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

Abstract

The invention discloses an air conditioner and a control method and device thereof, a storage medium and a computer program product. The method comprises the steps that after the air conditioner is powered on, under the condition that a refrigerant detection device can work, whether the current refrigerant concentration detected by the refrigerant detection device is smaller than a preset concentration threshold value or not is determined; if it is determined that the current refrigerant concentration detected by the refrigerant detection device is smaller than the preset concentration threshold value, whether refrigerant leakage happens to the indoor unit or not is determined by 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; and if it is determined that refrigerant leakage occurs in the indoor unit, the air conditioner is controlled to execute a preset refrigerant leakage fault protection mechanism. According to the scheme, by combining the refrigerant concentration detected by the refrigerant sensor and the working environment temperature of the position where the refrigerant sensor is located, whether refrigerant leakage happens to the air conditioner or not is accurately judged, false alarm is avoided, and the reliability of refrigerant leakage protection is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of air conditioners, and specifically relates to a control method, device, air conditioner, storage medium and computer program product of an air conditioner, and in particular to a refrigerant leakage protection control method, device, air conditioner, storage medium and computer program product of an R32 flammable refrigerant air conditioner. Background Art

[0002] R32 refrigerant is increasingly used in air conditioners. Refrigerant leakage will not only significantly reduce the cooling or heating performance of the air conditioner, causing the indoor temperature to fail to meet the set requirements, affecting the user's comfort, but also poses a safety hazard. Especially for multi-split units, since a single outdoor unit is paired with multiple indoor units, the room area used by a single indoor unit is small, and in order to ensure the effect of all indoor units, the outdoor unit has a larger amount of refrigerant than a one-to-one model. Since the outdoor unit and all indoor units are the same system, when an indoor unit leaks, all outdoor unit refrigerants will leak to the leak point, and the refrigerant will gather in the same room, which can easily cause the refrigerant concentration to reach the lower limit of the flammable concentration of R32 refrigerant LFL (i.e., the ignition lower limit), and even cause problems such as fire and explosion. Therefore, it is crucial to detect whether the refrigerant is leaking.

[0003] However, the detection methods for whether the air conditioner refrigerant is leaking in related solutions are often not sensitive enough. There may be a situation where there is no leakage but a false alarm occurs, causing the leakage protection to shut down, affecting the user experience.

[0004] The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are prior art. Summary of the invention

[0005] The object of the present invention is to provide a control method, device, air conditioner, storage medium and computer program product for an air conditioner, so as to solve the problem in related schemes that when detecting whether the refrigerant of the air conditioner is leaking, there is a false alarm when there is no leakage, resulting in leakage protection shutdown, which affects the user experience. By combining the refrigerant concentration detected by the refrigerant sensor and the working environment temperature at the location of the refrigerant sensor, it is possible to accurately determine whether the air conditioner has a refrigerant leakage, avoid false alarms caused by distortion of the refrigerant concentration detected by the refrigerant sensor due to changes in the working environment temperature at the location of the refrigerant sensor, improve the reliability of the refrigerant leakage protection, and improve the user experience.

[0006] The present invention provides a control method for an air conditioner, wherein the indoor unit of the air conditioner is provided with a refrigerant detection device; the refrigerant detection device is used to detect the refrigerant concentration at the position where the refrigerant detection device itself is located, which is recorded as the current refrigerant concentration detected by the refrigerant detection device; the control method for the air conditioner comprises: after the air conditioner is powered on, when the refrigerant detection device itself can work, obtaining the current refrigerant concentration detected by the refrigerant detection device; and obtaining the current working environment 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 the current state of the air conditioner; 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 a refrigerant leak in combination with 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; and if it is determined that the indoor unit has a refrigerant leak, controlling the air conditioner to execute a preset refrigerant leakage fault protection mechanism.

[0007] In some embodiments, the indoor unit further has 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 position 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 working ambient temperature of the refrigerant detection device includes any one of the following acquisition methods: a first acquisition method: obtaining the temperature at a position within a set distance range from the refrigerant detection device detected by the first temperature detection module, recorded as the current working ambient temperature of the refrigerant detection device; a second acquisition 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; taking the pipe temperature of the indoor heat exchanger of the indoor unit or the indoor ambient temperature of the indoor unit as the current working ambient temperature of the refrigerant detection device.

[0008] In some embodiments, in combination with 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, determining whether a refrigerant leakage occurs in the indoor unit includes: determining the maximum temperature difference of the current working environment temperature of the refrigerant detection device within a preset first time; and determining whether 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 value under the current target operating mode of the air conditioner; if it is determined that the maximum temperature difference of the current working environment temperature of the refrigerant detection device is less than the preset temperature threshold value under the current target operating mode of the air conditioner, determining that a refrigerant leakage occurs in the indoor unit; 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 value under 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, determining whether a refrigerant leakage occurs in the indoor unit.

[0009] In some embodiments, in combination with the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device, determining whether a refrigerant leakage occurs in the indoor unit includes: determining whether the current state of the air conditioner is a preset shutdown state or a preset operating state; if it is determined that the current state of the air conditioner is the shutdown state, determining that a refrigerant leakage occurs in the indoor unit; if it is determined that the current state of the air conditioner is the operating state, controlling the air conditioner to shut down, and then determining whether a refrigerant leakage occurs in the indoor unit based on the current refrigerant concentration detected by the refrigerant detection device.

[0010] In some embodiments, determining whether a refrigerant leakage occurs in the indoor unit is 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; if it is determined that the current refrigerant concentration detected by the refrigerant detection device continues to rise within the preset second time, then determining that a refrigerant leakage occurs in the indoor unit; 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, then determining that no refrigerant leakage occurs in the indoor unit, and controlling the air conditioner to restart and resume operation.

[0011] In some embodiments, within a preset first time, the maximum temperature difference of the current working environment temperature of the refrigerant detection device is determined, including any one of the following determination methods: when the current working environment temperature of the refrigerant detection device is the temperature at a position within a set distance range from the refrigerant detection device detected by the first temperature detection module of the indoor unit, the first determination method: within the preset first time, determine the maximum value of the current working environment temperature of the refrigerant detection device and the minimum value of the current working environment temperature of the refrigerant detection device; determine the difference between the maximum value of the current working environment temperature of the refrigerant detection device and the minimum value of the current working environment temperature of the refrigerant detection device as the maximum temperature difference of the current working environment temperature of the refrigerant detection device; when the current working environment temperature of the refrigerant detection device is the temperature detected by the second temperature detection module of the indoor unit, In the case of the tube 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: within a preset first time, determine the maximum value of the tube temperature of the indoor heat exchanger of the indoor unit and the minimum value of the tube temperature of the indoor heat exchanger of the indoor unit; and determine the difference between the maximum value of the tube temperature of the indoor heat exchanger of the indoor unit and the minimum value of the tube temperature of the indoor heat exchanger of the indoor unit, which is recorded as a first difference; within the preset first time, 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; and determine 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, which is recorded as a second difference; and use the maximum value of the first difference and the second difference as the maximum temperature difference of the current working ambient temperature of the refrigerant detection device.

[0012] Matching the above method, the present invention provides a control device for an air conditioner on the other hand, 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 the location of the refrigerant detection device itself, which is recorded as the current refrigerant concentration detected by the refrigerant detection device; the control device of the air conditioner includes: an acquisition unit, which is configured to acquire the current refrigerant concentration detected by the refrigerant detection device after the air conditioner is powered on and when the refrigerant detection device itself is able to work; and acquire the current working environment temperature of the refrigerant detection device; a control unit is configured to determine whether 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 a refrigerant leakage occurs in the indoor unit in combination with 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; and, if it is determined that a refrigerant leakage occurs in the indoor unit, control the air conditioner to execute a preset refrigerant leakage fault protection mechanism.

[0013] In some embodiments, the indoor unit further has 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 position 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 working ambient temperature of the refrigerant detection device, including any of the following acquisition methods: a first acquisition method: acquiring the temperature at a position within a set distance range from the refrigerant detection device detected by the first temperature detection module, recorded as the current working 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; taking the pipe temperature of the indoor heat exchanger of the indoor unit or the indoor ambient temperature of the indoor unit as the current working ambient temperature of the refrigerant detection device.

[0014] In some embodiments, the control unit determines whether a refrigerant leakage occurs in the indoor unit in combination with 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, including: determining the maximum temperature difference of the current working environment temperature of the refrigerant detection device within a preset first time; and determining whether 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 value under the current target operating mode of the air conditioner; if it is determined that the maximum temperature difference of the current working environment temperature of the refrigerant detection device is less than the preset temperature threshold value under the current target operating mode of the air conditioner, it is determined that a refrigerant leakage occurs in the indoor unit; 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 value under 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 a refrigerant leakage occurs in the indoor unit.

[0015] In some embodiments, the control unit, in combination with the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device, determines whether a refrigerant leakage occurs in the indoor unit, including: determining whether the current state of the air conditioner is a preset shutdown state or a preset operating state; if it is determined that the current state of the air conditioner is the shutdown state, determining that a refrigerant leakage occurs in the indoor unit; if it is determined that the current state of the air conditioner is the operating state, controlling the air conditioner to shut down, and then determining whether a refrigerant leakage occurs in the indoor unit based on the current refrigerant concentration detected by the refrigerant detection device.

[0016] In some embodiments, the control unit determines whether a refrigerant leakage occurs in the indoor unit 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; if it is determined that the current refrigerant concentration detected by the refrigerant detection device continues to rise within the preset second time, then it is determined that a refrigerant leakage occurs in the indoor unit; 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, then it is determined that no refrigerant leakage occurs in the indoor unit, and the air conditioner is controlled to restart and resume operation.

[0017] In some embodiments, the control unit determines the maximum temperature difference of the current working environment temperature of the refrigerant detection device within a preset first time, including any one of the following determination methods: the control unit, when the current working environment temperature of the refrigerant detection device is the temperature at a position within a set distance range from the refrigerant detection device detected by the first temperature detection module of the indoor unit, the first determination method: within the preset first time, determine the maximum value of the current working environment temperature of the refrigerant detection device and the minimum value of the current working environment temperature of the refrigerant detection device; determine the difference between the maximum value of the current working environment temperature of the refrigerant detection device and the minimum value of the current working environment temperature of the refrigerant detection device as the maximum temperature difference of the current working environment temperature of the refrigerant detection device; the control unit, when the current working environment temperature of the refrigerant detection device is the temperature detected by the second temperature detection module of the indoor unit In the case of the tube 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: within a preset first time, determine the maximum value of the tube temperature of the indoor heat exchanger of the indoor unit and the minimum value of the tube temperature of the indoor heat exchanger of the indoor unit; and determine the difference between the maximum value of the tube temperature of the indoor heat exchanger of the indoor unit and the minimum value of the tube temperature of the indoor heat exchanger of the indoor unit, which is recorded as a first difference; within the preset first time, 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; and determine 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, which is recorded as a second difference; and use the maximum value of the first difference and the second difference as the maximum temperature difference of the current working ambient temperature of the refrigerant detection device.

[0018] Matching the above device, the present invention provides an air conditioner on another aspect, including: the control device of the air conditioner described above.

[0019] Matching the above method, the present invention provides a storage medium on another aspect, wherein the storage medium includes a stored program, wherein when the program is running, the device where the storage medium is located is controlled to execute the steps of the air conditioner control method described above.

[0020] Matching the above method, the present invention further provides a computer program product on the other hand, including a computer program, which implements the steps of the above air conditioner control method when executed by a processor.

[0021] Therefore, the scheme of the present invention sets a refrigerant sensor at a position where refrigerant leakage may occur in the air-conditioning unit, and sets a temperature sensor within a preset distance range of the refrigerant sensor to obtain the working environment temperature at the position where the refrigerant sensor is located (or uses the temperature sensor of the indoor heat exchanger or the indoor environment temperature sensor of the indoor unit to obtain the working environment temperature at the position where the refrigerant sensor is located); after the air conditioner is powered on, if the refrigerant sensor itself can work normally, combined with the refrigerant concentration detected by the refrigerant sensor and the working environment temperature at the position where the refrigerant sensor is located, it is determined whether the air conditioner has a refrigerant leakage, and the air conditioner is controlled to shut down for protection when a refrigerant leakage occurs; thereby, by combining the refrigerant concentration detected by the refrigerant sensor and the working environment temperature at the position where the refrigerant sensor is located, it is possible to accurately determine whether the air conditioner has a refrigerant leakage, avoid false alarms caused by distortion of the refrigerant concentration detected by the refrigerant sensor due to changes in the working environment temperature at the position where the refrigerant sensor is located, improve the reliability of refrigerant leakage protection, and improve user experience.

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

[0023] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of a flow chart of an embodiment of a method for controlling an air conditioner of the present invention;

[0025] Figure 2 A flow chart of an embodiment of the method of the present invention for determining whether a refrigerant leakage occurs by 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;

[0026] Figure 3 A flow chart of an embodiment of the method of the present invention for determining whether a refrigerant leakage occurs by combining the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device;

[0027] Figure 4 A flow chart of an embodiment of the method of the present invention for determining whether a refrigerant leak occurs in the indoor unit according to the current refrigerant concentration detected by the refrigerant detection device;

[0028] Figure 5 A schematic flow chart of an embodiment of a first determination method for determining the maximum temperature difference of the current working environment temperature of the refrigerant detection device in the method of the present invention;

[0029] Figure 6 A flow chart of an embodiment of a second determination method for determining the maximum temperature difference of the current working environment temperature of the refrigerant detection device in the method of the present invention;

[0030] Figure 7 A schematic structural diagram of an embodiment of a control device for an air conditioner of the present invention;

[0031] Figure 8 A schematic flow chart of an embodiment of a refrigerant leakage protection control method for an R32 flammable refrigerant air conditioner according to the present invention;

[0032] Fig. 9 The present invention is a flowchart of another embodiment of a refrigerant leakage protection control method for an R32 flammable refrigerant air conditioner.

[0033] In conjunction with the accompanying drawings, the reference numerals in the embodiments of the present invention are as follows:

[0034] 102 - acquisition unit; 104 - control unit. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0036] Considering that in the relevant schemes, there are cases where there is no leakage but a false alarm occurs in the detection of whether the refrigerant of the air conditioner has leaked. For example, some schemes provide a method for detecting refrigerant leakage, when the first concentration detected by the refrigerant sensor of the air conditioner is greater than a preset concentration, a preset process is performed to reduce the refrigerant concentration at the detection position where the refrigerant detection device is located; after performing the preset process, a second concentration detected by the refrigerant detection device is obtained; and whether there is a refrigerant leakage is determined based on the second concentration.

[0037] Other schemes provide a refrigerant leakage detection method by obtaining the refrigerant concentration at a first moment and the refrigerant concentration at a second moment at a predetermined sampling point, 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, the first moment and the second moment; and determining whether the refrigerant is leaking based on the refrigerant concentration change rate.

[0038] However, the above solutions are all based on the fact 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 will be affected by temperature. For some sensors based on physical principles, such as infrared sensors, temperature changes will affect their absorption and detection capabilities of refrigerant molecules. At different temperatures, the sensitivity, response time and other parameters of the sensor may change, resulting in a deviation between the detected refrigerant concentration value and the actual value. Rapid temperature changes, such as frosting and defrosting of the evaporator, may also cause the sensor detection temperature to change as above. At this time, detection deviations may occur, leading to false alarms of leak protection shutdowns.

[0039] Therefore, the scheme of the present invention proposes a control method for an air conditioner, specifically a refrigerant leakage protection control method for an R32 flammable refrigerant air conditioner. On the basis of 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, thereby avoiding 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) in cases where the evaporator is frosted or defrosted, thereby achieving reliable protection against refrigerant leakage of the R32 flammable refrigerant air conditioner and improving user experience.

[0040] According to an embodiment of the present invention, a method for controlling an air conditioner is provided. Figure 1 A flow chart of an embodiment of the method of the present invention is shown. 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 the location of the refrigerant detection device itself, which is recorded as the current refrigerant concentration detected by the refrigerant detection device; the refrigerant detection device is arranged in the indoor unit at a location where all potential leakage points (such as locations where refrigerant leakage may occur in the indoor unit) are easily detected, such as pipe welding points, 90° bending positions of pipes, etc. The refrigerant detection device is arranged in the indoor unit at a location where all potential leakage points (such as locations where refrigerant leakage may occur in the indoor unit) are easily detected, such as pipe welding points, 90° bending positions of pipes, etc. In the scheme of the present invention, Figure 1 As shown, the control method of the air conditioner includes: steps S110 to S140.

[0041] At step S110, after the air conditioner is powered on, if the refrigerant detection device itself can work, the current refrigerant concentration detected by the refrigerant detection device is obtained; and the current working environment temperature of the refrigerant detection device is obtained. The current refrigerant concentration detected by the refrigerant detection device is such as the refrigerant concentration v detected by the refrigerant sensor; the current working environment temperature of the refrigerant detection device is the environment temperature at the location of the refrigerant detection device itself, such as: setting a temperature sensor within a preset distance range of the refrigerant sensor to obtain the working environment temperature at the location of the refrigerant sensor, or using the temperature sensor of the indoor heat exchanger or the indoor environment temperature sensor of the indoor unit to obtain the working environment temperature at the location of the refrigerant sensor. The refrigerant detection device itself can work, that is, the refrigerant detection device itself can operate 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, wherein the preset concentration threshold is, for example, a preset concentration value va, which is between 10% and 15% of the refrigerant concentration LFL.

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

[0044] At step S140, 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, then 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 are combined to determine whether the indoor unit has a refrigerant leak; and if it is determined that the indoor unit has a refrigerant leak, the air conditioner is controlled to execute a preset refrigerant leakage fault protection mechanism, such as determining that the air conditioner has a refrigerant leakage fault to shut down the air conditioner for protection. Of course, if it is determined that the indoor unit has no refrigerant leak, the air conditioner is controlled to maintain the current state of the air conditioner.

[0045] The scheme of the present invention aims to solve the problem that when the refrigerant sensor is running in the air-conditioning unit, the ambient temperature at the location of the refrigerant sensor changes rapidly due to frost or defrost, resulting in a deviation in the detection value of the refrigerant sensor, causing a false alarm of leakage protection shutdown. A refrigerant leakage protection control scheme for an air conditioner with R32 flammable refrigerant is provided. The scheme can accurately determine whether the refrigerant is leaking by detecting the concentration value of the refrigerant sensor in combination with the change in the ambient temperature at the location of the refrigerant sensor, thereby avoiding the influence of the unit operating parameters on the refrigerant sensor detection value during the use of the air conditioner. The scheme has the advantage of reliable detection results, and can achieve reliable protection against refrigerant leakage of the air conditioner with R32 flammable refrigerant.

[0046] In some embodiments, the indoor unit also has 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 arranged at a position within a set distance range from the refrigerant detection device, is used to detect the temperature at a position within a set distance range from the refrigerant detection device; the second temperature detection module, such as a temperature sensor arranged 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 arranged on the indoor unit, is used to detect the indoor ambient temperature of the indoor unit.

[0047] The current working environment temperature of the refrigerant detection device is obtained in step S110, including any one of the following obtaining methods: a first obtaining method and a second obtaining method.

[0048] Among them, the first acquisition method: acquiring the temperature at a position within a set distance range from the refrigerant detection device detected by the first temperature detection module, and recording it as the current working environment temperature of the refrigerant detection device.

[0049] In the scheme of the present invention, the indoor unit of the air conditioner is provided with a temperature detection device and a refrigerant concentration detection device. The refrigerant concentration detection device is generally a refrigerant sensor, which is mainly used to detect the refrigerant concentration at the position of the refrigerant sensor. The refrigerant sensor is preferably arranged at a position in the air conditioner where refrigerant leakage is likely to occur, such as the evaporator elbow welding point, the 90° bend position of the pipeline, the position where the pipeline wall thickness is weak, and the like. At the same time, a temperature sensor is arranged near the refrigerant sensor to detect the ambient temperature at the location of the refrigerant sensor, so as to avoid false alarms caused by distortion of the concentration detection value caused by a sudden change in the ambient temperature at the location of the refrigerant sensor, thereby achieving reliable protection against refrigerant leakage of the R32 flammable refrigerant air conditioner and improving the user experience. Among them, the vicinity of the refrigerant sensor is a position relatively close to the refrigerant sensor, and the ambient air circulation can detect the ambient temperature at the location of the refrigerant sensor.

[0050] The second acquisition method: obtain the pipe temperature of the indoor heat exchanger of the indoor unit detected by the second temperature detection module, and obtain the indoor ambient temperature of the indoor unit detected by the third temperature detection module; 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 working ambient temperature of the refrigerant detection device.

[0051] In the solution of the present invention, if the refrigerant sensor is relatively 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 also be used directly for judgment. At this time, ΔT can be replaced by Max(ΔT1, ΔT2), where ΔT1 is the maximum difference in the indoor heat exchanger temperature within the time t1, and ΔT2 is the maximum difference in the indoor ambient temperature within the time t1. It is mainly to judge whether the working temperature of the refrigerant sensor has changed. The working temperature of the refrigerant sensor will not change due to the temperature change of the evaporator, thereby causing detection failure and false alarm.

[0052] In some embodiments, in step S140, when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, the specific process of determining whether a refrigerant leak occurs in the indoor unit is based on 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. Please refer to the following exemplary description.

[0053] Combine the following Figure 2 The method of the present invention is shown as a flow chart of an embodiment of determining whether a refrigerant leakage occurs by 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, further illustrating the specific process of determining whether a refrigerant leakage occurs by 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 in step S140, including: steps S210 to S230.

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

[0055] Step S220, when the current refrigerant concentration detected by the refrigerant detection device is less than the preset concentration threshold, if it is determined that the maximum temperature difference of the current working environment temperature of the refrigerant detection device is less than the preset temperature threshold under the current target operation mode of the air conditioner, it is determined that a refrigerant leak occurs in the indoor unit.

[0056] Step S230, when the current refrigerant concentration detected by the refrigerant detection device is less than the preset concentration threshold, 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 operation mode of the air conditioner, then combined 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 a refrigerant leak.

[0057] Related solutions use temperature sensors to detect evaporator temperature or condenser temperature to determine the system operating status, mainly based on the fact that refrigerant leakage will cause the system refrigeration effect to deteriorate, and the difference between the pipe temperature and the refrigerant when there is no leakage; when the actual unit is running, in addition to refrigerant leakage, non-refrigerant leakage conditions such as too long connecting pipes and system blockage may also cause the same phenomenon, which cannot be distinguished. The solution of the present invention mainly judges based on the concentration value detected by the refrigerant sensor, but adds temperature detection on the basis of the judgment based on the concentration value detected by the refrigerant sensor to assist in confirming the accuracy of the concentration value detected by the refrigerant sensor, avoiding false alarms caused by distortion of the concentration detection value caused by sudden changes in the working environment temperature of the refrigerant sensor (i.e., the temperature near the refrigerant sensor) when the evaporator is frosted and defrosted, thereby achieving reliable protection against refrigerant leakage of R32 flammable refrigerant air conditioners and improving user experience.

[0058] In some embodiments, in step S230, 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 working environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operation mode of the air conditioner, the specific process of determining whether a refrigerant leakage occurs in the indoor unit is combined with the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device. Please refer to the following exemplary description.

[0059] Combine the following Figure 3 The method of the present invention is shown as a flow chart of an embodiment of determining whether a refrigerant leakage occurs in combination with the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device, further illustrating the specific process of determining whether a refrigerant leakage occurs in combination with the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device in step S230, including: steps S310 to S330.

[0060] Step S310, when the current refrigerant concentration detected by the refrigerant detection device is less than the 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 operation mode of the air conditioner, determine whether the current state of the air conditioner is a preset shutdown state or a preset operation state. The preset shutdown state refers to the shutdown state of the compressor, including shutdown, stopping the compressor at a temperature point, and other states; the preset operation state refers to the state of the compressor operation, including cooling, dehumidification, heating, and other modes.

[0061] Step S320, when the current refrigerant concentration detected by the refrigerant detection device is less than the 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 operation mode of the air conditioner, if it is determined that the current state of the air conditioner is the shutdown state, it is determined that a refrigerant leak occurs in the indoor unit.

[0062] Step S330, when the current refrigerant concentration detected by the refrigerant detection device is less than the 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 operation mode of the air conditioner, if it is determined that the current state of the air conditioner is the operation state, the air conditioner is controlled to shut down, and then whether the indoor unit has a refrigerant leakage is determined based on the current refrigerant concentration detected by the refrigerant detection device.

[0063] In the scheme of the present invention, by combining 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 a refrigerant leakage when the current refrigerant concentration detected by the refrigerant detection device is less than the 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 operation mode of the air conditioner, thereby adding temperature detection on the basis of the judgment based on the concentration value detected by the refrigerant sensor to assist in confirming the accuracy of the concentration value detected by the refrigerant sensor, avoiding false alarms caused by distortion of the concentration detection value due to a sudden change in the working environment temperature of the refrigerant sensor (i.e., the temperature near the refrigerant sensor), achieving reliable protection against refrigerant leakage of R32 flammable refrigerant air conditioners and improving user experience.

[0064] In some embodiments, 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 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, the specific process of determining whether refrigerant leakage occurs in the indoor unit according to the current refrigerant concentration detected by the refrigerant detection device is described in the following exemplary description.

[0065] Combine the following Figure 4 The method of the present invention is shown as a flow chart of an embodiment of determining whether refrigerant leakage occurs in the indoor unit according to the current refrigerant concentration detected by the refrigerant detection device, further illustrating the specific process of determining whether refrigerant leakage occurs in the indoor unit according to the current refrigerant concentration detected by the refrigerant detection device in step S330, including: steps S410 to S430.

[0066] Step S410, when the current refrigerant concentration detected by the refrigerant detection device is less than the 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 operation mode of the air conditioner, and the current state of the air conditioner is the operation state, after controlling the air conditioner to stop, determine whether the current refrigerant concentration detected by the refrigerant detection device continues to rise within the preset second time.

[0067] Step S420, when the current refrigerant concentration detected by the refrigerant detection device is less than the 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 operation mode of the air conditioner, and the current state of the air conditioner is the operation 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 the preset second time, it is determined that a refrigerant leak has occurred in the indoor unit.

[0068] Step S430, when the current refrigerant concentration detected by the refrigerant detection device is less than the 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 operation mode of the air conditioner, and the current state of the air conditioner is the operation 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 the preset second time, it is determined that no refrigerant leakage has occurred in the indoor unit, and the air conditioner is controlled to restart and resume operation, specifically, the air conditioner is controlled to restart and resume to the operating state of the air conditioner before the air conditioner is controlled to stop, and then returns to continue to determine whether the current refrigerant concentration detected by the refrigerant detection device is less than the preset concentration threshold, so as to realize a cyclic determination of whether a refrigerant leakage has occurred in the indoor unit.

[0069] In the scheme of the present invention, after the air conditioner is controlled to stop, it is determined whether refrigerant leakage occurs in the indoor unit according to the current refrigerant concentration detected by the refrigerant detection device when the current refrigerant concentration detected by the refrigerant detection device is less than the 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. Therefore, temperature detection is added on the basis of judgment based on the concentration value detected by the refrigerant sensor to assist in confirming the accuracy of the concentration value detected by the refrigerant sensor, thereby avoiding false alarms caused by distortion of the concentration detection value due to a sudden change in the working environment temperature of the refrigerant sensor (i.e., the temperature near the refrigerant sensor), thereby achieving reliable protection against refrigerant leakage of R32 flammable refrigerant air conditioners and improving user experience.

[0070] In some embodiments, in step S210, 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 determined within a preset first time, including any one of the following determination methods: the first determination method and the second determination method.

[0071] Among them, the first determination method is: when the current working environment temperature of the refrigerant detection device is the temperature at a position 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 working environment temperature of the refrigerant detection device is determined within a preset first time.

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

[0073] Step S510, determining a maximum value of the current working environment temperature of the refrigerant detection device and a minimum value of the current working environment temperature of the refrigerant detection device within a preset first time.

[0074] Step S520, determining a difference between a maximum value of the current working environment temperature of the refrigerant detection device and a minimum value of the current working environment temperature of the refrigerant detection device as a maximum temperature difference of the current working environment temperature of the refrigerant detection device;

[0075] Figure 8 FIG. 1 is a flow chart of an embodiment of a refrigerant leakage protection control method for an R32 flammable refrigerant air conditioner according to the present invention. Figure 8 As shown, the refrigerant leakage protection control method of the R32 flammable refrigerant air conditioner includes:

[0076] Step 11: After the unit is powered on, first determine whether the refrigerant sensor is working properly. If so, proceed to step 12. Otherwise, it is considered that the refrigerant sensor has expired or other abnormal alarms require replacement of the refrigerant sensor. For example, if the refrigerant sensor has a communication problem or does not work after its life expires, it will directly alarm and require replacement. To determine whether the refrigerant sensor is working properly, you can specifically apply for: determining whether the refrigerant sensor can detect the refrigerant concentration after powering on, determining whether the refrigerant sensor can exchange data with the indoor unit normally, etc.

[0077] Step 12: When the refrigerant sensor is working normally, the refrigerant sensor starts to detect the refrigerant concentration v in real time and determines whether the refrigerant concentration v detected by the refrigerant sensor is lower than the preset concentration value va: if so, the unit maintains the current state, otherwise, execute step 13 to start the refrigerant leakage judgment process. When the refrigerant concentration v detected by the refrigerant sensor is lower than the preset concentration value va, the unit works normally; when the refrigerant concentration v detected by the refrigerant sensor is higher than the preset concentration value va, the refrigerant leakage judgment process starts.

[0078] The preset concentration value va is a program preset concentration value. Considering that the unit needs to be protected before the refrigerant concentration LFL (lower flammability limit) reaches 25%, and the refrigerant leakage judgment process requires t2 time, the preset concentration value va is generally between 10% and 15% of the refrigerant concentration LFL. Among them, the preset concentration value va is between 10% and 15% of the refrigerant concentration LFL. The reason for this is that it takes t2 time for the refrigerant concentration v to reach the preset concentration value va before the leakage fault is judged, so 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 leakage judgment process is started, that is, whether the maximum temperature difference ΔT detected within the time t1 is greater than the preset temperature value K: if so, execute step 14, otherwise it is judged that the refrigerant leakage fault causes the unit to shut down for protection. Among them, t1 is the preset time of the program. Considering the hysteresis of temperature detection and the timely necessity of refrigerant leakage protection, the time is selected to be about 1min; ΔT is the maximum difference detected by the temperature sensor within the time t1, that is, the difference between the maximum value and the minimum value detected within the time t1. K is the preset temperature value of the program, generally the cooling value is about 5℃, and the heating value is about 10℃.

[0080] In step 13, the refrigerant leakage judgment 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 the 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 leakage, and each load of the whole machine is processed according to the refrigerant leakage protection. Among them, each load of the whole machine is processed according to the refrigerant leakage protection. The general conventional practice is to shut down all the outdoor loads, control the electronic expansion valve that transports the refrigerant to the room, etc. to close; adjust the indoor wind gear to the highest, and the air guide plate to the smoothest position to blow away the indoor refrigerant. If the refrigerant concentration v detected by the refrigerant sensor reaches the refrigerant leakage judgment standard, and at the same time, because the working temperature of the refrigerant sensor has no sudden change, it is judged that there is no problem with the detected concentration value, and combined together it is judged that there is a refrigerant leakage.

[0081] Step 14. When the maximum temperature difference ΔT detected within time t1 ≥ 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, execute step 15; if yes, execute step 16.

[0082] Step 15: If the unit is in shutdown state (ie, the compressor is shut down), it is directly determined that there is a refrigerant leakage, and the loads of the whole unit are processed according to the refrigerant leakage protection.

[0083] Step 16: If the unit is in operation 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 first shut down, and then the refrigerant concentration v detected by the refrigerant sensor within t2 after the shutdown is detected to continue to rise: if not, step 17 is performed, and if yes, step 18 is performed. Among them, the current concentration value v is detected in real time within t2, and compared with the last detected concentration value v': if v < v' appears, it is determined that there is no continuous rise, and if v < v' has not appeared within t2, it is determined to be a continuous rise.

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

[0085] Step 18: If the refrigerant concentration v detected by the refrigerant sensor continues to rise within t2 after shutdown, it is determined to be a refrigerant leak, and each load of the entire machine is processed according to the refrigerant leakage protection.

[0086] In the scheme of the present invention, the refrigerant concentration near the indoor evaporator is detected by a refrigerant sensor, and the temperature change of the indoor heat exchanger is detected by an indoor temperature sensor to judge the accuracy of the refrigerant concentration detection value, thereby increasing the accuracy of refrigerant leakage detection, avoiding freezing or defrosting of the unit evaporator during the use of the air conditioner, resulting in changes in the temperature field near the refrigerant sensor, and causing concentration detection deviations and causing false protection, thereby achieving reliable protection against refrigerant leakage of R32 flammable refrigerant air conditioners and improving user experience.

[0087] The second determination method is: when the current working environment 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 environment temperature of the indoor unit detected by the third temperature detection module of the indoor unit, the maximum temperature difference of the current working environment temperature of the refrigerant detection device is determined within a preset first time.

[0088] Combine the following Figure 6 The flowchart of an embodiment of the second method for determining the maximum temperature difference of the current working environment temperature of the refrigerant detection device in the method of the present invention is shown, which further illustrates the specific process of the second method for 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, determine the maximum value of the tube temperature of the indoor heat exchanger of the indoor unit and the minimum value of the tube temperature of the indoor heat exchanger of the indoor unit; and determine the difference between the maximum value of the tube temperature of the indoor heat exchanger of the indoor unit and the minimum value of the tube temperature of the indoor heat exchanger of the indoor unit, which is recorded as the first difference.

[0090] Step S620, within a preset first time, 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; and determine 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, which is recorded as the second difference.

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

[0092] Fig. 9 FIG. 2 is a flow chart of another embodiment of a refrigerant leakage protection control method for an R32 flammable refrigerant air conditioner according to the present invention. Fig. 9 As shown, the refrigerant leakage protection control method of the R32 flammable refrigerant air conditioner includes:

[0093] Step 21: After the unit is powered on, first determine whether the refrigerant sensor is working properly. If so, execute step 22. Otherwise, it is considered that the refrigerant sensor has expired and other abnormal alarms need to be replaced. For example, if the refrigerant sensor has communication problems or does not work after its life expires, it will directly alarm and require replacement. Among them, to determine whether the refrigerant sensor is working properly, you can apply for: power on to determine whether the refrigerant sensor can detect the refrigerant concentration, determine whether the refrigerant sensor can exchange data with the indoor unit normally, etc.

[0094] Step 22: When the refrigerant sensor is working normally, the refrigerant sensor starts to detect the refrigerant concentration v in real time and determines whether the refrigerant concentration v detected by the refrigerant sensor is lower than the preset concentration value va: if so, the unit maintains the current state, otherwise, execute step 23 to start the refrigerant leakage judgment process. When the refrigerant concentration v detected by the refrigerant sensor is lower than the preset concentration value va, the unit works normally; when the refrigerant concentration v detected by the refrigerant sensor is higher than the preset concentration value va, the refrigerant leakage judgment process starts.

[0095] The preset concentration value va is a program preset concentration value. Considering that the unit needs to be protected before the refrigerant concentration LFL (lower flammability limit) reaches 25%, and the refrigerant leakage judgment process requires t2 time, the preset concentration value va is generally between 10% and 15% of the refrigerant concentration LFL. Among them, the preset concentration value va is between 10% and 15% of the refrigerant concentration LFL. The reason for this is that it takes t2 time for the refrigerant concentration v to reach the preset concentration value va before the leakage fault is judged, so 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 leakage judgment process is started, that is, whether the maximum temperature difference MAX(ΔT1, ΔT2) detected within the time t1 is greater than the preset temperature value K: if so, execute step 24, otherwise it is judged that the refrigerant leakage fault causes the unit to shut down for protection. Among them, t1 is the program preset time. Considering the hysteresis of temperature detection and the timely necessity of refrigerant leakage protection, the time is selected to be about 1min; MAX(ΔT1, ΔT2) is the maximum difference detected by the temperature sensor within the time t1, that is, the difference between the maximum value and the minimum value detected within the time t1. K is the program preset temperature value, generally around 5°C for cooling and around 10°C for heating.

[0097] In step 23, the refrigerant leakage judgment 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 the 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 leakage, and each load of the whole machine is processed according to the refrigerant leakage protection. Among them, each load of the whole machine is processed according to the refrigerant leakage protection. The general conventional practice is to shut down all the outdoor loads, control the electronic expansion valve that transports the refrigerant to the room, etc. to close; adjust the indoor wind gear to the highest, and the air guide plate to the smoothest position to blow away the indoor refrigerant. If the refrigerant concentration v detected by the refrigerant sensor reaches the refrigerant leakage judgment standard, and at the same time, because the working temperature of the refrigerant sensor does not change suddenly, it is judged that there is no problem with the detected concentration value, and combined together it is judged that there is a refrigerant leakage.

[0098] Step 24. When the maximum temperature difference MAX(ΔT1, ΔT2) detected within time t1 is ≥ 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, execute step 25; if yes, execute step 26.

[0099] Step 25: If the unit is in shutdown state (ie, the compressor is shut down), it is directly determined that there is a refrigerant leakage, and the loads of the whole unit are processed according to the refrigerant leakage protection.

[0100] Step 26. If the unit is in operation 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 first shut down, and then it is detected whether the refrigerant concentration v detected by the refrigerant sensor will continue to rise within t2 time after shutdown: if not, execute step 27; if so, execute step 28.

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

[0102] Step 28: If the refrigerant concentration v detected by the refrigerant sensor continues to rise within t2 after shutdown, it is determined to be a refrigerant leak, and each load of the entire machine is processed according to the refrigerant leakage protection.

[0103] In the solution of the present invention, by detecting the concentration value of the refrigerant sensor, combined with the indoor evaporator temperature and the indoor ambient temperature, it is determined whether the refrigerant has leaked. By detecting the indoor ambient temperature and the evaporator temperature, the detection deviation caused by the rapid change of the evaporator temperature can be eliminated, and reliable protection against refrigerant leakage of the R32 flammable refrigerant air conditioner can be achieved, thereby improving the user experience.

[0104] By adopting the technical solution of the present embodiment, a refrigerant sensor is set at a position where a refrigerant leakage may occur in the air-conditioning unit, and a temperature sensor is set within a preset distance range of the refrigerant sensor to obtain the working environment temperature at the position where the refrigerant sensor is located (or the temperature sensor of the indoor heat exchanger or the indoor environment temperature sensor of the indoor unit is used to obtain the working environment temperature at the position where the refrigerant sensor is located); after the air conditioner is powered on, if the refrigerant sensor itself can work normally, the refrigerant concentration detected by the refrigerant sensor and the working environment temperature at the position where the refrigerant sensor is located are combined to determine whether a refrigerant leakage occurs in the air conditioner, and the air conditioner is controlled to shut down for protection when a refrigerant leakage occurs; thereby, by combining the refrigerant concentration detected by the refrigerant sensor and the working environment temperature at the position where the refrigerant sensor is located, it is possible to accurately determine whether a refrigerant leakage occurs in the air conditioner, avoid false alarms caused by distortion of the refrigerant concentration detected by the refrigerant sensor due to changes in the working environment temperature at the position where the refrigerant sensor is located, improve the reliability of refrigerant leakage protection, and improve user experience.

[0105] According to an embodiment of the present invention, a control device for an air conditioner corresponding to the control method for the air conditioner is also provided. Figure 7The schematic diagram of the structure of an embodiment of the device of the present invention is shown. 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 the location of the refrigerant detection device itself, which is recorded as the current refrigerant concentration detected by the refrigerant detection device; the refrigerant detection device is arranged at a location in the indoor unit where all potential leakage points (such as locations where refrigerant leakage may occur in the indoor unit) can be easily detected, such as pipe welding points, 90° bends in the pipes, etc.; in the scheme of the present invention, Figure 7 As shown, the control device of the air conditioner includes: an acquisition unit 102 and a control unit 104.

[0106] Wherein, the acquisition unit 102 is configured to acquire the current refrigerant concentration detected by the refrigerant detection device after the air conditioner is powered on, when the refrigerant detection device itself can work; and acquire the current working environment temperature of the refrigerant detection device; wherein, the current refrigerant concentration detected by the refrigerant detection device is such as the refrigerant concentration v detected by the refrigerant sensor; the current working environment temperature of the refrigerant detection device is the environment temperature at the location where the refrigerant detection device itself is located, such as: setting a temperature sensor within a preset distance range of the refrigerant sensor to acquire the working environment temperature at the location where the refrigerant sensor is located, or using the temperature sensor of the indoor heat exchanger or the indoor environment temperature sensor of the indoor unit to acquire the working environment temperature at the location where the refrigerant sensor is located. The specific functions and processing of the acquisition unit 102 refer to 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 is, for example, a preset concentration value va, and the preset concentration value va is between 10% and 15% of the refrigerant concentration LFL. The specific functions and processing of the control unit 104 refer to step S120.

[0108] The control unit 104 is further configured to control the air conditioner to maintain the current state of the air conditioner 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 also shown in step S130.

[0109] The control unit 104 is also configured to determine whether the indoor unit has a refrigerant leak 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, based on 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; and, if it is determined that the indoor unit has a refrigerant leak, control the air conditioner to execute a preset refrigerant leakage fault protection mechanism, such as determining that the air conditioner has a refrigerant leakage fault to cause the air conditioner to shut down for protection. Of course, the control unit 104 is also configured to control the air conditioner to maintain the current state of the air conditioner if it is determined that the indoor unit has no refrigerant leak. The specific functions and processing of the control unit 104 are also shown in step S140.

[0110] The scheme of the present invention aims to solve the problem that when the refrigerant sensor is running in the air-conditioning unit, the ambient temperature at the location of the refrigerant sensor changes rapidly due to frost or defrost, resulting in a deviation in the detection value of the refrigerant sensor, causing a false alarm of leakage protection shutdown. A refrigerant leakage protection control scheme for an air conditioner with R32 flammable refrigerant is provided. The scheme can accurately determine whether the refrigerant is leaking by detecting the concentration value of the refrigerant sensor in combination with the change in the ambient temperature at the location of the refrigerant sensor, thereby avoiding the influence of the unit operating parameters on the refrigerant sensor detection value during the use of the air conditioner. The scheme has the advantage of reliable detection results, and can achieve reliable protection against refrigerant leakage of the air conditioner with R32 flammable refrigerant.

[0111] In some implementations, the indoor unit further has 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] Wherein, the first temperature detection module, such as a temperature sensor arranged at a position within a set distance range from the refrigerant detection device, is used to detect the temperature at a position within a set distance range from the refrigerant detection device.

[0113] 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.

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

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

[0116] The first acquisition method: the acquisition unit 102 is further configured to acquire the temperature of a position 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 the scheme of the present invention, the indoor unit of the air conditioner is provided with a temperature detection device and a refrigerant concentration detection device. The refrigerant concentration detection device is generally a refrigerant sensor, which is mainly used to detect the refrigerant concentration at the position of the refrigerant sensor. The refrigerant sensor is preferably arranged at a position in the air conditioner where refrigerant leakage is likely to occur. At the same time, a temperature sensor is arranged near the refrigerant sensor to detect the ambient temperature at the position of the refrigerant sensor, so as to avoid false alarms caused by distortion of the concentration detection value caused by a sudden change in the ambient temperature at the position of the refrigerant sensor, thereby achieving reliable protection against refrigerant leakage of the R32 flammable refrigerant air conditioner and improving the user experience. Among them, the vicinity of the refrigerant sensor is a position relatively close to the refrigerant sensor, and the ambient air circulation can detect the ambient temperature at the position of the refrigerant sensor.

[0118] The second acquisition method: the acquisition unit 102 is specifically 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 working ambient temperature of the refrigerant detection device.

[0119] In the solution of the present invention, if the refrigerant sensor is relatively 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 also be used directly for judgment. At this time, ΔT can be replaced by Max(ΔT1, ΔT2), where ΔT1 is the maximum difference in the indoor heat exchanger temperature within the time t1, and ΔT2 is the maximum difference in the indoor ambient temperature within the time t1. It is mainly to judge whether the working temperature of the refrigerant sensor has changed. The working temperature of the refrigerant sensor will not change due to the temperature change of the evaporator, thereby causing detection failure and false alarm.

[0120] In some embodiments, the control unit 104 determines whether a refrigerant leak occurs in the indoor unit by 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 when the current refrigerant concentration detected by the refrigerant detection device is less than a preset concentration threshold, including:

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

[0122] The control unit 104 is further configured to determine that a refrigerant leak occurs in the indoor unit if the maximum temperature difference of the current working environment temperature of the refrigerant detection device is less than the preset temperature threshold value under the current target operation mode of the air conditioner when the current refrigerant concentration detected by the refrigerant detection device is less than the preset concentration threshold value. The specific functions and processing of the control unit 104 are also shown in step S220.

[0123] The control unit 104 is further configured to determine whether a refrigerant leak occurs in the indoor unit in combination with the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device, if 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 operation mode of the air conditioner when the current refrigerant concentration detected by the refrigerant detection device is less than the preset concentration threshold. The specific functions and processing of the control unit 104 are also referred to step S230.

[0124] Related solutions use temperature sensors to detect evaporator temperature or condenser temperature to determine the system operating status, mainly based on the fact that refrigerant leakage will cause the system refrigeration effect to deteriorate, and the difference between the pipe temperature and the refrigerant when there is no leakage; when the actual unit is running, in addition to refrigerant leakage, non-refrigerant leakage conditions such as too long connecting pipes and system blockage may also cause the same phenomenon, which cannot be distinguished. The solution of the present invention mainly judges based on the concentration value detected by the refrigerant sensor, but adds temperature detection on the basis of the judgment based on the concentration value detected by the refrigerant sensor to assist in confirming the accuracy of the concentration value detected by the refrigerant sensor, avoiding false alarms caused by distortion of the concentration detection value caused by sudden changes in the working environment temperature of the refrigerant sensor (i.e., the temperature near the refrigerant sensor) when the evaporator is frosted and defrosted, thereby achieving reliable protection against refrigerant leakage of R32 flammable refrigerant air conditioners and improving user experience.

[0125] In some embodiments, the control unit 104 determines whether a refrigerant leak occurs in the indoor unit in combination with the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device 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 working environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operation mode of the air conditioner, 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 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. The specific functions and processing of the control unit 104 are also referred to step S310.

[0127] The control unit 104 is further configured to determine that a refrigerant leak occurs in the indoor unit if the current state of the air conditioner is determined to be the shutdown 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 working environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operation mode of the air conditioner. The specific functions and processing of the control unit 104 are also shown in step S320.

[0128] The control unit 104 is further configured to, 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 operation mode of the air conditioner, control the air conditioner to stop if it is determined that the current state of the air conditioner is the operation state, and then determine whether the indoor unit has a refrigerant leak according to the current refrigerant concentration detected by the refrigerant detection device. The specific functions and processing of the control unit 104 are also shown in step S330.

[0129] In the scheme of the present invention, by combining 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 a refrigerant leakage when the current refrigerant concentration detected by the refrigerant detection device is less than the 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 operation mode of the air conditioner, thereby adding temperature detection on the basis of the judgment based on the concentration value detected by the refrigerant sensor to assist in confirming the accuracy of the concentration value detected by the refrigerant sensor, avoiding false alarms caused by distortion of the concentration detection value due to a sudden change in the working environment temperature of the refrigerant sensor (i.e., the temperature near the refrigerant sensor), achieving reliable protection against refrigerant leakage of R32 flammable refrigerant air conditioners and improving user experience.

[0130] 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, 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 operation mode of the air conditioner, and the current state of the air conditioner is the operation state, controls the air conditioner to stop, and then determines whether the indoor unit has a refrigerant leak according to the current refrigerant concentration detected by the refrigerant detection device, including:

[0131] The control unit 104 is further configured to control the air conditioner to stop after determining whether the current refrigerant concentration detected by the refrigerant detection device continues to rise within a preset second time 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 operation mode of the air conditioner, and the current state of the air conditioner is the operation state. The specific functions and processing of the control unit 104 are also shown in step S410.

[0132] The control unit 104 is further configured to control the air conditioner to stop after the air conditioner is stopped, if it is determined that the current refrigerant concentration detected by the refrigerant detection device continues to rise within a preset second time, then determine that the indoor unit has a refrigerant leak. The specific functions and processing of the control unit 104 are also shown 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 working environment temperature of the refrigerant detection device is greater than or equal to the preset temperature threshold in the current target operation mode of the air conditioner, and the current state of the air conditioner is the operation 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 the preset second time, it is determined that no refrigerant leakage occurs in the indoor unit, and the air conditioner is controlled to restart and resume operation, specifically, the air conditioner is controlled to restart and resume to the operating state of the air conditioner before the air conditioner is controlled to stop, and then returns to continue to determine whether the current refrigerant concentration detected by the refrigerant detection device is less than the preset concentration threshold, so as to realize a cyclic determination of whether the indoor unit has a refrigerant leakage. The specific functions and processing of the control unit 104 are also shown in step S430.

[0134] In the scheme of the present invention, after the air conditioner is controlled to stop, it is determined whether refrigerant leakage occurs in the indoor unit according to the current refrigerant concentration detected by the refrigerant detection device when the current refrigerant concentration detected by the refrigerant detection device is less than the 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. Therefore, temperature detection is added on the basis of judgment based on the concentration value detected by the refrigerant sensor to assist in confirming the accuracy of the concentration value detected by the refrigerant sensor, thereby avoiding false alarms caused by distortion of the concentration detection value due to a sudden change in the working environment temperature of the refrigerant sensor (i.e., the temperature near the refrigerant sensor), thereby achieving reliable protection against refrigerant leakage of R32 flammable refrigerant air conditioners and improving user experience.

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

[0136] The control unit 104 determines the maximum temperature difference of the current working environment temperature of the refrigerant detection device within a preset first time when the current working environment temperature of the refrigerant detection device is the temperature at a position within a set distance range from the refrigerant detection device detected by the first temperature detection module of the indoor unit, i.e., the first determination method:

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

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

[0139] Figure 8 FIG. 1 is a flow chart of an embodiment of a refrigerant leakage protection control method for an R32 flammable refrigerant air conditioner according to the present invention. Figure 8 As shown, the refrigerant leakage protection control method of the R32 flammable refrigerant air conditioner includes:

[0140] Step 11: After the unit is powered on, first determine whether the refrigerant sensor is working properly. If so, proceed to step 12. Otherwise, it is considered that the refrigerant sensor has expired or other abnormal alarms require replacement of the refrigerant sensor. For example, if the refrigerant sensor has a communication problem or does not work after its life expires, it will directly alarm and require replacement. To determine whether the refrigerant sensor is working properly, you can specifically apply for: determining whether the refrigerant sensor can detect the refrigerant concentration after powering on, determining whether the refrigerant sensor can exchange data with the indoor unit normally, etc.

[0141] Step 12: When the refrigerant sensor is working normally, the refrigerant sensor starts to detect the refrigerant concentration v in real time and determines whether the refrigerant concentration v detected by the refrigerant sensor is lower than the preset concentration value va: if so, the unit maintains the current state, otherwise, execute step 13 to start the refrigerant leakage judgment process. When the refrigerant concentration v detected by the refrigerant sensor is lower than the preset concentration value va, the unit works normally; when the refrigerant concentration v detected by the refrigerant sensor is higher than the preset concentration value va, the refrigerant leakage judgment process starts.

[0142] The preset concentration value va is a program preset concentration value. Considering that the unit needs to be protected before the refrigerant concentration LFL (lower flammability limit) reaches 25%, and the refrigerant leakage judgment process requires t2 time, the preset concentration value va is generally between 10% and 15% of the refrigerant concentration LFL. Among them, the preset concentration value va is between 10% and 15% of the refrigerant concentration LFL. The reason for this is that it takes t2 time for the refrigerant concentration v to reach the preset concentration value va before the leakage fault is judged, so 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 leakage judgment process is started, that is, whether the maximum temperature difference ΔT detected within the time t1 is greater than the preset temperature value K: if so, execute step 14, otherwise it is judged that the refrigerant leakage fault causes the unit to shut down for protection. Among them, t1 is the preset time of the program. Considering the hysteresis of temperature detection and the timely necessity of refrigerant leakage protection, the time is selected to be about 1min; ΔT is the maximum difference detected by the temperature sensor within the time t1, that is, the difference between the maximum value and the minimum value detected within the time t1. K is the preset temperature value of the program, generally the cooling value is about 5℃, and the heating value is about 10℃.

[0144] In step 13, the refrigerant leakage judgment 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 the 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 leakage, and each load of the whole machine is processed according to the refrigerant leakage protection. Among them, each load of the whole machine is processed according to the refrigerant leakage protection. The general conventional practice is to shut down all the outdoor loads, control the electronic expansion valve that transports the refrigerant to the room, etc. to close; adjust the indoor wind gear to the highest, and the air guide plate to the smoothest position to blow away the indoor refrigerant. If the refrigerant concentration v detected by the refrigerant sensor reaches the refrigerant leakage judgment standard, and at the same time, because the working temperature of the refrigerant sensor has no sudden change, it is judged that there is no problem with the detected concentration value, and combined together it is judged that there is a refrigerant leakage.

[0145] Step 14. When the maximum temperature difference ΔT detected within time t1 ≥ 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, execute step 15; if yes, execute step 16.

[0146] Step 15: If the unit is in shutdown state (ie, the compressor is shut down), it is directly determined that there is a refrigerant leakage, and the loads of the whole unit are processed according to the refrigerant leakage protection.

[0147] Step 16. If the unit is in operation 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 first shut down, and then it is detected whether the refrigerant concentration v detected by the refrigerant sensor will continue to rise within t2 time after shutdown: if not, execute step 17; if yes, execute step 18.

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

[0149] Step 18: If the refrigerant concentration v detected by the refrigerant sensor continues to rise within t2 after shutdown, it is determined to be a refrigerant leak, and each load of the entire machine is processed according to the refrigerant leakage protection.

[0150] In the scheme of the present invention, the refrigerant concentration near the indoor evaporator is detected by a refrigerant sensor, and the temperature change of the indoor heat exchanger is detected by an indoor temperature sensor to judge the accuracy of the refrigerant concentration detection value, thereby increasing the accuracy of refrigerant leakage detection, avoiding freezing or defrosting of the unit evaporator during the use of the air conditioner, resulting in changes in the temperature field near the refrigerant sensor, and causing concentration detection deviations and causing false protection, thereby achieving reliable protection against refrigerant leakage of R32 flammable refrigerant air conditioners and improving user experience.

[0151] The control unit 104 determines the maximum temperature difference of the current working ambient temperature of the refrigerant detection device within a preset first time, i.e., the second determination method, when the current working ambient temperature of the refrigerant detection device is the tube 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:

[0152] The control unit 104 is further configured to 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 within a preset first time; 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, which is recorded as the first difference. The specific functions and processing of the control unit 104 are also referred to step S610.

[0153] The control unit 104 is further configured to determine the maximum value of the indoor environment temperature of the indoor unit and the minimum value of the indoor environment temperature of the indoor unit within a preset first time; and determine the difference between the maximum value of the indoor environment temperature of the indoor unit and the minimum value of the indoor environment temperature of the indoor unit, which is recorded as the second difference. The specific functions and processing of the control unit 104 are also shown in step S620.

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

[0155] Fig. 9 FIG. 2 is a flow chart of another embodiment of a refrigerant leakage protection control method for an R32 flammable refrigerant air conditioner according to the present invention. Fig. 9As shown, the refrigerant leakage protection control method of the R32 flammable refrigerant air conditioner includes:

[0156] Step 21: After the unit is powered on, first determine whether the refrigerant sensor is working properly. If so, execute step 22. Otherwise, it is considered that the refrigerant sensor has expired and other abnormal alarms need to be replaced. For example, if the refrigerant sensor has communication problems or does not work after its life expires, it will directly alarm and require replacement. Among them, to determine whether the refrigerant sensor is working properly, you can apply for: power on to determine whether the refrigerant sensor can detect the refrigerant concentration, determine whether the refrigerant sensor can exchange data with the indoor unit normally, etc.

[0157] Step 22: When the refrigerant sensor is working normally, the refrigerant sensor starts to detect the refrigerant concentration v in real time and determines whether the refrigerant concentration v detected by the refrigerant sensor is lower than the preset concentration value va: if so, the unit maintains the current state, otherwise, execute step 23 to start the refrigerant leakage judgment process. When the refrigerant concentration v detected by the refrigerant sensor is lower than the preset concentration value va, the unit works normally; when the refrigerant concentration v detected by the refrigerant sensor is higher than the preset concentration value va, the refrigerant leakage judgment process starts.

[0158] The preset concentration value va is a program preset concentration value. Considering that the unit needs to be protected before the refrigerant concentration LFL (lower flammability limit) reaches 25%, and the refrigerant leakage judgment process requires t2 time, the preset concentration value va is generally between 10% and 15% of the refrigerant concentration LFL. Among them, the preset concentration value va is between 10% and 15% of the refrigerant concentration LFL. The reason for this is that it takes t2 time for the refrigerant concentration v to reach the preset concentration value va before the leakage fault is judged, so 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 leakage judgment process is started, that is, whether the maximum temperature difference MAX(ΔT1, ΔT2) detected within the time t1 is greater than the preset temperature value K: if so, execute step 24, otherwise it is judged that the refrigerant leakage fault causes the unit to shut down for protection. Among them, t1 is the program preset time. Considering the hysteresis of temperature detection and the timely necessity of refrigerant leakage protection, the time is selected to be about 1min; MAX(ΔT1, ΔT2) is the maximum difference detected by the temperature sensor within the time t1, that is, the difference between the maximum value and the minimum value detected within the time t1. K is the program preset temperature value, generally around 5°C for cooling and around 10°C for heating.

[0160] In step 23, the refrigerant leakage judgment 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 the 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 leakage, and each load of the whole machine is processed according to the refrigerant leakage protection. Among them, each load of the whole machine is processed according to the refrigerant leakage protection. The general conventional practice is to shut down all the outdoor loads, control the electronic expansion valve that transports the refrigerant to the room, etc. to close; adjust the indoor wind gear to the highest, and the air guide plate to the smoothest position to blow away the indoor refrigerant. If the refrigerant concentration v detected by the refrigerant sensor reaches the refrigerant leakage judgment standard, and at the same time, because the working temperature of the refrigerant sensor does not change suddenly, it is judged that there is no problem with the detected concentration value, and combined together it is judged that there is a refrigerant leakage.

[0161] Step 24. When the maximum temperature difference MAX(ΔT1, ΔT2) detected within time t1 is ≥ 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, execute step 25; if yes, execute step 26.

[0162] Step 25: If the unit is in shutdown state (ie, the compressor is shut down), it is directly determined that there is a refrigerant leakage, and the loads of the whole unit are processed according to the refrigerant leakage protection.

[0163] Step 26. If the unit is in operation 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 first shut down, and then it is detected whether the refrigerant concentration v detected by the refrigerant sensor will continue to rise within t2 time after shutdown: if not, execute step 27; if so, execute step 28.

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

[0165] Step 28: If the refrigerant concentration v detected by the refrigerant sensor continues to rise within t2 after shutdown, it is determined to be a refrigerant leak, and each load of the entire machine is processed according to the refrigerant leakage protection.

[0166] In the solution of the present invention, by detecting the concentration value of the refrigerant sensor, combined with the indoor evaporator temperature and the indoor ambient temperature, it is determined whether the refrigerant has leaked. By detecting the indoor ambient temperature and the evaporator temperature, the detection deviation caused by the rapid change of the evaporator temperature can be eliminated, and reliable protection against refrigerant leakage of the R32 flammable refrigerant air conditioner can be achieved, thereby improving the user experience.

[0167] Since the processing and functions implemented by the device of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned method, for the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments, and no further elaboration will be made here.

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

[0169] Since the processing and functions implemented by the air conditioner of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned devices, for the details not fully described in this embodiment, please refer to 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 air conditioner control method is also provided, including a computer program, which implements the steps of the air conditioner control method described above when executed by a processor.

[0171] Since the processing and functions implemented by the product of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned method, for the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments, and no further elaboration will be made here.

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

[0173] Since the processing and functions implemented by the storage medium of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned method, for the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments, and no further elaboration will be made here.

[0174] In summary, it is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0175] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the claims of the present invention.

Claims

1. A method for controlling 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 the location of the refrigerant detection device itself, which is recorded as the current refrigerant concentration detected by the refrigerant detection device; The control method of the air conditioner comprises: After the air conditioner is powered on, when the refrigerant detection device itself is able to work, obtaining the current refrigerant concentration detected by the refrigerant detection device; and obtaining the current working environment 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 a preset concentration threshold, controlling the air conditioner to maintain the current state of the air conditioner; 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 in combination with 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, it is determined whether a refrigerant leakage has occurred in the indoor unit; and, if it is determined that a refrigerant leakage has occurred in the indoor unit, the air conditioner is controlled to execute a preset refrigerant leakage fault protection mechanism.

2. The air conditioner control method according to claim 1, characterized in that: The indoor unit further comprises a temperature detection device; the temperature detection device comprises 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 tube temperature of the indoor heat exchanger of the indoor unit; The third temperature detection module is used to detect the indoor environment temperature of the indoor unit; Obtaining the current working environment temperature of the refrigerant detection device includes any of the following obtaining methods: The first acquisition method: acquiring the temperature at a position within a set distance range from the refrigerant detection device detected by the first temperature detection module, and recording it as the current working environment temperature of the refrigerant detection device; The second acquisition method: obtain the pipe temperature of the indoor heat exchanger of the indoor unit detected by the second temperature detection module, and obtain the indoor ambient temperature of the indoor unit detected by the third temperature detection module; 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 working ambient temperature of the refrigerant detection device.

3. The air conditioner control method according to claim 1 or 2, characterized in that: Determining whether a refrigerant leak occurs in the indoor unit by 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 includes: Determine the maximum temperature difference of the current working environment temperature of the refrigerant detection device within a preset first time; and determine whether the maximum temperature difference of the current working environment temperature of the refrigerant detection device is greater than or equal to a preset temperature threshold value in the current target operation mode of the air conditioner; If it is determined that the maximum temperature difference of the current working environment temperature of the refrigerant detection device is less than the preset temperature threshold value in the current target operation mode of the air conditioner, it is determined that the indoor unit has a refrigerant leak; 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 under the current target operation mode of the air conditioner, then combined with the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device, it is determined whether a refrigerant leak occurs in the indoor unit.

4. The control method of the air conditioner according to claim 3, characterized in that: Determining whether refrigerant leakage occurs in the indoor unit based on the current state of the air conditioner and the current refrigerant concentration detected by the refrigerant detection device includes: Determining 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 shutdown state, it is determined that a refrigerant leak occurs in the indoor unit; If it is determined that the current state of the air conditioner is the running state, the air conditioner is controlled to be shut down, and then whether a refrigerant leak occurs in the indoor unit is determined based on the current refrigerant concentration detected by the refrigerant detection device.

5. The air conditioner control method according to claim 4, characterized in that: Determining whether refrigerant leakage occurs in the indoor unit according to 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; If it is determined that the current refrigerant concentration detected by the refrigerant detection device continues to rise within the preset second time, it is determined that a refrigerant leak occurs in the indoor unit; 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, it is determined that no refrigerant leakage occurs in the indoor unit, and the air conditioner is controlled to restart and resume operation.

6. The control method of an air conditioner according to any one of claims 3 to 5, characterized in that: Determining the maximum temperature difference of the current working environment temperature of the refrigerant detection device within a preset first time includes any of the following determination methods: In the case where the current working environment temperature of the refrigerant detection device is the temperature detected by the first temperature detection module of the indoor unit at a position within a set distance range from the refrigerant detection device, the first determination method is: Determine, within a preset first time, a maximum value of the current working environment temperature of the refrigerant detection device and a minimum value of the current working environment temperature of the refrigerant detection device; Determine a difference between a maximum value of the current working environment temperature of the refrigerant detection device and a minimum value of the current working environment temperature of the refrigerant detection device as a maximum temperature difference of the current working environment temperature of the refrigerant detection device; In the case where the current working environment temperature of the refrigerant detection device is the tube temperature of the indoor heat exchanger of the indoor unit detected by the second temperature detection module of the indoor unit or the indoor environment temperature of the indoor unit detected by the third temperature detection module of the indoor unit, the second determination method is: Determine a maximum value of the tube temperature of the indoor heat exchanger of the indoor unit and a minimum value of the tube temperature of the indoor heat exchanger of the indoor unit within a preset first time; and determine a difference between the maximum value of the tube temperature of the indoor heat exchanger of the indoor unit and the minimum value of the tube temperature of the indoor heat exchanger of the indoor unit, which is recorded as a first difference; Determine a maximum value of the indoor environment temperature of the indoor unit and a minimum value of the indoor environment temperature of the indoor unit within a preset first time; and determining a difference between a maximum value of the indoor ambient temperature of the indoor unit and a minimum value of the indoor ambient temperature of the indoor unit, which is recorded as a second difference; The maximum value of the first difference and the second difference is used as the maximum temperature difference of the current working environment temperature of the refrigerant detection device.

7. A control device 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 the location of the refrigerant detection device itself, which is recorded as the current refrigerant concentration detected by the refrigerant detection device; The control device of the air conditioner comprises: an acquisition unit configured to acquire, after the air conditioner is powered on and when the refrigerant detection device itself is able to work, a current refrigerant concentration detected by the refrigerant detection device; and acquire a current working environment temperature of the refrigerant detection device; a control unit configured to determine whether a 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 the current state of the air conditioner 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 also configured to determine whether a refrigerant leak occurs in the indoor unit based on 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 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; and, if it is determined that a refrigerant leak occurs in the indoor unit, control the air conditioner to execute a preset refrigerant leakage fault protection mechanism.

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

9. A storage medium, characterized in that: The storage medium includes a stored program, wherein when the program is executed, the device where the storage medium is located is controlled to execute the air conditioner control method according to any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the air conditioner control method according to any one of claims 1 to 6 are implemented.

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