Cooling control method and system for a hybrid vehicle after shutdown

Abstract

The application provides a cooling control method and system for a hybrid vehicle after shutdown, the method comprising: acquiring a power supply voltage of the vehicle, and determining whether the power supply voltage satisfies a cooling enabling condition; when the shutdown cooling enabling condition is satisfied, acquiring a gearbox oil temperature and a clutch temperature; determining an oil temperature interval in which the gearbox oil temperature is located, and determining a clutch temperature interval in which each clutch temperature is located; when there is a temperature interval that needs to be cooled in the oil temperature interval in which the gearbox oil temperature is located and the clutch temperature interval in which the clutch temperature is located, determining a corresponding cooling demand time for each temperature interval that needs to be cooled according to the temperature interval; determining a maximum value of all cooling demand times corresponding to the temperature intervals that need to be cooled as a duration of this time of cooling after shutdown; and controlling a cooling component to work for the duration, so that precise control of the cooling process after shutdown of the hybrid vehicle is realized.

Description

Technical Field

[0001] This invention belongs to the field of thermal management technology for hybrid vehicles, and specifically relates to a cooling control method and system for hybrid vehicles after shutdown. Background Technology

[0002] Dedicated hybrid power transmissions (DHTs) need to integrate components such as generators, drive motors, clutches, and gear sets within a limited space. This highly integrated structure results in a compact internal layout and inherently limited cooling channels. When the vehicle is powered off after operating under high load conditions, the oil temperature and clutch temperature inside the transmission may still remain at a high level, posing a risk of overheating.

[0003] To address the above issues, the two main approaches currently available are as follows: Option 1: No active cooling measures are taken; the transmission relies on natural heat exchange with the surrounding environment for cooling. This option has a low cooling rate, especially when the ambient temperature is high or the vehicle is parked in a poorly ventilated area, where the temperature of the fluids and clutch may not decrease effectively for an extended period.

[0004] Option 2: After power-off, monitor the oil and clutch temperatures. If either the oil or clutch temperature exceeds a preset single fixed threshold, continuously drive the electric oil pump, electric fan, and cooling water pump for forced cooling until the temperature drops below the threshold. While this option achieves active cooling, its judgment logic and control strategy are relatively simple, relying solely on a single temperature threshold for on / off control.

[0005] The above-mentioned Option 1 has the following drawbacks: the natural cooling rate is too slow, the longer the transmission fluid stays at high temperature, the faster the oxidation rate and the faster the fluid quality deteriorates; the aging rate of rubber seals increases exponentially under high temperature conditions, and long-term exposure to high temperatures will significantly shorten the service life of the seals; the clutch friction plates are at risk of sticking at high temperatures, affecting subsequent performance; and the electronic components such as oil temperature sensors and speed sensors inside the transmission will have their service life shortened when working under high temperature conditions for a long time, and may even cause sensor readings to drift or fail.

[0006] The above-mentioned Solution 2 has the following drawbacks: Prolonged operation of the electronic oil pump, electronic fan, and coolant pump after power-off will cause deep discharge of the vehicle's 12V battery (especially a standard lead-acid battery). After each excessive discharge, the internal plates of the battery will sulfate, causing an irreversible decrease in battery capacity, easily leading to subsequent sudden power failures and shortening the battery's lifespan. Simultaneously, the prolonged continuous operation of the cooling components will cause unnecessary mechanical wear, reducing their lifespan. Furthermore, when the vehicle is powered on again after power-off, regardless of whether the oil and clutch temperatures are still too high, the cooling components will not engage, resulting in the system failing to obtain effective over-temperature protection during the initial power-on phase.

[0007] In summary, existing technologies lack a sophisticated control strategy for cooling control of hybrid vehicles after shutdown that can ensure effective cooling while also protecting the battery and reducing mechanical wear. This invention addresses these issues. Summary of the Invention

[0008] To address the aforementioned technical problems, this invention provides a cooling control method and system for hybrid vehicles after shutdown, which solves the technical problems in the prior art.

[0009] On the one hand, the invention provides the following technical solution: a cooling control method for a hybrid vehicle after shutdown, the method comprising: Obtain the vehicle's power supply voltage and determine whether the power supply voltage meets the cooling enable conditions after shutdown. When the power supply voltage meets the shutdown cooling enable condition, the transmission oil temperature and at least one clutch temperature are obtained. Determine the oil temperature range of the transmission fluid and the clutch temperature range of each clutch. When there is at least one temperature range that requires cooling, between the oil temperature range where the transmission oil temperature is located and the clutch temperature range where the at least one clutch temperature is located, the corresponding cooling time is determined according to each temperature range that requires cooling. The maximum value among all cooling time requirements corresponding to the temperature range that needs to be cooled is determined as the duration of cooling after this shutdown; The vehicle's cooling components are controlled to operate for the specified duration.

[0010] Compared to existing technologies, the advantages of this application are as follows: By first acquiring the vehicle's power supply voltage and determining whether it meets the cooling enable conditions after shutdown, subsequent cooling control is not executed when the voltage does not meet the conditions. This effectively avoids the deep discharge and irreversible capacity reduction of the 12V battery caused by continuing to drive the cooling components when the battery power is insufficient, thus extending the battery's service life. Simultaneously, by dividing the transmission oil temperature and clutch temperature into different temperature ranges and determining whether cooling is needed and the corresponding cooling time based on each temperature range, precise timing control of cooling requirements is achieved. This avoids the problems caused by the electronic oil pump and electronic fan relying solely on a single threshold for continuous cooling in existing technologies. The unnecessary operation of the cooling water pump for extended periods reduces mechanical wear on cooling components. Furthermore, when at least one of the oil temperature and at least one clutch temperature requires cooling, the maximum cooling time corresponding to each required cooling temperature range is used as the duration of cooling after shutdown. This ensures that the component with the highest heat load receives sufficient cooling, effectively preventing problems such as accelerated oxidation of transmission fluid at high temperatures, accelerated aging of rubber seals, clutch friction plate adhesion, and shortened lifespan of internal electronic components due to prolonged high temperatures. Thus, while ensuring effective cooling, the system also optimizes battery energy consumption and mechanical wear on cooling components, achieving precise control of the cooling process after shutdown in hybrid vehicles.

[0011] Furthermore, the post-shutdown cooling enable condition includes: dividing the power supply voltage into at least one of a plurality of voltage ranges; The plurality of voltage ranges includes a first voltage range, a second voltage range, and a third voltage range; When the power supply voltage is in the first voltage range, the cooling enable condition after shutdown is not met; when the power supply voltage is in the second voltage range or the third voltage range, the cooling enable condition after shutdown is met. The voltage value in the third voltage range is higher than the voltage value in the second voltage range.

[0012] Furthermore, the oil temperature range of the transmission oil includes a first oil temperature range, a second oil temperature range, and a third oil temperature range, and the clutch temperature range of each clutch includes a first clutch temperature range, a second clutch temperature range, and a third clutch temperature range. Both the first oil temperature range and the first clutch temperature range are temperature ranges that do not require cooling, and the corresponding cooling time requirement is zero. Both the second oil temperature range and the second clutch temperature range are temperature ranges that require cooling, and the corresponding first cooling time is less than the second cooling time corresponding to the third oil temperature range and the third clutch temperature range. The temperature of at least one clutch includes the temperature of a first clutch and the temperature of a second clutch; The step of determining the clutch temperature range in which each clutch temperature is located includes: determining the first clutch temperature range in which the first clutch temperature is located and the second clutch temperature range in which the second clutch temperature is located.

[0013] Furthermore, obtaining the transmission oil temperature includes: Oil temperature signals are collected by an oil temperature sensor; Determine whether the oil temperature signal is valid; If the oil temperature signal is valid, then the oil temperature signal is taken as the transmission oil temperature; If the oil temperature signal is invalid, the average value of the first motor temperature and the second motor temperature minus the preset bias value is used as the alternative transmission oil temperature. The determination of whether the oil temperature signal is valid includes: Obtain the power supply voltage and feedback voltage of the oil temperature sensor; Determine whether the power supply voltage is within a first preset range and whether the feedback voltage is within a second preset range; If the power supply voltage is within the first preset range and the feedback voltage is within the second preset range, then the oil temperature signal is determined to be valid; otherwise, the oil temperature signal is determined to be invalid. If the oil temperature signal is invalid, and the signals for the first motor temperature and / or the second motor temperature are also invalid, the transmission oil temperature is forcibly regarded as being in the highest oil temperature range, and cooling is performed according to the cooling requirement time corresponding to the highest oil temperature range.

[0014] Furthermore, the step of acquiring the oil temperature signal by the oil temperature sensor includes: Oil temperature signals are acquired at a preset sampling frequency; The transmission oil temperature is determined to be in the temperature range that requires cooling only when the oil temperature signal collected for a preset number of consecutive times exceeds the corresponding temperature range threshold. The preset sampling frequency is 10ms, and the preset number of times is 15.

[0015] Furthermore, the temperature of the at least one clutch is calculated using a clutch temperature model; The clutch temperature model is calculated iteratively based on the following formula:

[0016] in, Estimate the clutch temperature for the current calculation cycle. Estimate the clutch temperature for the previous calculation cycle. The preset heating factor, The clutch torque for the current cycle. For differential rotation, The preset cooling factor, For lubricating oil flow rate, The ambient temperature for the current calculation period. This is the difference time between two calculation cycles.

[0017] Furthermore, the method also includes: When the vehicle is powered on again after being powered off, the power supply voltage, the transmission oil temperature, and the temperature of at least one clutch are reacquired, and the method is repeated to continue to provide graded cooling protection for the vehicle after power-on.

[0018] Secondly, the invention provides the following technical solution: a cooling control system for a hybrid vehicle after shutdown, the system comprising: The acquisition module is used to acquire the vehicle's power supply voltage and determine whether the power supply voltage meets the cooling enable conditions after shutdown. The module acquires the transmission oil temperature and at least one clutch temperature when the power supply voltage meets the shutdown cooling enable condition. The judgment module determines the oil temperature range of the transmission oil temperature and the clutch temperature range of each clutch temperature. The determination module determines the corresponding cooling time based on each temperature range that needs cooling, when there is at least one temperature range that needs cooling, in the oil temperature range where the transmission oil temperature is located and the clutch temperature range where the at least one clutch temperature is located. The corresponding module determines the maximum value among all cooling demand times corresponding to the temperature range that needs to be cooled as the duration of cooling after this shutdown. The control module controls the vehicle's cooling components to operate for the specified duration.

[0019] Thirdly, the invention provides the following technical solution: a computer, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the cooling control method for a hybrid vehicle after shutdown as described above.

[0020] Fourthly, the invention provides the following technical solution: a storage medium storing a computer program, which, when executed by a processor, implements the cooling control method for a hybrid vehicle after shutdown as described above. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A flowchart of a cooling control method for a hybrid vehicle after shutdown provided in the first embodiment of the present invention; Figure 2 This is a flowchart illustrating a specific application example in the first embodiment of the present invention; Figure 3 This is a structural block diagram of the cooling control system for a hybrid vehicle after shutdown, provided in the second embodiment of the present invention.

[0023] The embodiments of the present invention will be further described below with reference to the accompanying drawings. Detailed Implementation

[0024] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote elements with the same or similar data or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain embodiments of the present invention, and should not be construed as limiting the present invention.

[0025] In the description of the embodiments of the present invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present 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, they should not be construed as limitations on the present invention.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of the present invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0027] Example 1 In a first embodiment of the present invention, a cooling control method for a hybrid vehicle after shutdown is provided. This method can be applied to the vehicle controller, power domain controller, or independent cooling control unit of the hybrid vehicle.

[0028] The hybrid vehicle's powertrain includes a dedicated hybrid transmission (DHT), which integrates a generator, drive motor, first clutch, second clutch, and gear set. The vehicle's cooling system comprises an electric oil pump, an electric fan, and a coolant pump, used to circulate transmission lubricating oil, provide forced air cooling to the radiator, and circulate coolant, respectively.

[0029] like Figure 1 As shown, the cooling control method for a hybrid vehicle after shutdown in this embodiment includes the following steps S01 to S06: S01, Obtain the vehicle's power supply voltage and determine whether the power supply voltage meets the cooling enable condition after shutdown. When the vehicle is powered off, the vehicle's 12V low-voltage battery supplies power to the cooling control unit and cooling components. To avoid deep battery discharge caused by continuing cooling operations when the battery is low on charge, the current power supply voltage is first acquired and compared with the preset cooling enable conditions after shutdown.

[0030] In this embodiment, the power supply voltage is divided into three voltage ranges: a first voltage range, a second voltage range, and a third voltage range. The voltage value in the third voltage range is higher than that in the second voltage range, and the voltage value in the second voltage range is higher than that in the first voltage range. For example, the first voltage range is below 11.5V, the second voltage range is between 11.5V and 12.0V, and the third voltage range is above 12.0V. These values ​​are merely examples; in actual applications, calibration can be performed according to the battery type and vehicle strategy.

[0031] When the power supply voltage is in the first voltage range (e.g., below 11.5V), it is determined that the power supply voltage does not meet the conditions for enabling cooling after shutdown. In this case, the subsequent cooling control process will not be executed to prevent further battery discharge. When the power supply voltage is in the second or third voltage range, it is determined that the power supply voltage meets the conditions for enabling cooling after shutdown, and the subsequent cooling control is allowed to be executed.

[0032] S02, when the power supply voltage meets the shutdown cooling enable condition, obtain the transmission oil temperature and at least one clutch temperature; After confirming that the battery voltage meets the enabling conditions, the cooling control unit obtains the transmission oil temperature, the temperature of the first clutch, and the temperature of the second clutch.

[0033] The transmission fluid temperature is acquired using an oil temperature sensor. This sensor is installed in the transmission oil pan or oil passages to monitor the transmission fluid temperature in real time. To ensure the accuracy and interference resistance of the oil temperature signal, the sensor continuously samples at a frequency of 10ms. Only when 15 consecutive oil temperature signals exceed the corresponding temperature range threshold is the transmission fluid temperature determined to be within the cooling range required, effectively avoiding misjudgments caused by momentary interference.

[0034] When acquiring transmission fluid temperature, the validity of the fluid temperature signal also needs to be determined. Specifically, the fluid temperature sensor first collects the fluid temperature signal, obtaining the sensor's supply voltage and feedback voltage; then, it is determined whether the supply voltage is within a first preset range and whether the feedback voltage is within a second preset range. For example, the first preset range is 0 to 6000mV, and the second preset range is 0 to 4800mV. If the supply voltage is within the first preset range and the feedback voltage is within the second preset range, the fluid temperature signal is considered valid; otherwise, the fluid temperature signal is considered invalid.

[0035] When the oil temperature signal is valid, it is used as the transmission fluid temperature for subsequent range determination. When the oil temperature signal is invalid, the average of the first motor temperature and the second motor temperature, minus a preset bias value, is used as the alternative transmission fluid temperature. The preset bias value can be 50℃, i.e., alternative oil temperature = (first motor temperature + second motor temperature) / 2 - 50℃. This substitution strategy utilizes the thermal correlation between motor temperature and transmission fluid temperature, providing a reasonable oil temperature reference value even when the oil temperature sensor fails.

[0036] If the oil temperature signal is invalid, and the signals for the first motor temperature and / or the second motor temperature are also invalid, a reliable oil temperature reference value cannot be obtained. In this case, to ensure safety, the transmission oil temperature is forcibly treated as being in the highest oil temperature range, and cooling is performed according to the cooling requirement time corresponding to this highest oil temperature range, achieving the most stringent cooling protection.

[0037] The clutch temperature is calculated using a clutch temperature model. Since the internal temperature of the clutch is difficult to measure directly, this embodiment uses a first-order discrete iterative model to estimate the friction interface temperature of the first and second clutches. The calculation formula for the clutch temperature model is as follows:

[0038] in, Estimate the clutch temperature for the current calculation cycle. Estimate the clutch temperature for the previous calculation cycle. The preset heating factor (heat generation coefficient). The clutch torque for the current cycle. For differential rotation, The preset cooling factor (heat dissipation coefficient). For lubricating oil flow rate, The oil temperature in the sump during the current calculation period. The difference time (calculation step size) between two calculation cycles.

[0039] In the above formula, the first term The first item represents the heat generated by clutch slippage, reflecting the temperature rise caused by friction during the clutch slippage process; the second item... This indicates the cooling effect of the lubricating oil on the clutch, reflecting the temperature drop caused by the lubricating oil carrying away heat from the clutch. Through iterative calculations, the estimated temperatures of the first and second clutches can be obtained in real time.

[0040] In this embodiment, the heat generation coefficient The value can be taken as 1 / 1220 ℃ / J, heat dissipation coefficient The value can be 1 / 5.82 min / (sec·ltr). The above coefficient is an exemplary calibration value, and can be adjusted according to the specific clutch structure and lubricating oil characteristics in actual applications.

[0041] S03, determine the oil temperature range of the transmission oil temperature and the clutch temperature range of each clutch temperature; After obtaining the transmission oil temperature, the first clutch temperature, and the second clutch temperature, the temperature range in which each temperature value is located is determined.

[0042] For transmission oil temperature, this embodiment divides it into three oil temperature ranges: a first oil temperature range, a second oil temperature range, and a third oil temperature range. Among them, the first oil temperature range is the temperature range that does not require cooling, and the corresponding cooling time requirement is zero; the second oil temperature range and the third oil temperature range are both temperature ranges that require cooling, and the first cooling time requirement for the second oil temperature range is less than the second cooling time requirement for the third oil temperature range.

[0043] For example, the first oil temperature range is below 100°C, the second oil temperature range is between 100°C and 130°C, and the third oil temperature range is above 130°C. The corresponding cooling time requirements are: 0 minutes for the first oil temperature range, 3 minutes for the second oil temperature range, and 8 minutes for the third oil temperature range. The above values ​​are only examples; in actual applications, they can be calibrated according to the transmission's heat capacity, heat dissipation capacity, and lubricating oil characteristics.

[0044] The temperatures of the first and second clutches are also divided into three clutch temperature ranges: the first clutch temperature range, the second clutch temperature range, and the third clutch temperature range. The first clutch temperature range is the temperature range that does not require cooling, and its corresponding cooling time requirement is zero. Both the second and third clutch temperature ranges are temperature ranges that require cooling, and the first cooling time requirement for the second clutch temperature range is less than the second cooling time requirement for the third clutch temperature range.

[0045] For example, the first clutch temperature range is below 120°C, the second clutch temperature range is between 120°C and 160°C, and the third clutch temperature range is above 160°C. The corresponding cooling time requirements are: 0 minutes for the first clutch temperature range, 3 minutes for the second clutch temperature range, and 6 minutes for the third clutch temperature range.

[0046] It should be noted that the temperature range division of the first clutch and the second clutch can use the same threshold or different thresholds, and should be calibrated independently according to the working characteristics of each clutch.

[0047] When making the judgment, the temperature of the first clutch is determined to be within the first clutch temperature range and the temperature of the second clutch is determined to be within the second clutch temperature range.

[0048] S04, when there is at least one temperature range that needs to be cooled, and the temperature range of the transmission oil and the clutch of the at least one clutch are respectively determined according to each temperature range that needs to be cooled; After determining the temperature ranges, the cooling control unit checks if there is at least one temperature range that requires cooling. If the transmission oil temperature, the first clutch temperature, and the second clutch temperature are all within the first temperature range (i.e., none of them require cooling), it is determined that there is no cooling requirement at present, the post-shutdown cooling operation is not performed, and the process ends.

[0049] If at least one of the transmission oil temperature, the first clutch temperature, or the second clutch temperature is in the temperature range that requires cooling (i.e., the second temperature range or the third temperature range), then obtain the cooling time required for each temperature range that requires cooling.

[0050] S05, determine the maximum value among all cooling demand times corresponding to the temperature range that needs to be cooled as the duration of cooling after this shutdown; When there are multiple temperature ranges that need cooling, the maximum value of the cooling demand time corresponding to each temperature range is taken as the duration of cooling after this shutdown; when there is only one temperature range that needs cooling, the cooling demand time corresponding to that temperature range is taken as the duration.

[0051] For example, if the transmission oil temperature is in the second temperature range (cooling time required 3 minutes), the first clutch temperature is in the third clutch temperature range (cooling time required 6 minutes), and the second clutch temperature is in the first clutch temperature range (cooling time required 0 minutes), then the cooling duration will be 6 minutes. This ensures that the component with the highest heat load (the first clutch) receives sufficient cooling.

[0052] S06, control the vehicle's cooling components to operate for the specified duration.

[0053] After determining the duration, the cooling control unit sends control commands to the cooling components, causing the electric oil pump, electric fan, and cooling water pump to operate for that duration.

[0054] In this embodiment, the activation strategy for the cooling components is further refined. Based on the transmission oil temperature range and the clutch temperature range of each clutch, one or more of the electronic oil pump, electronic fan, and coolant pump are selectively activated.

[0055] Specifically, when only the transmission oil temperature is in the temperature range requiring cooling, while the temperatures of the first and second clutches are both in the temperature range not requiring cooling, only the electronic oil pump is activated to remove heat from the transmission oil pan through lubricating oil circulation; when only one clutch temperature is in the temperature range requiring cooling, the electronic oil pump and electric fan are activated to dissipate heat through lubricating oil circulation and air cooling; when both the transmission oil temperature and the temperature of any clutch are in the temperature range requiring cooling, the electronic oil pump, electric fan, and coolant pump are activated simultaneously to achieve maximum cooling capacity; when all temperatures are in the temperature range not requiring cooling, no cooling components are activated.

[0056] The above selective startup strategy is only an example. In actual applications, it can be flexibly configured according to the architecture of the cooling system and the heat dissipation requirements.

[0057] Furthermore, during the continuous operation of the cooling components, the cooling control unit monitors the power supply voltage in real time. When the power supply voltage drops below a preset safety threshold, the operation of the cooling components is immediately stopped, even if the cooling duration has not yet ended, to prevent excessive battery discharge. For example, the preset safety threshold can be 10.5V or 11.0V, specifically determined based on battery characteristics and vehicle strategy.

[0058] In this embodiment, the cooling control method described above is also executed when the vehicle is powered on again after a power outage. Specifically, after the vehicle is powered on, the cooling control unit re-acquires the power supply voltage, transmission oil temperature, and the temperatures of the first and second clutches, and executes cooling control according to the same judgment logic as after power outage. In this way, even if the vehicle temperature does not drop sufficiently during the power outage, it can still continue to perform graded cooling protection based on the current temperature range after power-on, avoiding damage to the transmission system due to excessively high temperatures in the initial stage of power-on.

[0059] In summary, the hybrid vehicle shutdown cooling control method of this invention achieves refined control of the shutdown cooling process through multiple means, such as voltage enable judgment, temperature range division, maximum cooling time determination, and selective activation of cooling components. While ensuring effective cooling, it also takes into account battery protection and reduces mechanical wear of cooling components, demonstrating significant technological progress.

[0060] In summary, a cooling control method for hybrid vehicles after shutdown has the following effects: By first obtaining the power supply voltage and determining whether the cooling enable conditions after shutdown are met, cooling will not be started when the voltage is too low. At the same time, the voltage is monitored in real time during the cooling process and the operation stops when it is below the safety threshold. This effectively avoids deep discharge of the 12V battery, prevents plate sulfation and irreversible capacity loss, and extends the battery life. By dividing the transmission oil temperature and clutch temperature into multiple temperature ranges and determining whether cooling is needed and the corresponding cooling time based on the temperature range, graded timed cooling is achieved. This overcomes the problem of long-term operation of cooling components caused by continuous cooling at a single threshold in the existing technology, reduces unnecessary mechanical wear of electronic oil pumps, electronic fans and cooling water pumps, and extends the life of cooling components. By taking the maximum cooling time from multiple temperature ranges that require cooling as the cooling duration, the components with the highest heat load are ensured to be adequately cooled, effectively preventing high-temperature oxidation of transmission fluid, accelerated aging of rubber seals, adhesion of clutch friction plates, and shortened lifespan of internal sensors and other electronic components due to prolonged high temperatures, thereby improving the reliability and durability of the transmission system. By judging the validity of the oil temperature signal and using the motor temperature as a substitute when the signal is invalid, and forcing cooling according to the highest temperature range when the motor signal is also invalid, the reliability of oil temperature acquisition and safety under fault conditions are ensured, and insufficient cooling or failure due to sensor failure is avoided.

[0061] Example 2 like Figure 2 As shown, a second embodiment of the present invention provides a cooling control system for a hybrid vehicle after it stops, the system comprising: The acquisition module 10 is used to acquire the power supply voltage of the vehicle and determine whether the power supply voltage meets the cooling enable conditions after shutdown. Module 20, when the power supply voltage meets the shutdown cooling enable condition, acquires the transmission oil temperature and at least one clutch temperature; The judgment module 30 determines the oil temperature range of the transmission oil temperature and the clutch temperature range of each clutch temperature. The determination module 40 determines the corresponding cooling time according to each temperature range that needs to be cooled, when there is at least one temperature range that needs to be cooled, in the oil temperature range where the transmission oil temperature is located and the clutch temperature range where the at least one clutch temperature is located. The corresponding module 50 determines the maximum value among all cooling demand times corresponding to the temperature range that needs to be cooled as the duration of cooling after this shutdown. The control module 60 controls the vehicle's cooling components to operate for the specified duration.

[0062] The cooling control system for hybrid vehicles after shutdown provided in this embodiment of the invention has the same implementation principle and technical effect as the aforementioned method embodiment. For the sake of brevity, any parts not mentioned in the system embodiment can be referred to the corresponding content in the aforementioned method embodiment.

[0063] Example 3 like Figure 3 As shown, in the third embodiment of the present invention, the present invention provides the following technical solution: a computer, including a memory 202, a processor 201, and a computer program stored in the memory 202 and executable on the processor 201, wherein the processor 201 executes the computer program to implement the cooling control method for a hybrid vehicle after shutdown as described above.

[0064] Specifically, the processor 201 may include a central processing unit, a specific integrated circuit, or one or more integrated circuits that can be configured to implement the embodiments of this application.

[0065] Memory 202 may include a large-capacity memory for data or instructions. For example, and not limitingly, memory 202 may include a hard disk drive, floppy disk drive, solid-state drive, flash memory, optical disk drive, magneto-optical disk drive, magnetic tape drive, or Universal Serial Bus drive, or a combination of two or more of these. Where appropriate, memory 202 may include removable or non-removable media. Where appropriate, memory 202 may be internal or external to a data processing device. In a particular embodiment, memory 202 is non-volatile memory. In a particular embodiment, memory 202 includes read-only memory and random access memory (ROM). Where appropriate, the ROM may be a mask-programmed ROM, a programmable ROM, an erasable PROM, an electrically erasable PROM, an electrically rewritable ROM, or flash memory, or a combination of two or more of these. Where appropriate, the RAM may be static random access memory (SRAM) or dynamic random access memory (DRAM), wherein DRAM may be fast page-mode DRAM, extended data output DRAM, synchronous DRAM, etc.

[0066] The memory 202 can be used to store or cache various data files that need to be processed and / or communicated, as well as possible computer program instructions executed by the processor 201.

[0067] The processor 201 reads and executes computer program instructions stored in the memory 202 to implement the above-mentioned cooling control method after the hybrid vehicle stops.

[0068] In some embodiments, the computer may further include a communication interface 203 and a bus 200. For example, Figure 3 As shown, the processor 201, memory 202, and communication interface 203 are connected through bus 200 and complete communication with each other.

[0069] The communication interface 203 is used to enable communication between the various modules, devices, units, and / or equipment in the embodiments of this application. The communication interface 203 can also enable data communication with other components such as external devices, image / data acquisition devices, databases, external storage, and image / data processing workstations.

[0070] Bus 200 includes hardware, software, or both, that couples computer components together. Bus 200 includes, but is not limited to, at least one of the following: data bus, address bus, control bus, expansion bus, local bus. For example, and not limitingly, bus 200 may include a graphics acceleration interface or other graphics bus, an enhanced industry standard architecture bus, a front-side bus, HyperTransport interconnect, an industry standard architecture bus, a wireless bandwidth interconnect, a low pin count bus, a memory bus, a WeChat architecture bus, a peripheral component interconnect bus, a PCI Express bus, a Serial Advanced Technology Attached Bus, a Video Electronics Standards Association local bus, or other suitable buses, or combinations of two or more of these. Where appropriate, bus 200 may include one or more buses. Although specific buses are described and illustrated in embodiments of this application, this application contemplates any suitable bus or interconnect.

[0071] Example 4 In the fourth embodiment of the present invention, in conjunction with the above-described cooling control method for hybrid vehicles after shutdown, the present invention provides the following technical solution: a storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the above-described cooling control method for hybrid vehicles after shutdown.

[0072] Those skilled in the art will understand that the data in the flowchart, or the logic and / or steps otherwise described herein, can be considered, for example, a sequence of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device. For the purposes of this specification, "computer-readable medium" can mean any means that can contain, store, communicate, propagate, or transmit a program for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0073] More specific examples of readable media include: electrical connections having one or more wires, portable computer disk drives, random access memory, read-only memory, erasable programmable read-only memory, fiber optic devices, and portable optical disc read-only memory. Additionally, computer-readable media can even be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0074] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (FPGAs), field-programmable gate arrays (FPGAs), etc.

[0075] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0076] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A cooling control method after shutdown of a hybrid vehicle, characterized by, The method includes: Obtain the vehicle's power supply voltage and determine whether the power supply voltage meets the cooling enable conditions after shutdown. When the power supply voltage meets the shutdown cooling enable condition, the transmission oil temperature and at least one clutch temperature are obtained. Determine the oil temperature range of the transmission fluid and the clutch temperature range of each clutch. When there is at least one temperature range that requires cooling, between the oil temperature range where the transmission oil temperature is located and the clutch temperature range where the at least one clutch temperature is located, the corresponding cooling time is determined according to each temperature range that requires cooling. The maximum value among all cooling time requirements corresponding to the temperature range that needs to be cooled is determined as the duration of cooling after this shutdown; The vehicle's cooling components are controlled to operate for the specified duration.

2. The cooling control method for a hybrid vehicle after shutdown according to claim 1, characterized in that, The shutdown cooling enable condition includes: dividing the power supply voltage into at least one of multiple voltage ranges; The plurality of voltage ranges includes a first voltage range, a second voltage range, and a third voltage range; When the power supply voltage is in the first voltage range, the cooling enable condition after shutdown is not met; when the power supply voltage is in the second voltage range or the third voltage range, the cooling enable condition after shutdown is met. The voltage value in the third voltage range is higher than the voltage value in the second voltage range.

3. The cooling control method for a hybrid vehicle after shutdown according to claim 1, characterized in that, The transmission oil temperature range includes a first oil temperature range, a second oil temperature range, and a third oil temperature range, and the clutch temperature range includes a first clutch temperature range, a second clutch temperature range, and a third clutch temperature range. Both the first oil temperature range and the first clutch temperature range are temperature ranges that do not require cooling, and the corresponding cooling time requirement is zero. Both the second oil temperature range and the second clutch temperature range are temperature ranges that require cooling, and the corresponding first cooling time is less than the second cooling time corresponding to the third oil temperature range and the third clutch temperature range. The temperature of at least one clutch includes the temperature of a first clutch and the temperature of a second clutch; The step of determining the clutch temperature range in which each clutch temperature is located includes: determining the first clutch temperature range in which the first clutch temperature is located and the second clutch temperature range in which the second clutch temperature is located.

4. The cooling control method for a hybrid vehicle after shutdown according to claim 1, characterized in that, The process of obtaining the transmission oil temperature includes: Oil temperature signals are collected by an oil temperature sensor; Determine whether the oil temperature signal is valid; If the oil temperature signal is valid, then the oil temperature signal is taken as the transmission oil temperature; If the oil temperature signal is invalid, the average value of the first motor temperature and the second motor temperature minus the preset bias value is used as the alternative transmission oil temperature. The determination of whether the oil temperature signal is valid includes: Obtain the power supply voltage and feedback voltage of the oil temperature sensor; Determine whether the power supply voltage is within a first preset range and whether the feedback voltage is within a second preset range; If the power supply voltage is within the first preset range and the feedback voltage is within the second preset range, then the oil temperature signal is determined to be valid; otherwise, the oil temperature signal is determined to be invalid. If the oil temperature signal is invalid, and the signals for the first motor temperature and / or the second motor temperature are also invalid, the transmission oil temperature is forcibly regarded as being in the highest oil temperature range, and cooling is performed according to the cooling requirement time corresponding to the highest oil temperature range.

5. The cooling control method for a hybrid vehicle after shutdown according to claim 4, characterized in that, The step of acquiring the oil temperature signal by the oil temperature sensor includes: Oil temperature signals are acquired at a preset sampling frequency; The transmission oil temperature is determined to be in the temperature range that requires cooling only when the oil temperature signal collected for a preset number of consecutive times exceeds the corresponding temperature range threshold.

6. The cooling control method for a hybrid vehicle after shutdown according to claim 1, characterized in that, The temperature of the at least one clutch is obtained by calculation using a clutch temperature model; The clutch temperature model is calculated iteratively based on the following formula: in, Estimate the clutch temperature for the current calculation cycle. Estimate the clutch temperature for the previous calculation cycle. The preset heating factor, The clutch torque for the current cycle. For differential rotation, The preset cooling factor, For lubricating oil flow rate, The ambient temperature for the current calculation period. This is the difference time between two calculation cycles.

7. The cooling control method for a hybrid vehicle after shutdown according to claim 1, characterized in that, The method further includes: When the vehicle is powered on again after being powered off, the power supply voltage, the transmission oil temperature, and the temperature of at least one clutch are reacquired, and the method is repeated to continue to provide graded cooling protection for the vehicle after power-on.

8. A cooling control system for a hybrid vehicle after shutdown, characterized in that, The system includes: The acquisition module is used to acquire the vehicle's power supply voltage and determine whether the power supply voltage meets the cooling enable conditions after shutdown. The module acquires the transmission oil temperature and at least one clutch temperature when the power supply voltage meets the shutdown cooling enable condition. The judgment module determines the oil temperature range of the transmission oil temperature and the clutch temperature range of each clutch temperature. The determination module determines the corresponding cooling time based on each temperature range that needs cooling, when there is at least one temperature range that needs cooling, in the oil temperature range where the transmission oil temperature is located and the clutch temperature range where the at least one clutch temperature is located. The corresponding module determines the maximum value among all cooling demand times corresponding to the temperature range that needs to be cooled as the duration of cooling after this shutdown. The control module controls the vehicle's cooling components to operate for the specified duration.

9. A computer comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the cooling control method for a hybrid vehicle after shutdown as described in any one of claims 1 to 7.

10. A storage medium, characterized in that, The storage medium stores a computer program, which, when executed by a processor, implements the cooling control method for a hybrid vehicle after shutdown as described in any one of claims 1 to 7.

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