JPH11262208A - Stator coil for dynamoelectric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the stator coil of a dynamoelectric machine which enables the improvements of non-destructive electrical characteristics and a voltage application life. SOLUTION: A strand conductor bundle 13 composed of bundled strand conductors 11 to which strand insulations 12 are applied, a composite tape 14 which is composed of a semiconductive tape 15 and a low resistance member 16, which is formed continuously along the surface of the tape 15 in its longitudinal direction, has a lower resistivity than the tape 15 and is wound around the strand conductor bundle 13 to be brought into contact with one of the strand conductors 11 and a ground insulating layer 17 which is formed, so as to envelope the strand conductor bundle 13 with the composite tape 14 therebetween are provided, impregnated with thermosetting resin and cured integrally.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator coil of a high-voltage rotating electric machine in which a coil is accommodated in an iron core slot, and more particularly to a small crack, peeling or void near an interface between a strand conductor bundle and a ground insulating layer. The present invention relates to prevention of a decrease in non-destructive electrical characteristics due to a partial discharge generated due to the partial discharge and a reduction in a service life.

[0002]

2. Description of the Related Art Generally, a stator coil of a high-voltage rotating electric machine is provided with a ground insulating layer around a strand of element wires, impregnated with a thermosetting resin and cured to obtain an insulating layer. However, the vicinity of the strand conductor bundle is uneven when viewed in detail, and a resin is provided between the strand conductor and an insulating tape such as a mica tape or a polyamide tape provided as a ground insulating layer covering the outside of the strand conductor bundle. Defects such as voids that are not clogged or voids due to resin leakage or curing shrinkage during the curing process of the resin even when the resin is clogged. In such a defect, a partial discharge occurs during the operation of the high-voltage rotating electric machine, deteriorating the non-destructive electric characteristics of the stator coil insulation such as the dielectric loss tangent and the maximum discharge charge amount, and shortening the service life. .

In order to prevent the above problems, for example, Japanese Patent Application Laid-Open No. 1-97148 discloses the following. That is, FIG. 7 is a cross-sectional view of a coil end portion of a stator coil of a conventional rotary electric machine of this type, and FIG. 8 is a schematic view illustrating a method of applying the stator coil in FIG.
In the figure, 1 is a strand conductor, 2 is a strand insulation applied to the strand conductor 1, and 3 is a strand conductor bundle formed by bundling the strand conductors 1 having the strand insulation 2 applied thereto. The slot 4 and the coil end 5 are formed in a predetermined shape.

[0006] Reference numeral 6 denotes a removed portion formed by removing the wire insulation 2 at the corner of the wire conductor 1 located at the corner of the wire conductor bundle 3 of the coil end portion 5. Remover 6,
The semi-conductive tape 8 wound continuously between 6 to form a shield layer, and the semi-conductive tape 8 is formed by winding, for example, a mica tape or the like around the outer periphery of the semi-conductive tape 7, and then impregnating and curing a thermosetting resin. This is an insulating layer formed on the ground.

[0005] In the stator coil configured as described above, the semiconductive tape 7 is removed by the removing portion 6.
Is electrically connected to the wire conductor 1 so as to be at the same potential as that of the wire conductor 1 so as to cover the wire conductor bundle 3. Therefore, defects formed at the interface between the wire conductor bundle 3 and the ground insulating layer 8 are caused. It is said that non-destructive electrical characteristics such as dielectric loss tangent and maximum discharge charge amount are prevented from lowering, and that the service life can be expected to be improved.

A stator coil described in Japanese Patent Application Laid-Open No. 1-152939 has a wire conductor bundle 3 formed by bundling wire conductors 1 provided with wire insulation 2 as shown in FIG. The wire insulation 2 of the wire conductor 1a located at the corner of is removed, and the semiconductive tape 7 is wound so that the wire insulation 2 is removed and comes into contact with the wire conductor 1a, thereby fixing the wire conductor 1a. The potential of the semiconductive tape 7 is applied to the strand conductor 1 over the entire length of the core.
Since the potential is set to be the same as the potential of a, the defect caused by the defect formed at the interface between the strand conductor bundle 3 and the ground insulating layer 8 is similar to that disclosed in the above-mentioned JP-A-1-97148. It is said that partial discharge is suppressed, non-destructive electrical characteristics such as dielectric loss tangent and maximum discharge charge amount are prevented from deteriorating, and an improvement in service life can be expected.

[0007]

A conventional stator coil of a rotating electric machine is constructed as described above.
In the method disclosed in Japanese Patent No. 97148, the semiconductive tape 7 connected to both the removing portions 6 formed on the coil end portion is applied to the entire slot portion 4. 10 for the material of the tape 7
^{When the} resistance is lower than ² Ω, the eddy current generated by the field magnetic flux increases, causing a large loss and a cause of local overheating. On the other hand, when the resistance is higher than 10 ⁵ Ω, the dielectric loss tangent which is an index of the insulation characteristic is obtained. since the worsens, since the specific resistivity is used is of the order of 10 ² Ω~10 ⁵ Ω, the resistance of the semi-conductive tape 7 between the two removal portions 6 a long model of the stator core Therefore, the closer to the center of the stator core, the higher the potential of the semiconductive tape 7 is, and the intended purpose of suppressing the partial discharge and improving the non-destructive electrical characteristics and the service life is not sufficiently achieved. There was a problem.

The method of removing the wire insulation 2 at the corners of the wire conductor 1 as described in JP-A-1-152939 corresponds to a stator slot after the formation of the wire conductor bundle 3. In a generator that requires a step of providing a removed portion over the entire length of the portion and performs wire transposition for equalizing the generated voltage, the position of one wire conductor 1 is within the wire conductor bundle 3. Therefore, there is a problem that it is difficult to remove the wire insulation 2 over the entire length.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a stator coil of a rotating electric machine capable of reliably suppressing partial discharge and improving nondestructive electric characteristics and service life. It is intended to do so.

[0010]

According to a first aspect of the present invention, there is provided a stator coil for a rotary electric machine, comprising: a wire conductor bundle formed by bundling wire insulated wires; A tape and a low-resistance member formed continuously with a width smaller than the width of the tape in the longitudinal direction of the surface of the tape and having a lower resistivity than the tape. The composite tape is provided with a composite tape which is wound while being connected to the base material, and a ground insulating layer formed so as to surround the element conductor bundle via the composite tape, and is integrally impregnated and cured with a thermosetting resin.

According to a second aspect of the present invention, there is provided a stator coil for a rotating electric machine, wherein the composite tape according to the first aspect is wound in a spiral shape.

According to a third aspect of the present invention, there is provided a stator coil for a rotating electric machine, wherein the composite tape is wound so that the low-resistance member is on the strand conductor side.

According to a fourth aspect of the present invention, there is provided a stator coil for a rotary electric machine according to any one of the first to third aspects, wherein a metal is used as the low-resistance member.

According to a fifth aspect of the present invention, there is provided a stator coil for a rotating electric machine according to any one of the first to third aspects, wherein the low-resistance member is formed to have a width smaller than the width of the strand conductor. .

According to a sixth aspect of the present invention, there is provided a stator coil for a rotating electric machine according to any one of the first to third aspects.
The low resistivity member has a specific resistivity of 10 ² Ω or less.

According to a seventh aspect of the present invention, there is provided a stator coil for a rotating electric machine, comprising: a wire conductor bundle formed by bundling wire insulated wires; A semiconductive tape that is electrically connected to and wound around a wire conductor at a plurality of locations at an interval of 1000 mm or less, and a ground insulating layer formed so as to surround the wire conductor bundle via the tape. , Which are integrally impregnated and cured with a thermosetting resin.

According to a eighth aspect of the present invention, there is provided a stator coil for a rotary electric machine according to the first or seventh aspect, wherein the stator coil is electrically connected to the strand conductor by welding a semiconductive tape. is there.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a configuration of a stator coil of a rotary electric machine according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view schematically showing a cross section in the slot direction of the stator coil of the rotary electric machine in FIG. 3 is a cross-sectional view showing the configuration of the composite tape in FIG. 1, and FIG. 4 is a cross-sectional view showing a configuration of the composite tape in FIG. 1 different from that in FIG.

In the figure, 11 is a strand conductor, 12 is a strand insulation applied to the strand conductor 11, and 13 is a strand formed by bundling the strand conductors 11 having the strand insulation 12 applied thereto. The conductor bundle 14 has a specific resistivity of 10 ² to 1 as shown in FIG.
On the 0 and ⁵ Omega is semiconductive tape 15 having a low resistivity than the tape 15 of this semi-conductive, such as copper, aluminum, a metal tape such as stainless steel, is adhered through an adhesive layer This is a composite tape having a low resistance member 16 formed thereon.

The composite tape 14 is formed in a stator slot around the wire conductor bundle 13 so that the low-resistance member 16 is on the side of the wire conductor 11 and does not form a portion where the low-resistance members 16 overlap each other. In a portion corresponding to the stator slot, a single wire conductor 11a from which the wire insulation 12 has been partially removed and the low-resistance member 16 are electrically formed in a spiral shape over a range including the entire length of the corresponding portion. And a shield layer is formed. Reference numeral 17 denotes a wound composite tape, that is, a ground insulating layer formed by arranging an insulating material such as a mica laminate or a polyamide nonwoven fabric around the shield layer, and then impregnating and curing a thermosetting impregnating resin by a vacuum impregnation method. It is.

As described above, according to the first embodiment, a semiconductive tape 15 is provided around the wire conductor bundle 13, and an inherent lower than the semiconductive tape 15 is formed on the semiconductive tape 15. The composite tape 14 formed with the low-resistance member 16 having resistivity is wound, and the low-resistance member 16 and the wire insulation 12 are wound.
Since the shield layer is formed by electrically connecting the single wire conductor 11a from which the wire has been removed, defects such as voids existing between the wire conductor bundle 13 and the shield layer are shielded at the same potential. Since the layer is surrounded by the layers, the occurrence of partial discharge is reliably suppressed, and the nondestructive electric characteristics such as the dielectric loss tangent and the maximum discharge charge amount, and the improvement of the service life can be improved.

Further, since the composite tape 14 is spirally wound so as not to form a portion where the low-resistance members 16 overlap each other, a low-resistance portion having a large area is not formed. A shield layer having a constant potential can be formed while suppressing the voltage.

As shown in FIG. 3, the end of the low resistance member 16 and the semiconductive tape 15
Have been described, the low-resistance member 1
The formation position of the low-resistance member 16 is not limited to this.
It is sufficient that the width is smaller than the width of the tape 5. For example, as shown in FIG. Further, in the above configuration, the case where the metal tape is applied as the low resistance member 16 has been described. However, a metal wire or a metal mesh may be stuck on the semiconductive tape 15, Fifteen
A metal film may be formed thereon by plating, vapor deposition, or the like.

If a material other than metal having a specific resistivity of 10 ² Ω or less is used as the low-resistance member 16, uniformity of potential can be more effectively obtained as in the case of metal. Furthermore, in the above configuration, the composite tape 14 is wound so that the low-resistance member 16 is on the strand conductor 11 side, thereby facilitating the electrical connection between the low-resistance member 16 and the strand conductor 11. The low-resistance member 16 is a wire conductor 11
There is no need to be on the side, and since the low-resistance member 16 always exists in a part of the width of the semiconductive tape 15, the semiconductive tape 15 is connected to the strand conductor 11 via the semiconductive tape 15. Although the resistance of the semiconductive tape 15 existing between the low-resistance member 16 and the wire conductor 11 is inserted in series, the resistance is sufficiently small because the thickness is small, so that the low-resistance The member 16 and the wire conductor 11 have substantially the same potential, and can sufficiently serve as a shield layer.

Embodiment 2 FIG. 5 is a schematic diagram showing a configuration of a stator coil of a rotary electric machine according to Embodiment 2 of the present invention. In the figure, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. Reference numeral 18 denotes a semiconductive tape wound around the wire conductor bundle 13 over a range including the entire length corresponding to the stator slot. A position where the wire insulation 12 is removed at a plurality of intervals of 1000 mm or less. Then, a shield layer is formed by being electrically connected to one of the strand conductors 11, and a ground insulating layer 17 is formed around the shield layer.
Are formed.

As described above, according to the second embodiment, the semiconductive tape 18 is wound around the wire conductor bundle 13 over a range including the entire length corresponding to the stator slot. Insulation 2 is 1000 mm or less spacing l
At a position where a plurality of portions are removed, the shield layer is formed by being electrically connected to one of the strand conductors 11. For example, when the connection is made at one location outside the stator slot, the stator slot length is reduced. When it is large, the dielectric loss tangent becomes large due to the resistance. When the stator slot length is 5 m and the specific resistivity of the semiconductive tape is 10 ⁴ Ω, the dielectric loss tangent is about 5%.
High value, which is a very bad value for the non-destructive electric characteristics. On the other hand, the increase can be suppressed to about 0.2%, the non-destructive electric characteristics can be improved, and the potential of the shield layer is kept constant. Thus, the occurrence of partial discharge can be prevented.

Embodiment 3 FIG. 6 is a sectional view schematically showing a configuration of a stator coil of a rotary electric machine according to Embodiment 3 of the present invention. In the figure, the same parts as those in the second embodiment are denoted by the same reference numerals, and the description is omitted.
Numeral 19 denotes welding means such as an ultrasonic welding machine or a local heating device, which melts polyester or polyamide as a base material of the semiconductive tape 18 and removes the wire insulation 12 of the wire conductor 11 from the wire insulation 12. Weld.

As described above, according to the third embodiment, since the base material of the semiconductive tape 18 is melted and welded to the strand conductor 11, the thermosetting resin is semiconductive at the time of impregnation. The gap between the tape 18 and the wire conductor 11 does not intrude between the tape 18 and the wire conductor 11 and the contact between them can be prevented. Although the third embodiment has been described with reference to the case where the present invention is applied to the stator coil according to the second embodiment, it goes without saying that the same effect can be exerted even when the third embodiment is applied to the stator coil according to the first embodiment. No.

[0029]

As described above, according to the first aspect of the present invention, a wire conductor bundle formed by bundling wire insulated wires, a semiconductive tape, and a A low-resistance member formed continuously with a width smaller than the width of the tape in the longitudinal direction of the surface and having a lower resistivity than the tape; Equipped with a composite tape to be turned, and a ground insulating layer formed so as to surround the element conductor bundle through the composite tape, so that it is integrally impregnated and cured with thermosetting resin, so partial discharge is reliably suppressed. In addition, it is possible to provide a stator coil of a rotating electric machine capable of improving non-destructive electric characteristics and service life.

According to a second aspect of the present invention, in the first aspect, the composite tape is wound in a spiral shape, so that the eddy current can be suppressed and a shield layer having a constant potential can be formed. An electric machine stator coil can be provided.

According to a third aspect of the present invention, in the first aspect, the composite tape is wound so that the low-resistance member is on the strand conductor side, so that the electrical connection between the low-resistance member and the strand conductor is made. It is possible to provide a stator coil of a rotating electric machine that can be easily connected.

According to a fourth aspect of the present invention, in any one of the first to third aspects, since a metal is used as the low resistance member, the stator coil of the rotating electric machine in which the low resistance member can be easily formed is provided. Can be provided.

According to a fifth aspect of the present invention, in any one of the first to third aspects, the low-resistance member is formed with a width smaller than the width of the wire conductor, so that the eddy current is suppressed while suppressing the eddy current. It is possible to provide a stator coil of a rotating electric machine capable of forming a potential shield layer.

According to the sixth aspect of the present invention, in any one of the first to third aspects, the specific resistance of the low-resistance member is set to 10 ² Ω or less, so that the uniformity of the potential can be more effectively improved. It is possible to provide a stator coil of a rotating electric machine that can be obtained.

According to the seventh aspect of the present invention, a wire conductor bundle formed by bundling wire conductors subjected to wire insulation is provided.
A semiconductive tape that is electrically connected to and wound around the wire conductor bundle at a plurality of locations at intervals of 1000 mm or less to one wire conductor, and to surround the wire conductor bundle via the tape. A stator coil for a rotating electric machine that has a formed ground insulating layer and is integrally impregnated and cured with a thermosetting resin, so that partial discharge is reliably suppressed and non-destructive electrical characteristics and service life can be improved. Can be provided.

According to the eighth aspect of the present invention, in the first or seventh aspect, the semiconductive tape is welded to electrically connect the wire conductor to the wire conductor, so that more reliable electrical connection is achieved. Can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a stator coil of a rotary electric machine according to Embodiment 1 of the present invention.

FIG. 2 is a cross-sectional view schematically showing a cross section of a stator coil of the rotating electric machine in FIG. 1 in a slot direction.

FIG. 3 is a cross-sectional view showing a configuration of the composite tape in FIG.

FIG. 4 is a cross-sectional view showing a configuration of the composite tape in FIG. 1 different from that in FIG. 3;

FIG. 5 is a schematic diagram showing a configuration of a stator coil of a rotary electric machine according to Embodiment 2 of the present invention.

FIG. 6 is a cross-sectional view schematically illustrating a configuration of a stator coil of a rotary electric machine according to Embodiment 3 of the present invention.

FIG. 7 is a cross-sectional view of a coil end portion of a stator coil of a conventional rotating electric machine.

FIG. 8 is a schematic view showing a method of applying the stator coil in FIG. 7;

FIG. 9 is a cross-sectional view of a coil end portion of a stator coil of a conventional rotating electric machine different from FIG.

[Explanation of symbols]

11 strand conductor, 12 strand insulation, 13 strand conductor bundle,
14 Composite tape, 15, 18 Semiconductive tape, 1
6 Low resistance member, 17 ground insulating layer, 19 welding means.

Claims (8)

[Claims] 1. A wire conductor bundle formed by bundling wire insulated wires, a semiconductive tape and a continuous tape having a width smaller than the width of the tape in the longitudinal direction of the surface of the tape. A composite tape formed of a low-resistance member having a lower resistivity than the tape and electrically wound around one of the element conductors around the element conductor bundle, and the composite tape. A stator coil for a rotating electric machine, comprising: a ground insulating layer formed so as to surround the above-mentioned strand conductor bundle with a thermosetting resin integrally impregnated and cured. 2. The stator coil according to claim 1, wherein the composite tape is spirally wound. 3. The stator coil according to claim 1, wherein the composite tape is wound so that the low-resistance member is on the strand conductor side. 4. The stator coil according to claim 1, wherein the low resistance member is a metal. 5. The stator coil according to claim 1, wherein the low resistance member has a width smaller than a width of the wire conductor. 6. The stator coil according to claim 1, wherein the low-resistance member has a specific resistivity of 10 ² Ω or less. 7. A wire conductor bundle formed by bundling wire conductors subjected to wire insulation, and a plurality of electric wires are provided around the wire conductor bundle at a plurality of locations at a distance of 1000 mm or less per one wire conductor. A semiconductive tape that is electrically connected and wound, and a ground insulating layer that is formed so as to surround the element wire bundle via the tape, and is integrally impregnated and cured with a thermosetting resin. A stator coil for a rotating electric machine, characterized in that: 8. The stator coil according to claim 1, wherein the stator coil is electrically connected to the strand conductor by welding a semiconductive tape.