Dry-type transformer

Abstract

The utility model provides a dry-type transformer. The dry-type transformer comprises an upper clamping piece, a lower clamping piece located below the upper clamping piece, a plurality of coils connected between the upper clamping piece and the lower clamping piece, and insulating cylinders arranged outside the coils in a sleeving mode. The insulating cylinder comprises a first surrounding wall, a second surrounding wall arranged at one end of the first surrounding wall in the axial direction Z and a third surrounding wall arranged at the other end of the first surrounding wall in the axial direction Z, and the first surrounding wall is arranged outside the coil in a sleeving mode. The insulating cylinder is sleeved outside the coil, so that one side, close to an oil tank, of the coil can be protected, and the insulating property of the transformer is improved; and the insulating cylinder is sleeved with the coil and is not connected with the upper clamping piece and the lower clamping piece, so that the vibration working condition can be coped, and the structural strength is ensured.

Description

Technical Field

[0001] This utility model relates to the field of ultra-high voltage offshore wind power technology, and in particular to a dry-type transformer. Background Technology

[0002] Ultra-high voltage offshore wind turbine dry-type transformers require high reliability. Due to the high voltage levels and confined space within the offshore wind turbine nacelle, stringent requirements are placed on the transformer's insulation design, lightning strike resistance, and local voltage rating. Existing dry-type transformers, such as... Figure 1 As shown, the transformer includes an upper clamp 1, a lower clamp 2 located below the upper clamp 1, and multiple coils 5 connected between the upper clamp 1 and the lower clamp 2. The two ends of the coils 5 are clamped by upper pads 3 and lower pads 4, respectively, which are fixed to the clamps with bolts. The insulation measure involves installing insulating partitions 9 between the transformer phases. This insulation method has the following problems:

[0003] (i) It is impossible to provide insulation protection for the side of the high-voltage side that is close to the inner wall of the oil tank. Under ultra-high voltage working conditions, there is a potential risk of insulation protection failure.

[0004] (ii) When the insulating partition is fixed on the upper and lower clamps, there are weak points in the connection strength when the operating environment is in the presence of vibration. Utility Model Content

[0005] The purpose of this invention is to provide a dry-type transformer that improves the insulation performance of the transformer.

[0006] The technical solution of this utility model is: a dry-type transformer, including an upper clamp, a lower clamp located below the upper clamp, a plurality of coils connected between the upper clamp and the lower clamp, and an insulating cylinder fitted around the outside of each coil. The insulating cylinder includes a first enclosure wall, a second enclosure wall located at one end of the first enclosure wall along the Z-axis, and a third enclosure wall located at the other end of the first enclosure wall along the Z-axis. The first enclosure wall is fitted around the outside of the coil.

[0007] In the above scheme, by installing an insulating cylinder around the coil, the side of the coil near the oil tank can be protected, improving the insulation performance of the transformer; and the insulating cylinder is connected to the coil but not to the upper and lower clamps, which can cope with vibration conditions and ensure structural strength.

[0008] Preferably, the lower end of the upper clamping member is provided with a plurality of upper pads arranged along its length direction X, and the upper end of the lower clamping member is provided with a plurality of lower pads arranged along its length direction X. The plurality of upper pads and the plurality of lower pads are arranged in a one-to-one correspondence, and the coil is sandwiched between the upper pads and the lower pads. The second enclosure wall is provided with a first notch, and the third enclosure wall is provided with a second notch. The upper pads are placed at the first notch, and the lower pads are placed at the second notch.

[0009] Preferably, the upper pad and the lower pad are arranged in a cross shape on the surface of each coil; there are two first notches arranged horizontally opposite each other, and the multiple upper pads in the cross shape are divided into two groups, with the upper pads in one group placed at the first notch, and the upper pads in the other group forming a second enclosure.

[0010] There are two horizontally opposite second gaps, and the multiple cross-shaped lower pads are divided into two groups. The lower pads in one group are placed at the second gap, and the lower pads in the other group form a third enclosure.

[0011] Preferably, a spacer ring is provided between the plurality of upper pads and between the plurality of lower pads, and the spacer ring is positioned adjacent to the coil.

[0012] Preferably, the inner surface of the first enclosure is provided with a plurality of wind baffles, the plurality of wind baffles are arranged at intervals in the Z-axis direction, and the coil gap is placed in the wind baffles.

[0013] Preferably, the wind deflector is an annular ring formed along the inner circle of the first enclosure wall, and the wind deflector extends radially along the first enclosure wall.

[0014] Compared with related technologies, the beneficial effects of this utility model are as follows:

[0015] I. This utility model protects the side of the coil near the oil tank by installing an insulating cylinder around the coil, thereby improving the insulation performance of the transformer. Furthermore, the insulating cylinder is connected to the coil sleeve but not to the upper and lower clamps, which can withstand vibration conditions and ensure structural strength.

[0016] Second, the insulating cylinder is equipped with a second and third enclosure wall with enclosing pads, which can solve the problem of insufficient protection capacity of existing pads and improve the transformer's resistance to lightning strikes.

[0017] Third, the outer casing structure of the insulating cylinder increases the insulation distance and creepage distance, reduces the height of the yoke window, reduces the size of the transformer, and lowers the cost.

[0018] Fourth, the insulation cylinder is equipped with a baffle plate to form an air duct outside the coil, thereby achieving heat dissipation and reducing temperature rise. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of an existing dry-type transformer;

[0020] Figure 2 A schematic diagram of the structure of the dry-type transformer provided by this utility model;

[0021] Figure 3 This is a sectional view of the installation of the first enclosure wall, windbreak plate, and coil.

[0022] In the attached diagram: 1. Upper clamp; 2. Lower clamp; 3. Upper pad; 4. Lower pad; 5. Coil; 6. Insulating cylinder; 61. First enclosure; 62. Second enclosure; 63. Third enclosure; 64. First notch; 65. Second notch; 7. Spacer ring; 8. Wind baffle; 9. Insulating partition. Detailed Implementation

[0023] The present invention will be described in detail below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present invention can be combined with each other. For ease of description, the terms "upper," "lower," "left," and "right" appearing below only indicate that they correspond to the upper, lower, left, and right directions in the accompanying drawings and do not limit the structure.

[0024] like Figure 2 As shown, the dry-type transformer provided in this embodiment includes an upper clamp 1, a lower clamp 2, an upper pad 3, a lower pad 4, a coil 5, an insulating cylinder 6, a spacer ring 7, and a wind baffle 8.

[0025] The upper clamp 1 and lower clamp 2 are arranged parallel to each other vertically, with a length direction X. Multiple upper pads 3 are bolted to the lower end of the upper clamp 1, and multiple lower pads 4 are bolted to the upper end of the lower clamp 2. The coil 5 is clamped between the upper pads 3 and lower pads 4. The upper pads 3 and lower pads 4 are arranged in a cross shape on the surface of each coil 5; in this embodiment, four are provided. A spacer 7 is provided between the four upper pads 3, with its lower surface flush with the lower surface of the upper pad 3. A spacer 7 is also provided between the four lower pads 4, with its upper surface flush with the upper surface of the lower pad 4. The spacer 7 is positioned adjacent to the coil 5.

[0026] The insulating cylinder 6 is fitted onto the outside of each coil 5. The insulating cylinder 6 includes a first enclosure 61, a second enclosure 62 located at one axial Z end of the first enclosure 61, and a third enclosure 63 located at the other axial Z end of the first enclosure 61. The first enclosure 61 is fitted onto the outside of the coil 5 and is bolted to the coil 5. The second enclosure 62 and the third enclosure 63 extend to the outside of the first enclosure 61.

[0027] The second enclosure 62 is provided with a first notch 64. There are two first notches 64 arranged horizontally opposite each other. The four cross-shaped upper pads 3 are divided into two groups. Two upper pads 3 in one group (such as the first and second) are placed at the first notch 64, and two upper pads 3 in the other group (such as the third and fourth) enclose the second enclosure 62.

[0028] The third enclosure 63 is provided with a second notch 65. Two second notches 65 are horizontally opposite each other. The four cross-shaped lower pads 4 are divided into two groups. Two lower pads 4 in one group (such as the first and second) are placed at the second notch 65, and two lower pads 4 in the other group (such as the third and fourth) enclose the third enclosure 63. In this way, the insulation distance and creepage distance at the pad positions are increased by the second enclosure 62 and the third enclosure 63, enhancing the transformer's resistance to lightning strikes at ultra-high voltage levels.

[0029] The side of the second enclosure 62 forming the first notch 64 does not contact the upper pad 3; the side of the third enclosure 63 forming the second notch 65 does not contact the lower pad 4.

[0030] like Figure 3 As shown, the inner surface of the first enclosure 61 or the entire insulating cylinder 6 is provided with multiple wind baffles 8, which are spaced apart along the Z-axis. The coils 5 are positioned within the wind baffles 8. Each wind baffle 8 is annular along the inner ring of the first enclosure 61 and extends radially along the first enclosure 61. The multiple wind baffles 8 form an air duct, allowing a large amount of air to enter and cool the transformer during operation. The wind baffles 8 force air to enter from the bottom of the transformer and flow multiple times across the wall of the coils 5, improving heat dissipation. The wind baffles 8 can be integrally cast with the insulating cylinder 6.

[0031] After the insulating cylinder 6 is installed, it can significantly increase the creepage distance and improve the transformer's ability to resist lightning strikes under ultra-high voltage conditions of 35kV and above.

[0032] The insulating cylinder 6 has a simple structure, is easy to install, and can significantly reduce the length of the yoke and the distance between the coil and the tank wall, thereby reducing the overall size of the transformer. It is suitable for offshore wind turbine nacelles and confined spaces on ships. It also increases the creepage distance between the high and low coils of the transformer, improving insulation performance and resistance to lightning strikes.

[0033] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the content of this utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A dry-type transformer, comprising an upper clamp (1), a lower clamp (2) located below the upper clamp (1), and a plurality of coils (5) connected between the upper clamp (1) and the lower clamp (2), characterized in that, It also includes an insulating tube (6) fitted around each coil (5), the insulating tube (6) including a first enclosure (61), a second enclosure (62) located at one end of the first enclosure (61) along the Z axis, and a third enclosure (63) located at the other end of the first enclosure (61) along the Z axis. The first enclosure (61) is fitted around the coil (5).

2. The dry-type transformer according to claim 1, characterized in that, The lower end of the upper clamp (1) is provided with a plurality of upper pads (3) arranged along its length direction X, and the upper end of the lower clamp (2) is provided with a plurality of lower pads (4) arranged along its length direction X. The plurality of upper pads (3) and the plurality of lower pads (4) are arranged in a one-to-one correspondence. The coil (5) is sandwiched between the upper pads (3) and the lower pads (4). The second enclosure wall (62) is provided with a first notch (64), and the third enclosure wall (63) is provided with a second notch (65). The upper pads (3) are placed at the first notch (64), and the lower pads (4) are placed at the second notch (65).

3. The dry-type transformer according to claim 2, characterized in that, The upper pad (3) and lower pad (4) are arranged in a cross shape on the surface of each coil (5); there are two horizontally opposite first notches (64), and the multiple upper pads (3) in the cross shape are divided into two groups. The upper pads (3) in one group are placed at the first notch (64), and the upper pads (3) in the other group surround the second enclosure (62). The second gap (65) is horizontally opposite to two, and the multiple cross-shaped lower pads (4) are divided into two groups. The lower pads (4) in one group are placed at the second gap (65), and the lower pads (4) in the other group surround the third enclosure (63).

4. The dry-type transformer according to claim 2, characterized in that, A spacer ring (7) is provided between the multiple upper pads (3) and between the multiple lower pads (4). The spacer ring (7) is located adjacent to the coil (5).

5. The dry-type transformer according to claim 1, characterized in that, The inner surface of the first enclosure (61) is provided with a plurality of wind baffles (8), and the plurality of wind baffles (8) are arranged at intervals in the axial direction Z, and the coil (5) is placed in the wind baffles (8) with gaps.

6. The dry-type transformer according to claim 5, characterized in that, The wind deflector (8) is an annular ring formed along the inner circle of the first enclosure wall (61), and the wind deflector (8) extends radially along the first enclosure wall (61).

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