JP3331113B2 - Dry transformer winding, method of manufacturing the same, and dry transformer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire for a dry transformer winding, and more particularly to an improvement of a dry transformer winding using the wire, a method of manufacturing the same, and a dry transformer using the winding. Things.

[0002]

2. Description of the Related Art In order to improve insulation, moisture resistance and dust resistance, a dry transformer winding is impregnated with a resin so that the windings are impregnated with a resin in order to insulate the wires and to insulate the winding surface. I needed to. Conventional dry-type transformer winding
This will be described with reference to JP-A-620-620. The coil conductor according to the above described technique has a structure as shown in FIG. FIG.
1 is a schematic explanatory view of a conventional dry-type transformer winding. As shown in the figure, an insulated wire made of a conductor 1 having a wire insulation 2 provided on an outer peripheral surface is formed, and an outer layer insulation bonded to at least one side of the insulated wire along the length direction of the conductor 1. 4 and an interlayer insulating paper 5 to form a laminated winding, and a method of impregnating the laminated winding with a resin is adopted.

[0003]

In the process of manufacturing a dry-type transformer winding according to the prior art, time and labor are required for an operation of inserting an interlayer insulating paper and an operation of impregnating a resin, and there is a problem in productivity. Was. The purpose of the present invention is to solve the problems in the prior art.First, the workability in manufacturing a dry transformer is improved, and a dry transformer winding excellent in productivity is improved. Second, a method for manufacturing a dry transformer winding that easily and reliably has a different insulation thickness according to the direction,
Thirdly, it is an object of the present invention to provide a dry transformer using a winding that does not generate a defective portion based on a defective portion of the interlayer paper.

[0004]

To achieve the above object,
In the configuration of the dry transformer winding according to the first invention, the first insulating paper is wrapped in a U-shape with respect to the conductor cross section, and the second insulating paper is inverted from the top with respect to the conductor cross section. Covering the conductor and the first insulating paper from the opposite side of the first insulating paper in a shape to form a wire, forming a winding of the wire in a cylindrical coil shape, The coating is made thicker in the laminating direction than in the width direction of the winding. The dry transformer winding according to the preceding paragraph, wherein the coating is formed of a prepreg insulating material. In any one of the dry transformer windings according to the preceding paragraph, a third insulating material is interposed on the inside of the coating to adjust the thickness of the coating in the width direction and the laminating direction of the winding. It is characterized by the following. In any of the dry transformer windings according to the preceding paragraph, when the conductor is disposed at a diagonal position, an insulating material is reinforced at a corner of the conductor. .

In order to achieve the above object, a method of manufacturing a dry-type transformer winding according to a second aspect of the present invention is to supply a bare conductor, and to provide a first insulating paper from a side of the supplied conductor; Supplying a second insulating paper, the conductor and the first insulating paper,
According to the feeding direction of the second insulating paper, the first insulating paper along the conductor in a U-shape, and then the first insulating paper along the conductor in a U-shape on the conductor, Covering the second insulating paper along the inverted U-shape from the opposite side of the U-shaped body of the first insulating paper to form a wire, winding the wire, and forming a winding. It is characterized by the following.

In order to achieve the above object, a dry transformer according to a third aspect of the present invention is a dry transformer in which an insulated wire is wound around a cylindrical coil and a plurality of windings are laminated and formed.
A dry transformer, wherein the dry transformer winding according to any one of claims 1 to 4 is used for the winding.

[0007]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIG. [Embodiment 1] FIG. 1 is a sectional view of a wire used for a dry-type transformer winding according to an embodiment of the present invention. As shown in the drawing, continuous paper is used for the first insulating paper 2a, the three sides of the rectangular conductor 1 are enclosed in a U-shape, and further, continuous paper is used for the second insulating paper 2b from above. The opposite three sides of the first insulating paper 2a are enclosed in a U-shape. By winding the first and second insulating papers around the conductor in such a manner as to enclose them, the thickness of the insulating paper coating varies in the direction of the conductor 1. If the longitudinal direction of the illustrated conductor is the x direction and the short direction is the y direction, the coating thickness differs in the x direction and the y direction. That is, the ratio α of the insulating coating thickness in the x direction and the y direction
₁ : α ₂ = 1: 2. When forming such a wire in a winding machine, the lowermost layer begins to be wound from one end, is wound at the other end, is stepped up and stacked, and the next layer is similarly formed. I do. This procedure is repeated until the outermost layer is formed. Therefore, the width direction of the winding from the one end to the other end is the width direction of the winding, and the stacking direction of the step is the layer direction. Assuming that the coil width direction is the x direction and the coil laminating direction is the y direction, the insulating coating thickness in the y direction is larger than the insulating coating thickness in the x direction, and the above α ₁ : α ₂ = 1: 2,
It is not necessary to insert complicated interlayer paper, which requires complicated work, and the insulation between the layers can be provided only by the conductor coating.

FIG. 2 is a sectional view of a main part of a winding formed by winding the element wire of FIG. In FIG. 2, insulating paper used for the conductor coating is made of polyamide (PA), polyethylene naphthalate (PEN), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyethylene terephthalate (PE).
T), an insulating material having a low dielectric constant such as a prepreg insulating material may be used.

In FIG. 2, when the potential difference due to the transformer electromotive force in the illustrated portion becomes ΔV1 and ΔV2, the insulation coating thickness α _{1 in} the coil width direction and the insulation coating thickness α _{2 in the} coil lamination direction Is the shared potential △ V1,
It preferably corresponds to the ratio of ΔV2. In FIG. 1 of [Embodiment 1], α ₁ : α ₂ = 1: 2, and the thickness of the insulating paper can be increased more than necessary particularly in the coil width direction.

[Embodiment 2] Another embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a cross-sectional view of a wire used for a dry transformer winding according to another embodiment of the present invention, and FIG. 4 is a wire used for a dry transformer winding according to still another embodiment of the present invention. It is sectional drawing. FIG. 3 shows a wire in which the insulating paper 2C (thickness β) is included on one side of the conductor 1 in the coil laminating direction. FIG. 4 shows the insulating paper 2C (thickness β
/ 2) are arranged on both sides of the conductor. If such wires are used, insulating papers 2a having different thicknesses (thickness γ)
And 2b (thickness [gamma]) and insulating paper 2C (thickness [beta] or [beta] / 2), the ratio of the shared potential difference in the laminating direction and the width direction can be any value.
By winding these strands shown in FIGS. 3 and 4 by a winding machine, a dry transformer winding can be formed.

[Embodiment 3] Still another embodiment of the present invention will be described with reference to FIG. [Embodiment
In section A shown in FIG. 2 of [1], since the conductors 1a and 1b are arranged between the layers and diagonally, the thickness of the insulating paper on the diagonal line between the lines may be reduced. FIG. 5 is a cross-sectional view of a wire used for a dry-type transformer winding according to still another embodiment of the present invention. In FIG. 5, continuous insulating paper 2a and insulating paper 2b are extended and wound around the corners of the conductor 1,
By ensuring the inclusion, the thickness of the insulating paper on the diagonal line between the wires is ensured, and the insulation performance of the strand can be improved.
By using this element wire and winding it by a winding machine, a winding can be made.

Embodiment 4 Still another embodiment of the present invention will be described with reference to FIG. FIG. 6 is a strand cross-sectional view of a dry-type transformer winding according to still another embodiment of the present invention. FIG. 6 shows a case where the element wire is wound edgewise. The short side of the wire 1 is double wrapped with a continuous insulating paper 2a and a continuous insulating paper 2b. In this manner, the insulation performance of the strand can be improved, and a winding using the strand can be formed.

[Embodiment 5] Still another embodiment of the present invention will be described with reference to FIG. FIG. 7 is a schematic explanatory view of a method for manufacturing a dry transformer winding according to still another embodiment of the present invention. As shown in the figure, the method includes a conductor supplying step 6, a covering attaching step 7, and a winding step 8. In the conductor supply step 6, the conductor 1 is supplied in a bare state with a copper or aluminum wire. In the coating attaching step 7, the side of an insulating sheet 2a of the supplied conductor 1, 2b sequentially, to extend along the U-shape, each coated mounting jig j _1, j _2, placed on both sides of the conductor 1 Have been. These jigs j ₁ and j ₂ are used to make the insulating papers 2 a and 2 b drawn from the rolled paper body follow the conductor 1,
According to the feeding directions of a and 2b, for example, one is formed as an opening, and the other is formed in a U-shape, and the cross-sectional area thereof is gradually reduced. This jig
₁ causes the insulating paper 2a to extend along the U-shape from the side surface of the conductor 1. Then, the jig j _2, on the insulating paper 2a which this along a U-shaped conductor 1, insulating coating from the opposite side in the U-shape and along the insulating paper 2b reversed U-shape Is formed. Next, in a winding step 8, it is wound on a roll body 8. If the roll body 8 is a coil winding machine, coil winding can be performed as it is.

Embodiment 6 Still another embodiment of the present invention will be described with reference to FIG. FIG. 8 is a schematic diagram illustrating a dry-type transformer winding according to still another embodiment of the present invention. FIG. 8 is a diagram showing a fixing method using a prepreg material having self-fusing properties, particularly as a conductor coating, in a dry transformer winding. The prepreg material is a material obtained by impregnating a resin into a fiber reinforced material, and is an uncured or semi-cured material.Using this property, the uncured resin that adheres to the material flows out when heated, and voids between the prepreg materials are formed. It is buried and fixed, but by applying pressure from the outside, the gap between the prepregs is further narrowed, and the prepreg is more firmly bonded.

In general, when a rectangular coil is wound, a force acts in a radial direction on a corner portion of the coil, that is, a bent portion,
An external force is generated, and the prepreg has good adhesiveness, but it cannot be expected that the straight portion is fixed by the external force. Then, as shown in FIG. 8, after winding the coil, the winding coil 9 is wound around a tube 10 having a contractile property filled with a liquid on the outermost periphery and heated, thereby hardening the prepreg material and causing the tube 10 to harden. The pressure on the winding coil 9 due to the expansion of the filled liquid can improve the adhesiveness of the prepreg material. In this manner, a dry transformer winding with improved prepreg material adhesion can be formed.

Embodiment 7 Still another embodiment of the present invention will be described with reference to FIG. FIG. 9 is a schematic explanatory view of a dry-type transformer according to still another embodiment of the present invention. FIG. 9 is an external view of a transformer with tap switching using windings according to an embodiment of the present invention. As shown in the figure, the transformer T with tap change has the winding coils 9 mounted on the gantry 12 in accordance with the number of phases (three phases in the figure), the transformer 13 with tap change is mounted on this, and tightened with the tightening gantry 14. ing. A terminal 15 is attached to the fastening base 14. The winding coil 9 includes:
The stripping portion 11 is formed in the circumferential direction of the winding coil 9 because the work of casting resin such as resin after winding is omitted and the winding is fixed by self-fusion. It is. In this way, a dry-type transformer having no defective interlayer can be obtained.

As described above, the present invention provides an insulating layer corresponding to an interlayer insulating paper by providing an insulating coating on a conductor and forming a part of the coating with a prepreg insulating material. The wires can be fixed to each other and the surface of the winding can be fixed only by the heat treatment after the winding of the insulated conductor. As a result, the present invention is characterized in that an inexpensive coil can be manufactured by eliminating the interlayer insulating paper of the laminated winding and reducing the material cost and energy cost by eliminating the resin casting work after the winding.

[0018]

As described above, according to the structure of the dry-type transformer winding according to the present invention, the work for inserting the interlayer insulating paper and the work for impregnating the resin can be omitted, and the productivity can be improved and the energy can be improved. And the amount of material used can be reduced. Also, by using a prepreg insulating material,
Since the wires are fixed to each other and the surface of the winding by heat treatment, it is possible to provide a dry-type transformer winding and a dry-type transformer excellent in insulation and moisture resistance.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a wire used for a dry-type transformer winding according to an embodiment of the present invention.

FIG. 2 is a sectional view of a main part of a winding formed by winding the element wire of FIG. 1;

FIG. 3 is a cross-sectional view of a wire used for a dry-type transformer winding according to another embodiment of the present invention.

FIG. 4 is a cross-sectional view of a wire used in a dry transformer winding according to still another embodiment of the present invention.

FIG. 5 is a cross-sectional view of a wire used for a dry-type transformer winding according to still another embodiment of the present invention.

FIG. 6 is a cross-sectional view of a strand used in a dry-type transformer winding according to still another embodiment of the present invention.

FIG. 7 is a schematic explanatory view of a method for manufacturing a dry-type transformer winding according to still another embodiment of the present invention.

FIG. 8 is a schematic explanatory view of a dry-type transformer winding according to still another embodiment of the present invention.

FIG. 9 is a schematic explanatory view of a dry-type transformer according to still another embodiment of the present invention.

FIG. 10 is a schematic explanatory view of a conventional dry-type transformer winding.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Conductor, 2 ... wire insulation coating, 2a ... U-shaped wire insulation coating (inside), 2b ... U-shaped wire insulation coating, 2c ... wire insulation reinforcement coating, 3 ... winding inner circumference insulation layer 4, a winding outer peripheral insulating layer, 5: interlayer insulating paper, 6: conductor supply section, 7: coating attaching section, 8: conductor winding section, 9: winding coil, 10: tube, 11: coil stripe section

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Yuki Taneda 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa, Japan Examiner, Hitachi, Ltd. Production Engineering Research Laboratory Naohiro Shigeta (58) Fields surveyed (Int.Cl. ⁷ , (DB name) H01F 27/28 H01F 27/32 H01F 30/00 H01B 7/00

Claims (6)

(57) [Claims] 1. A first insulating paper is wrapped in a U-shape with respect to a conductor cross section, and a second insulating paper is placed on the opposite side of the first insulating paper in an inverted U-shape with respect to the conductor cross section. To form a wire by covering the conductor and the first insulating paper so as to wrap the wire, and form a winding in which the wire is wound into a cylindrical coil shape, and the coating is laminated from the width direction of the winding. Dry transformer winding characterized in that the direction is thickened. 2. The dry transformer winding according to claim 1, wherein the coating is formed of a prepreg insulating material. 3. The dry-type transformer winding according to claim 1, wherein a third insulating material is provided inside the coating to cover the coating in the width direction and the stacking direction of the winding. Dry transformer winding characterized in that the thickness is adjusted. 4. The dry transformer winding according to claim 1, wherein when the conductor is disposed at a diagonal position, an insulating material is reinforced at a corner of the conductor. Dry transformer winding characterized by doing so. 5. A bare wire conductor is supplied, a first insulating paper and a second insulating paper are supplied from the side of the supplied conductor, and the conductor and the first insulating paper and the second insulating paper are supplied. According to the paper feeding direction, the first insulating paper is made to conform to the conductor in a U shape, and then the second insulating paper is placed on the conductor in which the first insulating paper is made to conform to the U shape. Dry type transformer characterized by forming a wire by covering along the inverted U-shape from the opposite side of the U-shaped body of the first insulating paper, winding the wire and forming a winding. Method of manufacturing the winding. 6. A dry transformer in which an insulated wire is wound around a cylindrical coil and a winding is laminated and formed in a plurality of stages, wherein the winding is wound on the winding. Dry type transformer characterized by using wires.