JP2000294061A - Insulating material and winding of electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric insulating material and windings of electric machine capable of forming the windings and insulating covering equipped with a high thermal conductivity and an enhanced current carrying lifetime characteristic. SOLUTION: A high-thermal conductivity insulating tape 1 is composed of a mica layer 3, reinforcing material layer 5 and high-thermal conductivity filler material layer 7, and in these layers, a resin 8 is contained, wherein spherical alumina 6b is included in the filler material layer 7 in such a composition as 1-80 parts by vol. spherical alumina 6b relative to 100 parts by vol. filler material layer. Using this tape 1, a high-thermal conductivity insulation covering 11 is formed on the periphery of a conductor 10 for winding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric machine winding used for a rotating electric machine. In addition, the present invention relates to an insulating material used for forming an insulating coating of an electric winding.

[0002]

2. Description of the Related Art Conventionally, an insulation coating of an electric winding used in a rotating electric machine has a mica layer, a reinforcing material layer, and a filler having a high thermal conductivity, as described in, for example, Japanese Patent Application Laid-Open No. 63-110929. It is formed using an insulating material having a filler layer and a resin contained in each of the layers.

[0003]

However, the conventional electric motor winding in which the insulating coating is formed using the above-mentioned insulating material does not cause any problem when used in a rotating electric machine operated at a low voltage. However, when used in a rotating electric machine that operates at a high voltage, such as a commercial generator or a high-voltage motor, electric defects are likely to occur, and electric characteristics, particularly, the charging life characteristics are degraded. was there.

[0004] A representative object of the present invention is to provide an electric winding having high thermal conductivity and capable of improving the electrical life characteristics, and an insulating material forming an insulating coating therefor. Another object of the present invention is to provide a rotating electric machine having the electric machine winding.

[0005]

Means for Solving the Problems The inventors of the present invention have investigated the causes of the occurrence of electrical defects. As a result, it was found that the problem was caused by minute aggregates of the filler present in the resin of the filler layer constituting the insulating coating. The reason for the presence of such agglomerates is that when the insulating material is manufactured, the resin and the filler are not sufficiently mixed in the process of mixing the resin and the filler, and the dispersibility of the filler becomes insufficient. It turned out to be. Therefore, the inventor of the present invention has repeatedly studied to solve the above fact. As a result, they have found that a filler containing a spherical filler may be used, and the amount of the spherical filler may be 1 to 80 parts by volume per 100 parts by volume.

Here, the insulating material according to the present invention has a mica layer, a reinforcing material layer, a filler layer, and a resin contained in each of these layers. The amount of the spherical filler contained in 100 parts by volume of the layer is 1 to
80 parts by volume. Another insulating material according to the present invention is a laminate in which a mica layer, a reinforcing material layer, and a filler layer are laminated in this order, or a laminate in which a filler layer, a mica layer, and a reinforcing material layer are laminated in this order. And a filler layer containing a spherical filler in the filler layer,
The amount of the spherical filler contained in 0 volume parts was 1 to 80 volume parts.

Another insulating material according to the present invention is such that mica foil and a reinforcing material are impregnated with a resin and adhered.
It is formed by applying a resin impregnated with a filler containing 1 to 80 parts by volume of a spherical filler per 100 parts by volume. The filler contained in the filler layer in the insulating material,
It has a thermal conductivity of at least 5 W / m · K.

Here, the reason why the amount of the spherical filler is 1 to 80 parts by volume per 100 parts by volume is to suppress a decrease in thermal conductivity and to prevent the generation of agglomerates of the filler.
That is, when the amount of the spherical filler is less than 1 part by volume, the dispersibility of the filler is reduced in the process of mixing the resin and the filler when manufacturing the insulating material, and the filler is aggregated in the resin containing the filler. This is because lumps are generated. Also, if the amount of the spherical filler is 80,
If the volume exceeds the volume, the thermal conductivity of the insulating coating decreases when the insulating coating is formed.

An electric winding according to the present invention has a winding conductor and an insulating coating formed outside the winding conductor. The insulating coating is formed by using any of the above insulating materials. is there. Specifically, a winding conductor is formed by winding an insulated conductor a plurality of times, and any of the above-described insulating materials is wound around the outside of the winding conductor, a release material is wound around the outside of the insulating material, and a molding jig is attached. Then, heating is performed at a predetermined temperature while applying an external force from the outer surface of the molding jig, and the resin in the insulating material is cured to form an insulating coating.

A rotating electric machine according to the present invention comprises a stator, a rotor provided inside the stator, a housing containing the stator and the rotor, and a rotating shaft fixed to the housing and rotating the rotor. And a bearing device that freely supports the motor, wherein at least the electric winding is mounted on an iron core constituting a stator.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of the high heat conductive insulating tape of the present embodiment. In the drawings, reference numeral 1 denotes a high thermal conductive insulating tape (or a high thermal conductive prepreg tape),
(Or a withstand voltage layer), a reinforcing material layer 5, and a high thermal conductive filler layer 7 in that order, and a resin 8 contained in each layer. In this embodiment, the mica layer 3, the reinforcing material layer 5,
Although the example of the laminated body laminated | stacked in order of the high thermal conductive filler layer 7 was shown, the laminated body laminated | stacked in order of the high thermal conductive filler layer 7, the mica layer 3, and the reinforcing material layer 5 may be sufficient.

The mica layer 3 is a layer composed of the mica foil 2 and the resin 8. The reinforcing material layer 5 is a layer composed of a glass cloth 4 and a resin 8 formed by weaving glass fibers like a grid. The high thermal conductive filler layer 7 is composed of the alumina particles 6 and the resin 8.
It is a layer consisting of The alumina particle body 6 is a mixture of a random-shaped alumina 6a and a spherical-shaped alumina 6b.
99 to 20 parts by volume is contained per 0 parts by volume, and 1 to 80 parts by volume of the spherical alumina 6b is contained. Alumina particles 6
Has a thermal conductivity of 5 W / m · K or more.

Here, the amount of the spherical alumina 6b is set to 1 to 80 parts by volume per 100 parts by volume of the high thermal conductive filler layer in order to prevent the generation of agglomerates of the filler and to suppress the decrease in thermal conductivity. It is. That is, when the amount of the spherical alumina 6b is less than 1 part by volume, the dispersibility of the filler is reduced in the process of mixing the resin and the filler when producing the insulating material, and the filler is aggregated in the resin containing the filler. This is because lumps are generated. Also, if the amount of the spherical alumina 6b exceeds 80 parts by volume, the thermal conductivity of the insulating coating decreases when the insulating coating is formed. The above is confirmed by an experiment described later.

The high thermal conductive insulating tape 1 is obtained as follows.
A laminated mica foil 2 and a glass cloth 4 were prepared by forming mica particles dispersed in water by a paper machine, and a resin 8 obtained by adding 3 parts by weight of BF ₃ monoethylamine to 100 parts by weight of a novolak type epoxy resin was prepared. It is impregnated and adhered to obtain a laminated mica sheet (a laminate of the mica layer 3 and the reinforcing material layer 5).

Next, random alumina 6a (for example, 95 parts by volume per 100 parts by volume) and spherical alumina 6b
(For example, 5 parts by volume per 100 parts by volume) of an alumina particle body 6 and a resin 8 obtained by adding 3 parts by weight of BF ₃ monoethylamine to 100 parts by weight of a novolak type epoxy resin
Is mixed so that the weight ratio of the alumina particles 6 to the resin 8 is 2: 1 and 10% by weight of methyl ethyl ketone is added thereto, and the side of the reinforcing material layer 5 (or the side of the mica layer 3) of the laminated mica sheet is added. Is applied by a roll coater, and methyl ethyl ketone is volatilized and removed in a drying furnace to obtain a high heat conductive insulating sheet. When the alumina particles 6 and the resin 8 are mixed, the spherical alumina 6b and the resin 8 may be mixed, and then the random-shaped alumina 6a may be added and mixed.
The reverse is also acceptable.

Next, the high heat conductive insulating tape 1 is obtained by slitting the high heat conductive insulating sheet to a width of 30 mm with a slitter.

FIG. 2 shows the configuration of the electric winding of the present embodiment. In the drawing, reference numeral 9 denotes an electric winding, and an insulated conductor 10a
Winding conductor 10 formed by winding a plurality of windings, and winding conductor 10
Is formed of a high heat conductive insulating coating 11 formed using the high heat conductive insulating tape 1 of FIG.

The electric winding 9 is obtained as follows. As shown in FIG. 2, a plurality of insulated conductors 10a are wound a plurality of times to form a winding conductor 1a.
No. 0 is formed, and the high heat conductive insulating tape 1 of FIG. In the present embodiment, the mica layer 3 side of the high thermal conductive insulating tape 1
However, the high heat conductive filler layer 7 side may be used as the winding conductor 10 side. Next, the release tape 12 is wrapped around the high heat conductive insulating tape 1. The reason why the release tape 12 is wound around the outside of the high heat conductive insulating tape 1 in order to prevent adhesion between a molding jig described later and the high heat conductive insulating tape 1. Next, as shown in FIG. 3, the molding jig 13 is attached, and heated at a predetermined temperature while applying an external force from the outer surface of the molding jig 13 to cure the resin 8 contained in the high heat conductive insulating tape 1. Thus, the high heat conductive insulating coating 11 is formed to obtain the electric winding 9.

FIGS. 4 and 5 show the configuration of the rotating electric machine according to the present embodiment. In the drawings, reference numeral 15 denotes a stator frame (or a housing or a casing), on which a stator core 16 is provided. A plurality of axially continuous slots 22 are provided on the inner peripheral surface side of the stator core 16, and the stator windings 18 are accommodated therein. A rotor core 17 is provided inside the stator core 16 via a gap. A plurality of slots continuous in the axial direction are provided on the outer peripheral surface side of the rotor core 17, and a rotor winding 19 is accommodated therein. The rotating shaft 20 of the rotor core 17 is rotatably supported by a bearing device 21 fixed to the stator frame 15.

The stator winding 18 housed in the slot 22
Is obtained by laminating the electric windings 9 shown in FIG. A glass fiber reinforced plastic spring 25 is provided between the electric winding 9 and the slot 22.
A glass fiber reinforced plastic sheet 23, a glass fiber reinforced plastic spring 24, and a wedge 26 are provided between the electric winding 9 located on the inner peripheral side of the stator core 16 and the opening of the slot 22.

FIG. 6 shows the results of the life test of the electric windings performed by the inventor of the present invention, FIG. 8 shows the results of the thermal conductivity test of the electric windings, and FIG. The configuration is shown in FIG.

First, in the voltage application life test, aluminum foil was wound around the outside of the electric winding formed as in the present embodiment and the electric winding formed as in the following comparative example to form electrodes. An AC voltage is applied between the aluminum electrode and the winding conductor of each electric winding, and the time until dielectric breakdown is measured. The result is plotted with the applied voltage (kV / mm) on the vertical axis and the insulation The time (h) until destruction is represented on the horizontal axis.

The electric winding of the comparative example is obtained by applying a high heat conductive insulating tape manufactured as described below to the outside of the winding conductor to form an insulating coating. First, a laminated mica foil and a glass cloth prepared by forming mica particles dispersed in water by a paper machine are prepared, and a novolak epoxy resin 10
A resin obtained by adding 3 parts by weight of BF ₃ monoethylamine to 0 parts by weight is impregnated and bonded to obtain a laminated mica sheet (a laminate of a mica layer and a reinforcing material layer).

Next, a resin obtained by adding 3 parts by weight of BF ₃ monoethylamine to 100 parts by weight of the random-shaped alumina particles and the novolak-type epoxy resin was used. The weight ratio of the random-shaped alumina particles to the resin was 2: 1. And 10% by weight of methyl ethyl ketone is added thereto.
A roll coater is applied to the side of the reinforcing material layer of the laminated mica sheet, and methyl ethyl ketone is volatilized and removed in a drying furnace to obtain a high heat conductive insulating sheet.

Next, the high thermal conductive insulating sheet is slit to a width of 30 mm with a slitter to obtain a high thermal conductive insulating tape.

As is apparent from FIG. 6, the electric winding of the present embodiment was superior to the electric winding of the comparative example in the charging life characteristic. This uses an alumina filler composed of random-shaped alumina and spherical alumina as the filler contained in the high thermal conductive filler layer, and the amount of spherical alumina per 100 parts by volume of the high thermal conductive filler layer is 1 volume part or more. So
This is because the dispersibility of the filler is improved in the process of mixing the resin and the filler when the high thermal conductive insulating tape is manufactured, thereby preventing the generation of fine aggregates of the filler in the resin containing the filler. Therefore, the amount of spherical alumina per 100 parts by volume of the high thermal conductive filler layer may be set to 1 part by volume or more in order to improve the charging life property.

On the other hand, in the thermal conductivity test, a plurality of thermal conductivity measurement samples having different amounts of spherical alumina contained in the high thermal conductivity filler layer were prepared, and the thermal conductivity in the thickness direction of the thermal conductivity measurement sample was measured. Is calculated from the temperature difference between the front and back of the sample for thermal conductivity measurement and the amount of heat penetrating in a steady state. The results are shown by taking the thermal conductivity (%) on the vertical axis and calculating the spherical alumina in the alumina particle body. The amount (volume part) is represented on the horizontal axis.

A plurality of thermal conductivity measuring samples were prepared as shown in FIG. 7 by preparing a plurality of high thermal conductive insulating tapes manufactured as in the present embodiment by changing the amount of spherical alumina contained in the alumina filler. Things. First, the release tape 12a is wrapped around the outside of the copper plate 14, the high thermal conductive insulating tape is partially wrapped around the outside, and the release tape 1a is further wrapped around the outside.
Wind 2 The reason why the release tape 12a is wound around the outside of the copper plate 14 is to prevent the adhesion between the copper plate 14 and the high thermal conductive insulating coating 11.

Next, a molding jig is attached to the outside of the release tape 12 and heated at a predetermined temperature while applying an external force from the outer surface of the molding jig to cure the resin of the high heat conductive insulating tape. Then, a part of the high thermal conductive insulating coating 11 is cut to form a copper plate 14.
, And the removed high thermal conductive insulating coating 11 is processed to a size of 50 mm in diameter. This operation is repeated for each of the plurality of high heat conductive insulating tapes to obtain a plurality of samples for measuring thermal conductivity.

As is apparent from FIG. 8, when the amount of spherical alumina per 100 parts by volume of the high thermal conductive filler layer exceeds 80 parts by volume, the thermal conductivity was reduced. Therefore, in order to suppress a decrease in thermal conductivity, the amount of spherical alumina per 100 parts by volume of the high thermal conductive filler layer may be set to 80 parts by volume or less.

According to the above-described embodiment, as the filler contained in the high thermal conductive filler layer 7, the alumina filler 6 composed of the random alumina 6a and the spherical alumina 6b is used. Since the amount of spherical alumina 6b per volume part is 1 to 80 volume parts, it is possible to prevent the generation of agglomerates of the filler in the filler layer in the process of mixing the filler and the resin during the production of the insulating material. And does not lower the thermal conductivity.

When the electric winding manufactured according to the present embodiment is used as a stator winding of a rotating electric machine, for example, a generator, the heat conductivity can be improved without deteriorating the electrical characteristics of the stator winding. The cooling efficiency can be improved. Therefore, a small-sized and large-capacity rotating electric machine can be realized.

[0034]

According to the insulating material and the electric motor winding of the present invention, the filler layer contains a spherical filler, and the amount of the spherical filler contained in 100 parts by volume of the filler layer is 1 to 80 parts by volume. Therefore, when manufacturing the insulating material, it is possible to prevent the generation of agglomerates of the filler in the filler layer in the process of mixing the filler and the resin, and to reduce the thermal conductivity. Therefore, it is possible to provide an insulating material having a high thermal conductivity and capable of producing an insulating coating for an electric winding, which can improve the charging life characteristic.

According to the electric winding of the present invention, the filler material contains a spherical filler, and the insulating material in which the amount of the spherical filler contained in 100 parts by volume of the filler layer is 1 to 80 parts by volume is used. Since the insulating coating is formed by using the same, it is possible to provide an electric winding having an insulating coating having high thermal conductivity and capable of improving the service life characteristics.

According to the rotating electric machine of the present invention, an insulating material is used in which the filler layer contains a spherical filler and the amount of the spherical filler contained in 100 parts by volume of the filler layer is 1 to 80 parts by volume. Since the electric winding having the insulating coating formed thereon is used for at least the stator winding, the heat conductivity can be improved without deteriorating the electrical characteristics of the stator winding, and the cooling efficiency can be improved. Therefore, a small-sized and large-capacity rotating electric machine can be realized.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a material configuration of a high heat conductive insulating tape according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a configuration of an electric winding according to the embodiment of the present invention.

FIG. 3 is a perspective view for explaining a method of manufacturing the electric winding according to the embodiment of the present invention.

FIG. 4 is a sectional view showing a configuration of a rotating electric machine according to an embodiment of the present invention.

5 is an enlarged perspective view showing a part of the configuration of the stator shown in FIG. 4;

FIG. 6 is a characteristic diagram showing the application life characteristics of the electric winding of the embodiment and the electric winding of the comparative example.

FIG. 7 is a perspective view for explaining a manufacturing process of a sample for measuring thermal conductivity.

FIG. 8 is a characteristic diagram showing thermal conductivity characteristics measured from a plurality of thermal conductivity measurement samples manufactured as in the present embodiment by changing the amount of spherical alumina.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... High thermal conductive insulating tape, 2 ... Mica foil, 3 ... Mica layer, 4 ... Glass cloth, 5 ... Reinforcement layer, 6 ... Alumina particles, 7 ... High thermal conductive filler layer, 8 ... Resin, 9 ... Electric machine Winding, 10 ... winding conductor, 11 ... high thermal conductive insulating coating, 12 ...
Release tape, 13: molding jig, 14: copper plate.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H02K 3/30 H02K 3/30 15/12 15/12 F (72) Inventor Shigeo Amagi Sachiyuki Hitachi, Ibaraki 3-1-1, Machi, Hitachi, Ltd.Hitachi Plant (72) Inventor Masaki Akatsuka 7-1-1, Omika-cho, Hitachi, Ibaraki Pref. 7-1-1, Omika-cho, Hitachi, Japan F-term in Hitachi Research Laboratory, Hitachi Ltd. (Reference) 5G309 CA07 CA11 LA06 PA02 5G333 AA03 AB14 CB11 DA04 DA21 DA22 DA25 FB03 FB08 FB14 5H604 AA03 BB03 BB14 CC01 CC05 CC14 DA03 DA06 DA09 DA15 DB07 DB14 DB20 DB25 PB02 PB03 QC01 QC09 5H615 AA01 BB02 BB14 PP01 PP08 PP13 PP19 PP25 PP28 QQ03 QQ12 QQ19 QQ27 RR02 RR05 RR07 RR09 SS03 SS10 SS32 TT03 TT16 TT2 2 TT23 TT34

Claims (6)

[Claims] 1. A filler having a mica layer, a reinforcing material layer, a filler layer, and a resin contained in each of the layers, wherein the filler layer contains a spherical filler, and 100 parts by volume of the filler layer An insulating material, wherein the amount of the spherical filler contained is 1 to 80 parts by volume. 2. A laminate in which a mica layer, a reinforcing material layer and a filler layer are laminated in this order, or a laminate in which a filler layer, a mica layer and a reinforcing material layer are laminated in this order, and a resin contained in the laminate. Comprising a spherical filler in the filler layer,
An insulating material, wherein the amount of the spherical filler contained in 100 parts by volume of the filler layer is 1 to 80 parts by volume. 3. A mica foil and a reinforcing material are impregnated with a resin and bonded to each other.
An insulating material characterized by being formed by applying a resin impregnated in a filler containing 0 volume parts of a spherical filler. 4. The method according to claim 1, wherein the filler has a thermal conductivity of at least 5 W / m · K.
4. The insulating material according to any one of claims 1 to 3. 5. A winding conductor, and an insulating coating formed outside the winding conductor, wherein the insulating coating is formed by using the insulating material according to any one of claims 1 to 3. An electric winding characterized by the above. 6. A stator, a rotor provided inside the stator, a housing containing the stator and the rotor, and a rotation shaft fixed to the housing and rotatable about the rotor. A rotating electric machine having a bearing device to be supported, wherein the electric machine winding according to claim 5 is mounted on at least an iron core constituting the stator.