JPS5910735Y2 - Conductor connection structure of large current transformer - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a large current transformer, and particularly to a connection structure for a conductor connecting a coil and a bushing.

In high current transformers, the connection between the coil and the bushing is usually made using strip-shaped conductors arranged in parallel.

This conductor is firmly held through an insulator because it produces an attraction or repulsion effect due to electromagnetic mechanical force.

Furthermore, the conductor connections are designed to be tightened with the tightening pressure necessary to pass a large current.

Figure 1 shows one end of the coil connected to the rectifier by a bushing 4 (omitted in Figure 2) attached to the long side of the tank at the center of the height of the coil, and the other end attached to the short side of the tank as a neutral point. This shows a conventional example of a rectifier transformer connected to a bushing 13, and FIG. 2 shows a front view of the inside.

1 is a tank with the part to which the short side neutral point bushing is attached protruding from the side, 2 is a coil, 3 is a clamp, 4 is a bushing connected to a rectifier, 5 is a rising conductor connected to coil 2, 6 is a flexible conductor that connects the rising B conductor 5 and the bushing 4.

The neutral point is connected to the main conductor 11.12 by riser conductors 7, 8, connecting pieces 9, 10 and to the neutral point bushing 13 by a flexible conductor 6'.

In this case, the main conductors 11, 12 are held in a suitable position by means of a retaining member 14 so as to withstand the mechanical forces mentioned above.

Since the end connected to the flexible conductor 6' is unstable in a state close to a free end, it is held by a holding member 14.

FIG. 3 is a sectional view showing the holding structure, and 14 is the main conductor 1.
1.12 is a spacing insulator that insulates between the main conductors 11.
12 indicates an insulator that insulates the insulating stud 16, nut 17, washer, etc., and the main conductor 11.12 indicates the insulating stud 16.
, a nut 17, a dust metal 18, and a spring washer 19 are tightened through each insulator 14, 15.

In a transformer with such a structure, tank 1 is
The problem is that the protruding portion 1a is required, which increases the oil amount and weight, and also increases the external dimensions of the tank 1.

Therefore, a structure in which the dimension A of the tank protruding portion 1a is reduced has been desired.

Fig. 4 shows a structure for reducing the tank protruding portion 1a.
The one shown in FIG. 5 is known.

FIG. 4 is a cross-sectional view of the main part of the tightening structure, and FIG. 5 is a top view of the protruding portion of the tank, which allows electrical connection and spacing to be maintained at the same time.

That is, there is a gap insulator 20 between the main conductors 11' and 12'.
and insert the insulating stud 2 through the insulator 20.
2. When tightening the nut 23, washer 24, and spring washer 25, the connecting piece 10' and the main conductor 12' are tightened at the same time.

If such a tightening structure is used for a long period of time, there is a risk that the contact pressure at the connection portion will decrease due to the spacing insulator 20 drying out.

For this reason, it is necessary to increase the area of the conductor connection so that there is no problem even if the contact pressure decreases due to drying out, but this will require a large tightening stud, so if the main conductor is not too short. The effect contributing to the A' dimension is also small.

The present invention has been made in view of the above, and it is an object of the present invention to provide a conductive connection structure for a large current transformer that does not reduce the contact pressure of the conductor contact portion due to withering of the spacer insulator, etc.

The present invention will be described below with reference to an embodiment shown in FIGS. 6 and 7.

Incidentally, the same parts as in the prior art are denoted by the same reference numerals, and the explanation thereof will be omitted.

At the connecting part between one of the plurality of main conductors 31 and 32 and the connecting piece 10 closest to the neutral point bushing 13 side connected to this, both sides of the connecting part are attached as shown in FIG. Insulating stud 3 with a threaded part that allows you to tighten the nut with
4 and tighten both with a nut 17, washer 18, and spring washer 19.

A nut 17 is inserted between the main conductor 32 and the other main conductor 31 on the inside.
, an insulator 33 with a gap larger than the outer diameter of the washer 18 is inserted, and an insulator 15 is interposed on the outside of the main conductor 31,
These are inserted into the aforementioned insulating studs 34.

A nut 17, a washer 18, and a spring washer 19 are attached to the outside of the insulator 15 to tighten the main conductors 31 and 32.

In this structure, the conductor connection part is the insulating stud 34 and nut} 1
7.17 and is tightened in the same way as bolts and nuts.

Furthermore, the holding between the main conductors 31 and 32 can also be carried out at the same position as this conductor connection.

Therefore, the dimension a of the tank protrusion 1a' can be reduced.

As described above, the present invention has the advantage that the tank is small, the amount of oil and weight are reduced, and the external dimensions can be reduced.

[Brief explanation of the drawing]

Figure 1 is a plan view showing the structure of a conventional large current transformer;
The figure is a front view showing only the upper part of the large current transformer in Figure 1, Figure 3 is a sectional view showing the main conductor holding structure, and Figure 4 is a conventional holding structure that connects and holds the conductor at the same time. 5 is a sectional view showing the structure, FIG. 5 is a plan view of FIG. 4, FIG. 6 is a plan view showing an embodiment of the present invention, FIG. 7 is a front view showing only the upper part of FIG. FIG. 8 is an enlarged cross-sectional view of the conductor connection portion shown in FIG. 6, and FIG. 9 is a perspective view showing an example of the spacing insulator used in the present invention. 1'...Tank, 1a'...Protrusion,
2... Coil, 3... Clamp, 4.
...Bushing connected to the rectifier, 5, 7.8.
...Rising conductor, 6,6'...Flexible conductor, 9,10.10'...Connection piece, 31.32.
... Main conductor, 13 ... Neutral point bushing, 15 ... Insulator, 33 ... Spacing insulator, 34 ... Insulation stud .

Claims (1)

[Scope of utility model registration request] Connect multiple neutral point rising conductors led out from the coil to multiple main conductors arranged on the top of the coil through connection pieces, and attach one end of the above multiple main conductors to the tank. In a high current transformer connected to a neutral point bushing, an insulating stud is provided that penetrates at least the connection piece of the neutral point rising conductor located on the neutral point bushing side and the plurality of main conductors, and the connection The piece and one of the main conductors are connected by tightening with a plurality of nuts screwed onto the insulating stud, and a spacing insulator is interposed between the plurality of main conductors, and the insulating stud is connected to the outside of the other main conductor. A conductor connection structure for a large current transformer characterized by tightening multiple main conductors with nuts that are screwed together.