Air conditioner and control method, device, storage medium and computer program product thereof

Abstract

The application discloses an air conditioner and a control method, device, storage medium and computer program product thereof. The method comprises the following steps: after the air conditioner is powered on, if the refrigerant detection device can work, determining whether the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold; if it is determined that the current refrigerant concentration detected by the refrigerant detection device is less than the preset concentration threshold, combining the current working environment temperature of the refrigerant detection device, the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device to determine whether the indoor unit leaks refrigerant; and if it is determined that the indoor unit leaks refrigerant, controlling the air conditioner to execute a preset refrigerant leakage fault protection mechanism. According to the scheme, the refrigerant concentration detected by the refrigerant sensor and the working environment temperature at the position of the refrigerant sensor are combined to accurately determine whether the air conditioner leaks refrigerant, false positives are avoided, and the reliability of the refrigerant leakage protection is improved.

Description

Technical Field

[0001] This invention belongs to the field of air conditioner technology, specifically relating to an air conditioner control method, device, air conditioner, storage medium, and computer program product, and particularly to a refrigerant leakage protection control method, device, air conditioner, storage medium, and computer program product for an R32 combustible refrigerant air conditioner. Background Technology

[0002] R32 refrigerant is increasingly used in air conditioners. Refrigerant leaks not only significantly reduce the cooling or heating performance of the air conditioner, causing indoor temperatures to fail to reach set levels and affecting user comfort, but also pose safety hazards. This is especially true for multi-split units, where a single outdoor unit connects to multiple indoor units. Each indoor unit serves a relatively small room, and the outdoor unit requires a larger refrigerant charge to ensure the effectiveness of all indoor units compared to single-split models. Since the outdoor unit and all indoor units are part of the same system, when an indoor unit leaks, refrigerant from all outdoor units will leak towards the leak point. This refrigerant accumulation in the same room can easily cause the refrigerant concentration to reach the lower flammability limit (LFL) of R32 refrigerant, potentially leading to fires and explosions. Therefore, detecting refrigerant leaks is crucial.

[0003] However, the detection methods for refrigerant leaks in air conditioners in the relevant solutions are often not sensitive enough. There may be false alarms when there is no leak, which may cause the leak protection to shut down the unit and affect the user experience.

[0004] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0005] The purpose of this invention is to provide a control method, device, air conditioner, storage medium, and computer program product for an air conditioner, to solve the problem in related solutions where false alarms occur when there is no leak, leading to leak protection shutdown and affecting user experience. This invention achieves accurate determination of refrigerant leakage by combining the refrigerant concentration detected by the refrigerant sensor with the ambient temperature at the sensor's location. It avoids false alarms caused by distortion of the refrigerant concentration detected by the sensor due to changes in the ambient temperature at the sensor's location, thus improving the reliability of refrigerant leak protection and enhancing the user experience.

[0006] This invention provides a control method for an air conditioner, wherein the indoor unit of the air conditioner has a refrigerant detection device; the refrigerant detection device is used to detect the refrigerant concentration at its own location, denoted as the current refrigerant concentration detected by the refrigerant detection device; the control method for the air conditioner includes: after the air conditioner is powered on, and assuming the refrigerant detection device is capable of operating, acquiring the current refrigerant concentration detected by the refrigerant detection device; acquiring the current operating ambient temperature of the refrigerant detection device; determining whether the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold; if it is determined that the current refrigerant concentration detected by the refrigerant detection device is less than the preset concentration threshold, controlling the air conditioner to maintain its current state; if it is determined that the current refrigerant concentration detected by the refrigerant detection device is greater than or equal to the preset concentration threshold, determining whether the indoor unit has experienced a refrigerant leak by combining the current operating ambient temperature of the refrigerant detection device, the current state of the air conditioner, and the current refrigerant concentration detected by the refrigerant detection device; and if it is determined that the indoor unit has experienced a refrigerant leak, controlling the air conditioner to execute a preset refrigerant leak fault protection mechanism.

[0007] In some embodiments, the indoor unit further includes a temperature detection device; the temperature detection device includes at least one of the following: a first temperature detection module, a second temperature detection module, and a third temperature detection module; wherein, the first temperature detection module is used to detect the temperature at a location within a set distance range from the refrigerant detection device; the second temperature detection module is used to detect the pipe temperature of the indoor heat exchanger of the indoor unit; the third temperature detection module is used to detect the indoor ambient temperature of the indoor unit; obtaining the current operating ambient temperature of the refrigerant detection device includes any of the following methods: a first method: obtaining the temperature at a location within a set distance range from the refrigerant detection device detected by the first temperature detection module, and recording it as the current operating ambient temperature of the refrigerant detection device; a second method: obtaining the pipe temperature of the indoor heat exchanger of the indoor unit detected by the second temperature detection module, and obtaining the indoor ambient temperature of the indoor unit detected by the third temperature detection module; using the pipe temperature of the indoor heat exchanger of the indoor unit or the indoor ambient temperature of the indoor unit as the current operating ambient temperature of the refrigerant detection device.

[0008] In some implementations, determining whether the indoor unit has experienced a refrigerant leak involves combining the current operating ambient temperature of the refrigerant detection device, the current state of the air conditioner, and the current refrigerant concentration detected by the refrigerant detection device. This includes: determining the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device within a preset first time period; and determining whether the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner; if the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device is less than the preset temperature threshold in the current target operating mode of the air conditioner, then determining that the indoor unit has experienced a refrigerant leak; if the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, then determining whether the indoor unit has experienced a refrigerant leak involves combining the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device.

[0009] In some implementations, determining whether the indoor unit has experienced a refrigerant leak involves combining the current state of the air conditioner with the current refrigerant concentration detected by the refrigerant detection device. This includes: determining whether the current state of the air conditioner is a preset off state or a preset running state; if the current state of the air conditioner is determined to be the off state, then determining that the indoor unit has experienced a refrigerant leak; if the current state of the air conditioner is determined to be the running state, then controlling the air conditioner to shut down, and then determining whether the indoor unit has experienced a refrigerant leak based on the current refrigerant concentration detected by the refrigerant detection device.

[0010] In some implementations, determining whether the indoor unit has experienced a refrigerant leak based on the current refrigerant concentration detected by the refrigerant detection device includes: determining whether the current refrigerant concentration detected by the refrigerant detection device continues to rise within a preset second time period; if it is determined that the current refrigerant concentration detected by the refrigerant detection device continues to rise within the preset second time period, then determining that the indoor unit has experienced a refrigerant leak; if it is determined that the current refrigerant concentration detected by the refrigerant detection device does not continue to rise within the preset second time period, then determining that the indoor unit has not experienced a refrigerant leak, and controlling the air conditioner to restart and resume operation.

[0011] In some implementations, determining the maximum temperature difference of the current operating environment temperature of the refrigerant detection device within a preset first time period includes any of the following determination methods: When the current operating environment temperature of the refrigerant detection device is the temperature detected by the first temperature detection module of the indoor unit at a location within a set distance range from the refrigerant detection device, the first determination method is: within a preset first time period, determining the maximum value and the minimum value of the current operating environment temperature of the refrigerant detection device; determining the difference between the maximum value and the minimum value of the current operating environment temperature of the refrigerant detection device as the maximum temperature difference of the current operating environment temperature of the refrigerant detection device; when the current operating environment temperature of the refrigerant detection device is detected by the second temperature detection module of the indoor unit... In the case of the pipe temperature of the indoor heat exchanger of the indoor unit or the indoor ambient temperature of the indoor unit detected by the third temperature detection module of the indoor unit, the second determination method is as follows: within a preset first time period, determine the maximum value and the minimum value of the pipe temperature of the indoor heat exchanger of the indoor unit; and determine the difference between the maximum value and the minimum value of the pipe temperature of the indoor heat exchanger of the indoor unit, denoted as the first difference; within the preset first time period, determine the maximum value and the minimum value of the indoor ambient temperature of the indoor unit; and determine the difference between the maximum value and the minimum value of the indoor ambient temperature of the indoor unit, denoted as the second difference; the maximum value of the first difference and the second difference is taken as the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device.

[0012] In conjunction with the above method, another aspect of the present invention provides a control device for an air conditioner, wherein the indoor unit of the air conditioner has a refrigerant detection device; the refrigerant detection device is used to detect the refrigerant concentration at its own location, and record it as the current refrigerant concentration detected by the refrigerant detection device; the control device for the air conditioner includes: an acquisition unit configured to acquire the current refrigerant concentration detected by the refrigerant detection device after the air conditioner is powered on, provided that the refrigerant detection device itself is operational; and to acquire the current operating ambient temperature of the refrigerant detection device; and a control unit configured to determine that the current refrigerant concentration detected by the refrigerant detection device is... The control unit is further configured to, if it is determined that the current refrigerant concentration detected by the refrigerant detection device is less than the preset concentration threshold, control the air conditioner to maintain the current state of the air conditioner; the control unit is further configured to, if it is determined that the current refrigerant concentration detected by the refrigerant detection device is greater than or equal to the preset concentration threshold, determine whether the indoor unit has experienced refrigerant leakage by combining the current operating ambient temperature of the refrigerant detection device, the current state of the air conditioner, and the current refrigerant concentration detected by the refrigerant detection device; and, if it is determined that the indoor unit has experienced refrigerant leakage, control the air conditioner to execute a preset refrigerant leakage fault protection mechanism.

[0013] In some embodiments, the indoor unit further includes a temperature detection device; the temperature detection device includes at least one of the following: a first temperature detection module, a second temperature detection module, and a third temperature detection module; wherein, the first temperature detection module is used to detect the temperature at a location within a set distance range from the refrigerant detection device; the second temperature detection module is used to detect the pipe temperature of the indoor heat exchanger of the indoor unit; the third temperature detection module is used to detect the indoor ambient temperature of the indoor unit; the acquisition unit acquires the current operating ambient temperature of the refrigerant detection device, including any of the following acquisition methods: a first acquisition method: acquiring the temperature at a location within a set distance range from the refrigerant detection device detected by the first temperature detection module, and recording it as the current operating ambient temperature of the refrigerant detection device; a second acquisition method: acquiring the pipe temperature of the indoor heat exchanger of the indoor unit detected by the second temperature detection module, and acquiring the indoor ambient temperature of the indoor unit detected by the third temperature detection module; using the pipe temperature of the indoor heat exchanger of the indoor unit or the indoor ambient temperature of the indoor unit as the current operating ambient temperature of the refrigerant detection device.

[0014] In some implementations, the control unit determines whether the indoor unit has experienced a refrigerant leak by combining the current operating ambient temperature of the refrigerant detection device, the current state of the air conditioner, and the current refrigerant concentration detected by the refrigerant detection device. This includes: determining the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device within a preset first time period; and determining whether the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner; if the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device is less than the preset temperature threshold in the current target operating mode of the air conditioner, then determining that the indoor unit has experienced a refrigerant leak; if the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, then determining whether the indoor unit has experienced a refrigerant leak by combining the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device.

[0015] In some implementations, the control unit determines whether the indoor unit has experienced a refrigerant leak by combining the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device. This includes: determining whether the current state of the air conditioner is a preset off state or a preset running state; if the current state of the air conditioner is determined to be the off state, then determining that the indoor unit has experienced a refrigerant leak; if the current state of the air conditioner is determined to be the running state, then controlling the air conditioner to shut down, and then determining whether the indoor unit has experienced a refrigerant leak based on the current refrigerant concentration detected by the refrigerant detection device.

[0016] In some implementations, the control unit determines whether the indoor unit has experienced a refrigerant leak based on the current refrigerant concentration detected by the refrigerant detection device, including: determining whether the current refrigerant concentration detected by the refrigerant detection device continues to rise within a preset second time period; if it is determined that the current refrigerant concentration detected by the refrigerant detection device continues to rise within the preset second time period, then it is determined that the indoor unit has experienced a refrigerant leak; if it is determined that the current refrigerant concentration detected by the refrigerant detection device does not continue to rise within the preset second time period, then it is determined that the indoor unit has not experienced a refrigerant leak, and the control unit restarts and resumes operation.

[0017] In some embodiments, the control unit determines the maximum temperature difference of the current operating environment temperature of the refrigerant detection device within a preset first time period, including any of the following determination methods: When the current operating environment temperature of the refrigerant detection device is the temperature detected by the first temperature detection module of the indoor unit at a location within a set distance range from the refrigerant detection device, the control unit, in the case where the current operating environment temperature of the refrigerant detection device is determined by the temperature detected by the first temperature detection module of the indoor unit at a location within a set distance range from the refrigerant detection device, the first determination method is: within a preset first time period, determine the maximum value and the minimum value of the current operating environment temperature of the refrigerant detection device; determine the difference between the maximum value and the minimum value of the current operating environment temperature of the refrigerant detection device as the maximum temperature difference of the current operating environment temperature of the refrigerant detection device; the control unit, when the current operating environment temperature of the refrigerant detection device is determined by the second temperature detection module of the indoor unit... In the case of the pipe temperature of the indoor heat exchanger of the indoor unit detected by the temperature detection module or the indoor ambient temperature of the indoor unit detected by the third temperature detection module of the indoor unit, the second determination method is as follows: within a preset first time period, determine the maximum value and the minimum value of the pipe temperature of the indoor heat exchanger of the indoor unit; and determine the difference between the maximum value and the minimum value of the pipe temperature of the indoor heat exchanger of the indoor unit, denoted as the first difference; within the preset first time period, determine the maximum value and the minimum value of the indoor ambient temperature of the indoor unit; and determine the difference between the maximum value and the minimum value of the indoor ambient temperature of the indoor unit, denoted as the second difference; the maximum value of the first difference and the second difference is taken as the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device.

[0018] In conjunction with the above-described device, the present invention further provides an air conditioner, comprising: the control device for the air conditioner described above.

[0019] In conjunction with the above method, the present invention further provides a storage medium comprising a stored program, wherein, when the program is executed, the device on which the storage medium is located executes the steps of the control method for the air conditioner described above.

[0020] In conjunction with the above method, the present invention further provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the control method for the air conditioner described above.

[0021] Therefore, the solution of this invention involves installing a refrigerant sensor at a location within the air conditioning unit where refrigerant leakage may occur, and using a temperature sensor within a preset distance range of the refrigerant sensor to obtain the ambient temperature at the sensor's location (or using a temperature sensor from the indoor heat exchanger or the indoor unit's ambient temperature sensor to obtain the ambient temperature at the sensor's location). After the air conditioner is powered on, assuming the refrigerant sensor itself is functioning normally, the system combines the refrigerant concentration detected by the sensor with the ambient temperature at the sensor's location to determine whether a refrigerant leak has occurred. If a refrigerant leak is detected, the system will control the air conditioner to shut down for protection. Thus, by combining the refrigerant concentration detected by the sensor with the ambient temperature at the sensor's location, the system can accurately determine whether a refrigerant leak has occurred, avoiding false alarms caused by distortion of the refrigerant concentration detected by the sensor due to changes in the ambient temperature at the sensor's location. This improves the reliability of refrigerant leak protection and enhances the user experience.

[0022] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention.

[0023] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0024] Figure 1 This is a flowchart illustrating an embodiment of the control method for an air conditioner according to the present invention;

[0025] Figure 2 This is a schematic flowchart of an embodiment of the method of the present invention for determining whether a refrigerant leak has occurred by combining the current operating ambient temperature of the refrigerant detection device, the current state of the air conditioner, and the current refrigerant concentration detected by the refrigerant detection device;

[0026] Figure 3 This is a schematic flowchart of an embodiment of the method of the present invention for determining whether a refrigerant leak has occurred by combining the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device;

[0027] Figure 4 This is a flowchart illustrating an embodiment of the method of the present invention, which determines whether the indoor unit is leaking refrigerant based on the current refrigerant concentration detected by the refrigerant detection device.

[0028] Figure 5 This is a flowchart illustrating an embodiment of a first method for determining the maximum temperature difference of the current operating environment temperature of the refrigerant detection device in the method of the present invention.

[0029] Figure 6 This is a flowchart illustrating an embodiment of a second method for determining the maximum temperature difference of the current operating environment temperature of the refrigerant detection device in the method of the present invention.

[0030] Figure 7 This is a schematic diagram of the structure of an embodiment of the control device for an air conditioner according to the present invention;

[0031] Figure 8 This is a schematic flowchart of an embodiment of a refrigerant leakage protection and control method for an R32 combustible refrigerant air conditioner according to the present invention;

[0032] Figure 9 This is a schematic flowchart of another embodiment of a refrigerant leakage protection and control method for an R32 combustible refrigerant air conditioner according to the present invention.

[0033] Referring to the accompanying drawings, the reference numerals in the embodiments of the present invention are as follows:

[0034] 102 - Acquisition unit; 104 - Control unit. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0036] Considering that some solutions for detecting refrigerant leaks in air conditioners may produce false alarms even when there is no leak, for example, some solutions provide a refrigerant leak detection method where, when the refrigerant concentration detected by the air conditioner's refrigerant sensor is greater than a preset concentration, a preset process is performed to reduce the refrigerant concentration at the detection location where the refrigerant detection device is located; after performing the preset process, a second concentration detected by the refrigerant detection device is obtained; and a refrigerant leak is determined based on the second concentration.

[0037] Other solutions provide a method for detecting refrigerant leakage by obtaining the refrigerant concentration at a predetermined sampling point at a first moment and at a second moment, wherein the second moment is later than the first moment; obtaining the refrigerant concentration change rate based on the refrigerant concentration at the first moment, the refrigerant concentration at the second moment, and the first and second moments; and determining whether the refrigerant is leaking based on the refrigerant concentration change rate.

[0038] However, the above solutions are all based on the assumption that the refrigerant sensor can accurately detect the concentration without deviation. In actual use, the performance of the sensor in the refrigerant concentration detection instrument is affected by temperature. For some sensors based on physical principles, such as infrared sensors, temperature changes affect their ability to absorb and detect refrigerant molecules. At different temperatures, parameters such as the sensor's sensitivity and response time may change, leading to a deviation between the detected refrigerant concentration value and the actual value. Rapid temperature changes, such as evaporator frosting and defrosting, may also cause the sensor's detection temperature to change as described above. In this case, detection deviations may occur, leading to false alarms and leakage protection shutdowns.

[0039] Therefore, the present invention proposes a control method for an air conditioner, specifically a refrigerant leakage protection control method for an R32 combustible refrigerant air conditioner. Based on the concentration value detected by the refrigerant sensor, temperature detection is added to assist in confirming the accuracy of the concentration value detected by the refrigerant sensor. This avoids false alarms caused by sudden changes in the operating ambient temperature of the refrigerant sensor (i.e., the temperature near the refrigerant sensor) during evaporator frosting and defrosting, which can lead to distortion of the concentration detection value. This achieves reliable protection against refrigerant leakage in the R32 combustible refrigerant air conditioner and improves the user experience.

[0040] According to embodiments of the present invention, a control method for an air conditioner is provided, such as... Figure 1 The diagram illustrates a flowchart of an embodiment of the method of the present invention. The indoor unit of the air conditioner includes a refrigerant detection device, such as a refrigerant sensor. The refrigerant detection device is used to detect the refrigerant concentration at its own location, recorded as the current refrigerant concentration detected by the device. The refrigerant detection device is positioned within the indoor unit at a location where all potential leak points (such as locations where refrigerant leaks may occur) can be easily detected, for example, at pipe welding points or 90° bends in the pipes. In the solution of the present invention, as... Figure 1 As shown, the control method of the air conditioner includes steps S110 to S140.

[0041] In step S110, after the air conditioner is powered on, and assuming the refrigerant detection device is functional, the current refrigerant concentration detected by the refrigerant detection device is acquired; and the current operating ambient temperature of the refrigerant detection device is acquired. The current refrigerant concentration detected by the refrigerant detection device is, for example, the refrigerant concentration v detected by the refrigerant sensor; the current operating ambient temperature of the refrigerant detection device is the ambient temperature at the location of the refrigerant detection device itself, for example: by setting a temperature sensor within a preset distance range of the refrigerant sensor to acquire the operating ambient temperature at the location of the refrigerant sensor, or by using a temperature sensor from the indoor heat exchanger or an indoor ambient temperature sensor from the indoor unit to acquire the operating ambient temperature at the location of the refrigerant sensor. The refrigerant detection device itself being functional means that the refrigerant detection device is functioning normally.

[0042] In step S120, it is determined whether the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold. The preset concentration threshold, such as a preset concentration value va, is between 10% and 15% of the refrigerant concentration LFL.

[0043] In step S130, if it is determined that the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the air conditioner is controlled to maintain its current state.

[0044] In step S140, if it is determined that the current refrigerant concentration detected by the refrigerant detection device is greater than or equal to a preset concentration threshold, then, based on the current operating ambient temperature of the refrigerant detection device, the current state of the air conditioner, and the current refrigerant concentration detected by the refrigerant detection device, it is determined whether the indoor unit has experienced a refrigerant leak; and, if it is determined that the indoor unit has experienced a refrigerant leak, then the air conditioner is controlled to execute a preset refrigerant leak fault protection mechanism, such as determining that the air conditioner has experienced a refrigerant leak fault and causing the air conditioner to shut down for protection. Of course, if it is determined that the indoor unit has not experienced a refrigerant leak, then the air conditioner is controlled to maintain its current state.

[0045] The present invention addresses the problem that when refrigerant sensors operate in air conditioning units, rapid changes in ambient temperature at the sensor location due to frosting and defrosting can cause deviations in the sensor's detection values, leading to false alarms and leak protection shutdowns. It provides a refrigerant leak protection control scheme for R32 flammable refrigerant air conditioners. By combining the refrigerant concentration value detected by the sensor with the change in ambient temperature at the sensor's location, it accurately determines whether a refrigerant leak has occurred. This avoids the influence of unit operating parameters on the refrigerant sensor's detection values ​​during air conditioner use, offering the advantage of reliable detection results and providing reliable protection against refrigerant leaks in R32 flammable refrigerant air conditioners.

[0046] In some embodiments, the indoor unit further includes a temperature detection device, such as a temperature sensor; the temperature detection device includes at least one of the following: a first temperature detection module, a second temperature detection module, and a third temperature detection module; wherein, the first temperature detection module, such as a temperature sensor disposed at a position within a set distance range from the refrigerant detection device, is used to detect the temperature at the position within the set distance range from the refrigerant detection device; the second temperature detection module, such as a temperature sensor disposed at the indoor heat exchanger of the indoor unit, is used to detect the pipe temperature of the indoor heat exchanger of the indoor unit; the third temperature detection module, such as a temperature sensor disposed on the indoor unit, is used to detect the indoor ambient temperature of the indoor unit.

[0047] In step S110, the current operating ambient temperature of the refrigerant detection device is obtained, including any of the following methods: the first method and the second method.

[0048] The first method of acquisition is to acquire the temperature at a location within a set distance range from the refrigerant detection device, as detected by the first temperature detection module, and record it as the current operating environment temperature of the refrigerant detection device.

[0049] In this invention, the indoor unit of the air conditioner is equipped with a temperature detection device and a refrigerant concentration detection device. The refrigerant concentration detection device is generally a refrigerant sensor, primarily used to detect the refrigerant concentration at the sensor's location. The refrigerant sensor is preferably located in a position within the air conditioner where refrigerant leaks are likely to occur, such as evaporator elbow weld points, 90° bends in pipes, or locations with thinner pipe walls. Simultaneously, a temperature sensor is placed near the refrigerant sensor to detect the ambient temperature at its location. This avoids false alarms caused by sudden changes in ambient temperature leading to distorted concentration readings, thus providing reliable protection against refrigerant leaks in R32 flammable refrigerant air conditioners and improving user experience. The "near the refrigerant sensor" refers to a location relatively close to the sensor, where surrounding airflow allows for the detection of the ambient temperature at the sensor's location.

[0050] The second method of obtaining the refrigerant temperature is as follows: the pipe temperature of the indoor heat exchanger of the indoor unit is obtained by the second temperature detection module, and the indoor ambient temperature of the indoor unit is obtained by the third temperature detection module; the pipe temperature of the indoor heat exchanger or the indoor ambient temperature of the indoor unit is used as the current operating ambient temperature of the refrigerant detection device.

[0051] In the solution of this invention, if the refrigerant sensor is close to the temperature sensor of the indoor heat exchanger or the indoor ambient temperature sensor, the indoor heat exchanger temperature sensor and the indoor ambient temperature sensor can be used directly for judgment. In this case, Max(ΔT1,ΔT2) can be used instead of ΔT, where ΔT1 is the maximum temperature difference of the indoor heat exchanger within time t1, and ΔT2 is the maximum temperature difference of the indoor ambient temperature within time t1. The main purpose is to determine whether the operating temperature of the refrigerant sensor has changed. Changes in the evaporator temperature will not cause changes in the operating temperature of the refrigerant sensor, thus preventing detection failure and false alarms.

[0052] In some embodiments, the specific process of determining whether the indoor unit has experienced refrigerant leakage in step S140, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, is based on the current operating ambient temperature of the refrigerant detection device, the current state of the air conditioner, and the current refrigerant concentration detected by the refrigerant detection device. See the following exemplary description.

[0053] The following is combined Figure 2 The illustrated flowchart shows an embodiment of the method of the present invention, which combines the current operating ambient temperature of the refrigerant detection device, the current state of the air conditioner, and the current refrigerant concentration detected by the refrigerant detection device to determine whether a refrigerant leak has occurred. The flowchart further explains the specific process of determining whether a refrigerant leak has occurred in step S140 by combining the current operating ambient temperature of the refrigerant detection device, the current state of the air conditioner, and the current refrigerant concentration detected by the refrigerant detection device, including steps S210 to S230.

[0054] Step S210: If the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, within a preset first time period, determine the maximum temperature difference of the current operating environment temperature of the refrigerant detection device; and determine whether the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner. The current target operating mode of the air conditioner is, for example, heating mode or cooling mode. The preset temperature threshold in the current target operating mode of the air conditioner is, for example, a preset temperature value K; for example, a preset temperature threshold of 5°C when the current target operating mode is cooling mode, and a preset temperature threshold of 10°C when the current target operating mode is heating mode.

[0055] Step S220: If the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, and if it is determined that the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is less than the preset temperature threshold in the current target operating mode of the air conditioner, then it is determined that the indoor unit has a refrigerant leak.

[0056] Step S230: If the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, and if it is determined that the maximum temperature difference of the current working environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, then, in combination with the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device, it is determined whether the indoor unit has experienced refrigerant leakage.

[0057] Existing solutions rely on temperature sensors to detect evaporator or condenser temperatures to determine system operating status. This is primarily based on the premise that refrigerant leakage leads to decreased cooling performance and differences in pipe temperature compared to when there is no leakage. However, in actual unit operation, besides refrigerant leakage, other non-leakage conditions such as excessively long connecting pipes or system blockages can also cause the same phenomenon, making differentiation difficult. The solution of this invention, while still primarily based on the concentration value detected by the refrigerant sensor, adds temperature detection to further verify the accuracy of the detected concentration value. This avoids false alarms caused by sudden changes in the refrigerant sensor's operating environment temperature (i.e., the temperature near the refrigerant sensor) during evaporator frosting and defrosting, resulting in distorted concentration detection values. This provides reliable protection against refrigerant leakage in R32 flammable refrigerant air conditioners, improving the user experience.

[0058] In some implementations, the specific process of determining whether the indoor unit has experienced refrigerant leakage in step S230, in the case where the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold and the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, is combined with the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device. See the following exemplary description.

[0059] The following is combined Figure 3 The schematic diagram of an embodiment of the method of the present invention, which combines the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device to determine whether a refrigerant leak has occurred, further illustrates the specific process of determining whether a refrigerant leak has occurred in step S230, which combines the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device, including steps S310 to S330.

[0060] Step S310: If the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, and the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner, determine whether the current state of the air conditioner is a preset shutdown state or a preset operating state. The preset shutdown state refers to the compressor shutdown state, including states such as shutdown and compressor shutdown upon reaching the temperature point; the preset operating state refers to the compressor operating state, including modes such as cooling, dehumidification, and heating.

[0061] Step S320: If the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, and the maximum temperature difference of the current working environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, then if it is determined that the current state of the air conditioner is the shutdown state, then it is determined that the indoor unit has a refrigerant leak.

[0062] Step S330: If the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, and the maximum temperature difference of the current working environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, if it is determined that the current state of the air conditioner is the operating state, then the air conditioner is controlled to stop. Then, based on the current refrigerant concentration detected by the refrigerant detection device, it is determined whether the indoor unit has experienced refrigerant leakage.

[0063] In the solution of this invention, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, and the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device are combined to determine whether the indoor unit has experienced refrigerant leakage. Thus, based on the judgment based on the concentration value detected by the refrigerant sensor, temperature detection is added to assist in confirming the accuracy of the concentration value detected by the refrigerant sensor, avoiding false alarms caused by the distortion of the concentration detection value due to sudden changes in the operating environment temperature of the refrigerant sensor (i.e., the temperature near the refrigerant sensor), thereby achieving reliable protection against refrigerant leakage in R32 combustible refrigerant air conditioners and improving the user experience.

[0064] In some implementations, the specific process of determining whether the indoor unit has experienced refrigerant leakage based on the current refrigerant concentration detected by the refrigerant detection device after controlling the air conditioner to stop in step S330, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, and the current state of the air conditioner is the operating state, is described in the following exemplary description.

[0065] The following is combined Figure 4 The illustrated flowchart shows an embodiment of the method of the present invention to determine whether the indoor unit has experienced refrigerant leakage based on the current refrigerant concentration detected by the refrigerant detection device. The specific process of determining whether the indoor unit has experienced refrigerant leakage based on the current refrigerant concentration detected by the refrigerant detection device in step S330 is further explained, including steps S410 to S430.

[0066] Step S410: If the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the maximum temperature difference of the current working environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, and the current state of the air conditioner is the operating state, after controlling the air conditioner to stop, determine whether the current refrigerant concentration detected by the refrigerant detection device continues to rise within a preset second time period.

[0067] Step S420: If the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the maximum temperature difference of the current working environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, and the current state of the air conditioner is the operating state, after controlling the air conditioner to stop, if it is determined that the current refrigerant concentration detected by the refrigerant detection device continues to rise within a preset second time period, then it is determined that the indoor unit has a refrigerant leak.

[0068] Step S430: If the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, and the current state of the air conditioner is the operating state, after controlling the air conditioner to stop, if it is determined that the current refrigerant concentration detected by the refrigerant detection device does not continue to rise within a preset second time period, it is determined that the indoor unit has not experienced refrigerant leakage. The air conditioner is then restarted and resumed operation. Specifically, the air conditioner is restarted and restored to the operating state of the air conditioner before it was controlled to stop. Then, the process returns to continue determining whether the current refrigerant concentration detected by the refrigerant detection device is less than the preset concentration threshold, thereby cyclically determining whether the indoor unit has experienced refrigerant leakage.

[0069] In the solution of this invention, after controlling the air conditioner to stop when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the maximum temperature difference of the current working environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, and the current state of the air conditioner is the operating state, the system determines whether the indoor unit has experienced refrigerant leakage based on the current refrigerant concentration detected by the refrigerant detection device. Therefore, in addition to judging based on the concentration value detected by the refrigerant sensor, temperature detection is added to assist in confirming the accuracy of the concentration value detected by the refrigerant sensor. This avoids false alarms caused by distortion of the concentration detection value due to sudden changes in the working environment temperature of the refrigerant sensor (i.e., the temperature near the refrigerant sensor), thus achieving reliable protection against refrigerant leakage in R32 combustible refrigerant air conditioners and improving the user experience.

[0070] In some implementations, in step S210, if the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is determined within a preset first time period, including any of the following determination methods: the first determination method and the second determination method.

[0071] The first method of determination is as follows: when the current operating ambient temperature of the refrigerant detection device is the temperature at a location within a set distance range from the refrigerant detection device detected by the first temperature detection module of the indoor unit, the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device is determined within a preset first time period.

[0072] The following is combined Figure 5The flowchart shown is a first embodiment of the method of the present invention for determining the maximum temperature difference of the current working environment temperature of the refrigerant detection device. The specific process of determining the maximum temperature difference of the current working environment temperature of the refrigerant detection device in step S210 is further explained, including steps S510 to S520.

[0073] Step S510: Within a preset first time period, determine the maximum value of the current operating environment temperature of the refrigerant detection device and the minimum value of the current operating environment temperature of the refrigerant detection device.

[0074] Step S520: Determine the difference between the maximum value of the current operating ambient temperature of the refrigerant detection device and the minimum value of the current operating ambient temperature of the refrigerant detection device, and use this difference as the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device.

[0075] Figure 8 This is a schematic flowchart illustrating an embodiment of a refrigerant leakage protection and control method for an R32 combustible refrigerant air conditioner according to the present invention. Figure 8 As shown, the refrigerant leakage protection and control method for R32 combustible refrigerant air conditioners includes:

[0076] Step 11: After powering on the unit, first determine if the refrigerant sensor is working properly. If yes, proceed to step 12; otherwise, consider the refrigerant sensor to have reached the end of its lifespan and trigger an alarm, requiring replacement. For example, if the refrigerant sensor has communication problems or has reached the end of its lifespan and is not working, an alarm will be triggered directly requesting replacement. Specifically, determining if the refrigerant sensor is working properly can include: checking if the refrigerant sensor can detect the refrigerant concentration upon power-on, and checking if the refrigerant sensor and indoor unit can exchange data normally, etc.

[0077] Step 12: With the refrigerant sensor operating normally, the sensor begins to monitor the refrigerant concentration v in real time and determines whether the detected concentration v is lower than the preset concentration value va. If yes, the unit maintains its current state; otherwise, proceed to step 13 to begin refrigerant leak detection and processing. When the refrigerant concentration v detected by the sensor is lower than the preset concentration value va, the unit operates normally; when the refrigerant concentration v detected by the sensor is higher than the preset concentration value va, refrigerant leak detection and processing begins.

[0078] The preset concentration value va is a program-preset concentration value. Considering that the unit needs to activate protection before the refrigerant concentration LFL (lower flammability limit) reaches 25%, and also taking the time t2 required for the refrigerant leak detection process, the preset concentration value va is generally set between 10% and 15% of the refrigerant concentration LFL. The reason for setting the preset concentration value va to between 10% and 15% of the refrigerant concentration LFL is that after the refrigerant concentration v reaches the preset concentration value va, it still takes t2 time before a leak fault is detected; therefore, the refrigerant concentration before protection cannot exceed 25%.

[0079] Step 13: When the refrigerant concentration v detected by the refrigerant sensor is higher than the preset concentration value va, the refrigerant leak detection process begins. Specifically, it checks whether the maximum temperature difference ΔT detected within time t1 is greater than or equal to the preset temperature value K. If yes, proceed to step 14; otherwise, a refrigerant leak fault is detected, and the unit is shut down for protection. Here, t1 is the preset time, typically around 1 minute considering the temperature detection lag and the timeliness of refrigerant leak protection; ΔT is the maximum difference detected by the temperature sensor within time t1, i.e., the difference between the maximum and minimum values ​​detected within time t1; and K is the preset temperature value, generally around 5℃ for cooling and around 10℃ for heating.

[0080] In step 13, the refrigerant leak detection process is as follows: First, the temperature change before the refrigerant concentration v detected by the refrigerant sensor reaches the preset concentration value va is judged. When the maximum temperature difference ΔT detected within time t1 is less than the preset temperature value K, it is determined that the operating temperature has no effect on the concentration value detected by the refrigerant sensor. At this time, it is directly judged that there is a refrigerant leak, and all loads of the whole unit are handled according to the refrigerant leak protection. Among them, the common practice for handling all loads of the whole unit according to the refrigerant leak protection is to shut down all outdoor unit loads, close the electronic expansion valve that supplies refrigerant to the room, etc.; set the indoor unit fan speed to the highest and the air guide plate to the smoothest position to disperse the refrigerant in the room. If the refrigerant concentration v detected by the refrigerant sensor reaches the refrigerant leak judgment standard, and at the same time, since the operating temperature of the refrigerant sensor does not change suddenly, it is judged that the detected concentration value is not problematic. Combined, it is judged that a refrigerant leak has occurred.

[0081] Step 14: When the maximum temperature difference ΔT detected within time t1 is greater than or equal to the preset temperature value K, it is determined that the operating temperature of the unit may affect the concentration value detected by the refrigerant sensor (i.e., the refrigerant concentration v detected by the refrigerant sensor). At this time, it is determined whether the unit is in operation: if not, proceed to step 15; if so, proceed to step 16.

[0082] Step 15: If the unit is in a stopped state at this time (i.e., the compressor is stopped), it is directly judged that there is a refrigerant leak, and all loads of the whole unit are handled according to the refrigerant leak protection.

[0083] Step 16: If the unit is running at this time, it is determined that the refrigerant concentration v detected by the refrigerant sensor may have a detection error. In this case, the unit is first shut down, and then it is checked whether the refrigerant concentration v detected by the refrigerant sensor will continue to rise within t2 hours after shutdown. If not, proceed to step 17; if yes, proceed to step 18. During t2 hours, the current concentration value v is detected in real time and compared with the previously detected concentration value v'. If v < v', it is determined that there is no continuous rise; if v < v' does not occur within t2 hours, it is determined that there is a continuous rise.

[0084] Step 17: If the refrigerant concentration v detected by the refrigerant sensor does not continuously increase within time t2 after shutdown, the unit resumes its previous operating state and then returns to step 12 for cyclic detection.

[0085] Step 18: If the refrigerant concentration v detected by the refrigerant sensor continues to rise within t2 after the machine stops, it is determined to be a refrigerant leak, and all loads of the whole machine shall be handled in accordance with the refrigerant leak protection.

[0086] In this invention, a refrigerant sensor is used to detect the refrigerant concentration near the indoor evaporator, and an indoor temperature sensor is used to detect the temperature change of the indoor heat exchanger to determine the accuracy of the refrigerant concentration detection value. This increases the accuracy of refrigerant leak detection and avoids temperature field changes near the refrigerant sensor caused by evaporator freezing or defrosting during air conditioner use, which could lead to concentration detection deviations and false protection. This achieves reliable protection against refrigerant leaks in R32 combustible refrigerant air conditioners and improves user experience.

[0087] The second determination method is as follows: when the current operating ambient temperature of the refrigerant detection device is the pipe temperature of the indoor heat exchanger of the indoor unit detected by the second temperature detection module of the indoor unit or the indoor ambient temperature of the indoor unit detected by the third temperature detection module of the indoor unit, the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device is determined within a preset first time period.

[0088] The following is combined Figure 6 The flowchart shown is a second embodiment of the method of the present invention for determining the maximum temperature difference of the current working environment temperature of the refrigerant detection device. It further illustrates the specific process of determining the maximum temperature difference of the current working environment temperature of the refrigerant detection device in step S120, including steps S610 to S630.

[0089] Step S610: Within a preset first time period, determine the maximum value of the pipe temperature of the indoor heat exchanger of the indoor unit and the minimum value of the pipe temperature of the indoor heat exchanger of the indoor unit; and determine the difference between the maximum value of the pipe temperature of the indoor heat exchanger of the indoor unit and the minimum value of the pipe temperature of the indoor heat exchanger of the indoor unit, and record it as the first difference.

[0090] Step S620: Within a preset first time period, determine the maximum value and the minimum value of the indoor ambient temperature of the indoor unit; and determine the difference between the maximum value and the minimum value of the indoor ambient temperature of the indoor unit, denoted as the second difference.

[0091] Step S630: The maximum value between the first difference and the second difference is taken as the maximum temperature difference of the current working environment temperature of the refrigerant detection device.

[0092] Figure 9 This is a schematic flowchart illustrating another embodiment of a refrigerant leakage protection and control method for an R32 combustible refrigerant air conditioner according to the present invention. Figure 9 As shown, the refrigerant leakage protection and control method for R32 combustible refrigerant air conditioners includes:

[0093] Step 21: After powering on the unit, first determine if the refrigerant sensor is working properly. If yes, proceed to step 22; otherwise, consider the refrigerant sensor to have reached the end of its lifespan and trigger an alarm, requiring replacement. For example, if the refrigerant sensor has communication problems or has reached the end of its lifespan and is not working, an alarm will be triggered directly requesting replacement. Specifically, determining if the refrigerant sensor is working properly can include: checking if the refrigerant sensor can detect the refrigerant concentration upon power-on, and checking if the refrigerant sensor and the indoor unit can exchange data normally, etc.

[0094] Step 22: Under normal operating conditions, the refrigerant sensor begins to detect the refrigerant concentration v in real time and determines whether the detected refrigerant concentration v is lower than the preset concentration value va. If yes, the unit maintains its current state; otherwise, proceed to step 23 to begin refrigerant leak detection and processing. When the refrigerant concentration v detected by the refrigerant sensor is lower than the preset concentration value va, the unit operates normally; when the refrigerant concentration v detected by the refrigerant sensor is higher than the preset concentration value va, refrigerant leak detection and processing begins.

[0095] The preset concentration value va is a program-preset concentration value. Considering that the unit needs to activate protection before the refrigerant concentration LFL (lower flammability limit) reaches 25%, and also taking the time t2 required for the refrigerant leak detection process, the preset concentration value va is generally set between 10% and 15% of the refrigerant concentration LFL. The reason for setting the preset concentration value va to between 10% and 15% of the refrigerant concentration LFL is that after the refrigerant concentration v reaches the preset concentration value va, it still takes t2 time before a leak fault is detected; therefore, the refrigerant concentration before protection cannot exceed 25%.

[0096] Step 23: When the refrigerant concentration v detected by the refrigerant sensor is higher than the preset concentration value va, the refrigerant leak detection process begins. Specifically, it checks whether the maximum temperature difference MAX(ΔT1, ΔT2) detected within time t1 is greater than or equal to the preset temperature value K. If yes, proceed to step 24; otherwise, a refrigerant leak fault is detected, and the unit is shut down for protection. Here, t1 is the preset time, typically around 1 minute considering the temperature detection lag and the need for timely refrigerant leak protection; MAX(ΔT1, ΔT2) is the maximum difference detected by the temperature sensor within time t1, i.e., the difference between the maximum and minimum detected values ​​within time t1; and K is the preset temperature value, generally around 5℃ for cooling and around 10℃ for heating.

[0097] In step 23, the refrigerant leak detection process is as follows: First, the temperature change before the refrigerant concentration v detected by the refrigerant sensor reaches the preset concentration value va is judged. When the maximum temperature difference MAX(ΔT1,ΔT2) detected within time t1 is less than the preset temperature value K, it is determined that the operating temperature has no effect on the concentration value detected by the refrigerant sensor. At this time, it is directly judged that there is a refrigerant leak, and all loads of the whole unit are handled according to the refrigerant leak protection. Among them, the common practice for handling all loads of the whole unit according to the refrigerant leak protection is to shut down all outdoor unit loads, close the electronic expansion valve that supplies refrigerant to the room, etc.; set the indoor unit fan speed to the highest and the air guide plate to the smoothest position to disperse the refrigerant in the room. If the refrigerant concentration v detected by the refrigerant sensor reaches the refrigerant leak judgment standard, and at the same time, since the operating temperature of the refrigerant sensor does not change suddenly, it is judged that the detected concentration value is not problematic. Combined, it is judged that a refrigerant leak has occurred.

[0098] Step 24: When the maximum temperature difference MAX(ΔT1,ΔT2) detected within time t1 is greater than or equal to the preset temperature value K, it is determined that the operating temperature of the unit may affect the concentration value detected by the refrigerant sensor (i.e., the refrigerant concentration v detected by the refrigerant sensor). At this time, it is determined whether the unit is in operation: if not, proceed to step 25; if yes, proceed to step 26.

[0099] Step 25: If the unit is in a stopped state at this time (i.e., the compressor is stopped), it is directly judged that there is a refrigerant leak, and all loads of the whole unit are handled according to the refrigerant leak protection.

[0100] Step 26: If the unit is running at this time, it is determined that the refrigerant concentration v detected by the refrigerant sensor may have a detection deviation. At this time, the unit is shut down first, and then it is checked whether the refrigerant concentration v detected by the refrigerant sensor will continue to rise within t2 after shutdown. If not, proceed to step 27; if yes, proceed to step 28.

[0101] Step 27: If the refrigerant concentration v detected by the refrigerant sensor does not continuously increase within time t2 after shutdown, the unit resumes its previous operating state and then returns to step 22 for cyclic detection.

[0102] Step 28: If the refrigerant concentration v detected by the refrigerant sensor continues to rise within t2 after the machine stops, it is determined to be a refrigerant leak, and all loads of the whole machine shall be handled in accordance with the refrigerant leak protection.

[0103] In this invention, a refrigerant leak is determined by combining the refrigerant concentration value detected by the refrigerant sensor with the indoor evaporator temperature and the indoor ambient temperature. By detecting the indoor ambient temperature and the evaporator temperature, detection errors caused by rapid changes in evaporator temperature can be eliminated, achieving reliable protection against refrigerant leaks in R32 flammable refrigerant air conditioners and improving the user experience.

[0104] The technical solution of this embodiment involves installing a refrigerant sensor at a potential refrigerant leak location within the air conditioning unit. A temperature sensor is positioned within a preset distance range of the refrigerant sensor to obtain the ambient temperature at the sensor's location (or a temperature sensor from the indoor heat exchanger or the indoor unit's ambient temperature sensor can be used to obtain the ambient temperature at the sensor's location). After the air conditioner is powered on, assuming the refrigerant sensor itself is functioning normally, the system combines the refrigerant concentration detected by the sensor with the ambient temperature at the sensor's location to determine if a refrigerant leak has occurred. If a leak is detected, the air conditioner is shut down for protection. Therefore, by combining the refrigerant concentration detected by the sensor with the ambient temperature at the sensor's location, the system can accurately determine if a refrigerant leak has occurred, avoiding false alarms caused by distortion of the detected refrigerant concentration due to changes in the ambient temperature at the sensor's location. This improves the reliability of refrigerant leak protection and enhances the user experience.

[0105] According to an embodiment of the present invention, a control device for an air conditioner corresponding to the control method for an air conditioner is also provided. See also Figure 7The diagram shows a structural schematic of an embodiment of the device of the present invention. The indoor unit of the air conditioner has a refrigerant detection device, such as a refrigerant sensor; the refrigerant detection device is used to detect the refrigerant concentration at its own location, and this concentration is recorded as the current refrigerant concentration detected by the refrigerant detection device; the refrigerant detection device is located in the indoor unit at a location where all potential leak points (such as locations where refrigerant leaks may occur) can be easily detected, such as pipe welding points, pipe 90° bends, etc.; in the solution of the present invention, such as... Figure 7 As shown, the control device of the air conditioner includes: an acquisition unit 102 and a control unit 104.

[0106] The acquisition unit 102 is configured to, after the air conditioner is powered on and assuming the refrigerant detection device is operational, acquire the current refrigerant concentration detected by the refrigerant detection device; and acquire the current operating ambient temperature of the refrigerant detection device. The current refrigerant concentration detected by the refrigerant detection device is, for example, the refrigerant concentration v detected by the refrigerant sensor. The current operating ambient temperature of the refrigerant detection device is the ambient temperature at the location of the refrigerant detection device itself. For example, a temperature sensor can be set within a preset distance range of the refrigerant sensor to acquire the operating ambient temperature at the location of the refrigerant sensor, or a temperature sensor from the indoor heat exchanger or an indoor ambient temperature sensor from the indoor unit can be used to acquire the operating ambient temperature at the location of the refrigerant sensor. The specific functions and processing of this acquisition unit 102 are described in step S110.

[0107] The control unit 104 is configured to determine whether the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold; wherein, the preset concentration threshold, such as a preset concentration value va, is between 10% and 15% of the refrigerant concentration LFL. The specific functions and processing of the control unit 104 are described in step S120.

[0108] The control unit 104 is further configured to control the air conditioner to maintain its current state if it is determined that the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold. The specific functions and processing of the control unit 104 are further described in step S130.

[0109] The control unit 104 is further configured to, if it is determined that the current refrigerant concentration detected by the refrigerant detection device is greater than or equal to a preset concentration threshold, determine whether the indoor unit has experienced a refrigerant leak by combining the current operating ambient temperature of the refrigerant detection device, the current state of the air conditioner, and the current refrigerant concentration detected by the refrigerant detection device; and, if it is determined that the indoor unit has experienced a refrigerant leak, control the air conditioner to execute a preset refrigerant leak fault protection mechanism, such as causing the air conditioner to shut down for protection if a refrigerant leak fault is determined to have occurred. Of course, the control unit 104 is also configured to, if it is determined that the indoor unit has not experienced a refrigerant leak, control the air conditioner to maintain its current state. The specific functions and processing of this control unit 104 are further described in step S140.

[0110] The present invention addresses the problem that when refrigerant sensors operate in air conditioning units, rapid changes in ambient temperature at the sensor location due to frosting and defrosting can cause deviations in the sensor's detection values, leading to false alarms and leak protection shutdowns. It provides a refrigerant leak protection control scheme for R32 flammable refrigerant air conditioners. By combining the refrigerant concentration value detected by the sensor with the change in ambient temperature at the sensor's location, it accurately determines whether a refrigerant leak has occurred. This avoids the influence of unit operating parameters on the refrigerant sensor's detection values ​​during air conditioner use, offering the advantage of reliable detection results and providing reliable protection against refrigerant leaks in R32 flammable refrigerant air conditioners.

[0111] In some embodiments, the indoor unit further includes a temperature detection device, such as a temperature sensor; the temperature detection device includes at least one of the following: a first temperature detection module, a second temperature detection module, and a third temperature detection module.

[0112] The first temperature detection module, such as a temperature sensor located at a position within a set distance range from the refrigerant detection device, is used to detect the temperature at a position within the set distance range from the refrigerant detection device.

[0113] The second temperature detection module, such as a temperature sensor installed at the indoor heat exchanger of the indoor unit, is used to detect the pipe temperature of the indoor heat exchanger of the indoor unit.

[0114] The third temperature detection module, such as a temperature sensor installed on the indoor unit, is used to detect the indoor ambient temperature of the indoor unit.

[0115] The acquisition unit 102 acquires the current operating ambient temperature of the refrigerant detection device, including any of the following acquisition methods: the first acquisition method and the second acquisition method.

[0116] The first acquisition method: The acquisition unit 102 is further configured to acquire the temperature at a location within a set distance range from the refrigerant detection device detected by the first temperature detection module, and record it as the current working environment temperature of the refrigerant detection device.

[0117] In this invention, the indoor unit of the air conditioner is equipped with a temperature detection device and a refrigerant concentration detection device. The refrigerant concentration detection device is generally a refrigerant sensor, primarily used to detect the refrigerant concentration at the sensor's location. The refrigerant sensor is preferably located in a position within the air conditioner where refrigerant leakage is likely to occur. Simultaneously, a temperature sensor is placed near the refrigerant sensor to detect the ambient temperature at its location, preventing false alarms caused by sudden changes in ambient temperature leading to distorted concentration readings. This achieves reliable protection against refrigerant leakage in R32 flammable refrigerant air conditioners, improving user experience. The "near the refrigerant sensor" refers to a location close to the sensor where air circulation allows for the detection of the ambient temperature at the sensor's location.

[0118] The second acquisition method: The acquisition unit 102 is further configured to acquire the pipe temperature of the indoor heat exchanger of the indoor unit detected by the second temperature detection module, and acquire the indoor ambient temperature of the indoor unit detected by the third temperature detection module; and use the pipe temperature of the indoor heat exchanger of the indoor unit or the indoor ambient temperature of the indoor unit as the current operating ambient temperature of the refrigerant detection device.

[0119] In the solution of this invention, if the refrigerant sensor is close to the temperature sensor of the indoor heat exchanger or the indoor ambient temperature sensor, the indoor heat exchanger temperature sensor and the indoor ambient temperature sensor can be used directly for judgment. In this case, Max(ΔT1,ΔT2) can be used instead of ΔT, where ΔT1 is the maximum temperature difference of the indoor heat exchanger within time t1, and ΔT2 is the maximum temperature difference of the indoor ambient temperature within time t1. The main purpose is to determine whether the operating temperature of the refrigerant sensor has changed. Changes in the evaporator temperature will not cause changes in the operating temperature of the refrigerant sensor, thus preventing detection failure and false alarms.

[0120] In some embodiments, the control unit 104, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, determines whether the indoor unit has experienced a refrigerant leak by combining the current operating ambient temperature of the refrigerant detection device, the current state of the air conditioner, and the current refrigerant concentration detected by the refrigerant detection device, including:

[0121] The control unit 104 is further configured to, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, determine, within a preset first time period, the maximum temperature difference of the current operating environment temperature of the refrigerant detection device; and determine whether the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner. The preset temperature threshold in the current target operating mode of the air conditioner is, for example, a program-preset temperature value K; the preset temperature threshold is, for example, 5°C when the current target operating mode is cooling mode, and 10°C when the current target operating mode is heating mode. The specific functions and processing of this control unit 104 are further described in step S210.

[0122] The control unit 104 is further configured to, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, determine that the indoor unit has experienced a refrigerant leak if the maximum temperature difference between the current operating ambient temperature of the refrigerant detection device and the current target operating mode of the air conditioner is less than a preset temperature threshold. The specific functions and processing of this control unit 104 are further described in step S220.

[0123] The control unit 104 is further configured to, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, if it is determined that the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner, then, in conjunction with the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device, determine whether the indoor unit has experienced a refrigerant leak. The specific functions and processing of this control unit 104 are further described in step S230.

[0124] Existing solutions rely on temperature sensors to detect evaporator or condenser temperatures to determine system operating status. This is primarily based on the premise that refrigerant leakage leads to decreased cooling performance and differences in pipe temperature compared to when there is no leakage. However, in actual unit operation, besides refrigerant leakage, other non-leakage conditions such as excessively long connecting pipes or system blockages can also cause the same phenomenon, making differentiation difficult. The solution of this invention, while still primarily based on the concentration value detected by the refrigerant sensor, adds temperature detection to further verify the accuracy of the detected concentration value. This avoids false alarms caused by sudden changes in the refrigerant sensor's operating environment temperature (i.e., the temperature near the refrigerant sensor) during evaporator frosting and defrosting, resulting in distorted concentration detection values. This provides reliable protection against refrigerant leakage in R32 flammable refrigerant air conditioners, improving the user experience.

[0125] In some embodiments, the control unit 104, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, and the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner, determines whether the indoor unit has experienced a refrigerant leak by combining the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device, including:

[0126] The control unit 104 is further configured to determine whether the current state of the air conditioner is a preset shutdown state or a preset operating state when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, and the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner. The specific functions and processing of this control unit 104 are further described in step S310.

[0127] The control unit 104 is further configured to, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, and the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner, determine that the indoor unit has experienced a refrigerant leak if it is determined that the current state of the air conditioner is the shutdown state. The specific functions and processing of this control unit 104 are further described in step S320.

[0128] The control unit 104 is further configured to, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, and the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner, if it is determined that the current state of the air conditioner is the operating state, then control the air conditioner to stop, and then determine whether the indoor unit has experienced refrigerant leakage based on the current refrigerant concentration detected by the refrigerant detection device. The specific functions and processing of this control unit 104 are also described in step S330.

[0129] In the solution of this invention, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, and the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device are combined to determine whether the indoor unit has experienced refrigerant leakage. Thus, based on the judgment based on the concentration value detected by the refrigerant sensor, temperature detection is added to assist in confirming the accuracy of the concentration value detected by the refrigerant sensor, avoiding false alarms caused by the distortion of the concentration detection value due to sudden changes in the operating environment temperature of the refrigerant sensor (i.e., the temperature near the refrigerant sensor), thereby achieving reliable protection against refrigerant leakage in R32 combustible refrigerant air conditioners and improving the user experience.

[0130] In some embodiments, the control unit 104, after controlling the air conditioner to stop when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner, and the current state of the air conditioner is the operating state, determines whether the indoor unit has experienced refrigerant leakage based on the current refrigerant concentration detected by the refrigerant detection device, including:

[0131] The control unit 104 is further configured to, after controlling the air conditioner to stop, determine whether the current refrigerant concentration detected by the refrigerant detection device continues to rise within a preset second time period when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner, and the current state of the air conditioner is the operating state. The specific functions and processing of this control unit 104 are also described in step S410.

[0132] The control unit 104 is further configured to, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner, and the current state of the air conditioner is the operating state, after controlling the air conditioner to stop, if it is determined that the current refrigerant concentration detected by the refrigerant detection device continues to rise within a preset second time period, then it is determined that the indoor unit has experienced a refrigerant leak. The specific functions and processing of this control unit 104 are also described in step S420.

[0133] The control unit 104 is further configured to, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the maximum temperature difference of the current operating environment temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner, and the current state of the air conditioner is the operating state, after controlling the air conditioner to stop, if it is determined that the current refrigerant concentration detected by the refrigerant detection device has not continued to rise within a preset second time period, then it is determined that the indoor unit has not experienced refrigerant leakage, and the air conditioner is controlled to restart and resume operation. Specifically, the air conditioner is controlled to restart and restore to the operating state of the air conditioner before it was controlled to stop, and then returns to the previous state to continue to determine whether the current refrigerant concentration detected by the refrigerant detection device is less than the preset concentration threshold, thereby cyclically determining whether the indoor unit has experienced refrigerant leakage. The specific functions and processing of this control unit 104 are also described in step S430.

[0134] In the solution of this invention, after controlling the air conditioner to stop when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the maximum temperature difference of the current working environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, and the current state of the air conditioner is the operating state, the system determines whether the indoor unit has experienced refrigerant leakage based on the current refrigerant concentration detected by the refrigerant detection device. Therefore, in addition to judging based on the concentration value detected by the refrigerant sensor, temperature detection is added to assist in confirming the accuracy of the concentration value detected by the refrigerant sensor. This avoids false alarms caused by distortion of the concentration detection value due to sudden changes in the working environment temperature of the refrigerant sensor (i.e., the temperature near the refrigerant sensor), thus achieving reliable protection against refrigerant leakage in R32 combustible refrigerant air conditioners and improving the user experience.

[0135] In some embodiments, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the control unit 104 determines the maximum temperature difference of the current operating environment temperature of the refrigerant detection device within a preset first time period, including any of the following determination methods: the first determination method and the second determination method.

[0136] When the current operating ambient temperature of the refrigerant detection device is the temperature at a location within a set distance range from the refrigerant detection device detected by the first temperature detection module of the indoor unit, the control unit 104 determines the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device within a preset first time period, i.e., the first determination method:

[0137] The control unit 104 is further configured to determine the maximum value and the minimum value of the current operating ambient temperature of the refrigerant detection device within a preset first time period. The specific functions and processing of the control unit 104 are further described in step S510.

[0138] The control unit 104 is further configured to determine the difference between the maximum value of the current operating ambient temperature of the refrigerant detection device and the minimum value of the current operating ambient temperature of the refrigerant detection device, as the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device. The specific functions and processing of the control unit 104 are further described in step S520.

[0139] Figure 8 This is a schematic flowchart illustrating an embodiment of a refrigerant leakage protection and control method for an R32 combustible refrigerant air conditioner according to the present invention. Figure 8 As shown, the refrigerant leakage protection and control method for R32 combustible refrigerant air conditioners includes:

[0140] Step 11: After powering on the unit, first determine if the refrigerant sensor is working properly. If yes, proceed to step 12; otherwise, consider the refrigerant sensor to have reached the end of its lifespan and trigger an alarm, requiring replacement. For example, if the refrigerant sensor has communication problems or has reached the end of its lifespan and is not working, an alarm will be triggered directly requesting replacement. Specifically, determining if the refrigerant sensor is working properly can include: checking if the refrigerant sensor can detect the refrigerant concentration upon power-on, and checking if the refrigerant sensor and indoor unit can exchange data normally, etc.

[0141] Step 12: With the refrigerant sensor operating normally, the sensor begins to monitor the refrigerant concentration v in real time and determines whether the detected concentration v is lower than the preset concentration value va. If yes, the unit maintains its current state; otherwise, proceed to step 13 to begin refrigerant leak detection and processing. When the refrigerant concentration v detected by the sensor is lower than the preset concentration value va, the unit operates normally; when the refrigerant concentration v detected by the sensor is higher than the preset concentration value va, refrigerant leak detection and processing begins.

[0142] The preset concentration value va is a program-preset concentration value. Considering that the unit needs to activate protection before the refrigerant concentration LFL (lower flammability limit) reaches 25%, and also taking the time t2 required for the refrigerant leak detection process, the preset concentration value va is generally set between 10% and 15% of the refrigerant concentration LFL. The reason for setting the preset concentration value va to between 10% and 15% of the refrigerant concentration LFL is that after the refrigerant concentration v reaches the preset concentration value va, it still takes t2 time before a leak fault is detected; therefore, the refrigerant concentration before protection cannot exceed 25%.

[0143] Step 13: When the refrigerant concentration v detected by the refrigerant sensor is higher than the preset concentration value va, the refrigerant leak detection process begins. Specifically, it checks whether the maximum temperature difference ΔT detected within time t1 is greater than or equal to the preset temperature value K. If yes, proceed to step 14; otherwise, a refrigerant leak fault is detected, and the unit is shut down for protection. Here, t1 is the preset time, typically around 1 minute considering the temperature detection lag and the timeliness of refrigerant leak protection; ΔT is the maximum difference detected by the temperature sensor within time t1, i.e., the difference between the maximum and minimum values ​​detected within time t1; and K is the preset temperature value, generally around 5℃ for cooling and around 10℃ for heating.

[0144] In step 13, the refrigerant leak detection process is as follows: First, the temperature change before the refrigerant concentration v detected by the refrigerant sensor reaches the preset concentration value va is judged. When the maximum temperature difference ΔT detected within time t1 is less than the preset temperature value K, it is determined that the operating temperature has no effect on the concentration value detected by the refrigerant sensor. At this time, it is directly judged that there is a refrigerant leak, and all loads of the whole unit are handled according to the refrigerant leak protection. Among them, the common practice for handling all loads of the whole unit according to the refrigerant leak protection is to shut down all outdoor unit loads, close the electronic expansion valve that supplies refrigerant to the room, etc.; set the indoor unit fan speed to the highest and the air guide plate to the smoothest position to disperse the refrigerant in the room. If the refrigerant concentration v detected by the refrigerant sensor reaches the refrigerant leak judgment standard, and at the same time, since the operating temperature of the refrigerant sensor does not change suddenly, it is judged that the detected concentration value is not problematic. Combined, it is judged that a refrigerant leak has occurred.

[0145] Step 14: When the maximum temperature difference ΔT detected within time t1 is greater than or equal to the preset temperature value K, it is determined that the operating temperature of the unit may affect the concentration value detected by the refrigerant sensor (i.e., the refrigerant concentration v detected by the refrigerant sensor). At this time, it is determined whether the unit is in operation: if not, proceed to step 15; if so, proceed to step 16.

[0146] Step 15: If the unit is in a stopped state at this time (i.e., the compressor is stopped), it is directly judged that there is a refrigerant leak, and all loads of the whole unit are handled according to the refrigerant leak protection.

[0147] Step 16: If the unit is running at this time, it is determined that the refrigerant concentration v detected by the refrigerant sensor may have a detection deviation. At this time, the unit is shut down first, and then it is checked whether the refrigerant concentration v detected by the refrigerant sensor will continue to rise within t2 after shutdown. If not, proceed to step 17; if yes, proceed to step 18.

[0148] Step 17: If the refrigerant concentration v detected by the refrigerant sensor does not continuously increase within time t2 after shutdown, the unit resumes its previous operating state and then returns to step 12 for cyclic detection.

[0149] Step 18: If the refrigerant concentration v detected by the refrigerant sensor continues to rise within t2 after the machine stops, it is determined to be a refrigerant leak, and all loads of the whole machine shall be handled in accordance with the refrigerant leak protection.

[0150] In this invention, a refrigerant sensor is used to detect the refrigerant concentration near the indoor evaporator, and an indoor temperature sensor is used to detect the temperature change of the indoor heat exchanger to determine the accuracy of the refrigerant concentration detection value. This increases the accuracy of refrigerant leak detection and avoids temperature field changes near the refrigerant sensor caused by evaporator freezing or defrosting during air conditioner use, which could lead to concentration detection deviations and false protection. This achieves reliable protection against refrigerant leaks in R32 combustible refrigerant air conditioners and improves user experience.

[0151] The control unit 104, when the current operating ambient temperature of the refrigerant detection device is determined by either the pipe temperature of the indoor heat exchanger of the indoor unit detected by the second temperature detection module of the indoor unit or the indoor ambient temperature of the indoor unit detected by the third temperature detection module of the indoor unit, determines the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device within a preset first time period, i.e., the second determination method:

[0152] The control unit 104 is further configured to determine, within a preset first time period, the maximum value and the minimum value of the pipe temperature of the indoor heat exchanger of the indoor unit; and to determine the difference between the maximum value and the minimum value of the pipe temperature of the indoor heat exchanger of the indoor unit, denoted as the first difference. The specific functions and processing of this control unit 104 are further described in step S610.

[0153] The control unit 104 is further configured to determine, within a preset first time period, the maximum value and the minimum value of the indoor ambient temperature of the indoor unit; and to determine the difference between the maximum value and the minimum value of the indoor ambient temperature of the indoor unit, denoted as a second difference. The specific functions and processing of this control unit 104 are further described in step S620.

[0154] The control unit 104 is further configured to use the maximum value between the first difference and the second difference as the maximum temperature difference of the current operating environment temperature of the refrigerant detection device. The specific functions and processing of the control unit 104 are further described in step S630.

[0155] Figure 9 This is a schematic flowchart illustrating another embodiment of a refrigerant leakage protection and control method for an R32 combustible refrigerant air conditioner according to the present invention. Figure 9As shown, the refrigerant leakage protection and control method for R32 combustible refrigerant air conditioners includes:

[0156] Step 21: After powering on the unit, first determine if the refrigerant sensor is working properly. If yes, proceed to step 22; otherwise, consider the refrigerant sensor to have reached the end of its lifespan and trigger an alarm, requiring replacement. For example, if the refrigerant sensor has communication problems or has reached the end of its lifespan and is not working, an alarm will be triggered directly requesting replacement. Specifically, determining if the refrigerant sensor is working properly can include: checking if the refrigerant sensor can detect the refrigerant concentration upon power-on, and checking if the refrigerant sensor and the indoor unit can exchange data normally, etc.

[0157] Step 22: Under normal operating conditions, the refrigerant sensor begins to detect the refrigerant concentration v in real time and determines whether the detected refrigerant concentration v is lower than the preset concentration value va. If yes, the unit maintains its current state; otherwise, proceed to step 23 to begin refrigerant leak detection and processing. When the refrigerant concentration v detected by the refrigerant sensor is lower than the preset concentration value va, the unit operates normally; when the refrigerant concentration v detected by the refrigerant sensor is higher than the preset concentration value va, refrigerant leak detection and processing begins.

[0158] The preset concentration value va is a program-preset concentration value. Considering that the unit needs to activate protection before the refrigerant concentration LFL (lower flammability limit) reaches 25%, and also taking the time t2 required for the refrigerant leak detection process, the preset concentration value va is generally set between 10% and 15% of the refrigerant concentration LFL. The reason for setting the preset concentration value va to between 10% and 15% of the refrigerant concentration LFL is that after the refrigerant concentration v reaches the preset concentration value va, it still takes t2 time before a leak fault is detected; therefore, the refrigerant concentration before protection cannot exceed 25%.

[0159] Step 23: When the refrigerant concentration v detected by the refrigerant sensor is higher than the preset concentration value va, the refrigerant leak detection process begins. Specifically, it checks whether the maximum temperature difference MAX(ΔT1, ΔT2) detected within time t1 is greater than or equal to the preset temperature value K. If yes, proceed to step 24; otherwise, a refrigerant leak fault is detected, and the unit is shut down for protection. Here, t1 is the preset time, typically around 1 minute considering the temperature detection lag and the need for timely refrigerant leak protection; MAX(ΔT1, ΔT2) is the maximum difference detected by the temperature sensor within time t1, i.e., the difference between the maximum and minimum detected values ​​within time t1; and K is the preset temperature value, generally around 5℃ for cooling and around 10℃ for heating.

[0160] In step 23, the refrigerant leak detection process is as follows: First, the temperature change before the refrigerant concentration v detected by the refrigerant sensor reaches the preset concentration value va is judged. When the maximum temperature difference MAX(ΔT1,ΔT2) detected within time t1 is less than the preset temperature value K, it is determined that the operating temperature has no effect on the concentration value detected by the refrigerant sensor. At this time, it is directly judged that there is a refrigerant leak, and all loads of the whole unit are handled according to the refrigerant leak protection. Among them, the common practice for handling all loads of the whole unit according to the refrigerant leak protection is to shut down all outdoor unit loads, close the electronic expansion valve that supplies refrigerant to the room, etc.; set the indoor unit fan speed to the highest and the air guide plate to the smoothest position to disperse the refrigerant in the room. If the refrigerant concentration v detected by the refrigerant sensor reaches the refrigerant leak judgment standard, and at the same time, since the operating temperature of the refrigerant sensor does not change suddenly, it is judged that the detected concentration value is not problematic. Combined, it is judged that a refrigerant leak has occurred.

[0161] Step 24: When the maximum temperature difference MAX(ΔT1,ΔT2) detected within time t1 is greater than or equal to the preset temperature value K, it is determined that the operating temperature of the unit may affect the concentration value detected by the refrigerant sensor (i.e., the refrigerant concentration v detected by the refrigerant sensor). At this time, it is determined whether the unit is in operation: if not, proceed to step 25; if yes, proceed to step 26.

[0162] Step 25: If the unit is in a stopped state at this time (i.e., the compressor is stopped), it is directly judged that there is a refrigerant leak, and all loads of the whole unit are handled according to the refrigerant leak protection.

[0163] Step 26: If the unit is running at this time, it is determined that the refrigerant concentration v detected by the refrigerant sensor may have a detection deviation. At this time, the unit is shut down first, and then it is checked whether the refrigerant concentration v detected by the refrigerant sensor will continue to rise within t2 after shutdown. If not, proceed to step 27; if yes, proceed to step 28.

[0164] Step 27: If the refrigerant concentration v detected by the refrigerant sensor does not continuously increase within time t2 after shutdown, the unit resumes its previous operating state and then returns to step 22 for cyclic detection.

[0165] Step 28: If the refrigerant concentration v detected by the refrigerant sensor continues to rise within t2 after the machine stops, it is determined to be a refrigerant leak, and all loads of the whole machine shall be handled in accordance with the refrigerant leak protection.

[0166] In this invention, a refrigerant leak is determined by combining the refrigerant concentration value detected by the refrigerant sensor with the indoor evaporator temperature and the indoor ambient temperature. By detecting the indoor ambient temperature and the evaporator temperature, detection errors caused by rapid changes in evaporator temperature can be eliminated, achieving reliable protection against refrigerant leaks in R32 flammable refrigerant air conditioners and improving the user experience.

[0167] Since the processing and functions implemented by the device in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned methods, any details not covered in the description of this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0168] According to an embodiment of the present invention, an air conditioner corresponding to a control device for an air conditioner is also provided. This air conditioner may include the control device for an air conditioner described above.

[0169] Since the processing and functions implemented by the air conditioner in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned devices, any details not covered in the description of this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0170] According to an embodiment of the present invention, a computer program product corresponding to the control method for an air conditioner is also provided, comprising a computer program that, when executed by a processor, implements the steps of the control method for an air conditioner described above.

[0171] Since the processing and functions implemented by the product in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned methods, any details not covered in the description of this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0172] According to an embodiment of the present invention, a storage medium corresponding to a control method for an air conditioner is also provided, the storage medium including a stored program, wherein, when the program is executed, the device where the storage medium is located executes the steps of the control method for the air conditioner described above.

[0173] Since the processing and functions implemented by the storage medium in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned methods, any details not covered in this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0174] In summary, it is readily understood by those skilled in the art that, without conflict, the aforementioned advantageous methods can be freely combined and superimposed.

[0175] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A control method for an air conditioner, characterized in that, The indoor unit of the air conditioner has a refrigerant detection device; the refrigerant detection device is used to detect the refrigerant concentration at its own location, and the concentration is recorded as the current refrigerant concentration detected by the refrigerant detection device. The control method for the air conditioner includes: After the air conditioner is powered on, and assuming the refrigerant detection device is capable of operating, the current refrigerant concentration detected by the refrigerant detection device is obtained; and the current operating ambient temperature of the refrigerant detection device is obtained. Determine whether the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold; If it is determined that the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, then the air conditioner is controlled to maintain its current state. If the refrigerant concentration detected by the refrigerant detection device is greater than or equal to a preset concentration threshold, then, in conjunction with the current operating ambient temperature of the refrigerant detection device, the current state of the air conditioner, and the current refrigerant concentration detected by the refrigerant detection device, it is determined whether the indoor unit has experienced a refrigerant leak. This includes: determining the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device within a preset first time period; and determining whether the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold in the current target operating mode of the air conditioner; if the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device is less than the preset temperature threshold in the current target operating mode of the air conditioner, then it is determined that the indoor unit has experienced a refrigerant leak; if the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operating mode of the air conditioner, then, in conjunction with the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device, it is determined whether the indoor unit has experienced a refrigerant leak; and, if it is determined that the indoor unit has experienced a refrigerant leak, then the air conditioner is controlled to execute a preset refrigerant leak fault protection mechanism.

2. The control method for an air conditioner according to claim 1, characterized in that, The indoor unit also includes a temperature detection device; the temperature detection device includes at least one of the following: a first temperature detection module, a second temperature detection module, and a third temperature detection module; wherein, The first temperature detection module is used to detect the temperature at a location within a set distance range from the refrigerant detection device; The second temperature detection module is used to detect the pipe temperature of the indoor heat exchanger of the indoor unit; The third temperature detection module is used to detect the indoor ambient temperature of the indoor unit; The current operating ambient temperature of the refrigerant detection device can be obtained using any of the following methods: The first method of acquisition: the temperature at a location within a set distance range from the refrigerant detection device detected by the first temperature detection module is recorded as the current operating ambient temperature of the refrigerant detection device; The second method of obtaining the refrigerant temperature is as follows: the pipe temperature of the indoor heat exchanger of the indoor unit is obtained by the second temperature detection module, and the indoor ambient temperature of the indoor unit is obtained by the third temperature detection module; the pipe temperature of the indoor heat exchanger or the indoor ambient temperature of the indoor unit is used as the current operating ambient temperature of the refrigerant detection device.

3. The control method for an air conditioner according to claim 1, characterized in that, Based on the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device, determine whether the indoor unit is leaking refrigerant, including: Determine whether the current state of the air conditioner is a preset shutdown state or a preset running state; If it is determined that the current state of the air conditioner is the off state, then it is determined that the indoor unit has a refrigerant leak; If it is determined that the current state of the air conditioner is the operating state, the air conditioner is controlled to stop. Then, based on the current refrigerant concentration detected by the refrigerant detection device, it is determined whether the indoor unit has experienced a refrigerant leak.

4. The control method for an air conditioner according to claim 3, characterized in that, Based on the current refrigerant concentration detected by the refrigerant detection device, determine whether the indoor unit is leaking refrigerant, including: Determine whether the current refrigerant concentration detected by the refrigerant detection device continues to rise within a preset second time period; If it is determined that the current refrigerant concentration detected by the refrigerant detection device continues to rise within a preset second time period, then it is determined that the indoor unit has experienced a refrigerant leak. If it is determined that the current refrigerant concentration detected by the refrigerant detection device does not continue to rise within the preset second time period, it is determined that there is no refrigerant leak in the indoor unit, and the air conditioner is controlled to restart and resume operation.

5. The control method for an air conditioner according to any one of claims 1 to 4, characterized in that, Within a preset first time period, determine the maximum temperature difference of the current operating environment temperature of the refrigerant detection device, including any of the following determination methods: When the current operating ambient temperature of the refrigerant detection device is the temperature detected by the first temperature detection module of the indoor unit at a location within a set distance range from the refrigerant detection device, the first determination method is as follows: Within a preset first time period, determine the maximum value of the current operating ambient temperature of the refrigerant detection device and the minimum value of the current operating ambient temperature of the refrigerant detection device; The difference between the maximum value of the current operating ambient temperature of the refrigerant detection device and the minimum value of the current operating ambient temperature of the refrigerant detection device is determined as the maximum temperature difference of the current operating ambient temperature of the refrigerant detection device. The second determination method is as follows: When the current operating ambient temperature of the refrigerant detection device is determined by either the pipe temperature of the indoor heat exchanger detected by the second temperature detection module of the indoor unit or the indoor ambient temperature detected by the third temperature detection module of the indoor unit. Within a preset first time period, determine the maximum value and the minimum value of the pipe temperature of the indoor heat exchanger of the indoor unit; and determine the difference between the maximum value and the minimum value of the pipe temperature of the indoor heat exchanger of the indoor unit, denoted as the first difference. Within a preset first time period, determine the maximum value of the indoor ambient temperature of the indoor unit and the minimum value of the indoor ambient temperature of the indoor unit. The difference between the maximum value of the indoor ambient temperature of the indoor unit and the minimum value of the indoor ambient temperature of the indoor unit is determined and denoted as the second difference. The maximum value between the first difference and the second difference is taken as the maximum temperature difference of the current operating environment temperature of the refrigerant detection device.

6. A control device for an air conditioner that uses the control method for an air conditioner as described in claim 1 to control the air conditioner, characterized in that, The indoor unit of the air conditioner has a refrigerant detection device; the refrigerant detection device is used to detect the refrigerant concentration at its own location, and the concentration is recorded as the current refrigerant concentration detected by the refrigerant detection device. The control device for the air conditioner includes: The acquisition unit is configured to acquire the current refrigerant concentration detected by the refrigerant detection device after the air conditioner is powered on, provided that the refrigerant detection device itself is capable of operating; and to acquire the current operating ambient temperature of the refrigerant detection device. The control unit is configured to determine whether the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold. The control unit is further configured to control the air conditioner to maintain its current state if it is determined that the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold. The control unit is further configured to, if it is determined that the current refrigerant concentration detected by the refrigerant detection device is greater than or equal to a preset concentration threshold, determine whether the indoor unit has experienced a refrigerant leak by combining the current operating ambient temperature of the refrigerant detection device, the current state of the air conditioner, and the current refrigerant concentration detected by the refrigerant detection device; and, if it is determined that the indoor unit has experienced a refrigerant leak, control the air conditioner to execute a preset refrigerant leak fault protection mechanism.

7. An air conditioner, characterized in that, include: The control device for an air conditioner as described in claim 6.

8. A storage medium, characterized in that, The storage medium includes a stored program, wherein, when the program is executed, the device containing the storage medium is controlled to perform the control method of the air conditioner according to any one of claims 1 to 5.

9. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the control method for the air conditioner according to any one of claims 1 to 5.

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