Motor and Method for Testing Motor Cooling Effect

Abstract

The present invention relates to the technical field of motor heat dissipation, and discloses a motor and a method for testing the cooling effect of the motor, wherein the motor includes a stator and a rotor and a cooling pipe, the cooling pipe includes an inlet, an outlet and a Tesla valve structure, the Tesla valve structure includes a main channel and a branch channel, the front end of the main channel in the radial direction is connected to the outlet, and the rear end of the main channel in the radial direction is connected to the inlet; the two ends of the branch channel are respectively connected to the main channel, and the inner side wall of the branch channel near the outlet forms an angle with the radial direction of the main channel. In the technical solution of the present invention, the main channel and the branch channel are separated, and part of the coolant enters the branch channel after the separation; the coolant in the branch channel merges with the coolant in the main channel to generate spin and turbulence in the main channel, destroying the stability of the coolant flow; the coolant can extend the time of heat exchange with the stator and rotor after the flow stability is destroyed, thereby achieving a better heat dissipation effect.

Description

Technical Field

[0001] The present invention relates to the technical field of motor heat dissipation, and in particular to a motor and a method for testing the cooling effect of the motor. Background Art

[0002] With the development of motors, people have higher and higher requirements for motors. The power density of motors is a key factor affecting motor performance, so the power density of motors is getting higher and higher. A higher power density means a greater amount of heat generated inside the motor, which makes the overall temperature of the motor higher when it is working, and the windings and permanent magnets in the motor will fail due to excessive temperature.

[0003] Therefore, the motor needs to be cooled simultaneously. There are five ways to cool the motor: natural cooling, forced air cooling, liquid cooling, oil cooling and combined cooling. In order to achieve a stable heat dissipation effect, liquid cooling is generally used for motors.

[0004] At present, a spiral flow channel structure or an axial flow channel structure is usually designed on the motor housing of an electric vehicle, and the motor is cooled by heat exchange by flowing coolant through the spiral flow channel structure or the axial flow channel structure, but the structural characteristics of the two make their heat dissipation effect poor. Summary of the invention

[0005] The main purpose of the present invention is to provide a motor, aiming to improve the heat dissipation effect of the motor.

[0006] To achieve the above object, the present invention provides a motor, the motor includes a stator and a rotor and a cooling pipe, the cooling pipe is spirally wound around the outer wall of the stator and the rotor, the cooling pipe includes an inlet, an outlet and a Tesla valve structure, and the Tesla valve structure includes:

[0007] a main flow channel, wherein one end of the main flow channel closer to the front in the radial direction is connected to the outlet, and one end of the main flow channel closer to the rear in the radial direction is connected to the inlet; and

[0008] The branch channel has two ends connected to the main channel respectively, and the inner side wall of the front end of the branch channel in the radial direction close to the outlet forms an angle with the radial direction of the main channel.

[0009] Optionally, the angle between the inner side wall of the branch channel close to the outlet and the radial direction is A, and 60°≤A≤90°.

[0010] Optionally, the width of the main channel gradually decreases along the radial direction.

[0011] Optionally, the Tesla valve structure includes two branch channels, and the two branch channels are respectively located on both sides of the main channel.

[0012] Optionally, the two branch channels are arranged with a dislocation in the radial direction.

[0013] Optionally, the cooling pipeline includes a plurality of the Tesla valve structures, and the Tesla valve structures are connected end to end.

[0014] Optionally, the cooling pipeline further includes a plurality of straight channels, and adjacent two Tesla valve structures are communicated through one straight channel.

[0015] Optionally, the side wall of the straight channel is arranged flat in the radial direction.

[0016] Optionally, the connection line between the inlet and the outlet is parallel to the straight line extending along the direction of the rotation axis of the stator and rotor.

[0017] The present invention also provides a method for testing the cooling effect of a motor. The method for testing the cooling effect of the motor is applied to the above-mentioned motor; the number of Tesla valve structures in the cooling pipeline and the width of the straight channel extending along the radial direction of the main channel are adjusted, and the heat dissipation simulation test is carried out on the adjusted motor, and the cooling effect of the motor is generated according to the test result.

[0018] In the technical solution of the present invention, the motor includes a stator and rotor and a cooling pipeline. The cooling pipeline is spirally wound around the outer wall of the stator and rotor. The cooling pipeline includes an inlet, an outlet and a Tesla valve structure; the Tesla valve structure includes a main channel and a branch channel. One end of the main channel closer to the radial direction communicates with the outlet, and the end of the main channel closer to the radial direction communicates with the inlet; both ends of the branch channel communicate with the main channel respectively, and the inner side wall closer to the outlet at one end of the branch channel in the radial direction forms an angle with the radial direction of the main channel. The coolant enters the cooling pipeline from the inlet and flows out of the cooling pipeline from the outlet; and the cooling pipeline is wound around the outer wall of the stator and rotor, and the coolant can exchange heat with the stator and rotor when flowing in the cooling pipeline to reduce the temperature of the stator and rotor. In the technical solution of the present invention, the coolant flows into the cooling pipeline and enters the main channel. After being split, part of the coolant enters the branch channel; the coolant in the main channel flows along the radial direction of the main channel, and the inner side wall of the branch channel close to the outlet forms an angle with the radial direction. Therefore, when the coolant in the branch channel flows back into the main channel, the flow direction will form an angle with the flow direction of the coolant in the main channel. In this way, after the coolant converges, it will generate self-rotation and turbulence in the cooling pipeline, which destroys the stability of the coolant flow; after the flow stability of the coolant is destroyed, the time for heat exchange with the stator and rotor can be extended, so that a better heat dissipation effect can be achieved. Description of the Drawings

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0020] Figure 1 An exploded view of an embodiment of the motor provided by the present invention;

[0021] Figure 2 A three-dimensional structural schematic diagram of the cooling pipeline in the motor;

[0022] Figure 3 A planar structural schematic diagram of an embodiment of the Tesla valve structure in the motor;

[0023] Figure 4 A planar structural schematic diagram of another embodiment of the Tesla valve structure in the motor;

[0024] Figure 5 An effect schematic diagram of a simulation test of the motor;

[0025] Figure 6 Another effect schematic diagram of the simulation test of the motor;

[0026] Figure 7 Another effect schematic diagram of the simulation test of the motor.

[0027] Explanation of the reference numerals in the drawings:

[0028] Label Name Label Name 1000 Motor 212 Branch channel 1 Stator and rotor 2a Inlet 2 Cooling pipe 2b Outlet 21 Tesla valve structure 22 DC channel 211 Main channel

[0029] The realization of the purpose, functional features and advantages of the present invention will be further described with reference to the embodiments and the drawings. Detailed implementation manners

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0031] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0032] In addition, the descriptions involving "first", "second", etc. in the present invention are for descriptive purposes only, and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel scenarios. Taking "A and / or B" as an example, it includes scenario A, or scenario B, or the scenario where both A and B are satisfied simultaneously. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0033] Please refer to Figure 1 、 Figure 2 、 Figure 3 and Figure 4 , to solve the problem of poor heat dissipation effect of the motor 1000, the present invention proposes a motor 1000, including:

[0034] A stator-rotor 1 and a cooling pipe 2, the cooling pipe 2 is spirally wound around the outer wall of the stator-rotor 1, the cooling pipe 2 includes an inlet 2a, an outlet 2b and a Tesla valve structure 21; the Tesla valve structure 21 includes a main flow channel 211 and a branch flow channel 212, one end of the main flow channel 211 closer to the radial direction communicates with the outlet 2b, and one end of the main flow channel 211 farther from the radial direction communicates with the inlet 2a; both ends of the branch flow channel 212 communicate with the main flow channel 211 respectively, and the inner side wall closer to the outlet 2b at one end of the branch flow channel 212 along the radial direction forms an angle with the radial direction of the main flow channel 211. The coolant enters the cooling pipe 2 from the inlet 2a and flows out of the cooling pipe 2 from the outlet 2b; and the cooling pipe 2 is wound around the outer wall of the stator-rotor 1, and the coolant can exchange heat with the stator-rotor 1 when flowing in the cooling pipe 2 to reduce the temperature of the stator-rotor 1.

[0035] In the technical solution of the present invention, the coolant flows into the cooling pipe 2 and enters the main flow channel 211, and after being split, part of the coolant enters the branch flow channel 212; the coolant in the main flow channel 211 flows along the radial direction of the main flow channel 211, and the inner side wall of the branch flow channel 212 close to the outlet 2b forms an angle with the radial direction. Therefore, when the coolant in the branch flow channel 212 flows back into the main flow channel 211, the flow direction will form an angle with the flow direction of the coolant in the main flow channel 211. In this way, after the coolant converges, it will generate self-rotation and turbulence in the cooling pipe 2, and the stability of the coolant flow is destroyed; after the flow stability of the coolant is destroyed, the heat exchange time with the stator-rotor 1 can be extended, and thus a better heat dissipation effect can be achieved. At the same time, due to the reduction in flow velocity, the intensity of the collision of the coolant in the cooling flow channel is reduced, so the noise generated by the collision of the coolant with the cooling pipe 2 is smaller.

[0036] Specifically, the angle between the inner wall of the branch channel 212 near the outlet 2b and the radial direction is A, where 60° ≤ A ≤ 90°. In one embodiment, A is 75°. When the angle of A is too small, the spin and turbulence effects generated after the coolant in the branch channel 212 converges with the coolant in the main channel 211 are not good, and the effect of reducing the flow rate is not obvious, resulting in poor cooling effect of the motor 1000; when the angle of A is too large, the coolant in the branch channel 212 will flow back, reducing the flow rate of the coolant in the branch channel 212. The reduced flow rate of the coolant in the branch channel 212 will cause the spin and turbulence effects to be not good after the coolant in the branch channel 212 converges with the coolant in the main channel 211, resulting in poor cooling effect of the motor 1000. Therefore, it is preferred that A is 75°.

[0037] In one embodiment, the width of the main channel 211 gradually decreases in the radial direction, so that when the coolant enters the cooling pipe 2 from the inlet 2a, more coolant can enter the branch channel 212, thereby making the spin and turbulence effects generated when the coolant in the branch channel 212 flows into the main channel 211 better, and thus improving the cooling effect of the motor 1000.

[0038] It can be understood that the Tesla valve structure 21 includes at least one branch channel 212. In one embodiment, the Tesla valve includes two branch channels 212, and the two branch channels 212 are respectively located on both sides of the main channel 211. Such a setting makes the coolant on both sides of the main channel 211 be disturbed by the coolant in the branch channel 212 to generate spin and turbulence, avoiding the situation that the coolant on the side of the main channel 211 farther from the liquid outlet of the branch channel 212 is less disturbed by the coolant in the branch channel 212 when the branch channel 212 is arranged on one side of the main channel 211. In this way, the spin and turbulence effects generated when the coolant in the branch channel 212 flows into the main channel 211 are improved, and thus the cooling effect of the motor 1000 is improved.

[0039] Specifically, the two branch channels 212 are arranged in a staggered manner in the radial direction, avoiding the liquid outlets of the two branch channels 212 being arranged opposite to the main channel 211. Therefore, the impact between the coolants flowing out of the liquid outlets of the two branch channels 212 is reduced, which affects the spin and turbulence of the coolant, and further improves the cooling effect of the motor 1000.

[0040] It can be understood that the cooling pipe 2 includes a plurality of Tesla valve structures 21. In one embodiment, the cooling pipe 2 includes twenty Tesla valve structures 21, and the twenty Tesla valve structures 21 are connected end to end. Such a setting enhances the spin and turbulence effects of the coolant, further improving the cooling effect of the motor 1000.

[0041] Further, the cooling pipe 2 further includes a plurality of straight channels 22. In one embodiment, the cooling pipe 2 further includes nineteen straight channels 22, and two adjacent Tesla valve structures 21 are connected through a straight channel 22. Specifically, the side wall of the straight channel 22 is straight along the radial direction, and this setting is to ensure that the liquid flow direction of the coolant entering the main channel 211 from the straight channel 22 is along the radial direction.

[0042] In one embodiment, the connection line between the inlet 2a and the outlet 2b is parallel to the straight line extending along the rotation axis direction of the stator-rotor 1. Such a setting makes the inlet 2a and the outlet 2b located on the same side of the stator-rotor 1, which can shorten the layout length of the external coolant path and reduce the layout cost of the external coolant path.

[0043] The present invention also proposes a method for testing the cooling effect of a motor. The method for testing the cooling effect of a motor is applied to the above-mentioned motor 1000. The specific structure of the motor 1000 refers to the above embodiments. Since the method for testing the cooling effect of this motor adopts all the technical solutions of the above-mentioned all embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, and will not be elaborated here one by one.

[0044] Adjust the number of Tesla valve structures 21 in the cooling pipe 2 and the width of the straight channel 22 extending along the radial direction of the main channel 211, and conduct a heat dissipation simulation test on the adjusted motor 1000, and generate the cooling effect of the motor 1000 according to the test results.

[0045] Please refer to Figure 5 , define the width of the straight channel 22 extending along the radial direction as L, and take L as 10mm, 30mm, 50mm, 70mm, 90mm respectively to conduct a heat dissipation simulation test on the motor 1000, and generate the cooling effect of the motor 1000 according to the test results. It can be obtained from the figure that the heat dissipation effect of the motor 1000 is the best when L is 30mm.

[0046] Please refer to Figure 6 , take the number of Tesla valve structures 21 in the cooling pipe 2 as 15, 30, 45, 60, 75 respectively to conduct a heat dissipation simulation test on the motor 1000, and generate the cooling effect of the motor 1000 according to the test results. It can be obtained from the figure that the heat dissipation effect of the motor 1000 is the best when the number of Tesla valve structures 21 in the cooling pipe 2 is 75.

[0047] Through single-factor analysis, it can be known that different spacings and numbers of stages will affect the heat dissipation performance of the motor 1000. There is a balance point for the evaluation index of design parameters within a certain range. In order to verify the influence of the spacing and number of stages of the Tesla valve type cooling channel on the cooling effect and energy consumption of the motor 1000, two parameters, namely the width of the straight channel 22 extending along the radial direction and the number of Tesla valve structures 21 in the cooling pipe 2, are taken as the optimization objectives. Please refer toFigure 7 , the widths L of the straight channels 22 extending in the radial direction are respectively taken as 10 mm, 30 mm, 50 mm, 70 mm, 90 mm, and the maximum numbers of the Tesla valve structures 21 in the cooling pipes 2 corresponding to the respective widths of the straight channels 22 are 60, 40, 30, 25, 20. Twenty-five groups of data are obtained by combining them one by one for simulation analysis. A represents the 25 groups of simulation data, and the simulation results are as Figure 7 shown. It is analyzed that when the number of the Tesla valve structures 21 in the cooling pipes 2 increases, the heat dissipation effect is better but the pressure drop also increases. The increase in the pressure drop means greater energy loss of the motor 1000. Therefore, in order to balance better heat dissipation effect and lower energy loss, it is preferred that the width L of the straight channel 22 extending in the radial direction is 90 mm, and the number of the Tesla valve structures 21 in the cooling pipe 2 is 16. In this way, the motor 1000 can achieve better cooling effect while having smaller energy loss.

[0048] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural transformation made by using the content of the specification and drawings of the present invention under the inventive concept of the present invention, or direct / indirect application in other related technical fields is included in the patent protection scope of the present invention.

Claims

1. A motor (1000), comprising a stator and rotor (1) and a cooling pipe (2), wherein the cooling pipe (2) is spirally wound around the outer wall of the stator and rotor (1), and the cooling pipe (2) comprises an inlet (2a), an outlet (2b) and a Tesla valve structure (21), characterized in that: The Tesla valve structure (21) comprises: a main flow channel (211), wherein a front end of the main flow channel (211) in the radial direction is connected to the outlet (2b), and a rear end of the main flow channel (211) in the radial direction is connected to the inlet (2a); and A branch channel (212), wherein both ends of the branch channel (212) are respectively connected to the main channel (211), and an inner side wall of the branch channel (212) close to the outlet (2b) forms an angle with the radial direction; The included angle between the inner side wall of the branch channel (212) close to the outlet (2b) and the radial direction is A, 60°≤A≤90°; The width of the main channel (211) gradually decreases along the radial direction; The Tesla valve structure (21) comprises two branch channels (212), and the two branch channels (212) are respectively located on both sides of the main channel (211); The two branch flow channels (212) are staggered in the radial direction; The cooling pipeline (2) further comprises a plurality of straight flow channels (22), and two adjacent Tesla valve structures (21) are connected via a straight flow channel (22); The side wall of the direct current channel (22) is arranged straight along the radial direction.

2. The electric machine (1000) according to claim 1, characterized in that The cooling pipeline (2) comprises a plurality of Tesla valve structures (21), and each of the Tesla valve structures (21) is connected end to end.

3. The electric machine (1000) according to claim 1, characterized in that: A line connecting the inlet (2a) and the outlet (2b) is parallel to a straight line extending in the direction of the rotation axis of the stator and rotor (1).

4. A method for testing the cooling effect of a motor, characterized in that: The motor cooling effect testing method is applied to the motor (1000) as claimed in claim 1; the number of Tesla valve structures (21) in the cooling pipe (2) and the width of the direct current channel (22) extending in the radial direction are adjusted, and a heat dissipation simulation test is performed on the adjusted motor (1000), and the motor cooling effect is generated according to the test results.

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