Anti-vibration fixing device of high-voltage foil winding new process dry-type transformer

Abstract

The invention discloses an anti-vibration fixing device of a high-voltage foil winding new process dry-type transformer, and relates to the technical field of transformers, the anti-vibration fixing device comprises a supporting base, an adjustable supporting screw rod assembly and a multi-stage elastic damping assembly, the lower end of the adjustable supporting screw rod assembly is connected with the supporting base, and the upper end of the adjustable supporting screw rod assembly is connected with the multi-stage elastic damping assembly; the multi-stage elastic damping assembly is arranged between the adjustable supporting screw assembly and the coil end cover in series and used for absorbing axial vibration generated in the operation process of the coil, and an annular clamping base is installed on the side wall of the coil and used for restraining the radial direction of the coil and absorbing radial vibration. A guide positioning block is installed between the bottom of the coil and the supporting base. By installing the multi-stage elastic damping assembly, the function of segmented absorption and attenuation of coil operation vibration is achieved, the problem that a traditional single elastic element can only work in a limited frequency band and cannot suppress full-frequency-band vibration from dozens of hertz to hundreds of hertz at the same time is solved, the vibration isolation frequency band width is effectively expanded, noise is remarkably reduced, and the vibration isolation effect is improved. And the service lives of the coil and the box body are prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of transformers, and specifically to an anti-vibration fixing device for a new process dry-type transformer with high-voltage foil winding. Background Technique

[0002] Existing high-voltage foil-wound dry-type transformers usually use processes such as full immersion of epoxy resin or vacuum pressure injection to fix the foil-wound coil structure inside the iron core, and are installed at intervals with the outer shell by means of heat dissipation grooves. However, with the development of foil winding technology, the coil structure is thin and long, and its mechanical rigidity becomes poor. When the transformer is energized and operating, due to the action of electromagnetic excitation and the iron core magnetic field, the coil will generate relative vibration, resulting in problems such as high transformer noise, poor stability, and inconvenient maintenance.

[0003] Patent CN116092783B discloses a dry-type transformer for marine ship power distribution with anti-vibration function. The above patent achieves good stability during marine operation.

[0004] The above patent can keep the voltage transformation device in a stable state when at sea by setting an arc-shaped slide rail, a limit frame, a first support frame and a first fixing plate. When the ship is bumping at sea, the limit frame will slide on the outer surface of the arc-shaped slide rail, thus playing an effect of keeping the voltage transformation device stable. However, it cannot effectively solve the vibration generated during the operation of the transformer itself.

[0005] Therefore, this application proposes an anti-vibration fixing device for a new process dry-type transformer with high-voltage foil winding, which can effectively buffer the vibration generated during the operation of the transformer coil. Summary of the Invention

[0006] The purpose of the present invention is to provide an anti-vibration fixing device for a new process dry-type transformer with high-voltage foil winding, so as to solve the technical problem that the coil will generate relative vibration due to the action of electromagnetic excitation and the iron core magnetic field mentioned in the above background technique.

[0007] To achieve the above purpose, the present invention provides the following technical solution: An anti-vibration fixing device for a new process dry-type transformer with high-voltage foil winding, including a support base, an adjustable support screw component and a multi-stage elastic damping component. The support base is used to be fixed at the bottom of the transformer box body and carry the coil. The lower end of the adjustable support screw component is connected to the support base, and the upper end is in threaded cooperation with the coil end cover, and is used for axially supporting the coil. The multi-stage elastic damping component is serially arranged between the adjustable support screw component and the coil end cover, and is used for absorbing the axial vibration generated during the operation of the coil. A ring-shaped clamping seat is installed on the side wall of the coil, and the ring-shaped clamping seat is connected to the multi-stage elastic damping component, and is used for radially restraining the coil and absorbing the radial vibration. A guiding and positioning block is installed between the bottom of the coil and the support base, and the guiding and positioning block is used for preliminary positioning and limiting of the coil in the radial and horizontal directions.

[0008] Preferably, the support base is bent from cold-rolled steel plate with a plate thickness of 4-8 mm. Transverse stiffeners are provided inside the support base to improve rigidity. After phosphating treatment on the surface of the support base, epoxy zinc-rich primer and polyurethane topcoat are sprayed. A number of screw holes are reserved on the support base for installing the adjustable support screw assembly, and grooves for inserting the guiding positioning blocks are opened at corresponding positions.

[0009] Preferably, the adjustable support screw assembly includes: a screw, a pre-tightening nut, a spring preloading assembly and an elastic sealing sleeve;

[0010] The screw is a galvanized threaded steel rod with a diameter of 12 mm. The pre-tightening nut is an M12×1.25 hexagon nut. The spring preloading assembly is sleeved outside the screw and used to generate a continuous pre-tightening force between the pre-tightening nut and the support base. The elastic sealing sleeve is sleeved outside the screw and used for dust prevention and restricting the lateral swing of the spring preloading assembly.

[0011] Preferably, the spring preloading assembly includes:

[0012] A helical compression spring, made of carbon steel wire after nickel plating, with a wire diameter of 5 mm, an outer diameter of 20 mm and a free length of 30 mm. One end abuts against the bottom surface of the pre-tightening nut, and the other end abuts against the support base;

[0013] A lock washer is placed between the pre-tightening nut and the support base. The toothed structure of the lock washer generates frictional force under vibration conditions to prevent the pre-tightening nut from loosening;

[0014] When the pre-tightening nut is tightened to the designed position, the helical compression spring generates a pre-compression of 5-10 mm, so that a clamping force is maintained between the pre-tightening nut and the screw, and at the same time, axial micro-vibrations are buffered.

[0015] Preferably, the elastic sealing sleeve is made of chloroprene rubber. The lower end is clamped on the positioning step of the support base, and the upper end fits along the outer surface of the screw to the bottom circumference of the pre-tightening nut, forming a sealed dust-proof structure, and laterally restricting the helical compression spring when the helical compression spring is subjected to a lateral force.

[0016] Preferably, the multi-stage elastic damping assembly includes, from top to bottom in sequence:

[0017] A rubber cushion layer, made of hydrogenated nitrile rubber, with a hardness of 60 Shore A and a thickness of 5-8 mm. The hollow inner hole matches the diameter of the screw and is fixed to the convex platform at the bottom of the coil end cover by screws;

[0018] A metal helical spring, made of carbon steel, with a wire diameter of 5 mm, an outer diameter of 20 mm and a height of 25 mm, surface nickel-plated. The upper end of the spring is meshed with the lower surface of the rubber cushion layer through a plastic retaining ring, and the lower end is clamped in the bottom groove of the silicone grease damping block;

[0019] The silicone grease damping block includes a damping unit composed of a 1.5-mm-thick sheet metal housing and internal silicone grease. Its external shape is like an oil pressure damping cylinder without a piston. The upper plane fits against the lower end of the metal helical spring, and the lower part is connected to the screw through a fixed boss.

[0020] Preferably, the annular clamping seat is formed by splicing six equally divided sector-shaped clamping blocks. Each sector-shaped clamping block includes:

[0021] A U-shaped groove is opened on one side wall for the side wall of the environmentally friendly foil winding coil;

[0022] A 2-mm-thick PTFE gasket is pasted on the inner side of the U-shaped groove to reduce friction, and a 3-mm-thick elastic shock-absorbing cotton block is embedded at the bottom of the U-shaped groove to absorb shock;

[0023] At least two bolt holes are arranged on the outside for bolt fixation with the connecting plate to form a complete annular structure;

[0024] The sector-shaped clamping blocks are spliced together by bolt buckles, and the included angle is 60°.

[0025] Preferably, the connecting plate is a rectangular steel plate. One end is connected to the bolt hole on the outside of the sector-shaped clamping block through an M8 bolt, and the lower end is connected to the upper fixed boss of the silicone grease damping block through a pull rod. The pull rod is an M8×160 - 200-mm screw, equipped with a spring washer and a nylon lock nut to adjust the radial pre-tightening force of the annular clamping seat on the side wall of the coil.

[0026] Preferably, the guiding and positioning block includes an upper block and a lower block:

[0027] The upper block is an annular positioning part made of injection-molded PA66 material, installed on the bottom edge of the coil, and fits against the bottom surface of the coil to achieve radial positioning;

[0028] The lower block is a concave-shaped positioning part made of corresponding PA66 material, embedded in the reserved groove of the support base, and cooperates with the upper block to achieve horizontal limit;

[0029] The guiding and positioning block enables the coil to automatically obtain double positioning in the radial and horizontal directions during installation through their respective shape fittings.

[0030] Preferably, the pre-tightening nut on the adjustable support screw assembly and the lock nut on the pull rod of the annular clamping seat are both adjustable, so that the pre-compression deformation amount of the multi-stage elastic damping assembly and the annular clamping seat is maintained in the range of 5 - 10 mm to ensure sufficient vibration isolation margin and thermal expansion compensation ability during the operation of the transformer.

[0031] Compared with the prior art, the beneficial effects of the present invention are:

[0032] 1. The present invention realizes the function of segmentally absorbing and attenuating the vibration of the coil during operation by installing a multi-stage elastic damping component, solving the problem that the traditional single elastic element can only work in a limited frequency band and it is difficult to simultaneously suppress the vibration in the full frequency band from dozens of hertz to hundreds of hertz; high-frequency vibration often directly transmits to the outer shell, generating noise and resonance. It effectively expands the vibration isolation frequency band width. The low-frequency vibration force is absorbed by the rubber pad, the medium-frequency is attenuated by the metal spring, and the high-frequency is consumed by the silicone grease flow damping, significantly reducing the noise and prolonging the service life of the coil and the box body;

[0033] 2. The present invention realizes buffering of minute axial jumps during vibration by installing a helical compression spring and a lock washer, solving the problem that ordinary threaded connections are prone to loosen or even fall off under the action of electromagnetic excitation and thermal expansion, resulting in support failure and coil misalignment, so that the transformer connecting parts always maintain stable clamping during vibration and temperature changes, improving the reliability of the device;

[0034] 3. The present invention realizes elastic constraint on the coil, reduces friction and improves impact buffering by installing an annular clamping seat, a PTFE gasket and elastic shock cotton, solving the problem that traditional rigid clamping or non-buffered design is prone to cause foil surface indentation and abrasion, further attenuating the radial vibration energy, and improving the structural integrity and operation safety of the coil;

[0035] 4. The present invention realizes the effect of integrated assembly by installing a guiding positioning block and an adjustable support screw component, solving the problem that large-size foil-wound coils are prone to position deviation during assembly and operation and require multiple debugging; traditional positioning mostly relies on external tools or bonding, with insufficient accuracy and inconvenient disassembly and maintenance, ensuring that the coil can still maintain a stable position under the conditions of thermal expansion and vibration, and reducing the failure rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is the front view structural schematic diagram of the present invention;

[0037] Figure 2 is the front structural schematic diagram of the present invention;

[0038] Figure 3 is the structural schematic diagram of the multi-stage elastic damping component of the present invention;

[0039] Figure 4 is the structural schematic diagram of the sector-shaped clamping block of the present invention;

[0040] [[ID=3o]] Figure 5 is the structural schematic diagram of the bolt buckle of the present invention;

[0041] Figure 6 is the structural schematic diagram of the guiding positioning block of the present invention;

[0042] Figure 7 is the structural schematic diagram of the adjustable support screw component of the present invention;

[0043] Figure 8 This is a schematic structural diagram of the multi - stage elastic damping component of the present invention.

[0044] In the figure: 1. Bottom of the transformer box; 2. Support base; 3. Screw; 4. Coil end cover; 5. Coil; 6. Multi - stage elastic damping component; 7. Bolt buckle; 9. Sector clip; 10. U - shaped groove; 11. PTFE gasket; 12. Elastic impact cotton block; 13. Bolt hole; 15. Upper block; 16. Lower block; 17. Groove; 18. Pre - tightening nut; 19. Elastic sealing sleeve; 20. Helical compression spring; 21. Lock washer; 22. Tie rod; 23. Rubber cushion layer; 24. Metal helical spring; 25. Silicone grease damping block; 26. Connecting plate. Specific embodiments

[0045] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

[0046] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "front end", "rear end", "both ends", "one end", "the other end", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention 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, so it cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0047] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" 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 directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0048] Embodiment 1: Please refer to Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7and Figure 8 , an anti-vibration fixing device for a new high-voltage foil-wound dry-type transformer. Fix the support base 2 to the bottom 1 of the transformer box body with M12 bolts, adjust the horizontal error within ±0.5 mm. Insert 8 screw rods 3 from the lower holes of the support base 2. First, put on the elastic sealing sleeve 19, and the lower end is stuck on the support pad. Then install the lock washer 21 and the pre-tightening nut 18, but do not lock them temporarily. Place the high-voltage foil-wound coil 5 together with the coil end cover 4 on the support base 2. The bottom edge of the coil 5 is in contact with the upper block 15. The upper block 15 automatically inserts into the groove 17 of the support base 2 and cooperates with the lower block 16 to achieve radial and horizontal positioning. Tighten the pre-tightening nut 18 one by one until the bottom surface of the pre-tightening nut 18 compresses the helical compression spring 20 to a predetermined height (pre-compression of 6 mm) until there is a slight friction between the pre-tightening nut 18 and the support base 2 but it can be adjusted. At this time, the helical compression spring 20 maintains elastic pre-tightening between the pre-tightening nut 18 and the support base 2. Fix the rubber cushion layer 23 to the reserved boss below the coil end cover 4 with M5 screws. Then place the metal helical spring 24 below the rubber cushion layer 23, and make the lower end of the metal helical spring 24 snap into the bottom notch of the silicone grease damping block 25. Finally, fit the upper fixing boss of the silicone grease damping block 25 with the upper end of the screw rod 3, and lock it with a φ12×20×2 mm cylinder washer and a nylon lock nut, that is, complete the installation of the multi-stage elastic damping component 6. Assemble 6 sector-shaped clamping blocks 9 around the side wall of the coil 5 and connect them with the connecting plate 26 with M8 high-strength bolts, ensuring that the inner diameter of the thick ring after the sector-shaped clamping blocks 9 are assembled is 500 mm. Then pass the pull rod 22 through the lower end of the connecting plate 26 and thread it with the upper fixing boss of the silicone grease damping block 25, and adjust the lock nut so that the sector-shaped clamping blocks 9 generate a radial pre-tightening force of 100 N on the side wall of the coil 5. Check the pre-compression of each elastic element: the pre-compression stress of the helical compression spring 20 is 6 mm ± 0.5 mm, and there should be a pre-shrinkage of about 2 mm between the rubber cushion layer 23 and the metal helical spring 24. After the pull rod 22 is adjusted, the gap between the sector-shaped clamping blocks 9 and the side wall of the coil 5 is 0, and the pre-tightening force is stable at 100 ± 10 N, ensuring the overall assembly level of the machine. The coil 5 can move slightly up and down axially within a range of ±1 mm;

[0049] When the dry-type transformer is energized and operating, the high-voltage foil-wound coil 5 generates electromagnetic excitation and thermal expansion: the axial vibration is preferentially absorbed by the rubber cushion layer 23 for vibrations within the range of 0 - 50 Hz, the vibrations from 50 - 200 Hz are mainly attenuated by the metal helical spring 24, and the high-frequency vibrations above 200 Hz are dissipated by the flow damping of the silicone grease inside the silicone grease damping block 25. The series connection of the three layers of damping reduces the amplitude of vibration transmitted to the box body by more than 70%; the radial vibration is buffered by the annular clamping seat through the PTFE 11 and the elastic shock cotton block 12, and is connected to the silicone grease damping block 25 through the pull rod 22 to introduce the radial impact energy into the metal helical spring 24 and the rubber cushion layer 23 for further attenuation; due to the pre-tightening of the helical compression spring 20, the connection state between the screw rod 3 and the pre-tightening nut 18 always remains stable and will not become loose due to vibration or thermal expansion. The elastic sealing sleeve 19 ensures that the helical compression spring 20 does not swing laterally and is dust-proof. The guiding and positioning block ensures that the coil 5 can freely compensate for thermal expansion within the range of ±1 mm longitudinally without jamming or deviation.

[0050] Embodiment 2: Please refer to Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 , an anti-vibration fixing device for a new high-voltage foil-wound process dry-type transformer, the number of transverse reinforcing ribs of the support base 2 is increased to 4, the lock washer 21 is replaced with a toothed disc spring washer to enhance the anti-loosening force, the material of the sector-shaped clamping block 9 of the elastic sealing sleeve 1 is changed to thermoplastic polyurethane, the material of the rubber cushion layer 23 is changed to silicone rubber and is fixed to the boss of the coil end cover 4 by three M5×1 mm stainless steel screws to increase the contact area, and the upper surface is provided with anti-slip fine lines. The outer shell of the silicone grease damping block 25 is changed to a 2 mm stainless steel plate bent into a rust-free damping cylinder, filled with 60,000 cSt high-viscosity silicone grease. The number of sector-shaped clamping blocks 9 is changed to 8 and the material is changed to aluminum alloy plate, with a central angle of 45° each. The size of the U-shaped groove 10 remains unchanged, and a 2 mm thick nylon bushing is pasted on the inner side, and the bottom is changed to a 4 mm thick closed-cell sponge pad to enhance the buffering performance;

[0051] The support base 2 is fixed to the bottom 1 of the transformer tank by M12 bolts. Eight screw rods 3 sequentially pass through the screw holes of the support base 2, with elastic sealing sleeves 19 sleeved on them. Disc-shaped lock washers and self-locking nuts are placed for preliminary locking. The coil 5 and the coil end cover 4 are placed on the support base 2 and pre-positioned by the upper block 15 and the lower block 16. The pre-tightening nut 18 is tightened, and the helical compression spring 20 is compressed by about 7 mm for preloading. The rubber cushion layer 23, the metal helical spring 24, and the silicone grease damping block 25 are installed and locked. Eight sector-shaped clamping blocks 9 are assembled and locked with the connecting plate 26 and the pull rod 22. The radial force is adjusted to 120 N ± 10 N, and it is checked that the three-layer damping preloads are respectively: the rubber cushion layer 23 is compressed by 3 mm, the metal helical spring 24 is compressed by 8 mm, and the initial internal gap of the silicone grease damping block 25 is 1 mm;

[0052] Since the silicone rubber cushion layer can still maintain elasticity at low temperatures (-20°), this embodiment is applicable to cold climate regions. After the stiffness of the metal helical spring 24 increases, it absorbs medium and high frequency vibrations in the range of 50 - 250 Hz more thoroughly. The combination of the aluminum alloy plate and the nylon bushing effectively reduces the weight of the annular clamping seat itself and reduces the additional force on the coil 5. The high-viscosity silicone grease damping block 25 further enhances the high-frequency suppression ability above 300 Hz, and the vibration transmission is reduced by more than 75%.

[0053] Embodiment 3: Please refer to Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 , an anti-vibration fixing device for a new process dry-type transformer with high-voltage foil winding. This embodiment is designed for the anti-vibration fixing device of a small dry-type transformer (the outer diameter of the coil 5 is 400 mm and the total height is 700 mm), and is mainly optimized in terms of structural compactness and lightweight:

[0054] The support base 2 has dimensions of 600 mm × 450 mm and a plate thickness of 4 mm; it is only equipped with two transverse stiffeners; the coating method is the same as that of Example 1; 6 screw holes are reserved; grooves 17 are opened on both sides of the middle of the support base 2, and there are 6 screw rods 3 in total for the adjustable support screw assembly; the pre-tightening nut 18 is M10×1.25 with nylon locking; the lock washer 21 is a disc spring washer; the material of the elastic sealing sleeve 1 and the sector clip 9 is EPDM rubber; the coil end cover 4 is welded and processed from carbon steel plate, and is provided with 6 M10 threaded holes; the surface of the bottom boss is sprayed with epoxy resin paint; in the multi-stage elastic damping assembly 6, the rubber cushion 23 is made of nitrile rubber (NBR), with a hardness of 65 Shore A, and is fixed to the end cover boss by two M4×12 mm screws. The metal helical spring 24 is made of carbon steel; nickel-plated; with a stiffness of about 30 N / mm; the upper end is stuck under the rubber pad by a plastic retaining ring, and the lower end is inserted into the bottom groove of the silicone grease damping block 25; the outer shell material of the silicone grease damping block 25 is aluminum alloy (6063), with a thickness of 1.2 mm and an anodizing treatment; the inside is filled with 40,000 cSt high-viscosity silicone grease; the upper part is fitted with the metal helical spring 24, and the lower fixed boss is matched with the screw rod 3, and is locked with an aluminum washer and a nylon lock nut; the material of the sector clip 9 is 3 mm thick aluminum alloy plate (6061-T6); the dimensions of the U-shaped groove 10 are: width 10 mm × depth 5 mm, and a 1.5 mm thick PTFE gasket 11 is pasted on the inner side. A 2 mm thick EVA foam is embedded at the bottom of the U-shaped groove 10; a M8×20 mm bolt hole 13 is provided on the outside of the sector clip 9 and is fixed to one side of the connecting plate 26. The connecting plate 26 is made of an aluminum plate with a width of 25 mm × a length of 100 mm × a thickness of 3 mm; it is connected to the sector clip 9 by an M8×20 mm stainless steel bolt, and the lower end is matched with the pull rod 22. The pull rod 22 is equipped with a spring washer and a nylon lock nut, and the radial adjustment force is about 80 N; the upper block 15 is injection-molded from PA6, with an inner diameter of 400 mm, an outer diameter of 410 mm, and a thickness of 8 mm, and is provided with 3 positioning teeth with a width of 5 mm × a length of 8 mm. The lower block 16 is injection-molded from PA6, with an outer diameter of 410 mm, an inner diameter of 400 mm, and a thickness of 6 mm, and the groove dimensions are 5 mm × 8 mm;

[0055] The support base 2 is fixed to the inner bottom of the bottom 1 of the transformer box body → 6 screw rods 3 pass through the holes → an EPDM elastic sealing sleeve 19 is sleeved → a disc lock washer 21 → the pre-tightening nut 18 is initially locked. Place the coil 5 and the coil end cover 4 on the support base 2 → the upper block 15 and the lower block 16 of the guide block are in place, and the pre-tightening nut 18 is tightened one by one to pre-compress the helical compression spring 20 by about 5 mm. Install the rubber cushion 23, the metal helical spring 24, and the silicone grease damping block 25 and lock them. Assemble 6 sector clips 9, lock them with the connecting plate 26 and the pull rod 22, and adjust the radial force to 80 N ± 8 N. Check: Adjust the foot pads to make the overall horizontal error < ±0.5 mm, the metal helical spring 24 is pre-compressed by 5 mm ± 0.5 mm, the rubber cushion 23 is compressed by 2 mm, and the gap of the silicone grease damping block 25 is 1 mm;

[0056] The structure has a compact size. The overall height of the machine is 750 mm, which only occupies a limited space inside the box. The spring stiffness is relatively low, suitable for dry-type transformers with low power (<250 kVA). It can effectively absorb low-frequency vibrations in the range of 0 - 150 Hz. The aluminum alloy damping block and aluminum clamping block further reduce the weight, making the total weight of the components decrease by about 20% (compared with the helical compression spring), reducing the load on the support base. The guiding and positioning block is simple and low-cost, with a preliminary positioning accuracy of ±0.5 mm for the coil, and the installation efficiency is increased by 30%.

[0057] Example 4: Please refer to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 、 Figure 7 and Figure 8 , an anti-vibration fixing device for a new high-voltage foil-wound dry-type transformer. The elastic sealing sleeve 19 is changed to fluororubber material. The lock washer 21 is a toothed spring washer. The material of the rubber cushion layer 23 is silicone composite polyurethane. The fixing method is the same as that in Example 1. Replace the silicone grease damping block 25 with a pneumatic damper, which is a micro pneumatic damping cylinder with an outer diameter of φ20 mm, a length of 40 mm, and an inner diameter of φ12 mm, without the piston rod exposed. The damping oil cavity is filled with pneumatic oil (the damping ratio is adjustable), and the upper end contacts the lower end of the metal helical spring 24. The lower end has a steel fixing boss, which is connected to the upper part of the screw 3 and locked through a φ12 mm×φ20 mm×2 mm steel washer and a nylon lock nut. The internal damping coefficient of this pneumatic damper can be adjusted through the M4 inflation valve at the top to achieve adjustable absorption of vibrations in different frequency bands. The elastic shock cotton block 12 is changed to EVA foam. The support base 2 is fixed on the bottom 1 of the transformer box. Install 8 screws 3, put on the fluororubber elastic sealing sleeve 19, install the lock washer 21, and initially lock it through the pre-tightening nut 18. Place the coil 5 and the coil end cover 4 on the support base 2, position the upper block 15 and the lower block 16, tighten the pre-tightening nut 18, so that the helical compression spring 20 is pre-compressed by about 6 mm. Install the rubber cushion layer 23, the metal helical spring 24, and the silicone grease damping block 25. Replace the silicone grease damping block 25 with a pneumatic damper. The lower boss of the pneumatic damper is sleeved on the screw 3, and it is rotationally locked with the pre-tightening nut 18 and the lock washer 21. Assemble 8 sector-shaped clamping blocks 9, connect them to the lower fixed boss of the pneumatic damper through the connecting plate 26. Adjust the lock nut of the pull rod 22 so that the radial force reaches 110 N±10 N for the PTFE gasket. Adjust the internal damping pressure through the M4 inflation valve at the top of the pneumatic damper so that the damping force for vibrations in the range of 150 - 300 Hz is continuously adjustable within the range of 200 - 500 N·s / m for the helical compression spring. Check: The locking torque of all nuts is 20 N·m±2 N·m. The pre-compression of the three-layer damping is respectively: 3 mm for the silicone rubber cushion layer, 6 mm for the pre-compression of the metal helical spring 24, and 1 mm buffer gap is left inside the pneumatic damper;

[0058] The pneumatic damper can automatically adjust the damping ratio according to the on-site vibration spectrum, and is applicable to occasions where the vibration isolation performance needs to be frequently switched due to regional or load changes. After modification, it can accurately adjust high-frequency vibrations of 100 - 400 Hz, and the vibration transmission reduction amplitude reaches 80%. The fluororubber elastic sealing sleeve 19 can withstand high temperatures above 150 °C, and is suitable for environments with large temperature fluctuations. The POM guide block has a low friction coefficient and good wear resistance, and can maintain a positioning accuracy of ±0.5 mm for a long time.

[0059] Example 5: Please refer to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 、 Figure 7 and Figure 8 and Figure 8 , an anti-vibration fixing device for a new type of high-voltage foil-wound dry-type transformer. In this embodiment, on the basis of a small transformer, the support base and the guiding positioning block are integrally designed, and a shape memory alloy elastic element is added to the multi-stage damping component to improve the thermal expansion compensation ability and overall reliability:

[0060] Integrated support base 2 and guiding positioning block: A 6 mm thick aluminum alloy plate (6061-T6) is bent into an integral support base with an outer dimension of 650 mm × 500 mm; on both sides of the center of the bottom surface, a pair of concave positioning grooves (each 90 mm × 15 mm for the upper block) are provided, and the bottom surface of the groove is coplanar with the external bottom plate; the guiding positioning block is cast integrally with the base, and the local structure is convex: the convex height is 8 mm × 12 mm × 80 mm, corresponding to the positioning groove at the bottom of the coil, and the positioning accuracy is ±0.3 mm; the whole is treated with anodic oxidation to prevent corrosion; two 30 mm × 6 mm aluminum profile reinforcing ribs are welded to the inner wall of the base to enhance rigidity; 6 φPTFE gasket 11 mm screw holes are reserved for installing the adjustable support screw component;

[0061] The multi-stage elastic damping assembly 6 includes: a rubber pad 23: the material is a composite layer of NBR and shape memory alloy (SMA) sheets, the rubber thickness is 5mm, the SMA sheet thickness is 1mm, the outer diameter is φ28mm, and the inner hole is φ10.2mm; it is embedded in the end cover boss through a matching positioning ring and does not require screw fixation; a shape memory alloy elastic element: located below the rubber pad 23, and is composed of two Φ3 mm × 50mm long 0Cr18Ni9TiSMA wire and welded in parallel to the base boss. The length is designed to maintain a superelastic state at 20°C and can automatically adjust the preload force within the range of 20-80°C to provide thermal compensation. Metal coil spring 24: TN101 titanium alloy, wire diameter 4mm, outer diameter 16mm, height 22mm, stiffness 30N / mm; the upper end clamps the lower end of the shape memory alloy elastic element, and the lower end is clamped into the bottom groove of the silicone grease damping block 25; Silicone grease damping block 25: shell material 1.2mmSUS304, stainless steel bending; inner diameter φ16mm, height 18mm; filled with 45000cSt medical grade silicone grease; the upper end fits with the metal coil spring 24, the lower end boss φ10mm×height 5mm, docks with the screw 3, and is locked with a φ10mm×φ16mm×2mm stainless steel washer and a nylon locking nut;

[0062] The shape memory alloy elastic element has the superelastic performance of a coil compression spring at 20-80℃. It not only provides an elastic stiffness of 35N / mm at room temperature, but also automatically restores its shape and maintains a certain preload as the temperature rises, offsetting the deflection caused by thermal expansion of the coil; the titanium alloy spring can still maintain stable stiffness in a high temperature environment (80℃), while taking into account light weight and corrosion resistance; the integrated aluminum alloy base is combined with the guide positioning block to simplify the installation process, eliminating the need for additional alignment operations during installation, and saving 20% of the working hours of the coil compression spring; since the materials are all made of corrosion-resistant aluminum alloy, 316L stainless steel, and SUS304 stainless steel, the entire device can adapt to operating conditions of -40℃ to 120℃, and is suitable for use in corrosive environments such as coastal areas and chemical plants; the three-stage damping coupling design has an 85% vibration absorption efficiency in the full frequency band of 0-300Hz, effectively reducing noise and extending the service life of the transformer.

[0063] Working Principle: When the high-voltage foil coil 5 is powered on, it will generate electromagnetic excitation and thermal expansion, which concentrates stress in the axial direction. The helical compression spring 20 provides primary buffering for the axial micro-vibration. The rubber pad 23, metal helical spring 24, and silicone grease damping block 25 in the multi-stage elastic damping assembly 6 are connected in series to achieve step-by-step energy absorption and attenuation from low to high frequencies, preventing vibration from being directly transmitted to the transformer box.

[0064] The side wall of the coil 5 is vulnerable to radial impact and may shift. The segmented annular clamping seat surrounds the side wall of the coil 5 through multiple sector-shaped clamping blocks 9. The adjustable pull rod 22 is used to link the sector-shaped clamping blocks 9 with the silicone grease damping blocks 25 to provide uniform elastic restraint for radial vibration. The inner PTFE gasket 11 reduces friction, and the elastic shock-absorbing cotton block 12 absorbs transient shock energy, so that the radial vibration is gradually attenuated and fed back to the multi-stage damping system for further attenuation.

[0065] The guiding and positioning blocks perform two-way preliminary positioning of the coil 5 in the radial and horizontal directions during the assembly stage to ensure the positioning accuracy of the coil 5. At the same time, the helical compression spring 20 and the multi-stage elastic damping assembly 6 have movable buffer strokes when the temperature changes, and can automatically compensate for the small displacement of the coil 5 caused by thermal expansion and contraction, ensuring stable connection and no jamming.

[0066] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

Claims

1. An anti-vibration fixing device for a dry-type transformer with a new high-voltage foil winding process, comprising a support base (2), an adjustable support screw assembly, and a multi-stage elastic damping assembly (6), characterized in that: The support base (2) is used to be fixed at the bottom of the transformer box body (1) and bear the coil (5). The lower end of the adjustable support screw assembly is connected to the support base (2), and the upper end is in threaded cooperation with the coil end cover (4) for axially supporting the coil (5). The multi-stage elastic damping assembly (6) is serially arranged between the adjustable support screw assembly and the coil end cover (4) for absorbing the axial vibration generated by the coil (5) during operation. An annular clamping seat is installed on the side wall of the coil (5), and the annular clamping seat is connected to the multi-stage elastic damping assembly (6) for radially restricting the coil (5) and absorbing the radial vibration. A guiding and positioning block is installed between the bottom of the coil (5) and the support base (2), and the guiding and positioning block is used for initially positioning and limiting the coil (5) in the radial and horizontal directions.

2. The anti-vibration fixing device of a new high-voltage foil-wound dry-type transformer according to claim 1, characterized in that: The support base (2) is bent from cold-rolled steel plate with a plate thickness of 4-8 mm. Transverse stiffening ribs are provided inside the support base (2) to improve the stiffness. The surface of the support base (2) is sprayed with epoxy zinc-rich primer and polyurethane topcoat after phosphating treatment. A number of screw holes are reserved on the support base (2) for installing the adjustable support screw assembly, and grooves (17) for inserting the guiding and positioning blocks are opened at corresponding positions.

3. The anti-vibration fixing device of a new high-voltage foil-wound dry-type transformer according to claim 1, characterized in that: The adjustable support screw assembly includes: a screw (3), a pre-tightening nut (18), a spring preloading assembly and an elastic sealing sleeve (19); The screw (3) is a galvanized threaded steel rod with a diameter of 12 mm. The pre-tightening nut (18) is an M12×1.25 hexagonal nut. The spring preloading assembly is sleeved outside the screw (3) for generating a continuous pre-tightening force between the pre-tightening nut (18) and the support base (2). The elastic sealing sleeve (19) is sleeved outside the screw for dust prevention and restricting the lateral swing of the spring preloading assembly.

4. The anti-vibration fixing device of a new high-voltage foil-wound dry-type transformer according to claim 3, characterized in that: The spring preloading assembly includes: A helical compression spring (20) made of carbon steel wire after nickel plating treatment, with a wire diameter of 5 mm, an outer diameter of 20 mm and a free length of 30 mm. One end abuts against the bottom surface of the pre-tightening nut (18), and the other end abuts against the support base (2); A lock washer (21) is placed between the pre-tightening nut (18) and the support base (2). The toothed structure of the lock washer (21) generates frictional force under vibration conditions to prevent the pre-tightening nut (18) from loosening; When the pre-tightening nut (18) is tightened to the designed position, the helical compression spring (20) generates a pre-compression of 5-10 mm, so that a clamping force is maintained between the pre-tightening nut (18) and the screw (3), and at the same time, it buffers the axial micro-vibration.

5. The anti-vibration fixing device of a new high-voltage foil-wound dry-type transformer according to claim 3, characterized in that: The elastic sealing sleeve (19) is made of neoprene rubber. The lower end is clamped on the positioning step of the support base (2), and the upper end fits along the outer surface of the screw (3) to the bottom circumference of the pre-tightening nut (18) to form a sealed dust-proof structure, and laterally restricts the helical compression spring (20) when the helical compression spring (20) is subjected to a lateral force.

6. The anti-vibration fixing device of a new high-voltage foil-wound dry-type transformer according to claim 1, characterized in that: The multi-stage elastic damping assembly (6) includes successively from top to bottom: A rubber cushion layer (23) made of hydrogenated nitrile rubber, with a hardness of 60 Shore A and a thickness of 5-8 mm. The hollow inner hole matches the diameter of the screw (3), and is fixed on the bottom boss of the coil end cover (4) by screws; The metal helical spring (24) is made of carbon steel, with a wire diameter of 5 mm, an outer diameter of 20 mm, and a height of 25 mm. It is treated with nickel plating on the surface. The upper end of the spring engages with the lower surface of the rubber cushion layer (23) through a plastic retaining ring (8), and the lower end is clamped in the bottom notch of the silicone grease damping block (25). The silicone grease damping block (25) includes a damping unit composed of a sheet metal shell with a thickness of 1.5 mm and internal silicone grease. Its shape is like an oil pressure damping cylinder without a piston. The upper plane fits against the lower end of the metal helical spring (24), and the lower part is connected to the screw rod (3) through a fixed boss.

7. The anti-vibration fixing device of a new high-voltage foil-wound dry-type transformer according to claim 1, characterized in that: The annular clamping seat is formed by splicing six equally divided sector-shaped clamping blocks (9). Each sector-shaped clamping block (9) includes: A U-shaped groove (10) is opened on one side wall for the side wall of the environmentally friendly foil winding coil (5). A 2-mm-thick PTFE gasket (11) is pasted on the inner side of the U-shaped groove (10) to reduce friction, and a 3-mm-thick elastic shock-absorbing cotton block (12) is embedded at the bottom of the U-shaped groove (10) to absorb shock. At least two bolt holes (13) are provided on the outside for bolt fixation with the connecting plate (26) to form a complete annular structure. The sector-shaped clamping blocks (9) are spliced together through bolt buckles (7), and the included angle is 60°.

8. The anti-vibration fixing device of a new high-voltage foil-wound dry-type transformer according to claim 7, characterized in that: The connecting plate (26) is a rectangular steel plate. One end is connected to the bolt hole (13) on the outside of the sector-shaped clamping block (9) through an M8 bolt, and the lower end is connected to the upper fixed boss of the silicone grease damping block (25) through a pull rod (22). The pull rod (22) is an M8×160 - 200 mm screw rod, equipped with a spring washer and a nylon lock nut to adjust the radial pre-tightening force of the annular clamping seat on the side wall of the coil (5).

9. The anti-vibration fixing device of a new high-voltage foil-wound dry-type transformer according to claim 1, characterized in that: The guiding and positioning block includes an upper block (15) and a lower block (16): The upper block (15) is an annular positioning part made of injection-molded PA66 material, installed on the bottom edge of the coil (5), and fits against the bottom surface of the coil (5) to achieve radial positioning. The lower block (16) is a concave-shaped positioning part made of corresponding PA66 material, embedded in the reserved groove (17) of the support base (2), and cooperates with the upper block (15) to achieve horizontal limiting. The guiding and positioning block enables the coil (5) to automatically obtain double positioning in the radial and horizontal directions during installation through their respective shape matching.

10. The anti-vibration fixing device of a new high-voltage foil-wound dry-type transformer according to claim 1, characterized in that: The pre-tightening nut on the adjustable support screw rod assembly and the lock nut on the pull rod (22) of the annular clamping seat are both adjustable, so that the pre-compression deformation amount of the multi-stage elastic damping assembly (6) and the annular clamping seat is maintained in the range of 5 - 10 mm to ensure sufficient vibration isolation margin and thermal expansion compensation ability during the operation of the transformer.

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