A new energy vehicle air conditioner refrigerant leakage early warning method

Abstract

The application provides a new energy automobile air conditioner refrigerant leakage early warning method for quickly judging whether the new energy automobile air conditioner refrigerant leaks or not. The implementation of the method depends on the electric compressor, the vehicle controller and the air conditioner system capable of detecting the air conditioner system pressure in the new energy vehicle. The method needs the vehicle controller to control the air conditioner system to work according to the preset working condition when the vehicle is in a certain common working condition. After stable operation for a period of time, the vehicle controller collects the parameters of the air conditioner system such as the system high pressure. The collected parameters after stable operation of the air conditioner system are compared with the preset values. The refrigerant leakage state of the air conditioner system at this time is judged and output to the vehicle display instrument. Finally, the refrigerant leakage early warning is carried out for the customer. The lack of refrigerant cooling or heating during the vehicle driving process is avoided, the vehicle power is limited or even stranded, and the vehicle comfort is improved.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicles, and more specifically, to a method for early warning of refrigerant leakage in the air conditioning system of new energy vehicles. Background Technology

[0002] Currently, the automotive industry generally lacks effective early warning mechanisms for refrigerant leaks in air conditioning systems. Users typically only inspect and repair refrigerant after experiencing a significant drop in cooling efficiency or even system failure, severely compromising user convenience and comfort. This is especially true for new energy vehicles, where the battery thermal management system heavily relies on refrigerant for cooling / heating. Refrigerant deficiency directly leads to battery overheating or undercooling, causing safety hazards such as limited vehicle power or even breakdowns, with consequences more severe than in traditional gasoline vehicles. While existing technologies include methods to detect leaks by monitoring the time it takes for the air conditioner to reach the target temperature after startup and combining this with the status of doors and windows, these methods are designed for home air conditioning scenarios and cannot adapt to the dynamic operating conditions of vehicles. Other solutions require real-time comparison of multiple parameters such as outlet air temperature, condenser pressure, and refrigerant supercooling / superheating, which not only involves complex judgment logic but also imposes stringent requirements on sensor accuracy and system operating conditions, significantly limiting their applicability to various vehicles. It is evident that the above solutions all have significant drawbacks: (1) they rely on the high-frequency active operation of the air conditioner, which cannot meet the detection needs of all four seasons; (2) the large amount of parameter collection leads to high system deployment costs and poor robustness; and (3) the detection process is prone to interfering with the user's normal vehicle use. Therefore, there is an urgent need for a refrigerant leak detection solution that can operate under concealed working conditions, has simplified judgment conditions, and is applicable to all seasons. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the purpose of this invention is to provide an early warning method for refrigerant leakage in the air conditioning of new energy vehicles. By setting different refrigerant leakage judgment conditions based on different ambient temperatures under different operating conditions, the method can determine whether the air conditioning refrigerant is leaking, thereby preventing the vehicle from being limited in power or even breaking down due to lack of refrigerant cooling or heating during driving, and improving the comfort of vehicle use.

[0004] To achieve the above-mentioned technical effects, the present invention adopts the following technical solution:

[0005] A method for detecting refrigerant leakage in vehicle air conditioning systems includes the following steps:

[0006] S1. Determine whether the vehicle is locked or charging. If either state is met, enter the detection mode.

[0007] S2. Trigger detection conditions based on vehicle operating conditions: When the vehicle is locked, activate the detection mode when the locking duration reaches the first preset duration; when the vehicle is charging, activate the detection mode when the charging duration reaches the second preset duration.

[0008] S3. Set the air conditioning operating mode according to the current ambient temperature and vehicle operating conditions:

[0009] a) For the locked vehicle state: Control the air conditioning system to operate in the preset passenger compartment cooling mode and continue to operate for the third preset duration;

[0010] b) For the charging state: i) When the ambient temperature is higher than the set threshold, control the air conditioning system to run the preset power battery cooling mode and run it for a fourth preset time; ii) When the ambient temperature is lower than the set threshold, control the air conditioning system to run the preset power battery heating mode and run it for a fourth preset time.

[0011] S4. After completing step S3, wait for the fifth preset time period, collect the high pressure value of the air conditioning system, and compare it with the preset high pressure range corresponding to the current ambient temperature. If the collected high pressure value is lower than the lower limit of the preset high pressure range, it is determined that the refrigerant is leaking; if the collected high pressure is within the preset high pressure range, it is determined that the refrigerant is normal.

[0012] S5. If a refrigerant leak is detected, trigger the vehicle instrument alarm and terminate the process; otherwise, terminate the process directly.

[0013] Optionally, the first preset duration is 2 hours, the second preset duration is 15 minutes, the third preset duration is 10 minutes, the fourth preset duration is 5 minutes, and the fifth preset duration is 10 minutes.

[0014] Optionally, in step S3, the control parameters for the preset occupant cabin cooling condition include: compressor speed of 2000 rpm, blower speed of 3, damper mode of full cooling internal circulation, and air outlet mode of blowing air onto the face.

[0015] Optionally, in step S3, the control parameters for the preset power battery cooling condition include: compressor speed 2000 rpm, battery pack cooling electronic expansion valve opening 20%, and battery cooling water pump turned on.

[0016] Optionally, in step S3, the control parameters for the preset power battery heating condition include: compressor speed 2000 rpm, enabling heat pump heating battery pack mode, and turning on the battery heating water pump.

[0017] Optionally, the preset high-pressure range in step S4 is a standard safety value preset according to the vehicle model.

[0018] Optionally, the alarm in step S5 may include a flashing dashboard warning light or a maintenance notification pushed by the vehicle system.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The method provided by this invention only performs the test when the customer is away from the vehicle or charging, and will not cause any inconvenience to the customer's vehicle use.

[0021] 2. The method provided by this invention simplifies the parameters for determining air conditioner refrigerant leakage. It only requires a high-pressure sensor to measure the high-pressure, eliminating the need for additional sensors and reducing costs.

[0022] 3. The method provided by this invention has a wide range of applications and simple control logic. It can provide early warnings to car owners to check and replenish the refrigerant in the car's air conditioning system, thus avoiding vehicle power limitations and the inability of the air conditioning to cool or heat due to a lack of refrigerant during vehicle operation. Attached Figure Description

[0023] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0024] Figure 1 This is a flowchart illustrating the early warning and control method for refrigerant leakage in the air conditioning system of a new energy vehicle as described in the embodiment.

[0025] Figure 2 This is a schematic diagram illustrating the refrigerant leakage determination criteria for a specific vehicle model as described in the embodiment. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0028] It should be noted that similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, all directional indications (such as up, down, left, right, front, back, bottom, etc.) in this application are only used to explain the relative positional relationships and movements between components in a specific orientation (as shown in the figures). If the specific orientation changes, the directional indication will also change accordingly. Furthermore, descriptions involving "first," "second," etc., in this application are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated.

[0029] like Figure 1 As shown, this embodiment provides a method for early warning of refrigerant leakage in the air conditioning system of a new energy vehicle. This method is used to quickly determine whether the refrigerant in the air conditioning system of a new energy vehicle is leaking. The implementation of this method relies on the electric compressor, vehicle controller, and air conditioning system capable of detecting the air conditioning system pressure in the new energy vehicle. This method requires the vehicle controller to operate the air conditioning system according to preset operating conditions under certain common operating conditions. After stable operation for a period of time, the vehicle controller collects parameters of the air conditioning system, such as the system high-pressure pressure. The collected parameters after stable operation are compared with preset values ​​to determine the refrigerant leakage status of the air conditioning system at this time, and outputs the result to the vehicle's display instrument panel, ultimately providing an early warning of refrigerant leakage to the customer. Specifically, it includes the following steps:

[0030] Step 1: Determine if the vehicle is locked or charging. If so, the system is in a pending detection state, waiting for subsequent conditions to trigger. This step is the starting point of the entire process, ensuring the vehicle has entered a possible detection scenario. Common vehicle operating conditions in this method include, but are not limited to: 1. Vehicle power battery charging state: In this state, the power battery generates a lot of heat, and the air conditioning system frequently activates to cool the power battery. Under this state, controlling the air conditioning system to operate according to preset conditions makes it less likely for customers to mistakenly believe the vehicle is malfunctioning. 2. Passenger locked and unoccupied state: In this state, after determining that the customer has locked and unoccupied the vehicle for a certain period of time, and after no one is in the vehicle, the air conditioning system is activated to run a preset condition. Running the refrigerant leak test condition in the above two common vehicle states has the following advantages: Firstly, running the air conditioning system to detect refrigerant leaks in the above two vehicle scenarios is relatively discreet, with minimal impact on customers. Secondly, the above two vehicle scenarios are common operating conditions for most customers, and the frequency of refrigerant leak detection is consistent with the requirements, avoiding detection that is too frequent or too infrequent.

[0031] Step 2: The system evaluates the current vehicle's operating condition to determine if it meets the refrigerant leak detection conditions under different states. When the vehicle is locked, if the locking time reaches 2 hours, the system enters the refrigerant leak detection mode. When the vehicle is charging, if the charging time reaches 15 minutes, the system enters the refrigerant leak detection mode. If none of the above conditions are met (e.g., insufficient locking time or insufficient charging time), the process ends immediately without detection. This optimizes resource utilization and avoids unnecessary system operation.

[0032] Step 3: Based on the current ambient temperature and vehicle status, the system activates the air conditioning system and selects and runs the preset air conditioning settings. Specifically:

[0033] When the vehicle has been locked for 2 hours, the air conditioning system is controlled to operate under the preset passenger compartment cooling conditions: the air conditioning system compressor speed is set to 2000rpm, the blower speed is adjusted to level 3, the damper mode is adjusted to full cooling internal circulation, and the air outlet mode is set to face blowing. The air conditioning system operates under the above conditions for 10 minutes.

[0034] When the vehicle has been charging for 15 minutes and the ambient temperature is high, the air conditioning system will operate under the preset power battery cooling conditions: the air conditioning compressor speed will be set to 2000 rpm, the air conditioning system will switch to battery pack cooling mode, the opening of the battery pack cooling electronic expansion valve will be set to 20%, the battery cooling water pump will be turned on, and the air conditioning system will continue to operate under the above conditions for 5 minutes.

[0035] When the vehicle has been charging for 15 minutes and the ambient temperature is low, the air conditioning system will operate under the preset power battery heating condition: the air conditioning compressor speed will be set to 2000 rpm, the air conditioning system will switch to heat pump heating battery pack mode, the battery heating water pump will be turned on, and the air conditioning system will operate under the above condition for 5 minutes.

[0036] The core of this step is to operate the relevant systems under safe conditions to prepare for subsequent stress testing. After operation, the system enters the data recording phase. One or more preset operating conditions can be used, depending on the ambient temperature of the vehicle and whether it is parked, charging, or under other conditions.

[0037] Step 4: After completing the preset operating conditions, wait 10 minutes to collect the high-pressure value of the air conditioning system and compare it with the preset high-pressure value range to determine the refrigerant leakage status. After the operation in Step 3 is completed (Note: Regardless of whether the vehicle is locked or in charging mode, the system will wait 10 minutes to stabilize the detection data), the system records the current high-pressure value of the air conditioning system and compares and analyzes it with the preset normal refrigerant pressure value range based on the current ambient temperature collected by the vehicle. The normal refrigerant pressure value range is a standard safety value set based on the vehicle model. Figure 2 The diagram illustrates the refrigerant leakage detection criteria for a specific vehicle model. If the collected high-pressure reading is lower than the preset lower limit of the normal refrigerant pressure value, it indicates a refrigerant leak. If the collected high-pressure reading is within the preset normal refrigerant pressure value range, it indicates that the air conditioning system refrigerant is normal. If the collected high-pressure reading is higher than the preset normal refrigerant pressure value upper limit, it indicates that there is too much refrigerant. Figure 2 This only represents parameters for a specific vehicle model; the specific values ​​can be adjusted according to different vehicle models.

[0038] Step 5: Address the leak and end the process; If a refrigerant leak is detected in Step 4, the system will immediately trigger an alarm on the dashboard (e.g., by flashing a warning light on the dashboard or by sending a maintenance notification to the vehicle system to remind the owner to have the vehicle inspected), and then end the process. If no leak occurs, the process will end directly (no alarm required).

[0039] The early warning method for refrigerant leakage in new energy vehicle air conditioning provided in this embodiment simplifies the judgment conditions by setting specific operating conditions to determine whether the air conditioning refrigerant is leaking. It uses only the high-pressure of the air conditioning system as the judgment value, simplifying the control logic and judgment parameters, and avoiding inconvenience to customers. Furthermore, it can set different refrigerant leakage judgment conditions according to different ambient temperatures, making it applicable to almost all new energy vehicles. Its wide applicability allows for early warnings to vehicle owners to check and replenish the car's air conditioning refrigerant, preventing the discovery of air conditioning malfunctions during vehicle use and improving driving comfort. Since current new energy batteries rely on air conditioning refrigerant for cooling or heating, early warnings to vehicle owners prevent vehicle power limitations or even breakdowns due to insufficient refrigerant cooling or heating during driving.

[0040] The specific embodiments of the present invention have been described above. Based on the above description, those skilled in the art can make various changes and modifications without departing from the technical concept of the present invention.

Claims

1. A method for early warning of leakage of a new energy vehicle air conditioner refrigerant, characterized in that, Includes the following steps: S1. Determine whether the vehicle is locked and unattended or charging. If either state is met, enter the detection mode. S2. Trigger detection conditions based on vehicle operating conditions: When the vehicle is locked and the vehicle is not in use, the detection mode is activated when the vehicle is locked for a duration of a first preset duration; when the vehicle is charging, the detection mode is activated when the charging duration is a second preset duration. S3. Set the air conditioning operating mode according to the current ambient temperature and vehicle operating conditions: a) For the locked vehicle state: Control the air conditioning system to operate in the preset passenger compartment cooling mode and continue to operate for the third preset duration; b) For the charging state: i) When the ambient temperature is higher than the set threshold, control the air conditioning system to run the preset power battery cooling mode and run it for a fourth preset time; ii) When the ambient temperature is lower than the set threshold, control the air conditioning system to run the preset power battery heating mode and run it for a fourth preset time. S4. After completing step S3, wait for the fifth preset time period, collect the high pressure value of the air conditioning system, and compare it with the preset high pressure range corresponding to the current ambient temperature. If the collected high pressure value is lower than the lower limit of the preset high pressure range, it is determined that the refrigerant is leaking; if the collected high pressure is within the preset high pressure range, it is determined that the refrigerant is normal. S5. If a refrigerant leak is detected, trigger the vehicle instrument panel alarm and terminate the process; otherwise, terminate the process directly. The first preset duration is 2 hours, the second preset duration is 15 minutes, the third preset duration is 10 minutes, the fourth preset duration is 5 minutes, and the fifth preset duration is 10 minutes; In step S3, the control parameters for the preset occupant cabin cooling condition include: compressor speed of 2000 rpm, blower speed of 3, damper mode of full cooling internal circulation, and air outlet mode of blowing towards the face. In step S3, the control parameters of the preset power battery cooling condition include: compressor speed 2000 rpm, battery pack cooling electronic expansion valve opening 20%, and battery cooling water pump turned on. In step S3, the control parameters for the preset power battery heating condition include: compressor speed 2000 rpm, enabling heat pump heating battery pack mode, and turning on battery heating water pump.

2. The early warning method for refrigerant leakage in the air conditioning system of new energy vehicles according to claim 1, characterized in that, The preset high pressure range in step S4 is a standard safety value preset according to the vehicle model.

3. The early warning method for refrigerant leakage in the air conditioning system of new energy vehicles according to claim 1, characterized in that, The alarms in step S5 include flashing dashboard warning lights or a maintenance notification pushed by the vehicle system.

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