GIS voltage transformer based on compressed air

Abstract

The utility model relates to the technical field of voltage transformers, in particular to a GIS (Gas Insulated Switchgear) voltage transformer based on compressed air, which comprises a shell and a transformer body positioned in the shell, the upper end and the lower end of the shell are opened, the opening at the upper end of the shell is closed by a disc insulator, and the opening at the lower end of the shell is connected with a bottom plate through a connecting flange to be closed. Compressed air is filled in the shell; the transformer body comprises an iron core, a winding coil and a clamping piece, the clamping piece is fixedly connected with the bottom plate through a bolt, the iron core is of a C-shaped integrated structure and is clamped in the clamping piece, and the winding coil is in a stepped pagoda shape and is arranged on the iron core; and a high-voltage wiring terminal is arranged at the center of the disc-type insulator and is connected with the body through a conducting rod arranged in the shell. The utility model has the advantages of compact structure, small volume, high insulating strength and the like, uses compressed air as an insulating medium, and is environment-friendly.

Description

Technical Field

[0001] The utility model relates to the technical field of voltage transformers, in particular to a GIS voltage transformer based on compressed air. Background Art

[0002] Gas-insulated equipment is an irreplaceable key power transmission and transformation equipment in modern power grids. It has the characteristics of compact structure, safe operation, high stability, and little impact from environmental factors. In the operation of power grids, voltage transformers are often used, and the quality of the insulation of voltage transformers is directly related to the safe operation of the power grid.

[0003] SF6 gas is the most widely used insulating medium in the power industry because of its good arc extinguishing performance and insulation strength. However, SF6 will produce fluorine and sulfur compounds under the action of corona and arc in the electric field, which are toxic and corrosive, and will damage the insulation material, thus affecting the service life of the product.

[0004] The insulation performance of commonly used SF6 gas is 2 to 3 times that of clean air. When the performance of the main insulating medium decreases, in order to meet the insulation requirements of 220kV power stations, it is necessary to increase the product's external volume and internal inflation pressure. The disadvantage of existing technical conditions is that in order to meet the insulation performance, the internal structure of the product is not compact enough, resulting in a large volume and higher material costs. In addition, SF6 is one of the main greenhouse gases. With the emphasis on SF6 gas emission reduction, it is urgent to develop environmentally friendly gases that can replace SF6 as an insulating medium.

[0005] Compressed air is used as the insulating medium, and its global warming potential (GWP=0) is an environmentally friendly gas. It can be completely "carbon neutral" during production, use, and maintenance (considering leakage). Its gas insulation strength is not much different from SF6. Compared with SF6 gas, it has no decomposition products and is harmless to the human body. It is a truly environmentally friendly GIS. Utility Model Content

[0006] In view of the technical problems of existing SF6 gas insulation equipment such as large size and harmful gas, the utility model aims to provide a GIS voltage transformer based on compressed air, which has the advantages of compact structure, small size, high insulation strength, etc., and uses compressed air as the insulating medium, which is environmentally friendly.

[0007] The utility model provides a GIS voltage transformer based on compressed air, comprising a shell and a body located inside the shell, the shell is opened at the upper and lower ends, the upper opening of the shell is closed by a disc insulator, the lower opening of the shell is closed by connecting a flange to a bottom plate, and the shell is filled with compressed air; the body comprises an iron core, a winding coil, and a clamp, the clamp is fixedly connected to the bottom plate by bolts, the iron core is a C-shaped integrated structure and is clamped in the clamp, the winding coil is a stepped pagoda shape and is arranged on the iron core; a high-voltage terminal is arranged at the center of the disc insulator, and the high-voltage terminal is connected to the body through a conductive rod arranged inside the shell.

[0008] Furthermore, a protective cover is arranged outside the disc insulator to seal and protect the disc insulator.

[0009] Furthermore, a junction box is provided on the outer surface of the shell, and a wire outlet hole is provided at the bottom end of the junction box.

[0010] Furthermore, an air charging valve is provided on the outer surface of the shell for introducing compressed air into the interior of the shell.

[0011] Furthermore, a fully enclosed shielding cover is provided outside the conductive rod to fully enclose and insulate the conductive rod.

[0012] Furthermore, the winding coil is covered with a high-voltage shielding cover for full shielding and insulation of the winding.

[0013] Furthermore, a shielding side plate is installed on the clamp.

[0014] Furthermore, an explosion-proof device is provided on the lower surface of the bottom plate, and the explosion-proof device is connected to the inside of the shell through an explosion-proof hole provided at the center of the lower surface of the bottom plate. The explosion-proof device prevents the shell from bursting due to excessive gas pressure.

[0015] Furthermore, a bracket is provided under the shell, and the bracket is fixed to the lower surface of the shell by bolts.

[0016] Furthermore, a grounding socket is provided on the outer surface of the shell.

[0017] The beneficial effect of the utility model is that the device body of the utility model is located inside the shell, and the iron core is inside the clamp, the winding coil can be wound by an insulating tube and a copper wire, and is arranged on the iron core, the shielding side plate is installed on the clamp, and a high-voltage shielding cover is provided outside the winding coil winding to realize a fully shielded insulation structure, so the device body has the advantages of compact structure and high insulation strength, which reduces the product volume and further reduces the material cost; the coil of the utility model adopts a pagoda-shaped winding design to increase the distributed capacitance of the winding, and adopts a C-shaped integrated iron core structure, which has the characteristics of strong stability and small ferromagnetic loss compared with the laminated iron core. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the utility model or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 It is a schematic diagram of the internal structure of a specific implementation method of the utility model.

[0020] Figure 2 It is an appearance diagram of a specific implementation method of the utility model.

[0021] In the figure: 1-protection cover, 2-disc insulator, 3-shell, 4-junction box, 5-wire outlet, 6-grounding seat, 7-connection flange, 8-bracket, 9-explosion-proof device, 10-iron core, 11-clamp, 12-shielding side plate, 13-high-voltage shielding cover, 14-winding coil, 15-inflating valve, 16-conductive rod, 17-fully enclosed shielding cover. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the technical solutions in the present invention, 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 them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0023] Example 1

[0024] like Figure 1 , Figure 2 The utility model provides a GIS voltage transformer based on compressed air, including a shell 3 and a body located inside the shell 3, the shell 3 is opened at both ends, the upper and lower ends of the shell 3 are closed by a disc insulator 2, the lower end of the shell 3 is connected to a bottom plate by a connecting flange 7 and closed, and the shell 3 is filled with compressed air; the body includes an iron core 10, a winding coil 14, and a clamp 11, the clamp 11 is fixedly connected to the bottom plate by bolts, the iron core 10 is a C-shaped integrated structure and is clamped in the clamp 11, the winding coil 14 is a stepped pagoda shape and is arranged on the iron core 10; a high-voltage terminal is provided at the center of the disc insulator 2, and the high-voltage terminal is connected to the body through a conductive rod 16 arranged inside the shell 3.

[0025] A protective cover 1 is provided on the outside of the disc insulator 2. A junction box 4 is provided on the outer surface of the shell 3, and a wire outlet hole 5 is provided at the bottom end of the junction box 4. An inflation valve 15 is provided on the outer surface of the shell 3. A fully enclosed shielding cover 17 is provided on the outside of the conductive rod 16. The winding coil 14 is covered with a high-voltage shielding cover 13. A shielding side plate 12 is also installed on the clamp 11. An explosion-proof device 9 is provided on the lower surface of the bottom plate, and the explosion-proof device 9 is connected to the inside of the shell 3 through an explosion-proof hole provided at the center of the lower surface of the bottom plate. A bracket 8 is provided below the shell 3, and the bracket 8 is fixed to the lower surface of the shell 3 by bolts. A grounding seat 6 is provided on the outer surface of the shell 3.

[0026] The utility model winding coil 14 includes an insulating tube and a copper conductor, and uses a fully automatic glue spray winding process to replace the semi-automatic winding process, thereby improving the wire tension, film tension, and winding speed, which are key factors affecting product quality, and improving the coil winding quality. The utility model coil includes a primary coil and a secondary coil. The number of turns of the secondary coil is specially designed, and the rated magnetic density is 1.09T. It can ensure that the product does not have an excitation inflection point under 1.5Um. The primary coil adopts a trapezoidal structure design and is wound using a fully automatic glue spray winding machine. Imported double-sided diamond film is used between layers, and the wire specification used is 0.14 imported polyester imide enameled copper round wire.

[0027] The utility model adopts compressed air as the insulating medium. Under certain pressure and ratio conditions, its insulation performance and dielectric strength are close to those of SF6 gas. The greenhouse effect value of compressed air is much lower than that of sulfur hexafluoride, which is more environmentally friendly. By increasing the compressed air gas pressure in the voltage transformer to 0.8MPa, the insulation strength of the voltage transformer is increased. In addition, compressed air has a lower liquefaction temperature, which can meet the needs of a wide range of applications and low-temperature areas under the same air pressure, and reduce environmental pollution.

[0028] The utility model adopts a fully shielded insulation structure for the winding, so the device body has the advantages of compact structure, high insulation strength, etc., which reduces the volume of the product and further reduces the material cost.

[0029] Although the present invention is described in detail by referring to the accompanying drawings and in combination with the preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, a person skilled in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and these modifications or substitutions shall be within the scope of the present invention. Any person skilled in the art who is familiar with the present technical field may easily think of changes or substitutions within the technical scope disclosed in the present invention, and these shall be within the scope of protection of the present invention.

Claims

1. A GIS voltage transformer based on compressed air, comprising a housing and a body located inside the housing, characterized in that: The upper and lower ends of the shell are open, the upper opening of the shell is closed by a disc insulator, and the lower opening of the shell is closed by connecting the flange to the bottom plate, and the shell is filled with compressed air; the body includes an iron core, a winding coil, and a clamp, the clamp is fixedly connected to the bottom plate by bolts, the iron core is a C-shaped integrated structure and is clamped in the clamp, the winding coil is a stepped pagoda shape and is arranged on the iron core; a high-voltage terminal is provided at the center of the disc insulator, and the high-voltage terminal is connected to the body through a conductive rod arranged inside the shell.

2. The compressed air-based GIS voltage transformer according to claim 1, characterized in that: The disc insulator is provided with a protective cover.

3. The compressed air-based GIS voltage transformer according to claim 1, characterized in that: A junction box is arranged on the outer surface of the shell, and a wire outlet hole is arranged at the bottom end of the junction box.

4. The compressed air-based GIS voltage transformer according to claim 1, characterized in that: An air charging valve is arranged on the outer surface of the shell.

5. The compressed air-based GIS voltage transformer according to claim 1, characterized in that: A fully enclosed shielding cover is provided outside the conductive rod.

6. The compressed air-based GIS voltage transformer according to claim 1, characterized in that: The winding coil is covered with a high voltage shielding cover.

7. The GIS voltage transformer based on compressed air according to claim 1, characterized in that: A shielding side plate is also mounted on the clamp.

8. The GIS voltage transformer based on compressed air according to claim 1, characterized in that: An explosion-proof device is arranged on the lower surface of the bottom plate, and the explosion-proof device is communicated with the inside of the shell through an explosion-proof hole arranged at the center of the lower surface of the bottom plate.

9. The compressed air-based GIS voltage transformer according to claim 1, characterized in that: A bracket is provided under the shell, and the bracket is fixed to the lower surface of the shell by bolts.

10. The compressed air-based GIS voltage transformer according to claim 1, characterized in that: A grounding seat is arranged on the outer surface of the shell.

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