JP2000069701A - Wave-wound coil of rotating machine, and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the wave-wound coil of a rotating machine where the reduction of the space of the coil end of a plate-shaped angle crossover conductor type of wave-wound coil and reduction of resistance power loss is possible, and besides which is excellent in its cooling property and is easy of manufacture. SOLUTION: The wave-wound coil of a rotating machine comprises a slot conductor 21 whose coil conductor is made of a conductor in the shape of a thin plate and is inserted in a slot, and a crossover conductor 22 which connects the ends of a pair of slot conductors, and this crossover conductor 22 is made in angle form on the roughly peripheral face, and it is folded up at the tip (top) 22a of this crossover conductor 22 or it is provided with a step, whereby one half of the crossover conductor 22 is displaced by the amount of thickness in its thickness direction as compared with the other half. Furthermore, the crossover conductor 22 on the inside in diameter of the coil end is projected in axial direction of the core more than the crossover conductor 22 on the outside in diameter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wave winding of a rotary electric machine and a method of manufacturing the same.

[0002]

2. Description of the Related Art As a method for winding a stator winding or a rotor winding of a rotating electric machine such as a motor or a generator, a predetermined number of conductors are wound around one magnetic pole, and after the winding is completed, the next magnetic pole is wound. There are known a concentrated winding method and a wave winding method in which a conductor is wound in a wave shape.

[0003]

However, in the case of concentrated winding, since winding is performed for each magnetic pole, it takes a long time to manufacture. Also, in the case of wave winding, when winding a three-phase coil widely used in a rotating electric machine, the winding operation becomes complicated, and it is difficult to use a coil conductor having a large cross-sectional area in the winding operation. Therefore, the resistance power loss of the coil conductor is large, and it is not easy to improve the slot space factor of the coil conductor. Further, there is a problem that the coil end becomes large, the total conductor length increases, and the resistance power loss at the coil end increases.

In order to solve these problems in wave winding, the present inventors formed a coil conductor by a thin plate-shaped conductor, and formed an end of a forward conductor inserted into a slot and an end of a return conductor. The transition conductor portion connecting the first and second portions is formed in a mountain shape on the substantially peripheral surface, and the transition conductor portion is folded or provided with a step at the front end portion (peak portion), thereby forming a half of the transition conductor portion. We have developed a wave winding structure for a rotating electrical machine that has a coil end that is displaced by the thickness in the thickness direction compared to the other half (hereinafter, referred to as a plate-shaped chevron conductor wave winding coil). .

However, in the coil end of the plate-shaped chevron-shaped transition conductor type wave winding coil, there is a problem that heat dissipation is inferior because the transition conductors overlap at a very high density.
Also, the pitch (circumferential width) of the transition conductor portion needs to be reduced as it moves toward the inside of the radius, but such pitch adjustment of the transition conductor portion requires a reduction in the length of the transition conductor portion, and the coil conductor Was complicated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and it is possible to reduce the space at the coil end and the resistance power loss of the above-mentioned plate-shaped chevron-shaped crossover conductor type winding coil, and furthermore, it is excellent in its cooling performance. Further, it is an object of the present invention to provide a wave winding of a rotating electrical machine and a winding method thereof which are easy to make.

[0007]

Since the wave winding of the rotating electric machine of the present invention has the above-mentioned plate-shaped chevron-shaped crossover conductor type wave winding coil structure, the winding is performed only by inserting a preformed coil into the slot. Can be completed, and the winding operation becomes easy. Also, since there is no coil conductor plastic deformation work such as bending during the winding work, a coil conductor having a large cross-sectional area can be used, and the slot space factor of the coil conductor can be improved. Since the total conductor length can be reduced, the resistance power loss of the coil can be reduced.

Further, the required space of the coil end can be remarkably reduced as compared with the conventional wave winding.
Further, in the present configuration, since the axial lengths of the plurality of transition conductors laminated in the radial direction are made different, the exposed surface area of the transition conductor, particularly the transition conductor located at the center in the radial direction (other transition surface areas). The surface area of the portion that does not overlap with the conductor portion) can be increased, and the cooling performance can be improved.

According to a second aspect of the present invention, in the wave winding of the rotating electric machine according to the first aspect, each of the crossover conductors has a bent end formed by bending a thin plate-shaped conductor at an axial end. Since the structure having one piece at a time (bending structure) is adopted, the crossover conductor portion of the plate-shaped chevron crossover-type wave-wound coil can be easily manufactured. Note that, in addition to the bent structure, the transition conductor portion of the plate-shaped chevron transition conductor-type wave-wound coil has a thickness corresponding to the thickness of the transition conductor portion in the radial direction at the axial end portion of the transition conductor portion in the radial direction. A displaceable structure (hereinafter, referred to as a step structure) may be employed.

According to a third aspect of the present invention, in the wave winding of the rotating electric machine according to the first or second aspect, each of the crossover conductor portions has an equal length. By doing so, it is possible to simplify the operation of manufacturing the wave winding, that is, the coil. That is, the pitch of the radially inner transitional conductor portion, that is, the circumferential width Li, of the two transitional conductor portions radially adjacent to each other at the coil end, the thickness of the transitional conductor portion is t,
When the radius of the radially inner transition conductor portion from the core center is r, the pitch of the radially outer transition conductor portion, that is, the circumferential width Lo
Than at the rate of r / (r + t). However, in this configuration, since the lengths of the transition conductors are equal, as a result, the radially inner transitional conductor projects more axially than the radially outer transitional conductor.

In other words, even if each transition conductor is formed at an equal pitch before the slot is inserted, the axial end of the radially inner transitional conductor is more axially moved than the radially outer transitional conductor. By projecting, the pitch of the crossover conductor portion, that is, the circumferential width can be readjusted, and the slot conductor portion can be inserted into the slot without any problem. Therefore, according to this embodiment, in addition to the improvement of the coil end cooling effect described in claim 1, simplification of the manufacturing operation can be realized.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a wave-wound winding having equal-length transition conductors according to the third aspect of the present invention. ,
Also, before inserting each transition conductor into the slot, the pitch of each transition conductor is adjusted by plastic deformation of the transition conductor so that each slot conductor can be adjacent in the slot in the radial direction. In addition, the above-described plate-shaped chevron-shaped conductor-type wave-wound coil can be manufactured.

The pitch adjustment may be performed by plastic deformation or elastic deformation of the crossover conductor. Further, it is possible to adjust the axial end portion of the transition conductor portion on one end side of the slot conductor portion and the axial end portion of the transition conductor portion on the other end side of the slot conductor portion in opposite directions. In addition, in addition to the present configuration, the cross-section may be formed by bending the axial end of the conductor portion at an appropriate angle.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described with reference to the following examples.

[0015]

Embodiment 1 An embodiment of a three-phase motor in which a wave winding of the present invention is applied to a stator winding will be described. FIG. 1 is a plan view of a stator of the motor, FIG. 2 is a front view, FIGS. 3 to 10 show a procedure for forming a stator coil, and FIG. 11 is a cross-over conductor located outside the coil end. 21 and FIG.
Indicates a crossover conductor portion 21 located radially inside the coil end.

Reference numeral 1 denotes a stator core formed by laminating thin plate-shaped electrode steel plates, and has a large number of slots opened on the inner diameter side. In each slot, a star-connected three-phase two-layer wave-wound stator coil (hereinafter, also simply referred to as a coil) 2 is wound. A plate-shaped wedge 4 for preventing protrusion is fitted.
An insulator 3 for insulating the coil 2 and the core 1 from each other is inserted into the inner periphery of the slot.

The coil 2 has a linear slot conductor 21 inserted into the slot, and a transition conductor 22 formed integrally with the slot conductor 21.
Are individually connected to the same ends of a pair of slot conductors 21 inserted into slots on both sides sandwiching two slots. The coil 2 is composed of three phase coils 2a, 2b and 2c as shown in FIG.
As shown in FIG. 3, the starting conductor 21a extending in the traveling direction away from the starting ends 23 to 25 of the phase coils 2a, 2b, 2c, and the starting end 2 of the phase coils 2a, 2b, 2c.
And a return conductor portion 21b extending in the return direction approaching as viewed from 3 to 25. Therefore, the coil end portions 2d on both sides of the slot are, to be precise, composed of the end portions on both sides of the slot conductor portion 21 and the transition conductor portion 22.
As shown in FIG. 1, is bent obliquely in the circumferential direction with respect to the slot conductor 21, is bent at the center of the crossover conductor 22, and has a mountain shape at its axial end.

More specifically, each of the bent ends 22a is overlapped by being radially folded and overlapped at the axial end. Therefore, the folding of the axial end portion 22a of the crossover conductor portion 22 imparts a radial displacement equal to the thickness to the pair of slot conductor portions 21 extending from both ends of the crossover conductor portion 22. The transition conductor 22
Even if the step portion is formed by plastic deformation instead of folding the axial tip portion 22a of the axial direction, a pair of slot conductor portions 21 extending from both ends of the crossover conductor portion 22 are similarly displaced in the radial direction equal to the thickness. Can be given. Since the axial end portion 22a of the crossover conductor portion 22 does not overlap with the adjacent crossover conductor portion 22 in the radial direction, the bending in the radial direction or the provision of a step can be performed without any trouble.

Hereinafter, the coil 2 will be described in more detail. As shown in FIG. 3, the coil 2 has six coil conductors 201 to 201 arranged in parallel at a distance of one slot pitch.
206, and the coil conductors 201 and 204 are the phase coils 2
a, and the coil conductors 203 and 206 are phase coils 2b
And the coil conductors 202 and 205 constitute the phase coil 2c. Each of the coil conductors 201 to 206 has a substantially rectangular cross-sectional shape that is thin in the radial direction of the stator core 1 and wide in the circumferential direction.

The n-th (n is an integer) slot conductor portion of the m-th (m is an integer) coil conductor is the m-th (m is an integer) coil conductor.
The first coil conductor is accommodated in a slot 180 electrical degrees away from the slot in which the (n-1) -th or (n + 1) -th slot conductor portion 21 is accommodated, that is, a slot separated by a 3-slot pitch. In addition, in the slots separated by the pitch of three slots, the (m−3) th or the (m +) th
It is housed together with the slot conductor portion 21 of the third coil conductor.

Further, among the starting ends of the six coil conductors 201 to 206, the second, fourth, and sixth starting ends are short-circuited to each other to be a neutral point, and the remaining first, third, and fifth starting ends are three. Terminals of the phase coils 2a, 2b, 2c connected in a phase star configuration. A specific method for manufacturing the coil conductors 201 to 206 will be described with reference to the manufacturing procedure shown in FIGS.

First, as shown in FIG. 3, six coil conductors 201 to 206 are arranged in parallel at intervals of one slot pitch. The slot conductor portion 21 and the transition conductor portion 22 are each formed in a linear band shape, and the transition conductor portion 22 has an appropriate angle (here, about 60
Degrees). 23 is a coil conductor 201
24 is a starting end of the coil conductor 203;
Reference numeral 25 denotes a start end of the coil conductor 205, 26 denotes a start end of the coil conductor 202, 27 denotes a start end of the coil conductor 204, and 28 denotes a start end of the coil conductor 206.

Next, as shown in FIG.
The first six transition conductors 22 counted from the starting ends 23 to 28 of the first to second 206 are positioned at the center (indicated by a broken line in FIG. 3) so that the first slot conductor 21 is located below (by valley folding). )
Bend. In FIG. 3, each coil conductor 201
The first slot conductor portion 21 and the next slot conductor portion 21 counted from the starting ends 23 to 28 of the first to third slot conductors 206 to 206 are formed at a pitch of three slots apart from each other.
The second slot conductor 21 of the coil conductor 202 overlaps the first slot conductor 21 of the coil conductor 205, and so on. On top of
The second slot conductor 21 of the coil conductor 203 overlaps the first slot conductor 21 of the coil conductor 206.

Next, as shown in FIG.
At the center (shown by a broken line in FIG. 4), the sixth six transition conductors 22 counted from the start ends 23 to 28 of the first to second 206 are shown.
The second slot conductor 21 is folded over the third slot conductor 21 (by mountain fold, that is, in the same rotational direction as the first folding direction). Thereby, the third slot conductor 21 of the coil conductor 201 overlaps with the second slot conductor 21 of the coil conductor 204, and similarly, the third slot conductor 21 of the coil conductor 202 The third slot conductor 21 of the coil conductor 203 overlaps below the second slot conductor 21 of the coil conductor 206. As a result, the third slot conductor 21 is accommodated at the same depth (the deepest position) within the slot as the first slot conductor 21 without difficulty.

Hereinafter, as shown in FIG.
By folding in the same rotation direction as the mountain fold and the valley fold, six coil conductors 201 to 206 are provided in each slot.
Housed in layers. As a result, the coil conductors 201 to 201 are bent by the number of times obtained by subtracting 1 from the number of rotor magnetic poles.
The coil 206 makes one round, and a coil for two turns is formed in two layers in the slot.

Next, as shown in FIG. 7, the sheet is folded in the opposite rotation direction (ie, the last folding of the first two turns is a valley fold, so it is again a valley fold). Thus, the subsequent slot conductor 21 can be smoothly arranged in the third and fourth layers in the slot. Subsequently, as shown in FIG. 8, six coil conductors 201 to 206 are placed in each slot by sequentially bending in the opposite rotation direction to the valley fold, the mountain fold, the valley fold, and the first two turns.
Housed in layers. As a result, each coil conductor 2 is bent again by the number of times obtained by subtracting 1 from the number of rotor magnetic poles.
01 to 206 perform the next round, and coils for four turns are formed in four layers in the slot. Hereinafter, the required number of turns is produced in the same procedure as described above.

Next, after making a predetermined turn, as shown in FIG. 8, the final crossover conductor portion 22b of the coil conductors 201 to 206 has a length approximately half that of the conventional crossover conductor portion 22. Further, the final transition conductor portion 22b of each of the coil conductors 204 to 206 is obliquely arranged in a line symmetrical direction with the other transition conductor portions 22 and the final transition conductor portion 22b. As a result, as shown in FIG. 10, the end portions of the final crossover conductor portions 22b of the coil conductors 201 and 204 overlap, and the coil conductor 2
02 and 205, the leading end portions of the final transition conductor portions 22b overlap, and the final transition conductor portions 22b of the coil conductors 203 and 206 overlap.
Are overlapped, and by welding these overlapping portions, a three-phase stator coil is formed. More specifically, as shown in FIG.
01 to 203, and then the coil conductors 204 to 206 are bent as shown in FIG.
What is necessary is just to form the said overlap and to weld.

Next, the coil 2 manufactured as described above is inserted into each slot of the stator core 1, and before or next to the slot insertion, the starting ends of the coil conductors 202, 204, 206 are short-circuited to neutral points. And FIG. 1 shows a main part of this embodiment.
1, will be described below with reference to FIG. FIG. 11 shows FIG.
As shown in the figure, the slot conductor portion 2 radially adjacent to the five layers
1 and the radially outermost slot conductor portion 21 and the radially outer transitional conductor portion 22, and FIG. 12 shows the radially innermost slotted conductor portion 21 and the radially outer conductor portion 22.

The pitch of the radially inner transition conductor 22 (see FIG. 12), that is, the circumferential width Li, is such that t is the thickness of the transition conductor 22, and r is the radius of the radially inner transition conductor 22 from the center of the core. In this case, the pitch is shorter by r / (r + t) than the pitch of the radially outer transition conductor portion 22, that is, the circumferential width Lo. The circumferential width of the transition conductor 22 can be changed by creating the coil 2 in which the circumferential widths of the transition conductors 22 are all equal in the steps of FIGS. 22 is gripped with a jig and pulled at once in opposite directions to the direction in which the slot conductor portion 21 extends,
Thereby, the angle of the crossover conductor portion 22, that is, the circumferential width thereof may be adjusted to a required value.

As a result, the circumferential width of each transition conductor 22 is equal to the pitch of the slot into which it is inserted, so that the slot conductor 21 can be smoothly inserted into the slot lot. Since the portion 22 protrudes in the axial direction from the radially outer transition conductor portion 22, the tip end of each transition conductor portion 22 is cooled by the cooling air flow better than before.

Note that this pitch adjustment is performed by the transition conductor portion 22.
May be performed by plastic deformation or elastic deformation.
That is, the slot conductor portion 21 may be inserted into the slot while pulling both the crossover conductor portions 22 in the direction in which the slot conductor portion 21 extends with the jig.

[0032]

[Modification] First, a plurality of conductors may be arranged in the circumferential direction to form one coil conductor. In addition, the coil conductors 201 and 2
Reference numeral 06 designates the crossover conductor 22 in advance as the slot conductor 21.
Instead of being inclined, the connecting conductor 22 may be bent at the time of bending.

Further, a coil for even number of turns (a coil group in the present invention) is formed by the six coil conductors 201 to 206, and a coil for even number of turns in the other six coil conductors (in the present invention). Coil group), and these coil groups may be connected to each other by, for example, a method in which the transition conductor portion 22 having a half length is overlapped and welded. The coil conductors 201 and 204, the coil conductors 202 and 205, the coil conductors 203 and 206, and the above-described final crossover conductors may be formed by bending and then coil-formed in order from FIG.

Further, the coil conductors 202, 204, 206
It is also possible to make a delta connection instead of short-circuiting the start end of.

[Brief description of the drawings]

FIG. 1 is a plan view of a stator in an embodiment of a three-phase motor in which a wave winding of the present invention is applied to a stator winding.

FIG. 2 is a front view of the stator shown in FIG.

FIG. 3 is a process diagram showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 4 is a process diagram showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 5 is a process chart showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 6 is a process diagram showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 7 is a process chart showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 8 is a process diagram showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 9 is a process diagram showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 10 is a process diagram showing a procedure for producing the stator coil shown in FIGS. 1 and 2;

FIG. 11 is a development view of the coil 2 showing a slot conductor 21 inserted outside the slot and a crossover conductor 22 extending therefrom.

FIG. 12 is a developed view of the coil 2 showing a slot conductor 21 inserted inside the slot radially and a crossover conductor 22 extending therefrom.

[Explanation of symbols]

1 is a stator core, 2 is a coil, 21 is a slot conductor,
22 is a crossover conductor, 22a is a bent end

Claims (4)

[Claims] 1. A slot conductor portion comprising a forward conductor portion and a return conductor portion alternately inserted into each slot of a core, and the same side of the forward conductor portion and the return conductor portion integrally formed with the slot conductor portion. In a wave winding of a rotating electric machine having a coil conductor composed of a crossover conductor portion connecting end portions, a plurality of thin plate-like conductors each extending from a thin plate-shaped conductor extending in a posture in which a thickness direction is a radial direction of a core. A coil end configured by laminating transition conductor portions in the radial direction, wherein a plurality of the transition conductor portions laminated in the radial direction have different axial lengths; Winding. 2. The wave winding of a rotary electric machine according to claim 1, wherein each of the crossover conductor portions has a bent end portion formed by bending the thin plate-shaped conductor at an axial end portion. Characteristic wave winding of rotating electric machine. 3. The wave winding of a rotating electric machine according to claim 1, wherein each of the crossover conductor portions has an equal length. 4. A method of manufacturing a wave winding of a rotating electric machine according to claim 3, wherein the respective crossover conductor portions that are radially adjacent to each other in the slot are formed at equal pitches, and A rotating electric machine, wherein, before inserting each of the transition conductors into the slot, a circumferential width of the transition conductor is adjusted so that each slot conductor can be radially adjacent to each other within the slot. Method of manufacturing a wave winding.