A high-voltage, high-current fiberglass dry bushing

Abstract

This utility model relates to a high-voltage, high-current fiberglass dry bushing, comprising a core and a lower flange fixed to the outer wall of the core. An upper flange, fitted onto the core, is fixed to the top of the lower flange via a cylinder. An outer insulating porcelain sleeve, fitted onto the core, is fixed to the top of the upper flange. A voltage equalization ball, abutting against the outer wall of the core, is fitted and sealed to the top of the outer insulating porcelain sleeve. An equipotential structure with spring-loaded contacts abutting against the outer wall of the core is provided inside the voltage equalization ball. A first terminal block is fixedly installed on the top of the core, and a second terminal block is fixed to the bottom of the core via a cover plate. A voltage equalization cover, fixed to the outer wall of the cover plate, is fitted onto the second terminal block. Sealant is filled between the cylinder and the core, and electrical grease is filled between the outer insulating porcelain sleeve and the core. This utility model not only facilitates the entry of current from external high-voltage lines into the transformer for voltage ratio adjustment but also increases the current carrying capacity of the device during use.

Description

Technical Field

[0001] This utility model relates to the field of power transmission equipment technology, specifically to a high-voltage, high-current fiberglass dry bushing. Background Technology

[0002] With the rapid development of power systems, transformers, as core equipment for power conversion and transmission, face increasingly diverse demands for bushing technology. Traditional fiberglass dry bushings, due to their advantages such as light weight, high mechanical strength, and resistance to pollution, are widely used in distribution transformers with voltage levels of 40.5kV and below, undertaking the tasks of conduction and insulation for low-voltage, high-current (typically ≤6000A). However, in scenarios such as ultra-high-voltage transmission, large industrial power grids, or new energy grid integration, transformers must simultaneously meet the stringent operating conditions of high voltage levels (≥72.5kV) and ultra-high currents (>4000A), which places demands on bushing design.

[0003] In existing technologies, there is a certain contradiction between voltage and current. High-voltage bushings can withstand electric field stress by optimizing the insulation structure (such as increasing creepage distance and using composite insulation materials), but traditional designs often sacrifice the current carrying capacity, resulting in limited current carrying capacity. For example, the maximum current of a 72.5kV bushing is usually no more than 4000A, which is difficult to meet the high power transmission requirements of large transformers. Utility Model Content

[0004] This utility model addresses the shortcomings of existing technologies by providing a high-voltage, high-current fiberglass dry bushing that not only facilitates the entry of current from external high-voltage lines into the transformer and adjusts the voltage ratio, but also increases the current carrying capacity of the device during use.

[0005] This utility model is achieved through the following technical solution: a high-voltage, high-current fiberglass dry bushing is provided, comprising a core and a lower flange fixed to the outer wall of the core. An upper flange, fitted onto the core, is fixed to the top of the lower flange via a cylinder. An outer insulating porcelain sleeve, fitted onto the core, is fixed to the top of the upper flange. A voltage equalization ball, abutting against the outer wall of the core, is fitted and sealed to the top of the outer insulating porcelain sleeve. An equipotential structure with spring contacts abutting against the outer wall of the core is provided inside the voltage equalization ball. A first terminal block is fixedly installed on the top of the core. A second terminal block is fixed to the bottom of the core via a cover plate. A voltage equalization cover, fixed to the outer wall of the cover plate, is fitted onto the second terminal block. Sealant is filled between the cylinder and the core, and electrical grease is filled between the outer insulating porcelain sleeve and the core.

[0006] In use, this utility model comprises a core and a lower flange fixed to the outer wall of the core. An upper flange, fitted onto the core, is fixed to the top of the lower flange via a cylinder. An outer insulating porcelain sleeve, fitted onto the core, is fixed to the top of the upper flange. A voltage equalization ball, abutting against the outer wall of the core, is fitted and sealed to the top of the outer insulating porcelain sleeve. An equipotential structure with spring contacts abutting against the outer wall of the core is provided inside the voltage equalization ball. A first terminal block is fixedly installed on the top of the core, and a second terminal block is fixed to the bottom of the core via a cover plate. A voltage equalization cover, fixed to the outer wall of the cover plate, is fitted onto the second terminal block. Sealant is filled between the cylinder and the core, and electrical grease is filled between the outer insulating porcelain sleeve and the core. During use, the device requires… First, place the device inside the transformer, immersing it in the transformer oil. Secure the lower flange of the device to the transformer riser using the first fastening bolt. Then, connect the transformer leads to the second terminal block in the equalizing enclosure of the device using the second fastening bolt. Next, connect the external high-voltage line to the first terminal block inside the device using the third fastening bolt. Then, have the operator power on the device, allowing current to flow from the external high-voltage line through the first terminal block into the device, and then through the second terminal block and leads into the transformer. This adjusts the voltage ratio, reducing the high voltage to a lower voltage. This not only facilitates the flow of current from the external high-voltage line into the transformer and adjusts the voltage ratio, but also increases the current carrying capacity of the device during operation.

[0007] Preferably, the core includes a copper core tube and glass fibers wrapped around the outer wall of the copper core tube with glass glue. The top of the glass fibers is attached to the bottom of the equalizing ball, and the bottom of the glass fibers is attached to the top of the cover plate. The cover plate is fitted onto the outer wall of the copper core tube. The bottom of the copper core tube has an oil inlet hole that communicates with the inside of the copper core tube. The outer wall of the copper core tube has an exhaust hole located above the equalizing ball and communicating with the inside of the copper core tube. A venting bolt is tightly fastened inside the exhaust hole. The core consists of a copper core tube and glass fiber wrapped around the outer wall of the copper core tube with glass glue. The top of the glass fiber is attached to the bottom of the equalizing ball, and the bottom of the glass fiber is attached to the top of the cover plate. The cover plate is fitted onto the outer wall of the copper core tube. An oil inlet hole communicating with the inside of the copper core tube is opened at the bottom of the copper core tube. An exhaust hole located above the equalizing ball and communicating with the inside of the copper core tube is opened on the outer wall of the copper core tube. A venting bolt is tightly tightened in the exhaust hole. When the device is in use, the venting bolt is unscrewed from the exhaust hole by rotating it. This allows the oil in the transformer to enter the copper core tube through the oil inlet hole during the process of immersing the device in the transformer oil, thereby filling the internal space of the copper core tube. Afterwards, the venting bolt is screwed back into the exhaust hole. This can improve the current carrying capacity of the device during use.

[0008] Preferably, the inner wall of the lower flange has a circumferentially circumferentially formed an annular groove located within the cylinder, the annular groove extending vertically upwards. Glass fiber is wound around the outer wall of the copper core tube with protrusions that match the annular groove. The lower flange is fixed to the outer wall of the core body via the protrusions and the annular groove. By forming a circumferentially circumferentially formed an annular groove within the cylinder on the inner wall of the lower flange, the annular groove extending vertically upwards, and the glass fiber wound around the outer wall of the copper core tube with protrusions that match the annular groove, the lower flange is fixed to the outer wall of the core body via the protrusions and the annular groove. The use of the annular groove and protrusions improves the stability between the lower flange and the core body during use.

[0009] Preferably, the top of the base of the outer insulating porcelain sleeve is provided with a first bolt that passes vertically downward through the upper flange, and the outer insulating porcelain sleeve and the upper flange are fixedly connected by the first bolt. The use of the first bolt to fix the outer insulating porcelain sleeve and the upper flange together improves the stability between the outer insulating porcelain sleeve and the upper flange during use.

[0010] Preferably, two semi-circular plates are arranged opposite each other on the outer wall of the copper core tube, positioned above the equalizing sphere. The inner walls of both semi-circular plates are fitted against the outer wall of the copper core tube, and the two semi-circular plates are fastened together by a second bolt. The first terminal block is fixedly installed on the top of the core body via the semi-circular plates. By using the semi-circular plates and the second bolt, the stability between the first terminal block and the core body during use is improved, and it is also convenient for operators to connect external high-voltage lines to the first terminal block inside the device using a third fastening bolt.

[0011] Preferably, a threaded hole communicating with the gap between the outer insulating porcelain sleeve and the core is provided on the outer wall of the outer insulating porcelain sleeve. A threaded rod is tightly fitted inside the threaded hole, and a first sealing ring is fitted on the threaded rod and pressed against the outer wall of the outer insulating porcelain sleeve. By providing a threaded hole communicating with the gap between the outer insulating porcelain sleeve and the core on the outer wall of the outer insulating porcelain sleeve, and by providing a threaded rod tightly fitted inside the threaded hole and a first sealing ring fitted on the threaded rod and pressed against the outer wall of the outer insulating porcelain sleeve, the use of the threaded hole, the threaded rod, and the first sealing ring not only facilitates the filling of electrical paste into the gap between the outer insulating porcelain sleeve and the core by the operator, but also ensures that the electrical paste will not leak out from the gap between the outer insulating porcelain sleeve and the core through the threaded hole during use.

[0012] Preferably, a second sealing ring is provided at the bottom of the annular groove, pressing against the bottom of the protrusion, and a third sealing ring is provided at the top of the upper flange, pressing against the base of the outer insulating porcelain sleeve. By providing a second sealing ring at the bottom of the annular groove, a third sealing ring at the top of the upper flange, and a fourth sealing ring attached to the top of the fiberglass tube to abut against the outer wall of the copper core tube, and the fourth sealing ring being fixedly connected to the equalizing ball, the second and third sealing rings prevent transformer oil from entering the device through the gap between the flange and the core.

[0013] Preferably, a measuring hole communicating with the cylinder and the core is provided on the outer wall of the cylinder. By providing a measuring hole communicating with the cylinder and the core on the outer wall of the cylinder, it is convenient for operators to conduct electrical experiments on the device.

[0014] Preferably, the outer wall of the cover plate is provided with a threaded groove, and the inner wall of the pressure equalizing hood is provided with a thread that matches the threaded groove. The cover plate and the pressure equalizing hood are fixed together by the thread fastening within the threaded groove. By providing a threaded groove on the outer wall of the cover plate and a thread on the inner wall of the pressure equalizing hood that matches the threaded groove, and by fixing the cover plate and the pressure equalizing hood together by the thread fastening within the threaded groove, the thread and threaded groove facilitate the installation and fixing of the pressure equalizing hood and the cover plate.

[0015] Preferably, a fourth sealing ring is fitted onto the top of the glass fiber and abuts against the outer wall of the copper core tube. The fourth sealing ring is fixedly connected to the equalizing ball. By fitting the fourth sealing ring onto the top of the glass fiber and abutting against the outer wall of the copper core tube, and fixing the fourth sealing ring to the equalizing ball, transformer oil can be prevented from entering the device through the gap between the core and the equalizing ball.

[0016] The beneficial effects of this utility model are as follows: By setting a core and a lower flange fixed to the outer wall of the core, an upper flange sleeved on the core is fixed to the top of the lower flange via a cylinder, and an outer insulating porcelain sleeve sleeved on the core is fixed to the top of the upper flange. A pressure equalizing ball abutting against the outer wall of the core is fitted and sealed to the top of the outer insulating porcelain sleeve. An equipotential structure with spring contacts abutting against the outer wall of the core is provided inside the pressure equalizing ball. A first terminal block is fixedly installed on the top of the core, and a second terminal block is fixed to the bottom of the core via a cover plate. A pressure equalizing cover fixed to the outer wall of the cover plate is sleeved on the second terminal block. Sealant is filled between the cylinder and the core, and electrical grease is filled between the outer insulating porcelain sleeve and the core. When using the device, it is necessary to... First, place the device inside the transformer, immersing it in the transformer oil. Secure the lower flange of the device to the transformer riser using the first fastening bolt. Then, connect the transformer leads to the second terminal block in the equalizing enclosure of the device using the second fastening bolt. Next, connect the external high-voltage line to the first terminal block inside the device using the third fastening bolt. Then, have the operator power on the device, allowing current to flow from the external high-voltage line through the first terminal block into the device, and then through the second terminal block and leads into the transformer. This adjusts the voltage ratio, reducing the high voltage to a lower voltage. This not only facilitates the flow of current from the external high-voltage line into the transformer and adjusts the voltage ratio, but also increases the current carrying capacity of the device during operation. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model;

[0018] Figure 2 for Figure 1 Perspective view of section A in the middle;

[0019] Figure 3 for Figure 1 Schematic diagram of Part B in the middle section;

[0020] Figure 4 for Figure 3 Structural perspective view;

[0021] Figure 5 This is a perspective view of the structure of this utility model;

[0022] Figure 6 for Figure 5 Schematic diagram of the structure of part C;

[0023] Figure 7 for Figure 5 Schematic diagram of the structure of part D in the middle;

[0024] Figure 8 for Figure 5 Schematic diagram of the structure of part E in the middle;

[0025] As shown in the figure:

[0026] 1. First terminal block; 2. Vent bolt; 3. Outer insulating porcelain sleeve; 4. First bolt; 5. Fiberglass; 6. Equalizing cover; 7. Semi-circular plate; 8. Second bolt; 9. Copper core tube; 10. Equalizing ball; 11. Upper flange; 12. Measuring hole; 13. Lower flange; 14. Vent hole; 15. First sealing ring; 16. Threaded rod; 17. Threaded hole; 18. Electrical paste; 19. Second terminal block; 20. Spring contact finger equipotential structure; 21. Fourth sealing ring; 22. Third sealing ring; 23. Sealant; 24. Annular groove; 25. Second sealing ring; 26. Protrusion; 27. Oil inlet; 28. Cover plate; 29. ​​Threaded groove; 30. Thread; 31. Cylinder. Detailed Implementation

[0027] To clearly illustrate the technical features of this solution, the following detailed implementation method will be used to explain the solution.

[0028] like Figures 1-8 The high-voltage, high-current fiberglass dry bushing of this utility model includes a core and a lower flange 13 fixed to the outer wall of the core. An upper flange 11, which is sleeved on the core, is fixed to the top of the lower flange 13 via a cylinder 31. An outer insulating porcelain sleeve 3, which is sleeved on the core, is fixed to the top of the upper flange 11. A voltage equalization ball 10, which abuts against the outer wall of the core, is fitted and sealed to the top of the outer insulating porcelain sleeve 3. A spring contact equipotential structure 20, which abuts against the outer wall of the core, is provided inside the voltage equalization ball 10. A first terminal block 1 is fixedly installed on the top of the core. A second terminal block 19 is fixed to the bottom of the core via a cover plate 28. A voltage equalization cover 6, which is fixed to the outer wall of the cover plate 28, is sleeved on the second terminal block 19. Sealant 23 is filled between the cylinder 31 and the core. Electrical paste 18 is filled between the outer insulating porcelain sleeve 3 and the core.

[0029] The core includes a copper core tube 9 and glass fiber 5 wrapped with glass glue on the outer wall of the copper core tube 9. The top of the glass fiber 5 is attached to the bottom of the equalizing ball 10, and the bottom of the glass fiber 5 is attached to the top of the cover plate 28. The cover plate 28 is fitted on the outer wall of the copper core tube 9. The bottom of the copper core tube 9 has an oil inlet hole 27 that communicates with the inside of the copper core tube 9. The outer wall of the copper core tube 9 has an exhaust hole 14 located above the equalizing ball 10 and communicating with the inside of the copper core tube 9. A venting bolt 2 is tightly tightened in the exhaust hole 14. When the device is in use, the venting bolt 2 is rotated to unscrew it from the exhaust hole 14. This allows the oil in the transformer to enter the copper core tube 9 through the oil inlet hole 27 during the process of immersing the device in the transformer oil, thereby filling the internal space of the copper core tube 9. Afterwards, the venting bolt 2 is screwed back into the exhaust hole 14. This can improve the current carrying capacity of the device during use. An annular groove 24, located within the cylinder 31, is circumferentially formed on the inner wall of the lower flange 13. The annular groove 24 extends vertically upwards. Glass fiber 5 is wound around the outer wall of the copper core tube 9 with protrusions 26 that match the annular groove 24. The lower flange 13 is fixed to the outer wall of the core body via the protrusions 26 and the annular groove 24. The annular groove 24 and the protrusions 26 enhance the stability between the lower flange 13 and the core body during use. A first bolt 4, extending vertically downwards through the upper flange 11, is provided at the top of the base of the outer insulating porcelain sleeve 3. The outer insulating porcelain sleeve 3 and the upper flange 11 are fixedly connected by the first bolt 4. The first bolt 4 further enhances the stability between the outer insulating porcelain sleeve 3 and the upper flange 11 during use. Two semi-circular plates 7 are arranged opposite each other on the outer wall of the copper core tube 9, located above the equalizing ball 10. The inner walls of the two semi-circular plates 7 are fitted to the outer wall of the copper core tube 9. The two semi-circular plates 7 are fastened together by a second bolt 8. The first terminal block 1 is fixedly installed on the top of the core body through the semi-circular plates 7. The use of the semi-circular plates 7 and the second bolt 8 can not only improve the stability between the first terminal block 1 and the core body when the device is in use, but also make it convenient for the staff to use the third fastening bolt to connect the external high voltage line to the first terminal block 1 inside the device. By providing a threaded hole 17 on the outer wall of the outer insulating porcelain sleeve 3, which communicates with the gap between the outer insulating porcelain sleeve 3 and the core, and a threaded rod 16 tightly fitted inside the threaded hole 17, a first sealing ring 15 is fitted on the threaded rod 16 and pressed against the outer wall of the outer insulating porcelain sleeve 3. The threaded hole 17, the threaded rod 16 and the first sealing ring 15 not only make it convenient for workers to fill the gap between the outer insulating porcelain sleeve 3 and the core with electrical paste 18, but also ensure that the electrical paste 18 will not leak out from the gap between the outer insulating porcelain sleeve 3 and the core through the threaded hole 17 when the device is in use.A second sealing ring 25 is provided at the bottom of the annular groove 24, pressing against the bottom of the protrusion 26; a third sealing ring 22 is provided at the top of the upper flange 11, pressing against the base of the outer insulating porcelain sleeve 3; and a fourth sealing ring 21 is attached to the top of the glass fiber 5, abutting against the outer wall of the copper core tube 9. The fourth sealing ring 21 is fixedly connected to the equalizing ball 10. The second sealing ring 25 and the third sealing ring 22 can prevent transformer oil from entering the device through the gap between the flange and the core. A measuring hole 12 is provided on the outer wall of the cylinder 31, communicating between the cylinder 31 and the core, which facilitates electrical experiments by the operator. A threaded groove 29 is provided on the outer wall of the cover plate 28, and a thread 30 is provided on the inner wall of the equalizing cover 6, which matches the threaded groove 29. The cover plate 28 and the equalizing cover 6 are fixed together by the thread 30 fastened in the threaded groove 29. The thread 30 and the threaded groove 29 facilitate the installation and fixation of the equalizing cover 6 and the cover plate 28. A fourth sealing ring 21 is attached to the top of the glass fiber 5 and abuts against the outer wall of the copper core tube 9. The fourth sealing ring 21 is fixedly connected to the equalizing ball 10. The fourth sealing ring 21 can prevent transformer oil from entering the device through the gap between the core and the equalizing ball 10.

[0030] Combined with appendix Figure 1-8 The method of using this utility model is as follows: First, the vent bolt 2 needs to be rotated to unscrew it from the vent hole 14. Then, the device is placed inside the transformer, immersing it in the oil inside the transformer. The lower flange 13 inside the device is then fixed to the transformer riser using the first fastening bolt. Next, the leads inside the transformer are connected to the second terminal block 19 in the equalizing cover 6 inside the device using the second fastening bolt. Then, the external high-voltage line is connected to the first terminal block 1 inside the device using the third fastening bolt. During the process of immersing the device in the transformer oil, the oil inside the transformer will enter the copper core tube 9 through the oil inlet hole 27, thereby filling the internal space of the copper core tube 9. Then, the vent bolt 2 is screwed back into the vent hole 14. Then, the operator is allowed to power on the device, allowing the current to enter the device from the external high-voltage line through the first terminal block 1, and then through the second terminal block 19 and the leads into the transformer, thereby adjusting the voltage ratio and reducing the high voltage to a low voltage.

[0031] Of course, the above description is not limited to the examples above. Technical features of this utility model not described can be implemented by or using existing technology, and will not be repeated here. The above embodiments and drawings are only used to illustrate the technical solution of this utility model and are not intended to limit this utility model. This utility model has been described in detail with reference to preferred embodiments. Those skilled in the art should understand that any changes, modifications, additions or substitutions made by those skilled in the art within the scope of this utility model do not depart from the spirit of this utility model and should also fall within the protection scope of the claims of this utility model.

Claims

1. A high-voltage, high-current fiberglass dry bushing, characterized in that: The device includes a core and a lower flange (13) fixed to the outer wall of the core. The top of the lower flange is fixed to an upper flange (11) sleeved on the core via a cylinder (31). The top of the upper flange is fixed to an outer insulating porcelain sleeve (3) sleeved on the core. The top of the outer insulating porcelain sleeve is fitted and sealed with an equalizing ball (10) that abuts against the outer wall of the core. The equalizing ball is provided with a spring contact finger equipotential structure (20) that abuts against the outer wall of the core. The top of the core is fixedly installed with a first terminal block (1). The bottom of the core is fixed with a second terminal block (19) via a cover plate (28). The second terminal block is fitted with an equalizing cover (6) fixed to the outer wall of the cover plate. The space between the cylinder and the core is filled with sealant (23). The space between the outer insulating porcelain sleeve and the core is filled with electrical paste (18).

2. The high-voltage, high-current fiberglass dry bushing according to claim 1, characterized in that: The core includes a copper core tube (9) and glass fiber (5) wrapped around the outer wall of the copper core tube with glass glue. The top of the glass fiber is attached to the bottom of the equalizing ball, and the bottom of the glass fiber is attached to the top of the cover plate. The cover plate is fitted on the outer wall of the copper core tube. The bottom of the copper core tube has an oil inlet hole (27) that communicates with the inside of the copper core tube. The outer wall of the copper core tube has an exhaust hole (14) located above the equalizing ball and communicating with the inside of the copper core tube. A venting bolt (2) is tightened in the exhaust hole.

3. The high-voltage, high-current fiberglass dry bushing according to claim 2, characterized in that: The inner wall of the lower flange is provided with an annular groove (24) located inside the cylinder along the circumferential direction. The annular groove extends vertically upward. The glass fiber is wrapped with a protrusion (26) that matches the annular groove on the outer wall of the copper core tube. The lower flange is fixed to the outer wall of the core body by the protrusion and the annular groove.

4. The high-voltage, high-current fiberglass dry bushing according to claim 1, characterized in that: The top of the base of the outer insulating porcelain sleeve is provided with a first bolt (4) that passes vertically downward through the upper flange, and the outer insulating porcelain sleeve and the upper flange are fixedly connected by the first bolt.

5. The high-voltage, high-current fiberglass dry bushing according to claim 2, characterized in that: Two semi-circular plates (7) are arranged opposite each other on the outer wall of the copper core tube, located above the equalizing ball. The inner walls of the two semi-circular plates are fitted to the outer wall of the copper core tube. The two semi-circular plates are fastened together by a second bolt (8). The first terminal block is fixedly installed on the top of the core through the semi-circular plates.

6. The high-voltage, high-current fiberglass dry bushing according to claim 4, characterized in that: A threaded hole (17) communicating with the gap between the outer insulating porcelain sleeve and the core is provided on the outer wall of the outer insulating porcelain sleeve. A threaded rod (16) is tightly fitted in the threaded hole, and a first sealing ring (15) is fitted on the threaded rod and pressed against the outer wall of the outer insulating porcelain sleeve.

7. The high-voltage, high-current fiberglass dry bushing according to claim 3, characterized in that: The bottom of the annular groove is provided with a second sealing ring (25) pressing against the bottom of the protrusion, and the top of the upper flange is provided with a third sealing ring (22) pressing against the base of the outer insulating porcelain sleeve.

8. The high-voltage, high-current fiberglass dry bushing according to claim 4, characterized in that: A measuring hole (12) is provided on the outer wall of the cylinder, which communicates with the cylinder and the core.

9. The high-voltage, high-current fiberglass dry bushing according to claim 4, characterized in that: The outer side wall of the cover plate is provided with a threaded groove (29), and the inner side wall of the pressure equalization cover is provided with a thread (30) that matches the threaded groove. The cover plate and the pressure equalization cover are fixed together by the thread fastened in the threaded groove.

10. The high-voltage, high-current fiberglass dry bushing according to claim 2, characterized in that: The top of the glass fiber is fitted with a fourth sealing ring (21) that abuts against the outer wall of the copper core tube, and the fourth sealing ring is fixedly connected to the pressure equalization ball.

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