A new energy vehicle permanent magnet synchronous motor

Abstract

The application discloses a new energy automobile permanent magnet synchronous motor, and relates to the technical field of new energy automobiles. The new energy automobile permanent magnet synchronous motor comprises a mounting shell, a stator is arranged in the mounting shell, and a rotor shaft is rotationally connected to the mounting shell in a penetrating mode; a cooling shell is detachably connected to the mounting shell, and the cooling shell is provided with circumferentially uniformly distributed cooling flow channels; a sealing cover is detachably connected to the mounting shell, the rotor shaft penetrates through the sealing cover and is rotationally connected to the sealing cover, the sealing cover is attached to the cooling shell, and a plurality of shunt plates in a linear array are arranged in the cooling flow channels. The application changes the positions of the shunt plates, changes the flow paths of the cooling liquid in the corresponding cooling flow channels, directly impacts the overheated positions of the mounting shell, and then performs targeted cooling on the overheated parts of the mounting shell, so that the stable working state of the internal parts of the mounting shell is ensured, and the normal use of the internal parts of the mounting shell is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new energy vehicles, and particularly relates to a permanent magnet synchronous motor for a new energy vehicle. BACKGROUND

[0002] The permanent magnet synchronous motor has become the preferred motor type of the current new energy vehicle driving system due to its excellent characteristics such as high power density, high torque density, high efficiency and wide speed regulation range. In order to meet the heat dissipation requirements of the vehicle under high load and long time operation, the modern vehicle permanent magnet synchronous motor generally adopts a liquid cooling heat dissipation mode, that is, a cooling flow channel is designed in the motor shell, and the heat generated in the motor is taken away through the circulation of the cooling liquid.

[0003] However, the water-cooled permanent magnet synchronous motor of the prior art under the actual working conditions of the new energy vehicle (such as continuous climbing, rapid acceleration, high-speed cruising, etc.) will cause uneven flow distribution, concentrated internal heat source distribution, contact thermal resistance or insufficient material thermal conductivity between the stator and the shell, and manufacturing process deviation due to the unreasonable design of the cooling flow channel of the motor shell, which will all cause the phenomenon of local overheating of the motor shell. The problem is specifically manifested as follows: when the motor is running, the shell temperature distribution is extremely uneven, and the temperature of some specific regions (the axial position of the permanent magnet) is significantly higher than that of other regions.

[0004] When the local overheating of the motor shell occurs, the irreversible demagnetization risk of the permanent magnet in the corresponding internal region will occur, causing permanent attenuation of the motor performance; it will also accelerate the aging of the winding insulation material, shorten the motor life, and even cause insulation breakdown failure; finally, the existence of the overheating point limits the peak and continuous output capacity of the whole motor to the temperature of the hottest point, which cannot fully exert the designed performance, and restricts the power performance and reliability of the new energy vehicle. SUMMARY

[0005] In order to overcome the shortcomings of the existing permanent magnet synchronous motor in use as proposed in the background art, the present application provides a permanent magnet synchronous motor for a new energy vehicle.

[0006] The technical scheme is as follows: A new energy vehicle permanent magnet synchronous motor, comprising: a mounting shell, a stator is mounted in the mounting shell, a rotor shaft is rotationally connected to the mounting shell in a penetrating manner, and a rotor is arranged on the rotor shaft and located in the mounting shell; a cooling shell is detachably connected to the mounting shell, a plurality of cooling flow channels are uniformly distributed on the cooling shell in a circumferential direction, and the cooling flow channels are used for flowing cooling liquid; a sealing cover is detachably connected to the mounting shell, the rotor shaft penetrates through the sealing cover and is rotationally connected to the sealing cover, the sealing cover is attached to the cooling shell, the sealing cover is provided with a water inlet flow channel and a water outlet flow channel for transmitting cooling liquid, a plurality of flow distribution plates are arranged in a linear array in the cooling flow channel, the plurality of flow distribution plates in the same cooling flow channel jointly divide the cooling flow channel into upper and lower flow channels that are in communication with each other, the water inlet flow channel is in communication with the upper flow channel, and the water outlet flow channel is in communication with the lower flow channel.

[0007] More preferably, a plurality of flow-through grooves are uniformly distributed on the mounting shell in a circumferential direction, the number of the flow-through grooves is consistent with the number of the cooling flow channels, a plurality of bimetallic strips are arranged in a linear array in the flow-through grooves, the number of the bimetallic strips is consistent with the number of the flow distribution plates, and the bimetallic strips and the flow distribution plates one-to-one correspond to each other, a connecting column is fixedly connected to one side of the flow distribution plate close to the corresponding bimetallic strip, the connecting column is in contact with the corresponding bimetallic strip, a return spring is fixedly connected to one side of the flow distribution plate away from the corresponding bimetallic strip, and the return spring is in contact with the cooling shell.

[0008] More preferably, the thermal expansion coefficient of the lower metal strip is smaller than that of the upper metal strip in the same temperature.

[0009] More preferably, a connecting frame is detachably connected in the cooling flow channel, and the connecting frame is used for limiting the corresponding flow distribution plate.

[0010] More preferably, a mounting frame is detachably connected in the flow-through groove, a plurality of limiting grooves are arranged on the mounting frame, and the bimetallic strip slides in the corresponding limiting groove to limit the corresponding bimetallic strip.

[0011] More preferably, the projections of the flow distribution plate, the bimetallic strip, the connecting frame and the mounting frame on the sealing cover are all fan-shaped, the angle of the fan-shaped projection of the connecting frame corresponding to the central angle is greater than the angle of the fan-shaped projection of the cooling flow channel corresponding to the central angle, and the angle of the fan-shaped projection of the mounting frame corresponding to the central angle is greater than the angle of the fan-shaped projection of the flow-through groove corresponding to the central angle.

[0012] More preferably, the sealing cover is provided with circumferentially uniformly distributed connecting holes, the circumferentially uniformly distributed connecting holes correspond to and communicate with the circumferentially uniformly distributed flow-through grooves one by one, the rotor shaft is fixed with a fan, the fan is used to accelerate the air flow speed in the flow-through groove, and the fan is located at one end of the rotor shaft close to the sealing cover.

[0013] More preferably, the side of the sealing cover away from the mounting shell is fixed with a cooling pipe through a support, and the cooling pipe communicates with the water inlet flow channel.

[0014] More preferably, the cooling pipe is located on the side of the fan away from the mounting shell.

[0015] More preferably, the cooling pipe is fixed with a plurality of heat dissipation fins, which are used to increase the heat dissipation area of the cooling pipe.

[0016] The beneficial effects of the present application are: by changing the position of the flow distribution plate, the flow path of the cooling liquid in the corresponding cooling flow channel is changed, the overheated position of the mounting shell is directly impacted, and the overheated part of the mounting shell is cooled in a targeted manner, the working state of the internal parts of the mounting shell is ensured to be stable, and the normal use of the internal parts of the mounting shell is ensured.

[0017] By driving the fan to rotate synchronously through the rotor shaft, the gas is guided to flow along the limiting groove and the flow-through groove, so that the flowing gas carries away the heat of the surface layer of the mounting shell, improves the heat dissipation speed of the mounting shell, forms a convection with the flow of the cooling liquid, improves the heat exchange efficiency of the cooling liquid and the mounting shell, further improves the uniformity of the temperature of the mounting shell, and ensures the normal use of the internal parts of the mounting shell. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a schematic diagram of the three-dimensional structure of the present application;

[0019] Figure 2 It is a schematic diagram of the three-dimensional structure of the fan and the cooling pipe of the present application;

[0020] Figure 3 It is a schematic diagram of the three-dimensional structure of the mounting shell of the present application;

[0021] Figure 4 It is a schematic diagram of the three-dimensional structure of the cooling shell of the present application;

[0022] Figure 5 It is a schematic diagram of the three-dimensional structure of the water inlet flow channel and the water outlet flow channel of the present application;

[0023] Figure 6 It is a schematic diagram of the three-dimensional structure of the reset spring and the connecting frame of the present application;

[0024] Figure 7This is a three-dimensional structural diagram of the diverter plate and bimetallic strip of the present invention;

[0025] Figure 8 This is a three-dimensional structural cross-sectional view of the mounting bracket of the present invention;

[0026] Figure 9 This is an exploded three-dimensional view of the bimetallic sheet and mounting bracket of the present invention;

[0027] Figure 10 This is a three-dimensional structural diagram of the connection hole and fan of the present invention;

[0028] Figure 11 This is a three-dimensional structural diagram of the cooling pipe and heat dissipation fins of the present invention.

[0029] The markings in the attached diagram are as follows: 1: Mounting housing, 2: Stator, 3: Rotor shaft, 4: Cooling housing, 5: Cooling channel, 6: Sealing cover, 7: Water inlet channel, 8: Drainage channel, 9: Diverter plate, 10: Flow groove, 11: Bimetallic strip, 12: Connecting column, 13: Return spring, 14: Connecting bracket, 15: Mounting bracket, 16: Limiting groove, 17: Connecting hole, 18: Fan, 19: Cooling pipe, 20: Heat dissipation fins. Detailed Implementation

[0030] The following description is only a preferred embodiment of the present invention and does not limit the scope of protection of the present invention. Example

[0031] This embodiment discloses a permanent magnet synchronous motor for new energy vehicles, which is an improvement on the existing liquid-cooled permanent magnet synchronous motor, enabling the permanent magnet synchronous motor to have the function of targeted heat dissipation of local parts of the motor housing.

[0032] like Figures 1-6 As shown, the permanent magnet synchronous motor includes: a mounting housing 1, a stator 2 installed inside the mounting housing 1, a rotor shaft 3 rotatably connected through the mounting housing 1, and a rotor located inside the mounting housing 1 mounted on the rotor shaft 3; a cooling housing 4 detachably connected to the mounting housing 1, the cooling housing 4 having circumferentially evenly distributed cooling channels 5 for supplying coolant flow; and a sealing cover 6 detachably connected to the mounting housing 1, the rotor shaft 3 passing through and rotatably connected to the sealing cover 6, the sealing cover 6 fitting against the cooling housing 4, the sealing cover 6 having an inlet channel 7 and a drain channel 8 for transmitting coolant, the cooling channel 5 having a plurality of linearly arranged diverter plates 9, the plurality of diverter plates 9 in the same cooling channel 5 dividing the cooling channel 5 into interconnected upper and lower channels, the inlet channel 7 communicating with the upper channel, and the drain channel 8 communicating with the lower channel.

[0033] In the above scheme, the stator 2, the rotor shaft 3 and the rotor on the rotor shaft 3 are all existing devices, and their specific mechanisms are not shown in detail in the figure, wherein the rotor on the rotor shaft 3 is inlaid with a plurality of permanent magnets; the cooling shell 4 is located outside the mounting shell 1; the specific number of the cooling flow channels 5 can be selected by the staff, and the cooling flow channels 5 are used to guide the flow of the cooling liquid; the sealing cover 6 is located on the left side of the mounting shell 1, and is used to seal the cooling flow channels 5 together with the mounting shell 1; the water inlet flow channel 7 and the water outlet flow channel 8 are both annular, the diameter of the circle where the water outlet flow channel 8 is located is smaller than the diameter of the circle where the water inlet flow channel 7 is located, and in this embodiment, the water inlet flow channel 7 is in communication with the outlet end of the automobile cooling device, and the water outlet flow channel 8 is in communication with the inlet end of the automobile cooling device; the number of the flow dividing plates 9 in the same cooling flow channel 5 can be selected by the staff, and four are taken as an example in the figure and in the text, the liquid in the cooling flow channel 5 flows from the upper flow channel to the right, flows from the upper flow channel to the lower flow channel, and then flows to the left along the lower flow channel, and the whole is in the shape of "U"; during the assembly of the permanent magnet synchronous motor, the staff can add rubber gaskets between the mounting shell 1 and the cooling shell 4, between the cooling shell 4 and the sealing cover 6, and at the connection between the mounting shell 1 and the sealing cover 6, so as to improve the sealing performance of the above-mentioned connections.

[0034] As shown in Figures 3-7 , the mounting shell 1 is provided with circumferentially uniformly distributed flow-through grooves 10, the specific number of the flow-through grooves 10 is consistent with the number of the cooling flow channels 5, a plurality of bimetallic strips 11 in a straight line array are arranged in the flow-through grooves 10, the number of the bimetallic strips 11 is consistent with the number of the flow dividing plates 9, and they one-to-one correspond, a connecting column 12 is fixedly connected to the side of the flow dividing plate 9 close to the corresponding bimetallic strip 11, the connecting column 12 is in contact with the corresponding bimetallic strip 11, a return spring 13 is fixedly connected to the side of the flow dividing plate 9 away from the corresponding bimetallic strip 11, the return spring 13 is in contact with the cooling shell 4, and the thermal expansion coefficient of the lower metal strip is smaller than that of the upper metal strip under the same temperature.

[0035] In the above scheme, the flow channel 10 is used to increase the contact area between the outer side of the mounting shell 1 and the air, thereby accelerating the heat dissipation efficiency of the mounting shell 1; the bimetallic strip 11 is the existing device, which is composed of two metal sheets of different materials, and during the heating process of the bimetallic strip 11, the metal sheet far away from the rotor shaft 3 is first heated and expanded, so that the middle part of the bimetallic strip 11 protrudes away from the rotor shaft 3 (the short side of the bimetallic strip 11 bends, and the long side does not change), in normal state, the bimetallic strip 11 is attached to the side of the corresponding flow channel 10 close to the rotor shaft 3; the specific number of connecting columns 12 on the same shunt plate 9 can be selected by the staff, and two are taken as an example in the figure and in the text; the specific number of return springs 13 on the same shunt plate 9 can also be selected by the staff, and one is taken as an example in the figure and in the text, and the return spring 13 is always in a compressed state; the projection of the cooling flow channel 5 and the flow channel 10 on the sealing cover 6 is arc-shaped, and the area of the projection of the flow channel 10 on the sealing cover 6 is smaller than that of the cooling flow channel 5 on the sealing cover 6, which is used to increase the contact area between the cooling flow channel 5 and the mounting shell 1, and to ensure that the cooling liquid can normally cool the mounting shell 1.

[0036] Further, as shown in Figures 6-9 , the cooling flow channel 5 is detachably connected with a connecting frame 14, the connecting frame 14 is used to limit the corresponding shunt plate 9, and the flow channel 10 is detachably connected with a mounting frame 15, the mounting frame 15 is provided with a plurality of limiting grooves 16, and the bimetallic strip 11 is located in the corresponding limiting groove 16 and slides, thereby limiting the corresponding bimetallic strip 11.

[0037] In the above scheme, the connecting frame 14 is used to improve the stability of the axial position of the shunt plate 9 thereon, and to reduce the influence of the vibration of the vehicle on the position of the shunt plate 9 during driving; the mounting frame 15 is used to improve the stability of the axial position of the bimetallic strip 11 thereon, and to reduce the influence of the vibration of the vehicle on the position of the bimetallic strip 11 during driving, and at the same time, the left and right sides of the bimetallic strip 11 slide along the corresponding limiting grooves 16 during the protrusion of the middle part of the bimetallic strip 11.

[0038] Further, as shown in Figure 6 and Figure 7As shown, the projections of the flow distribution plate 9, the bimetallic strip 11, the connecting frame 14 and the mounting frame 15 on the sealing cover 6 are all fan-shaped, and the angle of the fan-shaped projection of the connecting frame 14 corresponding to the central angle of a circle is greater than the angle of the fan-shaped projection of the cooling flow channel 5 corresponding to the central angle of a circle, so that the connecting frame 14 can form a spliced structure with the cooling shell 4 during installation, improving the stability of the connection between the two and the sealing property therebetween. The angle of the fan-shaped projection of the mounting frame 15 corresponding to the central angle of a circle is greater than the angle of the fan-shaped projection of the flow passage 10 corresponding to the central angle of a circle, so that the mounting frame 15 can form a spliced structure with the mounting shell 1 during installation, improving the stability of the connection between the two.

[0039] The specific working process of the above scheme is as follows:

[0040] First, the staff installs the permanent magnet synchronous motor (hereinafter referred to as motor) in the designated position of the new energy vehicle, then connects the water inlet channel 7 with the outlet end of the vehicle cooling device, connects the water outlet channel 8 with the inlet end of the vehicle cooling device, and connects the rotor shaft 3 with the vehicle power device through a transmission device. After the above installation is completed, the motor can be put into use.

[0041] When the motor is working, the rotor shaft 3 drives the rotor on it to rotate synchronously, cuts the magnetic induction lines and generates corresponding heat in the process. In this process, the vehicle cooling device delivers cooling liquid into the water inlet channel 7. The cooling liquid entering the water inlet channel 7 flows along the path of water inlet channel 7→upper flow channel of cooling flow channel 5 (flowing to the right)→lower flow channel of cooling flow channel 5 (flowing to the left)→water outlet channel 8→vehicle cooling device, and absorbs the heat generated in the working process of the motor in the process of flowing, maintaining the stability of the overall temperature of the motor in the working process and ensuring that the motor can work normally.

[0042] During the working process of the motor, when a part of the motor overheats, the following describes the right side of the upper side of the motor as an example:

[0043] When the right part of the upper side of the motor overheats, the temperature of the right part of the upper side of the mounting shell 1 is higher than that of the remaining positions, and the temperature of the bimetallic strip 11 (the rightmost bimetallic strip 11) of the mounting shell 1 is also synchronously increased. When the temperature of the upper metal strip in the bimetallic strip 11 reaches a threshold value (the value is related to the material of the bimetallic strip 11), the bimetallic strip 11 deforms, the middle part protrudes upward, and the bimetallic strip 11 pushes the corresponding two connecting columns 12 to move upward synchronously, and the corresponding reset spring 13 is compressed and stored in the process, and at the same time, the height difference between the rightmost shunt plate 9 and the adjacent shunt plate 9 is generated, thereby generating a gap between the two shunt plates 9, thereby changing the original flow path of the cooling liquid in the cooling flow channel 5, and the part of the cooling liquid flowing downward after flowing through the third shunt plate 9 (from left to right), thereby directly impacting the overheated position of the mounting shell 1, thereby targetedly cooling the overheated part of the mounting shell 1, ensuring the stable working state of the internal part of the mounting shell 1, and ensuring the normal use of the internal part of the mounting shell 1, and the control terminal of the automobile sends a warning in the cab to remind the driver that the motor is locally overheated.

[0044] After the overheated part of the mounting shell 1 is cooled down,

[0045] If the temperature of the part decreases to the normal temperature, the temperature transmitted to the bimetallic strip 11 of the mounting shell 1 also decreases synchronously, thereby gradually resetting the bimetallic strip 11 to the undeformed state. In the resetting process of the bimetallic strip 11, the supporting force of the bimetallic strip 11 on the corresponding connecting column 12 also gradually decreases, thereby moving the corresponding two connecting columns 12 downward synchronously under the action of the corresponding reset spring 13. When the bimetallic strip 11 is reset, the corresponding shunt plate 9 is reset synchronously, and the flow path in the cooling flow channel 5 is again separated into two flow channels.

[0046] If the temperature of the part does not decrease significantly, the driver needs to stop the vehicle in time to check the motor to ensure driving safety. Embodiment

[0047] On the basis of embodiment 1, the embodiment continues to optimize and improve a new energy vehicle permanent magnet synchronous motor, and further improves the heat dissipation capacity.

[0048] Further, as Figure 2 , Figure 10 and Figure 11As shown, the sealing cover 6 is provided with a plurality of circumferentially uniformly distributed connecting holes 17, which are in one-to-one correspondence with and in communication with the circumferentially uniformly distributed flow-through grooves 10. The rotor shaft 3 is fixedly connected with a fan 18, which is used to accelerate the air flow speed in the flow-through grooves 10. The fan 18 is located at one end of the rotor shaft 3 close to the sealing cover 6.

[0049] In the above scheme, the fan 18 is located at the left end of the rotor shaft 3, and the fan 18 is located in the sealing cover 6. During the rotation of the rotor shaft 3, the rotor shaft 3 drives the fan 18 to rotate synchronously, guiding the gas to flow from left to right. In this process, the gas flows rightward along the connecting holes 17 and the flow-through grooves 10, so that the flowing gas carries away the heat on the surface of the mounting shell 1, improves the dissipation speed of the heat on the mounting shell 1, and forms a convection with the flow of the cooling liquid. The flowing gas cools and heats the cooling liquid after heat exchange, improves the heat exchange efficiency of the cooling liquid and the mounting shell 1, further improves the uniformity of the temperature of the mounting shell 1, and ensures the normal use of the parts in the mounting shell 1. Embodiment

[0050] Based on Embodiment 2, this embodiment further optimizes and improves the permanent magnet synchronous motor for new energy vehicles.

[0051] Further, as shown in Figure 2 , Figure 10 and Figure 11 , the sealing cover 6 is fixedly connected with a cooling pipe 19 through a support away from the mounting shell 1. The cooling pipe 19 is in communication with the water inlet channel 7.

[0052] In the above scheme, the cooling pipe 19 is spiral-shaped, which is used to increase the contact area of the cooling liquid and the cooling pipe 19, and improve the heat dissipation efficiency of the external air.

[0053] Further, as shown in Figure 10 and Figure 11 , the cooling pipe 19 is located away from the mounting shell 1 on the side of the fan 18, so that the gas first contacts the cooling pipe 19 and then flows along the connecting holes 17.

[0054] Further, as shown in Figure 10 and Figure 11 , the cooling pipe 19 is fixedly connected with a plurality of heat dissipation fins 20, which are used to increase the heat dissipation area of the cooling pipe 19.

[0055] The specific working process of the above scheme is as follows:

[0056] In the use of the motor, the worker needs to connect the cooling pipe 19 with the water inlet channel 7, so that the cooling liquid flowing into the water inlet channel 7 is divided into the part flowing into the cooling pipe 19, and the part flows along the cooling pipe 19, so that the part exchanges heat with the outside through the side wall of the cooling pipe 19 and all the heat dissipation fins 20, and the temperature of the air around the motor is reduced.

[0057] And in the rotation of the fan 18, the airflow flowing under the influence of the fan 18 first contacts the cooling pipe 19, so that the heat exchange efficiency of the cooling liquid and the airflow is improved, the temperature of the airflow before entering the connecting hole 17 is further reduced, the heat exchange effect of the airflow with the installation shell 1 is improved, and the stability of the heat dissipation efficiency is ensured.

[0058] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited to this, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A permanent magnet synchronous motor for new energy vehicles, characterized in that, include: Mounting housing (1), stator (2) is installed inside the mounting housing (1), and rotor shaft (3) is rotatably connected through the mounting housing (1). Rotor shaft (3) is provided on the rotor shaft (3) and located inside the mounting housing (1). Cooling shell (4) is detachably connected to mounting shell (1). Cooling channels (5) are provided on the cooling shell (4) and are evenly distributed in the circumference. The cooling channels (5) are used to supply coolant flow. A sealing cover (6) is detachably connected to the mounting shell (1). The rotor shaft (3) passes through the sealing cover (6) and is rotatably connected to it. The sealing cover (6) is in contact with the cooling shell (4). The sealing cover (6) is provided with an inlet channel (7) and a drain channel (8) for transmitting coolant. A number of diverter plates (9) in a linear array are provided in the cooling channel (5). The number of diverter plates (9) in the same cooling channel (5) together divide the cooling channel (5) into interconnected upper and lower channels. The inlet channel (7) is connected to the upper channel, and the drain channel (8) is connected to the lower channel. The mounting shell (1) is provided with circumferentially evenly distributed flow grooves (10). The specific number of the flow grooves (10) is the same as the number of the cooling channels (5). A number of bimetallic strips (11) in a linear array are provided in the flow grooves (10). The number of bimetallic strips (11) is the same as the number of the diverter plates (9), and the two correspond one to one. A connecting post (12) is fixedly connected to the side of the diverter plate (9) close to the corresponding bimetallic strip (11). The connecting post (12) contacts the corresponding bimetallic strip (11). A return spring (13) is fixedly connected to the side of the diverter plate (9) away from the corresponding bimetallic strip (11). The return spring (13) contacts the cooling shell (4). At the same temperature, the coefficient of thermal expansion of the lower metal sheet in the bimetallic strip (11) is smaller than that of the upper metal sheet.

2. The permanent magnet synchronous motor for new energy vehicles according to claim 1, characterized in that, A connecting frame (14) is detachably connected inside the cooling channel (5), and the connecting frame (14) is used to limit the corresponding flow divider (9).

3. A permanent magnet synchronous motor for new energy vehicles according to claim 2, characterized in that, The circulation groove (10) is detachably connected to a mounting bracket (15), and the mounting bracket (15) is provided with a plurality of limiting grooves (16). The bimetallic strip (11) slides in the corresponding limiting groove (16) to limit the corresponding bimetallic strip (11).

4. A permanent magnet synchronous motor for new energy vehicles according to claim 3, characterized in that, The projections of the flow divider (9), the bimetallic strip (11), the connecting bracket (14), and the mounting bracket (15) onto the sealing cover (6) are all fan-shaped. The angle of the central angle corresponding to the fan-shaped projection of the connecting bracket (14) is greater than the angle of the central angle corresponding to the fan-shaped projection of the cooling channel (5). The angle of the central angle corresponding to the projection of the mounting bracket (15) is greater than the angle of the central angle corresponding to the projection of the flow groove (10).

5. A permanent magnet synchronous motor for new energy vehicles according to claim 4, characterized in that, The sealing cover (6) is provided with circumferentially evenly distributed connecting holes (17). The circumferentially evenly distributed connecting holes (17) correspond one-to-one with the circumferentially evenly distributed flow grooves (10) and are interconnected. A fan (18) is fixedly connected to the rotor shaft (3). The fan (18) is used to accelerate the airflow speed in the flow groove (10). The fan (18) is located at one end of the rotor shaft (3) near the sealing cover (6).

6. A permanent magnet synchronous motor for new energy vehicles according to claim 5, characterized in that, The sealing cover (6) is fixed to a cooling pipe (19) by a bracket on the side away from the mounting shell (1), and the cooling pipe (19) is connected to the water inlet channel (7).

7. A permanent magnet synchronous motor for new energy vehicles according to claim 6, characterized in that, The cooling pipe (19) is located on the side of the fan (18) away from the mounting housing (1).

8. A permanent magnet synchronous motor for new energy vehicles according to claim 7, characterized in that, Several heat dissipation fins (20) are fixed to the cooling pipe (19) to increase the heat dissipation area of ​​the cooling pipe (19).

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