Indoor three-phase voltage transformer with fuse

Abstract

The utility model relates to high-voltage measurement or relay protection equipment of an electric power system, in particular to an indoor three-phase voltage transformer with a fuse. Comprising a main insulator and A-phase and C-phase transformer body coils sealed in the main insulator, fuse cavities are formed in the two sides of the top of the main insulator, shielding assemblies and fuses are arranged in the fuse cavities, fuse end primary wiring terminals are arranged at the tops of the fuse cavities, B-phase primary wiring terminals are arranged in the middle of the main insulator, and the A-phase and C-phase transformer body coils are arranged in the B-phase and C-phase transformer body coils. And the common B end of the A phase and the C phase is connected with the B-phase primary wiring terminal. The cavity of the fuse is provided with the shielding structure, so that the space is effectively utilized, the overall occupied space of the product is small, the miniaturization of the product is facilitated, the size is small, the weight is light, the functions are complete, the fuse protection is realized, and the fuse is more suitable for being matched with a novel voltage transformer of a switch cabinet.

Description

Technical Field

[0001] The utility model relates to high-voltage measurement or relay protection equipment for an electric power system, in particular to an indoor three-phase 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 the miniaturization of switch cabinet and convenient maintenance, ordinary three-phase voltage transformer has disadvantages such as large size, complex installation, heavy lifting, etc. At the same time, the transformer has a single structure and rough appearance, which makes the switch cabinet produced with it also have defects such as large size. In order to realize the miniaturization of switch cabinet equipment, flexible installation, more fitting and compact structure, and smoother product appearance along the surface structure and other functional characteristics, it is urgent to design a small-volume, full-function three-phase voltage transformer with fuse. Utility Model Content

[0003] In view of the above problems, the purpose of the utility model is to provide an indoor three-phase voltage transformer with fuse to solve the problems of large size, heavy weight, and difficulty in transportation and installation of existing three-phase voltage transformers.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0005] The utility model provides an indoor three-phase voltage transformer with fuse, comprising a main insulator and A-phase and C-phase body coils sealed in the main insulator, fuse cavities are arranged on both sides of the top of the main insulator, shielding components and fuses are arranged in the fuse cavity, a fuse end primary wiring terminal is arranged on the top of the fuse cavity, a B-phase primary wiring terminal is arranged on the top of the main insulator, and a common B-terminal of the A-phase and C-phase is connected to the B-phase primary wiring terminal.

[0006] The fuse cavity is a cylindrical structure, the inner end of the fuse cavity is provided with a primary insert, and the fuse is abutted against the primary insert through a spring; the outer end of the fuse cavity is provided with a fuse screw sleeve, the fuse screw sleeve is threadedly connected to the fuse bolt, and a sealing gasket is provided between the fuse bolt and the fuse screw sleeve.

[0007] The shielding assembly includes a screw sleeve shielding net and a shielding net, wherein the shielding net is arranged at the inner end of the fuse cavity and connected to the primary insert; the screw sleeve shielding net is arranged at the outer end of the fuse cavity and connected to the fuse screw sleeve, and a gap is left between the screw sleeve shielding net and the shielding net.

[0008] The B-phase primary wiring terminal and the two fuse-end primary wiring terminals are arranged in a herringbone shape, and umbrella skirts are provided between the B-phase primary wiring terminal and the two fuse-end primary wiring terminals.

[0009] The B-phase primary wiring terminal is lower than the two fuse-end primary wiring terminals.

[0010] The main insulator and the fuse cavity are cast into an integrated structure using epoxy resin and the A and C phase body coils.

[0011] The main insulator is in a cubic shape with front and rear inclined transitions. A secondary wiring platform is provided at the bottom of the front end of the main insulator. Secondary wiring terminals are embedded in the secondary wiring platform. A secondary protective cover is provided above the secondary wiring platform.

[0012] The main insulator is arranged on a mounting base plate, and a grounding terminal is arranged on the rear side of the mounting base plate.

[0013] The utility model has the following advantages and beneficial effects:

[0014] 1. Small size, light weight, and full functions: The utility model optimizes the structural design, and a new shielding structure with two shielding nets is arranged on the outside of the fuse cavity, which effectively utilizes the space. The overall product occupies a small space, which is more conducive to product miniaturization. It has a small size, light weight, full functions, and fuse protection, and is more suitable for use with a new type of voltage transformer supporting the switch cabinet;

[0015] 2. Simple operation, convenient installation and easy maintenance: The utility model adds two shielding nets when assembling the mold, which is simple to operate. When installing and using the product, you only need to install the mutual inductor in the switch cabinet according to the phase sequence A, B, and C terminals, which effectively saves the assembly time of the switch cabinet; the product is simpler to overhaul and does not require special maintenance work; once the A and C phases are equipped with fuse protection, wiring can be performed without removing the fuse, which is convenient to install and easy to maintain;

[0016] 3. Uniform electric field and small local discharge: Two shielding nets are arranged on the outside of the cylindrical cavity of phases A and C of the utility model, and the primary high-voltage fuse is placed in the fuse cavity, which has good shielding effect, uniform electric field inside and outside the product, small local discharge of the product, and safe and reliable operation of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the internal structure of an indoor three-phase voltage transformer with fuse according to the utility model;

[0018] Figure 2 This is a front view of an indoor three-phase voltage transformer with fuse according to the utility model;

[0019] Figure 3 for Figure 2 Left view of;

[0020] Figure 4 for Figure 2 Top view of the .

[0021] In the figure: 1. iron core; 2. secondary winding; 3. insulation frame; 4. primary winding; 5. body coil; 6. secondary terminal block; 7. secondary protective cover; 8. mounting base; 9. grounding terminal; 10. main insulator; 11. fuse bolt; 12. primary terminal of fuse end; 13. fuse; 14. umbrella skirt; 15. sealing gasket; 16. fuse screw sleeve; 17. primary insert; 18. spring; 19. primary terminal of phase B; 20. screw sleeve shielding net; 21. shielding net. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] like Figures 1 to 4 As shown, the utility model provides an indoor three-phase voltage transformer with fuse, including a main insulator 10 and a body coil 5 of phases A and C sealed in the main insulator 10, fuse cavities are provided on both sides of the top of the main insulator 10, a shielding assembly and a fuse 13 are provided in the fuse cavity, a fuse end primary terminal 12 is provided on the top of the fuse cavity, a B-phase primary terminal 19 is provided on the top of the main insulator 10, and the common B end of phases A and C is connected to the B-phase primary terminal 19.

[0024] like Figures 1 to 4 As shown, in the embodiment of the present invention, the main insulator 10 and the fuse cavity are cast into an integrated structure using epoxy resin and the body coil 5 of the A and C phases. The main insulator 10 is a square body with a front and rear inclined transition. A secondary wiring platform 6 is provided at the bottom of the front end of the main insulator 10. The secondary wiring platform 6 is embedded with secondary wiring terminals. A secondary protective cover 7 is provided above the secondary wiring platform 6.

[0025] Furthermore, the main insulator 10 is disposed on the mounting base plate 8 , and a grounding terminal 9 is disposed at the rear bottom of the main insulator 10 .

[0026] like Figure 1 As shown, in the embodiment of the present invention, the fuse cavity is a cylindrical structure, the inner end of the fuse cavity is provided with a primary insert 17, and the fuse 13 is abutted against the primary insert 17 through a spring 18; the outer end of the fuse cavity is provided with a fuse screw sleeve 16, the fuse screw sleeve 16 is threadedly connected and fastened with the fuse bolt 11, and a sealing gasket 15 is provided between the fuse bolt 11 and the fuse screw sleeve 16 to ensure reliable sealing of the fuse. Specifically, the shape of the fuse bolt 11 is a plum blossom shape, which is convenient for manual installation or replacement of the fuse without disassembly of the primary wiring, and the installation is very convenient.

[0027] In an embodiment of the present invention, the shielding assembly includes a screw sleeve shielding mesh 20 and a shielding mesh 21, wherein the shielding mesh 21 is arranged at the inner end of the fuse cavity and connected to the primary insert 17; the screw sleeve shielding mesh 20 is arranged at the outer end of the fuse cavity and connected to the fuse screw sleeve 16, and a gap is left between the screw sleeve shielding mesh 20 and the shielding mesh 21 to ensure that the primary high-voltage terminal is completely shielded and the electric field is evenly distributed.

[0028] Preferably, the B-phase primary terminal 19 and the two fuse-end primary terminals 12 are arranged in a herringbone shape, and an umbrella skirt 14 is provided between the B-phase primary terminal 19 and the two fuse-end primary terminals 12 .

[0029] Furthermore, the B-phase primary wiring terminal 19 is arranged on a boss at the rear end of the symmetry axis of the main insulator 10 , and the B-phase primary wiring terminal 19 is lower than the two fuse-end primary wiring terminals 12 .

[0030] like Figure 1 As shown, in the embodiment of the present invention, the structure of the body coil 5 of the A and C phases is the same, both including an iron core 1, a secondary winding 2, an insulating frame 3 and a primary winding 4, wherein the secondary winding 2 is wound on the iron core 1, and the primary winding 4 is wound on the insulating frame 3 and then integrally sheathed on the outside of the secondary winding 2.

[0031] The utility model provides an indoor three-phase voltage transformer with fuse, and its preparation process is:

[0032] The secondary winding 2 is wound on the iron core 1, and the primary winding 4 is wound on the insulating frame 3 and then integrally sheathed on the outside of the secondary winding 2. After the iron core is assembled, insulated and buffered, it becomes the A and C phase body coils 5, and then fixed in the casting mold. First, the primary insert 17 and the shielding net 21 are connected, and then the screw sleeve shielding net 20 is fixed, and then the primary insert 17 is fixed on each tire core together with the shielding net 21, and the primary terminal 12 of the fuse end is fixed; the common B end of the A and C phases is crimped together with a tubular bare terminal crimping pliers and then connected to the B phase primary terminal 19, removing the tin welding operation link, and the same electrical reliability The fuse screw sleeve 16 is connected to the primary terminal 12 of the fuse end, the secondary terminal 6 is connected, the insulation distance is adjusted, and the main insulator 10 is formed by vacuum casting and curing of epoxy resin, and finally the whole is installed on a mounting base plate 8; then it becomes: the A and C phases are axially symmetrical, each with an umbrella skirt 14 protruding in the middle, and the front and rear inclined transitions of the fuse 13 are arranged in the upper fuse cavity, and the overall shape is a cube, which makes the mutual inductor structure more suitable and compact, and the product appearance is smooth along the surface structure, ensuring uniform insulation and easy dust and other dirt to fall off, meeting the environmental requirements of high pollution areas.

[0033] During the assembly of the finished product, the end face of the primary insert 17 is pressed by the spring 18 to ensure reliable contact between the fuse 13 and the primary insert 17. The grounding terminal 9 is provided on the mounting base plate 8, and the grounding terminal 9 is located in the middle of the rear side of the main insulator 10, facilitating safe and reliable grounding of the product.

[0034] During use, first fix the mounting base plate 8 of the voltage transformer on the switch cabinet chassis. The A, B, and C phase wiring terminals are arranged in a "pin" shape. The B-phase terminal is lower than the A and C phase terminals, facilitating inter-phase wiring. Connect the primary wiring terminals of the product in parallel to the high-voltage side of the line according to the three-phase "V" type wiring. Finally, connect the low-voltage secondary cable to the secondary wiring terminal and install the anti-tampering secondary protective cover 7. The installation of the three-phase fuse voltage transformer is completed.

[0035] A kind of indoor three-phase fuse voltage transformer provided by the utility model is a new product designed completely in accordance with national standards and switch cabinet technical requirements. It adopts a wound core and uses the electromagnetic conversion principle to enable the secondary voltage to accurately reflect the change of the primary voltage, and is used for voltage measurement and relay protection. The product has the advantages of small volume, light weight, complete functions, large capacity, convenient installation, easy maintenance, stable insulation, and safe operation. The addition of fuses on the primary A and C phases further improves the design and manufacturing level of the voltage transformer ring main unit.

[0036] The above is only the implementation mode of the utility model and is not used to limit the protection scope of the utility model. Any modification, equivalent replacement, improvement, expansion, etc. made within the spirit and principle of the utility model are included in the protection scope of the utility model.

Claims

1. An indoor three-phase voltage transformer with fuse, characterized in that: The invention comprises a main insulator (10) and A-phase and C-phase body coils (5) sealed in the main insulator (10); fuse cavities are arranged on both sides of the top of the main insulator (10); a shielding assembly and a fuse (13) are arranged in the fuse cavity; a fuse end primary wiring terminal (12) is arranged on the top of the fuse cavity; a B-phase primary wiring terminal (19) is arranged on the top of the main insulator (10); and a common B-end of the A-phase and C-phase is connected to the B-phase primary wiring terminal (19).

2. The indoor three-phase voltage transformer with fuse according to claim 1, characterized in that: The fuse cavity is a cylindrical structure. A primary insert (17) is provided at the inner end of the fuse cavity. The fuse (13) abuts against the primary insert (17) via a spring (18). A fuse screw sleeve (16) is provided at the outer end of the fuse cavity. The fuse screw sleeve (16) is threadedly connected to a fuse bolt (11). A sealing gasket (15) is provided between the fuse bolt (11) and the fuse screw sleeve (16).

3. The indoor three-phase voltage transformer with fuse according to claim 2, characterized in that: The shielding assembly comprises a screw sleeve shielding net (20) and a shielding net (21), wherein the shielding net (21) is arranged at the inner end of the fuse cavity and connected to the primary insert (17); the screw sleeve shielding net (20) is arranged at the outer end of the fuse cavity and connected to the fuse screw sleeve (16), and a gap is left between the screw sleeve shielding net (20) and the shielding net (21).

4. The indoor three-phase voltage transformer with fuse according to claim 1, characterized in that: The B-phase primary wiring terminal (19) and the two fuse-end primary wiring terminals (12) are arranged in a herringbone shape, and an shed (14) is provided between the B-phase primary wiring terminal (19) and the two fuse-end primary wiring terminals (12).

5. The indoor three-phase voltage transformer with fuse according to claim 4, characterized in that: The B-phase primary wiring terminal (19) is lower than the two fuse-end primary wiring terminals (12).

6. The indoor three-phase voltage transformer with fuse according to claim 1, characterized in that: The main insulator (10) and the fuse cavity are cast into an integrated structure using epoxy resin and the A and C phase body coils (5).

7. The indoor three-phase voltage transformer with fuse according to claim 6, characterized in that: The main insulator (10) is in the shape of a square body with transitions between front and rear inclined surfaces. A secondary wiring platform (6) is provided at the bottom of the front end of the main insulator (10). A secondary wiring terminal is embedded in the secondary wiring platform (6). A secondary protective cover (7) is provided above the secondary wiring platform (6).

8. The indoor three-phase voltage transformer with fuse according to claim 7, characterized in that: The main insulator (10) is arranged on a mounting base plate (8), and a grounding terminal (9) is arranged on the rear side of the mounting base plate (8).

Images