CN111354540A

CN111354540A - Current transformer used in air chamber

Info

Publication number: CN111354540A
Application number: CN201811561931.3A
Authority: CN
Inventors: 李涛昌; 王仁焘; 宋仁丰; 赵阳武; 高琦; 初立成; 王振宇
Original assignee: Dalian North Instrument Transformer Group Co Ltd
Current assignee: Dalian North Instrument Transformer Group Co Ltd
Priority date: 2018-12-20
Filing date: 2018-12-20
Publication date: 2020-06-30

Abstract

The invention relates to a high-voltage measuring device of an electric power system, in particular to a current transformer used in an air chamber. The coil body comprises an insulator and a coil body arranged in the insulator in a sealing mode, wherein the insulator comprises an insulating base and a horizontal insulating upper body arranged on the insulating base, a primary wire inlet wiring terminal and a primary wire outlet wiring terminal are arranged at the front end and the rear end of the insulating upper body respectively, a secondary wiring platform is arranged at the end part of the insulating base, the insulating upper body is of a cylindrical structure, the end surfaces of two sides of the insulating upper body are planes, the insulating base is of an elliptical platform structure, a sealing groove is formed in the edge of the bottom of the insulating base along the circumferential direction, and a plurality of embedded nuts are uniformly arranged. The invention is formed by vacuum casting of special epoxy resin, and has the advantages of small volume, flexible installation, high metering precision, flexible parameters, reliable insulation, wide application and the like.

Description

Current transformer used in air chamber

Technical Field

The invention relates to a high-voltage measuring device of an electric power system, in particular to a current transformer used in an air chamber.

Background

The current transformer is a device for measuring current, electric energy and relay protection in an electric power system or an electric control system, in recent years, metal enclosed switchgear (C-GIS for short) taking SF6 as an insulating medium has the advantages of small volume, high operation safety, suitability for various environments such as high altitude, high humidity and the like, and is generally popularized and applied; the matched current transformer is positioned outside the high-voltage air chamber, a bus-through structure is adopted, and the matched primary high-voltage insulated cable is used as a primary winding, because of structural limitation, the current transformer can only be used in a large transformation ratio range, and the accuracy and the precision of a small current transformation ratio are difficult to guarantee; therefore, the application range of the similar switch cabinet equipment is limited, and the whole equipment has the problems of slightly large volume, more parts, low metering protection precision and the like, so that a current transformer which can be directly arranged in a gas chamber of a gas insulation switch cabinet is particularly needed in switch cabinet manufacturers and markets.

Disclosure of Invention

In view of the above problems, an object of the present invention is to provide a current transformer for use in an air chamber, so as to solve the problems of low precision, complex installation, many components, slightly large overall structure, etc. of the current transformer for the existing gas insulated switchgear.

In order to achieve the purpose, the invention adopts the following technical scheme:

the utility model provides an use current transformer in air chamber, includes the insulator and seals and arrange in the coil ware body in the insulator, wherein the insulator include insulator foot stall with set up in horizontal insulating upper part of the body on the insulator foot stall, the front and back end of insulating upper part of the body is equipped with once inlet wire binding post and once outlet wire binding post respectively, the tip of insulator foot stall is equipped with secondary wiring platform.

The insulating upper body is of a cylindrical structure, and the end faces on the two sides are planes.

The insulating base is of an elliptical table structure, a sealing groove is formed in the edge of the bottom of the insulating base along the circumferential direction, and a plurality of embedded nuts are uniformly arranged around the elliptical periphery of the inner side of the sealing groove in an encircling mode.

The outer side end face of the insulating base is protruded with a small elliptical table structure, and the secondary wiring table is located in the concave position in the middle of the small elliptical table structure.

The primary incoming line wiring terminal is a cylindrical wire board which is embedded into the insulator and partially exposed and provided with a threaded hole.

The primary outgoing line wiring terminal is a cylindrical wire board which is embedded in the insulator and partially exposed and provided with a threaded hole.

The coil body comprises an iron core, a primary winding and a secondary winding, wherein the secondary winding is wound on the iron core, the primary winding penetrates through the center of the secondary winding, two ends of the primary winding are respectively connected with the primary wire inlet wiring terminal and the primary wire outlet wiring terminal, and the secondary wiring terminal of the secondary winding is led out from the secondary wiring table.

And a secondary winding bracket for supporting the secondary winding is arranged in the insulating base.

The insulator is of an integrated structure poured by epoxy resin.

The invention has the advantages and beneficial effects that:

the invention has the following advantages and beneficial effects:

1. small, the installation is nimble: the invention is integrally formed by pouring epoxy resin, has more compact structure, can flexibly realize electrical and mechanical connection with a main bus conductor in a high-pressure gas chamber by a flat connection plate at the primary inlet and outlet ends and a vertical mode, and ensures that the product and a gas chamber shell are more reasonably and quickly sealed and installed by special design at the bottom of the product.

2. The measurement precision is high, the parameter is nimble: the internal metering winding of the invention adopts superconducting magnetic material, the precision can reach 0.2S level, the high precision of metering under the conditions of wide load and large load change is ensured, the internal part of the product can be made into a multi-winding structure according to the requirement, and the parameter combination is more flexible.

3. Reliable insulation and wide application: the whole body is cast by adopting a special epoxy resin material, the performance degradation phenomenon caused by the corrosion of sulfur hexafluoride gas can not occur in the long-term use process, the insulating performance is very stable, the whole body and a primary high-voltage conductor element in a gas chamber are arranged in the sulfur hexafluoride insulating gas, are not contacted with various external severe environments, and can be applied to various working condition projects.

Drawings

FIG. 1 is a front view of the present invention;

FIG. 2 is a side view of FIG. 1;

FIG. 3 is a bottom view of FIG. 1;

fig. 4 is a schematic view of the internal structure of the present invention.

In the figure: 1 is an iron core; 2 is a primary winding; 3 is a secondary winding; 4 is a primary incoming line wiring terminal; 5 is a primary outgoing line wiring terminal; 6 is a secondary wiring table; 7, sealing grooves; 8 is an embedded nut; 9 is an insulated upper body; 10 is a secondary winding support, 11 is a secondary wiring terminal, and 12 is an insulating base.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

As shown in fig. 1 to 3, the current transformer for use in an air chamber provided by the present invention comprises an insulator and a coil body sealed in the insulator, wherein the insulator comprises an insulating base 12 and a horizontal insulating upper body 9 arranged on the insulating base 12, a primary incoming line terminal 4 and a primary outgoing line terminal 5 are respectively arranged at the front end and the rear end of the insulating upper body 9, and a secondary wiring platform 6 is arranged at the end of the insulating base 12.

The insulator adopts epoxy resin to pour into an integral type structure, and the long-term application process can not appear material performance degradation in the air chamber, guarantees to have good insulating properties. The insulating upper body 9 is of a cylindrical structure, and the end faces on the two sides are planes. The insulating base 12 is of an elliptical table structure, the bottom edge of the insulating base is provided with a sealing groove 7 along the circumferential direction, and a plurality of embedded nuts 8 are uniformly and annularly arranged on the elliptical periphery close to the inner side of the sealing groove 7.

The outer side end face of the insulating base 12 is protruded with a small elliptical table structure, and the secondary wiring table 6 is located in the concave position in the middle of the small elliptical table structure, so that the secondary cable is convenient to electrically connect.

The primary incoming line wiring terminal 4 is a cylindrical wire board with a threaded hole, which is embedded in the insulator and partially exposed. The primary outgoing line wiring terminal 5 is a cylindrical wire board with a threaded hole, which is embedded in the insulator and partially exposed.

As shown in fig. 4, the coil body includes an iron core 1, a primary winding 2 and a secondary winding 3, wherein the secondary winding 3 is wound on the iron core 1, the primary winding 2 passes through a central hole of the secondary winding 3, and both ends of the primary winding are respectively connected with a primary incoming line connection terminal 4 and a primary outgoing line connection terminal 5, and a secondary connection terminal 11 of the secondary winding 3 is led out from a secondary connection platform 6. A secondary winding support 11 for supporting the secondary winding 3 is arranged in the insulating base 12.

The manufacturing process of the invention is as follows:

the secondary winding 3 is uniformly wound on the circular iron core 1, the primary winding 2 is wound by using a special tool and is assisted in binding insulating materials, and after the secondary winding 3 is bound and buffered by using a secondary winding support 10, a coil body with a primary incoming wire connecting terminal 4, a primary outgoing wire connecting terminal 5, the primary winding 2, the secondary winding 3 and a secondary connecting terminal 11 is formed; the secondary winding 3 is fixed on a die by using a secondary winding support 10, the primary winding 2 is fixed on the die by adopting a primary incoming line wiring terminal 4 and a primary outgoing line wiring terminal 5, the distance is adjusted and then the primary winding is formed by vacuum pouring and curing by using special epoxy resin, and then the primary outgoing line wiring terminal 4, the primary outgoing line wiring terminal 5, the secondary wiring table 6 and the like form an integrated structure, so that the material performance degradation cannot occur in the long-term application process in an air chamber, and the good insulating property is ensured. The bottom of the integrated structure is designed into an elliptical table, the size of the integrated structure is matched with a window of an air chamber, the inner side elliptical ring is internally provided with a concave sealing groove 7, the cross section of the integrated structure is in a shape of a rounded rectangle and is used as a sealing ring for positioning during matched installation, the integrated structure is close to the inner side elliptical periphery of the sealing groove, a plurality of embedded nuts 8 are uniformly arranged in a surrounding mode, and reliable sealing of the mutual inductor and the air chamber is realized through fasteners such as bolts. The middle part of the bottom of the elliptical table is designed to be in a small elliptical table convex form, and the secondary wiring table 6 is located in the concave position in the middle, so that the secondary cable is convenient to electrically connect. The main insulator is in a cylindrical shape, and two ends of the main insulator are annular planes, so that the main insulator can be flexibly arranged among various components in a high-pressure air chamber of the switch cabinet. The primary wire inlet wiring terminal 4 is a cylindrical wire plate with a threaded hole, which is embedded in the casting body and partially exposed, and the primary wire outlet wiring terminal 5 is a cylindrical wire plate with a threaded hole, which is embedded in the casting body and partially exposed, so that the electrical and mechanical connection with a high-voltage conductor in a high-voltage air chamber of the switch cabinet is flexibly realized. The internal metering winding is made of superconducting magnetic materials, the precision can reach 0.2S level, the high precision of metering under the conditions of wide load and large load change is guaranteed, a multi-winding structure can be made inside the product according to requirements, and the parameter combination is more flexible. The integral primary high-voltage conductor element in the gas chamber is arranged in sulfur hexafluoride insulating gas, is not contacted with various external severe environments, and can be applied to engineering under various working conditions.

When the device is used, the product is installed in a main bus air chamber of a switch cabinet in a side-mounted or normal-mounted mode, a primary bus is firstly connected with a primary inlet and outlet wire and other high-voltage components in a related mode, then the device is hermetically fixed with an air chamber shell through bolts, sealing rings and the like, then a secondary cable is connected, and after the other high-voltage components of the switch are installed, the air chamber is inflated and insulated through a sulfur hexafluoride inflating device, namely the device is installed.

The invention relates to a current transformer used in an air chamber matched with an SF6 gas insulation switch cabinet, which is a new product designed completely according to the national standard and the special requirements of an inflatable switch cabinet, adopts a rolled iron core, utilizes the electromagnetic conversion principle to ensure that the secondary current can accurately reflect the change condition of the primary current and is used as equipment for measuring current, electric energy and relay protection.

The above description is only an embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, improvement, extension, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. The utility model provides a use current transformer in air chamber which characterized in that, includes the insulator and seals and arrange in the body of coil ware in the insulator, wherein the insulator include insulator foot (12) and set up in horizontal insulating upper part of the body (9) on insulator foot (12), the front and back end of insulating upper part of the body (9) is equipped with once inlet wire binding post (4) and once outlet wire binding post (5) respectively, the tip of insulator foot (12) is equipped with secondary terminal connection platform (6).

2. The current transformer for use in a gas chamber according to claim 1, wherein the insulating upper body (9) has a cylindrical structure, and both side end surfaces are flat surfaces.

3. The current transformer for use in the air chamber according to claim 1, wherein the insulating base (12) is of an elliptical platform structure, a sealing groove (7) is formed in the bottom edge along the circumferential direction, and a plurality of embedded nuts (8) are uniformly and annularly arranged near the inner elliptical periphery of the sealing groove (7).

4. The current transformer for use in a gas chamber according to claim 3, wherein the outer end face of the insulating base (12) is protruded with a small elliptical table structure, and the secondary junction block (6) is located at a recessed position in the middle of the small elliptical table structure.

5. The current transformer for use in the air chamber according to claim 1, wherein the primary incoming line terminal (4) is a cylindrical wire plate with a threaded hole embedded in the insulator and partially exposed.

6. The current transformer for use in the gas chamber according to claim 1, wherein the primary outlet terminal (5) is a cylindrical wire plate with a threaded hole embedded in the insulator and partially exposed.

7. The current transformer used in the air chamber according to claim 1, wherein the coil body comprises an iron core (1), a primary winding (2) and a secondary winding (3), wherein the secondary winding (3) is wound on the iron core (1), the primary winding (2) passes through the center of the secondary winding (3), two ends of the primary winding are respectively connected with the primary wire inlet connection terminal (4) and the primary wire outlet connection terminal (5), and the secondary connection terminal (11) of the secondary winding (3) is led out from the secondary connection terminal (6).

8. The current transformer for use in a gas chamber according to claim 7, characterized in that a secondary winding support (11) for supporting said secondary winding (3) is provided in said insulating base (12).

9. The in-plenum current transformer of claim 1, wherein said insulator is an epoxy resin cast one-piece structure.