Iron core structure and static winding equipment

Abstract

To reduce the maximum temperature rise of an iron core by reducing the magnetic flux density in the portions of iron core legs that are disadvantageous for cooling.SOLUTION: An iron core 1 has three or more block cores 10 stacked in the depth direction. A gap 13 is ensured between the block cores 10 of the leg portions 11 of the iron core 1. The gap 13 is ensured so as to have different lengths in the depth direction of the leg portion 11. The gap 13 at the center in the depth direction of the leg portion 11 is set to be longer than the gaps 13 at the front and back in the depth direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to technology for static winding devices such as transformers and reactors, and more particularly to a transformer and reactor having an iron core formed by laminating a plurality of block cores such as ferrite. [Background technology]

[0002] The iron core of a large-capacity transformer generally has a structure in which plate-shaped magnetic bodies made of, for example, ferrite cores are arranged in a frame shape and laminated in one direction (Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent application No. 12915 / 1983 [Patent Document 2] Japanese Patent Application Publication No. 5-326289 Summary of the Invention [Problem to be solved by the invention]

[0004] In the iron core 1 formed by laminating block cores 10 shown in Fig. 4, when gaps 13 are secured between the block cores 10, the width of the gaps 13 is set to be uniform across the cross section. This makes the magnetic resistance of each magnetic path at the front and rear centers in the depth direction of the leg portion 11 uniform, as shown in Fig. 2(a). Furthermore, even if gaps 13 are not secured, the magnetic resistance of these magnetic paths is uniform, so the magnetic flux density of the leg portion 11 is uniform.

[0005] However, as shown in FIG. 3(a), the temperature near the center of the leg portion 11, which is disadvantageous in terms of cooling, becomes high and a hot spot occurs.

[0006] In view of the above circumstances, an object of the present invention is to reduce the magnetic flux density in the leg portion of the iron core, which is unfavorable for cooling, thereby reducing the maximum temperature rise of the iron core. [Means for solving the problem]

[0007] Therefore, one aspect of the present invention is an iron core structure having three or more block cores stacked in the depth direction of the leg portion of the iron core, the gaps between the block cores having different lengths in the depth direction of the leg portion, and the gap between the block cores in the center in the depth direction being longer than the gaps between the block cores at the front and rear in the depth direction.

[0008] One aspect of the present invention is a static winding device having the above-described core structure. [Effects of the Invention]

[0009] According to the present invention, the magnetic flux density in the leg portion of the core, which is unfavorable for cooling, is reduced, and the maximum temperature rise of the core can be reduced. [Brief explanation of the drawings]

[0010] [Figure 1] (a) Front view of an iron core according to one embodiment of the present invention, (b) top view of the iron core, (c) side view of the iron core, (d) A-C cross-sectional view of the iron core, and (e) B-cross-sectional view of the iron core. [Figure 2] (a) Magnetic flux density distribution of a conventional iron core, (b) Magnetic flux density distribution of the iron core of the present invention. [Figure 3] (a) Temperature distribution of a conventional iron core, (b) Temperature distribution of the iron core of the present invention. [Figure 4] (a) is a front view of a conventional iron core, (b) is a top view of the iron core, and (c) is a side view of the iron core. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0012] An iron core 1 shown in FIG. 1, which is one aspect of the iron core structure of the present invention, is applied to static winding devices such as core-type or shell-type transformers and reactors.

[0013] The iron core 1 has leg portions 11 around which windings such as a primary winding and a secondary winding are wound, and a yoke portion 12 around which the windings are not wound.

[0014] The iron core 1 is made up of three or more block cores 10 stacked in the depth direction. A gap 13 is secured between the block cores 10 of the leg portion 11 of the iron core 1.

[0015] Gap 13 is ensured so that its length varies in the depth direction of leg portion 11. In particular, gap 13 is ensured in the center in the depth direction of leg portion 11 of iron core 1 where hot spots are likely to occur as shown in FIG. 3(a).

[0016] 1, the gap 13 at the center in the depth direction of the leg portion 11 is set to be longer than the gaps 13 at the front and rear in the depth direction. However, if the difference in length between the gaps 13 at the center in the depth direction and the gaps 13 at the front and rear in the depth direction becomes too large, the magnetic flux density at the front and rear in the depth direction becomes too high, which increases heat generation, and therefore the effect of reducing the magnetic flux density and temperature cannot be obtained.

[0017] According to the above-described structure of the iron core 1, by setting the length of the gap 13 at the depth center of the leg portion 11 to be greater than the length of the gap 13 at the front and rear ends in the depth direction, it is possible to reduce the magnetic flux density of the block core 10 at the depth center of the leg portion 11. This also reduces the loss density of the block core 10 at the depth center of the leg portion 11. Furthermore, although the cooling conditions for the block core 10 at the depth center of the leg portion 11 are stricter than those for the block cores 10 at the front and rear ends in the depth direction, the maximum temperature can be reduced by the above-described operation.

[0018] Specific functions and effects of the iron core 1 will be described with reference to FIGS.

[0019] 2(a) shows the magnetic flux density distribution of the conventional iron core 1, and FIG. 2(b) shows the magnetic flux density distribution of the iron core 1 of the present invention. As is clear from the comparison of the magnetic flux density distributions of the two, the structure of the iron core 1 of the present invention makes it possible to reduce the magnetic flux density of the block core 10 at the center in the depth direction of the iron core 1 compared to the conventional iron core 1, and it was shown that the loss density of the block core 10 at the center can also be reduced.

[0020] 3(a) shows the temperature distribution of a conventional core 1, and FIG. 3(b) shows the temperature distribution of the core 1 of the present invention. As is clear from the comparison of the two temperature distributions, the structure of the core 1 of the present invention makes it possible to reduce the temperature in the center of the leg portion 11, which is disadvantageous in terms of cooling, compared to the conventional core 1. In particular, it was shown that there is a temperature reduction effect when three or more block cores 10 are arranged in the depth direction of the core 1 and gaps 13 are secured near the heat spots of the leg portion 11. [Explanation of symbols]

[0021] 1...Iron core, 10...Block core, 11...Leg portion, 12...Yoke portion, 13...Gap

Claims

1. A leg portion on which a winding is wound; a yoke portion on which the winding is not wound; and Gaps are secured between the leg portion and the yoke portion and between the block cores of the leg portion, Three or more block cores of the leg portion and the yoke portion are stacked in the depth direction of the leg portion and the yoke portion, the gap between the block cores has a different length in the depth direction of the leg portion; The gap between the block cores at the center in the depth direction is longer than the gaps between the block cores at the front and rear in the depth direction. An iron core structure characterized by:

2. A static winding device having the core structure according to claim 1.

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