JP2007312564A - Stator of rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stator of a rotary electric machine capable of ensuring the insulation properties between a stator coil and a stator core. <P>SOLUTION: The stator 30 of an MG10 comprises: the cylindrical stator core 31 in which a plurality of slots 35 are formed circumferentially; and a stator coil 32 that is formed by a segment 33 having an insulating coating layer 39 at the outer periphery and is stored in the slot 35. In this case, the periphery of the slot 35 is set to be a curved surface 37a on both the end faces of the stator core 31. Thus, damage is suppressed in an insulating coating layer 39 provided at the outer periphery of the segment 33 since a contact at the side of the stator core 31 is the curved surface 37a, even if the stator coil 32 comes into contact with the periphery of the slot 35 on the end face of the stator core 31. Consequently, insulation properties can be secured between the stator coil 32 and the stator core 31. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a stator for a rotating electrical machine.

  [DESCRIPTION OF RELATED ART] Conventionally, the stator of the segment joining type rotary electric machine which inserted the some conductor segment in the slot of the stator core, and joined each of the some conductor segment, and formed the stator winding | coil has been proposed ( For example, see Patent Document 1). In this stator, a plurality of substantially U-shaped conductor segments are inserted from one end face side of the stator core, and then end portions on the non-insertion side are joined together to form a stator winding.

  In a rotating electrical machine, it is important to ensure insulation between the stator core and the stator winding, and various measures have been devised for ensuring insulation. In the stator described in Patent Document 1, the stator core is formed by laminating steel sheet sheets in which concave portions corresponding to the slots are punched using a press die, and the direction of the flash generated by the punching is in one direction. Steel sheet sheets are laminated so as to be aligned. The insertion direction of the conductor segment is the same as the punching direction of the steel sheet. Thereby, since the conductor segment is inserted along the direction in which the beam extends, it is possible to prevent the insulating coating provided on the conductor segment from being damaged during insertion.

However, in the stator described in Patent Document 1, the flash extends toward the outside of the slot at the end surface on the side opposite to the insertion of the conductor segment in the stator core. Therefore, after the conductor segment is inserted, when the conductor segment comes into contact with the end of the slot opposite to the insertion side, the insulation film of the conductor segment is easily damaged, and the insulation between the stator core and the stator winding May not be secured.
JP 2000-92801 A

  The present invention has been made in view of the above problems, and has as its main object to provide a stator of a rotating electrical machine that can ensure insulation between a stator winding and a stator core. is there.

  Hereinafter, means and the like effective for solving the above-described problems will be described while showing functions and effects as necessary.

  According to the first aspect of the present invention, a stator winding formed by a cylindrical stator core having a plurality of slots formed in the circumferential direction and an electric conductor having an insulating coating layer on the outer periphery and accommodated in the slots. In the stator of the rotating electrical machine, the peripheral edge portion of the slot on both end faces of the stator core is a curved surface.

  As a result, even if the electric conductor constituting the stator winding contacts the peripheral edge portion of the slot on the end surface of the stator core, the contact portion on the stator core side is a curved surface, so that it is provided on the outer periphery of the electric conductor. Damage to the insulating coating layer can be suppressed. As a result, it is possible to ensure insulation between the stator winding and the stator core.

  According to a second aspect of the present invention, in the stator of the rotating electrical machine in which the stator iron core is formed by stacking the steel sheet sheets in which the shape of the slot is punched, the surface on the inlet side in the punching direction of the steel sheet is formed. It is characterized by being laminated so as to be the end face of the stator core.

  When the shape of the slot is formed by punching the steel sheet, the entrance side in the punching direction is deformed, so that a curved surface portion is formed on the entrance side in the punching direction at the peripheral edge of the recess corresponding to the shape of the slot. Thereby, the peripheral part of the slot in the end surface of a stator core can be made into a curved surface by making the surface by the side of the punching direction of a steel plate sheet into the end surface of a stator core.

  In the invention according to claim 3, the steel sheet is laminated so that a beam extends from both ends of the stator core toward the center side, and in the stator core, the axial direction of the stator core In the center of about 1/3, the flashes extending in opposite directions are opposed to each other, and a flashing portion is provided.

  Since the stator winding is formed by bending the electric conductor coming out from the end face of the stator core in the circumferential direction, it may be inclined in the circumferential direction even in the slot. In this case, if the flashing portion is located near the center in the axial direction in the slot, it is easy to secure a gap between the electric conductor arranged in the slot and the tip of the flashing portion. As a result, it is possible to suppress the occurrence of corona discharge between the electric conductor and the tip of the joining portion.

  The invention according to claim 4 is characterized in that the insulating coating layer is thicker than the protruding length of the flash. The invention according to claim 5 is characterized in that the insulating coating layer is thicker than the sum of the circumferential variation width of the steel sheet and the projection length of the flash. As a result, even when the insulating coating layer of the electric conductor is damaged by the step of the inner wall surface of the slot due to flash or stacking variation, the possibility that the electric conductor is exposed due to the damage is reduced. As a result, it is possible to prevent dielectric breakdown from occurring between the stator core and the stator winding. The insulating coating layer is preferably thicker than the maximum value of the maximum protrusion length of the flash in the stator core and the sum of the variation width in the circumferential direction of the steel sheet and the protrusion length of the flash. As a result, it is possible to ensure insulation at a site where dielectric breakdown is most likely to occur.

  The invention according to claim 6 is characterized in that the insulating coating layer is formed by providing an enamel layer on the outer periphery of the electric conductor and providing an extrusion coating resin layer on the outer periphery of the enamel layer. With this configuration, it is easy to form a thick insulating coating layer.

  The invention according to claim 7 is characterized in that a plurality of conductor segments are used as the electrical conductors, and ends of the plurality of conductor segments are joined together to form the stator winding. Thereby, since it becomes easy to arrange | position the electrical conductor which forms a stator coil | winding in a slot, manufacture of a stator coil | operator becomes easy.

  The invention according to claim 8 is characterized in that a cross-sectional shape of the conductor segment in the slot is a substantially rectangular shape along the slot shape. Thereby, it becomes easy to increase the space factor of the electric conductor in the slot.

  The invention according to claim 9 is characterized in that the stator according to any one of claims 1 to 8 is applied to a rotating electrical machine mounted on a vehicle. When the rotating electrical machine is mounted on a vehicle, the stator windings easily come into contact with the peripheral portion of the slot or the like due to vehicle vibration or the like. In this regard, by employing the stator of the present invention, it is possible to suppress dielectric breakdown even in a severe environment such as a vehicle.

  Hereinafter, an embodiment in which the rotating electric machine of the present invention is embodied as a motor generator (MG) 10 for driving a vehicle will be described.

  First, the configuration of the MG 10 of this embodiment will be described. FIG. 1 is a cross-sectional view showing the overall structure of the MG 10 of the present embodiment. FIG. 2 is a circuit diagram of the MG 10. As shown in FIG. 1, the MG 10 of this embodiment includes a housing 11, a rotor 20, and a stator 30.

  The rotor 20 includes a rotating shaft 21, a rotor iron core 22, and a permanent magnet 23. The rotor core 22 is fixed to the rotating shaft 21. The rotating shaft 21 is rotatably supported by the housing 11 through a pair of bearings 12 and 13. A plurality of permanent magnets 23 are embedded in the circumferential direction of the rotor core 22 at a predetermined pitch, and are magnetized so that the polarities of the permanent magnets 23 are alternately different in the circumferential direction. The structure of the rotor 20 can be replaced with various known types such as a winding field type in which a field winding is wound around a Landel pole core.

  The stator 30 is disposed on the radially outer side of the rotor 20. The stator 30 includes a stator core 31 and a stator winding 32. The stator core 31 is cylindrical and is fixed to the inner peripheral surface of the peripheral wall of the housing 11. The stator winding 32 is wound around each slot of the stator core 31. Further, the first coil end portion 32a of the stator winding 32 protrudes in the direction along the rotary shaft 21 from one axial end surface of the stator core 31, and the stator winding from the other axial end surface. 32 second coil end portions 32 b protrude in the direction along the rotation shaft 21.

  As shown in FIG. 2, the stator winding 32 is formed by Y-connecting a U-phase coil 32U, a V-phase coil 32V, and a W-phase coil 32W. The U-phase coil 32U is formed by connecting the circumferential coils U1, U2, U3, U4 in series. Similarly, the V-phase coil 32V is formed by connecting the winding coils V1, V2, V3, and V4 in series. Similarly, the W-phase coil 32W is formed by connecting the winding coils W1, W2, W3, and W4 in series.

  An inverter 41 is connected between the battery 40 and the external lead terminals 320U, 320V, and 320W of each phase coil. The inverter 41 is composed of six power elements 42.

  When the vehicle is driven, the power element 42 is appropriately switched according to an instruction from a controller (not shown), and a three-phase AC voltage is applied from the battery 40 to the stator winding 32 via the inverter 41. The rotor 20 rotates by this applied voltage. A rotating shaft 21 of the rotor 20 is directly connected to an engine crankshaft (not shown) or connected via a clutch, gear, or the like. In the case of direct connection, the engine is started by the rotation of the rotating shaft 21 of the rotor 20. On the other hand, during charging, current flows from the stator winding 32 to the battery 40 due to rotation of the crankshaft and the rotating shaft 21 of the rotor 20. The battery 40 is charged by this current.

  Next, details of the stator 30 will be described.

  As shown in FIG. 3, the stator core 31 is formed by laminating a large number of ring-shaped core sheets 36. Concave portions 37 corresponding to the slots 35 are formed at equal intervals on the inner peripheral side of the core sheet 36. The core sheet 36 is formed by punching a thin steel plate using a press die. In addition, 96 recesses 37 corresponding to the slots 35 are formed so as to accommodate the three-phase stator windings 32 in the slots 35 corresponding to the number of magnetic poles of the rotor 20. By laminating a large number of the core sheets 36, 96 slots 35 in which the multiphase stator windings 32 are accommodated in the circumferential direction are formed, and 96 teeth 34 are formed between the adjacent slots 35. Is done.

  FIG. 4 is a perspective view showing a schematic shape of the basic segment 33 constituting the stator winding 32. As shown in FIG. 4, the stator winding 32 is formed by connecting segments 33 in which an electric conductor having a substantially rectangular cross section (flat rectangular cross section) and having a constant thickness is formed in a substantially U shape. The basic segment 33 includes a large segment 331 and a small segment 332.

  The large segment 331 includes an inner diameter side accommodated portion 331a, an outer diameter side accommodated portion 331b, a turn portion 331c, an inner diameter side open end portion 331d, and an outer diameter side open end portion 331e. The inner diameter side accommodated portions 331a and 332a and the outer diameter side accommodated portions 331b and 332b are accommodated in two slots 35 that are separated from each other by a predetermined magnetic pole pitch (in this embodiment, 12 slots). The inner diameter side accommodated portion 331 a of the large segment 331 is disposed on the innermost diameter side in the slot 35, and the outer diameter side accommodated portion 331 b is disposed on the outermost diameter side in the slot 35. The turn part 331 c connects one end of the inner diameter side accommodated part 331 a and one end of the outer diameter side accommodated part 331 b outside the slot 35. The inner diameter side open end 331d extends out of the slot 35 from the other end of the inner diameter side accommodated part 331a. Similarly, the outer diameter side open end 331e extends out of the slot 35 from the other end of the outer diameter side accommodated part 331b.

  Similarly to the large segment 331, the small segment 332 also has an inner diameter side accommodated portion 332a, an outer diameter side accommodated portion 332b, a turn portion 332c, an inner diameter side open end portion 332d, and an outer diameter side open end portion 332e. . The small segment 332 is disposed so as to be surrounded by the large segment 331. The inner diameter side accommodated portion 332a and the outer diameter side accommodated portion 332b are accommodated in two slots that are separated by a predetermined magnetic pole pitch. The inner diameter side accommodated portion 332a is disposed adjacent to the outer diameter side of the inner diameter side accommodated portion 331a in the slot 35, and the outer diameter side accommodated portion 332b is the inner diameter side of the outer diameter side accommodated portion 331b in the slot 35. It is arranged adjacent to. The turn part 332c connects one end of the inner diameter side accommodated part 332a and one end of the outer diameter side accommodated part 332b outside the slot. The inner diameter side open end 332d extends out of the slot from the other end of the inner diameter side accommodated part 332a. Similarly, the outer diameter side open end 332e extends out of the slot from the other end of the outer diameter side accommodated part 332b.

  FIG. 5 shows a cross-sectional view of the large segment 331. As shown in FIG. 5, the segment 331 is formed by providing an insulating coating 39 on the outer periphery of a conductor portion 33a made of an electric conductor. In this embodiment, an enamel layer 39a is provided on the outer periphery of the conductor portion 33a with a film thickness of about 40 μm, and a polyphenylene sulfide (PPS) resin layer 39b as an extrusion coating resin layer is provided on the outer periphery of the enamel layer 39a with a film thickness of about 70 μm. It has been. The small segment 332 has the same configuration.

  FIG. 6 is a partially developed view of a cross section perpendicular to the axial direction of the stator 30. As described above, the stator winding 32 is formed by connecting the ends of the plurality of basic segments 33. The slots 35 of the stator core 31 accommodate the receiving portions 331a, 331b, 332a, 332b of even-numbered (four in this embodiment) segments 331, 332, respectively. The accommodated portions 331a, 331b, 332a, 332b of the four segments 331, 332 in one slot 35 are arranged from the inner side to the inner end layer X1, the inner middle layer X2, the outer middle layer X3, the outer side in the radial direction of the stator core 31. They are arranged in a line in the order of the end layer X4.

  In this embodiment, an insulator-less configuration in which a sheet-like insulator such as insulating paper is not disposed between the segments 331 and 332 in the slot 35 and the inner wall surface of the slot.

  As described above, the accommodated portions 331a, 331b, 332a, and 332b arranged in each slot 35 are accommodated in other slots 35 that are separated by a predetermined magnetic pole pitch (12 slots in this embodiment). It forms a pair with the parts 331a, 331b, 332a, 332b. In particular, in order to secure and arrange the gaps between the plurality of segments 331 and 332 in the first and second coil end portions 32a and 32b, the received portions 331a and 331a of a predetermined layer in one slot 35 are arranged. 331b, 332a, and 332b are paired with the receiving portions 331a, 331b, 332a, and 332b of other layers in the other slots 35 that are separated by a predetermined magnetic pole pitch.

  For example, as shown in FIG. 6, the accommodated portion 331a of the inner end layer X1 in one slot 35 in the rotating coil U1 is another slot 35 that is one magnetic pole pitch away in the clockwise direction of the stator core 31. It is paired with the accommodated portion 331b of the inner outer end layer X4. Similarly, the accommodated portion 332a of the inner middle layer X2 in one slot 35 in the winding coil U1 is accommodated in the outer middle layer X3 in the other slot 35 that is one magnetic pole pitch away in the clockwise direction of the stator core 31. It is paired with the portion 332b.

  The paired receiving portions 331a, 331b, 332a, 332b are connected by a continuous line (turn portions 331c, 332c) on the first coil end portion 32a side of the stator core 31. Therefore, on the first coil end portion 32a side of the stator core 31, the turn portion 332c that connects the accommodated portion 332b of the inner middle layer X2 and the accommodated portion 332b of the outer middle layer X3 is accommodated in the inner end layer X1. The turn part 331c which connects the part 331a and the to-be-accommodated part 331b of the outer end layer X4 surrounds.

  On the other hand, the accommodation portion 332a of the inner middle layer X2 in one slot 35 in the winding coil U1 is covered by the inner end layer X1 in another slot 35 that is one magnetic pole pitch away in the clockwise direction of the stator core 31. It is also paired with the accommodating portion 331a ′. Similarly, the accommodated portion 331b ′ of the outer end layer X4 in one slot 35 in the winding coil U1 is the outer middle layer X3 in another slot 35 that is one magnetic pole pitch away in the clockwise direction of the stator core 31. It is paired with the accommodated portion 332b.

  Then, on the second coil end portion 32b side of the stator core 31, open end portions 332d, 331d ′, 331e ′, which extend outside the slot 35 from these accommodated portions 332a, 331a ′, 331b ′, 332b, The ends of 332e are joined by welding or the like. Therefore, on the second coil end portion 32b side of the stator core 31, a joint portion connecting the electric conductor of the inner end layer X1 and the electric conductor of the inner middle layer X2, and the electric conductor of the outer middle layer X3 and the outer end layer X4. Are joined in the radial direction.

  The basic segments 33 are regularly arranged in the slots 35 to form the respective winding coils that make two rounds around the stator core 31. In addition, the turn part which connects the 1st round and the 2nd round is comprised by the deformed segment from which the basic segment 33 differs in shape. In addition, the segment that connects the respective winding coils and the segment that forms the lead wire of the stator winding 32 are also formed by deformed segments.

  FIG. 7 is a cross-sectional view taken along the line AA in FIG. 6, and shows a state inside the slot 35. As described above, since the core sheet 36 is formed by punching a thin steel plate, a curved surface portion 37a is formed on the peripheral edge of the recess 37 of each core sheet 36 on the entrance side in the punching direction. Further, a flash 37b extending in the punching direction is formed at the outlet side end in the punching direction. The flash 37 b includes a sharp tip and extends from the lower surface of the core sheet 36 by about 30 μm at the maximum.

  In the stator core 31 of the present embodiment, the core cores 36 are laminated such that burrs 37b extend downward in the upper half of FIG. 6 and flashes 37b extend upward in the lower half of FIG. The sheets 36 are formed by laminating. As a result, curved surface portions 37 a are formed on the peripheral edges of the slots 35 on both end surfaces of the stator core 31. Further, the exit side surfaces of the core sheet 36 in the punching direction face each other in the vicinity of the center in the axial direction of the stator core 31. Then, the flashes 37b formed on the facing core sheets 36 face each other, so that a flashing portion 37c protruding from the inner wall surface of the slot 35 into the slot 35 is formed. The protruding length of the flash 37b at the flashing portion 37c is about 30 μm, similar to the length of each flash 37b.

  Next, the manufacturing process of the stator 30 will be described below.

  (Core Laminating Step) First, a large number of core sheets 36 are laminated to form the stator core 31. At this time, as described above, the core sheet 36 is laminated so that the flash 37b extends in the opposite axial direction from both end face sides of the stator core 31.

  (Insertion step) As shown in FIG. 8, the basic segment 33 is placed on one of the axial end surfaces of the stator core 31 in a state where the turn portion 332c of the small segment 332 is aligned with the turn portion 331c of the large segment 331. Insert from the side. At that time, one accommodated portion 331a of the large segment 331 is disposed on the inner end layer X1 of one slot 35 of the stator core 31, and one accommodated portion 332a of the small segment 332 is disposed on the inner middle layer X2 of one slot 35. The other receiving portion 331b of the large segment 331 is placed on the outer end layer X4 of the other slot 35, which is one magnetic pole pitch clockwise from one slot 35 of the stator core 31, and the other receiving portion 331b of the small segment 332 is. The accommodating portion 332b is also inserted into the outer middle layer X3 of the other slot 35.

  As a result, as shown in FIG. 6, in the one slot 35, the aforementioned receiving portions 331a, 332a, 332b ′, 331b ′ are arranged in a row from the inner end layer X1 side. Here, the accommodated portions 332b ′ and 331b ′ are accommodated portions of the large and small segments 331 and 332 that are paired with the accommodated portions in the other slots 35 that are shifted by one magnetic pole pitch.

  (Bending process) After the segment 33 is inserted, the open end portions 331d and 331e on the outer diameter side and the inner diameter side located on the end layer side in the vicinity of the outlet of the slot 35 on the second coil end portion 32b side are large segments. The 331 is twisted and bent in the opening direction by a half magnetic pole pitch (6 slots in this embodiment). The open end portions 332d and 332e on the outer diameter side and the inner diameter side located in the middle layer are twisted and bent by a half magnetic pole pitch in the direction in which the small segment 332 is closed. As a result, in the second coil end portion 32b, the open end portions 331d, 331e, 332d, 332e of the segments 331, 332 adjacent in the radial direction are inclined in the opposite direction in the circumferential direction. The above operation is performed for the segments 33 of all the slots 35.

  (Jointing Step) Then, in the second coil end portion 32b, the open end 331e ′ of the outer end layer X4 and the open end 332e of the outer middle layer X3, and the open end 332d of the inner middle layer X2 and the inner end layer X1 are opened. The end portion 331d ′ is joined to obtain electrical continuity by means of welding, ultrasonic welding, arc welding, brazing, or the like, and the stator 30 is obtained.

  According to the embodiment described above in detail, the following excellent effects can be obtained.

  The segment 33 is bent in the circumferential direction in the vicinity of the axial outlet of the slot 35. Further, a curved surface portion 37 a is formed on the peripheral edge of the slot 35 on the end surface of the stator core 31. As a result, even if the segment 33 contacts the periphery of the slot 35 in the vicinity of the outlet of the slot 35, the contact portion on the stator core 31 side is a curved surface, so that it is provided on the segment 33 unlike the contact with the sharp part. Damage to the insulating coating 39 can be suppressed. As a result, it is possible to ensure insulation between the stator winding 32 and the stator core 31.

  In particular, in this embodiment, the stator core 31 is formed by laminating the core sheet 36 in which the shape of the slot 35 is punched, and the surface on the inlet side in the punching direction of the core sheet 36 is the end surface of the stator core 31. It is said. Thereby, the periphery of the slot 35 on the end surface side of the stator core 31 can be a curved surface portion 37a. Thus, by setting the stacking direction of the core sheets 36 to a predetermined direction, the peripheral edge of the slot 35 can be a curved surface portion 37a. Therefore, special processing or the like for making the peripheral edge of the slot 35 into the curved surface portion 37a becomes unnecessary.

  Further, the core sheet 36 disposed on the end surface of the stator core 31 is disposed such that the flash 37b generated by the punching extends toward the center of the stator core 31 in the axial direction. Therefore, in the corner portion of the teeth 34 in the stator core 31, the flash 37 b extends along the inner wall surface of the slot without extending toward the outside of the slot 35. Thereby, it is possible to suppress the insulating coating 39 provided on the segment 33 from being damaged by the flash 37b in the vicinity of the outlet of the slot 35 in the axial direction.

  In the present embodiment, the flashing portion 37 c is formed substantially at the center of the slot 35 in the axial direction. The large segment 331 inserted into the slot 35 is bent by twisting the open ends 331d and 331e on the inner and outer diameter sides in the direction in which the U-shaped segment opens. Therefore, as shown in FIG. 6, there is a high possibility that the large segment 331 is positioned obliquely in the slot 35. As a result, it becomes easy to secure a predetermined interval between the segment disposed in the slot 35 and the tip of the joining portion 37c, and corona discharge is generated between the segment and the tip of the joining portion 37c. It becomes possible to deter.

  In the present embodiment, the stator winding 32 is formed by inserting a substantially U-shaped segment 33 into the slot 35 and then joining the ends thereof. By making the electric conductor forming the stator winding 32 into a segment shape, it becomes easy to arrange the segment 33 in the slot 35. Thereby, manufacture of the stator winding | coil 32 becomes easy. Further, the segment 33 has a substantially rectangular cross section, and follows the shape of the slot 35. Thereby, it becomes easy to increase the space factor of the segment 33 (electrical conductor) in the slot 35.

  In the present embodiment, the segment 33 is provided with a double insulating film 39 of an enamel layer 39a and a PPS resin layer 39b. The sum of the thicknesses of the double insulating coating 39 is about 110 μm, which is set to be thicker than the protruding length of the flash 37 b of 30 μm. Thereby, even when the insulating coating 39 of the segment 33 is damaged by the flash 37b, the possibility that the conductor portion 33a of the segment 33 is exposed due to the damage is reduced. As a result, it is possible to prevent dielectric breakdown from occurring between the stator core 31 and the stator winding 32.

  In this embodiment, the insulating coating 39 is formed by the enamel layer 39a and the PPS resin layer 39b as the extrusion coating resin layer. Although it is not easy to make a thick film only by the enamel layer 39a, it is easy to make a thick film by combining the enamel layer 39a and the PPS resin layer 39b to form the double insulating film 39.

  In addition, by adopting the configuration of the present embodiment, it is possible to effectively suppress dielectric breakdown even when the vehicle is mounted, in which vibration or the like may frequently occur. Further, by realizing a high space factor of the electric conductor in the slot as in the present embodiment, it is possible to realize a high output MG 10 suitable for driving a vehicle.

  In addition, as shown in the cross-sectional view showing the state inside the slot 35 in FIG. 9, when the core sheets 36 are stacked, usually, a predetermined stacking variation may occur in the circumferential direction. The maximum value t of the stacking variation in the circumferential direction of the core sheet 36 is about 40 to 50 μm, and the maximum value of the sum of the stacking variation of the core sheet 36 and the protrusion length (about 30 μm) in the circumferential direction of the flash 37 b is about 70. ˜80 μm.

  Also in this case, the thickness of the insulating coating 39 of the segment 33 of this embodiment is about 110 μm, which is set to be larger than the sum of the stacking variation of the core sheet 36 and the projection length of the flash 37 b. Therefore, even when the segment 33 comes into contact with the step or the flash 37b on the inner wall surface of the slot caused by the stacking variation and the insulating coating 39 is damaged, the conductor 33a of the segment 33 may be exposed due to the damage. Get smaller. As a result, it is possible to prevent dielectric breakdown from occurring between the stator core 31 and the stator winding 32.

  In addition, this invention is not limited to the content of description of the said embodiment, For example, you may implement as follows.

  In the first embodiment, the flashing portion 37 c is formed substantially at the center in the axial direction of the slot 35. However, even if the alignment portion 37c is formed at a position in the range of the center 1/3 in the axial direction of the slot 35, a predetermined distance is provided between the segment 33 and the tip end portion of the alignment portion 37c in the slot 35. It is possible to prevent the occurrence of corona discharge by ensuring the above.

  In the above embodiments, the number of slots 35 is 96 corresponding to the number of magnetic poles of the rotor 20. However, the number of slots 35 is not limited to 96, and can be changed according to the number of magnetic poles of the rotor 20.

  In each said embodiment, the extrusion coating resin layer provided in the outer periphery of the enamel layer 39a was formed using PPS resin. However, the extrusion-coated resin layer may be any material that can be extruded, and polypropylene (PP), polymethylpentene (PMP), and the like can also be used.

  In the above embodiments, the stator 30 is formed without using a sheet-like insulator. However, a sheet-like insulator is not used in the slot 35, and a sheet-like insulator is disposed between the radially adjacent segments 331 and 332 in the first and second coil end portions 32a and 32b outside the slot 35. It is good also as composition to do. FIG. 10 shows a perspective view when the above-described configuration is adopted for the second coil end portion 32b of the stator core 31 in which 36 slots 35 are formed. In the stator 30 shown in FIG. 10, the insulating paper 50 is interposed between the segments 33 adjacent to each other in the radial direction in the first and second coil end portions 32a and 32b. By adopting such a configuration, it is possible to increase the reliability of insulation between adjacent segments 33 outside the slot 35 while maintaining a high space factor of the segment (electrical conductor) in the slot 35. Become.

A sectional view showing the whole motor generator structure of a first embodiment. The circuit diagram of the motor generator of a first embodiment. Explanatory drawing of the stator core formed by laminating | stacking the core sheet of 1st embodiment. The perspective view which shows the typical shape of the segment which comprises the stator winding | coil of 1st embodiment. Sectional drawing of the segment of 1st embodiment. The partial schematic sectional drawing of the stator of 1st embodiment. AA line sectional view of Drawing 6. The perspective view which shows the insertion process of the segment with respect to the stator core of 1st embodiment. The partial schematic cross section of the stator of 2nd embodiment. The perspective view by the side of the 2nd coil end part of other embodiments.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Motor generator (MG), 11 ... Housing, 12, 13 ... Bearing, 20 ... Rotor, 21 ... Rotating shaft, 22 ... Rotor core, 23 ... Permanent magnet, 30 ... Stator, 31 ... Stator iron core, 32 ... Stator winding, 33 ... Segment, 34 ... Teeth, 35 ... Slot, 36 ... Core sheet, 37 ... Recessed part, 37a ... Curved part, 37b ... Burr, 37c ... Burr part, 39 ... Insulating coating, 39a ... Enamel layer, 39b. Polyphenylene sulfide (PPS) resin layer.

Claims (9)

A cylindrical stator core having a plurality of slots formed in the circumferential direction;
In a stator of a rotating electrical machine formed by an electric conductor having an insulating coating layer on the outer periphery and having a stator winding accommodated in the slot,
A stator of a rotating electrical machine, wherein peripheral edges of the slots on both end faces of the stator core are curved. In the stator of the rotating electrical machine in which the stator core is formed by laminating steel sheet sheets in which the shape of the slot is punched,
The stator of a rotating electrical machine according to claim 1, wherein the steel sheet is laminated so that a surface on an inlet side in a punching direction is an end surface of the stator core. The steel sheet is laminated so that a flash extends from both ends of the stator core toward the center,
2. The stator iron core according to claim 1, wherein a flashing portion is provided so that the flashes extending in opposite directions face each other at a position in a range of about 1/3 of the axial center of the stator core. The stator of the rotary electric machine according to 2.   The stator for a rotating electrical machine according to claim 3, wherein the insulating coating layer is thicker than a protruding length of the flash.   5. The stator for a rotating electrical machine according to claim 3, wherein the insulating coating layer is thicker than a sum of a circumferential variation width of the steel sheet and a protrusion length of the flash.   The insulating coating layer is formed by providing an enamel layer on the outer periphery of the electrical conductor and providing an extrusion coating resin layer on the outer periphery of the enamel layer. The stator of the described rotating electrical machine.   7. The stator winding according to claim 1, wherein a plurality of conductor segments are used as the electric conductors, and ends of the plurality of conductor segments are joined to each other to form the stator winding. 8. Stator for rotating electric machine.   The stator of the rotating electrical machine according to claim 7, wherein a cross-sectional shape of the conductor segment in the slot is a substantially rectangular shape along the slot shape.   The stator of a rotating electrical machine according to any one of claims 1 to 8, wherein the stator is applied to a rotating electrical machine mounted on a vehicle.

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