Stator winding wiring method for hairpin motor, stator winding, and hairpin motor

Abstract

The present application relates to the technical field of motors, and discloses a stator winding wiring method for a hairpin motor, a stator winding, and a hairpin motor. The method comprises: on the basis of the design structure of a hairpin motor, dividing conductors in stator winding slots into a plurality of sub-windings along the inner diameter direction, wherein the design structure of the hairpin motor comprises a total number of slots, a total number of poles, and a total number of layers; determining the number of parallel branches of each of the plurality of sub-windings on the basis of the total number of poles, the number of parallel branches being a divisor of the total number of poles; on the basis of the total number of layers, determining the number of conductor layers forming each of the plurality of sub-windings; and determining the wiring structure of a stator winding on the basis of the number of parallel branches and the number of conductor layers. In the present application, the conductors in the stator winding slots are divided into a plurality of groups, and each group uses a different number of parallel branches. By means of the combination of the number of parallel branches and the number of conductor layers, more serial turns per phase can be realized, the selectable range of the number of series-connected turns per phase is greatly increased, and the expansion and optimization of the number of series-connected turns per phase winding are realized, thereby meeting the requirements of drive motors having different voltages and performances.

Description

Stator winding connection method of flat wire motor, stator winding and flat wire motor Technical Field

[0001] This application relates to the field of motor technology, and in particular to a stator winding connection method, stator winding, and flat wire motor of a flat wire motor. Background Technology

[0002] Flat wire motors are commonly used in the drive motors of new energy vehicles, offering advantages such as compact structure and high power density. Existing flat wire motors typically employ a 48-slot 8-pole or 54-slot 6-pole design, with the flat wire generally consisting of 6 or 8 layers. Among these, the 48-slot 8-pole design is the most widely used due to its smaller pole pitch and shorter end length.

[0003] Although flat wire motors are widely used, due to the limited number of poles, the number of parallel branches can only be selected from a few options. This means that the number of series turns per phase of the winding can only be selected from a limited number of schemes. For the different voltage and performance requirements of new energy vehicle motors, the adjustable range of the number of series turns per phase is very small, making it difficult to meet various design needs and adversely affecting the optimization of motor performance. Summary of the Invention

[0004] The main purpose of this application is to provide a stator winding connection method, stator winding and flat wire motor for a flat wire motor, in order to solve the technical problem that due to the number of poles, the number of parallel branches of a flat wire motor can only be selected in a few ways, which makes the adjustable range of the number of series turns per phase very small and difficult to meet various design requirements.

[0005] To achieve the above objectives, this application proposes a method for connecting the stator windings of a flat wire motor, the method comprising:

[0006] According to the design structure of the flat wire motor, the conductors in the stator winding slots of the flat wire motor are divided into multiple groups of sub-windings along the inner diameter direction. The flat wire motor is a three-phase motor. The design structure of the flat wire motor includes the total number of slots, the total number of poles, and the total number of layers.

[0007] Based on the total number of poles in the design structure, determine the number of parallel branches for each of the multiple sub-windings, where the number of parallel branches is a factor of the total number of poles;

[0008] The number of conductor layers for each of the multiple sub-windings is determined based on the total number of layers in the design structure.

[0009] The wiring structure of the stator winding is determined based on the number of parallel branches and the number of conductor layers.

[0010] In one embodiment, when the multiple sets of sub-windings are two sets of sub-windings, the two sets of sub-windings use different numbers of parallel branches. The step of dividing the conductors in the stator winding slots of the flat wire motor into multiple sets of sub-windings along the inner diameter direction according to the design structure of the flat wire motor includes:

[0011] According to the design structure of the flat wire motor, the slots are numbered sequentially from the bottom to the opening along the inner diameter direction of the stator winding of the flat wire motor.

[0012] The stator windings are divided into two sub-windings according to the order of their numbers.

[0013] In one embodiment, the number of conductor layers in both sets of sub-windings is even, and the sum of the number of conductor layers in the two sets of sub-windings is equal to the total number of layers.

[0014] In one embodiment, both sets of sub-windings are connected in a wave winding configuration, and the two sets of sub-windings are connected in series.

[0015] In one embodiment, the two sets of sub-windings include a first sub-winding and a second sub-winding. The two adjacent branches of the second sub-winding are connected in parallel and then connected in series with the branches of the first sub-winding.

[0016] In one embodiment, the conductor of the first sub-winding is located in the slot bottom direction, and the conductor of the second sub-winding is located in the slot opening direction;

[0017] The conductor cross-sectional area of ​​the first sub-winding is twice the conductor cross-sectional area of ​​the second sub-winding.

[0018] In one embodiment, the number of conductors and the phase of the conductors in each parallel branch of the first sub-winding and the second sub-winding are symmetrical.

[0019] The back electromotive force generated by each parallel branch of the first sub-winding and the second sub-winding is the same.

[0020] In one embodiment, the connection pitches of the first sub-winding and the second sub-winding do not affect each other.

[0021] In addition, to achieve the above objectives, this application also proposes a stator winding, which is obtained by connecting the stator windings of a flat wire motor as described above.

[0022] In addition, to achieve the above objectives, this application also proposes a flat wire motor, which includes a stator winding as described above.

[0023] One or more technical solutions proposed in this application have at least the following technical effects: This application proposes a stator winding wiring method for a flat wire motor. First, according to the design structure of the flat wire motor, the conductors in the stator winding slots of the flat wire motor are divided into multiple groups of sub-windings along the inner diameter direction. The flat wire motor is a three-phase motor, and the design structure of the flat wire motor includes the total number of slots, the total number of poles, and the total number of layers. Then, according to the total number of poles in the design structure, the number of parallel branches for each of the multiple groups of sub-windings is determined, and the number of parallel branches is a factor of the total number of poles. Next, according to the total number of layers in the design structure, the number of conductor layers for each of the multiple groups of sub-windings is determined. Finally, according to the number of parallel branches and the number of conductor layers, the wiring structure of the stator winding is determined. Because this application divides the conductors in the stator winding slots into multiple groups, each group adopts a different number of parallel branches, and through the combination of the number of parallel branches and the number of layers, more series turns per phase can be achieved, greatly improving the selectable range of series turns per phase, realizing the expansion and optimization of the series turns of each phase winding, thereby meeting the requirements of drive motors with different voltages and performance, and realizing the optimized design of the winding. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0025] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 is a schematic flowchart of the stator winding connection method of the flat wire motor provided in Embodiment 1 of this application;

[0027] Figure 2 is a wiring diagram showing different numbers of parallel branches provided in Embodiment 1 of this application;

[0028] Figure 3 is a wiring diagram of a 48-slot 8-pole flat wire winding with a1=2, a2=4, l1=2, l2=6 provided in Embodiment 1 of this application.

[0029] Figure 4 is a schematic diagram of the numbering and grouping of flat wire conductors in each slot with l1=2 and l2=6 provided in Embodiment 1 of this application;

[0030] Figure 5 is a wiring diagram of phase A of a 48-slot 8-pole flat wire winding with a1=2, a2=4, l1=2, l2=6 provided in Embodiment 2 of this application.

[0031] Figure 6 is a wiring diagram of phase A of a 48-slot 8-pole flat wire winding with a1=2, a2=4, l1=4, l2=4 and full pitch provided in Embodiment 2 of this application.

[0032] Figure 7 is a schematic diagram of the numbering and grouping of flat wire conductors in each slot with l1=4 and l2=4 provided in Embodiment 2 of this application;

[0033] Figure 8 is a wiring diagram of phase A of a 48-slot 8-pole flat wire winding with a1=2, a2=4, l1=4, l2=4 provided in Embodiment 2 of this application.

[0034] Figure 9 is a wiring diagram of phase A of a 48-slot, 8-pole short-pitch flat wire winding with a1=2, a2=4, l1=4, l2=4 provided in Embodiment 3 of this application.

[0035] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0036] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0037] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0038] It should be noted that the voltage (back EMF) of a flat-wire motor is matched by the number of turns in series in each phase winding. For a three-phase motor, the number of turns in series in each phase winding satisfies the following formula:

[0039] N1 = Z * l / (6a);

[0040] Where N1 is the number of turns in series per phase, Z is the number of slots, l is the number of conductor layers per slot, and a is the number of parallel branches.

[0041] Although 48-slot 8-pole flat wire motors are widely used, due to the 8 poles, the number of parallel branches 'a' can only be 1, 2, 4, or 8, as shown in Table 1:

[0042] Table 1: Number of series turns per phase N1 for a 48-slot 8-pole flat wire motor

[0043] As shown in Table 1, the number of turns N1 in series per phase of the winding can only be selected from a limited number of schemes. For the different voltage and performance requirements of new energy vehicle motors, the adjustable range of the number of turns in series per phase is very small, making it difficult to meet various design requirements.

[0044] For example, for a classic 48-slot, 8-pole, 8-layer flat wire motor, Table 1 gives the number of series turns per phase for different numbers of parallel branches 'a' and layers 'l'. For an 8-layer flat wire winding, only 16 and 32 turns per phase are available (8 and 64 are rarely used in practice and can be ignored); for a 6-layer flat wire winding, only 12 and 24 turns per phase are available (6 and 48 are rarely used in practice and can be ignored). It is difficult to match different voltage and performance requirements, which has an adverse effect on the optimization of motor performance.

[0045] To address the aforementioned issues, this application proposes a stator winding wiring method for a flat wire motor. By dividing the conductors in the slot into multiple groups, each group adopts a different number of parallel branches. Through the combination of the number of parallel branches and the number of layers, a greater number of series turns per phase can be achieved, greatly improving the selectable range of series turns per phase.

[0046] It should be noted that the executing entity of this embodiment can be an electronic device with data processing capabilities, such as a tablet computer or a personal computer, or a stator winding wiring device for a flat wire motor that executes the stator winding wiring method of the flat wire motor of this application. This embodiment does not limit this.

[0047] Based on this, this application provides a stator winding connection method for a flat wire motor. Referring to Figure 1, Figure 1 is a flowchart illustrating the first embodiment of the stator winding connection method for a flat wire motor provided in this application.

[0048] In this embodiment, the stator winding wiring method of the flat wire motor includes steps S10 to S40:

[0049] Step S10: According to the design structure of the flat wire motor, the conductors in the stator winding slots of the flat wire motor are divided into multiple groups of sub-windings along the inner diameter direction. The flat wire motor is a three-phase motor. The design structure of the flat wire motor includes the total number of slots, the total number of poles, and the total number of layers.

[0050] It should be noted that a flat-wire motor is a type of motor that uses flat-shaped copper wire windings. Compared to traditional round-wire motors, flat-wire motors can output greater power and torque within the same volume, while generating relatively less loss during operation, thus making them more widely used.

[0051] It should be noted that the stator winding is a set of coils installed on the stator of the motor.

[0052] The stator is the stationary part of the motor, and its windings are made of wire. These windings form a circuit through a specific connection method, generating a magnetic field when current flows through them. In flat-wire motors, flat wires are used to wind the windings. The stator windings interact with the rotor to achieve the motor's energy conversion and operation functions.

[0053] It should be noted that the conductor is the conductive part placed inside the stator core slot, that is, the flat copper wire.

[0054] It should be noted that multiple sets of sub-windings are sub-windings with different wiring methods that divide the conductors of the stator winding along the inner diameter direction.

[0055] It should be noted that the design structure is based on the winding specifications of the stator winding of a flat wire motor.

[0056] The total number of slots refers to the number of slots on the stator core of the motor used to house the windings.

[0057] The total number of poles represents the number of pole pairs in a motor, and the number of pole pairs determines the synchronous speed of the motor.

[0058] The total number of layers refers to how many layers the flat wires of the winding are arranged in layers.

[0059] For example, flat wire motors are generally designed with a 48-slot, 8-pole, 8-layer or a 54-slot, 6-pole, 8-layer configuration.

[0060] Step S20: Based on the total number of poles in the design structure, determine the number of parallel branches for each of the multiple sets of sub-windings, wherein the number of parallel branches is an approximation of the total number of poles.

[0061] It should be noted that the number of parallel branches is determined by dividing the various parts of the sub-winding into several groups, with the coils in each group connected in parallel in the circuit. The number of these parallel groups is the number of parallel branches.

[0062] It should be noted that the design of the number of parallel branches generally follows the principle of approximating the total number of poles (i.e., factors).

[0063] Step S30: Determine the number of conductor layers for each of the multiple sub-windings based on the total number of layers in the design structure.

[0064] It should be noted that the number of conductor layers refers to the number of spatially distributed layers of conductors that make up the winding.

[0065] For example, having two layers of conductors means that the winding is made up of two layers of conductors arranged and wound in a certain way.

[0066] It should be noted that the sum of the number of conductor layers in each sub-winding group is equal to the total number of layers.

[0067] Step S40: Determine the wiring structure of the stator winding based on the number of parallel branches and the number of conductor layers.

[0068] In this embodiment, by dividing the winding into multiple groups, each with a different number of parallel branches, and combining this with different conductor layers, the number of series turns per phase winding can be expanded and optimized. Therefore, more design schemes can be developed to meet the requirements of drive motors with different voltages and performance, achieving optimized winding design.

[0069] In one feasible implementation, the example of dividing the conductors in the slot into two groups is used for illustration, but this does not limit the scope of the solution. When the multiple sub-windings are divided into two sub-windings, the two sub-windings adopt different numbers of parallel branches. In this embodiment, step S10 may include the following steps: according to the design structure of the flat wire motor, numbering them sequentially from the bottom of the slot to the opening of the slot along the inner diameter direction of the stator winding of the flat wire motor; dividing the stator winding into two sub-windings according to the numbering order.

[0070] For example, for ease of understanding, refer to Figure 2, which is a wiring diagram of different numbers of parallel branches provided in Embodiment 1 of this application. In Figure 2, (a) and (b) are wiring methods commonly used in the prior art. As shown in the figure, A, B, and C represent three-phase access points. In Figure (a), the number of parallel branches a = 2, that is, A1 and A2 are connected in parallel in phase A, B1 and B2 are connected in parallel in phase B, and C1 and C2 are connected in parallel in phase C. In Figure (b), the number of parallel branches a = 4, that is, A1, A2, A3, and A4 are connected in parallel in phase A, B1, B2, B3, and B4 are connected in parallel in phase B, and C1, C2, C3, and C4 are connected in parallel in phase C.

[0071] Figure 2(c) is a schematic diagram of the stator winding connection method of the flat wire motor according to this embodiment. For the connection method proposed in this embodiment, the expression for the series conductors of each phase of the three-phase motor is as follows:

[0072] N1 = Z*(l1 / a1 + l2 / a2) / 6;

[0073] Where l1 is the number of conductor layers per slot in the first group, l2 is the number of conductor layers per slot in the second group, and the total number of conductor layers l = l1 + l2 (l can be 6, 8, 10, etc.); a1 is the number of parallel branches in the first group, and a2 is the number of parallel branches in the second group.

[0074] As shown in the figure, the number of parallel branches in the two groups are a1 = 2 and a2 = 4, respectively. That is, in phase A, A1 and A2 are connected in parallel, in A1, a1 and a2 are connected in parallel, and in A2, a3 and a4 are connected in parallel; in phase B, B1 and B2 are connected in parallel, in B1, b1 and b2 are connected in parallel, and in B2, b3 and b4 are connected in parallel; in phase C, C1 and C2 are connected in parallel, in C1, c1 and c2 are connected in parallel, and in C2, c3 and c4 are connected in parallel.

[0075] Taking a commonly used 48-slot 8-pole flat wire motor as an example, the number of parallel branches in the first group and the number of parallel branches in the second group, when selecting different conductor layers, are listed in Table 2 as follows:

[0076] Table 2: Number of series turns per phase N1 for 48-slot 8-pole flat wire motors with a1=2 and a2=4 flat wires

[0077] As can be seen from Table 2, compared to Table 1, more options are available for the number of series turns per phase. For example, for the classic 48-slot 8-pole 8-layer flat wire motor, in addition to the number of series turns shown in Table 1 (16, 32), it can also be extended to 20, 24, 28 and other series turns.

[0078] For further clarification, refer to Figure 3, which is a wiring diagram of a 48-slot, 8-pole, full-pitch flat wire winding with a1=2, a2=4, l1=2, and l2=6 provided in Embodiment 1 of this application. As shown in the figure, dashed lines represent crown ends, and solid lines represent welded ends. This winding has 4 pole pairs and 2 parallel branches. It includes three-phase windings (A, B, and C), with polarities of N and S, and phase combinations of A, -A, B, -B, C, and -C. Slot numbers range from 1 to 48.

[0079] Referring to Figures 3 and 4, Figure 4 is a schematic diagram of the flat wire conductor numbering and grouping in each slot (l1=2, l2=6) provided in Embodiment 1 of this application. Figure 3 shows the flat wire conductor numbering in the slots of the wiring method (a total of 48 slots, only one slot is shown in the figure), comprising 8 layers from a to h. A and b are group 1 (each layer has A1, A2, B1, B2, C1, and C2, which are connected in parallel to form different combinations). C to h are group 2 (each layer has a1 to a4, b1 to b4, and c1 to c4, which are connected in parallel to form different combinations). Group 1 has 2 layers and 2 parallel branches, while group 2 has 6 layers and 4 parallel branches. The equivalent number of series turns per phase is 20 (which cannot be achieved using the traditional 8-layer flat wire design method). In this example, both sets of windings use full-pitch, wave windings. The a1 and a2 of the second set are first connected in parallel and then in series with the A1 of the first set. The a3 and a4 of the second set are first connected in parallel and then in series with the A2 of the first set.

[0080] Conventional 48-slot, 8-pole, 8-layer flat wire windings, due to their single parallel branch count of 1, 2, 4, or 8, can only achieve series turns per phase of 32 or 16 (64 or 8 turns are rarely used). However, the method in this embodiment provides two parallel branch counts: a first group with 2 parallel branches and a second group with 4 parallel branches, allowing for series turns per phase of 20, 24, or 28. Similar effects are achieved for 6-layer flat wire windings. Therefore, more design options can be developed to meet the requirements of drive motors with different voltages and performance characteristics, achieving optimized winding design.

[0081] In this embodiment, the flat wire winding is divided into two groups along the inner diameter direction (as shown in Figures 3 and 4, the 48-layer 8-pole 8-layer flat wire motor winding is numbered a to h sequentially from the bottom of the slot to the opening of the slot along the inner diameter direction, with layers a and b set as the first group and layers c to h set as the second group). The two groups have different numbers of parallel branches, with the first group having 2 parallel branches and the second group having 4 parallel branches. Through the above grouping, the number of series turns of each phase winding can be expanded and optimized.

[0082] In one feasible implementation, the number of conductor layers in both sets of sub-windings is even, and the sum of the number of conductor layers in the two sets of sub-windings is equal to the total number of layers.

[0083] In this embodiment, each group contains an even number of winding layers, which can have different combinations. For example, if the number of conductor layers per slot is 8, the number of layers in the first winding group can be 2, 4, or 6 (the corresponding number of layers in the second winding group is 6, 4, or 2 respectively); if the number of conductor layers per layer is 6, the number of layers in the first winding group can be 2 or 4 (the corresponding number of layers in the second winding group is 4 or 2 respectively).

[0084] In the technical solution provided in this embodiment, the flat wire winding is divided into two groups along the inner diameter direction. The two groups have different numbers of parallel branches and different numbers of conductor layers. Finally, the wiring structure of the stator winding is determined according to the number of parallel branches and the number of conductor layers. This allows for a greater number of series turns per phase, greatly improving the selectable range of series turns per phase, and realizing the expansion and optimization of the number of series turns per phase winding. This can meet the requirements of drive motors with different voltages and performance, and achieve optimized winding design.

[0085] Based on the first embodiment of this application, in the second embodiment of this application, the same or similar content as the first embodiment described above can be referred to the above description, and will not be repeated hereafter.

[0086] In this example, both sets of sub-windings are connected in a wave winding configuration, and the two sets of sub-windings are connected in series.

[0087] The two sets of sub-windings include a first sub-winding and a second sub-winding. The two adjacent branches of the second sub-winding are connected in parallel and then connected in series with the branches of the first sub-winding.

[0088] It should be noted that a wave winding is a connection method for the armature winding of a DC motor. All coils of the same polarity are connected in series in a specific order to form a wave-like winding. Wave windings have fewer branch pairs and larger branch currents, making them suitable for low-voltage, high-current motors.

[0089] For illustrative purposes, please refer to Figure 5. Figure 5 is a wiring diagram of phase A of a 48-slot, 8-pole, full-pitch flat wire winding with a1=2, a2=4, l1=2, and l2=6, provided in Embodiment 2 of this application. The wiring method in Figure 5 is consistent with that in Figure 3, except that Figure 3 shows a complete wiring diagram including the three-phase windings A, B, and C; while Figure 5, based on Figure 3, only shows the wiring diagram of phase A. The phase windings B and C are similar to phase A, but spatially separated by 120 degrees. The purpose of Figure 5 is to facilitate a more concise and clear description of the wiring method of this invention.

[0090] In this embodiment, each phase winding of the first group and the second group adopts the wave winding connection method (as shown in Figure 5). The first group and the second group adopt the series connection method (as shown in Figure 2(c)). After the two adjacent branches of the second group are connected in parallel, they are connected in series with a branch of the first group (as shown in Figure 5, the first group includes two branches A1 and A2, and the second group includes four branches a1, a2, a3, and a4. Among them, after a1 and a2 are connected in parallel, they are connected in series with A1, and after a3 and a4 are connected in parallel, they are connected in series with A2).

[0091] Furthermore, in this example, the conductor of the first sub-winding is located in the slot bottom direction, and the conductor of the second sub-winding is located in the slot opening direction; the cross-sectional area of ​​the conductor of the first sub-winding is twice the cross-sectional area of ​​the conductor of the second sub-winding.

[0092] In this embodiment, since the first group has 2 parallel branches and the second group has 4 parallel branches, the current in the first group conductor is twice that in the second group conductor. To maintain the same electrical density, the cross-sectional area of ​​the first group conductor is approximately twice that of the second group conductor. Therefore, the overall effect is that the flat wire height is not equal (as shown in Figure 4). The cross-sectional area of ​​the conductor located at the slot is smaller, and the skin effect and proximity effect are often more obvious in the conductor at the slot. After adopting this scheme, it is more beneficial for the conductor near the slot to reduce the influence of the skin effect and proximity effect, which is beneficial to reduce the AC copper loss of the stator and thus improve the efficiency of the motor.

[0093] Furthermore, in this example, the number of conductors and the phase of the conductors in each parallel branch of the first sub-winding and the second sub-winding are symmetrical; the back EMF generated by each parallel branch of the first sub-winding and the second sub-winding are the same.

[0094] In this embodiment, the wiring method of each parallel branch of the first and second groups of windings is symmetrical, that is, the number of conductors and the spatial phase of each parallel branch of the first group (including 2 parallel branches) are completely symmetrical, and the generated back EMF is exactly the same. The number of conductors and the spatial phase of each parallel branch of the second group (including 4 parallel branches) are also completely symmetrical, and the generated back EMF is also exactly the same, so as to avoid the generation of circulating current.

[0095] It should be noted that different combinations of the number of layers can achieve the method of this embodiment. For ease of understanding, please refer to Figure 6. Figure 6 is the wiring diagram of phase A of the 48-slot 8-pole full-pitch flat wire winding with a1=2, a2=4, l1=4, l2=4 provided in Embodiment 2 of this application.

[0096] Compared to Figure 5, Figure 6 shows that the number of layers in groups 1 and 2 has been changed from 2 and 6 layers to 4 and 4 layers respectively, while the wiring method remains similar to Figure 5. This figure is provided as another example of this scheme to illustrate that it can be implemented for different combinations of layer numbers. For this scheme, the equivalent number of series turns per phase is 24 (which cannot be achieved using the traditional 8-layer flat wire design method).

[0097] Referring now to Figure 7, which is a schematic diagram of the flat wire conductor numbering and grouping in each slot (l1=4, l2=4) provided in Embodiment 2 of this application, Figure 7 shows the flat wire conductor numbering and grouping in the slot corresponding to the wiring method in Figure 6. The number of layers in Group 1 and Group 2 are 4 and 4 respectively, and the conductor cross-sectional area of ​​Group 1 is twice that of Group 2.

[0098] It should be noted that even when the number of parallel branches and the number of winding layers in each group are exactly the same, the wiring method can still be different. For ease of understanding, please refer to Figure 8, which is the wiring diagram of phase A of the 48-slot 8-pole full-pitch flat wire winding with a1=2, a2=4, l1=4, l2=4 provided in Embodiment 2 of this application.

[0099] Compared to Figure 6, Figure 8 shows the same number of parallel branches and winding layers in each group, but the wiring method for the second group is different. In Figure 6, branches a1 and a2 in the second group differ by one slot number (i.e., adjacent), and branches a3 and a4 also differ by one slot number. In Figure 8, a1, a2, a3, and a4 are evenly distributed in space (differences of 12 slot numbers). This figure is to illustrate that when the number of parallel branches and winding layers in each group are exactly the same, there are multiple wiring methods.

[0100] In the technical solution provided in this embodiment, adopting this solution is more conducive to reducing the influence of skin effect and proximity effect on conductors near the slot, which is beneficial to reducing the AC copper loss of the stator and thus improving the efficiency of the motor.

[0101] Based on the above embodiments of this application, in the third embodiment of this application, the same or similar content as the above embodiments can be referred to the above description, and will not be repeated hereafter.

[0102] In this example, the connection pitches of the first sub-winding and the second sub-winding do not affect each other.

[0103] It should be noted that pitch, also known as winding pitch, refers to the number of slots spanned between the two effective sides of a winding element.

[0104] For illustrative purposes, please refer to Figure 9, which is a wiring diagram of phase A of a 48-slot, 8-pole short-pitch flat wire winding with a1=2, a2=4, l1=4, and l2=4 provided in Embodiment 3 of this application. The number of parallel branches and the number of winding layers in each group are exactly the same in Figure 9 and Figure 6. The difference is that the second group in Figure 6 uses a full-pitch winding, while the second group in Figure 9 uses a short-pitch winding. Both full-pitch and short-pitch are commonly used winding connection methods; short-pitch can appropriately improve the harmonic content of the winding. This figure is mainly to illustrate that the pitches of the first and second groups in this scheme are relatively independent, allowing for both full-pitch and short-pitch windings to coexist.

[0105] In this embodiment, the wiring methods of the first group of windings and the second group of windings are relatively independent. Except for the number of parallel branches, their pitch (as shown in Figure 6, the first group and the second group of windings both use full pitch, while in Figure 9, the first group uses full pitch and the second group uses short pitch) and wiring methods can be different.

[0106] It should be noted that the above examples are only for understanding this application and do not constitute a limitation on the stator winding connection method of the flat wire motor of this application. Any simple modifications based on this technical concept are within the protection scope of this application.

[0107] This application also provides a stator winding, which is obtained by wiring using the stator winding wiring method of the flat wire motor as described above.

[0108] The stator winding provided in this application, employing the stator winding connection method for flat wire motors described in the above embodiments, solves the technical problem that flat wire motors, due to their limited pole numbers, only have a few options for the number of parallel branches, resulting in a very small adjustable range for the number of series turns per phase, making it difficult to meet various design requirements. Compared with the prior art, the beneficial effects of the stator winding provided in this application are the same as those of the stator winding connection method for flat wire motors provided in the above embodiments, and other technical features in the stator winding are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0109] This application also provides a flat wire motor, which includes the stator winding as described above. Compared with the prior art, the beneficial effects of the flat wire motor provided in this application are the same as the beneficial effects of the stator winding wiring method of the flat wire motor provided in the above embodiments, and other technical features of the flat wire motor are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0110] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.

Claims

1. A method for connecting the stator windings of a flat wire motor, characterized in that, The method includes: According to the design structure of the flat wire motor, the conductors in the stator winding slots of the flat wire motor are divided into multiple groups of sub-windings along the inner diameter direction. The flat wire motor is a three-phase motor. The design structure of the flat wire motor includes the total number of slots, the total number of poles, and the total number of layers. Based on the total number of poles in the design structure, determine the number of parallel branches for each of the multiple sub-windings, where the number of parallel branches is a factor of the total number of poles; The number of conductor layers for each of the multiple sub-windings is determined based on the total number of layers in the design structure. The wiring structure of the stator winding is determined based on the number of parallel branches and the number of conductor layers.

2. The method as described in claim 1, characterized in that, When the multiple sets of sub-windings are divided into two sets of sub-windings, the two sets of sub-windings use different numbers of parallel branches. The step of dividing the conductors in the stator winding slots of the flat wire motor into multiple sets of sub-windings along the inner diameter direction according to the design structure of the flat wire motor includes: According to the design structure of the flat wire motor, the slots are numbered sequentially from the bottom to the opening along the inner diameter direction of the stator winding of the flat wire motor. The stator windings are divided into two sub-windings according to the order of their numbers.

3. The method as described in claim 2, characterized in that, The number of conductor layers in both sets of sub-windings is even, and the sum of the number of conductor layers in the two sets of sub-windings is equal to the total number of layers.

4. The method according to any one of claims 2 to 3, characterized in that, Both sets of sub-windings adopt the wave winding connection method, and the two sets of sub-windings are connected in series.

5. The method as described in claim 4, characterized in that, The two sets of sub-windings include a first sub-winding and a second sub-winding. The two adjacent branches of the second sub-winding are connected in parallel and then connected in series with the branches of the first sub-winding.

6. The method as described in claim 5, characterized in that, The conductor of the first sub-winding is located in the slot bottom direction, and the conductor of the second sub-winding is located in the slot opening direction; The conductor cross-sectional area of ​​the first sub-winding is twice the conductor cross-sectional area of ​​the second sub-winding.

7. The method as described in claim 5, characterized in that, The number of conductors and the phase of the conductors in each parallel branch of the first sub-winding and the second sub-winding are symmetrical. The back electromotive force generated by each parallel branch of the first sub-winding and the second sub-winding is the same.

8. The method as described in claim 7, characterized in that, The connection pitches of the first sub-winding and the second sub-winding do not affect each other.

9. A stator winding, characterized in that, The stator winding is obtained by wiring using the stator winding wiring method of a flat wire motor as described in any one of claims 1 to 8.

10. A flat wire motor, characterized in that, The flat wire motor includes the stator winding as described in claim 9.

Images