Automatic defrosting and demisting control method and system for commercial vehicle

Abstract

The invention relates to an automatic defrosting and demisting control method and system for a commercial vehicle. The automatic defrosting and demisting control method comprises the steps that the air conditioner state, the indoor temperature, the indoor humidity and the glass temperature are obtained; according to the air conditioner state, the indoor temperature, the indoor humidity and the glass temperature, the frosting and fogging risk grade is calculated; acquiring outdoor temperature and illumination intensity; according to the outdoor temperature and the illumination intensity, the frosting and fogging risk grade is corrected; and according to the corrected frosting and fogging risk level, the air conditioning system is automatically controlled to defrost and defog. According to the method, the glass fogging risk can be recognized in advance, the automatic defrosting and demisting function is started, and frequent operation of a user on the air conditioner is reduced; glass fogging can be effectively avoided, a good visual field is maintained, and driving safety is guaranteed; and meanwhile, the comfort of drivers and passengers can be considered.

Description

Technical Field

[0001] This invention relates to the field of commercial vehicle technology, and in particular to an automatic defrosting and defogging control method and system for commercial vehicles. Background Technology

[0002] Existing conventional air conditioning systems typically use passive defrosting and defogging. However, conventional air conditioning requires users to frequently operate the air conditioning system, switching between defrosting / defogging and heating, which affects the driver's attention and poses a safety hazard. Manual defrosting and defogging are only performed after the windows have fogged up, by which time the glass has already been frosted and fogged up, affecting visibility.

[0003] Some high-end models have developed automatic defrosting and defogging functions. However, when the ambient temperature is high and the light intensity / rain is strong, the risk to the car windows is higher. The existing automatic defrosting and defogging functions do not take into account the impact of ambient temperature and light intensity on fogging, so the calculated fogging risk level is biased. Currently, when the automatic defrosting and defogging function is activated, it will change the user's set air outlet mode, air volume level, air outlet temperature, etc., affecting the user's comfort. Summary of the Invention

[0004] The purpose of this invention is to provide an automatic defrosting and defogging control method and system for commercial vehicles, so as to solve the technical problems existing in the prior art.

[0005] This invention is achieved through the following technical solution:

[0006] A method for controlling automatic defrosting and defogging of commercial vehicles includes:

[0007] Obtain air conditioning status, indoor temperature, indoor humidity, and glass temperature;

[0008] Calculate the risk level of frost and fogging based on air conditioning status, indoor temperature, indoor humidity, and glass temperature;

[0009] Obtain outdoor temperature and light intensity;

[0010] Adjust the risk level of frost and fog based on outdoor temperature and light intensity;

[0011] Based on the revised risk level of frost and fogging, the air conditioning system is automatically controlled to defrost and defog.

[0012] Furthermore, the process involves acquiring the air conditioner status, indoor temperature, indoor humidity, and glass temperature; and calculating the frost / fog risk level based on these parameters; the calculation formula includes:

[0013] T d =f(T) in ,RH)

[0014] In the formula, Td T is the dew point temperature of the air. in Here, RH represents indoor temperature, and RH represents indoor humidity.

[0015] L fog =T g -T d

[0016] L fog For the risk level of frost and fog, T g This refers to the temperature of the windshield.

[0017] Furthermore, the outdoor temperature and light intensity are obtained; based on the outdoor temperature and light intensity, the frost and fog risk level is corrected; the calculation formula includes:

[0018] L fog =K out-T ×K E ×(T g -T d )

[0019] In the formula, K out-T K is the correction factor for the risk of defrosting and defogging due to outdoor temperature. E This is the correction factor for the impact of light intensity on the risk of defrosting and defogging.

[0020] The risk level is divided into multiple levels, including at least three levels: low, medium, and high; L fog The risk level is low when T1 is greater than or equal to T2; the risk level is low when T2 is less than or equal to L. fog <In the risk level at time T1, L fog <T2 indicates a high risk level;

[0021] The outdoor temperature is divided into multiple intervals, each interval being K. out-T different;

[0022] The light intensity is divided into multiple intervals, each interval K E different.

[0023] Furthermore, the automatic control of the air conditioning system to defrost and defog based on the revised frost and fogging risk level includes:

[0024] When the risk level is low, the air conditioning system remains in its original state.

[0025] Furthermore, the automatic control of the air conditioning system to defrost and defog based on the revised frost and fogging risk level includes:

[0026] When the risk level is medium, determine if it is raining outside. If so, turn on the air conditioner with the internal circulation mode; otherwise, turn on the air conditioner with the external circulation mode.

[0027] It also determines whether the air conditioning heating mode is turned on before the air conditioning cooling mode is turned on. If not, the air conditioning temperature damper opening remains unchanged; if so, the air conditioning temperature damper opening is corrected. The correction value for the air conditioning temperature damper opening is based on the air conditioning unit structure and performance calibration.

[0028] Furthermore, the automatic control of the air conditioning system to defrost and defog based on the revised frost and fogging risk level includes:

[0029] When the risk level is high, determine if it is raining outside. If so, turn on the air conditioner with the internal circulation mode; otherwise, turn on the air conditioner with the external circulation mode.

[0030] And determine whether the air conditioning heating mode was turned on before the air conditioning cooling mode was turned on. If not, the air conditioning temperature damper opening remains unchanged; if so, the air conditioning temperature damper opening is adjusted.

[0031] And open the defrost damper, adjust the air conditioning fan speed setting, and determine L. fog If the temperature is ≤0℃, the air conditioner fan speed setting will remain unchanged after correction; if it is, the highest air conditioner fan speed setting will be turned on. The air conditioner fan speed setting correction value is based on the performance calibration of the air conditioning unit and blower, as well as the separate control of the defrost damper.

[0032] Furthermore, when the risk level is downgraded from high to low, a hysteresis strategy is activated; including:

[0033] L fog When the risk level increases from T2 to T2+△T, the risk level is downgraded from high to medium, but the air conditioning system remains in the state when the risk level is high.

[0034] L fog When the risk level increases from T2+△T to T1, the risk level is medium, and the air conditioning system remains in the state when the risk level is medium.

[0035] L fog When the risk level increases from T1 to T1+△T, the risk level is downgraded from medium to low, and the air conditioning system remains in the state when the risk level is medium.

[0036] L fog When the risk level rises to a value greater than T1 + ΔT, the risk level is low, and the air conditioning system remains in a state where the risk level is low.

[0037] An automatic defrosting and defogging control system for commercial vehicles, comprising the automatic defrosting and defogging control method for commercial vehicles as described in any of the preceding claims, including:

[0038] Indoor temperature sensor, used to obtain indoor temperature;

[0039] Indoor humidity sensor, used to obtain indoor humidity;

[0040] A glass temperature sensor is used to obtain the temperature of the glass.

[0041] Outdoor temperature sensor, used to obtain outdoor temperature;

[0042] A light intensity sensor is used to acquire light intensity.

[0043] Rain gauges are used to measure rainfall.

[0044] The control module is used to calculate the frost and fog risk level based on the air conditioning status, indoor temperature, indoor humidity and glass temperature; correct the frost and fog risk level based on the outdoor temperature and light intensity; and automatically control the air conditioning system to defrost and defog based on the corrected frost and fog risk level.

[0045] The air conditioning system includes an air conditioning unit, a blower, a face / foot blowing damper motor, a defrost damper motor, an internal / external circulation motor, a temperature damper motor, a heater core, and an evaporator core; among which, the defrost damper motor is controlled separately.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] 1. Simple operation: Conventional air conditioners require users to frequently operate the air conditioner, switching between defrosting, defogging, and heating, which affects the driver's attention and poses a safety hazard; this invention can automatically start defrosting and defogging, reducing the frequency of user operation of the air conditioner.

[0048] 2. Active defrosting and defogging: Conventional air conditioners usually perform passive defrosting and defogging, at which point the glass has already frosted and fogged up, affecting visibility; this invention provides predictive defrosting and defogging, avoiding glass frosting and fogging and ensuring driving safety;

[0049] 3. Fast defrosting and defogging: Defrosting and defogging functions are only activated after the glass has frosted and fogged up, making defrosting and defogging difficult and time-consuming; this invention can proactively identify fogging risks, respond quickly, and defrost and defog promptly, ensuring visibility in the driver's cab and improving driving safety.

[0050] 4. Reduced energy consumption: Activating the defrost and defog function after the glass frosts and fogs up requires a lot of energy, resulting in heat loss for the entire vehicle; this invention can prevent glass frosting and fogging with low energy consumption, which is beneficial to the vehicle's range.

[0051] 5. Strong environmental adaptability: This invention can cope with sudden weather changes and sudden increases in humidity inside the vehicle, preventing frost and fogging on the glass;

[0052] 6. High comfort: Conventional air conditioners only vent air through the windshield after defrosting and defogging, which cannot meet the user's cooling and heating needs; this invention maintains the user's airflow mode when defrosting and defogging are activated, taking into account both user comfort and driving safety. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art are briefly introduced below; obviously, the drawings described below are some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0054] Figure 1 This is a flowchart of the method of the present invention;

[0055] Figure 2 This is a system framework diagram of the present invention. Detailed Implementation

[0056] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0057] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0058] like Figure 1-2 As shown, an automatic defrosting and defogging control method for commercial vehicles includes:

[0059] Obtain air conditioning status, indoor temperature, indoor humidity, and glass temperature;

[0060] Calculate the risk level of frost and fogging based on air conditioning status, indoor temperature, indoor humidity, and glass temperature;

[0061] Obtain outdoor temperature and light intensity;

[0062] Adjust the risk level of frost and fog based on outdoor temperature and light intensity;

[0063] Based on the revised risk level of frost and fogging, the air conditioning system is automatically controlled to defrost and defog.

[0064] Furthermore, obtain the air conditioner status, indoor temperature, indoor humidity, and glass temperature; based on the air conditioner status, indoor temperature, indoor humidity, and glass temperature, calculate the risk level of frost and fogging; the calculation formula includes:

[0065] T d =f(T) in ,RH)

[0066] In the formula, T d T is the dew point temperature of the air. in Here, RH represents indoor temperature, and RH represents indoor humidity.

[0067] L fog =T g -T d

[0068] L fog For the risk level of frost and fog, T g This refers to the temperature of the windshield.

[0069] Furthermore, outdoor temperature and light intensity are obtained; based on outdoor temperature and light intensity, the risk level of frost and fog is adjusted; the calculation formula includes:

[0070] L fog =K out-T ×K E ×(T g -T d )

[0071] In the formula, K out-T K is the correction factor for the risk of defrosting and defogging due to outdoor temperature. E This is the correction factor for the impact of light intensity on the risk of defrosting and defogging.

[0072] The risk level is divided into multiple levels, including at least three levels: low, medium, and high; L fog The risk level is low when T1 is greater than or equal to T2; the risk level is low when T2 is less than or equal to L. fog <In the risk level at time T1, L fog <T2 indicates a high risk level;

[0073] The outdoor temperature is divided into multiple intervals, each interval being K. out-T Different; preferably, the outdoor temperature can be divided into four zones, each zone K out-T Can be calibrated and determined;

[0074] The light intensity is divided into multiple intervals, each interval K E Different; preferably, the light intensity can be divided into four intervals, each interval K E It can be calibrated and determined.

[0075] Furthermore, based on the revised frost and fogging risk level, the air conditioning system is automatically controlled to defrost and defog; including:

[0076] When the risk level is low, the air conditioning system remains in its original state. For example, the air conditioning system can be defined as being in the following states when the risk level is low: heating, face blowing mode, internal circulation, fan speed level 3 (example value), and temperature damper opening 50% (example value).

[0077] Furthermore, based on the revised frost and fogging risk level, the air conditioning system is automatically controlled to defrost and defog; including:

[0078] When the risk level is medium, determine if it is raining outside. If so, turn on the air conditioner with the internal circulation mode; otherwise, turn on the air conditioner with the external circulation mode.

[0079] It also determines whether the air conditioning heating mode is turned on before the air conditioning cooling mode is turned on (AC is turned on). If not, the air conditioning temperature damper opening remains unchanged; if so, the air conditioning temperature damper opening is corrected. The correction value for the air conditioning temperature damper opening is determined based on the air conditioning unit structure and performance calibration. Specifically, the correction value for the air conditioning temperature damper opening is determined through bench testing based on the air conditioning unit structure and performance. The AC is turned on to correct the air conditioning temperature damper opening to ensure that the outlet air temperature remains consistent with that before the AC is turned on, thus ensuring the user's temperature comfort.

[0080] Based on the above, here is an example of the air conditioning system's status when the risk level is raised from low to medium: cooling (AC), face blowing mode, internal circulation (rainy conditions) / external circulation (non-rainy conditions), fan speed level 3, and temperature damper opening increased from 50% to 70% (example value).

[0081] Furthermore, based on the revised frost and fogging risk level, the air conditioning system is automatically controlled to defrost and defog; including:

[0082] When the risk level is high, determine if it is raining outside. If so, turn on the air conditioner with the internal circulation mode; otherwise, turn on the air conditioner with the external circulation mode.

[0083] And determine whether the air conditioner heating mode is turned on before the air conditioner cooling mode is turned on. If not, the air conditioner temperature damper opening remains unchanged; if so, the air conditioner temperature damper opening is adjusted. This is consistent with the above and will not be explained further.

[0084] And open the defrost damper, adjust the air conditioning fan speed setting, and determine L. fogIf the temperature is ≤0℃, and no, the corrected air conditioner fan speed setting remains unchanged; if so, the highest air conditioner fan speed setting will be activated. The air conditioner fan speed setting correction value is based on the performance calibration of the air conditioning unit and blower, as well as the separate control of the defrost damper. Specifically, the air conditioner fan speed setting correction value is determined through bench testing based on the performance of the air conditioning unit and blower, and the fan speed setting is corrected to ensure that the airflow is consistent with that before the defrost damper is opened, guaranteeing user comfort. Before automatic defrosting and defogging, is the air conditioner on? When L... fog At ≤0℃, conditions for fogging have been met; adjust the air conditioner fan speed to maximum.

[0085] Based on the above, here are some examples illustrating the air conditioning system's operation when the risk level rises from medium to high: Cooling (AC), defrosting mode, internal circulation (in rainy conditions) / external circulation (in no rainy conditions), fan speed increased from level 3 to level 4 (example value), and temperature damper opening increased from 50% to 70% (example value). When L... fog If the temperature is further reduced to ≤0℃, the conditions for fogging are met, and the airflow is adjusted to the maximum.

[0086] Furthermore, when the risk level is downgraded from high to low, a hysteresis strategy is activated; including:

[0087] L fog When the risk level increases from T2 to T2+△T, the risk level is downgraded from high to medium, but the air conditioning system remains in the state when the risk level is high.

[0088] L fog When the risk level increases from T2+△T to T1, the risk level is medium, and the air conditioning system remains in the state when the risk level is medium.

[0089] L fog When the risk level increases from T1 to T1+△T, the risk level is downgraded from medium to low, and the air conditioning system remains in the state when the risk level is medium.

[0090] L fog When the risk level rises to a value greater than T1 + ΔT, the risk level is low, and the air conditioning system remains in a state where the risk level is low.

[0091] The aforementioned automatic air conditioning system's defrosting and defogging strategy, when activated, risks frequently switching between two states, leading to frequent state switching of the actuators. This not only affects the reliability of the actuators but also impacts user comfort. To avoid this problem, a risk-reducing hysteresis strategy is implemented. When the risk switches from high to low, a hysteresis interval of ΔT is added, during which the actuators maintain their original state.

[0092] An automatic defrosting and defogging control system for commercial vehicles, comprising the automatic defrosting and defogging control method for commercial vehicles as described in any of the above claims, including:

[0093] An indoor temperature sensor is used to acquire the indoor temperature; it is preferably installed on the lower cover plate of the instrument panel.

[0094] An indoor humidity sensor is used to acquire indoor humidity; it is preferably installed on the lower cover plate of the instrument panel.

[0095] A glass temperature sensor is used to obtain the glass temperature; it is preferably installed on the surface of the windshield.

[0096] An outdoor temperature sensor is used to acquire the outdoor temperature; it is preferably located on the front panel.

[0097] A light intensity sensor is used to acquire light intensity; it is preferably installed on the upper surface of the instrument panel.

[0098] A rain sensor is used to obtain rainfall data; it is preferably installed on the surface of the windshield.

[0099] The control module is used to calculate the frost and fog risk level based on the air conditioning status, indoor temperature, indoor humidity and glass temperature; correct the frost and fog risk level based on the outdoor temperature and light intensity; and automatically control the air conditioning system to defrost and defog based on the corrected frost and fog risk level. The control module is preferably located in the instrument panel.

[0100] The air conditioning system includes an air conditioning unit, a blower, motors for the face / feet blowing dampers, a defrost damper motor, motors for internal / external circulation, a temperature damper motor, a heater core, and an evaporator core; the defrost damper motor is controlled independently. The air conditioning unit is preferably located within the instrument panel, integrating various actuators such as the blower, face / feet blowing damper motor, defrost damper motor, internal / external circulation motor, temperature damper motor, heater core, and evaporator core to realize the functions of the air conditioning system. The defrost damper is controlled independently by a defrost damper motor to ensure that the user's current airflow mode is not affected when the automatic defrost and defogging function is activated.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method of automatic defrosting and defogging control for a commercial vehicle, characterized in that, The method comprises the following steps: obtaining the air conditioner state, indoor temperature, indoor humidity and glass temperature; calculating the frost and fog risk level according to the air conditioner state, indoor temperature, indoor humidity and glass temperature; obtaining the outdoor temperature and light intensity; correcting the frost and fog risk level according to the outdoor temperature and light intensity; automatically controlling the air conditioning system defrosting and demisting according to the corrected frost and fog risk level.

2. The commercial vehicle automatic defrosting and defogging control method and system of claim 1, wherein, The method comprises the following steps: obtaining the air conditioner state, indoor temperature, indoor humidity and glass temperature; the calculation formula T d = f(T in , RH) where T d is the dew point temperature for air, T in is the indoor temperature, and RH is the indoor humidity; L fog = T g - T d L fog T g is the front glass temperature.

3. The commercial vehicle automatic defrosting defogging control method and system of claim 2, wherein, The method comprises the following steps: obtaining the outdoor temperature and light intensity; correcting the frost and fog risk level according to the outdoor temperature and light intensity; the calculation formula L fog = K out-T × K E × (T g - T d ) In the formula, K out-T is a correction factor for outdoor temperature on defrosting and demisting risk, K E is a correction factor for light intensity on defrosting and demisting risk; Wherein the risk level is divided into multiple levels, at least including low, medium and high levels; L fog The risk level is low when T1 fog The risk level is medium when T1 fog The risk level is high when T2 dividing the outdoor temperature into a plurality of intervals, each interval K out-T different; The light intensity is divided into multiple intervals, each interval K E Different.

4. The commercial vehicle automatic defrosting and defogging control method and system of claim 3, wherein, The method comprises the following steps: automatically controlling the air conditioning system defrosting and demisting according to the corrected frost and fog risk level; comprising:

5. The commercial vehicle automatic defrosting and defogging control method and system of claim 4, wherein, when the risk level is low, the air conditioning system remains in the original state. The method comprises the following steps: automatically controlling the air conditioning system defrosting and demisting according to the corrected frost and fog risk level; comprising:

6. The commercial vehicle automatic defrosting and defogging control method and system of claim 5, wherein, when the risk level is medium, judging whether it is raining outside, if yes, starting the air conditioning internal circulation; if no, starting the air conditioning external circulation; and judging whether the air conditioning heating mode is started before the air conditioning cooling mode is started, if no, the air conditioning temperature damper opening degree remains unchanged; if yes, correcting the air conditioning temperature damper opening degree; wherein the air conditioning temperature damper opening degree correction value is calibrated according to the air conditioning box structure and performance. The method comprises the following steps: And open the defrost damper, correct the air conditioning air volume position, determine L fog Whether ≤0 ℃, if not, the corrected air conditioning air volume position remains unchanged; if yes, open the highest air conditioning air volume position; wherein the air conditioning air volume position correction value is calibrated according to the air conditioning box and the blower performance, and the defrost damper is independently controlled to open and close.

7. The commercial vehicle automatic defrosting defogging control method and system of claim 6, wherein, automatically controlling the air conditioning system defrosting and demisting according to the corrected frost and fog risk level; comprising: when the risk level is high, judging whether it is raining outside, if yes, starting the air conditioning internal circulation; if no, starting the air conditioning external circulation; L fog When T2 rises to T2+△T, the risk level is downgraded from high to medium, and the air conditioning system remains in the state of the high risk level. L fog When T2+△T rises to T1, the risk level is medium, and the air conditioning system remains in the state of medium risk level; L fog When T1 rises to T1+△T, the risk level is downgraded from medium to low, and the air conditioning system remains in the state when the risk level is medium. L fog When the temperature rises to more than T1+△T, the risk level is low, and the air conditioning system remains in the state of low risk level.

8. A commercial vehicle automatic defrosting and demisting control system comprising the commercial vehicle automatic defrosting and demisting control method according to any one of claims 1 to 7, characterized in that, and judging whether the air conditioning heating mode is started before the air conditioning cooling mode is started, if no, the air conditioning temperature damper opening degree remains unchanged; if yes, correcting the air conditioning temperature damper opening degree; when the risk level is reduced from high to low, starting the hysteresis strategy. The method comprises the following steps: The method comprises the following steps: an indoor temperature sensor for obtaining the indoor temperature; an indoor humidity sensor for obtaining the indoor humidity; a glass temperature sensor for obtaining the glass temperature; an outdoor temperature sensor for obtaining the outdoor temperature; a light intensity sensor for obtaining the light intensity; a rain sensor for obtaining the rainfall; a control module for calculating the frost and fog risk level according to the air conditioner state, indoor temperature, indoor humidity and glass temperature; correcting the frost and fog risk level according to the outdoor temperature and light intensity; automatically controlling the air conditioning system defrosting and demisting according to the corrected frost and fog risk level; an air conditioning system comprising an air conditioning box, a blower, a face and foot blowing damper motor, a defrosting damper motor, an internal and external circulation motor, a temperature damper motor, a heating core and an evaporator core; wherein the defrosting damper motor is controlled separately.

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