Motor cooling structure and system, vehicle and motor cooling method

Abstract

The invention relates to the technical field of vehicles, in particular to a motor cooling structure and system, a vehicle and a motor cooling method. The structure comprises a stator core and a stator winding arranged on the stator core, the multi-layer oil injection assembly is arranged on the first part of the stator winding and used for injecting axial multi-layer cooling oil to cool the upper half part of the outer ring of the stator winding; and the oil guide groove is fixed at the second part of the stator winding and is used for guiding the cooling oil sprayed from the upper half part to cool the lower half part of the outer ring of the stator winding. Therefore, the problems of low heat dissipation efficiency, poor cooling effect and the like existing in a water-based cooling or oil injection cooling mode in the prior art are solved.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a motor cooling structure, system, vehicle and motor cooling method. Background Art

[0002] With the increasing global awareness of environmental protection and the need for energy structure transformation, new energy vehicles have developed rapidly as one of the effective means to reduce carbon emissions and improve air quality. New energy vehicles include pure electric vehicles, plug-in hybrid vehicles and other types. These vehicles rely on high-voltage motor systems to achieve driving, power generation or hybrid functions. High-voltage motors generate a lot of heat during operation, mainly from copper loss in stator windings, iron loss in cores and other stray losses. If this heat cannot be dissipated in a timely and effective manner, it will cause the winding temperature to rise, thereby affecting the performance and life of the motor. High temperature may not only cause aging and deformation of the winding insulation material, but may even cause fire accidents, so appropriate cooling measures must be taken to keep the winding within a safe operating temperature range.

[0003] The related technology removes heat by introducing cooling water into the circulation channel inside the motor. However, because water is corrosive and conductive, it cannot directly contact the stator core and winding components, which results in a long heat conduction path and high thermal resistance, and low heat dissipation efficiency. Alternatively, by opening an oil spray hole on the surface of the stator core or the surface of the motor housing, or by installing an oil spray ring separately, the cooling oil is sprayed onto the outer ring of the stator winding for rapid cooling, but there is still a problem of poor cooling effect. Summary of the invention

[0004] The present application provides a motor cooling structure, system, vehicle and motor cooling method to solve the problems of low heat dissipation efficiency and poor cooling effect in the related art through water-based cooling or oil-spray cooling.

[0005] The first aspect of the present application provides a motor cooling structure, including: a stator core and a stator winding arranged on the stator core; a multi-layer oil spray assembly, the multi-layer oil spray assembly is arranged in the first part of the stator winding, and is used to spray axial multi-layer cooling oil to cool the upper half of the outer ring of the stator winding; an oil guide groove, fixed at the second part of the stator winding, and is used to guide the cooling oil sprayed from the upper half to cool the lower half of the outer ring of the stator winding.

[0006] Optionally, the motor cooling structure further includes: an oil return hole arranged at the bottom of the oil guide groove, for returning the cooling oil to the cooling oil pump through the oil return hole.

[0007] Optionally, the oil guide groove is fixed by snap-on fixing of the molded part or by coating and curing of the thermally conductive insulating material.

[0008] Optionally, the oil guide groove is injection molded from insulating material.

[0009] Optionally, it also includes: a rotor and a plurality of oil holes arranged on the rotor, and the cooling oil is splashed from the plurality of oil holes onto the inner ring of the stator winding through the centrifugal force generated when the rotor rotates at high speed, so as to cool the inner ring of the stator winding.

[0010] The second aspect of the present application provides a motor cooling system, including: the motor cooling structure of the above embodiment; a detection component for detecting the operating temperature of the motor; a controller for determining the flow and pressure of the cooling oil according to the operating temperature, and controlling the multi-layer oil spray assembly to spray axial multi-layer cooling oil to cool the upper half of the outer ring of the stator winding according to the flow and pressure, and using the oil guide groove to guide the cooling oil sprayed from the upper half to cool the lower half of the outer ring of the stator winding.

[0011] A third aspect of the present application provides a vehicle, including: a motor cooling system as described in the above embodiment.

[0012] The fourth aspect embodiment of the present application provides a motor cooling method, which is based on the motor cooling structure for cooling, and includes the following steps: obtaining the operating temperature of the motor; determining the flow rate and pressure of the cooling oil according to the operating temperature; controlling the multi-layer oil spray assembly to spray axial multi-layer cooling oil to cool the upper half of the outer ring of the stator winding according to the flow rate and pressure, and using the oil guide groove to guide the cooling oil sprayed from the upper half to cool the lower half of the outer ring of the stator winding.

[0013] Optionally, determining the flow rate and pressure of the cooling oil according to the operating temperature includes: obtaining a correspondence table of the operating temperature, the cooling oil flow rate and the cooling oil pressure; and determining the flow rate and pressure of the cooling oil according to the correspondence table and the operating temperature.

[0014] A fifth aspect of the present application provides a computer-readable storage medium having a computer program or instruction stored thereon. When the computer program or instruction is executed, it is used to implement the motor cooling method as described in the above embodiment.

[0015] Therefore, this application has at least the following beneficial effects:

[0016] The embodiment of the present application adds an oil guide groove at the second part of the stator winding, so that the cooling oil can naturally flow through the lower half area to take away more heat, and the method of spraying axial multi-layer cooling oil based on the multi-layer oil spray assembly improves the cooling effect and reduces the failure rate caused by heat dissipation problems. Therefore, the problems of low heat dissipation efficiency and poor cooling effect in the related art through water-based cooling or oil spray cooling are solved.

[0017] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0019] Figure 1 This is a simplified axial schematic diagram of a motor cooling structure provided according to an embodiment of the present application;

[0020] Figure 2 It is a detailed axial schematic diagram of a motor cooling structure provided according to an embodiment of the present application;

[0021] Figure 3 A schematic diagram of a central cross-section of a rotating shaft of a motor provided according to an embodiment of the present application;

[0022] Figure 4 The present invention is a flow chart of a motor cooling method provided according to an embodiment of the present application.

[0023] Figure 5 The block diagram of the motor cooling system provided according to the embodiment of the present application.

[0024] Explanation of the reference numerals: stator core 101, stator winding 102, oil guide groove 103, motor housing 201, rotor core 202, motor shaft 203, rotor end cover 204, oil return hole 205, rotor cooling oil channel 206, oil beam splashing from the outer ring of the stator winding 207, oil beam splashing from the inner ring of the stator winding 208 and stator core oil channel 209. DETAILED DESCRIPTION

[0025] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0026] The motor cooling structure, system, vehicle and motor cooling method of the embodiments of the present application are described below with reference to the accompanying drawings. In response to the problems mentioned in the above background technology, the present application provides a motor cooling structure, which adds an oil guide groove at the second part of the stator winding so that the cooling oil can flow naturally through the lower region to take away more heat, and the method of spraying axial multi-layer cooling oil based on the multi-layer oil spray assembly improves the cooling effect and reduces the failure rate caused by heat dissipation problems. As a result, the problems of low heat dissipation efficiency and poor cooling effect in the related technology through water-based cooling or oil spray cooling are solved.

[0027] Specifically, Figure 1 It is an axial schematic diagram of the motor cooling structure of an embodiment of the present application.

[0028] like Figure 1 As shown, the motor cooling structure mainly includes: a stator core 101, a stator winding 102, a multi-layer oil injection assembly and an oil guide groove 103.

[0029] The stator winding 102 is arranged on the stator core 101, and the multi-layer oil spray assembly is arranged on the first part of the stator winding 102, which is used to spray axial multi-layer cooling oil to cool the upper half of the outer ring of the stator winding 102; the oil guide groove 103 is fixed at the second part of the stator winding 102 (such as Figure 1 The portion below the dotted line in the horizontal direction shown in the figure) is used to guide the cooling oil sprayed from the upper portion to cool the lower portion of the outer ring of the stator winding 102.

[0030] In the embodiments of the present application, Figure 1 The dotted line in the horizontal direction can divide the stator winding 102 into a first part and a second part, wherein the part above the dotted line is the first part and the part below the dotted line is the second part. The motor can be a high-voltage drive motor, a generator or a hybrid motor. The motor includes permanent magnet synchronous motor, switched reluctance motor, AC asynchronous motor and other motor types. The motor structure mainly includes an external stator form.

[0031] like Figure 1 The axial front view of the motor end is shown. The conventional components of the motor of the embodiment of the present application are assembled according to normal logic, mainly adding an oil guide groove 103. The oil guide groove 103 can be injection molded using insulating materials such as nylon and PPS, or insulating materials with better thermal conductivity can be used to achieve better results. The fixing method is that the oil guide groove 103 is clamped at the lower half of the winding end with its own clip; the insulating or thermally conductive material can also be coated on the outer ring and the end of the lower half of the stator winding 102 in a liquid or molten state, and after certain conditions, it is solidified to form a certain thickness. Figure 1 The oil guide groove 103 structure shown forms a similar immersion cooling effect on the lower half shaft winding end. The multi-layer oil spray assembly can be a series of oil spray holes or oil spray rings, which are located in the upper half of the stator winding 102 for spraying cooling oil.

[0032] Furthermore, if Figure 2 and Figure 3As shown, it also includes a motor housing 201, a rotor core 202, a rotor end cover 204, a motor shaft 203, an oil return hole 205, a rotor cooling oil channel 206, a stator core oil channel 209, etc. Among them, the motor housing 201 is the main outer shell of the motor, usually made of metal materials, and plays a role in supporting and protecting internal components. The stator core 101 is usually made of stacked silicon steel sheets, has good magnetic properties, and is used as a carrier of the magnetic field. The stator winding 102 is wound on the stator core 101, and generates a magnetic field after power is turned on, and works together with the rotor to drive the motor to operate. The cooling water channel surrounds the motor housing and takes away the heat generated by the motor during operation by conductive heat dissipation. The oil beam splashed from the outer ring of the stator winding 102 in the embodiment of the present application is shown as follows. Figure 2 207, and the oil beam splashed from the inner ring of the stator winding 102 as shown Figure 2 208 shown. In addition, Figure 2 and Figure 3 The other components shown in the figure (such as the rotor core 202) are conventional components of the motor and will not be described again here.

[0033] It is understandable that if Figure 2 and Figure 3 As shown, the multi-layer oil injection assembly of the embodiment of the present application is mainly optimized by optimizing the oil injection position and method. At present, the oil injection cooling outer ring is a full circle of 360 degrees, and the axial direction is a layer. The outer ring oil injection position is optimized in the embodiment of the present application, and the single-layer oil injection of a full circle is changed to the multi-layer axial oil injection of the upper half circle, which can more fully cool the axial parts of the stator winding 102. At the same time, the cooling oil is sprayed downward, and the required oil pressure is reduced. Therefore, the power of the oil pump can be reduced accordingly. At the same time, the oil channel and the oil injection hole can also be optimized and shortened to reduce the complexity of the oil channel. Secondly, after the cooling oil in the upper half circle takes away a part of the heat, due to the action of gravity, the cooling oil naturally flows into the oil guide groove 103 of the lower half circle. During the flow process of the oil guide groove 103, the heat of the lower half circle is taken away, and finally flows out through the bottom oil return hole 205. Because the flow path is long, the cooling oil is fully in contact with the winding and takes away more heat.

[0034] In one embodiment of the present application, Figure 2 As shown, the motor cooling structure 10 further includes: an oil return hole 205 disposed at the bottom of the oil guide groove 103, for returning the cooling oil to the cooling oil pump through the oil return hole 205, thereby realizing recycling and ensuring continuous and efficient operation of the cooling system;

[0035] In one embodiment of the present application, the motor cooling structure 10 also includes: a rotor and a plurality of oil holes arranged on the rotor. The centrifugal force generated when the rotor rotates at high speed splashes the cooling oil from the plurality of oil holes onto the inner ring of the stator winding 102, thereby cooling the inner ring of the stator winding 102 to ensure that the entire winding (including the inner ring and the outer ring) can be effectively cooled, thereby improving the cooling efficiency.

[0036] In summary, the embodiments of the present application improve the cooling structure of the drive motor or generator of a new energy vehicle to improve cooling efficiency, enhance product reliability and life, and reduce size and cost. The details are as follows:

[0037] 1. Improve cooling effect, reduce the failure rate caused by heat dissipation problems, and improve product reliability and life;

[0038] 2. Increased heat dissipation capacity can increase the peak power and continuous power of the product, and improve the power density of the product;

[0039] 3. Compared with other cooling methods, under the same power density requirement, the size of the product can be reduced, which can reduce the weight and cost;

[0040] 4. A smaller oil pump can be used to achieve low pressure drop and energy consumption, thus increasing the vehicle's mileage.

[0041] According to the motor cooling structure proposed in the embodiment of the present application, an oil guide groove is added so that the cooling oil can naturally flow through the lower half of the stator winding to take away more heat. The method of spraying axial multi-layer cooling oil based on a multi-layer oil spray assembly improves the cooling effect and reduces the occurrence rate of failures caused by heat dissipation problems.

[0042] Next, the motor cooling method proposed according to the embodiment of the present application is described with reference to the accompanying drawings.

[0043] Figure 4 A schematic flow chart of a motor cooling method provided in an embodiment of the present application.

[0044] like Figure 4 As shown, the motor cooling method includes the following steps:

[0045] In step S101 , the operating temperature of the motor is obtained.

[0046] The embodiment of the present application can monitor the real-time temperature inside the motor, especially the stator winding, through temperature sensors. These sensors can be installed in the stator core, winding or other key positions to ensure accurate measurement of the operating temperature under actual working conditions.

[0047] In step S102, the flow rate and pressure of the cooling oil are determined according to the operating temperature.

[0048] In an embodiment of the present application, the flow rate and pressure of the cooling oil are determined according to the operating temperature, including: obtaining a correspondence table of the operating temperature, the cooling oil flow rate and the cooling oil pressure; and determining the flow rate and pressure of the cooling oil according to the correspondence table and the operating temperature.

[0049] The embodiment of the present application needs to establish a data table about the relationship between the motor operating temperature, cooling oil flow rate and cooling oil pressure, which is based on experimental data or theoretical calculations and reflects the optimal cooling oil flow rate and pressure settings at different temperatures. For example, at lower temperatures, very high cooling oil flow rate and pressure may not be required; at higher temperatures, the flow rate and pressure need to be increased to ensure sufficient cooling effect.

[0050] Furthermore, after obtaining the actual operating temperature of the current motor, the embodiment of the present application can use this temperature value as input to query a pre-set correspondence table to find the optimal cooling oil flow and pressure value corresponding to the temperature.

[0051] In step S103, the multi-layer oil spray assembly is controlled to spray axial multi-layer cooling oil to cool the upper half of the outer ring of the stator winding according to the flow rate and pressure, and the cooling oil sprayed from the upper half is guided by the oil guide groove to cool the lower half of the outer ring of the stator winding.

[0052] The embodiment of the present application can control the upper half of the outer ring of the stator winding of the multi-layer oil spray assembly to spray multiple layers of cooling oil according to the determined optimal cooling oil flow and pressure values. In this way, the axial parts of the winding can be cooled more concentratedly, thereby improving the cooling efficiency. After taking away a part of the heat, the cooling oil sprayed from the upper half circle naturally flows into the oil guide groove arranged at the lower half of the stator winding due to the effect of gravity. The design of the oil guide groove enables the cooling oil to flow along a specific path, thereby effectively contacting the lower half of the outer ring of the stator winding, further enhancing the cooling effect of the entire winding area. This design not only ensures that the cooling oil is in full contact with the winding surface, but also increases the heat exchange area through a longer flow path, thereby improving the heat dissipation capacity.

[0053] In addition, the present application embodiment also provides a motor cooling system 20, such as Figure 5 As shown, it includes: the motor cooling structure of the above embodiment; a detection component 201 is used to detect the operating temperature of the motor; a controller 202 is used to determine the flow rate and pressure of the cooling oil according to the operating temperature, and control the multi-layer oil injection component to spray axial multi-layer cooling oil to cool the upper half of the outer ring of the stator winding according to the flow rate and pressure, and use the oil guide groove to guide the cooling oil sprayed from the upper half to cool the lower half of the outer ring of the stator winding.

[0054] It should be noted that some of the above explanations of the motor cooling structure and the motor cooling method embodiments are also applicable to the motor cooling system of this embodiment, and will not be repeated here.

[0055] An embodiment of the present application provides a vehicle, including: a motor cooling system as described in the above embodiment.

[0056] An embodiment of the present application also provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the above motor cooling method is implemented.

[0057] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0058] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0059] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0060] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array, a field programmable gate array, etc.

[0061] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0062] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A motor cooling structure, characterized in that: include: A stator core and a stator winding arranged on the stator core; A multi-layer oil spray assembly, which is arranged at the first part of the stator winding and is used to spray axial multi-layer cooling oil to cool the upper half of the outer ring of the stator winding; An oil guide groove is fixed at the second part of the stator winding and is used to guide the cooling oil sprayed from the upper part to cool the lower part of the outer ring of the stator winding.

2. The motor cooling structure according to claim 1, characterized in that: Also includes: The oil return hole arranged at the bottom of the oil guide groove is used to return the cooling oil to the cooling oil pump through the oil return hole.

3. The motor cooling structure according to claim 1, characterized in that: The oil guide groove is fixed by snap-on fixing of the molded part or by coating and curing of the heat-conducting insulating material.

4. The motor cooling structure according to claim 1, characterized in that: The oil guide groove is injection-molded by insulating material.

5. The motor cooling structure according to claim 1, characterized in that: Also includes: The rotor and the plurality of oil holes arranged on the rotor splash cooling oil from the plurality of oil holes onto the inner ring of the stator winding through the centrifugal force generated when the rotor rotates at a high speed, thereby cooling the inner ring of the stator winding.

6. A motor cooling system, characterized in that: include: The motor cooling structure according to any one of claims 1 to 5; A detection component, used to detect the operating temperature of the motor; The controller is used to determine the flow rate and pressure of the cooling oil according to the operating temperature, and control the multi-layer oil spray assembly to axially spray the multi-layer cooling oil to cool the upper half of the outer ring of the stator winding according to the flow rate and the pressure, and use the oil guide groove to guide the cooling oil sprayed from the upper half to cool the lower half of the outer ring of the stator winding.

7. A vehicle, characterized in that: include: The motor cooling system as claimed in claim 6.

8. A motor cooling method, characterized in that: The method is based on the motor cooling structure according to any one of claims 1 to 5 for cooling, and comprises the following steps: Get the operating temperature of the motor; determining the flow rate and pressure of the cooling oil according to the operating temperature; The multi-layer oil spray assembly is controlled to spray axial multi-layer cooling oil to cool the upper half of the stator winding outer ring according to the flow rate and the pressure, and the cooling oil sprayed from the upper half is guided by the oil guide groove to cool the lower half of the stator winding outer ring.

9. The motor cooling method according to claim 8, characterized in that: Determining the flow rate and pressure of the cooling oil according to the operating temperature includes: Obtaining a corresponding relationship table of operating temperature, cooling oil flow rate and cooling oil pressure; The flow rate and pressure of the cooling oil are determined according to the corresponding relationship table and the operating temperature.

10. A computer-readable storage medium having a computer program or instruction stored thereon, characterized in that: When the computer program or instruction is executed, the motor cooling method according to claim 8 or 9 is implemented.

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