Refrigerant detection method, device, equipment and storage medium

Abstract

The present invention belongs to the field of vehicle detection technology, and discloses a refrigerant detection method, device, equipment and storage medium. This application obtains the ambient temperature and the vehicle air-conditioning pressure if it is detected that the vehicle is started from a cold start; searches for the static air-conditioning pressure threshold corresponding to the ambient temperature; determines the static pressure interval based on the error value and the static air-conditioning pressure threshold; compares the vehicle air-conditioning pressure with the static pressure interval to determine whether the refrigerant is sufficient. Since the static air-conditioning pressure threshold corresponding to the calibrated lower limit of the refrigerant amount at the ambient temperature is found through the ambient temperature, the vehicle air-conditioning pressure is compared with the calibrated static air-conditioning pressure threshold, and in the comparison process, the influence of the sensor or the temperature in the cabin is also taken into account, ensuring that the refrigerant of the vehicle air-conditioning can be accurately detected, thereby realizing the refrigerant detection of the vehicle air-conditioning in the vehicle.

Description

Technical Field

[0001] The present invention relates to the field of vehicle detection technology, and in particular to a refrigerant detection method, device, equipment and storage medium. Background Art

[0002] Refrigerant leakage is a major malfunction in passenger car air conditioners. Abnormal leakage from any component or joint can result in insufficient refrigerant. Even if the refrigerant ducts meet design requirements for airtightness, cumulative leakage can lead to insufficient refrigerant after the vehicle has reached a certain age. When the refrigerant level in a car air conditioner drops below a certain level, its cooling capacity decreases significantly, affecting the air conditioning effect. Furthermore, reduced system flow deteriorates compressor lubrication and cooling, increasing compressor intake and exhaust temperatures and impacting the compressor's lifespan.

[0003] However, the complexity and rapidity of vehicle air conditioning operating conditions far exceed those of household air conditioners. Condenser load, in-vehicle heat load, and compressor speed (especially for belt-driven compressors) all fluctuate dramatically with the external environment, vehicle speed, and engine speed. This results in significantly lower operating stability for automotive air conditioners than for household air conditioners. Furthermore, due to cost and technical limitations, vehicle air conditioners also face numerous hardware restrictions. For example, passenger car air conditioners generally lack inlet and exhaust temperature sensors, and compressor power measurement is difficult. These limitations preclude the ability to directly monitor refrigerant levels in vehicle air conditioners using the same methods used for household air conditioners, resulting in the current lack of refrigerant shortage detection and reminder functions in the passenger car market. Summary of the Invention

[0004] The main purpose of the present invention is to provide a refrigerant detection method, device, equipment and storage medium, aiming to solve the technical problem that the existing technology cannot detect whether there is sufficient refrigerant in the vehicle air conditioner.

[0005] To achieve the above object, the present invention provides a refrigerant detection method, which comprises the following steps:

[0006] If a cold start of the vehicle is detected, the ambient temperature and the vehicle air conditioning pressure are obtained;

[0007] Finding a static air conditioning pressure threshold corresponding to the ambient temperature, where the static air conditioning pressure threshold is a static air conditioning pressure value corresponding to a lower limit of the refrigerant quantity, where the lower limit of the refrigerant quantity is a minimum value of the refrigerant quantity required to maintain normal operation of the vehicle air conditioner;

[0008] determining a static pressure range according to an error value and the static air conditioning pressure threshold, wherein the error value is determined according to a sensor tolerance and / or a vehicle cabin heat impact;

[0009] The vehicle air conditioning pressure is compared with the static pressure range to determine whether the refrigerant is sufficient.

[0010] Optionally, comparing the vehicle air conditioner pressure with the static pressure range to determine whether the refrigerant is sufficient includes:

[0011] If the vehicle air-conditioning pressure is less than the lower limit of the static pressure range, it is determined that the refrigerant is sufficient;

[0012] If the vehicle air-conditioning pressure is greater than the upper limit of the static pressure range, it is determined that the refrigerant is insufficient;

[0013] If the vehicle air-conditioning pressure is within the static pressure range, a refrigerant test is performed to determine whether the refrigerant is sufficient.

[0014] Optionally, if the vehicle air-conditioning pressure is within the static pressure range, performing a refrigerant test to determine whether the refrigerant is sufficient includes:

[0015] If the vehicle air-conditioning pressure is within the static pressure range, controlling the vehicle to enter a refrigerant test state;

[0016] When the vehicle maintains the refrigerant test state and the running time reaches a preset test time threshold, the current ambient temperature, the current vehicle interior temperature, the current heat exchanger temperature and the current air conditioning pressure are obtained;

[0017] Find the air conditioning pressure threshold and temperature difference threshold corresponding to the current ambient temperature;

[0018] determining a current temperature difference according to the current vehicle interior temperature and the current heat exchanger temperature;

[0019] The current air-conditioning pressure is compared with the air-conditioning pressure threshold, and the current temperature difference is compared with the temperature difference threshold, and whether the refrigerant is sufficient is determined according to the comparison results.

[0020] Optionally, if the vehicle air-conditioning pressure is within the static pressure range, controlling the vehicle to enter a refrigerant test state includes:

[0021] If the vehicle air-conditioning pressure is within the static pressure range, the vehicle is controlled to idle, and the vehicle air-conditioning is controlled to operate in a full-cooling internal circulation mode.

[0022] Optionally, if the vehicle air conditioner pressure is within the static pressure range, controlling the vehicle to idle, and controlling the vehicle air conditioner to operate in a full-cooling internal circulation mode with blowing air, includes:

[0023] If the vehicle air-conditioning pressure is within the static pressure range, the vehicle is controlled to idle, and the vehicle air-conditioning is operated in a full-cooling internal circulation mode according to a preset gear;

[0024] The step of searching for the air-conditioning pressure threshold and the temperature difference threshold corresponding to the current ambient temperature includes:

[0025] The air conditioning pressure threshold and the temperature difference threshold corresponding to the current ambient temperature and the preset gear position are searched.

[0026] Optionally, comparing the current air-conditioning pressure with the air-conditioning pressure threshold, and comparing the current temperature difference with the temperature difference threshold, and determining whether the refrigerant is sufficient according to the comparison results includes:

[0027] Comparing the current air-conditioning pressure with the air-conditioning pressure threshold, and comparing the current temperature difference with the temperature difference threshold;

[0028] If the current air-conditioning pressure is less than the air-conditioning pressure threshold, and the current temperature difference is less than the temperature difference threshold, it is determined that the refrigerant is insufficient;

[0029] If the current air-conditioning pressure is greater than or equal to the air-conditioning pressure threshold, or the current temperature difference is greater than or equal to the temperature difference threshold, it is determined that the refrigerant is sufficient.

[0030] Optionally, if a cold start of the vehicle is detected, before obtaining the ambient temperature and the vehicle air conditioning pressure, the method further includes:

[0031] If the vehicle is detected to be started, the ambient temperature and the cooling water temperature are obtained, where the cooling water temperature is the vehicle engine coolant temperature;

[0032] If the difference between the ambient temperature and the cooling water temperature is less than or equal to a preset threshold, it is determined that a vehicle cold start is detected.

[0033] In addition, to achieve the above-mentioned purpose, the present invention further provides a refrigerant detection device, the refrigerant detection device comprising:

[0034] An acquisition module is used to obtain the ambient temperature and the vehicle air conditioning pressure if a cold start of the vehicle is detected;

[0035] a search module, configured to search for a static air-conditioning pressure threshold corresponding to the ambient temperature, wherein the static air-conditioning pressure threshold is a static air-conditioning pressure value corresponding to a lower limit of a refrigerant quantity, wherein the lower limit of a refrigerant quantity is a minimum value of a refrigerant quantity required to maintain normal operation of the vehicle air-conditioning;

[0036] a determination module, configured to determine a static pressure interval according to an error value and the static air conditioning pressure threshold, wherein the error value is determined according to a sensor tolerance and / or a vehicle cabin heat impact;

[0037] The determination module is used to compare the vehicle air-conditioning pressure with the static pressure range to determine whether the refrigerant is sufficient.

[0038] In addition, to achieve the above-mentioned purpose, the present invention also proposes a refrigerant detection device, which includes: a processor, a memory, and a refrigerant detection program stored in the memory and runnable on the processor. When the refrigerant detection program is executed by the processor, the steps of the refrigerant detection method described above are implemented.

[0039] In addition, to achieve the above-mentioned purpose, the present invention further proposes a computer-readable storage medium, on which a refrigerant detection program is stored. When the refrigerant detection program is executed, the steps of the refrigerant detection method described above are implemented.

[0040] The present invention detects the ambient temperature and onboard air conditioning pressure when a cold start of the vehicle is detected; searches for a static air conditioning pressure threshold corresponding to the ambient temperature; determines a static pressure interval based on an error value and the static air conditioning pressure threshold; and compares the onboard air conditioning pressure with the static pressure interval to determine whether refrigerant is sufficient. Because the static air conditioning pressure threshold corresponding to the calibrated lower limit of refrigerant volume at the ambient temperature is found by searching for the ambient temperature, the onboard air conditioning pressure is compared with the calibrated static air conditioning pressure threshold, and the influence of the sensor or cabin temperature is also taken into account during the comparison process, ensuring accurate detection of refrigerant sufficiency in the onboard air conditioning, thereby achieving refrigerant detection of the onboard air conditioning in the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of the structure of an electronic device in the hardware operating environment involved in the embodiment of the present invention;

[0042] Figure 2 This is a schematic flow chart of a first embodiment of a refrigerant detection method according to the present invention;

[0043] Figure 3 This is a flow chart of a second embodiment of the refrigerant detection method of the present invention;

[0044] Figure 4 This is a structural block diagram of the first embodiment of the refrigerant detection device of the present invention.

[0045] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0046] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0047] Reference Figure 1 , Figure 1 This is a schematic diagram of the structure of the refrigerant detection equipment in the hardware operating environment involved in the embodiment of the present invention.

[0048] like Figure 1 As shown, the electronic device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Among them, the communication bus 1002 is used to realize the connection and communication between these components. The user interface 1003 may include a display screen (Display), an input unit such as a keyboard (Keyboard), and the user interface 1003 may optionally include a standard wired interface and a wireless interface. The network interface 1004 may optionally include a standard wired interface and a wireless interface (such as a wireless fidelity (Wireless-Fidelity, WI-FI) interface). The memory 1005 may be a high-speed random access memory (Random Access Memory, RAM) or a stable non-volatile memory (Non-Volatile Memory, NVM), such as a disk storage. The memory 1005 may optionally be a storage device independent of the aforementioned processor 1001.

[0049] Those skilled in the art will understand that Figure 1 The structure shown in the figure does not constitute a limitation to the electronic device, and may include more or fewer components than shown in the figure, or combine certain components, or arrange the components differently.

[0050] like Figure 1 As shown, the memory 1005 as a storage medium may include an operating system, a network communication module, a user interface module, and a refrigerant detection program.

[0051] exist Figure 1 In the electronic device shown, the network interface 1004 is mainly used for data communication with the network server; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 in the electronic device of the present invention can be set in the refrigerant detection device, and the electronic device calls the refrigerant detection program stored in the memory 1005 through the processor 1001, and executes the refrigerant detection method provided by the embodiment of the present invention.

[0052] The embodiment of the present invention provides a refrigerant detection method, referring to Figure 2 , Figure 2Schematic diagram of a flow chart of a first embodiment of a refrigerant detection method according to the present invention.

[0053] In this embodiment, the refrigerant detection method includes the following steps:

[0054] Step S10: If a cold start of the vehicle is detected, the ambient temperature and the vehicle air-conditioning pressure are obtained.

[0055] It should be noted that the executor of this embodiment can be the vehicle itself or a refrigerant detection device installed in the vehicle. The refrigerant detection device can be a controller in the vehicle, such as an ECU controller, or other equipment that can control various components in the vehicle and collect data. This embodiment does not control this. In this embodiment and the following embodiments, the refrigerant detection method of the present invention is described using the refrigerant detection device as an example.

[0056] It should be noted that a cold start can be detected when the vehicle is detected to have been started after being unused for a long period of time. The ambient temperature can be the temperature of the vehicle's environment, which can be collected by an ambient temperature sensor installed in the vehicle. The onboard air conditioning pressure can be the air conditioning pressure when the vehicle's onboard air conditioning is currently running, which can be collected by a pressure sensor (Pd sensor) installed inside the vehicle air conditioning.

[0057] Among them, since the refrigerant quantity of the vehicle air conditioner is detected, it is necessary to perform the detection when the vehicle air conditioner is turned on. Therefore, when it is detected that the vehicle is started from a cold state, it is also possible to detect whether the vehicle air conditioner is started. Only when it is detected that the vehicle is started from a cold state and the vehicle air conditioner is turned on, the ambient temperature and the vehicle air conditioner pressure are obtained, and subsequent steps are executed.

[0058] Step S20: Finding a static air-conditioning pressure threshold corresponding to the ambient temperature.

[0059] It should be noted that the static air-conditioning pressure threshold can be the static air-conditioning pressure value corresponding to the lower limit value of the refrigerant quantity. The lower limit value of the refrigerant quantity is the minimum value of the refrigerant quantity required to maintain the normal operation of the vehicle air-conditioning, that is, the minimum value of the refrigerant quantity that does not affect the operation of the vehicle air-conditioning.

[0060] In actual use, the vehicle manufacturer or the manager of the refrigerant detection equipment can pre-calibrate the vehicle to determine the static air-conditioning pressure threshold of the vehicle's onboard air-conditioning at different ambient temperatures (that is, the air-conditioning pressure value when the onboard air-conditioning maintains stable operation when the refrigerant amount in the vehicle is maintained at the lower limit of the refrigerant amount), and store the calibrated data through the first calibration data table. At this time, searching for the static air-conditioning pressure threshold corresponding to the ambient temperature can be searching for the static air-conditioning pressure threshold corresponding to the ambient temperature in the first calibration data table.

[0061] Step S30: determining a static pressure range according to the error value and the static air-conditioning pressure threshold.

[0062] It should be noted that the error value may be calibrated in advance by the vehicle manufacturer or the manager of the refrigerant detection equipment according to the sensor tolerance and / or the heat impact of the vehicle cabin.

[0063] In actual use, since the sensors used may have certain deviations, and the heat in the vehicle cabin may be different from the actual working conditions of the user, the calibrated static air-conditioning pressure threshold may have certain deviations. Directly using it as a specific judgment threshold may lead to inaccurate judgment. In order to avoid such inaccurate judgment, the impact of the deviation needs to be considered. At this time, the static pressure range can be determined based on the error value and the static air-conditioning pressure threshold.

[0064] Among them, determining the static pressure interval according to the error value and the static air conditioning pressure threshold can be to correct the static air conditioning pressure threshold according to the error value, determine the interval upper limit value and the interval lower limit value, and then determine a static pressure interval according to the interval upper limit value and the interval lower limit value.

[0065] For example: assuming that the static air conditioning pressure threshold is Pd_lwr_limit and the error value is α, the lower limit of the interval is Pd_lwr_limit1 = (1-α)*Pd_lwr_limit, and the upper limit of the interval is Pd_lwr_limit2 = (1+α)*Pd_lwr_limit, then the static pressure interval is [Pd_lwr_limit1, Pd_lwr_limit2].

[0066] Step S40: Compare the vehicle air-conditioning pressure with the static pressure range to determine whether the refrigerant is sufficient.

[0067] It should be noted that under the same working conditions, the more refrigerant there is, the higher the air-conditioning pressure will be. Therefore, by comparing the vehicle air-conditioning pressure with the static pressure range, the current refrigerant amount of the vehicle air-conditioning in the vehicle and the lower limit of the refrigerant amount can be used to determine whether the refrigerant is sufficient.

[0068] In actual use, if the vehicle air conditioning pressure is less than the lower limit of the static pressure interval, it means that the air conditioning pressure of the vehicle air conditioning is less than the minimum value of the interval generated by eliminating the deviation. In this case, it can be directly determined that the refrigerant is insufficient;

[0069] If the vehicle air conditioning pressure is greater than the upper limit of the static pressure interval, it means that the vehicle air conditioning pressure is greater than the maximum value of the interval generated by eliminating the deviation, and it can be directly determined that the refrigerant is sufficient;

[0070] However, if the vehicle air conditioning pressure is in the static pressure range, it is difficult to determine whether the refrigerant is sufficient due to the deviation. In order to ensure that the refrigerant is sufficient, further processing can be performed. In this case, step S40 in this embodiment may include:

[0071] Step S40 ′: If the vehicle air-conditioning pressure is within the static pressure range, a refrigerant test is performed to determine whether the refrigerant is sufficient.

[0072] It should be noted that the refrigerant test can be to control the vehicle to operate under specific working conditions and collect data during operation, and further determine whether the refrigerant is sufficient based on the collected data.

[0073] In a specific implementation, in order to accurately determine whether the vehicle is cold started, before step S10 in this embodiment, the following steps may be further included:

[0074] If the vehicle is detected to be started, the ambient temperature and cooling water temperature are obtained;

[0075] If the difference between the ambient temperature and the cooling water temperature is less than or equal to a preset threshold, it is determined that a vehicle cold start is detected.

[0076] It should be noted that the cooling water temperature may be the vehicle engine coolant temperature. The preset threshold value may be pre-calibrated by the manager of the refrigerant detection equipment or the vehicle manufacturer.

[0077] In actual use, the judgment is made by recording the vehicle's starting status or starting time. However, due to the influence of environmental differences, it is actually difficult to calibrate the time interval between two vehicle starts to determine whether it is a cold start. In this application, the purpose of judging whether the vehicle is a cold start is to eliminate the influence of engine temperature on the vehicle air conditioner. Therefore, the cooling water temperature can be used to determine whether the vehicle is a cold start.

[0078] In actual use, if the difference between the ambient temperature and the cooling water temperature is less than or equal to the preset threshold, it means that the engine coolant temperature in the vehicle is close to the ambient temperature. It can be judged that the vehicle has not been started for a long time. The vehicle's engine will not have a major impact on the on-board air conditioner. Therefore, it can be determined that the vehicle is detected to be started from a cold state.

[0079] This embodiment detects the presence of refrigerant by obtaining the ambient temperature and onboard air conditioning pressure upon detecting a cold start of the vehicle; searching for a static air conditioning pressure threshold corresponding to the ambient temperature; determining a static pressure interval based on an error value and the static air conditioning pressure threshold; and comparing the onboard air conditioning pressure with the static pressure interval to determine whether refrigerant is sufficient. Because the static air conditioning pressure threshold corresponding to the calibrated lower limit of refrigerant volume at that ambient temperature is found by searching for the ambient temperature, the onboard air conditioning pressure is compared with the calibrated static air conditioning pressure threshold, and the effects of the sensor or cabin temperature are taken into account during the comparison process, ensuring accurate detection of refrigerant sufficiency in the onboard air conditioning, thereby achieving refrigerant detection for the vehicle's onboard air conditioning.

[0080] refer to Figure 3 , Figure 3 Schematic diagram of a flow chart of a second embodiment of a refrigerant detection method according to the present invention.

[0081] Based on the first embodiment, step S40' of the refrigerant detection method of this embodiment includes:

[0082] Step S401 ′: If the vehicle air-conditioning pressure is within the static pressure range, the vehicle is controlled to enter a refrigerant test state.

[0083] It should be noted that if the vehicle air-conditioning pressure is in the static pressure range, it means that due to the existence of deviation, it is impossible to directly determine whether the refrigerant is sufficient, and further testing is required. Therefore, the vehicle can be controlled to enter the refrigerant test state, that is, the vehicle can be controlled to operate in the working conditions corresponding to the refrigerant test state.

[0084] Step S402 ′: when the vehicle maintains the refrigerant test state and the running time reaches a preset test time threshold, the current ambient temperature, the current vehicle interior temperature, the current heat exchanger temperature and the current air-conditioning pressure are obtained.

[0085] It should be noted that the preset test duration threshold can be pre-set by the administrator of the refrigerant detection equipment or the vehicle manufacturer, for example, setting the preset test duration threshold to 5 minutes. The current ambient temperature can be the temperature value of the vehicle's current environment; the current interior temperature can be the current temperature value inside the vehicle; the current heat exchanger temperature can be the surface temperature on the outlet side of the heat exchanger (which may also be called an evaporator or condenser depending on the operating conditions) in the current vehicle air conditioner; and the current air conditioning pressure can be the air conditioning pressure of the current vehicle air conditioner.

[0086] Among them, the current ambient temperature, the current temperature inside the vehicle, the current heat exchanger temperature and the current air-conditioning pressure can all be collected through sensors set at corresponding positions. For example: the current ambient temperature is collected through a temperature sensor set outside the vehicle, and the current temperature inside the vehicle is collected through a temperature sensor set inside the vehicle cabin.

[0087] Step S403 ′: searching for the air-conditioning pressure threshold and the temperature difference threshold corresponding to the current ambient temperature.

[0088] It should be noted that the vehicle manufacturer or the manager of the refrigerant detection equipment can pre-calibrate the vehicle to determine that under different ambient temperatures, the amount of refrigerant in the vehicle air conditioner maintains the lower limit of the refrigerant amount, the vehicle maintains the refrigerant test state, and when the running time reaches the preset test time threshold, the air conditioning pressure threshold and temperature difference threshold of the vehicle air conditioner are stored in the second calibration data table. At this time, the specific implementation method of looking for the air conditioning pressure threshold and temperature difference threshold corresponding to the current ambient temperature can be to look up the air conditioning pressure threshold and temperature difference threshold corresponding to the current ambient temperature in the second calibration data table.

[0089] The temperature difference threshold may be obtained by subtracting the heat exchanger temperature from the collected vehicle interior temperature.

[0090] In actual use, due to the large calibration workload, it is impossible to calibrate for all ambient temperatures during actual calibration. Therefore, the calibration data that completely corresponds to the current ambient temperature may not exist in the second calibration data table. The air conditioning pressure threshold and the temperature difference threshold have a certain relationship with the ambient temperature, and can be linearly fitted. When the temperature difference is small, the linear relationship can be considered to be a straight line correlation. Therefore, when there is no calibration data corresponding to the current ambient temperature in the second calibration data table, the calibration data with the closest values ​​can be searched upward (i.e., higher temperature) and downward (i.e., lower temperature) according to the current ambient temperature. Then, the air conditioning pressure threshold and temperature difference threshold corresponding to the current ambient temperature are determined through linear calculation.

[0091] For example: assuming that the current ambient temperature is 8°C, and calibration is performed at intervals of 5°C, then the closest calibration data can be searched upwards based on the current ambient temperature, and the air-conditioning pressure threshold and temperature difference threshold corresponding to 10°C can be obtained. The closest calibration data can be searched downwards based on the current ambient temperature, and the air-conditioning pressure threshold and temperature difference threshold corresponding to 5°C can be obtained. Then, a linear calculation is performed based on the air-conditioning pressure threshold and temperature difference threshold corresponding to 5°C and 10°C, and the air-conditioning pressure threshold and temperature difference threshold corresponding to 8°C are obtained.

[0092] Similarly, when searching for the static air-conditioning pressure threshold corresponding to the ambient temperature, the first calibration data table may not contain data that completely corresponds to the ambient temperature. In this case, a similar method can be used for processing.

[0093] Step S404 ′: determining a current temperature difference according to the current vehicle interior temperature and the current heat exchanger temperature.

[0094] It should be noted that the current temperature difference can be determined based on the current vehicle interior temperature and the current heat exchanger temperature by subtracting the current heat exchanger temperature from the previous vehicle interior temperature and using the obtained difference as the current temperature difference.

[0095] Step S405 ′: comparing the current air-conditioning pressure with the air-conditioning pressure threshold, and comparing the current temperature difference with the temperature difference threshold, and determining whether the refrigerant is sufficient based on the comparison results.

[0096] It should be noted that by comparing the current air-conditioning pressure with the air-conditioning pressure threshold, the size relationship between the current refrigerant amount in the vehicle air-conditioning and the lower limit of the refrigerant amount can be indirectly determined through the size relationship of the air-conditioning pressures, and by comparing the current temperature difference with the temperature difference threshold, the size relationship between the current refrigerant amount in the vehicle air-conditioning and the lower limit of the refrigerant amount can be indirectly determined from the difference in cooling effects. Therefore, by comparing the current air-conditioning pressure with the air-conditioning pressure threshold, and comparing the current temperature difference with the temperature difference threshold, it can be determined whether the refrigerant is sufficient based on the two comparison results.

[0097] In a specific implementation, in order to minimize the possibility of misjudging the refrigerant shortage, step S405' in this embodiment may include:

[0098] Comparing the current air-conditioning pressure with the air-conditioning pressure threshold, and comparing the current temperature difference with the temperature difference threshold;

[0099] If the current air-conditioning pressure is less than the air-conditioning pressure threshold, and the current temperature difference is less than the temperature difference threshold, it is determined that the refrigerant is insufficient;

[0100] If the current air-conditioning pressure is greater than or equal to the air-conditioning pressure threshold, or the current temperature difference is greater than or equal to the temperature difference threshold, it is determined that the refrigerant is sufficient.

[0101] It should be noted that if the current air-conditioning pressure is less than the air-conditioning pressure threshold, and the current temperature difference is less than the temperature difference threshold, it means that regardless of whether it is judged from the cooling effect or the air-conditioning pressure, it can be determined that the amount of refrigerant in the vehicle air-conditioning is less than the lower limit of the refrigerant amount. Therefore, it can be determined that the refrigerant is insufficient.

[0102] If the current air-conditioning pressure is greater than or equal to the air-conditioning pressure threshold, or the current temperature difference is greater than or equal to the temperature difference threshold, it means that at this time, judging from the cooling effect or the air-conditioning pressure, one of the judgment results is that the amount of refrigerant in the vehicle air-conditioning is not less than the lower limit of the refrigerant amount. At this time, in order to minimize the prompt of insufficient refrigerant, it can be determined that the refrigerant is sufficient.

[0103] Of course, if you want to ensure the comprehensiveness of the detection, you can also judge from the cooling effect or the air-conditioning pressure. If the result of any of the judgments is that the amount of refrigerant in the car air-conditioning is less than the lower limit of the refrigerant amount, it is determined that the refrigerant is insufficient.

[0104] In a specific implementation, in order to ensure the effect of the refrigerant test, step S401' in this embodiment may include:

[0105] If the vehicle air-conditioning pressure is within the static pressure range, the vehicle is controlled to idle, and the vehicle air-conditioning is controlled to operate in a full-cooling internal circulation mode.

[0106] It should be noted that due to the complexity of the actual vehicle operating conditions, the impact on the vehicle air conditioner is different under different operating conditions. In order to minimize the impact of the vehicle engine on the vehicle air conditioner, the vehicle idling speed can be controlled to make the engine in the vehicle run at the lowest stable speed; and in order to maximize the difference between the temperature inside the vehicle and the evaporator temperature, and reduce the impact of external air on the vehicle air conditioner, for easy judgment, the air conditioner can be operated in a blowing surface full-cooling internal circulation mode, that is, the vehicle is operated in a blowing surface, full-speed cooling, and air internal circulation mode.

[0107] If the car air conditioner has air outlet gears, in order to maximize the difference between the temperature inside the car and the evaporator temperature, the car air conditioner can also be operated at the maximum air outlet gear to ensure that it can lower the temperature inside the car as quickly as possible and form a larger difference.

[0108] In a specific implementation, since there may be a driver or passenger in the vehicle during the refrigerant test, if the air is directly blown at the maximum gear, it may result in a very poor experience for them. To avoid this situation, in this embodiment, if the vehicle air conditioner pressure is within the static pressure range, the steps of controlling the vehicle to idle and controlling the vehicle air conditioner to operate in the full-cooling internal circulation mode with blowing on the surfaces may include:

[0109] If the vehicle air-conditioning pressure is within the static pressure range, the vehicle is controlled to idle, and the vehicle air-conditioning is operated in a full-cooling internal circulation mode according to a preset gear;

[0110] Accordingly, the step of searching for the air-conditioning pressure threshold and the temperature difference threshold corresponding to the current ambient temperature may include:

[0111] The air conditioning pressure threshold and the temperature difference threshold corresponding to the current ambient temperature and the preset gear position are searched.

[0112] It should be noted that the preset gear position may be the air outlet gear position pre-set by the driver or passenger of the vehicle, or may be the air outlet gear position of the previous vehicle air conditioner, and this embodiment does not impose any restrictions on this.

[0113] In actual use, due to the differences in gears during refrigerant testing, in order to ensure the accuracy of refrigerant detection, the manager of the refrigerant detection equipment or the manufacturer of the vehicle can calibrate for different air outlet gears when constructing the second calibration data table. At this time, the air conditioning pressure threshold and temperature difference threshold corresponding to the current ambient temperature and the preset gear can be found in the second calibration data table.

[0114] Of course, in order to distinguish the relevant data of different air outlet gears, the manager of the refrigerant detection equipment or the manufacturer of the vehicle can set up a second calibration data table for each air outlet gear when calibrating. At this time, to find the air-conditioning pressure threshold and temperature difference threshold corresponding to the current ambient temperature and the preset gear, you can first obtain the second calibration data table corresponding to the preset gear, and then search the air-conditioning pressure threshold and temperature difference threshold corresponding to the current ambient temperature in the second calibration data table corresponding to the preset gear.

[0115] When it is difficult to determine whether the refrigerant is sufficient simply by using the static air-conditioning pressure threshold, this embodiment controls the vehicle to operate in the operating conditions corresponding to the refrigerant test state, and re-collects data after running for a certain period of time, and makes a comprehensive judgment based on the air-conditioning pressure and the cooling effect. This ensures that in this case, whether the refrigerant of the vehicle air-conditioning is sufficient is still detected.

[0116] In addition, an embodiment of the present invention further provides a storage medium, on which a refrigerant detection program is stored. When the refrigerant detection program is executed by a processor, the steps of the refrigerant detection method described above are implemented.

[0117] Reference Figure 4 , Figure 4 This is a structural block diagram of the first embodiment of the refrigerant detection device of the present invention.

[0118] like Figure 4 As shown, the refrigerant detection device proposed in the embodiment of the present invention includes:

[0119] An acquisition module 10 is configured to acquire the ambient temperature and the vehicle air conditioning pressure if a cold start of the vehicle is detected;

[0120] A search module 20 is configured to search for a static air conditioning pressure threshold corresponding to the ambient temperature, where the static air conditioning pressure threshold is a static air conditioning pressure value corresponding to a lower limit of the refrigerant quantity, and the lower limit of the refrigerant quantity is a minimum value of the refrigerant quantity required to maintain normal operation of the vehicle air conditioner;

[0121] a determination module 30 for determining a static pressure interval according to an error value and the static air conditioning pressure threshold, wherein the error value is determined according to a sensor tolerance and / or a vehicle cabin heat impact;

[0122] The determination module 40 is configured to compare the vehicle air-conditioning pressure with the static pressure range to determine whether the refrigerant is sufficient.

[0123] This embodiment detects the presence of refrigerant by obtaining the ambient temperature and onboard air conditioning pressure upon detecting a cold start of the vehicle; searching for a static air conditioning pressure threshold corresponding to the ambient temperature; determining a static pressure interval based on an error value and the static air conditioning pressure threshold; and comparing the onboard air conditioning pressure with the static pressure interval to determine whether refrigerant is sufficient. Because the static air conditioning pressure threshold corresponding to the calibrated lower limit of refrigerant volume at that ambient temperature is found by searching for the ambient temperature, the onboard air conditioning pressure is compared with the calibrated static air conditioning pressure threshold, and the effects of the sensor or cabin temperature are taken into account during the comparison process, ensuring accurate detection of refrigerant sufficiency in the onboard air conditioning, thereby achieving refrigerant detection for the vehicle's onboard air conditioning.

[0124] Furthermore, the judgment module 40 is also used to determine that the refrigerant is sufficient if the vehicle air-conditioning pressure is less than the lower limit of the static pressure interval; to determine that the refrigerant is insufficient if the vehicle air-conditioning pressure is greater than the upper limit of the static pressure interval; and to perform a refrigerant test to determine whether the refrigerant is sufficient if the vehicle air-conditioning pressure is within the static pressure interval.

[0125] Furthermore, the judgment module 40 is also used to control the vehicle to enter the refrigerant test state if the vehicle air-conditioning pressure is in the static pressure range; when the vehicle maintains the refrigerant test state and the running time reaches the preset test time threshold, obtain the current ambient temperature, the current vehicle interior temperature, the current heat exchanger temperature and the current air-conditioning pressure; find the air-conditioning pressure threshold and the temperature difference threshold corresponding to the current ambient temperature; determine the current temperature difference according to the current vehicle interior temperature and the current heat exchanger temperature; compare the current air-conditioning pressure with the air-conditioning pressure threshold, and compare the current temperature difference with the temperature difference threshold, and determine whether the refrigerant is sufficient according to the comparison result.

[0126] Furthermore, the determination module 40 is further configured to control the vehicle to idle if the vehicle air-conditioning pressure is within the static pressure range, and to control the vehicle air-conditioning to operate in a full-cooling internal circulation mode.

[0127] Furthermore, the determination module 40 is further configured to control the vehicle to idle if the vehicle air-conditioning pressure is within the static pressure range, and the vehicle air-conditioning operates in a full-cooling internal circulation mode according to a preset gear position;

[0128] The determination module 40 is further configured to search for an air-conditioning pressure threshold and a temperature difference threshold corresponding to the current ambient temperature and the preset gear position.

[0129] Furthermore, the determination module 40 is also used to compare the current air-conditioning pressure with the air-conditioning pressure threshold, and to compare the current temperature difference with the temperature difference threshold; if the current air-conditioning pressure is less than the air-conditioning pressure threshold, and the current temperature difference is less than the temperature difference threshold, it is determined that the refrigerant is insufficient; if the current air-conditioning pressure is greater than or equal to the air-conditioning pressure threshold, or the current temperature difference is greater than or equal to the temperature difference threshold, it is determined that the refrigerant is sufficient.

[0130] Furthermore, the acquisition module 10 is also used to obtain the ambient temperature and cooling water temperature if the vehicle is detected to be started, and the cooling water temperature is the vehicle engine coolant temperature; if the difference between the ambient temperature and the cooling water temperature is less than or equal to a preset threshold, it is determined that the vehicle cold start is detected.

[0131] It should be understood that the above is only an example and does not constitute any limitation to the technical solution of the present invention. In specific applications, those skilled in the art can make settings as needed, and the present invention does not impose any limitation on this.

[0132] It should be noted that the workflow described above is merely illustrative and does not limit the scope of protection of the present invention. In practical applications, technicians in this field can select part or all of it according to actual needs to achieve the purpose of the embodiment scheme, and no limitation is made here.

[0133] In addition, for technical details not fully described in this embodiment, reference can be made to the refrigerant detection method provided in any embodiment of the present invention, and will not be repeated here.

[0134] In addition, it should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or system comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or system. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or system comprising the element.

[0135] The serial numbers of the above embodiments of the present invention are for description only and do not represent the advantages or disadvantages of the embodiments.

[0136] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform, or of course by hardware, but in many cases the former is a better embodiment. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. The computer software product is stored in a storage medium (such as a read-only memory (ROM) / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for enabling a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present invention.

[0137] The above are only preferred embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A refrigerant detection method, characterized in that: The refrigerant detection method comprises: If a cold start of the vehicle is detected, the ambient temperature and the vehicle air conditioning pressure are obtained; Finding a static air conditioning pressure threshold corresponding to the ambient temperature, where the static air conditioning pressure threshold is a static air conditioning pressure value corresponding to a lower limit of the refrigerant quantity, where the lower limit of the refrigerant quantity is a minimum value of the refrigerant quantity required to maintain normal operation of the vehicle air conditioner; determining a static pressure range according to an error value and the static air conditioning pressure threshold, wherein the error value is determined according to a sensor tolerance and / or a vehicle cabin heat impact; The vehicle air conditioning pressure is compared with the static pressure range to determine whether the refrigerant is sufficient.

2. The refrigerant detection method according to claim 1, wherein: The comparing the vehicle air conditioner pressure with the static pressure range to determine whether the refrigerant is sufficient includes: If the vehicle air-conditioning pressure is less than the lower limit of the static pressure range, it is determined that the refrigerant is sufficient; If the vehicle air-conditioning pressure is greater than the upper limit of the static pressure range, it is determined that the refrigerant is insufficient; If the vehicle air-conditioning pressure is within the static pressure range, a refrigerant test is performed to determine whether the refrigerant is sufficient.

3. The refrigerant detection method according to claim 2, wherein: If the vehicle air conditioner pressure is within the static pressure range, a refrigerant test is performed to determine whether the refrigerant is sufficient, including: If the vehicle air-conditioning pressure is within the static pressure range, controlling the vehicle to enter a refrigerant test state; When the vehicle maintains the refrigerant test state and the running time reaches a preset test time threshold, the current ambient temperature, the current vehicle interior temperature, the current heat exchanger temperature and the current air conditioning pressure are obtained; Find the air conditioning pressure threshold and temperature difference threshold corresponding to the current ambient temperature; determining a current temperature difference according to the current vehicle interior temperature and the current heat exchanger temperature; The current air-conditioning pressure is compared with the air-conditioning pressure threshold, and the current temperature difference is compared with the temperature difference threshold, and whether the refrigerant is sufficient is determined according to the comparison results.

4. The refrigerant detection method according to claim 3, wherein: If the vehicle air-conditioning pressure is within the static pressure range, controlling the vehicle to enter a refrigerant test state includes: If the vehicle air-conditioning pressure is within the static pressure range, the vehicle is controlled to idle, and the vehicle air-conditioning is controlled to operate in a full-cooling internal circulation mode.

5. The refrigerant detection method according to claim 4, wherein: If the vehicle air conditioner pressure is within the static pressure range, the vehicle is controlled to idle, and the vehicle air conditioner is controlled to operate in a full-cooling internal circulation mode, including: If the vehicle air-conditioning pressure is within the static pressure range, the vehicle is controlled to idle, and the vehicle air-conditioning is operated in a full-cooling internal circulation mode according to a preset gear; The step of searching for the air-conditioning pressure threshold and the temperature difference threshold corresponding to the current ambient temperature includes: The air conditioning pressure threshold and the temperature difference threshold corresponding to the current ambient temperature and the preset gear position are searched.

6. The refrigerant detection method according to claim 3, wherein: The comparing the current air-conditioning pressure with the air-conditioning pressure threshold, and comparing the current temperature difference with the temperature difference threshold, and determining whether the refrigerant is sufficient according to the comparison results, includes: Comparing the current air-conditioning pressure with the air-conditioning pressure threshold, and comparing the current temperature difference with the temperature difference threshold; If the current air-conditioning pressure is less than the air-conditioning pressure threshold, and the current temperature difference is less than the temperature difference threshold, it is determined that the refrigerant is insufficient; If the current air-conditioning pressure is greater than or equal to the air-conditioning pressure threshold, or the current temperature difference is greater than or equal to the temperature difference threshold, it is determined that the refrigerant is sufficient.

7. The refrigerant detection method according to any one of claims 1 to 6, characterized in that: If a cold start of the vehicle is detected, before obtaining the ambient temperature and the vehicle air-conditioning pressure, the method further includes: If the vehicle is detected to be started, the ambient temperature and the cooling water temperature are obtained, where the cooling water temperature is the vehicle engine coolant temperature; If the difference between the ambient temperature and the cooling water temperature is less than or equal to a preset threshold, it is determined that a vehicle cold start is detected.

8. A refrigerant detection device, characterized in that: The refrigerant detection device comprises: An acquisition module is used to obtain the ambient temperature and the vehicle air conditioning pressure if a cold start of the vehicle is detected; a search module for searching a static air-conditioning pressure threshold corresponding to the ambient temperature, wherein the static air-conditioning pressure threshold is a static air-conditioning pressure value corresponding to a lower limit of a refrigerant quantity, wherein the lower limit of a refrigerant quantity is a minimum value of a refrigerant quantity required to maintain normal operation of the vehicle air-conditioning; a determination module, configured to determine a static pressure interval according to an error value and the static air conditioning pressure threshold, wherein the error value is determined according to a sensor tolerance and / or a vehicle cabin heat impact; The determination module is used to compare the vehicle air-conditioning pressure with the static pressure range to determine whether the refrigerant is sufficient.

9. A refrigerant detection device, characterized in that: The refrigerant detection device includes: a processor, a memory, and a refrigerant detection program stored in the memory and executable on the processor. When the refrigerant detection program is executed by the processor, the steps of the refrigerant detection method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a refrigerant detection program, which, when executed, implements the steps of the refrigerant detection method according to any one of claims 1 to 7.

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