JPS602061A - Manufacturing method of insulated coil - Google Patents

Abstract

PURPOSE:To strengthen the insulating withstand strength of an insulated coil by mixing and heating cyclic-epoxide epoxy resin of low viscosity, p-t-butylphenolglycidyl ether, and phenol resin, mixing with zinc octylate, heating the mixture and adding cyclic acid anhydride. CONSTITUTION:0.1-10pts.wt. of phenol resin represented by the formula (II) (where n=200-1,000) is mixed with 100pts.wt. of composition which contains 100pts.wt. of cyclic-epoxide epoxy resin as a low viscosity epoxy-contained resin, and 5-50pts.wt. of p-t-butylphenolglycidyl ether represented by the formula ( I ). Then, 0.01-1.0pts.wt. of zinc octylate is mixed with 100pts.wt. of the mixture which is heated and averaged, the mixture is heated at 90-150 deg.C for 10- 120min., liquid cyclic acid anhydride is then mixed to obtain immersing resin. The resin is used as the insulation or the coil. In this manner, the insulated coil having less stimulus to the skin in low viscosity with excellent workability and high insulating withstand strength can be manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing an insulated coil using a novel low viscosity epoxy impregnated resin. For more details, please refer to the manufacturing method of insulated coils suitable for high-voltage rotating machines such as turbine generators and water turbine generators.In turbine generators and water turbine generators, the capacity of each unit increases as the demand for electricity increases. Along with this, there has been a growing tendency to increase the working voltage, and recently, devices with working voltages as high as 30 kV have appeared.

Due to the above-mentioned increase in working voltage, insulated coils are required to have stricter performance in many aspects, such as heat cycle resistance against repeated starting and stopping, heat resistance against temperature rises, and mechanical properties against vibrations and short circuits. It is becoming. Insulated coils built into rotating machines are generally used in a gas phase, but under high voltage, corona discharge occurs due to air breakdown of the gas existing in the coil, and there is a risk that the insulating layer of the coil will be destroyed. Therefore, as the insulating material, insulating sheets (including tape-shaped ones, hereinafter the same) using mica groups, which have excellent heat resistance, corona resistance, voltage resistance, etc., have been used for a long time.

The mica base is made of peeled mica base, which is made up of flakes obtained by thinly peeling mica raw ore, and the remaining mica base or peeled mica base is processed by a calcination method, water jet method, etc. to form fine flakes. There is also a composite mica group that is formed into a sheet by making paper.

All insulation sheets are backed by porous insulation materials such as paper, film, glass cloth, and polyester nonwoven fabric.
This is laminated with a mica-based thermosetting resin, usually in an amount of 6 to 20% (by weight, hereinafter the same).

A typical insulated coil is made by winding the above-mentioned insulating sheet over a coil conductor made by combining type 1 strands with appropriate insulation coating and forming them into a predetermined shape, and impregnating the wound layer with epoxy-impregnated resin. However, many conventional epoxy impregnated resins have high viscosity at room temperature, so they do not have good impregnation properties into the insulating sheet layer after winding the insulating sheet, causing poor impregnation. It causes deterioration of electrical and thermal characteristics.

Adding a diluent is a common method to overcome the disadvantage of the high viscosity of the epoxy-impregnated resin at room temperature, but the usual diluent is highly irritating to the skin and There are many things that deteriorate the electrical properties and thermal properties of the resin, and there is a disadvantage that if a diluent is used, the properties of the impregnated resin tend not to be changed sufficiently.

Furthermore, since epoxy-impregnated resins contain conventional epoxy curing catalysts, they also generally have a short pot life.

The inventors of the present invention have conducted extensive research in order to overcome the drawbacks of epoxy-impregnated resins, and as a result, they have wound an insulating sheet with a porous insulating material as a backing material on a fill conductor, and have applied a low viscosity layer to the wound layer. In the method of manufacturing an insulating coil having an insulating layer impregnated with an epoxy-impregnated resin and molded under heat and pressure, the low-viscosity epoxy-impregnated resin is a cyclic epoxide-type epoxy resin (hereinafter referred to as A composition prepared by blending 100 parts (by weight, the same applies hereinafter) of a cyclo-based epoxy resin with 5 to 50 parts of pt-butylphenyl glycidyl ether (hereinafter referred to as BPGE) represented by formula (I). (Hereinafter referred to as composition) 100 parts of formula (■)
: A composition containing 0.1 to 10 parts of noxy resin and heating it uniformly (hereinafter referred to as B composition) A composition containing 0.01 to 1.0 parts of octyl city zinc to 100 parts of 90 to 1500a
By using an impregnating resin produced by heat-treating the resin for 10 to 120 minutes and then blending liquid anhydride, the various drawbacks of the conventionally used epoxy-impregnated open side can be overcome. They discovered this and completed the present invention.

That is, in the present invention, composition B is prepared by blending 0.1 to 10 parts of phenoxy resin to 100 parts of composition A and heating it uniformly, and further adding octyl zinc skin o1 to 1 to 100 parts of composition B. 0 parts, 90-150
By adding a liquid cyclic acid anhydride after heat treatment at °C for 10 to 120 minutes, an epoxy-impregnated resin with a long pot life can be obtained. The epoxy-impregnated resin has almost no skin irritation and has a low viscosity that allows it to be impregnated into insulated coils at room temperature without causing poor impregnation, and the insulation film manufactured using the epoxy-impregnated resin has a high initial breakdown current IF. This has the remarkable effect of having stable electrical characteristics with little thermal deterioration. Furthermore, by using 0.1 to 10 parts of phenoxy resin per 100 parts of the composition as a component of the epoxy impregnated resin,
The effect of improving the adhesiveness and flexibility of the epoxy-impregnated resin can be obtained.

As the cyclo-epoxy resin having at least two epoxy groups in the molecule used in the present invention, halo, 4-epoxycyclohexylmethyl-3',4'-epoxycyclohexane carboxylate (Tisonox 221 manufactured by Chisso ■, Chisonox 221 manufactured by Ciba Geigy) ay-179, etc.), 6.
4-Epoxy-6-methylcyclohexylmethyl-3'
, 4'-epoxy-6'-methylcyclohexanecarboxylate, vinylcyclohexene dioxide (Chinnox 206 manufactured by Chisso ■), dicyclopentadiene dioxide, dipentene dioxide, etc., and even if they are used alone, Often, two or more types may be used in combination.

It is preferable to use the cyclo-based epoxy resin alone, but other types of epoxy resins, such as bisphenol-type epoxy resin, glycidyl ester-type epoxy resin, or novolac-type epoxy resin, may be added to 100 parts of the cyclo-based epoxy resin. It may be added in an amount not exceeding 30 parts and used in place of the cycloepoxy resin.

Although BP()K represented by formula (I) used in the present invention is a diluent, it has low skin irritation and hardly deteriorates the electrical properties, mechanical properties, and other properties of the epoxy resin. B.P.
GI is about 5 to 100 parts of the cyclo-epoxy resin.
It is preferable to use 50 parts; if the amount used is less than about 5 parts, the viscosity of the epoxy resin cannot be sufficiently lowered, and if it exceeds about 50 parts, properties of the cured product such as heat loss will deteriorate.

The phenoxy resin represented by formula (II) used in the present invention is blended for the purpose of improving the adhesiveness of the impregnated resin and improving the flexibility of the impregnated resin. The blending amount thereof is preferably in the range of about 0.1 to 10 parts per 100 parts of the composition consisting of 100 parts of the cyclo-epoxy resin and about 5 to 50 parts of BPGE. Impregnating resins with a blending amount of less than about 0.1 part will not improve adhesion or flexibility, while blending with a blending amount of more than about 10 parts will cause an increase in viscosity and pot life. Both are undesirable.

Approximately 0.1 to 1 o of phenoxy resin per 100 parts of silk composition
The B composition can be changed by mixing the two parts and heating them uniformly.

Zinc octylate, which is a latent curing catalyst for the epoxy resin used in the present invention, works to lengthen the pot life of the epoxy impregnated resin by adding it to the composition B and then subjecting it to a specific treatment. The amount of zinc octylate to be added to 100 parts of Composition B is preferably about 0.01 to 1.0 parts. Approximately 90% of composition B containing zinc octylate
After heat treatment at ~15oC'a for 1o~120 minutes,
The pot life of the epoxy-impregnated resin prepared using the same is longer than that of the epoxy-impregnated resin prepared using the resin without heat treatment.

Although the cause of such an effect of heat treatment is not clear, it is thought that the pot life becomes longer because zinc octylate is added uniformly by heat treatment.

When the heating temperature is less than about 90'O
Heating for 0 to 120 minutes does not sufficiently extend the pot life of the epoxy-impregnated resin;
When it exceeds 00, zinc octylate acts as an epoxy resin curing catalyst, and the pot life is conversely shortened.

Furthermore, if the amount of zinc octylate in Composition B is less than about 0.01 part, the pot life of the resulting epoxy-impregnated resin will not be sufficiently long even if the heat treatment is performed. Even if the epoxy impregnated resin exceeds 10%, problems such as the pot life of the epoxy impregnated resin being shorter than the required period as an impregnated resin occur.

An epoxy-impregnated resin is prepared by blending a liquid cyclic acid anhydride with a predetermined heat-treated B composition.

Liquid cyclic acid anhydrides used in the present invention include hexahydrophthalic anhydride, methylhexahydrophthalic anhydride (Decoy-5500 from Hitachi Chemical HJJI!, etc.),
Methyltetrahydrophthalic anhydride (such as HN-2200 manufactured by Hitachi Chemical ■ and QJ (-200 manufactured by Nippon Zeon ■)) or methylendomethylenetetrahydrophthalic anhydride (such as methylhimic anhydride manufactured by Hitachi Chemical ■) ), etc., and they may be used alone, and 2
More than one species may be mixed and used.

The amount of the cyclic acid anhydride to be blended is not particularly limited as long as it is a commonly used amount.

The insulated coil manufactured by the method of the present invention consists of winding an insulating sheet manufactured by a conventional method on a coil conductor,
The wound layer is impregnated with the epoxy impregnated resin used in the present invention under vacuum and pressure under normal conditions, and then inserted into a mold and molded under heat and pressure. The molding conditions include a heating temperature of about 100 to 25 octl.

Pressure: Approximately 5-100 m2, heating time: approximately 4-2
By molding using the epoxy impregnated resin under such conditions, the initial breakdown voltage of the manufactured insulating film, which does not cause poor impregnation, is 1 to 1.5 hours compared to the conventional method. The insulation film is 60% more expensive and has stable electrical properties with less thermal deterioration. If the above-mentioned molding conditions are exceeded, the interlayer adhesion of the insulating film decreases, and as a result, peeling or flaking occurs due to heating, etc., and the electrical properties deteriorate significantly due to heating, which is not preferable.

Next, the method of the present invention will be explained in more detail based on Examples, but the present invention is not limited to these Examples.

Example 1 85 parts of ay-179 as a cyclo-based epoxy resin, B
Mix 15 parts of PGE and 0.2 parts of phenoxy resin (PKHH manufactured by Union Carbide) and heat at 120°
After heating for a uniform time, 0.1 part of zinc octylate was added and further heat treated at 120 c'CJ for 60 minutes. After cooling to 25°0, a low-viscosity epoxy-impregnated resin (hereinafter referred to as resin A) was prepared by blending 99.6 parts of HN-2200 as a liquid cyclic acid anhydride.

The initial viscosity, pot life and adhesive strength of Resin A thus prepared were measured. The results are shown in Table 1.

The initial viscosity was measured using a B-type viscometer at 25°0, and the pot life was determined by storing resin A in a constant temperature and humidity chamber at a temperature of 25°0 and humidity of 35%, and measuring the viscosity every week. The number of days it takes for the viscosity at 25°O to reach 500cP (if it exceeds it, it becomes difficult to completely impregnate the insulated coil), and the adhesive strength is measured using the helical coil method based on J-Tech 502106. It is.

Next, 2mm width x 5mm height x 2000mm length
40mm heavy glass-wrapped rectangular copper wire combined in 2 rows and 20 tiers
Glass cloth (
A laminated mica tape (manufactured by Arisawa Seisakusho ■, thickness 0-025 mm) as the backing material was wound 10 times in a half-overlap manner, and Tetoron tape (manufactured by Hotarin ■, thickness 0.15 mm) was further wound as a protective insulating layer. is wound once, and resin A is applied to it at a pressure of 0.
Vacuum impregnation was carried out for 180 minutes at a pressure of 1 mm Hp or less, and then pressurized for 180 minutes at a pressure of 6 kg/am2, and then inserted into a mold and heat-press molded at a temperature of 155 °0 and a pressure of 20 at 97 parts m2 for 12 hours to form the insulating layer. An insulated coil with a thickness of 5.0 mm was obtained.

Using the obtained insulation fill, c 1s kv-i, skv
The difference in dielectric loss tangent (△tanδ) between the initial one and 20
The initial breakdown voltage in silicone oil was measured for both species after thermal aging at 0°O for 16 days and at a constant pressure increase rate of i kV/sec. The results are shown in Table 2.

Example 2 60 parts of ay-179 as a cyclo-based epoxy resin, B
14 by mixing 40 parts of PGI and 2 parts of phenoxy resin.
After uniform heating at 0°'a for 2 hours, 0.2 parts of zinc octylate was added and further heat-treated at 140°0 for 60 minutes. After cooling to 25°0, 100 parts of HH-5500 as a liquid cyclic acid anhydride was added to prepare a low-viscosity epoxy-impregnated resin. Each characteristic thereof was measured in the same manner as in Example 1. The results are shown in Table 1.

In addition, an insulated coil was manufactured in the same manner as in Example 1, and
The Δtanδ and initial breakdown voltage of the species were measured. The results are shown in Table 2.

Examples 6-5 80 parts of ax-179 as a cyclo-epoxy resin, 1
After mixing 20 parts of 3PGK and 0.5 part of phenoxy resin and homogenizing by heating at 100°O for 2 hours, 0.6 parts of zinc octylate was added and the mixture was heated at 100°C, 1160°a, and 14500°C for 30 minutes. Insulating films were manufactured and various properties were measured in the same manner as in Example 1, except that six types of low-viscosity epoxy-impregnated resins were prepared by heat treatment. The results are shown in Tables 1 and 2.

Comparative Example 1 40 parts of CY-179 as a cyclo-based epoxy resin, B
Mix 60 parts of PGFt and 5 parts of phenoxy resin and make 1
After uniform heating at 20% for 2 hours, 1.5 parts of zinc octylate was added and further heat treated at 120% for 60 minutes.

After cooling to 25°0, 85.5 parts of HN-2200 as a liquid cyclic acid anhydride was added to prepare an impregnated resin. Example 1 of various characteristics about it
It was measured in the same manner. The results are shown in Table 1.

Further, an insulated coil was manufactured in the same manner as in Example 1, and its characteristics were also measured. The results are shown in Table 2. As is clear from these, the pot life is 14 days and the viscosity is 500.
It was extremely bad, exceeding cP.

On the surface of the obtained insulated coil, peeling was observed in some places, and both Δtan δ and initial breakdown voltage were very poor.

Comparative Example 2 An impregnated resin was prepared in the same manner as in Example 1, except that the heat treatment conditions were changed to 120° 0 for 60 minutes and 80° 0 for 60 minutes in Example 1, and an insulated coil was manufactured. Various characteristics were measured for each. The results are shown in Tables 1 and 2.

Because the heat treatment temperature is low, zinc octylate is not added uniformly, and the pot life of the impregnated resin is 60 days, with a viscosity of 50.
The adhesive strength exceeded 0 aP, the adhesive strength was low, and the insulating film caused poor curing, resulting in very poor Δtan δ and initial breakdown voltage.

Comparative Example 6 100 parts of Epicoat 828 (bispheno-) vA type epoxy resin, manufactured by Yuka Shell Co., Ltd., trade name), imidazole (trade name 2E4MZ, Shikoku Kasei Kogyo (11 parts) as a catalyst)
) and 0.1 part of HN-2200 as an acid anhydride.
An impregnated resin was prepared by mixing 66 parts, but its initial viscosity was 25
% already showed 700 cP, making it unsuitable as a room temperature epoxy impregnated resin. Further, when an insulated coil was manufactured in the same manner as in Example 1, the initial viscosity was high, resulting in poor impregnation, and both Δtan δ and breakdown voltage were very poor. The measurement results are shown in Tables 1 and 2.

As described above, the insulated coil manufactured by the method of the present invention uses a new low-viscosity epoxy-impregnated resin, and has excellent electrical and thermal properties for use in high-voltage rotating machines, and has extremely high industrial value. It is something.

Table 1 Table 2 Procedural Amendment (Voluntary) Commissioner of the Patent Office 1.1'- Indication of Patent Application No. 1981-108171 2
, Title of invention: Method for manufacturing insulated coil; 3. To the person making the amendment Representative Hitoshi Katayama Part 5, Subject of amendment (1) Column 6 of “Detailed Description of the Invention” of the specification, Contents of amendment (1) “Alignment J” on page 11, line 18 of the specification Correct it as “adverse effect”.

(2) Correct r 1skV -1,5kvJ in line 4 of page 15 to f-5kV/mm -0,5kV/mn J.

that's all

Claims (4)

[Claims] (1) A method for manufacturing an insulated coil having an insulating layer in which an insulating sheet with a porous insulating material as a backing material is wound around a coil conductor, the wound layer is impregnated with a low-viscosity epoxy-impregnated resin, and the insulating layer is formed under heat and pressure. , 100 parts by weight of a composition obtained by blending 100 parts by weight of a cyclic epoxide type epoxy resin and 5 to 50 parts by weight of pt-butylphenyl glycidyl ether represented by formula (1) as the low-viscosity epoxy-impregnated resin. 0.01 parts by weight of zinc octylate per 100 parts by weight of a composition prepared by blending 0.1 to 10 parts by weight of a phenoxy resin represented by the formula (■): (in the formula, n is 200 to 1000) and homogenizing by heating. ~1
．． 0 parts by weight and 10 to 120 parts at 90 to 150°O.
A method for producing an insulating film characterized by using an impregnated resin produced by heat-treating for a minute and then blending a liquid cyclic acid anhydride. (2) Cyclic epoxide type epoxy resin, 4-epoxycyclohexylmethyl-51,41-epoxycyclohexanecarboxylate, 3,4-epoxy-6
-Methylshift tetrahexylmethyl-37,4/-epoxy-6'-methylcyclohexane carboxylate, vinylcyclohexene dioxide, dicyclopentadiene dioxide, and dipentene dioxide; one or more selected from the group consisting of The manufacturing method according to claim (1) is used. (3) Hexahydro7/I as a liquid cyclic acid anhydride
/anhydride, methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, and methylendomethylenetetrahydrophthalic anhydride, and methylendomethylenetetrahydrophthalic anhydride. (1
) The manufacturing method described in section. (4) Extinction coil molding conditions are heating temperature 100-250
cυ, pressure 5 to 100 kq/am2, heating time 4
The manufacturing method according to claim (1), wherein the manufacturing time is 24 hours.