Transient temperature control method and device of oil-cooled electric drive system and storage medium

Abstract

The application belongs to the technical field of new energy vehicles, and particularly relates to a transient temperature control method and device of an oil cooling electric drive system and a storage medium, which are applied to a temperature control device. The method comprises the following steps: obtaining target output power P1 and current output power P2 of the oil cooling electric drive system; according to a driving condition, when the output power of the oil cooling motor changes, the ratio of the target output power P1 to the current output power P2 is obtained; the cooling liquid circuit and the cooling oil circuit are controlled in parallel, and a control signal enters an oil cooling motor controller and a thermal management controller at the same time; and according to the ratio, the gear of the cooling liquid circuit and the cooling oil circuit is changed. The purpose is to improve the heat dissipation capacity of the whole system through linkage between the cooling oil circuit and the cooling liquid circuit, thereby improving the output capacity of the motor; and the hysteresis of the temperature control method is reduced, and the reliability of the system is improved by using the parallel control method.

Description

Technical Field

[0001] This invention belongs to the field of new energy vehicle technology, specifically relating to a transient temperature control method, device, and storage medium for an oil-cooled electric drive system. Background Technology

[0002] The continuous increase in carbon emissions is a key factor affecting the global climate. Among them, the carbon emissions of traditional energy vehicles are an important component of the total carbon emissions of society. Developing new energy vehicles to improve energy efficiency is an important technical means to reduce carbon emissions.

[0003] Unlike traditional gasoline-powered vehicles that use engines for propulsion, new energy vehicles, including plug-in hybrids, range-extended electric vehicles, and pure electric vehicles, all use electric drive systems as their primary or sole driving force. Functionally, an electric drive system includes a motor, motor controller, other electrical components, and auxiliary parts. In terms of functional design, multi-functionality is a crucial direction for the development of electric drive systems; in terms of performance parameters, improving the torque density and power density of the motor is a key focus. The demands of multi-functionality, increased power density, and increased torque density have driven the evolution of motor cooling methods from initial air and water cooling to oil cooling. Compared to water-cooled motors, cooling oil, driven by an oil pump, can enter the motor's interior, making more effective contact with the heat-generating components and increasing heat exchange capacity. Therefore, at the same output power, oil-cooled motors have the advantages of smaller size and lighter weight, and their peak output power is also higher than that of water-cooled motors, making them the mainstream electric drive system for new energy vehicles.

[0004] For example, Changan Automobile's patent 202210434619.8, "Oil Pump Control Method, System, and Vehicle for Oil-Cooled Motor System," discloses a control method that includes the following steps: acquiring the vehicle's operating mode, motor heating power, radiator inlet oil temperature, and motor speed; when the operating mode is any one of torque mode, pulse heating mode, and DC boost mode, determining the first oil pump speed corresponding to the operating mode based on the motor heating power and radiator inlet oil temperature; determining the second oil pump speed based on the motor speed and radiator inlet oil temperature; and using the larger value between the first and second oil pump speeds as the target required oil pump speed. This invention can cool the oil-cooled motor system effectively and in real time with low energy consumption, thus improving its reliability.

[0005] For example, Huawei Technologies Co., Ltd.'s patent 201910636889.5, "Oil-cooled Motor Control Device and Method," discloses an oil-cooled motor control device and method related to the field of electric vehicles, used to control the operating temperature of an oil-cooled motor. The oil-cooled motor temperature control device includes: an oil pump, a heat exchanger, a water pump, a controller, and an oil collection tank. The controller is used to: acquire the temperature of the lubricating oil in the oil collection tank; predict the predicted operating conditions of the oil-cooled motor based on at least one of driving mode, predicted road conditions, and driving habits; determine the temperature control target of the lubricating oil and the oil-cooled motor based on the predicted operating conditions of the oil-cooled motor; control the speed of the oil pump based on the predicted operating conditions of the oil-cooled motor, the temperature control target of the oil-cooled motor, and the temperature control target of the lubricating oil; and control the speed of the water pump based on the temperature of the coolant flowing into the heat exchanger, the temperature of the lubricating oil in the oil collection tank, the flow rate of the lubricating oil, and the temperature control target of the lubricating oil.

[0006] For example, United Electronics Corporation's patent 202110701699.4, "Online Thermal Management Method, Storage Medium, Motor Controller, and Management System for Oil-Cooled Motors," discloses an online thermal management method for oil-cooled motors, including: motor operation; acquiring real-time speed, motor output power, the maximum allowable temperature difference between the inlet and outlet of the cooling oil at the current speed, and the maximum loss value that can be borne; calculating the motor loss carried away by the cooling oil in real time based on the cooling oil flow rate, the oil temperature at the cooling oil inlet and outlet, and the maximum loss value that can be borne; and adjusting the maximum allowable output power of the motor in real time based on the current cooling oil inlet and outlet temperatures, the motor loss carried away by the cooling oil, the current maximum allowable temperature difference between the inlet and outlet of the cooling oil, and the maximum loss value that can be borne, so that the motor is in a thermally safe state. This invention achieves precise temperature control of oil-cooled motors at a very low cost, avoids motor damage caused by overheating, reduces motor operation risks, and improves the service life and safety of the motor.

[0007] The main shortcomings of existing publicly available technologies are concentrated in the following aspects:

[0008] 1. Other temperature control methods for oil-cooled motors disclosed in patents by Changan Automobile and United Automotive Electronics mainly focus on the impact of oil pump control on the temperature of the oil-cooled motor. They control the output power of the oil-cooled motor based on its heat dissipation capacity. The technical parameters for oil pump control are derived from the motor's output power and parameters of some auxiliary systems. The temperature control result is then obtained based on these parameters, ultimately limiting the motor's output power. However, the power output of the oil-cooled motor in new energy vehicles is a core aspect of the user experience. Due to the lack of coordination with an external thermal management system, the output power of the oil-cooled motor is highly limited. Therefore, the control method may significantly impact the user experience.

[0009] 2. As exemplified by Huawei's patent, this method utilizes the linkage between the oil-cooled motor's own cooling device (such as an oil pump) and the vehicle's thermal management system. However, the signal transmission between the two is sequential; that is, the oil pump is adjusted first, and then the water pump is adjusted as needed. This adjustment method has a significant time lag, which, under extreme conditions, may damage the motor due to the time lag. Summary of the Invention

[0010] The purpose of this invention is to provide a transient temperature control method, device, and storage medium for an oil-cooled electric drive system. By linking the cooling oil circuit and the coolant circuit, the heat dissipation capacity of the entire system is improved, thereby increasing the output capacity of the motor. At the same time, the hysteresis of the temperature control method is reduced, and the reliability of the system is improved by using parallel control.

[0011] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows:

[0012] In a first aspect, this application provides a transient temperature control method for an oil-cooled electric drive system, applied to a temperature control device, characterized by comprising the following steps:

[0013] Obtain the target output power P1 and current output power P2 of the oil-cooled electric drive system;

[0014] According to the driving conditions, when the output power of the oil-cooled motor changes, the control signal simultaneously enters the oil-cooled motor controller and the thermal management controller to obtain the ratio of the target output power P1 to the current output power P2. Based on this ratio, the power of the coolant circuit and the cooling oil circuit is changed, and the coolant circuit and the cooling oil circuit are controlled in parallel.

[0015] The oil-cooled motor controller is used to control the input power of the cooling oil circuit, and the thermal management controller is used to control the input power of the coolant circuit.

[0016] By controlling the coolant circuit and the cooling oil circuit in parallel, the operation of the coolant circuit and the cooling oil circuit can be controlled synchronously. This allows the operating status of the oil-cooled motor to be controlled according to different driving conditions of the vehicle, thereby controlling the transient temperature of the oil-cooled electric drive system. This makes the operation of the oil-cooled motor unrestricted by temperature conditions, thus improving the driving experience.

[0017] In conjunction with the first aspect, as some optional implementations, the method further includes,

[0018] When controlling the cooling oil circuit, the power boost ratio of the oil pump is calculated by taking the 3 / 4th root of the ratio of the target output power P1 to the current output power P2.

[0019] When the input power of the oil pump after the boost ratio is equal to that of the next oil pump gear, the oil pump directly enters the next power gear; when the input power of the oil pump after the boost ratio is less than the input power of the next oil pump gear, the input power of the oil pump remains unchanged.

[0020] The calculated values ​​of the target output power P1 and the current output power P2 are used as the power boost ratio of the oil pump, thereby controlling the input power of the oil pump. This is beneficial for the rapid heat dissipation of the oil-cooled motor and will not limit the output power of the oil-cooled motor.

[0021] In conjunction with the first aspect, as some optional implementations, the method further includes,

[0022] In coolant circuit control, the fan input power is changed according to the ratio of the target output power P1 to the current output power P2, by a multiple of P1 / P2.

[0023] When the input power is greater than or equal to the fan's current speed setting, the fan input power is adjusted to the next speed setting; when the input power is less than the current speed setting, the fan power is not adjusted.

[0024] By controlling the fan power using the ratio of the target output power P1 to the current output power P2, it is beneficial for the rapid heat dissipation of the coolant circuit.

[0025] In conjunction with the first aspect, as some optional implementations, the method further includes,

[0026] In coolant circuit control, the input power of the water pump is changed according to the ratio of the target output power P1 to the current output power P2, by a multiple of P1 / P2.

[0027] When the oil pump and fan both increase their speed, the water pump will not increase its speed. If neither the oil pump nor the fan increases its speed, the water pump will directly increase its speed by one level.

[0028] By controlling the fan power using the ratio of the target output power P1 to the current output power P2, the circulation efficiency of the coolant in the coolant circuit is improved, and the heat dissipation effect on the cooling oil circuit is enhanced without causing redundant cooling efficiency.

[0029] In conjunction with the first aspect, as some optional implementations, the method further includes,

[0030] When controlling the coolant circuit, the opening of the active air intake grille is changed according to the ratio of the target output power P1 to the current output power P2, by a multiple of P1 / P2.

[0031] When the active air intake grille reaches its maximum opening, the fan input power is adjusted according to the P1 / P2 ratio. If the input power is greater than or equal to the fan speed, the fan input power is adjusted to the next speed. If the active air intake grille is less than the maximum opening, the fan power is not adjusted.

[0032] When the oil pump increases its speed and the fan also increases its speed, the water pump will not increase its speed. If neither the oil pump nor the fan increases its speed, the water pump will directly increase its speed by one level.

[0033] By controlling the ratio of the target output power P1 to the current output power P2, the opening of the active air intake grille can be improved. On the one hand, this can further enhance the heat dissipation effect of the coolant circuit. On the other hand, it can reduce the output intensity of the fan, thereby reducing the power consumption of the vehicle.

[0034] Secondly, this application also discloses a temperature control device applied to the temperature control method described above. The temperature control device includes an oil-cooled motor, a coolant circuit, a cooling oil circuit, an oil-cooled motor controller, and a thermal management controller. The cooling oil circuit is connected to the oil-cooled motor. The oil-cooled motor includes a stator, a rotor, an oil reservoir, and a temperature sensor. The oil reservoir is disposed on one side of the rotor. The temperature sensor is disposed on the stator, the rotor, and the oil reservoir. The cooling oil circuit is connected to the stator, the rotor, and the oil reservoir.

[0035] In conjunction with the second aspect, as some optional implementations, the temperature sensor includes a first temperature sensor, a second temperature sensor, a third temperature sensor, and a fourth temperature sensor. The first temperature sensor is located at the inlet of the oil-cooled motor, the second temperature sensor is located at the stator, the third temperature sensor is located at the rotor, and the fourth temperature sensor is located on the oil reservoir. This configuration enables real-time monitoring of the temperature of the cooling oil passing through the motor stator, motor rotor, and oil reservoir, as well as real-time monitoring of the temperature of the cooling oil entering the motor stator and motor rotor.

[0036] In conjunction with the second aspect, as some optional implementations, the cooling oil circuit includes a filter, an oil pump, a plate heat exchanger, and oil pipes. The oil-cooled motor is connected to the filter, one end of the oil pump is connected to the filter, and the other end is connected to the plate heat exchanger. The oil pipes are connected between the plate heat exchanger and the oil-cooled motor. The oil-cooled motor controller controls the input power of the oil pump. With this configuration, the cooling oil after passing through the oil-cooled motor can be cooled through the plate heat exchanger.

[0037] In conjunction with the second aspect, as some optional implementations, the coolant circuit includes a water pump, a heat sink, and electrical components. One end of the water pump is connected to the heat sink, and the other end is connected to the cooling oil circuit. One end of the electrical components is connected to the cooling oil circuit, and the other end is connected to the heat sink. The thermal management controller is used to control the input power of the water pump and the heat sink. This configuration, on the one hand, can dissipate heat from the cooling oil circuit, thereby improving the heat dissipation capacity of the cooling oil circuit; on the other hand, the coolant in the coolant circuit can dissipate heat, thereby scattering heat to the outside, facilitating circulating heat dissipation.

[0038] In conjunction with the second aspect, as some optional implementations, the heat dissipation component includes a radiator and a fan, the fan being connected to the radiator, one end of the radiator being connected to an electrical functional component, and the other end being connected to a water pump. This configuration enables the dissipation of coolant in the coolant circuit.

[0039] In conjunction with the second aspect, as some optional implementations, the heat sink also includes an active air intake grille connected to the radiator, which further enhances the heat dissipation capacity of the coolant circuit.

[0040] In conjunction with the second aspect, as some optional implementations, the coolant circuit further includes a fifth temperature sensor and a sixth temperature sensor. The fifth temperature sensor is located at the inlet end of the heat sink, and the sixth temperature sensor is located at the outlet end of the heat sink. This configuration allows for real-time monitoring of the temperature of the coolant passing through the heat sink, thereby enabling the adjustment of the water pump power based on the temperature.

[0041] Thirdly, this application also provides a computer-readable storage medium storing a computer program that, when run on a computer, causes the computer to perform the methods described above.

[0042] The invention employing the above technical solution has the following advantages:

[0043] 1. By coordinating the oil-cooled motor, coolant circuit, and cooling oil circuit, and with the coolant circuit and cooling oil circuit arranged in series, the coolant circuit and cooling oil circuit can adjust the transient temperature of the oil-cooled electric drive system, which is beneficial to improving the heat dissipation capacity of the entire system, thereby improving the output capacity of the oil-cooled motor.

[0044] 2. By adopting parallel control of the coolant circuit and the cooling oil circuit, the heat dissipation of the coolant circuit and the cooling oil circuit can be controlled synchronously, which can reduce the lag of the existing temperature control method. Therefore, it will not limit the output power of the oil-cooled motor, which is conducive to improving the reliability of the system and the user experience. Attached Figure Description

[0045] This application can be further illustrated by the non-limiting embodiments given in the accompanying drawings. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as limiting the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0046] Figure 1 The frame of the temperature control device provided in the embodiments of this application Figure 1 ;

[0047] Figure 2 The frame of the temperature control device provided in the embodiments of this application Figure 2 ;

[0048] Figure 3 The frame of the temperature control device provided in the embodiments of this application Figure 3 ;

[0049] Figure 4 A flowchart illustrating the transient temperature control method for an oil-cooled electric drive system provided in this application embodiment. Figure 1 ;

[0050] Figure 5 A flowchart illustrating the transient temperature control method for an oil-cooled electric drive system provided in this application embodiment. Figure 2 ;

[0051] The symbols for the main components are explained below:

[0052] Oil-cooled motor 1, stator 101, rotor 102, second temperature sensor 103, third temperature sensor 104, oil reservoir 105, fourth temperature sensor 106, first temperature sensor 107, filter 11, oil pump 12, plate heat exchanger 13.

[0053] Electrical functional components 2, radiator 21, fan 22, water pump 23, sixth temperature sensor 24, fifth temperature sensor 25, active air intake grille 26. Detailed Implementation

[0054] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. It should be noted that the illustrations provided in the following embodiments are for illustrative purposes only and represent schematic diagrams, not actual pictures, and should not be construed as limiting the present invention. In order to better illustrate the embodiments of the present invention, some components in the figures may be omitted, enlarged, or reduced, and do not represent the actual product size; it is understandable for those skilled in the art that some well-known structures and their descriptions may be omitted in the figures.

[0055] In the figures of this invention, the same or similar reference numerals correspond to the same or similar components. In the description of this invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the figure, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the figures are only for illustrative purposes and should not be construed as limiting this invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances. In the description of this application, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0056] like Figures 1-3 As shown in the illustration, this application provides a temperature control device, including an oil-cooled motor 1, a coolant circuit, and a cooling oil circuit. The cooling oil circuit is connected to the oil-cooled motor via a pipeline. The cooling oil circuit is used for transient temperature control of the oil-cooled motor, and the coolant circuit is used for temperature control of the cooling oil circuit. The coolant circuit and the cooling oil circuit are controlled in parallel, enabling them to work together to improve the heat dissipation capacity of the oil-cooled electric drive system, thereby increasing the output power of the oil-cooled motor and ultimately enhancing the user's driving experience.

[0057] In some alternative embodiments, such as Figure 1 As shown, the cooling oil circuit includes a filter 11, an oil pump 12, a plate heat exchanger 13, and oil pipes. The output end of the oil-cooled motor 1 is connected to the filter 11, allowing the filter to filter the cooling oil passing through the oil-cooled motor 1. The input end of the oil pump 12 is connected to the output end of the filter 11, and the output end of the oil pump 12 is connected to the input end of the plate heat exchanger 13. The oil pipes connect the output end of the plate heat exchanger 13 and the input end of the oil-cooled motor 1, and the cooling oil exists in the oil pipes. When the oil pump 12 is working, it allows the cooling oil to circulate between the filter 11, the oil pump 12, the plate heat exchanger 13, and the oil-cooled motor 1, and dissipates heat through the plate heat exchanger 13. This dissipates heat from the cooling oil after it has passed through the oil-cooled motor 1, thereby controlling the transient temperature of the oil-cooled motor 1 and improving its output power.

[0058] In some alternative embodiments, such as Figure 2As shown, the oil-cooled motor 1 includes a stator 101, a rotor 102, an oil reservoir 105, and a temperature sensor. The oil reservoir 105 is mounted on one side of the rotor 102, which extends out of the stator 101. During circulation, the cooling oil in the oil reservoir 105 passes through the stator 101 and rotor 102, carrying away the heat generated by the motor stator and rotor during operation, which is beneficial for the continuous operation of the oil-cooled motor 1. The temperature sensor is mounted on the stator 101, rotor 102, and oil reservoir 105, and can monitor the temperature of the cooling oil passing through the motor stator, rotor, and oil reservoir 105 in real time.

[0059] In this embodiment, the temperature sensors include a first temperature sensor 107, a second temperature sensor 103, a third temperature sensor 104, and a fourth temperature sensor 106. The first temperature sensor 107 is mounted at the inlet of the oil-cooled motor 1 to monitor the temperature of the cooling oil entering the oil-cooled motor 1 in real time. The second temperature sensor 103 is mounted on the stator 101 to monitor the cooling effect of the cooling oil on the stator 101 in real time. The third temperature sensor 103 is mounted on the rotor 102 to monitor the cooling effect of the cooling oil on the rotor 102 in real time. The fourth temperature sensor 106 is disposed on the oil reservoir 105 to monitor the temperature of the cooling oil in the oil reservoir 105 in real time.

[0060] Through the cooperation of the first temperature sensor 107, the second temperature sensor 103, the third temperature sensor 104, and the fourth temperature sensor 106, the temperature of the cooling oil passing through the motor stator, the motor rotor, and the oil reservoir 105 can be monitored in real time, and the temperature of the cooling oil entering the motor stator and the motor rotor can also be monitored in real time. The oil-cooled motor controller can collect data from the first temperature sensor 107, the second temperature sensor 103, the third temperature sensor 104, and the fourth temperature sensor 106, and thus adjust the output power of the oil pump 12 according to the collected data, so that the oil-cooled motor 1 is no longer limited by temperature, which is conducive to improving the output capacity of the oil-cooled motor 1.

[0061] In this embodiment, the cooling oil circuit also includes an oil-cooled motor controller. The oil-cooled motor controller is used to control the input power of the oil pump 12, that is, to control the speed of the oil pump 12. By controlling the speed of the oil pump 12, the heat exchange capacity between the cooling oil and the rotor and stator can be controlled, thereby controlling the transient temperature of the oil-cooled motor 1 and collecting the operating parameters of the oil pump 12.

[0062] In some alternative embodiments, such as Figure 1As shown, the coolant circuit includes a water pump 23, a radiator, and an electrical component 2. The input end of the water pump 23 is connected to the radiator, and the output end of the water pump 23 is connected to the plate heat exchanger 13 via a pipeline, allowing the coolant to exchange heat with the cooling oil passing through the plate heat exchanger 13. The coolant, containing ethylene glycol, exists in the pipeline. On one hand, it can dissipate heat from the cooling oil circuit, thereby improving the heat dissipation capacity of the cooling oil circuit; on the other hand, the coolant in the coolant circuit can dissipate heat to the outside, facilitating circulating heat dissipation. One end of the electrical component 2 is connected to the plate heat exchanger 13, and the other end is connected to the radiator. It is used to control the speed of the water pump 23 and the working state of the radiator, thereby controlling the heat dissipation capacity of the coolant.

[0063] In an optional embodiment, such as Figure 3 As shown, the heat dissipation component includes a radiator 21 and a fan 22. The fan 22 is fixedly connected to the radiator 21. The input end of the radiator 21 is connected to the thermal management controller, and the output end of the radiator 21 is connected to the input end of the water pump 23. Through the cooperation of the radiator 21 and the fan 22, the coolant in the coolant circuit can be cooled, and through the operation of the fan 22, the heat of the coolant and the radiator 21 can be dissipated to the external environment.

[0064] In an optional embodiment, the heat sink may further include an active air intake grille 26, which is fixedly connected to the other side of the radiator 21. The active air intake grille 26 reduces airflow resistance during the cooling process of the fan 22. Through the cooperation of the radiator 21, fan 22, and active air intake grille 26, the heat dissipation capacity of the coolant circuit can be further enhanced.

[0065] In this embodiment, the electrical functional component 2 also includes a thermal management controller, which is used to control the input power of the water pump 23, radiator 21, fan 22 and active air intake grille 26, and to collect the operating status parameters of the water pump 23, radiator 21, fan 22 and active air intake grille 26.

[0066] In this embodiment, the coolant circuit also includes a fifth temperature sensor 25 and a sixth temperature sensor 24. The fifth temperature sensor 25 is mounted at the inlet end of the radiator 21 and is used to monitor the temperature of the coolant entering the radiator 21 in real time. The sixth temperature sensor 24 is mounted at the outlet end of the radiator 21 and is used to monitor the temperature of the coolant after passing through the radiator 21 in real time. The thermal management controller can collect data from the fifth temperature sensor 25 and the sixth temperature sensor 24, and thus can adjust the power of the water pump 23 according to the temperature.

[0067] Please refer to the attached document. Figure 4-5This application also provides a transient temperature control method for an oil-cooled electric drive system, applied to the temperature control device as described in the above embodiments. The method includes:

[0068] Obtain the target output power P1 and current output power P2 of the oil-cooled electric drive system;

[0069] Depending on the driving conditions, when the output power of the oil-cooled motor changes, the control signal simultaneously enters the oil-cooled motor controller and the thermal management controller to obtain the ratio of the target output power P1 to the current output power P2. Based on this ratio, the gears of the coolant circuit and the cooling oil circuit are changed, and the coolant circuit and the cooling oil circuit are controlled in parallel.

[0070] The oil-cooled motor controller is used to control the input power of the cooling oil circuit, and the thermal management controller is used to control the input power of the coolant circuit.

[0071] Existing transient temperature control methods for oil-cooled electric drive systems are primarily based on linear control. This means that when a user demands increased output torque from the oil-cooled electric drive system, corresponding adjustments to the temperature control capability are required. Based on torque change signals, the cooling oil circuit is first adjusted to improve heat dissipation, i.e., increasing the oil pump speed to increase heat dissipation. If the oil cooling circuit adjustment cannot provide sufficient heat dissipation, then the coolant circuit is adjusted to further enhance heat dissipation, thus achieving transient temperature control of the oil-cooled electric drive system. The main drawback of linear control is the temperature lag issue with series-connected temperature control devices, which may damage the motor.

[0072] This application adopts a temperature control method that uses parallel coolant circuit and cooling oil circuit, which can synchronously control the operation of coolant circuit and cooling oil circuit. This allows for control of the operating state of the oil-cooled motor according to different driving conditions of the vehicle, thereby controlling the transient temperature of the oil-cooled electric drive system. This ensures that the operation of the oil-cooled motor 1 is not limited by temperature conditions, thus improving the driving experience.

[0073] Understandably, the oil-cooled motor controller is used to control the speed of the oil pump 12 in the cooling oil circuit, and the thermal management controller is used to control the input power of the water pump 23 and the heat sink in the coolant circuit.

[0074] Understandably, when the controller of the cooling oil circuit receives the output power demand of the electric drive system, i.e., when the user needs to increase the output power of the oil-cooled motor 1 for acceleration or hill climbing, it obtains the power ratio P1 / P2, where P1 is the target output power and P2 is the current output power, and P1 / P2 > 1. After obtaining this ratio, the 3 / 4 root of the P1 / P2 ratio is used as the input power boosting factor of the oil pump 12, i.e., the current oil pump input power P. 0油泵Multiplying the ratio of P1 / P2 by the 3 / 4 power gives the target input power of oil pump 12. If the target input power of oil pump 12 after the boost ratio is greater than the upper limit of the current oil pump input power level, then the target input power of oil pump 12 is calculated according to the current oil pump input power P. 0油泵 Multiply by the 3 / 4 power of the ratio of P1 / P2. If the input power of the oil pump 12 after the boost ratio is not greater than the upper limit of the current oil pump input power level, then the input power of the oil pump 12 remains unchanged.

[0075] In this embodiment, the oil pump 12 can be set to the highest input power of 0W and the first gear can be set to the highest input power P×10%.

[0076] Understandably, during the process of adjusting the input power of oil pump 12 based on changes in the output power demand of oil-cooled motor 1, when the controller of the coolant circuit receives the output power demand of the electric drive system, i.e., when the user needs to accelerate or climb hills to increase the output power of oil-cooled motor 1, it obtains the power ratio P1 / P2, where P1 is the target output power and P2 is the current output power, and P1 / P2 > 1. After obtaining this ratio, the 3 / 4 root of the P1 / P2 ratio is used as the input power boost factor of fan 22, i.e., the current input power P of fan 22. 0风扇 Multiplying the ratio of P1 / P2 by the 3 / 4 power gives the target input power of fan 22. If the target input power of fan 22 after the multiplier is increased is greater than the upper limit of the current input power setting of fan 22, then the target input power of fan 22 is calculated according to the current fan input power P. 0风扇 Multiply by the 3 / 4 power of the ratio of P1 / P2. If the input power of fan 22 after the multiplier is increased is not greater than the upper limit of the current fan input power level, then the input power of fan 22 remains unchanged.

[0077] For the water pump 23 in the coolant circuit, if the oil pump 12 increases its input power and the fan 22 increases its input power, the water pump 23 will maintain its current gear. If the input power of the oil pump and the input power of the fan remain unchanged, the water pump 23 will directly increase to a gear and output power at the median of the next gear.

[0078] Please refer to the attached document. Figure 5 In the transient temperature control method of the oil-cooled electric drive system described above, when an active air intake grille 26 is installed on the other side of the radiator 21, the active air intake grille 26 is used to reduce wind resistance and further improve the radiator's heat dissipation efficiency for the coolant.

[0079] Specifically, when the controller of the cooling oil circuit receives the output power demand of the electric drive system, i.e., when the user needs to increase the output power of the oil-cooled motor 1 for acceleration or hill climbing, it obtains the power ratio P1 / P2, where P1 is the target output power and P2 is the current output power, and P1 / P2 > 1. After obtaining this ratio, the 3 / 4 root of the P1 / P2 ratio is used as the input power boosting factor of the oil pump 12, i.e., the current oil pump input power P. 0油泵 Multiplying the ratio of P1 / P2 by the 3 / 4 power gives the target input power of oil pump 12. If the target input power of oil pump 12 after the boost ratio is greater than the upper limit of the current oil pump input power level, then the target input power of oil pump 12 is calculated according to the current oil pump input power P. 0油泵 Multiply by the 3 / 4 power of the ratio of P1 / P2. If the input power of the oil pump 12 after the boost ratio is not greater than the upper limit of the current oil pump input power level, then the input power of the oil pump 12 remains unchanged.

[0080] In this embodiment, the oil pump 12 can be set to the highest input power of 0W and the first gear can be set to the highest input power P×10%.

[0081] Understandably, during the process of adjusting the oil pump input power based on changes in the oil-cooled motor's output power demand by the oil-cooled motor controller; when the coolant circuit controller receives the output power demand of the electric drive system, i.e., when the user needs to accelerate or climb hills to increase the output power of the oil-cooled motor, it obtains the power ratio P1 / P2, where P1 is the target output power and P2 is the current output power. After obtaining this ratio, it uses 1.2 times P1 / P2 as the target opening degree of the active air intake grille 26; when the active air intake grille 26 reaches its maximum opening degree greater than or equal to 100%, it uses the 3 / 4 power of the P1 / P2 ratio as the input power boost factor of the fan 22, i.e., the current input power P of the fan 22. 0风扇 Multiplying the ratio of P1 / P2 by the 3 / 4 power gives the target input power of fan 22. If the target input power of fan 22 after the multiplier is increased is greater than the upper limit of the current input power setting of fan 22, then the target input power of fan 22 is calculated according to the current fan input power P. 0风扇 Multiply by the 3 / 4 power of the ratio of P1 / P2. If the target opening of the active air intake grille 26 is not greater than 100%, then the input power of the fan 22 remains unchanged.

[0082] For the water pump 23 in the coolant circuit, if the oil pump 12 increases its input power and the fan 22 increases its input power, the current gear of the water pump 23 remains unchanged; if the input power of the oil pump and the input power of the fan remain unchanged, the water pump 23 directly increases to a gear and outputs power at the median of the next gear of the water pump 23.

[0083] This application also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program that, when executed on a computer, causes the computer to perform the braking control method as described in the above embodiments.

[0084] Based on the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by hardware or by using software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solution of this application can be embodied in the form of a software product. The software product can be stored in a non-volatile storage medium (such as CD-ROM, USB flash drive, mobile hard drive, etc.) and includes several instructions to cause a computer device (such as a personal computer, braking device, or network device, etc.) to execute the methods described in the various implementation scenarios of this application.

[0085] In summary, the embodiments of this application provide a transient temperature control method, device, and storage medium for an oil-cooled electric drive system. By linking the cooling oil circuit and the coolant circuit, the heat dissipation capacity of the entire system is improved, thereby enhancing the output capacity of the motor. At the same time, the hysteresis of the temperature control method is reduced, and the reliability of the system is improved by using parallel control.

[0086] In the embodiments provided in this application, it should be understood that the disclosed apparatus, systems, and methods can also be implemented in other ways. The apparatus, systems, and methods embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code, which includes one or more executable instructions for implementing a specified logical function. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions. Furthermore, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0087] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A transient temperature control method for an oil-cooled electric drive system, applied to a temperature control device, characterized in that, The steps include obtaining the target output power P1 and the current output power P2 of the oil-cooled electric drive system; According to the driving conditions, when the output power of the oil-cooled motor changes, the control signal simultaneously enters the oil-cooled motor controller and the thermal management controller to obtain the ratio of the target output power P1 to the current output power P2. Based on this ratio, the gears of the coolant circuit and the cooling oil circuit are changed, and the coolant circuit and the cooling oil circuit are controlled in parallel. The oil-cooled motor controller is used to control the input power of the cooling oil circuit, and the thermal management controller is used to control the input power of the coolant circuit.

2. The method according to claim 1, characterized in that: The method further includes, during cooling oil circuit control, using the ratio of target output power P1 to current output power P2, and taking the 3 / 4th power of the ratio P1 / P2 as the power boosting factor of the oil pump; when the oil pump input power after the boosting factor corresponds to the next oil pump gear, the oil pump directly enters the next oil pump gear; when the oil pump input power after the boosting factor is less than the input power of the next oil pump gear, the oil pump input power remains unchanged.

3. The method according to claim 1, characterized in that: The method further includes, during coolant circuit control, adjusting the fan input power according to the ratio of target output power P1 to current output power P2, using a multiple of P1 / P2; when the fan speed corresponding to the fan input power is greater than or equal to the current fan speed, adjusting the fan speed corresponding to the fan input power to the next fan speed; when the fan speed corresponding to the fan input power is less than the current fan speed, the fan power is not adjusted.

4. The method according to claim 3, characterized in that: The method further includes, during coolant circuit control, changing the input power of the water pump according to the ratio of the target output power P1 to the current output power P2, by a multiple of P1 / P2; when the oil pump increases its speed and the fan increases its speed, the water pump does not increase its speed; when the oil pump does not increase its speed or the fan does not increase its speed, the water pump directly increases its speed by one level.

5. The method according to claim 3, characterized in that: The method further includes, during coolant circuit control, adjusting the opening of the active air intake grille according to the ratio of the target output power P1 to the current output power P2, using a multiple of P1 / P2; when the active air intake grille reaches its maximum opening, adjusting the fan input power according to the multiple of P1 / P2; if the fan speed corresponding to the fan input power is greater than or equal to the current fan speed, adjusting the fan speed corresponding to the fan input power to the next fan speed; if the active air intake grille is less than the maximum opening, the fan power is not adjusted; when the oil pump increases its speed and the fan increases its speed, the water pump does not increase its speed; when the oil pump does not increase its speed or the fan does not increase its speed, the water pump directly increases its speed by one level.

6. A temperature control device applied to the method as described in any one of claims 1-5, characterized in that, The temperature control device includes an oil-cooled motor, a coolant circuit, a cooling oil circuit, an oil-cooled motor controller, and a thermal management controller. The cooling oil circuit is connected to the oil-cooled motor. The oil-cooled motor includes a stator, a rotor, an oil reservoir, and a temperature sensor. The oil reservoir is located on one side of the rotor. The temperature sensor is located on the stator, the rotor, and the oil reservoir. The cooling oil circuit is connected to the stator, the rotor, and the oil reservoir.

7. The temperature control device according to claim 6, characterized in that: The temperature sensor includes a first temperature sensor, a second temperature sensor, a third temperature sensor, and a fourth temperature sensor. The first temperature sensor is located at the inlet of the oil-cooled motor, the second temperature sensor is located at the stator, the third temperature sensor is located at the rotor, and the fourth temperature sensor is located on the oil reservoir.

8. The temperature control device according to claim 6, characterized in that: The cooling oil circuit includes a filter, an oil pump, a plate heat exchanger, and oil pipes. The oil-cooled motor is connected to the filter. One end of the oil pump is connected to the filter, and the other end is connected to the plate heat exchanger. The oil pipes are connected between the plate heat exchanger and the oil-cooled motor. The oil-cooled motor controller controls the input power of the oil pump.

9. The temperature control device according to claim 6, characterized in that: The coolant circuit includes a water pump, a heat sink, and electrical components. One end of the water pump is connected to the heat sink, and the other end is connected to the cooling oil circuit. One end of the electrical components is connected to the cooling oil circuit, and the other end is connected to the heat sink. The thermal management controller is used to control the input power of the water pump and the heat sink.

10. The temperature control device according to claim 9, characterized in that: The heat dissipation component includes a radiator and a fan. The fan is connected to the radiator. One end of the radiator is connected to an electrical functional component, and the other end is connected to a water pump.

11. The temperature control device according to claim 9, characterized in that: The heat dissipation component also includes an active air intake grille, which is connected to the radiator.

12. The temperature control device according to claim 9, characterized in that: The coolant circuit also includes a fifth temperature sensor and a sixth temperature sensor. The fifth temperature sensor is located at the inlet end of the heat sink, and the sixth temperature sensor is located at the outlet end of the heat sink.

13. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when run on a computer, causes the computer to perform the method as described in any one of claims 1-5.

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