Transformer body pressing structure and pressing operation device

Abstract

A transformer body pressing structure, comprising an upper clamping member and a lower clamping member, wherein a coil is located between the upper clamping member and the lower clamping member; an elastic pressing block is further connected between the upper clamping member and / or the lower clamping member and the coil; a pulling plate is further connected between the upper clamping member and the lower clamping member; the lower end of the pulling plate is fixedly connected to the lower clamping member, and the upper end of the pulling plate is connected to the upper clamping member by means of a locking member; and after the upper clamping member is connected to the upper end of the pulling plate by means of the locking member, Z-direction relative displacement between the pulling plate and the upper clamping member is locked. The transformer body pressing structure uses the cooperation between the pulling plate and the locking member to lock the relative vertical displacement of the upper clamping member and the lower clamping member, thereby improving the vibration resistance and short-circuit resistance of a product, and saving on operation space. Moreover, the insulation distance between an upper part and an iron yoke can be saved on, thereby effectively reducing costs. The structure is free of tip burrs of threads and nuts, which prevents the generation of metal chips that could fall into a transformer body and cause accidents of excessive partial discharge and breakdown, and eliminates the hidden danger of point discharge during lightning strikes.

Description

A transformer body compression structure and compression operating device Technical Field

[0001] The present invention relates to the field of transformer manufacturing, and in particular to a transformer body pressing structure and a pressing operating device. Background Art

[0002] Special transformers such as onshore and offshore wind turbine nacelle transformers, high-speed magnetic levitation transformers, locomotive transformers, and nuclear power Class 1E dry-type transformers require high reliability. Operating in a vibrating environment places stringent demands on vibration and short-circuit resistance. Transformer reliability is closely tied to the coil compression process. Loosening of the pressure pins can cause the coil to loosen and lead to transformer failure. Ensuring that the pressure pins on the transformer body do not loosen while maintaining a compact upper insulation space and maintaining effective compression is a key technical challenge in improving transformer reliability.

[0003] Conventional pressure-stud systems typically use a bolt-and-nut fastening structure, relying on the nut's tightening force to hold the transformer body in place. This structure is susceptible to loosening under vibration or sudden short-circuit conditions, creating potential malfunctions and making it difficult to pass vibration and sudden short-circuit tests. This structure also requires additional space between the clamp and the spacer for wrench tightening, increasing the distance between the coil and the yoke, and increasing transformer costs. Furthermore, during tightening and operation, the threads are prone to wear, generating iron chips that can enter the transformer body. Furthermore, sharp corners and burrs on the bolt threads and nuts can cause excessive partial discharge.

[0004] Through searching, it is found that there are technical documents related to transformer coil clamping devices in the prior art. For example, the publication number is "CN214123682U" and the name is "A coil clamping frame for dry-type transformers". It relates to a coil clamping frame for dry-type transformers, and relates to the technical field of dry-type transformers. It includes a base frame, on which a battery core is provided, and a transformer coil is sleeved on the battery core, and the base frame is provided with an upper fixed plate and a lower fixed plate for clamping and fixing the transformer coil; an expansion and telescopic column is provided on a side wall of the lower fixed plate in contact with the base frame, and the expansion and telescopic column includes a fixed column and a movable column sleeved on the outer wall of the fixed column, an elastic expansion body is provided in the fixed column, and an elastic member is provided on the end of the elastic expansion body close to the movable column, and the end of the elastic member away from the elastic expansion body is fixed on an inner wall of the movable column away from the fixed column.

[0005] For example, the utility model authorization announcement with publication number "CN218299572U" and titled "An Elastic Compression and Anti-Loosening Structure for Coil Spacers of Dry-Type Transformers" discloses an elastic compression and anti-loosening structure for coil spacers of dry-type transformers, comprising a clamp fixedly mounted on the iron core, a spacer disposed on the coil, and an elastic compression mechanism connecting the clamp and spacer. The elastic compression mechanism includes a bolt, a bushing, and a butterfly spring. The clamp is provided with a mounting hole, the bushing is slidably engaged with the mounting hole, the butterfly spring is sleeved on the outside of the bolt, and the bottom end of the bolt is press-fitted with the spacer.

[0006] For example, the utility model authorization announcement text with the publication number "CN205920862U" and the name "Coil clamping device for dry-type transformer and dry-type transformer thereof". It relates to a coil clamping device for dry-type transformer and dry-type transformer thereof. The coil clamping operation device includes a mounting seat, several disc spring washers, an adjustment portion and a clamping portion. The mounting seat has a clamping end, an adjustment end and a placement cavity formed between the clamping end and the adjustment end. The clamping end is used for installation close to the coil assembly, and the adjustment end is used for installation away from the coil assembly. Several disc spring washers are stacked in the placement cavity along the axial direction of the mounting seat. The adjustment portion is arranged at the adjustment end, which can move relative to the mounting seat along the axial direction of the mounting seat, and press the disc spring washer to elastically deform it. The clamping portion is arranged at the clamping end, which presses against the disc spring washer, and can press against the axial end face of the coil assembly under the action of the elastic force of the disc spring washer.

[0007] The technical solutions disclosed in the aforementioned reference documents all use bolt-fixed compression pins or compression blocks for fastening, which suffer from the aforementioned technical drawbacks. Therefore, it is necessary to develop a new transformer body compression structure and a compression operating device that can meet the transformer's requirements for vibration resistance, short-circuit resistance, and low partial discharge.

[0008] Summary of the Invention

[0009] In response to the shortcomings of the prior art, the present invention provides a transformer body compression structure, comprising an upper clamp and a lower clamp, wherein the coil is located between the upper clamp and the lower clamp, an elastic pressure block is further connected between the upper clamp and / or the lower clamp and the coil, and a pull plate is further connected between the upper clamp and the lower clamp, wherein the lower end of the pull plate is fixedly connected to the lower clamp, and the upper end of the pull plate is connected to the upper clamp by a locking member, and after the upper clamp and the upper end of the pull plate are connected by the locking member, the relative displacement in the Z direction between the pull plate and the upper clamp is locked.

[0010] Furthermore, the locking component includes a pin hole 1 provided on the upper clamp, a pin hole 2 provided on the upper end of the pull plate, and a pin shaft that can pass through the pin hole 1 and the pin hole 2.

[0011] Furthermore, the locking component includes a locking groove on the upper clamp and a locking end on the upper end of the pull plate. The locking end can be embedded in the locking groove, and the locking end and the locking groove lock the Z-direction relative displacement between the pull plate and the upper clamp through the locking surfaces that contact each other. An X-direction clamping screw is also connected between the upper clamp and the lower clamp.

[0012] Furthermore, the locking groove is a dovetail groove, and the locking end is a dovetail tenon that cooperates with the dovetail groove.

[0013] Furthermore, the locking groove is a T-shaped groove, and the locking end is a T-shaped end that matches the T-shaped groove.

[0014] Furthermore, the elastic pressing block includes an upper pressing block and a lower pressing block, the upper pressing block is located between the upper clamping piece and the top of the coil, the lower pressing block is located between the lower clamping piece and the bottom of the coil, and the upper pressing block is connected to the upper clamping piece through a buffer piece.

[0015] Furthermore, the top surface of the upper pressure block has a countersunk hole, the center of the countersunk hole is connected to a round steel column, the round steel column is sleeved on the perforated round steel, and a disc spring group sleeved on the round steel column is provided between the end surface of the perforated round steel and the bottom surface of the countersunk hole.

[0016] Furthermore, a support plate is connected between the top surface of the upper pressing block and the bottom surface of the upper clamping piece, and a parallel groove matching the outer diameter of the perforated round steel is provided on the support plate.

[0017] A transformer body pressing operation device is also proposed, which is specifically for the above-mentioned transformer body pressing structure, including an upper clamp and a lower clamp, and the upper clamp and the lower clamp are connected by a Z-direction clamping screw; the lower clamp is placed on the lower clamp, and a pressure device is connected between the upper clamp and the upper clamp, the upper end of the pressure device is connected to the upper clamp, and the lower end applies a Z-direction force to the upper clamp through a pressure plate.

[0018] Furthermore, the pressurizing device is a jack placed between the upper clamp and the upper clamping piece or a pressurizing screw connected between the upper clamp and the upper clamping piece.

[0019] Compared with the existing technology, the technical solution of the present application has the following beneficial effects: the device body clamping structure proposed in the present invention utilizes a pull plate to cooperate with a locking component to lock the relative vertical displacement of the upper and lower clamps, which greatly improves the product's vibration resistance and short-circuit resistance. At the same time, there is no need for operating space between the upper clamp and the pad, which can save the upper insulation distance and effectively reduce costs. In addition, this structure has no threaded or nut tip burrs, and no metal chips will fall into the device body during tightening and operation to cause excessive local discharge and quality accidents, and there will be no hidden dangers of tip discharge during lightning strikes. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic diagram showing the overall structure of the transformer body compression structure provided in Example 1 of the present invention and a schematic diagram showing the overall structure of the compression operation device provided in Example 4;

[0021] Figure 2 is a schematic diagram of a partial structure of a locking member provided in Example 1 of the present invention;

[0022] FIG3 is a schematic structural diagram of an upper pressure block buffer provided in accordance with the first embodiment of the present invention;

[0023] Figure 4 is a schematic structural diagram of a disc spring assembly provided in Example 1 of the present invention;

[0024] Figure 5 is a schematic diagram of the support plate structure provided in Example 1 of the present invention;

[0025] Figure 6 is a schematic diagram of the X-axis structure of the compression structure provided by the second and third embodiments of the present invention;

[0026] Figure 7 is a schematic diagram of a partial structure of a locking member provided in Example 2 of the present invention;

[0027] Figure 8 is a schematic diagram of a partial structure of a locking member provided in Example 3 of the present invention;

[0028] Figure 9: Schematic diagram of the overall structure of the compacting operation device provided in Example 4 of the present invention.

[0029] Explanation of the accompanying drawings: Upper clamp 1, X-axis clamping screw 101, Z-axis clamping screw 102, lower clamp 2, coil 3, elastic pressure block 4, upper pressure block 41, lower pressure block 42, pull plate 5, locking member 6, pin hole 1 61, pin hole 2 62, pin shaft 63, locking groove 64, dovetail groove 641, T-slot 642, locking end 65, dovetail tenon 651, T-end 652, buffer 7, countersunk hole 71, round steel column 72, disc spring group 73, disc spring sheet 730, gasket 732, perforated round steel 74, support plate 8, parallel groove 81, upper clamp 9, lower clamp 10, pressure plate 11, jack 12, pressure screw 13. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0031] Example 1: as shown in Figures 1 to 5.

[0032] A transformer body compression structure includes an upper clamp 1 and a lower clamp 2, with a coil 3 located between the upper clamp 1 and the lower clamp 2. An elastic pressure block 4 is also connected between the upper clamp 1 and / or the lower clamp 2 and the coil 3. A pull plate 5 is also connected between the upper clamp 1 and the lower clamp 2. The lower end of the pull plate 5 is fixedly connected to the lower clamp 2, and the upper end of the pull plate 5 is connected to the upper clamp 1 via a locking member 6. After the upper clamp 1 and the upper end of the pull plate 5 are connected via the locking member 6, the relative displacement in the Z direction between the pull plate 5 and the upper clamp 1 is locked.

[0033] In this embodiment, the upper clamp 1 and the lower clamp 2 are a pair of opposing I-beams, and the elastic pressure block 4 contacts the upper clamp 1 and / or the lower clamp 2 as well as the coil 3. When the upper clamp 1 and the lower clamp 2 are brought closer together in the Z direction, the elastic pressure block 4 is compressed, thereby providing a Z-direction clamping force to the coil 3. After connecting the pull plate 5 and the upper clamp 1, the locking member 6 can lock the relative displacement in the Z direction between the pull plate 5 and the upper clamp 1. Since the lower end of the pull plate 5 is fixedly connected to the lower clamp 2, the relative displacement in the Z direction between the upper clamp 1 and the lower clamp 2 is locked. Even in the face of large and high-frequency vibration conditions, the loosening will not occur, thereby improving the reliability of the transformer.

[0034] In this embodiment, the locking member 6 includes a pin hole 1 61 formed on the upper clamp 1, a pin hole 2 62 formed on the upper end of the pull plate 5, and a pin shaft 63 that can pass through pin hole 1 61 and pin hole 2 62. Before the coil 3 is compressed, pin hole 1 61 and pin hole 2 62 are not at the same height. After the coil 3 is compressed, pin hole 1 61 and pin hole 2 62 coincide with each other. At this point, the pin shaft 63 can be passed through pin hole 1 61 and pin hole 2 62 to lock the relative displacement in the Z direction between the pull plate 5 and the upper clamp 1. The locking fastening achieved by the pin shaft 63 in conjunction with pin holes 1 61 and 2 62 is different from the bolt fastening used in the prior art and will not loosen due to vibration. Furthermore, the operation process does not require space for the wrench nut, thus saving upper insulation distance. In this embodiment, there can be multiple pin holes 1 61 and 2 62 to accommodate transformer bodies with different compression displacements.

[0035] In this embodiment, the elastic pressing block 4 includes an upper pressing block 41 and a lower pressing block 42, the upper pressing block 41 is located between the upper clamp 1 and the top of the coil 3, the lower pressing block 42 is located between the lower clamp 2 and the bottom of the coil 3, and the upper pressing block 41 is connected to the upper clamp 1 through a buffer 7. The Z-direction deformation of the buffer 7 and the Z-direction displacement of the upper clamp 1 need to coincide when the pin hole 1 61 and the pin hole 2 62 are aligned. When a Z-direction force is applied to the upper clamp 1, the buffer 7 is deformed and compressed by the force. After pressing the coil 3, the buffer 7 provides an elastic buffering pressing force between the upper pressing block 41 and the coil 3. On the one hand, it can filter out some small vibrations, and on the other hand, it can avoid direct contact between the upper pressing block 41 and the coil 3, which may cause local stress damage due to excessive pressing force.

[0036] A specific embodiment of the buffer member 7 may include a countersunk hole 71 on the top surface of the upper pressure block 41. The center of the countersunk hole 71 connects to a round steel column 72, which is then sheathed with a perforated round steel bar 74. A disc spring assembly 73 is positioned between the end surface of the perforated round steel bar 74 and the bottom surface of the countersunk hole 71 and sheathed on the round steel column 72. The disc spring assembly 73 comprises a plurality of disc spring plates 730 stacked in opposite directions. When the upper pressure block 41 presses the coil 3 downward in the Z direction, the perforated round steel bar 74 contacts and compresses the disc spring assembly 73. The disc spring assembly 73 is sheathed on the round steel column 72 to ensure concentricity. The maximum compression of the disc spring assembly 73 should be greater than the initial distance H between the top surface of the round steel column 72 and the perforated round steel bar 74. A shim 732 may also be placed at the bottom of the disc spring assembly 73. The compression stroke of the disc spring assembly 73 can be adjusted by adjusting the number of shims 732 or disc spring plates 730.

[0037] In this embodiment, a support plate 8 is connected between the top surface of the upper pressure block 41 and the bottom surface of the upper clamp 1. The support plate 8 has a parallel groove 81 formed therein that matches the outer diameter of the perforated round steel 74. The perforated round steel 74 can be inserted into the parallel groove 81 and restrained. One end of the parallel groove 81 is open, and the perforated round steel 74 on the upper pressure block 41 can be slid through the opening for assembly. Compared with the screw hole and bolt assembly method in the prior art, it is simpler and does not generate burrs or iron filings.

[0038] Example 2: as shown in Figures 6 and 7.

[0039] This embodiment provides another specific implementation of the locking member, which is different from the first embodiment. The locking member 6 includes a locking groove 64 opened on the upper clamp 1 and a locking end 65 at the upper end of the pull plate 5. The locking end 65 can be embedded in the locking groove 64, and the locking end 65 and the locking groove 64 are locked by the locking surface 65 that contacts each other to lock the Z-direction relative displacement between the pull plate 5 and the upper clamp 1. An X-direction clamping screw 101 is also connected between the upper clamp 1 and the lower clamp 2.

[0040] A typical implementation is that the locking groove 64 is a dovetail groove 641, and the locking end 65 is a dovetail tenon 651 that cooperates with the dovetail groove 641. During specific operation, the dovetail groove 641 on the upper clamp 1 and the dovetail tenon 651 on the pull plate 5 are first offset by 1 to 2 mm in the X direction so that the two do not interfere with each other when they are relatively close to each other in the Z direction. Then a Z-direction force is applied to the upper clamp 1. At this time, the upper clamp 1 moves in the Z direction under the force, and the coil 3 is pressed by the elastic pressure block 4. Then start tightening the X-direction clamping screw 101, so that a pair of upper clamps 1 are relatively close to each other in the X direction until the dovetail tenon 651 is embedded in the dovetail groove 641. At this time, the inclined surface where the dovetail tenon 651 and the dovetail groove 641 contact each other serves as a locking surface 65 to provide a Z-direction relative displacement locking force between the pull plate 5 and the upper clamp 1.

[0041] Example 3: as shown in Figures 6 and 8.

[0042] This embodiment is a variation of the second embodiment. The locking groove 64 is a T-slot 642, and the locking end 65 is a T-shaped end 652 that mates with the T-slot 642. The operation is consistent with the second embodiment. After the T-shaped end 652 is inserted into the T-slot 642, the locking surface 65 becomes the horizontal surface where the T-slot 642 and the T-shaped end 652 contact each other.

[0043] Embodiment 4: As shown in FIG1 and FIG9 , this embodiment provides a transformer body pressing operation device for the above-mentioned embodiment.

[0044] Specifically, it includes an upper clamp 9 and a lower clamp 10, which are connected by a Z-direction clamping screw 102. The lower clamp 2 is placed on the lower clamp 10, and a pressure device is connected between the upper clamp 9 and the upper clamp 1. The upper end of the pressure device is connected to the upper clamp 9, and the lower end applies a Z-direction force to the upper clamp 1 through a pressure plate 11. During operation, the transformer coil 3, which has been assembled with the upper clamp 1 and the lower clamp 2, is first hoisted and placed on the lower clamp 10. The lower clamp 10 is then connected and tightened to the lower clamp 10 via the Z-direction clamping screw 102. At this time, the Z-direction spacing between the upper clamp 9 and the lower clamp 10 is fixed. The pressure device is then placed between the upper clamp 1 and the upper fixture 9, with both ends of the pressure device in contact with the upper clamp 1 and the upper fixture 9, respectively. The pressure device is operated to provide support force between the upper clamp 1 and the upper fixture 9 in the Z direction. Under this force, the upper clamp 1 is pressed downward in the Z direction. After the coil 3 is compressed, the locking member 6 is locked to maintain the compression force. The upper fixture 9, lower fixture 10, and the pressure device can then be removed. Finally, the compressed transformer is hoisted away from the lower fixture 10 to complete the entire compression operation.

[0045] A typical pressurizing device is a jack 12 placed between the upper clamp 9 and the upper clamp 1, or a pressurizing screw 13 connected between the upper clamp 9 and the upper clamp 1. Taking the jack 12 as an example, the pressing operation process of the first embodiment is to place the jack 12 between the upper clamp 1 and the pressure plate 11, and the pressure plate 11 is overlapped between a pair of upper clamps 1. The jack 12 provides Z-direction support force to press the upper clamp 1Z downward through the pressure plate 11 until the pin hole 1 61 and the pin hole 2 62 overlap, and then the pin shaft 63 is inserted into the pin hole 1 61 and the pin hole 2 62 to complete the Z-direction locking. In the second embodiment, when the dovetail tenon 651 and the dovetail groove 641 can overlap in the X direction, the clamping screw 101 is locked so that the dovetail tenon 651 is embedded in the dovetail groove 641 to complete the Z-direction locking.

[0046] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0047] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A pressing structure for the transformer body, comprising an upper clamping member (1) and a lower clamping member (2). A coil (3) is located between the upper clamping member (1) and the lower clamping member (2). An elastic pressing block (4) is also connected between the upper clamping member (1) and / or the lower clamping member (2) and the coil (3). It is characterized in that: A pull plate (5) is also connected between the upper clamping piece (1) and the lower clamping piece (2). The lower end of the pull plate (5) is fixedly connected to the lower clamping piece (2), and the upper end of the pull plate (5) is connected to the upper clamping piece (1) through a locking member (6). After the upper clamping piece (1) and the upper end of the pull plate (5) are connected through the locking member (6), the Z-direction relative displacement between the pull plate (5) and the upper clamping piece (1) is locked.

2. The pressing structure for the transformer body according to claim 1, characterized in that: The locking member (6) includes a first pin hole (61) opened on the upper clamping piece (1), a second pin hole (62) opened on the upper end of the pull plate (5), and a pin shaft (63) that can penetrate through the first pin hole (61) and the second pin hole (62).

3. The pressing structure for the transformer body according to claim 2, characterized in that: The locking member (6) includes a locking groove (64) opened on the upper clamping piece (1) and a locking end (65) at the upper end of the pull plate (5). The locking end (65) can be embedded in the locking groove (64), and the Z-direction relative displacement between the pull plate (5) and the upper clamping piece (1) is locked through the locking surfaces (65) in contact with each other between the locking end (65) and the locking groove (64). An X-direction clamping screw (101) is also connected between the upper clamping piece (1) and the lower clamping piece (2).

4. The pressing structure for the transformer body according to claim 3, characterized in that: The locking groove (64) is a dovetail groove (641), and the locking end (65) is a dovetail tenon (651) that cooperates with the dovetail groove (641).

5. The pressing structure for the transformer body according to claim 3, characterized in that: The locking groove (64) is a T-shaped groove (642), and the locking end (65) is a T-shaped end head (652) that cooperates with the T-shaped groove (642).

6. The pressing structure for the transformer body according to claim 1, characterized in that: The elastic pressing block (4) includes an upper pressing block (41) and a lower pressing block (42). The upper pressing block (41) is located between the upper clamping piece (1) and the top of the coil (3), and the lower pressing block (42) is located between the lower clamping piece (2) and the bottom of the coil (3). The upper pressing block (41) is connected to the upper clamping piece (1) through a buffer member (7).

7. The pressing structure for the transformer body according to claim 6, characterized in that: The top surface of the upper pressing block (41) has a counterbore (71). A round steel column (72) is connected to the center of the counterbore (71). The round steel column (72) is sleeved with an open-hole round steel (74). A disc spring group (73) sleeved on the round steel column (72) is provided between the end face of the open-hole round steel (74) and the bottom surface of the counterbore (71).

8. The pressing structure for the transformer body according to claim 7, characterized in that: A support plate (8) is also connected between the top surface of the upper pressing block (41) and the bottom surface of the upper clamping piece (1). Parallel grooves (81) that match the outer diameter of the open-hole round steel (74) are opened on the support plate (8).

9. A pressing operation device for the transformer body, characterized in that: Specifically for the transformer body pressing structure described in any one of claims 1 to 8, it includes an upper fixture (9) and a lower fixture (10). The upper fixture (9) and the lower fixture (10) are connected through a Z-direction clamping screw (102); the lower clamping piece (2) is placed on the lower fixture (10), and a pressurizing device is connected between the upper fixture (9) and the upper clamping piece (1). The upper end of the pressurizing device is connected to the upper fixture (9), and the lower end applies a Z-direction acting force to the upper clamping piece (1) through a pressure plate (11).

10. The pressing operation device for the transformer body according to claim 9, characterized in that: The pressurizing device is a jack (12) placed between the upper fixture (9) and the upper clamping piece (1) or a pressurizing screw (13) connected between the upper fixture (9) and the upper clamping piece (1).

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