Motor temperature control method and device

Abstract

The invention discloses a motor temperature control method and device, motor basic heat dissipation power and motor working loss heat dissipation power of a vehicle are obtained, and the motor basic heat dissipation power of the vehicle is determined according to the current motor temperature and the target motor temperature. And calculating the total heat dissipation power of the motor based on the basic heat dissipation power of the motor and the working loss heat dissipation power of the motor. The motor inlet is connected with the cooling equipment outlet, and cooling liquid conveyed by the cooling equipment to the motor is used for controlling the motor temperature. And obtaining the cooling liquid temperature of the outlet of the cooling equipment based on the heat dissipation power of the cooling equipment. And based on the total heat dissipation power of the motor, the temperature of the cooling liquid at the outlet of the cooling equipment and the temperature rising temperature of the cooling liquid, the target flow of the cooling liquid needed at the current moment is obtained, the motor temperature is controlled based on the cooling liquid of the target flow, and the current temperature of the motor is reduced to the target temperature. According to the method and the device, the accurate target flow of the cooling liquid is obtained and is used for realizing accurate motor temperature control.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a motor temperature control method and device. Background Art

[0002] In a hybrid system, the drive motor is the main power source to realize the vehicle driving function under most working conditions. In practical applications, the temperature control of the motor is very important. For example, when the motor is working under heavy load, a lot of heat will be generated, causing the motor itself to heat up. Excessive temperature will cause the motor to demagnetize and fail to work, and may even cause permanent damage. Therefore, the motor needs to be cooled and controlled.

[0003] In motor cooling control, cooling liquid (such as cooling water or cooling oil, etc.) can be used to control the temperature of the motor, for example, to cool the motor. In specific implementation, it is necessary to first estimate the flow demand of the cooling liquid used for motor temperature control based on the motor temperature. At present, the estimation and control of the flow demand of the cooling liquid are relatively rough, which may cause waste of cooling liquid. Summary of the invention

[0004] In order to solve the above technical problems, the present application provides a motor temperature control method and device, which can finely control the flow rate of cooling liquid required for motor temperature control.

[0005] In order to achieve the above objectives, the technical solutions provided by this application are as follows:

[0006] In a first aspect, the present application provides a motor temperature control method, the method comprising:

[0007] Obtaining the basic heat dissipation power of the motor of the vehicle and the heat dissipation power of the motor working loss; the basic heat dissipation power of the motor is determined by the current temperature of the motor and the target temperature of the motor;

[0008] Calculating the total heat dissipation power of the motor based on the basic heat dissipation power of the motor and the working loss heat dissipation power of the motor;

[0009] Based on the heat dissipation power of the cooling device, the temperature of the cooling liquid at the outlet of the cooling device is obtained; the inlet of the motor is connected to the outlet of the cooling device, and the cooling liquid delivered by the cooling device to the motor is used to achieve temperature control of the motor;

[0010] Based on the total heat dissipation power of the motor, the temperature of the cooling liquid at the outlet of the cooling device, and the heating temperature of the cooling liquid, a target flow rate of the cooling liquid corresponding to the motor at the current moment is obtained, and the temperature of the motor is controlled based on the cooling liquid with the target flow rate, so that the temperature of the cooling liquid is increased from the cooling liquid temperature at the outlet of the cooling device to the heating temperature of the cooling liquid, and the output power is equal to the total heat dissipation power of the motor, so as to reduce the motor from the current temperature of the motor to the target temperature of the motor;

[0011] Wherein, the heating temperature of the cooling liquid is the same as the cooling liquid temperature at the inlet of the cooling device.

[0012] In a second aspect, the present application provides a motor temperature control device, the device comprising:

[0013] A first acquisition unit is used to acquire a basic heat dissipation power of a motor and a heat dissipation power of a motor working loss of a vehicle; the basic heat dissipation power of the motor is determined by a current temperature of the motor and a target temperature of the motor;

[0014] A calculation unit, used for calculating the total heat dissipation power of the motor based on the basic heat dissipation power of the motor and the heat dissipation power of the motor working loss;

[0015] A second acquisition unit is used to acquire the temperature of the cooling liquid at the outlet of the cooling device based on the heat dissipation power of the cooling device; the inlet of the motor is connected to the outlet of the cooling device, and the cooling liquid delivered by the cooling device to the motor is used to achieve temperature control of the motor;

[0016] a third acquisition unit, for acquiring a target flow rate of the cooling liquid corresponding to the motor at a current moment based on the total heat dissipation power of the motor, the temperature of the cooling liquid at the outlet of the cooling device, and the heating temperature of the cooling liquid, so as to control the temperature of the motor based on the cooling liquid of the target flow rate, so that the temperature of the cooling liquid is increased from the temperature of the cooling liquid at the outlet of the cooling device to the heating temperature of the cooling liquid, and the output power is equal to the total heat dissipation power of the motor, so as to reduce the motor from the current temperature of the motor to the target temperature of the motor;

[0017] Wherein, the heating temperature of the cooling liquid is the same as the cooling liquid temperature at the inlet of the cooling device.

[0018] In a third aspect, the present application provides an electronic device, including:

[0019] one or more processors;

[0020] a storage device having one or more programs stored thereon,

[0021] When the one or more programs are executed by the one or more processors, the one or more processors implement any of the motor temperature control methods.

[0022] In a fourth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements any of the motor temperature control methods described above.

[0023] Through the above technical solution, it can be seen that the present application has the following beneficial effects:

[0024] The present application provides a motor temperature control method and device, firstly obtaining the basic heat dissipation power of the motor of the vehicle and the heat dissipation power of the motor working loss. Among them, the basic heat dissipation power of the motor of the vehicle is determined by the current temperature of the motor and the target temperature of the motor. The total heat dissipation power of the motor is calculated based on the basic heat dissipation power of the motor and the heat dissipation power of the motor working loss. The inlet of the motor is connected to the outlet of the cooling device, and the cooling liquid delivered by the cooling device to the motor is used to realize the temperature control of the motor. In order to realize the control of the motor temperature, such as cooling and cooling, the total heat dissipation power of the motor represents the heat that the motor needs to dissipate, that is, the motor needs to be temperature-controlled by the cooling liquid so that the power corresponding to the heat dissipated by the motor is the total heat dissipation power of the motor. Then, based on the heat dissipation power of the cooling device, the temperature of the cooling liquid at the outlet of the cooling device is obtained, and based on the total heat dissipation power of the motor, the temperature of the cooling liquid at the outlet of the cooling device and the heating temperature of the cooling liquid, the target flow rate of the cooling liquid corresponding to the motor at the current moment is obtained, and the temperature of the motor is controlled by the cooling liquid based on the target flow rate, so that the temperature of the cooling liquid is increased from the temperature of the cooling liquid at the outlet of the cooling device to the heating temperature of the cooling liquid, and the output power is equal to the total heat dissipation power of the motor. In this way, the motor can be reduced from the current temperature of the motor to the target temperature of the motor. The heating temperature of the cooling liquid is set to be the same as the cooling liquid temperature at the inlet of the cooling device. It can be seen that the present application obtains a more accurate target flow rate of the cooling liquid at the current moment, which is not an estimated value, so that the cooling liquid based on the target flow rate has a better control effect on the temperature control of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 A flow chart of a motor temperature control method provided in an embodiment of the present application;

[0027] Figure 2 A schematic diagram of the flow of motor cooling oil provided in an embodiment of the present application;

[0028] Figure 3a A schematic diagram of motor temperature control provided in an embodiment of the present application;

[0029] Figure 3b A schematic diagram of a motor temperature control framework provided in an embodiment of the present application;

[0030] Figure 4 A schematic diagram of the structure of a motor temperature control device provided in an embodiment of the present application;

[0031] Figure 5 A schematic diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0032] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the embodiments of the present application are further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0033] In order to facilitate the understanding and explanation of the technical solutions provided by the embodiments of the present application, the background technology involved in the embodiments of the present application is first introduced.

[0034] In a hybrid system, the drive motor is the main power source and realizes the vehicle driving function under most working conditions. The drive motor can be an oil-cooled motor or a water-cooled motor, which can be integrated into the vehicle's hybrid transmission. In practical applications, the temperature control of the motor is very important. For example, when the motor is working under heavy load, a lot of heat will be generated, causing the motor itself to heat up. Excessive temperature will cause the motor to demagnetize and fail to work, and may even cause permanent damage. Therefore, the motor needs to be cooled and controlled.

[0035] In motor cooling control, cooling liquid can be used to control the temperature of the motor, for example, to cool the motor. When the motor is an oil-cooled motor, the cooling liquid is cooling oil, and the temperature of the motor is controlled by the cooling oil. When the motor is a water-cooled motor, the cooling liquid is cooling water, and the temperature of the motor is controlled by the cooling water. In specific implementation, it is necessary to first estimate the flow demand of the cooling liquid used for motor temperature control based on the motor temperature. At present, the estimation and control of the flow demand of the cooling liquid are relatively extensive. For example, when the motor temperature is high, the flow rate of the cooling liquid is increased, and when the motor temperature is reduced, the flow rate of the cooling liquid is reduced. However, the increased or reduced flow rate of the cooling liquid is obtained based on manual experience, which is not accurate and may cause waste of cooling liquid.

[0036] Based on this, the present application provides a motor temperature control method and device, first obtaining the basic heat dissipation power of the motor of the vehicle and the heat dissipation power of the motor working loss. Among them, the basic heat dissipation power of the motor of the vehicle is determined by the current temperature of the motor and the target temperature of the motor. The total heat dissipation power of the motor is calculated based on the basic heat dissipation power of the motor and the heat dissipation power of the motor working loss. The inlet of the motor is connected to the outlet of the cooling device, and the cooling liquid delivered by the cooling device to the motor is used to achieve the temperature control of the motor. In order to achieve the control of the motor temperature, such as cooling and cooling, the total heat dissipation power of the motor represents the heat that the motor needs to dissipate, that is, the motor needs to be temperature controlled by the cooling liquid so that the power corresponding to the heat dissipated by the motor is the total heat dissipation power of the motor. Further, based on the heat dissipation power of the cooling device, the temperature of the cooling liquid at the outlet of the cooling device is obtained, and based on the total heat dissipation power of the motor, the temperature of the cooling liquid at the outlet of the cooling device and the heating temperature of the cooling liquid, the target flow rate of the cooling liquid corresponding to the motor at the current moment is obtained, and the temperature of the motor is controlled by the cooling liquid based on the target flow rate, so that the temperature of the cooling liquid is increased from the temperature of the cooling liquid at the outlet of the cooling device to the heating temperature of the cooling liquid, and the output power is equal to the total heat dissipation power of the motor. In this way, the motor can be reduced from the current temperature of the motor to the target temperature of the motor. The heating temperature of the cooling liquid is set to be the same as the cooling liquid temperature at the inlet of the cooling device. It can be seen that the present application obtains a more accurate target flow rate of the cooling liquid at the current moment, which is not an estimated value, so that the control effect of the temperature control of the motor based on the cooling liquid of the target flow rate is better.

[0037] It is understandable that the defects in the above solutions are the results obtained by the applicant after practice and careful research. Therefore, the discovery process of the above problems and the solutions proposed in the embodiments of the present application for the above problems below should be the contributions made by the applicant to the embodiments of the present application during the application process.

[0038] To facilitate understanding of the present application, a motor temperature control method provided in an embodiment of the present application is described below in conjunction with the accompanying drawings.

[0039] See also Figure 1 , which is a flow chart of a motor temperature control method provided in an embodiment of the present application. The method can be applied to a vehicle's automatic transmission control unit (TCU), where the TCU is integrated into a transmission. For example, the transmission is a hybrid transmission. Figure 1 As shown, the method may include S101-S104:

[0040] S101: Obtaining a basic motor heat dissipation power and a motor working loss heat dissipation power of a vehicle; the basic motor heat dissipation power is determined by a current motor temperature and a target motor temperature.

[0041] The hybrid transmission may be integrated with an oil-cooled motor and / or a water-cooled motor, which is used to provide the main power source for the vehicle. The TCU executes the motor temperature control method provided in the embodiment of the present application to accurately control the temperature of the motor in the hybrid transmission, for example, to perform cooling control.

[0042] In practical applications, the temperature of the motor is adjusted based on the cooling liquid. The cooling liquid used in oil-cooled motors is cooling oil, and the cooling liquid used in water-cooled motors is cooling water, and the cooling liquid is stored in a corresponding device. When the cooling liquid is delivered from the pump to the motor, a cooling device is required. The cooling device is used to control the temperature of the cooling liquid output by the pump, for example, to reduce the temperature of the cooling liquid to deliver low-temperature cooling liquid to the motor to achieve temperature control of the motor. When the motor is an oil-cooled motor, the cooling liquid used is cooling oil, the corresponding cooling device is an oil cooler, and the device for storing cooling oil can be an oil pump; when the motor is a water-cooled motor, the cooling liquid used is cooling water, the corresponding cooling device is a water cooler, and the device for storing cooling water can be a water pump. The embodiments of this application will be described later using the motor as an oil-cooled motor, the cooling device as an oil cooler, the cooling liquid as cooling oil, and the device for storing cooling oil as an oil pump as an example, but are not limited to this.

[0043] The following first describes a process of regulating the motor temperature based on a cooling liquid (such as cooling oil).

[0044] See also Figure 2 , Figure 2 A schematic diagram of the flow of motor cooling oil provided in an embodiment of the present application. As an optional example, the motor in the hybrid transmission may include a P1 motor and a P3 motor. Both the P1 motor and the P3 motor are oil-cooled motors. The oil pump includes a mechanical oil pump MOP and / or an electronic oil pump EOP. Figure 2 As shown, the mechanical oil pump MOP and / or the electronic oil pump EOP outputs cooling oil for cooling the motor. At this time, the temperature of the cooling oil is still relatively high, and the purpose of cooling the motor temperature cannot be achieved. Based on this, the mechanical oil pump MOP and / or the electronic oil pump EOP outputs cooling oil to the oil cooler to reduce the temperature of the cooling oil through the oil cooler. Specifically, in the oil cooler, cooling air is used to cool the cooling oil, and the cooling air is transmitted from outside the vehicle to the cooler by a fan in the vehicle. The oil cooler outputs cooling oil cooled to a suitable temperature, and the cooling oil is further delivered to the P1 motor and the P3 motor after passing through the solenoid valve to adjust the temperature of the P1 motor and the P3 motor, such as cooling and cooling.

[0045] As an alternative example, Figure 2As shown, temperature sensors are provided in the P1 motor and the P3 motor to collect the current temperature of the P1 motor and the P3 motor. An oil temperature sensor is also provided near the oil pump to collect the oil temperature of the oil pan. In addition, if the clutch in the vehicle also needs to be cooled, the cooled cooling oil can also be delivered to the clutch to control the temperature of the clutch.

[0046] Based on the above content, the motor temperature control method provided in the embodiment of the present application can determine a more accurate flow rate of the cooling liquid used to adjust the temperature of the motor, so as to more accurately control the temperature of the motor.

[0047] In a specific implementation, when the motor in the vehicle starts to work and the activation conditions of the motor temperature control are met, the motor can be temperature controlled, such as cooling control. The activation conditions of the motor temperature control may include one or more of the following:

[0048] The adaptive cruise control ACC and KL15 are hard-wired high, the motors (such as P1 motor and P3 motor) start working, there is no fault code inside the TCU, and the devices storing cooling liquid (such as MOP and / or EOP storing oil) operate normally.

[0049] If the motor starts working and meets the above-mentioned activation conditions for the motor temperature control, the flow rate of the cooling liquid used to adjust the motor temperature can be determined based on the motor temperature control method provided in the embodiment of the present application to control the temperature of the motor, such as cooling it down.

[0050] First, obtain the basic heat dissipation power of the motor and the working loss heat dissipation power of the motor of the vehicle. The basic heat dissipation power of the motor is determined by the current temperature of the motor and the target temperature of the motor, and the current temperature of the motor is greater than the target temperature of the motor. The basic heat dissipation power of the motor represents the power dissipated by reducing the temperature of the motor from the current temperature of the motor to the target temperature of the motor, and can also represent the heat taken away by the motor when the motor is reduced from the current temperature of the motor to the target temperature of the motor. Among them, the target temperature of the motor can be set. It can be seen that when the temperature of the motor is controlled, the motor is in a working state. The operation of the motor will generate the working loss heat dissipation power of the motor. The working loss heat dissipation power of the motor represents the power dissipated in the form of heat when the motor is working.

[0051] The basic heat dissipation power of the motor and the heat dissipation power of the motor working loss represent the total heat dissipation demand of the motor. The temperature of the motor needs to be adjusted by cooling liquid to meet the heat dissipation demand of the motor.

[0052] In a possible implementation, the embodiment of the present application provides a specific implementation method for obtaining the basic heat dissipation power of the motor and the heat dissipation power of the motor working loss of the vehicle, including A1-A2:

[0053] A1: Set the motor target temperature and obtain the basic motor heat dissipation power of the vehicle based on the motor target temperature, current motor temperature, motor specific heat capacity, and motor mass.

[0054] The current temperature of the motor can be acquired by the temperature sensor installed in the motor. Different motors (such as P1 motor and P3 motor) can be installed with corresponding temperature sensors. The motor target temperature is the temperature that the motor is to reach after the motor is temperature-controlled based on the cooling liquid. It is an expected temperature value that can be set. Usually, the current temperature of the motor is greater than the motor target temperature. In practical applications, the motor target temperatures of different motors can be the same or different, which is not limited here.

[0055] As an optional example, the difference between the current motor temperature and the target motor temperature is calculated, and the product of the motor specific heat capacity, the motor mass and the difference is used as the basic motor heat dissipation power of the vehicle. Based on this, the present application provides a basic motor heat dissipation power P base The calculation formula is as follows:

[0056] P base =C m M m (T mActual -T mTarget )

[0057] Among them, C m is the specific heat capacity of the motor, in J / (kg*K), M m is the motor mass, in kg, T mActual The current temperature of the motor, in K, T mTarget is the motor target temperature, in K.

[0058] It is understandable that the current temperature of the motor at each moment can be obtained, and the target temperature of the motor at each moment can be set, so the basic heat dissipation power of the motor of the vehicle at each moment can be obtained.

[0059] A2: Based on the electric power and mechanical power of the motor, the working loss heat dissipation power of the motor of the vehicle is obtained; the electric power of the motor is determined by the power supply current and the power supply voltage of the motor, and the mechanical power of the motor is determined by the motor output torque and the motor speed of the motor.

[0060] The power provided by the vehicle to the motor is the electrical power, and the power of the motor to do work is the mechanical power. The electrical power of the motor is the product of the motor supply current and the motor supply voltage, and the mechanical power of the motor is the product of the motor output torque and the motor speed.

[0061] As an optional example, the difference between the motor's electrical power and the motor's mechanical power is determined as the motor's working loss heat dissipation power of the vehicle, that is, the power lost by the motor in the form of heat dissipation. Based on this, the present application provides a motor working loss heat dissipation power P Loss The calculation formula is as follows:

[0062] P Loss =I m U m -Torq m Sd m

[0063] Among them, I m The motor power supply current, in A, U m The motor supply voltage is in V, Torq m is the motor output torque, in Nm, Spd m is the motor speed in rpm. Then, I m U m is the electrical power of the motor, Torq m Sd m is the mechanical power of the motor.

[0064] It can be understood that if the electrical power and mechanical power of the motor at each moment can be obtained, then the motor working loss and heat dissipation power of the vehicle at each moment can be obtained.

[0065] See also Figure 3a , Figure 3a A schematic diagram of motor temperature control provided in an embodiment of the present application. Figure 3a The oil pump, cooling oil, and oil cooler are used as examples for explanation. Figure 3a As shown, when the motors in the vehicle include a P1 motor and a P3 motor, the P1 motor and the P3 motor may have different flow requirements for cooling liquid. In this case, the basic motor heat dissipation power (characterizing the basic heat dissipation power requirement) and the motor working loss heat dissipation power of the P1 motor, as well as the basic motor heat dissipation power (characterizing the basic heat dissipation power requirement) and the motor working loss heat dissipation power of the P3 motor can be obtained based on the A1-A2 method at the same time to calculate the cooling liquid flow required for each motor.

[0066] S102: Calculating the total heat dissipation power of the motor based on the basic heat dissipation power of the motor and the heat dissipation power of the motor working loss.

[0067] As an optional example, the sum of the basic heat dissipation power of the motor and the heat dissipation power of the motor working loss is taken as the total heat dissipation power of the motor, that is, the total heat dissipation power of the motor is P base +P LossThe total heat dissipation power of the motor indicates the total heat that the motor needs to dissipate, that is, the total heat that needs to be taken away when cooling liquid is needed for temperature control. It can be understood that based on the basic heat dissipation power of the motor and the heat dissipation power of the motor working loss at each moment, the total heat dissipation power of the motor at each moment can be calculated.

[0068] like Figure 3a As shown, the total motor heat dissipation power corresponding to the P1 motor is calculated based on the sum of the motor basic heat dissipation power and the motor working loss heat dissipation power of the P1 motor. The total motor heat dissipation power corresponding to the P3 motor is calculated based on the sum of the motor basic heat dissipation power and the motor working loss heat dissipation power of the P3 motor.

[0069] S103: Based on the heat dissipation power of the cooling device, the temperature of the cooling liquid at the outlet of the cooling device is obtained; the inlet of the motor is connected to the outlet of the cooling device, and the cooling liquid delivered by the cooling device to the motor is used to achieve temperature control of the motor.

[0070] The cooling device is used to cool the cooling liquid entering the cooling device, and the temperature of the cooling liquid at the cooling device outlet is lower than the temperature of the cooling liquid at the cooling device inlet. The cooling liquid at the cooling device outlet is lower in temperature, and the temperature of the motor can be adjusted based on the lower temperature of the cooling liquid, for example, the temperature of the motor can be reduced. Since the inlet of the motor is connected to the outlet of the cooling device, the temperature of the cooling liquid at the cooling device outlet is the same as the temperature of the cooling liquid at the inlet of the motor. When the cooling liquid is cooling oil, the temperature of the cooling liquid at the inlet of the motor is Figure 3a The motor inlet oil temperature is .

[0071] The cooling liquid temperature at the cooling device outlet is used to subsequently determine the cooling liquid flow rate required by the motor. It is understandable that after the cooling liquid with a lower temperature is used to cool the motor, the temperature of the motor will decrease, and the temperature of the cooling liquid will increase (the temperature after the increase is set to be certain), and the dissipated power is the total heat dissipation power of the motor.

[0072] In practical applications, the temperature of the cooling liquid at the outlet of the cooling device at each moment can be obtained. The temperature of the cooling liquid at the outlet of the cooling device is related to the cooling capacity of the cooling device, and the temperature of the cooling liquid at the outlet of the cooling device can be adjusted by adjusting the cooling capacity of the cooling device. It can be seen that when the cooling capacity of the cooling device is stronger, the temperature of the cooling liquid at the outlet of the cooling device is lower. When the dissipated power is determined as the total heat dissipation power of the motor and the temperature of the cooling liquid after cooling the motor is determined, the lower the temperature of the cooling liquid at the outlet of the cooling device, the less the flow rate of the cooling liquid is required.

[0073] In a possible implementation, the embodiment of the present application provides a specific implementation method for obtaining the cooling liquid temperature at the outlet of the cooling device based on the heat dissipation power of the cooling device, including B1-B2:

[0074] B1: Obtain the heat exchange power between the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid; the heat exchange power between the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid are both used to characterize the heat dissipation power of the cooling device.

[0075] The cooling device can achieve heat exchange between two fluid media with a certain temperature difference (such as a high-temperature cooling liquid and a low-temperature cooling air), thereby achieving the purpose of reducing the temperature of the cooling liquid. The cooling air can be cooled by the fan in the vehicle and then transmitted to the cooling device.

[0076] During the heat exchange process, heat exchange power between the cooling liquid and the cooling air and heat dissipation power of the cooling liquid are generated. The heat exchange power between the cooling liquid and the cooling air is the heat dissipation power generated by heat exchange between the cooling liquid with a higher temperature in the cooling device (specifically, the temperature of the cooling liquid at the inlet of the cooling device) and the cooling air with a lower temperature (specifically, the ambient temperature). The heat dissipation power of the cooling liquid is the heat dissipation power generated when the temperature of the cooling liquid is reduced from the cooling liquid temperature at the inlet of the cooling device to the cooling liquid temperature at the outlet of the cooling device. Reducing the cooling liquid temperature at the inlet of the cooling device to the cooling liquid temperature at the outlet of the cooling device is achieved by heat exchange between the cooling liquid in the cooling device and the cooling air.

[0077] As an optional example, obtaining the heat exchange power between the cooling liquid and the cooling air includes:

[0078] The heat exchange power between the cooling liquid and the cooling air is obtained based on the convective heat transfer coefficient of the cooling device, the heat exchange area of ​​the cooling device, the cooling liquid temperature at the inlet of the cooling device and the ambient temperature; wherein the convective heat transfer coefficient of the cooling device is related to the speed of the vehicle and the opening degree of the fan in the vehicle, and the fan is used to transport cooling air to the vehicle to reduce the temperature of the cooling liquid.

[0079] Generally, the temperature of the cooling liquid at the inlet of the cooling device is higher than the ambient temperature. For example, the difference between the temperature of the cooling liquid at the inlet of the cooling device and the ambient temperature is first calculated. Then, the product of the convective heat transfer coefficient of the cooling device, the heat exchange area of ​​the cooling device and the difference is used as the heat exchange power between the cooling liquid and the cooling air.

[0080] Based on this, when taking the oil cooler and cooling oil as an example, the present application provides the heat exchange power of cooling liquid and cooling air. The calculation formula is as follows:

[0081]

[0082] Among them, h Oil is the oil cooler convection heat transfer coefficient (i.e., an example of the convection heat transfer coefficient of the cooling device), in W / (m2 *K), A Oil is the heat exchange area of ​​the oil cooler (i.e. an example of the heat exchange area of ​​the cooling equipment), in m 2 , T OilIn , T Air are the oil cooler inlet temperature (i.e. an example of the temperature of the cooling liquid at the inlet of the cooling device) and the ambient temperature, in K, respectively.

[0083] It should be noted that “oil” in the formula parameters described as examples in this application can be replaced with “cooling liquid”.

[0084] It is understandable that since the cooling device cools the cooling liquid by cooling the air, when the vehicle speed and the opening degree of the fan in the vehicle are determined, the air flow rate of the cooling air is determined, and the convective heat transfer coefficient of the cooling device is determined. For example, the cooling capacity of the cooling device can be adjusted by adjusting the convective heat transfer coefficient of the cooling device.

[0085] As an optional example, obtaining the heat dissipation power of the cooling liquid includes:

[0086] The heat dissipation power of the cooling liquid is obtained based on the cooling liquid temperature at the cooling device inlet, the cooling liquid temperature at the cooling device outlet, the cooling liquid specific heat capacity, the cooling liquid density, and the total flow rate of the cooling liquid passing through the cooling device at the last moment.

[0087] For example, the difference between the cooling liquid temperature at the inlet of the cooling device and the cooling liquid temperature at the outlet of the cooling device is calculated, and then the product of the cooling liquid specific heat capacity, cooling liquid density, the total flow rate of cooling liquid passing through the cooling device at the last moment and the difference is used as the heat dissipation power of the cooling liquid.

[0088] Based on this, when taking the oil cooler and cooling oil as an example, the present application provides the heat dissipation power of the cooling liquid The calculation formula is as follows:

[0089]

[0090] Among them, C Oil is the specific heat capacity of oil (an example of the specific heat capacity of cooling liquid), in J / (kg*k), ρ Oil is the oil density (example of cooling liquid density), in kg / m 3 ,Q OilTotal The total flow rate of cooling oil passing through the oil cooler at the last moment (an example of the total flow rate of cooling liquid passing through the cooling device at the last moment), in m 3 / s. T OilOut is the oil temperature at the outlet of the oil cooler (an example of the temperature of the cooling liquid at the outlet of the cooling device), in K.

[0091] It can be understood that when the P1 motor, P3 motor and clutch in the vehicle all need cooling liquid for temperature control, the total flow of cooling liquid passing through the cooling device at the last moment is the sum of the total flow of motor cooling at the last moment and the flow of cooling liquid required by the target device of the vehicle (such as the clutch) at the last moment. The total flow of motor cooling at the last moment is the sum of the flow of cooling liquid required by the P1 motor at the last moment and the flow of cooling liquid required by the P3 motor at the last moment.

[0092] B2: Based on the conservation relationship between the heat exchange power between the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid, the cooling liquid temperature at the cooling device outlet is obtained.

[0093] It can be seen that the heat exchange power between the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid are both used to characterize the heat dissipation power of the cooling device. The heat dissipation power of the cooling device can be expressed by the heat exchange power between the cooling liquid and the cooling air, or by the heat dissipation power of the cooling liquid. That is, the heat dissipation power of the cooling device is equal to the heat exchange power between the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid, and is also equal to the heat dissipation power of the cooling liquid. This is attributed to the conservation relationship between the heat exchange power between the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid.

[0094] The conservation relationship between the heat exchange power of the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid indicates that the heat exchange power of the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid are the same. Based on this, the cooling liquid temperature at the cooling device outlet can be calculated.

[0095] When the cooling device is an oil cooler, the cooling liquid temperature at the inlet of the cooling device is the oil temperature at the inlet of the oil cooler, and the oil temperature at the inlet of the oil cooler can be considered as the oil temperature of the oil pan. Figure 3a As shown, the cooling liquid temperature at the cooling device outlet (i.e., the same as the cooling liquid temperature at the motor inlet, such as the motor inlet oil temperature) is related to the ambient temperature, the cooling liquid temperature at the cooling device inlet (such as the oil pan oil temperature), the fan opening, the vehicle speed, and the total cooling liquid flow through the cooling device at the last moment (such as the total cooling oil flow through the oil cooler at the last moment).

[0096] S104: Based on the total heat dissipation power of the motor, the cooling liquid temperature at the outlet of the cooling device and the heating temperature of the cooling liquid, obtain the target flow rate of the cooling liquid corresponding to the motor at the current moment, and control the temperature of the motor with the cooling liquid based on the target flow rate, so that the temperature of the cooling liquid increases from the cooling liquid temperature at the outlet of the cooling device to the heating temperature of the cooling liquid, and the output power is equal to the total heat dissipation power of the motor, so as to reduce the motor from the current temperature of the motor to the target temperature of the motor.

[0097] After knowing the total heat dissipation power of the motor, it is possible to know the total heat that needs to be dissipated by the motor when the cooling liquid is used to control the temperature of the motor. After the cooling liquid takes away the heat to cool the motor, the temperature of the cooling liquid rises from the cooling liquid temperature at the outlet of the cooling device to the heating temperature of the cooling liquid, and its output power should be equal to the total heat dissipation power of the motor. The heating temperature of the cooling liquid is fixed, and can be the cooling liquid temperature at the inlet of the cooling device (for example, if it is an oil cooler, this temperature is the oil temperature of the oil pan). Since the above-mentioned temperature control is realized based on a certain flow rate of cooling liquid, in order to achieve the above-mentioned temperature control result, the size of the target flow rate of the cooling liquid corresponding to the motor at the current moment can be determined.

[0098] In addition, after the motor temperature is controlled by the cooling liquid based on the target flow rate, the heat corresponding to the total heat dissipation power of the motor is dissipated, which will reduce the motor temperature from the current motor temperature to the motor target temperature.

[0099] The temperature of the cooling liquid is the same as the temperature of the cooling liquid at the inlet of the cooling device. When the cooling device is an oil cooler, the temperature of the cooling liquid at the inlet of the cooling device is the temperature at the inlet of the oil cooler, that is, the oil temperature of the oil pan.

[0100] The target flow rate of cooling liquid corresponding to the motor at the current moment is the flow rate of cooling liquid required by the motor at the current moment. It can be understood that the motor temperature control method provided in the embodiment of the present application can calculate the flow rate of cooling liquid required by the motor at each moment, and it is relatively accurate.

[0101] In a possible implementation, the embodiment of the present application provides a specific implementation method for obtaining the target flow rate of the cooling liquid corresponding to the motor at the current moment based on the total heat dissipation power of the motor, the cooling liquid temperature at the outlet of the cooling device, and the heating temperature of the cooling liquid, including C1-C2:

[0102] C1: Calculate the motor cooling convection heat transfer coefficient based on the total heat dissipation power of the motor, the motor cooling heat exchange area, the cooling liquid temperature at the cooling device outlet, and the heating temperature of the cooling liquid.

[0103] As an optional example, the difference between the rising temperature of the cooling liquid and the cooling liquid temperature at the outlet of the cooling device is first calculated, and then the product of the difference and the motor cooling heat exchange area is calculated. The quotient of the total heat dissipation power of the motor and the product is the motor cooling convection heat transfer coefficient.

[0104] Based on this, this application provides a calculation formula for the motor cooling convection heat transfer coefficient as follows:

[0105] P base +P Loss =h m A m (TOilActual -T OilOut )

[0106] Among them, h m is the motor cooling convection heat transfer coefficient, in W / (m 2 *K), A m is the motor cooling heat exchange area, in m 2 . T OilActual is the heating temperature of the cooling oil (an example of the heating temperature of the cooling liquid).

[0107] C2: Based on the calibration relationship between the motor cooling convection heat transfer coefficient and the cooling liquid flow rate, the target flow rate of the cooling liquid at the current moment corresponding to the motor cooling convection heat transfer coefficient is obtained.

[0108] It can be understood that the motor cooling convection heat transfer coefficient is related to the flow rate of the cooling liquid. The higher the flow rate of the cooling liquid, the greater the motor cooling convection heat transfer coefficient.

[0109] As an optional example, a calibration relationship between the motor cooling convection heat transfer coefficient and the cooling liquid flow rate is predetermined. The calibration relationship can be recorded in a table, in which the corresponding relationship between the motor cooling convection heat transfer coefficient and the cooling liquid flow rate is recorded, and the corresponding relationship is obtained through actual vehicle test calibration.

[0110] The cooling liquid flow is denoted as Q OilCooling , unit is m 3 / s. The calibration relationship between the motor cooling convection heat transfer coefficient and the cooling liquid flow rate is expressed as:

[0111] h m ∝Q OilCooling

[0112] Then, after determining the motor cooling convection heat transfer coefficient at the current moment, the target flow rate of the cooling liquid at the current moment can be determined according to the corresponding relationship by looking up the table.

[0113] Based on the above content, the motor temperature control method provided in the embodiment of the present application further includes the following steps D1-D3:

[0114] D1: Based on the target flow rate of cooling liquid corresponding to each motor at the current moment, the total cooling flow rate of the motor at the current moment is obtained; the total cooling flow rate of the motor at the current moment and the cooling flow rate corresponding to the target device of the vehicle constitute the total cooling liquid flow rate at the current moment.

[0115] It is understandable that the working conditions of each motor are different, and the working parameters of each motor are different. Taking the P1 motor and the P3 motor as an example, when the P1 motor is working, the P3 motor may not be working. The current, voltage, etc. of the two motors may be different when they are working, which affects the total heat dissipation power of the P1 motor and the P3 motor. In this way, the target flow rate of the cooling liquid corresponding to the P1 motor at the current moment and the target flow rate of the cooling liquid corresponding to the P3 motor at the current moment are usually different.

[0116] Based on this, the target flow rate of cooling liquid at the current moment corresponding to each motor in the vehicle that needs temperature control can be obtained, and the total flow rate of motor cooling at the current moment can be obtained by summing them up. Figure 3a As shown, the total motor cooling flow at the current moment may be the sum of the target flow of the cooling liquid corresponding to the P1 motor at the current moment and the obtained target flow of the cooling liquid corresponding to the P3 motor at the current moment.

[0117] In addition, the vehicle target device may also require cooling liquid for temperature control. For example, the vehicle target device is a clutch. The cooling flow rate corresponding to the vehicle target device is determined, usually a constant value, and is determined according to actual conditions. The sum of the total motor cooling flow rate at the current moment and the cooling flow rate corresponding to the vehicle target device can be determined as the total cooling liquid flow rate at the current moment.

[0118] The total motor cooling flow at the current moment is expressed as Q OilTotal , the total flow rate of cooling liquid at the current moment is expressed as Q OilCooling , the relationship between the two is expressed as:

[0119] Q OilTotal ∝Q OilCooling

[0120] It can be seen that Q OilTotal The sum of the cooling flow rates corresponding to the target equipment in the vehicle is Q OilCooling It should be understood that the "oil" in the parameter is used to represent cooling oil, which is only an example of cooling liquid and can be replaced by cooling liquid.

[0121] Based on this, the device storing the cooling liquid can be controlled to deliver the required flow rate (i.e. the total flow rate of the cooling liquid at the current moment) of the cooling liquid to control the temperature of the motor and the target device in the vehicle. Figure 3a As shown, when the cooling liquid is cooling oil, the device storing the cooling liquid is MOP and / or EOP. The flow demand of MOP and / or EOP is the total flow of the cooling liquid at the current moment.

[0122] It can be understood that the total cooling liquid flow rate at the current moment calculated in this step can be used to calculate the cooling liquid temperature at the cooling device outlet (ie, the cooling liquid temperature at the motor inlet) at the next moment.

[0123] D2: Based on the total motor cooling flow at the current moment, determine the control ratio of the valve corresponding to each motor; the motor is connected to the cooling device through the valve.

[0124] like Figure 2 As shown, the motor is connected to the cooling device through a valve, and each motor can be configured with a valve to control the delivery of cooling liquid to the motor. After the target flow rate of the cooling liquid corresponding to the motor at the current moment is determined, the control ratio of the valve corresponding to each motor can be determined based on the total cooling flow rate of the motor at the current moment and the target flow rate of the cooling liquid corresponding to each motor at the current moment. For example, when the target flow rates of the cooling liquid corresponding to the P1 motor and the P3 motor at the current moment are the same, the control ratios of the valves corresponding to the P1 motor and the P3 motor are each one-half. The sum of the control ratios of the valves corresponding to each motor is 1.

[0125] D3: Determine the opening of each valve based on the control ratio of each valve.

[0126] As an optional example, there is a corresponding relationship between the control ratio of the valve and the opening of the valve, and the corresponding relationship can be recorded in a table. When the control ratio of the valve is determined, the opening of the valve can be obtained by looking up the table.

[0127] For example, the valve may be a solenoid valve. Figure 3a As shown, when the valve is a solenoid valve, the valve opening of the solenoid valve can be controlled by the current of the solenoid valve. Specifically, based on the control ratio of each solenoid valve, the control current of each solenoid valve is calculated to control the opening of each solenoid valve by the control current of each solenoid valve. That is, there is a corresponding relationship between the control ratio of the solenoid valve and the control current of the solenoid valve. After determining the control ratio of the solenoid valve, the control current of the solenoid valve can be determined according to the corresponding relationship. The control current of the solenoid valve can control the opening of the solenoid valve, and there is also a corresponding relationship between the two.

[0128] See also Figure 3b , Figure 3b A schematic diagram of a motor temperature control framework provided in an embodiment of the present application. Figure 3bAs shown, taking the cooling liquid as cooling oil as an example, when the motor starts working and meets the activation conditions of the motor temperature control, the total heat dissipation power of the motor and the motor inlet oil temperature at the current moment can be calculated. Then, the total motor cooling flow at the current moment can be calculated based on the total heat dissipation power of the motor and the motor inlet oil temperature at the current moment. Further, the target total flow of the oil pump at the current moment is obtained based on the total cooling flow of the motor at the current moment and the corresponding cooling flow of the target device of the vehicle, so as to control the oil pump to output the cooling oil of the target total flow of the oil pump. On the other hand, after obtaining the total cooling flow of the motor at the current moment, the solenoid valve control ratio of the solenoid valve corresponding to each motor can be determined in combination with the target flow of the cooling liquid corresponding to each motor at the current moment, and then the opening of the solenoid valve can be controlled. On the other hand, after obtaining the target total flow of the oil pump at the current moment, this value can be applied to the calculation of the motor inlet oil temperature at the next moment.

[0129] In practical applications, the motor temperature control method provided in the embodiment of the present application can realize the two-way control of heating and cooling the motor temperature. For example, by setting the basic heat dissipation power demand of a negative value under low temperature conditions (i.e. setting the motor target temperature so that the motor basic heat dissipation power is a negative value), the motor temperature can be increased by the motor working loss heat dissipation power, so that the motor can quickly reach the function of the efficient working temperature range. For example, if the motor target temperature is set so that the motor basic heat dissipation power is -5kw, and the motor working loss heat dissipation power is 15kw, then the total heat dissipation power of the motor is 10kw. Therefore, only 10kw of heat from the motor needs to be dissipated, and 5kw of heat is used for motor heating, so that the motor can quickly reach the efficient working temperature range. In addition, the basic heat dissipation power demand under high temperature conditions of the motor can be increased, thereby increasing the overall cooling flow demand, and realizing the rapid cooling and high temperature protection functions of the motor.

[0130] In addition, the motor temperature control method provided by the embodiment of the present application can also reduce the energy loss of the storage device (such as an oil pump) of the cooling liquid. By calculating the motor cooling flow demand at each moment and adjusting the precise flow control of the storage device (such as MOP and EOP) of the cooling liquid in real time, unnecessary energy loss can be reduced and the overall energy efficiency can be improved. It is understandable that each moment in the embodiment of the present application can be determined according to the actual situation, for example, it can be every second, or every minute, which is not limited here.

[0131] Based on the relevant contents of S101-S104 above, it can be known that the embodiment of the present application provides a more accurate motor temperature control method, which can be used to control the real-time cooling of the motor of the hybrid transmission. The motor cooling demand is mainly estimated based on the basic heat dissipation power demand of the motor and the heat dissipation power demand of the motor working loss, and the total flow demand of the motor cooling is estimated in combination with information such as ambient temperature, fan opening, and vehicle speed. Based on the cooling flow demand of each motor and the total cooling flow demand of the motor, the valves for controlling the flow and the device for storing the cooling liquid are controlled respectively. In this way, the real-time heat generation of the motor is taken into account, the cooling flow demand of the motor can be calculated more accurately, the cooling flow control of the motor is more refined, and the precise control of the motor cooling is achieved, thereby reducing the load of the storage device for the cooling liquid (such as MOP and EOP), reducing energy loss, and avoiding energy waste, thereby improving the fuel consumption level of the whole vehicle and increasing the cruising range.

[0132] Those skilled in the art will appreciate that, in the above method of specific implementation, the order in which the steps are written does not imply a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of the steps should be determined by their functions and possible internal logic.

[0133] Based on the motor temperature control method provided in the above method embodiment, the present application embodiment also provides a motor temperature control device, and the motor temperature control device will be described below in conjunction with the accompanying drawings. Since the principle of the problem solved by the device in the embodiment of the present disclosure is similar to the motor temperature control method in the embodiment of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0134] See also Figure 4 As shown in FIG. 1 , this figure is a schematic diagram of the structure of a motor temperature control device provided in an embodiment of the present application. Figure 4 As shown, the motor temperature control device comprises:

[0135] The first acquisition unit 401 is used to acquire the basic heat dissipation power of the motor of the vehicle and the heat dissipation power of the motor working loss; the basic heat dissipation power of the motor is determined by the current temperature of the motor and the target temperature of the motor;

[0136] A calculation unit 402 is used to calculate the total heat dissipation power of the motor based on the basic heat dissipation power of the motor and the heat dissipation power of the motor working loss;

[0137] The second acquisition unit 403 is used to acquire the temperature of the cooling liquid at the outlet of the cooling device based on the heat dissipation power of the cooling device; the inlet of the motor is connected to the outlet of the cooling device, and the cooling liquid delivered by the cooling device to the motor is used to achieve temperature control of the motor;

[0138] A third acquisition unit 404 is used to acquire a target flow rate of the cooling liquid corresponding to the motor at the current moment based on the total heat dissipation power of the motor, the temperature of the cooling liquid at the outlet of the cooling device, and the heating temperature of the cooling liquid, so as to control the temperature of the motor based on the cooling liquid of the target flow rate, so that the temperature of the cooling liquid is increased from the temperature of the cooling liquid at the outlet of the cooling device to the heating temperature of the cooling liquid, and the output power is equal to the total heat dissipation power of the motor, so as to reduce the motor from the current temperature of the motor to the target temperature of the motor;

[0139] Wherein, the heating temperature of the cooling liquid is the same as the cooling liquid temperature at the inlet of the cooling device.

[0140] In a possible implementation, the first acquiring unit 401 includes:

[0141] A first acquisition subunit is used to set a motor target temperature, and acquire a basic motor heat dissipation power of the vehicle based on the motor target temperature, the motor current temperature, the motor specific heat capacity and the motor mass;

[0142] The second acquisition subunit is used to acquire the motor working loss heat dissipation power of the vehicle based on the motor's electric power and mechanical power; the motor's electric power is determined by the motor's power supply current and motor supply voltage, and the motor's mechanical power is determined by the motor's output torque and the motor speed.

[0143] In a possible implementation, the second obtaining unit 403 includes:

[0144] A third acquisition subunit is used to acquire the heat exchange power between the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid; the heat exchange power between the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid are both used to characterize the heat dissipation power of the cooling device;

[0145] a fourth acquisition subunit, configured to acquire the cooling liquid temperature at the cooling device outlet based on a conservation relationship between the heat exchange power between the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid;

[0146] Among them, the heat exchange power between the cooling liquid and the cooling air is the heat dissipation power of the heat exchange between the cooling liquid and the cooling air; the heat dissipation power of the cooling liquid is the heat dissipation power of reducing the temperature of the cooling liquid at the inlet of the cooling device to the temperature of the cooling liquid at the outlet of the cooling device; the reduction of the temperature of the cooling liquid at the inlet of the cooling device to the temperature of the cooling liquid at the outlet of the cooling device is achieved by heat exchange between the cooling liquid and the cooling air.

[0147] In a possible implementation, the third acquisition subunit includes:

[0148] a fifth acquisition subunit, configured to acquire a heat exchange power between the cooling liquid and the cooling air based on a convection heat transfer coefficient of the cooling device, a heat exchange area of ​​the cooling device, a cooling liquid temperature at an inlet of the cooling device, and an ambient temperature;

[0149] The convection heat transfer coefficient of the cooling device is related to the speed of the vehicle and the opening degree of a fan in the vehicle, and the fan is used to deliver cooling air to the vehicle to reduce the temperature of the cooling liquid.

[0150] In a possible implementation, the third acquisition subunit includes:

[0151] a sixth acquisition subunit, configured to acquire the heat dissipation power of the cooling liquid based on the cooling liquid temperature at the inlet of the cooling device, the cooling liquid temperature at the outlet of the cooling device, the cooling liquid specific heat capacity, the cooling liquid density, and the total flow rate of the cooling liquid passing through the cooling device at the last moment;

[0152] Wherein, the temperature of the cooling liquid at the outlet of the cooling device is the same as the temperature of the cooling liquid at the inlet of the motor.

[0153] In a possible implementation, the third obtaining unit 404 includes:

[0154] A calculation subunit, configured to calculate a motor cooling convection heat transfer coefficient based on the total heat dissipation power of the motor, the motor cooling heat exchange area, the cooling liquid temperature at the outlet of the cooling device, and the heating temperature of the cooling liquid;

[0155] The seventh acquisition subunit is used to acquire the target flow rate of the cooling liquid at the current moment corresponding to the motor cooling convection heat transfer coefficient based on the calibration relationship between the motor cooling convection heat transfer coefficient and the cooling liquid flow rate.

[0156] In a possible implementation manner, the device further includes:

[0157] A fourth acquisition unit is used to acquire the total motor cooling flow rate at the current moment based on the target flow rate of the cooling liquid corresponding to each motor at the current moment; the total motor cooling flow rate at the current moment and the cooling flow rate corresponding to the vehicle target device constitute the total cooling liquid flow rate at the current moment;

[0158] A first determining unit is used to determine the control ratio of the valve corresponding to each motor based on the total motor cooling flow at the current moment; the motor is connected to the cooling device through the valve;

[0159] The second determining unit is used to determine the opening degree of each valve based on the control ratio of each valve.

[0160] It should be noted that the specific implementation of each unit in this embodiment can refer to the relevant description in the above method embodiment. The division of units in the embodiment of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation. The functional units in the embodiment of the present application can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. For example, in the above embodiment, the processing unit and the sending unit can be the same unit or different units. The above integrated units can be implemented in the form of hardware or in the form of software functional units.

[0161] An embodiment of the present application further provides a computer-readable medium having a computer program stored thereon, wherein when the program is executed by a processor, the motor temperature control method as described above is implemented.

[0162] See also Figure 5 , Figure 5 A schematic diagram illustrating an electronic device according to an exemplary embodiment of the present disclosure.

[0163] Reference Figure 5 According to an exemplary embodiment of the present disclosure, an electronic device includes a storage device 51 and one or more processors 52, wherein the storage device 51 stores one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors implement any of the motor temperature control methods described above.

[0164] In an exemplary embodiment of the present disclosure, when the computer program is executed by the processor 52, the following steps may be implemented:

[0165] Obtaining the basic heat dissipation power of the motor of the vehicle and the heat dissipation power of the motor working loss; the basic heat dissipation power of the motor is determined by the current temperature of the motor and the target temperature of the motor;

[0166] Calculating the total heat dissipation power of the motor based on the basic heat dissipation power of the motor and the working loss heat dissipation power of the motor;

[0167] Based on the heat dissipation power of the cooling device, the temperature of the cooling liquid at the outlet of the cooling device is obtained; the inlet of the motor is connected to the outlet of the cooling device, and the cooling liquid delivered by the cooling device to the motor is used to achieve temperature control of the motor;

[0168] Based on the total heat dissipation power of the motor, the temperature of the cooling liquid at the outlet of the cooling device, and the heating temperature of the cooling liquid, a target flow rate of the cooling liquid corresponding to the motor at the current moment is obtained, and the temperature of the motor is controlled based on the cooling liquid with the target flow rate, so that the temperature of the cooling liquid is increased from the cooling liquid temperature at the outlet of the cooling device to the heating temperature of the cooling liquid, and the output power is equal to the total heat dissipation power of the motor, so as to reduce the motor from the current temperature of the motor to the target temperature of the motor;

[0169] Wherein, the heating temperature of the cooling liquid is the same as the cooling liquid temperature at the inlet of the cooling device.

[0170] It can be known from the description of the above implementation mode that those skilled in the art can clearly understand that all or part of the steps in the above-mentioned embodiment method can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product can be stored in a storage medium such as ROM / RAM, a disk, an optical disk, etc., including several instructions for enabling a computer device (which can be a personal computer, a server, or a network communication device such as a media gateway, etc.) to execute the methods described in the various embodiments of the present application or certain parts of the embodiments.

[0171] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referred to each other. For the method disclosed in the embodiment, since it corresponds to the system disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the system part description.

[0172] It should also be noted that, in this article, the term "comprises", "includes" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0173] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A motor temperature control method, characterized in that: The method comprises: Obtaining the basic heat dissipation power of the motor of the vehicle and the heat dissipation power of the motor working loss; the basic heat dissipation power of the motor is determined by the current temperature of the motor and the target temperature of the motor; Calculating the total heat dissipation power of the motor based on the basic heat dissipation power of the motor and the working loss heat dissipation power of the motor; Based on the heat dissipation power of the cooling device, the temperature of the cooling liquid at the outlet of the cooling device is obtained; the inlet of the motor is connected to the outlet of the cooling device, and the cooling liquid delivered by the cooling device to the motor is used to achieve temperature control of the motor; Based on the total heat dissipation power of the motor, the temperature of the cooling liquid at the outlet of the cooling device, and the heating temperature of the cooling liquid, a target flow rate of the cooling liquid corresponding to the motor at the current moment is obtained, and the temperature of the motor is controlled based on the cooling liquid with the target flow rate, so that the temperature of the cooling liquid is increased from the cooling liquid temperature at the outlet of the cooling device to the heating temperature of the cooling liquid, and the output power is equal to the total heat dissipation power of the motor, so as to reduce the motor from the current temperature of the motor to the target temperature of the motor; Wherein, the heating temperature of the cooling liquid is the same as the cooling liquid temperature at the inlet of the cooling device.

2. The method according to claim 1, characterized in that: The obtaining of the basic heat dissipation power of the motor of the vehicle and the heat dissipation power of the motor working loss includes: Setting a motor target temperature, and obtaining a basic motor heat dissipation power of the vehicle based on the motor target temperature, the motor current temperature, the motor specific heat capacity, and the motor mass; Based on the electric power and mechanical power of the motor, the working loss heat dissipation power of the motor of the vehicle is obtained; the electric power of the motor is determined by the power supply current and the motor supply voltage of the motor, and the mechanical power of the motor is determined by the motor output torque of the motor and the motor speed of the motor.

3. The method according to claim 1, characterized in that The step of obtaining the cooling liquid temperature at the outlet of the cooling device based on the heat dissipation power of the cooling device comprises: Obtaining the heat exchange power between the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid; the heat exchange power between the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid are both used to characterize the heat dissipation power of the cooling device; Based on the conservation relationship between the heat exchange power between the cooling liquid and the cooling air and the heat dissipation power of the cooling liquid, obtaining the cooling liquid temperature at the cooling device outlet; Among them, the heat exchange power between the cooling liquid and the cooling air is the heat dissipation power of the heat exchange between the cooling liquid and the cooling air; the heat dissipation power of the cooling liquid is the heat dissipation power of reducing the temperature of the cooling liquid at the inlet of the cooling device to the temperature of the cooling liquid at the outlet of the cooling device; the reduction of the temperature of the cooling liquid at the inlet of the cooling device to the temperature of the cooling liquid at the outlet of the cooling device is achieved by heat exchange between the cooling liquid and the cooling air.

4. The method according to claim 3, characterized in that: The step of obtaining the heat exchange power between the cooling liquid and the cooling air comprises: Obtaining heat exchange power between the cooling liquid and the cooling air based on a convection heat transfer coefficient of a cooling device, a heat exchange area of ​​the cooling device, a cooling liquid temperature at an inlet of the cooling device, and an ambient temperature; The convection heat transfer coefficient of the cooling device is related to the speed of the vehicle and the opening degree of a fan in the vehicle, and the fan is used to deliver cooling air to the vehicle to reduce the temperature of the cooling liquid.

5. The method according to claim 3, characterized in that: The step of obtaining the heat dissipation power of the cooling liquid comprises: Obtaining the heat dissipation power of the cooling liquid based on the cooling liquid temperature at the inlet of the cooling device, the cooling liquid temperature at the outlet of the cooling device, the cooling liquid specific heat capacity, the cooling liquid density, and the total flow rate of the cooling liquid passing through the cooling device at the last moment; Wherein, the temperature of the cooling liquid at the outlet of the cooling device is the same as the temperature of the cooling liquid at the inlet of the motor.

6. The method according to claim 1, characterized in that The step of obtaining a target flow rate of the cooling liquid corresponding to the motor at the current moment based on the total heat dissipation power of the motor, the cooling liquid temperature at the outlet of the cooling device, and the heating temperature of the cooling liquid comprises: Calculating the motor cooling convection heat transfer coefficient based on the total heat dissipation power of the motor, the motor cooling heat exchange area, the cooling liquid temperature at the outlet of the cooling device, and the heating temperature of the cooling liquid; Based on the calibration relationship between the motor cooling convection heat transfer coefficient and the cooling liquid flow rate, the target flow rate of the cooling liquid at the current moment corresponding to the motor cooling convection heat transfer coefficient is obtained.

7. The method according to any one of claims 1 to 6, characterized in that: The method further comprises: Based on the target flow rate of the cooling liquid corresponding to each motor at the current moment, the total cooling flow rate of the motor at the current moment is obtained; the total cooling flow rate of the motor at the current moment and the cooling flow rate corresponding to the target device of the vehicle constitute the total cooling liquid flow rate at the current moment; Based on the total motor cooling flow at the current moment, determining the control ratio of the valve corresponding to each motor; the motor is connected to the cooling device through the valve; Based on the control ratio of each valve, the opening degree of each valve is determined.

8. A motor temperature control device, characterized in that: The device comprises: A first acquisition unit is used to acquire a basic heat dissipation power of a motor and a heat dissipation power of a motor working loss of a vehicle; the basic heat dissipation power of the motor is determined by a current temperature of the motor and a target temperature of the motor; A calculation unit, used for calculating the total heat dissipation power of the motor based on the basic heat dissipation power of the motor and the heat dissipation power of the motor working loss; A second acquisition unit is used to acquire the temperature of the cooling liquid at the outlet of the cooling device based on the heat dissipation power of the cooling device; the inlet of the motor is connected to the outlet of the cooling device, and the cooling liquid delivered by the cooling device to the motor is used to achieve temperature control of the motor; a third acquisition unit, for acquiring a target flow rate of the cooling liquid corresponding to the motor at a current moment based on the total heat dissipation power of the motor, the temperature of the cooling liquid at the outlet of the cooling device, and the heating temperature of the cooling liquid, so as to control the temperature of the motor based on the cooling liquid of the target flow rate, so that the temperature of the cooling liquid is increased from the temperature of the cooling liquid at the outlet of the cooling device to the heating temperature of the cooling liquid, and the output power is equal to the total heat dissipation power of the motor, so as to reduce the motor from the current temperature of the motor to the target temperature of the motor; Wherein, the heating temperature of the cooling liquid is the same as the cooling liquid temperature at the inlet of the cooling device.

9. An electronic device, characterized in that: include: one or more processors; a storage device having one or more programs stored thereon, When the one or more programs are executed by the one or more processors, the one or more processors implement the motor temperature control method as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed by a processor, the motor temperature control method as described in any one of claims 1 to 7 is implemented.

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