Control method and system of oil-cooled motor cooling system, vehicle and storage medium

Abstract

The application discloses an oil-cooled motor cooling system control method, system, vehicle and storage medium, comprising: in response to identifying that the motor working condition is a motor overheating risk working condition, issuing an oil pump maximum flow request, and controlling the oil pump to supply cooling oil according to the oil pump maximum flow request; in response to identifying that the motor working condition is a motor risk-free working condition, issuing an oil pump basic flow request, and controlling the oil pump to supply cooling oil according to the oil pump basic flow request; in response to identifying that the motor working condition is a motor ordinary working condition, constructing a cooling system total loss function, determining an optimal cooling flow according to the cooling system total loss function, issuing an optimal cooling flow request, and controlling the oil pump to supply cooling oil according to the optimal cooling flow request. The application can intelligently identify the overheating risk working condition of the motor and request the maximum cooling flow to protect the motor, while comprehensively considering the oil pump energy consumption expenditure and the oil-cooled motor efficiency benefit in the cooling process under different working conditions, so that the energy consumption of the system is minimized.

Description

Technical Field

[0001] This invention relates to the field of motor technology, specifically to a control method, system, vehicle, and storage medium for an oil-cooled motor cooling system. Background Technology

[0002] As the primary power source for new energy vehicles, the electric motor's performance directly impacts the vehicle's power and fuel economy. The development of powertrains towards higher power, higher integration, and higher speeds presents new challenges for motor cooling. Motor temperature directly affects motor performance; furthermore, overheating can even lead to electrical insulation failures and permanent magnet demagnetization, causing motor malfunction and ultimately threatening vehicle safety.

[0003] Currently, the main cooling methods for automotive motors are water cooling and oil cooling. Water cooling is an indirect cooling method, which has lower cooling efficiency and poses a risk to the sealing of the water channels. Oil cooling is a direct cooling method, using an oil pump to introduce cooling oil into the cooling circuit. On one hand, the cooling oil is sprayed onto the external end windings through a spray assembly, and on the other hand, the rotor rotation throws the cooling oil in the rotor oil circuit into the interior of the end windings for cooling. High-performance motors typically use flat wire windings, which facilitates the penetration of cooling oil into the gaps between the flat wire windings to improve cooling performance. Therefore, the combination of flat wire windings and oil cooling technology has attracted industry attention.

[0004] For example, patent document CN 111799950 A discloses a new energy vehicle, a drive motor oil cooling system, and a control method. The drive motor oil cooling system includes a front cover and a base. The front cover has an oil inlet and an oil outlet. The internal circulation space includes a temperature measuring element for detecting the stator and winding temperatures, a speed measuring device for detecting the drive motor speed, at least two guide pipes for guiding cooling oil to the components to be cooled, a regulating device for adjusting the flow rate of cooling oil entering the guide pipes, and a controller. The drive motor oil cooling system provided by this method can determine different operating conditions of the motor based on temperature and speed data, and rationally allocate the flow rate of cooling oil through different guide pipes according to the actual situation of different operating conditions. This enables optimal oil quantity control under optimal cooling effect, reducing energy consumption, and simultaneously targeting different parts of the motor for targeted cooling, thus improving the cooling effect. However, this method has the following problems: First, it does not address the critical motor overheating condition and lacks corresponding over-temperature protection measures. Second, the energy benefits of motor cooling and the energy expenditure of the oil pump in the oil cooling system are in competition, and this method does not consider the overall energy benefits gained by the motor due to cooling. During motor operation, increasing the cooling flow rate can lower the motor temperature, thereby improving motor efficiency (i.e., reducing motor energy consumption); however, increasing the cooling flow rate will lead to increased energy consumption of the low-pressure oil pump. Furthermore, controlling the oil pump speed solely based on the motor temperature collected by a temperature sensor is prone to cooling lag, which may cause the motor to overheat under heavy load conditions.

[0005] For example, patent document CN 113612351 A discloses a cooling structure and method for a drive motor, an oil-cooled motor, and an automobile. This is applicable to cooling the stator of new energy vehicles. The drive motor includes a housing, which encloses an inner cavity to house the stator core and an oil injection ring. Cooling oil passages are provided within the area enclosed by the oil injection ring, housing, and stator core, allowing coolant to flow through the stator core and oil injection ring, at least cooling the stator core. The document also describes a method for cooling the drive motor, an oil-cooled motor, and an automobile, designed with the cooling structure as a unit. This method focuses on cooling the stator core. However, it does not address the identification of motor overheating conditions or overheat protection cooling methods, posing a risk of motor overheating. Furthermore, this method does not consider the overall energy consumption of the motor cooling system, which is detrimental to vehicle energy conservation and emission reduction.

[0006] Therefore, it is necessary to develop a control method, storage medium, equipment, and vehicle for an oil-cooled motor cooling system. Summary of the Invention

[0007] The purpose of this invention is to provide a control method, system, vehicle, and storage medium for an oil-cooled motor cooling system. This system can intelligently identify the motor's overheating risk conditions and request the maximum cooling flow to protect the motor. At the same time, it comprehensively considers the oil pump energy consumption and oil-cooled motor efficiency gains during the cooling process under different operating conditions to achieve the lowest possible energy consumption of the cooling system.

[0008] In a first aspect, the control method for an oil-cooled motor cooling system according to the present invention includes the following steps:

[0009] Identify motor operating conditions;

[0010] When the motor operating condition is identified as a risky condition for motor overheating, a request for maximum oil pump flow is issued, and the oil pump is controlled to supply cooling oil according to the request for maximum oil pump flow.

[0011] When the motor operating condition is identified as a risk-free operating condition, a basic flow request for the oil pump is issued, and the oil pump is controlled to supply cooling oil according to the basic flow request.

[0012] When the motor operating condition is identified as normal, the total cooling system loss function is constructed, the optimal cooling flow rate is determined based on the total cooling system loss function, and an optimal cooling flow rate request is issued. Based on the optimal cooling flow rate request, the oil pump is controlled to supply cooling oil.

[0013] Optionally, the cooling oil temperature and motor temperature can be obtained;

[0014] When it is determined that the cooling oil temperature is greater than the oil temperature limit, the motor operating condition is considered to be a motor overheating risk condition;

[0015] Alternatively, if it is determined that the cooling oil temperature is less than or equal to the oil temperature limit and the motor temperature is greater than the motor temperature limit, the motor operating condition is considered to be a motor overheating risk condition.

[0016] Optionally, the cooling oil temperature and motor temperature can be obtained;

[0017] When it is determined that the cooling oil temperature is less than or equal to the oil temperature limit, the motor temperature is less than or equal to the motor temperature limit, and the motor temperature is less than or equal to the motor risk-free temperature, the motor operating condition is considered to be the motor risk-free operating condition; wherein, the motor temperature limit is greater than the motor risk-free temperature.

[0018] Optionally, the cooling oil temperature and motor temperature can be obtained;

[0019] When the cooling oil temperature is less than or equal to the oil temperature limit, the motor temperature is less than or equal to the motor temperature limit, and the motor temperature is greater than the motor risk-free temperature, the motor operating condition is considered to be the normal operating condition of the motor.

[0020] Optionally, the total loss function of the cooling system can be constructed based on the motor power, motor efficiency function, and oil pump energy consumption function.

[0021] Optionally, the method for calculating the motor power is as follows:

[0022] Obtain the motor speed and motor torque, and calculate the motor power based on the motor speed and motor torque.

[0023] Optionally, the formula for calculating the motor power is:

[0024]

[0025] Among them, P motor T represents the motor power. tq n is the motor torque, and n is the motor speed.

[0026] Optionally, the energy consumption function of the oil pump is:

[0027] P oil =b1+b2f+b3f 2 ;

[0028] Where: P oil This is the power consumption of the oil pump; b1, b2, and b3 are all calibration parameters; f is the cooling flow rate, and the value range of f is: base flow rate < f < maximum flow rate.

[0029] Optionally, the motor efficiency function is:

[0030] η=a0+a1T cool ;

[0031] Where η is the motor efficiency; a0 and a1 are calibration parameters; T cool T represents the temperature after cooling at a cooling flow rate f. cool =T0-(c1+c2f+c3f) 2 ), where T0 is the motor temperature, and c1, c2, and c3 are calibration parameters.

[0032] Optionally, when the motor is in generator mode, the total loss function of the cooling system is:

[0033] P loss =P motor (1-η)+P oil ;

[0034] Among them, P loss This is the total loss of the oil-cooled motor cooling system.

[0035] Optionally, when the motor is in driving mode, the total loss function of the cooling system is:

[0036]

[0037] Among them, Ploss This is the total loss of the oil-cooled motor cooling system; η0 is T cool The motor efficiency obtained when T is equal to η0 is η0 = a0 + a1T0.

[0038] Optionally, the optimal cooling flow rate is determined based on the total loss function of the cooling system, specifically as follows:

[0039] Plot the curve of total cooling system loss as a function of cooling flow rate using the total cooling system loss function, i.e., P. loss Curve; within the range of cooling flow rates that the oil pump can provide, let P loss The cooling flow rate at the minimum value of the curve is the optimal cooling flow rate.

[0040] Secondly, the oil-cooled motor cooling system of the present invention includes a processor and a memory; wherein the memory stores a computer-readable program, and when the computer-readable program is invoked by the processor, it can execute the steps of the control method of the oil-cooled motor cooling system of the present invention.

[0041] Thirdly, the vehicle described in this invention employs the oil-cooled motor cooling system as described in this invention.

[0042] Fourthly, the present invention provides a storage medium storing a computer-readable program, which, when invoked, can execute the steps of the control method for the oil-cooled motor cooling system as described in the present invention.

[0043] This invention has the following advantages: The control method for the oil-cooled motor cooling system provided by this invention comprehensively considers the oil pump power and motor efficiency gains during the cooling process, achieving the lowest total energy consumption of the oil-cooled motor cooling system while avoiding the risk of motor overheating. This control method can intelligently identify motor overheating risk conditions, motor no-risk conditions, and normal motor conditions based on the cooling oil temperature and motor temperature. For motor overheating risk conditions, it requests the maximum cooling flow rate to protect the motor; for motor no-risk conditions, it requests the basic cooling flow rate to reduce system energy consumption; and for normal motor conditions, it constructs the total cooling system loss function using the motor power, motor efficiency function, and oil pump power function, and calculates the optimal cooling flow rate based on the total cooling system loss function, thus achieving the lowest possible energy consumption of the cooling system. Attached Figure Description

[0044] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 This is a flowchart of the present invention;

[0046] Figure 2 A flowchart illustrating a specific embodiment of the present invention;

[0047] Figure 3 This is a schematic diagram of the cooling circuit of the oil-cooled motor cooling system in this invention;

[0048] Figure 4 This is a schematic diagram of the motor cooling principle of the oil-cooled motor cooling system in this invention;

[0049] In the diagram: 1. Oil pan, 2. Oil pump, 3. Proportional valve, 4. Spray assembly, 5. Rotor internal oil passage, 6. Motor, 61. Motor stator core, 62. Electronic stator end winding, 63. Motor rotor, 7. Cooling oil passage. Detailed Implementation

[0050] The present invention will now be described in detail with reference to the accompanying drawings.

[0051] like Figure 1 As shown in this embodiment, a control method for an oil-cooled motor cooling system includes the following steps:

[0052] Identify motor operating conditions;

[0053] When the motor operating condition is identified as a risky condition for motor overheating, a request for maximum oil pump flow is issued, and the oil pump is controlled to supply cooling oil according to the request for maximum oil pump flow.

[0054] When the motor operating condition is identified as a risk-free operating condition, a basic flow request for the oil pump is issued, and the oil pump is controlled to supply cooling oil according to the basic flow request.

[0055] When the motor operating condition is identified as normal, the total cooling system loss function is constructed, the optimal cooling flow rate is determined based on the total cooling system loss function, and an optimal cooling flow rate request is issued. Based on the optimal cooling flow rate request, the oil pump is controlled to supply cooling oil.

[0056] In this embodiment, the cooling oil temperature and the motor temperature are obtained;

[0057] When it is determined that the cooling oil temperature is greater than the oil temperature limit, the motor operating condition is considered to be a motor overheating risk condition;

[0058] Alternatively, if it is determined that the cooling oil temperature is less than or equal to the oil temperature limit and the motor temperature is greater than the motor temperature limit, the motor operating condition is considered to be a motor overheating risk condition.

[0059] In this embodiment, the cooling oil temperature and the motor temperature are obtained;

[0060] When it is determined that the cooling oil temperature is less than or equal to the oil temperature limit, the motor temperature is less than or equal to the motor temperature limit, and the motor temperature is less than or equal to the motor risk-free temperature, the motor operating condition is considered to be the motor risk-free operating condition; wherein, the motor temperature limit is greater than the motor risk-free temperature.

[0061] In this embodiment, the cooling oil temperature and the motor temperature are obtained;

[0062] When the cooling oil temperature is less than or equal to the oil temperature limit, the motor temperature is less than or equal to the motor temperature limit, and the motor temperature is greater than the motor risk-free temperature, the motor operating condition is considered to be the normal operating condition of the motor.

[0063] In this embodiment, the total loss function of the cooling system is constructed based on the motor power, motor efficiency function, and oil pump energy consumption function.

[0064] In this embodiment, the method for calculating the motor power is as follows:

[0065] Obtain the motor speed and motor torque, and calculate the motor power based on the motor speed and motor torque.

[0066] In this embodiment, the formula for calculating the motor power is:

[0067]

[0068] Among them, P motor T represents the motor power. tq n is the motor torque, and n is the motor speed.

[0069] In this embodiment, the energy consumption function of the oil pump is:

[0070] P oil =b1+b2f+b3f 2 ;

[0071] Where: P oil b1 is the power consumption of the oil pump; b2 and b3 are calibration parameters (obtained by testing the oil pump unit, measuring the change of oil pump power with cooling oil flow rate, and fitting the data through least squares); f is the cooling flow rate, and the value range of f is: base flow rate < f < maximum flow rate.

[0072] In this embodiment, the motor efficiency function is:

[0073] η=a0+a1T cool ;

[0074] Where η is the motor efficiency; a0 and a1 are calibration parameters; T cool T represents the temperature after cooling at a cooling flow rate f. cool =T0-(c1+c2f+c3f) 2), where T0 is the motor temperature, and c1, c2, and c3 are calibration parameters (obtained by testing the cooling system, measuring the change of motor temperature with cooling oil flow, and fitting the data using least squares fitting). These parameters are obtained from experimental data using least squares fitting.

[0075] In this embodiment, when the motor is in generator mode, the total loss function of the cooling system is:

[0076] P loss =P motor (1-η)+P oil ;

[0077] Among them, P loss This is the total loss of the oil-cooled motor cooling system.

[0078] In this embodiment, when the motor is in driving mode, the total loss function of the cooling system is:

[0079]

[0080] Among them, P loss This is the total loss of the oil-cooled motor cooling system; η0 is T cool The motor efficiency obtained when T is equal to η0 is η0 = a0 + a1T0.

[0081] In this embodiment, the optimal cooling flow rate is determined based on the total loss function of the cooling system, specifically as follows:

[0082] Plot the curve of total cooling system loss as a function of cooling flow rate using the total cooling system loss function, i.e., P. loss Curve; within the range of cooling flow rates that the oil pump can provide, let P loss The cooling flow rate at the minimum value of the curve is the optimal cooling flow rate.

[0083] The control method for the oil-cooled motor cooling system provided in this paper comprehensively considers the oil pump power and motor efficiency gains during the cooling process, achieving the lowest total energy consumption of the oil-cooled motor cooling system while avoiding the risk of motor overheating. This control method can intelligently identify motor overheating risk conditions, motor no-risk conditions, and normal motor conditions based on the cooling oil temperature and motor temperature. For motor overheating risk conditions, it requests the maximum cooling flow rate to protect the motor; for motor no-risk conditions, it requests the basic cooling flow rate to reduce system energy consumption; and for normal motor conditions, it constructs the total cooling system loss function using the motor power, motor efficiency function, and oil pump power function, and calculates the optimal cooling flow rate based on the total cooling system loss function, thus achieving the lowest possible cooling system energy consumption.

[0084] It should be noted that, as Figure 3 and Figure 4As shown, the oil-cooled motor cooling system described in this embodiment should at least include an oil pan 1, an oil pump 2, a cooling oil passage 7, a proportional valve 3, a spray assembly 4, an internal rotor oil passage 5, and a motor 6 (the motor includes a stator core 61, a cooling stator end winding 62, and a rotor 63) forming a cooling oil circulation loop. The oil pump 2 is located inside the oil pan 1 and is connected to the proportional valve 3 via the cooling oil passage 7. The proportional valve 3 is connected to the spray assembly 4 and the internal rotor oil passage 5 via the cooling oil passage 7. The spray assembly 4 and the internal rotor oil passage 5 are connected to the motor 6 via the cooling oil passage 7. The cooling oil passage 7 is the channel and path for the cooling oil to flow in the cooling system, including coolant channels connecting various components and spray paths. The cooling oil circulation loop is equipped with a temperature measuring element for detecting the motor temperature, a temperature measuring element for detecting the cooling oil temperature inside the oil pan 1, and measuring devices for detecting the motor speed and torque. During operation, oil pump 2 introduces cooling oil from oil pan 1 into cooling oil circuit 7. The cooling oil then flows through proportional valve 3 to form two cooling oil circuits, which flow to spray assembly 4 and rotor internal oil circuit 5 respectively. Figure 2 As shown, the cooling oil is sprayed out through the spray assembly 4 and the rotor internal oil passage 5 to directly cool the stator end winding 62 and stator core 61. Finally, the cooling oil flows back into the oil pan 1 from the oil outlet at the bottom of the motor 6.

[0085] The following combination Figure 2 A detailed explanation of the control method for oil-cooled motor cooling systems is provided:

[0086] A control method for an oil-cooled motor cooling system includes the following steps:

[0087] Step S1: Obtain the current temperature of the cooling oil through the cooling oil temperature sensor installed in the oil pan, and obtain the current temperature of the motor through the motor temperature sensor;

[0088] Step S2: Determine whether the cooling oil temperature is greater than the oil temperature limit. If so, it is considered to be a motor overheating risk condition and a request for maximum oil pump flow is issued, and proceed to step S8; otherwise, proceed to step S3.

[0089] Step S3: Determine whether the motor temperature is greater than the motor temperature limit. If so, it is considered to be a motor overheating risk condition and a request for maximum oil pump flow is issued, and proceed to step S8; otherwise, proceed to step S4.

[0090] Motor overheating conditions can be determined by the temperature of the cooling oil and the motor. When the motor temperature exceeds the motor temperature limit, it indicates that the motor is generating too much heat; when the cooling oil temperature exceeds the oil temperature limit, the cooling oil's heat dissipation capacity decreases. Both excessive heat generation and decreased heat dissipation capacity can lead to motor overheating. Therefore, steps S2 and S3 are considered to be motor overheating risk conditions, and the maximum flow rate of the oil pump should be requested.

[0091] Step S4: Determine whether the motor temperature is less than or equal to the motor's risk-free temperature. If so, it is considered a risk-free operating condition for the motor and an oil pump basic flow request is issued. Proceed to step S8. Otherwise, it is considered a normal operating condition for the motor and proceed to step S5.

[0092] To cope with sudden changes in motor operating conditions, the cooling oil circuit 7 should always be filled with cooling oil, and a base flow rate should be set for the oil-cooled motor cooling system. Furthermore, maintaining the base flow rate helps to keep the motor rotor lubricated; therefore, the base flow rate should be requested even under risk-free motor operating conditions.

[0093] Step S5: Obtain the motor speed through the motor speed sensor, obtain the motor torque using the phase current sensor combined with calibration data, and calculate the motor power based on the motor speed and motor torque.

[0094] In step S5, the motor speed sensor, i.e., the rotary transformer, is used to obtain the motor's speed information. The motor's torque information can be obtained by combining the phase current sensor with the motor bench calibration data. The motor bench calibration test uses a dynamometer to measure the motor's efficiency and torque at different speeds and currents, and outputs the corresponding efficiency and torque data to form the motor bench calibration data.

[0095] Step S6: Construct the total loss function of the cooling system based on the motor power, motor efficiency function, and oil pump energy consumption function;

[0096] Step S7: Determine the optimal cooling flow rate based on the total cooling system loss function and issue an optimal cooling flow rate request;

[0097] Step S8: Control the oil pump to supply cooling oil according to the flow request described in steps S2, S3, S4 and S7, and the process ends.

[0098] In this embodiment, an oil-cooled motor cooling system includes a processor and a memory; wherein, the memory stores a computer-readable program, and when the computer-readable program is invoked by the processor, it can execute the steps of the control method of the oil-cooled motor cooling system as described in this embodiment.

[0099] In this embodiment, a vehicle employs an oil-cooled motor cooling system as described in this embodiment.

[0100] In this embodiment, a storage medium stores a computer-readable program, which, when invoked, can execute the steps of the control method for the oil-cooled motor cooling system as described in this embodiment.

[0101] It should be noted that the storage medium shown in this embodiment can be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, the computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, carrying a computer-readable computer program. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media can also be any computer-readable medium other than computer-readable storage media, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.

[0102] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A control method for an oil-cooled motor cooling system, characterized in that, Includes the following steps: Identify motor operating conditions; When the motor operating condition is identified as a risky condition for motor overheating, a request for maximum oil pump flow is issued, and the oil pump is controlled to supply cooling oil according to the request for maximum oil pump flow. When the motor operating condition is identified as a risk-free operating condition, a basic flow request for the oil pump is issued, and the oil pump is controlled to supply cooling oil according to the basic flow request. When the motor operating condition is identified as normal motor operating condition, the total loss function of the cooling system is constructed, the optimal cooling flow rate is determined based on the total loss function of the cooling system, and an optimal cooling flow rate request is issued. Based on the optimal cooling flow rate request, the oil pump is controlled to supply cooling oil. The cooling oil temperature and motor temperature are obtained. When the cooling oil temperature is less than or equal to the oil temperature limit, the motor temperature is less than or equal to the motor temperature limit, and the motor temperature is greater than the motor risk-free temperature, the motor operating condition is considered to be the normal operating condition of the motor. Construct the total loss function of the cooling system based on the motor power, motor efficiency function, and oil pump energy consumption function; The energy consumption function of the oil pump is: P oil =b1+b2f+b3f 2 Where: P oil is the energy consumption power of the oil pump; b1, b2, and b3 are all calibration parameters; f is the cooling flow rate, and the value range of f is: base flow rate < f < maximum flow rate.

2. The control method for the oil-cooled motor cooling system according to claim 1, characterized in that: Obtain the cooling oil temperature and motor temperature; When it is determined that the cooling oil temperature is greater than the oil temperature limit, the motor operating condition is considered to be a motor overheating risk condition; Alternatively, if it is determined that the cooling oil temperature is less than or equal to the oil temperature limit and the motor temperature is greater than the motor temperature limit, the motor operating condition is considered to be a motor overheating risk condition.

3. The control method for the oil-cooled motor cooling system according to claim 1, characterized in that: Obtain the cooling oil temperature and motor temperature; When it is determined that the cooling oil temperature is less than or equal to the oil temperature limit, the motor temperature is less than or equal to the motor temperature limit, and the motor temperature is less than or equal to the motor risk-free temperature, the motor operating condition is considered to be the motor risk-free operating condition; wherein, the motor temperature limit is greater than the motor risk-free temperature.

4. The control method for the oil-cooled motor cooling system according to claim 1, characterized in that: The method for calculating the motor power is as follows: Obtain the motor speed and motor torque, and calculate the motor power based on the motor speed and motor torque.

5. The control method for the oil-cooled motor cooling system according to claim 1, characterized in that: The formula for calculating the motor power is: Among them, P motor T represents the motor power. tq n is the motor torque, and n is the motor speed.

6. The control method for the oil-cooled motor cooling system according to claim 5, characterized in that: The motor efficiency function is: Where η is the motor efficiency; a0 and a1 are calibration parameters; T cool Temperature after cooling at a cooling flow rate f Where T0 is the motor temperature, and c1, c2, and c3 are calibration parameters.

7. The control method for the oil-cooled motor cooling system according to claim 6, characterized in that: When the motor is in generator mode, the total loss function of the cooling system is: in, This is the total loss of the oil-cooled motor cooling system.

8. The control method for the oil-cooled motor cooling system according to claim 6, characterized in that: When the motor is in driving mode, the total loss function of the cooling system is: in, This is the total loss of the oil-cooled motor cooling system; For T cool The motor efficiency obtained at time T0 is equal to... .

9. The control method for the oil-cooled motor cooling system according to claim 7 or 8, characterized in that: The optimal cooling flow rate is determined based on the total loss function of the cooling system, specifically as follows: Plot the curve of total cooling system loss as a function of cooling flow rate using the total cooling system loss function. Curve; within the range of cooling flow rates that the oil pump can provide, let The cooling flow rate at the minimum value of the curve is the optimal cooling flow rate.

10. An oil-cooled motor cooling system, characterized in that: It includes a processor and a memory; wherein the memory stores a computer-readable program, which, when invoked by the processor, can execute the steps of the control method for the oil-cooled motor cooling system as described in any one of claims 1 to 9.

11. A vehicle, characterized in that: The oil-cooled motor cooling system as described in claim 10 is adopted.

12. A storage medium, characterized in that: It contains a computer-readable program that, when invoked, can execute the steps of the control method for the oil-cooled motor cooling system as described in any one of claims 1 to 9.

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