KR20020006008A - transformer excellenceing electric isolation and plastic operation method thereof - Google Patents

Abstract

PURPOSE: A combined voltage current transformer having excellent electric insulation and a forming method thereof are provided to enhance electric insulation by forming an insulation layer using fire-resistant/self-extinguishing synthetic resin, as well as be miniaturized and lightened by combining a current transformer and a voltage transformer. CONSTITUTION: A fixed plate(6) is mounted on a bottom, two I/O terminals are fixed to a top surface, and a primary winding of a transformer consists of single wire. A transformer core(43) consists of a core type wound core to be vertically positioned. Terminal stands(51,52) are fixed to both sides of a bottom of a body(9). A neutral terminal is attached to a rear bottom part of the transformer. A partition(21) is formed between top I/O terminals of the transformer and a cover(22) is covered over the partition(21) to be fastened by screws(23).

Description

Transformer current transformer with excellent electrical insulation and its molding method {transformer excellenceing electric isolation and plastic operation method

The present invention relates to a molded article and a method of molding the molded transformer and the instrument current transformer which is used to measure the amount of power during power supply into a single article using a flame-retardant, non-flammable synthetic resin. More specifically, it consists of one primary winding of the transformer, and the inner iron core is perpendicular to the winding in the vertical direction to form a transformer and a current transformer into a single item, bringing small size and light weight, and reducing production cost. The present invention relates to a transformer, a current transformer, and a molding method having excellent electrical insulation by injecting an insulating layer using a flame retardant and nonflammable synthetic resin at a constant temperature and a constant pressure.

1 is a perspective view of a transformer, a current transformer for power supply and instrumentation of the Republic of Korea Utility Model Registration Publication No. 95-4416 published before the present application to both sides of the bottom surface of the rectangular lower body (3 ') of the upper part is made of steel The upper surface of the fixed plate (1 ') bent in the' c 'shape is fixed, and the terminal box (2') provided with a plurality of secondary terminal block (21 ') is connected to the household meter and the wire to facilitate the connection with the pipe. It is formed and installed in the front bottom of the lower body (3 ') and there is installed a transformer (4') for converting the high voltage transmitted through the power transmission line into a commercial voltage therein.

After installing a current transformer 7 'that converts a high current into a low current in the upper body 6' provided with a plurality of primary terminals 5 'connected to the transmission line, the upper body 6' is mounted. It is coupled with the lower body (3 '). In addition, the transformer primary winding 41 'is divided into four, and the transformer iron core 43' is laterally symmetric in an outer shape.

In the primary winding 41 'of the transformer, the coil and the insulating paper form a plurality of layers, and have a dielectric strength by appropriately dividing a high voltage. The voltage dividing method divides the entire winding into four or so and forms a coil on the insulating paper for each layer. Repeat the winding to connect them in series.

However, this technology means that the fixed plate 1 'is installed on the upper side of the bottom surface, and the plurality of terminals 5' are fixed on the upper surface, and the current ratio is two types. 4 are used to change the current ratio (for example of double ratio: 600A-300A, 100A-50A, 10A-5A) Transformer primary winding (41 ') is divided into four, and the transformer core is of the outer iron type, A large number of secondary terminal blocks (21 ') are installed, and there is no indication of the neutral terminal of the instrument transformer, and the lack of a sealing device for the prevention of electricity prevents the transformer's external appearance from becoming large, heavy, and complicated. There is a problem that the cost rises, there was a problem that the electrical insulation is not excellent.

To solve the above problems

First, the fixed plate is installed on the bottom of the floor, and two input and output terminals are fixedly installed on the upper surface (the current ratio for the instrument is a single ratio (current ratio is constant (one)).

Second, the primary winding of the transformer as one set, the iron core is located up and down in the inner steel type, fixed by forming two left and right at the bottom of the body, the lower side of the rear of the transformer (transformation, general term of the transformer) The neutral terminal for grounding was installed in the instrument transformer so that it could not be used without neutral grounding in the instrument transformer.

Third, between the input and output terminals of the transformer is blocked, and the top is covered with a cover and then sealed with a sealing bolt on the top of the partition.

Fourthly, the winding of the high voltage side of the transformer is impregnated under vacuum while maintaining a constant temperature and pressure by using flame-retardant and non-flammable synthetic resin, or injection molding and curing is performed without impregnation to form a finished product or impregnation. The final product was molded in one process in the molding tank without any primary molding process.

1 is a cross-sectional view of a conventional transformer current transformer.

Figure 2 is a perspective view of a transformer, current transformer with excellent electrical insulation applied to the present invention.

Figure 3 is a front cross-sectional view of the transformer, current transformer with excellent electrical insulation applied to the present invention.

Figure 4 is a side cross-sectional view of a transformer, current transformer with excellent electrical insulation applied to the present invention.

<Description of Major Symbols in Drawing>

1: power input / output terminal 11: input terminal 12: output terminal

DESCRIPTION OF SYMBOLS 2: Anti-conductor 21: Space 22: Terminal cover 23: Sealing bolt

3: current transformer 31: current transformer primary winding 32: current transformer secondary winding

4: transformer 41: transformer primary winding 42: transformer iron core

5: secondary terminal 51: transformer secondary terminal 52: current transformer secondary terminal 53: secondary terminal box

6: fixing plate 7: transformer neutral terminal (for grounding) 8: ground terminal

9: synthetic resin body

Figure 2 is a transformer with excellent electrical insulation applied to the present invention, a perspective view of a current transformer, Figure 3 is a transformer with excellent electrical insulation applied to the present invention, a cross-sectional view of the current transformer, Figure 4 is a transformer with excellent electrical insulation applied to the present invention As a side cross-sectional view of the current transformer, the fixed plate 6 is installed at the bottom of the bottom as shown, and two input and output terminals are fixed transformer current transformers installed at the upper surface .

The primary winding 41 of the transformer 4 is made of one, the iron core 43 of the transformer 4 is located in the upper and lower sides of the inner steel type, the second to the left of the body 9, two by two The terminals 51 and 52 are molded and fixed, and a grounding neutral terminal 7 is attached to the lower side of the rear side of the transformer (transformer, current transformer generically) 3, 4. In addition, the instrument transformer (4) can not be used without the neutral ground.

The transformer is blocked between the input and output terminals of the upper end of the transformer and the upper end of the transformer is covered with a cover 22, and then the sealing 21 is tightened with a sealing bolt 23 on the partition 21. In addition, the device is sealed by preventing the operation of the conductive part in order to prevent the electric current transformer of the transformer. In addition, the secondary terminal box 53 is connected to a plurality of transformer current transformers are collected in one place.

The transformer is mainly installed in the switchgear installation panel, the width of the switchgear should be 1200mm to install the existing transformer, but in the case of the transformer applied to the present invention can be reduced to 900mm, the economical efficiency of the switchgear production due to the transformer as well as the space of the installation place It is easy to secure.

In addition, the width and weight of the transformer is conventionally 300mm and 60kg, but the width and weight of the transformer applied to the present invention is 180mm and 47kg, which is reduced in width and weight by 60% and 73% in comparison with the existing products, making it compact and lightweight. To make it possible.

In more detail, the transformer current transformer for power supply is formed with a partition 21 between the power input terminal 11 and the output terminal 12 located above to cover the upper main cover 22. Sealed with a sealing bolt (23) to connect the two terminals with a metal wire or metal rod, etc. so as not to be conductive.

In addition, while the structure of the conventional iron wire core applied to the wide side is wide on both sides, the iron core iron applied to the present invention is narrower than this. The iron-resistant iron core applied to the present invention has a vertical direction at right angles to the winding, so that it is easy to install in a limited space (male, switchboard, etc.), light weight, and reduce cost. In addition, it is made of winding core, so its own power loss is small, so it maintains high accuracy (ACCURACY) in weighing and measuring.

The transformation method of the transformer current transformer is formed by three methods, and the molding method is a step-by-step method in which an impregnation process, a finished product molding process, and a curing process are separately installed, followed by a primary molding process, and a final product molding process curing process. It is divided into two-step method of forming, single molding process and ONE STEP method of hardening process.

First, the stepwise method is to put the high voltage side winding of the transformer and the flame retardant and non-flammable synthetic resin into a mold of a certain type and preheat it to a temperature of 20 ° C. to 150 ° C., and then to a temperature of 20 ° C. to 100 ° C. and a vacuum of 20 mbar or less in an impregnation tank. After injection at 0.2kg / cm ² ~ 8.0kg / cm ² pressure was applied to the curing furnace to cure at a temperature of 50 ℃ ~ 150 ℃ and then assembled with a mold to form a finished product,

In the two-stage method, the high-voltage winding and the flame-retardant and non-flammable synthetic resin are put in a mold of a predetermined shape, preheated to a temperature of 20 ° C. to 150 ° C., and then injected in a vacuum bath at a temperature of 20 ° C. to 100 ° C. and a vacuum of 20 mbar or less. After applying pressure of 0.2kg / cm ² ~ 8.0kg / cm ² and curing at 50 ℃ ~ 150 ℃ in the curing furnace, the surface is sand blasted (primary process) and then assembled into mold After injection at 20 ℃ ~ 100 ℃ and vacuum at 20mbar or lower in the injection tank, the finished product is molded at the temperature of 50 ℃ ~ 150 ℃ in the curing furnace.

ONE STEP is a casting tank that maintains the temperature of 20 ℃ ~ 100 ℃ by pre-heating the transformer and current transformer to 20 ℃ ~ 150 ℃ without performing impregnation or primary preforming process. Transfer the preheated flame retardant and non-flammable synthetic resin at 20 ℃ ~ 150 ℃ under vacuum of 20mbar or less, apply 0.2kg / cm ^{2 to} 8.0kg / cm ² pressure, reduce the pressure to atmospheric pressure and transfer to the curing furnace. The finished product is molded in a curing furnace at a temperature of ˜150 ° C.

When the preheating temperature is 20 ° C. or less, the resin is difficult to penetrate the winding because the viscosity is high, and when it is 150 ° C. or more, hardening occurs and the resin hardens, so molding is difficult.

When the temperature of the impregnation tank is 20 ° C, impregnation is difficult because the viscosity of the resin is high, and when the temperature of the impregnation tank is 100 ° C or more, it is difficult to impregnate the resin.

If the curing temperature of the curing furnace is less than 50 ℃ hard to harden because the temperature is low, if the curing temperature is 150 ℃ or more there is a problem that the shrinkage occurs.

In addition, in order to make the penetration of the resin even easier, the resin is permeated while the pressure after vacuum is periodically repeated.

In addition, since the permeability of synthetic resin is sure inside the winding, it is possible to reduce the cost by the small size and light weight because it consists of only one winding without dividing the voltage into about 4 parts.

Among the molding methods, the step forming method consists of impregnation process and finished product forming process, which makes the process cumbersome and costly.In the two-step molding method, the finished product is molded after the primary injection process. Since the insulation is destroyed due to the occurrence of, the final product is formed after the primary molding with low viscosity synthetic resin to compensate for this, and the thermal expansion rate of the pre- and post-process is different so that these interfaces can be relaxed by temperature change. Therefore, there is a problem that the insulation can be destroyed after aging. ONE STEP, which does not perform impregnation process or primary injection process, forms the finished product at a temperature of 50 ℃ ~ 150 ℃ regardless of process by appropriate pressure control of the injection tank and maintenance of proper temperature. The device produced by the single molding process can be miniaturized without the need for impregnation or primary molding, and does not create an unnecessary insulation space, thereby reducing the weight of the device and having excellent electrical properties due to the good penetration of synthetic resin. Becomes Therefore, the single molding method is most preferred, and molding is carried out in a step method and a two step method according to the characteristics of the product.

As described above, the present invention improves the electrical insulation of the device by molding the insulating layer by flame-retardant and non-flammable synthetic resin in a single molding method, and also the effect of small size and light weight by integrally molding the instrument transformer and the current transformer. In addition, manufacturing costs can be reduced by reducing the materials required.

Claims (4)

The fixing plate 6 is installed on the bottom of the bottom, two input and output terminals 11 and 12 are fixedly installed on the upper surface, and the primary winding 41 of the transformer 4 consists of one, and the transformer core ( 43) is made of iron core winding core located in the vertical direction, the terminal block (51, 52) is fixed to the left and right in the lower part of the body (9), transformer, grounding neutral terminal ( 7) is installed, and the partition 21 is formed between the upper input and output terminals of the transformer, current transformer, and covers the cover 22 on the upper part, and then tightened with a bolt 23 to seal excellent. Transformer current transformer. The high voltage side winding of the transformer and current transformer and the flame retardant and nonflammable synthetic resin were put into a mold of a certain type and preheated to a temperature of 20 ° C. to 150 ° C., and then transferred to an impregnation tank and injected under a vacuum of 20 ° C. to 100 ° C. and a vacuum of 20 mbar or less. After the pressure of 0.2kg / cm ² ~ 8.0kg / cm ² and reduced to the atmospheric pressure, and then moved to the curing furnace to cure at a temperature of 50 ℃ to 150 ℃ molding of the transformer with excellent electrical insulation, characterized in that the molding Way. After high voltage side winding of transformer and current transformer and flame-retardant and non-flammable synthetic resin are put in a mold, preheated to 20 ℃ ~ 150 ℃, and then injected at 20 ℃ ∼100 ℃ and vacuum below 20mbar in injection tank. 0.2kg / cm ² ~ 8.0kg / cm ² pressure is applied to the curing furnace at a temperature of 50 ℃ ~ 150 ℃, the surface is sand blasted (sand blast) and then assembled into a mold 20 ℃ in the injection tank A molding method for a transformer with excellent electrical insulation, characterized in that the curing is carried out at a temperature of ˜100 ° C. and a vacuum of 20 mbar or less, followed by curing at a temperature of 50 ° C. to 150 ° C. in a curing furnace. The high voltage side winding of the transformer and current transformer and the terminal, flame-retardant and non-flammable synthetic resin are put into the molding tank, preheated to 20 ℃ ~ 150 ℃ and injected under 20 ℃ ~ 100 ℃ and vacuum below 20mbar 0.2kg / cm ² A method of forming a transformer current transformer having excellent electrical insulation, characterized in that after applying a pressure of ˜8.0kg / cm ² , it is reduced to atmospheric pressure, and then moved to a curing tank to cure at a temperature of 50 ° C. to 150 ° C.