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

Abstract

The present application relates to the technical field of automobile defogging, and particularly relates to an automobile automatic defogging control method and system, an automobile and a storage medium, comprising: acquiring glass temperature, indoor temperature, dew point temperature and indoor humidity; obtaining a first fogging probability by looking up a first table according to a difference between the glass temperature and the dew point temperature; obtaining a second fogging probability by looking up a second table according to a difference between the indoor temperature and the glass temperature; obtaining a third fogging probability by looking up a third table according to the indoor humidity; calculating a 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 defogging based on a defogging strategy corresponding to the fogging level. The present application solves the problem that the prior art cannot prevent fogging in advance due to inaccurate determination of the fogging probability.

Description

Technical Field

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

[0002] With the development of new energy vehicles, automatic air-conditioning technology has also been widely popularized. Unlike traditional fuel vehicles that still use manual air-conditioning in large quantities, automatic air-conditioning has now almost become 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 defogger state too early or too late, staying in the defogger state for a long time, and being unable to effectively defog will all lead to a poor user experience, and the appearance of large areas 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 when 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 fogging probability, and to perform an automatic defogger function 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 fogging probability based on 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 to automatically defog, and the blower air volume, air intake damper, and mode damper are voltage compensated according to the calculated probability. The calculation formula for the fogging probability is: F = [H RH +C1-f(T Incar -T ambient )]×C2÷100, where H RH is the humidity value inside the car, measured by the humidity sensor inside 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 difference between the inside and outside temperatures of the vehicle; C1 and C2 are constants calibrated according to the specific vehicle model, with a general typical value of C1 being 45 and a general typical value of C2 being 80; f(T Incar -T ambient) The independent variable is T Incar -T ambient function. However, this method has the following major problems: First, it cannot prevent fogging 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, which cannot effectively reduce the humidity in the vehicle and cannot prevent fogging or effectively defog. Alternatively, when the air conditioner is turned on and in cooling mode, although the compressor is working, 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 fogging cannot be effectively prevented, or the defogger takes a long time after fogging, affecting driving safety. Third, the calculation method only calculates the temperature difference between the inside and outside of the vehicle to calculate the fogging probability, which leads to certain errors. The fogging of a car's windshield is usually caused by the high temperature and humidity of the air inside the car, while the windshield temperature is low. The moisture in the air inside the car will form fog on the cooler windshield. In this calculation method, although the temperature difference between the inside and outside of the car can reflect the temperature difference between the inside and outside temperature of the car to a certain extent, in actual use, the temperature difference between the windshield and the inside of the car corresponding to the temperature difference between the inside and outside temperature of the car in different scenarios will be different, resulting in errors in the calculation of the fogging probability.

[0006] Therefore, it is necessary to develop a new automobile automatic defogging 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 defogger of an automobile, so as to solve the problem in the prior art that inaccurate judgment of fogging probability leads to inability to prevent fogging in advance.

[0008] In a first aspect, a method for controlling automatic defogging of an automobile 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 inside 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 defogging based on a defogging strategy corresponding to the fogging level;

[0015] 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;

[0016] The second table is a table of correspondence between the difference between the vehicle interior temperature and the glass temperature 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 of the fogging probability according to the first fogging probability, the second fogging probability and the third fogging probability is specifically as follows:

[0019] The fogging probability is equal to the sum of the first fogging probability, the second fogging probability and the third fogging probability. Directly adding the three different fogging probabilities (ie the first, second and third fogging probabilities) to obtain the final fogging probability can ensure the accuracy of 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 and less than or equal to a second threshold, determining the fogging level to be 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 the fogging level to be 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] The first threshold < the second threshold < the third threshold. By setting three different thresholds (with a clear increasing relationship between the thresholds), the fog probability is mapped to three levels: low, medium, and high, making the assessment of the fog 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 windshield;

[0029] The air conditioning cooling and heating 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. The probability of fogging can be reduced only through 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 its current position; at this time, the probability of fogging is low, so the air conditioning mode damper is maintained in its current position to ensure cabin comfort while preventing users from noticing.

[0033] Control the air conditioning internal and external circulation damper to switch to the external circulation position; high-humidity air flows out of the passenger compartment and 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 reduce user perception;

[0035] Control the compressor to maintain the current state; since the fog 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 in the 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 cooling and heating doors are calculated and determined based on the passenger compartment set temperature;

[0042] Control the compressor to start, and control the compressor speed with the evaporator surface temperature as the preset temperature as the target; realize automatic defogger when the air conditioner is turned off; because the fogging level is intermediate at this time, there is a possibility of fogging of the front windshield, 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 compressor speed. At this time, when the air entering the passenger compartment flows through the surface of the air conditioner evaporator, due to the low evaporator temperature, the moisture in the air condenses on the surface of the air conditioner evaporator, forming 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 defogging 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 the current mode is face blowing, it will switch to face blowing defrost mode; if the current mode is foot blowing, it will switch to foot blowing defrost mode. While defrosting, the user's current air outlet mode 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] The air conditioner blower is controlled to perform voltage compensation based on the fogging probability at the current gear. The greater the fogging probability, the higher the compensation voltage. However, the compensation voltage should not be too high, because the user's current air conditioning blowing mode is retained. If the user is currently in the face blowing mode, suddenly increasing the air flow to 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 conditioner 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 automatic defog mode, the air conditioning heating and cooling doors are calculated based on the set passenger compartment temperature. If the actual outlet air temperature cannot maintain the set passenger compartment temperature, the electric heater is activated to compensate for the drop in temperature caused by air passing through the evaporator surface. Forcibly controlling the evaporator surface temperature to the preset temperature would lower the air conditioning outlet temperature, making the user feel cold. Therefore, after entering automatic defog mode, the air conditioning outlet temperature is still controlled according to the user's set temperature. If the actual outlet air temperature is insufficient to maintain the set passenger compartment temperature, the electric heater is activated to heat the air cooled by air passing through the evaporator surface, so that the passenger compartment temperature can be maintained at the set temperature, ensuring passenger comfort.

[0049] Optionally, when the air conditioner is turned off, the advanced corresponding defogging 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; the probability of fogging is high at this time, so a larger air volume is needed to speed up air flow and quickly reduce the humidity inside the car to avoid obvious fogging on the front windshield that affects driving safety;

[0053] The air conditioning cooling and heating 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 defogging 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 based on 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;

[0060] After entering the automatic defog mode, the air conditioning heating and cooling door is calculated based on the passenger compartment set temperature. If the actual air outlet temperature cannot maintain the set passenger compartment temperature, the electric heater is activated to compensate for the drop in air temperature after passing through the evaporator surface. The electric heater is activated to compensate for the drop in air temperature after passing through the evaporator surface, maintaining a comfortable temperature in the passenger compartment.

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

[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 blower voltage compensation value is used to supplement the air conditioner blower voltage. Accurate compensation is achieved through a preset correspondence table, thereby improving driving safety and passenger comfort.

[0064] In a second aspect, the application provides an automatic defogging control system for a vehicle, comprising a memory and a controller, wherein the memory stores a computer readable program, and the computer readable program, when invoked by the controller, can execute the steps of the automatic defogging control method for a vehicle as described in the application.

[0065] In a third aspect, the application provides a vehicle, which employs the automatic defogging control system for a vehicle as described in the application.

[0066] In a fourth aspect, the application provides a storage medium, which stores a computer readable program, and the computer readable program, when invoked, can execute the steps of the automatic defogging control method for a vehicle as described in the application.

[0067] Advantages of the application:

[0068] (1) The application can accurately calculate the probability of fogging on the interior glass of a vehicle by comprehensively considering multiple key environmental factors, including the temperature of the glass, the dew point temperature, the temperature inside the vehicle, and the humidity inside the vehicle. This comprehensive calculation method can more comprehensively reflect the complex process of water vapor condensation on the glass surface in the actual environment compared to a single factor, thereby greatly improving the accuracy of the calculation of the fogging probability.

[0069] (2) The application can calculate the fogging probability even when the air conditioner is not turned on, and can turn on the automatic defogging function before the front windshield fogs up, to avoid the user manually operating the air conditioner during driving to affect driving safety after the fog appears. At the same time, the application can control the compressor, electric heater, air conditioner internal and external circulation air door, air conditioner cold and warm air door, air conditioner mode air door, air conditioner blower, etc. to work when the air conditioner is running, to achieve automatic defogging while minimizing the impact on the comfort of the passenger compartment.

[0070] In summary, the application solves the problems of inaccurate calculation of the fogging probability, inability to prevent fogging in advance, inability to quickly defog after entering the defogging state, and inability to prevent fogging and automatically defog when the user does not turn on the air conditioner. BRIEF DESCRIPTION OF DRAWINGS

[0071] Figure 1 The flowchart of the automatic defogging control method for a vehicle in the embodiments of the application;

[0072] Figure 2 The schematic diagram of the automatic defogging control method for a vehicle in the embodiments of the application;

[0073] Figure 3 The flowchart of the automatic defogging control method for a vehicle in the embodiments of the application when the air conditioner is turned off;

[0074] Figure 4This is a flow chart of a method for controlling automatic defogger of a car when the air conditioner is turned on in 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 functional block diagram of an automatic defogger control system for a vehicle according to an embodiment of the present application;

[0077] In the figure: 1-interior temperature sensor, 2-exterior temperature sensor, 3-interior 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 will be able to 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 the purpose of illustrating the present invention and are not intended to limit 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 defogging of an automobile includes 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 defogging is performed based on the defogging strategy corresponding to the fogging level.

[0086] The first table shows the correspondence between the difference between the glass temperature and the dew point temperature and the first fogging probability. The second table shows the correspondence between the difference between the interior temperature and the glass temperature and the second fogging probability. The third table shows the 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 car 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 the three different fogging probabilities (ie, the first, second, and third fogging probabilities) to obtain the 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 determining the fogging level according to the fogging probability includes:

[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] The first threshold < the second threshold < the third threshold. By setting three different thresholds (with a clear increasing relationship between the thresholds), the fog probability is mapped to three levels: low, medium, and high, making the assessment of the fog situation more precise and accurate.

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

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

[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 / external circulation damper 8, an air conditioning heating / cooling damper 9, an air conditioning mode damper 10, and an air conditioning blower 11. The interior temperature sensor 1, exterior temperature sensor 2, interior humidity sensor 3, glass temperature sensor 4, compressor 6, air conditioning internal / external circulation damper 8, air conditioning heating / cooling damper 9, air conditioning mode damper 10, and air conditioning blower 11 are each connected to the thermal management controller 5. The interior temperature sensor 1 collects the interior temperature in real time, while the exterior temperature sensor 2 collects the exterior temperature in real time. The interior humidity sensor 3 collects the interior humidity in real time, and the glass temperature sensor 4 collects the windshield temperature in real time. The dew point temperature is calculated based on the difference between the interior and exterior temperatures and the interior humidity. The thermal management controller 5 calculates the probability of fogging and controls the compressor 6, the air conditioning internal and external circulation damper 8, the air conditioning heating and cooling damper 9, the air conditioning mode damper 10, and the air conditioning blower 11 to automatically defog based on the calculated result. The specific steps are as follows:

[0106] Step S1: After the vehicle is powered on, obtain the glass temperature, interior temperature, dew point temperature, and interior humidity. 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 based on the acquired data; obtains the second fogging probability by looking up the second table according to the difference between the interior temperature and the glass temperature; obtains the third fogging probability by looking up the third table according to the interior humidity; and calculates the fogging probability based on 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 to separate the high-humidity air in the car from the front windshield, thereby preventing obvious fogging on the front windshield.

[0110] Step S5: Switch the air conditioning internal and external circulation damper 8 to the external circulation position. By controlling the air conditioning internal and external circulation damper 8 to switch the air flow to external circulation, the high-humidity air inside the vehicle is blown out of the vehicle. The introduced fresh air flows through the low-temperature evaporator surface, condenses moisture, and then enters the vehicle. The flow of dry fresh air and the outflow of moist air inside the vehicle accelerate the reduction of the humidity in the vehicle.

[0111] Step S6: The air-conditioning blower 11 is turned on to block the wind.

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

[0113] Since the probability of fogging is low at this time, there is no need to start the compressor 6 for defogger. 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 maintain the defrost position.

[0117] Step S11: Switch the air conditioner internal and external circulation damper 8 to the external circulation position or maintain 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 reaches a preset temperature (e.g., 3°C). Since the probability of fogging is moderate at this time, there is a possibility of fogging the front windshield. Therefore, the compressor 6 needs to be started and the speed of the compressor 6 is controlled to lower the surface temperature of the air conditioner evaporator to maintain a low temperature. At this time, when the air entering the passenger compartment flows over the surface of the air conditioner evaporator, due to the low evaporator temperature, 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, thereby accelerating the reduction of the air humidity in the vehicle and preventing the formation of obvious fog on the front windshield that affects 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, the fogging level is determined to be 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 accelerate 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 with the air conditioner turned on, 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 conditioning internal and external circulation damper 8, an air conditioning heating and cooling damper 9, an air conditioning mode damper 10, and an air conditioning blower 11. 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 conditioning internal and external circulation damper 8, the air conditioning heating and cooling damper 9, the air conditioning mode damper 10, and the air conditioning blower 11 are respectively connected to the thermal management controller 5. The thermal management controller 5 calculates the fogging probability based on the real-time data collected by the interior temperature sensor 1, the exterior temperature sensor 2, the interior humidity sensor 3, and the glass temperature sensor 4. Based on the calculated fogging probability, the compressor 6, the electric heater 7, the air conditioning internal and external circulation damper 8, the air conditioning heating and cooling damper 9, the air conditioning mode damper 10, and the air conditioning blower 11 are controlled to automatically defog. 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, 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%, the fogging level is determined to be 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, ensuring 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 from outside the vehicle.

[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 passenger compartment set temperature.

[0137] Step S28: Since the probability of fogging is low at this time, there is no need to start the compressor 6 for demisting 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 in the off state.

[0138] Step S29: Calculate the fogging probability in real time. When the fogging probability drops below 35%, exit the automatic defogger state and return to the air conditioner's running state before entering the automatic defogger 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 the air conditioner is currently in face blowing mode, switch to face blowing defrost mode; if the air conditioner is currently in foot blowing mode, switch to foot blowing defrost mode. While performing defrost, the user's current air outlet mode is retained to minimize user 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 compensated 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 control the compressor 6 to lower the surface temperature of the air conditioner evaporator, and reduce the air humidity by cooling the evaporator at low temperature. 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 lower the air outlet temperature of the air conditioner, making the user feel cold. Therefore, after entering the automatic defogger 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 evaporator surface, 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 at the current gear, 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 evaporator surface temperature of 3°C.

[0151] Step S42: Turn on the electric heater 7 to compensate for the drop in temperature of the air after it passes 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 large-scale fogging of the front windshield, and can effectively eliminate the fogging of 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; and the voltage of the air-conditioning blower 11 is supplemented based on the blower voltage compensation value.

[0156] See Table 4 for the corresponding relationship between fogging probability and blower voltage compensation for a certain vehicle model (obtained through experimental calibration).

[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 an embodiment of the present application, an automatic automobile defogger control system includes a memory 12 and a controller 13. The memory 12 stores a computer-readable program that, when called by the controller 13, executes the steps of the automatic automobile defogger control method of the embodiment of the present application. With this system, the user's perception of the automatic defogger triggering can be minimized during use. Preventive measures can be triggered before fogging of the front windshield occurs to ensure driving safety. Automatic defogger triggering ensures safety while minimizing the impact on passenger cabin comfort.

[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, which, when called, can execute the steps of the automobile automatic defogger control method as described in the embodiment of the present application.

[0161] In an embodiment of the present application, the storage medium can be a tangible storage medium that can contain or store a program for use by an instruction execution system, device or equipment or used in combination with an instruction execution system, device or equipment. The storage medium can be a machine-readable signal storage medium or a machine-readable storage medium. The storage medium can 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 can 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 embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A method for controlling automatic defogging of an automobile, 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 inside 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 defogging based on a defogging strategy corresponding to the fogging level; 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 vehicle interior temperature and the glass temperature 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 defogger of a vehicle according to claim 1, wherein: 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 vehicle automatic defog control method 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 and less than or equal to a second threshold, determining the fogging level to be 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 the fogging level to be 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; 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 defogger of a vehicle according to claim 3, wherein: When the air conditioner is turned off, the low-level corresponding defogging 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 a windshield; The air conditioning cooling and heating door (9) is calculated and determined according to the passenger compartment set temperature; 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 defogger of a vehicle according to claim 3, characterized in that: When the air conditioner is turned off, the intermediate level 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 second wind speed; The air conditioning cooling and heating door (9) is calculated and determined according to the passenger compartment set temperature; 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 defogging 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 fogging probability based on the current gear 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 defogger state, the air conditioning heating and cooling door (9) is calculated and determined according to the passenger compartment set temperature, and when the actual air outlet temperature cannot maintain the passenger compartment set temperature, 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 defogger 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 cooling and heating door (9) is calculated and determined according to the passenger compartment set temperature; 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 defogging strategy is: Controlling the air conditioning mode damper (10) to switch to the defrost position; Keep the air conditioning blower (11) in the current gear position and perform 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 defogger state, the air conditioning heating and cooling door (9) is calculated and determined according to the passenger compartment set temperature, and when the actual air outlet temperature cannot maintain the passenger compartment set temperature, 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 defogger of a vehicle according to claim 3, characterized in that: Voltage compensation is performed according to the fogging probability, 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 defogging 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 vehicle automatic defogger control method as claimed in any one of claims 1 to 7 can be executed.

9. An automobile, characterized in that: The automobile automatic defogger 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 defogger control method as described in any one of claims 1 to 7 can be executed.

Images