Motor rotor cooling structure and motor

Abstract

The invention provides a motor rotor cooling structure, which comprises a rotor core provided with magnetic steel grooves; the magnetic steel is installed in the magnetic steel groove, a gap is reserved between the magnetic steel and the wall of the magnetic steel groove, the gap forms a cooling flow channel, and the cooling flow channel comprises a first cooling flow channel and a second cooling flow channel; the end face, facing the rotor core, of the first end plate is provided with a first oil guide groove which is communicated with the first cooling flow channel, the end face, facing the rotor core, of the second end plate is provided with a first oil outlet hole which is communicated with the first cooling flow channel, and the end face, facing the rotor core, of the second end plate is provided with a second oil guide groove which is communicated with the second oil outlet hole. The first end plate is provided with a first oil guide groove, the second oil guide groove is communicated with the second cooling flow channel, the first end plate is provided with a second oil outlet hole, the second oil outlet hole is communicated with the second cooling flow channel, and cooling oil can flow in opposite directions in the first cooling flow channel and the second cooling flow channel. The invention further relates to the hub motor.

Description

Motor rotor cooling structure and motor Technical Field

[0001] The present application relates to the technical field of motor cooling and heat dissipation, and in particular to a motor rotor cooling structure and a motor. Background Art

[0002] For motors (such as permanent magnet synchronous motors), the primary heat generation location is near the rotor core's magnetic steel. This heat not only affects motor performance but, in severe cases, can cause irreversible demagnetization of the magnetic steel. Therefore, the motor's rotor needs to be cooled, particularly near the rotor's magnetic steel.

[0003] In one possible solution, a through hole is provided on the rotor hub. Under the action of centrifugal force, the cooling oil in the rotor hub can pass through the through hole, so that the cooling oil flows through the end face of the rotor core, but the cooling oil cannot fully contact the magnetic steel, resulting in poor cooling effect.

[0004] In another possible solution, glue potting is used to fix the magnets in the magnet slots, and an axial channel is set in the rotor core for cooling oil to pass through, but the cooling oil cannot directly contact the magnets, resulting in poor cooling effect.

[0005] For example, CN115085432A discloses a new energy motor rotor oil cooling system, which uses glue to fix the magnets in the magnet slots. The cooling oil cannot directly contact the magnets, resulting in poor cooling effect.

[0006] Summary of the Invention

[0007] The purpose of the present application is to overcome or at least alleviate the deficiencies of the above-mentioned prior art and to provide a motor rotor cooling structure and a motor with better cooling effect.

[0008] An embodiment of the present application provides a motor rotor cooling structure, comprising:

[0009] a rotor core, wherein the rotor core is provided with magnetic steel slots;

[0010] a magnetic steel, the magnetic steel being mounted in the magnetic steel slot, with a gap being left between the magnetic steel and a wall of the magnetic steel slot, the gap forming a cooling channel, the cooling channel penetrating the rotor core along an axial direction of the rotor core, cooling oil passing through the cooling channel being able to directly contact the magnetic steel, the cooling channel comprising a first cooling channel and a second cooling channel, the first cooling channel being located radially outward of the second cooling channel;

[0011] a first end plate, the first end plate being disposed at one axial end of the rotor core, the first end plate being in contact with the rotor core, a first oil guide groove being disposed on an end surface of the first end plate facing the rotor core, the first oil guide groove being in communication with the first cooling channel, and

[0012] A second end plate is provided at the other axial end of the rotor core, the second end plate is in contact with the rotor core, and the second end plate is provided with a first oil outlet hole, the first oil outlet hole is in communication with the first cooling channel,

[0013] The end surface of the second end plate facing the rotor core is provided with a second oil guide groove, the second oil guide groove is connected to the second cooling flow channel, and the first end plate is provided with a second oil outlet hole, the second oil outlet hole is connected to the second cooling flow channel.

[0014] Cooling oil can flow in opposite directions in the first cooling flow channel and the second cooling flow channel.

[0015] In at least one possible embodiment, the motor rotor cooling structure further includes a rotor hub or a rotor shaft, and the rotor core, the first end plate, and the second end plate are sleeved on the rotor hub or the rotor shaft.

[0016] The rotor hub or the rotor shaft is provided with a first oil inlet hole and a second oil inlet hole, both of which penetrate the peripheral wall of the rotor hub or the rotor shaft, and the first oil inlet hole and the second oil inlet hole are spaced apart in the axial direction of the rotor hub or the rotor shaft.

[0017] The first oil inlet hole is communicated with the first oil guide groove, and the second oil inlet hole is communicated with the second oil guide groove.

[0018] In at least one possible embodiment, the magnetic steel slot is V-shaped, and two or two groups of the magnetic steels are installed in the V-shaped magnetic steel slot. The tip of the V-shape points to the radial inner side of the rotor core, and the forked end of the V-shape points to the radial outer side of the rotor core. The first cooling channel is located at the forked end of the V-shape, and the second cooling channel is located at the tip of the V-shape.

[0019] In at least one possible embodiment, the first oil guide groove includes a straight section and two forked sections, one end of the straight section extends to the inner periphery of the first end plate, the other end of the straight section is connected to the forked section, and the two forked sections are each connected to one of the first cooling channels.

[0020] In at least one possible implementation manner, the two bifurcated sections are respectively connected to two adjacent bifurcated ends of two adjacent V-shaped magnetic steel slots.

[0021] In at least one possible implementation manner, the first oil guiding groove is not connected to the second cooling channel, and the second oil guiding groove is not connected to the first cooling channel.

[0022] In at least one possible embodiment, a plurality of first oil guide grooves are provided, and the plurality of first oil guide grooves are independent of each other and not interconnected.

[0023] There are multiple second oil guiding grooves, and the multiple second oil guiding grooves are independent of each other and not connected to each other.

[0024] In at least one possible embodiment, the motor rotor cooling structure further includes an elastomer, which is disposed between the radial inner wall of the magnetic steel slot and the magnetic steel, so that a gap is formed between the magnetic steel and the radial inner wall of the magnetic steel slot. The elastomer is formed by bending and / or curling a sheet material, so that the gap can allow cooling oil to pass through.

[0025] In at least one possible embodiment, the magnetic steel slot is provided with a limiting protrusion, the limiting protrusion and the elastic body are located at both ends of the magnetic steel, the elastic body makes the magnetic steel abut against the limiting protrusion, and the limiting protrusion leaves a gap between the magnetic steel and the radial outer side wall of the magnetic steel slot.

[0026] An embodiment of the present application further provides a motor, comprising the motor rotor cooling structure described in any one of the above technical solutions.

[0027] By adopting the above technical solution, the cooling oil can pass through the magnetic steel slots, and the cooling oil directly contacts the magnetic steel to take away the heat of the magnetic steel and the rotor core, thereby achieving a better heat dissipation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG1 shows a schematic structural diagram of a rotor assembly of a motor according to one embodiment of the present application.

[0029] FIG2 shows another schematic structural diagram of a rotor assembly of a motor according to an embodiment of the present application.

[0030] FIG3 shows a schematic structural diagram of a rotor core and magnetic steel of a rotor assembly of a motor according to an embodiment of the present application.

[0031] 4 and 5 are cross-sectional views of a rotor assembly of a motor according to one embodiment of the present application.

[0032] FIG6 shows an exploded view of a rotor assembly of a motor according to one embodiment of the present application.

[0033] FIG7 shows a schematic structural diagram of a first end plate of a rotor assembly of a motor according to an embodiment of the present application.

[0034] FIG8 shows a schematic structural diagram of a second end plate of a rotor assembly of a motor according to an embodiment of the present application.

[0035] FIG9 shows a partially enlarged view of a magnetic steel mounting structure of a rotor assembly of a motor according to an embodiment of the present application. DETAILED DESCRIPTION

[0036] Exemplary embodiments of the present application are described below with reference to the accompanying drawings.

[0037] 1 to 9 , embodiments of the present application provide an electric motor, which can be used in a hybrid vehicle powertrain. The motor can be used in a P1 generator module or range extender module of the vehicle powertrain, or as an in-wheel motor. The motor includes a rotor assembly and a stator.

[0038] The rotor assembly includes a rotor hub 1, a rotor core 2, a magnetic steel 3, a first end plate 4, a second end plate 5 and an elastic body 6. The rotor core 2, the first end plate 4 and the second end plate 5 are all sleeved on the rotor hub 1.

[0039] As shown in Figures 1 to 3, the rotor core 2 can be annular, and the rotor core 2 can be provided with a magnetic steel slot 21. Multiple magnetic steel slots 21 can be provided along the circumferential direction C of the rotor core 2. The magnet 3 is installed in the magnetic steel slot 21. There is a gap between the magnet 3 and the wall of the magnetic steel slot 21 (especially the end wall of the magnetic steel slot 21 in the longitudinal direction). The gap forms a cooling channel. The cooling oil can flow along the cooling channel to dissipate heat for the rotor assembly, so that the rotor core 2 does not need to be processed with a separate oil channel. The cooling channel can be formed by using the magnetic steel slot, simplifying the processing process. It can be understood that the present application is not limited to this. In other possible embodiments, additional oil channels can be provided at a portion of the rotor core 2 separated from the magnetic steel 3.

[0040] The rotor core 2 may include a plurality of core segments stacked along the axial direction A of the motor, and adjacent core segments may be staggered at a certain angle in the circumferential direction C. Such a rotor assembly may be referred to as a skewed-pole rotor. Since the staggered angles of adjacent core segments are small, the cooling channels of two adjacent core segments may be connected even though they are not completely aligned, thereby forming a cooling channel that runs through the rotor core 2 along the axial direction A. Multiple cooling channels may be provided along the circumferential direction C of the rotor core 2. It will be understood that the rotor assembly or rotor of the present application does not necessarily have to be a skewed-pole rotor.

[0041] As shown in Figures 3 and 9, the cooling channel includes a first cooling channel 211 and a second cooling channel 212. The first cooling channel 211 can be located radially outside the second cooling channel 212. Specifically, the magnetic steel slot 21 can be V-shaped, with the tip of the V pointing to the radial inside of the rotor core 2, and the forked end of the V pointing to the radial outside of the rotor core 2. Two or two groups of magnetic steels 3 are installed in each V-shaped magnetic steel slot 21. The forked end of the V forms the first cooling channel 211, and the tip of the V forms the second cooling channel 212. Each V-shaped magnetic steel slot 21 can form two first cooling channels 211 and one second cooling channel 212. The first cooling channel 211 can be close to the outer peripheral surface of the rotor core 2, so that the setting of the cooling channel does not affect the radial size of the rotor core 2, and the motor structure can be compact.

[0042] As can be seen from Figures 4 and 5 , multiple magnets (a group of magnets) can be placed in one fork of a V-shaped magnet slot 21. In the illustrated example, six magnets are placed in one magnet slot 21 of one core segment. However, this is merely exemplary and not restrictive.

[0043] It is understood that the shape of the magnetic steel slot and the location of the cooling channel of the present application are not limited to this. The main purpose of the present application includes forming a flow channel in the magnetic steel slot that contacts the magnetic steel, so that the fluid (coolant or cooling oil) in the flow channel can directly contact the magnetic steel to cool the magnetic steel.

[0044] It can be understood that in the axial direction A of the rotor assembly, the first cooling channel 211 and the second cooling channel 212 may not extend completely in a straight line. Since the multiple core segments of the rotor core 2 can be staggered at a certain angle in the circumferential direction C, the first cooling channel 211 and the second cooling channel 212 can both have inflection points, but the first cooling channel 211 and the second cooling channel 212 as a whole still pass through the rotor core 2 along the axial direction A of the rotor core 2.

[0045] The magnetic steel slot 21 can be provided with a limiting protrusion 213. The limiting protrusion 213 and the elastic body 6 are located at both ends of the magnetic steel 3. The elastic body 6 can be disposed within the magnetic steel slot 21. The elastic body 6 can be squeezed and deformed by the magnetic steel 3, and the elastic body 6 allows the magnetic steel 3 to abut against the limiting protrusion 213. The limiting protrusion 213 thus creates a gap between the magnetic steel 3 and the wall of the magnetic steel slot 21 (see the radially outer end wall in Figure 9). The elastic body 6 can be formed by bending a metal sheet, with the thickness of the elastic body 6 perpendicular to the axial direction of the rotor core 3. This ensures that the thin sheet of elastic body 6 does not obstruct the flow of cooling oil through the cooling channel.

[0046] The elastic body 6 can be in the form of a sheet with curled ends. The elastic body 6 can be located at the tip of the V-shape, and the limiting protrusion 213 can be located at the bifurcated end of the V-shape. One elastic body 6 can support two or two groups of magnets 3 in the V-shaped magnet groove 21. Using the elastic body 6 to secure the magnets 3 eliminates the need for glue, and the magnet groove 21 itself can form a cooling channel, allowing the cooling oil to directly contact the magnets 3, achieving better cooling effect.

[0047] It will be appreciated that the elastic body 6 of the present application is not limited to the above-described shape. In other possible embodiments, the elastic body can be roughly V-shaped and include a metal sheet protruding toward the inside of the V, bent to form two protrusions, which can support the magnetic steel. The two forked ends of the V can be clamped between the rotor core (the sidewalls of the magnetic steel slot) and the magnetic steel.

[0048] The elastic body 6 may be formed by bending and / or curling a sheet, and the cooling oil may pass through the elastic body 6 along the axial direction A.

[0049] In other possible implementations, the elastic sheet may not be provided. For example, the radially inner end of the magnet may be supported by the protrusion of the rotor core. In another possible implementation, glue may be applied to the side surfaces of the magnet away from its longitudinal ends (radially inner and outer ends) (i.e., the surfaces that contact the side walls of the magnet slots).

[0050] As shown in Figure 2, the rotor hub 1 may be cylindrical and provided with oil inlet holes that may extend through the outer circumferential wall of the rotor hub 1. The oil inlet holes include a first oil inlet hole 11 and a second oil inlet hole 12, which are spaced apart in the axial direction A of the rotor hub 1. A plurality of first oil inlet holes 11 and a plurality of second oil inlet holes 12 are provided, with the plurality of first oil inlet holes 11 and the plurality of second oil inlet holes 12 arranged along the circumferential direction C of the rotor hub 1. When the rotor assembly rotates, cooling oil on the radially inner side of the rotor hub 1 can pass through the first oil inlet holes 11 and the second oil inlet holes 12 due to centrifugal force.

[0051] The iron core segments at both axial ends of the rotor core 2 may be staggered at a certain angle, and the first oil inlet hole 11 and the second oil inlet hole 12 may be staggered in the circumferential direction C of the rotor assembly.

[0052] As shown in Figures 1, 2, 6 to 8, the first end plate 4 and the second end plate 5 are both annular, and are respectively arranged at the axial ends of the rotor core 2. The first end plate 4 and the second end plate 5 are both tightly fitted to the rotor core 2.

[0053] As shown in Figures 4 and 7, a first oil guide groove 41 is provided on the side of the first end plate 4 facing the rotor core 2. The first oil guide groove 41 may include a straight segment 411 and a forked segment 412, and two forked segments 412 may be provided. One end of the straight segment 411 may extend to the inner periphery of the first end plate 4. The first oil inlet hole 11 and the first end plate 4 are located at the same axial position, connecting the first oil inlet hole 11 and the first oil guide groove 41. The first oil inlet hole 11 is used to guide cooling oil to the first oil guide groove 41 of the first end plate 4. The other end of the straight segment 411 may be connected to the forked segment 412. The straight segment 411 and the two forked segments 412 may form a Y shape. The two forked segments 412 may be aligned with the two first cooling channels 211 formed by the two adjacent forked ends of two adjacent V-shaped magnetic steel slots 21, respectively, to connect the first oil guide groove 41 and the first cooling channel 211.

[0054] A plurality of first oil guiding grooves 41 may be provided, and the plurality of first oil guiding grooves 41 are independent of each other and not interconnected, so that the first cooling channel 211 can be cooled independently.

[0055] It is understood that the shape of the first oil guide groove 41 is not limited thereto. For example, a separate oil guide groove may be provided for each first cooling channel 211 .

[0056] The first end plate 4 is further provided with second oil outlet holes 42, which penetrate the first end plate 4 along the axial direction A. The second oil outlet holes 42 can be aligned with the second cooling channels 212. The number of second oil outlet holes 42 and the second cooling channels 212 can be the same, and the second oil outlet holes 42 are directly opposite the second cooling channels 212.

[0057] As shown in Figures 5 and 8 , a second oil guide groove 51 is provided on the side of the second end plate 5 facing the rotor core 2. This second oil guide groove 51 can extend to the inner circumference of the second end plate 5. The second oil inlet hole 12 and the second end plate 5 are located at the same axial position, connecting the second oil inlet hole 12 and the second oil guide groove 51. The second oil inlet hole 12 is used to guide cooling oil to the second oil guide groove 51 of the second end plate 5. Multiple second oil guide grooves 51 can be provided, each independent and disconnected, allowing the second cooling channel 212 to be cooled independently.

[0058] The second end plate 5 is further provided with a first oil outlet hole 52, which penetrates the second end plate 5 along the axial direction A. The first oil outlet hole 52 can be aligned with the first cooling channel 211. The number of first oil outlet holes 52 can be half the number of first cooling channels 211, and two first cooling channels 211 can be connected to one first oil outlet hole 52.

[0059] The unidirectional arrows in Figures 4 and 5 indicate the flow direction of the cooling oil. Two sets of oil channels are formed within the rotor assembly. One set includes the interconnected first oil inlet 11, first oil guide groove 41, first cooling oil passage 211, and first oil outlet 52; the other set includes the interconnected second oil inlet 12, second oil guide groove 51, second cooling oil passage 212, and second oil outlet 42.

[0060] Cooling oil flows through the rotor core in opposite directions along the axial direction A of the rotor assembly via two sets of oil channels, cooling the rotor core. The cooling oil directly contacts the magnets 3 and rotor core 2, achieving a superior cooling effect. This superior cooling effect also reduces the need for magnet grades, thereby saving costs.

[0061] Of course, the present application is not limited to the above embodiments. Those skilled in the art can make various modifications to the above embodiments of the present application under the guidance of the present application without departing from the scope of the present application.

[0062] (1) In the above embodiment, the cooling channels are located at the tip and bifurcation of the V-shaped magnetic steel slot. However, the present application does not limit the location and number of the cooling channels. A cooling channel may be formed in other parts of the magnetic steel slot, for example, by leaving a gap between the magnet and the side wall of the magnetic steel slot.

[0063] (2) In the above embodiment, the magnetic steel groove is V-shaped, however, the present application is not limited thereto, and magnetic steel grooves of other shapes can also leave a gap between the wall of the magnetic steel groove and the magnet installed therein, thereby forming a cooling channel.

[0064] (3) In the above embodiment, the rotor assembly forms two sets of oil channels, which flow in opposite directions within the rotor core. However, the present application is not limited thereto. Alternatively, only one set of oil channels may be provided, allowing cooling oil to flow in a single direction within the rotor core. For example, oil guide grooves may be provided only in the first end plate 4 or the second end plate 5. In particular, a single end plate may provide cooling oil to different cooling channels (e.g., the first cooling channel and the second cooling channel).

[0065] (4) It is understood that the rotor core does not necessarily need to be supported by the rotor hub. The rotor core can also be supported directly or indirectly by the rotor shaft. For example, an oil inlet hole can be provided in the rotor shaft. In this case, the rotor shaft can be a hollow shaft (including a case where the rotor shaft is hollow for part of its length).

[0066] It should be understood that at least some aspects or features of the above-mentioned embodiments, examples or examples may be appropriately combined.

[0067] It is understood that in this application, when the number of parts or components is not specifically limited, the number may be one or more, and the term "plurality" herein refers to two or more. Where the number of parts or components is shown in the drawings and / or described in the specification as a specific number, such as two, three, or four, the specific number is generally illustrative and not restrictive, and may be understood as a plurality, i.e., two or more. However, this does not mean that this application excludes the case of one.

[0068] In this application, unless otherwise clearly stated or limited, terms such as "install", "assemble", "connect", "connect", "couple", "link", "abut", "connect", "interconnect", "communicate", "conduct", "fix", "fasten", etc. should be understood in a broad sense, for example, they can be direct or indirect. For example, with respect to connection, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly stated or limited. For example, with respect to connectivity / conduction, it can be direct connectivity / conduction or indirect connectivity / conduction through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0069] In the present application, unless otherwise clearly stated or limited, a component provided on / installed on / located on / accommodated on / placed in, within, inside, etc. another component may be any of the following two situations: a part or most of the one component is located in the other component; and the one component is completely accommodated in the other component.

[0070] While the present application has been described in detail using the above-described embodiments, it will be apparent to those skilled in the art that the present application is not limited to the embodiments described in this specification. The present application can be modified and implemented as modified embodiments without departing from the subject matter and scope of the present application as defined by the claims. Therefore, the descriptions in this specification are for illustrative purposes only and do not have any limiting meaning with respect to the present application.

[0071] Reference Signs List 1 Rotor hub 11 First oil inlet hole 12 Second oil inlet hole 2 Rotor core 21 Magnetic steel groove 211 First cooling channel 212 Second cooling channel 213 Position limiting protrusion 3 Magnetic steel 4 First end plate 41 First oil guide groove 411 Straight segment 412 Forked segment 42 Second oil outlet hole 5 Second end plate 51 Second oil guide groove 52 First oil outlet hole 6 Elastomer A Axial direction C Circumferential direction

Claims

1. A motor rotor cooling structure, comprising: A rotor core (2), wherein the rotor core (2) is provided with a magnetic steel slot (21); A magnetic steel (3), the magnetic steel (3) being installed in the magnetic steel slot (21), a gap being left between the magnetic steel (3) and a wall of the magnetic steel slot (21), the gap forming a cooling channel, the cooling channel penetrating the rotor core (2) along the axial direction (A) of the rotor core (2), the cooling oil passing through the cooling channel being able to directly contact the magnetic steel (3), the cooling channel comprising a first cooling channel (211) and a second cooling channel (212), the first cooling channel (211) being located radially outside the second cooling channel (212); a first end plate (4), the first end plate (4) being arranged at one axial end of the rotor core (2), the first end plate (4) being in contact with the rotor core (2), a first oil guide groove (41) being arranged on an end surface of the first end plate (4) facing the rotor core (2), the first oil guide groove (41) being in communication with the first cooling channel (211), and a second end plate (5), the second end plate (5) being arranged at the other axial end of the rotor core (2), the second end plate (5) being in contact with the rotor core (2), the second end plate (5) being provided with a first oil outlet hole (52), the first oil outlet hole (52) being in communication with the first cooling channel (211), The end surface of the second end plate (5) facing the rotor core (2) is provided with a second oil guide groove (51), the second oil guide groove (51) is communicated with the second cooling channel (212), the first end plate (4) is provided with a second oil outlet hole (42), the second oil outlet hole (42) is communicated with the second cooling channel (212), In the first cooling flow channel (211) and the second cooling flow channel (212), cooling oil can flow in opposite directions.

2. The motor rotor cooling structure according to claim 1, characterized in that: The motor rotor cooling structure further comprises a rotor hub (1) or a rotor shaft, the rotor core (2), the first end plate (4) and the second end plate (5) are sleeved on the rotor hub (1) or the rotor shaft, The rotor hub (1) or the rotor shaft is provided with a first oil inlet hole (11) and a second oil inlet hole (12), the first oil inlet hole (11) and the second oil inlet hole (12) both pass through the peripheral wall of the rotor hub (1) or the rotor shaft, the first oil inlet hole (11) and the second oil inlet hole (12) are spaced apart in the axial direction (A) of the rotor hub (1) or the rotor shaft, The first oil inlet hole (11) is in communication with the first oil guide groove (41), and the second oil inlet hole (12) is in communication with the second oil guide groove (51).

3. The motor rotor cooling structure according to claim 1, characterized in that: The magnetic steel slot (21) is V-shaped, and two or two groups of magnetic steels (3) are installed in the V-shaped magnetic steel slot (21), the tip of the V-shape points to the radial inner side of the rotor core (2), and the forked end of the V-shape points to the radial outer side of the rotor core (2), the first cooling channel (211) is located at the forked end of the V-shape, and the second cooling channel (212) is located at the tip of the V-shape.

4. The motor rotor cooling structure according to claim 1, characterized in that: The first oil guide groove (41) comprises a straight section (411) and two forked sections (412), one end of the straight section (411) extends to the inner periphery of the first end plate (4), the other end of the straight section (411) is connected to the forked section (412), and the two forked sections (412) are each connected to one of the first cooling channels (211).

5. The motor rotor cooling structure according to claim 3, characterized in that: The two bifurcated sections (412) are respectively connected to two adjacent bifurcated ends of two adjacent V-shaped magnetic steel grooves (21).

6. The motor rotor cooling structure according to claim 1, characterized in that: The first oil guide groove (41) is not connected to the second cooling channel (212), and the second oil guide groove (51) is not connected to the first cooling channel (211).

7. The motor rotor cooling structure according to claim 1, characterized in that: A plurality of the first oil guide grooves (41) are provided, and the plurality of the first oil guide grooves (41) are independent of each other and are not interconnected. A plurality of the second oil guiding grooves (51) are provided, and the plurality of the second oil guiding grooves (51) are independent of each other and are not interconnected.

8. The motor rotor cooling structure according to claim 1, characterized in that: The motor rotor cooling structure further comprises an elastic body (6), wherein the elastic body (6) is arranged between the radial inner wall of the magnetic steel slot (21) and the magnetic steel (3), so that a gap is formed between the magnetic steel (3) and the radial inner wall of the magnetic steel slot (21), and the elastic body (6) is formed by bending and / or curling a sheet material, so that the gap can allow cooling oil to pass through.

9. The motor rotor cooling structure according to claim 8, characterized in that: The magnetic steel groove (21) is provided with a limiting protrusion (213), the limiting protrusion (213) and the elastic body (6) are located at two ends of the magnetic steel (3), the elastic body (6) makes the magnetic steel (3) abut against the limiting protrusion (213), and the limiting protrusion (213) leaves a gap between the magnetic steel (3) and the radial outer side wall of the magnetic steel groove (21).

10. A motor, characterized in that: The invention comprises the motor rotor cooling structure according to any one of claims 1 to 9.

Images