Silicone rubber dry-type transformer coil

Abstract

The utility model provides a dry-type transformer coil using silicone rubber as coil external insulation, which comprises a coil formed by combining a plurality of layered wires and insulating materials for isolating the interlayer wires, and is of an integrated structure formed by pouring and curing the coil through liquid silicone rubber and then pouring and curing the coil through epoxy resin. The insulation system has better elasticity and tensile strength and can adapt to the change of mechanical internal stress when the load fluctuates frequently, and the mechanical strength and the electrical performance of the coil are not affected.

Description

Technical Field

[0001] The utility model relates to the field of transformers, in particular to a silicone rubber dry-type transformer coil. Background Art

[0002] At present, the dry-type power transformer wire wrap mainly uses epoxy resin as the external insulation of the winding.

[0003] The epoxy resin currently used in this technology is very rigid. Therefore, it is easy to crack when combined with the copper wire in the transformer winding, which is not conducive to application under conditions of frequent load changes or frequent changes in external ambient temperature. In addition, the temperature resistance grade of the epoxy resin material currently used in dry-type transformers is usually F or H, and the cost of H-grade epoxy resin is very high. Therefore, new materials are needed to improve the temperature resistance grade of the dry-type transformer winding insulation system.

[0004] In addition, for dry-type transformer coils encapsulated with ordinary silicone rubber, due to the lack of rigidity of the silicone rubber material, a fiberglass inner tube needs to be added to provide support for the coil; the easy cracking of the fiberglass tube reduces the overall performance of the transformer coil. Utility Model Content

[0005] The problem to be solved by the utility model is that the use of silicone rubber as the outer insulating material of the coil can improve the temperature resistance of the wire insulation system, which can generally reach above R level; at the same time, it can solve the problem of cracking of the outer insulation of the coil caused by changes in mechanical internal stress due to frequent load fluctuations; the coil is then cast as a whole with epoxy resin to solve the problem that the silicone rubber material is not rigid enough to support the coil.

[0006] In order to solve the above technical problems, the utility model proposes a silicone rubber dry-type transformer coil package, comprising a multi-layer coil conductor, wherein adjacent layers of the coil conductor are isolated by insulating paper;

[0007] The interlayer gaps of the coil conductor are filled with the silicone rubber, so that the insulating paper is fully impregnated with liquid silicone rubber, thereby ensuring that the coil conductor is completely covered by the silicone rubber; the surface of the wire package body protected by the silicone rubber is then integrally poured with epoxy resin and cured into shape.

[0008] Furthermore, the coil conductor is an annular structure, and the cross-sectional area of ​​the coil is circular, elliptical or rectangular.

[0009] Furthermore, insulating paper refers to a flat solid insulating material, including insulating paper, non-woven fabric, NOMAX paper or DMD, etc.

[0010] The beneficial effects of the utility model are:

[0011] The utility model adopts silicone rubber to replace epoxy resin as the outer insulation of the transformer coil, thereby improving the temperature resistance of the coil insulation system, generally reaching R level or above.

[0012] Silicone rubber material has good elasticity and tensile strength, and will not crack or be damaged due to the mechanical internal stress generated by frequent fluctuations in transformer load.

[0013] The epoxy resin outer encapsulation layer has good mechanical strength and provides support for the silicone rubber covered coil.

[0014] The wire wrapped copper or aluminum is not directly encapsulated by epoxy resin, which is easier to recycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a cross-sectional view of the first embodiment of the utility model;

[0016] Figure 2 It is a top view of the first embodiment of the utility model. DETAILED DESCRIPTION

[0017] The following is a more detailed description of the silicone rubber dry-type transformer coil of the utility model in conjunction with the schematic diagram, which shows the preferred embodiment of the utility model. It should be understood that those skilled in the art can modify the utility model described herein and still achieve the beneficial effects of the utility model. Therefore, the following description should be understood as being widely known to those skilled in the art, and not as a limitation to the utility model.

[0018] In the description of the present invention, it should be noted that directional words, such as the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating directions and positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of narrating the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and cannot be understood as limiting the specific protection scope of the present invention.

[0019] In the present invention, unless otherwise specified and limited, the terms "assembly", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can also be a mechanical connection; it can be directly connected, or it can be connected through an intermediate medium, or the two elements can be internally connected. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0020] The present invention is described in more detail in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the accompanying drawings are in very simplified form and in non-precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.

[0021] like Figure 1 to Figure 2 As shown, the utility model proposes a silicone rubber dry-type transformer coil, comprising a coil conductor 1, a silicone rubber material 3, an interlayer insulating paper 4 and an epoxy resin 2; the conductor 1 coated with insulation is continuously wound along the axial direction to form a plurality of independent single-layer conductor cylinders, and each layer of conductor is isolated by the insulating paper 4; the coil formed by this scheme is poured or impregnated with liquid silicone rubber, the silicone rubber fully impregnates the insulating paper 4, and completely fills the gap between the conductor 1 layers, and completely covers the conductor 1; the coil coated with silicone rubber is vacuum poured with epoxy resin and cured into a whole.

[0022] In summary, in this embodiment, the external insulation of the coil of the proposed silicone rubber dry-type transformer wire package adopts high-performance liquid silicone rubber. Since the silicone rubber has certain elasticity and tensile strength within the working temperature range of the wire package, it can adapt to the mechanical internal stress generated when the load changes frequently, thereby improving the reliability of the external insulation of the coil; the epoxy resin poured and cured on the outermost layer of the wire package plays a good supporting role for the transformer wire package.

[0023] The above are only preferred embodiments of the present invention and do not limit the present invention in any way. Any technician in the relevant technical field, without departing from the scope of the technical solution of the present invention, may make any equivalent replacement or modification to the technical solution and technical content disclosed in the present invention, which shall be deemed as the content of the technical solution of the present invention and still fall within the protection scope of the present invention.

Claims

1. A silicone rubber dry-type transformer coil, characterized in that: It comprises a multi-layer coil conductor (1), wherein adjacent layers of the coil conductor are isolated by insulating paper (4); The interlayer gaps of the coil conductor (1) are filled with silicone rubber (3); the outer layer of the coil body protected by the silicone rubber is epoxy resin (2).

2. The silicone rubber dry-type transformer coil according to claim 1, characterized in that: The coil conductor is a ring structure, and the cross-sectional area of ​​the coil is circular, elliptical or rectangular.

3. The silicone rubber dry-type transformer coil according to claim 1, characterized in that: Insulation paper (4) refers to a flat solid insulation material, including insulation paper, non-woven fabric, NOMAX paper or DMD.

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