JP2011234429A - Phase-to-phase insulating paper of rotary electric machine, and rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phase-to-phase insulating paper of a rotary electric machine which can prevent a coil end from being torn or shifted in coil end molding compression, and a rotary electric machine.SOLUTION: A phase-to-phase insulating paper of a rotary electric machine of this embodiment comprises: a pair of phase-to-phase insulating paper main body formed in a shape which can insulate the coil ends of a stator coil of multiple phases in both the edges of the axial direction of a stator core; a coupling streak portion provided to lead the pair of phase-to-phase insulating paper main body and positioned in a slot. The phase-to-phase insulating paper main body is composed of multiple layers, and of these multiple layers, a friction coefficient between the external layer positioned on the outer peripheral side of the stator core and the magnet wire of the coil end is bigger than a friction coefficient between the internal layer positioned on the inner peripheral side of the stator core and the magnet wire of the coil end.

Description

  The present embodiment relates to an interphase insulating paper for a rotating electrical machine and the rotating electrical machine.

  In a rotating electrical machine, interphase insulating paper is provided between the coil ends of the stator coil to insulate the coil end phases. As this interphase insulating paper, considering heat resistance, oil resistance, mechanical strength, etc., for example, aramid paper alone made of aramid polymer, or both sides of this aramid paper are made of polyethylene naphthalate film with excellent electrical insulation. A sheet material having a three-layer structure sandwiched between them is often used.

By the way, in recent years, electric vehicles (including hybrid vehicles) have attracted attention due to problems of the global environment, and downsizing of an on-vehicle rotating electrical machine as a driving source is desired.
For this reason, conventionally, the coil end of the stator coil that protrudes largely outward from both ends of the stator core is expanded in the outer circumferential direction of the stator core and compressed in the axial direction to protrude the coil end. Reducing the dimensions has been done. However, the interphase insulating paper made of the above-described sheet material has a problem that the deformation amount of the coil end at the time of coil end molding compression cannot be absorbed and the interphase insulating paper is torn or displaced.

JP 2006-288041 A

  In view of this, an interphase insulating paper for a rotating electrical machine and a rotating electrical machine that can prevent breakage and displacement with respect to the movement of the coil end during coil end molding compression of the stator coil are provided.

  The interphase insulating paper of the rotating electrical machine of the present embodiment includes a pair of interphase insulating paper main bodies formed in a shape capable of insulating between the coil ends of the stator coils of a plurality of phases at both axial end portions of the stator core, and the pair The interphase insulating paper body is connected to the stator core and is located in the slot of the stator core, and the interphase insulating paper body includes a plurality of layers, and the fixing of the plurality of layers The friction coefficient between the outer layer located on the outer peripheral side of the core and the magnet wire of the coil end is larger than the friction coefficient between the inner layer located on the inner side of the stator core and the magnet wire of the coil end. It is characterized by that.

The perspective view of the stator of the state by which the three-phase stator coil and phase insulation paper which show 1st Embodiment are arrange | positioned (A) is a cross-sectional view of the stator before forming the coil end, (b) is a cross-sectional view of the stator after forming the coil end. (A) is a perspective view of the interphase insulating paper in a state where the bent portion is not extended, (b) is a perspective view of the interphase insulating paper in a state where the bent portion is extended. Development view of the stator with the coil ends tied with thread Sectional view along line AA in FIG. FIG. 5 equivalent view showing the second embodiment FIG. 5 equivalent diagram showing the third embodiment FIG. 5 equivalent view showing the fourth embodiment

(First embodiment)
Hereinafter, a first embodiment applied to an in-vehicle rotating electrical machine will be described with reference to FIGS. 1 to 5.
As shown in FIG. 1, the stator 1 has a cylindrical stator core 3 having a plurality of slots 2. A plurality of phases (in this embodiment, three phases U, V, W) of stator coils 5 are inserted into the slots 2 through slot insulating paper 4 (see FIG. 2), and both ends of the coils are coiled. The end 6 protrudes from the stator core 3. In addition, as shown in FIG. 2, a plurality of stator coils 5 are arranged between the coil ends 6 (U) and 6 (V) and between 6 (V) and 6 (W). For example, a total of eight interphase insulating papers 7 are provided for each four sheets.

  As shown in FIG. 3, the interphase insulating paper 7 includes a pair of interphase insulating paper bodies 8 formed in a substantially rectangular shape so as to be able to insulate between the coil ends 6 of a plurality of phases, and the pair of interphase insulating papers 8. It comprises three connecting strips 9 formed integrally with the insulating paper body 8 so as to connect them. In the pair of interphase insulating paper bodies 8, two trapezoidal notches 10 are formed on the side where the interphase insulating paper bodies 8 face each other. Further, the pair of interphase insulating paper main bodies 8 are formed with two bent portions 11 each having two steps in the longitudinal direction of the interphase insulating paper main body 8. That is, the pair of interphase insulating paper bodies 8 have a symmetrical shape. Accordingly, the interphase insulating paper main body 8 can be expanded and contracted in the longitudinal direction as shown in FIGS. 3A and 3B (a state where FIG. 3B is extended).

  5, the interphase insulating paper main body 8 is positioned on one surface of the intermediate layer 8a (on the outer peripheral side of the stator core 3), as shown in the cross section of the interphase insulating paper main body 8 along the line AA in FIG. The outer layer 8b is affixed to the surface on which the inner layer 8c is adhered, and the inner layer 8c is affixed to the other surface (the surface located on the inner peripheral side of the stator core 3). For the intermediate layer 8a, for example, heat-resistant insulating paper excellent in electrical insulation performance, which is aramid paper subjected to calendering at high temperature and high pressure to be densified, is used. For the outer layer 8b, for example, a heat-resistant insulating paper having high flexibility, which is not subjected to the above-mentioned calendar processing on aramid paper, is used. In this case, compared with the heat-resistant insulating paper used for the intermediate layer 8a subjected to the calendering process, the outer layer 8b not subjected to the calendering process has a frictional force with the magnet wire (for example, enameled wire) of the coil end 6. Is big.

  Further, for the inner layer 8c, for example, heat-resistant insulating paper made of a fluororesin (for example, tetrafluoroethylene resin) excellent in low friction performance is used. In this case, the inner layer 8c made of fluororesin has a smaller frictional force with the magnet wire of the coil end 6 than the heat-resistant insulating paper used for the calendered intermediate layer 8a. As a result, the friction coefficient between the outer layer 8 b and the magnet wire of the coil end 6 is larger than the friction coefficient between the inner layer 8 c and the magnet wire of the coil end 6.

  Here, in this embodiment, a pair of interphase insulating paper main bodies 8 and a connecting strip 9 connecting them are integrally formed by punching one heat-resistant insulating paper having the three-layer structure. . For this reason, the connecting strip 9 also has a three-layer structure similar to the interphase insulating paper body 8. Incidentally, the pair of interphase insulating paper main bodies 8 may be configured to be connected by a connecting strip formed separately from the interphase insulating paper main body 8 (and a separate member). In this case, it is sufficient that the connecting strip has a heat-resistant insulating property.

  As shown in FIG. 2A, the interphase insulating paper 7 having such a structure is formed between the U and V phase coil ends 6 (U) and 6 (V) in which the interphase insulating paper main body 8 is a plurality of phases. The other interphase insulating paper 7 is arranged so that the interphase insulating paper main body 8 is positioned between the V and W phase coil ends 6 (V) and 6 (W). . In this case, the three connecting strips 9 of the interphase insulating paper 7 are positioned in appropriate slots 2 of the stator core 3. In FIG. 4, for convenience of explanation, the slot in which the connecting strip 9 is located is denoted by reference numeral 2 a.

  In addition, in the slot 2 of the stator core 3, first, of the three-phase stator coils 5 (U), 5 (V), and 5 (W), the W-phase stator coil 5 that is positioned on the outer peripheral side. (W) is inserted first. Next, the connecting strip 9 of the interphase insulating paper 7 disposed between the coil ends 6 (W) and 6 (V) is inserted and disposed. At this time, the calendar layer is not applied, that is, the outer layer 8b having a large friction coefficient with the magnet wire is arranged in a direction in contact with the W-phase coil end 6 (W), and the friction coefficient with the magnet wire is small. The inner layer 8c is disposed in a direction in contact with the V-phase coil end 6 (V).

  Next, the V-phase stator coil 5 (V) is inserted into the other slot 2. And the connecting strip 9 of the interphase insulating paper 7 disposed between the coil ends 6 (V) and 6 (U) is inserted and disposed. At this time as well, the outer layer 8b, which is not calendered and has a large friction coefficient with the magnet wire, is arranged in a direction in contact with the V-phase coil end 6 (V) and has a small friction coefficient with the magnet wire. The inner layer 8c is arranged in a direction in contact with the U-phase coil end 6 (U). Further, a U-phase stator coil 5 (U) located on the inner layer side is inserted into another slot 2. Thereby, the phase coil ends are insulated from each other by the interphase insulating paper 7.

  Thereafter, the coil end 6 is shaped so as to expand in the outer peripheral direction (upward in FIG. 2) of the stator core 3 as shown in FIG. And compressed in the central direction (left and right central direction in FIG. 2). At this time, as shown in FIG. 4 (in FIG. 4, the bent portion 11 is in an extended state), the interphase insulating paper main body 8 portion is thread 12 together with the coil end 6 (in FIG. Only the U-phase coil end 6 (U) is shown to be bound with the thread 12. In this state, varnish is dripped onto the coil end 6 and the stator coil 5 is impregnated with the varnish to harden the whole to constitute the stator 1.

  Here, as described above, a force (tensile force) is applied to the coil end 6 in the longitudinal direction or the width direction when the stator 1 is molded for the purpose of downsizing. As a result, the same force as that of the coil end 6 acts on the interphase insulating paper 7. In addition, since the amount of deformation of the coil end 6 when the stator coil 5 is arranged, that is, the coil end 6 (U), 6 (V), 6 (W) in each phase is different depending on the amount of deformation, The front and back surfaces of the interphase insulating paper main body 8 are pulled by forces of different directions and sizes, and the interphase insulating paper 7 may be wrinkled or torn.

  However, the present embodiment is configured to solve the above problem. Here, with reference to FIG. 2, the effect of this embodiment is demonstrated on behalf of the coil ends 6 (U) and 6 (V) among the three-phase coil ends 6. As described above, in the interphase insulating paper main body 8, the friction coefficient between the outer layer 8b and the magnet wire of the coil end 6 (V) is larger than the friction coefficient between the inner layer 8c and the magnet wire of the coil end 6 (U). . For this reason, when the coil end 6 is formed so as to expand in the outer peripheral direction of the stator core 3 and is compressed in the center direction, the outer layer 8b and the coil end 6 (V) have a large frictional force. Therefore, it moves (and deforms) without shifting. That is, the outer layer 8b moves following the movement of the coil end 6 (V).

  On the other hand, since the inner layer 8c and the coil end 6 (U) have a small frictional force, they move while sliding against each other. That is, the inner layer 8c moves without following the movement of the coil end 6 (U). As a result, only the frictional force between the outer layer 8b and the coil end 6 (V) is mainly transmitted to the front and back surfaces of the interphase insulating paper main body 8, so that the interphase insulating paper main body 8 has a small amount of deformation on the outer peripheral side coil. It moves following the end 6 (V) and does not follow the coil end 6 (U) on the inner peripheral side having a large deformation amount. Therefore, the front and back surfaces of the interphase insulating paper 7 are not pulled in different directions, and it is possible to prevent the interphase insulating paper main body 8 from being wrinkled or displaced and torn as much as possible. As a result, it is possible to effectively prevent wrinkles, tears, and displacement with respect to the movement of the coil end 6 when the coil end 6 is molded and compressed.

Further, the interphase insulating paper 7 of the present embodiment has a two-stage bent portion 11 formed in the interphase insulating paper main body 8 (see FIG. 3). For this reason, when the coil end 6 is formed, a longitudinal force (force in the circumferential direction of the stator core 3) is applied to the interphase insulating paper main body 8, that is, a force that breaks the interphase insulating paper main body 8 is applied. However, since this force is absorbed when the bent part 11 extends as shown in FIG. 3B, it is possible to prevent the interphase insulating paper body 8 from being broken as much as possible.
Further, a notch 10 is formed in the interphase insulating paper body 8. For this reason, even if the varnish is dropped with the interphase insulating paper main body 8 disposed on the coil end 6, the varnish easily flows through the notch 10, and the varnish permeability to the coil end 6 and the stator coil 5 is improved. It becomes possible to improve.
Since three connecting strips 9 are provided between the pair of interphase insulating paper main bodies 8, the connecting strip 9 is passed through the slot 2 of the stator core 3, so that the coil end The interphase insulating paper 7 can be accurately positioned with respect to 6.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIG.
In the second embodiment, the interphase insulating paper main body 13 has a two-layer structure as a plurality of layers obtained by directly bonding an outer layer 13b (corresponding to the outer layer 8b) and an inner layer 13c (corresponding to the inner layer 8c). According to the second embodiment, the same effect of preventing tears and wrinkles as in the first embodiment can be obtained with the two-layer structure interphase insulating paper. Here, since the second embodiment does not have the intermediate layer, the heat-resistant insulation performance is slightly inferior to that of the first embodiment, but it is advantageous in terms of flexibility and cost. Therefore, the first and second embodiments can be appropriately selected according to the specifications of the stator coil 5 (for example, the energization amount and the heat generation amount), and the choice of interphase insulating paper is expanded.

(Third embodiment)
FIG. 7 shows a third embodiment, which differs from the first embodiment in the following points.
The interphase insulating paper main body 14 of the third embodiment has an intermediate layer 14a made of aramid paper that has been subjected to calendering treatment in the same manner as the intermediate layer 8a. One surface of the intermediate layer 14a (the surface located on the outer peripheral side of the stator core 3) is subjected to surface treatment (increased friction treatment) such as electric discharge machining so that the friction coefficient with the magnet wire of the coil end 6 is increased. An increased outer layer 14b is formed. Further, the other surface of the intermediate layer 14a (the surface located on the inner peripheral side of the stator core 3) is subjected to processing (friction reduction processing) such as anti-friction agent application or fluid paraffin application, so that the coil end 6 is An inner layer 14c having a reduced coefficient of friction with the magnet wire is formed. In this way, by applying a process to increase or decrease the friction on the front and back surfaces of the intermediate layer 14a, the coefficient of friction with the magnet wire of the coil end 6 contacting the outer layer 14b and the inner layer 14c is larger on the outer layer 14b side, and the inner layer 14c side is larger. Is small. According to the third embodiment, it is possible to obtain the same operational effects as those of the first embodiment.

  Further, in this case, aramid paper having a relatively high frictional resistance subjected to calendering at a low pressure is used as a base material layer, and one surface thereof (a surface located on the outer peripheral side of the stator core 3) is an outer layer having a high frictional resistance. Further, only the other surface (the surface located on the inner peripheral side of the stator core 3) may be treated as a fluid paraffin coating to form an inner layer with reduced frictional resistance. Even in this case, a two-layer structure of a plurality of layers including an outer layer having a high frictional resistance and an inner layer having a low frictional resistance can be configured, and the same operational effects as those of the first embodiment can be obtained.

(Fourth embodiment)
FIG. 8 shows a fourth embodiment, which differs from the first embodiment in the following points.
In the interphase insulating paper main body 15 of the fourth embodiment, a heat-resistant insulating paper made of aramid paper that has been subjected to calendering treatment is used as a base material layer 15a in the same manner as the intermediate layer 8a, and one surface of the base material layer 15a ( On the outer peripheral surface of the stator core 3, for example, short fibers 16 made of resin or rubber are electrostatically implanted to form an outer layer 15 b with increased surface frictional resistance. And the base material layer 15a itself located in the inner peripheral side of the stator core 3 is made into the inner layer 15c, and the two-layer structure which is multiple layers is comprised. Here, in the outer layer 15 b, the electrostatically implanted short fibers 16 are increased in the direction of increasing the friction coefficient with the magnet wire of the coil end 6 in the expanding direction of the coil end 6, that is, toward the stator core 3. The frictional force generated between the coil end 6 and the magnet wire is directional by pushing it down in the direction. For example, in FIG. 8, the frictional force increases when the magnet wire moves in the right direction, and the frictional force decreases when it moves in the left direction.

  Here, the effects of the fourth embodiment will be described with reference to FIG. 2 (in this case, the interphase insulating paper main body 8 is the interphase insulating paper main body 15). At the time of forming and compressing the coil end 6, since the coefficient of friction between the coil end 6 (V) and the interphase insulating paper main body 15 in the expanding direction is large, the interphase insulating paper main body 15 follows the movement of the coil end 6 (V). Also move. However, when the coil end 6 (V) moves in the direction opposite to the expansion direction (molding compression direction) due to the spring back of the coil end 6 (V), the coil end 6 (V) and the interphase insulating paper main body 15 Since the friction coefficient in the direction opposite to the spreading direction is small, the interphase insulating paper main body 15 does not follow the movement of the coil end 6 (V). Therefore, it is possible to prevent the position of the interphase insulating paper main body 15 (interphase insulating paper 7) from being shifted or torn even by the spring back of the coil end 6 (V).

  As described above, according to the interphase insulating paper of the rotating electrical machine of the present embodiment, in the interphase insulating paper main body constituted by a plurality of layers, the surface (outer layer) located on the outer peripheral side of the stator core is the stator core. The friction coefficient between the coil end and the magnet wire is larger than the surface (inner layer) located on the inner peripheral side. That is, when the interphase insulating paper main body and the magnet wire are brought into contact with each other, the outer layer is less slippery than the inner layer. For this reason, when the coil end is expanded and compressed when the coil end is formed, the outer peripheral side (outer layer side) where the deformation amount of the coil end is small in the interphase insulating paper is difficult to slip, and follows the movement of the coil end. On the other hand, the inner peripheral side (inner layer side) where the deformation amount of the coil end is large is slippery and does not follow the movement of the coil end. Thereby, since the front and back surfaces of the interphase insulating paper main body are not pulled in different directions, wrinkles and tearing of the interphase insulating paper can be prevented.

  The interphase insulating paper for a rotating electrical machine described above and the rotating electrical machine using the same are not limited to the above-described embodiment, and can be applied by appropriately changing to various embodiments without departing from the gist thereof. .

  In the drawings, 1 is a stator, 2 is a slot, 3 is a stator core, 5 is a stator coil, 6 is a coil end, 7 is interphase insulating paper, 8, 13, 14, and 15 are interphase insulating paper bodies, 8a, 14a is an intermediate layer, 8b, 13b, 14b and 15b are outer layers, 8c, 13c, 14c and 15c are inner layers, and 9 is a connecting strip.

Claims (6)

A pair of interphase insulating paper bodies formed in a shape that can insulate between the coil ends of the stator coils of a plurality of phases at both axial ends of the stator core;
A connecting strip that is provided so as to connect the pair of interphase insulating paper main bodies and is located in a slot of the stator core;
The interphase insulating paper body is composed of a plurality of layers, and the coefficient of friction between the outer layer of the plurality of layers located on the outer peripheral side of the stator core and the magnet wire of the coil end is the inner peripheral side of the stator core. An interphase insulating paper for a rotating electrical machine, characterized in that the coefficient of friction is larger than the coefficient of friction between the inner layer located at the coil and the magnet wire at the coil end.   The interphase insulating paper main body has an intermediate layer, and the outer layer is attached to one surface of the intermediate layer and the inner layer is attached to the other surface to form a three-layer structure. The interphase insulating paper for a rotating electrical machine according to 1.   2. The interphase insulating paper for a rotating electrical machine according to claim 1, wherein the interphase insulating paper main body has a two-layer structure in which the outer layer and the inner layer are bonded together.   The interphase insulating paper main body has an intermediate layer, one surface of the intermediate layer is subjected to a friction increasing treatment to form the outer layer, and the other surface is subjected to a friction reducing treatment to form the inner layer. The interphase insulating paper for rotating electrical machines according to claim 1.   The interphase insulating paper main body has an intermediate layer, and one surface of the intermediate layer is subjected to a surface treatment for increasing a coefficient of friction with the magnet wire of the coil end in the expanding direction of the coil end, and the outer layer and The interphase insulating paper for a rotating electric machine according to claim 1, wherein the interphase insulating paper is used.   A rotary electric machine using the interphase insulating paper according to any one of claims 1 to 5.

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