JPH0638424A - Stator coil of high-tension rotating electric machine - Google Patents

Abstract

PURPOSE:To obtain a stator coil with good cold and heat resistant cycle properties comprising a surface corona preventive layer having a stress relaxation function capable of relaxing a thermal stress without reducing a resin impregnation. CONSTITUTION:A ground main insulating layer 3 with which the surface of an alignment coil is covered and a surface corona preventive layer 14 formed on the outside of the insulating layer 3 are provided. The surface corona preventive layer 14 of a stator coil 11 integrated with a stator core 10 by a full impregnation method comprises a taping layer 12 made of a semi-conductive fiber tape wound on the surface of the main insulating layer 3 in a double layer and a composite semi-conductive sheet 13 interposed in a part opposite to a sidewall of a slot 9 between the layers. The composite semi-conductive sheet 13 is formed on one surface of a semi-conductive fiber substrate with materials having a semi-conductive stress relaxation layer consisting of any one of semi- conductive rubber layer, semi-conductive laminate glass layer and semi- conductive semi-curing resin layer, and further the surface corona preventive layer 14 has a relaxation function of a thermal stress for acting between the core and the coil.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator coil for a high pressure rotating electric machine of a total impregnation type in which a stator coil is housed in a slot and then impregnated with a resin, and more particularly to improvement of the structure of a surface corona preventive layer thereof.

[0002]

2. Description of the Related Art In a stator coil of a high-voltage rotating electric machine such as an induction motor or a generator, the resin impregnation method includes a method of impregnating the stator coil with a resin and an unimpregnated stator coil in a slot. Further, it is roughly classified into a total impregnation method in which the coils are electrically connected to each other and then the resin is impregnated. Especially, in the stator coil of the full impregnation method, the gap between the stator coil and the iron core slot is filled with a cured product of impregnated resin, the iron core and the coil are integrated, and the thermal conductivity between the coil and the iron core is high, It has excellent cooling performance and has the advantage of simplifying the resin impregnation and heat curing processes, and is widely applied as an insulation treatment method for small to large high-voltage rotating electrical machines.

FIG. 6 is a sectional view showing an essential part of a stator coil of a conventional high-voltage rotating electric machine of the full impregnation type. In the figure, a stator coil 1 is provided with a plurality of insulated wire conductors before inserting a rectangular parallelepiped coil side portion (referred to as a slot portion) into a slot 9 radially formed in a stator core 10. -A base of the ground main insulating layer 3 obtained by taping a mica such as a glass-based mica or a film-based mica a predetermined number of times on the surface of the aligned coil conductor 2 which is wound or has a Hebel rearrangement. A material layer is formed, and a semiconductive glass tape, a semiconductive film tape, and
Alternatively, a base layer of the surface corona preventive layer 4 is formed by tapering a semi-conductive tape such as a semi-conductive non-woven tape with a predetermined thickness. The unimpregnated stator coil (also referred to as a white coil) thus formed is housed in the slot 9 with two upper and lower strips with the inter-coil insulating material 5 interposed between the coils.
The opening of the slot is wedged through the insulating material 6 under the wedge.
After that, the white coil is fixed to the stator core, the coils are electrically connected to each other, and then a resin impregnation process is performed by the full impregnation method.

In the resin impregnation process, after the stator core 10 having the stator coil wound thereon is housed in a vacuum impregnated layer and dried in vacuum,
Vacuum impregnation of thermosetting impregnating resin such as epoxy resin at a predetermined temperature, and then pressure impregnation in the impregnation tank,
Then, the impregnation tank is transferred to a curing tank at a predetermined temperature and the impregnated resin is heat-cured to form the stator coil 1 having the groundless main insulating layer 3 impregnated with voidless material, and to prevent the resin-impregnated surface corona. The layer 4 is in conductive contact with the iron core 10 to keep the potential of the surface corona preventive layer at substantially the same potential as the grounded stator iron core, and the hardened material 7 of the impregnated resin impregnated in the gap between the core and A stator winding of a high-voltage rotating electric machine, which is joined to the wall surface and in which the stator core 10 and the stator coil 1 are integrated, is formed.

The thus-obtained stator winding of the full impregnation method has excellent thermal conductivity with the iron core and can increase the current density of the aligned coil conductors 2 to downsize the high voltage rotating electric machine. In a rotating electric machine that has a high operating temperature and frequently starts and stops, thermal stress is generated between the integrated iron core 10 and the stator coil 1 due to the difference in thermal expansion coefficient between them, and Peeling occurs at weak points that cannot withstand stress. If this peeling point is on the interface between the inner wall surface of the slot 9 and the surface corona preventive layer 4, the surface corona preventive layer having semiconductivity keeps conductive contact with the iron core in a portion other than the peeled portion, thereby preventing the surface corona preventive. Since the potential of the layer is maintained near the potential of the grounded iron core, it is possible to avoid damage to the stator coil 1 due to generation of surface corona at the peeled portion. However, if peeling occurs due to thermal stress between the layers of the main ground insulating layer 3 or at the interface between the main ground insulating layer and the surface corona preventive layer, a high voltage due to electrostatic capacitance partial pressure is generated at this peeled portion, which causes There is a problem that discharge deterioration of the constituent materials occurs due to internal partial discharge, which causes deterioration of the insulation performance of the stator coil, and sometimes progresses to a situation where dielectric breakdown of the main insulating layer to ground progresses.

In order to avoid such an unexpected situation,
As a base material layer for the surface corona preventive layer 4, a conductive polytetrafluoroethylene tape is wound on the outside of the ground main insulating layer 3 to form a tape layer, and ethylene tetrafluoride is applied to the cured resin of the impregnated resin. By using the peelability of the surface corona prevention layer 4 and the inner wall surface of the slot 9 to suppress the generation of the surface corona, the heat acting between the stator coil and the iron core is suppressed. There is known one configured to relieve stress (Japanese Patent Laid-Open No. Sho 56-83237).

Further, as the base material layer of the surface corona preventive layer 4, a conductive tetrafluoroethylene tape having a surface on the side facing the main insulating layer against the surface is used, and the main insulating layer 3 against the ground and the surface corona preventive layer are used. It is known that the internal partial discharge deterioration of the constituent materials can be prevented more reliably by making the peeling less likely to occur at the interface with No. 4 (JP-A-58-179143).
Issue).

[0008]

SUMMARY OF THE INVENTION Conductive tetrafluoroethylene tape as a surface corona preventive layer or a conductive tetrafluoride ethylene tape having a surface on the side of the main insulating layer against the surface blocked.
In the conventional technique using a magnetic head, the thermal stress is relieved by causing peeling between the surface corona preventive layer and the inner wall surface of the slot, and the internal partial discharge is generated, and the discharge deterioration of the constituent materials caused by the internal partial discharge is prevented. It becomes possible to suppress. However, since conductive tetrafluoride ethylene tape has no permeability of impregnated resin, it is conventional to use semi-conductive glass tape or semi-conductive non-woven fabric tape for the base layer of the surface corona preventive layer. As in the technology, it becomes difficult to supply the impregnating resin to the base material layer of the ground main insulating layer through this base material layer, and the ground main insulating layer 3 or the ground main insulating layer 3 and the surface corona prevention after the curing treatment are completed. There is a problem that unimpregnated voids remain in the vicinity of the interface with the layer 4, and internal partial discharge and partial discharge deterioration of constituent materials due to the internal discharge occur in this void, and improvement thereof is demanded.

An object of the present invention is to provide a stator coil which is provided with a surface corona preventive layer capable of relaxing thermal stress without impairing resin impregnation property and therefore has excellent cold-heat cycle resistance and does not generate harmful partial discharge. is there.

[0010]

In order to solve the above problems, according to the present invention, a ground main insulating layer covering the surface of an aligned coil conductor and a surface corona preventive layer formed on the outside thereof are provided. After being inserted into the slots of the stator core, a cured product of a thermosetting impregnating resin impregnated with vacuum pressure is applied to the stator coil integrated with the iron core, whereby the ground main insulating layer and the stator core A semi-conductive stress relaxation layer for relaxing the stress acting between them is provided at a major part of the surface corona preventive layer.

Further, the surface corona preventive layer is a portion of the semi-conductive fiber tape which is wound in two layers on the surface of the main insulating layer, and a portion facing the side wall surface of the slot between the layers. And a semiconductive rubber layer on one side of the semiconductive fiber base material, and a semiconductive laminate glass. Layer or a semiconductive stress-relieving layer comprising a semiconductive semi-cured resin layer, wherein the surface corona preventive layer is formed to have semiconductivity in the thickness direction as well. And

Further, the surface corona preventive layer comprises a tape layer of a composite semiconductive tape wound on the surface of the main insulating layer, and the composite semiconductive tape is made of a semiconductive rubber. layer,
A semi-conductive stress relaxation layer consisting of either a semi-conductive laminate glass layer or a semi-conductive semi-cured resin layer, and this semi-conductive stress relaxation layer is adhered to and supported on one side or both sides thereof. The surface corona preventive layer is made of a composite material with a semiconductive fiber base material, and is formed so as to have semiconductivity also in the thickness direction.

Furthermore, the surface corona preventive layer comprises a tape layer of a composite semiconducting tape wound on the surface of the main insulating layer, the composite semiconducting tape having a single-sided semiconducting surface. A base material made of perforated plastic film that has been subjected to property treatment,
A semi-conducting stress relaxation layer consisting of a semi-conducting rubber layer, a semi-conducting laminate glass layer, or a semi-conducting semi-curing resin layer formed by closely adhering to the one-side semi-conducting treated surface. And the surface corona preventive layer is taped on the surface of the main insulating layer with the semiconductive stress relaxation layer on the outside.

[0014]

In the structure of the present invention, the semi-conductive stress relaxation layer for relaxing the stress acting between the ground main insulating layer and the stator core is provided to prevent the surface corona of the stator coil of the high-voltage rotating electric machine by the full impregnation method. By providing for the key points of the layer, the semi-conductive surface corona prevention layer prevents the surface corona from coming into contact with the iron core and prevents the generation of surface corona. The semiconductive stress relaxation layer provided in the surface corona preventive layer absorbs and relaxes the stress, and peeling is caused by thermal stress between the layers of the main ground insulating layer or near the interface between the main ground insulating layer and the surface corona preventive layer. Since it also has a function of avoiding the occurrence of the occurrence, it is possible to prevent the discharge deterioration of the constituent materials due to the occurrence of partial discharge in the peeling portion, and improve the resistance to cold and heat cycles of the stator coil. Kill.

As a specific example, the surface corona preventive layer is
Semi-conductive fiber tape wound in two layers on the surface of the main insulating layer
And a composite semiconductive sheet interposed in a portion of the layer facing the side wall surface of the slot, and the composite semiconductive sheet is a semiconductive fiber base material. Semi-conductive rubber layer, semi-conductive laminate glass layer, on one surface,
Alternatively, the surface corona-preventing layer can be formed by including a semi-conductive stress relaxation layer made of any one of the semi-conductive and semi-cured resin layers, and the surface corona-preventing layer having semi-conductivity in its thickness direction. When the two semi-conductive fiber tape layers of No. 2 function as a resin impregnated passage to the ground main insulating layer, contribute to the formation of the voidless impregnated ground main insulating layer with few defects, and when the curing treatment is completed. Then, the two layers of semi-conductive fiber tape exert a binding force to prevent the occurrence of peeling at the interface between the main ground insulating layer and the surface corona preventive layer. Further, in the portion facing the side wall surface of the slot where the binding force is difficult to apply, the semiconductive stress relaxation layer interposed between the layers of the semiconductive fiber tape layer of this portion causes thermal expansion of the coil and the iron core. It absorbs and relaxes the thermal stress caused by the difference and prevents the separation of the main insulating layer from the ground, thus improving the resistance to cold and heat cycles of the stator coil and preventing deterioration of the main insulating layer to ground due to internal partial discharge. Is obtained.

If the semi-conductive stress relaxation layer is made of a semi-conductive rubber material or a semi-conductive laminate glass material in which shrunk glass fibers are bonded with a conductive binder, the coefficient of thermal expansion is large. The function of absorbing thermal stress is obtained by utilizing the property of the semi-conductive stress relaxation layer that is rich in rubber elasticity or elasticity, and if a semi-conductive semi-cured resin layer is used, it becomes brittle when heat-cured. Utilizing the properties of semi-cured resin
Thermal stress relieves stress by causing cracks in the semi-conductive stress relaxation layer inside the layer, preventing the occurrence of delamination within the main ground insulation layer, and these cracks around the layer in the thickness direction. Also, it is short-circuited by the surface corona preventive layer having conductivity, and acts to prevent discharge from occurring in the crack.

Further, the surface corona preventive layer comprises a tape layer of a composite semiconductive tape wound on the surface of the main insulating layer, and the composite semiconductive tape is made of a semiconductive rubber. layer,
A semi-conductive stress relaxation layer consisting of either a semi-conductive laminate glass layer or a semi-conductive semi-cured resin layer, and this semi-conductive stress relaxation layer is adhered to and supported on one side or both sides thereof. If the surface corona preventive layer is made of a composite material with a semi-conductive fiber base material and is formed so as to have semi-conductivity in the thickness direction as well, a simplified taping process is performed over the entire surface of the coil. A stress relaxation function similar to that of the above-mentioned embodiment can be obtained, and by using the composite semiconductive tape having a two-layer structure, a function of relaxing thermal stress near the interface with the slot can be obtained.

Furthermore, the surface corona preventive layer comprises a tape layer of a composite semiconducting tape wound on the surface of the main insulating layer. If the perforated plastic film treated on one side with semi-conductivity is used, the holes formed by being dispersed in the plastic film serve as impregnation passages, and the function of maintaining the voidless impregnation property of the ground main insulating layer can be obtained.

[0019]

EXAMPLES The present invention will be described below based on examples. FIG. 1 is a sectional view showing a stator coil of a high-voltage rotating electric machine according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view showing a surface corona preventing layer portion in the embodiment. Duplicated description will be omitted by giving reference numerals. In the figure, a stator coil 11 is a semi-conductive polyester non-woven fabric wound in two layers on the surface of the main insulating layer 3 as a surface corona prevention layer 12 covering the outside of the main insulating layer 3 with ground, and a semi-conductive layer. 12 of glass fiber tape or semi-conductive fiber tape such as polyamide paper mixed with conductive fibers, and the like 12, and 12;
A composite semiconductive sheet 13 interposed between portions of the interlayer 9 facing the side wall surface of the slot 9 is formed by a thermosetting impregnating resin impregnated by a total impregnation method. The preventive layer 14 is impregnated with voidless material and is given a withstand voltage performance by thermosetting treatment, and the stator coil 11 and the stator core 10 are bonded and integrated by the cured product 7 of the impregnated resin, and have excellent thermal conductivity. A stator of a high-voltage rotating electric machine having a stator winding is formed.

The composite semiconductive sheet 13 comprises the above-mentioned semiconductive fiber tape as a base material 13A and a semiconductive stress relaxation layer 13B formed on one surface thereof.
As the semi-conductive stress relaxation layer 13B, a silicone rubber-based semi-conductive rubber material, a semi-conductive laminate glass material in which shrink-processed glass fibers are formed into a sheet with a semi-conductive binder,
Alternatively, any one of the semi-conductive semi-cured resin layers in which graphite powder is mixed with epoxy resin containing a small amount of a curing accelerator is used, and the surface corona prevention layer 14 is configured to have semi-conductivity also in the thickness direction. It

In the stator coil 11 thus constructed, the two semi-conductive fiber tape layers 12 of the surface corona preventive layer 14 function as resin impregnating passages to the ground main insulating layer 3 and are voidless impregnated. The main layer of the ground insulating layer and its surface corona preventive layer contribute to the formation of the main insulating layer with less defects and at the end of the curing treatment, the two semiconductive fiber tapes exert a binding force. The function of preventing the occurrence of peeling at the interface with is obtained. Further, in the portion facing the side wall surface of the slot where the binding force is difficult to apply, the semiconductive stress relaxation layer 13B interposed between the layers of the semiconductive fiber tape layer 12 at this portion is formed between the coil and the iron core. It absorbs and relaxes the thermal stress caused by the difference in thermal expansion, and prevents the main insulating layer from separating from peeling, preventing the main insulating layer from deteriorating due to internal partial discharge and improving the resistance to cold and heat cycling of the stator coil. The function to do is obtained.

If the semiconductive stress relaxation layer is composed of a semiconductive rubber material or a semiconductive laminar glass material, the semiconductive stress having a large coefficient of thermal expansion and rich rubber elasticity or elasticity is obtained. The function of absorbing the thermal stress is obtained by utilizing the property of the relaxation layer, and if the semi-conductive semi-cured resin layer is used, the property of the semi-conductive semi-cured resin, which becomes brittle by heat curing, is used. The stress relieves stress in the semiconductive stress relaxation layer by causing cracks in the layer-wise direction inside the layer, preventing the occurrence of delamination in the main ground insulating layer, and the cracks in the thickness direction around it. Is also short-circuited by the electrically conductive surface corona-preventing layer and prevents discharge from occurring in the crack. Therefore, the obtained stator coil 11 is excellent in insulation performance and resistance to cold and heat cycles, has a high operating temperature, and does not generate surface corona and internal partial discharge even when applied to a rotating electric machine that frequently repeats start and stop, The stator coil of the high-voltage rotating electric machine having excellent insulation reliability can be obtained.

FIG. 3 is a sectional view showing a stator coil of a high-voltage rotating electric machine according to another embodiment of the present invention, and FIG. 4 is an enlarged sectional view showing a surface corona preventive layer in another embodiment. In the figure, the surface corona prevention layer 24 is the main insulating layer 3
The present embodiment is different from the above-mentioned embodiment in that it is formed as a tape layer of the composite semiconductive tape 13 wound on the surface of the composite semiconductive tape 13. Similarly to the above, the semi-conductive stress relaxation layer 13B made of any one of the semi-conductive rubber layer, the semi-conductive laminate glass layer, and the semi-conductive semi-cured resin layer, and the semi-conductive stress relaxation layer 13B. And a semi-conductive fiber base material (tape) 13A that closely adheres to and supports one surface or both surfaces of the surface, and the surface corona preventive layer is formed to have semi-conductivity in the thickness direction as well. It Therefore, if the composite semi-conductive tape 13 is taped by the mechanized taping process to form the surface corona preventive layer 14, the same stress relaxation function as that of the above-described embodiment is provided over the entire surface of the coil. Is obtained.
Further, by using the composite semiconductive tape having a two-layer structure, a function of relaxing thermal stress near the interface with the slot can be obtained.

Further, as another embodiment of the present invention, a perforated plastic film such as a polyester film or a polyimide film which is semi-conductive on one side is used as a base material layer of the composite semi-conductive tape 13 and the semi-conductive property thereof is used. A composite semiconductive tape supporting the semiconductive stress relaxation layer 13B on the treated surface side was wound with the base material facing the main insulating layer side to form a surface corona preventive layer. As a result, the holes formed by being dispersed in the plastic film serve as impregnation passages, and the function of maintaining the voidless impregnation of the main ground insulating layer is obtained, and at the same time, the semiconductive stress relaxation layer is formed on the surface of the stator coil. Since the thermal stress is relieved, the deterioration of the resin impregnating property, which was a problem in the conventional technology using conductive tetrafluoroethylene tape, is avoided, the operating temperature is high, and the rotating electrical machine that repeats start-stop frequently. Even if it is applied to, the stator coil of the high-voltage rotating electric machine, which does not generate surface corona and internal partial discharge and has excellent insulation reliability, can be obtained. Also,
This composite semiconductive tape is suitable for high-speed mechanical winding, and has the advantage that the step of taping the surface corona preventive layer can be saved and the thickness of the surface corona preventive layer can be reduced.

FIG. 5 is a characteristic diagram showing changes in the dielectric loss angle due to the cooling / heating cycle of the stator coil according to the embodiment.
The horizontal axis represents the number of cooling / heating cycles, and the horizontal axis represents the value of Δtan δ ₂ where the temperature change of normal temperature −180 ° C.−normal temperature is one cycle. In the figure, the curve of Example 1 is the characteristic curve obtained by the model coil provided with the surface corona preventing layer having the constitution shown in FIGS. 1 and 2, and the curve of Example 2 is the prevention of surface corona preventing having the constitution shown in FIGS. 3 and 4. The characteristic curve obtained with the model coil with layers and the comparative example curve are the characteristic curves obtained with the model coil with the conventional surface corona preventive layer using the semi-conductive fiber tape. Layer thickness is constant voltage 1
The size was made to correspond to the stator coil of a 3.8 kv class high-voltage rotating electric machine. As is apparent from the figure, in the model coils provided with the semiconductive stress relaxation layers in the surface corona preventive layer according to Example 1 and Example 2, the Δtan δ ₂ value was increased even after 3000 thermal cycles. There is no rise in the temperature, and the semi-conductive stress relaxation layer well suppresses the occurrence of peeling due to thermal stress at the main ground insulating layer or at the interface between the main ground insulating layer and the surface corona preventive layer, and the generation of internal partial discharge is effective. It shows that it is suppressing. Contrary to this, in the comparative model coil, Δtan δ was obtained when the heat cycle was 500 times or less.
_The value of ₂ increases sharply, and the surface corona preventive layer does not have the function of suppressing the occurrence of peeling due to thermal stress at the ground main insulating layer or the interface between the ground main insulating layer and the surface corona preventive layer. It shows that partial discharge is occurring, and the above experimental results clearly demonstrated the effect of improving the thermal cycle resistance due to the provision of the semi-conductive stress relaxation layer at the important points of the surface corona prevention layer. .

[0026]

As described above, according to the present invention, the semi-conductive stress relaxation layer for relaxing the stress acting between the ground main insulating layer and the stator core is provided in the stator coil of the high-voltage rotating electric machine by the full impregnation method. The surface corona preventive layer was prepared so as to be provided at the essential points. As a result, the semi-conductive surface corona preventive layer prevents the surface corona from coming into contact with the iron core by conductive contact, and the thermal stress generated by repeated heat and heat cycles is relaxed, and the insulating layer or ground main layer Since it also functions as a thermal stress relaxation function to prevent peeling at the interface between the insulating layer and the surface corona prevention layer, a peeling portion inside the main insulating layer due to thermal stress, which was a problem with the conventional total impregnation type stator coil Therefore, it is possible to prevent discharge deterioration of the main insulating layer against ground due to occurrence of internal partial discharge, and it is possible to provide a stator coil of a high-voltage rotating electric machine excellent in cold-heat cycle resistance.

Further, a semi-conductive rubber layer, a semi-conductive laminer
A semi-conductive stress relaxation layer consisting of either a glass layer or a semi-conductive semi-cured resin layer, and a perforated plastic film such as a semi-conductive fiber tape or a polyester film, a polyimide film, etc. which has been semi-conductive on one side. If a composite semi-conductive tape is used in combination with a base material consisting of, the base material of the surface corona preventive layer functions as a resin impregnating passage to the main insulating layer to ground, and therefore conductive tetrafluoroethylene tape is used. The deterioration of resin impregnation, which was a problem in the conventional stator coil used for the surface corona prevention layer, is prevented, and it contributes to the formation of the void-impregnated main insulating layer with less defects to the ground and the composite semi-conductive tape. A surface corona preventive layer having a stress relaxation function can be easily formed by mechanically winding the cable outside the main insulating layer to ground, thus improving the thermal cycle resistance and insulation reliability. The stator coil of the high voltage rotary electric machine can also be provided advantageously economically that.

Further, when the curing treatment is completed, the semiconductive fiber tape exerts a binding force to prevent the occurrence of peeling at the interface between the main ground insulating layer and the surface corona preventive layer. Therefore, the semiconductive stress relaxation layer is interposed only in the portion facing the side wall surface of the slot where the binding force is difficult to be applied, and there is an advantage that the thermal stress can be effectively relaxed.

[Brief description of drawings]

FIG. 1 is a sectional view showing a stator coil of a high-voltage rotating electric machine according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a surface corona preventive layer portion in an example.

FIG. 3 is a sectional view showing a stator coil of a high-voltage rotating electric machine according to another embodiment of the present invention.

FIG. 4 is an enlarged cross-sectional view showing a surface corona preventive layer in a different embodiment.

FIG. 5 is a characteristic diagram showing a change in dielectric loss angle due to a cooling / heating cycle of a stator coil according to an example.

FIG. 6 is a cross-sectional view showing a main part of a stator coil of a conventional high-voltage rotating electric machine using a full impregnation method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stator coil 2 Shaping coil conductor 3 Ground main insulation layer 4 Surface corona prevention layer 7 Cured material of impregnated resin 9 Slot 10 Stator core 11 Stator coil 12 Semi-conductive fiber tape layer 13 Composite semi-conductive sheet To 13A semi-conductive fiber base material 13B semi-conductive stress relaxation layer 14 surface corona prevention layer 24 surface corona prevention layer

Claims (4)

[Claims] 1. A ground main insulating layer that covers the surface of an aligned coil conductor, and a surface corona preventive layer formed on the outside thereof.
After being inserted into the slots of the stator core, a cured product of a thermosetting impregnating resin impregnated with vacuum pressure is applied to the stator coil integrated with the iron core, whereby the ground main insulating layer and the stator core A stator coil of a high-voltage rotating electric machine, comprising a semi-conductive stress relaxation layer for relaxing stress acting between the core and the surface corona prevention layer. 2. A surface corona preventive layer is provided on the surface of the main insulating layer.
A semi-conductive fiber tape tape layer wound around the layer,
A composite semiconductive sheet interposed between portions of the layers facing the side wall surface of the slot, and the composite semiconductive sheet is semiconductive on one surface of the semiconductive fiber base material. Of a conductive rubber layer, a semi-conductive laminate glass layer, or a semi-conductive semi-cured resin layer is provided with a semi-conductive stress relaxation layer. The stator coil for a high-voltage rotating electric machine according to claim 1, wherein the stator coil is formed to have semiconductivity. 3. A surface corona preventive layer comprising a taped layer of a composite semiconductive tape wound on the surface of a main insulating layer,
This composite semi-conductive tape is a semi-conductive stress relaxation layer consisting of a semi-conductive rubber layer, a semi-conductive laminate glass layer, or a semi-conductive semi-cured resin layer, and the semi-conductive stress relaxation layer. It is made of a composite material with a semiconductive fiber base material that adheres and supports the relaxation layer on one side or both sides thereof, and the surface corona prevention layer is formed so as to have semiconductivity also in the thickness direction. The stator coil of the high-voltage rotating electric machine according to claim 1, wherein 4. A surface corona preventive layer comprising a taped layer of a composite semiconductive tape wound on the surface of a main insulating layer,
This composite semiconductive tape is a base material made of a perforated plastic film having one surface semiconductively treated, and a semiconductive rubber layer formed by closely adhering to the one surface semiconductively treated surface,
It is made of a composite material with a semi-conductive stress relaxation layer consisting of a semi-conductive laminate glass layer or a semi-conductive semi-cured resin layer, and the surface corona preventive layer is provided outside the semi-conductive stress relaxation layer. The stator coil for a high-voltage rotating electric machine according to claim 1, wherein the stator coil is formed on the surface of the main insulating layer by taping.