Efficiency optimization method for electric motor in electric vehicle, and control apparatus and storage medium

Abstract

The present application relates to an efficiency optimization method for an electric motor in an electric vehicle, and a control apparatus and a storage medium. The vehicle comprises an electric motor, an oil-cooling loop and a water-cooling loop, wherein the oil-cooling loop is used for dissipating heat for the electric motor of the vehicle. The method comprises: acquiring an oil temperature in an oil-cooling loop of a vehicle, and torque information and rotation speed information; and if the oil temperature, the torque information and the rotation speed information meet a first preset condition, making the oil-cooling loop not exchange heat with a water-cooling loop. During the implementation of the technical solution of the present application, an oil temperature, torque information and rotation speed information are taken into comprehensive consideration, thereby achieving optimization and control over a heat dissipation system of an electric vehicle. By means of the technique, the heat exchange between an oil-cooling loop and a water-cooling loop can be accurately controlled, thereby effectively improving the efficiency of an electric motor. By means of such an intelligent thermal management policy, the technique can ensure that the electric vehicle remains in an optimal operation state under various driving conditions, while improving the energy utilization efficiency and prolonging the service life of the electric motor.

Description

Efficiency optimization method, control device and storage medium of motor in electric vehicle

[0001] This application claims priority to Chinese patent application 202311765097.0, filed on December 20, 2023, entitled “Efficiency optimization method, control device and storage medium for motors in electric vehicles”. The entire contents of the above Chinese patent application are incorporated into this application by reference. Technical Field

[0002] The present application relates to the field of automobile control, and specifically provides an efficiency optimization method, a control device, and a storage medium for a motor in an electric vehicle. Background Art

[0003] With the popularization of automobiles, people have higher and higher requirements for various performance of automobiles, especially the efficiency of motors.

[0004] In the existing technology, only the influence of oil temperature on the efficiency of the electric drive system is considered. This single-index control strategy cannot achieve the optimal effect in electric vehicle applications.

[0005] Accordingly, the art needs a new method for optimizing the efficiency of motors in electric vehicles to solve the above problems.

[0006] Summary of the Invention

[0007] In order to overcome the above-mentioned defects, the present application is proposed to provide a solution or at least partially solve the technical problem in the prior art that optimizing motor efficiency only by oil temperature is not accurate enough.

[0008] In a first aspect, the present application provides a method for optimizing the efficiency of a motor in an electric vehicle, wherein the vehicle includes a motor, an oil cooling circuit, and a water cooling circuit, wherein the oil cooling circuit is used to dissipate heat from the vehicle motor. The method includes: obtaining the oil temperature, torque information, and speed information in the oil cooling circuit of the vehicle; if the oil temperature, torque information, and speed information meet a first preset condition, then preventing heat exchange between the oil cooling circuit and the water cooling circuit.

[0009] In one technical solution of the efficiency optimization method of the motor in the above-mentioned electric vehicle, "if the oil temperature, torque information and speed information meet the first preset condition, the oil cooling circuit and the water cooling circuit will not generate heat exchange", including: obtaining a first oil temperature threshold, a first torque threshold and a first speed threshold; if the oil temperature is less than the first oil temperature threshold, the torque information is less than the first torque threshold, and the speed information is greater than the first speed threshold, then the oil cooling circuit and the water cooling circuit will not generate heat exchange.

[0010] In one technical solution of the method for optimizing the efficiency of the motor in the above-mentioned electric vehicle, the vehicle further includes a heat exchanger, wherein the oil cooling circuit and the water cooling circuit perform heat exchange through the heat exchanger; the heat exchanger includes a first solenoid valve, wherein the opening of the first solenoid valve controls the heat exchange efficiency between the oil cooling circuit and the water cooling circuit.

[0011] In a technical solution of the above-mentioned method for optimizing the efficiency of the motor in the electric vehicle, the method further includes: if the oil temperature, torque information and speed information meet a second preset condition, heat exchange is generated between the oil cooling circuit and the water cooling circuit, wherein the heat exchange is used to suppress the rate of increase of the oil temperature.

[0012] In one technical solution of the efficiency optimization method of the motor in the above-mentioned electric vehicle, a first oil temperature threshold, a second oil temperature threshold, a first torque threshold and a first speed threshold are obtained. "If the oil temperature, torque information and speed information meet the second preset condition, the oil cooling circuit and the water cooling circuit are heat exchanged", including: if the oil temperature is greater than or equal to the first oil temperature threshold and less than the second oil temperature threshold, the torque information is less than the first torque threshold, and the speed information is greater than the first speed threshold, the oil cooling circuit and the water cooling circuit are heat exchanged.

[0013] In a technical solution of the efficiency optimization method of the motor in the above-mentioned electric vehicle, "if the oil temperature is greater than or equal to the first oil temperature threshold and less than the second oil temperature threshold, the torque information is less than the first torque threshold, and the speed information is greater than the first speed threshold, then the oil cooling circuit and the water cooling circuit generate heat exchange", including: if the oil temperature is greater than or equal to the first oil temperature threshold and less than the second oil temperature threshold, the torque information is less than the first torque threshold, and the speed information is greater than the first speed threshold, then the opening of the first solenoid valve is controlled to reach a preset first opening.

[0014] In one technical solution of the above-mentioned method for optimizing the efficiency of the motor in the electric vehicle, the oil cooling circuit includes a second solenoid valve, a third solenoid valve and a fourth solenoid valve, wherein the second solenoid valve is used to conduct the oil cooling circuit to cool the bearings in the motor, the third solenoid valve is used to conduct the oil cooling circuit to cool the rotor in the motor, and the fourth solenoid valve is used to conduct the oil cooling circuit to cool the stator in the motor, wherein the second solenoid valve, the third solenoid valve and the fourth solenoid valve all adjust the degree of cooling of the corresponding components by controlling the opening of the solenoid valve.

[0015] In one technical solution of the method for optimizing the efficiency of the motor in the above-mentioned electric vehicle, the method further includes: determining whether the vehicle is in a static heating state; if the vehicle is in a static heating state, the executed control includes: the second solenoid valve is in a closed state, and the fourth solenoid valve is in an open state, so that heat exchange occurs between the oil cooling circuit and the water cooling circuit.

[0016] In a technical solution of the method for optimizing the efficiency of the motor in the above-mentioned electric vehicle, the method further includes: if the vehicle is in a boost charging state, the control executed includes: if the vehicle is in a boost charging state, the control executed includes: the second solenoid valve is in a closed state, and the third solenoid valve is in an open state, so that heat exchange occurs between the oil cooling circuit and the water cooling circuit.

[0017] In a second aspect, a control device is provided, which includes a processor and a storage device, wherein the storage device is suitable for storing multiple computer programs, and the computer programs are suitable for being loaded and run by the processor to execute the efficiency optimization method of the motor in the electric vehicle described in any one of the technical solutions of the above-mentioned technical solutions of the efficiency optimization method of the motor in the electric vehicle.

[0018] In a third aspect, a computer-readable storage medium is provided, in which a plurality of computer programs are stored. The computer programs are suitable for being loaded and run by a processor to execute the efficiency optimization method of the motor in the electric vehicle described in any one of the technical solutions of the efficiency optimization method of the motor in the electric vehicle.

[0019] The above one or more technical solutions of this application have at least one or more of the following beneficial effects:

[0020] In implementing the technical solution of this application, optimized control of the electric vehicle's cooling system is achieved by comprehensively considering oil temperature, torque, and speed information. This technology precisely controls the heat exchange between the oil and water cooling circuits, effectively improving motor efficiency. Through this intelligent thermal management strategy, this technology ensures that electric vehicles maintain optimal operating conditions under various driving conditions, while also improving energy efficiency and motor life. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The disclosure of this application will be more easily understood with reference to the accompanying drawings. Those skilled in the art will readily appreciate that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of this application. Furthermore, similar numbers in the figures represent similar components, where:

[0022] FIG1 is a schematic flow chart of main steps of a method for optimizing the efficiency of a motor in an electric vehicle according to one embodiment of the present application;

[0023] Figure 2 is a graph showing the relationship between speed and motor efficiency at different oil temperatures obtained experimentally;

[0024] Figure 3 is a graph showing the relationship between torque and motor efficiency at different oil temperatures obtained based on experiments;

[0025] FIG4 is a flow chart showing the main steps of a method for optimizing the efficiency of a motor in an electric vehicle according to one embodiment of the present application;

[0026] FIG5 is a flow chart of a method for optimizing the efficiency of a motor in an electric vehicle according to an embodiment of the present application. DETAILED DESCRIPTION

[0027] Some embodiments of the present application are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present application and are not intended to limit the scope of protection of the present application.

[0028] In the description of this application, "module" and "processor" may include hardware, software, or a combination of both. A module may include hardware circuitry, various suitable sensors, communication ports, and memory. It may also include software components, such as computer programs, or a combination of software and hardware. A processor may be a central processing unit, a microprocessor, an image processor, a digital signal processor, or any other suitable processor. A processor has data and / or signal processing capabilities. A processor may be implemented in software, hardware, or a combination of both. Non-transitory computer-readable storage media include any suitable medium capable of storing computer programs, such as magnetic disks, hard disks, optical disks, flash memory, read-only memory, random access memory, and the like. The term "A and / or B" refers to all possible combinations of A and B, such as only A, only B, or both A and B. The terms "at least one of A or B" or "at least one of A and B" have similar meanings to "A and / or B" and may include only A, only B, or both A and B. The singular forms "one" and "the" may also include the plural forms.

[0029] As used herein, directional terms such as "front," "front side," "front portion," "rear," "rear side," and "rear portion" are based on the fore-and-aft direction of the vehicle after the component is installed. "Longitudinal," "longitudinal," and "longitudinal section" as used herein are based on the fore-and-aft direction of the vehicle after the component is installed, while "transverse," "transverse," and "cross-section" refer to directions perpendicular to the longitudinal direction.

[0030] Referring to FIG. 1 , FIG. 1 is a flow chart illustrating the main steps of a method for optimizing the efficiency of a motor in an electric vehicle according to an embodiment of the present application. As shown in FIG. 1 , the method for optimizing the efficiency of a motor in an electric vehicle according to an embodiment of the present application mainly includes the following steps S10 to S30 .

[0031] Step S10: Obtaining the oil temperature, torque information, and speed information in the oil cooling circuit of the vehicle.

[0032] In this embodiment, the oil cooling circuit is used to dissipate heat for the automobile motor.

[0033] In one embodiment, the oil temperature in the oil cooling circuit is detected by a sensor. Preferably, in this embodiment, the sensor for detecting the oil temperature is installed at the oil outlet of the motor to monitor the temperature of the oil. In this embodiment, the acquisition of torque information is achieved by a motor control unit (ECU). The torque sensor or ECU estimates the torque generated by the motor by analyzing the current and voltage data of the motor. In this embodiment, the rotational speed of the electric vehicle is achieved by a rotational speed sensor, which is installed on the motor shaft or wheel. In electric vehicles, due to the lack of a traditional gearbox, the rotational speed of the motor is directly related to the wheel speed, and therefore can also indirectly reflect the vehicle speed. Therefore, in this embodiment, the rotational speed information is the current vehicle speed or rotational speed.

[0034] In this embodiment, the reason for obtaining oil temperature, torque information, and speed information is explained. The parameters of the motor and oil cooling circuit in electric vehicles constitute the main factors affecting the efficiency of the motor. In the prior art, only the effect of oil temperature on motor efficiency is considered. Specifically, when the oil temperature is low, the viscosity of the oil coolant increases. For example, in a certain test, the viscosity of a certain brand of oil coolant was 24.9mPa·s at a temperature of 40°C; at -40°C, the viscosity was 12030mPa·s, an increase of 3 orders of magnitude. Since the oil coolant in the oil cooler is in full contact with the internal components of the motor in this embodiment, when the oil temperature drops, the oil coolant has a higher viscosity, which will affect the efficiency of the mechanical structure in the motor, that is, the efficiency of the motor is reduced, thereby reducing the efficiency of the motor.

[0035] In this application, actual experiments conducted on oil temperatures mentioned in the prior art revealed that there is no fixed functional relationship between motor efficiency and oil temperature. Figures 2 and 3 show the experimental data. As shown in Figures 2 and 3, it can be seen that in some cases, the effect of different oil temperatures on motor efficiency does not always follow the trend shown in the prior art, that is, the lower the oil temperature, the lower the motor efficiency.

[0036] Experiments have shown that the functional relationship between oil temperature and motor efficiency changes with changes in the experimental environment. The above scenario demonstrates that motor efficiency is not solely influenced by oil temperature, but by other parameters. Using oil temperature alone as a parameter affecting motor efficiency is insufficient for effectively determining motor efficiency. Therefore, after extensive experimental and theoretical research, this embodiment utilizes oil temperature, torque information, and speed information as a combined basis for determination.

[0037] By using oil temperature, torque information and speed information, a more accurate judgment of the efficiency of the motor can be obtained, so that subsequent operations can be executed more accurately, thereby improving the efficiency of the motor and making the executed steps more effective.

[0038] Step S20 : ​​If the oil temperature, the torque information, and the speed information satisfy a first preset condition, heat exchange between the oil cooling circuit and the water cooling circuit is stopped.

[0039] In this embodiment, the automobile further includes a heat exchanger, wherein the oil cooling circuit and the water cooling circuit perform heat exchange through the heat exchanger.

[0040] In one embodiment, when the oil temperature, torque, and speed information meet a first pre-determined condition, the system intentionally prevents heat exchange between the oil-cooling circuit and the water-cooling circuit. In this embodiment, the heat exchanger comprises a series of pipes or channels that allow oil and water to flow through without mixing. This design allows heat to be transferred from a higher-temperature fluid to a lower-temperature fluid, and vice versa, without mixing the two fluids.

[0041] In this embodiment, the first preset condition is a pre-set condition, wherein the first preset condition takes into account the oil temperature, torque information, and speed information, thereby performing further restrictions.

[0042] In this embodiment, steps S201-S202 are specifically executed, as shown in FIG4 , as follows:

[0043] Step S201: Acquire a first oil temperature threshold, a first torque threshold, and a first speed threshold.

[0044] In this embodiment, the first oil temperature threshold, the first torque threshold and the first speed threshold are all preset thresholds obtained based on experiments. The first oil temperature threshold, the first torque threshold and the first speed threshold are used to judge the efficiency of the vehicle's current motor, thereby executing the next step.

[0045] In one embodiment, as shown in FIG2 and FIG3 , the corresponding threshold value is obtained after multiple experiments.

[0046] Specifically, when selecting lower and higher oil temperatures, experiments are conducted using the control variable method to obtain the relationship between another key parameter and motor efficiency at different oil temperatures. In this embodiment, Figure 2 shows the relationship between speed and motor efficiency at different oil temperatures, and Figure 3 shows the relationship between torque and motor efficiency at different oil temperatures. In this embodiment, the experimental data obtained from Figures 2 and 3 show that when a certain threshold is met, the impact of different oil temperatures on motor efficiency is negligible when below a certain speed threshold, but when above a certain speed threshold, the motor efficiency varies significantly under different oil temperatures. This speed threshold is the first speed threshold.

[0047] In this embodiment, it can be seen from FIG3 that different oil temperatures have a greater impact on the efficiency of the motor when they are below a certain torque threshold, but when they are above a certain torque threshold, the impact of different oil temperatures on the efficiency of the motor can be ignored. In this embodiment, the two curves in FIG2 and FIG3 correspond to an oil temperature of 25 degrees Celsius and an oil temperature of 50 degrees Celsius, respectively. In FIG2 and FIG3 , it is obvious that there are two lines with a large difference in the efficiency of the motor, and the oil temperature with a higher temperature always corresponds to the higher efficiency of the motor. In the part where there are two lines with almost no difference in the efficiency of the motor, the line corresponding to the part with a higher efficiency of the motor in FIG2 belongs to a lower oil temperature, i.e., an oil temperature of 25 degrees, and the line corresponding to the part with a lower efficiency of the motor belongs to a higher oil temperature, i.e., an oil temperature of 50 degrees.

[0048] Therefore, it can be seen from the experimental data in Figures 2 and 3 that in electric vehicles, there are differences from the conventional knowledge in the prior art and the art. In the conventional knowledge of the prior art and those skilled in the art, the lower the oil temperature, the lower the efficiency of the motor. However, this application proves that under certain circumstances, there will be situations where the motor efficiency is similar at different oil temperatures, and the lower the oil temperature, the higher the motor efficiency is relative to when the oil temperature is high. The certain circumstances here are the situations where a certain speed or a certain torque is satisfied as obtained through experiments in this application. Therefore, in general, using only oil temperature as a control condition to improve motor efficiency is too simple and cannot cover all scenarios. For the efficiency of the motor, using only oil temperature as the basis for the experiment will cause the control method to fail to achieve the expected effect.

[0049] Step S202: If the oil temperature is less than the first oil temperature threshold, the torque information is less than the first torque threshold, and the speed information is greater than the first speed threshold, heat exchange between the oil cooling circuit and the water cooling circuit is not performed.

[0050] In this embodiment, the system determines whether to allow heat exchange between the oil cooling circuit and the water cooling circuit based on specific threshold conditions. These thresholds include a first oil temperature threshold, a first torque threshold, and a first speed threshold, which together determine the current operating state of the electric drive system.

[0051] In one embodiment, when the oil temperature is less than a first oil temperature threshold, the torque information is less than a first torque threshold, and the speed information is greater than a first speed threshold, heat exchange between the oil cooling circuit and the water cooling circuit is disabled. In this embodiment, the first speed threshold corresponds to the speed information. If the speed information is the speed, the first speed threshold corresponds to the speed; if the speed information is the vehicle speed, the first speed threshold corresponds to the vehicle speed. In this embodiment, the speed and vehicle speed have a fixed correspondence; that is, in this embodiment, the speed and vehicle speed are expressed in the same language, which will not be further explained here.

[0052] In this embodiment, more precise control of the motor efficiency is achieved through three types of information, namely speed information, torque information, and oil temperature, thereby achieving a better control effect relative to the oil temperature. It can be seen from Figures 2 and 3 that, under certain conditions, the higher the oil temperature, the higher the efficiency of the corresponding motor. When this condition is not met, the oil temperature is not positively correlated with the efficiency of the motor. In this embodiment, the certain condition is that the torque information is less than the first torque threshold and the speed information is greater than the first speed threshold. When this condition is met, the oil temperature will show a positive correlation with the efficiency of the motor. When this condition is not met, simply increasing the oil temperature cannot achieve the technical effect of prompting the motor efficiency.

[0053] In this embodiment, when the torque information is less than a first torque threshold, the speed information is greater than a first speed threshold, and the oil temperature is detected to be low at that time, the oil temperature is raised through a control method. Specifically, when the oil temperature is less than the first oil temperature threshold, the torque information is less than the first torque threshold, and the speed information is greater than the first speed threshold, heat exchange between the oil cooling circuit and the water cooling circuit is stopped.

[0054] In this embodiment, there are many ways to avoid heat exchange, such as using a bypass heat exchanger, or using a solenoid valve device to prevent the oil circuit or the water circuit from entering the radiator. Preferably, in this embodiment, a first solenoid valve is used to prevent the oil circuit from passing through the radiator, as shown in Figure 5. In this embodiment, the opening of the first solenoid valve controls the heat exchange efficiency between the oil cooling circuit and the water cooling circuit. Compared with the bypass radiator, the first solenoid valve can selectively control the flow rate of the oil cooling liquid flowing through the heat exchanger in the oil cooling circuit by controlling the opening of the first solenoid valve, thereby further controlling the heat exchange rate between the oil cooling liquid in the oil cooling circuit and the water cooling liquid in the water cooling circuit. In this embodiment, the larger the opening of the first solenoid valve, the higher the heat exchange efficiency between the oil cooling circuit and the water cooling circuit.

[0055] In this step, if the oil temperature is less than a first oil temperature threshold, the torque information is less than a first torque threshold, and the speed information is greater than a first speed threshold, heat exchange between the oil cooling circuit and the water cooling circuit is not performed. This strategy is implemented to optimize the operating efficiency of the electric drive system, especially under low load or low heat demand conditions. In this case, excessive cooling is not only unnecessary, but also requires rapid oil temperature increase. When the torque information is less than the first torque threshold and the speed information is greater than the first speed threshold, the increase in oil temperature can significantly improve the efficiency of the motor.

[0056] When the oil temperature falls below a first oil temperature threshold, the torque information falls below a first torque threshold, and the speed information rises above a first speed threshold, the system takes appropriate measures to raise the oil temperature, thereby improving motor efficiency. In this embodiment, heat exchange between the oil cooling circuit and the water cooling circuit is intentionally blocked to prevent further drop in oil temperature. By controlling the first solenoid valve to completely block oil flow through the heat exchanger, the oil temperature can be effectively maintained or raised.

[0057] This implementation prioritizes the relationship between motor efficiency and oil temperature, particularly under low-torque, high-speed operating conditions. By comprehensively factoring in oil temperature, torque, and speed information, the system can make more intelligent decisions, optimizing motor operation and improving energy efficiency. This also enhances the EV's drivability and reliability.

[0058] Step S30: If the oil temperature, the torque information, and the speed information meet the second preset condition, heat exchange is performed between the oil cooling circuit and the water cooling circuit.

[0059] In this embodiment, the heat exchange between the oil cooling circuit and the water cooling circuit is precisely controlled to prevent the oil overheating problem that may occur when the electric vehicle is suddenly faced with high torque demand.

[0060] In one embodiment, this step is designed to take into account the thermal management challenges that the motor may face under certain conditions, especially in the unpredictable high-load driving situations that electric vehicles may encounter.

[0061] In this embodiment, when the torque and speed information meet the second preset condition, the motor's efficiency can still be improved by increasing the oil temperature. However, if the vehicle suddenly enters a high-torque driving mode, such as during rapid acceleration or hill climbing, the motor may rapidly generate a significant amount of heat. Since the oil temperature is already high, this additional heat could cause it to rise excessively, potentially damaging the motor's internal components.

[0062] To prevent this, step S30 preemptively adjusts the oil temperature by exchanging heat between the oil cooling circuit and the water cooling circuit. This allows the oil temperature to increase, improving motor efficiency while also implementing additional measures to limit the rate of oil temperature increase. Specifically, when the oil temperature, torque, and speed information meet a second preset condition, heat exchange is initiated between the oil cooling circuit and the water cooling circuit to limit the rate of oil temperature increase.

[0063] This preventative measure allows the system to maintain oil temperature within a safe operating range when faced with sudden high torque demands, ensuring reliable motor operation and the integrity of the motor's internal components. In this way, the system maintains high efficiency while also preparing for potential high-load conditions.

[0064] In this embodiment, further control is performed through steps S301 - S302 .

[0065] Step S301: Acquire a first oil temperature threshold, a second oil temperature threshold, a first torque threshold, and a first speed threshold.

[0066] In this embodiment, this step is similar to step S201 and will not be described again here.

[0067] Step S302: If the oil temperature is greater than or equal to the first oil temperature threshold and less than the second oil temperature threshold, the torque information is less than the first torque threshold, and the speed information is greater than the first speed threshold, heat exchange is performed between the oil cooling circuit and the water cooling circuit.

[0068] In this embodiment, different situations that the electric drive system may face during operation are taken into consideration, especially in preventing the oil overheating problem caused by sudden high torque.

[0069] In one embodiment, this step is based on two key conditions: first, the torque information is lower than a first torque threshold, and second, the speed information is higher than a first speed threshold.

[0070] First, the importance of the "torque information is less than the first torque threshold, and the speed information is greater than the first speed threshold" condition is that it ensures that the current motor state is in a situation where increasing the oil temperature can effectively improve motor efficiency. Therefore, oil temperature control in this environment is performed to increase the oil temperature and improve overall system performance.

[0071] Secondly, the condition "oil temperature greater than or equal to the first oil temperature threshold and less than the second oil temperature threshold" indicates that the oil temperature is already relatively low. This setting is intended to prevent the oil temperature from rapidly rising to a high temperature that could damage the motor during sudden high torque demands, such as during rapid acceleration or hill climbing. By activating heat exchange between the oil cooling circuit and the water cooling circuit at this stage, the system can preemptively slow the oil temperature rise and avoid the risks of excessive oil temperature.

[0072] In this embodiment, heat exchange does not reduce the oil temperature; rather, it serves to suppress the rate of oil temperature rise. The oil temperature will still rise during this process, thereby improving the efficiency of the entire motor. However, due to the presence of heat exchange, the rate of oil temperature rise is significantly reduced.

[0073] Step S302-1: If the oil temperature is greater than or equal to the first oil temperature threshold and less than the second oil temperature threshold, the torque information is less than the first torque threshold, and the speed information is greater than the first speed threshold, then the opening of the first solenoid valve is controlled to reach a preset first opening.

[0074] In this embodiment, the first opening degree reflects the opening and closing degree of the first solenoid valve. The higher the first opening degree, the higher the opening degree of the first solenoid valve, and the stronger the heat exchange between the oil cooling circuit and the water circuit.

[0075] In one embodiment, the first opening is preferably between 0-50%. The system controls the amount of heat exchange between the oil cooling circuit and the water cooling circuit by adjusting the opening of the first solenoid valve. Adjusting to the preset first opening allows a certain amount of coolant to pass through the heat exchanger, thereby appropriately controlling its increase rate. This measure ensures that even under sudden load increases, the oil temperature remains within a safe and efficient operating range.

[0076] Through this pre-set control strategy, step S302-1 not only steadily improves the efficiency of the motor, but also improves the system's adaptability to sudden working conditions, ensuring the performance and safety of the electric vehicle under various driving conditions.

[0077] In this embodiment, the oil cooling circuit includes a second solenoid valve, a third solenoid valve and a fourth solenoid valve, wherein the second solenoid valve is used to conduct the oil cooling circuit to cool the bearings in the motor, the third solenoid valve is used to conduct the oil cooling circuit to cool the rotor in the motor, and the fourth solenoid valve conducts the oil cooling circuit to cool the stator in the motor, wherein the second solenoid valve, the third solenoid valve and the fourth solenoid valve all adjust the degree of cooling of the corresponding components by controlling the opening of the solenoid valve.

[0078] In this embodiment, opening the oil cooling circuit refers to adding a new oil cooling branch to the existing oil cooling circuit. When one of the three solenoid valves is fully closed, it only controls the closing of the oil cooling branch for its corresponding component. When one of the three solenoid valves is suddenly opened, it facilitates the opening of the corresponding oil cooling branch. For example, opening the second solenoid valve places the bearing in the new oil cooling circuit, thereby achieving temperature reduction.

[0079] The following control strategies are also included, such as steps S401 to S404.

[0080] Step S401: Determine whether the vehicle is in a static heating state.

[0081] In one embodiment, the system first determines whether the vehicle is in a static heating state. This state typically occurs when the vehicle needs to preheat the battery in a low-temperature environment to improve performance and efficiency. Detecting the static heating state relies on the vehicle's sensor system, including temperature sensors and a vehicle status monitoring system. These sensors provide data on ambient temperature, battery status, and whether the vehicle is stationary. If the sensors detect a low-temperature environment and the vehicle is not in motion, the system determines that the vehicle has entered the static heating state.

[0082] Step S402: If the vehicle is in a static heating state, the executed control includes: the second solenoid valve is in a closed state, and the fourth solenoid valve is in an open state, so that heat exchange occurs between the oil cooling circuit and the water cooling circuit.

[0083] In one embodiment, once the vehicle is determined to be in a static heating mode, the system implements a specific control strategy. In this mode, the primary goal is to use heat from the motor drive system windings to heat the battery. Since the motor's stator generates heat while the rotor is inactive in heating mode, the system adjusts this by controlling the solenoid valves. The second solenoid valve is closed, while the fourth solenoid valve is open. This directs the primary flow from the oil pump to the stator, effectively utilizing the heat generated there to heat the battery while reducing unnecessary energy consumption due to the rotor being inactive.

[0084] This approach allows electric vehicles to effectively utilize their own electric drive system to provide the required heat to the battery while stationary, thereby improving battery performance and efficiency. This heating strategy not only improves the vehicle's overall operating efficiency in low-temperature environments, but also optimizes the motor's energy utilization, ensuring the system's economic and environmental performance.

[0085] Step S403: Determine whether the vehicle is in a boost charging state.

[0086] In one embodiment, the system first determines whether the vehicle is in boost charging mode. This occurs when the battery is being charged but the input voltage is low, requiring the motor drive system to boost the voltage for charging. The system determines whether to enter boost charging mode by monitoring parameters such as the motor's operating status, the battery's charging requirements, and the input voltage. If it detects that the battery requires charging and the input voltage is below the required level, the system initiates the boost charging process.

[0087] Step S404: If the vehicle is in the boost charging state, the executed control includes: the second solenoid valve is in the closed state, and the third solenoid valve is in the open state, so that heat exchange occurs between the oil cooling circuit and the water cooling circuit.

[0088] In one embodiment, when the vehicle enters the boost charging state, the motor's rotor generates significant heat due to electromagnetic losses. This heat generation during boost charging can exceed the level during normal driving, requiring effective heat dissipation measures to protect the motor. To this end, the system implements a specific control strategy, including adjusting the solenoid valve in the oil cooling circuit.

[0089] In this mode, the second solenoid valve is closed, while the third solenoid valve is open. This directs most of the cooling oil to the rotor for active heat dissipation. In this way, the system effectively manages the excess heat generated by the rotor during boost charging, preventing motor overheating and ensuring safe operation and long-term stability.

[0090] In summary, steps S403 and S404 work together to ensure the efficient and safe operation of the electric vehicle's electric drive system during boost charging. These steps effectively manage the additional heat generated by specific charging modes by precisely controlling the solenoid valves in the oil cooling circuit, maintaining system reliability and efficiency.

[0091] It should be pointed out that although the various steps in the above embodiments are described in a specific order, those skilled in the art will understand that in order to achieve the effect of the present application, different steps do not have to be performed in such an order. They can be performed simultaneously (in parallel) or in other orders. These changes are within the scope of protection of the present application.

[0092] It will be understood by those skilled in the art that all or part of the processes in the method for implementing the above embodiment of the present application can also be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, it can implement the steps of the above-mentioned various method embodiments. The computer program includes a computer program, and the computer program can be in source code form, object code form, executable file or some intermediate form. The computer-readable storage medium may include: any entity or device, medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory, random access memory, electric carrier signal, telecommunication signal and software distribution medium that can carry the computer program. It should be noted that the content contained in the computer-readable storage medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable storage media do not include electric carrier signals and telecommunication signals.

[0093] Furthermore, the present application also provides a control device. In a control device embodiment according to the present application, the control device includes a processor and a storage device. The storage device can be configured to store a program for executing the efficiency optimization method of the motor in the electric vehicle according to the above method embodiment. The processor can be configured to execute the program in the storage device, which includes but is not limited to the program for executing the efficiency optimization method of the motor in the electric vehicle according to the above method embodiment. For ease of explanation, only the parts related to the embodiment of the present application are shown. For specific technical details not disclosed, please refer to the method part of the embodiment of the present application. The control device can be a control device device formed by various electronic devices.

[0094] Furthermore, the present application also provides a computer-readable storage medium. In a computer-readable storage medium embodiment according to the present application, the computer-readable storage medium can be configured to store a program for executing the efficiency optimization method of the motor in the electric vehicle of the above-mentioned method embodiment, and the program can be loaded and run by the processor to implement the above-mentioned efficiency optimization method of the motor in the electric vehicle. For ease of explanation, only the parts related to the embodiment of the present application are shown. For specific technical details not disclosed, please refer to the method part of the embodiment of the present application. The computer-readable storage medium can be a storage device formed by various electronic devices. Optionally, the computer-readable storage medium in the embodiment of the present application is a non-temporary computer-readable storage medium.

[0095] Furthermore, it should be understood that since the configuration of each module is merely for the purpose of illustrating the functional units of the apparatus of the present application, the physical devices corresponding to these modules may be the processor itself, or a portion of the software in the processor, a portion of the hardware, or a combination of software and hardware. Therefore, the number of modules in the figure is merely illustrative.

[0096] Those skilled in the art will appreciate that the various modules in the device can be adaptively split or merged. Such splitting or merging of specific modules will not cause the technical solution to deviate from the principles of this application. Therefore, the technical solutions after splitting or merging will fall within the scope of protection of this application.

[0097] The relevant user personal information that may be involved in the various embodiments of this application is strictly in accordance with the requirements of laws and regulations, following the principles of legality, legitimacy and necessity, and based on the reasonable purposes of business scenarios, to process the personal information that users actively provide during the use of products / services or generated due to the use of products / services, as well as the personal information obtained with the user's authorization.

[0098] The personal information processed by the Applicant will vary depending on the specific product / service scenario and will be based on the specific scenario in which the user uses the product / service. This may involve the user's account information, device information, driving information, vehicle information, or other related information. The Applicant will treat the user's personal information and its processing with a high degree of diligence.

[0099] The Applicant attaches great importance to the security of user personal information and has taken reasonable and feasible security measures that comply with industry standards to protect user information and prevent personal information from being accessed, disclosed, used, modified, damaged or lost without authorization.

[0100] Thus far, the technical solutions of the present application have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is readily understood by those skilled in the art that the scope of protection of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present application.

Claims

1. A method for optimizing the efficiency of a motor in an electric vehicle, characterized in that: The automobile comprises an electric motor, an oil cooling circuit and a water cooling circuit, wherein the oil cooling circuit is used to dissipate heat from the automobile electric motor, and the method comprises: Obtain oil temperature, torque information and speed information in the oil cooling circuit of the car; If the oil temperature, torque information and speed information meet the first preset condition, heat exchange between the oil cooling circuit and the water cooling circuit is not performed.

2. The method for optimizing the efficiency of a motor in an electric vehicle according to claim 1, characterized in that: “If the oil temperature, torque information and speed information meet the first preset condition, heat exchange between the oil cooling circuit and the water cooling circuit is not generated”, including: Acquire a first oil temperature threshold, a first torque threshold, and a first speed threshold; If the oil temperature is less than the first oil temperature threshold, the torque information is less than the first torque threshold, and the speed information is greater than the first speed threshold, heat exchange between the oil cooling circuit and the water cooling circuit is not performed.

3. The method for optimizing the efficiency of a motor in an electric vehicle according to claim 2, characterized in that: The automobile further comprises a heat exchanger, wherein the oil cooling circuit and the water cooling circuit perform heat exchange through the heat exchanger; the heat exchanger comprises a first solenoid valve, wherein the opening of the first solenoid valve controls the heat exchange efficiency between the oil cooling circuit and the water cooling circuit.

4. The method for optimizing the efficiency of a motor in an electric vehicle according to claim 3, characterized in that: The method further includes: if the oil temperature, torque information and speed information meet a second preset condition, causing the oil cooling circuit to generate heat exchange with the water cooling circuit, wherein the heat exchange is used to suppress the rate of increase of the oil temperature.

5. The method for optimizing the efficiency of a motor in an electric vehicle according to claim 4, characterized in that: The method further includes: acquiring a first oil temperature threshold, a second oil temperature threshold, a first torque threshold, and a first rotation speed threshold; If the oil temperature, torque information and speed information meet the second preset condition, the oil cooler The circuit exchanges heat with the water cooling circuit", including: If the oil temperature is greater than or equal to the first oil temperature threshold and less than the second oil temperature threshold, the torque information is less than the first torque threshold, and the speed information is greater than the first speed threshold, heat exchange is generated between the oil cooling circuit and the water cooling circuit.

6. The method for optimizing the efficiency of a motor in an electric vehicle according to claim 5, characterized in that: "If the oil temperature is greater than or equal to the first oil temperature threshold and less than the second oil temperature threshold, the torque information is less than the first torque threshold, and the speed information is greater than the first speed threshold, heat exchange is generated between the oil cooling circuit and the water cooling circuit", including: If the oil temperature is greater than or equal to the first oil temperature threshold and less than the second oil temperature threshold, the torque information is less than the first torque threshold, and the speed information is greater than the first speed threshold, the opening of the first solenoid valve is controlled to reach a preset first opening.

7. The method for optimizing the efficiency of a motor in an electric vehicle according to claim 1, characterized in that: The oil cooling circuit includes a second solenoid valve, a third solenoid valve and a fourth solenoid valve, wherein the second solenoid valve is used to conduct the oil cooling circuit to cool the bearings in the motor, the third solenoid valve is used to conduct the oil cooling circuit to cool the rotor in the motor, and the fourth solenoid valve is used to conduct the oil cooling circuit to cool the stator in the motor, wherein the second solenoid valve, the third solenoid valve and the fourth solenoid valve all adjust the degree of cooling of the corresponding components by controlling the opening of the solenoid valve.

8. The method for optimizing the efficiency of a motor in an electric vehicle according to claim 7, characterized in that: The method further comprises: Determine whether the vehicle is in a static heating state; If the vehicle is in a static heating state, the executed control includes: the second solenoid valve is in a closed state, and the fourth solenoid valve is in an open state, so that heat exchange occurs between the oil cooling circuit and the water cooling circuit.

9. The method for optimizing the efficiency of a motor in an electric vehicle according to claim 7, characterized in that: The method further comprises: Determine whether the vehicle is in a boost charging state; If the vehicle is in a boost charging state, the control executed includes: In the pressure charging state, the executed control includes: the second solenoid valve is in a closed state, and the third solenoid valve is in an open state, so that heat exchange occurs between the oil cooling circuit and the water cooling circuit.

10. A control device, comprising a processor and a storage device, wherein the storage device is suitable for storing a plurality of computer programs, characterized in that: The computer program is suitable for being loaded and run by the processor to execute the efficiency optimization method of the motor in the electric vehicle according to any one of claims 1 to 9.

11. A computer-readable storage medium storing a plurality of computer programs, characterized in that: The computer program is suitable for being loaded and run by a processor to execute the efficiency optimization method of a motor in an electric vehicle according to any one of claims 1 to 9.

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