阅读说明：本技术 一种永磁电机及轨道机车 (Permanent magnet motor and rail locomotive ) 是由 张道禄 倘广垒 丰帆 刘勇 黄鹏程 晏才松 李广 杨川 王冬梅 余超 于 2021-07-15 设计创作，主要内容包括：本发明公开了一种永磁电机及轨道机车,通过第一冷却风路对壳体和定子结构冷却降温,通过第二冷却风路对转子结构和壳体降温,以及通过第三冷却风路对转子结构和壳体降温,使得安装在转轴的轴承的热量辐射至转轴和/或壳体后,热量可被第一冷却风路、第二冷却风路和第三冷却风路带走,进而起到可对电机内部进行有效降温,并避免壳体降温不及时,导致转子结构、定子结构和轴承的温度升高最终导致电机功率被限制问题出现。(The invention discloses a permanent magnet motor and a rail locomotive, wherein a shell and a stator structure are cooled through a first cooling air path, a rotor structure and a shell are cooled through a second cooling air path, and the rotor structure and the shell are cooled through a third cooling air path, so that after heat of a bearing arranged on a rotating shaft is radiated to the rotating shaft and/or the shell, the heat can be taken away by the first cooling air path, the second cooling air path and the third cooling air path, the inner part of the motor can be effectively cooled, and the problem that the temperature of the rotor structure, the stator structure and the bearing is increased to finally limit the power of the motor due to untimely cooling of the shell is avoided.)

1. A permanent-magnet machine, includes casing, stator structure and rotor structure, the stator structure with the rotor structure is located in the casing, the stator structure includes stator core (31) and stator winding (32), the rotor structure includes pivot (41) and rotor core (42), pivot (41) through the bearing install in the casing, its characterized in that, permanent-magnet machine still includes: an external cooling air passage;

the external cooling air path comprises an air inlet (13), a first cooling air path, a second cooling air path and a third cooling air path;

the air inlet (13) is formed in the shell, the first ends of the first cooling air paths are communicated with the air inlet (13), and the second ends of the first cooling air paths penetrate through the inner wall of the shell and/or the stator core (31) along a first direction;

the first end of the second cooling air path is communicated with the air inlet (13), and the second end of the second cooling air path passes through the second end of the rotating shaft (41) along a second direction and penetrates through the inner wall of the shell;

the first end of the third cooling air path is communicated with the second end of at least one first cooling air path, and the second end of the third cooling air path penetrates through the inner wall of the shell through the first end of the rotating shaft (41) along the third direction.

2. The permanent magnet electric machine of claim 1, wherein the housing comprises: the device comprises a base, a first end cover (1) and a second end cover (2);

the first end cover (1) is positioned at the first end of the base, the second end cover (2) is positioned at the second end of the base, and the base, the first end cover (1) and the second end cover (2) form a space for installing the stator structure and the rotor structure;

the first cooling air path comprises a first channel (18) arranged on the base and a second channel (19) arranged on the first end cover (1), the first channel (18) and the second channel (19) are communicated with each other, and the first channel (18) extends along the axial direction;

the third cooling air path includes a seventh passage (24), an eighth passage (25), and a ninth passage (26) provided in the first end cover (1), the seventh passage (24), the eighth passage (25), and the ninth passage (26) are sequentially communicated, and the seventh passage (24) extends in a radial direction.

3. A permanent magnet machine according to claim 2, characterized in that the eighth channel (25) communicates with the ninth channel (26) through a first ventilation gap (14), the first ventilation gap (14) being the gap formed by the second end cover (2) and the rotor structure.

4. A permanent magnet machine according to claim 2, characterized in that the seventh channel (24) is formed by a wind guiding cover (5) arranged on the first end cover (1).

5. The permanent magnet electric machine according to claim 2, characterized in that the second cooling air duct comprises a third channel (20), a fourth channel (21), a fifth channel (22) and a sixth channel (23) arranged at the second end cover (2), the third channel (20), the fourth channel (21), the fifth channel (22) and the sixth channel (23) are in communication in sequence, and the fourth channel (21), the fifth channel (22) and the sixth channel (23) all extend in a radial direction.

6. A permanent magnet machine according to claim 5, characterized in that the fifth channel (22) communicates with a sixth channel (23) through a second ventilation gap (15), the second ventilation gap (15) being the gap formed by the second end cover (2) and the rotor structure.

7. A permanent magnet machine according to claim 5, characterized in that the fourth channel (21) is formed by a wind guiding cover (5) arranged on the second end cover (2).

8. A permanent magnet motor according to claim 1, characterized in that the air inlet (13) opens into the machine base.

9. The permanent magnet electric machine of claim 1, further comprising: an internal cooling air passage and a fan (6);

the internal cooling air path is positioned in the shell, penetrates through the stator core (31), the stator winding (32) and the rotor core (42) in a closed ring shape, and is driven to circulate by the fan (6).

10. The permanent magnet motor according to claim 8, wherein the internal cooling air path comprises a rotor air duct (28), a first cavity (16), a stator air duct (27) and a second cavity (17) which are sequentially communicated, wherein the first cavity (16) is defined by a first end of the stator core (31) and a first end of the rotor core (42) and an inner wall of the housing, the second cavity (17) is defined by a second end of the stator core (31) and a second end of the rotor core (42) and an inner wall of the housing, the rotor channel (28) axially penetrates through the rotor core (42), and the stator air duct (27) axially penetrates through the stator core (31).

11. A rail vehicle comprising a permanent magnet machine according to any one of claims 1 to 10.

Technical Field

The invention relates to the field of rail vehicles, in particular to a permanent magnet motor and a rail locomotive.

Background

The permanent magnet motor is used as a main part of a rail locomotive, and in order to prevent metal powder generated by friction between wheels and steel rails during running of the rail locomotive and brake shoe ash generated by brake shoe abrasion during braking from entering the motor and being adsorbed on the surface of a rotor of the permanent magnet motor, the permanent magnet motor is required to adopt a fully closed structure.

The conventional totally-enclosed forced ventilation structure is cooled in a stator ventilation channel ventilation mode, cooling air enters the stator ventilation channel from a radial air inlet on a rear end cover or a stator base during working, and axially reaches an air outlet on a front end cover or a middle end cover along the stator ventilation channel, and is discharged out of the ventilation channel from the air outlet so as to take away heat inside a motor.

However, the conventional totally-enclosed forced ventilation cooling structure only dissipates heat through cooling air in the stator ventilation duct, so that heat inside the motor cannot be dissipated effectively, the motor is easy to become an isothermal body, the heat inside the motor is conducted, convected and radiated among all parts, the temperature of the permanent magnet and the temperature of the bearing are high, the limit values of the temperature of the winding, the temperature of the permanent magnet and the temperature of the bearing are different, and the exertion of the power of the motor is limited finally.

Disclosure of Invention

In view of this, embodiments of the present invention provide a permanent magnet motor and a rail locomotive, so as to solve the problem that the conventional fully-enclosed forced ventilation cooling structure cannot effectively dissipate heat inside the motor, so that the power of the motor is limited.

In order to achieve the above purpose, the embodiments of the present invention provide the following technical solutions:

the invention discloses a permanent magnet motor in a first aspect, which comprises a shell, a stator structure and a rotor structure, wherein the stator structure and the rotor structure are positioned in the shell, the stator structure comprises a stator core and a stator winding, the rotor structure comprises a rotating shaft and a rotor core, the rotating shaft is arranged in the shell through a bearing, and the permanent magnet motor also comprises: an external cooling air passage;

the external cooling air path comprises an air inlet, a first cooling air path, a second cooling air path and a third cooling air path;

the air inlet is formed in the shell, the first ends of the first cooling air paths are communicated with the air inlet, and the second ends of the first cooling air paths penetrate through the inner wall of the shell and/or the stator core along a first direction;

the first end of the second cooling air path is communicated with the air inlet, and the second end of the second cooling air path passes through the second end of the rotating shaft along a second direction and penetrates through the inner wall of the shell;

the first end of the third cooling air path is communicated with the second end of at least one first cooling air path, and the second end of the third cooling air path penetrates through the inner wall of the shell through the first end of the rotating shaft along the third direction.

Preferably, the housing includes: the device comprises a base, a first end cover and a second end cover;

the first end cover is positioned at the first end of the machine base, the second end cover is positioned at the second end of the machine base, and the machine base, the first end cover and the second end cover form a space for installing the stator structure and the rotor structure;

the first cooling air path comprises a first channel arranged on the base and a second channel arranged on the first end cover, the first channel and the second channel are communicated with each other, and the first channel extends along the axial direction;

the third cooling air path includes a seventh passage, an eighth passage, and a ninth passage provided in the first end cover, the seventh passage, the eighth passage, and the ninth passage are sequentially communicated, and the seventh passage extends in a radial direction.

Preferably, the eighth passage communicates with the ninth passage through a first ventilation gap, and the first ventilation gap is a gap formed between the second end cover and the rotor structure.

Preferably, the seventh passage is formed by a wind-guiding cover provided on the first end cover.

Preferably, the second cooling air path includes a third channel, a fourth channel, a fifth channel, and a sixth channel disposed in the second end cover, the third channel, the fourth channel, the fifth channel, and the sixth channel are sequentially communicated, and the fourth channel, the fifth channel, and the sixth channel all extend in a radial direction.

Preferably, the fifth channel is communicated with the sixth channel through a second ventilation gap, and the second ventilation gap is a gap formed between the second end cover and the rotor structure.

Preferably, the fourth channel is formed by a wind cap provided on the second end cap.

Preferably, the air inlet is formed in the base.

Preferably, the method further comprises the following steps: an internal cooling air passage and a fan;

the internal cooling air path is located inside the shell and penetrates through the stator core, the stator winding and the rotor core in a closed ring shape, and air in the internal cooling air path is driven to circulate by the fan.

Preferably, the internal cooling air path includes a rotor air duct, a first cavity, a stator air duct, and a second cavity, which are sequentially connected to each other, where the first cavity is defined by a first end of the stator core and a first end of the rotor core and an inner wall of the housing, the second cavity is defined by a second end of the stator core and a second end of the rotor core and an inner wall of the housing, the rotor passage axially penetrates through the rotor core, and the stator air duct axially penetrates through the stator core.

The invention discloses a rail locomotive in a second aspect, and the rail locomotive comprises the permanent magnet motor disclosed in the first aspect of the invention.

According to the permanent magnet motor and the rail locomotive, the first end of the first cooling air path is communicated with the air inlet, and the second end of the first cooling air path penetrates through the inner wall of the shell along the first direction, so that air entering through the air inlet enters the first cooling air path, and the inner wall of the shell and the stator core are cooled along the first direction, and further a certain cooling effect is achieved on the bearing; the first end of the second cooling air path is communicated with the air inlet, the second end penetrates through the inner wall of the shell along the second direction, so that the air entering from the air inlet enters the second cooling air path, the inner wall of the shell and the rotor structure are cooled along the second direction, a certain cooling effect is further exerted on the bearing, the first cooling air paths are multiple, the first end of the third cooling air path is communicated with the second end of the first cooling air path, the second end of the third cooling air path penetrates through the inner wall of the shell along the third direction, so that the air discharged from the first cooling air path enters the third cooling air path and cools the inner wall of the shell along the third direction, the shell and the rotor structure are cooled through the first cooling air path, the second cooling air path and the third cooling air path, and the interior of the motor can be effectively cooled by matching with the internal cooling of the air paths, and then avoid the casing cooling untimely, lead to rotor structure and stator structure's temperature rising to lead to motor power to be restricted the problem to appear.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a permanent magnet motor according to an embodiment of the present invention.

The air conditioner comprises a first end cover 1, a second end cover 2, a stator core 31, a stator winding 32, a rotating shaft 41, a rotor core 42, an air inducing cover 5, a fan 6, a first bearing 7, a second bearing 8, a first end cover annular boss 9, a second end cover annular boss 10, a third end cover annular boss 11, a fourth end cover annular boss 12, an air inlet 13, a first ventilation gap 14, a second ventilation gap 15, a first cavity 16, a second cavity 17, a first channel 18, a second channel 19, a third channel 20, a fourth channel 21, a fifth channel 22, a sixth channel 23, a seventh channel 24, an eighth channel 25, a ninth channel 26, a stator air duct 27 and a rotor air duct 28.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In this application, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The embodiment of the invention provides a permanent magnet motor, and referring to fig. 1, fig. 1 is a schematic structural diagram of the permanent magnet motor, the permanent magnet motor comprises a housing, a stator structure and a rotor structure, the stator structure and the rotor structure are located in the housing, the stator structure comprises a stator core 31 and a stator winding 32, the rotor structure comprises a rotating shaft 41 and a rotor core 42, and the rotating shaft 41 is installed in the housing through a bearing;

the permanent magnet machine further comprises: an external cooling air passage;

the external cooling air passage comprises an air inlet 13, a first cooling air passage, a second cooling air passage and a third cooling air passage;

the air inlet 13 is formed in the shell, the first ends of the first cooling air paths are communicated with the air inlet 13, and the second ends of the first cooling air paths penetrate through the inner wall of the shell and/or the stator core along the first direction;

the first end of the second cooling air path is communicated with the air inlet 13, and the second end of the second cooling air path passes through the second end of the rotating shaft 41 along the second direction and penetrates through the inner wall of the shell;

the first end of the third cooling air path is communicated with the second end of the at least one first cooling air path, and the second end passes through the first end of the rotating shaft 41 along the third direction and penetrates through the inner wall of the casing.

It should be noted that, because the rotating shaft 41 is mounted to the housing through the bearing, when the bearings mounted on two sides of the rotating shaft 41 generate heat, the heat can be radiated to the housing and/or the rotating shaft, and is communicated with the air inlet 13 through the first end of the first cooling air path, and the second end of the first cooling air path penetrates through the inner wall of the housing and/or the stator core along the first direction, so that the air entering through the air inlet 13 enters the first cooling air path, and cools the housing and the stator structure along the first direction, thereby performing a certain cooling function on the bearings; and first end and air intake 13 intercommunication through the second cooling wind path, the second end runs through the inner wall of casing along the second direction for the air that gets into from air intake 13 gets into the second cooling wind path, and cools off along the second direction to shells inner wall and rotor structure, and then has played certain cooling effect to the bearing.

Because first cooling wind path is many, consequently, first end through third cooling wind path and the second end intercommunication of first cooling wind path, the second end of third cooling wind path runs through the inner wall and the rotor structure of casing along the third direction, make the air that discharges from first cooling wind path get into the third cooling wind path, and cool down casing inner wall and rotor structure along the third direction, cool down the casing through above-mentioned first cooling wind path, second cooling wind path and third cooling wind path, and cooperate inside cooling wind path, can effectively cool down to the motor inside, and then avoid the casing cooling untimely, the temperature that leads to rotor structure and stator structure rises and leads to motor power to be restricted the problem to appear.

In this application, permanent-magnet machine adopts the duplex bearing, but the permanent-magnet machine heat dissipation problem of single bearing can also be solved to the technical scheme of this application.

Specifically, the housing includes: the device comprises a base, a first end cover 1 and a second end cover 2;

the first end cover 1 is positioned at the first end of the machine base, the second end cover 2 is positioned at the second end of the machine base, and the machine base, the first end cover 1 and the second end cover 2 form a space for installing a stator structure and a rotor structure;

the first cooling air path comprises a first channel 18 arranged on the base and a second channel 19 arranged on the first end cover 1, the first channel 18 and the second channel 19 are communicated with each other, and the first channel 18 extends along the axial direction;

the third cooling air path includes seventh, eighth, and ninth passages 24, 25, and 26 provided in first end cover 1, seventh, eighth, and ninth passages 24, 25, and 26 are communicated in this order, and seventh passage 24 extends in the radial direction.

It should be noted that, by providing the first channel 18 on the base, providing the second channel 19 on the first end cover 1, and arranging the first channel 18 and the second channel 19 to communicate with each other, and arranging the first channel 18 to extend in the axial direction, the air can pass through the first channel 18 and the second channel 19 in sequence after entering from the air inlet 13, and because the first channel 18 is an axially extending channel, the air can take away the heat on the base and the first end cover 1 when passing through the first channel 18, and finally is discharged through the second channel 19, while by arranging the seventh channel 24, the eighth channel 25 and the ninth channel 26 on the first end cover 1, and communicating the seventh channel 24, the eighth channel 25 and the ninth channel 26 in sequence, the air discharged from the second channel 19 can pass through the seventh channel 24, the eighth channel 25 and the ninth channel 26 in sequence, so that the air passes through the seventh channel 24, the eighth channel 25 and the ninth channel 26 in sequence, After the eighth channel 25 and the ninth channel 26, the heat is finally discharged through the ninth channel 26 and taken away from the first cover 1 and the rotating shaft 41.

Specifically, the eighth passage 25 communicates with the ninth passage 26 through the first ventilation gap 14, and the first ventilation gap 14 is a gap formed between the first end cover 1 and the rotor structure.

It should be noted that, the first ventilation gap 14 formed by the first end cover 1 and the rotor structure can meet the ventilation requirement, and then when air flows through the first ventilation gap 14, the heat at the position can be taken away, so as to cool the rotor structure.

Further, the seventh passage 24 is formed by the wind-guiding cover 5 provided on the first end cover 1.

It should be noted that, the air inducing cover 5 is arranged on the first end cover 1, so that the seventh channel 24 is formed between the air inducing cover 5 and the first end cover 1, and the air inducing cover 5 can be fixed on the first end cover 1 through the bolt connection, welding and riveting modes, so that the connection rigidity of the seventh channel 24 is effectively ensured, and the air is prevented from falling off to influence the air which cannot enter the first end cover 1 through the seventh channel 24 and the eighth channel 25 and is cooled.

Further, the second cooling air path includes a third channel 20, a fourth channel 21, a fifth channel 22, and a sixth channel 23 disposed on the second end cover 2, the third channel 20, the fourth channel 21, the fifth channel 22, and the sixth channel 23 are sequentially communicated, and the fourth channel 21, the fifth channel 22, and the sixth channel 23 all extend in the radial direction.

It should be noted that, by providing the third channel 20, the fourth channel 21, the fifth channel 22, and the sixth channel 23 on the second end cap 2 and communicating the third channel 20, the fourth channel 21, the fifth channel 22, and the sixth channel 23 in sequence, air can enter the air inlet 13 and can sequentially pass through the third channel 20, the fourth channel 21, the fifth channel 22, and the sixth channel 23, so that the air is finally discharged through the sixth channel 23 after passing through the third channel 20, the fourth channel 21, the fifth channel 22, and the sixth channel 23, and further takes away heat of the second end cap 2 and the rotating shaft 41.

Further, the fifth channel 22 communicates with the sixth channel 23 through a second ventilation gap 15, the second ventilation gap 15 being the gap formed by the second end cap 2 and the rotor structure.

It should be noted that the second ventilation gap 15 formed by the second end cover 2 and the rotor structure can meet the ventilation requirement, and then when air flows through the second ventilation gap 15, the heat in the second ventilation gap can be taken away, so that the rotor structure is cooled.

Further, the fourth channel 21 is formed by the wind cap 5 provided on the second end cap 2.

It should be noted that, set up induced air lid 5 on second end cap 2 for form fourth passageway 21 between induced air lid 5 and the second end cap 2, induced air lid 5 accessible bolted connection, welding, riveting mode are fixed in second end cap 2, and then effectively guarantee fourth passageway 21's connection rigidity, and can also avoid induced air lid 5 to drop and influence the air and can't get into second end cap 2 and to its cooling through fifth passageway 22.

Specifically, the air inlet 13 is provided in the base.

It should be noted that the air inlet 13 may be provided in the base, or may be provided in the second end cover 2 or the first end cover 1, and those skilled in the art can select the air inlet according to requirements, in this application, the air inlet 13 is preferably provided in the base, but the air inlet 13 is not limited to be provided in the base.

Further, permanent-magnet machine still includes: an internal cooling air passage and a fan 6;

the internal cooling air passage is located inside the housing, and passes through the stator core 31, the stator winding 32, and the rotor core 42 in a closed loop shape, and the air in the internal cooling air passage is driven and circulated by the fan 6.

It should be noted that, by providing the internal cooling air duct inside the housing, since the internal cooling air duct passes through the stator core 31, the stator winding 32 and the rotor core 42 in a closed ring shape, and the air in the internal cooling air duct is driven by the fan 6 to circulate, heat generated during the operation of the rotor structure and the stator winding 32 can be radiated to the air in the internal cooling air duct, and the radiated air can flow through the stator core 31 by the driving of the fan 6 after being heated, and radiate the heat to the housing, and the air in the external cooling air duct can cool the housing, so that the present application can cool the shaft and the housing, and further can prevent the motor power from being limited due to the over-high temperature in the rotor structure and the stator structure.

Further, the internal cooling air path includes a rotor air duct 28, a first cavity 16, a stator air duct 27 and a second cavity 17 which are sequentially communicated, wherein the first cavity 16 is defined by a first end of the stator core 31 and a first end of the rotor core 42 and an inner wall of the housing, the second cavity 17 is defined by a second end of the stator core 31 and a second end of the rotor core 42 and an inner wall of the housing, the rotor passage 28 axially penetrates through the rotor core 42, and the stator air duct 27 axially penetrates through the stator core 31.

It should be noted that a first cavity 16 is defined by the first end of the stator structure and the first end of the rotor structure and the inner wall of the housing, and a second cavity 17 is defined by the second end of the stator structure and the second end of the rotor structure and the inner wall of the housing, and the rotor air duct 28, the first cavity 16, the stator air duct 27 and the second cavity 17 which axially penetrate through the rotor structure are sequentially communicated, so that air can circularly flow in the rotor air duct 28, the first cavity 16, the stator air duct 27 and the second cavity 17 under the driving of the fan 6, the air further cools the rotor structure, when the air flows into the stator air duct 27, the heat energy of the air is radiated to the housing, and when the external cooling air path in the inner wall of the housing passes through the air, the housing air duct is cooled, so that the air in the stator 27 is cooled and flows into the rotor air duct 28 again after the temperature of the stator 27 is reduced, The first cavity 16 and the second cavity 27 cool the rotor structure again, thereby enhancing the cooling effect on the rotor structure.

Preferably, the air flow passage direction of the stator air duct 27 is opposite to the air flow direction in the first cooling air passage.

The first cooling air passage and the stator axial air passage 27 may be provided in opposite directions or in the same direction. However, since the air temperature in the stator axial air duct 27 can be significantly reduced by setting the air flow directions in the first cooling air path and the stator axial air duct 27 to be opposite to each other, it is preferable that the air flow directions in the first cooling air path and the stator axial air duct 27 are set to be opposite to each other in the present application.

The embodiment of the invention also provides a rail locomotive, which comprises a permanent magnet motor;

the permanent magnet motor comprises a shell, a stator structure and a rotor structure, wherein the stator structure and the rotor structure are positioned in the shell, the stator structure comprises a stator core 31 and a stator winding 32, the rotor structure comprises a rotating shaft 41 and a rotor core 42, and the rotating shaft 41 is arranged in the shell through a bearing;

the permanent magnet machine further comprises: an external cooling air passage;

the external cooling air passage comprises an air inlet 13, a second cooling air passage, a third cooling air passage and a first cooling air passage;

the first ends of the first cooling air paths are communicated with the air inlet 13, and the second ends of the first cooling air paths penetrate through the inner wall of the shell along the first direction;

the first end of the second cooling air path is communicated with the air inlet 13, and the second end of the second cooling air path passes through the second end of the rotating shaft 41 along the second direction and penetrates through the inner wall of the shell;

the first end of the third cooling air path is communicated with the second end of the at least one first cooling air path, and the second end passes through the first end of the rotating shaft 41 along the third direction and penetrates through the inner wall of the casing.

It should be noted that, because the rotating shaft 41 is mounted to the housing through the bearing, when the bearings mounted on two sides of the rotating shaft 41 generate heat, the heat can be radiated to the housing and/or the rotating shaft, and the first end of the first cooling air path is communicated with the air inlet 13, and the second end of the first cooling air path penetrates through the inner wall of the housing along the first direction, so that the air entering through the air inlet 13 enters the first cooling air path, and cools the inner wall of the housing along the first direction, thereby performing a certain cooling function on the bearing; and first end and air intake 13 intercommunication through the second cooling wind path, the second end runs through the inner wall of casing along the second direction for the air that gets into from air intake 13 gets into the second cooling wind path, and carries out cooling to shells inner wall along the second direction, and then has played certain cooling effect to the bearing.

Because first cooling wind path is many, consequently, first end through the third cooling wind path and the second end intercommunication of first cooling wind path, the second end of third cooling wind path runs through the inner wall of casing along the third direction, make the air that discharges from first cooling wind path get into the third cooling wind path, and cool down to the casing inner wall along the third direction, cool down the casing through above-mentioned first cooling wind path, second cooling wind path and third cooling wind path, and cooperate inside cooling wind path, can effectively cool down the inside of motor, and then avoid the casing cooling untimely, the temperature rise that leads to rotor structure and stator structure leads to motor power to be restricted the problem to appear.

To facilitate understanding of the above solution, the solution is further described below with reference to fig. 1.

A permanent magnet motor comprises a stator structure, a rotor structure, a front end cover (namely a first end cover 1), a rear end cover (namely a second end cover), a front bearing (namely a first bearing 7), a rear bearing (namely a second bearing 8), a fan (namely a fan 6), a front induced air cover (namely an induced air cover 5) and a rear induced air cover (namely an induced air cover 5), wherein the rotor structure is positioned on the inner side of the stator structure; the stator structure comprises a stator core 31 and a stator winding 32, wherein the stator core is provided with a through axial ventilation channel (namely a first channel 18 and a first channel 27), the rear part of the stator core is provided with a radial air inlet (namely an air inlet 13) for air inlet, and the stator winding is embedded in a stator core groove; the rotor structure comprises a rotor core 42 and a rotating shaft 41, the rotor core is provided with a through axial air duct (namely, a rotor air duct 28), and a fan is arranged on the front end face of the rotor core.

The rear end face of the front end cover is provided with a front end cover annular boss A (namely a first end cover annular boss 9) and a front end cover annular boss B (namely a second end cover annular boss 10), and the front end cover annular boss B is positioned on the inner side of the front end cover annular boss A; the annular boss A of the front end cover and the front end surface of the stator core are provided with contact seals; the front end cover annular boss B and the fan are provided with labyrinth seals; the front end cover is provided with a front end cover air passage A (namely a second passage 19), a front end cover air passage B (namely an eighth passage 25) and a front end cover air passage C (namely a ninth passage 26); a front ventilation gap (i.e., a first ventilation gap 14) is left between the front cover and the fan. The front induced draft cover is arranged on the front end cover and forms a front induced draft channel together with the front end cover air channel A and the front end cover air channel B.

The front end face of the rear end cover is provided with a rear end cover annular boss A (namely a third end cover annular boss 11) and a rear end cover annular boss B (namely a fourth end cover annular boss 12), and the rear end cover annular boss B is positioned on the inner side of the rear end cover annular boss A; the annular boss A of the rear end cover and the rear end face of the stator core are provided with contact seal; labyrinth seals are arranged on the annular boss B of the rear end cover and the rear end face of the rotor core; the rear end cover is provided with a rear end cover air duct A (namely a third channel 20), a rear end cover air duct B (namely a fifth channel 22) and a rear end cover air duct C (namely a sixth channel 23); and a rear ventilation gap (namely a second ventilation gap 15) is reserved between the rear end cover and the rear end face of the rotor core. The rear induced draft cover is arranged on the rear end cover and forms a rear induced draft channel together with the rear end cover air channel A and the rear end cover air channel B.

The radial air inlet, the stator axial air duct A and the front end cover air duct A form a first cooling air path; the rear air guide channel, the rear end ventilation gap and the rear end cover ventilation channel C jointly form a second cooling air path; the front air guide channel, the front end ventilation gap and the front end cover ventilation channel C form a third cooling air path together; the rotor axial air duct, the front end internal cavity, the stator axial air duct B and the rear end internal cavity form a fourth cooling air path (i.e., an internal cooling air path). The specific cooling process is as follows:

(1) and cooling air from an external fan enters a radial air inlet of the stator core, flows through the stator axial air duct A and is then discharged through the front end cover air duct A. In the process of flowing through the cooling air, the cooling air takes away heat generated by the stator iron core and the stator winding.

(2) Part of cooling air entering a radial air inlet of the stator core flows through the rear air guide channel and the rear ventilation gap and is discharged through the rear end cover ventilation channel C. In the process of flowing through by cooling air, the cooling air can take away the heat radiated to the rear end cover by the stator winding and the heat generated by the rotor and the rear bearing.

(3) Part of the cooling air flowing through the front end cover air duct A flows into the front ventilation gap through the front air guide duct and is discharged through the front end cover air duct C. In the process of flowing through by cooling air, the cooling air can take away the heat radiated to the front end cover by the stator winding and the heat generated by the rotor and the front bearing.

(4) The fan internal blades enable internal air to form circulating flow in the fourth cooling air path structure, part of heat generated by eddy current loss of the permanent magnet and radiating the stator winding to the rotor core is brought to the stator core, and the heat is taken away by external cooling air in the stator axial air duct A.

The invention has the following advantages:

1. the motor can perform directional ventilation cooling on the winding end part, the rotor, the bearing and other parts, reduce the temperature of the winding end part, the permanent magnet, the bearing and other parts, and improve the power density and the torque density of the motor.

2. The introduced cooling air does not change along with the rotating speed of the motor, and the traction motor is more suitable for the traction motor with complex rotating speed and load change.

In the application, the mounting mode of the induced draft cover on the end cover can be other connection modes such as bolt connection, welding, riveting and the like;

the air inducing cover can be arranged on the outer side, the inner side or both the inner side and the outer side of the end cover;

the air guide channel can be formed by installing an air guide cover on the end cover, or can be formed by casting the end cover (cast iron, cast steel and cast aluminum); the number of the air guide channels can be 1 or more; can be connected in series or in parallel.

The annular boss on the end cover can be formed by casting the end cover itself or by welding, bolting and other connection modes. The number of annular bosses can be more than 2.

The circumferential arrangement mode of the air passages on the end cover can be uniform or non-uniform, and the circumferential number can be odd or even. The number of air ducts may be more than 2. Viewed from an axial section, the two parts may be asymmetrical up and down.

The radial air inlet can be arranged on the stator, the front end cover or the rear end cover.

The air inducing cover can be an air duct wrapping part of the end covers, and can also be an air duct wrapping all the end covers in the circumferential direction.

The air of the cooled ventilation gap can be discharged from the rear end cover, and can also be partially or completely converged into the stator air duct for cooling.

The front induced draft cover can collect part or all of the air in the stator air duct into the front ventilation gap for cooling.

The solution can also be implemented on a motor with a single bearing structure.

The ventilation gap can be formed by the end cover and the rotor core directly or by installing a sealing piece in a transition mode.

Only the first, second and third cooling air path structures may be retained.

The fan blade generating the fourth air path structure circulating cooling air may be inside the fan, may be on the front end surface of the rotor core, or may be on the rear end surface of the rotor core.

The fan generating the fourth air path structure circulating cooling air may be provided at the front end of the rotor core or at the rear end of the rotor core.

The axial ventilation channels on the stator core can be uniformly or non-uniformly arranged in the circumferential direction, and the circumferential number can be odd or even. The number of air ducts arranged in parallel may be more than 2. Viewed from an axial section, the two parts may be asymmetrical up and down.

The axial ventilation channels on the rotor core can be uniformly or non-uniformly arranged in the circumferential direction, and the circumferential number can be odd or even. The number of air ducts arranged in parallel may be more than 2. Viewed from an axial section, the two parts may be asymmetrical up and down.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, the system or system embodiments are substantially similar to the method embodiments and therefore are described in a relatively simple manner, and reference may be made to some of the descriptions of the method embodiments for related points. The above-described system and system embodiments are merely illustrative, wherein units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.