CN115001182A - A double-layer flat wire winding structure of a motor - Google Patents

Abstract

The invention relates to a double-layer flat wire winding structure of a motor, which comprises a stator core and three-phase flat wire windings arranged in the stator core, wherein insulation paper is arranged between the stator core and the flat wire windings, the stator core is provided with Z wire slots, the number of slots of each pole of the stator core is q, i flat conductors are embedded in each slot of the stator core, each phase of the windings comprises a plurality of parallel branches, each parallel branch is formed by connecting a plurality of hairpin flat conductors in series, each hairpin flat conductor is provided with an input edge and an output edge, the hairpin flat conductors are sequentially embedded into the stator core at equal pitches, short-distance windings are formed by twisting welding ends, each parallel branch is completely and symmetrically distributed on a magnetic circuit, and the double-layer windings are formed by embedding all the input edges and the output edges of each parallel branch together on different layers in the same number, all the parallel branches are completely symmetrical on a magnetic circuit, and the back electromotive force, the resistance and the inductance are balanced, so that the loop current is eliminated.

Description

A double-layer flat wire winding structure of a motor

technical field

The invention relates to the technical field of flat wire motors, in particular to a double-layer flat wire winding structure of a motor.

Background technique

At present, the manufacture of the stator winding of the flat wire motor is relatively complicated, and due to the limitation of the process, the magnetic circuit of the flat wire winding has the problem of loop current. To solve the problem of winding circulating current, a reasonable winding space distribution design is required to balance the positions of the conductors connected to each branch to achieve the balance of resistance and inductance. The higher the motor frequency, the more urgent the need for transposition, the more conductors per slot and the number of parallel branches, and the more complex the loop design.

The peak speed of new energy motors, especially drive motors, generally exceeds 10,000 rpm. High-speed motors have higher NVH requirements. Round wire motors usually use double-layer short-distance windings, which can effectively reduce the harmonics on the stator side and optimize the NVH performance of the motor. By rationally designing the flat wire winding structure, the harmonics on the stator side can also be effectively reduced.

It is difficult to adjust the number of conductors per slot of the stator winding of the existing flat wire motor. Generally, the number of turns is adjusted by adjusting the number of parallel branches. The Chinese patent application with publication number CN111200328A discloses a 4-way parallel winding structure that does not generate loop current. , but the winding is a single-layer winding with a full pitch, the harmonic content on the stator side is large, and each slot is a same-phase winding, and the loss caused by the AC resistance is large.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a double-layer flat wire winding structure for a motor in view of the corresponding deficiencies of the prior art. The input side and the output side are co-embedded on different layers in the same number, forming a double-layer winding, so that each parallel branch is completely symmetrical on the magnetic circuit, and the back EMF, resistance and inductance are balanced, thereby eliminating the loop current.

The purpose of the present invention is achieved by adopting the following solutions: A double-layer flat wire winding structure of a motor, comprising a stator iron core and a three-phase flat wire winding installed in the stator iron core, the stator iron core and the flat wire winding There is insulating paper in between, the stator iron core is provided with Z wire slots, Z is a multiple of 12, the number of slots in each pole and each phase of the stator iron core is set to q, q is equal to 2, and each slot of the stator iron core is I flat conductors are embedded in the middle, the number of poles of the three-phase flat wire winding is 2P, each phase of the three-phase flat wire winding is provided with j parallel circuits, and each parallel branch is composed of W hairpin flat conductors , and W=Zi/6j, the hairpin flat conductors are inserted from one end of the stator core, and the input and output sides of each flat conductor are embedded in adjacent layers and are separated by K slots, that is, the first hairpin flat conductor input While embedded in the first layer of the first slot of the stator iron core, the output of the first flat hairpin conductor is embedded in the second layer of the k+1 slot of the stator iron core, and the input of the second flat hairpin conductor is embedded in the second layer of the stator iron core The first layer of the slot, the output side of the second flat conductor of the hairpin is embedded in the second layer of the k+2 slot of the stator core, and so on. After the first and second layers are embedded, the third and fourth layers are embedded, where K=Z/2P, q=Z/3*2P, so that the odd-numbered slot has a same-phase winding structure, and the even-numbered slot has a two-phase winding structure. By changing the bending angle of the flat conductor of the welding end, the input side to the output side of the welding end is changed. span.

Further, each of the parallel branches includes a full-pitch wave winding coil with a span of K, a short-distance layer-exchanged wave winding coil with a span of K-1, and a long-distance layer-exchanged wave winding coil with a span of K+2. , and some cases also include short-distance transposed wave winding coils with a span of K-1;

By changing layers and positions, each phase winding is formed into a short-distance winding, and all the input sides and output sides of each parallel branch are embedded in the same number of layers on different layers, so H is proposed to judge each parallel branch. Whether there is a basis for transposition coil, H=2W/ij, and H is an integer;

When H is equal to 1, each parallel branch passes through P coils for one layer change, and a total of i/2-1 layer changes are carried out, and there is no transposition coil;

When H is greater than 1, each parallel branch passes through P coils for one transposition, and passes through 2P coils for one layer exchange.

Further, when the number of parallel branches is 2, the coils of the 2 parallel branches of each phase are wound in opposite directions, the layers of the input side and the output side are opposite, and the input sides of the first coils of the two branches are respectively located in the same slot. first and last layer.

Further, when the parallel branch is 4, the number of the 1st and the 2nd branch of each phase is adjacent, the winding direction is the same, the number of layers is the same, the number of the 3rd and the 4th branch is adjacent, and the winding direction is the same. , the number of layers is the same, the coils of the 1st and 4th branches are wound in opposite directions, the number of layers of the input side and the output side are opposite, and the input sides of the first coil of the two branches are located in the first layer and the last layer of the same slot respectively. .

Compared with the prior art, the present invention includes the following beneficial effects:

1. The output side and input side of the flat hairpin conductor of the winding structure of the present invention are symmetrically distributed, and there is no circulating current between different parallel branches and different phases, and unnecessary winding losses are not introduced;

2. The winding structure can effectively weaken the harmonics on the stator side, improve the current sine, reduce the temperature rise caused by the current harmonics, and improve the NVH performance of the motor at the same time;

3. Because the AC copper loss caused by the skin effect of the windings with different same slots is smaller than that of windings with the same slot, the double-layer windings can also reduce AC losses, improve the efficiency at high speed, avoid local overheating of the windings, and improve the life of the motor;

4. The input end and output end of the parallel branch of each phase winding are simply combined in series and parallel, and the number of coil turns can also be adjusted, which is beneficial to the platform design and reduces the cost.

5. The winding structure is suitable for stators with various numbers of slots, layers and parallel branches, with flexible design and wide application.

Description of drawings

Fig. 1 is the structural representation of the present invention;

Fig. 2 is the structural representation of the flat wire winding of the present invention;

3 is an expanded view of all input sides and output sides of the three-phase flat wire winding of the present invention in a slot;

Fig. 4 is the structural representation of U-phase winding of the present invention;

5 is a schematic structural diagram of two groups of 4-turn coils of the present invention;

6 is a schematic structural diagram of two groups of single-turn coils connected in series according to the present invention;

FIG. 7 is a schematic structural diagram of a coil with a span of 6 in the present invention.

Detailed ways

As shown in FIG. 1 to FIG. 7 , a double-layer flat wire winding structure of a motor includes a stator iron core and a three-phase flat wire winding installed in the stator iron core. There is insulating paper, the stator iron core is provided with Z wire slots, Z is a multiple of 12, the number of slots in each pole and each phase of the stator iron core is set to q, q is equal to 2, and each slot of the stator iron core is embedded. i flat conductors, the number of poles of the three-phase flat wire winding is 2P, each phase of the three-phase flat wire winding is provided with j parallel circuits, each of the parallel branches is composed of W hairpin flat conductors, and W =Zi/6j, the flat hairpin conductors are inserted from one end of the stator core, the input and output sides of each flat conductor are embedded in adjacent layers and are separated by K slots, that is, the input side of the first flat hairpin conductor is embedded in the stator The first layer of the first slot of the iron core, the output edge of the first hairpin flat conductor is embedded in the second layer of the k+1th slot of the stator iron core, and the input edge of the second flat hairpin conductor is embedded in the second slot of the stator iron core. layer, the output side of the second flat conductor of the hairpin is embedded in the second layer of the k+2 slot of the stator core, and so on, after the 1st and 2nd layers are embedded, the 3rd and 4th layers are embedded, where K=Z/2P, q=Z /3*2P, so that the odd-numbered slot has a same-phase winding structure, and the even-numbered slot has a two-phase winding structure. By changing the bending angle of the flat conductor of the welding end, the span from the input side to the output side of the welding end is changed.

Each of the parallel branches includes a full-pitch wave winding coil with a span K, a short-distance layer-changing wave winding coil with a span of K-1, and a long-distance layer-changing wave winding coil with a span of K+2. Some cases also include short-distance transposed wave winding coils with a span of K-1;

By changing layers and positions, each phase winding is formed into a short-distance winding, and all the input sides and output sides of each parallel branch are embedded in the same number of layers on different layers, so H is proposed to judge each parallel branch. Whether there is a basis for transposition coil, H=2W/ij, and H is an integer;

When H is equal to 1, each parallel branch passes through P coils for one layer change, and a total of i/2-1 layer changes are carried out, and there is no transposition coil;

When H is greater than 1, each parallel branch passes through P coils for one transposition, and passes through 2P coils for one layer exchange.

When the number of parallel branches is 2, the coils of the two parallel branches of each phase are wound in opposite directions, the number of layers on the input side and the output side are opposite, and the input sides of the first coils of the two branches are respectively located on the first layer of the same slot. and the last layer.

When the number of parallel branches is 4, the number of slots of the first and second branches of each phase are adjacent, the winding direction is the same, and the number of layers is the same. The numbers are the same, the coils of the first and fourth branches are wound in opposite directions, and the layers of the input and output sides are opposite.

This embodiment includes a stator core 1 and a flat wire winding 2. The flat wire winding 2 is composed of symmetrically distributed U, V, and W three-phase windings. The stator core and the windings are separated by insulating paper, and the number of slots is 48. The number of motor poles is 8, three-phase motor, the number of slots per pole and phase is 2, and each phase has 4 parallel connections; 8 layers of flat conductors are embedded in each slot of the stator core from the slot to the bottom of the slot, then P=4 , W=16, H=1, j=1.

As shown in Figure 1, the three-phase winding adopts a Y-type connection, and all input and output sides are distributed in the stator core as shown in Figure 3, where A, B, and C represent the input sides of the three-phase winding, X, Y , Z represent the output side of the three-phase winding, that is, the current flows in from the conductor position indicated by A (or B, C), and flows out from the conductor position indicated by X (or Y, Z).

Each phase winding consists of 4 parallel branches, A represents the first parallel branch of U-phase winding 3, AA represents the second parallel branch of U-phase winding, AAA represents the third parallel branch of U-phase winding, and AAAA represents The fourth parallel branch of the U-phase winding can be obtained in the same way that B and C represent the V and W-phase windings respectively. A1 represents the first coil input side of the first parallel branch of the U-phase winding, and X1 represents the first coil output side of the first parallel branch of the U-phase winding.

Each parallel branch is formed by 16 coils 12 connected in series. The Arabic numerals indicate the connection sequence of the series branches. The current path of the first parallel branch of phase A is: A1-X1-A2-X2-A3-X3-A4-X4 -A5-X5-A6-X6-A7-X7-A8-X8-A9-X9-A10-X10-A11-X11-A12-X12-A13-X13-A14-X14-A15-X15-A15-X16

A1 is located in the 1st slot of the 1st layer, X1 is located in the 7th slot of the 1st layer, A2 is located in the 13th slot of the 1st layer, X2 is located in the 19th slot of the 1st layer, A3 is located in the 25th slot of the 1st layer, and X3 is located in the 1st layer. The 31st slot, A4 is located in the 37th slot of the first layer, X4 is located in the 43rd slot of the first layer, and the welding end span is 6;

A5 is located in the 48th slot of the 3rd layer, X5 is located in the 6th slot of the 4th layer, and the span from X4 to A5 is 5;

A6 is in the 12th slot of the 3rd layer, X6 is in the 18th slot of the 4th layer, A7 is in the 24th slot of the 3rd layer, X7 is in the 30th slot of the 4th layer, A8 is in the 36th slot of the 3rd layer, and X8 is in the 4th layer. The 42nd slot, the welding end span is 6;

A9 is located in the 2nd slot of the 5th layer, X9 is located in the 8th slot of the 6th layer, and the span from X8 to A9 is 8.

A10 is located in the 14th slot of the 5th layer, X10 is located in the 20th slot of the 6th layer, A11 is located in the 26th slot of the 5th layer, X11 is located in the 32nd slot of the 6th layer, A12 is located in the 38th slot of the 5th layer, and X12 is located in the 6th layer. The 44th slot, the span of the welding end is 6;

A13 is located in the 1st slot of the 7th layer, X12 is located in the 7th slot of the 8th layer, and the span from X12 to A13 is 5;

A14 is in the 13th slot of the 7th layer, X14 is in the 19th slot of the 8th layer, A15 is in the 25th slot of the 7th layer, X15 is in the 31st slot of the 8th layer, A16 is in the 37th slot of the 7th layer, and X16 is in the 8th layer. The 43rd slot, the welding end span is 6

AA1 is located in the 48th slot of the 1st layer, XX1 is located in the 6th slot of the 2nd layer, all input and output sides of the second parallel branch of phase A are adjacent to the number of slots of the first parallel branch, the number of layers is the same, and the coil is wound. to the same;

AAAA1 is located in the 1st slot of the 8th floor, XXXX1 is located in the 43rd slot of the 7th floor, AAAA1 and A1 are symmetrically distributed in the slot, the coils are wound in opposite directions, all the input and output sides of the third parallel branch of phase A are the same as the fourth The number of parallel branch slots is adjacent, the number of layers is the same, and the coil winding direction is the same.

As shown in Figure 4, the A-phase winding 3 has 4 input terminals, the first input terminal 4 is A1, the second input terminal 5 is AA1, the third input terminal 6 is AAA1, the fourth input terminal 7 is AAAA1 and 4 output terminals , the first output terminal 8 is X1, the second output terminal 9 is XX1, the third output terminal 10 is XXX1, and the fourth output terminal 11 is XXXX1. X1 and AAA1 are connected in series, XX1 and AAAA1 are connected in series, then the A-phase windings become 2-way parallel; on this basis, when XXX1 and AA1 are connected in series, the A-phase windings become 1-way in series.

The above embodiments only take the U-phase winding as an example, and similarly, the arrangement of the V-phase winding and the W-phase winding also follows the above-mentioned law of the U-phase winding.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Those skilled in the art can make changes to the present invention without departing from the spirit of the present invention.

Claims (4)

1. A double-layer flat wire winding structure of a motor comprises a stator core and three-phase flat wire windings arranged in the stator core, and is characterized in that insulating paper is arranged between the stator core and the flat wire windings, the stator core is provided with Z wire grooves, Z is a multiple of 12, the number of the grooves of each pole of each phase of the stator core is q, q is equal to 2, i flat conductors are embedded in each groove of the stator core, the number of the poles of the three-phase flat wire windings is 2P, each phase of the three-phase flat wire windings is provided with j parallel circuits, each parallel branch consists of W flat conductors, W = Zi/6j, the flat conductors are inserted from one end of the stator core, the input edge and the output edge of each flat conductor are embedded into adjacent layers and are uniformly separated by K grooves, namely, the input edge of a first flat conductor is embedded into the 1 st groove of the stator core, the output edge of the first flat conductor is embedded into the 2 nd groove of the stator core, the input edge of the second hairpin flat conductor is embedded into the 1 st layer of the 2 nd slot of the stator iron core, the output edge of the second hairpin flat conductor is embedded into the 2 nd layer of the K +2 nd slot of the stator iron core, and the process is analogized in turn, after the 1 and 2 layers are embedded, the second hairpin flat conductor is embedded into 3 and 4 layers, wherein K = Z/2P, and q = Z/3 x 2P, so that the odd number wire slots are of the same-phase winding structure, the even number wire slots are of the two-phase winding structure, and the span from the input edge to the output edge of the welding end is changed by changing the bending angle of the welding end hairpin flat conductor.

2. The double-layer flat wire winding structure of an electric machine according to claim 1, characterized in that: each parallel branch comprises a full-pitch wave winding coil with the span of K, a short-pitch layer-changing wave winding coil with the span of K-1, a long-pitch layer-changing wave winding coil with the span of K +2, and in some cases, a short-pitch transposition wave winding coil with the span of K-1;

forming short-distance windings on each phase of winding through layer changing and transposition, wherein all input edges and output edges of each parallel branch are embedded in different layers in the same number, so that H is drawn as a basis for judging whether each parallel branch has a transposition coil, H =2W/ij, and H is an integer;

when H is equal to 1, each parallel branch passes through P coils to carry out layer changing for 1 time, i/2-1 layer changing is carried out in total, and no transposition coil is arranged;

and when H is larger than 1, each parallel branch is transposed for 1 time through P coils, and layers are transposed for 1 time through 2P coils.

3. The double-layer flat wire winding structure of an electric machine according to claim 1, characterized in that: when the number of the parallel branches is 2, the winding directions of 2 parallel branch coils in each phase are opposite, the input sides and the output sides are opposite in layer number, and the input sides of the first coils of the two branches are respectively positioned in the first layer and the last layer of the same groove.

4. The double-layer flat wire winding structure of an electric machine according to claim 1, characterized in that: when the number of the parallel branch circuits is 4, the number of the 1 st branch circuit groove and the 2 nd branch circuit groove in each phase are adjacent, the winding direction is the same, the layer number is the same, the number of the 3 rd branch circuit groove and the 4 th branch circuit groove are adjacent, the winding direction is the same, the layer number is the same, the winding directions of the 1 st branch circuit coil and the 4 th branch circuit coil are opposite, the layer numbers of the input side and the output side are opposite, and the input side of the first coil of the two branch circuits is respectively located in the first layer and the last layer of the same groove.

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