KR102149902B1 - Current transformer covering material, method for munufacturing current transformer covering material, method for covering current transformer using the same - Google Patents

Abstract

A method of manufacturing an instrument current transformer coating material is disclosed. A method for manufacturing an instrument current transformer coating material comprises: preparing an organic mixture by mixing an unsaturated resin, an adhesive material, an elastic material, a first antifoaming agent, a second antifoaming agent, a binder, and a hardener; Mixing first silicon oxide, second silicon oxide, aluminum hydroxide, and titanium dioxide having different sizes to prepare an inorganic mixture; And mixing the organic mixture and the inorganic mixture to prepare a current transformer coating material for an instrument.

Description

Covering material for instrument current transformer, manufacturing method thereof, and coating method of instrument current transformer using the same {CURRENT TRANSFORMER COVERING MATERIAL, METHOD FOR MUNUFACTURING CURRENT TRANSFORMER COVERING MATERIAL, METHOD FOR COVERING CURRENT TRANSFORMER USING THE SAME}

The present invention relates to an instrument current transformer, and more particularly, to a coating material for an instrument current transformer and a method of covering the instrument current transformer by using the coating material.

In general, there are single-type and transformer-mounted meters for power trading, and if the user's power consumption exceeds a certain capacity, the single-type watt-hour meter is large and cannot be installed and manufactured. Therefore, for users with a load current of 120A or more, a current transformer (current transformer) , Current Transformer; CT) is installed to reduce the current at a certain rate, and after integrating the current into the transformer part meter, the amount of consumption can be measured by multiplying the reduced rate by the usage guideline.

Current transformers for instrumentation are installed in a switch on a high-voltage line through which high-voltage electricity flows, or in a location for monitoring for high-voltage management and securing power for a management system, and are used in various fields such as lines, circuit breakers or transformers.

These current transformers are available in two types, which are divided into general current transformers and split current transformers. Since the general current transformers (e.g., ring type current transformers) are formed as one unit, when initially constructed on the line, first assemble the current transformers in the enclosure of the circuit breaker, the inside of the transformer, the busbars or cables of the switchboard, etc. The device is assembled so as to penetrate the center of the current transformer.

That is, since the general current transformer is integrally formed without a separate configuration, after the current transformer is first installed, the cable or the like passes through the through hole formed in the center, so it is used under the premise that there is no dismantling or expansion of the current transformer. Therefore, for general current transformers, if an accident occurs due to the user's negligence to operate, or if additional expansion of the current transformer occurs, the line is cut off, and the current transformer must be replaced after disassembling the cables assembled on the track. There is a problem that it is not easy.

1 is a perspective view of a conventional ring-type current transformer. The ring-type instrument current transformer 1 may include a main body 10, a through hole 14, and a plurality of current terminals 12 and 12a. The main body 10 is formed in a ring (cylindrical) shape having a predetermined diameter and thickness (88 mm x 44 mm). The primary load wire through hole 14 has an inner diameter of the main body 10 penetrated with a predetermined diameter (40 mm), and a sufficient space is provided for the primary load wire to pass through the through hole 14. The current terminals 12 and 12a are composed of a plurality (+ and-terminals) at one end of the outer periphery of the main body 10 so that the wires are wired, and the current terminals 12 and 12a are coupling means to which the wires are coupled, for example , Bolts or joints.

The outer surface of the ring-type instrument current transformer is covered by a cladding material, but in the case of the existing cladding material, the linear expansion coefficient is significantly different from that of the ring-type instrument current transformer, so there is a problem that the cladding material is damaged due to air bubbles and cracks in the cladding material due to temperature difference. have. In addition, when the covering material is damaged, electrical insulation breakdown occurs, leading to an explosion or fire.

Accordingly, the inventors of the present invention have come to develop a novel coating material capable of preventing damage to the coating material while having ductility by improving the existing coating material.

Registration Utility Model Registration No. 20-0471248 (Registration Date 2014.02.04.)

The technical problem to be solved by the present invention is to provide a covering material for an instrument current transformer and a method for manufacturing such a covering material, which has ductility and corresponds to the coefficient of thermal expansion of the instrument current transformer.

In addition, it is to provide a method of covering an instrument current transformer using an instrument current transformer coating material.

In order to solve the above technical problem, the method of manufacturing a current transformer coating material for an instrument according to an embodiment of the present invention is a mixture of an unsaturated resin, an adhesive material, an elastic material, a first defoaming agent, a second defoaming agent, a binder, and a hardener. Preparing an organic mixture; Mixing first silicon oxide, second silicon oxide, aluminum hydroxide, and titanium dioxide having different sizes to prepare an inorganic mixture; And mixing the organic mixture and the inorganic mixture to prepare a current transformer coating material for an instrument.

In one embodiment, the unsaturated resin is polyester, the adhesive material is a tere-Phthalic material, the elastic material is ethylene glycol, and the first antifoaming agent is It is a silicone-based polymer antifoaming agent, the second antifoaming agent is a second non-silicone-based polymer antifoaming agent, the binder is silane, and the curing agent may be a curing agent for unsaturated polyester resin.

The terephthalic material may be terephthalic acid or dimethyl terephthalate.

It is preferable to use the product name BYK-A501 produced by BYK-Chemie as the first antifoaming agent, and BYK-A505 produced by BYK-Chemie as the second antifoaming agent.

The curing agent is preferably MEKP (Methyl Ethyl Ketone Peroxide).

In one embodiment, the organic mixture includes 15g of polyester, 65.7g of adhesive material, 7.2g of elastic material, 0.3g of first antifoam, 0.3g of second antifoam, 2g of silane and 1g of hardener can do.

In one embodiment, the inorganic mixture may include 117 g of first silicon oxide (purity 99.9%), 18 g of second silicon oxide (purity 99.9%), 19 g of aluminum hydroxide, and 7 g of titanium dioxide.

In one embodiment, the size of the first silicon oxide is greater than 0.23 and less than or equal to 0.33 mm,

The size of the second silicon oxide may be greater than 0 and less than 0.23 mm.

A method of covering a current transformer for an instrument according to an embodiment of the present invention comprises the steps of: inserting the current transformer for the meter into a mold including a current transformer inserting unit which is made of a silicon material and can accommodate the current transformer for the meter; It may include the step of coating the instrument current transformer using the instrument current transformer coating material.

In one embodiment, the step of covering the instrument current transformer using the instrument current transformer coating material may be performed in a space between the instrument current transformer and the current transformer insertion part while the instrument current transformer and the current transformer insertion part are spaced apart. Introducing a coating material for the instrument current transformer; Removing air bubbles generated in the instrument current transformer coating material; And it may include the step of curing the current transformer coating material for the instrument.

The current transformer coating material for an instrument according to an embodiment of the present invention is 15 g of polyester, 65.7 g of adhesive material, 7.2 g of elastic material, 0.3 g of first antifoam, 0.3g of second antifoam, 2g of silane and 1g. An organic mixture containing a curing agent of; And an inorganic mixture comprising 117 g of first silicon oxide (purity 99.9%), 18 g of second silicon oxide (purity 99.9%), 19 g of aluminum hydroxide, and 7 g of titanium dioxide.

In one embodiment, the size of the first silicon oxide may be greater than 0.23 and less than 0.33 mm, and the size of the second silicon oxide may be greater than 0 and less than 0.23 mm.

The coating material according to the embodiment of the present invention as described above corresponds to the coefficient of thermal expansion of the instrument current transformer (CT), and has ductility, so it is possible to prevent cracks or bubbles from being generated in the coating material due to changes in external temperature. .

In addition, it is possible to prevent the occurrence of cracks or air bubbles in the covering material, thereby causing electrical insulation breakdown, causing a fire in the instrument current transformer or the instrument current transformer from exploding.

1 is a perspective view of a conventional ring-type current transformer.
2 is a flowchart illustrating a method of manufacturing a current transformer coating material for an instrument according to an embodiment of the present invention.
3 is a flow chart of a method for covering an instrument current transformer according to an embodiment of the present invention.
4A is a side cross-sectional view of a mold used to cover a current transformer for an instrument according to an embodiment of the present invention.
4B is a plan cross-sectional view of a mold used to cover a current transformer for an instrument according to an embodiment of the present invention.

Since the present invention can make various changes and have various embodiments, specific embodiments are illustrated in the drawings and will be described in detail in the detailed description. However, this is not intended to limit the present invention to a specific embodiment, it is to be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the present invention.

Hereinafter, a preferred embodiment according to the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals refer to the same elements.

2 is a flowchart illustrating a method of manufacturing a current transformer coating material for an instrument according to an embodiment of the present invention.

Referring to Figure 2, the method of manufacturing a current transformer coating material for an instrument according to an embodiment of the present invention comprises the steps of preparing an organic mixture (S120), preparing an inorganic mixture (S140), and mixing the organic mixture and the inorganic mixture. It may include step S160.

An organic mixture is prepared by mixing an unsaturated resin, an adhesive material, an elastic material, a first defoaming agent, a second defoaming agent, a binder, and a curing agent (S120).

For example, the unsaturated resin is polyester, the adhesive material is terephthalic (Tere-Phthalic) material, the elastic material is ethylene glycol, the first antifoaming agent is a first non-silicone polymer antifoaming agent, and the second The antifoaming agent may be a second non-silicone polymer antifoaming agent, the binder is silane, and the curing agent may be a curing agent for unsaturated polyester resin.

The binder is tri-methacryloxypropyltrimethoxysilane, and it is preferable to use the product name A-174.

Binder (silane coupling agent) is a chemical substance that has two different reactive groups, organic and inorganic, in the same molecule. 　Inorganic materials such as glass, metals, minerals, and organic materials such as organic polymers, coatings, and adhesives are different. It plays the role of a contact point in the middle for material bonding.

As an example, the organic mixture includes 15 g of polyester, 65.7 g of adhesive material, 7.2 g of elastic material, 0.3 g of first antifoam, 0.3g of second antifoam, 2g of silane and 1g of curing agent.

Next, first silicon oxide, second silicon oxide, aluminum hydroxide, and titanium dioxide having different sizes are mixed with each other to prepare an inorganic mixture (S140).

For example, the inorganic mixture contains 117 g of first silicon oxide (purity 99.9%), 18 g of second silicon oxide (purity 99.9%), 19 g of aluminum hydroxide, and 7 g of titanium dioxide.

For example, it is preferable that the size of the first silicon oxide is more than 0.23 and less than 0.33 mm, and the size of the second silicon oxide is more than 0 and less than 0.23 mm.

When curing the unsaturated polyester, it is preferable to use silicon oxide having a very small particle size and stable characteristics in order to maintain a double bond of carbon and improve electrical properties (eg, dielectric breakdown voltage, etc.) at the same time.

The inorganic mixture is mixed using a separate container from the organic mixture, and another container of the same type used for mixing the organic mixture may be used.

Next, the organic mixture and the inorganic mixture are mixed (S160). For example, the organic mixture and the inorganic mixture may be mixed using a hand mixer.

In particular, mixing the organic mixture and the inorganic mixture is performed by applying vibration under vacuum conditions, and the degree of vacuum is preferably 10 to 30 mmHg. Since the organic mixture and the inorganic mixture are mixed with each other while applying vibration under vibration conditions, air bubbles that may be generated through mixing can be completely removed.

In addition, it is preferable that the manufacturing process of the instrument current transformer coating material is carried out at room temperature. When it is carried out at room temperature, it is possible to minimize the shrinkage between the resin particles, and because the heat shrinkage is small, the dimensional cracks of the manufactured instrument current transformer coating material or the mechanical stress remaining inside can be minimized.

Through this process, a covering material for an instrument current transformer according to an embodiment of the present invention is manufactured.

3 is a flow chart of a method for covering an instrument current transformer according to an embodiment of the present invention, FIG. 4A is a side cross-sectional view of a mold used to cover an instrument current transformer according to an embodiment of the present invention, and FIG. 4B is an embodiment of the present invention. It is a top cross-sectional view of a mold used for covering the current transformer for an instrument according to.

3 to 4B, in the method of covering an instrument current transformer according to an embodiment of the present invention, the step of inserting the instrument current transformer into the current transformer insertion part (S220) and covering the instrument current transformer using the instrument current transformer coating material It may include a step (S240).

The current transformer insert is made of silicon, and the current transformer for an instrument can be accommodated inside. The current transformer insertion part has a space in which an instrument current transformer can be inserted.

The current transformer insertion part is included in the mold and may be disposed in close contact with the inner circumferential surface of the mold.

When an instrument current transformer is inserted into the current transformer insertion part, the instrument current transformer is coated using the instrument current transformer coating material according to an embodiment of the present invention.

For example, in the step of covering an instrument current transformer using an instrument current transformer covering material, the step of injecting the instrument current transformer coating material into the space between the instrument current transformer and the current transformer insertion unit while the instrument current transformer and the current transformer insert are separated from each other ( S242), removing air bubbles generated in the instrument current transformer coating material (S244), and curing the instrument current transformer coating material (S244).

With the current transformer for instrumentation and the current transformer insertion part separated, insert the instrument current transformer into the current transformer insertion part in order to insert the covering material for the instrument current transformer into the space between the instrument current transformer and the current transformer insertion part. Make sure that the current transformers for instrumentation are separated by a certain distance.

Next, an instrument current transformer coating material is put into the space between the current transformer for the instrument and the current transformer insert. To this end, an input space may be formed between the handle and the mold, and between the handle and the current transformer insertion part.

Next, air bubbles generated in the instrument current transformer coating material are removed.

For example, bubbles may be removed by applying vibration under vacuum conditions, and the degree of vacuum may be 10 to 30 mmHg.

After the air bubbles have been removed, and the instrument current transformer coating material is cured. Curing can be carried out at room temperature. When curing is completed, the instrument current transformer coated with the coating material is separated from the mold, polished, and inspected for defects.

Although the embodiments according to the present invention have been described above, these are merely exemplary, and those of ordinary skill in the art will understand that various modifications and equivalent ranges of embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention should be determined by the following claims.

Claims (9)

Polyester, terephthalic acid or dimethyl terephthalate, ethylene glycol, first non-silicone polymer antifoam, second non-silicone polymer antifoam, silane, curing agent for unsaturated polyester resin Mixing with each other to prepare an organic mixture;
Mixing first silicon oxide, second silicon oxide, aluminum hydroxide, and titanium dioxide having different sizes to prepare an inorganic mixture; And
Mixing the organic mixture and the inorganic mixture to prepare an instrument current transformer coating material.
delete The method of claim 1,
The covering material is
15 g of polyester, 65.7 g of terephthalic acid or dimethyl terephthalate, 7.2 g of ethylene glycol, 0.3 g of the first non-silicone polymer antifoam, 0.3 g of the second A method for producing an instrument current transformer coating material comprising a non-silicone polymer antifoaming agent, 2 g of silane and 1 g of a curing agent for an unsaturated polyester resin.
The method of claim 1,
The inorganic mixture,
A method for manufacturing an instrument current transformer coating material comprising 117 g of first silicon oxide (purity 99.9%), 18 g of second silicon oxide (purity 99.9%), 19 g of aluminum hydroxide and 7 g of titanium dioxide.
The method of claim 1,
The size of the first silicon oxide is greater than 0.23 and less than or equal to 0.33 mm,
The size of the second silicon oxide is more than 0 and less than 0.23mm, the method of manufacturing a current transformer coating material for instrumentation.
delete delete 15 g of polyester, 65.7 g of terephthalic acid or dimethyl terephthalate, 7.2 g of ethylene glycol, 0.3 g of the first non-silicone polymer antifoam, 0.3 g of the second An organic mixture comprising a non-silicone polymer antifoaming agent, 2 g of silane and 1 g of a curing agent for unsaturated polyester resin; And
An instrument current transformer coating material comprising an inorganic mixture comprising 117 g of first silicon oxide (purity 99.9%), 18 g of second silicon oxide (purity 99.9%), 19 g of aluminum hydroxide and 7 g of titanium dioxide.
The method of claim 8,
The size of the first silicon oxide is greater than 0.23 and less than or equal to 0.33 mm,
The size of the second silicon oxide is greater than 0 and less than 0.23 mm, instrument current transformer coating material.

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