A stator assembly with low slot voltage drop and a motor

Abstract

The present invention belongs to the technical field of motors, and particularly relates to a low slot voltage drop stator assembly and a motor. The stator assembly includes a stator core and a stator winding; the stator winding is provided with an even number of pole pairs greater than or equal to 2; and each phase winding is provided with two branches, the heads of the two branches are located within the same pole, and the windings of the two branches extend in opposite directions on the circumference of the stator core; each branch passes through M stator slots. By changing the outlet positions of the first and last ends of the lap winding on the stator core and making the windings of the two branches extend in opposite directions on the circumference of the stator core, the present invention can avoid the head of one branch and the end of the other branch being in the same stator slot, effectively reducing the maximum slot voltage drop of the stator winding. Moreover, the more the number of pole pairs, the more obvious the decrease in the slot voltage drop. In this way, the insulation reliability of the stator winding in the stator slot is improved, creating conditions for reducing the insulation thickness of the enameled wire.

Description

Technical Field

[0001] The present invention belongs to the technical field of motors, and particularly relates to a stator assembly with low slot voltage drop and a motor. Background Art

[0002] In existing flat wire motor solutions, the components where the leading and trailing ends of many motor windings are led out are located in the same stator slot. Therefore, the wires between different layers in this stator slot bear the voltage drop of the entire phase winding. As the working voltage gets higher and higher, the voltage drop between the wires in these special stator slots also becomes larger and larger, and the insulation withstand voltage ability of the enameled wire is increasingly challenged. Many designs have no choice but to increase the film thickness of the enameled wire. On the one hand, this increases the production difficulty of the enameled wire, and on the other hand, it reduces the cross-sectional area of the copper wire in the slot and increases the thermal resistance of the wires in the slot. Summary of the Invention

[0003] In view of the above problems, the present invention provides a stator assembly with low slot voltage drop. The stator assembly includes a stator core and a stator winding; a plurality of stator slots are arranged on the stator core along its circumferential direction; the winding of the stator winding uses rectangular wires and is arranged in a lap winding form; a plurality of wire layers are arranged radially along the stator core in the stator slot, and each wire layer is provided with a rectangular wire.

[0004] The stator winding is provided with an even number of pole pairs greater than or equal to 2; and each phase winding is provided with two branches. The leading ends of the two branches are located in the same pole, and the winding directions of the two branches along the circumference of the stator core are opposite; each branch passes through M stator slots, where M = P / A / B, P is the total number of stator slots on the stator core, A is the number of phases of the stator winding, and B is the number of branches under the same phase winding.

[0005] Further, in the same phase winding, the leading ends of the two branches are located in the same stator slot.

[0006] Further, in the same phase winding, the trailing ends of the two branches are respectively located at the same slot positions in two poles, and there is one pole interval between these two poles.

[0007] Further, the leading end and the trailing end of the branch refer to the rectangular wires at both ends of the branch winding located in the stator slot.

[0008] Further, in each phase winding of the stator winding, the lead wires connected to the trailing ends of each branch are all turned 180° and concentrated in one direction.

[0009] The present invention also provides a motor with low slot voltage drop, including the above stator assembly.

[0010] The beneficial effects of the present invention are as follows: By changing the outlet positions of the start and end of the lap winding on the stator core and making the winding extension directions of the two branches opposite on the circumference of the stator core, it can be avoided that the start of one branch and the end of the other branch are in the same stator slot, effectively reducing the maximum slot voltage drop of the stator winding. Moreover, the more the number of pole pairs, the more obvious the decrease in the slot voltage drop. In this way, the insulation reliability of the stator winding in the stator slot is improved, creating conditions for reducing the insulation thickness of the enameled wire. In addition, the number of stator slots passed by each branch is the same, achieving a balanced circuit state.

[0011] Other features and advantages of the present invention will be described in the subsequent description, and in part, will be obvious from the description or will be understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures pointed out in the description, claims, and drawings. Brief Description of the Drawings

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0013] Figure 1 Shows a partial cross-sectional schematic diagram of the stator core in the embodiment of the present invention;

[0014] Figure 2 Shows a schematic diagram of the winding path of one phase with two branches in Embodiment 1 of the present invention;

[0015] Figure 3 Shows a schematic diagram of the winding path of one phase with two branches in Embodiment 2 of the present invention; In the figure:

[0016] Figure 4 Shows a schematic diagram of the winding path of one phase with two branches in Embodiment 3 of the present invention;

[0017] Figure 5 Shows a schematic diagram of the winding path of one phase with two branches in Embodiment 4 of the present invention. Detailed Embodiments

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0019] An embodiment of the present invention provides a low slot voltage drop motor, and the motor includes a stator assembly.

[0020] The stator assembly includes a stator core and a stator winding. As Figure 1 shown, a plurality of stator slots are provided on the stator core along its circumferential direction. The winding of the stator winding uses rectangular wires, and the winding is arranged in a lap winding form. A plurality of wire layers are arranged radially along the stator core in the stator slots, and each wire layer is provided with a rectangular wire to form the in-slot winding of the stator winding.

[0021] The stator winding is provided with an even number of pole pairs greater than or equal to 2; and each phase winding is provided with two branches, the heads of the two branches are located within the same pole, and the windings of the two branches extend in opposite directions on the circumference of the stator core; each branch passes through M stator slots, where M = P / A / B, P is the total number of stator slots on the stator core, A is the number of phases of the stator winding, and B is the number of branches under the same phase winding.

[0022] The present invention changes the outlet positions of the heads and tails of the lap winding on the stator core, and makes the windings of the two branches extend in opposite directions on the circumference of the stator core. In this way, it can be avoided that the head of one branch and the tail of the other branch are in the same stator slot, effectively reducing the highest slot voltage drop of the stator winding, and the more the number of pole pairs, the more obvious the decrease in the slot voltage drop. Thus, the insulation reliability of the stator winding in the stator slot is improved, creating conditions for reducing the insulation thickness of the enameled wire. In addition, the number of stator slots passed by each branch is the same, achieving a balanced circuit state.

[0023] It should be noted that the stator winding can be divided into an in-slot winding and an end winding; the in-slot winding refers to the part of the rectangular conductor in the stator slot, and the end winding refers to the part of the rectangular wire on both sides of the stator core. The function of the end winding is to connect the rectangular wires at different positions in different stator slots in pairs according to a certain span to realize the internal connection of the stator winding. The heads and tails of the above branches refer to the rectangular wires at both ends of the branch windings in the stator slots.

[0024] Preferably, in the same-phase winding, the heads of two branches are located in the same stator slot. Such a design can further reduce the maximum slot voltage drop of the stator winding on the one hand, and make the three-phase lead-out wires of the motor most convenient to lead out on the other hand.

[0025] Further preferably, in the same-phase winding, the ends of two branches are located at the same slot positions of two poles, and there is one pole interval between these two poles. This setting method can further reduce the maximum slot voltage drop of the stator slot.

[0026] It should be noted that, for the same-phase winding, multiple stator slots located in the same pole are defined as the slot positions of this pole.

[0027] For example, if there are two stator slots in the same pole under the same-phase winding, then these two stator slots are respectively defined as slot position Q1 and slot position Q2. In the same stator assembly, the definition direction of slot positions is the same.

[0028] Preferably, in each phase winding of the stator winding, the lead-out wires connected to the ends of each branch all concentrate in one direction. This creates conditions for connecting all neutral point wires with one copper bar.

[0029] It should be noted that the head and end of the above branch can be defined by exchanging each other.

[0030] For the convenience of description, as Figures 2 - 4 shown, along the circumferential direction of the stator core, the stator slots are sequentially numbered as 1, 2, 3,..., N, where N is the number of stator slots on the stator core.

[0031] Along the direction from the outside to the center of the stator core, the rectangular wires in the same stator slot are sequentially numbered as 1, 2, 3,..., n. Where n is the number of rectangular conductors in a single stator slot; the 1st rectangular wire is close to the outside of the stator core, and the nth wire is close to the center of the stator core.

[0032] N(n) represents the nth layer of wire in the Nth stator slot. For example: 1(1) represents the 1st layer of wire in the 1st stator slot. 24(6) represents the 6th layer of wire in the 24th stator slot.

[0033] Embodiment 1

[0034] As Figure 2 shown, there are 48 stator slots on the stator core, and 6 layers of rectangular wires are arranged in each stator slot; there are 4 pairs of poles, that is, 8 poles, on the stator winding.

[0035] One of the phase windings includes branch one and branch two. The specific connection path of branch one is: starting end 1(1) → 43(2) → 1(3) → 43(4) → 1(5) → 43(6) → 37(6) → 43(5) → 37(4) → 43(3) → 37(2) → 43(1) → 2(1) → 44(2) → 2(3) → 44(4) → 2(5) → 44(6) → 38(6) → 44(5) → 38(4) → 44(3) → 38(2) → 44(1) → 37(1) → 31(2) → 37(3) → 31(4) → 37(5) → 31(6) → 25(6) → 31(5) → 25(4) → 31(3) → 25(2) → 31(1) → 38(1) → 32(2) → 38(3) 32(4) → 38(5) → 32(6) → 26(6) → 32(5) → 26(4) → 32(3) → 26(2) → 32(1) ending end.

[0036] The specific connection path of branch two is: starting end 2(6) → 8(5) → 2(4) → 8(3) → 2(2) → 8(1) → 14(1) → 8(2) → 14(3) → 8(4) → 14(5) → 8(6) → 1(6) → 7(5) → 1(4) → 7(3) → 1(2) → 7(1) → 13(1) → 7(2) → 13(3) → 7(4) → 13(5) → 7(6) → 14(6) → 20(5) → 14(4) → 20(3) → 14(2) → 20(1) → 26(1) → 20(2) → 26(3) → 20(4) → 26(5) → 20(6) → 13(6) → 19(5) → 13(4) → 19(3) → 13(2) → 19(1) → 25(1) → 19(2) → 25(3) → 19(4) → 25(5) → 19(6) ending end.

[0037] As Figure 2 shown, the rectangular conductors corresponding to the starting ends of the two branches are respectively in the 1st stator slot and the 2nd stator slot, and the 1st stator slot and the 2nd stator slot belong to the same pole. In this embodiment, the 1st stator slot, the 2nd stator slot, the 25th stator slot and the 26th stator slot are the common stator slots of the two branches. The voltages at the starting ends of the two branches, that is, the voltage in the 1st stator slot and the voltage in the 2nd stator slot, are the highest slot voltage drops in the stator winding, equal to 1 / 3 phase voltage; the voltages at the ending ends of the two branches, that is, the voltage in the 25th stator slot and the voltage in the 26th stator slot, are also close to 1 / 3 phase voltage. Therefore, in this embodiment, the highest slot voltage drop is significantly reduced.

[0038] Embodiment Two

[0039] As Figure 3As shown, in the first embodiment, 48 stator slots are provided on the stator core, and 6 layers of rectangular wires are provided in each stator slot; 4 pairs of poles, that is, 8 poles, are provided on the stator winding.

[0040] One phase winding includes branch one and branch two. The specific connection path of branch one is: head end 1(1) → 43(2) → 1(3) → 43(4) → 1(5) → 43(6) → 37(6) → 43(5) → 37(4) → 43(3) → 37(2) → 43(1) → 2(1) → 44(2) → 2(3) → 44(4) → 2(5) → 44(6) → 38(6) → 44(5) → 38(4) → 44(3) → 38(2) → 44(1) → 37(1) → 31(2) → 37(3) → 31(4) → 37(5) → 31(6) → 25(6) → 31(5) → 25(4) → 31(3) → 25(2) → 31(1) → 38(1) → 32(2) → 38(3) 32(4) → 38(5) → 32(6) → 26(6) → 32(5) → 26(4) → 32(3) → 26(2) → 32(1) end.

[0041] The specific connection path of branch two is: head end 1(6) → 7(5) → 1(4) → 7(3) → 1(2) → 7(1) → 14(1) → 8(2) → 14(3) → 8(4) → 14(5) → 8(6) → 2(6) → 8(5) → 2(4) → 8(3) → 2(2) → 8(1) → 13(1) → 7(2) → 13(3) → 7(4) → 13(5) → 7(6) → 13(6) → 19(5) → 13(4) → 19(3) → 13(2) → 19(1) → 26(1) → 20(2) → 26(3) → 20(4) → 26(5) → 20(6) → 14(6) → 20(5) → 14(4) → 20(3) → 14(2) → 20(1) → 25(1) → 19(2) → 25(3) → 19(4) → 25(5) → 19(6) end.

[0042] As Figure 3 shown, the rectangular conductors corresponding to the head ends of the two branches are both in the No. 1 stator slot. In this embodiment, the No. 1 stator slot, the No. 2 stator slot, the No. 25 stator slot and the No. 26 stator slot are the common stator slots of the two branches. The highest slot voltage drops in both branches are located in the stator slots where the branch ends are located, that is, the voltages in the No. 25 stator slot and the No. 26 stator slot are both close to 1 / 3 phase voltage; while in the stator slot where the head ends of the two branches are located, that is, in the No. 1 stator slot, the highest voltage is 1 / 12 phase voltage.

[0043] Compared with the first embodiment, the highest slot voltage is further reduced in the stator assembly of this embodiment.

[0044] Embodiment Three

[0045] As Figure 4 shown, in the third embodiment, 72 stator slots are provided on the stator core, and 6 layers of rectangular wires are provided in each stator slot; 4 pairs of poles, i.e., 8 poles, are provided on the stator winding.

[0046] One phase winding includes branch one and branch two. The specific connection path of branch one is: starting end 1(1) → 10(2) → 1(3) → 10(4) → 1(5) → 10(6) → 19(6) → 10(5) → 19(4) → 10(3) → 19(2) → 10(1) → 2(1) → 11(2) → 2(3) → 11(4) → 2(5) → 11(6) → 20(6) → 11(5) → 20(4) → 11(3) → 20(2) → 11(1) → 3(1) → 12(2) → 3(3) → 12(4) → 3(5) → 12(6) → 21(6) → 12(5) → 21(4) → 12(3) → 21(2) → 12(1) → 19(1) → 28(2) → 19(3) → 28(4) → 19(5) → 28(6) → 37(6) → 28(5) → 37(4) → 28(3) → 37(2) → 28(1) → 20(1) → 29(2) → 20(3) → 29(4) → 20(5) → 29(6) → 38(6) → 29(5) → 38(4) → 29(3) → 38(2) → 29(1) → 21(1) → 30(2) → 21(3) → 30(4) → 21(5) → 30(6) → 39(6) → 30(5) → 39(4) → 30(3) → 39(2) → 30(1) ending end.

[0047] The specific connection path of Branch Two is as follows: the head end 1(6) → 64(5) → 1(4) → 64(3) → 1(2) → 64(1) → 56(1) → 65(2) → 56(3) → 65(4) → 56(5) → 65(6) → 2(6) → 65(5) → 2(4) → 65(3) → 2(2) → 65(1) → 57(1) → 66(2) → 57(3) → 66(4) → 57(5) → 66(6) → 3(6) → 66(5) → 3(4) → 66(3) → 3(2) → 66(1) → 55(1) → 64(2) → 55(3) → 64(4) → 55(5) → 64(6) → 55(6) → 46(5) → 55(4) → 46(3) → 55(2) → 46(1) → 38(1) → 47(2) → 38(3) → 47(4) → 38(5) → 47(6) → 56(6) → 47(5) → 56(4) → 47(3) → 56(2) → 47(1) → 39(1) → 48(2) → 39(3) → 48(4) → 39(5) → 48(6) → 57(6) → 48(5) → 57(4) → 48(3) → 57(2) → 48(1) → 37(1) → 46(2) → 37(3) → 46(4) → 37(5) → 46(6) the end.

[0048] As Figure 4 shown, the head ends of the two branches are in the same stator slot, which are the first-layer rectangular wire in the 1st stator slot and the sixth-layer rectangular wire in the 1st stator slot respectively. In this embodiment, the 1st stator slot, the 2nd stator slot, the 3rd stator slot, the 37th stator slot, the 38th stator slot and the 39th stator slot are the common stator slots of the two branches. The highest slot voltage drops in the two branches are located in the 37th stator slot and the 26th stator slot respectively, and their values are about 1 / 3 of the phase voltage. In this embodiment, the stator assembly achieves the effect of effectively reducing the slot voltage drop.

[0049] Embodiment Four

[0050] This embodiment is based on the above Embodiment Three, and the connection path of Branch Two is changed, as Figure 5As shown, the specific connection path of Branch Two is: the head end 1(6) → 64(5) → 1(4) → 64(3) → 1(2) → 64(1) → 56(1) → 65(2) → 56(3) → 65(4) → 56(5) → 65(6) → 2(6) → 65(5) → 2(4) → 65(3) → 2(2) → 65(1) → 57(1) → 66(2) → 57(3) → 66(4) → 57(5) → 66(6) → 3(6) → 66(5) → 3(4) → 66(3) → 3(2) → 66(1) → 55(1) → 64(2) → 55(3) → 64(4) → 55(5) → 64(6) → 55(6) → 46(5) → 55(4) → 46(3) → 55(2) → 46(1) → 37(1) → 46(2) → 37(3) → 46(4) → 37(5) → 46(6) → 56(6) → 56(6) → 47(5) → 56(4) → 47(3) → 56(2) → 47(1) → 38(1) → 47(2) → 38(3) → 47(4) → 38(5) → 47(6) → 57(6) → 48(5) → 57(4) → 48(3) → 57(2) → 48(1) → 39(1) → 48(2) → 39(3) → 48(4) → 39(5) → 48(6) the end.

[0051] In this embodiment, the head ends of the two branches are in the same stator slot, which is the 1st stator slot; the end of the two branches are respectively located in the 30th stator slot and the 48th stator slot. The 30th stator slot and the 48th stator slot belong to the same slot positions of two poles, and there is another pole between these two poles, and the connection order of the slot positions of the two branches is the same. The highest slot voltage drop in the branch is reduced to 1 / 6 of the phase voltage, which is located in the 38th stator slot.

[0052] Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A stator assembly with low slot voltage drop, characterized in that, the stator assembly includes a stator core and a stator winding; a plurality of stator slots are arranged on the stator core along its circumferential direction; the winding of the stator winding uses rectangular wires and is arranged in a lap winding form; several layers of wire layers are arranged radially in the stator slots along the stator core, and one rectangular wire is arranged in each wire layer; the stator winding is provided with an even number of pole pairs greater than or equal to 2; and each phase winding is provided with two branches, the heads of the two branches are located within the same pole, and the windings of the two branches extend in opposite directions on the circumference of the stator core; each branch passes through M stator slots, where M = P / A / B, P is the total number of stator slots on the stator core, A is the number of phases of the stator winding, and B is the number of branches under the same phase winding.

2. A stator assembly with low slot voltage drop according to claim 1, characterized in that, in the same phase winding, the heads of the two branches are located in the same stator slot.

3. A stator assembly with low slot voltage drop according to claim 1 or 2, characterized in that, in the same phase winding, the ends of the two branches are respectively located at the same slot positions of two poles, and there is one pole interval between these two poles.

4. A stator assembly with low slot voltage drop according to claim 3, characterized in that, the head and the end of the branch refer to the rectangular wires at both ends of the branch winding located in the stator slot.

5. A stator assembly with low slot voltage drop according to claim 1, characterized in that, in each phase winding of the stator winding, the lead wires connected to the ends of each branch are all turned 180° and concentrated in one direction.

6. A low-slot-voltage-drop motor, characterized in that, the motor includes any one of the stator assemblies in claims 1-5.

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