ROTATING-ELECTRICAL-MACHINE STATOR, AND ROTATING ELECTRICAL MACHINE PROVIDED WITH SAME
1. A stator of a rotating electric machine, comprising:
- a stator core having a plurality of slots;
a stator coil inserted into the plurality of slots, wherein the stator coil includes two or more conductors, whereinthe two or more conductors are arranged such that a gap is generated between adjacent crossing conductors, the gap having a shape of a parallelogram.
A stator of a rotating electric machine includes a stator and a stator coil. The stator core has a plurality of slots. The stator coil is inserted into the plurality of slots. The stator coil includes two or more conductors. The two or more conductors are arranged such that a gap is generated between adjacent crossing conductors, the gap having a shape of a parallelogram.
- 1. A stator of a rotating electric machine, comprising:
a stator core having a plurality of slots; a stator coil inserted into the plurality of slots, wherein the stator coil includes two or more conductors, wherein the two or more conductors are arranged such that a gap is generated between adjacent crossing conductors, the gap having a shape of a parallelogram.
- View Dependent Claims (2, 3, 4)
This application is a continuation of U.S. application Ser. No. 15/320,943, filed Dec. 21, 2016, which is a 371 of International Application No. PCT/JP2015/071439, filed Jul. 29, 2015, which claims priority from Japanese Patent Application No. 2014-160935, filed Aug. 7, 2014, the disclosures of which are expressly incorporated by reference herein.
The present invention relates to a stator of a rotating electric machine such as a motor and a generator, and a rotating electric machine including the stator.
JP 2011-234482 A (PTL 1) discloses a background art of the present technical field. The publication discloses that “there is provided a stator of a rotating electric machine that can reduce damage to an insulation film of a conductor that forms a stator coil while suppressing enlargement of a coil end of the stator coil. A turn portion of the conductor is formed of a protruding portion that protrudes from a first slot in a direction parallel to an axial direction of a stator core, a slope portion that diagonally extends at an angle of less than 90 degrees toward a kth slot (another slot), which is separated from the first slot at a predetermined interval (one magnetic pole pitch) via a first bent portion bent in a circumferential direction from a tip of the protruding portion, and a second bent portion bent in a direction parallel to the axial direction of the stator core from a tip of the slope portion, and connected to a slot housing portion housed in the kth slot. Therefore, the turn portion includes two bent portions, and is formed in an asymmetric shape in a circumferential direction.
- PTL 1: JP 2011-234482 A
However, in the technique disclosed in PTL 1, enlargement of a wire diameter of a stator coil causes coils adjacent to each other to easily interfere therewith when shifting from a first slot to a second slot. In order to avoid the interference therebetween, many parts of a conductor need to be bent at the time of slot shift; however, the risk of damaging an insulation film that covers a coil surface increases. Making the insulation film thick as a countermeasure against the above causes a problem of decreasing a space factor of the conductor in the slot and thus, lowering the efficiency. In addition, it becomes difficult to reduce the height of the coil end due to the interference between the adjacent conductors.
Accordingly, an object of the present invention is to provide a stator of a rotating electric machine in which the height of a coil end of a stator coil is reduced while interference between adjacent conductors at the coil end is avoided, and to provide a rotating electric machine including the stator.
In order to solve the problem described above, configurations described in claims are adopted, for example.
The present application includes a plurality of methods to solve the problem described above. An example of such methods is a stator of a rotating electric machine, including a stator core that has a plurality of slots, and a stator coil inserted into the slot. In addition, the stator coil includes two or more conductors disposed in the same layer as a first conductor and inserted into the slots adjacent to the first conductor, and a shape of a coil-protruding portion protruding to an outer diameter is an arc-like shape.
The present invention can provide a stator of a rotating electric machine in which the height of a coil end of a stator coil is reduced while interference between adjacent conductors at the coil end is avoided, and a rotating electric machine including the stator.
Other problems, structures, and effects that are not described above will be apparent from the following description of the embodiment.
Hereinafter, an embodiment of the present invention will be described.
In the following description, a rotating electric machine for a hybrid electric vehicle is used as an example of a rotating electric machine. In addition, in the following description, an “axial direction” refers to a direction along a rotation axis of the rotating electric machine. A circumferential direction refers to a direction along a rotation direction of the rotating electric machine. A “radial direction” refers to a radius vector direction (radial direction) when the rotation axis of the rotating electric machine is regarded as a center. An “inner periphery side” refers to an inner side (inner diameter side) in the radial direction, and an “outer periphery side” refers to the opposite direction, that is, an outer side (outer diameter side) in the radial direction.
First, an outline of the embodiment will be described.
The embodiment described herein relates to a coil structure of the stator of the rotating electric machine. The rotating electric machine mainly includes a cylindrical stator, and a rotor disposed on an inner periphery side of the stator at a predetermined distance from the stator.
The stator has a plurality of magnetic poles arranged such that the polarity alternates in a rotation direction, and includes a cylindrical stator core, and a plurality of stator coils wound around the stator core. The stator core includes a plurality of slots that are formed to penetrate the stator core in the axial direction and arranged circumferentially to accommodate the stator coils. Each stator coil is formed by electrically connecting a number of conductors disposed in the respective slots. The coil extends axially in the slot, while a lead-out line portion led out from one axial end of the slot extends over multiple slots arranged at predetermined circumferential pitches to correspond to the plurality of magnetic poles. The stator coils each include a crank portion that shifts in layer as the coils are separated from each other at predetermined circumferential pitches. The stator coils are configured such that the coils led out from the adjacent slots do not interfere with each other.
In the present embodiment, there is also provided a bent portion that is bent back from the outer side in the radial direction toward the inner side in the radial direction, in addition to the crank portion for layer shift in the plurality of phases of stator coils. The bent portion that is bent back can increase the distance for avoiding interference between the adjacent coils, thus decreasing the axial height of the coils. Therefore, it is possible to reduce the height of the coil ends, and to secure a gap from other devices such as a mission portion.
Next, the embodiment will be described in detail with reference to the drawings.
Rotating torque generated by the engine 2 and the rotating electric machine 3 is transmitted to wheels (driving wheels) 6 via a transmission 4, such as a stepless transmission or a stepped automatic transmission, and a differential gear 5. The rotating electric machine 3 is installed between the engine 2 and the transmission 4, or in the transmission 4. Thus, the rotating electric machine 3 needs to have a small size and a high output in order to minimize an influence of space on the vehicle 1.
The rotating electric machine 3 includes a stator 100 and a rotor 200. The rotor 200 is disposed on the inner periphery side of the stator 100 via a gap 11. The rotor 200 is fixed to the shaft 201 and rotates integrally with the shaft 201. Both ends of the shaft 201 are rotatably supported by the case 7 by bearings 202A and 202B. The outer periphery side of the stator 100 is fixed on the inner periphery side of the case 7 with a bolt 12 or the like. The rotating electric machine 3 is a three-phase synchronous electric motor using a permanent magnet as the rotor 200, and functions as an electric motor when a large three-phase alternate current (e.g., about 300 A) is supplied to the stator 100.
As illustrated in
Each stator coil 102 includes a number of conductors 106 that are inserted into and held in the slots 105, as will be described later. The conductors 106, which are provided adjacent to each other in the same slot 105, are welded together at a welding portion 104 formed at one axial end side (lower end side of
Each stator coil 102 extends over multiple slots 105 arranged apart from each other at predetermined circumferential pitches, by a substantially U-shaped or V-shaped lead-out line portion 107 that is led out from one axial end of the slot 105. The plurality of stator coils 102 generates a plurality of magnetic poles whose polarity alternates in the rotation direction.
As illustrated in
In the present embodiment illustrated in
Each conductor 106 that constitutes the stator coil 102, as illustrated in
A segment coil may also be used as the conductor 106. In this case, before the segment coil is inserted into the slot 104, it is possible to form, in advance, coil ends located at both axial ends that are further outside from the ends of the stator core 101, and to easily provide an appropriate insulating distance between different phases or identical phases.
When the stator 100 is viewed from the axial direction, the conductor 106 is disposed on a circumference having a predetermined radius R. As illustrated in
As illustrated in
As illustrated in
Consequently, while minimizing the protrusion of the coil end portion in the outer diameter direction of the stator core, it is possible to avoid the interference between the adjacent stator coils, which in turn can reduce the height of the coil ends regardless of the wire diameter.
As described above, according to the present invention, the bent portions which are provided in the axial direction in the segment coil in the stator of the rotating electric machine for a vehicle include one at the vertex and two at slot root portions. At the same time, the bent portions include the first bent portion that is provided and bent in the outer diameter direction of the stator core, and the second or more bent portions that are bent back from the outer diameter direction to the inner diameter direction. With this configuration, it is possible to minimize the protrusion of the coil end portion in the outer diameter direction of the core and to avoid the interference between the adjacent coils. Therefore, it is possible to provide a stator structure of the rotating electric machine, in which the height of the coil ends can be reduced regardless of the wire diameter.
The present invention is not limited to the above-mentioned examples, and includes a variety of modifications. For example, the examples described above have been described in detail in order to describe the present invention for easy understanding, and are not necessarily limited to those including all the configurations described above. In addition, some configurations in the examples can be deleted or replaced by another configuration, or another configuration can be added thereto.
- 1 vehicle
- 2 engine
- 3 rotating electric machine
- 4 transmission
- 5 differential gear
- 6 wheel
- 7 case
- 100 stator
- 101 stator core
- 102 stator coil
- 103 insulating paper
- 104 welding portion of conductor
- 105 slot
- 106, 106a-d conductor
- 107 U-shaped or V-shaped conductor lead-out portion
- 108 slit portion provided in slot
- 109 crank portion
- 110 linear portion of conductor in slot
- 111 gap generated between crossing conductors
- 112 flat shape of coil end outer diameter
- 200 rotor
- 201 shaft
- 202A, 202B bearing
- 300 coil-end conductor portion
- 301 inclined portion
- 302 bent portion between inclined portion and linear portion of conductor
- 303 crank portion for layer shift of stator coil
- 304 connection angle of bent portion between inclined portion and linear portion of conductor
- 305 radially bent portion provided in inclined portion