Method for determining initial refueling amount of electrically-driven oil-cooled motor, electronic equipment and storage medium

Abstract

The invention discloses a method for determining the initial refueling amount of an electrically-driven oil-cooled motor, electronic equipment and a storage medium, and belongs to the field of oil-cooled motor design. The method comprises the steps that according to a geometric model of the oil-cooled motor, a fluid model of the oil quantity of the oil-cooled motor is built through simulation software, and oil quantity parameters of the oil-cooled motor under different working conditions are calculated; according to the oil quantity parameters, the extreme value of the oil adding amount of the oil cooling motor under the multiple working conditions is calculated; and according to the extreme value of the oil-cooling motor oil filling amount, the oil-cooling motor initial oil filling amount range capable of meeting all working conditions is determined. According to the method, different working conditions and different unknown oil quantity parameters of the oil-cooled motor are comprehensively considered, the range of the oil filling quantity is obtained in advance through software simulation, it can be guaranteed that an oil pump does not suck air, oil does not submerge an air gap, the accuracy rate of the finally determined oil filling quantity is high, and time and cost are saved.

Description

Technical Field

[0001] The present invention belongs to the field of oil-cooled motor design, and in particular relates to a method for determining an initial oil filling amount of an electric-driven oil-cooled motor, an electronic device, and a storage medium. Background Art

[0002] Oil-cooled electric drive systems use oil as a cooling medium. They are primarily used to cool components such as motors and controllers in new energy vehicles. Excessive oil intake can increase oil temperature, impacting system performance and increasing maintenance costs. Excessive oil intake can lead to insufficient lubrication of gears and bearings, increasing mechanical wear, shortening component life, and inadequate cooling. Therefore, accurate oil intake is crucial to ensure the system meets cooling requirements. Therefore, the required oil intake for system cooling must be pre-calculated during vehicle development.

[0003] During operation, oil-cooled motors must ensure the oil pump operates normally without cavitation to meet the heat dissipation requirements of the motor's internal oil. If the oil pump experiences cavitation risk, air will be drawn in, causing increased pump noise. Furthermore, the drawn-in oil will contain air bubbles, which will enter the pipeline along with the oil, reducing oil flow and affecting heat dissipation. This can also cause the oil pump to overheat, wear internal seals, and lead to unstable system operation, reduced efficiency, and shortened pump life.

[0004] It's also important to ensure that the oil in the oil pan does not cover the air gap during normal motor operation. This can increase rotor drag losses, raise motor temperatures, and even severely demagnetize the permanent magnets. Therefore, it's important to determine the initial oil level in oil-cooled motors in advance to ensure proper operation.

[0005] The conventional method for determining the initial refueling volume is to place the oil-cooled electric drive system prototype on a test bench for testing, and determine the initial refueling volume by continuously changing the test conditions. This method cannot take into account all operating conditions, is costly and time-consuming, and it is difficult to obtain the optimal initial refueling volume range. Summary of the Invention

[0006] The technical problem to be solved by the present invention is how to more efficiently determine the initial refueling amount range of the oil-cooled motor to ensure that the oil pump of the oil-cooled motor does not suck empty and the oil does not cover the air gap.

[0007] To achieve the above object, the technical solution of the present invention is:

[0008] In a first aspect, a method for determining an initial oil filling amount for an electric-driven oil-cooled motor comprises the following steps:

[0009] Obtaining a geometric model of the oil-cooled motor, constructing a fluid model of the oil volume of the oil-cooled motor using simulation software based on the geometric model of the oil-cooled motor, and calculating oil volume parameters of the oil-cooled motor under different operating conditions based on the fluid model of the oil volume of the oil-cooled motor;

[0010] Based on the oil quantity parameters, calculate the extreme values of oil quantity for the oil-cooled motor under various working conditions;

[0011] Based on the extreme value of the oil-cooled motor's oil filling amount, determine the initial oil filling amount range of the oil-cooled motor that can meet all working conditions.

[0012] The oil quantity parameters include:

[0013] The first oil quantity parameter is the total oil quantity when the oil-cooled motor is full of oil;

[0014] The second oil quantity parameter is the larger value of the stator oil spraying amount, rotor oil throwing amount, and shaft oil storage amount inside the motor at the lowest speed of the oil-cooled motor, and the stator oil spraying amount, rotor oil throwing amount, and shaft oil storage amount inside the motor at the highest speed;

[0015] The third oil quantity parameter is the amount of oil applied to the internal parts of the oil-cooled motor;

[0016] The fourth oil quantity parameter is the minimum amount of oil remaining in the oil pan when the oil pump is not empty and the motor is not tilted;

[0017] The fifth oil quantity parameter is the minimum amount of oil remaining in the oil pan when the oil pump is not sucking out and the motor is tilted at the maximum angle;

[0018] The sixth oil quantity parameter is the maximum remaining oil volume in the oil pan when the oil does not flood the air gap and the motor is not tilted;

[0019] The seventh oil quantity parameter is the maximum amount of oil remaining in the oil pan when the oil does not submerge the air gap and the motor is tilted at the maximum angle;

[0020] The eighth oil quantity parameter is the remaining oil quantity in the oil pan when the electronic pump runs at the lowest speed and the oil does not submerge the air gap.

[0021] The extreme values of the refueling amount include: the minimum refueling amount in the non-tilted state, the maximum refueling amount in the non-tilted state, the minimum refueling amount in the tilted state, the maximum refueling amount in the non-tilted state, and the maximum refueling amount at the lowest speed of the electronic pump. The calculation formula is:

[0022]

[0023] In the above formula, V1 is the first oil quantity parameter, V2 is the second oil quantity parameter, V3 is the third oil quantity parameter, V4 is the fourth oil quantity parameter, V4' is the fifth oil quantity parameter, V5 is the sixth oil quantity parameter, V5' is the seventh oil quantity parameter, V6 is the eighth oil quantity parameter, V0min is the minimum oil quantity in the non-tilted state, V0max is the maximum oil quantity in the non-tilted state, Vqmin is the minimum oil quantity in the tilted state, Vqmax is the maximum oil quantity in the non-tilted state, and Vpmax is the maximum oil quantity of the electronic pump at the lowest speed.

[0024] The maximum value of the minimum refueling amount in the non-tilted state and the minimum refueling amount in the tilted state is determined as the minimum refueling amount; the minimum value of the maximum refueling amount in the non-tilted state, the maximum refueling amount in the tilted state and the maximum refueling amount of the electronic pump at the lowest speed is determined as the maximum refueling amount.

[0025] The initial oil filling amount range of the oil-cooled motor is [Vmin, Vmax], where Vmin is the minimum oil filling amount and Vmax is the maximum oil filling amount.

[0026] The method for calculating the oil quantity parameter is smoothed particle hydrodynamics method.

[0027] In a second aspect, an electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned method when executing the program.

[0028] In a third aspect, a computer-readable storage medium stores a computer program, which implements the above method when executed by a processor.

[0029] This invention utilizes particle-based fluid dynamics simulation software for numerical analysis and data structuring to analyze and solve computational methods involving fluid flow problems. This method can simulate the complex fluid flow conditions within oil-cooled motors without physical risk, allowing for more accurate determination of oil flow parameters such as oil dripping and oil rejection. This invention comprehensively considers the diverse operating conditions and unknown oil flow parameters of oil-cooled motors, using software simulation to pre-determine the range of oil flow rates. This ensures that the oil pump does not drain and that the oil does not flood air gaps. The final determined oil flow rate is highly accurate, saving time and costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Flowchart of the method for determining the initial oil filling amount for oil-cooled motors. DETAILED DESCRIPTION

[0031] In order to elaborate on the technical solutions adopted by the present invention to achieve the predetermined technical objectives, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments, and the technical means or technical features in the embodiments of the present invention can be replaced without creative work. The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0032] Example 1

[0033] A method for determining the initial oil filling amount of an oil-cooled motor comprises the following steps:

[0034] Step 1: Obtain a geometric model of the oil-cooled motor, construct a fluid model of the oil volume of the oil-cooled motor using simulation software based on the geometric model of the oil-cooled motor, and calculate the oil volume parameters of the oil-cooled motor under different operating conditions based on the fluid model of the oil volume of the oil-cooled motor;

[0035] Oil quantity parameters for oil-cooled motors include:

[0036] When the motor is in normal operation, the total oil volume V1 when the oil-cooled motor is full of oil. The total oil volume includes the oil volume in the coarse filter, electronic pump, fine filter, oil cooler, stator oil circuit, etc.

[0037] The larger value V2 of the stator oil spraying amount, rotor oil throwing amount and shaft oil storage amount when the oil-cooled motor is running at the lowest speed and the stator oil spraying amount, rotor oil throwing amount and shaft oil storage amount when the motor is running at the highest speed;

[0038] When the motor is operating normally, the amount of oil on the internal parts of the oil-cooled motor is V3, including the amount of oil on the motor inner wall, winding ends, rotor end plates, bearings, and other inner and outer surfaces where oil can be poured;

[0039] When the motor is operating normally and the oil pump is not empty, and the motor is not tilted, the minimum remaining oil volume in the oil pan is V4; when the motor is tilted at the maximum angle, the minimum remaining oil volume in the oil pan is V4';

[0040] When the motor is operating normally and the oil does not flood the air gap, and the motor is not tilted, the maximum remaining oil volume in the oil pan is V5. When the motor is tilted at the maximum angle, the maximum remaining oil volume in the oil pan is V5';

[0041] The maximum tilt angle of the motor mainly depends on the design and application scenario of the motor. For different types of motors, the limits on the tilt angle are different, and the present invention does not impose any restrictions here.

[0042] In some embodiments, the tilt angles corresponding to the oil-cooled motor system can include five operating conditions: no tilt, uphill tilt, downhill tilt, left tilt, and right tilt. By considering the extreme tilt angles under various operating conditions, the obtained results can be applied to most situations, making the results more accurate.

[0043] When the electronic pump is running at the lowest speed, the stator oil channel filling amount, that is, the remaining oil amount in the oil pan at which the oil does not submerge the air gap, is V6.

[0044] In the embodiments of this application, a geometric model refers to a mathematical representation of shapes and structures used in computer-aided design and computer graphics. A geometric model describes the shape, size, and positional relationships of objects through mathematical equations or parameters, allowing these objects to be accurately represented and manipulated in a computer. In the design of an oil-cooled motor system, it is typically necessary to first construct a geometric model of the system to facilitate performance analysis, thermal management design, and structural optimization.

[0045] The simulation software calculates various oil flow parameters using smoothed particle hydrodynamics (SPH), hereafter referred to as the particle method. The particle method software assists in calculating the amount of oil dripping and oil dumping during motor operation. The particle method is a fluid simulation method based on the Lagrangian system (which studies moving fluid particles and focuses on the temporal variation of their parameters).

[0046] The particle method divides the fluid into a certain number of micro-particles, and by establishing the control equation, solves the interaction between each particle within the range of action, and then obtains the motion law of the fluid.

[0047] In the particle method, the interaction between particles is calculated using the kernel function, and the calculation formula is:

[0048]

[0049] Where r represents the distance between particles, It represents the range of interaction between individual particles. The sum of all interactions within the range of a single particle is calculated using the particle number density. The calculation formula is:

[0050]

[0051] The simulation software used in this embodiment is a fluid mechanics simulation software based on the particle method, which can perform structural analysis, thermal analysis, and fluid dynamics analysis on complex mathematical models. It can simulate the mechanical behavior, thermal behavior, and fluid flow problems of the oil inside the oil-cooled motor under different working conditions, and predict the oil quantity parameters at various positions of the motor under different working conditions.

[0052] Step 2: Based on the motor's oil quantity parameters, calculate the extreme values of the oil-cooled motor's oil quantity under various working conditions;

[0053] Including: the minimum refueling amount V0min and the maximum refueling amount V0max in the non-tilted state, the minimum refueling amount Vqmin and the maximum refueling amount Vqmax in the tilted state, and the maximum refueling amount Vpmax of the electronic pump at the lowest speed; the calculation formula is as follows:

[0054] .

[0055] Step 3: Based on the extreme value of the oil-cooled motor oil filling amount, determine the initial oil-cooled motor oil filling amount range that can meet all working conditions.

[0056] The initial refueling amount range of the motor is [Vmin, Vmax], where the minimum refueling amount Vmin is the maximum value of the minimum refueling amount V0min in the non-tilted state and the minimum refueling amount Vqmin in the tilted state, and the maximum refueling amount Vmax is the minimum value of the maximum refueling amount V0max in the non-tilted state, the maximum refueling amount Vqmax in the tilted state and the maximum refueling amount Vpmax of the electronic pump at the lowest speed.

[0057] In some embodiments, the oil quantity parameters of the oil-cooled motor under different operating conditions are shown in the following table:

[0058]

[0059] Through calculation, we get: in the non-tilted state, the minimum refueling volume V0min = 1.859L, and the maximum refueling volume V0max = 2.634L; in the tilted state, the minimum refueling volume Vqmin = 1.904L, and the maximum refueling volume Vqmax = 2.604L; the maximum refueling volume Vpmax = 2.533L at the lowest speed of the electronic pump.

[0060] In summary, it can be concluded that under the tilting working condition of the motor and the lowest speed state of the electronic pump when the motor is just starting, the range of the initial refueling volume is determined to be Vqmin-Vpmax to ensure that the oil pump does not suck air and the oil does not flood the air gap.

[0061] This invention utilizes particle-based fluid dynamics simulation software for numerical analysis and data structuring to analyze and solve computational methods involving fluid flow problems. This method can simulate the complex fluid flow conditions within oil-cooled motors without physical risk, allowing for more accurate determination of oil flow parameters such as oil dripping and oil rejection. This invention comprehensively considers the diverse operating conditions and unknown oil flow parameters of oil-cooled motors, using software simulation to pre-determine the range of oil flow rates. This ensures that the oil pump does not drain and that the oil does not flood air gaps. The final determined oil flow rate is highly accurate, saving time and costs.

[0062] Example 2

[0063] An embodiment of the present application also provides an electronic device, including a processor, a memory, and a computer program stored in the memory and capable of running on the processor. The program is executed by the processor to implement the various processes of the above-mentioned embodiment of the method for determining the initial refueling amount of an oil-cooled motor.

[0064] Example 3

[0065] An embodiment of the present application also provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the various processes of the above-mentioned embodiment of the method for determining the initial refueling amount of an oil-cooled motor and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0066] The computer-readable storage medium may be a computer read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0067] Example 4

[0068] An embodiment of the present application also provides a computer program product, including a computer program, which is executed by a processor to implement the above-mentioned method for determining the initial refueling amount of the oil-cooled motor.

[0069] Example 5

[0070] An embodiment of the present application further provides a chip, which includes a processor and a communication interface, which is coupled to the processor. The processor is used to run programs or instructions to implement the various processes of the above-mentioned embodiment of the method for determining the initial refueling amount of an oil-cooled motor, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0071] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for determining the initial oil filling amount of an electric drive oil-cooled motor, characterized in that: The steps include: Obtaining a geometric model of the oil-cooled motor, constructing a fluid model of the oil volume of the oil-cooled motor using simulation software based on the geometric model of the oil-cooled motor, and calculating oil volume parameters of the oil-cooled motor under different operating conditions based on the fluid model of the oil volume of the oil-cooled motor; Based on the oil quantity parameters, calculate the extreme values of oil quantity for the oil-cooled motor under various working conditions; Based on the extreme value of the oil-cooled motor's oil filling amount, determine the initial oil filling amount range of the oil-cooled motor that can meet all working conditions.

2. The method for determining the initial oil filling amount of an electric drive oil-cooled motor according to claim 1, characterized in that: The oil quantity parameters include: The first oil quantity parameter is the total oil quantity when the oil-cooled motor is full of oil; The second oil quantity parameter is the larger value of the stator oil spraying amount, rotor oil throwing amount, and shaft oil storage amount inside the motor at the lowest speed of the oil-cooled motor, and the stator oil spraying amount, rotor oil throwing amount, and shaft oil storage amount inside the motor at the highest speed; The third oil quantity parameter is the amount of oil applied to the internal parts of the oil-cooled motor; The fourth oil quantity parameter is the minimum amount of oil remaining in the oil pan when the oil pump is not empty and the motor is not tilted; The fifth oil quantity parameter is the minimum amount of oil remaining in the oil pan when the oil pump is not sucking out and the motor is tilted at the maximum angle; The sixth oil quantity parameter is the maximum remaining oil volume in the oil pan when the oil does not flood the air gap and the motor is not tilted; The seventh oil quantity parameter is the maximum amount of oil remaining in the oil pan when the oil does not submerge the air gap and the motor is tilted at the maximum angle; The eighth oil quantity parameter is the remaining oil quantity in the oil pan when the electronic pump runs at the lowest speed and the oil does not submerge the air gap.

3. The method for determining the initial oil filling amount of an electric drive oil-cooled motor according to claim 2, characterized in that: The extreme values of the refueling amount include: the minimum refueling amount in the non-tilted state, the maximum refueling amount in the non-tilted state, the minimum refueling amount in the tilted state, the maximum refueling amount in the non-tilted state, and the maximum refueling amount at the lowest speed of the electronic pump. The calculation formula is: In the above formula, V1 is the first oil quantity parameter, V2 is the second oil quantity parameter, V3 is the third oil quantity parameter, V4 is the fourth oil quantity parameter, V4' is the fifth oil quantity parameter, V5 is the sixth oil quantity parameter, V5' is the seventh oil quantity parameter, V6 is the eighth oil quantity parameter, V0min is the minimum oil quantity in the non-tilted state, V0max is the maximum oil quantity in the non-tilted state, Vqmin is the minimum oil quantity in the tilted state, Vqmax is the maximum oil quantity in the non-tilted state, and Vpmax is the maximum oil quantity of the electronic pump at the lowest speed.

4. The method for determining the initial oil filling amount of an electric drive oil-cooled motor according to claim 3, characterized in that: The maximum value of the minimum refueling amount in the non-tilted state and the minimum refueling amount in the tilted state is determined as the minimum refueling amount; the minimum value of the maximum refueling amount in the non-tilted state, the maximum refueling amount in the tilted state and the maximum refueling amount of the electronic pump at the lowest speed is determined as the maximum refueling amount.

5. The method for determining the initial oil filling amount of an electric drive oil-cooled motor according to claim 4, characterized in that: The initial oil filling amount range of the oil-cooled motor is [Vmin, Vmax], where Vmin is the minimum oil filling amount and Vmax is the maximum oil filling amount.

6. The method for determining the initial oil filling amount of an electric drive oil-cooled motor according to claim 1, characterized in that: The method for calculating the oil quantity parameter is smoothed particle hydrodynamics method.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the method according to any one of claims 1 to 6 is implemented.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

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