Carbon dioxide refrigerant leakage control method and device

Abstract

The invention relates to the technical field of automobile thermal management, and discloses a carbon dioxide refrigerant leakage control method and device. The method detects the CO2 diffusion velocity of the air supply outlet of the air conditioner in real time; when the CO2 diffusion speed is larger than a preset speed threshold value, the CO2 concentration in the vehicle is obtained; if the CO2 concentration in the vehicle is larger than the preset first concentration threshold value within the preset first time interval, the vehicle window is controlled to be opened; if the CO2 concentration in the vehicle is smaller than or equal to a preset first concentration threshold value, switching to an air conditioner external circulation mode; after the vehicle window is opened, if the CO2 concentration in the vehicle is smaller than or equal to a second concentration threshold value within a preset second time interval, the vehicle window is controlled to be closed, and an air conditioner external circulation mode is switched to; and the CO2 concentration and the air conditioner load are used for adjusting the opening degree of an air conditioner internal and external circulation air door in the air conditioner external circulation mode. According to the invention, the response speed and the response precision of refrigerant leakage are improved, energy can be reasonably utilized, and the comfort of a passenger compartment is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile thermal management, and in particular to a method and device for controlling leakage of carbon dioxide refrigerant. Background Art

[0002] At present, most car air conditioners use R134a as refrigerant, and its GWP (global warming potential) is as high as 1430, which does not conform to the environmental protection concept advocated today. In addition, when the ambient temperature is below -10℃, the heating efficiency of R134a drops significantly, and the heat pump function is greatly reduced. Therefore, PTC has to be added as an auxiliary heat source, which increases both the equipment cost and the power consumption. As the country's environmental protection requirements for refrigerants are gradually increasing, CO2, as a non-toxic and non-flammable refrigerant, has an ODP (ozone depletion potential) of 0 and a GWP of 1. Its heating efficiency is significantly higher than that of R134a, R407c, R1234y and other refrigerants, making it an ideal choice to replace traditional refrigerants.

[0003] One of the characteristics of transcritical CO2 heat pump air conditioners is that the pressure difference between the high-pressure side and the low-pressure side is very high. There is a risk of CO2 leakage in the components and pipelines on the high-pressure side. On the one hand, the leakage of refrigerant CO2 causes the pressure in the pipeline to drop rapidly, and the cooling capacity and heating capacity to drop rapidly. The air conditioning function of the vehicle fails, and the comfort of the passenger compartment decreases. On the other hand, the refrigerant CO2 will leak into the passenger compartment through the air duct. According to the Centers for Disease Control and Prevention, the human body will experience dizziness after being exposed to 5% CO2 by volume for 30 minutes or 7% to 10% CO2 by volume for a few minutes. If the volume fraction of CO2 exceeds the acceptable threshold for the human body, it will threaten the life and health of the passengers. Summary of the invention

[0004] The present invention provides a carbon dioxide refrigerant leakage control method and device, which can improve the response speed of refrigerant leakage and reasonably utilize energy.

[0005] In order to solve the above technical problems, the present invention provides a method for controlling leakage of carbon dioxide refrigerant, comprising:

[0006] Real-time detection of CO2 diffusion rate at air outlet of air conditioner;

[0007] When the CO2 diffusion speed is greater than a preset speed threshold, obtaining the CO2 concentration in the vehicle;

[0008] If the CO2 concentration in the vehicle is greater than a preset first concentration threshold within a preset first time interval, the vehicle windows are controlled to open.

[0009] Furthermore, the carbon dioxide refrigerant leakage control method further includes:

[0010] If the CO2 concentration in the vehicle is less than or equal to the preset first concentration threshold, the air conditioning external circulation mode is switched.

[0011] Furthermore, the carbon dioxide refrigerant leakage control method further includes:

[0012] After the window is opened, if the CO2 concentration in the vehicle is less than or equal to the second concentration threshold within a preset second time interval, the window is controlled to close and the air conditioning external circulation mode is switched.

[0013] Furthermore, in the air conditioning external circulation mode, it also includes:

[0014] Real-time detection of the current CO2 concentration in the car;

[0015] Get the current air conditioning load in real time;

[0016] The preset fuzzy control system is used to adjust the opening of the air conditioning internal and external circulation damper according to the current CO2 concentration in the car and the current air conditioning load.

[0017] Furthermore, the preset fuzzy control system is used to adjust the opening of the air conditioner internal and external circulation damper according to the current CO2 concentration in the vehicle and the current air conditioning load, specifically:

[0018] Determine the current CO2 concentration in the vehicle as the first input variable;

[0019] determining the current air conditioning load as a second input variable;

[0020] The opening degree of the air conditioner's internal and external circulation dampers is determined as the output variable;

[0021] respectively setting the fuzzy domain and fuzzy subset of the first input variable and the second input variable;

[0022] The fuzzy rules are determined as follows: the first input variable is positively correlated with the output variable, the second input variable is negatively correlated with the output variable, and the first input variable has a higher priority than the second input variable;

[0023] After determining the parameters of the fuzzy control system, the fuzzy control system is run to adjust the opening of the internal and external circulation dampers of the air conditioner in real time.

[0024] Furthermore, the carbon dioxide refrigerant leakage control method further includes:

[0025] In the air conditioning external circulation mode, if the CO2 concentration in the car is greater than the preset third concentration threshold, the windows are controlled to open.

[0026] Furthermore, the carbon dioxide refrigerant leakage control method further includes:

[0027] In the air conditioning external circulation mode, if the CO2 concentration in the vehicle is less than or equal to the third concentration threshold within a preset third time interval, the opening of the air conditioning internal and external circulation damper is maintained, and the location information of the repair shop is pushed.

[0028] Furthermore, the obtaining of the CO2 concentration in the vehicle is specifically as follows:

[0029] The CO2 concentration in the vehicle is detected using a CO2 sensor installed in the seat cover.

[0030] Furthermore, the carbon dioxide refrigerant leakage control method further includes:

[0031] The first concentration threshold is greater than the third concentration threshold;

[0032] The second concentration threshold is lower than the third concentration threshold.

[0033] Accordingly, the present invention provides a carbon dioxide refrigerant leakage control device, comprising: a speed detection module, a concentration detection module and a control module;

[0034] The speed detection module is used to detect the CO2 diffusion speed of the air outlet of the air conditioner in real time;

[0035] The concentration detection module is used to obtain the CO2 concentration in the vehicle when the CO2 diffusion speed is greater than a preset speed threshold;

[0036] The control module is used to control the vehicle windows to open if the CO2 concentration in the vehicle is greater than a preset first concentration threshold within a preset first time interval.

[0037] Compared with the prior art, the present invention provides a method and device for controlling leakage of carbon dioxide refrigerant, which has the following beneficial effects:

[0038] The present invention controls the vehicle windows and the air conditioner internal and external circulation dampers by detecting the CO2 diffusion rate at the air supply outlet of the air conditioner and the CO2 concentration at the seat, so as to quickly respond to the refrigerant leakage problem, ensure the safety of the occupants, and improve the comfort of the passenger compartment; the present invention also uses a fuzzy control system to adjust the opening of the air conditioner internal and external circulation dampers in combination with the CO2 concentration of the air conditioner temperature, so as to achieve reasonable control of the air conditioner internal and external circulation dampers, save energy, and improve the response accuracy of refrigerant leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic flow chart of an embodiment of a method for controlling leakage of carbon dioxide refrigerant provided by the present invention;

[0040] Figure 2 A schematic diagram of a fuzzy control system provided by the present invention;

[0041] Figure 3 A flow chart of another embodiment of the carbon dioxide refrigerant leakage control method provided by the present invention;

[0042] Figure 4 A schematic structural diagram of an embodiment of a carbon dioxide refrigerant leakage control device provided by the present invention. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] The flowcharts shown in the accompanying drawings are only examples and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may also be decomposed, combined or partially merged, so the actual execution order may change according to actual conditions.

[0045] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0046] Example 1

[0047] See also Figure 1 , is a flow chart of an embodiment of a method for controlling leakage of carbon dioxide refrigerant provided by the present invention, the method comprises steps 101 to 103, each step is specifically as follows:

[0048] Step 101: Real-time detection of the CO2 diffusion rate at the air outlet of the air conditioner;

[0049] Step 102: When the CO2 diffusion speed is greater than a preset speed threshold, obtaining the CO2 concentration in the vehicle;

[0050] Step 103: If the CO2 concentration in the vehicle is greater than the preset first concentration threshold value within the preset first time interval, control the vehicle windows to open.

[0051] Optionally, refrigerant leaks usually occur at vulnerable locations such as refrigeration system pipe connections, elbows less than 90°, and thin walls of heat exchangers. If you choose to place the CO2 gas sensor on the heat exchanger in the car, facing the air outlet, you can use the non-dispersive infrared (NDIR) principle to detect the CO2 in the air and obtain the CO2 concentration. Then, based on the relationship between time and concentration, calculate the real-time CO2 diffusion rate at the air outlet of the air conditioner.

[0052] Optionally, when it is detected that the CO2 diffusion rate at the air-conditioning outlet is greater than a preset speed threshold, it means that the CO2 diffusion rate in the current car is relatively fast, and the CO2 concentration in the car is too high, affecting the riding comfort of the people in the car. Therefore, when the CO2 diffusion rate at the air-conditioning outlet is greater than the preset speed threshold, the CO2 concentration in the car is obtained in time, and the CO2 concentration in the car is used to judge whether the environment in the car threatens the life and health of the passengers.

[0053] Optionally, if it is detected that the CO2 diffusion rate at the air-conditioning outlet is less than or equal to a preset speed threshold, it means that the current CO2 concentration in the car does not exceed the standard, and the CO2 in the car can be adjusted by relying on fresh air from the door gap and CO2 homogenization without changing the air supply method.

[0054] Optionally, compared with the CO2 concentration at the air-conditioning outlet, the CO2 diffusion rate at the air-conditioning outlet is used as a trigger condition for obtaining the CO2 concentration in the vehicle, so as to avoid the situation where the current CO2 concentration in the vehicle is continuously too high due to the instantaneous appearance of a large amount of CO2 at the air-conditioning outlet, thereby improving the accuracy of detection. Therefore, detecting the CO2 diffusion rate at the air-conditioning outlet can reduce the possibility of misjudgment and reduce resource waste. Detecting the CO2 diffusion rate at the air-conditioning outlet can detect refrigerant leaks in a timely manner and improve the response speed of refrigerant leaks.

[0055] Optionally, in order to improve the detection accuracy of the CO2 concentration in the vehicle, a first time interval is set. When the CO2 concentration in the vehicle within the first time interval is greater than the preset first concentration threshold, it is determined that the current CO2 concentration in the vehicle is high and measures to reduce the CO2 concentration need to be taken. By setting the first time interval, the CO2 concentration in the vehicle can be judged more accurately, the probability of misjudgment can be reduced, and resource waste can be reduced.

[0056] Optionally, a first concentration threshold is set. When the CO2 concentration in the car is greater than the first concentration threshold, it is determined that the CO2 concentration in the current car is seriously exceeded. At this time, a reminder is given that the CO2 concentration is seriously exceeded, and the windows are controlled to open, so as to achieve the effect of quickly reducing the CO2 concentration in the car, so that the CO2 concentration in the car reaches the safe breathing range for the passengers.

[0057] Furthermore, in the first embodiment of the present invention, it also includes:

[0058] If the CO2 concentration in the vehicle is less than or equal to the preset first concentration threshold, the air conditioning external circulation mode is switched.

[0059] Optionally, when the real-time detected CO2 diffusion speed at the air outlet of the air conditioner is greater than a preset speed threshold, it is considered that the current CO2 concentration in the car exceeds the standard. At this time, the degree of excess of the CO2 concentration in the car is further analyzed by detecting the CO2 concentration in the car. If the currently acquired CO2 concentration in the car is less than or equal to the preset first concentration threshold, it is considered that the CO2 concentration in the car slightly exceeds the standard. At this time, a reminder of the slight excess of CO2 concentration is issued, and the air conditioner is switched to the air conditioning external circulation mode. The internal and external circulation dampers of the air conditioner are automatically adjusted to maintain the circulation of fresh air and take away the CO2 in the car, so as to reduce the CO2 concentration in the car.

[0060] Optionally, by setting a first concentration threshold, when the CO2 diffusion rate at the air outlet of the air conditioner is greater than a preset speed threshold, the CO2 concentration in the car is divided into two situations: severe excess of CO2 concentration and slight excess of CO2 concentration. Based on the two different situations, the CO2 concentration in the car is reduced by opening the windows or switching the air conditioner to external circulation mode, thereby ensuring the riding comfort of the passengers in the car as much as possible while reducing the CO2 concentration in the car.

[0061] Furthermore, in the first embodiment of the present invention, it also includes:

[0062] After the window is opened, if the CO2 concentration in the vehicle is less than or equal to the second concentration threshold within a preset second time interval, the window is controlled to close and the air conditioning external circulation mode is switched.

[0063] Optionally, after the windows are opened, the CO2 concentration in the car will decrease due to the exchange of air. Therefore, the CO2 concentration in the car is still detected in real time after the windows are opened, and a second concentration threshold is set. If the CO2 concentration in the car is detected to be less than or equal to the second concentration threshold during the process of opening the windows, it is considered that the current cabin is fully ventilated and the CO2 concentration in the car has dropped rapidly. At this time, the CO2 concentration in the car no longer poses a health hazard to the driver and passengers. At this time, the windows are controlled to close, and the air conditioner is switched to the air conditioning external circulation mode. The air conditioning external circulation mode is used to adjust the CO2 concentration in the car, thereby improving the comfort of the passengers. In addition, when the CO2 concentration in the car is greater than the second concentration threshold, it is determined that the CO2 concentration in the car is still very high at this time, and the windows need to be kept open to quickly reduce the CO2 concentration in the car.

[0064] Furthermore, in the first embodiment of the present invention, in the air conditioning external circulation mode, it also includes:

[0065] Real-time detection of the current CO2 concentration in the car;

[0066] Get the current air conditioning load in real time;

[0067] The preset fuzzy control system is used to adjust the opening of the air conditioning internal and external circulation damper according to the current CO2 concentration in the car and the current air conditioning load.

[0068] Optionally, when using the air conditioning external circulation mode to reduce the CO2 concentration in the car, by adjusting the opening of the air conditioning internal and external circulation damper, the effect of reducing the CO2 concentration and saving energy can be improved. Specifically, the opening of the internal and external circulation damper of the automobile air conditioning is not only related to the CO2 concentration, but also affects the opening of the air conditioning internal and external circulation damper as the damper opening changes, which in turn affects the thermal management energy consumption of the entire vehicle. Therefore, when adjusting the opening of the air conditioning internal and external circulation damper, the current CO2 concentration and air conditioning load in the car are obtained in real time, and the CO2 concentration and air conditioning load in the car are used as the control factors of the opening of the air conditioning internal and external circulation damper, which can effectively reduce the energy consumption of the entire vehicle.

[0069] Furthermore, in the first embodiment of the present invention, a preset fuzzy control system is used to adjust the opening of the air conditioning internal and external circulation damper according to the current CO2 concentration in the vehicle and the current air conditioning load, specifically:

[0070] Determine the current CO2 concentration in the vehicle as the first input variable;

[0071] determining the current air conditioning load as a second input variable;

[0072] The opening degree of the air conditioner's internal and external circulation dampers is determined as the output variable;

[0073] respectively setting the fuzzy domain and fuzzy subset of the first input variable and the second input variable;

[0074] The fuzzy rules are determined as follows: the first input variable is positively correlated with the output variable, the second input variable is negatively correlated with the output variable, and the first input variable has a higher priority than the second input variable;

[0075] After determining the parameters of the fuzzy control system, the fuzzy control system is run to adjust the opening of the internal and external circulation dampers of the air conditioner in real time.

[0076] Optionally, since the factors that affect the opening of the air conditioner's internal and external circulation damper include the CO2 concentration in the car and the air conditioning load, the fuzzy control adjustment method can be used to control the internal and external circulation damper of the automobile air conditioner. Specifically, the CO2 concentration in the car and the air conditioning load are used as two input control quantities, and the opening of the air conditioner's internal and external circulation damper is used as the output control quantity, and then a two-input and one-output fuzzy control system is built. The fuzzy rules are set as the CO2 concentration in the car is positively correlated with the opening of the air conditioner's internal and external circulation damper, the air conditioning load is negatively correlated with the opening of the air conditioner's internal and external circulation damper, and the priority of the CO2 concentration in the car is higher than the air conditioning load, so as to achieve the effect that the greater the CO2 concentration in the car, the greater the opening of the air conditioner's internal and external circulation damper; and the greater the air conditioning load, the smaller the opening of the air conditioner's internal and external circulation damper.

[0077] As an example of the first embodiment of the present invention, see Figure 2, is a schematic diagram of the fuzzy control system provided by the present invention. The fuzzy control system is used to determine the opening of the air conditioner internal and external circulation damper. The CO2 concentration in the car (CO2_Cabin) and the air conditioner load (Energyload_Cabin) are used as two input control quantities, and the opening of the air conditioner internal and external circulation damper (FreshAirRat io) is used as the output control quantity. The fuzzy rule adopts the if-then form to control the positive correlation between the CO2 concentration in the car and the opening of the air conditioner internal and external circulation damper, and the air conditioner load is negatively correlated with the opening of the air conditioner internal and external circulation damper. The priority ranking is that the CO2 concentration in the car has a higher priority than the air conditioner load. After completing the selection of the input and output parameters, the membership function and the rules of the fuzzy controller, the control of the opening of the air conditioner internal and external circulation damper can be judged by the input parameters.

[0078] As an example of the first embodiment of the present invention, in a fuzzy control system, the fuzzy domain of the air conditioning load temperature difference (the difference between the outdoor temperature and the target temperature) can be set to [-50, 30], and the corresponding fuzzy subset is {negative big NB (Negative Big), negative medium NM (Negative Medium), negative small NS (Negative Small), zero ZO (Zero), positive small PS (Positive Small), positive medium PM (Positive Medium), positive big PB (Positive Big)}. The fuzzy domain of CO2 concentration is set to [0, 7%], and the corresponding fuzzy subset is {negative big NB (Negative Big), negative medium NM (Negative Medium), negative small NS (Negative Small), zero ZO (Zero), positive small PS (Positive Small), positive medium PM (Positive Medium), positive big PB (Positive Big)}.

[0079] Furthermore, in the first embodiment of the present invention, it also includes:

[0080] In the air conditioning external circulation mode, if the CO2 concentration in the car is greater than the preset third concentration threshold, the windows are controlled to open.

[0081] Optionally, the CO2 concentration in the car can be reduced by using the air conditioning external circulation mode. However, if the leakage of carbon dioxide refrigerant is large, switching to the air conditioning external circulation mode may not effectively reduce the CO2 concentration in the car. Therefore, in the air conditioning external circulation mode, the CO2 concentration in the car still needs to be detected in real time. A third concentration threshold is set. If the CO2 concentration in the car is greater than the preset third concentration threshold, the current CO2 concentration in the car cannot be effectively alleviated by the air conditioning external circulation mode, and the window is controlled to open.

[0082] Furthermore, in the first embodiment of the present invention, it also includes:

[0083] In the air conditioning external circulation mode, if the CO2 concentration in the vehicle is less than or equal to the third concentration threshold within a preset third time interval, the opening of the air conditioning internal and external circulation damper is maintained, and the location information of the repair shop is pushed.

[0084] Optionally, if the CO2 concentration in the vehicle is detected to be less than or equal to the third concentration threshold in the air conditioning external circulation mode, it means that the air conditioning external circulation mode can effectively reduce the CO2 concentration in the vehicle at this time, so the opening of the air conditioning internal and external circulation damper is maintained. In the event of a carbon dioxide refrigerant leak, in order to protect the safety of the occupants of the vehicle, the nearest vehicle maintenance location is pushed to the driver to solve the carbon dioxide refrigerant leakage problem.

[0085] Further, in the first embodiment of the present invention, the acquisition of the CO2 concentration in the vehicle is specifically as follows:

[0086] The CO2 concentration in the vehicle is detected using a CO2 sensor installed in the seat cover.

[0087] Optionally, the air blowing direction of the air supply vent of the air conditioner is usually directly towards the face of the driver or passenger. Therefore, when the carbon dioxide refrigerant leaks, the CO2 concentration around the head and face of the driver and passenger increases rapidly. Therefore, a carbon dioxide gas sensor is built into the seat cover on the headrest side. The leakage of carbon dioxide refrigerant can be detected more accurately, thereby improving the response speed and response accuracy of refrigerant leakage.

[0088] Furthermore, in the first embodiment of the present invention, it also includes:

[0089] The first concentration threshold is greater than the third concentration threshold;

[0090] The second concentration threshold is lower than the third concentration threshold.

[0091] Optionally, according to existing data analysis, the human body will experience dizziness after being exposed to 5% CO2 for 30 minutes or 7% to 10% CO2 for a few minutes, so the volume fraction of 3% is defined as the average short-term breathing level of more than 15 minutes in the free space of the passenger, and 4% is defined as the upper limit of the passenger breathing zone. If the volume fraction of CO2 exceeds the acceptable threshold for the human body, it will threaten the life and health of the passengers. Therefore, in order to improve the accuracy of carbon dioxide refrigerant leakage control, the relationship between the three concentration thresholds can be set to be that the first concentration threshold is greater than the third concentration threshold is greater than the second concentration threshold.

[0092] As an example of the first embodiment of the present invention, see Figure 3, is a flow chart of another embodiment of the carbon dioxide refrigerant leakage control method provided by the present invention. According to existing simulation studies on carbon dioxide refrigerant leakage, at a leakage rate of more than 5g / s, the CO2 volume fraction in the car will exceed the passenger breathing safety zone; at a low CO2 leakage rate of 5g / s, the CO2 volume fraction in the car will not reach the upper limit of the passenger breathing safety zone. Therefore, 5g / s can be set as the preset speed threshold. Based on the fact that different CO2 concentrations will threaten the health and safety of the human body to varying degrees, the first concentration threshold can be set to 4%, the second concentration threshold can be set to 1%, and the third concentration threshold can be set to 3%. Among them, the time interval for each CO2 concentration detection can also be set manually. For example, the first time interval can be set to 3s, the second time interval can be set to 5s, and the third time interval can be set to 10s. Therefore, the control process of carbon dioxide refrigerant leakage is as follows:

[0093] The CO2 concentration is detected by the air outlet CO2 sensor. According to the relationship between concentration and time, the CO2 diffusion rate at the air outlet is determined. If the CO2 diffusion rate at the air outlet is less than 5g / s, the breathing volume fraction can be reduced by relying on the fresh air from the door gap and CO2 homogenization, and no action is required at this time; if the CO2 diffusion rate at the air outlet is greater than 5g / s, the CO2 concentration in the car is detected by the CO2 sensor set on the seat. When the CO2 concentration is greater than 4% and lasts for 3s, it is determined that the CO2 concentration is seriously exceeded. At this time, an alarm for serious CO2 concentration exceeding the standard is issued, and the window is requested to be opened automatically. If the CO2 concentration is less than or equal to 4% at this time, it is determined that the CO2 concentration is slightly exceeded. At this time, an alarm for slightly exceeding the standard is issued, and a request is made to enter the air conditioning external circulation mode and automatically adjust the internal and external circulation dampers. After opening the window, the CO2 concentration is detected in real time. If the CO2 concentration is less than 1% and lasts for 5s, the window is automatically closed, and a request is made to enter the air conditioning external circulation mode and automatically adjust the internal and external circulation dampers; if the CO2 concentration is greater than 1%, the window is kept open. After entering the air conditioning external circulation mode, the CO2 concentration is detected in real time. If the CO2 concentration is less than 3% and lasts for 10 seconds, the internal and external circulation damper opening is maintained and the location of the nearest car repair shop is pushed; otherwise, an alarm is issued if the CO2 concentration exceeds the standard seriously, and a request is made to automatically open the window.

[0094] In summary, the first embodiment of the present invention provides a method for controlling the leakage of carbon dioxide refrigerant. When the carbon dioxide refrigerant leaks, the CO2 leakage rate at the air outlet of the air conditioner and the CO2 concentration in the car are collected, and the CO2 concentration is adjusted by opening the car window or entering the air conditioner external circulation mode, so as to ensure that the CO2 automobile air conditioning system can better avoid the safety hazards in the passenger compartment, effectively improve the response speed and response accuracy of the refrigerant leakage, and ensure the comfort of the passenger compartment. Among them, when entering the air conditioner external circulation mode, a fuzzy control method is adopted, and the CO2 concentration and the air conditioner load are used as input control quantities to realize the reasonable control and adjustment of the opening of the air conditioner internal and external circulation damper, and reasonably use energy.

[0095] Example 2

[0096] See also Figure 4 , is a structural schematic diagram of an embodiment of a carbon dioxide refrigerant leakage control device provided by the present invention, the device includes a speed detection module 201, a concentration detection module 202 and a control module 203;

[0097] The speed detection module 201 is used to detect the CO2 diffusion speed of the air outlet of the air conditioner in real time;

[0098] The concentration detection module 202 is used to obtain the CO2 concentration in the vehicle when the CO2 diffusion speed is greater than a preset speed threshold;

[0099] The control module 203 is used to control the vehicle windows to open if the CO2 concentration in the vehicle is greater than a preset first concentration threshold value within a preset first time interval.

[0100] Furthermore, in the second embodiment of the present invention, it also includes:

[0101] If the CO2 concentration in the vehicle is less than or equal to the preset first concentration threshold, the air conditioning external circulation mode is switched.

[0102] Furthermore, in the second embodiment of the present invention, it also includes:

[0103] After the window is opened, if the CO2 concentration in the vehicle is less than or equal to the second concentration threshold within a preset second time interval, the window is controlled to close and the air conditioning external circulation mode is switched.

[0104] Furthermore, in the second embodiment of the present invention, in the air conditioning external circulation mode, it also includes:

[0105] Real-time detection of the current CO2 concentration in the car;

[0106] Get the current air conditioning load in real time;

[0107] The preset fuzzy control system is used to adjust the opening of the air conditioning internal and external circulation damper according to the current CO2 concentration in the car and the current air conditioning load.

[0108] Furthermore, in the second embodiment of the present invention, a preset fuzzy control system is used to adjust the opening of the air conditioning internal and external circulation damper according to the current CO2 concentration in the vehicle and the current air conditioning load, specifically:

[0109] Determine the current CO2 concentration in the vehicle as the first input variable;

[0110] determining the current air conditioning load as a second input variable;

[0111] The opening degree of the air conditioner's internal and external circulation dampers is determined as the output variable;

[0112] respectively setting the fuzzy domain and fuzzy subset of the first input variable and the second input variable;

[0113] The fuzzy rules are determined as follows: the first input variable is positively correlated with the output variable, the second input variable is negatively correlated with the output variable, and the first input variable has a higher priority than the second input variable;

[0114] After determining the parameters of the fuzzy control system, the fuzzy control system is run to adjust the opening of the internal and external circulation dampers of the air conditioner in real time.

[0115] Furthermore, in the second embodiment of the present invention, the carbon dioxide refrigerant leakage control method further includes:

[0116] In the air conditioning external circulation mode, if the CO2 concentration in the vehicle is greater than the preset third concentration threshold, the windows are controlled to open.

[0117] Furthermore, in the second embodiment of the present invention, the carbon dioxide refrigerant leakage control method further includes:

[0118] In the air conditioning external circulation mode, if the CO2 concentration in the vehicle is less than or equal to the third concentration threshold within a preset third time interval, the opening of the air conditioning internal and external circulation damper is maintained, and the location information of the repair shop is pushed.

[0119] Furthermore, in the second embodiment of the present invention, the CO2 concentration in the vehicle is obtained, specifically:

[0120] The CO2 concentration in the vehicle is detected using a CO2 sensor installed in the seat cover.

[0121] Furthermore, in the second embodiment of the present invention, it also includes:

[0122] The first concentration threshold is greater than the third concentration threshold;

[0123] The second concentration threshold is lower than the third concentration threshold.

[0124] In summary, the second embodiment of the present invention provides a carbon dioxide refrigerant leakage control device, which is based on the organic combination of modules. When the carbon dioxide refrigerant leaks, by collecting the CO2 leakage rate at the air outlet of the air conditioner and the CO2 concentration in the car, the CO2 concentration is adjusted by opening the car window or entering the air conditioner external circulation mode, so as to ensure that the CO2 automobile air conditioning system can better avoid the safety hazards in the passenger compartment, effectively improve the response speed and response accuracy of the refrigerant leakage, and ensure the comfort of the passenger compartment. Among them, when entering the air conditioner external circulation mode, a fuzzy control method is adopted, and the CO2 concentration and the air conditioning load are used as the input control quantity to realize the reasonable control and adjustment of the opening of the air conditioner internal and external circulation damper, and reasonably use energy.

[0125] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. It is particularly pointed out that for those skilled in the art, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for controlling leakage of carbon dioxide refrigerant, characterized in that: include: Real-time detection of CO2 diffusion rate at air outlet of air conditioner; When the CO2 diffusion speed is greater than a preset speed threshold, obtaining the CO2 concentration in the vehicle; If the CO2 concentration in the vehicle is greater than a preset first concentration threshold within a preset first time interval, the vehicle windows are controlled to open.

2. The method for controlling leakage of carbon dioxide refrigerant according to claim 1, characterized in that: Also includes: If the CO2 concentration in the vehicle is less than or equal to the preset first concentration threshold, the air conditioning external circulation mode is switched.

3. The method for controlling leakage of carbon dioxide refrigerant according to claim 1, characterized in that: Also includes: After the window is opened, if the CO2 concentration in the vehicle is less than or equal to the second concentration threshold within a preset second time interval, the window is controlled to close and the air conditioning external circulation mode is switched.

4. The method for controlling leakage of carbon dioxide refrigerant according to claim 2 or 3, characterized in that: In the air conditioning external circulation mode, it also includes: Real-time detection of the current CO2 concentration in the car; Get the current air conditioning load in real time; The preset fuzzy control system is used to adjust the opening of the air conditioning internal and external circulation damper according to the current CO2 concentration in the car and the current air conditioning load.

5. The method for controlling leakage of carbon dioxide refrigerant according to claim 4, characterized in that: The preset fuzzy control system is used to adjust the opening of the air conditioner internal and external circulation damper according to the current CO2 concentration in the vehicle and the current air conditioning load, specifically: Determine the current CO2 concentration in the vehicle as the first input variable; determining the current air conditioning load as a second input variable; The opening degree of the air conditioner's internal and external circulation dampers is determined as the output variable; respectively setting the fuzzy domain and fuzzy subset of the first input variable and the second input variable; The fuzzy rules are determined as follows: the first input variable is positively correlated with the output variable, the second input variable is negatively correlated with the output variable, and the first input variable has a higher priority than the second input variable; After determining the parameters of the fuzzy control system, the fuzzy control system is run to adjust the opening of the internal and external circulation dampers of the air conditioner in real time.

6. The method for controlling leakage of carbon dioxide refrigerant according to any one of claims 1 to 5, characterized in that: Also includes: In the air conditioning external circulation mode, if the CO2 concentration in the car is greater than the preset third concentration threshold, the windows are controlled to open.

7. The method for controlling leakage of carbon dioxide refrigerant according to any one of claims 1 to 5, characterized in that: Also includes: In the air conditioning external circulation mode, if the CO2 concentration in the vehicle is less than or equal to the third concentration threshold within a preset third time interval, the opening of the air conditioning internal and external circulation damper is maintained, and the location information of the repair shop is pushed.

8. The method for controlling leakage of carbon dioxide refrigerant according to claim 1, characterized in that: The obtaining of the CO2 concentration in the vehicle is specifically as follows: The CO2 concentration in the vehicle is detected using a CO2 sensor installed in the seat cover.

9. The method for controlling leakage of carbon dioxide refrigerant according to claim 1, characterized in that: Also includes: The first concentration threshold is greater than the third concentration threshold; The second concentration threshold is lower than the third concentration threshold.

10. A carbon dioxide refrigerant leakage control device, characterized in that: include: Speed ​​detection module, concentration detection module and control module; The speed detection module is used to detect the CO2 diffusion speed of the air outlet of the air conditioner in real time; The concentration detection module is used to obtain the CO2 concentration in the vehicle when the CO2 diffusion speed is greater than a preset speed threshold; The control module is used to control the vehicle windows to open if the CO2 concentration in the vehicle is greater than a preset first concentration threshold within a preset first time interval.

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