Motor stators, flat wire motors, powertrains and power units

Abstract

The present application provides a motor stator, a flat-wire motor, a powertrain, and a power device. The motor stator includes a stator core and a stator winding. The stator winding includes N / 2 coil groups, each of which includes multiple hairpin coils. The first and second plug-in portions of each hairpin coil are respectively inserted into different stator slots to form a flat-wire conductor. The first and second plug-in portions of each hairpin coil in the kth coil group are respectively inserted into the 2k-1th and 2kth layers of flat-wire conductors of adjacent pole phases. Each phase winding includes two parallel branches. This connection method can simplify the busbar structure of the motor stator, thereby reducing the axial size of the flat-wire motor.

Description

Technical Field

[0001] The present application relates to the field of motors, and in particular to a motor stator, a flat wire motor, a power assembly, and a power device. Background Art

[0002] Flat wire motors, with their high copper fill rate, facilitate heat dissipation from the motor windings, improve the winding's voltage resistance, and reduce winding end length, thereby increasing the motor's torque and power density. Therefore, flat wire motors have become a key measure in promoting vehicle lightweighting, increasing electric vehicle range, improving vehicle space utilization, and reducing powertrain costs.

[0003] Existing motors mainly use a winding structure of wave winding or stacked winding. By designing the flat wire conductors in the winding structure into multiple layers, the AC resistance of the motor can be effectively reduced. However, as the number of layers of flat wire conductors increases, the wiring method of the winding structure becomes more complicated, and there are usually multiple parallel branches in the winding structure. In the parallel branches of the existing winding structure, the incoming and outgoing wires of different parallel branches are usually connected to different layers of flat wire conductors in different slots. For example, the incoming and outgoing wires of each parallel branch are respectively led out from the inner and outer flat wire conductors of the stator slots. The busbar structure at the busbar end needs to be provided with conductive bars of different heights on both sides to respectively connect the flat wire conductors of different layers, which usually leads to the use of complex busbar structures and a variety of special-shaped connecting wires. At the same time, the use of a multi-layer busbar structure will also increase the size of the entire stator in the axial direction, which is not conducive to reducing the size of the motor. Summary of the Invention

[0004] The present application provides a motor stator, a flat wire motor, a power assembly and a power device to simplify the busbar structure of the motor stator and reduce the axial size of the busbar structure at the bus end of the motor stator, thereby facilitating the reduction in size of the flat wire motor.

[0005] In a first aspect, the present application provides a motor stator, which includes a stator core and a stator winding, wherein the stator core includes Z stator slots, each stator slot is provided with N layers of flat wire conductors, N is an even number ≥2; the stator winding includes m-phase windings, each phase winding includes two parallel branches, the number of magnetic poles of the stator winding is 2p, p is an integer, the stator winding includes N / 2 coil groups, and the N / 2 coil groups form an m-phase winding; any coil group includes three types of hairpin coils with spans of Z / (2p)-1, Z / (2p) and Z / (2p)+1, and any hairpin coil includes The first plug-in portion and the second plug-in portion are connected to each other, and the first plug-in portion and the second plug-in portion of any hairpin coil are respectively inserted in different stator slots to form a flat wire conductor. The first plug-in portion and the second plug-in portion of each hairpin coil of the kth coil group are respectively inserted in the 2k-1 layer of flat wire conductor and the 2k layer of flat wire conductor of the adjacent pole phase, k is an integer ranging from 1 to N / 2, the hairpin coil with a span of Z / (2p)-1 and the hairpin coil with a span of Z / (2p)+1 are located in the same pole phase group, and the hairpin coils in any coil group are evenly distributed in the parallel branches of each phase winding.

[0006] In the motor stator of the present application, the stator winding includes multiple coil groups, and according to the number of layers of flat wire conductors, starting from the first layer of flat wire conductors, every two adjacent layers of flat wire conductors form a coil group, and the two plug-in parts of each hairpin coil in any coil group, namely the first plug-in part and the second plug-in part, are respectively inserted into the stator slots of adjacent pole phases to form flat wire conductors, wherein any coil group includes hairpin coils with three spans, and the three spans are Z / (2p)-1, Z / (2p) and Z / (2p)+1 respectively. In the m-phase winding of the stator winding, each phase winding includes two parallel branches, and the incoming end of each parallel branch of each phase winding can be led out from the flat wire conductor of the same layer, and the number of spaced stator slots can be less than or equal to 2. At the same time, the emerging end of each parallel branch of each phase winding can also be led out from the flat wire conductor of the same layer, and the number of spaced stator slots can be less than or equal to 2. As a result, the incoming and outgoing ends of each parallel branch are all drawn out from the same layer, and when the busbar is used for connection, the introduction of special-shaped connecting wires for cross-connection can be avoided. At the same time, in the axial direction of the stator core, the various connecting parts of the busbar can be arranged on the same layer, avoiding the situation where the various connecting parts of the busbar are stacked. The motor stator of the present application can make full use of the radial space of the stator winding, which is beneficial to reducing the height of the entire motor stator. In addition, since the structure of the busbar is simpler, the injection molding parts can be saved, which is beneficial to reducing the material cost and manufacturing cost of the entire motor stator. In addition, in the stator winding of the present application, the card-issuing coils are independent of each other, and there is no need to use cross-layer card-issuing coils. Fully automatic wire insertion can be achieved through independent wire cups, which simplifies the manufacturing process and facilitates large-scale quantitative production.

[0007] In one possible implementation, the stator winding has three slots per pole and per phase, and the spans of the flat wire conductors of any parallel branch within any coil group are a combination of 8, 9, 9, 9, 9, and 10. In this connection method, the flat wire conductors of each parallel branch are evenly distributed at different layers within the stator slots of each pole and phase. The back EMF and current of each parallel branch are identical, eliminating additional copper loss in the stator winding caused by uneven parallel branches. This ensures temperature uniformity in the stator winding and thus improves motor life.

[0008] In a possible implementation, among the N / 2 coil groups, a flat wire conductor in the 2kth layer of any coil group is connected to a flat wire conductor in the 2k+1th layer of another adjacent coil group, thereby achieving connection between different coil groups.

[0009] In one possible implementation, the incoming wire ends of each of the parallel branches of each phase winding are drawn out from the flat wire conductor of the same layer, and the number of stator slots spaced apart is less than or equal to 2; the outgoing wire ends of each of the parallel branches of each phase winding are drawn out from the flat wire conductor of the same layer, and the number of stator slots spaced apart is less than or equal to 2. In one possible implementation, the incoming wire ends and outgoing wire ends of each parallel branch are drawn out from the flat wire conductor of the slot bottom layer of the stator slot. The flat wire conductor of the slot bottom layer of the stator slot is the flat wire conductor in the stator slot away from the axis of the stator core. The incoming wire ends and outgoing wire ends of each parallel branch are drawn out from the flat wire conductor of the slot bottom layer, which can further simplify the connection structure of the busbar and avoid the connection part of the busbar crossing the flat wire conductor. At the same time, drawing out from the flat wire conductor of the slot bottom layer can reduce the electrical stress of the flat wire conductor of the slot mouth layer, thereby reducing the insulation risk of the stator winding.

[0010] In one possible implementation, the incoming wire ends of each parallel branch of each phase winding are separated by two stator slots, and the outgoing wire ends of each parallel branch of each phase winding are separated by one stator slot. In another possible implementation, the incoming wire ends of each parallel branch of each phase winding are separated by one stator slot, and the outgoing wire ends of each parallel branch of each phase winding are separated by two stator slots. This allows the incoming wire ends of each parallel branch to be closely spaced, and the outgoing wire ends of each parallel branch to be closely spaced. When connecting the incoming and outgoing wire ends to the busbar, the busbar structure can be simplified, making it easier to connect the parallel branches.

[0011] In one possible implementation, the incoming terminals of the corresponding parallel branches of each phase winding are spaced apart by 4q stator slots, thereby avoiding interference between the incoming terminals and outgoing terminals of windings of different phases.

[0012] In one possible implementation, the stator winding has 3N / 2 types of hairpin coils, and any coil group has 3 types of hairpin coils. The hairpin coils have a small number of wire types, making them easier to manufacture and facilitate automated wire insertion.

[0013] In one possible implementation, in any coil group, each phase winding includes 2pq hairpin coils, where the number of hairpin coils with a span of Z / (2p)-1 is 2, the number of hairpin coils with a span of Z / (2p) is 2pq-4, and the number of hairpin coils with a span of Z / (2p)+1 is 2. In one possible implementation, in any coil group, each parallel branch of each phase winding includes one hairpin coil with a span of Z / (2p)-1, the number of hairpin coils with a span of Z / (2p) is pq-2, and the number of hairpin coils with a span of Z / (2p)+1 is 1.

[0014] In one possible implementation, each phase winding has two jumper wires at the welding end. In another possible implementation, the jumper wires include enameled wires or copper busbars. This effectively reduces the number of jumper wires at the welding end, simplifies the structure of the welding end, and further simplifies the stator winding structure.

[0015] In a possible implementation, the lead wires of each winding are connected in a Y-type or a △-type manner.

[0016] In a second aspect, the present application provides a flat wire motor, which includes a rotor and a stator. The rotor is disposed in a space enclosed by an inner wall of a stator core.

[0017] The flat wire motors of this application include, but are not limited to, permanent magnet synchronous motors, electrically excited synchronous motors, and asynchronous motors. The rotor of a flat wire motor can have any rotor topology, such as surface mount, internal "single" type, internal V-type, internal double V-type, internal U-type, or internal UV-type. The flat wire motors of this application can be used in electric vehicles, traction motors for high-speed trains, aerospace electric propulsion motors, and marine electric propulsion motors.

[0018] In a third aspect, the present application provides a power assembly, which includes a reducer and the flat wire motor of the second aspect, wherein the flat wire motor is transmission-connected to the reducer.

[0019] In a fourth aspect, the present application provides a power device, which includes the power assembly of the third aspect of the present application.

[0020] The power device of the present application includes but is not limited to electric vehicles, power trains, aviation devices, aerospace devices or ships.

[0021] The technical effects that can be achieved in the second to fourth aspects mentioned above can be described with reference to the corresponding effects in the first aspect mentioned above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1This is a structural diagram of a welding end of an existing motor stator;

[0023] Figure 2 This is a schematic diagram of the front view structure of a conventional motor stator;

[0024] Figure 3 This is a schematic structural diagram of the crown end of the motor electronics according to one embodiment of the present application;

[0025] Figure 4 This is a schematic structural diagram of the welding end of the motor electronics according to one embodiment of the present application;

[0026] Figure 5 This is a schematic structural diagram of a stator core according to an embodiment of the present application;

[0027] Figure 6 This is a structural diagram of a card issuing coil according to an embodiment of the present application;

[0028] Figure 7 This is a schematic diagram of the distribution structure of flat wire conductors in stator slots according to an embodiment of the present application;

[0029] Figure 8 This is a schematic diagram of a Y-type connection structure of different phase windings in one embodiment of the present application;

[0030] Figure 9 This is a schematic diagram of a Δ-shaped connection structure of different phase windings in one embodiment of the present application;

[0031] Figure 10 Schematic diagram of the connection of the first parallel branch of the U-phase winding in this embodiment;

[0032] Figure 11 This is a connection diagram of the second parallel branch of the U-phase winding in one embodiment of the present application;

[0033] Figure 12 This is a schematic diagram of the connection structure of two parallel branches of the U phase according to an embodiment of the present application;

[0034] Figure 13 This is a schematic diagram of the connection structure of two parallel branches of the U phase in another embodiment of the present application;

[0035] Figure 14 This is a schematic diagram of the connection structure of two parallel branches of the U phase in another embodiment of the present application.

[0036] Reference numerals:

[0037] 10-fixed on the iron core; 10a-insertion end; 10b-extending end; 11-stator slot; 20-stator winding; 20a-crown end; 20b-welding end; 21-flat wire conductor; 22-hairpin coil; 221-first plug-in part; 222-second plug-in part; 223-connecting part; 224-first bending part; 225-second bending part; 23-busbar; 231-neutral conductor. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of this application clearer, this application will be further described in detail below with reference to the accompanying drawings.

[0039] The terms used in the following embodiments are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification and appended claims of this application, the singular expressions "a", "an", "said", "above", "the", and "this" are intended to also include expressions such as "one or more", unless the context clearly indicates otherwise.

[0040] References to "one embodiment" or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in yet other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0041] For easier understanding, the following explains the relevant terms.

[0042] Stator: refers to the stationary part of the motor, whose function is to generate a rotating magnetic field.

[0043] Rotor: refers to the rotating part in the motor, which is used to realize the conversion of electrical energy into mechanical energy.

[0044] Number of poles: the number of magnetic poles of the motor. The magnetic poles are divided into N poles and S poles. Generally, one N pole and one S pole are called a pair of magnetic poles, that is, the number of pole pairs is 1. Therefore, if the number of pole pairs of the motor is 1, 2, 3, or 4, the number of poles of the motor is 2, 4, 6, or 8.

[0045] Number of slots per pole per phase q: The number of slots occupied by each phase winding under each magnetic pole is called the number of slots per pole per phase.

[0046] Flat wire motors are widely used in electric vehicles due to their high power and torque density. However, existing flat wire motors, due to structural limitations of their stator windings, have a complex busbar connection structure at the weld end, making it difficult to reduce the motor's size.

[0047] Figure 1 The figure is a structural diagram of the welding end of an existing motor stator. Figure 2 This is a schematic diagram of the front view of an existing motor stator. Figure 1 and Figure 2 As shown, in the existing motor stator, the incoming wire ends between different parallel branches of each phase winding are led out from different layers of flat wire conductors 21, and the outgoing wire ends between different parallel branches of each phase winding are also led out from different layers of flat wire conductors 21, and the number of stator slots between the incoming wire ends of each parallel branch is relatively large, and the number of stator slots between the outgoing wire ends of each parallel branch is also relatively large.

[0048] by Figure 1 Taking the structure shown as an example, the two parallel branch lead wires of each phase winding are located in the outermost and innermost layers respectively, and the space spans 9 slots. At the welding end, the three-phase lead copper bar of the busbar is longer, and the number of slots spanned by the center copper bar is 22 slots. The axial space requires two layers of copper bars, and the busbar height is relatively high. Figure 1 In the stator structure shown, electrical connections between the different parallel branches of each phase winding require numerous cross-layer and cross-slot connecting wires atop the flat conductor 21. A neutral copper busbar with welded ends also needs to be placed atop the flat conductor. Consequently, this existing connection method results in a complex stator winding busbar connection structure. Furthermore, the busbar is too tall in the axial direction of the stator winding, making it difficult to further reduce the busbar's size, hindering motor size reduction.

[0049] In order to solve the above technical problems, an embodiment of the present application provides a motor stator. Figure 3 This is a schematic diagram of the three-dimensional structure of one side of the welding end of the stator of a flat wire motor according to an embodiment of the present application. Figure 4 This is a structural diagram of the crown end side of the stator of a flat wire motor according to an embodiment of the present application. Figure 3 and Figure 4 As shown, the stator includes a stator core 10 and a stator winding 20 .

[0050] The following is combined first Figures 3 to 5 The structure of the stator core 10 of the present application is explained.

[0051] Figure 5 FIG. 1 is a schematic structural diagram of a stator core according to an embodiment of the present invention. Figures 3 to 5As shown, the inner wall of the stator core 10 is provided with a plurality of stator slots 11, and the number of stator slots 11 can be represented by Z. Z can be a natural number that is a multiple of 3, and specifically 54, 72, etc. can be selected. The specific value of Z can be selected according to the design of the motor. Figure 4 and Figure 5 , Z stator slots 11 are provided on the inner wall of the stator core 10 and are evenly arranged along the circumferential direction of the inner wall of the stator core 10. Any stator slot 11 extends along the axial direction of the stator core 10 and passes through the inner wall of the stator core 10 along the axial direction of the stator core 10. The axial direction of the stator core 10, such as Figure 3 The stator core 10 is divided into an insertion end 10a and an extension end 10b along its axial direction, and any stator slot 11 can extend from the insertion end 10a to the extension end 10b.

[0052] The following will be combined Figures 3 to 7 The arrangement of the stator winding of the present application is described in detail.

[0053] Reference Figure 3 and Figure 4 The stator winding 20 can be formed by winding a plurality of hairpin coils 22. When the stator winding 20 is formed by winding the hairpin coils 22, each hairpin coil 22 can be inserted into the stator slot 11 from the insertion end 10a of the stator core 10 and extend from the extension end 10b. The hairpin coils 22 that make up the stator winding can be connected to form an m-phase winding. Each phase winding includes two parallel branches. In the embodiment of the present application, the number of slots Z of the stator slots 11 of the stator core 10 is 2mpq. P is the number of magnetic poles of the stator winding, and q is the number of slots per pole per phase of the stator winding. MPq is the product of m, p, and q. M, p, and q are all integers. For example, if the stator winding is a three-phase winding, that is, m is 3, the number of magnetic poles 2p is 6 poles, and the number of slots per pole per phase q is 3, then the number of stator slots Z on the stator core 10 is 54 slots. Exemplarily, when m is 3, the stator winding can be divided into a U-phase winding, a V-phase winding, and a W-phase winding.

[0054] After the stator windings are connected, the incoming wire ends of each parallel branch of each phase winding are separated by two stator slots, and the outgoing wire ends of each parallel branch of each phase winding are separated by one stator slot. Alternatively, the incoming wire ends of each parallel branch of each phase winding are separated by one stator slot, and the outgoing wire ends of each parallel branch of each phase winding are separated by two stator slots. The number of stator slots spaced between the incoming wire ends of the first parallel branches of each phase winding can be 4q stator slots, and the incoming wire ends of the second parallel branches of each phase winding are separated by 4q stator slots in turn. For example, taking q as 3 as an example. The number of stator slots spaced between the incoming wire ends of the first parallel branches of each phase winding can be 12, and the number of stator slots spaced between the incoming wire ends of the second parallel branches of each phase winding is also 12. For example, there are 12 stator slots between the incoming end of the first parallel branch of the U phase and the incoming end of the first parallel branch of the W phase, and there are 12 stator slots between the incoming end of the first parallel branch of the W phase and the first parallel branch of the V phase.

[0055] Continue to refer to Figure 3 and Figure 4 All the hairpin coils 22 forming the stator winding 20 can be divided into N / 2 coil groups, which can be recorded as the first coil group, the second coil group, ..., the N / 2 coil group, and each coil group includes multiple hairpin coils. Figure 6 This is a structural diagram of a hairpin coil according to an embodiment of the present application. Figure 6 As shown, each hairpin coil 22 includes a first connecting portion 221 and a second connecting portion 222 that are interconnected. In each of the N / 2 coil groups, the first connecting portion 221 and the second connecting portion 222 of each hairpin coil 22 are inserted into different stator slots 11 to form the flat wire conductor 21. The first connecting portion 221 and the second connecting portion 222 of each hairpin coil 22 in the kth coil group are inserted into the 2k-1th and 2kth layers of flat wire conductors, respectively, forming adjacent pole phases, where k ranges from 1 to N / 2.

[0056] Taking N as 6 as an example, the stator winding 20 can be divided into three coil groups. The first and second plug-in portions 221, 222 of each hairpin coil 22 in the first coil group are inserted into the stator slots 11, respectively, to form the first and second layers of flat wire conductors 21. The first and second plug-in portions 221, 222 of each hairpin coil 22 in the second coil group are inserted into the stator slots 11, respectively, to form the third and fourth layers of flat wire conductors 21. The first and second plug-in portions 221, 222 of each hairpin coil 22 in the third coil group are inserted into the stator slots 11, respectively, to form the fifth and sixth layers of flat wire conductors 21. Taking N as 10 as an example, the stator winding 20 can be divided into five coil groups. The first plug-in portion 221 and the second plug-in portion 222 of each hairpin coil 22 of the first coil group are inserted into the stator slots 11, respectively, to form the first and second layers of flat wire conductors 21. The first plug-in portion 221 and the second plug-in portion 222 of each hairpin coil 22 of the second coil group are inserted into the stator slots 11, respectively, to form the third and fourth layers of flat wire conductors 21. The first plug-in portion 221 and the second plug-in portion 222 of each hairpin coil 22 of the third coil group are inserted into the stator slots 11, respectively, to form the fifth and sixth layers of flat wire conductors 21. The first plug-in portion 221 and the second plug-in portion 222 of each hairpin coil 22 of the fourth coil group are inserted into the stator slots 11, respectively, to form the seventh and eighth layers of flat wire conductors 21. The first plug-in portion 221 and the second plug-in portion 222 of each hairpin coil 22 of the fifth coil group are respectively inserted into the stator slots 11 to form the ninth and tenth layers of flat wire conductors 21. The first plug-in portion 221 and the second plug-in portion 222 of each hairpin coil 22 are respectively inserted into the stator slots 11 of adjacent pole phases.

[0057] Each of the first, second, ..., and N / 2 coil groups includes three types of hairpin coils, each with a span of Z / (2p)-1, Z / (2p), and Z / (2p)+1. The hairpin coil with a span of Z / (2p)-1 and the hairpin coil with a span of Z / (2p)+1 are located in the same pole-phase group. With this configuration, the total number of hairpin coil types in the stator winding of the present application is 3N / 2, effectively reducing the number of hairpin coil types.

[0058] In any coil group, each phase winding includes 2pq hairpin coils. Among them, the number of hairpin coils with a span of Z / (2p)-1 is 2, the number of hairpin coils with a span of Z / (2p) is 2pq-4, and the number of hairpin coils with a span of Z / (2p)+1 is 2. In any coil group, the hairpin coils are evenly distributed in each parallel branch of each phase winding. Moreover, in any coil group, each parallel branch of each phase winding includes 1 hairpin coil with a span of Z / (2p)-1, the number of hairpin coils with a span of Z / (2p) is pq-2, and the number of hairpin coils with a span of Z / (2p)+1 is 1. In an optional embodiment, the number of slots per pole and per phase of the stator winding is 3, and the spans of the hairpin coils in any parallel branch in any coil group are a combination of 8, 9, 9, 9, 9, and 10.

[0059] Continue to refer to Figure 6 As an example, the hairpin coil 22 includes a first plug-in portion 221, a second plug-in portion 222, a connecting portion 223, a first bending portion 224, and a second bending portion 225. The first bending portion 224, the first plug-in portion 221, the connecting portion 223, the second plug-in portion 222, and the second bending portion 225 are sequentially connected to form a U-shaped coil or a V-shaped coil. Figures 3 to 6 After the hairpin coil 22 is inserted into the stator slot 11 of the stator core 10 to form the stator winding 20, the connecting portion 223 of the hairpin coil 22 is located on the side of the insertion end 10a of the stator core 10 to form the crown end 20a of the stator winding 20, and the first bent portion 224 and the second bent portion 225 are located on the side of the extension end 10b of the stator core 10 to form the welding end 20b of the stator winding 20. After the hairpin coil 22 is inserted into the stator slot 11, the portions of the first plug-in portion 221 and the second plug-in portion 222 extending from the stator core 10 are bent to form the first bent portion 224 and the second bent portion 225. After the insertion is completed, the first plug-in portion 221 and the second plug-in portion 222 form the flat wire conductor 21, and the cross-section of the flat wire conductor 21 can be rectangular.

[0060] Figure 7 FIG. 1 is a top view of a flat wire conductor 21 inserted into a stator slot 11 according to an embodiment of the present application. Figure 7 As shown, in one embodiment of the present application, N layers of flat wire conductors 21 can be set in any stator slot 11. N is a multiple of 2. For example, N can be 4, 6, 8, 10, 12, 14 or an even number greater than 14. Figure 7 As shown, when N is 6, each stator slot 11 is provided with 6 layers of flat wire conductors 21. It is understandable that Figure 7The number of layers of the flat wire conductors 21 shown is for illustrative purposes only. In addition to six layers of flat wire conductors 21 , other even-numbered layers of flat wire conductors 21 may also be provided. The number of layers of the flat wire conductors 21 in each stator slot 11 is not specifically limited herein.

[0061] like Figure 7 As shown, each stator slot 11 is provided with N layers of flat wire conductors 21. From the bottom of each stator slot 11 to the slot opening, the N layers of flat wire conductors 21 are denoted as L1 layer, L2 layer, ..., L N-1 Layer and L N Layer, wherein, in the radial direction of the stator core 10 , the slot opening of the stator slot 11 is arranged close to the axis of the stator core 10 , and the slot bottom of the stator slot 11 is arranged away from the axis of the stator core 10 .

[0062] It will be appreciated that as the number of stator slots 11 in the stator core 10 increases and the number of layers of flat wire conductors 21 within each stator slot 11 increases, the number of hairpin coils 22 required also increases. The number of hairpin coils 22 can be determined by the number Z of stator slots 11 and the number N of layers of flat wire conductors 21 within each stator slot 11. Among the N / 2 coil groups, a flat wire conductor in the 2kth layer of any coil group is connected to a flat wire conductor in the 2k+1th layer of the adjacent coil group. Each phase winding can have two jumper wires at the welding end, and these jumper wires can be enameled wire or copper busbars.

[0063] In the stator winding of the present application, the incoming wire ends of each parallel branch of each phase winding are all led out from the flat wire conductor of the same layer, and the number of stator slots between them is less than or equal to 2. The outgoing wire ends of each parallel branch of each phase winding are all led out from the flat wire conductor of the same layer, and the number of stator slots between them is less than or equal to 2. Figure 3 As shown, in an optional embodiment, the inlet and outlet of each parallel branch are both led out from the flat wire conductor 21 at the bottom of the stator slot 11. For example, the inlet of each parallel main circuit is led out from L N The flat conductor 21 is led out, and the outgoing terminals of each parallel main circuit are also connected from L N The flat conductor 21 is led out of the layer. Thus, when installing the busbar 23, the radial space of the stator can be fully utilized. The busbar 23 is positioned at the weld end 20b of the stator winding 20 and on the outer periphery of the stator winding 20, that is, on the side away from the axis of the stator core 10. This arrangement avoids having the busbar 23 connection portion located at the top of the stator winding 20, that is, on top of the first and second plug-in portions 221, 222 of the hairpin coil 22. Furthermore, the neutral conductor 231 between each parallel branch can also be positioned on the outer periphery of the stator winding 20, thereby significantly reducing the size of the busbar 23 in the axial direction of the stator winding 20.

[0064] Figure 8and Figure 9 The end connection methods of each phase winding are shown, which can be Y-type connection and Δ-type connection.

[0065] Based on the same technical concept, an embodiment of the present application further provides a flat wire motor, which includes a rotor and a stator according to an embodiment of the present application. The rotor is disposed in a space enclosed by an inner wall of a stator core.

[0066] Based on the same technical concept, embodiments of the present application also provide a powertrain comprising a reducer and the aforementioned flat wire motor. The flat wire motor and reducer are in transmission connection. Specifically, the flat wire motor's drive shaft and the reducer's input shaft can be connected via a transmission member such as a coupling, thereby outputting driving force from the flat wire motor to the reducer.

[0067] Based on the same technical concept, the power device provided in the embodiment of the present application may include the above-mentioned power assembly. The above-mentioned power assembly is arranged in the power device and provides operating power for the power device. Specifically, the power device may be a device that needs to be powered, such as a vehicle, an aerospace device, a power train, a ship, etc. The vehicle may specifically be a new energy vehicle driven by electric energy. Among them, the new energy vehicle may specifically be a hybrid electric vehicle, a pure electric vehicle or a fuel cell electric vehicle, etc., or it may be a vehicle that uses a high-efficiency energy storage device such as a supercapacitor, a flywheel battery or a flywheel energy storage device as a source of electric energy.

[0068] The following will describe in detail the connection method of the specific parallel branches in the embodiment of the present application in combination with specific embodiments.

[0069] Example 1

[0070] This embodiment is a stator of a flat wire motor. Figure 3 、 Figure 10 and Figure 11 The stator core 10 has 54 stator slots 11. The number of conductor layers in the stator slots 11 is 6. The number of stator poles is 6. The stator winding 20 is divided into U phase, V phase and W phase, and the number of slots per pole and per phase is 3. The number of parallel branches set for each phase winding is 2. The hairpin coils of the stator winding 20 are divided into 3 coil groups. Among them, the hairpin coils inserted to form the first and second layers constitute the first coil group. The hairpin coils inserted to form the third and fourth layers constitute the second coil group. The hairpin coils inserted to form the fifth and sixth layers constitute the third coil group.

[0071] Taking the U-phase winding as an example, the phase band distribution diagram of the two parallel branches of the U-phase winding in this embodiment can be referred to Figure 10 and Figure 11 . Figure 10 Schematic diagram of the connection of the first parallel branch of the U-phase winding in this embodiment. Figure 11 FIG. 1 is a connection diagram of the second parallel branch of the U-phase winding in this embodiment. Figure 10 and Figure 11 As shown, each stator slot 11 contains six layers of flat wire conductors 21, with the first layer being designated L1, the second layer being designated L2, the third layer being designated L3, the fourth layer being designated L4, the fifth layer being designated L5, and the sixth layer being designated L6. The first layer is the bottom layer of the stator slot 11, and the sixth layer is the slot opening layer. In the phase band diagram, "+" represents current flowing into the flat wire conductor 21, and "-" represents current flowing out of the flat wire conductor 21. It should be noted that Figure 11 The phase band distribution in the figure is only for illustration purposes. Figure 11 The "+" and "-" symbols in Figure 11 "U + ” to “U - ”, and “U - ” to “U + ", V phase and W phase are also modified accordingly and are within the protection scope of this application.

[0072] Refer to Figure 3 、 Figure 10 and Figure 11 , the solid connecting line represents the connection mode of the stator winding 20 at the crown end 20a, and the dotted connecting line represents the connection mode of the stator winding 20 at the welding end 20b.

[0073] The following combination Figure 3 and Figure 10 , the wiring method of the first parallel branch of the U phase in this embodiment is described in detail. Figure 10 The dotted line connection method in the figure illustrates the connection method of the stator winding 20 at the welding end 20b. The connection method of the stator winding 20 at the crown end 20a can be directly connected by the connecting portion 223 of the hairpin coil 22. Figure 10 The connection method of the solid lines in .

[0074] Reference Figure 10The first parallel branch of the U phase begins with the L1-layer flat wire conductor in slot 10 and is connected in a counterclockwise direction. The L1-layer flat wire conductor in slot 10 serves as the inlet terminal U1in for the first parallel branch. Within the first coil group, it passes through a short-span hairpin coil with a span of 8, four full-span hairpin coils with a span of 9, and one long-span hairpin coil with a span of 10, before returning to the L2-layer flat wire conductor in slot 19. At the welding end, it is directly welded to the L3-layer flat wire conductor in slot 10, thereby switching from the first coil group to the second coil group without the need for additional cross-layer wires. Similarly, the arrangement of the first parallel branch of the U phase in the second and third coil groups is the same as that in the first coil group. The L4-layer flat wire conductor in slot 19 is directly welded to the L5-layer flat wire conductor in slot 10 at the welding end to switch from the second coil group to the third coil group. The first parallel branch, within the third coil group, passes through one short-span hairpin coil with a span of 8, four full-span hairpin coils with a span of 9, and one long-span hairpin coil with a span of 10. A return line connects the flat wire conductor on the L6 layer in slot 19 and the flat wire conductor on the L6 layer in slot 12, achieving north-south pole switching. The return line can be directly welded using enameled wire or copper busbar.

[0075] Continue to refer to Figure 10 After connecting the flat wire conductors on the L6 layer in slot 19 and the flat wire conductors on the L6 layer in slot 12 with a return line, the conductors travel clockwise through three hairpin coils with a span of 9, returning to the flat wire conductors on the L5 layer in slot 3. The welding end is directly welded to the flat wire conductors on the L4 layer in slot 12, switching from the third coil group to the second coil group. Within the second coil group, the conductors are connected in the same manner as the third coil group, returning to the flat wire conductors on the L3 layer in slot 3, and directly welded to the flat wire conductors on the L2 layer in slot 12, switching from the second coil group to the first coil group. Within the first coil group, the conductors are connected in the same manner as the second coil group, returning to the flat wire conductors on the L1 layer in slot 3. The output terminal U1out of the first parallel branch of the U phase is drawn out from the flat wire conductors on the L1 layer in slot 3.

[0076] The following combination Figure 3 and Figure 11 , the connection mode of the second parallel branch of the U phase in this embodiment is described in detail. Figure 12 The dotted line connection method in the figure illustrates the connection method of the stator winding 20 at the welding end 20b. The connection method of the stator winding 20 at the crown end 20a can be directly connected by the connecting portion 223 of the hairpin coil 22. Figure 11 The connection method of the solid lines in .

[0077] Reference Figure 11The second parallel branch of the U phase starts from the L1-layer flat wire conductor in slot 12 and is connected in a counterclockwise direction. The L1-layer flat wire conductor in slot 12 is the inlet terminal U2in of the second parallel branch. In the first coil group, it passes through a short-span hairpin coil with a span of 8, four full-span hairpin coils with a span of 9, and one long-span hairpin coil with a span of 10, and returns to the L2-layer flat wire conductor in slot 21. It is directly welded to the L3-layer flat wire conductor in slot 12 at the welding end, thereby achieving the switch from the first coil group to the second coil group without the use of additional cross-layer wires. Similarly, the arrangement of the second parallel branch of the U phase in the second coil group and the third coil group is the same as that in the first coil group. The L4-layer flat wire conductor in slot 21 is directly welded to the L5-layer flat wire conductor in slot 12 at the welding end to achieve the switch from the second coil group to the third coil group. The second parallel branch, within the third coil group, passes through one short-span hairpin coil with a span of 8, four full-span hairpin coils with a span of 9, and one long-span hairpin coil with a span of 10. A return line connects the flat wire conductor on the L6 layer of slot 21 and the flat wire conductor on the L6 layer of slot 11, achieving north-south pole switching. The return line can be directly welded using enameled wire or copper busbar.

[0078] Continue to refer to Figure 11 After connecting the flat wire conductors on the L6 layer in slot 21 and the flat wire conductors on the L6 layer in slot 11 with a return line, the conductors travel clockwise through three hairpin coils with a span of 9, returning to the flat wire conductors on the L5 layer in slot 2. The soldering end is directly welded to the flat wire conductors on the L4 layer in slot 11, switching from the third coil group to the second coil group. Within the second coil group, the conductors are connected in the same manner as the third coil group, returning to the flat wire conductors on the L3 layer in slot 2, and directly soldered to the flat wire conductors on the L2 layer in slot 11, switching from the second coil group to the first coil group. Within the first coil group, the conductors are connected in the same manner as the second coil group, returning to the flat wire conductors on the L1 layer in slot 2. The output terminal U2out of the second parallel branch of the U phase is led out from the flat wire conductors on the L1 layer in slot 2.

[0079] according to Figure 10 and Figure 11The connection structure shown here translates the phase band of the U-phase winding to create the parallel branches of the W-phase and V-phase windings. The inlet terminal W1in of the first parallel branch of the W-phase winding is a flat wire conductor with an L1 layer in slot 22. The inlet terminal W2in of the second parallel branch of the W-phase winding is a flat wire conductor with an L1 layer in slot 24. The outlet terminal W1out of the first parallel branch of the W-phase winding is a flat wire conductor with an L1 layer in slot 15. The inlet terminal W2out of the second parallel branch of the W-phase winding is a flat wire conductor with an L1 layer in slot 14. The inlet terminal V1in of the first parallel branch of the V-phase winding is a flat wire conductor with an L1 layer in slot 34. The inlet terminal V2in of the second parallel branch of the V-phase winding is a flat wire conductor with an L1 layer in slot 36. The outlet terminal V1out of the first parallel branch of the V-phase winding is a flat wire conductor with an L1 layer in slot 27. The line-in terminal V2out of the second parallel branch of the V-phase winding is the L1 layer flat wire conductor in slot 28.

[0080] Refer to Figure 10 and Figure 11 Each coil group includes three types of hairpin coils with spans of 8, 9, and 10 at the crown end. Among them, there is one hairpin coil with a span of 8 and one hairpin coil with a span of 10 in each coil group, and the rest are hairpin coils with a span of 9. The hairpin coils with a span of 8 and a span of 10 are all located in the same pole phase group. The total number of hairpin coil line types in each coil group is 9. Figure 11 and Figure 12 As shown by the solid connecting line in the middle, there are no cross-layer card-pinning coils between the 2nd and 3rd layers, and no cross-layer card-pinning coils between the 4th and 5th layers in the entire stator winding. Therefore, each card-pinning coil of the present application can use an independent wire cup to achieve fully automatic wire insertion, and the wire insertion process is simple.

[0081] Figure 12 FIG. 1 is a schematic diagram of a U-phase connection structure of an embodiment. Figure 12 As shown, the incoming terminals of the first and second parallel branches of the U-phase winding are separated by two stator slots, and the outgoing terminals of the first and second parallel branches of the U-phase winding are separated by one stator slot. Similarly, the incoming terminals of the first and second parallel branches of the W-phase winding are separated by two stator slots, and the outgoing terminals of the first and second parallel branches of the V-phase winding are separated by one stator slot. This connection method significantly simplifies the busbar connection structure, allowing the busbar to connect the parallel paths of different windings in the direction of stator winding, which helps reduce the busbar connection height.

[0082] Continue to refer to Figure 12 ,exist Figure 12, the inlet terminal W1in of the first parallel branch of the W-phase winding and the inlet terminal W2in of the second parallel branch are shown, and the inlet terminal V1in of the first parallel branch of the V-phase winding and the inlet terminal V2in of the second parallel branch are shown. Figure 12 As shown, the incoming wire ends of the first parallel branches of each phase winding are spaced 12 stator slots apart, and the incoming wire ends of the second parallel branches of each phase winding are spaced 12 stator slots apart, thereby avoiding mutual interference between the return lines of the parallel branches at the welding ends.

[0083] The structure of the stator formed by the connection method of the embodiment of the present application is such that the lead-out wires of each phase are at the welding end of the stator winding, and the flat wire conductors corresponding to the incoming and outgoing wire ends of the parallel branches of each phase winding are located at the same layer at the bottom of the slot. The flat wire conductors corresponding to the incoming wire ends of the two parallel branches of each phase winding are separated by two stator slots, and the flat wire conductors corresponding to the outgoing wire ends of the two parallel branches of each phase winding are separated by one stator slot. Under this lead-out method, the conductor lead-out method in the slot can be directly used for connection, or enameled wire can be used as the neutral wire and lead-out wire. In this way, the radial space of the stator can be fully utilized, saving axial space. Figure 1 and Figure 2 Compared to the connection shown above, the busbar in this embodiment occupies only one conductor layer in the axial space, while the existing solution, due to its injection-molded structure, has two conductor layers, two electrical distances, and two injection-molded layer thicknesses. Therefore, this connection method can shorten the stator weld end in the axial direction, reducing the end height by approximately 8-9 mm.

[0084] Example 2

[0085] This embodiment is a stator of a flat wire motor. In the stator, refer to Figure 3 and Figure 13 The stator core 10 has 54 stator slots 11. The number of conductor layers in the stator slots 11 is 8. The number of stator poles is 6. The stator winding 20 is divided into U phase, V phase and W phase. The number of slots per pole and per phase is 3. The number of parallel branches set for each phase winding is 2. The hairpin coils of the stator winding 20 are divided into 4 coil groups. Among them, the hairpin coils inserted to form the 1st and 2nd layers of flat wire conductors 21 constitute the 1st coil group, the hairpin coils inserted to form the 3rd and 4th layers of flat wire conductors constitute the 2nd coil group, the hairpin coils inserted to form the 5th and 6th layers of flat wire conductors constitute the 3rd coil group, and the hairpin coils inserted to form the 7th and 8th layers of flat wire conductors constitute the 4th coil group.

[0086] Figure 13 This is a schematic diagram of the connection structure of two parallel branches of the U phase in another embodiment of the present application. Figure 13As shown, taking the U phase as an example, each stator slot 11 in this embodiment contains eight layers of flat wire conductors 21, with the first layer being L1, the second layer being L2, the third layer being L3, the fourth layer being L4, the fifth layer being L5, the sixth layer being L6, the seventh layer being L7, and the eighth layer being L8. The first layer is the bottom layer of the stator slot 11, and the eighth layer is the slot opening layer. Figure 13 In FIG. 1 , the solid connecting line represents the connection mode of the stator winding 20 at the crown end 20 a , and the dotted connecting line represents the connection mode of the stator winding 20 at the welding end 20 b .

[0087] Reference Figure 13 In the two parallel branches of the U-phase winding, U1in of the first parallel branch is led out from the flat wire conductor of the L1 layer in slot 10, and U2in of the second parallel branch is led out from the flat wire conductor of the L1 layer in slot 12. U1out of the first parallel branch is led out from the flat wire conductor of the L1 layer in slot 3, and U2out of the second parallel branch is led out from the flat wire conductor of the L1 layer in slot 2. Specifically, the connection structure of each parallel branch in this embodiment can refer to Example 1, and the connection of the fourth coil group is added on the basis of Example 1, and the connection rules are the same as those of other coil groups. Among them, the N and S poles of the first parallel branch are switched between the flat wire conductor of the L8 layer in slot 19 and the flat wire conductor of the L8 layer in slot 12. The N and S poles of the second parallel branch are switched between the flat wire conductor of the L8 layer in slot 21 and the flat wire conductor of the L8 layer in slot 10. It can be understood that the connection structure of the parallel branches of the W-phase winding and the V-phase winding can refer to the U-phase winding and can be obtained by translation based on the U-phase winding, and will not be repeated here.

[0088] Similarly, in the embodiment of the present application, the input ends of the two parallel branches of each phase winding are separated by two stator slots, and the flat wire conductors corresponding to the output ends of the two parallel branches of each phase winding are separated by one stator slot, which can achieve the same beneficial effects as in Example 1.

[0089] Example 3

[0090] This embodiment is a stator of a flat wire motor. Figure 14 This is a schematic diagram of the connection structure of the two parallel branches of the U phase of another embodiment of the present application. Figure 3 and Figure 14 The stator core 10 has 72 stator slots 11. The number of conductor layers in the stator slots 11 is 6. The number of stator poles is 8. The stator winding 20 is divided into U phase, V phase and W phase, and the number of slots per pole and per phase is 3. The number of parallel branches set in each phase winding is 2. The hairpin coils of the stator winding are divided into 3 coil groups, among which the hairpin coils inserted to form the 1st and 2nd layers of flat wire conductors constitute the 1st coil group, the hairpin coils inserted to form the 3rd and 4th layers of flat wire conductors constitute the 2nd coil group, and the hairpin coils inserted to form the 5th and 6th layers of flat wire conductors constitute the 3rd coil group.

[0091] Reference Figure 14 In the stator winding of the embodiment of the present application, the incoming wires of each parallel branch are led out from the flat wire conductor on the L1 layer, and the outgoing wires of each parallel branch are also led out from the flat wire conductor on the L1 layer. The incoming wires of the two parallel branches of each phase winding are separated by two stator slots, and the outgoing wires of the two parallel branches of each phase winding are separated by one stator slot. The north and south pole switching positions of each parallel branch are located on the flat wire conductor on the L6 layer. The connection structure of the embodiment of the present application can achieve the same beneficial effects as the first embodiment.

[0092] It should be noted that in Examples 1 through 3, the incoming and outgoing terminals of each parallel branch can be interchanged. For example, after the incoming and outgoing terminals of each parallel branch are interchanged in the contact of Example 1, the incoming terminals of the two parallel branches of each phase winding are separated by one stator slot, and the outgoing terminals of the two parallel branches of each phase winding are separated by two stator slots. Other connection structures are not affected. Each incoming and outgoing terminal is led out from the L1 layer flat wire conductor, and the effect of simplifying the busbar structure can still be achieved.

[0093] In summary, the motor stator according to the embodiment of the present application has the following advantages:

[0094] 1) The radial space of the stator can be fully utilized, the height of the entire end portion is reduced, and the injection molding process is omitted, thereby reducing the material cost and manufacturing cost of the entire stator assembly.

[0095] 2) As there are few types of hairpin coils and no special-shaped hairpin coils, fully automated wire insertion can be achieved through independent wire cups, which simplifies the manufacturing process and facilitates mass production.

[0096] 3) The back electromotive force and current of each parallel branch are exactly the same, which eliminates the additional copper loss of the winding circulation caused by each parallel branch, ensures the temperature uniformity of the stator winding, and thus improves the life of the motor.

[0097] 4) The electrical stress of the flat wire conductor in the notch layer is reduced, thereby reducing the insulation risk of the electronic winding.

[0098] 5) It is convenient to lead out the neutral line from the radial direction of the stator to achieve boost charging.

[0099] The above are only specific embodiments of the present application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A motor stator, characterized in that: It includes a stator core and a stator winding, wherein: The stator core includes Z stator slots, each of which is provided with N layers of flat wire conductors, where N is an even number ≥ 2; The stator winding includes m-phase windings, each phase winding includes two parallel branches, the number of magnetic poles of the stator winding is 2p, where p is an integer, and the m-phase winding includes N / 2 coil groups; Any coil group includes three types of hairpin coils with spans of [Z / (2p)]-1, Z / (2p) and [Z / (2p)]+1, and any of the hairpin coils includes a first plug-in portion and a second plug-in portion connected to each other. The first plug-in portion and the second plug-in portion of any of the hairpin coils are respectively inserted in different stator slots to form the flat wire conductor. The first plug-in portion and the second plug-in portion of each hairpin coil of the kth coil group are respectively inserted in the 2k-1 layer flat wire conductor and the 2k layer flat wire conductor of the adjacent pole phase, where k is an integer ranging from 1 to N / 2. The hairpin coil with a span of [Z / (2p)]-1 and the hairpin coil with a span of [Z / (2p)]+1 are located in the same pole phase group, and the hairpin coils in any of the coil groups are evenly distributed in the parallel branches of each phase winding.

2. The motor stator according to claim 1, characterized in that: The number of slots per pole and per phase of the stator winding is 3, and the span of the flat wire conductor of any parallel branch in any coil group is a combination of 8, 9, 9, 9, 9 and 10.

3. The motor stator according to claim 1, characterized in that: Among the N / 2 coil groups, one rectangular wire conductor of the 2kth layer of any coil group is connected to one rectangular wire conductor of the 2k+1th layer of another adjacent coil group.

4. The motor stator according to any one of claims 1 to 3, characterized in that: The incoming wire ends of each parallel branch of each phase winding are led out from the flat wire conductor of the same layer, and the number of spaced stator slots is less than or equal to 2; the outgoing wire ends of each parallel branch of each phase winding are led out from the flat wire conductor of the same layer, and the number of spaced stator slots is less than or equal to 2.

5. The motor stator according to claim 4, characterized in that: The inlet and outlet ends of each parallel branch are both led out from the flat wire conductor at the bottom layer of the stator slot.

6. The motor stator according to any one of claims 1 to 3, characterized in that: The incoming wire ends of the parallel branches of each phase winding are spaced apart by two stator slots, and the outgoing wire ends of the parallel branches of each phase winding are spaced apart by one stator slot.

7. The motor stator according to any one of claims 1 to 3, characterized in that: The incoming ends of the parallel branches of each phase winding are spaced apart by one stator slot, and the outgoing ends of the parallel branches of each phase winding are spaced apart by two stator slots.

8. The motor stator according to any one of claims 1 to 3, characterized in that: The incoming wire ends of the first parallel branches of each phase winding are spaced apart by 4q stator slots, and the incoming wire ends of the second parallel branches of each phase winding are spaced apart by 4q stator slots; wherein q is the number of slots per pole per phase.

9. The motor stator according to any one of claims 1 to 3, characterized in that: The number of types of the hairpin coils of the stator winding is 3N / 2, and the number of types of the hairpin coils of any coil group is 3.

10. The motor stator according to any one of claims 1 to 3, characterized in that: In any coil group, each phase winding includes 2pq hairpin coils, among which the number of hairpin coils with a span of [Z / (2p)]-1 is 2, the number of hairpin coils with a span of Z / (2p) is 2pq-4, and the number of hairpin coils with a span of [Z / (2p)]+1 is 2; wherein q is the number of slots per pole and per phase.

11. The motor stator according to any one of claims 1 to 3, characterized in that: In any coil group, each parallel branch of each phase winding includes 1 hairpin coil with a span of [Z / (2p)]-1, pq-2 hairpin coils with a span of Z / (2p), and 1 hairpin coil with a span of [Z / (2p)]+1; where q is the number of slots per pole and per phase.

12. The motor stator according to any one of claims 1 to 3, characterized in that: The number of jumper wires at the welding end of each phase winding is 2.

13. A flat wire motor, characterized in that: The invention comprises a rotor and a stator according to any one of claims 1 to 12, wherein the rotor is arranged in a space enclosed by an inner wall of the stator core.

14. A powertrain, characterized in that: The flat wire motor comprises a reducer and the flat wire motor as claimed in claim 13, wherein the flat wire motor is in driving connection with the reducer.

15. A power device, characterized in that: Comprising the powertrain as claimed in claim 14.

Images