CN-115885119-B - Control method and device

CN115885119BCN 115885119 BCN115885119 BCN 115885119BCN-115885119-B

Abstract

A control method and a control device relate to the field of control and can be applied to an electric drive system, the electric drive system comprises an oil pump (401), a motor (402), a speed reducer (403) and a shell (404), the motor (402) and the speed reducer (403) are arranged in the shell (404), lubricating oil is stored in the shell (404), and the oil pump (401) is used for pumping the lubricating oil. The method comprises the steps of obtaining a first rotating speed of a motor (402), a second rotating speed of an oil pump (401) and the temperature of lubricating oil in a shell (404), and controlling the rotating speed of the oil pump (401) to be a third rotating speed according to the first rotating speed, the second rotating speed and the temperature. Therefore, the liquid level height of the lubricating oil in the shell (404) and the power of the oil pump under different oil pump rotating speeds can be changed by adjusting the rotating speed of the oil pump (401), so that the assembly efficiency is effectively improved.

Inventors

MA WENWU
CAO YI
REN MAOJIE
ZHANG JINSONG

Assignees

华为数字能源技术有限公司

Dates

Publication Date: 20260505
Application Date: 20201230

Claims (13)

1. A control method, characterized by being applied to an electric drive system including an oil pump, a motor, a speed reducer, and a casing, the motor and the speed reducer being disposed in the casing, lubricating oil being stored in the casing, the oil pump being configured to pump the lubricating oil, the method comprising: acquiring a first rotating speed of the motor, a second rotating speed of the oil pump and the temperature of lubricating oil in the shell; Determining an association relation corresponding to the temperature according to the temperature, wherein the association relation comprises an association relation of motor rotating speed, oil pump rotating speed and loss; Determining a first loss corresponding to the first rotating speed and the second rotating speed and a plurality of second losses corresponding to the first rotating speed in the association relation; And if one of the second losses is smaller than the first loss, adjusting the rotation speed of the oil pump to be a third rotation speed, wherein the third rotation speed is the rotation speed of the oil pump corresponding to the second loss.
2. The method as recited in claim 1, further comprising: And if a plurality of second losses are smaller than the first losses, adjusting the rotation speed of the oil pump to be the third rotation speed, wherein the third rotation speed is the rotation speed of the oil pump corresponding to the lowest loss in the plurality of second losses.
3. The method of claim 1 or 2, wherein the losses include churning losses and oil pump power losses, wherein the churning losses are power losses due to liquid drag experienced by the rotation of the retarder gear in the lubrication oil within the housing.
4. The method of claim 1, wherein the motor speed, the oil pump speed and the losses are continuous functional relationships in the correlation.
5. A control device, characterized by being applied to an electric drive system, the electric drive system including an oil pump, a motor, a speed reducer, and a casing, the motor and the speed reducer being disposed in the casing, lubricating oil being stored in the casing, the oil pump being configured to pump the lubricating oil, the device comprising: the processing unit is used for acquiring the first rotating speed of the motor, the second rotating speed of the oil pump and the temperature of lubricating oil in the shell; The processing unit is further used for determining an association relation corresponding to the temperature according to the temperature, wherein the association relation comprises an association relation of motor rotation speed, oil pump rotation speed and loss; Determining a first loss corresponding to the first rotating speed and the second rotating speed and a plurality of second losses corresponding to the first rotating speed in the association relation; And if one of the second losses is smaller than the first loss, adjusting the rotation speed of the oil pump to be a third rotation speed, wherein the third rotation speed is the rotation speed of the oil pump corresponding to the second loss.
6. The apparatus of claim 5, the processing unit being further specifically configured to: And if a plurality of second losses are smaller than the first losses, adjusting the rotation speed of the oil pump to be the third rotation speed, wherein the third rotation speed is the rotation speed of the oil pump corresponding to the lowest loss in the plurality of second losses.
7. The apparatus of claim 5 or 6, wherein the losses include churning losses and oil pump power losses, wherein the churning losses are power losses due to liquid drag experienced by the rotation of the retarder gear in the lubrication oil within the housing.
8. The apparatus of claim 5, wherein the motor speed, the oil pump speed and the losses are continuous functions in the correlation.
9. A control device comprising a processor for invoking a program in memory to perform the method of any of claims 1-4.
10. A powertrain comprising the control device of any one of claims 5-8, further comprising an inverter, a motor, and a decelerator; the inverter is used for converting direct current into alternating current and transmitting the alternating current to the motor; the motor is used for converting the alternating current into mechanical energy to drive a vehicle to run; the speed reducer is used for converting the output rotating speed of the motor rotating shaft of the motor.
11. A vehicle comprising the powertrain of claim 10 and a power battery for providing dc power to an inverter.
12. A chip comprising a processor and interface circuitry for communicating with other devices, the processor being configured to perform the method of any of claims 1-4.
13. A computer readable storage medium storing instructions that, when executed, cause a computer to perform the method of any one of claims 1-4.

Description

Control method and device Technical Field The present application relates to the field of control, and in particular, to a control method and apparatus. Background The electric drive assembly is a core part of a new energy automobile, and the pursuit of high efficiency of the electric drive assembly has become a mainstream development demand and trend. The efficiency of the electric drive assembly system is improved, the endurance mileage of the whole vehicle can be improved, and the endurance mileage is one of the most important performance indexes of the new energy automobile. At present, an electronic oil pump is generally used for cooling and actively lubricating a motor and a speed reducer, and the electronic oil pump is used for conveying lubricating oil to each friction part of the motor so as to circulate the lubricating oil in a lubricating loop, thereby ensuring that the motor is well cooled and lubricated. However, when the electronic oil pump is used for cooling and lubricating the assembly motor and the speed reducer, the assembly loss is large, and the assembly efficiency is not effectively improved. Disclosure of Invention The embodiment of the application provides a control method and a control device, which can control the rotation speed of an oil pump to be a third rotation speed according to the first rotation speed of a motor, the second rotation speed of the oil pump and the temperature of lubricating oil. Therefore, the oil level height of the lubricating oil in the shell can be actively controlled by adjusting the rotating speed of the oil pump, and the oil level height and the oil pump power in the shell under different rotating speeds of the oil pump are changed, so that the assembly efficiency is effectively improved. In a first aspect, an embodiment of the present application provides a control method, applied to an electric driving system, where the electric driving system includes an oil pump, a motor, a speed reducer, and a casing, the motor and the speed reducer are disposed in the casing, lubricant is stored in the casing, the oil pump is used for pumping the lubricant, the method includes obtaining a first rotational speed of the motor, a second rotational speed of the oil pump, and a temperature of the lubricant in the casing, and controlling the rotational speed of the oil pump to be a third rotational speed according to the first rotational speed, the second rotational speed, and the temperature. Therefore, the embodiment of the application can change the liquid level height of the lubricating oil in the shell and the power of the oil pump under different oil pump rotating speeds by adjusting the rotating speed of the oil pump, thereby effectively improving the assembly efficiency. In one possible implementation manner, the control of the rotation speed of the oil pump to be the third rotation speed according to the first rotation speed, the second rotation speed and the temperature comprises the steps of determining an association relation corresponding to the temperature according to the temperature, wherein the association relation comprises an association relation of the rotation speed of the motor, the rotation speed of the oil pump and the loss, determining first loss corresponding to the first rotation speed and the second rotation speed in the association relation, and controlling the rotation speed of the oil pump to be the third rotation speed according to the first loss and the association relation. Therefore, the embodiment of the application can control the rotation speed of the oil pump through the association relation between the rotation speed of the motor, the rotation speed of the oil pump and the loss, thereby controlling the rotation speed of the oil pump more accurately and effectively improving the efficiency of the assembly. In one possible implementation manner, according to the first loss and the association relation, the rotation speed of the oil pump is controlled to be a third rotation speed, wherein the method comprises the steps of determining a plurality of second losses corresponding to the first rotation speed in the association relation, and adjusting the rotation speed of the oil pump to be the third rotation speed under the condition that one of the second losses is smaller than the first loss, wherein the third rotation speed is the rotation speed of the oil pump corresponding to one of the second losses. According to the embodiment of the application, the rotating speed of the oil pump is adjusted to the rotating speed corresponding to smaller loss, so that the assembly efficiency can be effectively improved. In one possible implementation, the adjusting the rotational speed of the oil pump to be the third rotational speed in the case that one of the second losses is smaller than the first loss includes adjusting the rotational speed of the oil pump to be the third rotational speed in the case that a plurality of the second losses are