A phase change material and oil cooling combined circulation cooling structure

Abstract

The present invention relates to the field of motor cooling technology, and in particular to a phase change material and oil cooling combined circulation cooling structure. It comprises a motor housing, an oil collecting tank is arranged inside the bottom plate of the motor housing, and cooling oil is stored inside the oil collecting tank; cooling is performed through a second heat exchanger, and an oil pump is introduced into the cooling oil circuit and the phase change circulation cooling layer; the cooling oil circuit is located outside the phase change circulation cooling layer; the phase change circulation cooling layer comprises a cooling phase change layer located on the outer layer and a heat exchange phase change layer located on the inner layer; phase change material is arranged inside both the cooling phase change layer and the heat exchange phase change layer. The present invention can effectively cool down the stator core and reduce the impact of motor temperature rise by arranging the phase change material between the cooling phase change layer and the heat exchange phase change layer, and has a good effect on maintaining the temperature of the motor; heat is dissipated by combining the phase change material and oil cooling, so as to achieve rapid cooling of the motor and improve the working performance of the motor.

Description

Technical Field

[0001] The invention relates to the technical field of motor cooling, and in particular to a phase change material and oil cooling combined circulating cooling structure. Background Art

[0002] As the world pays more attention to and develops new energy vehicles, the pressure on energy, environment and safety is increasing. The power density and torque of motors have become the focus of research and development, but the temperature rise of motors is one of the major factors that limit the motors from exerting high power and torque.

[0003] To solve the temperature rise of motors, air cooling, water cooling and oil cooling technologies are constantly being improved and innovated. Since the operating temperature of motors is relatively high, direct cooling with too low oil temperature has a great impact on the performance and life of motors. The heat dissipation solution that uses phase change elements to build additional heat paths is a new idea for the efficient development of motor heat dissipation systems.

[0004] Phase change thermal management technology can effectively extend the stable operation time of the motor, suppress the temperature rise of the motor, and achieve efficient heat dissipation of the motor. However, the current design using phase change materials as cooling media rarely considers circulating cooling, and cannot effectively continue to cool the motor after long-term operation.

[0005] Therefore, we propose a phase change material and oil cooling combined circulation cooling structure of the present invention, which combines oil cooling with phase change cooling technology to achieve rapid cooling of the motor and improve the working performance of the motor. Summary of the invention

[0006] The object of the present invention is to provide a phase change material and oil cooling combined circulating cooling structure.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A phase change material and oil cooling combined circulation cooling structure, comprising a motor housing, a rotating shaft is rotatably connected to the central axis of the motor housing, a rotor is installed on the outer side of the rotating shaft; a stator core is also fixed on the inner side wall of the motor housing and centered on the rotating shaft, and a winding is arranged on the stator core;

[0009] An oil collecting tank is provided inside the bottom plate of the motor housing, and cooling oil is stored inside the oil collecting tank;

[0010] Also included is an oil pump disposed outside the motor housing;

[0011] The input end of the oil pump is connected to the oil collecting tank through an oil return pipeline;

[0012] The output end of the oil pump is connected to a second oil inlet pipeline, and the second oil inlet pipeline is connected to a second heat exchanger for cooling the coolant;

[0013] An oil inlet hole is also provided on the top of the motor housing, and the oil inlet hole is connected to the output port of the second oil inlet pipeline;

[0014] A cooling oil circuit and a phase change circulation cooling layer are also installed between the stator core and the motor housing, and the cooling oil circuit is located outside the phase change circulation cooling layer;

[0015] The phase change circulation cooling layer includes a cooling phase change layer located at the outer layer and a heat exchange phase change layer located at the inner layer;

[0016] The cooling phase change layer and the heat exchange phase change layer are both hollow layers, and the top and bottom thereof are connected through a phase change cycle inlet and a phase change cycle outlet, respectively; the cooling phase change layer and the heat exchange phase change layer are both provided with phase change materials inside;

[0017] The cooling oil circuit is a hollow annular tube, the top of the cooling oil circuit is connected to the oil inlet hole, the bottom of the motor housing is also provided with a first oil return hole, and the bottom of the cooling oil circuit is connected to the first oil return hole;

[0018] The first oil return hole is connected to the oil collecting tank.

[0019] Furthermore, a filter is installed on the oil return pipeline.

[0020] Furthermore, the oil pump output end is connected to the second oil inlet pipeline through an output interface of a three-way joint;

[0021] The oil pump output end is also connected to the first oil inlet pipeline through another output interface of the three-way joint;

[0022] The first oil inlet pipeline is connected to a first heat exchanger for cooling the cooling oil; the output port of the first oil inlet pipeline is connected to two flow-dividing pipelines;

[0023] Two oil collecting passages are arranged at positions corresponding to the two ends of the winding on both sides of the top of the motor housing, and the two oil collecting passages are connected to the two diversion pipelines. An oil spray hole is also arranged at the bottom of the oil collecting passage for spraying cooling oil to the winding.

[0024] Furthermore, a plurality of second oil return holes are formed at the bottom of the motor housing, and the second oil return holes are connected to the oil collecting tank.

[0025] Furthermore, the materials of the cooling phase change layer and the heat exchange phase change layer are heat-resistant, heat-conductive and non-conductive solid materials.

[0026] Furthermore, the cooling phase change layer and the heat exchange phase change layer are made of ceramic materials.

[0027] Furthermore, the phase change material is paraffin.

[0028] Furthermore, the circumferential gap between the cooling phase change layer and the heat exchange phase change layer is filled with a heat insulating material;

[0029] Thermal conductive silicone grease is filled between the cooling oil circuit and the cooling phase change layer.

[0030] Furthermore, the cooling oil circuit is made of silica gel or thermally conductive ceramic material.

[0031] Furthermore, the thermal insulation material is asbestos and / or glass fiber.

[0032] The present invention has at least the following beneficial effects:

[0033] The present invention can effectively cool the stator core and reduce the impact of motor temperature rise by arranging a phase change material between the cooling phase change layer and the heat exchange phase change layer, as well as designing its circulation structure. It has a good effect on maintaining the temperature of the motor and can solve the problem of high-temperature operation of the motor, slow cooling of the cooling oil, and inability to use low-temperature cooling oil for cooling under peak motor operating conditions.

[0034] The present invention can also dissipate heat for the winding by spraying, thereby further ensuring the heat dissipation efficiency of the motor and maintaining the temperature of the motor.

[0035] The present invention combines phase change material with oil cooling to dissipate heat, thereby achieving rapid cooling of the motor and improving the working performance of the motor.

[0036] The phase change material of the present invention adopts paraffin, which can well reduce costs and reduce environmental pollution.

[0037] The use of the circulating cooling of the present invention enables the phase change material to repeatedly participate in the heat exchange reaction, and when the motor is not running, at room temperature, the paraffin can still release heat and become solid, so as to participate in the heat exchange reaction in time when restarting.

[0038] The present invention uses materials such as thermally conductive silicone grease, thermally conductive silica gel and thermally conductive ceramics to better increase heat conduction, and the materials have no effect on the magnetic field of the motor and can well fit the structure required for the cycle reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0040] Figure 1 It is an overall schematic diagram of the present invention;

[0041] Figure 2 Side view of the installation of cooling layer for phase change circulation;

[0042] Figure 3 This is a cross-sectional diagram of the phase change cycle cooling layer.

[0043] In the figure: 1. first heat exchanger; 2. first oil inlet pipeline; 3. second heat exchanger; 4. shunt pipeline; 5. oil collecting pipeline; 6. oil spray hole; 7. oil inlet hole; 8. cooling oil circuit; 9. phase change circulation cooling layer; 10. stator core; 11. rotor; 12. rotating shaft; 13. first oil return hole; 14. second oil return hole; 15. oil collecting tank; 16. oil return pipeline; 17. filter; 18. oil pump; 19. winding; 20. three-way joint; 21. second oil inlet pipeline; 22. cooling phase change layer; 23. heat exchange phase change layer; 24. phase change circulation inlet; 25. phase change circulation outlet; 26. motor housing. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0045] Reference Figure 1 The present invention provides a phase change material and oil cooling combined circulating cooling structure.

[0046] It includes a motor housing 26, wherein a rotating shaft 12 is rotatably connected to the inner central axis of the motor housing 26, and a rotor 11 is installed on the outer side of the rotating shaft 12; a stator core 10 is also fixed on the inner side wall of the motor housing 26 and centered on the rotating shaft 12, and a winding 19 is arranged on the stator core 10.

[0047] The above are all existing conventional motor structures. The purpose of the present invention is to cool the motor, achieve rapid cooling of the motor, and improve the working performance of the motor.

[0048] Specifically, the design of the present invention is as follows:

[0049] An oil collecting tank 15 is provided inside the bottom plate of the motor housing 26, and cooling oil is stored inside the oil collecting tank 15;

[0050] The present invention further comprises an oil pump 18 disposed outside the motor housing 26, the input end of the oil pump 18 being connected to the oil collecting tank 15 via an oil return line 16 for extracting the cooling oil therein;

[0051] In one embodiment, a filter 17 is further installed on the oil return pipeline 16 for filtering the cooling oil.

[0052] The output end of the oil pump 18 is connected to a three-way joint 20, one output interface of the three-way joint 20 is connected to the first oil inlet pipeline 2, and the other output interface of the three-way joint 20 is connected to the second oil inlet pipeline 21;

[0053] The first oil inlet pipeline 2 is connected to the first heat exchanger 1, and the coolant is cooled by the first heat exchanger 1;

[0054] The output port of the first oil inlet pipeline 2 is connected to two flow diversion pipelines 4;

[0055] Two oil collecting passages 5 are provided at positions corresponding to the two ends of the winding 19 on both sides of the top of the motor housing 26, and the two oil collecting passages 5 are connected to the two flow diversion pipelines 4;

[0056] The bottom of the oil collecting passage 5 is also provided with an oil spray hole 6 for spraying cooling oil toward the winding 19 .

[0057] In combination with the above, it can be known that: under the action of the oil pump 18, the cooling oil enters the oil return pipeline 16 from the oil collecting tank 15, and the oil return pipeline 16 is connected to the filter 17, and the filter 17 filters the impurities in the cooling oil; then the cooling oil is divided into the first oil inlet pipeline 2 and the second oil inlet pipeline 21 through the three-way joint;

[0058] Among them, the first oil inlet pipeline 2 is connected to the first heat exchanger 1, and the coolant is cooled by the first heat exchanger 1. The heat exchanger is connected to the diversion pipeline 4 through an oil pipe, and the cooling oil is diverted here and enters the tops of the windings 19 on both sides respectively; then the cooling oil enters the oil collecting circuit 5, and completes the spray cooling of the winding 19 through the oil spray hole 6.

[0059] The bottom of the motor housing 26 is further provided with a plurality of second oil return holes 14 , and the second oil return holes 14 are connected to the oil collecting tank 15 .

[0060] Thus, the cooling oil that has completed the spray cooling enters the second oil return hole 14 at the bottom and enters the oil collecting tank 15 to complete the circulation.

[0061] The above is the cooling method for the winding 19.

[0062] The second oil inlet pipeline 21 is connected to the second heat exchanger 3 for cooling the coolant.

[0063] The top of the motor housing 26 is also provided with an oil inlet hole 7 , and the oil inlet hole 7 is connected to the output port of the second oil inlet pipeline 21 .

[0064] See also Figure 2 :

[0065] A cooling oil circuit 8 and a phase change circulation cooling layer 9 are also installed between the stator core 10 and the motor housing 26, and the cooling oil circuit 8 is located outside the phase change circulation cooling layer 9;

[0066] The phase change circulation cooling layer 9 includes a cooling phase change layer 22 located at the outer layer and a heat exchange phase change layer 23 located at the inner layer;

[0067] The cooling phase change layer 22 and the heat exchange phase change layer 23 are made of heat-resistant, heat-conductive and non-conductive solid materials, and ceramics may be selected as the material.

[0068] See also Figure 3 The cooling phase change layer 22 and the heat exchange phase change layer 23 are both hollow layers, and their tops and bottoms are connected through a phase change cycle inlet 24 and a phase change cycle outlet 25 respectively; phase change materials are arranged inside the cooling phase change layer 22 and the heat exchange phase change layer 23.

[0069] The circumferential gap between the cooling phase change layer 22 and the heat exchange phase change layer 23 is filled with a heat insulating material (optionally asbestos or glass fiber) to prevent the temperature of the heat exchange phase change layer 23 from being transferred to the cooling phase change layer 22 and affecting the cooling efficiency.

[0070] The second heat exchanger 3 cools down the cooling oil according to the needs of phase change cycle cooling, so that the phase change material is fully transformed into a solid state when entering the cooling phase change layer 22 .

[0071] The heat exchange phase change layer 23 contacts the stator core 10 to exchange heat; the heat exchange phase change layer 23 is filled with a phase change material, which is paraffin wax. The paraffin wax absorbs heat and becomes liquid. During the liquefaction process, the temperature of the stator core 10 is controlled at the phase change reaction temperature. The liquid paraffin wax increases in density and enters the phase change circulation outlet 25 downward, and gradually falls to the bottom of the cooling phase change layer 22.

[0072] After the solid paraffin in the cooling phase change layer 22 increases in the liquid paraffin at the bottom, it gradually moves upwards with a lower density, enters the phase change circulation inlet 24, and enters the heat exchange phase change layer 23 at the inlet. In addition, the liquid paraffin entering the bottom exchanges heat with the external cooling oil circuit 8, releases heat again and becomes solid.

[0073] The cooling oil circuit 8 is a hollow annular tube, which can be made of materials such as silicone tubes and thermal conductive ceramic tubes. The top of the cooling oil circuit 8 is connected to the oil inlet hole 7. The bottom of the motor housing 26 is also provided with a first oil return hole 13, and the bottom of the cooling oil circuit 8 is connected to the first oil return hole 13.

[0074] The first oil return hole 13 is connected to the oil collecting groove 15 .

[0075] Thus: under the action of the oil pump 18, the cooling oil is cooled through the second heat exchanger 3, and then enters the cooling oil circuit 8 to flow in a circular manner; the cooling oil circuit 8 cools the cooling phase change layer 22 on the outside; at the same time, thermal conductive silicone grease can be arranged between the cooling oil circuit 8 and the cooling phase change layer 22 to increase thermal conductivity; the outside of the cooling phase change layer 22 is in contact with the cooling oil circuit 8 to ensure that the phase change material in the circumference remains in a solid state; at the same time, through the heat exchange between the cooling phase change layer 22 and the heat exchange phase change layer 23, as well as the heat exchange between the heat exchange phase change layer 23 and the stator core 10, and the liquefaction and solidification of the phase change material itself, the stator core 10 is kept at the phase change reaction temperature; at the same time, the cooling oil that subsequently undergoes heat exchange enters the first oil return hole 13 at the bottom oil return hole and enters the oil collecting tank 15 to complete the cycle.

[0076] Therefore, combined with the above, we can know that:

[0077] The present invention can effectively cool the stator core 10 by setting a phase change material setting between the cooling phase change layer 22 and the heat exchange phase change layer 23, and designing its circulation structure, which can reduce the impact of motor temperature rise and has a good effect on maintaining the temperature of the motor. It can also solve the problem that under the peak working condition of the motor, the motor runs at high temperature, the cooling oil cools down slowly, and low-temperature cooling oil cannot be used for cooling.

[0078] The present invention can also dissipate heat for the winding 19 by spraying, thereby further ensuring the heat dissipation efficiency of the motor and maintaining the temperature of the motor.

[0079] The present invention combines phase change material and oil cooling to dissipate heat, achieves rapid cooling of the motor, and improves the working performance of the motor

[0080] The phase change material of the present invention adopts paraffin, which can well reduce costs and reduce environmental pollution.

[0081] The use of the circulating cooling of the present invention enables the phase change material to repeatedly participate in the heat exchange reaction, and when the motor is not running, at room temperature, the paraffin can still release heat and become solid, so as to participate in the heat exchange reaction in time when restarting.

[0082] The present invention uses materials such as thermally conductive silicone grease, thermally conductive silica gel and thermally conductive ceramics to better increase heat conduction, and the materials have no effect on the magnetic field of the motor and can well fit the structure required for the cycle reaction.

[0083] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A phase change material and oil cooling combined circulating cooling structure, characterized in that: The motor comprises a motor housing (26), wherein a rotating shaft (12) is rotatably connected to the central axis of the motor housing (26), and a rotor (11) is mounted on the outer side of the rotating shaft (12); a stator core (10) is fixed on the inner side wall of the motor housing (26) and centered on the rotating shaft (12), and a winding (19) is arranged on the stator core (10); An oil collecting tank (15) is provided inside the bottom plate of the motor housing (26), and cooling oil is stored inside the oil collecting tank; Also included is an oil pump (18) disposed outside the motor housing (26); The input end of the oil pump (18) is connected to the oil collecting tank (15) via an oil return pipeline (16); The output end of the oil pump (18) is connected to a second oil inlet pipeline (21), and the second oil inlet pipeline (21) is connected to a second heat exchanger (3) for cooling the coolant; The top of the motor housing (26) is also provided with an oil inlet hole (7), and the oil inlet hole (7) is connected to the output port of the second oil inlet pipeline (21); A cooling oil circuit (8) and a phase change circulation cooling layer (9) are also installed between the stator core (10) and the motor housing (26), and the cooling oil circuit (8) is located outside the phase change circulation cooling layer (9); The phase change circulation cooling layer (9) comprises a cooling phase change layer (22) located at an outer layer and a heat exchange phase change layer (23) located at an inner layer; The cooling phase change layer (22) and the heat exchange phase change layer (23) are both hollow layers, and the top and bottom thereof are connected respectively via a phase change circulation inlet (24) and a phase change circulation outlet (25); the cooling phase change layer (22) and the heat exchange phase change layer (23) are both provided with phase change materials inside; The cooling oil circuit (8) is a hollow annular tube, the top of the cooling oil circuit (8) is connected to the oil inlet hole (7), the bottom of the motor housing (26) is also provided with a first oil return hole (13), and the bottom of the cooling oil circuit (8) is connected to the first oil return hole (13); The first oil return hole (13) is connected to the oil collecting tank (15).

2. The phase change material and oil cooling combined circulation cooling structure according to claim 1, characterized in that: A filter (17) is also installed on the oil return pipeline (16).

3. The phase change material and oil cooling combined circulating cooling structure according to claim 1 is characterized in that: The output end of the oil pump (18) is connected to the second oil inlet pipeline (21) via an output interface of a three-way joint (20); The output end of the oil pump (18) is also connected to the first oil inlet pipeline (2) via another output interface of the three-way connector (20); The first oil inlet pipeline (2) is connected to a first heat exchanger (1) for cooling the cooling oil; the output port of the first oil inlet pipeline (2) is connected to two flow-dividing pipelines (4); Two oil collecting passages (5) are arranged at positions corresponding to the two ends of the winding (19) on both sides of the top of the motor housing (26), and the two oil collecting passages (5) are connected to the two flow-dividing pipelines (4). An oil spray hole (6) is also arranged at the bottom of the oil collecting passage (5) for spraying cooling oil toward the winding (19).

4. The phase change material and oil cooling combined circulation cooling structure according to claim 3 is characterized in that: A plurality of second oil return holes (14) are also provided at the bottom of the motor housing (26), and the second oil return holes (14) are connected to the oil collecting tank (15).

5. The phase change material and oil cooling combined circulating cooling structure according to claim 1 is characterized in that: The materials of the cooling phase change layer (22) and the heat exchange phase change layer (23) are heat-resistant, heat-conductive and non-conductive solid materials.

6. A phase change material and oil cooling combined circulation cooling structure according to claim 5, characterized in that: The cooling phase change layer (22) and the heat exchange phase change layer (23) are made of ceramic materials.

7. The phase change material and oil cooling combined circulating cooling structure according to claim 1, characterized in that: The phase change material is paraffin.

8. The phase change material and oil cooling combined circulating cooling structure according to claim 1, characterized in that: The circumferential gap between the cooling phase change layer (22) and the heat exchange phase change layer (23) is filled with a heat insulation material; Thermally conductive silicone grease is filled between the cooling oil circuit (8) and the cooling phase change layer (22).

9. The phase change material and oil cooling combined circulation cooling structure according to claim 1, characterized in that: The cooling oil circuit (8) is made of silica gel or heat-conducting ceramic material.

10. The phase change material and oil cooling combined circulation cooling structure according to claim 8, characterized in that: The thermal insulation material is asbestos and / or glass fiber.

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