Partial-discharge-free dry-type transformer high-voltage coil structure

Abstract

The utility model discloses a high-voltage coil structure of a non-partial-discharge dry-type transformer. The high-voltage coil structure comprises a plurality of sections of layered high-voltage coil wires, a longitudinal heat dissipation air passage is arranged in the high-voltage coil of the dry-type transformer, and a plurality of sections of layered high-voltage coil wires in the coil are divided into an inner part and an outer part by the heat dissipation air passage; the sections of the inner side layer type high-voltage coil wires of the heat dissipation air channels are connected in an end-to-end bridging mode, and the sections of the outer side layer type high-voltage coil wires of the heat dissipation air channels are connected in an end-to-end bridging mode. The layered high-voltage coil wires on the inner sides of the heat dissipation air channels and the layered high-voltage coil wires on the outer sides of the heat dissipation air channels are directly connected end to end through inter-segment jumper wires obliquely crossing the heat dissipation air channels. The non-partial-discharge dry-type transformer high-voltage coil structure and the production process are simple and convenient, and the intensity distribution of the maximum electric field between the coil sections is improved by reducing the voltage between the adjacent line sections, so that the generation of partial discharge in the coil is eliminated, no partial discharge is generated in the coil, and the safety and the reliability in the transformer coil are improved.

Description

Technical Field

[0001] This utility model relates to the field of transformer structure technology, and in particular to a high-voltage coil structure for a dry-type transformer without partial discharge. Background Technology

[0002] With the continuous improvement of urban power grid power supply requirements and the advancement of transformer technology, dry-type transformers have become widely used in my country. Due to their advantages such as energy saving, safety, reliability, and good flame retardant performance, dry-type transformers are widely used in various industries.

[0003] If the insulation structure of a dry-type transformer coil is poorly designed during the design and manufacturing process, or if the electric field strength between layers or turns is too high, there may be insufficient insulation distance, sharp corners or burrs on the conductor. Under the action of high electric field strength, the charge capacity will concentrate at the sharp corners, causing discharge. If the discharge energy is large and discharge marks are left on the surface of the insulator, it will affect the life of the test transformer. If the discharge occurs on the cavitation or sharp corner electrodes, the discharge can penetrate into the interlayer and deep layers of the insulating paperboard, eventually leading to breakdown.

[0004] In this industry, dry-type transformers mainly reduce partial discharge by increasing the spacing between coil layers, sections, high and low voltage coils, and the distance to ground. At the same time, vacuum casting process is used in production to reduce the voids inside the material.

[0005] like Figure 1 As shown, the high-voltage coil mainly adopts a multi-segment, layered U-shaped cable structure. This U-shaped cable structure still has the problem of high inter-segment voltage. If the insulation distance is not large enough, the transformer still has partial discharge, which poses a hidden danger to the operation of the transformer. Utility Model Content

[0006] The purpose of this utility model is to provide a high-voltage coil structure for a dry-type transformer without partial discharge, which improves the electric field distribution of the high-voltage coil, reduces the intensity of the maximum electric field between transformer coil sections, thereby eliminating the generation of partial discharge inside the coil, improving the electrical performance of the dry-type transformer, and ensuring that the transformer can operate safely and reliably during its service life.

[0007] To solve the above-mentioned technical problems, this utility model provides a high-voltage coil structure for a partial discharge-free dry-type transformer, comprising multiple segments of layered high-voltage coil conductors;

[0008] The high-voltage coil of the dry-type transformer is provided with a longitudinal heat dissipation channel, and the heat dissipation channel divides the multi-segment layered high-voltage coil conductors inside the coil into two parts, inner and outer.

[0009] The segments of the inner layer high-voltage coil conductors in the heat dissipation duct are connected by a head-to-tail bridging method, and the segments of the outer layer high-voltage coil conductors are connected by a head-to-tail bridging method; the inner layer high-voltage coil conductors and the outer layer high-voltage coil conductors are directly connected head-to-tail by a segment bridging wire that crosses the heat dissipation duct.

[0010] Preferably, interlayer insulation is provided between the layers of the layered high-voltage coil conductor.

[0011] Preferably, the segments of the layered high-voltage coil conductor are provided with inter-segment insulation.

[0012] Preferably, the inner side of the layered high-voltage coil conductor is provided with inner coil insulation.

[0013] Preferably, the outer side of the layered high-voltage coil conductor is provided with an outer coil insulation layer.

[0014] Preferably, the layered high-voltage coil conductors have coil end insulation at both ends.

[0015] Preferably, the outer layer of high-voltage coil conductors are connected end to end to form the coil's input and output terminals.

[0016] Compared with the prior art, the beneficial effects of this utility model are:

[0017] This utility model discloses a partial discharge-free high-voltage coil structure for dry-type transformers. The manufacturing process is simple. By reducing the voltage between adjacent segments, it improves the intensity distribution of the maximum electric field between coil segments, thereby eliminating the generation of partial discharge inside the coil and achieving zero partial discharge inside the coil. This improves the safety and reliability of the transformer coil. The application of this structure can increase the voltage level of the dry-type transformer coil and provides a solution for designing and manufacturing high-voltage coils for dry-type transformers with higher voltage levels. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the high-voltage coil structure of an existing epoxy-cast dry-type transformer;

[0019] Figure 2 This is a schematic diagram of the high-voltage coil structure of the partial discharge-free dry-type transformer provided by this utility model;

[0020] In the diagram: 1. Layered high-voltage coil conductor; 2. Interlayer insulation; 3. Coil end insulation; 4. Inner coil insulation; 5. Outer coil insulation; 6. Incoming and outgoing terminals; 7. Inter-segment insulation; 8. Inter-segment jumper wire; 9. Heat dissipation duct. Detailed Implementation

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description and claims. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0022] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0023] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Example

[0024] This utility model provides a high-voltage coil structure for a partial discharge-free dry-type transformer. Please refer to [link / reference]. Figure 2 The transformer includes multiple segments of layered high-voltage coil conductors 1; a longitudinal heat dissipation channel 9 is provided inside the high-voltage coil of the dry-type transformer, and the heat dissipation channel 9 divides the multiple segments of layered high-voltage coil conductors 1 into inner and outer parts; the segments of the layered high-voltage coil conductors 1 inside the heat dissipation channel 9 are connected by a head-to-tail bridging method, and the segments of the layered high-voltage coil conductors 1 outside the heat dissipation channel 9 are connected by a head-to-tail bridging method; the layered high-voltage coil conductors 1 inside the heat dissipation channel 9 and the layered high-voltage coil conductors 1 outside the heat dissipation channel 9 are directly connected head-to-tail by inter-segment bridging wires 8 that cross the heat dissipation channel 9.

[0025] Specifically, the layered high-voltage coil conductor 1 has interlayer insulation 2 between the layers; the layered high-voltage coil conductor 1 has intersegment insulation 7 between the segments; the inner side of the layered high-voltage coil conductor 1 has inner coil insulation 4; and the outer side of the layered high-voltage coil conductor 1 has outer coil insulation 5.

[0026] Furthermore, the layered high-voltage coil conductor 1 is provided with coil end insulation 3 at both ends.

[0027] Furthermore, the outer layer of high-voltage coil conductors 1 are connected end to end to form the coil's input and output terminals 6.

[0028] This partial discharge-free dry-type transformer high-voltage coil structure has a simple manufacturing process. By reducing the voltage between adjacent segments, it improves the intensity distribution of the maximum electric field between coil segments, thereby eliminating the generation of partial discharge inside the coil and achieving zero partial discharge inside the coil. This improves the safety and reliability of the transformer coil. The application of this structure can increase the voltage level of the dry-type transformer coil and provides a solution for designing and manufacturing high-voltage coils of dry-type transformers with higher voltage levels.

[0029] The above description is only a description of the preferred embodiment of the present utility model and is not intended to limit the scope of the present utility model in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A high-voltage coil structure for a partial discharge-free dry-type transformer, characterized in that, Including multi-segment layered high-voltage coil conductors (1); A longitudinal heat dissipation channel (9) is provided inside the high-voltage coil of the dry-type transformer, and the heat dissipation channel (9) divides the multi-segment layered high-voltage coil conductor (1) inside the coil into two parts, inner and outer. The segments of the inner layer high-voltage coil conductor (1) of the heat dissipation duct (9) are connected by a head-to-tail bridging method, and the segments of the outer layer high-voltage coil conductor (1) are connected by a head-to-tail bridging method; the inner layer high-voltage coil conductor (1) and the outer layer high-voltage coil conductor (1) of the heat dissipation duct (9) are directly connected head-to-tail by a segment bridging wire (8) that crosses the heat dissipation duct (9).

2. The high-voltage coil structure of a partial discharge-free dry-type transformer as described in claim 1, characterized in that, The layered high-voltage coil conductor (1) has interlayer insulation (2) between the layers.

3. The high-voltage coil structure of a partial discharge-free dry-type transformer as described in claim 2, characterized in that, Inter-segment insulation (7) is provided between the segments of the layered high-voltage coil conductor (1).

4. The high-voltage coil structure of a partial discharge-free dry-type transformer as described in claim 1, characterized in that, The inner side of the layered high-voltage coil conductor (1) is provided with inner coil insulation (4).

5. The high-voltage coil structure of a partial discharge-free dry-type transformer as described in claim 1, characterized in that, The outer side of the layered high-voltage coil conductor (1) is provided with coil outer layer insulation (5).

6. The high-voltage coil structure of a partial discharge-free dry-type transformer as described in claim 1, characterized in that, The layered high-voltage coil conductor (1) has coil end insulation (3) at both ends.

7. The high-voltage coil structure of a partial discharge-free dry-type transformer as described in claim 1, characterized in that, The outer layer of high-voltage coil conductors (1) are connected end to end to form the coil's inlet and outlet terminals (6).

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