An automatic defogging control method, device and vehicle

Abstract

The automatic defogging control method, device and vehicle provided by the embodiment of the present application relate to the defogging technical field. The automatic defogging control method can obtain a defogging index; according to a mapping relationship between the defogging index and a fogging risk level, a target fogging risk level corresponding to the defogging index is determined; and according to the target fogging risk level, the position of a circulating air door, the gear of a blower, the state of a compressor and / or the opening degree of a mode air door are selected to be regulated. Thus, the present application implements hierarchical selective regulation according to the target fogging risk level, which can timely intervene and quickly inhibit the generation of fog in the early stage of fogging, solve the problems of response lag and insufficient working condition coverage, and avoid starting high-energy-consumption components too early when there is no fogging risk or the risk is low, thereby effectively reducing redundant energy consumption and improving the endurance performance of the vehicle.

Description

Technical Field

[0001] This invention relates to the field of defogging technology, and more specifically, to an automatic defogging control method, device, and vehicle. Background Technology

[0002] With the continuous development of vehicle technology and the increasing demand from users for intelligent vehicle functions, vehicles are now generally equipped with automatic defogging functions.

[0003] However, the inventors found that the automatic defogging logic in automobiles is rather crude in related technologies. The defogging strategy is directly calibrated based solely on the values ​​of the three-in-one temperature and humidity sensor, resulting in a delayed defogging response or incomplete coverage of operating conditions. Often, the defogging logic is only activated when a large area of ​​the cabin is fogged up, affecting driving safety. Alternatively, some related components may be activated too early, causing unnecessary energy loss and reducing the vehicle's range. Summary of the Invention

[0004] The present invention aims to provide an automatic defogging control method, device and vehicle that can solve the driving safety hazards caused by delayed response or incomplete coverage of operating conditions, as well as the problems of increased energy consumption and reduced range caused by premature activation of some components.

[0005] The embodiments of the present invention can be implemented as follows: In a first aspect, the present invention provides an automatic defogging control method, comprising: Obtain the defogging index; where the defogging index is the sum of the coefficients of the fresh air volume coefficient, the moisture load coefficient, and the windshield fogging risk coefficient; Based on the mapping relationship between the defogging index and the fogging risk level, the target fogging risk level corresponding to the defogging index is determined; Based on the target fogging risk level, selectively adjust the position of the circulating damper, the blower speed, the compressor status, and / or the mode damper opening.

[0006] In an optional implementation, the step of obtaining the defogger index includes: Obtain the blower speed, recirculation damper position, vehicle speed, rainfall, intake air temperature, evaporator temperature, and the total number of open doors and windows; The first compensation coefficient is determined based on the blower speed, the position of the circulating damper, the vehicle speed, and the amount of rainfall. The second compensation coefficient is determined based on the blower speed, inlet air temperature, and evaporator temperature. The third compensation coefficient is determined based on the total number of opened doors and windows and the amount of rainfall. The fresh air volume coefficient is determined based on the sum of the first compensation coefficient, the second compensation coefficient, and the third compensation coefficient.

[0007] In an optional implementation, the step of determining the first compensation coefficient based on the blower speed, the position of the circulating damper, the vehicle speed, and the rainfall includes: Based on the mapping relationship between blower speed and basic air volume coefficient, the mapping relationship between circulation damper position and first correction coefficient, the mapping relationship between vehicle speed and second correction coefficient, and the mapping relationship between rainfall and third correction coefficient, the target basic air volume coefficient, target first correction coefficient, target second correction coefficient, and target third correction coefficient are determined respectively. The first compensation coefficient is determined by multiplying the target basic air volume coefficient, the target first correction coefficient, the target second correction coefficient, and the target third correction coefficient.

[0008] In an optional implementation, the step of determining the second compensation coefficient based on the blower speed, inlet air temperature, and evaporator temperature includes: Based on the mapping relationship between the blower speed and the basic air volume coefficient, and the mapping relationship between the difference between the inlet air temperature and the evaporator temperature and the fourth correction coefficient, the target basic air volume coefficient and the fourth correction coefficient are determined respectively. The second compensation coefficient is determined by multiplying the target basic air volume coefficient and the target fourth correction coefficient.

[0009] In an optional implementation, the step of determining the third compensation coefficient based on the total number of opened doors and windows and the amount of rainfall includes: Based on the mapping relationship between rainfall and the third correction factor, and the mapping relationship between the total number of open doors and windows and the additional air volume factor, the target third correction factor and the target additional air volume factor are determined respectively. The third compensation coefficient is determined by multiplying the third correction coefficient and the target additional air volume coefficient.

[0010] In an optional implementation, the step of obtaining the defogger index includes: Obtain the number of passengers and the rate of change in absolute humidity; Based on the mapping relationship between the number of drivers and passengers and the driver and passenger coefficient, as well as the mapping relationship between the absolute humidity change rate and the rate coefficient, the target driver and passenger coefficient and the target rate coefficient are determined respectively. The wet load factor is determined based on the sum of the driver / passenger factor and the rate factor.

[0011] In an optional implementation, the step of obtaining the defogger index includes: Get the windshield temperature, dew point temperature, and outside temperature; The target ambient temperature correction factor is determined based on the mapping relationship between the outside temperature and the ambient temperature correction factor. The risk factor for windshield fogging is determined by multiplying the difference between the windshield temperature and the dew point temperature by the target ambient temperature correction factor.

[0012] In optional implementations, the fogging risk levels include Level 1, Level 2, Level 3, Level 4, and Level 5; Based on the target fogging risk level, the steps for selectively adjusting the position of the recirculation damper, the blower speed, the compressor status, and / or the mode damper opening include: When the target fogging risk level is Level 1, maintain the current circulation damper position, blower speed, compressor operating status, and mode damper opening. When the target fogging risk level is level 2, adjust the recirculation damper to the full external circulation position based on the level 1 corresponding state; When the target fogging risk level is level three, based on the level two corresponding state, start the compressor or increase the operating frequency of the compressor to reduce the surface temperature of the evaporator to the preset surface temperature. When the target fogging risk level is level four, adjust the mode damper opening to be within the range of foot defrost opening, based on the corresponding level three state. When the target fogging risk level is level 5, adjust the blower speed to the preset level based on the level 4 corresponding state.

[0013] In a second aspect, the present invention provides an automatic defogging control device, comprising: The acquisition module is used to acquire the defogging index; wherein, the defogging index is the sum of the coefficients of the fresh air volume coefficient, the wet load coefficient, and the windshield fogging risk coefficient; The first determining module is used to determine the target fogging risk level corresponding to the defogging index based on the mapping relationship between the defogging index and the fogging risk level. The second determining module is used to selectively adjust the position of the circulating damper, the blower speed, the compressor status, and / or the mode damper opening based on the target fogging risk level.

[0014] Thirdly, the present invention provides a vehicle including a controller for executing computer instructions to implement an automatic defogging control method as described in any of the foregoing embodiments.

[0015] The beneficial effects of the automatic defogging control method, device, and vehicle provided in the embodiments of the present invention include: The automatic defogging control method, device, and vehicle provided in this invention embodiment can acquire a defogging index; determine the target fogging risk level corresponding to the defogging index based on the mapping relationship between the defogging index and the fogging risk level; and selectively adjust the position of the recirculation damper, the blower speed, the compressor status, and / or the mode damper opening according to the target fogging risk level. Therefore, this invention implements graded selective control based on the target fogging risk level, which can intervene promptly in the early stages of fogging and quickly suppress fog formation, solving the problems of response lag and insufficient operating condition coverage. It also avoids premature activation of high-energy-consuming components when there is no fogging risk or the risk is low, thereby effectively reducing redundant energy consumption and improving the overall vehicle range. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a flowchart illustrating an automatic defogging control method according to an embodiment of the present invention. Figure 2 for Figure 1 A flowchart illustrating sub-steps S310-S350 of the automatic defogging control method in the figure; Figure 3 for Figure 1 A flowchart illustrating sub-steps S110-S130 of the automatic defogging control method in the figure; Figure 4 for Figure 3 A flowchart illustrating sub-steps S121-S123 of sub-step 120 in the automatic defogging control method; Figure 5 This is a mapping diagram showing the relationship between the blower duty cycle and the corresponding basic air volume coefficient; Figure 6 This is a mapping diagram of vehicle speed and the second correction factor under external circulation conditions; Figure 7 This is a mapping diagram between rainfall and the third correction factor; Figure 8 for Figure 3 A flowchart illustrating sub-steps S131-S133 of sub-step 130 in the automatic defogging control method; Figure 9 This is a mapping diagram showing the relationship between the difference between the inlet air temperature and the evaporator temperature and the fourth correction factor. Figure 10 for Figure 3 A flowchart illustrating sub-steps S141-S143 of sub-step 140 in the automatic defogging control method. Figure 11 A graph showing the mapping relationship between the total number of open car doors and windows and the additional air volume coefficient; Figure 12 for Figure 1 A flowchart illustrating sub-steps S161-S165 of the automatic defogging control method in the figure; Figure 13 A mapping relationship between the absolute humidity change rate and the rate coefficient; Figure 14 for Figure 1 A flowchart illustrating sub-steps S171-S175 of the automatic defogging control method in the figure; Figure 15 A mapping diagram showing the relationship between the vehicle outside temperature and the ambient temperature correction factor; Figure 16 This is a schematic block diagram of the automatic defogging control device provided in an embodiment of the present invention.

[0018] Icons: 010 - Automatic defogging control device; 011 - Acquisition module; 012 - First determination module; 013 - Second determination module. Detailed Implementation

[0019] Automatic defogging in related technologies either has a delayed response or incomplete coverage of operating conditions, affecting driving safety; or it starts too early, causing unnecessary energy loss and reducing the vehicle's range.

[0020] To address the aforementioned problems, this invention provides an automatic defogging control method, device, and vehicle that can resolve driving safety hazards caused by delayed response or incomplete coverage of operating conditions, as well as the problems of increased energy consumption and reduced range caused by premature activation of some components.

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0023] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0024] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0025] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0026] It should be noted that, where there is no conflict, the features in the embodiments of the present invention can be combined with each other.

[0027] The following describes in detail the overall structure, working principle, and technical effects of the automatic defogging control device 010 provided by the present invention, as well as the detailed steps, implementation principle, and technical effects of the supporting automatic defogging control method, through embodiments and in conjunction with the accompanying drawings.

[0028] Please see Figure 1 This invention provides an automatic defogging control method for vehicles. It can classify the severity of fogging on the entire vehicle and adopt corresponding defogging control strategies according to the differences in levels, thereby realizing intelligent automatic defogging and solving the driving safety hazards caused by delayed response or incomplete coverage of operating conditions, as well as the problems of increased energy consumption and reduced range caused by premature activation of some components.

[0029] The automatic defogging control method provided in this embodiment may include the following steps S100-S300.

[0030] Step S100: Obtain the defogging index.

[0031] In step S100, the defogging index is the sum of the coefficients of the fresh air volume coefficient, the moisture load coefficient, and the windshield fogging risk coefficient. The fresh air volume coefficient represents the total fresh air volume of the vehicle and is used as a positive feedforward to assess the fogging risk; the moisture load coefficient represents the moisture load inside the vehicle and is used as a negative feedforward to assess the fogging risk. Combined with the windshield fogging risk coefficient, these two coefficients can be used to assess the severity of fogging in the entire vehicle.

[0032] Step S200: Based on the mapping relationship between the defogging index and the fogging risk level, determine the target fogging risk level corresponding to the defogging index.

[0033] Step S300: Based on the target fogging risk level, selectively adjust the position of the circulating damper, the blower speed, the compressor status, and / or the mode damper opening.

[0034] In step S300, graded selective control is implemented according to the target fogging risk level. This can intervene in a timely manner in the early stage of fogging and quickly suppress fog formation, solving the problems of response lag and insufficient operating condition coverage. It can also avoid starting high-energy-consuming components too early when there is no fogging risk or the risk is low, thereby effectively reducing redundant energy consumption and improving the overall vehicle range performance.

[0035] Therefore, the automatic defogging control method provided by this invention abandons the traditional approach of relying solely on a single sensor (such as a three-in-one temperature and humidity sensor) to directly trigger the defogging logic, effectively avoiding the resulting response lag or premature intervention problems, significantly improving the timeliness of defogging initiation and the accuracy of judgment, thereby enhancing driving safety.

[0036] Specifically, the position of the circulating damper, the blower speed, the compressor status, and the mode damper opening are combined using differentiated strategies for different fogging risk levels. In some embodiments of the present invention, the fogging risk levels include Level 1, Level 2, Level 3, Level 4, and Level 5. Accordingly, please refer to... Figure 2 Step S300 includes the following steps: Step S310: When the target fogging risk level is Level 1, maintain the current circulation damper position, blower speed, compressor operating status, and mode damper opening.

[0037] In step S310, when the target fogging risk level is level one, it indicates that the current fogging risk is low, the system maintains its original operating state, and does not trigger any fogging-related actions.

[0038] Step S320: When the target fogging risk level is level 2, adjust the position of the recirculation damper to the fully external circulation position based on the level 1 corresponding state.

[0039] In step S320, by changing the position of the recirculation damper, the proportion of fresh air is increased, thereby increasing the fresh air volume, effectively diluting the humid air inside the vehicle and reducing the relative humidity, thus achieving pre-fogging intervention without starting high-energy-consuming components such as the compressor.

[0040] Step S330: When the target fogging risk level is level three, based on the level two corresponding state, start the compressor or increase the operating frequency of the compressor so that the surface temperature of the evaporator drops to the preset surface temperature.

[0041] In step S330, humid air inside the vehicle is drawn into the air conditioning system and flows over the surface of the evaporator. Since the surface temperature of the evaporator is much lower than the dew point temperature of the air, water vapor condenses on its surface and is then discharged outside the vehicle through the drain pipe. Optionally, the temperature of the evaporator is monitored in real time by a temperature sensor installed on its surface, and the preset surface temperature can be set to 3°C.

[0042] Step S340: When the target fogging risk level is level four, adjust the mode damper opening to the range of foot defrost opening based on the level three corresponding state.

[0043] In step S340, the mode damper of the car's air conditioning system is used to control the airflow mode. By adjusting the opening of the mode damper, the airflow mode of the car's air conditioning system is adjusted. The foot defrost mode is a combined airflow mode that simultaneously delivers air to the front foot area and the windshield. This means that, on the one hand, this mode continuously delivers dry, hot air to the low-temperature glass to suppress fogging; on the other hand, the warm air flows from bottom to top, which is more in line with the human body's thermal comfort needs than blowing directly on the face.

[0044] Step S350: When the target fogging risk level is level 5, adjust the blower speed to the preset speed based on the level 4 corresponding state.

[0045] In step S350, the blower speed is adjusted to a preset speed to enhance airflow velocity and heat exchange intensity, thereby accelerating the evaporation and replacement of moisture on the windshield surface and improving the defogging response speed and effectiveness under extreme fogging conditions. Optionally, for a blower with eight adjustable speeds, the preset speed is the fourth speed.

[0046] Based on the above-mentioned hierarchical control logic, a seamless defogging effect is achieved. That is, when the risk of fogging is low, no obvious intervention is triggered as much as possible so that the user is unaware of it; dilution control is implemented in advance during the stage of slow humidity increase; and defogging can be responded to in a timely manner when the humidity inside the vehicle suddenly increases, thus taking into account both passenger cabin comfort and driving safety.

[0047] Furthermore, it should be noted that, as mentioned above, the defogging index is composed of both positive and negative feedforward values, used to comprehensively assess the risk of fogging. A higher defogging index indicates a stronger dilution effect from fresh air and a lower risk of fogging; conversely, a lower defogging index reflects a more significant tendency for moisture load or condensation on glass, and a higher risk of fogging. Therefore, the defogging index is divided into five intervals from high to low, corresponding to target fogging risk levels one through five.

[0048] For example, when the defogging index is <1.5, it corresponds to a level 5 fog risk level; when the defogging index is 1.5~2.3, it corresponds to a level 4 fog risk level; when the defogging index is 2.3~3.5, it corresponds to a level 3 fog risk level; when the defogging index is 3.5~5.4, it corresponds to a level 2 fog risk level; and when the defogging index is ≥7.2, it corresponds to a level 1 fog risk level.

[0049] Regarding the fresh air volume coefficient, in the optional embodiments, such as Figure 3 As shown, the steps to obtain the defogger index include: Step S110: Obtain the blower speed, recirculation damper position, vehicle speed, rainfall, intake air temperature, evaporator temperature, and the total number of open doors and windows.

[0050] Step S120: Determine the first compensation coefficient based on the blower speed, the position of the circulating damper, the vehicle speed, and the rainfall.

[0051] In step S120, the blower speed directly determines the total air volume; the position of the recirculation damper determines the proportion of fresh air; vehicle speed and rainfall also have a compensating effect on the fresh air volume. Therefore, by looking up the above four sets of parameters in the MAP table, a first compensation coefficient representing the fresh air compensation can be obtained.

[0052] Step S130: Determine the second compensation coefficient based on the blower speed, inlet air temperature, and evaporator temperature.

[0053] In step S130, the dehumidification compensation amount is calculated from the difference between the evaporator temperature and the inlet air temperature. The evaporator temperature is taken from the measured value of a thermistor; the inlet air temperature is dynamically selected based on the position of the circulation damper, i.e., the ambient temperature sensor value is used for external circulation, the internal temperature sensor value is used for internal circulation, and the average value of the two is used for mixed internal and external circulation. The difference between the evaporator temperature and the inlet air temperature, along with the blower speed, are input into the corresponding MAP table for lookup to obtain the second compensation coefficient characterizing the dehumidification compensation.

[0054] Step S140: Determine the third compensation coefficient based on the total number of opened doors and windows and the amount of rainfall.

[0055] In step S140, the opening status of the doors and windows is used to characterize the amount of fresh air introduced. This fresh air volume is combined with the rainfall, and a third compensation coefficient characterizing other fresh air compensations is obtained through a lookup table or mapping relationship. It should be noted that the opening and closing status of the doors and windows is determined by the high or low level signals output by their respective Hall sensors, including four doors and four windows, for a total of eight signals.

[0056] Step S150: Determine the fresh air volume coefficient based on the sum of the first compensation coefficient, the second compensation coefficient, and the third compensation coefficient.

[0057] In step S150, based on the above three compensation coefficients, the fresh air volume coefficient can dynamically and accurately characterize the actual fresh air introduction capacity, thereby improving the accuracy of the defogging index in characterizing the actual fogging risk and enhancing the reliability of subsequent fogging risk level determination.

[0058] Furthermore, such as Figure 4 As shown, the steps for determining the first compensation coefficient (i.e., step S120) based on the blower speed, the position of the circulating damper, the vehicle speed, and the rainfall include: Step S121: Based on the mapping relationship between the blower speed and the basic air volume coefficient, the mapping relationship between the circulating damper position and the first correction coefficient, the mapping relationship between the vehicle speed and the second correction coefficient, and the mapping relationship between the rainfall and the third correction coefficient, the target basic air volume coefficient, the target first correction coefficient, the target second correction coefficient, and the target third correction coefficient are determined respectively.

[0059] The blower speed is obtained based on the duty cycle signal fed back by the ITMS (Integrated Thermal Management System), and the mapping relationship between it and the basic air volume coefficient is as follows: Figure 5 As shown in Table 1. Table 1 lists the mapping relationship between the duty cycle of some blowers and the corresponding basic air volume coefficient.

[0060] Table 1: Mapping relationship between blower speed and basic air volume coefficient.

[0061]

[0062] In this table, K blower The base air volume coefficient is characterized by a blower duty cycle ranging from 0% to 100%, corresponding to a voltage signal of 0 to 13V. As shown in the table, the larger the blower duty cycle, the higher the corresponding speed setting, and the larger the base air volume coefficient.

[0063] The position of the circulating damper is also obtained based on the duty cycle signal fed back by ITMS, and the mapping relationship between it and the first correction coefficient is shown in Table 2.

[0064] Table 2: Mapping relationship between the position of the circulating damper and the first correction coefficient.

[0065]

[0066] In this table, K inlet Characterized by the first correction factor. As shown in the table, when the recirculation damper is in the internal recirculation position, K... inlet K is 0; when in mixed internal and external mode, K inlet It is 0.5; when in the outer loop position, Kinlet The value is 1. That is, there is less fresh air during internal circulation and more fresh air during external circulation.

[0067] Vehicle speed signals are directly acquired via the CAN bus, with wheel angular velocities collected by wheel speed sensors and calculated by ESP. Furthermore, the mapping relationship between vehicle speed and the second correction coefficient depends on the state of the recirculation damper, and is divided into two cases: complete internal recirculation and complete external recirculation. In the complete internal recirculation state, the mapping relationship shown in Table 3 is used; in the complete external recirculation state, the mapping relationship shown in Table 3 is used. Figure 6 The mapping relationship is shown in Table 4.

[0068] Table 3: Mapping relationship between vehicle speed and second correction factor under internal circulation mode.

[0069]

[0070] Table 4: Mapping relationship between vehicle speed and second correction coefficient under external circulation mode.

[0071]

[0072] In Tables 3 and 4, K spd The second correction coefficient is used to characterize the air conditioner's operation. Based on the above, when the air conditioner is in full recirculation mode, the second correction coefficient remains constant at 1 regardless of vehicle speed. However, when the air conditioner is in full external recirculation mode, the second correction coefficient increases monotonically with increasing vehicle speed; the faster the vehicle speed, the greater the actual fresh air volume.

[0073] Rainfall signals are acquired directly via the LIN bus. Rainfall levels are typically divided into 1 to 12. Rainfall is determined by the intensity of reflected light emitted by the rain sensor. The signal is transmitted directly from the sensor to the LIN bus. The mapping relationship between rainfall and the third correction factor is as follows: Figure 7 As shown in Table 5.

[0074] Table 5: Mapping relationship between rainfall and the third correction factor.

[0075]

[0076] In this table, K rain The third correction factor is used to characterize the rainfall level. As shown in the table, the higher the rainfall level, the more humid air enters the vehicle, and the lower the equivalent fresh air volume.

[0077] Step S123: Determine the first compensation coefficient based on the product of the target basic air volume coefficient, the target first correction coefficient, the target second correction coefficient, and the target third correction coefficient.

[0078] In step S123, the first compensation coefficient = K blower ×K inlet ×K spd×K rain The base air volume coefficient is uniquely determined by the blower speed setting and serves as the baseline input for calculating the fresh air volume. The first, second, and third correction coefficients are all used to correct the base air volume. Specifically, the first correction coefficient reflects the effect of the recirculation damper position on the proportion of fresh air in the base air volume; the second correction coefficient reflects the enhanced effect of the actual intake air volume under external recirculation conditions at vehicle speed; and the third correction coefficient reflects the weakening effect of increased rainfall on the dehumidification effect of the base air volume.

[0079] Furthermore, such as Figure 8 As shown, the step of determining the second compensation coefficient (i.e., step S130) based on the blower speed, inlet air temperature, and evaporator temperature includes: Step S131: Based on the mapping relationship between the blower speed and the basic air volume coefficient, and the mapping relationship between the difference between the inlet air temperature and the evaporator temperature and the fourth correction coefficient, the target basic air volume coefficient and the fourth correction coefficient are confirmed respectively.

[0080] The mapping relationship between the blower speed and the basic air volume coefficient is shown in Table 1 above, and the mapping relationship between the difference between the inlet air temperature and the evaporator temperature and the fourth correction coefficient is shown in Table 1 above. Figure 9 As shown in Table 6. Table 6 lists the mapping relationship between the difference between some inlet air temperature and evaporator temperature and the fourth correction factor.

[0081] Table 6: Mapping relationship between the difference between inlet air temperature and evaporator temperature and the fourth correction factor.

[0082]

[0083] In this table, K △evap The fourth correction factor is used to characterize the evaporator's cooling force on the humid air. The greater the temperature difference, the stronger the actual dehumidification capacity, and the higher the value of the fourth correction factor.

[0084] Step S133: Determine the second compensation coefficient based on the product of the target basic air volume coefficient and the target fourth correction coefficient.

[0085] In step S133, the second compensation coefficient = K blower ×K △evap The base air volume coefficient is uniquely determined by the blower speed and serves as the baseline input for calculating the fresh air volume. The fourth correction coefficient is used to dynamically reflect the dehumidification capacity of the evaporator and is multiplied by the base air volume to jointly characterize the actual dehumidification of the air conditioning system under the current operating conditions.

[0086] Furthermore, such as Figure 10 As shown, the steps for determining the third compensation coefficient (i.e., step S140) based on the total number of opened doors and windows and the amount of rainfall include: Step S141: Based on the mapping relationship between rainfall and the third correction coefficient, and the mapping relationship between the total number of open doors and windows and the additional air volume coefficient, confirm the target third correction coefficient and the target additional air volume coefficient respectively.

[0087] The mapping relationship between rainfall and the third correction factor is shown in Table 5; the mapping relationship between the total number of open doors and windows and the additional air volume factor is shown in Table 5. Figure 11 As shown in Table 7.

[0088] Table 7: Mapping relationship between the total number of open doors and windows and the additional air volume coefficient.

[0089]

[0090] In this table, Kdoor represents the additional air volume coefficient. As can be seen from the table, the more windows and doors are open, the greater the fresh air volume, and the higher the Kdoor value.

[0091] Step S143: Determine the third compensation coefficient based on the product of the third correction coefficient and the target additional air volume coefficient.

[0092] In step S143, the third compensation coefficient = K rain ×Kdoor. The additional air volume coefficient represents the amount of fresh air entering the vehicle through the doors and / or windows; the third correction factor reflects the weakening effect of increased rainfall on the dehumidification of this additional fresh air.

[0093] Regarding the wet load factor, in the optional embodiments, such as Figure 12 As shown, the steps to obtain the defogger index include: Step S161: Obtain the number of passengers and the rate of change of absolute humidity.

[0094] In step S161, the number of occupants is obtained based on the seat belt signal; this signal is transmitted via CAN bus or LIN bus, and is typically output by a microswitch on the seat, providing a high / low level switching signal. The absolute humidity change rate is calculated from the temperature and relative humidity collected by the in-vehicle temperature and humidity sensor; this sensor signal is typically transmitted directly to the air conditioning controller via a hardwired connection.

[0095] Specifically, based on the known temperature T, e is calculated using the Magnus formula. sat (T): .

[0096] In the formula, e sat (T) is the saturated water vapor pressure at temperature T, in hPa.

[0097] Subsequently, based on the known temperature T and saturated vapor pressure e sat (T), ρ is calculated by deriving the ideal gas law. sat (T): .

[0098] In the formula, ρ sat (T) represents the saturated water vapor density at temperature T, in g / m³.

[0099] Subsequently, based on relative humidity RH and saturated water vapor density ρ sat (T), calculate AH: .

[0100] In the formula, AH represents absolute humidity, in g / m³; RH represents relative humidity, in %; ρ sat (T) represents the saturated water vapor density at temperature T, in g / m³.

[0101] The rate of change of absolute humidity is calculated using a combination of timed sampling, first-order difference, and first-order filtering. For example, the vehicle interior temperature and relative humidity are sampled every second, and the absolute humidity (AH) at the corresponding moment is calculated in real time. The instantaneous rate of change is obtained by dividing the difference between the absolute humidity at the current moment and the previous moment by the sampling interval (1 second). .

[0102] In the formula, AH n AH represents the absolute humidity at the current moment. n-1 Δt represents the absolute humidity at the previous moment; Δt represents the sampling interval (seconds).

[0103] Then, apply a first-order low-pass filter to the instantaneous rate of change to obtain a smoothed growth rate: .

[0104] In the formula, sRate n The current smoothed growth rate α represents the current filtered rate; the filter coefficient is set to 0.2; rate n Characterizes the instantaneous rate of change currently being calculated.

[0105] Step S163: Based on the mapping relationship between the number of drivers and passengers and the driver and passenger coefficient, and the mapping relationship between the absolute humidity change rate and the rate coefficient, determine the target driver and passenger coefficient and the target rate coefficient respectively.

[0106] The mapping relationship between the number of drivers and passengers and the driver and passenger coefficient is shown in Table 8, and the mapping relationship between the absolute humidity change rate and the rate coefficient is shown in Table 8. Figure 13 As shown in Table 9.

[0107] Table 8: Mapping Relationship Between Number of Drivers and Passengers and Driver / Passenger Coefficient

[0108] In this table, K pass This represents the occupant coefficient. The more seatbelt signals there are, the more people are in the vehicle, and the greater the steady-state wet load.

[0109] Table 9: Mapping relationship between absolute humidity change rate and rate coefficient.

[0110]

[0111] In this table, K AH The rate coefficient characterizes the rate of change in absolute humidity. It reflects the rapid change in moisture load. A rapid increase in this value usually indicates a large increase in moisture vapor within a short period due to people breathing, talking, or engaging in other activities; in such cases, dehumidification should be intensified in advance to prevent sudden fogging.

[0112] Step S165: Determine the wet load coefficient based on the sum of the driver / passenger coefficient and the rate coefficient.

[0113] In step S165, the wet load factor = K AH +K pass Among them, the passenger coefficient reflects the steady-state moisture load caused by the number of passengers, and the rate coefficient reflects the transient moisture load caused by the rate of change of humidity. The sum of the two can comprehensively characterize the current overall moisture load level inside the vehicle.

[0114] Regarding the risk factor of windshield fogging, in the optional embodiments, such as... Figure 14 As shown, the steps to obtain the defogger index include: Step S171: Obtain the windshield temperature, dew point temperature, and outside temperature.

[0115] In step S171, the vehicle interior temperature and relative humidity can be obtained through the vehicle interior temperature and humidity sensor; the vehicle exterior temperature (i.e., ambient temperature) is collected by the exterior temperature sensor; the dew point temperature is calculated in real time by ITMS based on the Magnus formula.

[0116] In the formula, a = 17.625; b = 243.04; T is the interior temperature (°C); RH is the interior relative humidity (%); γ is based on the formula: (T,RH) = ln(RH / 100) + a T / (b+T) is obtained.

[0117] Step S173: Determine the target ambient temperature correction coefficient based on the mapping relationship between the outside temperature and the ambient temperature correction coefficient.

[0118] The mapping relationship between the vehicle exterior temperature and the ambient temperature correction factor is as follows: Figure 15 As shown in Table 10. Table 10 lists some of the mapping relationships between outside vehicle temperature and ambient temperature correction factors.

[0119] Table 10: Mapping relationship between outside temperature and ambient temperature correction factor.

[0120]

[0121] In this table, K amb Characterizes the ambient temperature correction factor. The lower the outside temperature, the lower the surface temperature of the windshield; when the humid and hot air inside the vehicle comes into contact with the glass surface, which is below its dew point temperature, water vapor is more likely to condense, thus increasing the risk of fogging.

[0122] Step S175: Based on the product of the difference between the windshield temperature and the dew point temperature and the target ambient temperature correction coefficient, the windshield fogging risk factor is determined.

[0123] In step S175, the windshield fogging risk factor = (glass temperature - dew point temperature) × K amb The difference between the glass temperature and the dew point temperature is a direct basis for judging the risk of fogging and a key feedback signal in actual vehicle control. However, because the sensor is installed in a fixed position, it can only obtain the local temperature of the glass, making it difficult to reflect the temperature distribution of the entire glass surface. Furthermore, the tendency to fog varies under different outside temperature conditions for the same temperature difference. Therefore, it is necessary to correct for the above temperature difference by incorporating the outside temperature to improve the accuracy of fogging risk assessment.

[0124] Please see Figure 16 To execute the possible steps of the automatic defogging control method provided in the above embodiments, this embodiment of the invention provides an automatic defogging control device 010, applied to a vehicle, for executing the above-described automatic defogging control method. It should be noted that the basic principle and technical effects of the automatic defogging control device 010 provided in this embodiment are basically the same as those in the above embodiments. For the sake of brevity, any parts not mentioned in this embodiment can be referred to the corresponding content in the above embodiments.

[0125] The automatic defogging control device 010 provided by the present invention includes an acquisition module 011, a first determination module 012, and a second determination module 013.

[0126] The acquisition module 011 is used to acquire the defogging index; the defogging index is the sum of the coefficients of the fresh air volume coefficient, the wet load coefficient, and the windshield fogging risk coefficient.

[0127] In this embodiment, the acquisition module 011 is used to execute step S100 and its sub-steps in the above method to achieve the corresponding technical effect.

[0128] The first determining module 012 is used to determine the target fogging risk level corresponding to the defogging index based on the mapping relationship between the defogging index and the fogging risk level.

[0129] In this embodiment, the first determining module 012 is used to execute step S200 and its sub-steps in the above method to achieve the corresponding technical effect.

[0130] The second determining module 013 is used to selectively adjust the position of the circulating damper, the blower speed, the compressor status, and / or the mode damper opening based on the target fogging risk level.

[0131] In this embodiment, the second determining module 013 is used to execute step S300 and its sub-steps in the above method to achieve the corresponding technical effect.

[0132] In addition, embodiments of the present invention also provide a vehicle, including a controller, which executes computer instructions to implement the automatic defogging control method provided in the embodiments of the present invention.

[0133] The controller can be an integrated circuit chip with signal processing capabilities. The aforementioned controller can be a general-purpose processor, including a central processing unit (CPU), or a microcontroller, microcontroller unit (MCU), complex programmable logic device (CPLD), field-programmable gate array (FPGA), application-specific integrated circuit (ASIC), embedded ARM, etc. The controller can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this invention.

[0134] In one feasible implementation, the controller may further include a memory for storing program instructions executable by the controller. For example, the automatic defogging control device 010 provided in this application embodiment includes at least one instruction that can be stored in the memory in the form of software or firmware. The memory may be a separate external memory, including but not limited to Random Access Memory (RAM), Read Only Memory (ROM), Programmable Read-Only Memory (PROM), Erasable Programmable Read-Only Memory (EPROM), and Electrically Erasable Programmable Read-Only Memory (EEPROM). The memory may also be integrated with the controller, for example, the memory may be integrated with the controller within the same chip.

[0135] In summary, the automatic defogging control method, device, and vehicle provided in this invention can acquire a defogging index; determine the target fogging risk level corresponding to the defogging index based on the mapping relationship between the defogging index and the fogging risk level; and selectively adjust the position of the recirculation damper, the blower speed, the compressor status, and / or the mode damper opening based on the target fogging risk level. Therefore, this invention implements graded selective control based on the target fogging risk level, which can intervene promptly in the early stages of fogging and quickly suppress fog formation, solving the problems of response lag and insufficient operating condition coverage. It can also avoid prematurely activating high-energy-consuming components when there is no fogging risk or the risk is low, thereby effectively reducing redundant energy consumption and improving the overall vehicle range.

[0136] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative; for example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0137] In addition, the functional modules in the various embodiments of the present invention can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0138] If the functionality is implemented as a software module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0139] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. An automatic defogging control method, characterized in that, include: Obtain the defogging index; wherein the defogging index is the sum of the coefficients of the fresh air volume coefficient, the moisture load coefficient, and the windshield fogging risk coefficient; Based on the mapping relationship between the defogging index and the fogging risk level, the target fogging risk level corresponding to the defogging index is determined; Based on the target fogging risk level, selectively adjust the position of the circulating damper, the blower speed, the compressor status, and / or the mode damper opening.

2. The automatic defogging control method according to claim 1, characterized in that, The steps for obtaining the defogging index include: Obtain the blower speed, recirculation damper position, vehicle speed, rainfall, intake air temperature, evaporator temperature, and the total number of open doors and windows; The first compensation coefficient is determined based on the blower speed, the circulating damper position, the vehicle speed, and the rainfall. The second compensation coefficient is determined based on the blower speed, the inlet air temperature, and the evaporator temperature. Based on the total number of opened doors and windows and the amount of rainfall, a third compensation coefficient is determined; The fresh air volume coefficient is determined based on the sum of the first compensation coefficient, the second compensation coefficient, and the third compensation coefficient.

3. The automatic defogging control method according to claim 2, characterized in that, The step of determining the first compensation coefficient based on the blower speed, the circulating damper position, the vehicle speed, and the rainfall includes: Based on the mapping relationship between the blower speed and the basic air volume coefficient, the mapping relationship between the circulating damper position and the first correction coefficient, the mapping relationship between the vehicle speed and the second correction coefficient, and the mapping relationship between the rainfall and the third correction coefficient, the target basic air volume coefficient, the target first correction coefficient, the target second correction coefficient, and the target third correction coefficient are determined respectively. The first compensation coefficient is determined based on the product of the target basic air volume coefficient, the target first correction coefficient, the target second correction coefficient, and the target third correction coefficient.

4. The automatic defogging control method according to claim 2, characterized in that, The step of determining the second compensation coefficient based on the blower speed, the inlet air temperature, and the evaporator temperature includes: Based on the mapping relationship between the blower speed and the basic air volume coefficient, and the mapping relationship between the difference between the inlet air temperature and the evaporator temperature and the fourth correction coefficient, the target basic air volume coefficient and the fourth correction coefficient are determined respectively. The second compensation coefficient is determined based on the product of the target basic air volume coefficient and the target fourth correction coefficient.

5. The automatic defogging control method according to claim 2, characterized in that, The step of determining the third compensation coefficient based on the total number of opened doors and windows and the amount of rainfall includes: Based on the mapping relationship between the rainfall and the third correction coefficient, and the mapping relationship between the total number of open doors and windows and the additional air volume coefficient, the target third correction coefficient and the target additional air volume coefficient are determined respectively. The third compensation coefficient is determined based on the product of the third correction coefficient and the target additional air volume coefficient.

6. The automatic defogging control method according to claim 1, characterized in that, The steps for obtaining the defogging index include: Obtain the number of passengers and the rate of change in absolute humidity; Based on the mapping relationship between the number of drivers and passengers and the driver and passenger coefficient, and the mapping relationship between the absolute humidity change rate and the rate coefficient, the target driver and passenger coefficient and the target rate coefficient are determined respectively. The wet load coefficient is determined based on the sum of the driver / passenger coefficient and the rate coefficient.

7. The automatic defogging control method according to claim 1, characterized in that, The steps for obtaining the defogging index include: Get the windshield temperature, dew point temperature, and outside temperature; Based on the mapping relationship between the outside temperature and the ambient temperature correction coefficient, the target ambient temperature correction coefficient is determined; The risk factor for windshield fogging is determined by multiplying the difference between the windshield temperature and the dew point temperature by the target ambient temperature correction factor.

8. The automatic defogging control method according to any one of claims 1 to 7, characterized in that, The fogging risk levels are classified into five levels: Level 1, Level 2, Level 3, Level 4, and Level 5. The step of selectively adjusting the position of the circulating damper, the blower speed, the compressor status, and / or the mode damper opening based on the target fogging risk level includes: When the target fogging risk level is Level 1, maintain the current circulation damper position, blower speed, compressor operating status, and mode damper opening. When the target fogging risk level is level two, the position of the recirculation damper is adjusted to the fully external circulation position based on the level one corresponding state; When the target fogging risk level is level three, based on the level two corresponding state, the compressor is started or the operating frequency of the compressor is increased so that the surface temperature of the evaporator drops to the preset surface temperature. When the target fogging risk level is level four, based on the level three corresponding state, adjust the mode damper opening to be within the foot defrost opening range; When the target fogging risk level is level five, the blower speed is adjusted to the preset speed based on the level four corresponding state.

9. An automatic defogging control device, characterized in that, include: The acquisition module is used to acquire the defogging index; wherein the defogging index is the sum of the coefficients of the fresh air volume coefficient, the wet load coefficient, and the windshield fogging risk coefficient; The first determining module is used to determine the target fogging risk level corresponding to the defogging index based on the mapping relationship between the defogging index and the fogging risk level; The second determining module is used to selectively adjust the position of the circulating damper, the blower speed, the compressor status, and / or the mode damper opening based on the target fogging risk level.

10. A vehicle, characterized in that, It includes a controller for executing computer instructions to implement the automatic defogging control method as described in any one of claims 1 to 8.

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