JPS6113610A - Manufacture of insulated coil - Google Patents

Abstract

PURPOSE:To obtain an insulated coil having excellent electrostatic tangent-voltage characteristics by a method wherein an insulating sheet lined by a porous insulating material is wound around a coil conductor, and when they are molded under heat and pressure by impregnating epoxy resin, the prescribed quantity of allylepoxy compound, liquid annular acid anhydride and a compound having polymerizable double coupling is contained in the epoxy resin. CONSTITUTION:An insulating sheet is wound around a coil conductor, and epoxy resin is impregnated therein by applying pressure under vacuum. At that time, the temperature of heating is selected at 100-250 deg.C, the pressure to be applied is selected at 5-100kg/cm<2>, the period of time for heating is selected at 4-24hr, and an insulated coil is formed. According to this constitution, the epoxy impregnated resin is formed by adding 0.1-100pts.wt. of allylepoxy compound having an alkyl radical and an epoxy radical in a molecule as separately shown by a formula, 50-150pts.wt. of liquid annular acid anhydride, and 5-300pts.wt. of a compound having polymerizable double coupling to 100pts.wt. of a compound having at least two epoxy radicals in a molecule.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method of manufacturing an insulated coil using a novel epoxy impregnated resin. More specifically, the present invention relates to a method for manufacturing an insulated coil suitable for use in rotating machines that use high voltage, such as turbine generators and water turbine generators.

[Prior art]

For turbine generators, water turbine generators, etc.

As the demand for electric power increases, there is a growing tendency to increase the noise level of each unit and increase the operating voltage, and recently, even units with operating voltages as high as JOkV have appeared.

Due to this increase in working voltage, insulated coils are required to have stricter performance in many respects, such as heat cycle resistance against repeated starting and stopping, resistance to heat deterioration due to temperature rise, and resistance to vibrations and short circuits. The button looks like this.

Insulated coils built into rotating machines are generally placed 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 coil insulation layer will be destroyed. Therefore, insulating sheets (including tape-shaped ones, hereinafter the same) using mica foil, which has excellent heat resistance, corona resistance, voltage resistance, etc., have been used as an insulating material for a long time.

In a normal insulated coil, the above-mentioned insulating sheet is wound around a coil conductor formed into a predetermined shape, and this wound layer is impregnated with epoxy-impregnated resin to form an insulating layer. Many epoxy-impregnated resins have high viscosity at room temperature and often have short pot lives.

In order to lower the viscosity of resins, it is common to add diluents, but 1) Normal diluents are highly irritating to the skin, and many of them have severe deterioration of properties, making it difficult to obtain sufficient properties. It is.

[Summary of the invention]

In view of these current circumstances, the present inventors have conducted intensive research into a new epoxy-impregnated resin that has improved the above-mentioned drawbacks, and have arrived at the present invention.

That is, in the insulated coil of the present invention, an insulating sheet is wound around a coil conductor in the same manner as in the conventional coil conductor, and this wound layer is impregnated with a novel epoxy-impregnated resin and then heated and press-molded to form an insulating layer. However, as the above-mentioned novel epoxy-impregnated resin, one molecule of the epoxy compound represented by general formula (I) is calculated based on the weight part (hereinafter simply referred to as part) of an epoxy compound having at least one epoxy group in one molecule. An allyl epoxy compound having both an allyl group and an epoxy group (R is hydrogen, halogen, or a -valent organic group) 0, / ~ ioo parts, a liquid cyclic acid anhydride so ~ / 30 parts, and a polymerizable double It was discovered that by using an epoxy-impregnated resin composition containing 3 to 300 parts of a compound having a bond, it is possible to provide an insulating layer with low viscosity and a long pot life, and with good curing properties when forming an insulated coil. The invention was completed.

The characteristics of the present invention are that the viscosity of the impregnated resin is lowered by using a low-element and low-viscosity allyl epoxy compound, and the allyl epoxy compound has both an allyl group and an epoxy group in one molecule, so that the epoxy compound and the acid Its purpose is to intervene as a component that reacts with both the anhydride and vinyl monomer reaction systems to form a uniform network, thereby improving the properties of the cured product.

The method for manufacturing an insulated coil according to the present invention will be explained below. First, the epoxy compound that can be used in the present invention may be any compound having at least one epoxy group in one molecule.

For example, bisphenol A diglycidyl ether type DER-33x (trade name of Dow Corporation), Epicote g co-L (
Shell company product name), GY-25! f (Chipa Co., Ltd. product name), novolac type DEN-937 (Dow Co., Ltd. product name), and alicyclic type CY-/? De (trade name, Chipa Co., Ltd.), etc., and these can be used alone or in combination.

Examples of the allyl epoxy compounds of the general formula (I) that can be used in the present invention include co-allylphenyl glycidyl ether, d-allylphenyl glycidyl ether,
Corey router methyl phenyl glycidyl ether,
-One allele=! -Methylphenylglycidyl ether, etc. In general formula (I), R is hydrogen, halogen, or -
Valid organic groups 1, e.g. alkyl groups e.g. -CHs, -C
For example, sHz.

Furthermore, examples of liquid cyclic acid anhydrides that can be used in the present invention include methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, and methylendomethylene hexahydrophthalic anhydride.

Furthermore, compounds having a polymerizable double bond that can be used in the present invention include styrene, vinyltoluene, divinylbenzene, diacrylates, dimethacrylates, trimethylolpropane triacrylate, trihydroxyethyl isocyanurate triacrylate, Examples include trihydroxyethyl isocyanurate trimethacrylate, triallyl trimellitate, and triallyl isocyanurate, and these can be used alone or in combination.

The amount of the allyl epoxy compound used in the present invention is desirably 7 to 10 parts per 100 parts of the epoxy compound. If the blending amount is less than 0.7 parts, the cross-linking between the epoxy component and the vinyl component will not be sufficient and no effect will be shown, and if it exceeds 700 parts, the independent properties of the allyl epoxy compound will become significant. , leading to a decrease in the properties of the impregnated resin (deterioration in mechanical strength, deterioration in electrical properties).

The amount of liquid cyclic acid anhydride used in the present invention is:
It is desirable to use SO to 730 parts per 100 parts of the epoxy compound. If the blending amount is out of this range, the bridging between the epoxy component and the acid anhydride component will not be sufficient, and the thermal deformation mudness and mechanical and electrical properties will decrease, both of which are unfavorable.

Moreover, a compound having a monopolymerizable bond is an epoxy compound lO
It is desirable that the amount is in the range of 3° to 3θθ parts to θ parts. If the blending amount is less than the S part, the effects of adding the vinyl compound (lower viscosity, etc.) cannot be obtained, and if it exceeds the SOO part, the shrinkage rate becomes too large and the properties as an impregnated resin deteriorate.

Furthermore, from the point of view of imparting flexibility to the impregnated resin, the effect of phenomena resin is large and one molecule - kklo, 000 ~ θ, O
70 parts of phenolic resin of θθ can be added within a range that does not cause shrinkage. If it exceeds 70 parts, the viscosity increases too much and cannot withstand use.

For the purpose of promoting the reaction of the immersion resin according to the present invention.

Addition of catalyst is effective. Reverse of epoxy compound
) Catalysts that promote the reaction include organic metal salts such as cobalt acetylacetonate and zinc actylate.

Examples include imidazoles, Lewis acids such as BFJ, and BCLs. Furthermore, as a vinyl polymerization initiation catalyst, peroxides such as dicumyl peroxide and benzoyl peroxide, azobisisobutyronitrile, etc. can be used to accelerate curing.

The insulated coil of the present invention is produced by winding an insulating sheet around a coil conductor, impregnating this wound layer with the novel epoxy impregnated resin shown above under vacuum pressure under known conditions, inserting it into a mold, and applying heat. The insulated coil is manufactured by pressure forming.

As for the molding conditions.

Heating temperature: 10θ~, 2jθ℃, pressure: lθθ,
The heating time t~kohiro time is adopted, thereby electrically,
6. If the molding conditions for obtaining an insulated coil with excellent thermal properties are out of the above range, the interlayer adhesion of the resulting insulated coil will be weak, resulting in a significant decrease in electrical properties during thermal deterioration.
Moreover, only floating and peeling occur in the insulating layer, which is undesirable.

(Za) According to the present invention, the electrical properties, especially the dielectric loss tangent-voltage characteristics (hereinafter simply referred to as ΔΔδ) K
It has become possible to manufacture superior insulated coils.

[Embodiments of the invention]

The method for manufacturing an insulated coil of the present invention will be described in detail below with reference to Examples and Comparative Examples.

Example l Epicoat ear (ex) is used as an epoxy compound.

20 parts of co-allylphenyl glycidyl ether, 20 parts of trimethylolpropane triacrylate, 20 parts of styrene aO based on 0 parts of J (trade name).

Add 10 parts of methyltetrahydrophthalic anhydride and dicumyl peroxide as a catalyst (0.0, t part 1)
．． t Zinc cutylate Zinc+170.7% was added to obtain an epoxy-impregnated resin. The initial viscosity of this impregnated resin was set to 5 at 2S°C.
It was Ocps (Centiboise).

Next, a 4IOX10. Glass cloth (manufactured by Arisawa Seisakusho, thickness θ,
θko1. ．． ) is used as a backing material, and a laminated mica tape is wound 71 times in a half-overlapping manner, and Tetron tape (manufactured in large quantities, thickness θtJm) is further wound once as a protective layer.
Pressure e, /mHt with the epoxy-impregnated resin obtained above
Vacuum impregnation was carried out for 110 minutes, then pressurized at a pressure of 3υ for 110 minutes, and then inserted into a mold and heated and pressure molded at a temperature of 133°C and a pressure car for 1 hour and 6 hours. Polymerization was carried out at iso° C. for 76 hours to obtain an insulated coil. The initial Δ hard δ and breakdown voltage of this insulated coil, and the Δ−δ after 16 days at tto°C were measured. These results are shown in Table 1.

The pot life (pot life) of the above-mentioned impregnated resin was tracked by leaving the resin in a constant temperature and humidity bath at a temperature of 5° C. and a relative humidity of 35%, and measuring the viscosity.

Measurements of viscosity are usually carried out at -weekly intervals, and 2! It is expressed as the number of days until the viscosity at r°C reaches IIo o cps.

If the viscosity is higher than II 00 cps, it becomes difficult to completely impregnate the insulated coil, which is not preferable.

As a result, the viscosity of the above-mentioned impregnated resin did not exceed II 00 cps even after 6 months at 2 parts Celsius and was very good.

Next, this impregnated resin was cured at 110° C. for 6 hours and then further cured at 110° C. for 76 hours to obtain a cured product. The bending strength of this cured product was measured based on JIS K'1203. As a result, a result of 9/- at 2j-°C was obtained, which was very good. In addition, the heating weight decreases with J
Measured based on If3 0.1/θ3.

As a result, the weight loss after heating at tgo℃ for 76 days was 1.0
%, which was a good value. The results of the above initial viscosity, pot life, bending strength, and heating weight loss are summarized in Table 2.

Example 2 0.0 parts of co-allylphenyl glycidyl ether was added to 100 parts of G, Y-J sz (trade name of Ciba Corporation) as an epoxy compound. / part, trihydroxyethyl isocyanurate triacrylate aos, styrene (ll), θ part, methylendomethylenetetrahydrophthalic anhydride, O part, dicumyl peroxide as a catalyst, 0.
/ part, cobalt acetylacetonate 0, J added,
An epoxy-impregnated resin was obtained. The initial viscosity of this impregnated resin was A OcpB at Kota°C.

Next, an insulated coil was manufactured under the same conditions as in Example 1, and the Δ and δ and breakdown voltage were measured and found to be very good as in Example 1. These results are shown in Table 1.

Furthermore, the pot life of the impregnated resin was such that the viscosity did not exceed 4100 cpB even after 6 months at Cos°C.

It was very good. Furthermore, 1 bending strength and 13
The weight loss after heating at 0°C for 16 days was also 1/- and 1. A good value of % was obtained. The results are shown in Table 2.

Example 3 GY-:zss (Ciba brand name) as an epoxy compound
1 molecular weight about 30 (000 phenoxy resin θ, / part, goomethyl--allylphenyl glycidyl ether 'y part-1' lyhydroxye (l co), tylisocyanurate trimethacrylate 70 parts, triallyl trimellitate The same procedure as in Example 1 was carried out except that 70 parts of vinyltoluef!, parts of methyl hexahydrophthalic acid m-hydrate gtr, 06.2 parts of dicumyl peroxide as a catalyst, and BF3-monoethylamine complex o, it were added. The initial viscosity of the epoxy impregnated resin was 2 parts °C and tcps.

Furthermore, an insulated coil was manufactured in the same manner as in Example 1.

When Δ-δ and initial breakdown voltage were measured, Example 1
It was also very good. These results are shown in Table 7.

Further, the pot life of the above-mentioned impregnated resin was very good and did not exceed ao cps even after 6 months at 0°C. These results are shown in Table 1.

Example DF as an epoxy compound! Molecular weight is approximately 30. 5 parts of phenoxy resin of θθ0, co-allylphenyl glycidyl ether lo
1 part, 30 parts of trihuman μxyethyl isocyanurate triacrylate, 3 parts of triallylisocyanurate, 90 parts of methyltetrahydrophthalic anhydride, and 0.1 part of benzoyl peroxide and 063 parts of zinc octylate as catalysts were added. An epoxy-impregnated resin was produced in the same manner as in Example. The initial viscosity of this impregnated resin was kcps at kj°C.

Further, an insulated coil was manufactured in the same manner as in Example 1, and the ΔV and initial breakdown voltage were measured, and as in Example 1, the results were very good. These results are shown in the vX1 table.

Further, the pot life of the above-mentioned impregnated resin was very good and did not exceed θθcps even after 6 months at 2 parts °C.

These results are shown in Table 1.

Comparative example l GY-xrs (trade name of Chipa Co., Ltd.) 7 as an epoxy compound
1 molecular weight per 00 parts is about 30. Phenoxy tree J at θ00
IWtz part 1. Added 2-allylphenyl glycidyl ether/20 parts, trimethylolpropane triacrylate 0 part, styrene-θ part, methyltetrahydrophthalic anhydride "0 part, dicumyl peroxide O as a catalyst, An epoxy-impregnated resin was produced in the same manner as in Example 1, except that 0.2 parts of zinc octylate and 0.2 parts of zinc octylate were added.

When we measured the characteristics of the impregnated resin and the characteristics of the insulated coil, we found that the initial viscosity of the impregnated resin was E j cps, which was reasonable, but the pot life was beyond the range of use according to the present invention for the phenwood resin used for the impregnated resin. The characteristics were very poor (Glo o cp after 3 days)
(exceeded s).

Further, regarding the curing properties and the properties of the insulated coil, the allyl epoxy compound exceeded the range of use according to the present invention, and therefore the bending strength, heating time reduction, and electrical properties of the insulated coil were very poor.

These results are also shown in Tables 1 and 2.

Comparative example As a coepoxy compound ()Y-2 part g (Ciba company product name)
Methyltetrahydrophthalic anhydride g per 700 parts
Replace the s part with 11 ethyl as a catalyst.

An epoxy-impregnated resin was produced in the same manner as in Example except that 0.3 parts of dermethylimidazole (Shikoku Kasei Intermediate product name) was added.

When the properties of this impregnated resin and the properties of the insulated coil were measured, the initial viscosity was 6 at A and t°C! i 0 Cps
Therefore, it was unsuitable as a room temperature epoxy impregnated resin. Also, during the manufacturing stage of the insulated coil, poor impregnation occurred due to the high initial viscosity, resulting in very poor electrical properties. These results are shown in Table 1 and @-Table.

Table 7 Characteristics of insulated coils, measured in oil with 3)/kV/sho dual valve ratio Table Characteristics of epoxy-impregnated resin/) Measured with a BL type viscometer at 21°C [Invention [Effects] As described above, the insulated coil according to the present invention uses a new epoxy-impregnated resin, so that it has improved electrical properties, especially both dielectric loss tangent-voltage characteristics (Δ-δ) and thermal characteristics after thermal deterioration. It is also extremely suitable for use in high-voltage rotating machines, and has extremely great industrial value.

Claims (3)

[Claims] (1) In a method for manufacturing an insulated coil having an insulating layer formed by winding an insulating sheet with a porous insulating material as a backing material on a coil conductor, impregnating this wound layer with an epoxy-impregnated resin, and forming the insulating layer under heat and pressure. As the epoxy-impregnated resin, an allyl epoxy compound having both an allyl group and an epoxy group in one molecule represented by the general formula (I) for 100 parts by weight of an epoxy compound having at least two epoxy groups in one molecule. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) (R is hydrogen, halogen, or monovalent organic group) 0.1 to 100 parts by weight, liquid cyclic acid anhydride 50 to 15
0 parts by weight, and compounds 5 to 3 having a polymerizable double bond
1. A method for manufacturing an insulated coil, characterized by using an epoxy-impregnated resin composition containing 0.00 parts by weight. (2) The epoxy impregnated resin composition contains epoxy compound 10
The method for producing an insulated coil according to claim 1, wherein a phenoxy resin having a molecular weight of 10,000 to 50,000 is blended in an amount of 10 parts by weight or less per 0 parts by weight. (3) Heating pressure molding conditions are heating temperature 100℃~250℃
°C, pressure 5~100kg/cm^2, heating time 4~
The method for manufacturing an insulated coil according to claim 1 or 2, wherein the heating time is 24 hours.