Automobile automatic defogging control method and system, automobile and storage medium

Abstract

The invention relates to the technical field of automobile demisting, in particular to an automobile automatic demisting control method and system, an automobile and a storage medium. The method comprises the steps that the glass temperature, the in-automobile temperature, the dew point temperature and the in-automobile humidity are obtained; looking up a first table according to the difference between the glass temperature and the dew point temperature to obtain a first fogging probability; looking up a second table according to the difference between the in-vehicle temperature and the glass temperature to obtain a second fogging probability; looking up a third table according to the in-vehicle humidity to obtain a third fogging probability; the fogging probability is calculated according to the first fogging probability, the second fogging probability and the third fogging probability; and determining a fogging level according to the fogging probability, and carrying out defogging based on a defogging strategy corresponding to the fogging level. The problem that in the prior art, fogging cannot be prevented in advance due to inaccurate judgment of the fogging probability is solved.

Description

Technical Field

[0001] The invention relates to the technical field of automobile defogging, and in particular to an automobile automatic defogging control method, a system, an automobile and a storage medium. Background Art

[0002] With the development of new energy vehicles, automatic air-conditioning technology has also been fully popularized. Unlike traditional fuel vehicles that still use manual air-conditioning in large quantities, automatic air-conditioning has now become almost a standard configuration for new energy vehicles, and users use automatic air-conditioning in more and more scenarios. In addition to meeting the comfort needs of the passenger compartment, automatic air-conditioning also needs to meet safety needs in different scenarios.

[0003] Automatic defogger, as an important component of automatic air conditioning, can greatly affect the user experience of automatic air conditioning. Entering the defog state too early or too late, staying in the defog state for a long time, and being unable to defog effectively will all lead to a poor user experience. In addition, the appearance of large area of ​​fog on the front windshield will affect driving safety.

[0004] Currently, most commonly used automatic defogger algorithms directly use the difference between the dew point temperature and the temperature inside and outside the vehicle to control the entry and exit of automatic defogger. This method is relatively simple and has large errors in actual use. The defogger function is often triggered only after obvious fog appears on the front windshield, affecting driving safety.

[0005] For example, patent document CN103847463A discloses a control method for automatically preventing automobile fogging, which proposes to collect the humidity inside the car and the temperature inside and outside the car through a temperature and humidity acquisition module to calculate the probability of fogging, and to perform automatic defogger by controlling the blower, air intake damper, and mode damper. The specific implementation method is to collect the humidity inside the car and the temperature inside and outside the car through a temperature and humidity acquisition module, and the air conditioning controller calculates the probability of fogging according to the humidity inside the car and the temperature inside and outside the car. At the same time, the air conditioning controller controls the blower, air intake damper, and mode damper for automatic defogger, and the blower air volume, air intake damper, and mode damper perform voltage compensation according to the calculated probability. The calculation formula for the probability of fogging is: F = [H RH +C 1 -f(T Incar -T ambient )]×C 2 ÷100, where H RH is the humidity value in the car, measured by the humidity sensor in the car; T Incar is the temperature inside the car, measured by the temperature sensor inside the car; T ambient is the outside temperature value, measured by the outside temperature sensor; f(T Incar -T ambient ) is the fogging probability function obtained by experimental calibration based on the temperature difference between the inside and outside of the vehicle; C 1and C 2 is a constant, which is obtained according to the calibration of the specific vehicle model. 1 The typical value is 45°C. 2 The common typical value is 80; the f(T Incar -T ambient) The independent variable is T Incar -T ambient function. However, this method has the following main problems: first, fogging cannot be avoided when the air conditioner is not turned on; second, when the air conditioner is turned on but in ventilation or heating mode, only the blower, air inlet damper and circulation damper are controlled, and the compressor cannot be turned on, and the humidity in the car cannot be effectively reduced, and fogging cannot be avoided or effectively defogged. Or when the air conditioner is turned on and in cooling mode, although the compressor is in working state, the evaporator temperature is not actively controlled. If the evaporator temperature is high at this time, the dehumidification efficiency is low, and the front windshield cannot be effectively prevented from fogging or the defogger time after fogging is long, which affects driving safety; third, in the calculation method, only the temperature difference between the inside and outside of the car is calculated for the temperature difference to calculate the probability of fogging, which has a certain error. The fogging of the car windshield is usually caused by the high air temperature and high humidity in the car, while the temperature of the windshield is low. The moisture in the air inside the car will form fog on the windshield with lower temperature. In this calculation method, although the temperature difference between the inside and outside of the car can reflect the temperature difference between the inside temperature and the glass temperature to a certain extent, in actual use, the temperature difference between the windshield and the inside temperature corresponding to the temperature difference between the inside and outside of the car is different in different scenarios, which leads to errors in the calculation of the fogging probability.

[0006] Therefore, it is necessary to develop a new automobile automatic defog control method, system, automobile and storage medium. Summary of the invention

[0007] The object of the present invention is to provide a method, system, vehicle and storage medium for controlling automatic defog of a vehicle, so as to solve the problem in the prior art that the probability of fogging cannot be accurately determined, resulting in the inability to prevent fogging in advance.

[0008] In a first aspect, a method for controlling automatic defog of a vehicle according to the present invention comprises the following steps:

[0009] Get glass temperature, interior temperature, dew point temperature and interior humidity;

[0010] According to the difference between the glass temperature and the dew point temperature, the first fogging probability is obtained by looking up the first table;

[0011] The second fogging probability is obtained by looking up the second table according to the difference between the temperature inside the vehicle and the temperature of the glass;

[0012] According to the humidity in the car, the third fogging probability is obtained by looking up the third table;

[0013] Calculating the fogging probability according to the first fogging probability, the second fogging probability and the third fogging probability;

[0014] Determining a fogging level according to the fogging probability, and performing defogger based on a defogger strategy corresponding to the fogging level;

[0015] Wherein, the first table is a correspondence table of the difference between the glass temperature and the dew point temperature and the first fogging probability;

[0016] The second table is a table of corresponding relations between the difference between the temperature inside the vehicle and the temperature of the glass and the second fogging probability;

[0017] The third table is a correspondence table between the humidity inside the vehicle and the third fogging probability.

[0018] Optionally, the calculating the fogging probability according to the first fogging probability, the second fogging probability and the third fogging probability is specifically:

[0019] The fogging probability is equal to the sum of the first fogging probability, the second fogging probability and the third fogging probability. The accuracy of the final fogging probability can be ensured by directly adding three different fogging probabilities (ie, the first, second and third fogging probabilities) to obtain the final fogging probability.

[0020] Optionally, the fogging level includes low, medium and high levels, wherein determining the fogging level according to the fogging probability includes:

[0021] When it is determined that the fogging probability is greater than a first threshold value and less than or equal to a second threshold value, determining that the fogging level is the low level;

[0022] When it is determined that the fogging probability is greater than the second threshold and less than or equal to the third threshold, determining that the fogging level is the intermediate level;

[0023] When it is determined that the fogging probability is greater than a third threshold, determining the fogging level to be the high level;

[0024] Among them, the first threshold value < the second threshold value < the third threshold value. By setting three different threshold values ​​(and there is a clear increasing relationship between the threshold values), the fogging probability is mapped to three levels: low, medium and high, making the evaluation of the fogging situation more precise and accurate.

[0025] Optionally, when the air conditioner is turned off, the defogging strategy corresponding to the low level is:

[0026] Control the air conditioning mode damper to switch to the defrost position to prevent the front windshield from fogging;

[0027] Control the air conditioner's internal and external circulation dampers to switch to the external circulation position;

[0028] Control the air conditioner blower to open a wind stop;

[0029] The air conditioning heating and cooling doors are calculated and determined based on the passenger compartment set temperature;

[0030] The compressor is controlled to be in the off state; since the fogging level is low at this time, there is no need to start the compressor for defogger, and the probability of fogging can be reduced only by ventilation to achieve the purpose of saving energy.

[0031] When the air conditioner is turned on, the defogging strategy corresponding to the low level is:

[0032] Control the air conditioning mode damper to maintain the current position; at this time, the probability of fogging is low, and the air conditioning mode damper is maintained in the current position to ensure the comfort of the passenger compartment while avoiding user perception;

[0033] Control the air conditioner's internal and external circulation damper to switch to the external circulation position; high-humidity air flows out of the passenger compartment and flows into fresh air outside the vehicle;

[0034] Control the air conditioner blower to maintain the current gear; maintain the air conditioner blower at the current gear to achieve the purpose of reducing user perception;

[0035] Control the compressor to maintain the current state; since the fogging level is low at this time, there is no need to start the compressor for defogger to achieve the purpose of saving energy consumption. If the compressor is already working, maintain the current working state; if the compressor is not working, maintain the compressor off state;

[0036] The air conditioning heating and cooling doors are calculated and determined according to the set temperature of the passenger compartment.

[0037] Optionally, when the air conditioner is turned off, the defogging strategy corresponding to the intermediate level is:

[0038] Control the air conditioning mode damper to switch to the defrost position;

[0039] Control the air conditioner's internal and external circulation dampers to switch to the external circulation position;

[0040] Control the air conditioner blower to open the second wind speed;

[0041] The air conditioning heating and cooling doors are calculated and determined based on the passenger compartment set temperature;

[0042] The compressor is controlled to start, and the speed of the compressor is controlled with the surface temperature of the evaporator as the preset temperature as the target; automatic defogger is realized when the air conditioner is turned off; because the fogging level is intermediate at this time, the front windshield may be foggy, so the compressor needs to be started, and the surface temperature of the air conditioner evaporator is lowered to maintain a lower temperature by controlling the speed of the compressor. At this time, when the air entering the passenger compartment flows through the surface of the air conditioner evaporator, due to the low temperature of the evaporator, the moisture in the air condenses on the surface of the air conditioner evaporator to form condensed water which is discharged to the outside of the vehicle through the air conditioner drain pipe, thereby accelerating the reduction of the air humidity in the vehicle and avoiding the formation of obvious fog on the front windshield that affects driving safety.

[0043] When the air conditioner is turned on, the defog strategy corresponding to the intermediate level is:

[0044] Control the air conditioner mode damper to switch to the current position plus defrost mode; for example, if it is currently in face blowing mode, switch to face blowing defrost mode; if it is currently in foot blowing mode, switch to foot blowing defrost mode. While defrosting, the user's current air outlet mode state is retained to achieve the purpose of reducing user perception;

[0045] Control the air conditioner's internal and external circulation dampers to switch to the external circulation position;

[0046] Control the air conditioner blower to perform voltage compensation based on the fogging probability based on the current gear position; the greater the fogging probability, the higher the compensation voltage; but the compensation voltage should not be too high, because the user's current air conditioning blowing mode is retained at this time. If the user is currently in the face blowing mode, suddenly increasing the air volume to blow the face will make the user feel uncomfortable;

[0047] The compressor is controlled to start, and the speed of the compressor is controlled with the evaporator surface temperature as the preset temperature. Since the probability of fogging increases at this time, the surface temperature of the air-conditioning evaporator needs to be lowered by controlling the compressor, and the air humidity is reduced by the low temperature of the evaporator. If the compressor is already working, the compressor is kept in working state. If the compressor is in the off state, the compressor is started, and the speed of the compressor is also controlled according to the preset evaporator surface temperature.

[0048] After entering the automatic defog state, the air conditioning heating and cooling doors are calculated and determined according to the set temperature of the passenger compartment, and when the actual air outlet temperature cannot maintain the set temperature of the passenger compartment, the electric heater is turned on to compensate for the lowered temperature of the air after passing through the surface of the evaporator. Forcibly controlling the surface temperature of the evaporator at the preset temperature will reduce the air outlet temperature of the air conditioner, making the user feel cold. Therefore, after entering the automatic defog state, the air outlet temperature of the air conditioner is still controlled according to the user's set temperature. When the actual air outlet temperature is not enough to maintain the set temperature of the passenger compartment, the electric heater is turned on to heat the air whose temperature has dropped after passing through the surface of the evaporator, so that the temperature of the passenger compartment can maintain the set temperature and ensure the comfort of the passenger compartment.

[0049] Optionally, when the air conditioner is turned off, the advanced corresponding defog strategy is:

[0050] Control the air conditioning mode damper to switch to the defrost position;

[0051] Control the air conditioner's internal and external circulation dampers to switch to the external circulation position;

[0052] Control the air conditioner blower to open the third wind speed; at this time, the probability of fogging is high, and a larger air volume is needed to speed up the air flow and quickly reduce the humidity in the car to avoid obvious fog on the front windshield that affects driving safety;

[0053] The air conditioning heating and cooling doors are calculated and determined based on the passenger compartment set temperature;

[0054] The compressor is controlled to start, and the speed of the compressor is controlled with the evaporator surface temperature as the preset temperature.

[0055] When the air conditioner is turned on, the advanced corresponding defog strategy is:

[0056] Control the air conditioning mode damper to switch to the defrost position;

[0057] Keep the air conditioner blower in the current gear and perform voltage compensation according to the probability of fogging;

[0058] Control the air conditioner's internal and external circulation dampers to switch to the external circulation position;

[0059] Control the compressor to start, and control the compressor speed with the evaporator surface temperature as the preset temperature as the target;

[0060] After entering the automatic defog state, the air conditioning heating and cooling door is calculated and determined according to the set temperature of the passenger compartment, and when the actual air outlet temperature cannot maintain the set temperature of the passenger compartment, the electric heater is turned on to compensate for the lower temperature of the air after passing through the evaporator surface. The electric heater is turned on to compensate for the lower temperature of the air after passing through the evaporator surface to maintain a comfortable temperature in the passenger compartment.

[0061] Optionally, voltage compensation is performed according to the fogging probability, specifically:

[0062] According to the fogging probability, a corresponding relationship table between fogging probability and blower voltage compensation is searched to obtain a blower voltage compensation value;

[0063] The voltage of the air conditioner blower is supplemented based on the blower voltage compensation value. Accurate compensation is achieved through a preset corresponding relationship table, thereby improving driving safety and passenger comfort.

[0064] In a second aspect, an automatic automobile defog control system according to the present invention comprises a memory and a controller, wherein the memory stores a computer-readable program, and when the computer-readable program is called by the controller, the steps of the automatic automobile defog control method according to the present invention can be executed.

[0065] In a third aspect, a car according to the present invention adopts the car automatic defog control system according to the present invention.

[0066] In a fourth aspect, a storage medium according to the present invention stores a computer-readable program therein, and when the computer-readable program is called, the steps of the automatic defog control method for an automobile according to the present invention can be executed.

[0067] Beneficial effects of the present invention:

[0068] (1) The present invention accurately calculates the probability of fogging of the vehicle interior glass by comprehensively considering multiple key environmental factors (including glass temperature, dew point temperature, vehicle interior temperature and vehicle interior humidity). Compared with a single factor, this comprehensive calculation method can more comprehensively reflect the complex process of water vapor condensing into fog on the glass surface in the actual environment, thereby greatly improving the accuracy of the fogging probability calculation.

[0069] (2) The present invention can calculate the probability of fogging even when the air conditioner is not turned on, and turn on the automatic defog function before the front windshield fogs up, so as to avoid the user manually operating the air conditioner after fogging occurs during driving, which affects driving safety. At the same time, when the air conditioner is running, the compressor, electric heater, air conditioner internal and external circulation damper, air conditioner heating and cooling damper, air conditioner mode damper, air conditioner blower, etc. can be controlled to achieve automatic defog while minimizing the impact on the comfort of the passenger compartment.

[0070] In summary, the present invention solves the problem of being unable to prevent fogging in advance due to inaccurate calculation of the fogging probability, the problem of being unable to defog quickly after entering the defog state, and the problem of being unable to prevent fogging and automatically defog when the user has not turned on the air conditioner. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 This is a flow chart of the automatic defog control method for a vehicle in an embodiment of the present application;

[0072] Figure 2 This is a schematic diagram of the automatic defog control method for a vehicle in an embodiment of the present application;

[0073] Figure 3 This is a flow chart of an automatic defog control method for a car in a state where the air conditioner is turned off according to an embodiment of the present application;

[0074] Figure 4This is a flow chart of an automatic defog control method for a car in an air-conditioning-on state according to an embodiment of the present application;

[0075] Figure 5 This is a schematic diagram of the air-conditioning mode damper control principle in the embodiment of the present application;

[0076] Figure 6 This is a principle block diagram of the automobile automatic defog control system in the embodiment of the present application;

[0077] In the figure: 1-interior temperature sensor, 2-exterior temperature sensor, 3-in-vehicle humidity sensor, 4-glass temperature sensor, 5-thermal management controller, 6-compressor, 7-electric heater, 8-air conditioning internal and external circulation damper, 9-air conditioning cooling and heating damper, 10-air conditioning mode damper, 11-air conditioning blower, 12-memory, 13-controller. DETAILED DESCRIPTION

[0078] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0079] like Figure 1 As shown, in an embodiment of the present application, a method for controlling automatic defog of a vehicle comprises the following steps:

[0080] Get the glass temperature, interior temperature, dew point temperature, and interior humidity.

[0081] The first fogging probability is obtained by looking up the first table according to the difference between the glass temperature and the dew point temperature.

[0082] The second fogging probability is obtained by looking up the second table according to the difference between the temperature inside the vehicle and the temperature of the glass.

[0083] The third fogging probability is obtained by looking up the third table according to the humidity inside the vehicle.

[0084] The fogging probability is calculated based on the first fogging probability, the second fogging probability and the third fogging probability.

[0085] The fogging level is determined according to the fogging probability, and defogger is performed based on the defogger strategy corresponding to the fogging level.

[0086] The first table is a table of correspondence between the difference between the glass temperature and the dew point temperature and the first fogging probability. The second table is a table of correspondence between the difference between the interior temperature and the glass temperature and the second fogging probability. The third table is a table of correspondence between the interior humidity and the third fogging probability.

[0087] The first table of a certain car model, see Table 1:

[0088] Glass temperature-dew point temperature (℃) -2 -1 0 1 2 3 5 First fog probability (%) 50 35 25 20 15 5 0

[0089] The second table for a certain car model, see Table 2:

[0090] Interior temperature - glass temperature (℃) -15 -10 -5 0 5 10 15 Second fogging probability (%) -25 -20 -15 -10 0 5 10

[0091] The third table of a certain model, see Table 3:

[0092]

[0093]

[0094] In the embodiment of the present application, the first table, the second table and the third table are obtained by calibrating the actual vehicle in different scenarios.

[0095] In a possible embodiment, the fogging probability is calculated according to the first fogging probability, the second fogging probability and the third fogging probability, specifically as follows:

[0096] Fogging probability = first fogging probability + second fogging probability + third fogging probability.

[0097] Directly adding three different fogging probabilities (ie, the first, second, and third fogging probabilities) to obtain a final fogging probability can ensure the accuracy of the final fogging probability.

[0098] In a possible embodiment, the fogging level includes low, medium and high levels, wherein the fogging level is determined according to the fogging probability, including:

[0099] When it is determined that the fogging probability is greater than the first threshold and less than or equal to the second threshold, the fogging level is determined to be low.

[0100] When it is determined that the fogging probability is greater than the second threshold and less than or equal to the third threshold, the fogging level is determined to be medium.

[0101] When it is determined that the fogging probability is greater than the third threshold, the fogging level is determined to be high.

[0102] Among them, the first threshold value < the second threshold value < the third threshold value. By setting three different threshold values ​​(and there is a clear increasing relationship between the threshold values), the fogging probability is mapped to three levels: low, medium and high, making the evaluation of the fogging situation more precise and accurate.

[0103] In a possible embodiment, the first threshold value is recommended to be 35%, which can be adjusted appropriately according to the needs, such as 32%, 33%, 34%, 36%, 37%, 38%. The second threshold value is recommended to be 50%, which can be adjusted appropriately according to the needs, such as 47%, 48%, 49%, 51%, 52%, 53%. The third threshold value is recommended to be 70%, which can be adjusted appropriately according to the needs, such as 67%, 68%, 69%, 71%, 72%, 73%.

[0104] The following takes the first threshold value of 35%, the second threshold value of 50% and the third threshold value of 70% as an example to illustrate the automatic defog control method for a car when the air conditioner is turned off:

[0105] like Figure 2 , Figure 3 and Figure 5 As shown, the hardware involved includes an interior temperature sensor 1, an exterior temperature sensor 2, an interior humidity sensor 3, a glass temperature sensor 4, a thermal management controller 5, a compressor 6, an air conditioning internal and external circulation damper 8, an air conditioning cold and warm damper 9, an air conditioning mode damper 10 and an air conditioning blower 11, wherein the interior temperature sensor 1, the exterior temperature sensor 2, the interior humidity sensor 3, the glass temperature sensor 4, the compressor 6, the air conditioning internal and external circulation damper 8, the air conditioning cold and warm damper 9, the air conditioning mode damper 10 and the air conditioning blower 11 are respectively connected to the thermal management controller 5. The interior temperature is collected in real time through the interior temperature sensor 1; the exterior temperature is collected in real time through the exterior temperature sensor 2. The interior humidity is collected in real time through the interior humidity sensor 3. The glass temperature of the front windshield is collected in real time through the glass temperature sensor 4. The dew point temperature is calculated by the difference between the interior temperature and the exterior temperature, and the interior humidity. The thermal management controller 5 calculates the fogging probability, and controls the compressor 6, the air conditioner internal and external circulation damper 8, the air conditioner heating and cooling damper 9, the air conditioner mode damper 10, and the air conditioner blower 11 to automatically defog according to the calculation result. The specific steps are as follows:

[0106] Step S1: After the vehicle is powered on, the glass temperature, the interior temperature, the dew point temperature and the interior humidity are obtained, specifically:

[0107] Step S2: The thermal management controller 5 obtains the first fogging probability by looking up the first table according to the difference between the glass temperature and the dew point temperature through the acquired data; obtains the second fogging probability by looking up the second table according to the difference between the temperature inside the vehicle and the temperature of the glass; obtains the third fogging probability by looking up the third table according to the humidity inside the vehicle; and calculates the fogging probability according to the first fogging probability, the second fogging probability and the third fogging probability.

[0108] Step S3: Determine the fogging probability. When the fogging probability satisfies: 35%<F≤50%, determine that the fogging level is low, and enter the defogging strategy corresponding to the low level, where F represents the fogging probability.

[0109] Step S4: Switch the air conditioning mode damper 10 to the defrost position, and control the air conditioning mode damper 10 to blow air toward the front windshield surface, thereby isolating the high-humidity air in the vehicle from the front windshield and preventing obvious fogging on the front windshield.

[0110] Step S5: Switch the air conditioner internal and external circulation damper 8 to the external circulation position. By controlling the air conditioner internal and external circulation damper 8 to switch the air flow to the external circulation, the high-humidity air in the car is blown out of the car, and the introduced fresh air flows through the low-temperature evaporator surface to condense water before entering the car. The flow of dry fresh air and the outflow of moist air in the car accelerate the decrease of the air humidity in the car.

[0111] Step S6: The air conditioning blower 11 is turned on to provide a wind shield.

[0112] Step S7: The air conditioning heating and cooling door 9 is calculated and determined according to the set temperature of the passenger compartment;

[0113] Since the probability of fogging is low at this time, there is no need to start the compressor 6 for defogger, and the fogging probability can be reduced only by ventilation to achieve the purpose of saving energy.

[0114] Step S8: Calculate and determine the fogging probability in real time until the fogging probability drops below 35%, then exit the automatic defog state and return to the air conditioning off state.

[0115] Step S9: When the fogging probability F satisfies: 50%<F≤70%, it is determined that the fogging level is medium, and the defogging strategy corresponding to the medium level is entered.

[0116] Step S10: Switch the air conditioning mode damper 10 to the defrost position or keep the defrost position.

[0117] Step S11: Switch the air conditioner internal and external circulation damper 8 to the external circulation position or keep the external circulation position.

[0118] Step S12: Turn on the second wind speed of the air-conditioning blower 11.

[0119] Step S13: The air conditioning heating and cooling door 9 is calculated and determined according to the set temperature of the passenger compartment.

[0120] Step S14: start the compressor 6, and adjust the speed of the compressor 6 so that the surface temperature of the air conditioner evaporator is a preset temperature (for example, 3°C). Since the probability of fogging is medium at this time, the front windshield may be foggy, so the compressor 6 needs to be started, and the surface temperature of the air conditioner evaporator is lowered to maintain a relatively low temperature by controlling the speed of the compressor 6. At this time, when the air entering the passenger compartment flows through the surface of the air conditioner evaporator, due to the low temperature of the evaporator, the moisture in the air condenses on the surface of the air conditioner evaporator, forming condensed water that is discharged to the outside of the vehicle through the air conditioner drain pipe, accelerating the reduction of the air humidity in the vehicle, and avoiding the formation of obvious fog on the front windshield to affect driving safety.

[0121] Step S15: Calculate and determine the fogging probability in real time. When the fogging probability drops below 50%, exit the defogging strategy corresponding to the intermediate level and return to step S3, that is, return to the defogging strategy corresponding to the low level.

[0122] Step S16: When the fogging probability satisfies: 70%<F, it is determined that the fogging level is high, and the defogging strategy corresponding to the high level is entered.

[0123] Step S17: Switch the air conditioning mode damper 10 to the defrost position or maintain the defrost position.

[0124] Step S18: Switch the air conditioner internal and external circulation damper 8 to the external circulation position or maintain the external circulation position.

[0125] Step S19: Turn on the third wind speed of the air conditioner blower 11. At this time, the probability of fogging is high, and a larger air volume is needed to speed up the air flow and quickly reduce the humidity in the car to avoid obvious fogging on the front windshield that affects driving safety.

[0126] Step S20: The air conditioning heating and cooling door 9 is calculated and determined according to the set temperature of the passenger compartment.

[0127] Step S21: Turn on the compressor 6 or keep the compressor 6 turned on, and control or maintain the surface temperature of the air conditioner evaporator at 3°C.

[0128] Step S22: Calculate the fogging probability in real time. When the fogging probability drops below 70%, exit the defogging strategy corresponding to the advanced level and return to step S9, that is, return to the defogging strategy corresponding to the intermediate level.

[0129] The following describes the automatic defog control method for a car when the air conditioner is turned on by taking the first threshold value as 35%, the second threshold value as 50%, and the third threshold value as 70% as an example:

[0130] like Figure 2 , Figure 4 and Figure 5As shown, the hardware involved includes an interior temperature sensor 1, an exterior temperature sensor 2, an interior humidity sensor 3, a glass temperature sensor 4, a thermal management controller 5, a compressor 6, an electric heater 7, an air conditioner internal and external circulation damper 8, an air conditioner heating and cooling damper 9, an air conditioner mode damper 10, and an air conditioner blower 11; wherein the interior temperature sensor 1, the exterior temperature sensor 2, the interior humidity sensor 3, the glass temperature sensor 4, the compressor 6, the electric heater 7, the air conditioner internal and external circulation damper 8, the air conditioner heating and cooling damper 9, the air conditioner mode damper 10, and the air conditioner blower 11 are respectively connected to the thermal management controller 5. wherein, the thermal management controller 5 calculates the fogging probability through the data collected in real time by the interior temperature sensor 1, the exterior temperature sensor 2, the interior humidity sensor 3, and the glass temperature sensor 4, and controls the compressor 6, the electric heater 7, the air conditioner internal and external circulation damper 8, the air conditioner heating and cooling damper 9, the air conditioner mode damper 10, and the air conditioner blower 11 to automatically defog according to the calculated fogging probability. Entering automatic defog when the air conditioning is on is different from entering automatic defog when the air conditioning is off. When the air conditioning is on, while automatic defog is performed to ensure driving safety, it must also ensure that the comfort of the passenger compartment is not destroyed. It is necessary to minimize the user's perception of the air conditioning entering automatic defog state during use of the air conditioning, thereby reducing the impact on the comfort of the passenger compartment.

[0131] When the air conditioner is on, the specific steps are as follows:

[0132] Step S23: When the calculated fogging probability satisfies: 35%<F≤50%, it is determined that the fogging level is low, and the defogging strategy corresponding to the low level is entered.

[0133] Step S24: At this time, the probability of fogging is low, and the air conditioning mode damper 10 maintains the current position to ensure the comfort of the passenger compartment while avoiding user perception.

[0134] Step S25: Switch the air conditioner internal and external circulation damper 8 to the external circulation position or maintain the external circulation position, so that high-humidity air flows out of the passenger compartment and fresh air flows in.

[0135] Step S26: Maintain the current gear position of the air-conditioning blower 11 to reduce user perception.

[0136] Step S27: The air conditioning heating and cooling door 9 is automatically calculated and determined according to the set temperature of the passenger compartment.

[0137] Step S28: Since the probability of fogging is low at this time, there is no need to start the compressor 6 for defogger to achieve the purpose of saving energy consumption. If the compressor 6 is already working, the current working state is maintained; if the compressor 6 is not working, the compressor 6 is kept off.

[0138] Step S29: Calculate the fogging probability in real time. When the fogging probability drops below 35%, exit the automatic defog state and return to the air conditioner running state before entering the automatic defog state.

[0139] Step S30: If the calculated fogging probability satisfies: 50%<F≤70%, it is determined that the fogging level is medium, and the defogging strategy corresponding to the medium level is entered.

[0140] Step S31: Switch the air conditioner mode damper 10 to the current position plus defrost mode, for example, if it is currently in the face blowing mode, switch to the face blowing defrost mode, if it is currently in the foot blowing mode, switch to the foot blowing defrost mode. While performing defrosting, the user's current air outlet mode state is retained to achieve the purpose of reducing the user's perception.

[0141] Step S32: Switch the air conditioner internal and external circulation damper 8 to the external circulation position or maintain the external circulation position.

[0142] Step S33: The air-conditioning blower 11 performs voltage compensation according to the fogging probability based on the current gear position. The greater the fogging probability, the higher the compensation voltage, see Table 4. However, the compensation voltage should not be too high because the user's current air-conditioning blowing mode is retained at this time. If the user is currently in the face-blowing mode, suddenly increasing the air volume to blow on the face will make the user feel uncomfortable.

[0143] Step 34: Since the probability of fogging increases at this time, it is necessary to lower the surface temperature of the air-conditioning evaporator by controlling the compressor 6, and reduce the air humidity by low temperature of the evaporator. If the compressor 6 is already working, keep the compressor 6 in working state. If the compressor 6 is in the off state, start the compressor 6, and also control the speed of the compressor 6 according to the evaporator surface temperature of 3°C.

[0144] Step 35: At this time, forcibly controlling the surface temperature of the evaporator at 3°C ​​will reduce the air outlet temperature of the air conditioner and make the user feel cold. Therefore, after entering the automatic defog state, the air outlet temperature of the air conditioner is still controlled according to the set temperature of the passenger compartment. When the actual air outlet temperature is not enough to maintain the set temperature of the passenger compartment, the electric heater 7 is turned on to heat the air whose temperature is lowered after flowing through the surface of the evaporator, so that the temperature of the passenger compartment can maintain the set temperature, thereby ensuring the comfort of the passenger compartment.

[0145] Step 36: Calculate the fogging probability in real time. When the fogging probability drops below 50%, return to step S23, that is, return to the defogging strategy corresponding to the low level.

[0146] Step 37: If the calculated fogging probability satisfies: F>70%, the fogging level is determined to be high, and the defogging strategy corresponding to the high level is entered.

[0147] Step 38: Switch the air conditioning mode damper 10 to the defrost position. At this time, the high probability of fogging may quickly form fog on the front windshield, affecting driving safety. Therefore, some comfort will be sacrificed to ensure that there is no large area of ​​obvious fog on the front windshield that affects driving safety.

[0148] Step S39: Keep the air-conditioning blower 11 in the current gear position, but perform voltage compensation according to the fogging probability, see Table 4.

[0149] Step S40: Switch the air conditioner internal and external circulation damper 8 to the external circulation position or maintain the external circulation position.

[0150] Step S41: Start the compressor 6 or keep the compressor 6 turned on, and control the speed of the compressor 6 according to the target temperature of the evaporator surface at 3°C.

[0151] Step S42: Turn on the electric heater 7 to compensate for the lowered temperature of the air after it flows through the evaporator surface, so as to maintain a comfortable temperature in the passenger compartment.

[0152] Step S43: Calculate the current fogging probability F in real time. When the calculated current fogging probability drops below 70%, return to step S30, that is, return to the defogging strategy corresponding to the intermediate level.

[0153] The present invention can effectively intervene in advance to prevent a large area of ​​fog from appearing on the front windshield, and can effectively eliminate the fog on the front windshield in a relatively short time to ensure driving safety.

[0154] In a possible embodiment, voltage compensation is performed according to the fogging probability, specifically as follows:

[0155] According to the fogging probability, the corresponding relationship table between the fogging probability and the blower voltage compensation is looked up to obtain the blower voltage compensation value; based on the blower voltage compensation value, the voltage of the air-conditioning blower 11 is supplemented.

[0156] The corresponding relationship table between the fogging probability and blower voltage compensation of a certain vehicle type (obtained through experimental calibration) is shown in Table 4.

[0157] Fogging probability (%) 50 75 80 90 100 Blower voltage compensation (unit V) 0.0 1.0 1.2 1.6 2.0

[0158] like Figure 6As shown, in the embodiment of the present application, an automobile automatic defog control system includes a memory 12 and a controller 13. The memory 12 stores a computer-readable program. When the computer-readable program is called by the controller 13, the steps of the automobile automatic defog control method in the embodiment of the present application can be executed. After adopting this system, during the user's use, the user's perception of the automatic defog triggering can be reduced as much as possible, and prevention can be triggered before the front windshield is obviously fogged to ensure driving safety. While triggering the automatic defog to ensure safety, the impact on the comfort of the passenger compartment is minimized.

[0159] In an embodiment of the present application, a car adopts the car automatic defog control system as described in the embodiment of the present application.

[0160] In an embodiment of the present application, a storage medium stores a computer-readable program, and when the computer-readable program is called, it can execute the steps of the automatic defog control method for a vehicle as described in the embodiment of the present application.

[0161] In an embodiment of the present application, the storage medium may be a tangible storage medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or equipment. The storage medium may be a machine-readable signal storage medium or a machine-readable storage medium. The storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or equipment, or any suitable combination of the foregoing. A more specific example of a storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0162] The above-mentioned embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above-mentioned embodiments. Any other changes, modifications, substitutions, combinations and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement modes and shall be included in the protection scope of the present invention.

Claims

1. A method for controlling automatic defog of a vehicle, characterized in that: The following steps are involved: Get glass temperature, interior temperature, dew point temperature and interior humidity; According to the difference between the glass temperature and the dew point temperature, the first fogging probability is obtained by looking up the first table; The second fogging probability is obtained by looking up the second table according to the difference between the temperature inside the vehicle and the temperature of the glass; According to the humidity in the car, the third fogging probability is obtained by looking up the third table; Calculating the fogging probability according to the first fogging probability, the second fogging probability and the third fogging probability; Determining a fogging level according to the fogging probability, and performing defogger based on a defogger strategy corresponding to the fogging level; Wherein, the first table is a correspondence table of the difference between the glass temperature and the dew point temperature and the first fogging probability; The second table is a table of corresponding relations between the difference between the temperature inside the vehicle and the temperature of the glass and the second fogging probability; The third table is a correspondence table between the humidity inside the vehicle and the third fogging probability.

2. The method for controlling the automatic defog of a vehicle according to claim 1, characterized in that: The calculation of the fogging probability according to the first fogging probability, the second fogging probability and the third fogging probability is specifically as follows: The fogging probability is equal to the sum of the first fogging probability, the second fogging probability and the third fogging probability.

3. The automatic defog control method for an automobile according to claim 1, characterized in that: The fogging level includes low, medium and high levels, wherein the fogging level is determined according to the fogging probability, including: When it is determined that the fogging probability is greater than a first threshold value and less than or equal to a second threshold value, determining that the fogging level is the low level; When it is determined that the fogging probability is greater than the second threshold and less than or equal to the third threshold, determining that the fogging level is the intermediate level; When it is determined that the fogging probability is greater than a third threshold, determining the fogging level to be the high level; Among them, the first threshold value is less than the second threshold value and less than the third threshold value.

4. The method for controlling the automatic defog of a vehicle according to claim 3, characterized in that: When the air conditioner is turned off, the defogging strategy corresponding to the low level is: Controlling the air conditioning mode damper (10) to switch to the defrost position; Controlling the air conditioner internal and external circulation damper (8) to switch to the external circulation position; Controlling the air conditioner blower (11) to open a wind shield; The air conditioning heating and cooling door (9) is calculated and determined according to the set temperature of the passenger compartment; Controlling the compressor (6) to be in an off state; When the air conditioner is turned on, the defogging strategy corresponding to the low level is: Controlling the air conditioning mode damper (10) to maintain the current position; Controlling the air conditioner internal and external circulation damper (8) to switch to the external circulation position; Controlling the air conditioning blower (11) to maintain the current gear position; Controlling the compressor (6) to maintain the current state; The air conditioning heating and cooling door (9) is calculated and determined according to the set temperature of the passenger compartment.

5. The method for controlling the automatic defog of a vehicle according to claim 3, characterized in that: When the air conditioner is turned off, the defog strategy corresponding to the intermediate level is: Controlling the air conditioning mode damper (10) to switch to the defrost position; Controlling the air conditioner internal and external circulation damper (8) to switch to the external circulation position; Controlling the air conditioner blower (11) to open the second wind speed; The air conditioning heating and cooling door (9) is calculated and determined according to the set temperature of the passenger compartment; Controlling the compressor (6) to start, and controlling the speed of the compressor (6) with the evaporator surface temperature as a preset temperature as a target; When the air conditioner is turned on, the defog strategy corresponding to the intermediate level is: Controlling the air conditioning mode damper (10) to switch to the current position plus defrost mode; Controlling the air conditioner internal and external circulation damper (8) to switch to the external circulation position; Controlling the air conditioning blower (11) to perform voltage compensation based on the current gear position and the probability of fogging; Controlling the compressor (6) to start, and controlling the speed of the compressor (6) with the evaporator surface temperature as a preset temperature as a target; After entering the automatic defog state, the air conditioning heating and cooling door (9) is calculated and determined according to the set temperature of the passenger compartment, and when the actual air outlet temperature cannot maintain the set temperature of the passenger compartment, the electric heater (7) is turned on to compensate for the temperature drop after the air flows through the evaporator surface.

6. The method for controlling the automatic defog of a vehicle according to claim 3, characterized in that: When the air conditioner is turned off, the advanced corresponding defog strategy is: Controlling the air conditioning mode damper (10) to switch to the defrost position; Controlling the air conditioner internal and external circulation damper (8) to switch to the external circulation position; Controlling the air-conditioning blower (11) to open the third wind speed; The air conditioning heating and cooling door (9) is calculated and determined according to the set temperature of the passenger compartment; Controlling the compressor (6) to start, and controlling the speed of the compressor (6) with the evaporator surface temperature as a preset temperature as a target; When the air conditioner is turned on, the advanced corresponding defog strategy is: Controlling the air conditioning mode damper (10) to switch to the defrost position; Keeping the air conditioning blower (11) in the current gear position and performing voltage compensation according to the probability of fogging; Controlling the air conditioner internal and external circulation damper (8) to switch to the external circulation position; Controlling the compressor (6) to start, and controlling the speed of the compressor (6) with the evaporator surface temperature as a preset temperature as a target; After entering the automatic defog state, the air conditioning heating and cooling door (9) is calculated and determined according to the set temperature of the passenger compartment, and when the actual air outlet temperature cannot maintain the set temperature of the passenger compartment, the electric heater (7) is turned on to compensate for the temperature drop after the air flows through the evaporator surface.

7. The method for controlling the automatic defog of a vehicle according to claim 3, characterized in that: Voltage compensation is performed according to the probability of fogging, specifically: According to the fogging probability, a corresponding relationship table between fogging probability and blower voltage compensation is searched to obtain a blower voltage compensation value; The voltage of the air conditioner blower is supplemented based on the blower voltage compensation value.

8. An automatic defog control system for an automobile, characterized in that: The invention comprises a memory (12) and a controller (13), wherein the memory (12) stores a computer-readable program, and when the computer-readable program is called by the controller (13), the steps of the automatic defog control method for an automobile as claimed in any one of claims 1 to 7 can be executed.

9. A car, characterized in that: The automobile automatic defog control system as claimed in claim 8 is adopted.

10. A storage medium, characterized in that: A computer-readable program is stored therein, and when the computer-readable program is called, the steps of the vehicle automatic defog control method as described in any one of claims 1 to 7 can be executed.

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