to claim 7 or 8, wherein the transformer and the low-tension distribution cabinet are fast with the lower frame.

10. A transformer unit substantially as herein described with reference to and as illustrated in the accompanying drawings.