JPH0223013B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a three-phase transformer, and particularly to the structure of a wound core transformer using thin steel strip.

[Technical Background of the Invention] Until now, the material for the wound core of transformers has been
Electric iron plates of about 0.3 to 0.35 mm were common,
Recently, amorphous magnetic materials such as amorphous amorphous have been developed with the aim of saving energy, and attempts are being made to put them into practical use in transformer wound cores.

[Problems with background technology]

However, when this amorphous magnetic material is used, the steel strip becomes thinner, about 1/10th the thickness of conventional electric iron plates, and depending on the heat treatment conditions, embrittlement occurs, making it extremely brittle. For this reason, if the structure of the conventional three-phase transformer wound core is, for example, an E-type tripod wound core, the stress distribution applied to the steel strip becomes uneven, resulting in embrittlement during operation as a transformer. This causes problems such as damage to the wound core.

[Purpose of the invention]

An object of the present invention is to provide a highly reliable three-phase transformer that prevents embrittlement of the iron core by creating a transformer structure that fully takes into account the characteristics of amorphous materials.

[Summary of the invention]

Therefore, in the present invention, a plurality of high-voltage coils and low-voltage coils are housed in a coil winding frame, and are equally distributed on the circumference of a wound core made of an amorphous magnetic material, and the weight of the core is given by the winding frame. A three-phase transformer is constructed by arranging three coils coaxially and connecting the respective coils in three phases.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the core structure of a three-phase transformer according to an embodiment of the present invention, where 1a, 1b, and 1c are three wound cores made of amorphous magnetic material. A plurality of coil winding frames 2 are equally distributed on the circumference of each of these wound cores 1a, 1b, and 1c.
Further, each of these coil winding frames 2 is wound with a high voltage coil and a low voltage coil 3. Further, the high voltage coils and the low voltage coils are connected in series in each core unit to form a single phase transformer main body. In addition, these single-phase transformer bodies have insulation spacing plates 4
A, 4b, and 4c are arranged coaxially, and each single-phase transformer main body coil is three-phase connected to form a three-phase transformer main body.

As shown in FIG. 2, in this three-phase transformer main body, a core tightening stud 5 is inserted into the center of cores a, 1b, and 1c arranged coaxially, and a stud 5 is inserted through an insulating plate 6 into a circular ring (not shown). It is tightened and fixed to the bottom of the columnar tank. Note that 7 in the figure indicates the output terminals of the high-voltage coil and the low-voltage coil attached to the insulating plate 6.

Further, as shown in the side cross-sectional view of FIG. 3, the insulating spacer plate 4 is formed into a ring shape having a spigot 8, and the coil winding frame 2 is superimposed on the spigot 8, resulting in the wound core 1a, It serves as a cradle for 1b and 1c. Furthermore, in order to improve the cooling characteristics of the coil, a comb-shaped notch 9 is provided on the outer periphery of the insulating spacer plate 4, corresponding to the coil, to increase the flow effect of the insulating oil which also serves as cooling.

Therefore, according to the above configuration, each winding core 1a,
1b and 1c are supported by the coil winding frames 2 equally spaced on their respective circumferences, so that the stress inside each wound core is equalized and fatigue failure is prevented. At this time, the core weight distributed by the coil winding frame 2 is transmitted to the insulating spacing plate 4, where it is further equalized and transmitted from the upper part to the lower part.
This prevents any imbalance in stress distribution due to the weight of the upper core in the lower core. In this way, the coil winding frame 2 not only protects the coil, which is the purpose of the main body, but also provides the effect of protecting the iron core in the case of this embodiment. In addition, these wound cores 1a, 1b, 1
c. The insulating spacing plates 4, etc. are all coaxially fixed to the bottom of the tank by the iron core tightening studs 5, and when stored inside the tank, the outer periphery of the insulating spacing plates 4 should be in close contact with the inner wall of the tank. This prevents the iron core from shifting laterally, making it structurally stable and fixed.

Furthermore, during operation as a transformer, tank insulating oil rises from the bottom of the tank up the inner diameter of the wound core and exits the topmost wound core. Here, it passes through the notch 9 on the outer periphery of the insulating spacer plate 4 again and returns to the bottom of the tank. Due to such convection of the insulating oil, the coil can be cooled well.

In addition, since the high-voltage coil and low-voltage coil are wound with uniform distribution, stray loss is reduced, and since an amorphous magnetic material is used as the winding core material, high frequency characteristics are good, and therefore high efficiency is achieved. A phase transformer is obtained.

As described above, although amorphous magnetic materials exhibit very excellent magnetic properties, they have various problems in terms of mechanical properties, making it difficult to apply them to transformers. With this configuration, it is possible to obtain a three-phase transformer that uses an amorphous magnetic material for the core and is suitable for practical use.

FIG. 4 shows another embodiment of the present invention,
In the figure, the same reference numerals as in FIG. 1 indicate the same or corresponding parts. The configuration shown in the figure differs from FIG. 1 in that a plurality of supports 10 are arranged evenly along the outer periphery of the wound cores 1a, 1b, 1c, and arms 11a, 11b, 11c are attached to the supports 10. The point is that the wound cores 1a, 1b, 1c are held by these arms instead of the insulating spacing plates 4a, 4b, 4c.

According to the above configuration, the wound cores 1a, 1b, 1c are securely fixed by the arms 11a, 11b, 11c without causing lateral displacement, and the coils are cooled well by the convection of the insulating oil.
In addition, other effects similar to those of the above-mentioned embodiments can be obtained.

Note that the wound cores 1a, 1b,
1c has an exposed core for convenience of explanation, but in reality, the outer periphery of the core is wrapped with insulating tape to form a core protective layer, or the core is hardened by coating or impregnating it with resin. death,
Of course, a protective layer is provided.

In addition, instead of the notch 9 provided on the outer circumference of the insulating spacer plate 4, the outer diameter of the insulating spacer plate 4 is made up to the bottom of the cut, and even if the position from the tank inner wall is fixed by attaching an arm, the wound iron core Needless to say, it is also effective in preventing lateral displacement of the coil, cooling the coil, etc.

〔Effect of the invention〕

As described above, according to the present invention, an amorphous magnetic material is used as the wound core material, and a plurality of coil winding frames are equally arranged on the circumference of the three wound cores, thereby producing three single-phase winding cores. By arranging these three wound cores on the same axis and connecting the coils in three phases to form a three-phase transformer, we prevent brittle fracture of the core due to the brittleness of the material. Therefore, a highly efficient three-phase transformer with excellent mechanical reliability can be obtained.

[Brief explanation of drawings]

FIG. 1 is a perspective view of the three-phase transformer main body according to an embodiment of the present invention, FIG. 2 is a perspective view of the contents of the three-phase transformer before the three-phase transformer main body of FIG. 1 is housed in a tank, and FIG. 3 is a side sectional view of the insulating spacing plate of FIG. 1, and FIG. 4 is a perspective view of the main body of a three-phase transformer according to another embodiment of the present invention. 1a to 1c...Wound core, 2...Coil winding frame, 3
... Coil, 4 ... Insulation spacing plate, 5 ... Winding core tightening stud, 6 ... Insulation plate, 7 ... Output terminal, 8
... Pilot, 9 ... Notch, 10 ... Support, 1
1a to 11c...Arm.

Claims (1)

[Scope of Claims] 1. A three-way iron core comprising three wound cores made of amorphous magnetic material equipped with a primary coil and a secondary coil, arranged coaxially, and each coil connected in three phases. phase transformer. 2. In claim 1, a winding core is formed into a circular shape, and a plurality of coil winding frames housing a primary coil and a secondary coil are arranged on the circumference of the winding core, and an insulating spacer plate is used. A three-phase transformer characterized in that three coil winding cores are arranged one on top of the other on the same axis, and each winding core is equally supported by a plurality of coil winding frames. 3. A three-phase transformer as set forth in claim 2, characterized in that, instead of the insulating spacer plates, a plurality of pillars each having a core supporting arm are arranged evenly around the outer circumference of the core. 4. In claim 2 or 3, a core tightening stud is inserted into the center of the wound core,
A three-phase transformer characterized by a wound core fastened to a tank or cover.