Method and equipment for estimating temperature of cooling liquid
By determining the estimation mode under the vehicle and engine operating conditions and calculating the coolant temperature change based on multiple factors, the problems of high cost and low accuracy in the existing technology are solved, and accurate coolant temperature estimation and cost reduction are achieved.
Patent Information
- Application Number
- CN202511011662.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-22
- Publication Date
- 2025-10-17
AI Technical Summary
In the prior art, the solution of using a primary water temperature sensor and a secondary water temperature sensor to measure the coolant temperature increases vehicle cost and is difficult to accurately estimate the coolant temperature under complex engine operating conditions.
By determining the estimation mode according to the operating status of the vehicle and engine, and combining factors such as ambient temperature, vehicle speed, and intake air flow, the basic value and correction value of the coolant temperature change are calculated, reducing dependence on the water temperature sensor.
It achieves accurate estimation of coolant temperature under different operating conditions, reduces vehicle costs, and allows safe driving to the maintenance station even when the main water temperature sensor fails, improving the accuracy of coolant temperature estimation.
Smart Images
Figure CN120798513A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of vehicle control, and particularly relates to a cooling liquid temperature estimation method and device. BACKGROUND
[0002] The temperature of the cooling liquid in the cooling circuit of the engine is an important parameter reflecting the working thermal state of the engine, and directly affects the normal operation, performance and service life of the engine.
[0003] In the related art, the temperature of the cooling liquid in the cooling circuit of the engine is usually measured by a main water temperature sensor, and a secondary water temperature sensor is arranged at the inlet of the radiator to check the temperature of the cooling liquid by the secondary water temperature sensor, so as to determine whether the temperature measured by the main water temperature sensor is accurate. This scheme needs to add a secondary water temperature sensor, resulting in high vehicle cost. SUMMARY
[0004] Embodiments of the application provide a cooling liquid temperature estimation method and device, which can accurately estimate the cooling liquid temperature of the cooling liquid in the cooling circuit of the engine to at least some extent, so as to reduce the water temperature sensor and reduce the vehicle cost.
[0005] Other characteristics and advantages of the application will become apparent from the following detailed description, or will be learned by practice of the application.
[0006] According to a first aspect of an embodiment of the application, a cooling liquid temperature estimation method is provided, applied to a vehicle, the vehicle comprising an engine and a cooling circuit, the cooling circuit comprising a cooling liquid, the cooling circuit being used for cooling the engine, and the estimation method comprising:
[0007] determining an estimation mode of a current cooling liquid temperature according to an operating state of the vehicle and an operating state of the engine;
[0008] determining a temperature change basic value of the current cooling liquid temperature according to the estimation mode;
[0009] determining a temperature change correction value of the current cooling liquid temperature according to the temperature change basic value, a temperature adjustment coefficient and a cooling compensation value;
[0010] in a case where a target estimation value of the current cooling liquid temperature needs to be reset, determining the target estimation value of the current cooling liquid temperature as a sum of the temperature change correction value and a last cooling liquid temperature target estimation value.
[0011] In some embodiments, the running state of the vehicle includes a first state for representing that the vehicle is running and a second state for representing that the vehicle is not running, the running state of the engine includes a third state for representing that the engine is running and a fourth state for representing that the engine is not running, and the estimation mode of the current coolant temperature is determined according to the running state of the vehicle and the running state of the engine, including:
[0012] In a case where the running state of the vehicle is the first state and the running state of the engine is the fourth state, the estimation mode of the current coolant temperature is determined as the first mode.
[0013] In a case where the running state of the vehicle is the first state and the running state of the engine is the third state, the estimation mode of the current coolant temperature is determined as the second mode.
[0014] In a case where the running state of the vehicle is the second state and the running state of the engine is the third state, the estimation mode of the current coolant temperature is determined as the third mode.
[0015] In a case where the running state of the vehicle is the second state and the running state of the engine is the fourth state, the estimation mode of the current coolant temperature is determined as the fourth mode.
[0016] In some embodiments, the temperature change base value of the current coolant temperature is determined according to the estimation mode, including:
[0017] In a case where the estimation mode is the first mode, the temperature change base value of the current coolant temperature is determined according to an ambient temperature of an environment in which the vehicle is located, a motor power, and a vehicle speed.
[0018] In some embodiments, the temperature change base value of the current coolant temperature is determined according to the estimation mode, including:
[0019] In a case where the estimation mode is the second mode, the temperature change base value of the current coolant temperature is determined according to an ambient temperature of an environment in which the vehicle is located, an intake flow rate of the engine, and a vehicle speed.
[0020] In some embodiments, the temperature change base value of the current coolant temperature is determined according to the estimation mode, including:
[0021] In a case where the estimation mode is the third mode, the temperature change base value of the current coolant temperature is determined according to an ambient temperature of an environment in which the vehicle is located and an intake flow rate of the engine.
[0022] In some embodiments, the temperature change base value of the current coolant temperature is determined according to the estimation mode, including:
[0023] In a case where the estimation mode is the fourth mode, a temperature change base value of the current coolant temperature is determined according to an ambient temperature of an environment in which the vehicle is located and a stop duration of the engine.
[0024] In some embodiments, a temperature change correction value of the current coolant temperature is determined according to the temperature change base value, a temperature adjustment coefficient and a cooling compensation value, including:
[0025] A product of the temperature change base value and the temperature adjustment coefficient is added to the cooling compensation value to obtain the temperature change correction value of the current coolant temperature.
[0026] In some embodiments, the cooling circuit further includes a fan and a thermostat, and before the temperature change correction value of the current coolant temperature is determined according to the temperature change base value, the temperature adjustment coefficient and the cooling compensation value, the estimation method further includes:
[0027] The temperature adjustment coefficient is determined according to the ambient temperature of the environment in which the vehicle is located and the temperature change base value;
[0028] The cooling compensation value is determined according to the ambient temperature, a speed percentage of the fan and an opening percentage of the thermostat.
[0029] In some embodiments, before the target estimation value of the current coolant temperature is determined as a sum of the temperature change correction value and the target estimation value of the last coolant temperature in a case where the target estimation value of the current coolant temperature needs to be reset, the estimation method further includes:
[0030] If the engine is not running for more than a first preset duration after the vehicle is powered off, or the vehicle is running in a pure electric mode and the engine is not running for more than a second preset duration, it is determined that the target estimation value of the current coolant temperature needs to be reset.
[0031] According to a second aspect of the embodiments of the present application, a coolant temperature estimation device is provided, including a processor and a memory, the memory storing computer program instructions capable of being executed by the processor, and the processor implements the steps of the method of any one of the above first aspect when executing the computer program instructions.
[0032] In the present application, an estimation mode of a current coolant temperature is determined according to an operating state of a vehicle and an operating state of an engine; a temperature change base value of the current coolant temperature is determined according to the estimation mode; a temperature change correction value of the current coolant temperature is determined according to the temperature change base value, a temperature adjustment coefficient and a cooling compensation value; and in a case where a target estimation value of the current coolant temperature needs to be reset, the target estimation value of the current coolant temperature is determined as a sum of the temperature change correction value and a target estimation value of a last coolant temperature. The above scheme can accurately estimate the coolant temperature, so as to reduce the water temperature sensor and reduce the cost of the vehicle.
[0033] It should be understood that the general description and detailed description below are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF DRAWINGS
[0034] The drawings incorporated in the specification include exemplary embodiments in accordance with the present application and, together with the specification, serve to explain the principles of the present application. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings. In the drawings:
[0035] Figure 1 An electrical architecture diagram of a vehicle according to some embodiments of the present application is shown;
[0036] Figure 2 A flowchart of an estimation method of coolant temperature according to some embodiments of the present application is shown;
[0037] Figure 3 A block diagram of an estimation device of coolant temperature according to some embodiments of the present application is shown;
[0038] Figure 4 A structural diagram of an estimation device of coolant temperature according to some embodiments of the present application is shown;
[0039] Explanation of reference signs:
[0040] 101 - engine; 102 - cooling circuit; 103 - generator; 104 - drive motor; 105 - battery; 106 - wheel; 107 - thermostat; 108 - fan; 109 - radiator. DETAILED DESCRIPTION
[0041] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.
[0042] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner.In the following description, many specific details are provided so as to provide a full understanding of the embodiments of the present application. However, it will be appreciated by those skilled in the art that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps etc. can be adopted. In other cases, known methods, devices, implementations or operations are not shown or described in detail to avoid blurring the various aspects of the application.
[0043] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically separate entities. That is, these functional entities may be implemented in software, in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.
[0044] The flowcharts shown in the accompanying drawings are for illustrative purposes only and do not necessarily include all contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may be decomposed, while others may be combined or partially combined. Therefore, the actual execution order may vary depending on the actual situation.
[0045] In order to make those skilled in the art better understand this application, first combine Figure 1 A brief description is given of the electrical architecture and application scenarios of the vehicle involved in this application.
[0046] like Figure 1 As shown, the vehicle includes an engine 101 and a cooling circuit 102. The cooling circuit includes a coolant (not shown) and is used to cool the engine 101. In some embodiments, the vehicle may further include a generator 103, a drive motor 104, a battery 105, and wheels 106. The cooling circuit may further include a thermostat 107, a fan 108, and a radiator 109. The thermostat 107 is used to adjust the circulation path and flow rate of the coolant to ensure that the engine 101 quickly reaches and stabilizes at an optimal operating temperature.
[0047] In a related technology, a main water temperature sensor is usually used to measure the temperature of the coolant in the engine's cooling circuit, and a secondary water temperature sensor is set at the radiator inlet. The secondary water temperature sensor is used to verify the coolant temperature and then determine whether the temperature measured by the main water temperature sensor is accurate. This solution requires the addition of a secondary water temperature sensor, resulting in higher vehicle costs.
[0048] In another related technology, after the engine is first started, the measured signal from the main water temperature sensor is used as the starting temperature for coolant temperature estimation. The temperature rise or fall gradient is then determined based on the engine runtime, ambient temperature, vehicle speed, and vehicle load. This temperature gradient is continuously accumulated on the starting temperature to produce an estimated coolant temperature value at each moment. After the engine is shut down, the measured signal from the main water temperature sensor is directly used as the coolant temperature estimate. In hybrid vehicles, the engine may shut down repeatedly, resulting in a rough estimate or cessation of the estimate after shutdown, which can result in significant errors. Therefore, this solution struggles to accurately estimate the coolant temperature under all operating conditions. Furthermore, the operating conditions during engine operation are complex, and this solution cannot be refined to every operating point, making the coolant temperature estimate susceptible to significant errors.
[0049] The solution adopted in this application is as follows: determining a current coolant temperature estimation mode based on the vehicle's operating state and the engine's operating state; determining a base temperature change value for the current coolant temperature based on the estimation mode; determining a temperature change correction value for the current coolant temperature based on the base temperature change value, the temperature adjustment coefficient, and the cooling compensation value; and determining the current target coolant temperature estimate as the sum of the temperature change correction value and the previous target coolant temperature estimate when the current target coolant temperature estimate needs to be reset. On the one hand, this solution can replace the auxiliary water temperature sensor to quickly and accurately estimate the coolant temperature, reducing vehicle costs. Even if the main water temperature sensor fails, it can continue to provide coolant temperature information, ensuring that the vehicle can safely reach the repair station and receive timely repairs. On the other hand, by designing different estimation modes, this solution can ensure accurate coolant temperature estimation at every operating point (e.g., when the engine is not running), adapt to repeated switching between hybrid and pure electric operating modes, and comprehensively improve the accuracy of coolant temperature estimation.
[0050] Figure 2 FIG. 1 is a flow chart of a method for estimating the coolant temperature according to some embodiments of the present application. Figure 2 As shown, a method for estimating the coolant temperature is provided, which can be applied to Figure 1 For the vehicle shown in , the method may include the following steps 201 to 204.
[0051] In step 201 , a current coolant temperature estimation mode is determined according to the vehicle operating state and the engine operating state.
[0052] The running state of the vehicle includes a first state for characterizing that the vehicle is running and a second state for characterizing that the vehicle is not running, and the running state of the engine includes a third state for characterizing that the engine is running and a fourth state for characterizing that the engine is not running.
[0053] In some embodiments, the estimation mode of the current coolant temperature can be determined as the first mode when the running state of the vehicle is the first state and the running state of the engine is the fourth state; the estimation mode of the current coolant temperature can be determined as the second mode when the running state of the vehicle is the first state and the running state of the engine is the third state; the estimation mode of the current coolant temperature can be determined as the third mode when the running state of the vehicle is the second state and the running state of the engine is the third state; and the estimation mode of the current coolant temperature can be determined as the fourth mode when the running state of the vehicle is the second state and the running state of the engine is the fourth state.
[0054] It can be understood that the estimation mode can be determined as the first mode when the vehicle is running and the engine is not running, such as a pure electric driving condition of the vehicle; the estimation mode can be determined as the second mode when the vehicle is running and the engine is running, such as a hybrid driving condition or a fuel driving condition; the estimation mode can be determined as the third mode when the vehicle is not running and the engine is running, such as an idling power generation condition; and the estimation mode can be determined as the fourth mode when the vehicle is not running and the engine is not running, such as a parking condition or a condition after the vehicle is powered off.
[0055] By determining the estimation mode of the current coolant temperature according to the running state of the vehicle and the running state of the engine, the estimation mode of all working conditions can be determined, and thus the coolant temperature of each working condition can be estimated.
[0056] In step 202, a temperature change basic value of the current coolant temperature is determined according to the estimation mode.
[0057] It can be understood that the influencing factors of the change of the coolant temperature are different for different estimation modes, and thus the corresponding temperature change basic values are also different. The corresponding temperature change basic value can be determined in combination with the estimation mode and the influencing factors of the change of the coolant temperature (for example, the ambient temperature of the environment in which the vehicle is located, the vehicle speed, etc.).
[0058] In some embodiments, when the estimation mode is the first mode, the temperature change basic value of the current coolant temperature is determined according to the ambient temperature of the environment in which the vehicle is located, the motor power and the vehicle speed.
[0059] It can be understood that the coolant temperature can represent the engine temperature, when the estimation mode is the first mode, the change of the engine temperature is mainly affected by the driving wind speed, the ambient temperature and the nacelle temperature; the nacelle temperature is mainly from the heat radiation of the motor, and the heat radiation of the motor is closely related to the motor power, and the driving wind speed can be represented by the vehicle speed, therefore, the following three-dimensional tables MAP1-1 and MAP1-2 can be defined, the values of MAP1-1 and MAP1-2 are obtained by looking up the tables respectively and added, to obtain the temperature change basic value of the current coolant temperature corresponding to the first mode.
[0060] Table MAP1-1
[0061]
[0062] Table MAP1-2
[0063]
[0064] In some embodiments, in the case that the estimation mode is the second mode, the temperature change basic value of the current coolant temperature is determined according to the ambient temperature of the environment where the vehicle is located, the intake flow of the engine and the vehicle speed.
[0065] It can be understood that the coolant temperature can represent the engine temperature, when the estimation mode is the second mode, the change of the engine temperature is mainly affected by the wind speed, the ambient temperature and the engine running heat release; the engine running heat release is related to the engine load, and the engine load can be represented by the intake flow, and the driving wind speed can be represented by the vehicle speed, therefore, the following three-dimensional tables MAP2-1 and MAP2-2 can be defined, the values of MAP2-1 and MAP2-2 are obtained by looking up the tables respectively and added, to obtain the temperature change basic value of the current coolant temperature corresponding to the second mode.
[0066] Table MAP2-1
[0067]
[0068]
[0069] Table MAP2-2
[0070]
[0071] In some embodiments, in the case that the estimation mode is the third mode, the temperature change basic value of the current coolant temperature is determined according to the ambient temperature of the environment where the vehicle is located and the intake flow of the engine.
[0072] It can be understood that the coolant temperature can represent the engine temperature, when the estimation mode is the third mode, the change of the engine temperature is mainly affected by the ambient temperature and the engine running heat release; the engine running heat release is related to the engine load, and the engine load can be represented by the intake air flow, therefore, the following three-dimensional table MAP3 can be defined, and the temperature change base value corresponding to the third mode is obtained by table lookup.
[0073] Table MAP3
[0074]
[0075] In some embodiments, when the estimation mode is the fourth mode, a temperature change base value of the current coolant temperature is determined according to the ambient temperature of the environment where the vehicle is located and the shutdown duration of the engine.
[0076] It can be understood that the coolant temperature can represent the engine temperature, when the estimation mode is the fourth mode, the change of the engine temperature is mainly affected by the ambient temperature and the shutdown duration; therefore, the following three-dimensional table MAP4 can be defined, and the temperature change base value corresponding to the fourth mode is obtained by table lookup.
[0077] Table MAP4
[0078]
[0079]
[0080] In step 203, a temperature change correction value of the current coolant temperature is determined according to the temperature change base value, the temperature adjustment coefficient and the cooling compensation value.
[0081] The temperature adjustment coefficient is related to the ambient temperature and the current estimated temperature change base value, and the change rule of the coolant temperature is first steeply rising and then slowly rising, and the temperature adjustment coefficient will continuously decrease with the continuous increase of the coolant temperature. Therefore, the following three-dimensional table MAP5 can be defined, and the temperature adjustment coefficient is obtained by table lookup.
[0082] Table MAP5
[0083]
[0084]
[0085] When the vehicle is coasting and the engine is in the fuel cut condition, the temperature adjustment coefficient is set to 0.
[0086] In some embodiments, the cooling circuit further comprises a fan and a thermostat, and before determining the temperature change correction value of the current coolant temperature according to the temperature change base value, the temperature adjustment coefficient and the cooling compensation value, the temperature adjustment coefficient can be determined according to the ambient temperature of the environment in which the vehicle is located and the temperature change base value; and the cooling compensation value can be determined according to the ambient temperature, the rotation speed percentage of the fan and the opening percentage of the thermostat.
[0087] It can be understood that there are two circulation paths of the coolant: one is small circulation: when cold starting, the thermostat is closed, and the coolant only circulates in the engine; and the other is large circulation: when the coolant temperature reaches a set value, the thermostat is opened, and the coolant flows through the radiator for heat dissipation.
[0088] When the large circulation is opened, the circulation of the coolant and the operation of the fan will take away heat, causing the coolant temperature to decrease, and the degree of decrease of the coolant temperature is related to the ambient temperature, the rotation speed percentage of the fan and the opening percentage of the thermostat. Therefore, the following three-dimensional tables MAP6-1 and MAP6-2 can be defined, the values of MAP6-1 and MA6-2 are obtained by looking up the tables respectively and added, and the cooling compensation value when the large circulation is opened is obtained.
[0089] Table MAP6-1
[0090]
[0091] Table MAP6-2
[0092]
[0093] In some embodiments, the temperature change correction value of the current coolant temperature can be obtained by adding the product of the temperature change base value and the temperature adjustment coefficient and the cooling compensation value.
[0094] The temperature change correction value can be calculated by the following formula:
[0095] G T1 = G Tb × a + G b ;
[0096] wherein, G T1 is the temperature change correction value, G Tb is the temperature change base value, a is the temperature adjustment coefficient, and G b is the cooling compensation value.
[0097] By correcting the temperature change base value by using the temperature adjustment coefficient and the cooling compensation value, the temperature change correction value obtained can more accurately reflect the actual change amount of the coolant temperature.
[0098] In step 204, if the target estimated value of the current coolant temperature needs to be reset, the sum of the temperature change correction value and the target estimated value of the last coolant temperature is determined as the target estimated value of the current coolant temperature.
[0099] It can be understood that if the target estimated value of the current coolant temperature needs to be reset, the target estimated value of the last coolant temperature needs to be updated as the target estimated value of the current coolant temperature; if the target estimated value of the current coolant temperature does not need to be reset, the target estimated value of the last coolant temperature is still displayed.
[0100] In some embodiments, if the vehicle is powered off, the engine is not running for more than a first preset time length, or the vehicle is running in a pure electric mode and the engine is not running for more than a second preset time length, it is determined that the target estimated value of the current coolant temperature needs to be reset.
[0101] The first preset time length and the second preset time length can be calibrated according to specific conditions, and the embodiments of the present application do not limit this.
[0102] When any of the above two conditions is met, it can be determined that the target estimated value of the current coolant temperature needs to be reset. When the vehicle is powered on again, since there is no target estimated value of the last coolant temperature, the coolant temperature detected by the water temperature sensor can be taken as the initial target estimated value.
[0103] The embodiments of the present application determine the estimation mode of the current coolant temperature according to the running state of the vehicle and the running state of the engine; determine the temperature change base value of the current coolant temperature according to the estimation mode; determine the temperature change correction value of the current coolant temperature according to the temperature change base value, the temperature adjustment coefficient and the cooling compensation value; and in the case that the target estimated value of the current coolant temperature needs to be reset, the sum of the temperature change correction value and the target estimated value of the last coolant temperature is determined as the target estimated value of the current coolant temperature. The above scheme can accurately estimate the coolant temperature, so as to reduce the water temperature sensor and reduce the cost of the vehicle.
[0104] The device embodiments of the present application are introduced below, which can be used to execute the coolant temperature estimation method in the above embodiments of the present application. For details not disclosed in the device embodiments of the present application, please refer to the above embodiments of the coolant temperature estimation method.
[0105] Referring to Figure 3 , a block diagram of a coolant temperature estimation device in the embodiments of the present application is shown.
[0106] As Figure 3As shown, the cooling liquid temperature estimation device of the embodiment of the present application is applied to a vehicle, the vehicle comprising an engine and a cooling circuit, the cooling circuit comprising a cooling liquid, and the cooling circuit being used for cooling the engine, the device comprising: an estimation mode determination module 301, a temperature change basic value determination module 302, a temperature change basic value correction module 303, and a target estimation value determination module 304, wherein the estimation mode determination module 301 is configured to determine an estimation mode of a current cooling liquid temperature according to an operating state of the vehicle and an operating state of the engine; the temperature change basic value determination module 302 is configured to determine a temperature change basic value of the current cooling liquid temperature according to the estimation mode; the temperature change basic value correction module 303 is configured to determine a temperature change correction value of the current cooling liquid temperature according to the temperature change basic value, a temperature adjustment coefficient, and a cooling compensation value; and the target estimation value determination module 304 is configured to determine a target estimation value of the current cooling liquid temperature as a sum of the temperature change correction value and a target estimation value of a previous cooling liquid temperature in a case where the target estimation value of the current cooling liquid temperature needs to be reset.
[0107] In some embodiments, based on the foregoing scheme, the operating state of the vehicle comprises a first state for representing that the vehicle is running and a second state for representing that the vehicle is not running, the operating state of the engine comprises a third state for representing that the engine is running and a fourth state for representing that the engine is not running, and the estimation mode determination module 301 is further configured to determine the estimation mode of the current cooling liquid temperature as a first mode in a case where the operating state of the vehicle is the first state and the operating state of the engine is the fourth state, determine the estimation mode of the current cooling liquid temperature as a second mode in a case where the operating state of the vehicle is the first state and the operating state of the engine is the third state, determine the estimation mode of the current cooling liquid temperature as a third mode in a case where the operating state of the vehicle is the second state and the operating state of the engine is the third state, and determine the estimation mode of the current cooling liquid temperature as a fourth mode in a case where the operating state of the vehicle is the second state and the operating state of the engine is the fourth state.
[0108] In some embodiments, based on the foregoing scheme, the temperature change basic value determination module 302 is further configured to determine the temperature change basic value of the current cooling liquid temperature according to an ambient temperature of an environment in which the vehicle is located, a motor power, and a vehicle speed in a case where the estimation mode is the first mode.
[0109] In some embodiments, based on the foregoing scheme, the temperature change basic value determination module 302 is further configured to determine the temperature change basic value of the current cooling liquid temperature according to an ambient temperature of an environment in which the vehicle is located, an intake flow of the engine, and a vehicle speed in a case where the estimation mode is the second mode.
[0110] In some embodiments, based on the foregoing scheme, the temperature change basic value determination module 302 is further configured to, when the estimation mode is the third mode, determine the temperature change basic value of the current coolant temperature according to the ambient temperature of the environment in which the vehicle is located and the intake flow of the engine.
[0111] In some embodiments, based on the foregoing scheme, the temperature change basic value determination module 302 is further configured to, when the estimation mode is the fourth mode, determine the temperature change basic value of the current coolant temperature according to the ambient temperature of the environment in which the vehicle is located and the shutdown duration of the engine.
[0112] In some embodiments, based on the foregoing scheme, the temperature change basic value correction module 303 is further configured to obtain the temperature change correction value of the current coolant temperature by multiplying the temperature change basic value by the temperature adjustment coefficient and adding the cooling compensation value.
[0113] In some embodiments, based on the foregoing scheme, the temperature change basic value correction module 303 is further configured to determine the temperature adjustment coefficient according to the ambient temperature of the environment in which the vehicle is located and the temperature change basic value, and determine the cooling compensation value according to the ambient temperature, the rotation speed percentage of the fan and the opening percentage of the thermostat.
[0114] In some embodiments, based on the foregoing scheme, the target estimation value determination module 304 is further configured to determine that the target estimation value of the current coolant temperature needs to be reset if the engine has not been running for more than a first preset duration after the vehicle is powered off, or the vehicle is running in the pure electric mode and the engine has not been running for more than a second preset duration.
[0115] Based on the same inventive concept, the embodiments of the present application also provide a coolant temperature estimation device. Referring to Figure 4 , a structural schematic diagram of the coolant temperature estimation device in the embodiments of the present application is shown, the coolant temperature estimation device comprises one or more memories 404, one or more processors 402, and at least one computer program (computer program instructions) stored in the memory 404 and executable on the processor 402, and the processor 402 implements the method as described above when executing the computer program.
[0116] In some embodiments, based on the foregoing scheme, the temperature change basic value determination module 302 is further configured to, when the estimation mode is the third mode, determine the temperature change basic value of the current coolant temperature according to the ambient temperature of the environment in which the vehicle is located and the intake flow of the engine. Figure 4In the embodiment of the present invention, a bus architecture (represented by bus 400) is shown. Bus 400 may include any number of interconnected buses and bridges, and bus 400 links together various circuits including one or more processors represented by processor 402 and memory represented by memory 404. Bus 400 may also link together various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and therefore will not be described further herein. Bus interface 405 provides an interface between bus 400 and receiver 401 and transmitter 403. Receiver 401 and transmitter 403 may be the same component, namely a transceiver, which provides a unit for communicating with various other devices over a transmission medium. Processor 402 is responsible for managing bus 400 and general processing, while memory 404 may be used to store data used by processor 402 when performing operations.
[0117] Based on the same inventive concept, an embodiment of the present application provides a computer-readable storage medium, in which computer program instructions are stored. When the computer program instructions are executed by a processor, the processor is prompted to implement the steps of the method as described above.
[0118] Based on the same inventive concept, an embodiment of the present application provides a computer program product, including a computer program. When the computer program product is executed by a processor, it prompts the processor to implement the steps of the method described above.
[0119] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored as one or more instructions or codes on or transmitted via a computer-readable medium. Other examples and implementations are within the scope and spirit of this application and the appended claims. For example, due to the nature of software, the functions described above may be implemented using software executed by a processor, hardware, firmware, hardwiring, or a combination of any of these. Furthermore, the functional units may be integrated into a single processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit.
[0120] In several embodiments provided in the present application, it should be understood that the disclosed technology can be implemented in other ways. Among them, the above-mentioned device embodiments are only schematic, for example, the division of the units can be a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed each other can be through some interface, indirect coupling or communication connection between units or modules, which can be electrical or other forms.
[0121] The units described as separate components can or can not be physically separated, and the components of the control device can or can not be physical units, i.e. can be located in one place or can be distributed to multiple units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.
[0122] The integrated unit, if implemented in the form of a software function unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a plurality of instructions for making a computer device (which can be a personal computer, a server or a network device, etc.) execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: a U disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a mobile hard disk, a magnetic disk or an optical disk, and various computer program instruction storage media.
[0123] The above is only an embodiment of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the scope of claims of the present application.
Claims
1. A method for estimating coolant temperature, characterized in that: Applied to a vehicle, the vehicle includes an engine and a cooling circuit, the cooling circuit includes a coolant, and the cooling circuit is used to cool the engine. The estimation method includes: determining an estimation mode of a current coolant temperature according to an operating state of the vehicle and an operating state of the engine; determining a temperature change base value of the current coolant temperature according to the estimation mode; Determining a temperature change correction value of the current coolant temperature based on the temperature change base value, the temperature adjustment coefficient, and the cooling compensation value; When the current target estimated value of the coolant temperature needs to be reset, the sum of the temperature change correction value and the previous target estimated value of the coolant temperature is determined as the current target estimated value of the coolant temperature.
2. The method for estimating the coolant temperature according to claim 1, wherein: The vehicle operating state includes a first state for indicating that the vehicle is operating and a second state for indicating that the vehicle is not operating. The engine operating state includes a third state for indicating that the engine is operating and a fourth state for indicating that the engine is not operating. The estimating mode for determining the current coolant temperature based on the vehicle operating state and the engine operating state includes: When the operating state of the vehicle is the first state and the operating state of the engine is the fourth state, determining that the current coolant temperature estimation mode is the first mode; When the operating state of the vehicle is the first state and the operating state of the engine is the third state, determining that the current coolant temperature estimation mode is the second mode; When the operating state of the vehicle is the second state and the operating state of the engine is the third state, determining that the current coolant temperature estimation mode is the third mode; When the operating state of the vehicle is the second state and the operating state of the engine is the fourth state, the current coolant temperature estimation mode is determined to be the fourth mode.
3. The method for estimating the coolant temperature according to claim 2, wherein: Determining the temperature change base value of the current coolant temperature according to the estimation mode includes: When the estimation mode is the first mode, a temperature change base value of the current coolant temperature is determined according to the ambient temperature, motor power, and vehicle speed of the environment in which the vehicle is located.
4. The method for estimating the coolant temperature according to claim 2, wherein: Determining the temperature change base value of the current coolant temperature according to the estimation mode includes: When the estimation mode is the second mode, a temperature change base value of the current coolant temperature is determined according to the ambient temperature of the environment in which the vehicle is located, the intake air flow rate of the engine, and the vehicle speed.
5. The method for estimating the coolant temperature according to claim 2, wherein: Determining the temperature change base value of the current coolant temperature according to the estimation mode includes: When the estimation mode is the third mode, a temperature change base value of the current coolant temperature is determined according to the ambient temperature of the environment in which the vehicle is located and the intake air flow rate of the engine.
6. The method for estimating the coolant temperature according to claim 2, wherein: Determining the temperature change base value of the current coolant temperature according to the estimation mode includes: When the estimation mode is the fourth mode, a temperature change base value of the current coolant temperature is determined according to the ambient temperature of the environment in which the vehicle is located and the shutdown duration of the engine.
7. The method for estimating the coolant temperature according to any one of claims 1 to 6, characterized in that: The determining of the temperature change correction value of the current coolant temperature according to the temperature change base value, the temperature adjustment coefficient and the cooling compensation value includes: The product of the temperature change base value and the temperature adjustment coefficient is added to the cooling compensation value to obtain the temperature change correction value of the current coolant temperature.
8. The method for estimating the coolant temperature according to any one of claims 1 to 6, characterized in that: The cooling circuit further includes a fan and a thermostat. Before determining the temperature change correction value of the current coolant temperature based on the temperature change base value, the temperature adjustment coefficient, and the cooling compensation value, the estimating method further includes: determining the temperature adjustment coefficient according to the ambient temperature of the environment in which the vehicle is located and the temperature change base value; The cooling compensation value is determined according to the ambient temperature, the rotation speed percentage of the fan, and the opening percentage of the thermostat.
9. The method for estimating the coolant temperature according to any one of claims 1 to 6, characterized in that: In the case where the target estimated value of the current coolant temperature needs to be reset, before determining the sum of the temperature change correction value and the previous target estimated value of the coolant temperature as the target estimated value of the current coolant temperature, the estimation method further includes: If the engine does not run for more than a first preset time after the vehicle is powered off, or if the vehicle is running in pure electric mode and the engine does not run for more than a second preset time, it is determined that the target estimated value of the current coolant temperature needs to be reset.
10. A device for estimating coolant temperature, comprising a processor and a memory, characterized in that: The memory stores computer program instructions that can be executed by the processor, and when the processor executes the computer program instructions, the steps of the method according to any one of claims 1 to 9 are implemented.