Odd-layer flat wire motor stator and winding structure

Abstract

The invention discloses an odd-layer flat wire motor stator and winding structure, which comprises a stator iron core, the stator iron core is formed by laminating a plurality of silicon steel sheets, a plurality of rectangular grooves with the same size are formed in the stator iron core according to a circumferential array, and a plurality of conductors are inserted into the plurality of rectangular grooves. Taking 54-slot five-layer coils as an example, the invention introduces an odd number H-pin winding patent of coils 5, 7 and the like of each layer of the winding, a stator adopts an arrangement mode of the odd number of the coils and a composite distribution winding arrangement mode, so that magnetomotive forces generated by the coils of all phases have phase differences, all the magnetomotive forces are mutually superposed, and the winding structure is formed. The superposed magnetomotive force is smaller than the superposed magnetomotive force in the prior art, so that the motor can weaken harmonic waves generated by the motor to a certain extent, especially can greatly weaken fifth harmonic waves and seventh harmonic waves, can reduce torque pulsation and noise, and can improve the performance of the motor.

Description

Technical Field

[0001] The present invention relates to the technical field of motor stators, and more specifically, to an odd-layer flat wire motor stator and winding structure. Background Art

[0002] In the field of electric vehicles, motors have higher efficiency and temperature rise requirements. With the application of flat wire stator technology, electric vehicle motors are gradually adopting flat wire forming windings. However, for flat wire hairpin motors, the uneven arrangement between the same-phase branches is prone to inconsistent potentials, resulting in the formation of circulating currents between the branches, affecting the efficiency and temperature rise of the motor.

[0003] At the same time, the flat wire hairpin winding scheme in the industry generally uses an even number of layers (4, 6, 8 layers). Due to the problems of complex and changeable arrangement of odd layers and greater difficulty in branch symmetry, there are very few motors with odd layers on the market. In addition, the industry currently provides a variety of single-layer flat wire winding schemes, which have a single arrangement. At the same time, the conductors of each parallel branch are distributed in different positions of the stator slot, resulting in the phenomenon that the branch is not strictly symmetrical, leading to differences in back electromotive force, resistance, and inductance, thereby forming a circulating current, increasing additional losses and reducing efficiency, and causing local overheating of the motor winding, affecting the service life of the motor. In addition, the winding arrangement and connection method in the odd-layer hairpin motor is one of the difficulties in the design of this type of motor.

[0004] At present, patent CN111478477A discloses a motor stator and a motor, wherein the winding method of the odd-layer flat wire winding has 5 layers of flat wire, but actually needs to add an extra layer to extend to the 6th layer for welding, which increases the outer diameter of the winding, resulting in a reduction in the electrical clearance between the outer diameter of the winding and the inner diameter of the casing, bringing about a safety hazard to electrical insulation.

[0005] At the same time, the existing technology has the following problems:

[0006] 1. There are many types of coils in the odd-numbered hairpin winding scheme, and the arrangement is complex; many bus bars and busbars are required to connect the branches and center points of each phase winding, which increases the height of the winding end and reduces the motor efficiency;

[0007] 2. In order to balance the potential of each branch in the winding, odd-numbered windings use more special-shaped coils. The existence of special-shaped coils will increase the difficulty of coil manufacturing and is not conducive to mass production;

[0008] 3. The odd-numbered windings have the problem of asymmetric winding branches, which leads to differences in back electromotive force, resistance, inductance, etc., resulting in reduced motor performance and winding circulation, increased motor additional losses, and easy to cause local overheating of the motor.

[0009] Therefore, we propose an odd-layer flat wire motor stator and winding structure to solve the above problems. Summary of the invention

[0010] In order to overcome the above defects of the prior art, an embodiment of the present invention provides an odd-layer flat wire motor stator and winding structure to solve the problems raised in the above background technology.

[0011] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an odd-layer flat wire motor stator and winding structure, comprising a stator core, wherein the stator core is formed by stacking a plurality of silicon steel sheets, and a plurality of rectangular slots of the same size are opened on the stator core in a circular array, and a plurality of conductors are inserted into the plurality of rectangular slots.

[0012] In a preferred embodiment, one end of the conductor is connected by a hairpin, and the other end of the conductor is formed into a welding end by twisting and expanding the conductor.

[0013] In a preferred embodiment, a plurality of silicon steel sheets can be stacked and connected together by riveting, welding or bonding.

[0014] In a preferred embodiment, the plurality of rectangular grooves are filled with insulating paper, and the thickness of the insulating paper is between 0.15 mm and 0.55 mm.

[0015] In a preferred embodiment, the number of conductors inserted into the plurality of rectangular slots is 2n+1, where n is a natural number.

[0016] In a preferred embodiment, the conductors in the plurality of rectangular slots are electrically connected, and the conductors in the rectangular slots are positioned and fixed by hairpins or welding to form a stator winding.

[0017] In a preferred embodiment, the stator windings in the plurality of rectangular slots have one or three parallel branches, which are distributed in a stator circumferential direction.

[0018] Technical effects and advantages of the present invention:

[0019] 1. The present invention breaks through the constraint that the existing flat wire motor can only have an even number of layers, so that the choice of the number of layers in the design of the flat wire motor is no longer limited, and direct welding of odd-numbered layers is realized, without the need to add an additional expansion layer for welding, and will not cause insulation hazards caused by the reduction of the electrical gap.

[0020] 2. The stator is arranged in an odd number of coils and a composite distributed winding arrangement, so that there is a phase difference between the magnetomotive forces generated by the coils of each phase. The magnetomotive forces are superimposed on each other, and the magnetomotive forces after superposition are smaller than the magnetomotive forces overlapped in the prior art, thereby enabling the motor to weaken the harmonics generated by the motor to a certain extent, especially the 5th and 7th harmonics, and to reduce torque pulsation and noise, thereby improving motor performance.

[0021] Summary: This patent takes 54-slot 5-layer coils as an example and introduces a patent for an odd-numbered H-pin winding in which each layer of the coils has 5, 7, etc. The odd-numbered layer flat wire winding scheme is compatible with 1-way and 3-way motor flat wire schemes. The stator is arranged with an odd number of coils and a composite distributed winding arrangement so that there is a phase difference between the magnetic motive forces generated by the coils of each phase. The magnetic motive forces are superimposed on each other, and the superimposed magnetic motive forces are smaller than the magnetic motive forces overlapped in the prior art, thereby enabling the motor to weaken the harmonics generated by the motor to a certain extent, especially to significantly weaken the 5th and 7th harmonics, and to reduce torque pulsation and noise, thereby improving motor performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the structure of the winding coil of the entire flat wire motor in the present invention;

[0023] Figure 2 It is a planar development schematic diagram of the stator winding in the present invention;

[0024] Figure 3 It is a partial enlarged schematic diagram of a plane expansion of the stator winding in the present invention;

[0025] Figure 4 It is a partial schematic diagram of the cross-sectional structure of the stator in the present invention.

[0026] The reference numerals in the drawings are: 1. stator core; 2. insulating paper; 3. hairpin; 4. welding end; 5. three-phase input and output wires; 6. rectangular slot; 7. conductor. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Embodiment 1

[0029] Reference Figure 1-4, an odd-layer flat wire motor stator and winding structure, including a stator core 1, the stator core 1 is formed by stacking a plurality of silicon steel sheets, a plurality of rectangular slots 6 of the same size are opened on the stator core 1 in a circumferential array, and a plurality of conductors 7 are inserted into the plurality of rectangular slots 6; one end of the conductor is connected by a hairpin 3, and the other end of the conductor 7 is formed by twisting and expanding the welding end 4; the plurality of silicon steel sheets can be stacked and connected together by riveting, welding or bonding; 54 rectangular slots 6 are each provided with insulating paper 2, and the thickness of the insulating paper 2 is between 0.15 mm and 0.55 mm; the number of conductors 7 inserted into the plurality of rectangular slots 6 is 2n+1, where n is a natural number, the conductors 7 in the plurality of rectangular slots 6 are electrically connected, and the conductors 7 in the rectangular slots 6 are positioned and fixed by hairpins 3 or welding to form a stator winding, and the number of parallel branches of the stator winding in the plurality of rectangular slots 6 is one or three, and they are distributed in a stator circumferential direction.

[0030] Embodiment 2

[0031] Reference Figure 1 , Figure 4 The invention discloses an odd-layer flat wire motor stator and winding structure. The stator core 1 is formed by stacking a certain number of silicon steel sheets, which can be riveted, welded or bonded in various ways. 54 rectangular slots 6 of the same size are opened in a circular array on the stator core 1. Considering insulation, an insulating paper 2 of a certain thickness is inserted into the rectangle 6. A flat copper conductor 7 is inserted into the 54 rectangular slots 6. 2n+1 conductors can be inserted into each slot, where n is a natural number. In order to realize electrical connection between the conductors in the 54 rectangular slots 6, a hairpin or welding method is required. The 54-slot stator winding has 1 or 3 parallel branches, which are distributed according to the span rule in a stator circumferential direction.

[0032] Assuming that 2n+1 conductors can be inserted into each rectangular slot 6, there are 2n layers of conductors in each rectangular slot 6, and it is stated that the layer close to the bottom of the stator slot is the outer layer, and the layer close to the stator slot mouth is the inner layer. The conductors in the slots corresponding to each branch are installed in the rectangular slot 6 with the span regularity in a cycle according to adjacent layers, until a circle is completed and switched to the next pair of adjacent layers for cyclic installation arrangement; in particular, the three-phase input and output lines 5 of the flat wire motor stator are arranged in the outermost and innermost layers of the rectangular slot 6; in particular, in the reversing connection of each branch, a number of hairpin coils with reversed heads are used for electrical bridging, and these hairpin coils with reversed heads are located in the innermost and outermost layers of the rectangular slot 6.

[0033] Embodiment 3

[0034] Reference Figure 1 , Figure 4, an odd-number-layer flat wire motor stator and winding structure, a plurality of silicon steel sheets are laminated into a flat wire motor stator core 1, which comprises a stator yoke, a stator tooth and a stator tooth head, 54 stator slots are formed by the three parts of the stator core 1, and the stator slots are rectangular slots 6. Considering insulation, an insulating paper 2 of a certain length and thickness is inserted into each stator slot;

[0035] Reference Figure 1 , Figure 4 , an odd-layer flat wire motor stator and winding structure, the winding coil of the entire flat wire motor, which includes a straight segment conductor inserted into the stator core slot, the straight segment conductor at one end of the core is connected by a U-shaped hairpin, and the straight segment conductor at the other end can be formed by twisting and expanding the welding method to form a welding end (4);

[0036] There are 6 lead wires in total for the three-phase lead wires and the neutral point, which are located on the outermost layer of the stator core.

[0037] Embodiment 4

[0038] Reference Figure 2 , Figure 3 , an odd-layer flat wire motor stator and winding structure, the current flows from the first layer (second slot) A1+:

[0039] Passing through the first and second layers of a (the 10th slot): issuing cards across 8 - issuing cards across 9 - issuing cards across 8 - issuing cards across 9 - issuing cards across 11 - issuing cards across 9;

[0040] a The first and second layers (slot 11): card issuance across 8 - card issuance across 9 - card issuance across 11 - card issuance across 9 - card issuance across 8 - card issuance across 9;

[0041] a The first and second layers (slot 12): card issuance across 11 - card issuance across 9 - card issuance across 8 - card issuance across 11 - card issuance across 9 - card issuance across 8;

[0042] Flow direction: b. The third and fourth layers (the 10th slot): card issuance across span 8 - card issuance across span 9 - card issuance across span 8 - card issuance across span 9 - card issuance across span 11 - card issuance across span 9;

[0043] b The third and fourth layers (slot 11): card issuance across 8 - card issuance across 9 - card issuance across 11 - card issuance across 9 - card issuance across 8 - card issuance across 9;

[0044] b The third and fourth layers (slot 12): card issuance across 11 - card issuance across 9 - card issuance across 8 - card issuance across 11 - card issuance across 9 - card issuance across 8;

[0045] Flow direction: c fifth layer (10th slot): card issuance across 8 - card issuance across 9 - card issuance across 8 - card issuance across 9 - card issuance across 11 - card issuance across 9;

[0046] c The fifth layer (the 11th slot): card issuance across 8 - card issuance across 9 - card issuance across 11 - card issuance across 9 - card issuance across 8 - card issuance across 9;

[0047] c The fifth layer (the 12th slot): card issuance across 11 - card issuance across 9 - card issuance across 8 - card issuance across 8 - card issuance across 9 - card issuance across 8;

[0048] Flow direction: d43rd layer (slot 28): card issuance across span 11 - card issuance across span 8 - card issuance across span 10 - card issuance across span 8 - card issuance across span 9 - card issuance across span 8;

[0049] d The fourth third layer (slot 29): card issuance across 8 - card issuance across 9 - card issuance across 11 - card issuance across 9 - card issuance across 8 - card issuance across 9;

[0050] d The fourth and third layer (slot 30): card issuance across 8 - card issuance across 9 - card issuance across 8 - card issuance across 9 - card issuance across 11 - card issuance across 9;

[0051] Flow direction: e2nd layer (slot 28): card issuance across span 11 - card issuance across span 8 - card issuance across span 10 - card issuance across span 8 - card issuance across span 9 - card issuance across span 8;

[0052] The second layer of e-wine (slot 29): card issuance across 8 - card issuance across 9 - card issuance across 11 - card issuance across 9 - card issuance across 8 - card issuance across 9;

[0053] eThe second layer (slot 30): card issuance across 8 - card issuance across 9 - card issuance across 8 - card issuance across 9 - card issuance across 11 - card issuance across 9;

[0054] Finally, it flows out from the first layer (slots 19, 20, and 21) A1-, A2-, and A3-.

[0055] Embodiment 5

[0056] Reference Figure 1-Figure 4 , an odd-layer flat wire motor stator and winding structure, the assembly steps are as follows:

[0057] Step 1 (inserting insulating paper 2): first place the stator core 1 on the paper inserting machine, then the equipment folds the roll paper into a slot shape, and pushes the folded insulating paper 2 into the rectangular slot 6 where the stator core 1 is located in sequence, until all the insulating paper 2 in the 54 rectangular slots 6 are pushed into place;

[0058] Step 2 (Insert the first and second layer U hairpins): Place the stator core with the insulating paper inserted on the device for inserting hairpin 3, and then insert span 8 hairpin - span 9 hairpin - span 8 hairpin - span 9 hairpin - span 11 hairpin - span 9 hairpin respectively. After the first and second layer hairpins are inserted, insert the second layer span 11 hairpin - span 8 hairpin - span 10 hairpin - span 8 hairpin - span 9 hairpin - span 8 hairpin. So far, all 54 hairpins in the first and second layers have been inserted;

[0059] Step 3 (Insert the third and fourth layers of U hairpins): Then insert the third and fourth layers of hairpins in sequence along the circumferential direction of the stator core 1, including span 8 hairpins - span 9 hairpins - span 8 hairpins - span 9 hairpins - span 11 hairpins - span 9 hairpins, and then insert the fourth and third layers of hairpins respectively. So far, a total of 54 hairpins in the third and fourth layers have been inserted;

[0060] Step 4 (Insert the fifth layer U hair cards): Finally, insert 6 span 8 hair cards, 6 span 9 hair cards, and 6 span 8 hair cards in the fifth layer, and continue to insert 3 span 9 hair cards and 3 span 11 hair cards in sequence; now all 27 hair cards in the fifth layer have been inserted;

[0061] Step 5 (expansion and twisting): insert the flat wire stator with the insulating paper 2 and the U-shaped hairpin 3, place it on the expansion and twisting machine, first expand the fifth layer of hairpin pins to the specified position, then expand the third and fourth layers of hairpin pins to the specified position, and finally expand the first and second layers of hairpin pins to the specified position; then push all the hairpin pins into the twisting die slot, and finally rotate the second, third, fourth, and fifth layers of twisting dies in the opposite direction along the circumferential direction by 26.667° at the same time, and the entire stator end is twisted;

[0062] Step 6 (head cutting): The flat wire stator with the twisted head is cut as a whole. After the head cutting is completed, the height of the pins at the end is flush and consistent;

[0063] Step 7 (welding): The cut flat wire stator is placed on the welding machine for welding.

[0064] Finally, a few points should be explained: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, which may refer to mechanical connection or electrical connection, or internal communication between two components, or direct connection. "upper", "lower", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may change;

[0065] Secondly: In the drawings of the embodiments disclosed in the present invention, only the structures related to the embodiments disclosed in the present invention are involved, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other;

[0066] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An odd-number-layer flat wire motor stator, comprising a stator core (1), characterized in that: The stator core (1) is formed by laminating a plurality of silicon steel sheets, and a plurality of rectangular slots (6) of the same size are provided on the stator core (1) in a circumferential array, and a plurality of conductors (7) are inserted into each of the plurality of rectangular slots (6).

2. The odd-layer flat wire motor stator according to claim 1, characterized in that: One end of the conductor is connected by a hairpin (3), and the other end of the conductor (7) is welded by twisting and expanding the conductor to form a welding end (4).

3. The odd-layer flat wire motor stator according to claim 1, characterized in that: Multiple silicon steel sheets can be stacked and connected together by riveting, welding or bonding.

4. The odd-layer flat wire motor stator according to claim 3, characterized in that: Insulating paper (2) is contained in each of the 54 rectangular grooves (6), and the thickness of the insulating paper (2) is between 0.15 mm and 0.55 mm.

5. The stator and winding structure of an odd-number-layer flat wire motor according to claim 4, characterized in that: The number of conductors (7) inserted into the plurality of rectangular slots (6) is 2n+1, where n is a natural number.

6. The stator and winding structure of an odd-number-layer flat wire motor according to claim 5, characterized in that: The conductors (7) in the plurality of rectangular slots (6) are electrically connected, and the conductors (7) in the rectangular slots (6) are positioned and fixed by means of hairpins (3) or welding to form a stator winding.

7. The stator and winding structure of an odd-number-layer flat wire motor according to claim 6, characterized in that: The stator windings in the plurality of rectangular slots (6) have one or three parallel branches, which are distributed in a stator circumferential direction.

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