JP6552779B1 - Stationary inductor - Google Patents

Abstract

The present invention provides a stationary inductor that can easily improve electrical insulation by increasing assembly accuracy. The stationary inductor of the present invention is disposed so as to cover the iron core, the plurality of high voltage windings (8) wound concentrically around the iron core, and the high voltage winding (8), and has rigidity. A square bracket-like insulator (13a) having a double structure of an outer shell insulating portion and a flexible elastic sheet provided along the inner side of the outer shell insulating portion.

Description

  The present invention relates to the electrical insulation structure of a stationary inductor.

In recent years, with the increase in capacity and voltage of power transformers, the location conditions of power plants and substations have become stricter, and there has been a demand for compactness and low operating costs. In order to reduce the size, there is a method of reducing the size between the coaxially arranged cylindrical primary and secondary windings. However, if the dimensions between the windings are reduced, the windings are wound on the axially disposed longitudinal spacers, so the electric field is concentrated in the wedge-shaped oil gap formed between the windings and the insulating spacers However, dielectric breakdown is likely to occur.
In power transformers, which are a type of conventional static inductors, let's improve the electrical insulation by removing the wedge-shaped oil gap by placing a flexible strip-shaped insulator at the position where the wedge-shaped oil gap occurs. (See, for example, Patent Document 1).

Japanese Utility Model Publication No. 59-93116

  However, in such a static inductor, the assembly accuracy is not sufficient because the flexible strip-like insulator is assembled and configured, and it is not easy to improve the electrical insulation.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a stationary inductor that can easily improve electrical insulation by increasing the assembly accuracy.

A stationary inductor according to the present invention includes an iron core, a plurality of windings wound concentrically around the iron core, and a rigid outer shell insulating portion and outer shell that are arranged so as to cover each of the windings. A square bracket-shaped insulator having a double structure with a flexible elastic sheet provided along the inner side of the insulating portion, and an interlayer insulating spacer disposed between adjacent windings, It is characterized in that at least a part of the surface of the bracket-like insulator in contact with the interlayer insulating spacer has a corrugated shape .

  According to the stationary inductor according to the present invention, the assembly accuracy can be increased and the electrical insulation can be easily improved.

It is an example of the whole block diagram of the inner iron type transformer which concerns on Embodiment 1 of this invention. It is an example of the top view of the inner iron type transformer which concerns on Embodiment 1 of this invention. It is sectional drawing seen from the arrow direction of A of FIG. It is an example of the enlarged view of B area | region of FIG. It is an example of the perspective view which looked FIG. 4 from diagonally upper side. It is an example of the perspective view of the square bracket-like insulator used for the inner iron type transformer which concerns on Embodiment 1 of this invention. It is an example of sectional drawing of the square bracket-like insulator used for the inner iron type transformer concerning Embodiment 1 of the present invention. It is an example of the figure which has arrange | positioned the square bracket-shaped insulator used for the inner iron type transformer which concerns on Embodiment 1 of this invention on the whole. It is an example of the figure which has arrange | positioned the square bracket-shaped insulator used for the inner iron type transformer which concerns on Embodiment 2 of this invention only in part. It is the example of the figure which looked at the square bracket-shaped insulator used for the inner iron type transformer which concerns on Embodiment 3 of this invention from diagonally. It is an example of sectional drawing seen from the arrow direction of C of FIG. It is sectional drawing of the high voltage coil of another another example of the internal iron type transformer which concerns on Embodiment 3 of this invention. It is an example of the whole view of the shell type transformer concerning Embodiment 4 of the present invention. It is an example of the figure which expanded the principal part of D area | region of FIG. It is an example of the figure which expanded the principal part of E area | region of FIG. It is an example of the perspective view of the square bracket-like insulator shown by FIG. It is an example of sectional drawing of the square bracket-like insulator shown in FIG. It is an example of the figure which expanded the principal part of F area | region of FIG. FIG. 19 is another example of a perspective view of the square bracket insulating material shown in FIG. 18; FIG. 19 is another example of the cross-sectional view of the square-shaped insulator shown in FIG. 18; It is an example of the figure which has arrange | positioned the square bracket-shaped insulator used for the external iron type transformer which concerns on Embodiment 4 of this invention to the whole. It is an example of the figure which has arrange | positioned the square bracket-shaped insulator which concerns on Embodiment 5 of this invention only in part.

  The entire configuration according to Embodiment 1 of the present invention will be described. FIG. 1 is an example of an overall view of a three-phase power transformer in which an inner iron type transformer 1 which is an example of a static inductor according to Embodiment 1 of the present invention is immersed in three phases.

  As shown in FIG. 1, the inner iron type transformer 1 is a high voltage wound around the low voltage coil 4 and the low voltage coil 4 concentrically wound around the iron core 3 and the main leg of the iron core 3 as central axes. A coil 5 is provided. Further, both the low voltage coil 4 and the high voltage coil 5 are cylindrical, and they are adjacent to each other via the cylindrical inter-coil insulating plate 6 and the vertically long longitudinal insulating spacer 7. The inter-coil insulating plate 6 and the vertical insulating spacer 7 are installed to electrically insulate the low voltage coil 4 from the high voltage coil 5.

  The three-phase power transformer shown in FIG. 1 includes a tank 2, and the tank 2 is filled with an insulating oil that is an insulating medium and a cooling medium. As the insulating oil, for example, mineral oil, ester oil and silicone oil are used. The inner iron type transformer 1 including the iron core 3, the low voltage coil 4 and the high voltage coil 5 has three phases accommodated in a tank and immersed in oil.

  FIG. 2 is a top view of the inner iron type transformer 1 shown in FIG. With the iron core 3 as a central axis, a low voltage coil 4 is provided on the inner side, a high voltage coil 5 is provided on the outer side, and an inter-coil insulating plate 6 is provided between each. The longitudinal insulating spacers 7 are provided between the low voltage coil 4, the high voltage coil 5 and the inter-coil insulating plate 6 at regular intervals in the circumferential direction.

  FIG. 3 is a cross-sectional view seen from the arrow direction of A of FIG. The high voltage coil 5 includes a plurality of high voltage windings 8 and a plurality of interlayer insulating spacers 9. The high voltage winding 8 is wound concentrically around the iron core 3. Further, interlayer insulating spacers 9 are provided between the high voltage windings 8 stacked in the vertical direction in FIG. When the potential difference generated between the high-voltage windings 8 is large, a plurality of interlayer insulating spacers 9 may be installed in a stacked manner. The vertical insulating spacer 7 extends in the axial direction of the iron core and supports a plurality of high-voltage windings 8 stacked in the vertical direction via interlayer insulating spacers 9.

  Between the low voltage coil 4 and the high voltage coil 5, a cylindrical inter-coil insulating plate 6 centering on the axes of the low voltage coil 4 and the high voltage coil 5 is installed. In FIG. 3, two inter-coil insulating plates 6 are shown, but one or three or more may be installed as necessary. A vertical insulating spacer 7 is provided between each of the cylindrical low voltage coil 4, high voltage coil 5, and inter-coil insulating plate 6.

  FIG. 4 is a cross-sectional view showing a region B of FIG. 3 in an enlarged manner. The magnet wire 12 is made by covering the coil conductor 10 with an insulating paper 11. The high-voltage winding 8 is configured by multiple windings of the magnet wire 12, and FIG. 4 shows an example in which the magnet wire 12 is wound three times. Therefore, the high voltage winding 8 is shown in a horizontally long shape in the cross-sectional view of FIG. Although FIG. 3 does not show the square bracket insulating material 13a for the sake of simplicity, in reality, one square bracket insulating material 13a is inserted in the high-voltage winding 8 of one layer. That is, the high voltage coil 5 includes a plurality of high voltage windings 8 and a plurality of interlayer insulation layers inserted between a plurality of square bracket insulators 13 a covering the inner peripheral side of each high voltage winding 8 and a square bracket insulator 13 a. And a spacer 9. The detailed structure of the square bracket-like insulator 13a having a double structure will be described later.

  FIG. 5 is a perspective view of a part of the high-voltage coil 5 shown in FIG. 4 as viewed obliquely from above. A plurality of interlayer insulating spacers 9 are provided circumferentially at intervals along the entire region between square brackets 13a into which high voltage windings 8 are inserted. The space between them is a cooling medium flow path in which the cooling medium flows in the left-right direction as indicated by the arrow K in FIG. Further, the space between the inter-coil insulating plate 6 formed by the vertical insulating spacer 7 and the side surface of the square bracket shaped insulator 13a is a cooling medium in which the cooling medium flows in the vertical direction as shown by the arrow L in FIG. It is a medium flow path.

FIG. 6 is an example of a perspective view of the square bracket insulating material 13a. The inner periphery of the high-voltage winding 8 is covered from the inside over the entire periphery.
FIG. 7 is a cross-sectional view of the square bracket-like insulator 13a of FIG. 6 as seen in the circumferential direction. As shown in FIG. 7, the square bracket-like insulator 13a has a double structure of an outer shell insulating portion 14a having rigidity on the outer side and an elastic sheet 15a having flexibility on the inner side. That is, the square bracket-like insulator 13a has a double structure in which the elastic sheet 15a is provided along the inside of the outer shell insulating portion 14a in a cross sectional view.

  FIG. 8 shows a diagram in which the square bracket-like insulator 13 a is arranged in the high-voltage winding 8. Each high-voltage winding 8 is distinguished and referred to as a high-voltage winding 8a to 8g. The square bracket-like insulator 13a is disposed in the entire region of the entire circumference in the radial direction from the high-voltage windings 8a to 8g. Further, in FIG. 8, the high voltage application end 16 is at the high voltage winding 8a.

When the size between the low voltage winding constituting the low voltage coil 4 and the high voltage winding 8 constituting the high voltage coil 5 is reduced and made compact, the high voltage winding 8 is wound around the vertical insulating spacer 7 Therefore, the dimensions between the magnet wires 12 are reduced. Then, an electric field concentrates on the wedge-shaped oil gap formed between the high voltage winding 8 and the vertical insulating spacer 7, thereby causing a problem that dielectric breakdown is likely to occur.
In order to solve this problem, a square bracket-shaped insulator 13a is disposed in a wedge-shaped oil gap formed between the high-voltage winding 8 and the vertical insulating spacer 7. Since the square bracket-like insulator 13a has the elastic sheet 15a which is a flexible insulator inside, the wedge-like oil gap around the high-voltage winding 8 can be removed to improve the electrical insulation. it can. Moreover, since the outer side of the square bracket-like insulator 13a is a rigid outer shell insulating portion 14a, the shape of the inner elastic sheet 15a can be prevented from collapsing, and the assembly accuracy of the high voltage coil 5 can be improved.

Next, the relative dielectric constant will be described. Since a high voltage is applied between the low voltage winding forming the low voltage coil 4 and the high voltage winding 8 forming the high voltage coil 5, the elastic sheet 15a and the outer shell are closer to the high voltage winding 8 Three insulating layers of the insulating portion 14a and the vertical insulating spacer 7 are formed. The relative dielectric constant of the elastic sheet 15a is ε1, the relative dielectric constant of the outer shell insulating portion 14a is ε2, and the relative dielectric constant of the longitudinal insulating spacer 7 is ε3 in this order.
For example, if the relationship between the relative dielectric constant ε1 of the elastic sheet 15a and the relative dielectric constant ε2 of the outer shell insulating portion 14a is ε2 <ε1, the insulation existing outside the outer shell insulating portion 14a having a higher relative dielectric constant than the elastic sheet 15a. The electric field easily concentrates on the insulating oil of the medium. Insulating oil has a poor insulating performance compared to the outer shell insulating portion 14a, and when an electric field is concentrated on the insulating oil, dielectric breakdown is likely to occur, so that the cost reduction effect due to downsizing becomes worse. In addition, the electric field is concentrated around the high voltage winding 8 in particular. Therefore, in this embodiment, by setting ε1 <ε2, the electric field concentration in the elastic sheet 15a is suppressed and the electrical insulation of the elastic sheet 15a is improved. As mentioned above, since the value of the relative permittivity is set, the electrical insulation property of the entire transformer is improved, and the dimensions of the low voltage winding and the high voltage winding 8 are further reduced to reduce the cost of the internal iron type transformer 1 It can be. In addition, if ε1 <ε2 <ε3 in consideration of the relative permittivity of the vertical insulating spacer 7, it is possible to further improve the electrical insulation of the entire transformer.

  Next, the material used for the inner iron type transformer 1 of this embodiment and the value of each relative dielectric constant will be described. For the elastic sheet 15a, polyethylene or polyurethane which is a plastic material can be used, and the value of the relative dielectric constant ε1 is about 2.1 to 2.3. A high-density press board can be used for the outer shell insulating portion 14a, and the value of the relative permittivity ε2 is about 2.4 to 2.6. Polyester fiber can be used for the longitudinal insulating spacer 7, and the value of the relative dielectric constant ε3 is about 3.5. The inner iron type transformer 1 of the present embodiment satisfies the relationship of ε1 <ε2. Furthermore, the inner iron type transformer 1 of the present embodiment also satisfies the relationship of ε1 <ε2 <ε3. Therefore, the inner iron type transformer 1 of the present embodiment has an electrical insulation property by optimizing the relative dielectric constant in addition to the improvement of the electrical insulation property by improving the assembly accuracy by applying the square bracket-like insulator 13a. A further improvement of the has been realized.

Second Embodiment
In the first embodiment, the square bracket-like insulator 13a is disposed in the entire region of the entire periphery in the radial direction end up to the high voltage windings 8a to 8g.

  The difference between the second embodiment and the first embodiment is the point related to the arrangement of the bracket-like insulator 13a. In addition, about the structure similar to the internal iron type transformer 1 which concerns on Embodiment 1, the same code | symbol is attached | subjected and the description is not repeated.

  In the second embodiment of the present invention, as shown in FIG. 9, the square bracket-like insulator 13a is limited to the high voltage application end 16 and the high voltage windings 8a to 8c adjacent to the high voltage application end 16, and the entire circumference in the radial direction end portion. Covering.

  Since the potential distribution of the magnet wire 12 when the lightning impulse voltage penetrates is not uniform, the potential decreases and the electric field of the wedge-shaped oil gap decreases as the distance from the high voltage winding 8 near the high voltage application end 16 increases. Therefore, the required electrical insulation may be satisfied without improving the electrical insulation by inserting the bracket-like insulator 13a.

  Therefore, in Embodiment 2, the square bracket-like insulator 13a having the outer shell insulating portion 14a and the elastic sheet 15a is inserted only into the high-voltage windings 8a to 8c having a high wedge-shaped oil gap electric field.

As in the first embodiment, when the square bracket insulator 13a is disposed in the entire region of the entire circumference of the radial end of the high-voltage winding 8, the insertion time of the square bracket insulator 13a becomes long.
In the present embodiment, the square bracket shaped insulator 13a covers the entire circumference in the radial direction by limiting to the high voltage application end 16 and the high voltage windings 8a to 8c adjacent thereto. The insertion time of 13a is shortened.
As an example, the high-voltage winding 8 is limited to 8a to 8c, but the high-voltage winding 8 having a high electric field in the wedge-shaped oil gap to be covered is grasped by a prior electric field analysis. There is a need.

Third Embodiment
The difference between the first embodiment and the second embodiment in the third embodiment is the shape of the bracket-like insulator. Below, the inner iron type transformer which concerns on Embodiment 3 is demonstrated. In addition, about the structure similar to Embodiment 1 and Embodiment 2, the same code | symbol is attached | subjected and the description is not repeated.

Similar to FIG. 5, FIG. 10 is an example of a perspective view in which a part of the high voltage coil 5 according to the third embodiment of the present invention is viewed obliquely from the upper side. As shown in FIG. 10, in the shape of the square bracket insulating material 13b, the upper surface of the surface in contact with the interlayer insulating spacer 9 is corrugated and the lower surface is flat. By forming the upper surface of the square-shaped insulator 13b in a corrugated shape, a cooling medium flow path is formed between the interlayer insulating spacer 9 and the square-shaped insulator 13b, and the cooling performance of the entire transformer is improved. Note that the shape of the bracket-like insulator 13b is not limited to the shape of this example, and the same effect can be obtained as long as the cooling medium can flow smoothly.
FIG. 11 is a partial cross-sectional view of the high-voltage coil 5 as viewed from the direction of the arrow C in FIG. The vertical direction is the same as FIG. It can be seen that there is a space between the upper surface of the square bracket-like insulator 13 b and the interlayer insulating spacer 9.

  As another example, FIG. 12 shows a square bracket-like insulator 13c in which both the upper and lower surfaces in contact with the interlayer insulating spacer 9 are corrugated. Similar to FIG. 11, the cross section of a part of the high voltage coil 5 is shown. It can be seen that the space between the upper and lower surfaces of the square bracket shaped insulator 13c and the interlayer insulating spacer 9 is formed.

  In the present embodiment, the surface in contact with the interlayer insulating spacer 9 of the square bracket insulating material 13b and the square bracket insulating material 13c is formed into a corrugated shape, so that the interlayer insulating spacer 9 and the square bracket insulating material 13b A cooling medium flow path is formed in the space between the insulating material 13c, and the insulating medium and the insulating oil as the cooling medium flow so that the square insulation 13b and the square insulation 13c are cooled. Thereby, since the cooling performance as the whole transformer improves, even if it reduces the cross-sectional area of the magnet wire 12, it becomes possible to maintain the same cooling performance as before, and the cost of the transformer can be reduced. . The direction in which the cooling medium flows is the same as the arrows K and L shown in FIG.

  The square bracket-like insulator 13b and the square bracket-like insulator 13c are shown as examples of one type of corrugated shape in FIGS. 11 and 12, but only one type of shape may be used. Several types of shapes may be used.

Fourth Embodiment
In the first to third embodiments, the inner iron type transformer has been described. In the fourth embodiment, the outer iron type transformer 17 which is an example of the stationary induction device will be described. FIG. 13 is an example of an overall view of a single-phase power transformer in which the outer iron-type transformer 17 according to the fourth embodiment of the present invention is immersed in a single phase.

  As shown in FIG. 13, the outer iron type transformer 17 has the iron core 18 wound so as to be sandwiched between the low voltage coil 19 and the low voltage coils 19 wound with the iron core 18 and the iron core 18 facing outward. And a high voltage coil 20. The tank 21 is filled with insulating oil which is an insulating medium and a cooling medium. As the insulating oil, for example, mineral oil, ester oil and silicone oil are used. The iron core 18, the low pressure coil 19 and the high pressure coil 20 are accommodated in the tank 21.

  FIG. 14 is an enlarged view of a main part of the region D of FIG. 13 and shows a part of the outer iron type transformer 17. In FIG. 14, only the upper side of the iron core 18 is shown. The high voltage coil 20 includes only a plurality of high voltage windings 22 and an interlayer insulating plate 23 and an interlayer insulating spacer 24 or an interlayer insulating spacer 24 according to a potential difference generated between adjacent high voltage windings 22.

  FIG. 14 shows a case where four interlayer insulating plates 23 and eight interlayer insulating spacers 24 are installed between adjacent high-voltage windings 22. When the potential difference generated between the adjacent high-voltage windings 22a to 22d is large, a plurality of interlayer insulating plates 23 may be provided. The interlayer insulating spacer 24 has a constant interval in the circumferential direction over the entire overlapping region, between adjacent high voltage windings 22, between the high voltage windings 22 and the interlayer insulating plates 23, between adjacent interlayer insulating plates 23 Are installed. A space between adjacent interlayer insulating spacers 24 is a cooling medium flow path in which the cooling medium flows in the left-right direction.

  The low voltage coil 19 has the same configuration as the high voltage coil 20. Between the low voltage winding constituting the low voltage coil 19 and the high voltage winding 22 constituting the high voltage coil 20, an inter-coil insulating plate 25 is installed one or more. In FIG. 14, three inter-coil insulating plates 25 are provided. Between the low voltage winding and the inter-coil insulating plate 25, between the high voltage winding 22 and the inter-coil insulating plate 25, and between the adjacent inter-coil insulating plates 25, a constant interval is provided in the circumferential direction over the entire overlapping region. A plurality of inter-coil insulating spacers 26 are installed. In FIG. 14, four inter-coil insulating spacers 26 are provided. The space between the adjacent inter-coil insulating spacers 26 is a coolant flow path in which the coolant flows in the direction perpendicular to the paper surface of FIG.

  FIG. 15 is an enlarged view of a main part of region E in FIG. The magnet wire 29 is made by covering the coil conductor 27 with the insulating paper 28. The high-voltage winding 22 is configured by multiple windings of magnet wires 29. Therefore, the high voltage winding 22 is shown in a vertically long shape in FIG. Although FIG. 14 does not show the square bracket insulating material 13a for the sake of simplicity, in reality, one square bracket insulating material 13a is inserted in the high-voltage winding 22 of one layer.

FIG. 16 is a perspective view of the square bracket-like insulator 13 a inserted in the outer iron type transformer 17. Although it has the same shape as that used in the inner iron type transformer, the direction in which it is inserted is 90 degrees different.
FIG. 17 shows a cross-sectional view of the square bracket-like insulator 13a of FIG. 16 as seen in the circumferential direction. As shown in FIG. 17, the square bracket insulating material 13a has a double structure of an outer shell insulating portion 14a having rigidity on the outer side and an elastic sheet 15a having flexibility on the inner side. The square bracket-like insulator 13a has a shape that covers the inner circumference side of the high-voltage winding 22 from the inside over the entire circumference.

  FIG. 18 is an enlarged view of a main part of the region F in FIG. In the outer iron type transformer 17, the outer peripheral side of the high voltage winding 22 is also covered with a bracket-like insulator 13d. Similarly to FIG. 15, the magnet wire 29 is made by covering the coil conductor 27 with insulating paper 28. The high-voltage winding 22 is configured by multiple windings of magnet wires 29. Accordingly, the high voltage winding 22 is shown in a longitudinally elongated shape in FIG. In FIG. 14, the bracket-like insulator 13 d is not shown for the sake of brevity, but actually, one bracket-like insulator 13 d is inserted into each high-voltage winding 22. That is, the high-voltage coil 20 includes a plurality of high-voltage windings 22 and a plurality of square-bracket-shaped insulators 13a covering the inner circumferential side of the high-voltage windings 22 and a plurality of square-bracket-shaped insulation covering the outer circumferential sides of the high-voltage windings 22. It is composed of an object 13d, four interlayer insulating plates 23, and eight interlayer insulating spacers 24.

FIG. 19 is a perspective view of a square bracket-like insulator 13 d inserted so as to cover the entire outer periphery of the high-voltage winding 22 from the outside.
FIG. 20 shows a cross-sectional view of the square bracket-like insulator 13d of FIG. 19 as seen in the circumferential direction. Similar to the square-shaped insulator 13a, it has a double structure of an outer shell insulating portion 14d on the outer side and an elastic sheet 15d on the inner side. However, in order to cover the outer peripheral side of the high-voltage winding 22 from the outside, the square bracket-shaped insulator 13d is 180 degrees different from the square bracket-shaped insulator 13a in the opening direction.

FIG. 21 shows a diagram in which the square bracket insulator 13a and the square bracket insulator 13d are disposed in the high voltage winding 22. FIG. The high-voltage windings 22 are distinguished from each other and referred to as high-voltage windings 22a to 22f, respectively. The square bracket-like insulator 13a and the square bracket-like insulator 13d are disposed in the entire region of the entire circumference in the radial direction from the high-voltage windings 22a to 22f. Further, in FIG. 21, the high voltage application end 30 is located at the high voltage winding 22a.
By covering not only the inner peripheral side of the high-voltage winding 22 but also the outer peripheral side with the square bracket-like insulator 13 d, the electrical insulation can be further improved.

  In the case of the inner iron type transformer, only the case of using the square bracket-like insulator 13a covering the high voltage winding 8 from the inside was described, but the high voltage winding is also applied to the inner iron type transformer like the outer iron type transformer 17. A square bracket-like insulator 13d that covers 8 from the outside can be used. By using the square bracket-shaped insulator 13a and the square bracket-shaped insulator 13d, electrical insulation can be further improved.

Embodiment 5
In the fourth embodiment, the square bracket-like insulator 13a and the square bracket-like insulator 13d are arranged in the entire region of the entire circumference in the radial direction up to the high-voltage windings 22a to 22f.

  The difference between the fifth embodiment and the fourth embodiment is related to the arrangement of the bracket-like insulator 13a and the bracket-like insulator 13d. In addition, about the structure similar to the outer iron type transformer 17 which concerns on Embodiment 4, the same code | symbol is attached | subjected and the description is not repeated.

  In the fifth embodiment of the present invention, as shown in FIG. 21, square brackets 13a and square insulators 13d are limited to high voltage winding 22a and high voltage winding 22b adjacent to high voltage application end 30, respectively. Covering the entire circumference of the radial end.

  As shown in FIG. 22, when the square bracket insulating body 13a and the square bracket insulating body 13d are disposed in the entire region of the entire radial end of the high-voltage windings 22a to 22f, the square bracket insulating body 13a and The insertion time of the square bracket shaped insulator 13d becomes long. Since the potential distribution of the magnet wire 29 when the lightning impulse voltage penetrates is not uniform, the potential decreases as the distance from the high voltage winding 22 a near the high voltage application end 30 decreases, and a wedge oil gap around the high voltage winding 22 The electric field becomes low. In the locations where the electric field of the wedge-shaped oil gap is low, the required electrical insulation can be satisfied without the need to improve the electrical insulation by inserting the square brackets 13a and the square insulators 13d. There is.

  Therefore, as in the present embodiment, the bracket-like insulator 13a and the bracket-like insulator 13d are formed by the high-voltage winding 22a and the high-voltage winding having the high voltage application end 30 and the wedged oil gap electric field adjacent thereto. By covering the entire circumference in the radial direction by limiting it to 22b, the outer iron type transformer can be provided in which the insertion time is shortened and the assembly accuracy of the high voltage coil 20 is improved. In addition, although it was decided to cover 22a and 22b among the high voltage windings 22 as an example, the high voltage windings 22 having a high electric field of the wedge-shaped oil gap to be limited need to be grasped by the electric field analysis in advance is there.

In the first to third embodiments, an inner iron type transformer using insulating oil as a stationary inductor has been described, and in the fourth and fifth embodiments, an outer iron type transformer has been described. However, the present invention can be similarly applied to other types of stationary inductors, such as a reactor using insulating oil or insulating gas, for example, and equivalent effects can be obtained.
The embodiment disclosed this time is illustrative in all respects and does not serve as a basis for limited interpretation. Therefore, the technical scope of the present invention should not be construed only by the embodiments described, but is based on the description of the claims. Moreover, all changes within the meaning and range equivalent to the claims are included.

DESCRIPTION OF SYMBOLS 1 Inner iron type transformer 3 Iron core 7 Vertical insulation spacer 8, 8a, 8b, 8c, 8d, 8e, 8f, 8g High voltage winding 9 Interlayer insulation spacer 13a, 13b, 13c, 13d Square bracket-like insulators 14a, 14b, 14c, 14d Outer shell insulation 15a, 15b, 15c, 15d Elastic sheet 17 Outer iron type transformer 18 Iron core 22, 22a, 22b, 22c, 22d, 22e, 22f High voltage winding 24 Interlayer insulation spacer

Claims (6)

Iron core,
A plurality of windings wound concentrically around the iron core;
Square-bracket-shaped insulation having a double structure of a rigid outer shell insulating portion and a flexible elastic sheet provided along the inner side of the outer shell insulating portion, disposed so as to cover the windings, respectively. Things,
And an interlayer insulating spacer disposed between the adjacent windings.
At least a part of a surface of the square bracket-shaped insulator that is in contact with the interlayer insulating spacer has a corrugated shape.
A stationary inductor characterized by that. The static induction device according to claim 1, wherein a relative dielectric constant of the outer shell insulating portion is larger than a relative dielectric constant of the elastic sheet. A longitudinal insulating spacer that extends in the axial direction of the iron core and supports the plurality of windings;
The static induction device according to claim 2, wherein a relative dielectric constant of the vertical insulating spacer is larger than a relative dielectric constant of the outer shell insulating portion. The material of the vertical insulation spacer is polyester fiber,
The material of the outer shell insulating part is a press board,
The stationary inductor according to claim 3, wherein the elastic sheet is made of polyethylene or polyurethane. The static inductor according to any one of claims 1 to 3, wherein the square bracket insulating material is disposed so as to cover some of the plurality of windings. The stationary inductor according to any one of claims 1 to 3, wherein the square bracket-like insulator is disposed so as to cover from the inside and the outside of the winding.

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