CN120826749A - Shell-type transformer - Google Patents

Abstract

A shell-type transformer has a plurality of insulating plates (140) located between adjacent ones of a plurality of planar windings (130). The plurality of insulators includes a plurality of first insulators and at least one second insulator in contact with the at least one planar winding (130) at a position closer to the core (110) than the plurality of first insulators. The at least one second insulator is composed of a material having a lower dielectric constant than the plurality of first insulators.

Description

Shell type transformer

Technical Field

The present disclosure relates to a shell type transformer.

Background

As a prior art document for disclosing the structure of an oil-immersed transformer, japanese patent application laid-open No. 3-12410 (patent document 1) exists. The oil immersed transformer described in patent document 1 has an oil pipe through which insulating oil circulates around windings to cool the windings. As the insulating material for the conduit member and the vertical wedge which are disposed in the region where the sharing voltage is high and which constitute the oil pipe, a low dielectric constant material having a relative dielectric constant of 4.0 or less is used.

Prior art literature

Patent literature

Patent document 1 Japanese unexamined patent publication No. 3-12410

Disclosure of Invention

Technical problem to be solved by the invention

Low dielectric constant materials are relatively expensive, and therefore, if the entire catheter member is composed of low dielectric constant materials, the device cost increases.

The present disclosure has been made in view of the above-described problems, and an object thereof is to provide a shell-type transformer in which a low dielectric constant material is used only in an insulating member adjacent to a portion where a high electric field is generated in a planar winding, thereby improving insulation reliability while suppressing an increase in device cost.

Technical proposal adopted for solving the technical problems

A shell-type transformer based on the present disclosure includes an iron core, a plurality of planar windings, a plurality of insulating plates, and a plurality of insulators. The plurality of flat windings are arranged in an axial direction of the core and wound around the core. The plurality of insulating plates are arranged along the axial direction and are positioned between adjacent ones of the plurality of flat windings. The plurality of insulators are in contact with at least one of the plurality of planar windings. The plurality of insulators includes a plurality of first insulators and at least one second insulator in contact with the at least one planar winding at a position closer to the core than the plurality of first insulators. The at least one second insulator is made of a material having a lower dielectric constant than the plurality of first insulators.

Effects of the invention

According to the present disclosure, a low dielectric constant material is used only in an insulating member adjacent to a portion where a high electric field is generated in a planar winding, so that insulation reliability can be improved while suppressing an increase in device cost.

Drawings

Fig. 1 is a perspective view showing the structure of a shell-type transformer according to an embodiment.

Fig. 2 is an exploded perspective view showing a structure of a winding group included in a shell-type transformer according to an embodiment.

Fig. 3 is a longitudinal sectional view of a part of a shell-type transformer according to an embodiment.

Detailed Description

Hereinafter, a shell-type transformer according to an embodiment will be described with reference to the drawings. In the following description of the embodiments, the same or corresponding portions in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated.

Fig. 1 is a perspective view showing the structure of a shell-type transformer according to an embodiment. Fig. 2 is an exploded perspective view showing a structure of a winding group included in a shell-type transformer according to an embodiment. Fig. 3 is a longitudinal sectional view of a part of a shell-type transformer according to an embodiment. In fig. 1 to 3, the case is not illustrated for the sake of understanding the internal structure of the shell-type transformer.

The shell-type transformer 100 according to an embodiment of the present disclosure is a vehicle-mounted transformer. As shown in fig. 1, the shell-type transformer 100 includes a core 110 and a winding group 120. The core 110 and the winding group 120 are accommodated in a case, not shown, in a state of being immersed in insulating oil. The core 110 includes a main leg 111 and a pair of side legs 112. A pair of side legs 112 are connected to the main leg 111. The axial direction of the core 110 is the Z-axis direction.

The winding group 120 includes a primary winding group 121 and a secondary winding group 122. The primary winding groups 121 are arranged between the secondary winding groups 122. The voltage applied to the primary winding group 121 is higher than the voltage applied to the secondary winding group 122.

As shown in fig. 2, the winding group 120 includes a plurality of plate windings 130 and a plurality of insulating plates 140. The plurality of flat plate windings 130 are arranged in an axial direction (Z-axis direction) of the core 110, and are wound around the main leg 111 while passing between the main leg 111 and the side leg 112. Each of the plurality of plate windings 130 has an oblong outer shape. The short side direction of the flat winding 130 is the X-axis direction, and the long side direction of the flat winding 130 is the Y-axis direction. Each of the plurality of plate-like windings 130 includes a conductor portion that is insulated and coated.

The plurality of insulating plates 140 are arranged in an axial direction (Z-axis direction) of the core 110 and are located at positions between adjacent ones of the plurality of plate-like windings 130. The flat plate windings 130 and the insulating plates 140 are alternately arranged one by one in the axial direction (Z-axis direction) of the core 110. Further, one flat winding 130 may be disposed for a plurality of insulating plates 140. The insulating plate 140 has a substantially oval shape like the flat plate winding 130.

As shown in fig. 2 and 3, a plurality of insulators are disposed in contact with at least one of the plurality of flat windings 130. In the present embodiment, as the plurality of insulators, a plurality of insulating spacers 141, a plurality of first corner pieces 160, 170, and a plurality of second corner pieces 150 are arranged.

The plurality of insulators includes a plurality of first insulators and at least one second insulator in contact with the at least one planar winding 130 at a position closer to the core 110 than the plurality of first insulators. The at least one second insulator is composed of a material having a lower dielectric constant than the plurality of first insulators. In this embodiment, the plurality of first insulators are constituted by the pressing plate. The at least one second insulator is composed of a polyamide resin. In addition, as long as the dielectric constant of the second insulator is lower than that of the first insulator, the material of the first insulator is not limited to the platen, and the material of the second insulator is not limited to the polyamide resin.

Specifically, the plurality of insulating spacers 141 are arranged on the main surface 140s of each of the plurality of insulating plates 140 at intervals. Each of the plurality of insulating spacers 141 is bonded and fixed to the main surface 140s of the insulating plate 140. Each of the plurality of insulating spacers 141 is sandwiched between the flat plate winding 130 and the insulating plate 140, and a flow path through which insulating oil flows is formed between the flat plate winding 130 and the insulating plate 140 by the insulating spacers 141.

As shown in fig. 3, the plurality of insulating spacers 141 include a plurality of first insulating spacers 141a disposed at positions close to the main leg 111, a plurality of second insulating spacers 141b disposed at positions close to the side leg 112, and a plurality of third insulating spacers 141c other than the plurality of first insulating spacers 141a and the plurality of second insulating spacers 141b on the main surface 140s of each of the plurality of insulating plates 140.

In the present embodiment, each of the plurality of first insulating spacers 141a and the plurality of second insulating spacers 141b is a second insulator, and the plurality of third insulating spacers 141c is a first insulator. That is, the dielectric constant of the material constituting each of the plurality of first insulating spacers 141a and the plurality of second insulating spacers 141b is lower than the dielectric constant of the material constituting each of the plurality of insulating plates 140 and the plurality of third insulating spacers 141 c. At least one of the plurality of first insulating spacers 141a and the plurality of second insulating spacers 141b may be a second insulating material, and all of the remaining plurality of first insulating spacers 141a and the plurality of second insulating spacers 141b and the plurality of third insulating spacers 141c may be a first insulating material. Alternatively, when at least one of the first corner fittings 160 and 170 and the second corner fitting 150, which will be described later, is a second insulator, all of the plurality of insulating spacers 141 may be first insulators.

As shown in fig. 2 and 3, the shell transformer 100 further includes a plurality of first corner pieces 160, 170 and a plurality of second corner pieces 150. In the present embodiment, a part of the plurality of first corner fittings 160 and 170 and the plurality of second corner fittings 150 disposed at a position where a high electric field is generated is a second insulator, and the remaining corner fittings are first insulators. Specifically, in the winding group 120, the second corner piece 150 in contact with the outer side surface of the flat plate-shaped winding 130 having a relatively high electric field generated at the end or the first corner pieces 160, 170 in contact with the inner side surface of the flat plate-shaped winding 130 having a relatively high electric field generated at the end is a second insulator, and the second corner piece 150 in contact with the outer side surface of the flat plate-shaped winding 130 having a relatively low electric field generated at the end or the first corner piece 160, 170 in contact with the inner side surface of the flat plate-shaped winding 130 having a relatively low electric field generated at the end is a first insulator. In addition, when at least one of the plurality of insulating spacers 141 is a second insulator, the plurality of first corner fittings 160 and 170 and the plurality of second corner fittings 150 may be both first insulators.

The plurality of first corner pieces 160, 170 are located at positions sandwiched between the inner side faces 130a of the respective plurality of plate-like windings 130 and the main leg 111. The plurality of first corner pieces 160, 170 are configured to enclose the main leg 111. Each of the plurality of first corner pieces 160, 170 is in contact with the inner side 130a of the planar winding 130.

The plurality of first corner pieces 160 extend along the inner side surface 130a in a first direction (Y-axis direction), respectively. Each of the plurality of first corner pieces 170 includes a portion extending in a first direction (Y-axis direction) along a corner of the inner side surface 130a and a portion extending in a second direction (X-axis direction) orthogonal to the first direction (Y-axis direction).

The plurality of second corner pieces 150 are located at positions sandwiched between the outer side faces 130b and the side leg portions 112 of the respective plurality of flat plate windings 130. Each of the plurality of second corner pieces 150 extends along the side leg 112 in a first direction (Y-axis direction). Each of the plurality of second corner pieces 150 is in contact with the outer side 130b of the planar winding 130.

Here, the specific shape of each of the plurality of first corner fittings 160, 170 and the plurality of second corner fittings 150 in the present embodiment will be described. In the present embodiment, each of the first corner fittings 160 and 170 and the second corner fitting 150 is a corner fitting having a bent portion at one end portion in the axial direction (Z-axis direction) of the main portion, which will be described later, but may be a channel having bent portions at both end portions in the axial direction (Z-axis direction) of the main portion.

Each of the plurality of first corner pieces 160 includes a main portion 161 along the axial direction (Z-axis direction) of the core 110 and a bent portion 162 bent from an end of the main portion 161 in the axial direction (Z-axis direction) and in contact with the main surface 140s of the insulating plate 140. The main portion 161 extends along the inner side surface 130a and in the first direction (Y-axis direction). The bent portions 162 are formed in a comb-tooth shape. The bent portion 162 extends in the second direction (X-axis direction) from an end of the main portion 161 in the axial direction (Z-axis direction).

Each of the plurality of first corner pieces 170 includes a main portion 171 along the axial direction (Z-axis direction) of the core 110, and bent portions 172, 173 bent from the end of the main portion 171 in the axial direction (Z-axis direction) and in contact with the main surface 140s of the insulating plate 140. The main portion 171 includes a portion extending in the first direction (Y-axis direction) along the corner of the inner side surface 130a and a portion extending in the second direction (X-axis direction).

The curved portions 172 and 173 are formed in a comb-tooth shape. The curved portion 172 extends in the second direction (X-axis direction) from an end portion of the axial direction (Z-axis direction) of a portion of the main portion 171 extending in the first direction (Y-axis direction). The curved portion 173 extends in the first direction (Y-axis direction) from an end of an axial direction (Z-axis direction) of a portion of the main portion 171 extending in the second direction (X-axis direction).

Each of the plurality of second corner pieces 150 includes a main portion 151 along the axial direction (Z-axis direction) of the core 110 and a bent portion 152 bent from an end portion of the main portion 151 in the axial direction (Z-axis direction) and in contact with the main surface 140s of the insulating plate 140. The main portion 151 extends along the outer side surface 130b in the first direction (Y-axis direction). The curved portion 152 is formed in a comb-tooth shape. The bending portion 152 extends in the second direction (X-axis direction) from an end of the main portion 151 in the axial direction (Z-axis direction).

As described above, in the shell-type transformer 100 of the present embodiment, the second insulator made of the low dielectric constant material is used only in the insulating member adjacent to the portion where the high electric field is generated in the planar winding 130, that is, the end portion of the planar winding 130, so that the electric field in the oil can be relaxed to improve the insulation reliability while suppressing the increase in the device cost. Specifically, only the first insulating spacer 141a, the second insulating spacer 141b, the first corner pieces 160, 170, and the second corner piece 150 are made of a low dielectric constant material, and the insulating plate 140 and the third insulating spacer 141c are made of a pressing plate, so that it is possible to improve insulating reliability while suppressing an increase in the cost of the device. The structure may be applied to the primary winding group 121 alone or the secondary winding group 122. As described above, at least one of the second insulators may be disposed closer to the core than the first insulator. The at least one second insulator is in contact with the at least one planar winding 130 at a position closest to the core 110 among the plurality of insulators.

In the present embodiment, since only the material of the insulating member adjacent to the portion of the flat winding 130 where the high electric field is generated, that is, the end portion of the flat winding 130 is changed, it can be easily applied to an existing shell-type transformer.

In the shell-type transformer 100 of the present embodiment, the material of the first insulator is a pressing plate, and the material of the second insulator is a polyamide resin. An insulating member made of a low-cost pressure plate is used at a position where a high electric field is not applied, and an insulating member made of a polyamide resin having a low dielectric constant is disposed only at a position where a high electric field is applied, whereby the electric field in oil can be relaxed to improve insulation reliability while suppressing an increase in the cost of the device.

In the shell-type transformer 100 of the present embodiment, the plurality of first corner pieces 160, 170 include a portion extending in the first direction (Y-axis direction) and a portion extending in the second direction (X-axis direction) to surround the main leg 111. Accordingly, the insulating material having a low dielectric constant is disposed over the entire circumference of the inner peripheral portion of the planar winding 130, which is a portion where the high electric field is generated, so that the insulating reliability can be improved.

In the shell-type transformer 100 of the present embodiment, the bent portions 152, 162, 172, 173 of the first corner pieces 160, 170 and the second corner pieces 150 are formed in a comb-tooth shape. Accordingly, the insulating oil can flow into each of the bent portions 152, 162, 172, and 173 adjacent to each other, and therefore, the end portions of the flat plate-shaped winding 130 can be effectively cooled by the insulating oil.

In addition, the various aspects of the above-described embodiments of the present disclosure are illustrative and not intended to be a basis for limiting explanation. Accordingly, the technical scope of the present disclosure is defined based on the claims, not just the above-described embodiments. Further, the technical scope of the present disclosure encompasses all modifications within the meaning and scope equivalent to the claims.

Symbol description

100 Shell transformer, 110 core, 111 main leg, 112 side leg, 120 winding group, 121 primary winding group, 122 secondary winding group, 130 planar winding, 130a inner side, 130b outer side, 140 insulating plate, 140s main surface, 141 insulating spacer, 141a first insulating spacer, 141b second insulating spacer, 141c third insulating spacer, 150 second corner piece, 151, 161, 171 main portion, 152, 162, 172, 173 bent portion, 160, 170 first corner piece.

Claims (7)

1. A shell type transformer, comprising:

An iron core;

A plurality of plate-shaped windings which are arranged in an axial direction of the iron core and wound around the iron core;

A plurality of insulating plates arranged along the axial direction and positioned between adjacent ones of the plurality of planar windings, and

A plurality of insulators in contact with at least one of the plurality of planar windings,

The plurality of insulators includes:

a plurality of first insulators, and

At least one second insulator in contact with the at least one planar winding at a position closer to the core than the plurality of first insulators,

The at least one second insulator is composed of a material having a lower dielectric constant than the plurality of first insulators.

2. A shell-type transformer according to claim 1, wherein,

The at least one second insulator is in contact with the at least one planar winding at a location closest to the core of the plurality of insulators.

3. A shell-type transformer according to claim 1 or 2, wherein,

The plurality of first insulators are constituted by a pressing plate,

The at least one second insulator is composed of a polyamide resin.

4. A shell-type transformer according to any one of claims 1 to 3,

The at least one second insulation is at least one channel or corner piece in contact with the outer or inner side of the at least one planar winding.

5. A shell-type transformer according to any one of claims 1 to 3,

The at least one second insulator is at least one spacer disposed on a respective major surface of the plurality of insulating plates.

6. The shell-type transformer according to claim 4, wherein,

One of the at least one second insulation extends in a first direction along the outer side of the at least one planar winding,

The other second insulators of the at least one second insulator include a portion extending in the first direction and a portion extending in a second direction orthogonal to the first direction to surround the core.

7. The shell-type transformer according to claim 4, wherein,

The at least one second insulator comprises:

a main portion along the axial direction, and

A bending portion bent from the axial end portion of the main portion and in contact with a main surface of at least one of the plurality of insulating plates,

The bending portion is formed in a comb-tooth shape.