JP2013143810A - Insulating paper and rotary electric machine using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide insulating paper capable of changing electrostatic capacity according to a kind of an electronic apparatus, and to provide an electronic apparatus and a rotary electric machine using the same.SOLUTION: The insulating paper includes, in a body part 20 formed paper-like with an insulating material, an air layer region that is formed by a recess 21 containing air whose dielectric constant is lower than that of the insulating material, and is equally arranged in a surface direction of the body part 20.

Description

  Embodiments described herein relate generally to insulating paper and a rotating electrical machine using the same.

  When insulating a conductor, insulating paper obtained by forming an insulating material into a paper shape is widely used. As such insulating paper, for example, paper that satisfies required insulating performance is adopted in consideration of heat resistance, oil resistance, mechanical strength, and the like.

  Now, when a high-frequency current flows through a conductor covered with insulating paper, noise may occur. For example, assuming a rotating electrical machine for a so-called electric vehicle or hybrid vehicle as an example of using insulating paper, the rotating electrical machine has a leakage current due to the switching speed and carrier frequency of an inverter that is a drive circuit, the stray capacitance and impedance of the rotating electrical machine, and the like. Occur. And the noise is radiated | emitted to the frequency band of the electronic device mounted in the vehicle, for example, AM radio, with the leakage current. In this case, it is possible to suppress the influence of noise by changing the frequency characteristics of the leakage current by changing the capacitance of the slot insulation paper or interphase insulation paper, but depending on the type of electronic equipment, the noise may be reduced. It is assumed that the frequency bands that affect are different.

JP 2011-72128 A

  The problem to be solved by the present invention is to provide an insulating paper whose capacitance can be changed according to the type of electronic device, an electronic device using the insulating paper, and a rotating electrical machine.

  In the insulating paper of the embodiment, an air layer region containing air having a dielectric constant lower than that of the insulating material is evenly arranged in the surface direction of the main body in the main body formed in a paper shape with an insulating material. It is characterized by being.

The figure which shows typically the rotary electric machine to which the slot insulation paper and phase insulation paper of 1st Embodiment are applied. The figure which shows the detail of II area | region of FIG. 1 of 1st Embodiment The figure which shows typically the side surface of the rotary electric machine of 1st Embodiment. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the slot insulation paper of 1st Embodiment typically, (A) is a top view of slot insulation paper, (B) is sectional drawing in the BB line of (A). The figure which shows typically the state which inserted the slot insulation paper of 1st Embodiment in the slot. The figure which shows the frequency characteristic of the impedance of the rotary electric machine of 1st Embodiment. The figure which shows typically the state which inserted the slot insulation paper of the modification of 1st Embodiment in the slot. The figure which shows typically the slot insulation paper of the modification of 1st Embodiment. FIG. 2 schematically shows a slot insulating paper according to a modification of the first embodiment. FIG. 3 schematically shows a slot insulating paper according to a modification of the first embodiment, where (A) is a slit shape, (B) is a lattice shape, and (C) is an oblique slit-shaped recess. FIG. 4 schematically shows a slot insulating paper according to a modification of the first embodiment. FIG. 6 is a diagram schematically showing a slot insulating paper according to a second embodiment, in which (A) is a slot insulating paper provided with a concave portion, (B) is a slot insulating paper provided with a concave portion and a convex portion, and (C) is a through hole. Diagram showing the provided slot insulation paper

Hereinafter, a plurality of embodiments of insulating paper and a rotating electrical machine using the same will be described with reference to the drawings. Note that, in a plurality of embodiments described below, substantially the same components are denoted by the same reference numerals, and detailed description thereof is omitted.
(First embodiment)
Hereinafter, the insulating paper according to the first embodiment and the rotating electrical machine using the same will be described with reference to FIGS. 1 to 6.
As shown in FIG. 1, the rotating electrical machine 1 includes a stator 2 and a rotor 3. The stator 2 and the rotor 3 are accommodated in a housing (not shown). In the case of this embodiment, the rotary electric machine 1 assumes an electric motor used for driving an electric vehicle or a hybrid vehicle.

The stator 2 is formed in a substantially cylindrical shape, for example, by laminating iron core pieces 4 obtained by pressing a silicon steel plate in an annular shape in the thickness direction. The stator 2 has a slot 5 provided along the stacking direction of the core pieces 4 and a coil 6 inserted into the slot 5. In FIG. 1, the coil 6 is schematically shown by hatching.
As shown in FIG. 2, the coil 6, the slot insulating paper 7, and the wedge 8 are inserted into the slot 5. The coil 6 is formed by winding a strand such as an enamel wire or a litz wire obtained by bundling a plurality of strands. The coil 6 is inserted into the slot 5 and then molded by the varnish 9 to prevent the strands from being separated. In this embodiment, the coils 6 are provided for three phases of U phase, V phase, and W phase, and three-phase AC power is supplied from a drive circuit (not shown). The occupation ratio of the coil 6 in the slot 5 is approximately 80% to 85% in the sectional view shown in FIG.

When the coil 6 is inserted into the slot 5, as shown in FIG. 3, the coil 6 protrudes from both sides in the stacking direction of the stator 2 to form a coil end 10. In FIG. 3, the U phase is shown as a coil 6u, the V phase as a coil 6v, and the W phase as a coil 6w. The coil end 10 is formed in the whole area in the circumferential direction on both ends in the stacking direction of the stator 2. The coil end 10 is provided with interphase insulating paper 11 between the coils 6 of each phase.
The slot insulating paper 7 corresponds to the insulating paper described in the claims, and is provided between the coil 6 and the inner wall of the slot 5. The slot insulating paper 7 insulates between the coil 6 and the slot 5. As shown in FIGS. 2 and 3, the slot insulating paper 7 is formed slightly longer than the entire length (length in the stacking direction) of the stator 2 along the inner wall of the slot 5. For this reason, the slot insulating paper 7 covers the inner wall of the slot 5 with a certain thickness maintained over the entire length of the stator 2 in the stacking direction.

The interphase insulating paper 11 corresponds to the insulating paper described in the claims, and insulates the coils 6 of each phase at the coil end 10. The slot insulating paper 7 and the interphase insulating paper 11 are formed of aramid paper, which is an insulating material in this embodiment. Details of the shapes of the slot insulating paper 7 and the interphase insulating paper 11 will be described later.
As shown in FIG. 2, the wedge 8 blocks the opening of the slot 5 to prevent the coil 6 from jumping out of the slot 5 and contacting the rotor 3. The wedge 8 may be formed of the same as the slot insulating paper 7 or may be formed of so-called engineering plastic.

  As shown in FIG. 1, the rotor 3 is provided coaxially with the stator 2 on the inner peripheral side of the stator 2. The rotor 3 is formed in a generally cylindrical shape by laminating core pieces 12 obtained by pressing a silicon steel plate into a disk shape, for example. The rotor 3 is provided with a shaft hole 13 at the center thereof. A rotating shaft 14 is fixed to the shaft hole 13 by, for example, press fitting. Further, the rotor 3 is formed with a plurality of conductor holes 15 penetrating the rotor 3 in the stacking direction in the entire circumferential direction. The conductor hole 15 is filled or inserted with a conductor 16 such as aluminum or copper. The conductors 16 are electrically connected (short-circuited) to each other by end rings (not shown) at both ends of the stator 2 in the stacking direction. A current induced by the coil 6 of the stator 2 flows through the conductor 16. That is, the rotating electrical machine 1 is a so-called cage type three-phase induction motor.

Here, details of the slot insulating paper 7 and the interphase insulating paper 11 will be described.
As shown in FIG. 4 (A), the slot insulating paper 7 includes a main body 20 formed of aramid paper in a rectangular and paper shape, and one surface of the main body 20 as shown in FIG. And a plurality of recesses 21 formed on the surface for convenience). FIG. 4B is a cross-sectional view taken along line BB in FIG. 4 and FIGS. 5 and 7 to 12 described later schematically show the slot insulating paper 7 and the concave portion 21 and the like, and show the sizes of the actual slot insulating paper 7 and the concave portion 21 and the like. It is not a thing.

The concave portion 21 is formed to be recessed from the surface of the main body portion 20 to the inside in the thickness direction. The recess 21 is formed as a substantially spherical recess. The main body 20 has a width W, a depth D, and a height (thickness) H. As shown in FIGS. 4A and 4B, the recess 21 is provided in the entire region on the surface side of the main body 20 of the slot insulating paper 7. In other words, the recesses 21 are evenly arranged in the surface direction of the main body 20. Here, the uniform arrangement includes not only the state where the dimensions between the recesses 21 are formed to be the same, but also the state where the dimensions between the recesses 21 are formed differently. That is, the uniform arrangement in the present embodiment means a state in which the concave portion 21 is formed without deviation when viewed in the surface direction of the main body portion 20.
In addition, although illustration is abbreviate | omitted, in this embodiment, the recessed part 21 is similarly provided in the surface direction similarly to the interphase insulating paper 11, too.

  As shown in FIG. 5, the slot insulating paper 7 is accommodated in the slot 5 with its surface in contact with the inner wall of the slot 5. Therefore, a space is formed between the slot insulating paper 7 and the inner wall of the slot 5 in the recess 21, and air exists in the space. Here, the dielectric constant of the aramid paper forming the main body 20 is approximately 2.5, and the dielectric constant of air is approximately 1.0. That is, by providing the recess 21, an air layer region R including air having a dielectric constant lower than that of the aramid paper is present in the entire space in the plane direction of the slot insulating paper 7 in the occupied space occupied by the slot insulating paper 7. It is formed substantially evenly in the plane direction. Here, the occupied space of the slot insulating paper 7 is a space including the outermost edge portion of the slot insulating paper 7, and in the present embodiment, the occupied space is in a range of width W × depth D × height H. . Note that, as shown in FIG. 3, a part of the slot insulating paper 7 protrudes from the stator 2 and is not strictly in the range of width W × depth D × height H. The occupied space is a range of width W × depth D × height H.

Next, the operation of the slot insulating paper 7 and the interphase insulating paper 11 and the rotating electrical machine 1 having the above-described configuration will be described.
When the rotating electrical machine 1 is used in a vehicle, the high-frequency current flowing through the coil 6 of the rotating electrical machine 1 flows to the stator 2 as a leakage current due to the impedance corresponding to the electrostatic capacity of the slot insulating paper 7 and passes through the casing. Leak into the car body. Such a leakage current is radiated as noise to various electronic devices mounted on the vehicle according to the frequency and the magnitude of the current. At this time, the magnitude of the radiated noise correlates with the magnitude of the leakage current. And how much leakage current is generated in which frequency band depends on the impedance of the slot insulating paper 7. In other words, the frequency characteristic of the leakage current changes depending on the capacitance of the slot insulating paper 7.

  Here, an insulating paper having a conventional configuration, specifically, an insulating paper using an aramid paper in which the concave portion 21 (that is, the air layer region R) is not formed will be considered. The insulating paper having a conventional configuration has the same shape as the slot insulating paper 7 (width W, depth D, height (thickness) H). In the case of this conventional insulating paper, as shown by a solid line (comparative example) in FIG. 6, the impedance of the insulating paper is high in the frequency band of several hundred kHz to several hundreds of kHz. That is, in the case of the insulating paper having the conventional configuration, the leakage current of several hundred kHz to several hundreds of kHz is increased, and the noise radiated in the frequency band is increased. And noise of several hundred kHz to several hundreds of kHz may affect an AM radio as an example of an electronic device for a vehicle. That is, since the frequency band of the AM radio is about 500 kHz to 1500 kHz, the generated noise becomes large when the impedance of the slot insulating paper 7 in the band is high, and noise is mixed into the AM radio, causing problems such as poor reception. The fear increases.

In this case, by reducing the impedance of the slot insulating paper 7 in the frequency band of the AM radio, more strictly, by shifting the impedance peak of the slot insulating paper 7 from the frequency band of the AM radio, the adverse effect on the AM radio is reduced. Can be reduced.
In order to shift the impedance peak of the slot insulating paper 7 from the frequency band of the AM radio, the capacitance of the slot insulating paper 7 may be changed. The capacitance C of the slot insulating paper 7 is
Capacitance C = ρ × (A ÷ d)
Where ρ = dielectric constant, A = surface area of the slot insulating paper 7, and d = thickness of the slot insulating paper 7.

  Here, the surface area A of the slot insulating paper 7 corresponds to the area of the inner wall of the slot 5. Therefore, in order to change the surface area A, it is necessary to change the shape of the slot 5, that is, the shape of the rotating electrical machine 1. However, it is substantially difficult to change the design of the rotating electrical machine 1 because it is necessary to change the characteristics of the rotating electrical machine 1 or to change the arrangement location on the vehicle side. Further, if the thickness of the slot insulating paper 7 (height H in FIG. 4B) is changed, the area occupied by the slot insulating paper 7 in the slot 5 increases, and the coil 6 that can be inserted into the slot 5 becomes larger. The amount decreases. That is, when the slot insulating paper 7 is thickened, the amount of the coil 6 is reduced, which causes a reduction in performance of the rotating electrical machine 1 such as a reduction in output. For this reason, in order to reduce the influence of noise without changing the shape of the rotating electrical machine 1 and without degrading the characteristics of the rotating electrical machine 1, the electrostatic capacity of the slot insulating paper 7, that is, the electrostatic capacity is reduced. It is necessary to change the proportional dielectric constant.

  The inventors have obtained the target dielectric constant for shifting the impedance peak of the slot insulating paper 7 from the frequency band of the AM radio by repeating simulation and experiment. More specifically, in order to shift the impedance peak of the slot insulating paper 7 to the position shown by the broken line (example) in FIG. 6, the dielectric constant of the slot insulating paper 7 should be about 2.1. I know that. As is well known, the relationship between the impedance peak deviation amount and the dielectric constant is calculated from the relationship between the resonance frequencies.

  In this case, since the dielectric constant of the aramid paper is about 2.5 as described above, in order to lower the dielectric constant of the slot insulating paper 7, it is first considered to review the insulating material itself. However, the dielectric constant of polyethylene naphthalate or polyethylene terephthalate, which is generally used as insulating paper, is about 3.5, which is higher than that of aramid paper. In addition, polytetrafluoroethylene, which has a low dielectric constant of approximately 2.0 and good environmental resistance, is very expensive compared to aramid paper and the like, and if used as insulating paper, it will cause a significant increase in cost. .

Therefore, in this embodiment, the dielectric constant of the slot insulating paper 7 is lowered by providing the air layer region R described above.
The dielectric constant ρ1 of the slot insulating paper 7 provided with the air layer cool air R is such that the air layer region R in the occupied space of the slot insulating paper 7 is formed at a volume ratio of X%. From approximately 2.5), the dielectric constant of air (approximately 1.0), the depth of the recess 21 and the like, it can be approximately approximated by the equation ρ1 = 2.5 × (1−X) + 1.0 × X. Since the target dielectric constant ρ1 is 2.1 this time, 2.1 = 2.5 × (1−X) + 1.0 × X, that is, X = 26.7%. That is, if the air layer region R is formed in the occupied space of the slot insulating paper 7 at a rate of approximately 26.7%, the impedance peak is shifted to the position indicated by the broken line in FIG.

  As described above, in the case of the slot insulating paper 7 formed of aramid paper, the air layer region R is formed at a ratio of approximately 26.7% in the occupied space, so that the slot insulating paper 7 as a whole is formed. Is changed, and the frequency characteristics of the leakage current are changed. Thereby, the impedance peak is shifted from the frequency band of the AM radio, and the influence on the AM radio is reduced. Further, since the air layer region R is also formed in the interphase insulating paper 11 at a ratio of approximately 26.7% in the occupied space, the influence on the AM radio is further reduced. When it is desired to reduce noise for an electronic device other than the AM radio, the air layer region R is formed so as to shift the impedance peak position to a position corresponding to the electronic device, that is, to have a desired dielectric constant. Of course, the ratio to be changed may be changed.

According to the slot insulating paper 7, the interphase insulating paper 11, and the rotating electrical machine 1 according to the embodiment described above, the following effects can be obtained.
The slot insulating paper 7 and the interphase insulating paper 11 are formed with a concave portion 21 in which air having a dielectric constant lower than that of the aramid paper can be present in the main body portion 20 formed of an aramid paper that is an insulating material. The air layer region R is formed uniformly in the surface direction of the main body 20. As a result, the dielectric constant when viewed from the whole slot insulating paper 7 changes according to the proportion of the air layer region R in the occupied space. Accordingly, the capacitance of the slot insulating paper 7 can be changed according to the type of electronic device. As a result, the magnitude of the leakage current with respect to a desired frequency band, that is, the frequency characteristics of the leakage current can be changed, and the influence of noise due to the leakage current can be reduced.

As the slot insulating paper 7 and the interphase insulating paper 11, the same aramid paper as in the conventional configuration is used. Therefore, since a desired dielectric constant can be achieved without using expensive polytetrafluoroethylene, the manufacturing cost is not significantly increased.
Further, since the air layer region R is formed by the plurality of recesses 21 that are recessed in the thickness direction of the main body 20, the occupied space occupied by the slot insulating paper 7 in the slot 5 does not increase. Accordingly, since the amount of the coil 6 that can be accommodated in the slot 5 does not change, the characteristics of the rotating electrical machine 1 are not deteriorated, for example, the output is reduced.

In addition, since the air layer region R is evenly arranged in the surface direction of the main body 20, the frequency characteristics of the leakage current can be changed in the entire rotating electrical machine 1.
In this case, the air layer region R is provided in order to change the dielectric constant and thus the capacitance. Therefore, if the air layer region R is too small, the amount of change in the dielectric constant is reduced, and a desired dielectric constant is obtained. I can't do that. On the other hand, if there are too many air layer regions R, for example, the air layer region R is crushed by the coil 6, the volume ratio with respect to the occupied space decreases, and there is a possibility that a desired dielectric constant cannot be obtained. Therefore, it is possible to change the dielectric constant to some extent, and the air layer region R is approximately in a volume ratio with respect to the occupied space as a range having a strength not to be crushed by a member that the air layer region R contacts. It is good to form in 20 to 80% of range.

In this case, assuming an AM radio for a vehicle as an electronic device affected by noise, when the slot insulating paper 7 and the interphase insulating paper 11 are formed of aramid paper, the air layer region is approximately 26.7%. If R is formed, the impedance peak can be shifted from the frequency band of the AM radio.
Further, the slot insulating paper 7 may be inserted into the slot 5 after the coil 6 is inserted in the manufacturing process of the rotating electrical machine 1. In that case, the slot insulating paper 7 is required to have a certain strength. Even in such a manufacturing process, the strength of the slot insulating paper 7 is not excessively lowered because it is provided uniformly over the entire area of the main body 20.

  According to the rotating electrical machine 1 to which the above-described slot insulating paper 7 and interphase insulating paper 11 are applied, noise in the frequency band of AM radio can be reduced. And by using the rotary electric machine 1 for a vehicle, it is possible to reduce the possibility that noise will be mixed into the AM radio, and to reduce the possibility that the user will suffer a disadvantage.

(Modification of the first embodiment)
Hereinafter, insulating paper according to a modification of the first embodiment will be described with reference to FIGS. The insulating paper of the modified example of the first embodiment is different from the first embodiment in the configuration of the air layer region R.
In the first embodiment, the air layer region R is formed by the recess 21, but the air layer region R may be formed by other than the recess 21.
For example, as shown in FIG. 7, the slot insulating paper 7 may be provided with a plurality of convex portions 30 protruding outward from the main body portion 20 in the thickness direction, and the air layer region R may be formed between the convex portions 30. . In this case, as in the first embodiment, the air layer region R is formed in the occupied space of the slot insulating paper 7 (range E indicated by a broken line in FIG. 7) at a ratio that provides a target dielectric constant. Good. In FIG. 7, the convex portion 30 is disposed on the inner wall side of the slot 5, but the convex portion 30 may be disposed on the coil 6 side.

  Even with such a configuration, similarly to the first embodiment, it is possible to reduce the influence of noise by shifting the impedance peak without causing a significant increase in cost or a change in shape. In this case, the air layer region R can be increased as compared with the configuration in which only the recess 21 is provided. For example, when polyethylene naphthalate or polyethylene terephthalate (dielectric constant is approximately 3.5) is used as the insulating paper of the rotating electrical machine 1, when the dielectric constant is to be set to 2.1, for example, the relative dielectric constant is higher than that of aramid paper. In addition, many air layer regions R are required. Specifically, 2.1 = 3.5 × (1−X) + 1.0 × X, that is, X = 56%. Further, when the dielectric constant is increased by adding a filler to the insulating material, the ratio of the air layer region R is further increased.

  When the required air layer region R is large in this way, the main body portion 20 is provided with the convex portions 30 and the air layer regions R are formed between the respective convex portions 30 to thereby form the air layer region R in the occupied space. The ratio can be easily expanded. In other words, by forming the air layer region R between the protrusions 30, the adjustment range of the dielectric constant can be easily expanded. In addition, the convex part 30 has the substantially same meaning as the case where the wide recessed part 21 is provided in 1st Embodiment and the part between the recessed parts 21 is considered as the convex part 30. FIG.

Further, as shown in FIG. 8, the main body portion 20 may be provided with a concave portion 21 and a convex portion 30. In this case, by providing the concave portions 21 on the front surface side of the slot insulating paper 7 by embossing, the convex portions 30 can be formed on the corresponding back surface side, and the concave portions 21 and the convex portions 30 can be efficiently provided. Moreover, since the air layer area | region R formed of the recessed part 21 and the air layer area | region R formed of the convex part 30 exist, the ratio of the air layer area | region R can be changed more finely and more widely.
Further, as shown in FIG. 9, an air layer region R may be provided inside the slot insulating paper 7. In this case, the air layer region R can be formed inside the slot insulating paper 7 by bonding the insulating paper pieces 31 and 32 provided with the recesses 21 together. In this case, for example, since the wire of the coil 6 does not enter the air layer region R, the possibility that the volume ratio of the air layer region R changes can be reduced. The concave portions 21 of the insulating paper pieces 31 and 32 do not necessarily have to coincide with each other.

Moreover, the shape of the recessed part 21 and the convex part 30 is not restricted to spherical shape as mentioned above, A rectangular shape may be sufficient. Specifically, the concave portion 21 and the convex portion 30 may have a slit shape as shown in FIGS. 10A and 10B or a lattice shape as shown in FIG. Of course, only the concave portion 21 or only the convex portion 30 may be formed in a slit shape or a lattice shape.
In addition, as shown in FIG. 11, a through hole 33 that penetrates the main body 20 of the slot insulating paper 7 in the thickness direction may be provided, and the air layer region R may be formed by the through hole 33. In this case, the through hole 33 may be formed in an arbitrary shape such as a circular shape, a rectangular shape, or a slit shape (through groove).

As described above, the air layer region R can be formed by the concave portion 21, the convex portion 30, the through hole 33, and the like. In this case, an arbitrary shape may be formed according to the type of insulating material, required strength, and the like. In any case, if the air layer region R is formed at a desired ratio in the occupied space of the slot insulating paper 7 or the interphase insulating paper 11, the slot insulating paper 7 is appropriately used according to the type of electronic device affected by noise. It can be made to become a dielectric constant.
The rotating electrical machine 1 using the slot insulating paper 7 or the interphase insulating paper 11 having such a configuration can reduce noise in a band that affects, for example, an AM radio, as in the first embodiment.

(Second Embodiment)
Hereinafter, the insulating paper according to the second embodiment will be described with reference to FIG. The insulating paper of the second embodiment is different from the first embodiment in that it includes a film member that covers the air layer region.
As shown in FIGS. 12A to 12C, the slot insulating paper 7 according to the second embodiment includes a main body portion 20 provided with a concave portion 21, a convex portion 30 or a through-hole 33, a concave portion 21, and a convex portion. 30 or a film member 40 that covers the air layer region R formed by the through hole 33. In the present embodiment, aramid paper is used for the film member 40. The main body 20 is formed of aramid paper in the present embodiment as in the first embodiment, but may be formed of another insulating material because it is covered with the film member 40.

  When insulating between the object A (for example, the slot 5) and the object B (for example, the coil 6), the dielectric constant varies depending on the thickness of the insulator existing between the objects A and B as described above. To do. Therefore, for example, in the rotating electrical machine 1, in the manufacturing process, after the coil 6 is inserted into the slot 5, the coil end 10 is molded and then fixed by impregnation with the varnish 9. The varnish 9 may enter the region R (in the concave portion 21, between the convex portions 30, and in the through hole 33), and the ratio of the air layer region R in the occupied space may be reduced. Further, the strands of the coil 6 may enter the air layer region R. Furthermore, during operation of the rotating electrical machine 1, for example, cooling oil or the like may enter the air layer region R.

  Therefore, by providing the film member 40 that covers the air layer region R, the varnish 9, strands, cooling oil, or the like is prevented from entering the air layer region R. Thereby, the air layer region R formed to have a desired dielectric constant can be maintained in a state in which the ratio is maintained. Therefore, it is possible to prevent the dielectric constant of the slot insulating paper 7 from being changed during manufacturing or due to changes over time, and a desired noise reduction effect can be continuously obtained.

(Other embodiments)
It is good also as a structure which provides the recessed part 21 and the through-hole 33 in the main-body part 20, or provides the convex part 30 and the through-hole 33 in the main-body part 20. FIG. Moreover, it is good also as a structure which provides all the recessed part 21, the convex part 30, and the through-hole 33. FIG. Furthermore, it is good also as a structure which provides the film member 40 with respect to them. In other words, the configuration for forming the air layer region R may be an arbitrary combination.
Although an induction motor is shown as an example of the rotating electrical machine 1, it may be a permanent magnet type rotating electrical machine or a generator.
In each embodiment, an example in which insulating paper is applied to the slot insulating paper 7 and the interphase insulating paper 11 of the rotating electrical machine 1 has been described. However, the application range of the insulating paper is not limited to the rotating electrical machine 1. Alternatively, the insulating paper may be applied only to the slot insulating paper 7.

The type of insulating material and the desired dielectric constant shown in each embodiment are examples, and may be changed as appropriate according to the specifications of the apparatus using insulating paper.
As described above, according to the insulating paper of the embodiment and the rotating electrical machine using the insulating paper, the body portion formed in a paper shape with the insulating material contains air having a lower dielectric constant than the insulating material. Since the air layer region is evenly arranged in the surface direction of the main body, the dielectric constant of the insulating paper can be changed to a desired value, and the capacitance of the insulating paper can be changed according to the type of electronic device. Can be changed to an appropriate value.

Further, by applying such insulating paper as slot insulating paper or interphase insulating paper to a rotating electrical machine, it is possible to reduce the influence of generated noise.
Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  In the drawings, 1 is a rotating electrical machine, 2 is a stator, 5 is a slot, 6 is a coil, 7 is slot insulating paper (insulating paper), 11 is interphase insulating paper (insulating paper), 20 is a main body, 21 is a recess, Reference numeral 30 denotes a convex portion, 33 denotes a through hole, and 40 denotes a film member.

Claims (6)

Insulating paper formed of an insulating material,
An insulating paper, characterized in that an air layer region containing air having a dielectric constant lower than that of the insulating material is uniformly arranged in the surface direction of the main body portion on the main body portion formed of the insulating material.   The air layer region includes a plurality of recesses recessed inward in the thickness direction of the main body, a plurality of protrusions protruding outward in the thickness direction of the main body, and a through-hole penetrating the main body in the thickness direction. The insulating paper according to claim 1, wherein the insulating paper is formed of any one of the above or a combination thereof.   The insulating paper according to claim 1, further comprising a film member provided on at least one surface of the main body portion and covering the air layer region.   The insulating paper according to any one of claims 1 to 3, wherein the insulating material is aramid paper mainly composed of aramid fibers. Rotating electricity comprising a stator and a coil inserted into a slot of the stator,
5. A rotating electrical machine, wherein the insulating paper according to claim 1 is used as slot insulating paper for insulating the slot and the coil in the slot. Rotating electricity comprising a stator and a coil inserted into a slot of the stator,
The insulating paper according to any one of claims 1 to 4 is used as an interphase insulating paper that insulates the coils of a plurality of phases at coil ends formed at both ends of the stator in the axial direction. Rotating electric machine.

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