JP2011062040A - Rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce manhour required for insulating a coil end. <P>SOLUTION: One coil end 60 of a stator coil 40 is provided with coil conductors 42U, 42V, and 42W for input/output to/from stator coil extensions of stator coils of U, V, W phases and with an extended coil conductor 41 for neutral point connection. The stator coil extensions are bent at ends of slots 22 of a stator core 16, and extended as diagonal portions 61. Each diagonal portion 61 is coated with a uniform insulating powder film 62 to ensure a sufficient insulation breakdown voltage. The insulating powder film 62 is made of an epoxy resin, and is formed by electrostatic powder coating, fluidized bed coating, etc. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rotating electrical machine (segment rotating electrical machine) that uses a segment conductor as a stator winding.

  The segment-type rotating electrical machine has a stator core having a large number of slots opened on the inner peripheral side, and a plurality of substantially U-shaped segment conductors are inserted into each of the slots. As a structure for preventing corona discharge between coils in a high-voltage rotating electrical machine, for example, a structure described in Patent Document 1 is known. In the rotating electrical machine described in Patent Document 1, a structure in which powder coating is applied to the outer peripheral surface of the coil at the coil end portion, or a structure in which insulating paper is inserted between the heat-shrinkable tube and the coil has been proposed.

JP 2004-64989 A

  The rotating electrical machine of Patent Document 1 has a problem in that work efficiency is low and productivity is low because insulating powder coating is applied to the entire surface of each of the substantially U-shaped segment conductors existing on the outer peripheral surface of the coil at the coil end portion. there were.

(1) A rotating electrical machine according to the invention of claim 1 includes a stator having a stator winding wound around a slot of a stator core, and a rotor rotating with respect to the stator. The stator winding of the rotating electrical machine according to claim 1 includes at least a winding main portion constituted by a segment conductor and an input / output coil conductor constituted by a coil conductor.
For each phase, the winding main part inserts a plurality of substantially U-shaped segment conductors into the slot from one end surface side of the stator core, and on the one end surface side and the other end surface side of the stator core. The coil end is wound by welding the joining end portions on the other end face side of the segment conductors to form a coil end.
The coil conductor for input / output is inserted into one of the slots from one end surface side of the stator core for each phase, and the winding start end of the winding main part of each phase on the other end surface side of the stator core Are connected to each other, and input / output terminals of respective phases are connected to one end face side of the stator core.
And among the said input / output coil conductors for each phase, an insulating coating is provided on the coil conductor at the coil end on the one end face side of the stator core.
(2) According to the invention of claim 2, in the rotating electrical machine according to claim 1, the stator winding further includes a neutral point connection coil conductor, and the neutral point connection coil conductor of the stator core Inserted into one of the slots for each phase from one end face side, and connected to the winding end of the winding main part of each phase on the other end face side of the stator core. The neutral point of each phase is connected on the end face side, and the coil conductor at the coil end on the one end face side of the stator core among the coil conductors for the neutral point connection for each phase is also covered with an insulation coating. It is provided.
(3) According to a third aspect of the present invention, in the rotating electric machine according to the second aspect, the insulating coating is generated between the input / output coil conductor and the neutral point connection coil conductor in a different phase. It is formed by the insulating member which has the thickness which prevents the corona discharge which may carry out.
(4) According to a fourth aspect of the present invention, in the rotary electric machine according to the second aspect, the input / output coil conductor and the neutral point connection coil conductor are different in phase at the coil end on the one end face side of the stator core. And the insulation coating is provided on the skewed portion of the input / output coil conductor and the neutral point connecting coil conductor, and in the skewed portion, Corona discharge that may occur between segment conductors of different phases is prevented.
(5) According to a fifth aspect of the present invention, in the rotating electric machine according to any one of the second to fourth aspects, the insulating coating is provided on a surface of the input / output coil conductor and the neutral point connection coil conductor. It is an insulating powder coating coating in which an insulating powder is coated.
(6) According to a sixth aspect of the present invention, in the rotating electric machine according to any one of the second to fourth aspects, the insulating coating covers surfaces of the input / output coil conductor and the neutral point connection coil conductor. It is an insulating tube provided so as to cover it.
(7) The invention of claim 7 is the rotating electrical machine according to claim 6, wherein the insulating tube is a heat-shrinkable tube.
(8) The invention of claim 8 is the rotating electrical machine according to any one of claims 2 to 7, wherein each of the phases is a three-phase UVW, and the input / output coil conductor and the neutral point connection Each of the coil conductors for use is three coil conductors, and the skewed portion is in contact with an adjacent segment conductor via the insulating coating.

  According to the present invention, since the insulating coating is applied only to the coil conductor that may generate the inter-phase corona discharge at the coil end, the number of insulation processing steps and the insulating material can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing which shows the whole structure of 1st Embodiment of the rotary electric machine by this invention. The perspective view which shows the structure of the stator of the rotary electric machine of FIG. The perspective view for 1 phase winding of the rotary electric machine of FIG. The partial detail perspective view of the stator structure of the rotary electric machine of FIG. The block diagram which shows the structure of the vehicle carrying the rotary electric machine of FIG. The partial detail perspective view of the stator structure of 2nd Embodiment figure of the rotary electric machine by this invention.

Embodiments of a rotating electrical machine according to the present invention will be described below in detail with reference to the accompanying drawings.
[First Embodiment]
The rotating electrical machine according to the present invention is suitable for use in hybrid vehicles and electric vehicles. As shown in FIG. 5, in a hybrid vehicle, for example, a front wheel FW, FW is connected to an engine ENG via a transmission TM, and a motor (rotary electric machine) 100 is connected to the engine ENG and the rear wheels RW, RW, respectively. 100 'is connected. The driving force generated by the engine ENG and the rotating electrical machine 100 is shifted by the transmission TM, and the driving force is transmitted to the front wheel side driving wheel FW. In driving the rear wheel, the rotating electrical machine 100 ′ disposed on the rear wheel side and the rear wheel side driving wheel RW are mechanically connected to transmit the driving force.

  The rotating electrical machine 100 starts the engine ENG, and collects the power running that generates the driving force and the energy at the time of vehicle deceleration as regenerative energy according to the traveling state of the vehicle. The driving and power generation operation of the rotating electrical machine 100 are controlled by the power converter PC so that the torque and the rotational speed are optimized in accordance with the driving situation of the vehicle. The electric power necessary for driving the rotating electrical machine 100 is supplied from the battery BA via the power converter (inverter) PC. Further, when the rotating electrical machine 100 is in a power generation operation, the battery BA is charged with electrical energy via the power converter PC.

  Here, the rotating electrical machine 100, which is a driving force source on the front wheel side, is disposed between the engine ENG and the transmission TM (FIG. 5) or mounted in the transmission TM. As the rotating electric machine 100 ′ that is the driving force source on the rear wheel side, the same one can be used, and a rotating electric machine having another general configuration can also be used.

  As shown in FIG. 1, the periphery of the rotating electrical machine 100 is surrounded by a case 130. Here, when the rotating electrical machine 100 is disposed between the engine and the transmission, the case 130 includes an engine case or a transmission case. Further, when the rotating electrical machine 100 is mounted in the transmission, the case 130 is configured by a transmission case.

The rotating electrical machine 100 is a three-phase synchronous motor with a built-in permanent magnet, and is required to have a small size and a high output. The rotating electrical machine 100 operates as an electric motor by supplying a three-phase alternating current to the stator winding 40 (FIGS. 2 to 4), and operates as a generator when the rotating electrical machine 100 is driven by the engine. Outputs three-phase AC generated power.
When operating as a generator, the current output from the stator winding 40 is smaller than that when operating as an electric motor (for example, 100 A). The rotating electrical machine 100 is a three-phase synchronous motor with a built-in permanent magnet, and is required to have a small size and a high output.

  The rotating electrical machine 100 includes a rotor 10, a stator 20, and a housing 50. The rotor 10 includes a permanent magnet 18 and is disposed on the inner peripheral side of the cylindrical stator 20 via a gap. Has been placed. The rotor 10 is fixed to a shaft 12, and both end portions of the shaft 12 are rotatably supported by bearings 14A and 14B. The outer periphery of the stator 20 is fixed to the inner periphery of the housing 50, and the outer periphery of the housing 50 is fixed to the inner periphery of the case 130.

  The rotating electrical machine 100 is cooled by a refrigerant RF such as insulating oil. Therefore, a reservoir portion 21 for the refrigerant RF is formed at the bottom of the case 130, and the lower portion of the stator 20 is immersed in the refrigerant RF accumulated in the reservoir portion 21. The refrigerant RF accumulated in the reservoir portion 21 is sucked by a pump (not shown), and discharged from the refrigerant outlets 154A and 154B formed in the upper part of the case 130 via the refrigerant passage 153.

  The refrigerant outlets 154 </ b> A and 154 </ b> B are provided at several locations in the circumferential direction of the stator 20 at the upper part of the coil end portion 60 of the stator winding of the stator 20. The refrigerant RF discharged from the refrigerant outlets 154 </ b> A and 154 </ b> B is directly blown to the coil end portions 60 at both ends of the stator winding 40.

  As shown in FIGS. 2 and 4, a three-phase stator winding 40 of U phase, V phase, and W phase is wound around the stator core 16 of the stator 20 in the rotating electrical machine 100 by distributed winding. Yes. On the inner periphery of the stator core 16, for example, 72 slots 22 extending in parallel to the central axis are formed at equal intervals in the circumferential direction, and a three-phase stator of U phase, V phase, and W phase is formed. The winding 40 is inserted into the slot 22 while being insulated by insulating paper (slot liner) 24. The slot liner 24 is disposed so as to wrap around the stator winding 40 in order to prevent the stator winding 40 and the stator core 16 from approaching and short-circuiting.

  Note that the rotating electrical machine 100 shown in FIG. 2 is, for example, a 2Y motor including two systems of three-phase AC, and a total of six U, V, and W stator main portions are provided. Therefore, from the stator winding 40, two input / output coil conductors 42U, 42V, and 42W are provided from the six coil winding start ends of the two systems in each phase, and six coil windings in each of the two systems. Six neutral point connection conductors 41 are drawn out from the end portion. The three conductors that are the neutral point connection conductors 41 of each phase are connected by the coil end portion 60.

  For example, the stator core 16 is formed by punching or etching a magnetic steel sheet having a thickness of about 0.05 to 1 mm to form a stator core laminate (not shown), and laminating the stator core laminate. Composed. On the inner peripheral side of the stator core laminate, radial recesses and projections are formed at equally spaced positions in the circumferential direction during molding, and the recesses are continuous when the stator core laminate is laminated. The slots 22 are formed by arranging them in a regular manner. Teeth 23 are formed by continuously arranging convex portions at positions between the slots 22.

  Next, the stator winding 40 will be described with reference to FIG. In the present embodiment, a three-phase stator winding is provided. However, in order to facilitate understanding, the stator winding 40 of only one system of one phase is shown in FIG. And the slot liner 24 is omitted.

  The stator winding 40 has a substantially U-shaped segment conductor 28 one phase at a time, a central portion 28C disposed in one coil end portion 60, and both end portions 28E and 28E of the segment conductor 28 disposed in the other coil end portion. A total of six windings are closely attached to the stator core 16 and are formed by sequentially welding at 60. As the segment conductor 28, for example, a rectangular wire having a substantially rectangular cross section and a rectangular cross section whose outer periphery is covered with an insulating film is used. The rectangular wire is wound so that the rectangular cross section of the segment conductor is longer in the circumferential direction of the stator core 16 and shorter in the radial direction of the stator core 16 in each slot.

The configuration of the stator winding 40 will be described in more detail.
First, a plurality of segment conductors 28 formed in advance so that a rectangular wire having a rectangular cross section is formed in a substantially U shape are inserted so as to be stacked in the radial direction of a plurality of slots 22 provided in the stator core 16. . A plurality of substantially U-shaped segment conductors are inserted every predetermined number of slots instead of adjacent slots. Thereafter, the end portions (end portions on the opposite U-shape) of the segment conductors 28 are alternately bent, and the end portions 28E of the adjacent segment conductors 28 are welded while being alternately bent while removing a part of the insulating film. Connect sequentially.

  Hereinafter, a portion of the stator winding 40 that is configured for each phase by the continuation of the segment conductors 28 is referred to as a “stator winding main part”.

  As shown in FIGS. 2 to 4, one coil end portion 60 of the stator winding 40 has input / output coil conductors 42 </ b> U, 42 </ b> V, 42 </ b> W and neutral points of the stator winding 40 of each of the UVW three phases. The connection conductor 41 is drawn out. That is, the stator winding 40 connects the input / output coil conductors 42U, 42V, 42W and the neutral point connection conductor 41 to the respective main portions of the U-phase, V-phase, and W-phase stator windings. Configured.

  Hereinafter, the input / output coil conductors 42U, 42V, 42W and the neutral point connection conductor 41 are collectively referred to as “stator winding lead portions”. The stator winding lead portion is inserted into one slot 22 while being connected to one end portion 28E of the segment conductor 28, extends in the axial direction of the stator core 16, and further at the end portion of the slot 22 the stator core. 16 is bent along the end face 16F.

  The end portion 28E of the segment conductor 28 is partially removed from the insulating film, but is arranged at an appropriate distance from the side surface of the case 130, and a sufficient withstand voltage is guaranteed.

  The stator winding lead portion is bent at the end of the slot 22 of the stator core 16, that is, at the coil end portion 60 side, and then along the coil end side end face 16 </ b> F of the stator core 16. The inclined portion (end surface extending portion) 61 extends in a direction inclined with respect to the radial direction. The skewed portion 61 extends along the end face 16F so as to overlap the main portion of the stator winding on the outer side in the rotation axis direction. It is also possible to extend the end surface extending portion 61 in the radial direction of the stator core 16.

  The input / output coil conductors 42U, 42V, 42W are further raised from the skewed portion 61 in the axial direction substantially orthogonal to the end face 16F, and provided with power input / output terminals at the ends. The input / output coil conductors 42U, 42V, 42W are connected to the power converter PC via the power input / output terminals. On the other hand, the neutral point connection conductor 41 extends along the end face 16F, and three lines of each phase are connected at the end.

  In the skewed portion 61, the conductors of the respective phases of the stator winding lead portion are relatively close to each other and overlap with the segment conductors of each phase of the main portion of the stator winding with an insulating gap. Sufficient withstand voltage is required between them. Furthermore, since the stator winding lead portion is disposed closer to the inner surface of the case 130 than the main portion of the stator winding, a sufficient withstand voltage is required for the inner surface of the case 130. Therefore, the skewed portion 61 connected to the stator winding lead portion of the stator winding 40 is provided with an insulating powder coating film 62, and the skewed portion 61 ensures a sufficient withstand voltage.

  The insulating powder coating film 62 is, for example, an epoxy resin film, and the insulating powder coating film 62 is applied by a method such as an electrostatic powder coating method or a fluidized immersion coating method. The insulating powder coating film is coated at a thickness substantially equal to the distance (gap) C / 2 between adjacent coil conductors at the coil end portion 60. The film thickness is, for example, about 0.2 mm to 1.0 mm. Thereby, a gap (gap) between the coil conductors in the skew portion 61 is filled, and the coil conductor of the stator winding lead portion in the skew portion 61 is reliably supported.

  That is, the stator winding lead portion is a coil conductor inserted into one slot for each phase, and the coil end portion 60 is drawn in a cantilever state, so that the support of the coil conductor may become unstable. is there. If an insulating powder coating is formed on the coil conductor in the skewed portion 61 of the coil end portion 60 of the stator winding lead portion as in this embodiment, the adjacent coil conductor on the coil end portion 60 side is stabilized. Supported.

  In recent years, rotating electric machines for hybrid vehicles and electric vehicles are used at a high voltage exceeding 100 V, or a high voltage of 400 V to 600 V, so that the insulating powder coating film is not defined by the gap C, Use a thickness that guarantees dielectric strength.

  The coil conductors, which are the main part of the stator winding, are arranged at appropriate intervals by the slots 22, insulated by the slot liner 24, and further ensured a sufficient distance from the case 130. It is enough.

As described above, according to the rotating electrical machine of the present embodiment, the following operational effects can be achieved.
(1) A conventional example in which all the coil conductor surfaces of the coil end portion 60 of the main portion of the stator winding are coated by insulating the stator winding lead portion of the coil end portion 60 with the insulating powder coating film 62. In comparison, the painting area and the number of painting steps are greatly reduced, and the manufacturing cost can be reduced.
For example, if the number of segment conductors is 132 and the number of stator winding lead portions (the number of coil conductors) is 12, the number of painted parts is reduced to about 9%.
(2) Compared to the conventional example, since the coating film forming range is slight, the coil end portion 60 of the stator winding 40 can be compressed in the axial direction and the rotating electrical machine 100 can be downsized. Can do.

(3) Although each coil conductor of the stator winding lead portion is supported by one slot 22, the gap between the coil conductors in the skew feeding portion 61 is filled with the insulating powder coating film 62. The skewed portion 61 is supported in contact with the coil conductor of a different phase, and the stator winding lead portion is firmly supported. Thereby, the rigidity of the stator winding 40 is increased, the vibration of the rotating electrical machine 100 is suppressed, and a short circuit accident caused by the vibration can be prevented. In addition, each coil conductor of the stator winding lead portion of the conventional example is cantilevered, and the support state is unstable compared to the main portion of the stator winding.

(4) By filling the gap of the coil conductor of the stator winding lead portion with the insulating powder coating film 62, the coil end portion 60 becomes planar, and the product shape of the stator 20 becomes stable.

[Second Embodiment]
Next, a second embodiment of the rotating electrical machine according to the present invention will be described with reference to FIG. In the figure, the same or corresponding parts as those of the first embodiment are denoted by the same reference numerals and the description thereof is omitted.

  In the second embodiment, an insulating tube is used instead of the insulating powder coating film 62 in the first embodiment.

  As shown in FIG. 6, the coil conductor in the skewed portion 61 of the stator winding lead-out portion is covered with an insulating tube 63, and a sufficient withstand voltage is ensured as in the first embodiment. The insulating tube is a heat-shrinkable tube, and shrinks to a predetermined thickness by heating after coating, and tightly coats the coil conductor in the skew portion 61.

  When the insulating tube 63 is attached to the inclined portion 61, the insulating tube 63 is heated after being inserted into the slot 22 in a state where the insulating tube 63 is fitted to the coil conductor. The thickness of the insulating tube 63 after heat shrinkage is set substantially equal to the gap C, fills the gap C, and supports the skewed portion 61 while making the end surface of the stator 20 planar.

As a result, the same effect as in the first embodiment can be obtained.
The insulation coating for the insulation treatment for the stator winding lead portion is not limited to the insulating powder coating film 62 and the insulating tube 63, and any insulation that can cover the coil conductor such as an adhesive insulating sheet. Material can be used.

  The embodiment described above is an example, and the present invention can be implemented in various forms. That is, the rotating electrical machine of the present invention includes a stator having a stator winding wound around a slot of a stator core, and a rotor that rotates with respect to the stator, and includes the following configurations (1) to (1) to (3) is provided, and the rotating electrical machine may be configured in any form within this range.

(1) The stator winding is formed by inserting a plurality of substantially U-shaped segment conductors 28 into the slots 22 from one end surface side of the stator core 16, and coil ends on one end surface side and the other end surface side of the stator core 16. In this way, the joint end portion 28E on the other end face side of the segment conductor 28 is wound with each other to have a winding main portion for each phase.
(2) The stator winding is also inserted into one of the slots 22 for each phase from one end face side of the stator core 16, and the winding of the main part of the winding of each phase is placed on the other end face side of the stator core 16. Each has an input / output coil conductor 42 </ b> U to 42 </ b> W for each phase that is connected to the start end and that is connected to the input / output terminals of each phase on one end face side of the stator core 16.
(3) Of the input / output coil conductors 42U to 42W for each phase, an insulating coating is provided only on the coil conductor of the coil end 60 on the one end face side of the stator core 16.

  Therefore, in the embodiment, both the input / output coil conductor and the neutral point connection coil conductor are coated with insulation. However, the present invention does not cause a corona discharge between the neutral point connection coil conductor and a different phase coil conductor. The present invention can also be applied to a rotating electric machine arranged so as not to exist. In this rotating electrical machine, it is only necessary to apply an insulating coating only to the input / output coil conductors. Furthermore, the present invention can also be applied to a rotating electrical machine that does not include a neutral point connection coil conductor. This rotating electrical machine has a structure in which an input / output coil conductor causes a corona discharge with an adjacent different-phase coil conductor. The coil conductor is provided with an insulating coating.

  Moreover, in the rotary electric machine of the said embodiment, it had two three-phase alternating current electric power systems, and connected them 2Y. The present invention is also applied to a rotating electrical machine having a Δ connection or a rotating electrical machine having one three-phase AC power system. Further, the present invention is applied to an AC rotating electrical machine having two or more phases, and is not limited to an automotive rotating electrical machine.

C Gap 16 Stator core 20 Stator 22 Slot 28 Segment conductor 40 Stator winding 41 Coil conductor for neutral point connection 42 Coil conductor for input / output 61 Skew portion 62 Insulating powder coating film 63 Insulating tube 100 Rotating electric machine

Claims (8)

A stator having a stator winding wound in a slot of the stator core;
In a rotating electrical machine comprising a rotor that rotates relative to the stator,
The stator winding includes a plurality of substantially U-shaped segment conductors inserted into the slot from at least one end surface side of the stator core, and coil ends are formed on the one end surface side and the other end surface side of the stator core. A winding main part for each phase wound by welding the joint end on the other end face side of the segment conductor to each other,
Inserted into one of the slots for each phase from one end surface side of the stator core, respectively connected to the winding start end of the winding main portion of each phase on the other end surface side of the stator core, An input / output coil conductor for each phase to which the input / output terminals of each phase are respectively connected on one end surface side of the stator core;
An electric rotating machine comprising an insulating coating provided on a coil conductor at a coil end on the one end face side of the stator core among the input / output coil conductors for each phase. The rotating electrical machine according to claim 1, wherein
The stator winding further comprises a coil conductor for neutral point connection,
The coil conductor for neutral point connection is inserted into one of the slots for each phase from one end surface side of the stator core, and the winding main portion of each phase is wound on the other end surface side of the stator core. Each is connected to the end, and the neutral point of each phase is connected on one end face side of the stator core,
Of the coil conductors for neutral point connection for each phase, an insulating coating is also provided on the coil conductor at the coil end on the one end face side of the stator core. In the rotating electrical machine according to claim 2,
The insulating coating is formed of an insulating member having a thickness that prevents corona discharge that may occur between the input / output coil conductor and the neutral point connection coil conductor between the segment conductors of different phases. Rotating electric machine characterized by that. In the rotating electrical machine according to claim 2,
The input / output coil conductor and the neutral point connection coil conductor have a skew portion that skews across a segment conductor of a different phase at the coil end on the one end face side of the stator core,
The insulating coating is provided on the skewed portions of the input / output coil conductor and the neutral point connection coil conductor, and generates corona discharge that may occur between the segment conductors of different phases in the skewed portion. A rotating electrical machine characterized by preventing. The rotating electrical machine according to any one of claims 2 to 4,
The rotating electrical machine characterized in that the insulating coating is an insulating powder coating coating in which insulating powder is coated on the surfaces of the input / output coil conductor and the neutral point connection coil conductor. The rotating electrical machine according to any one of claims 2 to 4,
The rotating electrical machine characterized in that the insulating coating is an insulating tube provided so as to cover surfaces of the input / output coil conductor and the neutral point connection coil conductor. The rotating electrical machine according to claim 6,
The rotating electrical machine characterized in that the insulating tube is a heat shrinkable tube. The rotating electrical machine according to any one of claims 2 to 7,
Each of the phases is a UVW three-phase,
The input / output coil conductors and the neutral point connection coil conductors are respectively three coil conductors, and the oblique portions are in contact with adjacent segment conductors via the insulating coating. Rotating electric machine.

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