CN2457712Y - Dry high voltage current mutual inductor - Google Patents

Abstract

The utility model discloses a dry high-voltage current mutual inductor, which is a reverse arrangement type. The utility model is characterized in that a secondary winding is positioned at the head of a mutual inductor; a primary winding penetrates through the center of the secondary winding; the secondary winding and a wire leading tube thereof are wrapped with a main insulator with a capacitance voltage-sharing screen outside, and the secondary winding and the wire leading tube are fixed in a glass fiber reinforced plastic insulating tube which is stuck with a silicon rubber shed; the spare space in the glass fiber reinforced plastic insulating tube is filled with solidifiable insulating resin. The utility model completely adopts solid organic insulating material, oil and gas are not charged, so the utility model has the advantages of no leakage, no fire hazard, and no maintenance. The utility model adopts inverse arrangement type, so the utility model has the advantage of good active thermal stability.

Description

A kind of Dry Type High Tension Current Transformer

The utility model relates to a kind of high-tension current inductor, does not particularly have the Dry Type High Tension Current Transformer of oil, no gas, no porcelain.

At present, the employed high-tension current inductor of high pressure and supergrid mainly contains two kinds of structures: just vertical and inverted.A winding of positive vertical structure is generally " U " font, and main insulation is paperwrapped on winding, and secondary winding is enclosed within the lower end of " U " font structure; Inverted structure is then opposite, and main insulation surrounds on the secondary winding, and secondary winding is positioned at the head of instrument transformer, so be called inverted.The major advantage of positive vertical structure is simple in structure, is easy to make, and shortcoming is that dynamic thermal stability is poor; And inverted structure major advantage is that a winding is short, do not twine main insulation on it again, so dynamic thermal stability is good, and shortcoming is that head is heavier, and mechanical stability is not as just vertical instrument transformer.The positive vertical structure of the many employings of high-voltage mutual inductor that 220kV is following, and inverted instrument transformer is used for the above supergrid of 220kV more: it is more that external inverted structure is used, and domestic positive vertical structure is more.In the last few years, the Power System Shortcuts capacity was increasing, and the dynamic thermal stability under the current transformer short-circuit condition has been proposed more and more higher requirement, and therefore, the following high-tension current inductor of 220kV also more and more adopts inverted structure.

The present high-tension current inductor that uses, its main insulation mainly contains three kinds: oil-impregnated paper insulation (filling type), sulphur hexafluoride (SF ₆) insulation (gas-filled type), solid insulation (dry type).The existing positive vertical structure of filling type high-tension current inductor also has inverted structure; Gas-filled type is mainly inverted structure: filling type and gas-filled type current transformer cause seepage easily, pollute, and oil-filled mutual inductor also sets off an explosion and fire easily, for guaranteeing safe operation, need test every year, overhaul, and maintenance workload is big.For Dry Type High Tension Current Transformer has appearred in head it off, disclose a kind of like this Dry Type High Tension Current Transformer such as the Chinese utility model patent specification of the CN2362184Y of on February 2nd, 2000 bulletin.What this high-tension current inductor adopted is just vertical " U " font structure, and its major advantage is not have oil, no gas (SF ₆), no porcelain, volume is little, in light weight, pollution flashover voltage is high, be convenient to installation and maintenance, reliable.This also just Dry Type High Tension Current Transformer the advantage that should possess.Yet the Dry Type High Tension Current Transformer of this pattern, himself design feature (just vertical) have determined its inherent defect, and promptly dynamic thermal stability is poor, is difficult to accomplish bigger short circuit current.Dry Type High Tension Current Transformer does not still have inverted constructed products at present.

The purpose of this utility model is to overcome the shortcoming of above prior art, a kind of Dry Type High Tension Current Transformer is provided, this high-tension current inductor adopts inverted structure, solid organic material insulation, both had the good dynamic thermal stability of inverted structure, and had dry-type high-voltage electrical equipment again and do not have oil, no gas (SF ₆), no porcelain, volume is little, in light weight, pollution flashover voltage is high, no fire hazard, advantage such as non-maintaining substantially.

For achieving the above object, the utility model Dry Type High Tension Current Transformer contains cored secondary winding and one with several (determining quantity as required) and is used for the steel pipe that secondary line draws and is fixed together, and forms " T " font structure.The lead-out wire of secondary winding passes from central tube, receives on the terminal in the secondary connection box.The surface of secondary winding that fixes and secondary lead wires pipe coats processing with semiconductive material, and in order to eliminate the burr wedge angle, surface treated constitutes the ground electric screen.Ground electric screen external solid organic insulation film is made main insulation, and when the pre-designed number of plies, lay with the middle electric screen that conducts electricity or semiconductive film is made, stagger gradually in the position of electric screen on short transverse, when assurance was radially all pressed, axially the voltage distribution also was uniform.The last layer electric screen (high pressure electric screen) all coats the main insulation of wrapping up on the secondary winding, and carries out equipotential with a winding and connect.The fiberglass insulating tube lower end splicing that is stained with the silicon rubber full skirt has metal flange, glued joint the upper end the EHT cage carriage, the secondary winding and the secondary lead wires pipe that wrap state-owned main insulation are installed in the cavity of formations such as EHT cage, EHT cage carriage, fiberglass insulating tube, winding passes from the centre bore of secondary winding, and the fairlead carriage is fixed secondary lead wires pipe lower end.Connection seam between EHT cage, Primary Conductor, EHT cage carriage, glass reinforced plastic pipe, the fairlead carriage seals with fluid sealant.Be surrounded by the excess room that constitutes with EHT cage, EHT cage carriage, fiberglass insulating tube, fairlead support etc. outside the secondary winding of main insulation and the secondary lead wires pipe with curable insulating resin filling.

Adopt said structure, because main insulation adopts the SOLID ORGANIC insulation film to make, excess room in the fiberglass insulating tube is filled with the insulating resin that can solidify, need not oil-filled or inflation, therefore reached do not have oil, no gas, no porcelain, no fire hazard, requirement such as non-maintaining substantially; Simultaneously, adopt inverted structure, do not twine main insulation on the winding, and length is short, reached the purpose that improves the dynamic and thermal stability level.

From the above, the utility model Dry Type High Tension Current Transformer is made up of winding, secondary winding, main insulation, electric screen, secondary lead wires pipe, fiberglass insulating tube, silicon rubber full skirt, insulation filling resin etc.Be characterized in: main insulation and filling insulation are solid material.

Further improve as of the present utility model, middle electric screen not only has at secondary lead wires pipe position, and extends upward, and secondary winding is encased.After adopting this structure, more help wrapping up the interior Electric Field Distribution of main insulation of secondary winding,, help reducing main insulation thickness particularly to the superhigh pressure dry-type current transformer.

Further improve as of the present utility model, the secondary lead wires pipe can be made toroidal.After adopting this structure, diameter was roughly suitable up and down after the secondary lead wires pipe had wrapped up main insulation, was approximately cylindrical, helped reducing the consumption of insulation filling resin, had also increased the mechanical strength of instrument transformer root simultaneously.

In sum, the utility model has the advantages that: adopt the SOLID ORGANIC insulating material to make fully, not oil-filled, do not inflate, therefore ne-leakage, no fire hazard, non-maintaining substantially: simultaneously, adopt inverted structure, do not twine main insulation on the winding, and length is short, so dynamic thermal stability is good.

Below in conjunction with accompanying drawing the utility model is described in further detail.

Fig. 1 is the utility model schematic diagram.

Fig. 2 further improves schematic diagram for the utility model.

The utility model Dry Type High Tension Current Transformer by winding 1, EHT cage 2, secondary winding and iron core assembling 3, main insulation 4, EHT cage carriage 5, fiberglass insulating tube 6, high pressure electric screen 7, middle electric screen 8, electric screen 9, silicon rubber full skirt 10, chassis overhang 11, secondary connection box 12, fairlead carriage 13, secondary lead wires pipe 14 and insulation filling resin 15 etc. form.One time winding 1 can adopt excellence conductors such as copper rod, copper pipe, copper bar to make, and it passes from the centre bore of secondary winding and iron core assembling 3, and is fixed on the EHT cage 2 end and 2 electric connections of EHT cage, other end electric insulation.Secondary winding and iron core assembling 3 are firmly welded with secondary lead wires pipe 14, and its surface coats with semiconductive material, and makes smooth treatment, and this surface promptly is a ground electric screen 9.Ground electric screen 9 external solid insulating material are successively made main insulation 4 on secondary winding and iron core assembling 3 and secondary lead wires pipe 14, and when the pre-designed number of plies, lay with the middle electric screen 8 that conducts electricity or semiconductive film is made, these electric screens stagger gradually along the position of short transverse, and length shortens from inside to outside successively.The last layer electric screen (high pressure electric screen 7) all coats the main insulation of twining on the secondary winding, and carries out equipotential with winding 1 a usefulness wire and connect.

Silicon rubber full skirt 10 is bonded on the fiberglass insulating tube 6, and glued joint the lower end of fiberglass insulating tube 6 metal flange, is used for fixing the chassis overhang 11 that instrument transformer is installed usefulness.Glued joint the upper end of fiberglass insulating tube 6 EHT cage carriage 5, and it is used for fixing EHT cage 2.Secondary winding and iron core assembling 3 is fixed in the fiberglass insulating tube 6 by fairlead carriage 13 together with the main insulation 4 that holds on them with secondary lead wires pipe 14, and the excess room 15 perfusion insulating resins in the cavity that is made of EHT cage 2, EHT cage carriage 5, fiberglass insulating tube 6, fairlead carriage 13 etc. are filled.Connection seam between Primary Conductor 1, EHT cage 2, EHT cage carriage 5, fiberglass insulating tube 6, the fairlead carriage 13 seals with fluid sealant.

Further improve as of the present utility model, middle electric screen 8 not only surrounds secondary lead wires pipe 14 positions, but extends upward, and secondary winding 3 is encased (as shown in Figure 2).After adopting this structure, make that the Electric Field Distribution in the main insulation of wrapping up secondary winding is more even, be particularly suitable for the superhigh pressure dry-type current transformer, help reducing main insulation thickness.

Further improve as of the present utility model, secondary lead wires pipe 14 can be made toroidal, up-small and down-big (as shown in Figure 2).After adopting this structure, secondary lead wires pipe 14 has held main insulation 4 backs, and diameter is roughly suitable up and down, is approximately cylindrical, helps reducing the consumption of insulation filling resin 15.

The utility model is not limited to above-mentioned execution mode; no matter on its shape or structure, do any variation; every secondary winding is placed the instrument transformer head; and make main insulation with solid insulating material, pour into the Dry Type High Tension Current Transformer that the excess room in the curable insulating resin filling glass steel insulated tube 6 constitute and all drop within the utility model protection range.In addition; fiberglass insulating tube and silicon rubber full skirt are replaced with high tension insulator material or other material, perhaps full skirt are changed into same diameter or other shape, perhaps change the shape of EHT cage and carriage thereof; all be a kind of distortion of the present utility model, all think within the utility model protection range.

Claims (7)

1. Dry Type High Tension Current Transformer, it by winding 1, secondary winding and an iron core assembling 3, main insulation 4, fiberglass insulating tube 6, high pressure electric screen 7, middle electric screen 8, electric screen 9, silicon rubber full skirt 10, secondary lead wires pipe 14 and insulation filling resin 15 etc. form.It is characterized in that: secondary winding and iron core assembling 3 place the instrument transformer head, the main insulation 4 that the parcel solid insulating material is made on secondary winding and iron core assembling 3 and the secondary lead wires pipe 14, the ground electric screen 9, middle electric screen 8 and the high pressure electric screen 7 that have length and position to gradually change in the main insulation 4, the equal laminated structure of they common formation capacitor types, this structure is fixed in the fiberglass insulating tube 6, the curable insulating resin 15 of excess room perfusion in the fiberglass insulating tube 6 is filled, the fiberglass insulating tube 6 outer silicon rubber full skirts 10 of installing.

2. Dry Type High Tension Current Transformer as claimed in claim 1, it is characterized in that: parcel secondary winding and iron core are assembled the main insulation of 3 parts and are had only high pressure electric screen 7 and ground electric screen 9, electric screen 8 in the middle of also having except that high pressure electric screen 7 and ground electric screen 9 in the main insulation of parcel secondary lead wires pipe 14 parts.

3. as claim 1 and the described Dry Type High Tension Current Transformer of claim 2, it is characterized in that: secondary lead wires pipe 14 is toroidal, and is up-small and down-big.

4. Dry Type High Tension Current Transformer as claimed in claim 1 is characterized in that: parcel secondary winding and iron core are assembled in the main insulation of 3 parts also has middle electric screen 8 except that high pressure electric screen 7 and ground electric screen 9 are.

5. as claim 1 and the described Dry Type High Tension Current Transformer of claim 4, it is characterized in that: secondary lead wires pipe 14 is toroidal, and is up-small and down-big.

6. as claim 1 and the described Dry Type High Tension Current Transformer of claim 2, it is characterized in that: insulation filling resin 15 is silicon rubber.

7. as claim 1 and the described Dry Type High Tension Current Transformer of claim 4, it is characterized in that: insulation filling resin 15 is silicon rubber.