Indoor three-phase split voltage transformer with fuse

Abstract

The present invention discloses an indoor three-phase split-type voltage transformer with fuses. The transformer comprises an A-phase insulator and a C-phase insulator symmetrically arranged on either side of a B-phase insulator. The A-phase and C-phase insulators have identical structures, each including a first insulating cylinder disposed on the top outer side, coated with a layer of semi-conductive paint on the inner wall of the first insulating cylinder. A first fuse is disposed within the first insulating cylinder, and a first fuse-terminal primary terminal is disposed above the first insulating cylinder. A second insulating cylinder is disposed on the top of the B-phase insulator, coated with a layer of semi-conductive paint on the inner wall of the second insulating cylinder. A second fuse is disposed within the second insulating cylinder, and a second fuse-terminal primary terminal and a B-phase primary terminal are disposed above the second insulating cylinder. The B-phase primary terminal is connected to the A-phase and C-phase primary terminals, respectively. This structure facilitates product miniaturization, resulting in a compact size, light weight, and comprehensive functionality.

Description

Technical Field

[0001] The present invention relates to the technical field of high-voltage measurement or relay protection of power systems, and in particular to an indoor three-phase split-type voltage transformer with a fuse. Background Art

[0002] Voltage transformer is a device for measuring voltage and electric energy in power system or electrical control system. In order to realize miniaturization of switch cabinet and convenient overhaul and maintenance, ordinary combined voltage transformer has disadvantages such as large size, complex installation and heavy lifting. At the same time, the transformer has a single structure and rough appearance, which makes the switch cabinet produced in conjunction with it also have defects such as large size. In order to realize the functional characteristics of miniaturization of switch cabinet equipment, flexible installation, more fitting and compact structure, and smoother surface structure, it is particularly necessary to design and develop a small-sized and fully-functional voltage transformer. Summary of the Invention

[0003] The purpose of the present invention is to provide a new indoor three-phase split voltage transformer with fuses, which is made of epoxy resin vacuum casting, has a small size, beautiful appearance, flexible installation, easy maintenance, and full functions, so as to change the current situation that the existing combined voltage transformer is heavy and difficult to carry.

[0004] To achieve the above-mentioned objectives, the technical solution of the present application is as follows: an indoor three-phase split-type voltage transformer with fuse, comprising an A-phase insulator, a B-phase insulator and a C-phase insulator, wherein the A-phase insulator and the C-phase insulator are symmetrically arranged on both sides of the B-phase insulator, and the A-phase insulator and the C-phase insulator have the same structure, both comprising a first insulating cylinder arranged on the outer side of the top, a layer of semi-conductive paint being arranged on the inner wall of the first insulating cylinder, a first fuse being arranged in the first insulating cylinder, and a first fuse end primary terminal being arranged on the first insulating cylinder; a second insulating cylinder being arranged on the top of the B-phase insulator, a layer of semi-conductive paint being arranged on the inner wall of the second insulating cylinder, a second fuse being arranged in the second insulating cylinder, and a second fuse end primary terminal and a B-phase primary terminal being arranged on the second insulating cylinder, and the B-phase primary terminal being connected to the A-phase primary terminal and the C-phase primary terminal, respectively.

[0005] In a preferred embodiment, a first arc-shaped shed extending upward is provided on the top of the A-phase insulator and the C-phase insulator, and the first fuse-end primary terminal and the A-phase primary terminal and the C-phase primary terminal are respectively located on both sides of the first arc-shaped shed; grooves are provided on both sides of the lower portion of the A-phase insulator and the C-phase insulator, the upper edge of the groove has a bevel, and a fourth arc-shaped shed extending outward is provided in the groove.

[0006] In a preferred embodiment, a second arc-shaped shed with equal spacing is provided at the lower part of the B-phase insulator; a third arc-shaped shed with equal spacing is provided on the second insulating tube between the second fuse end primary terminal and the B-phase primary terminal.

[0007] In a preferred embodiment, fuse screw sleeves are provided in the ends of the first insulating tube and the second insulating tube. The fuse screw sleeves cooperate with the fuse bolts to seal the corresponding fuses. The fuse bolts are in the shape of a plum blossom.

[0008] In a preferred embodiment, the structure of the A-phase insulator and the C-phase insulator is as follows: the body coil, fuse screw sleeve, primary terminal, and secondary terminal are cast into an integrated structure with epoxy resin; the body coil includes a primary winding, a secondary winding, an iron core, and an insulating skeleton, the secondary winding is wound on the iron core, and an insulating skeleton is provided outside the secondary winding. The insulating skeleton is a cylindrical integrated structure cast with epoxy resin, on which the primary winding is wound, the secondary winding is connected to the secondary terminal on one side of the bottom of the insulator, a secondary protective cover is provided above the secondary terminal, and a grounding bolt is provided on the other side of the bottom of the insulator.

[0009] In a preferred embodiment, the primary winding is connected to the spring in the first insulating cylinder through a screw, and the spring is in contact with the end of the first fuse; the screw is fixed to the first insulating cylinder through a primary insert, and a copper foil is provided on the primary insert, which is in contact with the semi-conductive paint.

[0010] In a preferred embodiment, the B-phase insulator structure is as follows: the B-phase primary wiring terminal and the second fuse-end primary wiring terminal are cast with epoxy resin to form an integrated insulating support structure.

[0011] In a preferred embodiment, the B-phase primary terminal is connected to the spring in the second insulating cylinder through a screw, and the spring is in contact with the end of the second fuse; the screw is fixed to the second insulating cylinder through a primary insert, and a copper foil is provided on the primary insert, which is in contact with the semi-conductive paint.

[0012] In a preferred embodiment, the bottoms of the A-phase insulator and the C-phase insulator are both provided with a first mounting plate, and the bottom of the B-phase insulator is provided with a second mounting plate.

[0013] In a preferred embodiment, the A-phase insulator, the B-phase insulator and the C-phase insulator are arranged in a straight line, and the primary connection line between the B-phase primary terminal and the A-phase primary terminal and the C-phase primary terminal is V-shaped.

[0014] By adopting the above technical solution, the present invention can achieve the following technical effects:

[0015] 1. Small size, light weight, and full functions: The optimized structural design makes the inner surface of the insulating tube more firmly adhered to the semi-conductive paint. It is a new structure different from the traditional shielding mesh. The size is reduced, the overall product occupies less space, and is more conducive to product miniaturization. With small size, light weight and full functions, it is more suitable for use in new voltage transformers supporting switch cabinets;

[0016] 2. Simple operation, easy installation and easy maintenance: When installing and using the product, you only need to install the transformer in the switch cabinet according to the phase sequence. The operation is simple and effectively saves the assembly time of the switch cabinet. The product is also simpler to repair and does not require special maintenance work.

[0017] 3. Uniform electric field and small partial discharge: A layer of semi-conductive paint is provided on the inner wall of the cylindrical cavity of the three-phase insulators A, B, and C. A layer of semi-conductive paint is sprayed on the surface of the mold core during mold assembly. During demoulding, this layer of semi-conductive paint adheres to the inner surface of the insulation cylinder cavity more firmly. During assembly of the finished product, the copper foil contacts the semi-conductive paint to ensure that the semi-conductive paint is connected to the end face of the primary insert. The fuse is placed in the insulation cylinder cavity, which has a better shielding effect, a uniform electric field inside and outside the product, small partial discharge of the product, and safe and reliable product operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is the main view of an indoor three-phase split voltage transformer with fuses;

[0019] Figure 2 It is a side view of the internal structure of the A-phase insulator and the C-phase insulator;

[0020] Figure 3 This is a top view of an indoor three-phase split voltage transformer with fuses;

[0021] Figure 4 It is the side view of the internal structure of the B phase insulator;

[0022] Figure 5 This is the fuse bolt structure diagram;

[0023] Figure 6 Schematic diagram of the position for spraying semi-conductive paint on the mold core.

[0024] Explanation of the numbers in the figure: 1. Iron core; 2. Secondary winding; 3. Primary winding; 4. Body coil; 5. Primary insert; 6. First fuse; 7. Fuse screw; 8. Secondary terminal; 9. Secondary protective cover; 10. Grounding bolt; 11. First mounting plate; 12. Insulation frame; 13. First curved shed; 14. Second curved shed; 15. Phase B primary terminal; 16. Second fuse terminal primary terminal; 17. Fuse bolt; 18. Third curved shed; 19. Second mounting plate; 20. Phase A insulator or Phase C insulator; 21. Phase B insulator; 22. Primary terminal; 23. First fuse terminal primary terminal; 24. Primary connecting wire; 25. Fourth curved shed; 26. Embedded bolt; 27. First insulating tube; 28. Semi-conductive paint; 29. ​​Copper foil. DETAILED DESCRIPTION

[0025] In order to help those skilled in the art better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0026] It should be understood that the terms "upper", "lower", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the 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, and therefore cannot be understood as a limitation on the invention.

[0027] This embodiment provides a compact, fully functional, split-type three-phase, fully fused voltage transformer. This reduces the overall weight of the switchgear, improves its technical capabilities, and avoids the potential safety hazards associated with heavy overhead lifting operations. It also reduces the cost of the switchgear and improves its market competitiveness. The voltage transformer in this application is a next-generation product developed based on the design principles of simplicity, full insulation, safe operation, compact size, easy maintenance, and comprehensive functionality.

[0028] like Figure 1 As shown, the indoor three-phase split-type voltage transformer with fuse includes an A-phase insulator, a B-phase insulator and a C-phase insulator. The A-phase insulator and the C-phase insulator have the same structure. Figure 2As shown, the secondary winding 2 and the primary winding 3 are concentrically wound on an insulating frame 12 through interlayer insulation and then mounted on the iron core 1. After the iron core is assembled, insulated and buffered, they become the body coil 4 in the A-phase insulator and the C-phase insulator, and then fixed in the casting mold. Figure 6 As shown, a layer of semi-conductive paint is sprayed on the surface of the mold core mold. When demoulding, this layer of semi-conductive paint adheres to the inner surface of the insulating tube cavity more firmly and is not easy to be damaged. Then fix the fuse screw sleeve 7 and the primary terminal 23 of the first fuse end; then the primary winding is connected to the spring in the first insulating tube through a screw, and the screw is fixed through a primary insert. A copper foil is provided on the primary insert, and the copper foil is in contact with the semi-conductive paint. It is a new structure different from the traditional shielding mesh shielding, which reduces space and has better shielding effect. The overall product occupies less space and is more conducive to product miniaturization; the fuse screw sleeve 7 is connected to the primary terminal 23 of the first fuse end, and the secondary terminal 8 is connected. The insulation distance is adjusted and epoxy resin is vacuum cast and cured. Finally, the whole is installed on the first mounting plate 11; A and C phases About the left-right axis symmetry of the B phase, a first arc-shaped umbrella skirt 13 protrudes from the middle of the top of the A phase insulator and the C phase insulator, and a first fuse 6 is arranged in the first insulating tube on the outer side of the top and a fourth arc-shaped umbrella skirt 25 is arranged in the groove at the bottom. The transition of the groove slope is in the shape of a cube as a whole, which makes the mutual inductor structure more fitting and more compact. The surface structure of the product is relatively smooth, ensuring uniform insulation and sufficient creepage distance to meet the requirements of high-altitude areas; at the same time, the B phase primary terminal 15 and the second fuse end primary terminal 16 are fixed in the casting mold, and a layer of semi-conductive paint is sprayed on the surface of the mold core mold. When demoulding, this layer of semi-conductive paint is more firmly attached to the inner surface of the insulating tube cavity. It is a new structure different from the traditional shielding mesh shielding, which reduces the space and has a better shielding effect. The overall product occupies less space, such as Figure 4 As shown, the B-phase primary terminal is connected to the spring by a screw, and the screw is fixed by a primary insert. A copper foil is provided on the primary insert. The copper foil is in contact with the semi-conductive paint, which is more conducive to product miniaturization. The second fuse end primary terminal 16 is connected to the fuse screw sleeve 7, and the insulation distance is adjusted. The epoxy resin is vacuum cast and cured, and finally the whole is installed on the second mounting plate 19. Figure 3 As shown, the B-phase primary terminal 15 and the second fuse-end primary terminal 16 are arranged front and back, with a third arc-shaped shed 18 at equal intervals in the middle and a second arc-shaped shed 14 at equal intervals below. This makes the transformer structure more consistent and compact, and the product's surface structure is smoother, ensuring sufficient creepage distance to meet the requirements of high-altitude areas.

[0029] The insulation skeleton 12 of the A-phase insulator and the C-phase insulator is a cylindrical integrated structure cast with epoxy resin to ensure uniform primary and secondary insulation distances;

[0030] In the A-phase insulator and the C-phase insulator, the primary terminal of the first fuse end and the primary terminal are respectively located on both sides of the first arc-shaped shed to increase the creepage distance; and are located at the top to facilitate high-voltage wiring; a first fuse 6 is provided on the outside, and a fuse bolt 17 is provided at the end. Figure 5 As shown, the fuse bolt 17 is an embedded bolt 26 cast with epoxy resin, has sufficient insulation, and has a plum blossom shape, which is convenient for manual installation or replacement of the fuse.

[0031] The B-phase primary terminal 15 and the second fuse-end primary terminal 16 are respectively arranged at the front and rear ends, and the second fuse-end primary terminal 16 is higher than the B-phase primary terminal 15, which is convenient for primary high-voltage wiring; a third arc-shaped shed 18 is provided in the middle, the fuse is located at the upper part of the whole, and a fuse bolt 17 is provided at the end. The fuse bolt 17 is an embedded bolt 26 and is cast with epoxy resin. It has sufficient insulation and is in a plum blossom shape, which is convenient for manual installation or replacement of the fuse; a second arc-shaped shed 14 is provided at equal intervals below, which is set as a whole on the second mounting plate 19 to increase the surface creepage distance.

[0032] During finished product assembly, the end face of primary insert 5 is compressed with hemispherical copper foil 29. The edge of copper foil 29 contacts the semi-conductive paint 28 on the inner wall of first insulating tube 27. This ensures the connection between the semi-conductive paint 28 and the end face of primary insert 5. First fuse 6 is then installed. A grounding bolt 10 is located on one side of the first mounting plate of the A and C phase insulators, located at the bottom of the insulator, to facilitate product grounding safety.

[0033] When in use, first use the voltage transformer's mounting plate to install the voltage transformer on the ring network cabinet chassis in sequence according to the phase sequence distance. The A, B, and C three-phase bodies are arranged in a straight line, and there is a certain electrical gap between the phases. The B phase primary terminal 15 and the A and C phase primary terminal 22 are connected through a primary connecting line 24. Then, according to the three-phase "V" type wiring, the product primary terminals are connected in parallel to the high-voltage side of the line. Finally, the low-voltage side secondary line cable is connected to the secondary terminal, and the anti-theft and anti-secondary protective cover 9 is installed. The installation of the split voltage transformer is completed.

[0034] In the present invention, unless otherwise expressly specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, indirect connection through an intermediate medium; internal communication between two elements, or interaction between two elements. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0035] Relational terms such as first and second, etc., are used solely to distinguish one entity or operation from another entity or operation and do not necessarily require or imply any actual relationship or order between such entities or operations. Furthermore, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0036] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An indoor three-phase split-type voltage transformer with fuse, comprising an A-phase insulator, a B-phase insulator, and a C-phase insulator, characterized in that: The A-phase insulator and the C-phase insulator are symmetrically arranged on both sides of the B-phase insulator. The A-phase insulator and the C-phase insulator have the same structure, both including a first insulating cylinder arranged on the top outer side, a layer of semi-conductive paint provided on the inner wall of the first insulating cylinder, a first fuse arranged in the first insulating cylinder, and a first fuse end primary terminal provided on the first insulating cylinder; a second insulating cylinder is arranged on the top of the B-phase insulator, a layer of semi-conductive paint provided on the inner wall of the second insulating cylinder, a second fuse arranged in the second insulating cylinder, and a second fuse end primary terminal and a B-phase primary terminal provided on the second insulating cylinder, the B-phase primary terminal being connected to the A-phase primary terminal and the C-phase primary terminal, respectively; The structure of the A-phase and C-phase insulators is as follows: the body coil, fuse insert, primary terminal, and secondary terminal are cast into an integrated structure using epoxy resin; the body coil includes a primary winding, a secondary winding, an iron core, and an insulating skeleton, the secondary winding is wound on the iron core, and an insulating skeleton is provided outside the secondary winding. The insulating skeleton is a cylindrical integrated structure cast from epoxy resin, on which the primary winding is wound. The secondary winding is connected to the secondary terminal on one side of the bottom of the insulator, a secondary protective cover is provided above the secondary terminal, and a grounding bolt is provided on the other side of the bottom of the insulator. The primary winding is connected to the spring in the first insulating cylinder through a screw, and the spring is in contact with the end of the first fuse; the screw is fixed to the first insulating cylinder through a primary insert, and a copper foil is provided on the primary insert, and the copper foil is in contact with the semi-conductive paint.

2. The indoor three-phase split voltage transformer with fuse according to claim 1, characterized in that: A first arc-shaped shed extending upward is provided on the top of the A-phase insulator and the C-phase insulator, and the first fuse end primary terminal and the A-phase primary terminal and the C-phase primary terminal are respectively located on both sides of the first arc-shaped shed; grooves are provided on both sides of the lower part of the A-phase insulator and the C-phase insulator, and the upper edge of the groove has a bevel, and a fourth arc-shaped shed extending outward is provided in the groove.

3. The indoor three-phase split voltage transformer with fuse according to claim 1, characterized in that: A second arc-shaped shed with equal spacing is provided at the lower part of the B-phase insulator; a third arc-shaped shed with equal spacing is provided on the second insulating tube between the second fuse end primary terminal and the B-phase primary terminal.

4. The indoor three-phase split voltage transformer with fuse according to claim 1, characterized in that: Fuse screw sleeves are provided in the ends of the first insulating cylinder and the second insulating cylinder. The fuse screw sleeves cooperate with the fuse bolts to seal the corresponding fuses. The fuse bolts have a plum blossom shape.

5. The indoor three-phase split voltage transformer with fuse according to claim 1, characterized in that: The B-phase insulator structure is as follows: the B-phase primary wiring terminal and the second fuse-end primary wiring terminal are cast with epoxy resin to form an integrated insulating support structure.

6. The indoor three-phase split voltage transformer with fuse according to claim 1, characterized in that: The B-phase primary terminal is connected to the spring in the second insulating cylinder through a screw, and the spring is in contact with the end of the second fuse; the screw is fixed to the second insulating cylinder through a primary insert, and a copper foil is provided on the primary insert, which is in contact with the semi-conductive paint.

7. The indoor three-phase split voltage transformer with fuse according to claim 1, characterized in that: The bottoms of the A-phase insulator and the C-phase insulator are both provided with a first mounting plate, and the bottom of the B-phase insulator is provided with a second mounting plate.

8. The indoor three-phase split voltage transformer with fuse according to claim 1, characterized in that: The A-phase insulator, the B-phase insulator and the C-phase insulator are arranged in a straight line, and the primary connecting wires between the B-phase primary wiring terminal and the A-phase primary wiring terminal and the C-phase primary wiring terminal are V-shaped.

Images