A control method and apparatus

Abstract

A control method and apparatus, relating to the field of control, is applicable to an electric drive system. The electric drive system includes an oil pump (401), a motor (402), a reducer (403), and a housing (404). The motor (402) and the reducer (403) are disposed within the housing (404), which stores lubricating oil. The oil pump (401) is used to pump the lubricating oil. The method includes: acquiring a first rotational speed of the motor (402), a second rotational speed of the oil pump (401), and the temperature of the lubricating oil within the housing (404); and controlling the rotational speed of the oil pump (401) to a third rotational speed based on the first rotational speed, the second rotational speed, and the temperature. In this way, by adjusting the rotational speed of the oil pump (401), the lubricating oil level and the oil pump power within the housing (404) at different oil pump rotational speeds can be changed, thereby effectively improving the overall efficiency.

Description

Technical Field

[0001] This application relates to the field of control, and more particularly to a control method and apparatus. Background Technology

[0002] The electric drive system is a core component of new energy vehicles, and pursuing high efficiency in the electric drive system has become a mainstream development demand and trend. Improving the efficiency of the electric drive system can increase the vehicle's driving range, which is one of the most important performance indicators of new energy vehicles.

[0003] Currently, electronic oil pumps are commonly used for cooling and active lubrication of motors and reducers. The function of the electronic oil pump is to deliver lubricating oil to various friction parts of the motor, so that the lubricating oil circulates in the lubrication circuit to ensure that the motor receives good cooling and lubrication.

[0004] However, when using an electronic oil pump to cool and lubricate the assembly motor and reducer, the assembly wear is significant, and the assembly efficiency is not effectively improved. Summary of the Invention

[0005] This application provides a control method and apparatus that can control the oil pump speed to a third speed based on a first motor speed, a second oil pump speed, and the temperature of the lubricating oil. This allows for active control of the lubricating oil level inside the housing by adjusting the oil pump speed, thereby changing the lubricating oil level and pump power at different pump speeds and effectively improving overall assembly efficiency.

[0006] In a first aspect, embodiments of this application provide a control method applied to an electric drive system. The electric drive system includes an oil pump, a motor, a reducer, and a housing. The motor and reducer are disposed within the housing, which stores lubricating oil. The oil pump is used to pump the lubricating oil. The method includes: acquiring a first rotational speed of the motor, a second rotational speed of the oil pump, and the temperature of the lubricating oil within the housing; and controlling the rotational speed of the oil pump to a third rotational speed based on the first rotational speed, the second rotational speed, and the temperature. Thus, embodiments of this application can effectively improve the overall efficiency by adjusting the rotational speed of the oil pump, thereby changing the lubricating oil level and pump power within the housing at different pump rotational speeds.

[0007] In one possible implementation, controlling the oil pump speed to a third speed based on a first speed, a second speed, and temperature includes: determining a temperature-related correlation, which includes the correlation between motor speed, oil pump speed, and losses; determining a first loss corresponding to the first and second speeds within the correlation; and controlling the oil pump speed to a third speed based on the first loss and the correlation. Thus, this embodiment of the application can control the oil pump speed through the correlation between motor speed, oil pump speed, and losses, thereby enabling more accurate control of the oil pump speed and effectively improving assembly efficiency.

[0008] In one possible implementation, controlling the oil pump speed to a third speed based on a first loss and a correlation includes: determining multiple second losses corresponding to the first speed in the correlation; and adjusting the oil pump speed to a third speed when one of the second losses is less than the first loss, wherein the third speed is the oil pump speed corresponding to one of the second losses. This embodiment adjusts the oil pump speed to the speed corresponding to the smaller loss, thus effectively improving assembly efficiency.

[0009] In one possible implementation, when one of the second losses is less than the first loss, the oil pump speed is adjusted to a third speed. This includes adjusting the oil pump speed to a third speed when multiple second losses are less than the first loss, wherein the third speed is the oil pump speed corresponding to the lowest loss among the multiple second losses. In this way, by adjusting the oil pump speed, losses can be minimized, thereby more effectively improving the overall assembly efficiency.

[0010] In one possible implementation, the losses include: oil churning loss and oil pump power consumption; wherein, oil churning loss is the power loss caused by the fluid resistance encountered by the reducer gear rotating in the lubricating oil in the housing.

[0011] In one possible implementation, the relationship between motor speed, oil pump speed, and losses is a continuous function. This allows for a more accurate determination of multiple secondary losses corresponding to the first speed, thereby adjusting the oil pump speed to the speed corresponding to the lowest loss and more effectively improving the overall efficiency.

[0012] Secondly, embodiments of this application provide a control device applied to an electric drive system. The electric drive system includes an oil pump, a motor, a reducer, and a housing. The motor and reducer are disposed within the housing, which stores lubricating oil. The oil pump is used to pump the lubricating oil.

[0013] The control device can be a terminal device, or a chip or chip system within a terminal device. The control device may include a processing unit. When the control device is a terminal device, the processing unit may be a processor. The control device may also include a storage unit, which may be a memory. The storage unit stores instructions, and the processing unit executes the instructions stored in the storage unit to cause the terminal device to implement a control method described in the first aspect or any possible implementation of the first aspect. When the control device is a chip or chip system within a terminal device, the processing unit may be a processor. The processing unit executes the instructions stored in the storage unit to cause the terminal device to implement a control method described in the first aspect or any possible implementation of the first aspect. The storage unit may be a storage unit within the chip (e.g., a register, cache, etc.), or a storage unit located outside the chip within the terminal device (e.g., read-only memory, random access memory, etc.).

[0014] For example, the processing unit is used to acquire a first speed of the motor, a second speed of the oil pump, and the temperature of the lubricating oil in the housing; the processing unit is also used to control the speed of the oil pump to a third speed based on the first speed, the second speed, and the temperature.

[0015] In one possible implementation, the processing unit is further configured to determine the temperature-related correlation based on the temperature, including the correlation between motor speed, oil pump speed and loss; the processing unit is further configured to determine the first loss corresponding to the first speed and the second speed in the correlation; the processing unit is further configured to control the oil pump speed to a third speed based on the first loss and the correlation.

[0016] In one possible implementation, the processing unit is further configured to determine multiple second losses corresponding to the first rotational speed in the association relationship; if one of the second losses is less than the first loss, the rotational speed of the oil pump is adjusted to a third rotational speed, wherein the third rotational speed is the oil pump rotational speed corresponding to one of the second losses.

[0017] In one possible implementation, the processing unit is further configured to: adjust the oil pump speed to a third speed when multiple second losses are less than the first loss, wherein the third speed is the oil pump speed corresponding to the lowest loss among the multiple second losses.

[0018] In one possible implementation, the losses include: oil churning loss and oil pump power consumption; wherein, oil churning loss is the power loss caused by the fluid resistance encountered by the reducer gear rotating in the lubricating oil in the housing.

[0019] In one possible implementation, the motor speed, oil pump speed, and losses are in a continuous functional relationship.

[0020] Thirdly, embodiments of this application provide a control device, including: a processor, configured to call a program in a memory to implement any control method in the first aspect or any possible implementation of the first aspect.

[0021] Fourthly, this application also provides a powertrain including any control device according to the second aspect or any possible implementation thereof. The powertrain further includes an inverter, a motor, and a reducer. The inverter converts direct current (DC) into alternating current (AC) and transmits it to the motor; the motor converts AC into mechanical energy to drive the vehicle; and the reducer converts the output speed of the motor shaft.

[0022] Fifthly, this application also provides a vehicle including the powertrain and battery pack described in the fourth aspect, the battery pack being used to provide direct current to an inverter.

[0023] In a sixth aspect, embodiments of this application provide a chip, including: a processor and an interface circuit, the interface circuit being used to communicate with other devices, and the processor being used to run computer programs or instructions to perform the control method described in any of the implementations of the first aspect.

[0024] The communication interface in the chip can be an input / output interface, pins, or circuits.

[0025] In one possible implementation, the chip or chip system described above in this application further includes at least one memory storing instructions. The memory can be an internal storage unit of the chip, such as a register or cache, or it can be a storage unit of the chip itself (e.g., read-only memory, random access memory, etc.).

[0026] In a seventh aspect, embodiments of this application provide a computer-readable storage medium storing a computer program or instructions that, when executed on a computer, cause the computer to perform the control method described in any implementation of the first aspect.

[0027] It should be understood that the second to seventh aspects of the embodiments of this application correspond to the technical solutions of the first aspect of the embodiments of this application, and the beneficial effects achieved by each aspect and the corresponding feasible implementation are similar, and will not be described again. Attached Figure Description

[0028] Figure 1 A schematic diagram of a water-cooled motor electric drive assembly provided in an embodiment of this application;

[0029] Figure 2A schematic diagram illustrating the oil churning behavior of a reducer when using water cooling for heat dissipation, as provided in an embodiment of this application.

[0030] Figure 3 A schematic diagram of an oil-cooled motor electric drive assembly provided in an embodiment of this application;

[0031] Figure 4 A schematic diagram of an electric drive assembly system provided in an embodiment of this application;

[0032] Figure 5 This is a schematic diagram of the basic internal structure of an electric motor provided in an embodiment of this application;

[0033] Figure 6 A flowchart illustrating a control method provided in an embodiment of this application;

[0034] Figure 7 This is a schematic diagram illustrating the acquisition of the first rotational speed of the motor according to an embodiment of this application;

[0035] Figure 8 A flowchart illustrating a control method provided in an embodiment of this application;

[0036] Figure 9 A flowchart illustrating a control method provided in an embodiment of this application;

[0037] Figure 10 This is a schematic diagram of the structure of a control device provided in an embodiment of this application;

[0038] Figure 11 This is a schematic diagram of the structure of a powertrain provided in an embodiment of this application;

[0039] Figure 12 A schematic diagram of the structure of a vehicle provided in an embodiment of this application;

[0040] Figure 13 This is a schematic diagram of the structure of a chip provided in an embodiment of this application. Detailed Implementation

[0041] To facilitate a clear description of the technical solutions in the embodiments of this application, the terms "first" and "second" are used in the embodiments of this application to distinguish identical or similar items with essentially the same function and effect. For example, the first speed and the second speed are only used to distinguish the speeds of the oil pump and the motor, and do not limit their order. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and the terms "first" and "second" are not necessarily different.

[0042] It should be noted that, in this application, the terms "exemplary" or "for example" are used to indicate that something is being described as an example, illustration, or illustration. Any embodiment or design described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or design solutions. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0043] In this application, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can mean: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0044] An electric drive system can include a motor controller, a motor, and a reducer. Efficiency losses in any of these components affect the overall efficiency of the electric drive system, thus impacting the vehicle's driving range. Among these, the oil churning losses in the reducer gears are a significant component of the efficiency losses in the electric drive system.

[0045] Typically, when an electric motor is running at high speed, the motor stator generates a large amount of heat. If this heat is not dissipated in time, it will seriously affect the motor's reliability and the overall vehicle performance. Therefore, it is necessary to cool the motor.

[0046] Currently, the most commonly used methods for motor cooling include water cooling and oil cooling.

[0047] For example, Figure 1 This is a schematic diagram of a water-cooled motor drive assembly, as shown below. Figure 1 As shown, the motor stator is cooled by coolant (e.g., antifreeze), and the gearbox is lubricated by lubricating oil. For example, the motor can be cooled by using a water pump to drive the coolant to accelerate its flow.

[0048] The lubricating oil is located inside the housing, and the reducer uses the main reducer gear to agitate the oil, providing splash lubrication to the gears and bearings. For example... Figure 2This diagram illustrates the oil churning process of a reducer when using water cooling. The reducer consists of several gears, shafts, and bearings. The gears are immersed in an oil sump, and lubricating oil is carried to the meshing tooth surfaces by the rotation of the gears. To prevent excessive power loss during oil churning, the gears should not be immersed too deeply in the oil sump; for example, the immersion depth should be one-quarter of the gear radius. The distance between the top of the main reducer gear and the bottom of the housing can be greater than 5mm to prevent sludge or debris from the bottom of the oil sump from accumulating on the gear meshing surfaces and increasing friction.

[0049] However, when water cooling is used to dissipate heat from the motor, a larger volume of lubricating oil is required to achieve proper lubrication of the gears and bearings, resulting in higher oil churning losses in the reducer gears. Furthermore, the lubricating oil level cannot be adjusted according to changes in the overall assembly's operating conditions. In other words, once the amount of lubricating oil is determined, the oil churning loss is also fixed and cannot be optimized.

[0050] For example, Figure 3 A schematic diagram is shown illustrating the use of oil cooling to dissipate heat from the motor, as follows: Figure 3 As shown, an electronic oil pump can be used to pump out lubricating oil from the housing to achieve cooling and active lubrication of the motor and reducer.

[0051] When oil cooling is used to dissipate heat from the motor, the lubricating oil circulation loop has a certain oil storage function, which can reduce the fluid level in the reducer and thus reduce churning losses. However, when using an oil pump for cooling and lubrication, only the heat dissipation and lubrication of the assembly are considered, without actively adjusting the fluid level of the lubricating oil in the cavity through the oil pump to optimize churning losses. Therefore, the churning losses are not optimal under different assembly operating conditions.

[0052] Based on the problems of the above two methods, this application provides a control method that can effectively improve the efficiency of the assembly by adjusting the speed of the oil pump, changing the level of the lubricating oil inside the cavity and the power of the oil pump at different oil pump speeds.

[0053] The control method provided in this application embodiment can be applied to, for example... Figure 4 The powertrain system shown. The powertrain system 400 may include an oil pump 401, an electric motor 402, a reducer 403, and a housing 404.

[0054] The motor 402 and the reducer 403 are housed in the housing 404, which stores lubricating oil. The oil pump 401 is used to pump the lubricating oil to achieve cooling and lubrication of the motor 402 and the reducer 403.

[0055] Motor 402 is an electromagnetic device that converts or transmits electrical energy based on the law of electromagnetic induction. Its main function is to generate driving torque to power electrical appliances or various machines. Specifically, motor 402 can be used in electric vehicles, such as pure electric vehicles, range-extended electric vehicles, hybrid electric vehicles, fuel cell vehicles, and new energy vehicles.

[0056] Figure 5 A schematic diagram of the internal structure of an electric motor is shown. (For example...) Figure 5 As shown, the motor 500 mainly includes: a stator 510, a shaft 540, a rotor 550, a housing 560, a front cover 570, a rear cover 580, and a motor bearing 590. The stator 510 has stator windings wound around it, and during winding, its two ends extend outward from the two ends of the stator core to form the stator winding ends 5301 and 5302. The relationship between the various components of the motor is as follows: the inner walls of the housing 560, the front cover 570, and the rear cover 580 form a cavity. Within this cavity, from the outermost to the innermost ring, the stator 510, the rotor 550, and the shaft 540 are arranged sequentially. That is, the rotor 550 is fitted over the shaft 540, and the stator 510 is fitted over the rotor 550. The stator 510 is fixed within the housing 560, and the rotor 550 drives the shaft 540 to rotate. The two ends of the rotating shaft 540 are rotatably connected to the two side end faces (front end cover 570 and rear end cover 580) opposite to the housing 560 via the motor bearing 590, and one end can also be connected to the input shaft gear of the reducer from one side end face.

[0057] The reducer 403 includes a parallel shaft gear reducer and a planetary gear reducer. The input gear of each parallel shaft gear reducer is connected to a motor 402, and the output gear is connected to the driving element of a planetary gear reducer. The driven element of each planetary gear reducer is connected to a power output shaft. Since the gears in the parallel shaft gear reducer are less difficult to machine at the same speed, directly connecting the parallel shaft gear reducer to the drive motor and then connecting the planetary gear reducer to the parallel shaft gear reducer can reduce the speed of the planetary gear reducer, thereby reducing the precision requirements for the gear machining of the planetary gear reducer.

[0058] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be implemented independently or in combination with each other. The same or similar concepts or processes may not be described again in some embodiments.

[0059] Figure 6 This is a flowchart illustrating a control method provided in an embodiment of this application. This method is applicable to the above-mentioned... Figure 4 The corresponding powertrain system. For example... Figure 6As shown in the embodiments of this application, a control method may include the following steps:

[0060] S601: Obtain the first speed of the motor, the second speed of the oil pump, and the temperature of the lubricating oil inside the housing.

[0061] One possible interpretation is that the first speed of the motor is the speed of the motor rotor.

[0062] One possible implementation is to use a photoelectric sensor to obtain the first rotational speed of the motor. This photoelectric sensor can be a projected photoelectric sensor or a reflective photoelectric sensor. An exemplary schematic diagram of using a projected photoelectric sensor to obtain the first rotational speed of the motor is shown below. Figure 7 As shown, a test disk, such as a toothed disk or a perforated disk, is mounted on the motor shaft of the electric vehicle under test. The disk has Z uniformly spaced grooves or holes, where Z can be 60 or an integer multiple of 60. When a light beam passes through a groove or hole, it is projected onto a photodiode, generating an electrical signal. When the light beam is blocked by a part of the disk without holes, the photodiode receives no signal. Therefore, the frequency of the pulse signal generated by the photodiode is proportional to the motor speed.

[0063] In one possible implementation, the temperature of the lubricating oil inside the housing can be obtained by a temperature sensor.

[0064] It is understood that the first speed of the motor, the second speed of the oil pump, and the temperature of the lubricating oil in the housing can be obtained in any possible form. The embodiments of this application do not limit the specific method of obtaining these parameters.

[0065] S602: Based on the first speed, the second speed, and the temperature, control the oil pump speed to the third speed.

[0066] One possible implementation is to input the first rotational speed, the second rotational speed, and the temperature into a pre-trained model, and the output result is the third rotational speed of the oil pump.

[0067] One possible implementation is to input the first rotational speed, the second rotational speed, and the temperature into a pre-determined calculation formula, and then calculate the third rotational speed of the oil pump.

[0068] One possible implementation involves obtaining different oil pump and motor speeds at varying oil temperatures through multiple tests, and establishing a table showing the relationship between these three speeds. By consulting the table, the oil pump speed is determined to be the third speed.

[0069] In this embodiment of the application, other possible methods can also be used to control the oil pump speed to a third speed based on the first speed, the second speed and the temperature, depending on the actual application scenario. This embodiment of the application does not limit this.

[0070] In this embodiment, the lubricating oil level inside the housing can be actively controlled by adjusting the oil pump speed, thereby changing the lubricating oil level and pump power at different oil pump speeds and effectively improving the overall efficiency.

[0071] exist Figure 1 Based on the corresponding embodiments, one possible implementation is as follows: Figure 8 As shown, S602 includes:

[0072] S801: Determine the correlation between temperature and the corresponding temperature, including the correlation between motor speed, oil pump speed and loss.

[0073] In possible implementations, losses can be considered as assembly losses. These assembly losses can include: motor losses, bearing losses, oil churning losses, and oil pump power consumption. Oil churning losses are related to the lubricating oil level in the housing, while oil pump power consumption is related to the oil pump speed.

[0074] In possible implementations, losses may include one or more types of assembly losses.

[0075] In one possible implementation, this correlation can be based on prior knowledge. This prior knowledge could be a table established by testing the relationship between different oil pump speeds and motor speeds and corresponding losses at different oil temperatures. By querying the table, the correlation between the obtained lubricating oil temperature and the corresponding relationship can be obtained.

[0076] It is understood that the relationships in the embodiments of this application may also be in the form of bar charts, line charts, or other forms of representation, and the embodiments of this application do not impose specific limitations.

[0077] S802: Determine the first loss corresponding to the first speed and the second speed in the correlation relationship.

[0078] In possible interpretations, the first loss can be the assembly loss corresponding to the first speed and the second speed, or the first loss can include one or more of the assembly losses.

[0079] One possible implementation is to determine the first loss corresponding to the first speed and the second speed by looking up a table.

[0080] For example, tables can be created by testing the relationship between different oil pump speeds and motor speeds and their corresponding losses at oil temperatures of 30℃, 40℃, 50℃, and 60℃. This results in four tables. When the oil temperature is 30℃, the first speed and the first loss corresponding to the second speed can be determined in the table by querying the relationship between different oil pump speeds and motor speeds and their corresponding losses at 30℃.

[0081] S803: Based on the first loss and the correlation, control the oil pump speed to the third speed.

[0082] In one possible implementation, based on the first loss corresponding to the first and second rotational speeds, and within the obtained correlation between lubricating oil temperatures, multiple loss values ​​corresponding to the first rotational speed are determined. Among these multiple loss values, it is determined whether there exists a loss value smaller than the first loss. If a loss value smaller than the first loss exists, the third rotational speed is the rotational speed corresponding to one of these smaller loss values. If no loss value smaller than the first loss exists, the oil pump rotational speed is kept constant; this can be understood as the third rotational speed being the same as the second rotational speed.

[0083] In one possible implementation, based on the first loss corresponding to the first and second rotational speeds, and within the obtained correlation of lubricating oil temperatures, multiple loss values ​​corresponding to the first rotational speed are determined. Among these multiple loss values, it is determined whether there is a loss value smaller than the first loss. If multiple loss values ​​smaller than the first loss exist, the oil pump speed is adjusted to the speed corresponding to the lowest loss among these smaller loss values. If no loss value smaller than the first loss exists, the oil pump speed is kept constant; this can be understood as the third rotational speed being the same as the second rotational speed.

[0084] In this embodiment, the oil pump speed can be controlled by the correlation between motor speed, oil pump speed and losses, thereby allowing for more accurate adjustment of the oil pump speed and effectively improving the overall efficiency.

[0085] exist Figure 8 Based on the corresponding embodiments, in one possible implementation, the losses include: oil stirring losses and oil pump power consumption.

[0086] Among them, oil churning loss is the power loss caused by the resistance of the fluid as the reducer gear rotates in the lubricating oil in the housing. Oil pump power consumption is related to the oil pump speed; for example, the faster the oil pump speed, the greater the oil pump power consumption; the slower the oil pump speed, the greater the oil pump power consumption.

[0087] One possible interpretation is that oil churning loss is related to the lubricating oil level in the housing, which in turn is related to the oil pump speed. For example, the faster the oil pump speed, the more lubricating oil is pumped out, resulting in less lubricating oil in the housing and a lower oil level. This leads to less power loss due to fluid resistance as the reducer gears rotate within the housing's lubricating oil, and therefore, less oil churning loss. Conversely, the slower the oil pump speed, the less lubricating oil is pumped out, resulting in a higher lubricating oil level in the housing. This leads to greater power loss due to fluid resistance as the reducer gears rotate within the housing's lubricating oil, and therefore, greater oil churning loss.

[0088] In this embodiment, by adjusting the oil pump speed according to the motor's initial speed and the lubricating oil temperature, the amount of lubricating oil in the motor reducer chamber can be changed, and the oil level can be adjusted, thereby minimizing the sum of oil churning losses and oil pump power consumption. This reduces assembly losses and improves assembly efficiency.

[0089] exist Figure 8 Based on the corresponding embodiments, one possible implementation is as follows: Figure 9 As shown, S803 includes:

[0090] S901: Determine multiple second losses corresponding to the first rotational speed in the correlation relationship.

[0091] In one possible implementation, this association can be prior knowledge. This prior knowledge could be a table established by testing the relationship between different oil pump speeds and motor speeds at different oil temperatures and the corresponding losses. By querying the table, multiple secondary losses corresponding to the first speed can be determined within the association. These losses include: oil churning losses and oil pump power consumption.

[0092] S902: If one of the second losses is less than the first loss, adjust the oil pump speed to the third speed.

[0093] The third rotational speed is the oil pump speed corresponding to one of the second losses.

[0094] For example, Table 1 shows the relationship between different oil pump speeds and motor speeds and corresponding losses when the oil temperature is 40°C.

[0095] Table 1

[0096]

[0097] If the temperature of the lubricating oil is 40℃, the first rotational speed is 300 rpm, and the second rotational speed is 500 rpm, then by referring to the table, the first loss corresponding to the first and second rotational speeds is determined to be 134.9195812, and the multiple second losses corresponding to the first rotational speed are 137.4877539, 136.7111623, 129.3901122, and 149.8224251, respectively. Among these, one of the second losses, 129.3901122, is less than the first loss. Therefore, the third rotational speed is the oil pump speed of 1500 rpm corresponding to the second loss 129.3901122.

[0098] If the temperature of the lubricating oil is 40℃, the first speed is 300 rpm, and the second speed is 1000 rpm, then by referring to the table, the first loss corresponding to the first and second speeds is determined to be 136.7111623, and the multiple second losses corresponding to the first speed are 137.4877539, 134.9195812, 129.3901122, and 149.8224251, respectively. Since the second losses 129.3901122 and 134.9195812 are both less than the first loss, the third speed is either the oil pump speed of 1500 rpm corresponding to the second loss 129.3901122, or the oil pump speed of 500 rpm corresponding to the second loss 134.9195812.

[0099] In one possible implementation, if one of the second losses is less than the first loss, and if the pump speed corresponding to one of the second losses is not less than the second speed, the pump speed is adjusted to the speed corresponding to that second loss. If the pump speed corresponding to that second loss is less than the second speed, the third speed remains unchanged from the original second speed.

[0100] One possible interpretation is that, under different operating conditions, the lubricating oil level must reach a certain value to ensure the cooling and lubrication requirements of the assembly system. When the oil pump speed is adjusted to a speed lower than the second speed, the amount of oil pumped decreases, potentially leading to insufficient cooling and lubrication. Therefore, to ensure the cooling and lubrication requirements of the assembly system, the third speed can be adjusted so that the oil pump speed corresponding to the second loss is not less than the oil pump speed corresponding to the second speed. In this way, the assembly efficiency can be effectively improved while meeting the cooling and lubrication requirements of the assembly system.

[0101] For example, as shown in Table 1, if the temperature of the lubricating oil is 40℃, the first rotational speed is 400 rpm, and the second rotational speed is 500 rpm, then by looking up the table, the first loss corresponding to the first and second rotational speeds can be determined to be 242.16 rpm, and the multiple second losses corresponding to the first rotational speed are 254.7495079, 242.3020135, 213.3399312, and 262.8393466, respectively. Among them, the second loss of 129.3901122 is less than the first loss, and the oil pump speed of 1500 rpm corresponding to the second loss of 213.3399312 is not less than the second rotational speed of 500 rpm. Therefore, the third rotational speed is the oil pump speed of 1500 rpm corresponding to the second loss of 213.3399312.

[0102] If the temperature of the lubricating oil is 40℃, the first speed is 100 rpm, and the second speed is 500 rpm, then by referring to the table, the first loss corresponding to the first and second speeds is determined to be 19.10806283, and the multiple second losses corresponding to the first speed are 14.88473822, 19.75720568, 21.43655737, and 23.62649258, respectively. The second loss of 14.88473822 is less than the first loss, but the oil pump speed of 0 corresponding to the second loss of 14.88473822 is less than the second speed of 500 rpm. Therefore, the oil pump maintains its original second speed.

[0103] This application embodiment determines multiple second losses corresponding to a first rotational speed in the association relationship. When one of the second losses is less than the first loss, the rotational speed of the oil pump is adjusted to the oil pump speed corresponding to one of the second losses. In this way, by adjusting the rotational speed of the oil pump, the height of the lubricating oil level in the cavity and the oil pump power under different oil pump speeds can be changed, thereby effectively improving the efficiency of the assembly.

[0104] exist Figure 9 Based on the embodiments, in one possible implementation, S902 includes: when multiple second losses are less than the first loss, adjusting the speed of the oil pump to the oil pump speed corresponding to the lowest loss among the multiple second losses.

[0105] For example, Table 1 shows the relationship between different oil pump speeds and motor speeds and corresponding losses when the oil temperature is 40°C.

[0106] If the temperature of the lubricating oil is 40℃, the first speed is 300 rpm, and the second speed is 1000 rpm, then by referring to the table, the first loss corresponding to the first and second speeds is determined to be 136.7111623, and the multiple second losses corresponding to the first speed are 137.4877539, 134.9195812, 129.3901122, and 149.8224251, respectively. Among them, the second losses 129.3901122 and 134.9195812 are both less than the first loss. Therefore, the third speed is the oil pump speed of 1500 rpm corresponding to the lowest loss among the multiple second losses, 129.3901122.

[0107] In a possible implementation, when multiple second losses are less than the first loss, and when the oil pump speed corresponding to multiple second losses is not less than the second speed, the third speed is the oil pump speed corresponding to the lowest loss among the multiple second losses.

[0108] For example, as shown in Table 1, if the temperature of the lubricating oil is 40℃, the first rotational speed is 200 rpm, and the second rotational speed is 1000 rpm, then by looking up the table, the first loss corresponding to the first and second rotational speeds can be determined to be 100.1577143 rpm, and the multiple second losses corresponding to the first rotational speed are 24.91105675 rpm, 117.8515183 rpm, 116.3571159 rpm, and 28.18579267 rpm. Among them, the second losses 24.91105675 rpm and 28.18579267 rpm are less than the first losses, but the oil pump speed 0 rpm corresponding to the second loss 24.91105675 rpm is less than the second rotational speed, and the oil pump speed 28.18579267 rpm corresponding to the second loss 24.91105675 rpm is not less than the second rotational speed. Therefore, the third rotational speed is the oil pump speed of 1500 rpm corresponding to the second loss 28.18579267 rpm.

[0109] In this embodiment, when multiple second losses are less than the first loss, the oil pump speed is adjusted to the oil pump speed corresponding to the lowest loss among the multiple second losses. This allows for the minimum loss by adjusting the oil pump speed, thereby more effectively improving the overall assembly efficiency.

[0110] Based on any of the above embodiments, in one possible implementation, the motor speed, oil pump speed, and losses are in a continuous functional relationship.

[0111] In one possible interpretation, when the correlation is established as a table showing the relationship between different oil pump speeds and motor speeds at different oil temperatures and their corresponding losses, the test data is discrete, making it impossible to accurately determine the multiple second losses corresponding to the first speed. For example, when the first speed is 150, due to the discreteness of the values ​​during the test, the relationship between different motor speeds and their corresponding losses at the first speed of 150 was not tested. Therefore, the multiple second losses at the first speed of 150 cannot be directly determined from Table 1.

[0112] Therefore, one possible implementation is to establish a table based on the relationship between different oil pump speeds and motor speeds and corresponding losses at different oil temperatures, and then combine it with interpolation methods, such as interpolating a continuous function on the discrete data in the table, so that the continuous curve passes through all the discrete data points, thus obtaining a continuous functional relationship between motor speed, oil pump speed and losses.

[0113] One possible implementation is to use the different oil pump speeds and motor speeds obtained at different oil temperatures, along with the corresponding losses, as samples for training a neural network model to obtain a continuous functional relationship between motor speed, oil pump speed, and losses.

[0114] After obtaining the first motor speed, the second oil pump speed, and the temperature of the lubricating oil in the housing, multiple second losses corresponding to the first speed are determined through the functional relationship corresponding to the temperature, thereby controlling the oil pump speed. The method for controlling the oil pump speed corresponds to that described in the above embodiments and will not be repeated here.

[0115] In this embodiment, the motor speed, oil pump speed, and losses are in a continuous functional relationship. This allows for a more accurate determination of the multiple second losses corresponding to the first speed, thereby adjusting the oil pump speed to the speed corresponding to the lowest loss and more effectively improving the overall efficiency.

[0116] The above combination Figures 4-9 The methods described in the embodiments of this application have been explained. The control apparatus for executing the above methods, provided in the embodiments of this application, is described below. Those skilled in the art will understand that the methods and apparatus can be combined with and referenced in conjunction with each other, and the control apparatus provided in the embodiments of this application can execute the steps of the above control method.

[0117] The following example illustrates how functional modules are divided according to their respective functions:

[0118] like Figure 10 As shown, Figure 10 A schematic diagram of the control device provided in an embodiment of this application is shown. The control device includes a processing unit 1001. The processing unit 1001 is used to perform the step of controlling the oil pump speed.

[0119] In one example, taking the control device as a terminal device or a chip or chip system applied in a terminal device, the processing unit 1001 is used to support the control device in executing S601 to S602, S801 to S803 or S901 and S902 in the above embodiments.

[0120] In one possible embodiment, the control device may further include a communication unit 1002 and a storage unit 1003. The processing unit 1001, the communication unit 1002, and the storage unit 1003 are connected via a communication bus.

[0121] The storage unit 1003 may include one or more memories, which may be devices in one or more devices or circuits used to store programs or data.

[0122] The storage unit 1003 can exist independently and be connected to the processing unit 1001 of the control device via a communication bus. Alternatively, the storage unit 1003 can be integrated with the processing unit.

[0123] Control devices can be used in communication equipment, circuits, hardware components, or chips.

[0124] Taking the control device as an example, which is the terminal device in this embodiment, the communication unit 1002 can be an input or output interface, pin, or circuit, etc. For example, the storage unit 103 can store computer-executable instructions for the methods of the terminal device, so that the processing unit 1001 executes the methods of the terminal device in the above embodiments. The storage unit 1003 can be a register, cache, or RAM, etc., and can be integrated with the processing unit 101. The storage unit 1003 can be ROM or other types of static storage devices capable of storing static information and instructions, and can be independent of the processing unit 1001.

[0125] This application provides a control device, which includes one or more modules for implementing the above-described functions. Figures 4-8 The methods included in the steps described above, wherein one or more modules can be used in conjunction with the above. Figures 4-8 The steps included in the method correspond to the steps in the method. Specifically, in each step of the method executed by the terminal device in the embodiments of this application, the terminal device has a unit or module that executes each step of the method. For example, a module that performs the control of the oil pump speed can be called a processing module. A module that performs the step of message or data processing on the control device side can be called a communication module.

[0126] Figure 11 This is a schematic diagram of the structure of a powertrain provided in an embodiment of this application, as shown below. Figure 11 As shown, the powertrain includes a control unit 1101, an inverter 1102, a motor 1103, and a reducer 1104.

[0127] Control device 1101 can correspond to Figure 10 The details described herein will not be repeated in the embodiments of this application.

[0128] Inverter 1102 is used to convert DC power into AC power and then transmit it to motor 1103.

[0129] Motor 1103 is used to convert alternating current into mechanical energy to drive a vehicle.

[0130] The speed reducer 1104 is used to convert the output speed of the motor shaft of the motor 1103.

[0131] Figure 12 This is a schematic diagram of the structure of a vehicle provided in an embodiment of this application. Figure 12 As shown, the vehicle includes: a power battery pack 1201 and a powertrain 1202.

[0132] Among them, powertrain 1202 can be found Figure 11 The details described herein will not be repeated here.

[0133] The power battery pack 1201 provides DC power to the inverter of the powertrain 200.

[0134] Figure 13 This is a schematic diagram of the structure of chip 130 provided in an embodiment of the present invention. Chip 130 includes one or more (including two) processors 1313 and communication interfaces 1330.

[0135] In one possible embodiment, such as Figure 13 The illustrated chip 130 also includes a memory 1340, which may include read-only memory and random access memory, and provides operation instructions and data to the processor 1313. A portion of the memory 1340 may also include non-volatile random access memory (NVRAM).

[0136] In some implementations, memory 1340 stores executable modules or data structures, or subsets thereof, or extended sets thereof:

[0137] In this embodiment of the invention, the corresponding operation is executed by calling the operation instructions stored in the memory 1340 (which may be stored in the operating system).

[0138] One possible implementation is that the chips used in terminal devices, wireless access network devices, or session management network elements have similar structures, and different devices can use different chips to achieve their respective functions.

[0139] Processor 1313 controls the operation of the terminal device; processor 1313 can also be referred to as a central processing unit (CPU). Memory 1340 may include read-only memory and random access memory, and provides instructions and data to processor 1313. A portion of memory 1340 may also include non-volatile random access memory (NVRAM). For example, in an application, memory 1340, communication interface 1330, and memory 1340 are coupled together via bus system 1320, which, in addition to a data bus, may also include a power bus, control bus, and status signal bus, etc. However, for clarity, in... Figure 13 The general labeled all buses as Bus System 1320.

[0140] The communication unit described above can be an interface circuit or communication interface of the device, used to receive signals from other devices. For example, when the device is implemented as a chip, the communication unit is an interface circuit or communication interface used by the chip to receive or send signals from other chips or devices.

[0141] The methods disclosed in the above embodiments of the present invention can be applied to processor 1310, or implemented by processor 1010. Processor 1310 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the integrated logic circuit of the hardware in processor 1310 or by instructions in the form of software. The processor 1310 may be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of the present invention can be directly embodied in the execution of a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules may be located in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. The storage medium is located in memory 1040. Processor 1310 reads the information in memory 1340 and, in conjunction with its hardware, completes the steps of the above method.

[0142] In one possible implementation, the communication interface 1330 is used to execute Figures 4-9 The illustrated embodiments describe the steps of receiving and transmitting data from the terminal device, wireless access network device, or session management network element. Processor 1310 is used to execute... Figures 4-9 The processing steps of the terminal device in the illustrated embodiment.

[0143] In the above embodiments, the instructions stored in the memory for execution by the processor can be implemented in the form of a computer program product. The computer program product can be pre-written into the memory, or it can be downloaded and installed into the memory as software.

[0144] A computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the flow or function according to the embodiments of this application is generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a server or data center that integrates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives, SSDs), etc.

[0145] This application also provides a computer-readable storage medium. The methods described in the above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any combination thereof. If implemented in software, the functionality can be stored as one or more instructions or code on or transmitted on a computer-readable medium. A computer-readable medium can include computer storage media and communication media, and can also include any medium that can transfer a computer program from one place to another. The storage medium can be any target medium accessible by a computer.

[0146] As one possible design, a computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disc storage, disk storage or other magnetic storage device, or any other medium targeted to carry or to store the required program code in the form of instructions or data structures, and accessible by a computer. Furthermore, any connection is appropriately referred to as a computer-readable medium. For example, if software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave, then coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. As used herein, disks and optical discs include optical discs (CDs), laser discs, optical discs, digital versatile optical discs (DVDs), floppy disks, and Blu-ray discs, where disks typically reproduce data magnetically, while optical discs optically reproduce data using lasers. Combinations of the above should also be included within the scope of computer-readable media. The above descriptions are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be covered within the scope of protection of the present invention. Therefore, the scope of protection of this invention should be determined by the scope of the claims.

[0147] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A control method, characterized in that, An application is made in an electric drive system, the electric drive system including an oil pump, a motor, a reducer, and a housing, the motor and the reducer being disposed within the housing, the housing storing lubricating oil, and the oil pump being used to pump the lubricating oil; the method includes: The first rotational speed of the motor, the second rotational speed of the oil pump, and the temperature of the lubricating oil inside the housing are obtained. Based on the temperature, determine the correlation corresponding to the temperature, including the correlation between motor speed, oil pump speed and loss; In the association relationship, a first loss corresponding to the first rotational speed and the second rotational speed, and a plurality of second losses corresponding to the first rotational speed are determined; If one of the second losses is less than the first loss, the speed of the oil pump is adjusted to a third speed; wherein the third speed is the oil pump speed corresponding to the second loss.

2. The method according to claim 1, characterized in that, Also includes: If there are multiple instances of the second loss being less than the first loss, then the speed of the oil pump is adjusted to the third speed, wherein the third speed is the oil pump speed corresponding to the lowest loss among the multiple instances of the second loss.

3. The method according to claim 1 or 2, characterized in that, The losses include: oil churning loss and oil pump power consumption; wherein, the oil churning loss is the power loss caused by the resistance of the fluid as the reducer gear rotates in the lubricating oil in the housing.

4. The method according to claim 1, characterized in that, In the aforementioned correlation, the motor speed, oil pump speed, and losses are in a continuous functional relationship.

5. A control device, characterized in that, An electric drive system is applied to an electric drive system, the electric drive system including an oil pump, a motor, a reducer, and a housing, wherein the motor and the reducer are disposed within the housing, the housing stores lubricating oil, and the oil pump is used to pump the lubricating oil; the device includes: The processing unit is used to obtain the first rotational speed of the motor, the second rotational speed of the oil pump, and the temperature of the lubricating oil inside the housing; The processing unit is further configured to determine the correlation relationship corresponding to the temperature based on the temperature, the correlation relationship including the correlation relationship between motor speed, oil pump speed and loss; In the association relationship, a first loss corresponding to the first rotational speed and the second rotational speed, and a plurality of second losses corresponding to the first rotational speed are determined; If one of the second losses is less than the first loss, the speed of the oil pump is adjusted to a third speed; wherein the third speed is the oil pump speed corresponding to the second loss.

6. The apparatus according to claim 5, wherein the processing unit is further configured to: If there are multiple instances where the second loss is less than the first loss, then the speed of the oil pump is adjusted to the third speed, wherein... The third rotational speed is the oil pump rotational speed corresponding to the lowest loss among the multiple second losses.

7. The apparatus according to claim 5 or 6, characterized in that, The losses include: oil churning loss and oil pump power consumption; wherein, the oil churning loss is the power loss caused by the resistance of the fluid as the reducer gear rotates in the lubricating oil in the housing.

8. The apparatus according to claim 5, characterized in that, In the aforementioned correlation, the motor speed, oil pump speed, and losses are in a continuous functional relationship.

9. A control device, characterized in that, include: A processor for invoking a program in memory to perform the method according to any one of claims 1-4.

10. A powertrain comprising the control device according to any one of claims 5-8, the powertrain further comprising: Inverters, motors, and speed reducers; The inverter is used to convert direct current into alternating current and then transmit it to the motor; The motor is used to convert the alternating current into mechanical energy to drive the vehicle. The speed reducer is used to convert the output speed of the motor shaft of the motor.

11. A vehicle, characterized in that, The vehicle includes the powertrain and battery pack of claim 10, the battery pack being used to provide direct current to the inverter.

12. A chip, characterized in that, include: A processor and an interface circuit, the interface circuit being used to communicate with other devices, the processor being used to perform the method according to any one of claims 1-4.

13. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores instructions that, when executed, cause a computer to perform the method as described in any one of claims 1-4.

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