JP2000224792A - Rotating electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a rotary electric machine compact and reduce the cost by providing a stacked layer of an insulating layer made by attaching inorganic insulations with thermosetting resin and an insulating layer made by diffusing a high temperature conducting filler in the cross insulation and then hardening and setting a product of the initial insulation breakdown voltage and a thermal conductivity within a specified range. SOLUTION: A stator coil 3 consists of a coil conductor 29 constituted of an arrangement of insulated element wires and a main insulation 30 applied to the coil conductor 29. The main insulation 30 is an insulation wound around the coil conductor 29 and is impregnated with resin and is heat-cured. The insulation is a stacked body of a mica layer, a base layer, and a resin layer. The mica layer has a mica foil. The base layer is interwoven with glass fiber. The resin layer is made of such resin as to be impregnated into the mica layer and the base layer and then be hardened, and is filled or mixed with a filler. An amount of the insulator to be filled or mixed in is so controlled that a product of the main insulation breakdown voltage and a thermal conductivity of the stator coil may be between 7 and 20 (MVW/m2.K). Thereby, the machine size and cost can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating electric machine, and more particularly to a rotating electric machine suitable for downsizing a device by improving the thermal conductivity of an insulator.

[0002]

2. Description of the Related Art Conventionally, insulators used for rotating electric machines, for example, those for improving the thermal conductivity of the main insulation of a stator winding are disclosed in CIGTE, 1994 Session, 28-Aug-3 Sep., 11, 101. ,
`` AnImproved Insulation System for the Newest Gene
ration of Stator Windings of Rotating Machines ". In the above, the main insulation is filled with fine-particle insulator having high thermal conductivity such as aluminum oxide to reduce the thermal resistance of the entire stator winding.
Further, Japanese Patent Application Laid-Open No. 63-110929 and Japanese Patent No.
No. 7364 (1987) describes a main insulating material obtained by adding high thermal conductive particles or composite particles and glass fibers to a mica adhesive layer.

Further, an insulating material in which a mica tape and a glass fiber are laminated is described in Japanese Patent No. 411834.

[0004]

However, even if the thermal resistance of the stator winding is reduced as described above, if the thermal load increases with an increase in the power generation capacity, the thermal resistance of the stator winding is reduced. It could not be reduced. When the power generation capacity increases, the voltage generated in the stator winding generally increases,
It is necessary to increase the thickness of the main insulation so as to obtain desired electric insulation characteristics. In particular, when the dielectric breakdown voltage per unit thickness of the main insulation is low, the thickness of the main insulation is increased. Therefore, even if an attempt is made to increase the power generation capacity with the same machine size, the thickness of the main insulation must be increased as described above, and inevitably an increase in the size of the equipment is inevitable.

The present invention has been made in view of the above circumstances, and adjusts the dielectric breakdown voltage and thermal conductivity of the insulating material constituting the main insulating material and other insulating materials to obtain the required thickness of the insulating material. Alternatively, it is an object of the present invention to reduce the volume and reduce the size and cost of the rotating electric machine. Also,
It is an object of the present invention to provide a thermal conductivity measuring method capable of measuring the thermal conductivity of an insulator while the insulator is applied to the conductor.

[0006]

SUMMARY OF THE INVENTION The basic feature of the present invention is that a flake-shaped non-permanent insulating material in which a main insulation constituting a stator winding does not substantially contain a particulate filler is made of a thermosetting resin. It has a laminated body of a bonded first insulating layer, a fibrous cloth insulating material, and a second insulating layer obtained by dispersing and hardening a particulate high thermal conductive filler in a resin, and having an initial dielectric breakdown voltage V of 20 kV. / Mm
As described above, the thermal conductivity λ in the thickness direction of the laminate is 0.35-1.
W / m · K, preferably the product V with 0.5-1 W / m · K
λ is set so that 7 ≦ Vλ ≦ 20 (MVW / m ² · K). 5 W to obtain the above thermal conductivity λ
/ M · K or higher and high thermal conductivity fine particles are filled or mixed with the fiber cloth together with the resin.
Is obtained. The first insulating layer is formed by bonding a high-insulating flaky insulator such as mica, for example, a mica piece, with a thermosetting resin. Substantially no granular hard insulator is added to the first insulating layer so that the flaky insulators are aligned and adhered in layers and prevent the flaky insulators from being broken. This point is based on a completely different idea from the above-mentioned known example.

[0007] The second insulating layer includes a fiber cloth such as a glass fiber. The fiber cloth is necessary for imparting mechanical strength to the insulation motion and for tapering the composite laminate constituting the main insulation. The cloth may be a woven or non-woven cloth. The granular high thermal conductivity insulating material is indispensable for providing high thermal conductivity to the main insulating tape, and a material having 5 W / m / K or more, particularly 30 W · m · K or more is selected. The cloth and the particulate filler are dispersed and cured in a thermosetting resin. The first and second insulating layers are each laminated one or more layers as necessary. The thermal conductivity of this laminate in the thickness direction is 0.3 W / m / K or more, particularly 0.35-1 W.
/ M · K, more preferably 0.5-1 W / m / K. The amount of resin determines the initial breakdown voltage of the laminate. If the amount of the resin is too small, the initial dielectric breakdown voltage of the selected tape becomes insufficient, and if the amount of the resin is too large, the thermal conductivity of the insulating tape becomes insufficient. The amount of resin in the insulation tape is approximately 20 to 50
% By weight is good.

[0008] The insulating material constituting the second insulating layer can also be used as spacer insulation. The amount of the resin and the amount of the filler are adjusted so that the thermal conductivity of the second insulating layer is 0.35-1 W / m · K and the initial breakdown voltage is 20 kV or more.

In order to satisfy the above-mentioned Vλ, the amount of the insulating material added to the resin is adjusted to secure the necessary thermal conductivity.
Make sure that the dielectric breakdown voltage does not decrease. Thus, V
When a stator winding composed of main insulation with λ set in the above range is used for a rotating electric machine, in the case of a rotating electric machine that cools the inside of the machine with hydrogen, the square of the diameter of the rotor with respect to the power generation capacity per number of rotations is fixed. The ratio of the product to the axial length of the child is 40 m ³ · r
pm / MVA or less, and the ratio of the product of the square of the rotor diameter to the length between the supports of the rotating shaft to the power generation capacity per rotation speed is 50 m ³ · rpm / MVA or less. In the case of a rotating electric machine that cools the inside of the machine with air, the ratio of the product of the square of the diameter of the rotor to the shaft length of the stator to the power generation capacity per number of rotations is 70 m ³ · rpm / MVA or less. The ratio of the product of the square of the rotor diameter to the capacity and the length between the supports of the rotating shaft is less than 85 m ³ · rpm / MVA.

Further, the present invention provides a spacer for interposing an insulator having a thermal conductivity of 5 W / m · K or more between the windings at the end portion of the stator winding, and an insulator constituting the rotor, for example, a slot insulation. Or the insulating block or the retaining ring insulation is filled or mixed to improve the thermal conductivity of the rotating electric machine.

Further, the present invention can be applied to an insulated wire having a tape woven with fibers of an inorganic or organic material as a base material, and an insulator having a thermal conductivity of 5 W / m · K or more can be used in an insulating resin. To improve or improve the thermal conductivity of the insulated wire. The main insulation is a fine, fibrous, or flaky insulating material having a thermal conductivity of 5 W / m · K or more, alone or in combination, filled or mixed into a thermosetting resin or a thermoplastic resin, and used as an insulating material. Has an initial breakdown voltage of 20 kV / mm or more and a thermal conductivity of 0.35
It is formed so as to be 1 W / m · K. 5W
/ M · K or more is filled or mixed with a thermosetting resin, a thermoplastic resin, or a rubber in the form of fine or fibrous insulator having a heat conductivity of not less than 0.35 W / m · K. An insulating material may be formed and used as a spacer between the windings at the end of the stator winding.

According to the present invention, the heat insulating block member is brought into contact with an object to be measured formed on a rotating electric machine or the like, and a heating wire or a foil heater or a heating member combining them is brought into contact with one plane or one surface of the heat insulating block member. The block member is heated by the heating member, and the thermal conductivity of the measured object is measured by measuring the temperature change of the block member.

The thermal conductivity used in the present invention is 5 W
Examples of the insulating material having a high thermal conductivity of not less than / m · K include boron nitride, aluminum nitride, silicon nitride, aluminum oxide, magnesium oxide, beryllium oxide, and silicon carbide. In particular, aluminum oxide, boron nitride, magnesium oxide, or the like having a thermal conductivity of 30 W / m / K or more and a volume resistance of 10 ¹³ Ωcm or more is preferable. These are used in the form of particles having an average particle diameter of 20 μm or less. Insulating materials based on glass fibers or other organic or inorganic fibers are known, and these fibers are mixed in the resin together with the granular insulating material.

Since a high dielectric breakdown voltage is required for the main insulation, an insulating material in which a flaky inorganic material is bonded with an adhesive resin (this particularly shares the withstand voltage) and one or both of the fibers or particles are used. A composite insulating material obtained by laminating an insulating material dispersed in a resin is used. When a slightly brittle inorganic insulating material such as mica is used as a flaky insulator, the particles and fibers should not be mixed into the insulating layer as much as possible. When mixed, the flaky mica cannot be arranged in a layered form, and the dielectric strength decreases, and the mica may be destroyed to lower the dielectric strength.

An insulating material formed by dispersing short fibers or particles in a resin is used as an insulating material such as a spacer which does not require much withstand voltage as compared with the main insulating material. The fibrous filler can be filled in the form of woven fabric, nonwoven fabric or short fiber such as glass cloth. The fiber cloth is a necessary material to maintain the mechanical strength of the spacer. Such an insulating material can be used even if a plurality of layers are laminated. In particular, when a woven fabric such as a glass cloth is used, the insulating material is laminated to a required thickness.

The amount of the resin in the first insulating layer and the second insulating layer is preferably 10 to 25% by weight of the total amount of the resin and the filler. When the amount of the resin is less than 10% by weight, the thermal conductivity of the insulating material increases, but the withstand voltage becomes insufficient. Since the main insulation of a large-capacity rotating electric machine requires a withstand voltage of 20 kV / mm or more, the amount of resin is set to 10% by weight or more in order to ensure a sufficient dielectric strength.

On the other hand, if the amount of the resin exceeds 25% by weight, the amount of the high thermal conductive filler is insufficient, the thermal conductivity of the insulating material becomes insufficient, the main insulating layer needs to be thickened, and the equipment becomes large. Become In the laminated insulating material having the first and second insulating layers, the amount of the resin to the filler + the resin is 20 to 5%.
0% by weight is preferred.

The resin used in the present invention includes:
The main insulation mainly uses a thermosetting resin such as an epoxy resin, an unsaturated polyester resin, an alkyd resin, and a polyamide resin. When the insulating material proposed by the present invention is used as the spacer, a thermoplastic resin such as a saturated polyester resin or a rubbery acrylic butadiene copolymer can be used.

As a method for forming the main insulation on the conductor of the rotating electric machine, a conventionally known method can be used, and details will be described in the embodiments.

[0020]

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

1 to 3 show the structure of the turbine generator according to the present embodiment. In the figure, reference numeral 1 denotes a stator frame. A stator core 2 is provided on the inner peripheral side of the stator frame 1. FIG.
As described above, the stator core 2 has a cylindrical shape formed by laminating a plurality of core blocks 14 formed by laminating a plurality of thin ring-shaped silicon steel plates and a plurality of spacers 16 arranged at a constant pitch in the circumferential direction. Things. Thus, spacer 1
By laminating a plurality of silicon steel plates through the steel plate 6, a plurality of ventilation ducts 17 communicating with the stator core 2 in the radial direction can be formed in the circumferential direction and the axial direction.

A plurality of axially continuous slots 18 are provided on the inner peripheral surface side of the stator core 2 in the circumferential direction. Each of the slots 18 houses the stator winding 3. As shown in FIG. 2, each of the slots 18 has a rectangular cross section which is vertically elongated in the radial direction, and the stator windings 3 are accommodated therein in a state of being stacked in two stages in the radial direction via an insulator 19. ing. Each of the slots 18 is open on the inner peripheral surface side of the stator core 2. Therefore, the stator windings 3 housed on the inner peripheral surface side of the stator core 2 with respect to the stator windings 3 of the slots 18 are prevented from protruding from the respective slots 18 so that the stator windings 3 are not protruded from the respective slots 18. After the storage, the wedge 20 is inserted through the insulator 19. The configuration of the stator winding 3 itself will be described later.

A rotor core 4 is rotatably provided on the inner peripheral side of the stator core 2 through a gap, a so-called air gap. The rotor core 4 is formed by integrally forming a rotation shaft 7. The rotating shaft 7 extends in the axial direction from the center of both end surfaces of the rotor core 4, and is rotatably supported by a bearing device 8 provided on the inner peripheral side of an end bracket 10 that covers both ends of the stator frame 1. Fans 9 are provided at both ends of the rotor core 4 of the rotating shaft 7. The fan 9 rotates together with the rotating shaft 7 and circulates the cooling medium sealed in the machine.

A plurality of axially continuous slots 21 are provided on the outer peripheral surface side of the rotor core 4 in the circumferential direction. A subslot 27 communicating with the axial direction is provided on the bottom side of each of the slots 21. A plurality of ventilation slots 28 are provided between the slots 21 to communicate the sub-slots 27 and the outer peripheral surface of the rotor core 4. Each of the slots 21 accommodates the rotor winding 5. As shown in FIG. 3, each of the slots 21 has a rectangular cross section that is vertically elongated in the radial direction. The rotor winding 5 is formed by alternately laminating a plurality of rectangular winding conductors 22 and turn insulations 23 in the radial direction.

A slot insulation 24 is arranged between the rotor winding 5 and the slot 21. Each of the slots 21 is open on the outer peripheral surface side of the rotor core 4. For this reason, the stored rotor windings 5 are located closer to the outer peripheral surface of the rotor core 4 than the respective rotor windings 5 of the slots 21 so that the stored rotor windings 5 do not jump out of the respective slots 21. After the rotor winding 5 is housed, the wedge 26 is inserted through the insulating block 25 so that the wedge 26 does not protrude from each of the slots 21. Both ends of the rotor winding 5 are firmly fixed at both ends of the rotor core 4 by a retaining ring 6 via a retaining ring insulation.

In the space between the stator frame 1 and the stator core 2, a plurality of coolers 11 are provided. The cooler 11 is provided for cooling a cooling medium, for example, air or hydrogen enclosed in the machine. A current collector 12 for supplying electric power to the rotor winding 5 is connected to one end of the rotating shaft 7. The current collector 12 supplies electric power to the rotating rotor winding 5 by pressing a carbon brush on the outer peripheral surface of a slip ring that is connected to the rotor winding 5 and rotates together with the rotating shaft 7. Electric power obtained by the power generation is taken out from a terminal 13 provided outside the stator frame 1.

Next, a cooling method according to the present embodiment will be described. In the present embodiment, the inside of the machine is cooled by circulating cooling water inside the stator winding 3 or circulating a cooling medium such as air or hydrogen sealed inside the machine by the fan 9. Specifically, in the former, the winding conductor of the stator winding 3 is hollow, a box called a clip is attached to both ends of the stator winding 3, cooling water is supplied from one clip, and the cooling water is supplied. The cooling is performed by flowing through the inside of the stator winding 3 and the cooling water that has been cooled is discharged from the clip on the other side.

In the latter, a cooling medium such as air or hydrogen sealed in the machine is cooled by a cooler 11, and the cooled cooling medium is circulated inside the machine by a fan 9 to cool each part. . In more detail, the cooling medium cooled by the cooler 11 is
The air gap between the stator core 2 and the rotor core 4, the air gap between the stator core 2 and the rotor core 4, It is led to space and cools each part. The arrows in FIGS. 2 and 3 indicate the flow of the cooling medium.

The cooling medium introduced between the rotor winding 5 at the end of the rotor core 4 and the rotating shaft 7 cools the end of the rotor winding 5. The cooling medium that has cooled the end of the rotor winding 5 flows through the sub-slot 27 and the ventilation slot 28, and
Is cooled from the inside. The cooling medium that has cooled the rotor core 4 is guided to an air gap between the stator core 2 and the rotor core 4.

The cooling medium guided to the air gap cools the inner peripheral side of the stator core 2 and the outer peripheral side of the rotor core 4.
The cooling medium that has cooled them merges with the cooling medium guided from the inside of the rotor core 4 to the air gap, and flows through the ventilation duct 17 to cool the stator core 2 from the inside. The cooling medium that has cooled the inside of the stator core 2 flows through the space between the stator frame 1 and the stator core 2 and is cooled by the cooler 11.

The cooling medium guided to the space of the coil end portion of the stator winding 3 cools the coil end portion of the stator winding 3 and circulates through the ventilation path extending to the outer peripheral side of the stator core 2 to be fixed. It is guided to the outer peripheral side of the core 2. The cooling medium guided to the outer peripheral side of the stator core 2 flows through the ventilation duct 17 to cool the stator core 2 from the inside. The cooling medium that has cooled the stator core 2 from the inside is guided to the air gap, merges with the cooling medium guided to the above-described air gap, and has a ventilation duct 17, a space between the stator frame 1 and the stator core 2. And cooled by the cooler 11.

In this embodiment, an example has been described in which the cooling medium enclosed in the machine is cooled by a cooler provided inside the machine. However, the cooling medium cooled by a cooler provided outside the machine is sent into the machine, After cooling, a method may be used in which the cooling medium is collected, cooled by a cooler, and sent back into the machine.

Next, the structure of the stator winding 3 will be described in more detail. FIG. 4 shows the structure of the stator winding 3 of the present embodiment. The stator winding 3 is provided on a winding conductor 29 formed by arranging m-rows and n-columns (m and n are arbitrary integers) by arranging strands of a rectangular cross-sectional shape subjected to strand insulation. The main insulation 30 is formed. The main insulation 30 is formed by winding a tape-shaped or sheet-shaped insulating material around the outer periphery of the winding conductor 29 a plurality of times, impregnating with resin, and heating and curing the resin. The number of windings of the tape-shaped or sheet-shaped insulating material is determined by the thickness of the main insulation 30, that is, the degree of the obtained electric insulation resistance. A corona shield for preventing corona discharge is wound on the outermost periphery of the main insulation 15.

Next, the structure of the insulating material forming the main insulation 15 will be described. FIG. 5 shows the structure of the insulating material of the present embodiment. The insulating material is a laminate of the mica layer 31, the base material layer 32, and the resin layer 33. The mica layer 31 secures the electrical insulation strength and has a mica foil. Base material layer 32
Is to ensure mechanical strength and is woven with glass fiber. The resin layer 33 is made of a resin which is impregnated and cured in the mica layer 31 and the base material layer 32, and has a filler filled or mixed therein.

The filler is an electrical insulator such as aluminum oxide or aluminum nitride having a thermal conductivity of 5 W / m · K or more, and is in the form of fine particles having high thermal conductivity, short fibers or flakes. The base layer 32 may be a state in which fibers such as aluminum oxide or aluminum nitride are woven into a cloth. Further, the resin layer 33 may be laminated on the base layer 32 side, may be laminated on the mica layer 31 side, or may be on both sides.

The above-mentioned insulating material is manufactured as follows. Hereinafter, one embodiment will be described. First, a laminated mica foil (having a weight of 165 g / m ² ) and a glass cloth (having a weight of 35) were produced by forming a mica particle dispersed in water by paper machine.
g / m ² ), and impregnated with a resin (impregnation amount 85 g / m ² ) obtained by adding 3 parts by weight of BF ₃ monoethylamine to 100 parts by weight of a novolak-type epoxy resin, and bonding and bonding. (A laminate comprising the mica layer 31 and the base material layer 32) is obtained.

Thereafter, a resin obtained by adding 3 parts by weight of BF ₃ monoethylamine to 100 parts by weight of the novolak-type epoxy resin was mixed with the aluminum oxide particles at a weight ratio of the aluminum oxide particles to the resin of 2: 1 and then 10% by weight of methyl ethyl ketone was added thereto.
The coated mica sheet is coated on the side surface of the base material layer 32 by a roll coater so that the coating amount is 256 g / m ² .

Thereafter, the methyl ethyl ketone is volatilized and removed in a drying furnace to obtain a sheet-like insulating material. In order to obtain a tape-shaped insulating material, it is obtained by slitting a sheet-shaped insulating material to a width of 30 mm. The tape-shaped insulating material obtained as described above is also called a prepreg tape, and the amount of resin contained therein is 31.4% by weight of the whole insulating material,
The amount of resin contained in the mica layer 31 is 1% of the entire insulating material.
2.9% by weight, the amount of resin contained in the base material layer 32 was 15.0% by weight of the whole insulating material.
9

First, the tape-shaped insulating material obtained as described above is partially overlapped and wound around the outer periphery of the winding conductor 29. Thereafter, a release tape is wound around the outer peripheral side of the insulating material. Thereafter, a molding jig is attached to the periphery, an external force is applied from the outer surface through the molding jig, and a part of the resin contained in the insulating material is heated at a predetermined temperature while discharging the resin. The resin contained in the is cured. Thereby, the main insulation 30 is formed on the outer peripheral side of the winding conductor 29, and the stator winding 3 is obtained.

Next, the relationship between the machine size and the product Vλ of the dielectric breakdown voltage V of the main insulation of the stator winding and the thermal conductivity λ will be described. FIG. 6 shows the main stator winding when the product Vλ = 5 (MVA / m ² · K) of the breakdown voltage V of the main insulation of the stator winding and the thermal conductivity λ is 100% (reference). The relation between the machine size and the product Vλ of the insulation breakdown voltage V and the thermal conductivity λ is shown. In FIG. 6, a solid line 34 indicates a case where hydrogen is used for cooling the inside of the device, and a solid line 35 indicates a case where air is used for cooling the inside of the device. Here, the breakdown voltage V and the thermal conductivity λ
The product Vλ of this expression means V / (1 / λ) = (insulation resistance) / (thermal resistance), and as apparent from FIG.
When the product Vλ of the heat conductivity and the thermal conductivity λ is increased, the machine size is reduced.

The main insulation of the stator winding needs to have a sufficient thickness so as not to cause insulation breakdown with respect to the generated voltage. However, the main insulation of the stator winding obtained as described above is required. Since the insulation can have an initial breakdown voltage V of 20 kV / mm or more, for example, the minimum required main insulation thickness δ for a generated voltage of 20 kV is 20 kV / (20 kV / mm).
V / mm) = 1 mm. It should be noted that the breakdown voltage of the main insulation decreases according to the operating years, so the thickness of the main insulation must be determined in consideration of the safety margin.

The main insulation of the stator winding obtained as described above is in the form of high heat conductive fine particles, such as aluminum oxide or aluminum nitride, having a heat conductivity of 5 W / m · K or more, short fibers or flakes. Is filled or mixed, and its thermal conductivity can be 0.3 W / m · K or more. Note that the thermal conductivity of the main insulation is preferably large in terms of cooling.However, if the filling amount or mixing amount of an insulator such as aluminum oxide or aluminum nitride is excessively increased in order to increase the thermal conductivity, the mica layer and the The ratio of the resin layer that protects the base material layer and secures the strength is reduced, and the mechanical strength is reduced. Further, the thermal resistance due to the heat transfer of the cooling medium becomes relatively large, and even if the thermal conductivity λ is increased, the reduction rate of the temperature rise of the stator winding becomes small.

From the above, in the present embodiment,
The product Vλ of the dielectric breakdown voltage V of the main insulation of the stator winding and the thermal conductivity λ is 7 ≦ Vλ ≦ 20 (MVW / m ² · K), and the thermal conductivity λ is 0.3 W / m · K or more. 5W / m · K
The filling amount or mixing amount of the high thermal conductive fine particle, short fiber, or flaky insulator such as aluminum oxide or aluminum nitride having the above thermal conductivity is adjusted.

In addition, the initial insulation breakdown voltage V of the main insulation of the stator winding obtained as described above is 20 kV / mm or more, and considering the minimum value of 20 kV / mm, the main winding of the stator winding is The thermal conductivity λ in the thickness direction of the insulation is 0.35 ≦ λ ≦ 1
(W / m · K). Further, considering the safety margin due to the variation of the temperature distribution, the thermal conductivity λ of the main insulation of the stator winding is preferably set to 0.5 ≦ λ ≦ 1 (W / m · K).

Next, the AC breakdown voltage test results of the electric winding of this embodiment and the electric winding of the comparative example will be described with reference to Table 1. As the electric winding of the comparative example, an electric winding having high heat conduction insulation formed of a high heat conduction insulating tape manufactured as follows was used. The production of the high heat conductive insulating tape is as follows.

First, a laminated mica foil 2 (having a weight of 165 g /
m ² ) and glass cloth 4 (weight 35 g / m ² )
These are impregnated with a resin (impregnation amount 40 g / m ² ) obtained by adding 3 parts by weight of BF ₃ monoethylamine to 100 parts by weight of a novolak type epoxy resin, and adhered to each other to form a mica sheet (mica layer 3 and reinforcing material layer 5). To obtain a laminate).

Thereafter, BF ₃ monoethylamine 3 was added to 100 parts by weight of the alumina particles and the novolak type epoxy resin.
The resin added by weight is mixed so that the weight ratio of the alumina particles to the resin is 3.5: 1, 10% by weight of methyl ethyl ketone is added thereto, and a roll coater is applied to the side of the reinforcing material layer of the mica sheet. Was applied so that the coating amount was 230 g / m ² . Thereafter, methyl ethyl ketone was volatilized and removed in a drying furnace to obtain a high heat conductive insulating sheet. Thereafter, the high heat conductive insulating sheet 1 was slit into a 30 mm wide slit with a slitter.

In the high heat conductive insulating tape of the comparative example thus manufactured, the total amount of resin therein was 19.3% by weight of the whole high heat conductive insulating tape. The amount of resin in the mica layer was 7.1% by weight of the entire high thermal conductive insulating tape, and the amount of resin in the high thermal conductive filler layer was 10.4% by weight of the entire high thermal conductive insulating tape.

Thereafter, an electric winding was manufactured using the high thermal conductive insulating tape manufactured as described above. The manufacturing method is the same as that of the present embodiment, and the description is omitted.

In the AC breakdown voltage test, aluminum foil was wound around the outer periphery of each of the electric winding of the present embodiment and the electric winding of the comparative example to form electrodes. An AC voltage was applied in between, and the AC breakdown voltage was measured. The result was as shown in Table 1.

[0051]

[Table 1]

As is evident from Table 1, the electric machine winding of the present example had a higher AC breakdown voltage than the electric motor winding of the comparative example. This is because the mica is layered without any defect and the amount of resin in the high thermal conductive filler layer is within the range of 10 to 25% by weight of the entire material. Is formed. When forming the high thermal conductive insulating coating of the electric winding, in the pressing process,
This is because minute bubbles contained in the high heat conductive insulating tape could be sufficiently discharged together with a part of the resin in the high heat conductive insulating tape.

Therefore, the electric motor winding of the present embodiment has a dense and high heat conductive insulating coating having excellent electric characteristics.
High reliability can be provided for a rotating electric machine operated at a high voltage.

Next, the effect of reducing the temperature rise when using the stator winding of the present embodiment in which the product Vλ of the dielectric breakdown voltage V of the main insulation and the thermal conductivity λ is set as described above will be described. .
FIG. 7 is a graph showing the effect of reducing the temperature rise, which can be compared with the prior art. In FIG. 7, rod 3
Reference numeral 7 denotes a case in which hydrogen is used for cooling the inside of the device, and the temperature rise is reduced by 30% or more compared to the conventional technology. Here, the heat value of the stator winding is 30% since it is proportional to the square of the current.
The above reduction reduces the armature current of the stator winding by √1.3 = 1.15.
This means that the output can be increased without changing the ventilation cooling structure. Therefore, the output can be increased by replacing the stator windings with the stator windings of the present embodiment not only in newly installed facilities but also in conventional power generation facilities.

The rod 38 is a case where air is used for cooling the inside of the machine, and is reduced by 15% or more as compared with the prior art. This case can be considered in the same manner as described above. Therefore, 15
% Or more reduces the armature current of the stator winding by √1.15 = 1.
This means that the output can be increased by a factor of 07, and the output can be increased without changing the ventilation cooling structure as described above.

Next, the relationship between the power generation capacity of the turbine generator and the machine size will be described. FIG. 8 shows the product of the square of the rotor diameter and the axial length of the stator with respect to the power generation capacity per rotation speed (horizontal axis), that is, the volume of the portion related to power generation (vertical axis). In addition, in the case where air is used for cooling the inside of the machine and the case where hydrogen is used, the use of hydrogen has higher thermal conductivity and specific heat, so that the cooling capacity is higher, and a large power generation capacity can be achieved even with the same machine size. The machine size is proportional to the power generation capacity per rotation.

When hydrogen is used for cooling the inside of the apparatus, the solid line 40
And the ratio of the product of the square of the rotor diameter to the shaft length of the stator to the power generation capacity per number of rotations is 40 m ³ · rpm
/ MVA or less. When air is used for cooling the inside of the machine, the solid line 41 shows the ratio of the product of the square of the rotor diameter and the shaft length of the stator to the power generation capacity per rotation speed of 70 m ³ · rpm / MVA or less. can do.

As described above, in the present embodiment, the air-cooled generator of more than 150 MVA and 300 MVA class and the hydrogen cooling of more than 200 MVA and 500 MVA class while suppressing the increase of mechanical loss including friction loss with the fluid on the rotor surface. A generator can be realized. Note that a machine size of 7 m ³ or more causes a large increase in the temperature of the cooling fluid due to mechanical loss, so that it is difficult to realize a turbine generator with a practical machine size. That is, the broken line 39 is the limit.

The relationship shown in FIG. 8 is represented by the ratio of the product of the square of the diameter of the rotor and the length between the supports of the rotating shaft (the distance between the bearing supports) to the power generation capacity per number of rotations. 50 m ³ · rpm / MVA or less when hydrogen is used for cooling the inside of the machine, and 85 m ³ · rpm / M when air is used for cooling the inside of the machine.
VA or less.

Next, the configuration of the insulator when the above-described configuration of the insulator is applied to another insulator in the turbine generator will be described. FIG. 9 shows the configuration of another insulator in the turbine generator. Here, the other insulator is a slot insulator 2
4, insulating blocks 25, retaining ring insulation, spacers sandwiched between the windings of the coil ends of the stator windings 3, and the like. These insulators are a laminate formed by laminating a plurality of resin layers 33 and a base layer 32 in which glass fibers are woven, and the resin layers 33 are made of aluminum oxide or aluminum oxide having a thermal conductivity of 5 W / m · K or more. Highly heat-conductive fine particles or short fiber-like or flake-like insulators such as aluminum nitride are filled or mixed.

In this embodiment, as described above, 5 W / m ·
Since the resin layer 33 is filled with or mixed with a highly thermally conductive fine particle, short fiber, or flaky insulator such as aluminum oxide or aluminum nitride having a thermal conductivity of K or more, the slot insulation 24, the insulation block 25, It is possible to improve the retaining ring insulation and the thermal conductivity of a spacer or the like sandwiched between the windings of the coil end portion of the stator winding 3. As described above, when the thermal conductivity of each insulator is improved, for example, when the thermal conductivity of the slot insulation 24 and the insulating block 25 is improved, the temperature of the rotor winding 5 can be reduced. If the thermal conductivity is about twice that of the conventional model, the temperature rise can be reduced by about 30%, and the output of the turbine generator can be reduced by about 1.3%.
= 1.15 times increase.

Further, when there is room for the stator temperature rise, when the rotor winding is renewed in the preventive maintenance of the turbine generator, the above-mentioned slot insulation is used to renew the rotor winding.
An output increase of about 5% can be achieved. Although it can be used for a direct cooling rotor, the cooling rate of the direct cooling rotor via slot insulation is low, so that the temperature reduction effect of the field winding is about 10%.
In the case where air is used for cooling the inside of the machine, this effect is further reduced due to the thermal resistance of air in the gap between the slot insulation and the slot or between the slot insulation and the rotor winding.

Next, an embodiment of the insulated wire according to the present invention will be described. 10 to 14 show the structure of the insulated wire of the present embodiment. The insulated wire is used for an exciter for a rotor, a stator winding for a motor, and the like, which are one of the main components of a turbine generator.
1 having an insulating coating formed by the insulating material shown in FIG.
It has a round cross-sectional shape such as 0 or a rectangular cross-sectional shape as shown in FIG.

In the figure, reference numeral 42 denotes a conductor made of a single wire or a stranded wire. The stranded wire is provided with an insulating coating for each strand according to the purpose of use. An insulating coating 43 is provided on the outer periphery of the conductor 42.
Has been given. The insulating coating 43 is made of a resin 44, a base material 45 filled or mixed in the resin 44, and a filler filled or mixed in a gap between fibers of the base material 45. Base material 4
Numeral 5 is for securing the mechanical strength of the insulating material, and is a tape-like material in which fibers of an inorganic material or an organic material are woven. The filler is a highly thermally conductive fine particle or flake-like insulator such as aluminum oxide having a thermal conductivity of 5 W / m · K or more. Note that the base material 45 may be a roving material (a long fiber shape) as shown in FIG. 13 or a short fiber shape as shown in FIG.

According to the present embodiment, as described above,
Since the insulator having a high thermal conductivity is filled or mixed in the gap between the fibers of No. 5, the thermal conductivity of the insulating coating can be improved. Although a glass fiber cloth is often used for the base material 45, if a fiber cloth such as aluminum oxide is used from the beginning, the insulating coating can be easily performed without filling or mixing the insulating material having high thermal conductivity into the base material 45. Can be improved in thermal conductivity.

Next, an embodiment of the thermal conductivity measuring method according to the present invention will be described. FIG. 15 shows an apparatus configuration for carrying out the thermal conductivity measuring method of the present embodiment. Specifically, a measurement state of the thermal conductivity of the main insulation of the stator winding used in the turbine generator Is shown. The thermal conductivity measuring method of the present embodiment is an application of the unsteady hot wire method, and can be measured in a state where the main insulation 30 is applied to the winding conductor 29. Hereinafter, the thermal conductivity measuring method of the present embodiment will be described in detail.

First, two heating members 47 such as a hot wire or a foil heater are stuck on one side of the heat insulating block 46 in parallel. Here, the heat insulating block 46 is formed of a material having isotropic thermal conductivity. The thermal conductivity of the heat insulating block 46 is measured in advance by the steady heat flow method. After that, a temperature sensor 48 such as a thermocouple is arranged at the center of the heating member 47. In the present embodiment, a combination of the heat insulating block 46, the heating member 47, and the temperature sensor 48 will be referred to as a heat conduction measuring head.

When the heat transfer measuring head is ready,
The heat conduction measuring head is pressed against the side section of the stator winding 3 which is the object to be measured, and is brought into contact therewith. After this, the pulse generator 4
The pulse signal generated from 9 and amplified by the amplifier 50 is applied to one heating member 47 to heat the heating member 47 transiently. Then, the temperature change at this time is detected by the temperature sensor 48 and measured by the measuring device 51. The measuring instrument 51 is described in Transactions of the Opportunity Society of Japan (B), Vol. 48, No. 433 (Showa 5).
7-9), pp. 1743-1749, the combined thermal conductivity in the thickness direction of the insulator and the plane on which the thermal conductivity measuring head is pressed is measured.

After the above measurement is completed, both heating members 47 are heated, and the temperature change at this time is detected by the temperature sensor 48 and measured by the measuring device 51. According to this method, the heat flow in the plane direction of the insulator sandwiched between the two heating members 47 decreases, and the heat flow in the thickness direction of the insulator increases, so that the dominant thermal conductivity in the thickness direction of the insulator increases. Measured. Therefore, the thermal conductivity of the main insulation 30 can be measured in a state where the main insulation 30 is applied to the winding conductor 29.

Further, before the measurement, a transient temperature analysis is performed in the case where the heating member generates heat for various substances, and the thermal conductivity that best represents the temperature distribution in both the above-described measurements is obtained from a parameter survey. When the thermal conductivity of the main insulation is measured, whether the machine size can be reduced can also be verified at the same time.

[0071]

According to the rotating electric machine according to the present invention, the thermal conductivity is improved while sufficiently maintaining a high initial insulation breakdown voltage of the main insulation of the stator winding, thereby reducing the thickness of the main insulation and the like. And the temperature rise of the equipment can be suppressed.
Therefore, it is possible to reduce the machine size and the cost.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a turbine generator according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a configuration of a stator side of FIG. 1;

FIG. 3 is a sectional view showing a configuration of a rotor side of FIG. 1;

FIG. 4 is a perspective view showing a structure of a stator winding of FIG. 2;

FIG. 5 is a cross-sectional view showing a configuration of an insulating material used for forming main insulation of FIG.

FIG. 6 is a diagram illustrating a relationship between a machine size and a product Vλ of a dielectric breakdown voltage V of a main insulation of a stator winding and a thermal conductivity λ.

7 is a diagram showing a temperature rise reduction effect when main insulation of the stator winding of FIG. 4 is formed by using the insulating material of FIG. 5;

8 is a diagram illustrating the relationship between the power generation capacity of the turbine generator and the machine size when main insulation of the stator winding of FIG. 4 is formed using the insulating material of FIG. 5;

9 is a diagram showing a configuration of an insulator (for example, an insulating block) when the configuration used for the insulating material in FIG. 5 is applied to another insulator in the turbine generator.

FIG. 10 is a perspective view showing a configuration of an insulated wire having a round cross-sectional shape according to an embodiment of the present invention.

FIG. 11 is a perspective view showing a configuration of an insulated wire having a rectangular cross-sectional shape according to an embodiment of the present invention.

FIG. 12 is a cross-sectional view showing one configuration of the insulating coating of FIG. 10 or FIG.

FIG. 13 is a sectional view showing one configuration of the insulating coating of FIG. 10 or FIG. 11;

FIG. 14 is a cross-sectional view showing one configuration of the insulating coating of FIG. 10 or FIG.

FIG. 15 is a state diagram illustrating a device configuration for performing the thermal conductivity measuring method, which is for describing the thermal conductivity measuring method according to the embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Stator frame, 2 ... Stator core, 3 ... Stator winding, 4 ...
Rotor core, 5 ... rotor winding, 6 ... retaining ring,
7 ... rotating shaft, 8 ... bearing device, 9 ... fan, 10 ... end bracket, 11 ... cooler, 12 ... current collector, 13 ... terminal, 29 ... winding conductor, 30 ... main insulation, 31 ... mica layer, 32: base material layer, 33: resin layer, 42: conductor, 43
... insulating coating, 44 ... resin, 45 ... base material, 46 ... heat insulating block, 47 ... heating member.

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] October 8, 1999 (1999.10.
8)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 12

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0001

[Correction method] Change

[Correction contents]

[0001]

The present invention relates to relates to a rotary electric machine, and more particularly suitable for rotary electric machine in compact equipment by the upper heat conduction RitsuMuko insulator.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

[0007] The second insulating layer includes a fiber cloth such as a glass fiber. The fiber cloth is necessary to provide mechanical strength to the insulating layer and to tape the composite laminate constituting the main insulation. The cloth may be a woven or non-woven cloth. The granular high heat conductive insulating material is indispensable for giving high heat conductivity to the main insulating tape, and a material having a power of 5 W / m · K or more, particularly 30 W / m · K or more is selected. The cloth and the particulate filler are dispersed and cured in a thermosetting resin. The first and second insulating layers are each laminated one or more layers as necessary. The thermal conductivity in the thickness direction of this laminate is 0.3 W / m · K or more, particularly 0.35-1 W
/ M · K, more preferably 0.5-1 W / m · K, the amount of the resin is selected. The amount of resin determines the initial breakdown voltage of the laminate. If the amount of the resin is too small, the initial dielectric breakdown voltage of the selected tape becomes insufficient, and if the amount of the resin is too large, the thermal conductivity of the insulating tape becomes insufficient. The amount of resin in the insulation tape is approximately 20 to 50
% By weight is good.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction contents]

The thermal conductivity used in the present invention is 5 W
Examples of the insulating material having a high thermal conductivity of not less than / m · K include boron nitride, aluminum nitride, silicon nitride, aluminum oxide, magnesium oxide, beryllium oxide, and silicon carbide. In particular, aluminum oxide, boron nitride, magnesium oxide, or the like having a thermal conductivity of 30 W / m · K or more and a volume resistance of 10 ¹³ Ωcm or more is preferable. These are used in the form of particles having an average particle diameter of 20 μm or less. Insulating materials based on glass fibers or other organic or inorganic fibers are known, and these fibers are mixed in the resin together with the granular insulating material.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0019

[Correction method] Change

[Correction contents]

As a method of forming the main insulation on the conductor of the rotating electric machine, a conventionally known method can be used, and the details will be described in Examples.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0040

[Correction method] Change

[Correction contents]

Next, the relationship between the machine size and the product Vλ of the dielectric breakdown voltage V of the main insulation of the stator winding and the thermal conductivity λ will be described. FIG. 6 shows the stator winding when the product Vλ = 5 (MV W / m ² · K) of the dielectric breakdown voltage V of the main insulation of the stator winding and the thermal conductivity λ is 100% (reference). The relationship between the machine size and the product Vλ of the breakdown voltage V of the main insulation and the thermal conductivity λ is shown. In FIG. 6, a solid line 34 indicates a case where hydrogen is used for cooling the inside of the machine, and a solid line 35 indicates a case where air is used for cooling the inside of the machine. Here, the breakdown voltage V and the thermal conductivity λ
The product Vλ of this expression means V / (1 / λ) = (insulation resistance) / (thermal resistance), and as apparent from FIG.
When the product Vλ of the thermal conductivity λ and the thermal conductivity λ is increased, the machine size is reduced.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0057

[Correction method] Change

[Correction contents]

When hydrogen is used for cooling the inside of the apparatus, a solid line 41
And the ratio of the product of the square of the rotor diameter to the shaft length of the stator to the power generation capacity per number of rotations is 40 m ³ · rpm
/ MVA or less. When air is used for cooling the inside of the machine, the solid line 40 shows, and the ratio of the product of the square of the rotor diameter to the shaft length of the stator with respect to the power generation capacity per rotation speed is 70 m ³ · rpm / MVA or less. can do.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

When the heat transfer measuring head is ready,
The heat conduction measuring head is pressed against the side section of the stator winding 3 which is the object to be measured, and is brought into contact therewith. After this, the pulse generator 4
The pulse signal generated from 9 and amplified by the amplifier 50 is applied to one heating member 47 to heat the heating member 47 transiently. Then, the temperature change at this time is detected by the temperature sensor 48 and measured by the measuring device 51. Instrument 51 Japan Machinery Society Papers (B eds), Vol. 48, No. 433 (Sho 5
7-9), pp. 1743-1749, the combined thermal conductivity in the thickness direction of the insulator and the plane on which the thermal conductivity measuring head is pressed is measured.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Saburo Usami 502 Kandate-cho, Tsuchiura-shi, Ibaraki Pref. Machinery Research Laboratory, Hitachi, Ltd. (72) Inventor Shigeo Amagi 7-1-1, Omika-cho, Hitachi-shi, Ibaraki Inside Hitachi, Ltd.Hitachi Research Laboratories (72) Inventor Yasuomi Yagi 3-1-1, Sachimachi, Hitachi, Ibaraki Prefecture Inside Hitachi, Ltd.Hitachi Works (72) Inventor Tomoya Kakuda 3-chome, Sachimachi, Hitachi, Ibaraki No. 1-1 Inside the Hitachi Works, Hitachi, Ltd.

Claims (12)

[Claims] 1. A stator winding comprising a stator and a rotor rotatably provided on the inner peripheral side of the stator via a gap, wherein the stator has an outer side covered by main insulation. Wherein the main insulation is a first insulating layer in which a flaky conductive insulating material substantially free of a granular filler is bonded with a thermosetting resin, a fibrous insulating material and a granular insulating material. And a second insulating layer obtained by dispersing and curing a high thermal conductive filler in a resin, and having an initial dielectric breakdown voltage V of 20 kV / mm or more in the thickness direction of the main insulation. The thermal conductivity λ in the vertical direction is 0.35-1 W / m · K, and the product V · λ of the initial dielectric breakdown voltage and the thermal conductivity is 7 ≦ Vλ ≦ 20 (MVW
/ M ² · K). 2. The rotating electric machine according to claim 1, wherein said thermal conductivity λ is 0.5-1 W / m · K. 3. The insulating material according to claim 1, wherein said second insulating layer is a material obtained by dispersing and curing a granular insulating material having a thermal conductivity of 20 W / m · K or more together with a fiber cloth in a resin. The rotating electric machine according to item 1. 4. An insulating material formed by filling or mixing a thermosetting resin or a thermoplastic resin alone or in combination with a particulate or short-fiber insulating material having a thermal conductivity of 5 W / m · K or more. The rotating electric machine according to claim 1, wherein a spacer is interposed between end windings of the stator winding. 5. The rotating electric machine according to claim 1, wherein the thermal conductivity of the main insulation measured by a heat conduction sensor is 0.35 W / m · K or more. 6. A rotating electric machine wherein the inside of the machine is cooled by hydrogen, wherein the ratio of the product of the square of the diameter of the rotor and the axial length of the stator to the power generation capacity per number of rotations is 40 m ³ · r.
The rotating electric machine according to claim 1, wherein the rotation speed is not more than pm / MVA. 7. A rotating electric machine in which the inside of the machine is cooled by air, wherein a ratio of a product of a square of a diameter of the rotor and a shaft length of the stator to a power generation capacity per number of rotations is 70 m ³ · r.
The rotating electric machine according to claim 1, wherein the rotation speed is not more than pm / MVA. 8. A rotating electric machine in which the inside of the machine is cooled by hydrogen, wherein the ratio of the product of the square of the diameter of the rotor and the length between the supports of the rotating shaft to the power generation capacity per revolution is 5%.
2. The rotating electric machine according to claim 1, wherein the rotation speed is 0 m ³ · rpm / MVA or less. 9. A rotating electric machine in which the inside of the machine is cooled by air, wherein the ratio of the product of the square of the diameter of the rotor and the length between the supports of the rotating shaft to the power generation capacity per revolution is 8%.
2. The rotating electric machine according to claim 1, wherein the rotation speed is 5 m ³ · rpm / MVA or less. 10. A rotor provided on the inner peripheral side of the stator so as to be rotatable via a gap, the rotor comprising: a rotor winding housed in a plurality of slots formed in a rotor core. A slot insulation disposed between the rotor winding and the slot, and a wedge and the rotor winding disposed on an outer peripheral side of the rotor core with respect to the rotor winding of the slot. A rotation having an insulating block disposed therebetween, a retaining ring for fixing the rotor winding on both axial sides of the rotor core, and a retaining ring insulation disposed between the rotor windings; In the electric machine, at least one of the slot insulation, the insulation block, and the retaining ring insulation is formed by filling a resin with a particulate and / or short fiber insulator having a thermal conductivity of 5 W / m · K or more. Mix and form Is, the thickness direction of the thermal conductivity 0.3
A rotating electric machine characterized by being an insulating material of 5 W / m / K or more. 11. A rotor winding housed in a plurality of slots provided on the outer peripheral side of the iron core and having conductors and insulators alternately stacked in the radial direction of the iron core, and the rotor winding and the slot. A slot insulation interposed therebetween, a wedge for fixing the rotor winding in the slot, an insulation block interposed between the wedge and the rotor winding, and an axial end side of the iron core. In the rotor of a rotating electrical machine having a retaining ring for fixing the rotor winding and a retaining ring insulation interposed between the retaining ring and the rotor winding, the slot insulation or the insulation At least one of the block and the retaining ring insulation is formed by dispersing and curing a high thermal conductive particulate insulator having a thermal conductivity of 5 W / m · K or more and a fiber cloth in a resin, and The rotor of the rotary electric machine, wherein the thermal conductivity of an insulating material is 0.35 W / m · K or more. 12. At least one of said slot insulation, said insulation block and said retaining ring insulation is 5W
/ M · K is formed by dispersing and curing a particulate insulator and a fiber cloth having a thermal conductivity of at least 0.35 W / m / K in the thickness direction. The rotating electric machine according to claim 1, wherein: