CN117154982A - Oil cooling system for motor rotor - Google Patents

Abstract

The invention provides an oil cooling system for a motor rotor, which comprises a rotor shaft, a balance disc and an iron core group, wherein an inner hole is formed in one end of the rotor shaft, and two groups of oil holes penetrating into the inner hole are formed in the side wall of the rotor shaft; the two balance discs are respectively connected to the side wall of the rotor shaft, provided with two groups of oil holes, and provided with an inlet oil groove communicated with the oil holes and a penetrating outlet oil groove; an oil duct is axially formed in the iron core unit in the iron core group and is communicated with an inlet oil groove and an outlet oil groove of two balance discs at two ends of the iron core unit; the cooling oil entering the inner hole enters an inlet oil groove of the balance disc along the oil hole of the rotor shaft, then enters an oil passage of the iron core through the inlet oil groove, and finally flows out along the oil passage through an outlet oil groove. According to the invention, the cooling oil enters the iron core group in the motor rotor to cool, and the cooling oil flows in opposite directions or in the same direction in the symmetrical oil paths of the motor rotor structure, so that the problem that the cooling oil is introduced into the motor rotor and is sufficiently cooled is solved.

Description

Oil cooling system for motor rotor

Technical Field

The invention relates to the technical field of motors, in particular to an oil cooling system for a motor rotor.

Background

At present, passenger cars enter an electric age, and an oil-cooled motor has become one of the main technical directions of electric car driving systems. In the past, bridge motors of passenger cars cool and dissipate heat through a water channel outside a motor shell, so that the heat resistance is large, and the heat dissipation effect is general. The motor oil cooling is to directly flow the cooled lubricating oil from the inside of the motor and spray the lubricating oil onto the surface of the motor, so that the thermal resistance is reduced, the heat dissipation area is increased, the cooling effect is better, and the bridge performance is better.

For a permanent magnet synchronous motor, permanent magnet steel in a motor rotor is one of thermal bottlenecks, and the significance is great in order to fully utilize the advantage of oil cooling and realize that cooling oil is led into the rotor to fully cool the rotor.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, the present invention provides an oil cooling system for a motor rotor, which is configured to cool an iron core set in the motor rotor by opening an oil path in the motor rotor structure, and the cooling oil flows in a symmetrical oil path in the motor rotor structure, so as to solve the problem of guiding the cooling oil into the motor rotor for cooling and fully cooling the motor rotor by the cooling oil.

The invention provides an oil cooling system for a motor rotor, which comprises a rotor shaft, a balance disc and an iron core group, wherein an inner hole is formed in one end of the rotor shaft, and two groups of oil holes penetrating through the rotor shaft are formed in the side wall of the inner hole; the two balance discs are respectively connected to the side wall of the rotor shaft, provided with two groups of oil holes, and provided with an inlet oil groove communicated with the oil holes and an outlet oil groove penetrating through the balance discs; the iron core group is arranged on the circumferential outer side of the rotor shaft in a surrounding manner and is positioned between the two balance discs, two ends of the iron core group are respectively connected with the two balance discs, a plurality of oil channels are arranged in the iron core group, and the oil channels are communicated with an inlet oil groove and an outlet oil groove of the two balance discs at two ends of the iron core single body; the cooling oil entering the inner hole enters an inlet oil groove of the balance disc along an oil hole of the rotor shaft, then enters an oil passage of the iron core group through the inlet oil groove, and finally flows out through an outlet oil groove along the oil passage; and the same end of the adjacent oil duct is respectively communicated with the inlet oil groove and the outlet oil groove, or respectively communicated with the two inlet oil grooves or the two outlet oil grooves, so that the cooling oil can flow in opposite directions and also can flow in the same direction in the adjacent oil duct.

In an embodiment of the invention, two groups of oil holes are uniformly arranged on the side wall of the inner hole of the rotor shaft, and the number of the oil holes is equal to the number of iron core monomers in the iron core group; the angle difference between any adjacent oil holes in the two groups of oil holes is equal in the circumferential angle of the rotor shaft.

In an embodiment of the present invention, on a single balance disc at one end of the core pack, the same number of inlet oil grooves and outlet oil grooves are alternately arranged, and the sum of the numbers of the inlet oil grooves and the outlet oil grooves is equal to the number of the core units.

In an embodiment of the present invention, at least one oil passage is formed in the core unit, and the plurality of oil passages are circumferentially symmetrical with respect to the core group.

In an embodiment of the present invention, when the number of oil channels of the core unit is an odd number, the inlet oil groove and the outlet oil groove are respectively located at two ends of the core unit; when the number of the oil ducts of the iron core monomers is even, the inlet oil groove and the outlet oil groove are positioned at the same end of the iron core monomers.

In an embodiment of the present invention, when the number of oil channels of the core unit is greater than one, the balance disc is further provided with a loop oil groove, and the loop oil groove is communicated with adjacent oil channels of the core unit.

In an embodiment of the invention, an end of the outlet oil groove facing away from the core pack faces the stator end winding of the motor.

In an embodiment of the present invention, in the core pack, on balance discs at two ends of at least one pair of core units, which are axisymmetric, when the inlet oil groove and the outlet oil groove are located at the same end of the core unit; the balance disc is positioned at one end of the iron core monomer, and the end part of the outlet oil groove, which is back to the iron core monomer, is closed and communicated with the inlet oil groove; the balance disc is positioned at the other end of the iron core monomer, and the loop oil groove is provided with an outlet oil groove; so as to change the number of outlet oil grooves at two ends of the iron core group.

In an embodiment of the present invention, in the core pack, on balance discs at two ends of at least one pair of core monomers, which are axisymmetric, when the inlet oil groove and the outlet oil groove are respectively located at two ends of the core monomers; the balance disc is positioned at one end of the iron core unit, and the outlet oil groove is closed at the end part of the iron core unit, which is opposite to the iron core unit, and is communicated with the loop oil groove; the balance disc is arranged at the other end of the iron core monomer, is provided with an outlet oil groove, and is communicated with the outlet oil groove or the inlet oil groove; so as to change the number of outlet oil grooves at two ends of the iron core group.

In an embodiment of the present invention, the two groups of oil holes are axially symmetrically arranged on two axial sections of the rotor shaft, and the number of the oil holes is different, and the angle difference between any adjacent oil holes in the two groups of oil holes is equal in the circumferential angle of the rotor shaft.

The invention has the beneficial effects that: through the oil circuit of seting up in the motor rotor structure, make the cooling oil get into the inside iron core group of motor rotor and cool off to reinforcing the cooling effect to motor rotor, and the cooling oil flows in the symmetrical oil circuit of motor rotor structure, makes the cooling effect more even, through the oil circuit export quantity of adjusting motor rotor structure simultaneously, the balanced cooling oil flow to the flow of rotor both ends stator winding.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention. It is evident that the drawings in the following description are only some embodiments of the present invention and that other drawings may be obtained from these drawings without inventive effort for a person of ordinary skill in the art. In the drawings:

FIG. 1 is a schematic view of a motor rotor structure according to the present invention;

FIG. 2 is a schematic view of the oil circuit structure of the various parts of the motor rotor of the present invention;

FIG. 3 is a schematic diagram of the internal oil circuit of the motor rotor according to the present invention;

FIG. 4 is a schematic view of the motor rotor structure of the present invention in an oil circuit extended state;

fig. 5 (a) and (b) are schematic structural diagrams of the motor rotor structure of the present invention in an unfolded state at different numbers of oil circuit groups;

fig. 6 (a), (b) and (c) are schematic structural diagrams of the motor rotor structure of the present invention in an unfolded state when the outlet direction of the oil path is changed;

fig. 7 is a schematic view showing a rotor structure of the motor according to the present invention in an unfolded state when the number of oil holes of the rotor shaft is changed.

In the figure: 1. a rotor shaft; 10. an inner bore; 11. an oil hole; 2. a balancing disk; 21. an inlet oil sump; 22. an outlet oil groove; 23. a loop oil groove; 3. an iron core group; 30. an iron core single body; 31. an oil passage.

Detailed Description

Other advantages and effects of the present invention will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present invention with reference to specific examples. The invention may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present invention. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict. It is also to be understood that the terminology used in the examples of the invention is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the invention. The test methods in the following examples, in which specific conditions are not noted, are generally conducted under conventional conditions or under conditions recommended by the respective manufacturers.

Please refer to fig. 1 to 7. It should be understood that the structures, proportions, sizes, etc. shown in the drawings are for illustration purposes only and should not be construed as limiting the invention to the extent that it can be practiced, since modifications, changes in the proportions, or otherwise, used in the practice of the invention, are not intended to be critical to the essential characteristics of the invention, but are intended to fall within the spirit and scope of the invention. Also, the terms such as "upper," "lower," "left," "right," "middle," and "a" and the like recited in the present specification are merely for descriptive purposes and are not intended to limit the scope of the invention, but are intended to provide relative positional changes or modifications without materially altering the technical context in which the invention may be practiced.

Referring to fig. 1 to 6, the invention provides an oil cooling system for a motor rotor, which comprises a rotor shaft 1, a balance disc 2 and an iron core set 3, wherein an inner hole 10 is formed at one end of the rotor shaft 1, and two groups of oil holes 11 penetrating through the side wall of the inner hole 10 are formed in the rotor shaft 1; the two balance discs 2 are respectively connected to the side wall of the rotor shaft 1, provided with two groups of oil holes 11, and the balance discs 2 are provided with an inlet oil groove 21 communicated with the oil holes 11 and an outlet oil groove 22 penetrating through the balance discs 2; the iron core group 3 is arranged on the circumferential outer side of the rotor shaft 1 in a surrounding manner and is positioned between the two balance discs 2, two ends of the iron core group 3 are respectively connected with the two balance discs 2, a plurality of oil channels 31 are arranged in the iron core group 3, and the oil channels 31 are communicated with the inlet oil grooves 21 and the outlet oil grooves 22 of the two balance discs 2 at two ends of the iron core single body 30; the cooling oil entering the inner hole 10 enters the inlet oil groove 21 of the balance disc 2 along the oil hole 11 of the rotor shaft 1, then enters the oil duct 31 of the iron core group 3 through the inlet oil groove 21, and finally flows out along the oil duct 31 through the outlet oil groove 22; and the same ends of the adjacent oil passages 31 are respectively communicated with the inlet oil groove 21 and the outlet oil groove 22, or respectively communicated with the two inlet oil grooves 21 or the two outlet oil grooves 22, so that the cooling oil can flow in opposite directions or in the same direction in the adjacent oil passages 31.

Further, on the single balance disc 2 at one end of the core pack 3, the same number of inlet oil grooves 21 and outlet oil grooves 22 are alternately arranged, and the sum of the number of inlet oil grooves 21 and outlet oil grooves 22 is equal to the number of core units 30.

In the present embodiment, the cooling oil path of the motor rotor is provided in the rotor shaft 1, the left and right balance plates 2, and the core group 3 of the motor rotor of the motor. The iron core unit 30 of the iron core group 3 is embedded with magnetic steel and can be designed for four pairs of eight poles. As shown in fig. 2, four oil inlet grooves 21 are formed in the inner sides (the side contacting the iron core single body 30) of the left and right balance discs 2, and are matched with the iron core single body 30 to form a closed balance disc 2 oil path, the oil path inlets of the oil inlet grooves 21 are aligned with the oil holes 11 of the rotor shaft 1, and the outlets of the oil inlet grooves 21 are aligned with the oil paths 31 on the iron core single body 30. So that the cooling oil flows out from the oil hole 11 of the rotor shaft 1 and then flows into the core unit 30 of the rotor through the inlet oil groove 21 of the balance disc 2.

As shown in fig. 2, two groups of oil channels 31 with different shapes are formed in the center of the iron core unit 30, which is close to the iron core group 3, and are uniformly and symmetrically distributed at intervals in the circumferential direction. As shown in fig. 3 and 4, the cooling oil flows out from the inlet oil grooves 21 of the balance discs 2 on both sides, flows into one group of oil holes 11 in the iron core group 3, flows out from the right side of the left side, the left side of right side inflow flows out, and the magnetic steel embedded in the iron core group 3 is cooled along the oil ducts 31 alternately arranged in the iron core monomers 30.

It should be noted that, in the adjacent oil passages 31, the cooling oil is caused to flow in opposite directions, and the same number of inlet oil grooves 21 and outlet oil grooves 22 may be formed on the balance discs 2 at both ends of the core pack 3; in the adjacent oil channels 31, the cooling oil flows in the same direction, so that different numbers of inlet oil grooves 21 and outlet oil grooves 22 can be formed on the balance discs 2 at two ends of the iron core group 3, and further, the inlet oil grooves 21 and the outlet oil grooves 22 with different interception areas are formed on the balance discs 2 at two ends of the iron core group 3, so that flow parameters of the cooling oil in the balance discs 2 at two ends are correspondingly adjusted to adapt to the requirements of working conditions.

It should be noted that the magnetic pole order of the core units 30 in the core group 3 is not limited, that is, the arrangement of N, S … … N, S may be replaced by S, N … … S, N, and the oblique pole design is not shown in the core group 3, but the present solution is not limited thereto, and may also include a corresponding design, which is not described herein. The cross-sectional shapes of the oil holes 11, the oil grooves, and the oil passages 31 are not limited to the rotor shaft 1, the balance disc 2, and the core unit 30, and may be any other shape so as to satisfy the requirement of forming a cooling oil passage. Meanwhile, in order to obtain better cooling performance, the shape and the structure of the oil way can be correspondingly adjusted.

Optionally, the positions of the first set of oil channels 31 and the second set of oil channels 31 formed on the core unit 30 are not limited, and may be any other positions, including, but not limited to, a large magnetic steel groove, a small magnetic steel groove, a position close to the magnetic steel, and the like. Referring to fig. 5, a third set of oil channels 31 may be added to the core unit 30, or only one set of oil channels 31 may be added, and the shape and position of the oil channels 31 are the same as the above requirements.

Similarly, the present embodiment is equally applicable to a three-pair six-pole rotor except for the four-pair eight-pole iron core set 3, and the number of the oil holes 11, the oil grooves, and the oil passages 31 in each component in the rotor may correspond to the number of poles of the rotor. In addition, the cooling oil path in the present embodiment is also applicable to an asynchronous motor, or an electrically excited motor, in addition to a permanent magnet synchronous motor.

Referring to fig. 2, in an embodiment, two groups of oil holes 11 are uniformly arranged on the side wall of the inner hole 10 of the rotor shaft 1, and the number of the oil holes 11 is equal to the number of the core units 30 in the core group 3; in the circumferential angle of the rotor shaft 1, the angle difference between any adjacent oil holes 11 in the two groups of oil holes 11 is equal.

In the present embodiment, the cooling oil flows from the end of the rotor shaft 1 into the inner bore 10 of the rotor shaft 1. The rotor shaft 1 is provided with oil holes 11 at two sections matched with the left and right balance discs 2, as shown in fig. 2, each section is symmetrically provided with four oil holes 11, an included angle between each oil hole 11 is 90 degrees, and two groups of oil holes 11 on the two sections have an angle difference of 45 degrees. The cooling oil entering the inner bore 10 of the rotor shaft 1 flows into the inlet oil groove 21 of the balance disc 2 through the two groups of oil holes 11. Through the oil holes 11 symmetrically distributed on the rotor shaft 1, the cooling oil enters into each iron core unit 30 uniformly along the left and right balance plates 2 at the two ends of the iron core group 3 after entering into the inlet oil grooves 21 in the balance plates 2.

Referring to fig. 4 to 5, in an embodiment, at least one oil passage 31 is formed in the core unit 30, and the plurality of oil passages 31 are circumferentially symmetrical with respect to the core set 3. That is, in the drawing, the oil passage 31 marked in the core unit 30 may be represented by only one oil passage marked as the track of the oil passage 31 or a plurality of oil passages marked as the track of the oil passage 31 in the core unit 30, which is not limited herein. Similarly, it may be understood that the oil path in the core unit 30 may be formed by one oil path 31 or may be formed by a plurality of oil paths 31, and the number is not limited, but the whole needs to ensure a circumferentially symmetrical relationship, so as to satisfy the effect of balanced cooling and maintain the stability of the rotor structure in operation.

Referring to fig. 4 to 5, in an embodiment, when the number of oil channels 31 of the core unit 30 is an odd number, the inlet oil grooves 21 and the outlet oil grooves 22 are respectively located at two ends of the core unit 30; when the number of the oil passages 31 of the core unit 30 is even, the inlet oil groove 21 and the outlet oil groove 22 are located at the same end of the core unit 30. When the number of the oil channels 31 of the iron core single body 30 is more than one, the balance disc 2 is also provided with a loop oil groove 23, and the loop oil groove 23 is communicated with the adjacent oil channels 31 of the iron core single body 30.

In this embodiment, when the plurality of oil passages 31 are formed in the core unit 30, in order to keep the cooling oil flowing through the oil passages of the rotor structure sufficiently, the cooling oil is circulated reciprocally along the oil passages between the core unit 30 and the balance disc 2. As shown in fig. 2, 3 and 4, after the cooling oil flows out from the first set of oil channels 31 of the iron core single body 30, the cooling oil flows into another oil channel formed by the balance disc 2 and the iron core single body 30, wherein the oil channel is formed by matching a loop oil groove 23 on the balance disc 2 with the iron core single body 30, an inlet of the loop oil groove 23 is aligned with the first set of oil channels 31 of the iron core single body 30, and an outlet of the loop oil groove 23 is aligned with an inlet of the second set of oil channels 31 of the iron core single body 30. After entering the second group of oil channels 31, the cooling oil enters from one side of the core unit 30 and flows out from the other side, and symmetrically flows (the flow directions of the cooling oil are opposite in the oil channels 31 of the adjacent core unit 30 and the adjacent oil channels 31 of the core unit 30) in opposite directions, so that the cooling of the length direction of the motor rotor is more uniform. Finally, the cooling oil flows out of the second group of oil passages 31 of the iron core single body 30 and then flows out of the rotor through the outlet oil grooves 22 of the left and right balance discs 2.

Further, the end of the outlet oil groove 22 facing away from the core pack 3 is directed towards the stator end winding of the motor. After the cooling oil in the rotor structure is thrown out, the inner side of the stator end winding is sprayed and cooled, and the cooling effect on the motor structure is maintained.

Referring to fig. 6, in one embodiment, in the core set 3, on the balance disc 2 at two ends of at least one pair of core units 30 that are axisymmetric, when the inlet oil groove 21 and the outlet oil groove 22 are located at the same end of the core unit 30; the balance disc 2 is positioned at one end of the iron core single body 30, and the end part of the outlet oil groove 22, which is opposite to the iron core single body 30, is closed and communicated with the inlet oil groove 21; the balance disc 2 is positioned at the other end of the iron core monomer 30, and the loop oil groove 23 is provided with an outlet oil groove 22; to vary the number of outlet oil grooves 22 at both ends of the core pack 3.

Further, in the core pack 3, on the balance disc 2 at both ends of at least one pair of core units 30 which are axisymmetric, when the inlet oil groove 21 and the outlet oil groove 22 are respectively located at both ends of the core units 30; the balance disc 2 is positioned at one end of the iron core monomer 30, and the end part of the outlet oil groove 22, which is opposite to the iron core monomer 30, is closed and communicated with the loop oil groove 23; the balance disc 2 is positioned at the other end of the iron core monomer 30, and the balance disc 2 is provided with an outlet oil groove 22 and a loop oil groove 23 communicated with the outlet oil groove 22 or the inlet oil groove 21; to vary the number of outlet oil grooves 22 at both ends of the core pack 3.

The cooling oil in the motor rotor oil circuit has an important function of spraying and cooling the inner side of the stator end winding after being thrown out. However, the cooling oil enters the inner hole 10 of the rotor shaft 1 in an asymmetric way, which may cause uneven oil distribution of the two groups of oil holes 11 of the rotor shaft 1, and further cause the oil sprayed by the end windings of the stator to be different. For this purpose, an axially asymmetrical oil channel 31 can be provided.

As shown in fig. 6, in this embodiment, the oil paths of the balance disc 2 that are connected in parallel to the oil paths 31 on the core unit 30 are designed through the oil paths of the balance disc 2, and the oil paths of the balance disc 2 that are connected to each other are adjusted in the pair of core units 30 that are axially symmetrical in the core group 3, for example, the oil paths of the balance disc 2 that are correspondingly connected to the second and sixth core units 30 from left to right in fig. 6. For the balance disc 2 with the inlet oil groove 21 and the outlet oil groove 22 on the same side of the iron core single body 30, the outlet oil groove 22 in the balance disc 2 can be closed and communicated with the inlet oil groove 21, and then the outlet oil groove 22 of the iron core single body 30 is opened on the loop oil groove 23 at the other end.

Similarly, according to the different numbers of the oil channels 31 in the core unit 30, when the inlet oil groove 21 and the outlet oil groove 22 on the balance disc 2, which are communicated with the core unit 30, are respectively located at different ends, the structure of the outlet oil groove 22 in the balance disc 2 is correspondingly adjusted and communicated with the loop oil groove 23, and correspondingly, the outlet oil groove 22 is re-opened at the other end, and the loop oil groove 23 at the other end is optionally communicated with the outlet oil groove 22 or the inlet oil groove 21.

For different oil path structures of the oil paths 31 in the balance disc 2, which are communicated with the iron core monomers 30, the oil path structures in the balance disc 2 are adjusted in the mode, and the two oil paths 31 in the iron core monomers 30 are connected in parallel, so that the final outflow direction of cooling oil in the iron core monomers 30 is changed, and the condition of changing the oil injection quantity of the left side and the right side of the rotor is realized. Referring to the iron core set 3 with four-to-eight pole structure in fig. 6, the number of oil outlets at two ends of the iron core set can be adjusted from 4:4 to 6:2 (or 2:6). The number of the oil outlets of the motor rotor with the corresponding three-pair six-pole structure can be adjusted to be 4:2 (or 2:4) from 3:3, so that the flow ratio of cooling oil in the final outflow direction is changed by adjusting the number of the oil outlet grooves 22 on the balance disc 2 at the two ends of the iron core group 3, the oil quantity difference when the cooling oil enters the two groups of oil holes 11 from the inner hole 10 of the rotor shaft 1 is balanced, and the balance of the spraying oil quantity of the end windings of the stator at the two ends of the rotor is maintained.

Referring to fig. 7, in an embodiment, two groups of oil holes 11 are axially symmetrically arranged on two axial sections of the rotor shaft 1, and the number of the oil holes is unequal, and the angle difference between any adjacent oil holes 11 in the two groups of oil holes 11 is equal in the circumferential angle of the rotor shaft 1.

It should be noted that, in the foregoing embodiment, the manner of changing the flow rate of the cooling oil of the balance disc 2 at the two ends of the core group 3 by connecting the two oil passages 31 in the core unit 30 in parallel may also be achieved by adjusting the number of the oil holes 11 on the rotor shaft 1. As shown in fig. 7, in the second and sixth embodiments, for example, in the scheme that two sets of oil channels 31 are formed in the core unit 30, by changing the number ratio of the two sets of oil holes 11 formed in the rotor shaft 1, the difference in oil quantity of the two sets of oil holes 11 is reduced when the cooling oil entering the inner hole 10 from one end of the rotor shaft 1 flows out through the two sets of different numbers of oil holes 11 on the rotor shaft 1 at different distances in the inner hole 10, so that the balance of the oil quantity sprayed by the cooling oil from the outlet oil grooves 22 of the balance discs 2 at both ends is maintained. Similarly, the case is similar for one and three sets of oil passages. And simultaneously, other requirements in the main scheme can be met, and details are not repeated here.

In summary, according to the oil cooling system for the motor rotor provided by the invention, through the oil way arranged in the motor rotor structure, cooling oil enters the iron core group 3 in the motor rotor to cool, so that the cooling effect on the motor rotor is enhanced, the cooling oil flows in the symmetrical oil way of the motor rotor structure, the cooling effect is more uniform, and meanwhile, the flow of the cooling oil flowing to stator windings at two ends of the rotor is balanced by adjusting the number of oil way outlets of the motor rotor structure.

The above embodiments are merely illustrative of the principles of the present invention and its effectiveness, and are not intended to limit the invention. Modifications and variations may be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the invention. Accordingly, it is intended that all equivalent modifications and variations of the invention be covered by the claims, which are within the ordinary skill of the art, be within the spirit and scope of the present disclosure.

Claims (10)

1. An electric machine rotor oil-cooled cooling system, comprising:

a rotor shaft (1), wherein an inner hole (10) is formed at one end of the rotor shaft (1), and two groups of oil holes (11) penetrating through the rotor shaft (1) are formed on the side wall of the inner hole (10);

the balance discs (2) are respectively connected to the side walls of the rotor shaft (1) provided with two groups of oil holes (11), and the balance discs (2) are provided with an inlet oil groove (21) communicated with the oil holes (11) and an outlet oil groove (22) penetrating through the balance discs (2);

the iron core group (3), the iron core group (3) is arranged on the outer side of the circumference of the rotor shaft (1) in a surrounding mode and is positioned between the two balance discs (2), a plurality of oil channels (31) are formed in the iron core group (3), and the oil channels (31) are communicated with the inlet oil grooves (21) and the outlet oil grooves (22) of the two balance discs (2) at two ends;

wherein the same end of the adjacent oil channels (31) is respectively communicated with the inlet oil groove (21) and the outlet oil groove (22), or is respectively communicated with two inlet oil grooves (21) or two outlet oil grooves (22).

2. The cooling system according to claim 1, wherein two groups of oil holes (11) are uniformly arranged on the side wall of the inner hole (10) of the rotor shaft (1) and are equal in number, and the number of oil holes (11) is equal to the number of core monomers (30) in the core group (3); in the circumferential angle of the rotor shaft (1), the angle difference between any adjacent oil holes (11) in two groups of oil holes (11) is equal.

3. A cooling system according to claim 1, characterized in that the same number of the inlet oil grooves (21) and the outlet oil grooves (22) are arranged alternately on a single balance disc (2) at one end of the core pack (3), and the sum of the number of the inlet oil grooves (21) and the number of the outlet oil grooves (22) is equal to the number of the core monomers (30).

4. A cooling system according to claim 3, characterized in that at least one of the oil channels (31) is provided in the core unit (30), and that several of the oil channels (31) are circumferentially symmetrical with respect to the core pack (3).

5. The cooling system according to claim 4, wherein when the number of the oil passages (31) of the core single body (30) is an odd number, the inlet oil grooves (21) and the outlet oil grooves (22) are located at both ends of the core single body (30), respectively;

when the number of the oil passages (31) of the core unit (30) is an even number, the inlet oil groove (21) and the outlet oil groove (22) are located at the same end of the core unit (30).

6. The cooling system according to claim 5, wherein when the number of the oil channels (31) of the core unit (30) is greater than one, a loop oil groove (23) is further formed in the balance disc (2), and the loop oil groove (23) is communicated with adjacent oil channels (31) of the core unit (30).

7. A cooling system according to claim 1, characterized in that the end of the outlet oil groove (22) facing away from the core pack (3) is directed towards the stator end winding of the electric machine.

8. The cooling system according to claim 6, wherein in the core pack (3), on the balance disc (2) at both ends of at least one pair of the core cells (30) that are axisymmetric, when the inlet oil groove (21) and the outlet oil groove (22) are located at the same end of the core cell (30); the balance disc (2) is positioned at one end of the iron core monomer (30), and the end part of the outlet oil groove (22) opposite to the iron core monomer (30) is closed and communicated with the inlet oil groove (21); the balance disc (2) is positioned at the other end of the iron core monomer (30), and the loop oil groove (23) is provided with the outlet oil groove (22); to vary the number of outlet oil grooves (22) at both ends of the core pack (3).

9. The cooling system according to claim 6, wherein in the core pack (3), at least one pair of the core units (30) that are axisymmetric are provided on the balance plate (2) at both ends thereof when the inlet oil groove (21) and the outlet oil groove (22) are respectively provided at both ends of the core unit (30); the balance disc (2) is positioned at one end of the iron core monomer (30), and the end part of the outlet oil groove (22) facing away from the iron core monomer (30) is closed and communicated with the loop oil groove (23); the balance disc (2) is positioned at the other end of the iron core monomer (30), the balance disc (2) is provided with the outlet oil groove (22), and the loop oil groove (23) is communicated with the outlet oil groove (22) or the inlet oil groove (21); to vary the number of outlet oil grooves (22) at both ends of the core pack (3).

10. Cooling system according to claim 1, characterized in that the two groups of oil holes (11) are arranged axisymmetrically in two axial sections of the rotor shaft (1) and are unequal in number, and that the angle difference between any adjacent oil holes (11) of the two groups of oil holes (11) is equal in the circumferential angle of the rotor shaft (1).