Double splitter body structure of high plant transformer for power plant

Abstract

The utility model discloses a double splitter body structure of a high plant transformer for a power plant, which comprises two groups of low-voltage windings, the first low-voltage winding is positioned at the upper part of the splitter body, the second low-voltage winding is positioned at the lower part of the splitter body, and the first low-voltage winding and the second low-voltage winding are wound by adopting a double-layer double-helix structure; high-voltage windings are respectively wound outside the first low-voltage winding and the second low-voltage winding; voltage regulating coils are respectively wound outside the two groups of high-voltage windings; and the voltage regulating coils and the high-voltage windings adopt a continuous winding structure. A first low-voltage winding and a second low-voltage winding of the double-splitter body structure of the high-voltage transformer for the power plant are wound by adopting a double-layer double-helix structure of a self-adhesive transposed conductor and are jointly wound on the same inner paper tube. And the two groups of low-voltage windings are wound on the same inner paper tube together, so that separate sleeving and press fitting processes are reduced, and the production efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of high-voltage plant-used working transformers, in particular to a double-split body structure of a high-voltage plant transformer used in a power plant. Background Art

[0002] The power plant power system is equipped with two 6kV working sections A and B, and each generator set is equipped with a 45 / 28-28MVA high-voltage plant working transformer. The low-voltage side of the high-voltage plant working transformer adopts double-split windings. The high-voltage side power supply is connected from the generator outlet through the phase-isolated closed busbar, and the two independent low-voltage sides are respectively connected to the plant 6kV working sections A and B through the 6kV common box closed busbar. The neutral point of the low-voltage side of the high-voltage plant working transformer is connected to the neutral point resistor cabinet on the low-voltage side through a cable. The high-voltage plant working transformer is used to reduce the generator terminal voltage of 18kV to 6kV to supply power to the plant load of the power plant. For details of the system wiring method, please see the attached Figure 1 .

[0003] The double-split transformer structure of the high-voltage transformer usually adopts two schemes. Scheme 1 is radial splitting: from the core to the outside, it is low-voltage winding 1-high-voltage winding-low-voltage winding 2; Scheme 2 is axial splitting: from the core to the outside, it is low-voltage winding 1 and low-voltage winding 2 arranged axially up and down, and the outside is high-voltage winding; the advantages of scheme 1 are simple production and strong resistance to sudden short circuits, but the two half-through impedance matching is difficult, the output voltage deviation on the low-voltage side is large, and the overall cost is too high, and the cost performance is poor. The advantages of scheme 2 are simple impedance matching and small output voltage deviation on the low-voltage side, but the axially split low-voltage winding is difficult to lead out and has poor resistance to sudden short circuits. The axially split low-voltage winding of scheme 2 usually adopts a single spiral or double spiral structure with multiple flat copper wires wound in parallel, and the middle head is led out by welding copper foil. The production process is very complicated, the quality is difficult to guarantee, and the performance is poor. Utility Model Content

[0004] The utility model aims to provide a double-split transformer body structure for a power plant transformer, which not only overcomes the disadvantages of the difficulty in leading out the low-voltage axial split, but also overcomes the disadvantages of the poor ability to resist sudden short circuits of ordinary flat wires, and also overcomes the disadvantages of the low cost performance of radial split.

[0005] In order to solve the above technical problems, the utility model provides a double split body structure of a high-voltage transformer for a power plant, comprising two sets of low-voltage windings, wherein the first low-voltage winding is located at the upper part of the split body, and the second low-voltage winding is located at the lower part of the split body, and the first low-voltage winding and the second low-voltage winding are both wound in a double-layer double-helix structure;

[0006] High voltage windings are respectively wound outside the first low voltage winding and the second low voltage winding;

[0007] Voltage regulating coils are respectively wound outside the two groups of high-voltage windings, and the voltage regulating coils and the high-voltage windings adopt a continuous winding structure.

[0008] Preferably, the first low-voltage winding and the second low-voltage winding are both wound in a double-layer double-helix structure of self-adhesive transposed conductors, and are wound together on the same inner paper cylinder.

[0009] Preferably, the first low-voltage winding is located at the upper part of the inner paper tube, and is wound from the top of the inner paper tube to the middle in a left-winding manner, and then wound from the middle to the top in a right-winding manner, so that the first low-voltage winding forms a double-layer double-helix structure at the upper part of the inner paper tube, so that the lead-out point of the first low-voltage winding is located at the top of the inner paper tube.

[0010] Preferably, the second low-voltage winding is located at the lower part of the inner paper tube, and is wound from the bottom end of the inner paper tube to the middle in a left-winding manner, and then wound from the middle to the bottom in a right-winding manner, so that the second low-voltage winding forms a double-layer double-helix structure at the lower part of the inner paper tube, so that the lead-out point of the second low-voltage winding is located at the bottom end of the inner paper tube.

[0011] Preferably, the two groups of high-voltage windings are respectively wound from the middle to both ends, so that the lead-out points of the two groups of high-voltage windings are respectively located at the top and bottom ends of the inner paper tube.

[0012] Preferably, the voltage regulating coil adopts a layered structure with upper and lower parts connected in parallel.

[0013] Compared with the prior art, the beneficial effects of the utility model are:

[0014] 1. The first low-voltage winding and the second low-voltage winding of the double-split transformer structure of the power plant transformer are both wound with a double-layer double-helix structure of self-adhesive transposed conductors, and are wound together on the same inner paper cylinder. The two sets of low-voltage windings are wound together on an inner paper cylinder, which reduces the separate set and press-fitting process and improves production efficiency;

[0015] 2. Since the high-voltage winding has a central incoming line structure and has many radial outlets in the middle, in order to avoid the difficulty in installing the voltage regulating coil, the utility model adopts a voltage regulating coil and a high-voltage coil connected winding structure. The voltage regulating coil adopts a layered upper and lower part parallel structure. The upper and lower parts of the voltage regulating coil are connected in parallel to reduce the ampere-turn imbalance and improve the ability to resist sudden short circuits. It is also convenient for the middle tap of the high-voltage coil to be led out from the middle area of ​​the voltage regulating coil, which perfectly solves the production problem, simplifies the installation process, and greatly improves production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a wiring diagram of the power plant's electrical system;

[0017] Figure 2This is a schematic diagram of the double-split body structure of a high-voltage transformer for a power plant provided by the utility model;

[0018] Figure 3 It is a structural schematic diagram of the low-voltage coil provided by the utility model;

[0019] Figure 4 It is a schematic diagram of the winding of the double-layer double-helix structure of the low-voltage winding provided by the utility model;

[0020] Figure 5 It is a structural schematic diagram of a high-voltage coil provided by the utility model.

[0021] In the figure: 1. First low-voltage winding; 2. Second low-voltage winding; 3. High-voltage winding; 4. Voltage regulating coil. DETAILED DESCRIPTION

[0022] The following is a further detailed description of the present invention in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description and claims. It should be noted that the 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.

[0023] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0024] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "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 be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances. Example

[0025] The utility model provides a double split body structure of a high-voltage transformer for a power plant, please refer to Figure 2-5 , including two groups of low-voltage windings, wherein the first low-voltage winding 1 is located at the upper part of the splitter body, and the second low-voltage winding 2 is located at the lower part of the splitter body, and the first low-voltage winding 1 and the second low-voltage winding 2 are both wound in a double-layer double-helix structure; high-voltage windings 3 are respectively wound outside the first low-voltage winding 1 and the second low-voltage winding 2; voltage-regulating coils 4 are respectively wound outside the two groups of high-voltage windings 3, and the voltage-regulating coils 4 and the high-voltage windings 3 adopt a continuous winding structure.

[0026] Specifically, the first low-voltage winding 1 and the second low-voltage winding 2 are both wound in a double-layer double-helix structure of self-adhesive transposed conductors and are wound together on the same inner paper cylinder. The two sets of low-voltage windings are wound together on one inner paper cylinder, which reduces the separate set and press-fitting processes and improves production efficiency.

[0027] Furthermore, the first low-voltage winding 1 is located at the upper part of the inner paper tube, and is wound from the top end of the inner paper tube to the middle in a left-winding manner, and then is wound from the middle toward the top in a right-winding manner, so that the first low-voltage winding 1 forms a double-layer double-helix structure at the upper part of the inner paper tube, so that the lead-out point of the first low-voltage winding 1 is located at the top end of the inner paper tube; the second low-voltage winding 2 is located at the lower part of the inner paper tube, and is wound from the bottom end of the inner paper tube to the middle in a left-winding manner, and then is wound from the middle toward the bottom in a right-winding manner, so that the second low-voltage winding 2 forms a double-layer double-helix structure at the lower part of the inner paper tube, so that the lead-out point of the second low-voltage winding 2 is located at the bottom end of the inner paper tube.

[0028] Specifically, the two groups of high-voltage windings 3 are respectively wound from the middle to both ends, so that the lead-out points of the two groups of high-voltage windings 3 are respectively located at the top and bottom of the inner paper tube.

[0029] Specifically, the voltage regulating coil 4 adopts a layered upper and lower parallel structure. Since the high-voltage winding 3 is a central incoming line structure with more radial outlets in the middle, in order to avoid the difficulty of installing the voltage regulating coil 4, the utility model adopts a voltage regulating coil 4 and a high-voltage coil 3 winding structure, and the voltage regulating coil 4 adopts a layered upper and lower parallel structure. The upper and lower parts of the voltage regulating coil 4 are connected in parallel to reduce the ampere-turn imbalance and improve the ability to resist sudden short circuits, and it is also convenient for the middle tap of the high-voltage coil 3 to be led out from the middle area of ​​the voltage regulating coil 4, which perfectly solves the production problem, simplifies the installation process, and greatly improves production efficiency.

[0030] The above description is only a description of the preferred embodiment of the utility model, and is not any limitation on the scope of the utility model. Any changes and modifications made by ordinary technicians in the field of the utility model based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. A double-split transformer structure for a power plant, characterized in that: It comprises two groups of low-voltage windings, wherein the first low-voltage winding (1) is located at the upper part of the splitter body, and the second low-voltage winding (2) is located at the lower part of the splitter body, and the first low-voltage winding (1) and the second low-voltage winding (2) are both wound in a double-layer double-helix structure; High-voltage windings (3) are respectively wound outside the first low-voltage winding (1) and the second low-voltage winding (2); Voltage regulating coils (4) are respectively wound outside the two groups of high-voltage windings (3), and the voltage regulating coils (4) and the high-voltage windings (3) adopt a continuous winding structure.

2. A double-split transformer body structure for a power plant as claimed in claim 1, characterized in that: The first low-voltage winding (1) and the second low-voltage winding (2) are both wound using a double-layer double-helix structure of self-adhesive transposed conductors and are wound together on the same inner paper cylinder.

3. A double-split transformer body structure for a power plant as claimed in claim 2, characterized in that: The first low-voltage winding (1) is located at the upper part of the inner paper tube, and is wound from the top of the inner paper tube to the middle in a left-hand winding manner, and then is wound from the middle to the top in a right-hand winding manner, so that the first low-voltage winding (1) forms a double-layer double-helix structure at the upper part of the inner paper tube, so that the lead-out point of the first low-voltage winding (1) is located at the top of the inner paper tube.

4. A double-split transformer body structure for a power plant as claimed in claim 2, characterized in that: The second low-voltage winding (2) is located at the bottom of the inner paper tube, and is wound from the bottom end of the inner paper tube to the middle in a left-hand winding manner, and then is wound from the middle to the bottom in a right-hand winding manner, so that the second low-voltage winding (2) forms a double-layer double-helix structure at the bottom of the inner paper tube, so that the lead-out point of the second low-voltage winding (2) is located at the bottom end of the inner paper tube.

5. The double-split transformer structure for a power plant as claimed in claim 2, characterized in that: The two groups of high-voltage windings (3) are respectively wound from the middle to both ends, so that the lead-out points of the two groups of high-voltage windings (3) are respectively located at the top end and the bottom end of the inner paper tube.

6. A double-split transformer body structure for a power plant as claimed in claim 5, characterized in that: The voltage regulating coil (4) adopts a layered structure with upper and lower parts connected in parallel.

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