Ventilation cooling structure for high-voltage winding and low-voltage winding of box-type transformer

Abstract

The invention relates to a box-type transformer high-low voltage winding ventilation cooling structure which comprises a transformer box body, a plurality of transformer three-phase cylinders, an iron core, an iron core upper clamping piece, an iron core lower clamping piece and a lower wind shield, and each transformer three-phase cylinder is arranged on the iron core in a surrounding mode; the iron core is arranged in the transformer box body through the iron core upper clamping piece and the iron core lower clamping piece; the lower wind shield is fixedly arranged in the transformer box body; the transformer box body is divided into an upper air outlet part and a lower air supply part by the lower wind shield; a plurality of air outlets are formed in the upper air supply part and the lower air outlet part of the transformer box body; a plurality of ventilation channels are formed in the transformer three-phase cylinder in the axial direction. The invention has the advantages that the heat dissipation efficiency of each winding is improved by increasing the convection heat dissipation area of epoxy resin and air; the air circulation path is reasonably designed, and air is fully utilized to take away heat, so that the temperature rise of the iron core and the winding is inhibited.

Description

Technical Field

[0001] The invention relates to the technical field of transformer winding potting, in particular to a ventilation and cooling structure for high and low voltage windings of a box-type transformer. Background Art

[0002] The transformer has a complex structure and is the core of the power system. Its operating status is related to whether the entire power system can operate smoothly. When the transformer is running, the internal core, coil and metal components will all produce losses, and the load changes will cause the transformer losses to change accordingly. All these losses will cause the transformer to heat up and the temperature to rise. Excessive temperature will reduce the efficiency of the transformer and shorten the life of the transformer. From the above analysis, it can be seen that the transformer cooling system plays a decisive role in whether the transformer can work normally.

[0003] The traditional transformer air cooling system adopts a closed design, and the utilization rate of the fluid domain in the box is low, which easily causes the transformer temperature to rise and malfunction, reducing the reliability of the transformer. At present, the use of high-permeability oriented silicon steel sheets and grain-oriented silicon steel sheets to manufacture the core has significantly improved the material properties, electrical and structural performance of silicon steel transformers. However, the high loss problem caused by the core and winding has not been effectively solved, and it is urgent to propose a ventilation cooling structure for high and low voltage windings of box-type transformers. Summary of the invention

[0004] Purpose of the Invention In the prior art, the box-type transformer adopts a closed design, the internal space is relatively closed, and the heat dissipation surface area is limited, resulting in lower heat dissipation efficiency than the open transformer. This may cause temperature rise problems during long-term operation or high load, affecting the performance and life of the transformer. In order to solve the above problems, the present invention proposes a new cooling system using epoxy resin potting technology for high and low voltage windings, which increases the heat dissipation area of ​​epoxy resin and air convection to improve the heat dissipation efficiency of the windings in each package; secondly, by reasonably designing the air circulation path, the air is fully utilized to take away the heat. Increasing the heat dissipation area and the utilization rate of air improves the heat dissipation efficiency of the windings.

[0005] To achieve the above object, the present invention provides the following technical solutions: A box-type transformer high and low voltage winding ventilation cooling structure, comprising a transformer box, a transformer three-phase cylinder, an iron core, an iron core upper clamp, an iron core lower clamp and a lower wind shield; The transformer three-phase cylinder is provided in plurality, and each transformer three-phase cylinder is arranged around the iron core; The iron core is arranged in the transformer box through an upper iron core clamp and a lower iron core clamp; The transformer box is also provided with a distribution cabinet baffle, and the transformer box is separated from the transformer three-phase cylinder and the high and low voltage distribution cabinets in the transformer box by the distribution cabinet baffle; The lower wind shield is fixedly arranged in the transformer box, the lower wind shield divides the transformer box into an upper air outlet part and a lower air supply part, and the lower wind shield is sleeved on the outer wall of the transformer three-phase cylinder; The upper air outlet portion of the transformer box is provided with a plurality of air outlets in two upper and lower rows; A plurality of ventilation channels are axially provided in the epoxy potting cylinder of the high-voltage winding of the three-phase cylinder of the transformer.

[0006] As a further description of the above scheme, the core upper clamp includes a fixing plate and a first connecting bolt, two fixing plates are provided, and the two fixing plates are arranged in parallel, and both ends of the fixing plate are fixedly arranged inside the transformer box; the two fixing plates are connected by the first connecting bolt, and when the core is installed, the two fixing plates of the core upper clamp are fixed to the upper part of the core by the first connecting bolt; The structure of the lower core clamp is the same as that of the upper core clamp. The lower core clamp includes a fixing plate and a second connecting bolt. Two fixing plates are provided and the two fixing plates are arranged in parallel. Both ends of the fixing plates are fixed inside the transformer box. The two fixing plates are connected by the second connecting bolts. When the core is installed, the two fixing plates of the lower core clamp are fixed to the lower part of the core by the second connecting bolts.

[0007] As a further description of the above scheme, the lower wind shield is provided with a hole matching the three-phase cylinder of the transformer, and the three-phase cylinder of the transformer is respectively composed of a low-voltage winding epoxy potting cylinder, a low-voltage winding insulation cylinder, a high-voltage winding insulation cylinder, a high-voltage winding epoxy potting cylinder and a high-voltage outer insulation cylinder from the inside to the outside, and the lower part of the high-voltage outer insulation cylinder is fixedly connected to the inner wall of the hole of the lower wind shield; a plurality of through ventilation channels are spaced apart in the high-voltage winding epoxy potting cylinder, and the ventilation channels are arranged along the height direction of the high-voltage winding epoxy potting cylinder, and the high-voltage winding epoxy potting cylinder is provided with a plurality of through ventilation channels. The outer wall and the inner wall of the epoxy potting cylinder are both provided with first protrusions at intervals along the circumferential direction, the first protrusions are arranged along the height direction of the high-voltage winding epoxy potting cylinder, and every two adjacent first protrusions form a first ventilation groove; the inner wall and the outer wall of the low-voltage winding epoxy potting cylinder are both provided with a plurality of second protrusions at intervals along the circumferential direction, the second protrusions are arranged along the height direction of the low-voltage winding epoxy potting cylinder, and every two adjacent second protrusions form a second ventilation groove; the cross-sectional shapes of the second protrusions and the first protrusions are rectangular, sawtooth, trapezoidal, semicircular or parabolic.

[0008] As a further description of the above scheme, the ventilation and cooling structure of the high and low voltage windings of the box-type transformer also includes an upper pressure block and a lower pressure block, wherein a plurality of upper pressure blocks are provided, and each of the upper pressure blocks includes a pressure block body and a rib plate, and a card slot is provided at the bottom of the pressure block body, and the pressure block body is engaged with the top of the low voltage winding insulation cylinder or the high voltage winding insulation cylinder through the card slot; the rib plate is fixedly arranged on the pressure block body by bolts, and the rib plate is fixedly connected to the fixing plate of the clamp on the iron core; There are multiple lower end pressure blocks, each of which includes a pressure block body and a rib plate. A slot is provided on the top of the pressure block body, and the pressure block body is snap-fitted with the top of the low-voltage winding insulation cylinder or the high-voltage winding insulation cylinder through the slot; the rib plate is fixed to the body by bolts, and the rib plate is fixedly connected to the fixing plate of the lower clamp of the iron core.

[0009] As a further description of the above scheme, an insulating wind shield is provided at the bottom of the low-voltage winding insulation cylinder and the high-voltage winding insulation cylinder; a card slot matching the insulating wind shield is provided at the top of the lower end pressure block, and the lower end pressure block is snap-fitted with the insulating wind shield.

[0010] As a further description of the above scheme, the ventilation and cooling structure of the high and low voltage windings of the above box-type transformer also includes an upper shunt wind shield, one end of which is fixedly arranged inside the transformer box, and the other end of the upper shunt wind shield is abutted against the side wall of the fixed plate of the iron core upper clamp, and the upper shunt wind shield is located above the lower wind shield; the plurality of air outlets include an upper air outlet and a lower air outlet, and the upper air outlet and the lower air outlet are symmetrically arranged above and below the upper shunt wind shield, and the bottom height of the lower air outlet is higher than the top height of the three-phase cylinder of the transformer.

[0011] As a further description of the above scheme, when the transformer box is cooled, the cooling air path includes an upper air outlet system and a lower air outlet cooling system, and the lower air outlet system is provided by the lower air supply part through the front half of the gap between the inner side of the insulating cylinder outside the high-voltage winding and the outer side of the epoxy resin potting cylinder of the high-voltage winding, the front half of the gap between the inner side of the epoxy resin potting cylinder of the high-voltage winding and the outer side of the epoxy resin potting cylinder of the low-voltage winding, and the front half of the gap between the inner side of the epoxy resin potting cylinder of the low-voltage winding and the outer surface of the iron core. The air is discharged from the box body through the lower air outlet through the shunting effect of the upper shunt wind shield; the upper air outlet system is composed of the lower air supply part, through the rear half of the gap between the inner side of the insulating cylinder outside the high-voltage winding and the outer side of the high-voltage winding epoxy resin potting cylinder, the rear half of the gap between the inner side of the high-voltage winding epoxy resin potting cylinder and the outer side of the low-voltage winding epoxy resin potting cylinder, and the rear half of the gap between the inner side of the low-voltage winding epoxy resin potting cylinder and the outer surface of the iron core, and is discharged from the box body through the upper air outlet through the shunting effect of the upper shunt wind shield.

[0012] As a further description of the above scheme, four layers of circular grooves are provided in the upper wind shield plate of the insulating tube for fixing with four layers of high-voltage and low-voltage main insulating tubes; the upper wind shield plate of the insulating tube is assembled with four groups of upper pressure blocks; there is a trapezoidal wind shield structure on the inner and outer sides of the upper wind shield plate of the insulating tube.

[0013] Advantages and effects of the present invention: 1. The present invention adopts a new cooling system with epoxy resin potting technology. By increasing the heat dissipation area of ​​epoxy resin and air convection, the heat dissipation efficiency of the windings in each package is improved; secondly, by reasonably designing the air circulation path, the air is fully utilized to take away the heat. The heat dissipation area and air utilization are increased to improve the heat dissipation efficiency of the windings. By changing the shape of the winding potting, the strength of the winding can be increased, and the heat dissipation area can be increased, thereby improving the heat dissipation performance of the transformer. This change helps to suppress the temperature rise of the winding, effectively reduce the operating temperature of the transformer, and improve the reliability and service life of the equipment.

[0014] 2. The inner wall and outer wall of the high-voltage winding epoxy potting cylinder and the low-voltage winding epoxy potting cylinder of the present design are respectively provided with a plurality of first ventilation grooves and second ventilation grooves. This shape increases the heat dissipation area of ​​the high-voltage winding epoxy potting cylinder and the low-voltage winding epoxy potting cylinder, so that the cooling effect is better; at the same time, a plurality of through ventilation channels are spaced apart inside the high-voltage winding epoxy potting cylinder, and cooling air can also be introduced into the high-voltage winding epoxy potting cylinder, so that the cooling effect is better, and the amount of potting material used is also reduced.

[0015] 3. The present invention forms a sealed space by designing an insulating windshield, thereby improving the utilization rate of air and further reducing the temperature rise of the iron core and winding. This measure helps to optimize the heat dissipation structure and improve the working efficiency and stability of the transformer.

[0016] 4. The wind shield at the upper end of the insulating cylinder of this design implements a change operation on the fluid domain of the air in the box. When the wind flows through the upper end of the winding potting cylinder, the wind flow speed is increased, the heat dissipation efficiency is enhanced, and the problem of local overheating of the winding potting cylinder is effectively resolved. This improvement measure can optimize the air flow state in the box, allowing more heat to be evacuated in time with the faster wind flow, preventing the local heat accumulation of the winding potting cylinder and causing overheating, and providing strong support for the smooth operation of the equipment. It makes the heat exchange process in the box more efficient, and the wind can take away the heat generated by the winding potting cylinder more quickly, ensuring that the equipment will not fail or perform poorly due to local overheating during operation, ensuring the stability and reliability of the entire system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the ventilation and cooling structure of the high and low voltage windings of the box-type transformer according to an embodiment of the present invention; Figure 2 An exploded view of the ventilation and cooling structure of the high and low voltage windings of the box-type transformer according to an embodiment of the present invention; Figure 3 It is a cross-sectional schematic diagram of a high voltage winding epoxy resin potting cylinder according to an embodiment of the present invention; Figure 4 It is a cross-sectional schematic diagram of a high voltage winding epoxy resin potting cylinder according to an embodiment of the present invention; Figure 5 For the embodiment of the present invention Figure 3 A magnified view of part A; Figure 6 is a cross-sectional view of a three-phase transformer cylinder according to an embodiment of the present invention; Figure 7 It is an assembly diagram of a three-phase cylinder and an upper end pressing block of a transformer according to an embodiment of the present invention; Figure 8 It is an assembly diagram of a three-phase cylinder and a lower end pressing block of a transformer according to an embodiment of the present invention; Fig. 9 It is an assembly diagram of a transformer three-phase cylinder, an upper end pressing block and a lower end pressing block according to an embodiment of the present invention; Fig.10 This is a schematic diagram of the upper end pressing block structure of an embodiment of the present invention; Fig.11 It is an assembly diagram of the upper end pressing block of an embodiment of the present invention; Fig.12 This is a schematic diagram of the installation structure of the core upper clamping member according to an embodiment of the present invention; Fig.13 It is a partial enlarged view of the core upper clamp of an embodiment of the present invention; Fig.14 It is a structural schematic diagram of an insulating wind shield of a ventilation and cooling structure for high and low voltage windings of a box-type transformer according to an embodiment of the present invention; Fig.15 This is a schematic diagram of installing an insulating windshield according to an embodiment of the present invention; Fig.16 A cross-sectional view of a windshield plate at the upper end of an insulating cylinder according to an embodiment of the present invention; Fig.17 The figure is a schematic diagram of the cooling air path of the ventilation and cooling structure of the high and low voltage windings of the box-type transformer according to an embodiment of the present invention.

[0018] In the accompanying drawings, the components represented by the reference numerals are listed as follows: 1. Iron core upper clamp; 2. Iron core lower clamp; 3. Upper shunt windshield; 4. Lower windshield; 5. Insulation windshield; 6. Upper end pressure block; 7. Lower end pressure block; 8. Rib; 9. Iron core; 10. High voltage winding outer insulation cylinder; 11. High voltage winding insulation cylinder; 12. Low voltage winding epoxy resin potting cylinder; 13. High voltage winding epoxy resin potting cylinder; 14. Windshield fixing piece; 15. Nut; 16. Gasket ; 17. First connecting bolt; 18. Second connecting bolt; 19. Transformer box; 20. Upper air outlet; 21. Lower air outlet; 22. Axial heat dissipation air path A; 23. Axial heat dissipation air path B; 24. Axial heat dissipation air path C; 25. Ventilation channel; 26. Second ventilation slot; 28. First ventilation slot; 29. ​​Air; 30. Distribution cabinet baffle; 31. High and low voltage distribution cabinet; 32. Wind shield at the upper end of the insulating tube. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention.

[0020] like Figure 1-Figure 16 As shown, a box-type transformer high and low voltage winding ventilation cooling structure includes a transformer box 19, a transformer three-phase cylinder, an iron core, an iron core upper clamp 1, an iron core lower clamp 2, and a lower wind shield 4. There are multiple three-phase transformer tubes, and each three-phase transformer tube is arranged around the iron core; The iron core 9 is arranged in the transformer box 19 through the iron core upper clamp 1 and the iron core lower clamp 2; The transformer box 19 is also provided with a distribution cabinet baffle 30, and the transformer box 19 is separated from the transformer three-phase cylinder and the high and low voltage distribution cabinets in the transformer box 19 by the distribution cabinet baffle 30; The lower windshield 4 is fixedly arranged in the transformer box 19, wherein the lower windshield 4 divides the transformer box 19 into an upper air outlet and a lower air supply, and the lower windshield 4 is sleeved on the outer wall of the transformer three-phase barrel; wherein the upper air supply of the transformer box 19 is provided with a plurality of air outlets; wherein the high-voltage winding epoxy potting cylinder of the transformer three-phase barrel is provided with a plurality of ventilation channels along the axial direction. The high-voltage and low-voltage winding potting cooling structure of the transformer designed in this invention is designed with a special air duct and exhaust system, which can make the air flow quickly through the heat dissipation surface through forced convection, thereby improving the heat dissipation efficiency. Compared with the naturally air-cooled transformer, the temperature of the transformer can be effectively reduced in a shorter time; at the same time, the design is suitable for various environmental conditions, especially in high temperature or high altitude areas, and its heat dissipation effect can be kept stable. It not only relies on natural wind, but also increases the adaptability to environmental conditions through the fan system; in addition, the design adjusts the heat dissipation efficiency by controlling the running speed of the fan, thereby achieving more flexible temperature control. This design provides better response and regulation capabilities when dealing with transformer operating requirements under different load and environmental conditions.

[0021] The core upper clamp 1 of the embodiment of the present invention includes a fixing plate and a first connecting bolt 17, wherein two fixing plates are provided, and the two fixing plates are arranged in parallel, and both ends of the fixing plates are fixedly arranged inside the transformer box 19; the two fixing plates are connected by the first connecting bolt 17, and when the core is installed, the two fixing plates of the core upper clamp 1 are fixed to the upper part of the core 9 by the first connecting bolt 17; The structure of the lower core clamp 2 is the same as that of the upper core clamp 1. The lower core clamp 2 includes a fixing plate and a second connecting bolt 18. Two fixing plates are provided, and the two fixing plates are arranged in parallel. Both ends of the fixing plates are fixed inside the transformer box 19. The two fixing plates are connected by the second connecting bolts 18. When the core 9 is installed, the two fixing plates of the lower core clamp 2 are fixed to the lower part of the core 9 by the second connecting bolts 18.

[0022] The lower windshield plate 4 of the embodiment of the present invention is provided with a hole matching the three-phase tube of the transformer, wherein the three-phase tube of the transformer is respectively a low-voltage winding epoxy potting tube 12, a low-voltage winding insulation tube, a high-voltage winding insulation tube 11, a high-voltage winding epoxy potting tube 13 and a high-voltage outer insulation tube 10 from the inside to the outside, wherein the lower part of the high-voltage outer insulation tube 10 is fixedly connected to the inner wall of the hole of the lower windshield plate 4; wherein a plurality of through ventilation channels 25 are spaced apart in the high-voltage winding epoxy potting tube 13, wherein the ventilation channels 25 are arranged along the height direction of the high-voltage winding epoxy potting tube 13, and the ventilation channels 25 are arranged in three layers along the radial direction of the high-voltage winding epoxy potting tube 13, wherein the cross-section of the ventilation channels 25 is a sawtooth section. surface, wherein the sawtooth cross-section includes crests and troughs alternately arranged in the circumferential direction of the ventilation channel 25; first protrusions are arranged at intervals along the circumferential direction on the outer wall and the inner wall of the high-voltage winding epoxy potting cylinder 13, wherein the first protrusions are arranged along the height direction of the high-voltage winding epoxy potting cylinder 13, and every two adjacent first protrusions form a first ventilation groove 28; wherein the inner wall and the outer wall of the low-voltage winding epoxy potting cylinder 12 are provided with a plurality of second protrusions at intervals along the circumferential direction, wherein the second protrusions are arranged along the height direction of the low-voltage winding epoxy potting cylinder 12, and every two adjacent second protrusions form a second ventilation groove 26; the cross-sectional shape of the second protrusion and the first protrusion is rectangular, sawtooth, trapezoidal, semicircular or parabolic. The inner wall and outer wall of the high-voltage winding epoxy potting tube 13 and the low-voltage winding epoxy potting tube 12 of the present design are respectively provided with a plurality of first ventilation grooves 28 and second ventilation grooves 26. This shape increases the heat dissipation area of ​​the high-voltage winding epoxy potting tube 13 and the low-voltage winding epoxy potting tube 12, so that the cooling effect is better; at the same time, a plurality of through ventilation channels are spaced apart in the high-voltage winding epoxy potting tube 13, and cooling air can be introduced into the high-voltage winding epoxy potting tube 13, so that the cooling effect is better, and the amount of potting material used is also reduced; at the same time, the serrated cross-section of the ventilation channel and the ventilation channel 25 are provided with a three-layer design along the radial direction of the high-voltage winding epoxy potting tube 13, which further enhances the cooling effect.

[0023] The box-type transformer high and low voltage winding ventilation cooling structure of the embodiment of the present invention comprises an upper end pressing block 6 and a lower end pressing block 7, wherein a plurality of upper end pressing blocks 6 are provided, and each upper end pressing block 6 comprises a pressing block body and a rib plate 8, wherein a card slot is provided at the bottom of the pressing block body, and the pressing block body is engaged with the top of the low voltage winding insulation cylinder or the high voltage winding insulation cylinder 11 through the card slot; wherein the rib plate 8 is fixedly arranged on the pressing block body by bolts, and the rib plate 8 is fixedly connected to the fixing plate of the core upper clamp 1; There are multiple lower end pressing blocks 7, each of which includes a pressing block body and a rib plate 8, wherein a slot is provided on the top of the pressing block body, and the pressing block body is snap-fitted with the top of the low-voltage winding insulation cylinder or the high-voltage winding insulation cylinder 11 through the slot; wherein the rib plate 8 is fixedly arranged on the body by bolts, and the rib plate 8 is fixedly connected to the fixing plate of the lower core clamp 2. This design can improve the strength of the overall transformer three-phase cylinder through the upper end pressing block 6 and the lower end pressing block 7. These structural improvement measures help reduce the vibration or deformation problems that the transformer may encounter during use, and enhance the durability and safety of the equipment.

[0024] The bottom of the low-voltage winding insulation cylinder and the high-voltage winding insulation cylinder 11 of the embodiment of the present invention are provided with an insulating windshield 5; wherein the top of the lower end pressing block 7 is provided with a slot matching the insulating windshield 5, and the lower end pressing block 7 is engaged with the insulating windshield 5. This embodiment forms a sealed space and a directional radial cooling air flow path by designing the insulating windshield 5, the upper shunt windshield 3 and the lower windshield 4, thereby avoiding the characteristics of chaotic, slow and mutual interference of air flow in the box body 19 of the traditional box-type transformer, improving the utilization rate of the air 29 and achieving a better reduction effect.

[0025] The top of the low-voltage winding insulation cylinder and the high-voltage winding insulation cylinder 11 of the embodiment of the present invention are provided with an insulation cylinder upper end windshield 32; wherein the bottom of the upper end pressure block 6 is provided with a card slot matching the insulation cylinder upper end windshield 32, and the upper end pressure block 6 is engaged with the insulation cylinder upper end windshield 32. In order to effectively solve the problem of overheating of the upper end of the winding potting cylinder, we can focus on increasing the speed of air flowing through its upper end to enhance the heat dissipation efficiency. When the air flow rate is accelerated, the heat generated by the upper end of the winding potting cylinder can be taken away more quickly, just like a turbulent water flow can take away floating objects faster. In this way, the overheating condition of the upper end can be significantly improved, ensuring the stable operation of the equipment, reducing the risk of failure due to overheating, and extending the service life of the equipment.

[0026] The ventilation and cooling structure of the high and low voltage windings of the box-type transformer in the embodiment of the present invention also includes an upper shunt wind shield, wherein one end of the upper shunt wind shield is fixedly arranged inside the transformer box 19 through a wind shield fixing member 14, and the other end of the upper shunt wind shield is abutted against the side wall of the fixing plate of the iron core upper clamp, and the upper shunt wind shield is located above the lower wind shield; a plurality of air outlets include an upper air outlet 20 and a lower air outlet 21, wherein the upper air outlet 20 and the lower air outlet 21 are symmetrically arranged above and below the upper shunt wind shield 3, and the bottom height of the lower air outlet 21 is higher than the top height of the three-phase cylinder of the transformer.

[0027] When the transformer box 19 of the embodiment of the present invention is cooled, the path of the cooling air is: the lower air supply part - the ventilation channel in the high-voltage winding epoxy potting tube 12 and the axial hole between the transformer three-phase tube and the iron core 9 - the upper air outlet 20 of the upper shunt windshield 3 and the lower air outlet 21 of the upper shunt windshield 3. This design takes into account the low heat dissipation efficiency of the wind power transformer itself and takes measures to add an exhaust fan. This measure can increase the wind speed and air utilization rate, effectively reduce the temperature rise of the iron core 9 and the winding, and improve the overall heat dissipation effect. At the same time, by designing the insulating windshield 5, a sealed space is formed, the air utilization rate is improved, and the temperature rise of the iron core 9 and the winding is further reduced. This measure helps to optimize the heat dissipation structure and improve the working efficiency and stability of the transformer. In addition, the upper diverter wind shield 3, the lower wind shield 4 and the insulating wind shield 5 are introduced to avoid the shortcomings of chaotic, slow and mutual interference of air flow in the traditional box-type transformer box 19. These designs improve the flow direction of the air domain in the transformer box 19, so that the air 29 forms a closed loop, improves the utilization rate of the air 29, and continuously and effectively reduces the temperature.

[0028] Specifically, Figure 16-17 As shown, the lower wind shield 4 is provided with three holes matching the three-phase cylinder of the transformer, the three-phase cylinder of the transformer is fixedly connected to the inner wall of the hole of the lower wind shield 4, and cooperates with the upper shunt wind shield 3 and the insulating wind shield 5 to form three heat dissipation air paths, and the paths of the ventilation cooling air of each heat dissipation air path are: the lower air supply part - the ventilation channel in the high-voltage winding epoxy potting cylinder 12 and the axial hole between the three-phase cylinder of the transformer and the iron core 9 - the upper air outlet 20 of the upper shunt wind shield 3 and the lower air outlet 21 of the upper shunt wind shield 3.

[0029] The upper wind shield 32 of the insulating tube of the present invention is provided with four layers of circular grooves to fix the four layers of high-voltage and low-voltage main insulating tubes 11; the upper wind shield 32 of the insulating tube is assembled with four groups of upper pressure blocks 6; the inner and outer sides of the upper wind shield 32 of the insulating tube are provided with a trapezoidal wind shield structure. The specific upper wind shield 32 of the insulating tube can effectively prevent the wind from the air inlet from flowing out of the box body from the gap between the four layers of main insulation 11 from the top, thereby improving the utilization rate of the wind in the box body. Trapezoidal wind shield structures are respectively provided on both sides of the upper wind shield 32 of the insulating tube. The inner side of the trapezoidal wind shield structure is 30 mm wide, which reduces the gap between the main insulating tube 11 and the upper end of the outer side of the low-voltage winding epoxy resin potting tube 12. When the wind passes through the upper end part, the flow rate of the wind can be increased, and the heat dissipation effect of this part can be improved. The fluid domain of the air in the transformer box 19 is changed, and the wind flow rate is increased when the wind flows through the upper end of the winding potting cylinder, so as to improve the heat dissipation efficiency, thereby effectively solving the problem of local overheating of the winding potting cylinder. Such improvement measures can optimize the air flow conditions in the transformer box 19, so that more heat can be taken away in time with the faster wind flow, avoiding the overheating caused by local heat accumulation in the winding potting cylinder, and providing a strong guarantee for the stable operation of the equipment.

[0030] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A box-type transformer high and low voltage winding ventilation and cooling structure, characterized in that: It comprises a transformer box (19), a transformer three-phase cylinder, an iron core (9), an upper iron core clamp (1), a lower iron core clamp (2) and a lower windshield (4); A plurality of three-phase transformer cylinders are provided, and each three-phase transformer cylinder is disposed around an iron core (9); The iron core (9) is arranged in a transformer box (19) via an upper iron core clamp (1) and a lower iron core clamp (2); The transformer box (19) is further provided with a distribution cabinet baffle (30), and the transformer box (19) is used to separate the transformer three-phase cylinder and the high and low voltage distribution cabinets in the transformer box (19) through the distribution cabinet baffle (30); The lower wind shield (4) is fixedly arranged in the transformer box (19), the lower wind shield (4) divides the transformer box (19) into an upper air outlet portion and a lower air supply portion, and the lower wind shield (4) is sleeved on the outer wall of the transformer three-phase cylinder; The upper air outlet portion of the transformer box (19) is provided with a plurality of air outlets in two upper and lower rows; A plurality of ventilation channels are provided in the high-voltage winding epoxy potting cylinder (13) of the three-phase cylinder of the transformer along the axial direction.

2. The box-type transformer high and low voltage winding ventilation and cooling structure according to claim 1 is characterized in that: The core upper clamp (1) comprises a fixing plate and a first connecting bolt (17), two fixing plates are provided, and the two fixing plates are arranged in parallel, and both ends of the fixing plates are fixedly arranged inside the transformer box (19); the two fixing plates are connected by the first connecting bolt (17), and when the core is installed, the two fixing plates of the core upper clamp (1) are fixed to the upper part of the core (9) by the first connecting bolt (17); The iron core lower clamp (2) has the same structure as the iron core upper clamp (1), and comprises a fixing plate and a second connecting bolt (18). Two fixing plates are provided, and the two fixing plates are arranged in parallel. Both ends of the fixing plates are fixedly arranged inside the transformer box (19); the two fixing plates are connected by the second connecting bolt (18). When the iron core (9) is installed, the two fixing plates of the iron core lower clamp (2) are fixed to the lower part of the iron core (9) by the second connecting bolt (18).

3. The box-type transformer high and low voltage winding ventilation and cooling structure according to claim 2 is characterized in that: The lower windshield (4) is provided with a hole matching the three-phase tube of the transformer. The three-phase tube of the transformer comprises, from the inside to the outside, a low-voltage winding epoxy potting tube (12), a low-voltage winding insulation tube, a high-voltage winding insulation tube (11), a high-voltage winding epoxy potting tube (13) and a high-voltage outer insulation tube (10). The lower part of the high-voltage outer insulation tube (10) is fixedly connected to the inner wall of the hole of the lower windshield (4). A plurality of through ventilation channels (25) are arranged at intervals in the high-voltage winding epoxy potting tube (13). The ventilation channels (25) are arranged along the height direction of the high-voltage winding epoxy potting tube (13). The outer wall and the inner wall of the high-voltage winding epoxy potting cylinder (13) are both provided with first protrusions at intervals along the circumferential direction, the first protrusions are provided along the height direction of the high-voltage winding epoxy potting cylinder (13), and every two adjacent first protrusions form a first ventilation groove (28); the inner wall and the outer wall of the low-voltage winding epoxy potting cylinder (12) are both provided with a plurality of second protrusions at intervals along the circumferential direction, the second protrusions are provided along the height direction of the low-voltage winding epoxy potting cylinder (12), and every two adjacent second protrusions form a second ventilation groove; the cross-sectional shapes of the second protrusions and the first protrusions are rectangular, sawtooth, trapezoidal, semicircular or parabolic.

4. The box-type transformer high and low voltage winding ventilation and cooling structure according to claim 3, comprising: It also includes an upper pressure block (6) and a lower pressure block (7), wherein a plurality of upper pressure blocks (6) are provided, each of the upper pressure blocks (6) includes a pressure block body and a rib plate (8), a slot is provided at the bottom of the pressure block body, and the pressure block body is engaged with the top of the low-voltage winding insulation cylinder or the high-voltage winding insulation cylinder (11) through the slot; the rib plate (8) is fixedly arranged on the pressure block body by bolts, and the rib plate (8) is fixedly connected to the fixing plate of the core upper clamp (1); A plurality of lower end pressing blocks (7) are provided, each of which comprises a pressing block body and a rib plate (8). A slot is provided on the top of the pressing block body, and the pressing block body is snap-fitted with the top of the low-voltage winding insulation cylinder or the high-voltage winding insulation cylinder (11) through the slot. The rib plate (8) is fixedly arranged on the body by bolts, and the rib plate (8) is fixedly connected to the fixing plate of the lower core clamp (2).

5. The box-type transformer high and low voltage winding ventilation and cooling structure according to claim 4 is characterized in that: An insulating windshield (5) is provided at the bottom of the low-voltage winding insulating cylinder and the high-voltage winding insulating cylinder (11); a slot matching the insulating windshield (5) is provided at the top of the lower end pressing block (7); the lower end pressing block (7) is snap-fitted with the insulating windshield (5).

6. The box-type transformer high and low voltage winding ventilation and cooling structure according to claim 4 is characterized in that: It also includes an upper shunt wind shield (3), one end of which is fixedly arranged inside the transformer box (19), and the other end of which is in contact with the side wall of the fixing plate of the core upper clamp (1), and the upper shunt wind shield (3) is located above the lower wind shield 4; the plurality of air outlets include an upper air outlet (20) and a lower air outlet (21), and the upper air outlet (20) and the lower air outlet (21) are symmetrically arranged above and below the upper shunt wind shield (3), and the bottom height of the lower air outlet (21) is higher than the top height of the transformer three-phase barrel.

7. The box-type transformer high and low voltage winding ventilation and cooling structure according to claim 4 is characterized in that: When the transformer box (19) is cooled, the cooling air flows in the following paths: the lower air supply portion - between the inner side of the high-voltage winding outer insulating cylinder (10) and the high-voltage winding epoxy resin potting cylinder (13), between the inner side of the high-voltage winding epoxy resin potting cylinder (13) and the low-voltage winding epoxy resin potting cylinder (12), and between the low-voltage winding epoxy resin potting cylinder (12) and the outer surface of the iron core (9) - and is discharged from the transformer box (19) through the lower air outlet (21) and the upper air outlet (21) respectively under the shunting effect of the upper shunting windshield (3).

8. The box-type transformer high and low voltage winding ventilation and cooling structure according to claim 4 is characterized in that: It also includes an upper windshield (32) at the insulating cylinder end, wherein the upper windshield (32) at the insulating cylinder end is provided with four layers of circular grooves for fixing the four layers of high-voltage and low-voltage main insulating cylinders (11); the upper windshield (32) at the insulating cylinder end is assembled with four groups of upper end pressing blocks (6); and a trapezoidal windshield structure is provided inside and outside the upper windshield (32) at the insulating cylinder end.

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