CN101515733B - Rotating machine, continuous winding coil, distributed winding stator and method for forming same - Google Patents

Abstract

The present invention relates to a rotating electrical machine, a crank-shaped continuously wound coil, a distributed winding stator, and methods for their manufacture. An object of the present invention is to obtain a small-sized and high-output rotating electrical machine in which the coil ends are smaller than conventional ones and the current density is reduced in a distributed winding stator using rectangular conductors for the coils. Conductor wires with a rectangular cross-section are overlapped and wound, and the tops of both ends are shifted only by the full width of the overlapped wires, and a crank shape is formed with a length within the interval between adjacent slots, and inserted into the stator. formed in the groove.

Description

Rotating electric machine, continuous winding coil, distributed winding stator and method of forming same

technical field

The present invention relates to a rotating electric machine such as a motor or an engine, a crank-shaped continuous winding coil, a distributed winding stator, and methods for forming them.

Background technique

The winding method of the stator includes concentrated winding in which coils are wound on each magnetic pole tooth in a concentrated manner, and distributed winding in which coils are wound across a plurality of slots and coils of different phases or same phases are overlapped at the ends of the coils. A stator with concentrated windings can reduce the size of the coil ends, which is effective in reducing the size and efficiency of rotating electrical machines. On the other hand, the stator with distributed winding can make the rotating magnetic field in the inner circumference of the stator close to a sine wave, which has higher output power than concentrated winding and can reduce noise. In addition, the two are used together, and as a method of achieving high output, the copper wire with the coil is used with a rectangular cross-section wire, thereby increasing the space factor of the coil in the stator slot. The present invention is aimed at a rotating electrical machine having distributed windings in which stator coils are formed of wires having a rectangular cross section.

Patent Document 1 (Japanese Unexamined Patent Application Publication No. 4-168955) discloses a technical solution in which a flat-angled rectangular conductor is bent and formed so that the long-side surface faces the radial surface of the stator slot, and it is formed from the The axial end surface of the stator core is inserted into the slot, and the open ends of the rectangular conductor pieces protruding from the opposite end surface of the stator core are electrically connected to form a circuit structure of the wave winding. This rectangular conductor has a substantially U-shape, and the surfaces on the short sides of the rectangular cross-section are in the same direction.

In addition, Patent Document 2 (Japanese Unexamined Patent Application Publication No. 6-284651) describes a technique in which four rectangular conductors having the same vertical and horizontal dimensions are bundled and used. The bundled four conductors have a substantially loose leaf shape, and the surfaces of the conductors facing the radial surfaces of the grooves are in the same direction.

In addition, in Patent Document 3 (Japanese Patent Application Laid-Open No. 8-298756 ), it is described that a coil called a "form-wound coil" used in a medium-to-large rotating electrical machine will have a self-adhesive layer. The flat wire is wound into an ellipse, and the coil end is twisted and deformed after the whole is solidified to generate a non-interfering shape of the coil end. The conductors constituting the coil are arranged in the same direction in the slot and at the end of the coil, and are in a state of fastening and close contact with each other.

Also, in Patent Document 4 (Japanese Unexamined Patent Application Publication No. 10-66314), a distributed winding coil system is described in which a rectangular wire is wound multiple times to form a coil-shaped coil and is inserted into a slot so as to straddle a predetermined slot. stator winding.

In these existing technologies, in the distributed winding stator, the windings of flat-angled rectangular conductors are used. The wire has a structure in which the tip of the conductor forming the coil end protrudes.

The problem to be solved by the present invention is to invent the shape of the coils and the forming method thereof for obtaining a high-power rotating electric machine that realizes high output, miniaturization, and high efficiency in a distributed winding stator.

With regard to higher output, since the output of a rotating electrical machine is roughly determined by the number and shape of the slots of the stator core and the occupied area of the conductors in the slots, a high space factor of the conductors in the slots is a problem.

With regard to miniaturization, since the size of the distributed winding stator is fixed since the size of the stator core is fixed, reducing the coil end portions at both ends of the stator core is an issue for miniaturization of the rotating electric machine. The conductor disclosed in Patent Document 2 is a segmented coil (split coil) type in which four are bundled. Four rectangular conductors serving as coil wires are roughly bent into a loose leaf shape and opened back and forth with the top of the bent head as a fulcrum. The height of the portion corresponding to the full width of the bundled conductors is the minimum required. In addition, the conductor disclosed in Patent Document 3 is an elliptical form-wound coil type in which rectangular wires are overlapped and wound. Since the conductors at both ends of the bend are used as fulcrums to open back and forth, the height of the part corresponding to the long sides of the rectangular wires becomes the minimum required. Re-examining the bending and forming method of these conductors, and obtaining a molded coil type with a lowered crown became a subject.

As for high efficiency, reduction of current density and reduction of copper loss are mentioned. The conductor disclosed in Patent Document 1 is a segmented coil type in which a rectangular wire is bent into an approximately U-shape, and has a structure in which two conductors are radially arranged in one slot. It is a problem to reduce the current density by making the conductor arranged in the groove finely divided in the radial direction.

In addition, the conductor disclosed in Patent Document 2 has a structure in which four end wires on one side are connected by welding or the like because four segment coils are bundled. It is an issue to realize reduction of copper loss by reducing the number of connection points.

Contents of the invention

In order to solve the three problems described above, the shape of the coil and its forming method are important, and the object of the present invention is to obtain a shape of the coil and a forming method thereof for obtaining high output and realizing compactness in a distributed winding stator. High-efficiency rotating electrical machines.

The rotating electric machine of the present invention is provided with a multi-phase stator winding in which a rectangular conductive wire with an insulating protective film is wound multiple times to form a helical winding coil and is housed in a slot of a stator core. The coil is formed with crank-shaped portions substantially at the tops of both ends without twisting.

According to the present invention, in a stator using a distributed winding in which coils of conductors having a rectangular cross-section are overlapped and wound, the coil ends are smaller than conventional ones, and the conductors are radially divided in the slots. Thereby, the advantages of the distributed winding stator having excellent rotation characteristics can be effectively utilized, and a high-output rotating electric machine can be downsized and efficient.

Description of drawings

FIG. 1 is an explanatory diagram of a form-wound coil according to Example 1 of the present invention.

Fig. 2 is an explanatory diagram of a distributed winding stator according to Embodiment 1 of the present invention.

Fig. 3 is an explanatory diagram of a continuous winding step in the molding process of the form-wound coil according to Example 1 of the present invention.

Fig. 4 is a perspective view of a wire-wound coil and a form-wound coil in the molding process of Example 1 of the present invention.

Fig. 5 is an explanatory diagram of the deformation process from the forming of the wire-wound coil to the form-wound coil in Embodiment 1 of the present invention.

6 is a perspective view of a state where the form-wound coil according to Example 1 of the present invention is installed in a slot of a stator.

7 is a perspective view of a state where the form-wound coil according to Example 1 of the present invention is installed in a slot of a stator.

Fig. 8 is an explanatory view showing the shape of the form-wound coil inserted into the slot of the stator according to the first embodiment of the present invention.

9 is a plan view of a state in which the form-wound coil according to Example 1 of the present invention is installed in a slot of a stator, as seen from the terminal portion side.

Fig. 10 is a perspective view of a state where the form-wound coil according to Example 1 of the present invention is incorporated into a stator and terminal portions are connected.

Fig. 11 is a plan view of the distributed winding stator according to Embodiment 1 of the present invention seen from the end portion side.

Fig. 12 is a cross-sectional view in a slot of a distributed winding stator according to Embodiment 2 of the present invention.

In the picture:

1-angular line, 2-stator core, 3-stator slot, 4-winding coil, 5-form winding coil, 6-insulation sheet, 7-leading part, 8-distributed winding stator, 11-end part, 12- Head top, 13-terminal part side head top, 30-spool, 31-the tapered part of spool, 32-lower die, 33a, 33b-side die, 34a, 34b-upper die.

Detailed ways

Embodiments of the present invention will be described below using the drawings.

Example 1

FIG. 1 shows the structure of a form-wound coil type according to Embodiment 1 of the present invention. Fig. 1(A) is a perspective view before the form-wound coil 5 is installed into the stator core 2, and the stator core 2 is cut and shown. FIG. 1(B) is a perspective view showing a state in which the form-wound coil 5 is incorporated into the stator core 2, and the outline of the stator core 2 is shown by a solid line and a two-dot chain line. The coil wire 1 is a copper corner wire covered with an enamel resin film. The stator core 2 is formed by press-cutting rolled steel plates with a thickness of about 1 mm and laminating them. Continuously wind the coil wire material 1 (three turns in the figure) of the corner wire with the same or similar length on both sides, and overlap the wound coil wire material 1 on the surface along the layer direction, that is, the top portion 12 and the coil end side. The top portion 13 is bent into a crank shape to form a die-wound coil. The form-wound coil 5 is inserted into the stator slot 3 from the inside of the stator core 2 .

FIG. 2 shows a state in which the molded coil 5 according to the first embodiment of the present invention is incorporated into the stator core 2 . The rotating electrical machine of the present invention has three-phase coils of U-phase, V-phase, and W-phase, and includes 24 form-wound coils 5 for each phase, that is, 72 in total, and a stator core 2 with 72 slots corresponding thereto. FIG. 2(A) is a plan view of the distributed winding stator 8 seen from the top portion 12 side in a state where the form-wound coil 5 is housed in the stator core 2 . The form-wound coils 5 are not limited to the insertion positions of the slots, and all have the same shape. In order to accommodate all the form-wound coils 5, the head 2 has a crank shape. In the description of Fig. 10 and Fig. 11, it will be described that the ends of the coil wires 1 are connected by welding to the ends of the coil wires 1 in the same phase to form three-phase coils of U phase, V phase and W phase, and obtain a distributed winding stator 8.

FIG. 2(B) is a partially enlarged cross-sectional view of the stator slot 3 in a state where the form-wound coil 5 is incorporated in the stator core 2 . If the total cross-sectional area of the coil wires 1 in the stator slot 3 is the same, the larger the number, the higher the magnetic flux density. In the present invention, the coil wire 1 is a square wire, and has a structure in which two sets of three coils are axially arranged in the stator slot 3 of the stator core 2, and a structure in which six square conductors are axially arranged in one slot. Therefore, compared with arranging two rectangular conductors axially in one slot, arranging six rectangular conductors can increase the magnetic flux density, reduce the current density, and improve the efficiency as a rotating electrical machine.

The forming method of the form-wound coil of the present invention will be described using FIGS. 3 to 5 .

Fig. 3 shows the process of continuously winding the corner wire 1 by the winding machine. FIG. 3(A) is a perspective view showing a state in which the corner wire 1 is fixed to the bobbin. FIG. 3(B) is a perspective view showing a state in which the corner wire 1 is wound around the bobbin 30 . FIG. 3(C) is a perspective view showing the wound coil 4 detached from the bobbin 30 .

First, as shown in FIG. 3(A), the corner wire 1 is fixed on a bobbin 30 having a tapered portion 31 with a predetermined taper. Then, as shown in FIG. 3(B), the diagonal wire 1 is wound around the bobbin 30 while giving tension to the diagonal wire 1, so that the diagonal wire 1 is wound on the bobbin 30. After winding the predetermined number of turns (3 turns in the present invention), The continuously wound corner wire 1 is detached from the bobbin 30 to obtain a wound coil 4 that replicates the taper of the tapered portion 31 of the bobbin as shown in FIG. 3(C).

In the present invention, the taper required for the die-wound coil 5 is formed at the stage of winding the coil 4 . The number of slots in the stator core of the present invention is 72, and there are 7 slots for putting a form-wound coil. Accordingly, the angle at which the form-wound coil enters the slot is 35 degrees, which is 7/72 of 360 degrees. Therefore, the taper of the tapered portion 31 of the bobbin 30 is 17.5 degrees, half of the angle obtained above. When the taper is large, compressive stress is applied to the wire material on the outer peripheral side of the core of the form-wound coil, and tensile stress is applied to the wire material on the inner peripheral side of the core. In addition, when the taper is small, tensile stress is applied to the wire material on the outer peripheral side of the core of the form-wound coil, and compressive stress is applied to the wire material on the inner peripheral side of the core. When compressive stress is added to the wire rod, buckling deformation occurs in order to alleviate it, and the size of the form-wound coil may increase. On the other hand, when tensile stress is applied to the wire rod, since there is no stress relaxation due to deformation, tensile stress is always added to the wire rod. Therefore, depending on the long-term operating environment of the rotating electrical machine, the wire rod may be broken. The taper of the tapered portion 31 in Embodiment 1 of the present invention preferably ranges from 15 degrees to 20 degrees.

FIG. 4 is a comparison diagram of the schematic shapes of the wound coil 4 and the form-wound coil 5 formed to be inserted into the slot of the stator. The form-wound coil 5 is formed into a shape to be incorporated into the stator core 2 as shown in FIG. 2(A). For this purpose, the crown 12 and the terminal-side crown 13 need to be bent into a crank shape on the surface of the coil wire 1 along the layer direction to form the die-wound coil 5 .

FIG. 5 is a plan view showing the mold and the wound coil 4 or the form-wound coil 5 from the top 12 side, showing the deformation process from the forming of the wound coil 4 to the form-wound coil 5 . Fig. 5 (A) shows the state that winding coil 4 is fixed on the lower mold 32, Fig. 5 (B) shows the state in the middle of descending side mold 33a, 33b, upper mold 34a, 34b, Fig. 5 (C) shows the side The dies 33a, 33b, and the upper dies 34a, 34b are lowered to predetermined positions.

The lower mold 32, the side molds 33a, 33b, and the upper molds 34a, 34b are superhard molds made of steel and whose hardness has been improved through quenching and tempering treatment. Mirror finish is applied to the surface. 5(A) to 5(C), after the wound coil 4 is fixed on the lower mold 32, the side molds 33a, 33b, and the upper molds 34a, 34b are lowered to a predetermined position to form the molded coil 5.

FIG. 6 is a perspective view showing a state where the form-wound coil 5 is installed in the stator slot of the stator core 2 . For convenience of description, the case where the number of form-wound coils 5 is nine is shown. First, the straight portion of the form-wound coil 5 corresponding to the position inserted into the stator slot of the stator core 2 is covered with the insulating sheet 6 . Covering with the insulating sheet 6 serves both as an insulation measure against pinholes in the enamelled protective film covering the coil wire 1 and to prevent damage to the enamelled protective film when the stator core is incorporated.

Then, the form-wound coil 5 to which the insulating sheet 6 is attached is sequentially inserted from the inside of the stator core 20 into the stator slot.

FIG. 7 shows a plan view from the top 12 side of a state where the form-wound coil 5 is inserted into the stator slot 3 of the stator core 2 . For convenience of explanation, the case where the number of form-wound coils 5 is nine is shown. The rotating electric machine of the present invention is a three-phase coil, and is composed of U-phase, V-phase, and W-phase coils. The distribution of symbols U, V, and W shown in the figure indicates U phase, V phase, and W phase, and consecutive numerals indicate the numbers of the form-wound coils 5 assigned to the respective phases. Form-wound coils 5 of the same shape are arranged in the order of U1 , V1 , W1 , U2 , V2 , W2 . . . and incorporated into stator core 2 . The actual number of form-wound coils 5 in the present invention is 24 for each phase, 72 in total, and 72 form-wound coils 5 are installed in the stator core 2 as shown in FIG. 2(A).

FIG. 8 is a plan view of a state in which three form-wound coils are installed in the stator slot 3 of the stator core 2 as seen from the top portion 12 side. For convenience of explanation, only the position of the form-wound coil 5 in the middle is shown in section in the stator slot 3 . In addition, the stator core 2 is indicated by a dashed-two dotted line. The head portion 12 is formed in a crank shape within the interval B2 between adjacent stator slots 3 so as to be offset by the width dimension B1 of the form-wound coil 5 . As a result, form-wound coils 5 of the same shape are inserted into the respective stator slots 3 of the stator core 2 .

If the offset is larger than the width dimension B1 and the form-wound coil 5 is formed, the overall dimension B3 of the form-wound coil 5 becomes large, and the form-wound coil 5 cannot enter the predetermined stator slot 3 . Furthermore, if the form-wound coil 5 is molded with an offset smaller than the width dimension B1, the overall dimension B3 of the form-wound coil 5 becomes small, and this also prevents the form-wound coil 5 from entering the predetermined stator slot 3. On the other hand, when the head portion 12 of the form-wound coil 5 is formed into a crank shape outside the interval B2 of the stator slot 3 , the plurality of form-wound coils 5 contact each other and cannot enter the stator slot 3 .

FIG. 9 is a plan view of a state in which the form-wound coil 5 is inserted into the stator slot 3 of the stator core 2, as viewed from the top end 13 side of the terminal portion. For convenience of explanation, the case where the number of form-wound coils 5 is nine is shown. The end portion 11 indicates the numbers of the form-wound coils 5 assigned in FIG. 7 to the U-phase, V-phase, and W-phase. The end portion 11 is connected to U1 and U3 in the same stator slot, V1 and V3 are adjacently arranged in adjacent stator slots, and W1 and W3 are adjacently arranged in adjacent stator slots. In this way, the form-wound coils 5 of the same phase are incorporated into the same slot.

FIG. 10 is a perspective view showing a state where the form-wound coil 5 is incorporated into the stator core 2 and the end portion 11 is connected. For convenience of description, the case where the number of form-wound coils 5 is nine is shown. In addition, the numbers of the form-wound coils 5 allocated in FIG. 7 to each of the U phase, the V phase, and the W phase are indicated on the terminal portion 11 . U1 and U3 of the end portion 11 are connected by welding to form a continuous U-phase coil. Furthermore, V1 and V3 are also connected by welding to form a continuous V-phase coil. Furthermore, W1 and W3 are also connected by welding to form a continuous W-phase coil.

FIG. 11 is a plan view of a state in which the form-wound coil 5 is incorporated into the stator core 2 and the end portion 11 is connected, as seen from the end portion 11 side. Form-wound coil 5 numbers assigned from 1 to 24 are marked only for phase U. Furthermore, the numbers of the form-wound coils 5 allocated to 1 and 23 are given for the V phase and the W phase. U1 and U3 of the end portion 11 are connected by welding to form a continuous U-phase coil.

U1 and U3 of the terminal part 11 are connected by welding, and then U2 and U4, U3 and U5 are wound in sequence until U23 and U1, U24 and U2 are connected by welding to form a continuous U-phase coil. Although not shown, the V phase and the W phase are similarly wound and connected by welding. In addition, the lead wire 7 made of copper is connected to U23 of the terminal part 11 by soldering. Furthermore, lead wires 7 are also connected to V23 and W23 by welding to obtain a distributed winding stator 8 in which lead wires 7 are distributedly connected to U phase, V phase, and W phase.

Example 2

12 is a partial cross-sectional view of the stator slot 3 in a state where form-wound coils are formed from corner wires 1 coated with thermal adhesive 14 and incorporated into the stator core 2 according to Embodiment 2 of the present invention. Two corner wires 1 are bonded together to form roughly one corner wire, and form-wound coils are formed. The thermal adhesive 14 is melted by heating at a predetermined temperature. Two angled wires 1 are superimposed, and bonding can be performed by applying heating and cooling. This results in a structure in which twelve corner wires 1 are arranged in one groove. Therefore, the magnetic flux density is further increased, the current density is reduced, and the efficiency as a rotating electrical machine can be improved.

Claims (5)

1. electric rotating machine possesses the rectangular conductor with insulating protective film and reels and form repeatedly that spiral helicine coiled wire-wound coil is contained in the groove of stator core and the multi phase stator coiling that constitutes is characterized in that,

Above-mentioned coiled wire-wound coil is to be that the two sides of the overlapping lead corresponding with rectangular shape of the above-mentioned rectangular conductor of rectangular shape and reeling repeatedly form with the cross section with insulating protective film; On above-mentioned overlapping side, be vertically formed the wide format of the width dimensions corresponding with a plurality of leads; And; Possess the roughly head at the two ends of above-mentioned coiled wire-wound coil, distortion ground is along only squint position and the crank shape that forms of width dimensions of wide format of above-mentioned wide format

Above-mentioned crank shape portion crosses over above-mentioned groove and is configured; And a side of the wide format that forms abreast along the wide format deviation post is configured in the inboard of stator slot; The opposing party of the wide format that forms abreast is configured in the entrance side of stator slot; Be inserted into the terminal part at two ends of the coil that prolongs abreast of the different coiled wire-wound coil in the different stator, and the inboard of stator slot and the middle body between the entrance side near and dispose.

2. electric rotating machine according to claim 1 is characterized in that,

The crank shape portion of above-mentioned coiled wire-wound coil is formed on the face of edgewise of the above-mentioned rectangular conductor that constitutes this coiled wire-wound coil.

3. electric rotating machine according to claim 1 is characterized in that,

The crank shape portion of above-mentioned coiled wire-wound coil forms in than the also little scope in the interval of the groove that is formed at the adjacency on the stator.

4. the distributed winding stator of an electric rotating machine is characterized in that,

The continuous winding coil of crank shape; Possess: the cross section with insulating protective film is the two sides of the overlapping lead corresponding with rectangular shape of the lead of rectangular shape and reels repeatedly; On above-mentioned overlapping side, be vertically formed the wide format of the width dimensions corresponding with a plurality of leads, and the coiled wire-wound coil that forms abreast of the part of above-mentioned wide format;

On the direction identical of the both sides of above-mentioned coiled wire-wound coil with the parallel direction of wide format, the terminal part at the two ends of the above-mentioned coiled wire-wound coil that on straight line, prolongs abreast; And,

Roughly head at the two ends of above-mentioned coiled wire-wound coil, distortion ground is along only squint position and the crank shape that forms of width dimensions of wide format of wide format,

Form above-mentioned crank shape through distortion ground not along only the squint position of width dimensions of wide format of wide format; The terminal part at above-mentioned two ends be configured to because of the offset of above-mentioned crank shape approaching on Width; Insert under the state in a plurality of stator slots of stator core of electric rotating machine at the continuous winding coil of above-mentioned crank shape

The crank shape of above-mentioned continuous winding coil is crossed over the said stator groove and is configured; And be configured in the inboard of stator slot along only a squint side of the wide format that the position of width of wide format forms abreast of wide format; The opposing party of the wide format that forms abreast is configured in the entrance side of stator slot; Be inserted into the above-mentioned terminal part at the two ends of the coil of prolongation abreast of the different coiled wire-wound coil in the different stator; And the inboard of stator slot and the middle body between the entrance side near and dispose, and be electrically connected.

5. the formation method of the distributed winding stator of an electric rotating machine is characterized in that,

The continuous winding coil of crank shape possesses: the cross section that will have insulating protective film is the lead of rectangular shape; Also reel repeatedly in the two sides of the overlapping lead corresponding with rectangular shape; On above-mentioned overlapping side, be vertically formed the wide format of the width dimensions corresponding with a plurality of leads, and the coiled wire-wound coil that forms abreast of the part of above-mentioned wide format;

On the direction identical of the both sides of above-mentioned coiled wire-wound coil with the parallel direction of wide format, the terminal part at the two ends of the above-mentioned coiled wire-wound coil that on straight line, prolongs abreast; And,

Roughly head at the two ends of above-mentioned coiled wire-wound coil, distortion ground is along only squint position and the crank shape that forms of width dimensions of wide format of wide format,

Form above-mentioned crank shape through distortion ground not along only the squint position of width dimensions of wide format of wide format, the terminal part at above-mentioned two ends be configured to because of the offset of above-mentioned crank shape approaching on Width,

This method comprises: the continuous winding coil of above-mentioned crank shape is inserted into the operation a plurality of stator slots from the inboard of stator core;

The crank shape of above-mentioned continuous winding coil is crossed over the said stator groove and is configured; And will be configured in the inboard of stator slot along only a squint side of the wide format that the position of width of wide format forms abreast of wide format; The opposing party of the wide format that forms abreast is configured in the entrance side of stator slot; With the terminal part at the two ends of the above-mentioned coil that prolongs abreast that is inserted into different coiled wire-wound coil in the different stator, and the inboard of stator slot and the middle body between the entrance side near and the operation of configuration; And,

Will with the inboard of said stator groove and the middle body between the entrance side near and operation that a plurality of terminal parts of configuration are electrically connected through welding.

Images