Flat wire continuous wave winding, stator and motor

Abstract

The present invention belongs to the technical field of test equipment, and specifically provides a flat wire continuous wave winding, a stator and a motor. The present invention aims to solve the problem of difficulty in production and easy damage caused by many welding spots of flat wire motors in the prior art. The flat wire continuous wave winding of the present invention includes an inlet terminal, an outlet terminal and an S-shaped wave winding located between the inlet terminal and the outlet terminal. The number of winding layers of the flat wire continuous wave winding is 2N, and the pitch is y. A jump winding part is provided at the junction of the Nth layer and the N+1th layer of the flat wire continuous wave winding. The pitch of each phase conductor group at the jump winding part is y+1, wherein N and y are both natural numbers greater than or equal to 1. The flat wire continuous wave winding of the present invention adopts a flat wire continuous winding scheme to reduce welding spots.

Description

Technical Field

[0001] The invention belongs to the technical field of motors, and specifically provides a flat wire continuous wave winding, a stator and a motor. Background Art

[0002] The main development trend of new energy vehicle motors is miniaturization and high speed, and miniaturization will inevitably require a significant increase in motor power density. From the technical requirements, the peak power density of new energy vehicle drive motors must reach 4kw / kg, but currently this figure is only 3.2-3.3kw / kg, so at least 30% improvement is still needed.

[0003] The difference between flat wire motors and round wire motors lies in the way the copper wire is formed. Flat wire is conducive to improving the slot fill rate of the motor. Generally, the slot fill rate of round wire motors is about 40%, while the slot fill rate of flat wire motors can reach more than 60%. The improvement of the slot fill rate means that more copper wire can be filled in under the premise of unchanged space, which will generate stronger magnetic field strength and improve power density. In the long run, flat wire motors are the development direction of future drive motors.

[0004] The armature windings of flat wire motors all use wave windings. The wires are formed in two ways: U-pin and I-pin. Both of these forming methods require welding at the ends of the windings. U-pin is welded at one end, and I-pin is welded at both ends. The quality of each welding point affects the life of the entire motor. The more welding points there are, the higher the probability and risk of failure. At the same time, U-pin and I-pin motors are limited by the degree of process automation, the design flexibility is poor, and the expansion of the power range of the motor platform is limited.

[0005] Among them, U-pin is a flat copper wire with one end pre-formed and then inserted into the stator core slot, and the other end is twisted into a frog leg shape and then welded together to form a wave winding. I-pin is a straight copper wire directly inserted into the stator core slot, and then both ends are twisted into a frog leg shape and welded together to form a wave winding. The number of welds is large. If one of the welds fails, the stator winding will fail. The more welds there are, the higher the risk of failure, and the consistency and reliability of the product will be difficult to guarantee.

[0006] In order to realize mass production automation, the number of parallel branches of U-pin and I-pin is generally less than or equal to 2. When the number of parallel branches increases, the number of special-shaped pins will also increase. The structure wiring is complex and there are many types of tooling and molds, which is not conducive to realizing mass production automation. Due to the small number of parallel branches, there are great limitations on the increase of motor power.

[0007] Accordingly, those skilled in the art are in urgent need of solving the problem of difficult production and easy damage caused by the large number of welding points in the flat wire motor in the prior art. Summary of the invention

[0008] In order to solve the above-mentioned problems in the prior art, that is, to solve the problems of difficult production and easy damage caused by the large number of welding points of flat wire motors in the prior art, the present invention provides a flat wire continuous wave winding, characterized in that the flat wire continuous wave winding includes an input terminal, an output terminal and an S-shaped wave winding located between the input terminal and the output terminal, the number of winding layers of the flat wire continuous wave winding is 2N, the pitch is y, and a jump winding part is provided at the connection between the Nth layer and the N+1th layer of the flat wire continuous wave winding, and the pitch of each phase conductor group at the jump winding part is y+1; wherein N and y are both natural numbers greater than or equal to 1.

[0009] In the preferred technical solution of the above flat wire continuous wave winding, a staggered winding portion is further provided in the S-shaped wave winding, and at the staggered winding portion, the relative positions of the wires in each phase wire group are respectively arranged in a staggered arrangement in the form of y-1 and y+1.

[0010] In the preferred technical solution of the above flat wire continuous wave winding, the wires in the wire group of each phase are connected in parallel with each other.

[0011] In the preferred technical solution of the above flat wire continuous wave winding, the parallel connection form is a star connection or a triangle connection.

[0012] In the preferred technical solution of the above flat wire continuous wave winding, the number of the parallel branches is 2 or 4.

[0013] In the preferred technical solution of the above flat wire continuous wave winding, the wires in the wire group of each phase are connected in series.

[0014] In the preferred technical solution of the flat wire continuous wave winding, the wires in each phase wire group of the flat wire continuous wave winding are all complete wires, and no welding points appear in the S-shaped wave winding.

[0015] In the preferred technical solution of the above flat wire continuous wave winding, N=2, and Y=6.

[0016] The present invention further provides a stator, characterized by comprising winding slots, in which the flat wire continuous wave winding described in any one of the above technical solutions is wound.

[0017] The present invention also provides a motor, characterized in that it comprises a stator, and the stator is the stator described in the above technical solution.

[0018] It can be understood by those skilled in the art that, in the technical solution of the present invention, the flat wire continuous wave winding includes an input terminal, an output terminal and an S-shaped wave winding located between the input terminal and the output terminal, the number of winding layers of the flat wire continuous wave winding is 2N, the pitch is y, and a jump winding portion is provided at the junction of the Nth layer and the N+1th layer of the flat wire continuous wave winding, and the pitch of each phase conductor group at the jump winding portion is y+1, wherein N and y are both natural numbers greater than or equal to 1.

[0019] Through the above-mentioned setting method, the flat wire continuous wave winding of the present invention adopts a solution of continuous winding of the flat wire. Compared with the prior art of welding after plugging, the number of solder joints is significantly reduced. The number of solder joints varies with the length of the flat wire used for the flat wire continuous wave winding. If the length of the flat wire is sufficient, zero solder joints can be achieved by directly inserting it from the beginning and then winding it out. However, due to processing and cost limitations, two flat wires may be used for winding after welding, or one or more solder joints may be added between windings. However, the number of solder joints of this solution can also be controlled to be very small. Therefore, the flat wire continuous wave winding of the present invention significantly reduces the number of solder joints. In addition, the continuous winding of flat wire also brings a problem, that is, the conventional continuously wound flat wire has an uneven phase distribution after full-pitch winding. The harmonic component in the no-load back EMF is large, the torque fluctuation is large, and a large noise will be generated. In order to make the motor noise smaller, a jump winding part is creatively added at the junction of the Nth layer and the N+1th layer of the flat wire continuous wave winding with 2N winding layers. The pitch of each phase conductor group in the jump winding part is y+1, which can meet the phase difference and balance the phase difference, thereby achieving the short-distance effect. The short-distance winding cuts off the harmonic component in the no-load back EMF, thereby making the back EMF waveform more sinusoidal and the torque fluctuation smaller, thereby improving the noise caused by the motor torque fluctuation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The flat wire continuous wave winding, stator and motor of the present invention are described below with reference to the accompanying drawings. In the accompanying drawings:

[0021] Figure 1 It is a schematic diagram of the stator structure of a flat wire motor that is welded after plugging in the prior art;

[0022] Figure 2 The winding diagram of the A-phase line in the three-phase line of the flat wire continuous wave winding of the present invention;

[0023] Figure 3 for Figure 2 Enlarged view of G in the middle;

[0024] Figure 4 for Figure 2 The enlarged view of the H in the middle;

[0025] Figure 5 for Figure 2 The enlarged view of point I in the middle;

[0026] Figure 6 A phase line distribution diagram of a part of winding slots of the stator of the present invention;

[0027] Figure 7a A star connection method of a parallel branch of the present invention;

[0028] Figure 7b The star connection method of two parallel branches of the present invention;

[0029] Figure 7c The star connection method of the four parallel branches of the present invention;

[0030] Figure 8a A triangle connection method for a parallel branch of the present invention;

[0031] Figure 8b A triangle connection method of two parallel branches of the present invention;

[0032] Figure 8c This is the triangle connection method of the four parallel branches of the present invention. DETAILED DESCRIPTION

[0033] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. Those skilled in the art can make adjustments as needed to adapt to specific applications. For example, although the specification is described as an example in which the flat wire is a whole piece of flat wire that is continuously wound from beginning to end and has no welding spots, the present invention can obviously adopt a method of winding after two shorter flat wires are welded, as long as the welding spots can be reduced compared to the prior art.

[0034] It should be noted that in the description of the present invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0035] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] It should be noted that the three-phase motor can be expressed as UVW phases or ABC phases. For the sake of unified expression, ABC phases are used in the present invention, which correspond to the three phases UVW respectively. Positive and negative represent the direction of current. For example, A+ represents that the current is transmitted from the top to the bottom of the stator along the flat wire, and A- represents that the current is transmitted from the bottom to the top of the stator along the flat wire.

[0037] In addition, in order to more clearly describe the wiring of the present invention, Figures 2 to 5 The winding method of the conductor group of phase A is the same as that of the conductor group of phase B and phase C. The only difference is that the inlet and outlet are different. For example, Figure 2 As shown, the four wire inlets of phase A can be slot 1, slot 2, slot 7, and slot 8 respectively, while phase B can be slot 3, slot 4, slot 9, and slot 10, which are not listed one by one.

[0038] Figure 1 It is a stator of a common flat wire motor in the prior art. Figure 1 The main purpose of the present invention is to help readers understand the general structure of the present invention. The present invention improves the structure of the stator into a continuous winding scheme of the internal flat wire. There is no major change to the stator structure itself. The structure of the stator is similar, and there are many examples in the prior art, so it will not be elaborated.

[0039] Refer to the following Figures 2 to 8c The specific implementation of the present invention is described in detail. Take 48 slots and 8 poles, 8 conductors in each slot as an example, the number of slots per pole is 2, each slot has 8 conductors, and the winding expansion diagram of phase A is as follows Figures 2 to 5 As shown, at this time, the number of winding layers of the flat wire continuous wave winding is 2N=4, that is, N=2, and the pitch of the A phase conductor group y=6.

[0040] Combination Figure 2 and Figure 3 It can be seen that the A phase conductor group has four conductors A1, A2, A3, and A4 for winding, and its incoming line end is Figure 2 The outlet terminals are marked with A1, A2, A3, and A4 on the middle layer. Figure 2At the positions marked with A1', A2', A3' and A4' in the middle four layers, S-shaped wave windings are formed at the incoming and outgoing ends, and staggered winding parts and skipped winding parts are provided between the S-shaped wave windings.

[0041] The normal winding pitch is y = 6, such as Figure 2 and Figure 3 As shown, Figure 3 for Figure 2 The enlarged view at G in the middle shows a typical conventional winding method, that is, the slots through which the A1 wire passes are 7→13→19, and each is exactly 6 slots per winding, that is, the pitch y = 6. Similarly, the pitch y of A2, A3 and A4 at G is 6.

[0042] The pitch of the jump winding part is 7, such as Figure 2 and Figure 4 As shown in the figure, the four wires A1, A2, A3, and A4 jump forward together. Figure 2 The two ellipse circles in the middle show the slots through which the wires of the jumper pass. Figure 2 and Figure 4 From the above, the slots that A1 wire passes through are 43→2→8, and the pitch from slot 43 to slot 2 is y=7, thus completing the jump, and after slot 2, the pitch y=6 is restored. Similarly, the slots that A2 wire passes through are 44→3→9, the slots that A3 wire passes through are 1→8→14, and the slots that A4 wire passes through are 2→9→15. Each wire of the A-phase wire group completes the jump at the junction of the second and third layers, that is, the jump with a pitch of y+1, and then resumes normal winding.

[0043] The pitches of two adjacent wires in the offset winding part are 5 and 7 respectively. Figure 2 and Figure 5 As shown, Figure 2 The areas circled in the middle are all jump winding parts. Figure 2 Take I in the middle as an example, the slots through which the A1 wire passes are 19→26, that is, the pitch becomes 7, and the slots through which the A2 wire passes are 20→25, that is, the pitch becomes 5, thus completing the staggered winding. Similarly, the slots through which the A3 wire passes are 25→32, and the slots through which the A4 wire passes are 26→31, and then normal winding is resumed.

[0044] The advantage of the above arrangement is that the generation of solder joints is avoided through the continuous wave winding design.

[0045] Through the design of the staggered winding part, the phase difference can be balanced, thereby satisfying the design of multiple branches. Compared with the single-branch design without such staggered winding in the prior art, the design range of the branch number is widened, so that a higher power motor can be made when designing the motor, and there is no need to increase the opposite sex pins and solder joints.

[0046] Through the design of the jump winding part, the winding phase is changed to a short-distance winding phase distribution of a double-layer winding, which cuts the harmonic component and makes the motor performance more excellent.

[0047] So far, the basic rules of the flat wire continuous wave winding of the present invention have been introduced. The final phase distribution and current flow distribution in the stator slots are as follows: Figure 6 As shown, the whole winding is completed. Figure 6 Only a part of them are listed. Although the pitch of the flat wire continuous wave winding is 6, the staggered winding scheme makes the winding phase become a short-distance winding phase distribution of a double-layer winding. The short-distance coefficient = sin(5 / 6*90°). Compared with the full-distance winding, the short-distance winding cuts the harmonic component of the no-load back-EMF, making the back-EMF waveform more sinusoidal, the torque fluctuation smaller, and improving the noise caused by the motor torque fluctuation.

[0048] In addition, since the flat wire continuous wave winding of the present invention adopts the technical solution of the jump winding part, the flat wire continuous wave winding of the present invention can realize the design of multiple parallel branches. Figures 7a to 8c Some embodiments of parallel branches are listed respectively, which are star connection with one parallel branch, two parallel branches, four parallel branches, and triangle connection with one parallel branch, two parallel branches, and four parallel branches.

[0049] It should be noted that the above-mentioned implementation mode is only used to illustrate the principle of the present invention and is not intended to limit the scope of protection of the present invention. Without departing from the principle of the present invention, those skilled in the art can adjust the above-mentioned structure so that the present invention can be applied to more specific application scenarios.

[0050] For example, in an alternative embodiment, the values ​​of N and y can obviously be flexibly selected according to actual needs, and the structural design of the jump winding part and the offset winding part can be adjusted accordingly to adapt to different motor designs. However, these schemes are simple deformations and extensions of the present invention. These designs do not deviate from the design principles of the present invention and therefore fall within the scope of protection of the present invention.

[0051] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A flat wire continuous wave winding, characterized in that: The flat wire continuous wave winding comprises an inlet terminal, an outlet terminal and an S-shaped wave winding located between the inlet terminal and the outlet terminal. The number of winding layers of the flat wire continuous wave winding is 2N, and the pitch is y. A jump winding portion is provided at the junction of the Nth layer and the N+1th layer of the flat wire continuous wave winding, and the pitch of each phase conductor group at the jump winding portion is y+1; Wherein, N and y are both natural numbers greater than or equal to 1.

2. The flat wire continuous wave winding according to claim 1, characterized in that: The S-shaped wave winding is also provided with a staggered winding portion, at which the relative positions of the wires in each phase wire group are respectively arranged in a staggered arrangement in the form of y-1 and y+1.

3. The flat wire continuous wave winding according to claim 2, characterized in that: The conductors in the conductor group of each phase are connected in parallel.

4. The flat wire continuous wave winding according to claim 3, characterized in that: The parallel connection form is a star connection or a triangle connection.

5. The flat wire continuous wave winding according to claim 3, characterized in that: The number of the parallel branches is 2 or 4.

6. The flat wire continuous wave winding according to claim 2, characterized in that: The wires in the wire group of each phase are connected in series.

7. The flat wire continuous wave winding according to claim 1, characterized in that: The wires in each phase wire group of the flat wire continuous wave winding are all complete wires, and no welding points appear in the S-shaped wave winding.

8. The flat wire continuous wave winding according to claim 1, characterized in that: N=2, and y=6.

9. A stator, characterized in that The invention comprises a winding groove in which the flat wire continuous wave winding according to any one of claims 1 to 8 is wound.

10. A motor, characterized in that It comprises a stator, and the stator is the stator according to claim 9.

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