Vehicle fan rotating speed open-loop control method, system and equipment and storage medium

Abstract

The invention relates to the technical field of automobiles, and particularly provides an open-loop control method, system and device for the rotating speed of a vehicle fan and a storage medium. Calculating the temperature change rate and the first-order derivative of the key part in the preset time window, and the environment temperature change quantity; carrying out comparative judgment with hysteresis on the three variable quantities and a preset threshold value, outputting trend symbols, and combining the trend symbols into a temperature trend combination representing a temperature dynamic trend; based on the combined look-up table, determining a heat dissipation power gear and generating a heat dissipation power request; according to the heat dissipation power request, the vehicle speed and the environment temperature, a fan rotating speed request is inversely solved in combination with a preset radiator capacity function; according to the method, advanced perception and dynamic feedforward control of the heat dissipation demand are realized by introducing the second-order temperature trend criterion and hysteresis quantitative judgment.

Description

Technical Field

[0001] This invention belongs to the field of automotive technology, specifically relating to a method, system, device, and storage medium for open-loop control of vehicle fan speed. Background Technology

[0002] With the rapid development of pure electric and hybrid vehicles, the integration of their powertrain and electrical systems is increasing. Key components such as the electric drive assembly and power electronics modules continuously generate a large amount of heat during operation, and inadequate heat dissipation can easily lead to overheating and damage. Currently, vehicle fan control mainly employs two methods: open-loop and closed-loop. Open-loop control is based on a fixed temperature threshold, which is simple but lacks anti-interference capabilities and predictability. Closed-loop control, while offering more precise adjustment, typically relies on high-precision sensors, resulting in higher costs, and its complex algorithms face real-time challenges. Existing solutions either rely on long-term time-series data that is difficult to predict accurately or fail to fully consider the impact of dynamic factors such as vehicle speed on heat dissipation in the in-vehicle environment, limiting both control effectiveness and applicability. Therefore, there is an urgent need for a vehicle fan control method that can achieve proactive temperature regulation without relying on complex sensors and high computing power requirements. Summary of the Invention

[0003] In view of the above-mentioned shortcomings of the prior art, the present invention provides a method, system, device and storage medium for open-loop control of vehicle fan speed to solve the above-mentioned technical problems.

[0004] In a first aspect, the present invention provides an open-loop control method for vehicle fan speed, comprising: Collect data on the temperature of key vehicle components, ambient temperature, and vehicle speed; Based on the collected data, the temperature change rate and the first derivative of the temperature change rate of key components within a preset time window, as well as the change in ambient temperature, are calculated. The temperature change rate, the first derivative of the temperature change rate, the change in ambient temperature, and a preset threshold are compared and judged with hysteresis, and the corresponding trend symbols are output. Multiple trend symbols are combined into a temperature trend combination that represents the current dynamic temperature trend. The heat dissipation power level is determined based on the temperature trend combination and a predefined mapping table, and a heat dissipation power request is generated based on the heat dissipation power level. Based on the requested heat dissipation power, vehicle speed, and ambient temperature, and combined with a preset radiator capability function, the requested fan speed is calculated.

[0005] In an optional implementation, the method further includes: The fan speed request is maintained within the set time window. When the temperature of a critical component exceeds the high temperature threshold or the rate of temperature rise exceeds the limit, protective speed regulation measures are triggered. The protective speed control measures include: controlling the fan speed to a preset maximum speed.

[0006] In one optional implementation, the temperature of key vehicle components, ambient temperature, and vehicle speed are collected, including: Temperature sensors are placed on key components to collect the temperature of the key components, including the vehicle electric drive assembly, power electronic module and battery circuit radiator. The ambient temperature is collected by a vehicle ambient temperature sensor; Vehicle speed signal is obtained via the vehicle's CAN bus.

[0007] In one optional implementation, based on the collected data, the temperature change rate and the first derivative of the temperature change rate of key components within a preset time window, as well as the change in ambient temperature, are calculated, including: Within a preset fixed time window, the temperature signals of the key components are filtered and their average value is calculated. Based on the average value, the temperature change rate is calculated by discretizing the differential equation of the preset thermal system RC network model; The discretization method is applied again to the temperature change rate to calculate its rate of change, which is used as the first derivative of the temperature change rate. Calculate the difference between the current time window's average ambient temperature and the previous time window's average ambient temperature, and use this difference as the change in ambient temperature. The thermal system RC network model is a mathematical model that abstracts the vehicle thermal management system as an equivalent circuit. In this model, thermal capacity is simulated as capacitance to characterize the ability of a component or coolant to store heat; thermal resistance is simulated as resistance to characterize the resistance encountered when heat is transferred between the component and the coolant, and between the coolant and the ambient air. The model constructs a complete heat transfer path from the heat source of the key component to the ambient air by connecting these thermal resistances and thermal capacities.

[0008] In an optional implementation, the temperature change rate, the first derivative of the temperature change rate, the change in ambient temperature, and a preset threshold are compared and judged with hysteresis, and corresponding trend symbols are output. Multiple trend symbols are then combined into a temperature trend combination representing the current dynamic temperature trend, including: The temperature change rate, the first derivative of the temperature change rate, and the change in ambient temperature are respectively input into the hysteresis quantization discrimination function; The hysteresis quantization discriminant function includes:

[0009] in, The trend sign for the i-th parameter in the k-th time window is represented. ; Indicates the threshold. Indicates the hysteresis band; This represents the value of parameter i for the k-th time window; The trend symbol group obtained in the current time window Mapped to a predefined quadrant q, where each quadrant uniquely corresponds to a set of ternary trend symbols. The defined combination of physical states, which is the temperature trend combination, fully describes the overall situation of the system being heated or cooled, the rate of heating being accelerated or slowed down, and the external environment being favorable or unfavorable to heat dissipation.

[0010] In an optional implementation, the heat dissipation power level is determined based on the temperature trend combination and a predefined mapping table, and a heat dissipation power request is generated based on the heat dissipation power level, including: Based on the temperature trend combination, a basic heat dissipation power level is obtained by querying a predefined first mapping table. Obtain a real-time operating condition feature vector that includes at least one of the following factors: battery state of charge (SOC), ambient temperature, signal variance, and vehicle aging level. The real-time operating condition feature vector is standardized and then weighted with a preset weight vector to generate a comprehensive correction factor. The comprehensive correction factor is constrained within a preset range to obtain the final correction factor; and the equivalent threshold after adaptive correction is calculated based on the correction factor and the initial threshold. The temperature change rate, the first derivative of the temperature change rate, and the change in ambient temperature are compared with the corresponding equivalent thresholds to generate the level quantification correction parameters, wherein each correction parameter takes the value of 1, 0, or -1. The basic heat dissipation power level is summed with the level quantization correction parameter to obtain a preliminary corrected level value; the preliminary corrected level value is input into a limiting function for processing, and the limiting function constrains its output value between a preset minimum level and a maximum level. The output of the limiting function is the final heat dissipation power level. Based on the final heat dissipation power level, the predefined second mapping table is queried to obtain the heat dissipation power request.

[0011] In an optional implementation, based on the requested cooling power, vehicle speed, and ambient temperature, and in conjunction with a preset radiator capability function, the requested fan speed is derived, including: The heat dissipation power request Current vehicle speed and current ambient temperature Substitute the heatsink capability function ,in The overall heat transfer coefficient is... , , For calibration coefficients, This refers to the hot-side temperature of the radiator. This refers to the fan speed; Based on the heat sink capability function, the solution that satisfies the heat dissipation power request is obtained through inverse calculation. Required theoretical fan speed :

[0012] in, This represents the requested heat dissipation power value for the current time window k. The theoretical fan speed Mapped to a predefined set of executable discrete speeds The speed must be no less than its minimum speed value, which is the final fan speed request; When the protective speed control measure is triggered, the requested fan speed is directly set to the maximum value in the discrete speed set. .

[0013] In a second aspect, the present invention provides an open-loop control system for vehicle fan speed, comprising: The data acquisition module is used to collect data on the temperature of key vehicle components, ambient temperature, and vehicle speed. The change calculation module is used to calculate the temperature change rate and the first derivative of the temperature change rate of key components within a preset time window, as well as the change in ambient temperature, based on the collected data. The trend mapping module is used to compare and distinguish the temperature change rate, the first derivative of the temperature change rate, the change in ambient temperature with a preset threshold with hysteresis, output the corresponding trend symbol, and combine multiple trend symbols into a temperature trend combination that represents the current temperature dynamic trend. The power level determination module is used to determine the heat dissipation power level based on the temperature trend combination and a predefined mapping table, and to generate a heat dissipation power request based on the heat dissipation power level. The speed inverse solution module is used to inversely solve the fan speed request based on the heat dissipation power request, vehicle speed, and ambient temperature, combined with a preset radiator capability function.

[0014] Thirdly, a device is provided, comprising: The memory is used to store the open-loop control program for the vehicle's fan speed. A processor is configured to implement the steps of the vehicle fan speed open-loop control method as provided in the first aspect when executing the vehicle fan speed open-loop control program.

[0015] Fourthly, a computer-readable storage medium is provided, on which a vehicle fan speed open-loop control program is stored, wherein when the vehicle fan speed open-loop control program is executed by a processor, the steps of the vehicle fan speed open-loop control method as provided in the first aspect are implemented.

[0016] The beneficial effects of this invention are as follows: the vehicle fan speed open-loop control method, system, device, and storage medium provided by this invention, by introducing second-order temperature trend criteria and hysteresis quantization discrimination, achieves advanced perception and dynamic feedforward control of heat dissipation demand, effectively overcoming the shortcomings of traditional open-loop control (lack of predictability) and closed-loop control (high cost and poor real-time performance). Its beneficial effects are: by coordinating the judgment of temperature change rate and its acceleration, the temperature rise trend can be identified in advance, enabling advanced adjustment of fan speed; by utilizing hysteresis comparison and a fixed time window strategy, control command jitter caused by sensor noise is significantly suppressed; by combining parameters such as vehicle speed and ambient temperature to inversely solve the speed through a physical model, the control is made more closely aligned with actual heat dissipation characteristics, improving energy efficiency; at the same time, a high-temperature protection threshold is set to ensure that the system immediately triggers maximum heat dissipation power when the temperature rises too quickly, ensuring the operational safety and reliability of key components. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic flowchart of a method according to an embodiment of the present invention.

[0019] Figure 2 This is a schematic block diagram of a system according to an embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram of the structure of a device provided in an embodiment of the present invention. Detailed Implementation

[0021] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0023] The vehicle fan speed open-loop control method provided in this embodiment of the invention is executed by a computer device, and correspondingly, the vehicle fan speed open-loop control system runs in the computer device.

[0024] Figure 1 This is a schematic flowchart illustrating a method according to an embodiment of the present invention. Wherein, Figure 1 The executing entity can be an open-loop control system for vehicle fan speed. Depending on different requirements, the order of steps in this flowchart can be changed, and some steps can be omitted.

[0025] like Figure 1 As shown, the method includes: S1. Collect data on the temperature of key vehicle components, ambient temperature, and vehicle speed; S2. Based on the collected data, calculate the temperature change rate and the first derivative of the temperature change rate of key components within a preset time window, as well as the change in ambient temperature; S3. The temperature change rate, the first derivative of the temperature change rate, the change in ambient temperature, and a preset threshold are compared and judged with hysteresis, the corresponding trend symbols are output, and multiple trend symbols are combined into a temperature trend combination representing the current temperature dynamic trend. S4. Determine the heat dissipation power level based on the temperature trend combination and the predefined mapping table, and generate a heat dissipation power request based on the heat dissipation power level; S5. Based on the requested heat dissipation power, vehicle speed, and ambient temperature, and combined with the preset radiator capability function, the requested fan speed is calculated.

[0026] In one embodiment of the present invention, based on step S1, the following will provide a possible embodiment and describe its specific implementation in a non-limiting manner.

[0027] Temperature data for critical vehicle components is collected using temperature sensors installed on various key heat-generating parts. Specifically, temperature sensors of the negative temperature coefficient (NTC) thermistor or thermocouple type are installed at the inlet or outlet of the vehicle's electric drive assembly (such as the drive motor stator or housing), power electronics modules (such as the motor controller, IGBT heat sink of the multi-function controller), and battery circuit radiator. These sensors directly measure the surface temperature of the components or the coolant temperature, and convert the analog signals into digital signals via an analog-to-digital converter (ADC) before sending them to the vehicle control unit (VCU) or a dedicated thermal management controller.

[0028] Ambient temperature data is collected by an ambient temperature sensor installed near the front grille of the vehicle or in a well-ventilated location in the engine compartment. This sensor must be protected from direct exposure to exhaust heat or radiant heat from the exhaust system to ensure the accuracy of the measured ambient temperature data.

[0029] Vehicle speed signals are acquired indirectly from the vehicle controller or the wheel speed sensors of the anti-lock braking system (ABS) via the vehicle's built-in CAN bus network, without relying on additional hardware sensors. The controller obtains real-time, continuous vehicle speed information by parsing the vehicle speed field in the CAN bus message.

[0030] All collected temperature and vehicle speed data are read at a fixed sampling period (e.g., 100 milliseconds) and stored in the controller's buffer, providing a data foundation for subsequent data preprocessing and trend analysis calculations within a preset time window.

[0031] In one embodiment of the present invention, based on step S2, the following will provide a possible embodiment and describe its specific implementation in a non-limiting manner.

[0032] First, a fixed calculation time window W is set, for example, 10 seconds in length. Within this time window, the raw temperature signals of the continuously acquired key components are filtered in real time. In one specific embodiment, a first-order low-pass digital filter or a moving average filter is used to effectively suppress high-frequency components of measurement noise. After filtering, the arithmetic mean of all filtered temperature data within the time window is calculated and used as the baseline temperature value for trend analysis in this period.

[0033] Subsequently, based on this average value, the rate of temperature change is calculated by discretizing the differential equations of the pre-defined thermal system RC network model. Specifically, the forward Euler method is used to discretize and approximate the differential terms in the model, thereby solving for the rate of temperature change at the current moment. .

[0034] The differential equations of the RC network model of the thermal system include:

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041] in, This indicates that the all-in-one controller is causing a rise in coolant temperature. This indicates that the motor controller caused the coolant temperature rise. This indicates the temperature rise caused by the motor and the coolant. Indicates the coolant mass flow rate. Indicates the specific heat capacity of the coolant. Indicates the coolant temperature at the radiator outlet. This indicates the outlet coolant temperature of the all-in-one controller. This indicates the outlet coolant temperature of the motor controller. Indicates the coolant temperature at the motor outlet. Indicates the temperature of the all-in-one controller. Indicates the temperature of the motor controller. Indicates motor temperature. This indicates the heating power of the all-in-one controller. Indicates the heating power of the motor controller. Indicates the motor's heating power. Indicates the heat capacity of the all-in-one controller. Indicates the thermal capacity of the motor controller. Indicates the heat capacity of the motor. This indicates the equivalent heat capacity of the radiator. This indicates the equivalent thermal resistance of the all-in-one controller. This represents the equivalent thermal resistance of the motor controller. This indicates the equivalent thermal resistance between the motor and the coolant. Indicates the equivalent thermal resistance of the heat sink. Indicates the equivalent heat transfer capacity. Indicates ambient temperature.

[0042] Next, the temperature change rate calculated above will be... It is treated as a new time series, and the same discretization method (such as Euler's method) is applied to it again to calculate the change between adjacent periods, which is then used as the first derivative of the rate of temperature change. This refers to the "acceleration of temperature change".

[0043] Meanwhile, for ambient temperature, the current time window is calculated separately. and the previous time window The average ambient temperature inside. The difference between these two averages, i.e. env[k] represents the change in ambient temperature during this calculation period.

[0044] All calculated characteristic quantities It will be passed to the subsequent trend analysis module for use.

[0045] In one embodiment of the present invention, based on step S3, the following will provide a possible embodiment and describe its specific implementation in a non-limiting manner.

[0046] The temperature change rate, the first derivative of the temperature change rate, and the change in ambient temperature are respectively input into the hysteresis quantization discrimination function; The hysteresis quantization discriminant function includes:

[0047] in, The trend sign for the i-th parameter in the k-th time window is represented. ; Indicates the threshold. Indicates the hysteresis band; This represents the value of parameter i for the k-th time window; The current time window Substituting the hysteresis quantization discriminant function, we obtain the trend sign group. .

[0048] If it exists Then the quadrant determination retains the determination result from the previous time step. Otherwise, we have: Trend symbol group coming soon. This is mapped to a predefined quadrant q, where each quadrant uniquely corresponds to a combination of temperature trends consisting of heating / cooling, acceleration / deceleration, and favorable / unfavorable external conditions. For example, correspond This indicates cooling, slowing down, and favorable external conditions. Quadrant The corresponding quadrant (-1, -1, 1) represents a trend combination of "cooling down, slowing down, and unfavorable external conditions," and so on, for a total of eight quadrants.

[0049] Setting quadrants is the core and innovation of this patent's control strategy. Its fundamental purpose is to transform the continuous and complex dynamic behavior of the thermal system into finite, discrete, and operable "state tags," thereby enabling intelligent and forward-looking judgment of heat dissipation needs.

[0050] Specifically, this setup is based on the following three core considerations: Construct a complete state awareness system: These eight quadrants constitute a complete "state-aware dictionary." It comprehensively depicts the thermal state of the system through three of the most representative dimensions: First-order trend (warming / cooling): Answers "In which direction is the current temperature changing?"

[0051] Second-order trend (acceleration / deceleration): Answering the question "Is the current trend of change strengthening or weakening?" is key to achieving "predictability".

[0052] External environment (favorable / unfavorable): Answer "Is the environment helping to dissipate heat or exacerbating the temperature rise?"

[0053] By combining the "yes" or "no" responses of these three dimensions (quantified as +1 or -1), 2 was derived. 3 =8 indivisible basic states, covering all possible thermal dynamic scenarios.

[0054] To achieve a mapping from "phenomenon" to "intention": Each quadrant is no longer a simple combination of mathematical symbols, but is given a clear physical meaning and a controlling "intention".

[0055] For example, Q1(-1,-1,-1): cooling, deceleration, favorable external conditions. This clearly indicates that the system is in a state of "good heat dissipation and still improving". The controller's "intention" is naturally to maintain or even reduce the heat dissipation power.

[0056] Conversely, for example, Q5(1,1,-1): heating up, accelerating, favorable external conditions. This is a strong warning sign: even with favorable conditions, the temperature is still rising rapidly, indicating a huge internal heat generation capacity. The controller's "intention" must be to "strongly demand increased heat dissipation capacity".

[0057] Provides precise indexes for table lookup control: This 8-quadrant system provides a perfect and efficient index for subsequent "table lookup to determine the basic power level". The controller does not need to perform complex online calculations; it only needs to retrieve the most suitable basic control command (heat dissipation power level) corresponding to the current quadrant number q from the pre-calibrated table. This ensures both the speed of control and solidifies the engineer's experience and optimization results in the table.

[0058] In summary, this quadrant setting method essentially simplifies advanced control strategies based on physical models into a highly efficient lookup operation based on a state machine. It enables the control system to not only see the "present" but also anticipate the "momentum," thus achieving a leap from passive response to proactive intervention. This is the fundamental reason why it outperforms traditional fixed threshold methods.

[0059] In one embodiment of the present invention, based on step S4, the following will provide a possible embodiment and describe its specific implementation in a non-limiting manner.

[0060] First, based on the quadrant numbers output during the trend discrimination phase. Query the first mapping table (basic level table) pre-stored in the controller to obtain the corresponding basic heat dissipation power level. , This table defines the basic heat dissipation intensity required for different combinations of temperature trends.

[0061] The "first mapping table" (basic gear table) is not set arbitrarily, but is predetermined and fixed in the controller based on a combination of engineering experience, system simulation and bench testing.

[0062] The specific construction process is as follows: Theoretical Analysis and Model Simulation: Based on the aforementioned thermal system RC network model, through extensive simulations, the theoretical power range required by the heat dissipation system to maintain the temperature of key components within a safe and efficient range is analyzed under eight thermal dynamic trends represented by different quadrants.

[0063] Engineer experience and design goals: Based on the theoretical scope derived from simulation, engineers will determine the specific design goals for each vehicle model. These goals include: Safety: Ensure that under any circumstances, the power demand is sufficient to prevent overheating.

[0064] Energy consumption optimization: Under the premise of ensuring safety, select the lowest power setting as much as possible to save energy and extend the battery life.

[0065] Noise control: Avoid unnecessary frequent fluctuations in fan speed (related to power) or high-speed operation to improve driving comfort.

[0066] System responsiveness: Ensures that power requests can keep up with the dynamic process of temperature changes.

[0067] Bench Testing and Final Calibration: The initially established mapping table was tested on a thermal management bench. The bench can simulate various extreme operating conditions of the vehicle (such as climbing, rapid acceleration, high-temperature environments, etc.). Through repeated testing and adjustments (i.e., the "calibration" process), it was observed whether the assigned base power level could always control the component temperature within the ideal range when triggered in different quadrants, while also considering low energy consumption and low noise. Finally, the optimal quadrant q -> base power level mapping relationship was determined in all test scenarios and burned into the controller as the first mapping table.

[0068] In summary, the first mapping table is the "crystallization of wisdom" and "experience base" of the control strategy of this invention. It transforms the complex physical model and the design experience of engineers into a concise and efficient lookup table, and is a key component in realizing the beneficial effects of this invention.

[0069] At the same time, the controller obtains the battery state of charge in real time. Ambient temperature Variance of each signal within the time window The operating condition feature vector H is composed of the parameter age, which characterizes the degree of vehicle aging. After standardizing the feature values ​​of each dimension, they are weighted and summed with the preset weight vector ω to obtain the comprehensive correction factor μ. Constrain the factor within a preset range. Within this process, the final correction factor is obtained. Using this correction factor, according to the formula... The equivalent threshold after adaptive correction is calculated. , , .

[0070] Then, the currently calculated , , Each parameter is compared with its corresponding equivalent threshold to generate a level quantization correction parameter.

[0071]

[0072]

[0073] The rules for each parameter are as follows: take 1 when the input value is greater than or equal to its equivalent threshold; take -1 when it is less than or equal to the opposite of the equivalent threshold; and take 0 when it is in between.

[0074] Next, shift to the base gear. Adding this value to the three levels of quantization correction parameters yields the initially corrected gear value. This value is then input into the clipping function clip(•,1,L). max This constrains it to the preset minimum gear 1 and maximum gear L. max Between these values, the output is the final heat dissipation power level: .

[0075] Finally, based on the final gear Query the predefined second mapping table (power request table) to obtain the specific heat dissipation power request value. This power request will be passed to the fan speed calculation module.

[0076] The determination of the "second mapping table (power request table)" is an engineering calibration process that matches discrete control commands (gear positions) with continuous physical system capabilities. It originates from the testing, modeling, and optimization of the physical characteristics of the vehicle's cooling system, and its construction is mainly based on the following steps: Performance characterization of the cooling system (bench testing): The core task is to obtain the heat dissipation power characteristic curve of the entire cooling system (radiator + fan). On an environmental test bench, by controlling different ambient temperatures, vehicle speeds (simulating wind speed), and fan speeds, the maximum heat (i.e., heat dissipation power) that the radiator can remove under different operating conditions is accurately measured. These test data are used to calibrate and verify the radiator capability function mentioned in the claims. The coefficients K,c v ,c n c0 ensures that the model accurately reflects the physical capabilities of the actual system.

[0077] Power Range Division and Gear Allocation: Based on the system's maximum and minimum heat dissipation capabilities obtained in the first step, and combined with the vehicle's peak heat dissipation requirements under the most severe operating conditions, the required heat dissipation power range for the entire control process is determined. This power range is then rationally divided into L... max A series of consecutive intervals. Each interval corresponds to a final heat dissipation power level for the gear. final The partitioning strategy needs to consider: Control precision: Set more frequent gears in critical power ranges (such as the commonly used low and medium load range) to achieve fine control.

[0078] Actuator characteristics: Consider the efficiency and noise characteristics of the fan at different speed ranges, and avoid setting the speed range in the inefficient or resonant speed range of the fan.

[0079] Power value determination and optimization: for each gear final Assign a specific power request value Q req This value is typically set to the upper limit of the power range corresponding to that gear setting, or an optimized setting, to ensure sufficient headroom for heat dissipation. The final mapping relationship is Table[gear]. final ] = Q req It needs to be verified and fine-tuned through full vehicle road tests to ensure that the power request issued by the table can meet the heat dissipation requirements and achieve the best balance between system energy consumption and noise in all real driving scenarios.

[0080] In one embodiment of the present invention, based on step S5, a possible embodiment will be given below, and its specific implementation will be described in a non-limiting manner.

[0081] The heat dissipation power request Current vehicle speed and current ambient temperature Substitute the heatsink capability function ,in The overall heat transfer coefficient, , , For calibration coefficients, This refers to the hot-side temperature of the radiator. This refers to the fan speed; Based on the heat sink capability function, the solution that satisfies the heat dissipation power request is obtained through inverse calculation. Required theoretical fan speed :

[0082] in, This represents the requested cooling power value for the current time window k. The theoretical fan speed Mapped to a predefined set of executable discrete speeds The value of the fan speed request is not less than its minimum speed value, and this speed value is the final fan speed request. That is, a set of discrete fan request points is defined. It meets the following conditions.

[0083] in, This indicates the logic for rounding up the rotational speed.

[0084] Specifically, the requested fan speed is maintained within a set time window. When the temperature of a critical component exceeds a high-temperature threshold or the rate of temperature rise exceeds a limit, protective speed regulation measures are triggered. When the protective speed regulation measures are triggered, the requested fan speed is directly set to the maximum value in the discrete speed set. .

[0085] If the system contains M heat dissipation branches, each branch will provide a different heat dissipation power request after determining the gear position. Each branch is equipped with one or more fans, and the fan speed of the i-th branch is denoted as the decision variable. The overall fan speed vector can be expressed as: .

[0086] Following the steps outlined above, calibrate the model parameters for different branches and introduce a heat dissipation relaxation factor. ,have .

[0087] Construct a multi-objective weighted cost function that includes temperature safety, energy consumption, noise, etc., with the specific expression as follows:

[0088] in, This indicates the penalty weight for exceeding the temperature limit. Indicates energy consumption. This represents the noise smoothness weight. Clearly, this optimization problem is a convex quadratic programming problem, which can be solved using a general solver.

[0089] For the requested rotational speeds output by the optimizer, the solution values ​​are mapped to the set of executable rotational speeds using the discretization rules shown in the steps above.

[0090] In some embodiments, the vehicle fan speed open-loop control system may include multiple functional modules composed of computer program segments. The computer programs for each program segment in the vehicle fan speed open-loop control system may be stored in the memory of a computer device and executed by at least one processor to perform (see details). Figure 1 (Description) The function of open-loop control of vehicle fan speed.

[0091] In this embodiment, the vehicle fan speed open-loop control system can be divided into multiple functional modules according to its functions, such as... Figure 2 As shown. The module referred to in this invention is a series of computer program segments that can be executed by at least one processor and perform a fixed function, and is stored in memory. In this embodiment, the functions of each module will be described in detail in subsequent embodiments.

[0092] The data acquisition module is used to collect data on the temperature of key vehicle components, ambient temperature, and vehicle speed. The change calculation module is used to calculate the temperature change rate and the first derivative of the temperature change rate of key components within a preset time window, as well as the change in ambient temperature, based on the collected data. The trend mapping module is used to compare and distinguish the temperature change rate, the first derivative of the temperature change rate, the change in ambient temperature with a preset threshold with hysteresis, output the corresponding trend symbol, and combine multiple trend symbols into a temperature trend combination that represents the current temperature dynamic trend. The power level determination module is used to determine the heat dissipation power level based on the temperature trend combination and a predefined mapping table, and to generate a heat dissipation power request based on the heat dissipation power level. The speed inverse solution module is used to inversely solve the fan speed request based on the heat dissipation power request, vehicle speed, and ambient temperature, combined with a preset radiator capability function.

[0093] Figure 3The open-loop control method for vehicle fan speed provided in this application embodiment can be applied to devices. Those skilled in the art will understand that the device structure involved in the embodiments of this invention does not constitute a limitation on the device. A device may include more or fewer components than illustrated, or combine certain components, or have different component arrangements. In the embodiments of this invention, the device includes, but is not limited to, laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The device may also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the embodiments of this application described and / or claimed herein.

[0094] The device 300 may include a processor 310, a memory 320, and a communication unit 330. These components communicate via one or more buses. Those skilled in the art will understand that the server structure shown in the figure does not constitute a limitation of the present invention. It may be a bus topology or a star topology, and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0095] The memory 320 can be used to store execution instructions of the processor 310. The memory 320 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. When the execution instructions in the memory 320 are executed by the processor 310, the device 300 is able to perform some or all of the steps in the above method embodiments.

[0096] The processor 310 serves as the control center of the storage device, connecting various parts of the electronic device via various interfaces and lines. It executes software programs and / or modules stored in the memory 320, and calls data stored in the memory to perform various functions of the electronic device and / or process data. The processor can be composed of integrated circuits (ICs), such as a single packaged IC or multiple packaged ICs with the same or different functions connected together. For example, the processor 310 may consist only of a central processing unit (CPU). In this embodiment of the invention, the CPU may have a single processing core or include multiple processing cores.

[0097] The communication unit 330 is used to establish a communication channel, enabling the storage device to communicate with other devices. It can receive user data sent by other devices or send user data to other devices.

[0098] The present invention also provides a computer storage medium, wherein the computer storage medium may store a program, which, when executed, may include some or all of the steps provided in the embodiments of the present invention. The storage medium may be a magnetic disk, an optical disk, read-only memory (ROM), or random access memory (RAM), etc.

[0099] Those skilled in the art will clearly understand that the techniques in the embodiments of the present invention can be implemented using software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solutions in the embodiments of the present invention, or the parts that contribute to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, or any other medium capable of storing program code. It includes several instructions to cause a computer device (which may be a personal computer, a server, or a second device, network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention.

[0100] The same or similar parts between the various embodiments in this specification can be referred to mutually. In particular, the device embodiments are basically similar to the method embodiments, so the description is relatively simple, and the relevant parts can be referred to the description in the method embodiments.

[0101] In the embodiments provided by this invention, it should be understood that the disclosed systems and methods can be implemented in other ways. For example, the system embodiments described above are merely illustrative. For instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between systems or modules may be electrical, mechanical, or other forms.

[0102] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical modules; that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0103] In addition, the functional modules in the various embodiments of the present invention can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0104] Although the present invention has been described in detail with reference to the accompanying drawings and preferred embodiments, the present invention is not limited thereto. Various equivalent modifications or substitutions can be made to the embodiments of the present invention by those skilled in the art without departing from the spirit and essence of the invention, and such modifications or substitutions should all be within the scope of the present invention. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should also be covered within the protection scope of the present invention.

Claims

1. A method for open-loop control of vehicle fan speed, characterized in that, include: Collect data on the temperature of key vehicle components, ambient temperature, and vehicle speed; Based on the collected data, the temperature change rate and the first derivative of the temperature change rate of key components within a preset time window, as well as the change in ambient temperature, are calculated. The temperature change rate, the first derivative of the temperature change rate, the change in ambient temperature, and a preset threshold are compared and judged with hysteresis, and the corresponding trend symbols are output. Multiple trend symbols are combined into a temperature trend combination that represents the current dynamic temperature trend. The heat dissipation power level is determined based on the temperature trend combination and a predefined mapping table, and a heat dissipation power request is generated based on the heat dissipation power level. Based on the requested heat dissipation power, vehicle speed, and ambient temperature, and combined with a preset radiator capability function, the requested fan speed is calculated.

2. The method according to claim 1, characterized in that, The method further includes: The fan speed request is maintained within the set time window. When the temperature of a critical component exceeds the high temperature threshold or the rate of temperature rise exceeds the limit, protective speed regulation measures are triggered. The protective speed control measures include: controlling the fan speed to a preset maximum speed.

3. The method according to claim 1, characterized in that, Collect data on the temperature of key vehicle components, ambient temperature, and vehicle speed, including: Temperature sensors are placed on key components to collect the temperature of the key components, including the vehicle electric drive assembly, power electronic module and battery circuit radiator. The ambient temperature is collected by a vehicle ambient temperature sensor; Vehicle speed signal is obtained via the vehicle's CAN bus.

4. The method according to claim 1, characterized in that, Based on the collected data, the temperature change rate and first derivative of the temperature change rate of key components within a preset time window are calculated, as well as the change in ambient temperature, including: Within a preset fixed time window, the temperature signals of the key components are filtered and their average value is calculated. Based on the average value, the temperature change rate is calculated by discretizing the differential equation of the preset thermal system RC network model; The discretization method is applied again to the temperature change rate to calculate its rate of change, which is used as the first derivative of the temperature change rate. Calculate the difference between the current time window's average ambient temperature and the previous time window's average ambient temperature, and use this difference as the change in ambient temperature. The thermal system RC network model is a mathematical model that abstracts the vehicle thermal management system as an equivalent circuit. In this model, thermal capacity is simulated as capacitance to characterize the ability of a component or coolant to store heat; thermal resistance is simulated as resistance to characterize the resistance encountered when heat is transferred between the component and the coolant, and between the coolant and the ambient air. The model constructs a complete heat transfer path from the heat source of the key component to the ambient air by connecting these thermal resistances and thermal capacities.

5. The method according to claim 1, characterized in that, The temperature change rate, the first derivative of the temperature change rate, the change in ambient temperature, and a preset threshold are compared and judged with hysteresis. Corresponding trend symbols are output, and multiple trend symbols are combined into a temperature trend combination representing the current dynamic temperature trend, including: The temperature change rate, the first derivative of the temperature change rate, and the change in ambient temperature are respectively input into the hysteresis quantization discrimination function; The hysteresis quantization discriminant function includes: in, The trend sign for the i-th parameter in the k-th time window is represented. ; Indicates the threshold. Indicates the hysteresis band; This represents the value of parameter i for the k-th time window; The trend symbol group obtained in the current time window Mapped to a predefined quadrant q, where each quadrant uniquely corresponds to a set of ternary trend symbols. The defined combination of physical states, which is the temperature trend combination, fully describes the overall situation of the system being heated or cooled, the rate of heating being accelerated or slowed down, and the external environment being favorable or unfavorable to heat dissipation.

6. The method according to claim 1, characterized in that, Based on the temperature trend combination and a predefined mapping table, the heat dissipation power level is determined, and a heat dissipation power request is generated based on the heat dissipation power level, including: Based on the temperature trend combination, a basic heat dissipation power level is obtained by querying a predefined first mapping table. Obtain a real-time operating condition feature vector that includes at least one of the following factors: battery state of charge (SOC), ambient temperature, signal variance, and vehicle aging level. The real-time operating condition feature vector is standardized and then weighted with a preset weight vector to generate a comprehensive correction factor. The comprehensive correction factor is constrained within a preset range to obtain the final correction factor; and the equivalent threshold after adaptive correction is calculated based on the correction factor and the initial threshold. The temperature change rate, the first derivative of the temperature change rate, and the change in ambient temperature are compared with the corresponding equivalent thresholds to generate the level quantification correction parameters, wherein each correction parameter takes the value of 1, 0, or -1. The basic heat dissipation power level is summed with the level quantization correction parameter to obtain a preliminary corrected level value; the preliminary corrected level value is input into a limiting function for processing, and the limiting function constrains its output value between a preset minimum level and a maximum level. The output of the limiting function is the final heat dissipation power level. Based on the final heat dissipation power level, the predefined second mapping table is queried to obtain the heat dissipation power request.

7. The method according to claim 2, characterized in that, Based on the requested cooling power, vehicle speed, and ambient temperature, and using a preset radiator capability function, the requested fan speed is calculated, including: The heat dissipation power request Current vehicle speed and current ambient temperature Substitute the heatsink capability function ,in The overall heat transfer coefficient, , , For calibration coefficients, This refers to the hot-side temperature of the radiator. This refers to the fan speed; Based on the heat sink capability function, the solution that satisfies the heat dissipation power request is obtained through inverse calculation. Required theoretical fan speed : in, This represents the requested heat dissipation power value for the current time window k. The theoretical fan speed Mapped to a predefined set of executable discrete speeds The speed must be no less than its minimum speed value, which is the final fan speed request; When the protective speed control measure is triggered, the requested fan speed is directly set to the maximum value in the discrete speed set. .

8. An open-loop control system for vehicle fan speed, characterized in that, include: The data acquisition module is used to collect data on the temperature of key vehicle components, ambient temperature, and vehicle speed. The change calculation module is used to calculate the temperature change rate and the first derivative of the temperature change rate of key components within a preset time window, as well as the change in ambient temperature, based on the collected data. The trend mapping module is used to compare and distinguish the temperature change rate, the first derivative of the temperature change rate, the change in ambient temperature with a preset threshold with hysteresis, output the corresponding trend symbol, and combine multiple trend symbols into a temperature trend combination that represents the current temperature dynamic trend. The power level determination module is used to determine the heat dissipation power level based on the temperature trend combination and a predefined mapping table, and to generate a heat dissipation power request based on the heat dissipation power level. The speed inverse solution module is used to inversely solve the fan speed request based on the heat dissipation power request, vehicle speed, and ambient temperature, combined with a preset radiator capability function.

9. A vehicle fan speed open-loop control device, characterized in that, include: The memory is used to store the open-loop control program for the vehicle's fan speed. A processor is configured to implement the steps of the vehicle fan speed open-loop control method as described in any one of claims 1-7 when executing the vehicle fan speed open-loop control program.

10. A computer-readable storage medium storing a computer program, characterized in that, The readable storage medium stores a vehicle fan speed open-loop control program, which, when executed by a processor, implements the steps of the vehicle fan speed open-loop control method as described in any one of claims 1-7.

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