Control method, device and equipment of air conditioner heat pump unit and air conditioner heat pump unit

Abstract

The invention belongs to the technical field of refrigeration, and particularly relates to a control method, device and equipment of an air conditioner heat pump unit and the air conditioner heat pump unit. The control method comprises the steps that temperature and pressure data of the two ends of a compressor, temperature and pressure data of the two ends of an electronic expansion valve and environment temperature and pressure data of an outdoor unit and an indoor unit are collected; according to the temperature and pressure data of the two ends of the compressor and the temperature and pressure data of the two ends of the electronic expansion valve, the actual filling amount of each component of a refrigerant in the refrigerating loop is calculated; according to the environment temperature and pressure data of the outdoor unit and the indoor unit, pre-stored standard charging amounts of all components of the refrigerant under the corresponding environment temperature and pressure are searched for; according to the fact that the absolute value of the difference value between the actual charging amount and the standard charging amount is larger than a first threshold value, it is determined that the refrigerating circuit has the refrigerant leakage fault. The leakage state of each component of the refrigerant in the refrigerating circuit can be actively monitored, tiny leakage points can be quickly sensed in time, early warning is carried out, and the safety of an air conditioner heat pump unit is improved.

Description

Technical Field

[0001] The present application relates to the field of refrigeration technology, and more specifically, to a control method, device, equipment and air conditioning heat pump unit. Background Art

[0002] Severe frosting on the outdoor unit of the air-conditioning heat pump unit will lead to a significant decrease in the heat transfer coefficient and a rapid decrease in the heat exchange, resulting in rapid fluctuations in the unit's pressure. For example, under refrigeration conditions, the pressure of the outdoor unit will rise rapidly. The rapid change in refrigerant pressure coupled with factors such as the material of the unit's copper tubes and manufacturing errors will significantly increase the possibility of system leaks. At this time, leakage of flammable refrigerant will cause great safety risks.

[0003] In the traditional combustible leakage control method, the system leakage point is mainly monitored by installing sound, light, electricity, combustible gas sensors or specific organic matter sensors. Among them, the combustible gas sensor has the characteristics of high cost and high precision, and can monitor the state when the lower limit of combustion is reached to ensure the safety of the space where the unit is located. However, the outdoor unit of the air-conditioning heat pump unit is usually in an outdoor environment. Due to the open characteristics of the outdoor environment, the air around the outdoor unit is kept circulating. The installation of traditional combustible gas sensors has measurement conditions. For example, the measurement range of a certain combustible gas sensor is within a straight-line distance of 2m and the air flow rate is required to be below 2m / s. If the wind speed exceeds this speed, the measurement range will be sharply reduced to within 50cm, and the accuracy will be greatly reduced, or even fail. In winter in northern regions, the air flow rate when the wind is strong generally exceeds the flow rate requirement, and the combustible gas alarm cannot completely prevent the refrigerant leakage of the unit. In addition, restricted by the principle of the combustible gas alarm, the measurement effect is very poor in low temperature and high humidity environments, and there is even a risk of failure, which cannot guarantee the stable operation of the air-conditioning heat pump unit and the safety of personnel. Summary of the invention

[0004] The purpose of the present application is to provide a control method, device, equipment and air-conditioning heat pump unit, which can actively monitor the leakage status of refrigerant in the refrigeration circuit, timely and quickly sense tiny leaks and issue warnings, thereby improving the safety of the air-conditioning heat pump unit.

[0005] A first aspect of the present application provides a control method for an air-conditioning heat pump unit. The air-conditioning heat pump unit includes an indoor unit and an outdoor unit connected through a refrigeration circuit. The indoor unit includes a first heat exchanger, and the outdoor unit includes a compressor, a second heat exchanger, and a four-way valve. The four-way valve includes a first interface, a second interface, a third interface, and a fourth interface. The first interface is connected to the first heat exchanger through a first pipeline, the second interface is connected to the exhaust end of the compressor through an exhaust pipeline, the third interface is connected to the suction end of the compressor through a suction pipeline, the fourth interface is connected to one end of the second heat exchanger through a second pipeline, and the other end of the second heat exchanger is connected to the other end of the first heat exchanger through a third pipeline. An electronic expansion valve is provided on the third pipeline. The control method includes: collecting temperature and pressure data at the exhaust end and suction end of the compressor, temperature and pressure data at the suction end and exhaust end of the electronic expansion valve, ambient temperature and pressure data of the outdoor unit, and ambient temperature and pressure data of the indoor unit; calculating the actual filling amount of each component of the refrigerant in the refrigeration circuit according to the temperature and pressure data at the exhaust end and suction end of the compressor and the temperature and pressure data at the suction end and exhaust end of the electronic expansion valve; looking up the standard filling amount of each component of the refrigerant at the corresponding ambient temperature and pressure stored in advance according to the ambient temperature and pressure data of the outdoor unit and the ambient temperature and pressure data of the indoor unit; determining that a refrigerant leakage fault occurs in the refrigeration circuit when the absolute value of the difference between the actual filling amount and the standard filling amount is greater than a first threshold value.

[0006] According to the control method for the air-conditioning heat pump unit provided by the embodiments of the present application, by collecting the temperature and pressure data at the exhaust end and suction end of the compressor, and the temperature and pressure data at the suction end and exhaust end of the electronic expansion valve, calculating the actual filling amount of each component of the refrigerant in the refrigeration circuit, looking up the standard filling amount of each component of the refrigerant at the corresponding ambient temperature and pressure stored in advance according to the ambient temperature and pressure data of the outdoor unit and the ambient temperature and pressure data of the indoor unit, and determining that a refrigerant leakage fault occurs in the refrigeration circuit when the absolute value of the difference between the actual filling amount and the standard filling amount is greater than a first threshold value. Thus, the present application can actively, real-timely, and all-weather monitor the refrigerant leakage fault in the refrigeration circuit. Compared with the passive monitoring scheme in the related art that monitors the system leak points through acoustic-optic sensors, combustible gas sensors, or specific organic matter sensors, the present application can more timely and quickly sense small leak points and give early warnings. Moreover, each temperature and pressure data is monitored by temperature sensors and pressure sensors, and the stability of the temperature sensors and pressure sensors is higher than that of combustible gas alarms or organic matter alarms, and they can stably play their roles in high humidity and low temperature, greatly improving the safety of the air-conditioning heat pump unit.

[0007] The second aspect of the present application provides a control device for an air-conditioning heat pump unit. The air-conditioning heat pump unit includes an indoor unit and an outdoor unit connected through a refrigeration circuit. The indoor unit includes a first heat exchanger, and the outdoor unit includes a compressor, a second heat exchanger, and a four-way valve. The four-way valve includes a first port, a second port, a third port, and a fourth port. The first port is connected to the first heat exchanger through a first pipeline, the second port is connected to the exhaust end of the compressor through an exhaust pipeline, the third port is connected to the suction end of the compressor through a suction pipeline, the fourth port is connected to one end of the second heat exchanger through a second pipeline, and the other end of the second heat exchanger is connected to the other end of the first heat exchanger through a third pipeline. An electronic expansion valve is provided on the third pipeline. The control device includes: a collection module configured to collect the temperature and pressure data of the exhaust end and the suction end of the compressor, the temperature and pressure data of the suction end and the exhaust end of the electronic expansion valve, the ambient temperature and pressure data of the outdoor unit, and the ambient temperature and pressure data of the indoor unit; a storage module configured to pre-store the standard charging amount data of each component of the refrigerant under various ambient temperatures and pressures; and a processing module configured to calculate the actual charging amount of each component of the refrigerant in the refrigeration circuit according to the temperature and pressure data of the exhaust end and the suction end of the compressor and the temperature and pressure data of the suction end and the exhaust end of the electronic expansion valve; find the corresponding standard charging amount data of each component of the refrigerant from the storage module according to the ambient temperature and pressure data of the outdoor unit and the ambient temperature and pressure data of the indoor unit; and determine that a refrigerant leakage fault occurs in the indoor unit or the outdoor unit according to the absolute value of the difference between the actual charging amount and the standard charging amount being greater than a first threshold value.

[0008] The third aspect of the present application provides a control device for an air-conditioning heat pump unit, including: a memory storing computer program instructions; and a processor that implements the control method of the air-conditioning heat pump unit according to the embodiments of the present application when the computer program instructions are executed by the processor.

[0009] The fourth aspect of the present application provides an air-conditioning heat pump unit, including an indoor unit and an outdoor unit connected through a refrigeration circuit, and the control device for the air-conditioning heat pump unit according to the embodiments of the present application. The control device is electrically connected to the indoor unit and the outdoor unit respectively.

[0010] The above description is only an overview of the technical solution of the present application. In order to be able to understand the technical means of the present application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other objects, features, and advantages of the present application more obvious and understandable, the specific embodiments of the present application are specifically described below. Description of the Drawings

[0011] Upon reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered as a limitation of this application. Moreover, throughout the drawings, the same reference numerals are used to denote the same components. Among them:

[0012] Upon reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered as a limitation of this application. Moreover, throughout the drawings, the same reference numerals are used to denote the same components. Among them:

[0013] Figure 1 It is a schematic electrical structure diagram of the air-conditioning heat pump unit in the refrigeration condition according to an embodiment of the present application;

[0014] Figure 2 It is a schematic electrical structure diagram of the air-conditioning heat pump unit in the heating condition according to an embodiment of the present application;

[0015] Figure 3 It is a flowchart of the control method of the air-conditioning heat pump unit according to an embodiment of the present application;

[0016] Figure 4 It is a schematic structural diagram of the control device of the air-conditioning heat pump unit according to an embodiment of the present application.

[0017] The reference numerals in the drawings are represented as follows:

[0018] 100, air-conditioning heat pump unit; 10, control device; 101, acquisition module; 102, storage module; 103, processing module; 104, control module;

[0019] 1, indoor unit; 11, first heat exchanger; 12, auxiliary electric heater; 13, first ambient temperature sensor; 14, first ambient pressure sensor;

[0020] 2, outdoor unit; 20, fan; 21, compressor; 22, second heat exchanger; 221, air pressure sensor; 23, four-way valve; E, first interface; D, second interface; S, third interface; C, fourth interface; 24, second ambient temperature sensor; 25, second ambient pressure sensor; 26, first temperature sensor; 27, first pressure sensor; 28, second temperature sensor; 29, second pressure sensor;

[0021] 3, refrigeration circuit; 31, first pipeline; 32, second pipeline; 33, third pipeline; 34, exhaust pipeline; 35, return air pipeline; 36, first emergency safety pipeline; 37, second emergency safety pipeline;

[0022] 4. Electronic expansion valve; 5. First solenoid valve; 6. Second solenoid valve; 61. Third temperature sensor; 62. Third pressure sensor; 63. Fourth temperature sensor; 64. Fourth pressure sensor; 7. Third solenoid valve; 8. First emergency solenoid valve; 9. Second emergency solenoid valve. Detailed implementation manners

[0023] The exemplary embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present application can be more thoroughly understood and the scope of the present application can be completely conveyed to those skilled in the art.

[0024] It should be understood that the terms used herein are for the purpose of describing specific exemplary embodiments only and are not intended to be limiting. Unless otherwise clearly specified in the context, the singular forms "a", "an", and "the" as used herein may also include the plural forms. The terms "comprising", "including", "containing", and "having" are inclusive and thus specify the presence of the stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring them to be performed in the particular order described or illustrated, unless the order of performance is explicitly stated. It should also be understood that additional or alternative steps may be used.

[0025] Although terms such as first, second, and third may be used herein to describe multiple elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or section from another. Unless otherwise clearly indicated in the context, terms such as "first" and "second" and other numerical terms used herein do not imply an order or sequence. Therefore, the first element, component, region, layer, or section discussed below may be referred to as the second element, component, region, layer, or section without departing from the teachings of the exemplary embodiments.

[0026] For ease of description, spatial relative relationship terms may be used in the text to describe the relationship of one element or feature shown in the figure relative to another element or feature. These relative relationship terms are, for example, "inside", "outside", "inner side", "outer side", "below", "beneath", "above", "over", etc. Such spatial relative relationship terms are intended to include different orientations of the device in use or operation other than the orientations depicted in the figure. For example, if the device in the figure is flipped, an element described as "below" or "beneath" other elements or features will then be oriented as "above" or "over" other elements or features. Thus, the exemplary term "below" can include both upward and downward orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions) and the spatial relative relationship descriptors used in the text are interpreted accordingly.

[0027] Figure 1 The figure is a schematic electrical structure diagram of the air-conditioning heat pump unit according to an embodiment of the present application under a refrigeration condition. Figure 2 The figure is a schematic electrical structure diagram of the air-conditioning heat pump unit according to an embodiment of the present application under a heating condition.

[0028] Refer to Figure 1 and Figure 2 An air-conditioning heat pump unit 100 according to an embodiment of the present application includes an indoor unit 1 and an outdoor unit 2 connected through a refrigeration circuit 3. The indoor unit 1 is installed indoors, and the outdoor unit 2 is installed outdoors. It is used for refrigeration or heating, and transports refrigerant through pipelines. The refrigerant exchanges heat with the indoor air and the outdoor air respectively. The indoor unit 1 is used to deliver cold air or hot air indoors to achieve the effect of cooling or heating.

[0029] Specifically, the indoor unit 1 includes a first heat exchanger 11. A first ambient temperature sensor 13 and a first ambient pressure sensor 14 are also provided in the surrounding environment of the indoor unit 1. The first ambient temperature sensor 13 is used to monitor the ambient temperature of the surrounding environment of the indoor unit 1, and the first ambient pressure sensor 14 is used to monitor the ambient pressure of the surrounding environment of the indoor unit 1.

[0030] The outdoor unit 2 includes a compressor 21, a second heat exchanger 22, and a four-way valve 23. A second ambient temperature sensor 24 and a second ambient pressure sensor 25 are also provided in the surrounding environment of the outdoor unit 2. The second ambient temperature sensor 24 is used to monitor the ambient temperature of the surrounding environment of the outdoor unit 2, and the second ambient pressure sensor 25 is used to monitor the ambient pressure of the surrounding environment of the outdoor unit 2. A first temperature sensor 26 and a first pressure sensor 27 are provided at the exhaust end of the compressor 21, and a second temperature sensor 28 and a second pressure sensor 29 are provided at the suction end of the compressor 21. The first temperature sensor 26 and the first pressure sensor 27 are respectively used to monitor the temperature and pressure at the exhaust end of the compressor 21, and the second temperature sensor 28 and the second pressure sensor 29 are respectively used to monitor the temperature and pressure at the suction end of the compressor 21.

[0031] The four-way valve 23 has a first port E, a second port D, a third port S, and a fourth port C. The first port E is connected to the first heat exchanger 11 through a first pipeline 31, the second port D is connected to the exhaust end of the compressor 21 through an exhaust pipeline 34, the third port S is connected to the suction end of the compressor 21 through a suction pipeline 35, the fourth port C is connected to one end of the second heat exchanger 22 through a second pipeline 32, and the other end of the second heat exchanger 22 is connected to the other end of the first heat exchanger 11 through a third pipeline 33.

[0032] The air-conditioning heat pump unit 100 realizes two working modes: a refrigeration cycle mode and a heating cycle mode through the four-way valve 23.

[0033] As Figure 1 shown, when the four-way valve 23 is powered off, the first port E can be conducted with the third port S, and the second port D is conducted with the fourth port C. The air-conditioning heat pump unit 100 operates normally and enters the refrigeration cycle mode. In the refrigeration cycle mode, after the refrigerant is discharged from the exhaust end of the compressor 21, it flows through the four-way valve 23 to the second heat exchanger 22 of the outdoor unit 2 and the first heat exchanger 11 of the indoor unit 1 in sequence. At this time, the second heat exchanger 22 is used as a condenser to condense the high-temperature and high-pressure refrigerant discharged from the compressor 21, and the first heat exchanger 11 is used as an evaporator to exchange heat between the low-temperature refrigerant and the indoor air, so as to output cold air to the indoor. Then the refrigerant returns to the compressor 21 through the suction end.

[0034] As Figure 2As shown, when the four-way valve 23 is powered on, the first interface E can be connected to the second interface D, and the third interface S is connected to the fourth interface C, and the air conditioning heat pump unit 100 enters the heating cycle mode. In the heating cycle mode, after the refrigerant is discharged from the exhaust end of the compressor 21, it flows to the first heat exchanger 11 and the second heat exchanger 22 in sequence through the four-way valve 23. At this time, the first heat exchanger 11 is used as a condenser, and the high-temperature and high-pressure refrigerant discharged from the exhaust end of the compressor 21 exchanges heat with the first heat exchanger 11, thereby outputting warm air to the room. The second heat exchanger 22 is used as an evaporator, and then the refrigerant flows back to the compressor 21 from the return air end.

[0035] Furthermore, wind pressure sensors 221 are respectively provided on the air inlet side and the air outlet side of the second heat exchanger 22, wherein one wind pressure sensor 221 is used to monitor the wind pressure data on the air inlet side of the second heat exchanger 22, and the other wind pressure sensor 221 is used to monitor the wind pressure data on the air outlet side of the second heat exchanger 22. The actual wind pressure change value can be calculated based on the wind pressure data on the air inlet side and the air outlet side, thereby determining whether the outdoor unit 2 is frosted. Severe frosting of the outdoor unit 2 will lead to a significant decrease in the heat transfer coefficient, a rapid decrease in the heat exchange amount, and rapid fluctuations in the pressure of the air conditioning heat pump unit 100, significantly increasing the possibility of leakage in the system. At this time, the leakage of flammable refrigerant will cause great safety risks. Therefore, by predicting the frosting state of the outdoor unit 2 in advance, the refrigerant leakage failure and the spread of the leakage in the refrigeration circuit 3 can be avoided to the greatest extent.

[0036] Furthermore, the indoor unit 1 further includes an auxiliary electric heater 12 disposed on one side of the first heat exchanger 11. When the air conditioning heat pump unit 100 is in the cooling state, if a refrigerant leakage fault is detected in the refrigeration circuit 3, the auxiliary electric heater 12 is started to heat the residual refrigerant in the indoor unit 1, so that the residual refrigerant in the indoor unit 1 flows into the outdoor unit 2.

[0037] Further, an electronic expansion valve 4 is provided in the third pipeline 33, and a first electromagnetic valve 5 is provided in the first pipeline 31. A third temperature sensor 61 and a third pressure sensor 62 are provided at the suction end of the electronic expansion valve 4, and a fourth temperature sensor 63 and a fourth pressure sensor 64 are provided at the discharge end of the electronic expansion valve 4. A second electromagnetic valve 6 is further provided between the electronic expansion valve 4 in the third pipeline 33 and the second heat exchanger 22, and a third electromagnetic valve 7 is provided on the second pipeline 32. Among them, the third temperature sensor 61 and the third pressure sensor 62 are respectively used to monitor the temperature and pressure at the suction end of the electronic expansion valve 4, and the fourth temperature sensor 63 and the fourth pressure sensor 64 are respectively used to monitor the temperature and pressure at the discharge end of the electronic expansion valve 4. The first electromagnetic valve 5 is used to control the on-off of the first pipeline 31. When the first electromagnetic valve 5 is opened, the refrigerant can flow from the indoor unit 1 to the outdoor unit. The second electromagnetic valve 6 is used to control the on-off of the third pipeline 33. When the second electromagnetic valve 6 is opened, the refrigerant can enter the indoor unit 1. The third electromagnetic valve 7 is used to control the on-off of the second pipeline 32.

[0038] Further, a first emergency safety pipeline 36 is provided between the exhaust pipeline 34 and the second pipeline 32, and a first emergency electromagnetic valve 8 is provided in the first emergency safety pipeline 36; a second emergency safety pipeline 37 is provided between the return air pipeline 35 and the third pipeline 33, and a second emergency electromagnetic valve 9 is provided in the second emergency safety pipeline 37. Among them, the first emergency electromagnetic valve 8 is used to control the on-off of the first emergency safety pipeline 36, and the second emergency electromagnetic valve 9 is used to control the on-off of the second emergency safety pipeline 37.

[0039] When the air-conditioning heat pump unit 100 is in the heating condition, if a refrigerant leakage fault is detected in the refrigeration circuit 3, the second electromagnetic valve 6 and the first electromagnetic valve 5 are turned off, the second emergency electromagnetic valve 9 of the indoor unit 1 is opened, and at the same time the compressor 21 is started. Through the second emergency safety pipeline 37, the refrigerant in the indoor unit 1 can be quickly pumped into the compressor 21, avoiding the leakage of the combustible refrigerant in the indoor unit 1 to the indoor where people are active and endangering the safety of people. At this time, the first emergency electromagnetic valve 8 is open, which can ensure that the refrigerant discharged from the compressor 21 is discharged into the second heat exchanger 22 through the first emergency safety pipeline 36. At the same time, the third electromagnetic valve 7 is closed to prevent the short circuit of the return air pipeline 35 and the exhaust pipeline 34 of the compressor 21, resulting in poor suction of the refrigerant from the indoor unit 1. Since the opening and closing of the four-way valve 23 require a certain period of time, usually the pipeline function can be switched only after the high and low pressures in the system are balanced. Therefore, setting the first emergency safety pipeline 36 and the second emergency safety pipeline 37 is the fastest and safest method to suck out the combustible refrigerant in the indoor unit 1.

[0040] Figure 3 It is a flow block diagram of the control method of the air-conditioning heat pump unit according to the embodiment of the present application.

[0041] Please refer toFigures 1 to 3 , an embodiment of the present application provides a control method for an air-conditioning heat pump unit, including the following steps S1 to S4.

[0042] Step S1: Collect the temperature and pressure data of the exhaust end and the suction end of the compressor 21, the temperature and pressure data of the suction end and the exhaust end of the electronic expansion valve 4, the ambient temperature and pressure data of the outdoor unit 2, and the ambient temperature and pressure data of the indoor unit 1;

[0043] Step S2: Calculate the actual filling amount of each component of the refrigerant in the refrigeration circuit 3 according to the temperature and pressure data of the exhaust end and the suction end of the compressor 21 and the temperature and pressure data of the suction end and the exhaust end of the electronic expansion valve 4;

[0044] Step S3: Look up the standard filling amount of each component of the refrigerant under the corresponding ambient temperature and pressure stored in advance according to the ambient temperature and pressure data of the outdoor unit 2 and the ambient temperature and pressure data of the indoor unit 1;

[0045] Step S4: Determine that a refrigerant leakage fault occurs in the refrigeration circuit 3 according to the absolute value of the difference between the actual filling amount and the standard filling amount being greater than the first threshold.

[0046] In this embodiment, a first temperature sensor 26 and a first pressure sensor 27 are arranged at the exhaust end of the compressor 21, and a second temperature sensor 28 and a second pressure sensor 29 are arranged at the suction end of the compressor 21. The first temperature sensor 26 and the first pressure sensor 27 are respectively used to monitor the temperature and pressure of the exhaust end of the compressor 21, and the second temperature sensor 28 and the second pressure sensor 29 are respectively used to monitor the temperature and pressure of the suction end of the compressor 21. A third temperature sensor 61 and a third pressure sensor 62 are arranged at the suction end of the electronic expansion valve 4, and a fourth temperature sensor 63 and a fourth pressure sensor 64 are arranged at the exhaust end of the electronic expansion valve 4. The third temperature sensor 61 and the third pressure sensor 62 are respectively used to monitor the temperature and pressure of the suction end of the electronic expansion valve 4, and the fourth temperature sensor 63 and the fourth pressure sensor 64 are respectively used to monitor the temperature and pressure of the exhaust end of the electronic expansion valve 4.

[0047] At the same time, a first ambient temperature sensor 13 and a first ambient pressure sensor 14 are also arranged in the surrounding environment of the indoor unit 1. The first ambient temperature sensor 13 is used to monitor the ambient temperature of the surrounding environment of the indoor unit 1, and the first ambient pressure sensor 14 is used to monitor the ambient pressure of the surrounding environment of the indoor unit 1. A second ambient temperature sensor 24 and a second ambient pressure sensor 25 are also arranged in the surrounding environment of the outdoor unit 2. The second ambient temperature sensor 24 is used to monitor the ambient temperature of the surrounding environment of the outdoor unit 2, and the second ambient pressure sensor 25 is used to monitor the ambient pressure of the surrounding environment of the outdoor unit 2.

[0048] Since combustible refrigerants generally consist of multiple components, if there is a leak point in the air-conditioning heat pump unit 100, the leakage rates of the refrigerants in the system are different. When the combustible gas alarm is above a certain threshold, it can only measure whether the refrigerant leaks or not, but the temperature sensors, pressure sensors and the database corresponding to the physical properties can judge the leakage curve and leakage intensity. The environmental temperature-pressure - unit temperature, pressure, and refrigerant charge curves corresponding to big data are drawn according to the initial component ratio of the combustible refrigerant. If there is a leak point in the system, the leakage rate of a certain refrigerant in the system is faster, while the leakage rate of the refrigerant of other components is relatively slower. Then, through the horizontal comparison of the four measuring points: the first temperature sensor 26 and the first pressure sensor 27 at the high-pressure gas phase of the refrigerant, the fourth temperature sensor 63 and the fourth pressure sensor 64 at the high-pressure liquid phase, the second temperature sensor 28 and the second pressure sensor 29 at the low-pressure gas phase, and the third temperature sensor 61 and the third pressure sensor 62 at the low-pressure gas-liquid two-phase, it is possible to quickly and sensitively sense the change in the refrigerant charge of multiple components in the system.

[0049] According to the temperature and pressure values measured at the above four measuring points, calculate the actual refrigerant charge of each component in the refrigeration circuit 3. According to the environmental temperature and pressure data of the outdoor unit 2 and the environmental temperature and pressure data of the indoor unit 1, look up the standard refrigerant charge of each component under the corresponding environmental temperature and pressure stored in the big database. If the difference between the actual refrigerant charge and the standard refrigerant charge is greater than the first threshold, it is determined that a refrigerant leakage fault has occurred in the refrigeration circuit 3. For example, after calculation, the actual refrigerant charge of a certain component is 80 Kg, the standard refrigerant charge is 100 Kg, the absolute value of the difference between the two is 20 Kg, and the first threshold is 10 Kg, then it can be determined that a refrigerant leakage fault has occurred in the refrigeration circuit 3. The size of the first threshold depends on the specific application scenario and test data and will not be elaborated here.

[0050] Therefore, in this embodiment, by comparing the environmental and pressure values stored in the large database, the actual charging amount changes of each component of the multi-component mixed refrigerant can be quickly sensed. There is also a correction function for the refrigerant components. If there are differences between the initially installed refrigerant components and the standard refrigerant components, the system can also report errors and make corrections. Therefore, the method for judging the system leak point in this application can actively, real-timely, and all-weather monitor the refrigerant leakage fault, and can give a warning when there is a change in the charging amount due to a slight change in the components. It is mainly used to diagnose the leakage state of the refrigerant system itself. Compared with the passive monitoring scheme of the related technology that monitors the system leak point through sound and light sensors, combustible gas or specific organic matter sensors, it senses faster and more timely, can quickly sense even a tiny leak point, does not rely on high-cost and high-precision sensors such as sound and light or combustible gas alarm sensors, and the combustible gas sensor can only monitor the state when the lower explosion limit of the combustible refrigerant exceeds a certain threshold. Moreover, the stability of the temperature sensor and the pressure sensor is higher than that of the combustible gas alarm and the organic matter component alarm, etc., and it can stably function in high humidity and low temperature, greatly improving the safety of the unit.

[0051] According to the control method of the air-conditioning heat pump unit provided by the embodiment of the present application, by collecting the temperature and pressure data at the exhaust end and the suction end of the compressor 21, and the temperature and pressure data at the suction end and the exhaust end of the electronic expansion valve 4, the actual charging amount of each component of the refrigerant in the refrigeration circuit 3 is calculated. According to the environmental temperature and pressure data of the outdoor unit 2 and the environmental temperature and pressure data of the indoor unit 1, the standard charging amount of each component of the refrigerant under the corresponding environmental temperature and pressure stored is searched. When the absolute value of the difference between the actual charging amount and the standard charging amount is greater than the first threshold, it is determined that a refrigerant leakage fault occurs in the indoor unit 1 or the outdoor unit 2. Therefore, the present application can actively, real-timely, and all-weather monitor the refrigerant leakage fault. Compared with the passive monitoring scheme of the related technology that monitors the system leak point through sound and light sensors, combustible gas or specific organic matter sensors, the present application can more timely and quickly sense and warn of tiny leak points, and each temperature and pressure data is monitored by a temperature sensor and a pressure sensor. The stability of the temperature sensor and the pressure sensor is higher than that of the combustible gas alarm or the organic matter alarm, and it can stably function in high humidity and low temperature, greatly improving the safety of the air-conditioning heat pump unit 100.

[0052] Further, in step S2, calculating the actual charging amount of each component of the refrigerant in the refrigeration circuit 3 includes:

[0053] Calculate the filling amounts of the refrigerant components in each segmented pipeline of the refrigeration circuit 3 according to the phase states of the refrigerant in the multiple segmented pipelines. The sum of the filling amounts of the refrigerant components in each segmented pipeline is the actual filling amount of the refrigerant components. Among them, the multiple segmented pipelines include an exhaust pipeline 34, a second pipeline 32, the internal pipeline of a second heat exchanger 22, a third pipeline 33, the internal pipeline of a first heat exchanger 11, a first pipeline 31, and a return air pipeline 35. The refrigerant in the exhaust pipeline 34, the first pipeline 31, and the return air pipeline 35 is a gaseous refrigerant, the refrigerant in the third pipeline 33 is a liquid refrigerant, and the refrigerant in the internal pipelines of the first heat exchanger 11 and the second heat exchanger 22 is a gas-liquid mixed refrigerant.

[0054] In this embodiment, the calculation method for the filling amounts of the refrigerant components in the multiple segmented pipelines of the refrigeration circuit 3 is as follows:

[0055] For the refrigerant in the exhaust pipeline 34, the first pipeline 31, and the return air pipeline 35 being a gaseous refrigerant, the calculation method for the filling amounts of the refrigerant components is described by the ideal gas state equation according to the change relationship among the pressure (P), density (ρ), and temperature (T) of the gas, that is, PV = nRT. Among them, P represents pressure, V represents volume, n represents the amount of substance, R is the ideal gas constant, and T is temperature. Substitute the volume V with the ratio of mass m and density ρ (i.e., V = m / ρ), then P = ρRT / M, where M is the molar mass. For a certain amount of gas (i.e., the amount of substance n remains unchanged), its pressure P is proportional to the product of density ρ and temperature T. That is, if the temperature T remains unchanged, then the pressure P is proportional to the density ρ; if the density ρ remains unchanged, then the pressure P is proportional to the temperature T. The product of the density ρ of the refrigerant components and the volume of each segmented pipeline is the filling amount of the refrigerant components.

[0056] For the refrigerant in the third pipeline 33 being a liquid refrigerant, the calculation method for the filling amounts of the refrigerant components is that the product of the density ρ of the refrigerant components and the volume of the third pipeline 33 is the filling amount of the refrigerant components.

[0057] For the refrigerant in the internal pipelines of the first heat exchanger 11 and the second heat exchanger 22 being a gas-liquid mixed refrigerant, the calculation methods for the filling amounts of the refrigerant components are the same. Taking the second heat exchanger 22 as an example below, the calculation method for the filling amounts of the refrigerant components is referred to as follows:

[0058] According to the exhaust pressure at the exhaust end of the compressor 21, the saturation temperature corresponding to the exhaust pressure of the compressor 21 is calculated, that is, the condensation temperature. According to the suction pressure at the suction end of the compressor 21, the saturation temperature corresponding to the suction pressure of the compressor 21 is calculated, that is, the evaporation temperature. Then, according to the compressor flow coefficient, condensation temperature and evaporation temperature related to the frequency, exhaust pressure, suction pressure and suction temperature of the compressor, the charging amount m of each refrigerant component is calculated as

[0059] k1 + k2*Te + k3*Tc + k4*Te 2 + k5*Te*Tc + K6*Tc 2 + k7*Te 3 + k8*Te 2 *Tc + k9*Te*Tc 2 + k10*Tc 3 . Among them, k1 to k10 are 10 coefficients related to the frequency, exhaust pressure pd, suction pressure ps and suction temperature Ts of the compressor. Te is the saturation temperature corresponding to the suction pressure of the compressor 21, and Tc is the saturation temperature corresponding to the exhaust pressure pd of the compressor 21, and Te = b1 / (ln(ps)b2) b3, Tc = b1 / (ln(pd) b2) b3;

[0060] The pressure drop of the exhaust pipe 34 of the compressor 21 is dp1 = f1(m, Td, pd) = A1*m*exp(B1*Tc)*(Td - Tc),

[0061] The heat leakage Q1 of the exhaust pipe 34 of the compressor 21 is Q1 = f2(m, Td, T0) = (Td - T0)*A2*m;

[0062] The inlet pressure p1 of the second heat exchanger 22 is p1 = pd - dp1;

[0063] The inlet temperature T1 of the second heat exchanger 22 is T1 = Td - Q1 / (m*B2*Tds);

[0064] The saturation temperature T1s corresponding to the inlet pressure of the second heat exchanger 22 is T1s = b1 / (ln(p1)b2)b3;

[0065] Among them, B1 to B2, b1 to b3 are refrigerant physical property parameters related to the refrigerant type. f1(m, Td, pd) is a function related to the exhaust temperature Td, exhaust pressure pd of the compressor and the charging amount m of each refrigerant component. A1 to A2 are parameters related to the structure of the exhaust pipe 34; f2(m, Td, T0) is a function related to the ambient temperature of the outdoor unit 2, the exhaust temperature Td of the compressor 21 and the charging amount m of each refrigerant component. The values of each parameter are determined according to the specific application scenario and will not be elaborated.

[0066] It can be understood that other calculation methods can also be used to calculate the filling amounts of the respective components of the refrigerant in the internal pipelines of the first heat exchanger 11 and the second heat exchanger 22, and all are within the protection scope of this application.

[0067] Furthermore, the control method of the air-conditioning heat pump unit according to the embodiment of this application further includes:

[0068] Step S5: According to the refrigerant leakage fault occurring in the refrigeration circuit 3 under the refrigeration condition, control the first interface E and the third interface S of the four-way valve 23 to be conducted, and the second interface D and the fourth interface C to be conducted, close the second solenoid valve 6, turn on the auxiliary electric heater 12 to heat the residual refrigerant in the indoor unit 1, and at the same time turn on the first solenoid valve 5 and start the compressor 21, so that the residual refrigerant in the indoor unit 1 flows into the outdoor unit 2.

[0069] As Figure 1 shown, when the air-conditioning heat pump unit 100 is in the refrigeration condition, the four-way valve 23 is in the power-off state, the first interface E and the third interface S are conducted, and the second interface D and the fourth interface C are conducted. After detecting the refrigerant leakage fault in the refrigeration circuit 3 according to the foregoing control method, the second solenoid valve 6 entering the indoor unit will be automatically shut off, the auxiliary electric heater 12 of the indoor unit 1 will be turned on, the first solenoid valve 5 leading from the indoor unit 1 to the outdoor unit 2 will be opened. The auxiliary electric heater 12 can heat the residual refrigerant in the indoor unit 1, so that the internal residual refrigerant flows into the outdoor unit 2 faster, ensuring the safety of the indoor unit 1. At the same time, the compressor 21 is started, and the residual refrigerant in the indoor unit 1 is quickly pumped out into the outdoor unit 2 through the pipeline.

[0070] Furthermore, the control method of the air-conditioning heat pump unit according to the embodiment of this application further includes:

[0071] Step S6: According to the refrigerant leakage fault occurring in the refrigeration circuit 3 under the heating condition, control the third interface S and the fourth interface C of the four-way valve 23 to be conducted, and the first interface E and the second interface D to be conducted, close the second solenoid valve 6 and the third solenoid valve 7, turn on the first emergency solenoid valve 8, start the compressor 21, so that the refrigerant in the indoor unit 1 flows into the outdoor unit 2 through the first emergency safety pipeline 36, and at the same time close the first solenoid valve 5, turn on the second emergency solenoid valve 9, so that the refrigerant discharged by the compressor 21 enters the outdoor unit 2 through the second emergency safety pipeline 37.

[0072] As Figure 2As shown in the figure, when the air-conditioning heat pump unit 100 is in the heating mode, the four-way valve 23 is in the energized state. The first interface E can be conducted with the second interface D, and the third interface S is conducted with the fourth interface C. After detecting a refrigerant leakage fault in the refrigeration circuit 3 according to the foregoing control method, the second solenoid valve 6 that enters the indoor unit 1 during normal refrigerant operation and the first solenoid valve 5 that exits the indoor unit 1 are shut off, and the second emergency solenoid valve 9 of the indoor unit 1 is opened. At the same time, the compressor 21 is started, and the refrigerant in the indoor unit 1 is quickly pumped into the compressor 21 through the provided second emergency safety pipeline 37, so as to prevent the combustible refrigerant in the indoor unit 1 from leaking into the room where people are active, endangering the safety of people. At this time, the first emergency solenoid valve 8 is open, which can ensure that the refrigerant discharged by the compressor 21 is discharged into the second heat exchanger 22 through the first emergency safety pipeline 36. At the same time, the third solenoid valve 7 is closed to prevent the suction pipe 35 and the discharge pipe 34 of the compressor 21 from being short-circuited, resulting in poor suction of the refrigerant from the indoor unit 1. Since the opening and closing of the four-way valve 23 takes a certain amount of time, usually the pipeline function can be switched only after the high and low pressures in the system are balanced, so the first emergency safety pipeline 36 and the second emergency safety pipeline 37 are the fastest and safest methods to suck out the combustible refrigerant in the indoor unit 1.

[0073] In addition, if a refrigerant leakage fault occurs in the outdoor unit 2, the fan 20 of the outdoor unit 2 is turned on, and the first solenoid valve 5, the second solenoid valve 6 and the second emergency solenoid valve 9 are closed. The fan 20 blows away the combustible refrigerant through forced air convection, ensuring that the combustible refrigerant is quickly reduced to a safe concentration without accumulation. Closing the second solenoid valve 6, the first solenoid valve 5 and the second emergency solenoid valve 9 that enter the indoor unit 1 can prevent the combustible refrigerant from entering the indoor unit 1 and ensure the safety of indoor personnel.

[0074] In addition, serious frosting of the outdoor unit 2 of the air-conditioning heat pump unit 100 will cause a significant reduction in the heat transfer coefficient and a rapid decrease in the heat exchange capacity, resulting in a rapid pressure fluctuation of the air-conditioning heat pump unit 100. For example, in the refrigeration mode, the pressure of the outdoor unit 2 will rise rapidly. According to research, the sharp change of the refrigerant pressure coupled with factors such as the copper tube material and manufacturing error of the unit will significantly increase the possibility of leakage points in the system. At this time, the leakage of the combustible refrigerant will pose a great safety risk. Therefore, the control method of the air-conditioning heat pump unit in the embodiment of the present application can predict the frosting state of the outdoor unit 2 in advance, and avoid the refrigerant leakage fault and the spread of leakage in the refrigeration circuit 3 to the greatest extent.

[0075] Specifically, the control method of the air-conditioning heat pump unit in the embodiment of the present application further includes the following steps S8 to S12.

[0076] Step S8: Collect the wind pressure data on the inlet side and the outlet side of the second heat exchanger 22;

[0077] Step S9: Calculate the actual wind pressure change value according to the wind pressure data;

[0078] Step S10: Search for the pre-stored standard wind pressure change value according to the ambient temperature and pressure data of the outdoor unit 2;

[0079] Step S11: Determine that the second heat exchanger 22 is in a frosting state according to the absolute value of the difference between the actual wind pressure change value and the standard wind pressure change data being greater than the second threshold;

[0080] Step S12: Defrost the second heat exchanger 22 according to the fact that the second heat exchanger 22 is in a frosting state.

[0081] In this embodiment, by respectively arranging wind pressure sensors 221 on the air inlet side and the air outlet side of the second heat exchanger 22 of the outdoor unit 2 to monitor the wind pressure data on the air inlet side and the air outlet side, calculating the wind pressure change value according to the wind pressure data, establishing a large database of frosting and wind pressure through the wind pressure change as the basis for self-diagnosis of the frosting state of the outdoor unit 2, and determining that the second heat exchanger 22 is in a frosting state according to the absolute value of the difference between the wind pressure change value and the standard wind pressure change data being greater than the second threshold. The size of the second threshold is determined according to specific application scenarios and test data, and will not be elaborated here.

[0082] Thus, when it is monitored that the second heat exchanger 22 of the outdoor unit 2 is in a frosting state in this embodiment, the defrosting program of the second heat exchanger 22 can be quickly started for defrosting, avoiding frosting of the second heat exchanger 22, obtaining better heating efficiency, and at the same time being able to ensure the long-life stable operation of the outdoor unit 2, and maximizing the avoidance of refrigerant leakage faults and the spread of leakage in the refrigeration circuit 3.

[0083] Figure 4 It is a structural schematic diagram of the control device of the air-conditioning heat pump unit according to the embodiment of the present application.

[0084] Refer to Figure 1 、 Figure 2 and Figure 4 The embodiment of the present application provides a control device 10 of an air-conditioning heat pump unit, including an acquisition module 101, a storage module 102, and a processing module 103.

[0085] The acquisition module 101 is configured to acquire the temperature and pressure data at the exhaust end and the suction end of the compressor 21, the temperature and pressure data at the suction end and the exhaust end of the electronic expansion valve 4, the ambient temperature and pressure data of the outdoor unit 2, and the ambient temperature and pressure data of the indoor unit 1.

[0086] The storage module 102 is configured to pre-store the standard filling amount data of each component of the refrigerant under various ambient temperatures and ambient pressures.

[0087] The processing module 103 is configured to calculate the actual filling amount of each component of the refrigerant in the refrigeration circuit 3 according to the temperature and pressure data of the exhaust end and the suction end of the compressor 21 and the temperature and pressure data of the suction end and the exhaust end of the electronic expansion valve 4; search for the standard filling amount data of each component of the refrigerant corresponding to the ambient temperature and pressure data of the outdoor unit 2 and the ambient temperature and pressure data of the indoor unit 1; and determine that a refrigerant leakage fault occurs in the indoor unit 1 or the outdoor unit 2 according to the absolute value of the difference between the actual filling amount and the standard filling amount being greater than a first threshold value.

[0088] Further, the processing module 103 calculates the actual filling amount of each component of the refrigerant in the refrigeration circuit 3 by: respectively calculating the filling amount of each component of the refrigerant in each segmented pipeline of the refrigeration circuit 3 according to the phase state of the refrigerant in the plurality of segmented pipelines of the refrigeration circuit 3, and the sum of the filling amounts of each component of the refrigerant in each segmented pipeline is the actual filling amount of each component of the refrigerant. Among them, the plurality of segmented pipelines include an exhaust pipeline 34, a second pipeline 32, the internal pipeline of the second heat exchanger 22, a third pipeline 33, the internal pipeline of the first heat exchanger 11, a first pipeline 31, and a suction pipeline 35. The refrigerant in the exhaust pipeline 34, the first pipeline 31, and the suction pipeline 35 is gaseous refrigerant, the refrigerant in the third pipeline 33 is liquid refrigerant, and the refrigerant in the internal pipelines of the first heat exchanger 11 and the second heat exchanger 22 is gas-liquid mixed refrigerant. Among them, the calculation method of the filling amount of each component of the refrigerant in the plurality of segmented pipelines of the refrigeration circuit 3 is as described above and will not be elaborated.

[0089] Further, the control device 10 further includes a control module 104, and the control module 104 is configured to, according to a refrigerant leakage fault occurring in the refrigeration circuit 3 under a refrigeration condition, control the first interface E and the third interface S of the four-way valve 23 to be conducted, and the second interface D and the fourth interface C to be conducted, close the second solenoid valve 6, turn on the auxiliary electric heater 12 to heat the residual refrigerant in the indoor unit 1; turn on the first solenoid valve 5 and start the compressor 21 so that the refrigerant in the indoor unit 1 flows into the outdoor unit 2.

[0090] Further, the control module 104 is further configured to, according to a refrigerant leakage fault occurring in the refrigeration circuit 3 under a heating condition, control the third interface S and the fourth interface C of the four-way valve 23 to be conducted, and the first interface E and the second interface D to be conducted; close the second solenoid valve 6 and the third solenoid valve 7, turn on the first emergency solenoid valve 8, start the compressor 21 so that the refrigerant in the indoor unit 1 flows into the outdoor unit 2 through the first emergency safety pipeline 36, close the first solenoid valve 5, and turn on the second emergency solenoid valve 9 so that the refrigerant discharged by the compressor 21 enters the outdoor unit 2 through the second emergency safety pipeline 37.

[0091] Further, the control module 104 is further configured to turn on the fan of the outdoor unit 2 and turn off the first solenoid valve 5, the second solenoid valve 6, and the second emergency solenoid valve 9 according to a refrigerant leakage fault occurring in the outdoor unit 2.

[0092] Further, the acquisition module 101 is further configured to acquire the air pressure data on the inlet side and the outlet side of the second heat exchanger 22; the storage module 102 is further configured to pre-store the standard air pressure change value data under various environmental temperatures and pressures;

[0093] The processing module 103 is further configured to calculate the actual air pressure change value according to the air pressure data, look up the corresponding standard air pressure change value data according to the environmental temperature and pressure data of the outdoor unit 2, and determine that the second heat exchanger 22 is in a frosting state according to the absolute value of the difference between the actual air pressure change value and the standard air pressure change data being greater than a second threshold;

[0094] The control device 10 further includes a control module 104, and the control module 104 is configured to defrost the second heat exchanger 22 according to the second heat exchanger 22 being in a frosting state.

[0095] It can be understood that the control device 10 of the air-conditioning heat pump unit provided in the embodiment of the present application is the execution subject of the control method of the foregoing air-conditioning heat pump unit. For the specific execution manners and beneficial effects of each module, reference may be made to the content of the control method of the foregoing air-conditioning heat pump unit, which will not be elaborated herein.

[0096] In addition, the embodiment of the present application further provides a control device for an air-conditioning heat pump unit. The control device is electrically connected to the indoor unit 1 and the outdoor unit 2 of the air-conditioning heat pump unit of the embodiment of the present application respectively. The control device includes:

[0097] A memory storing computer program instructions;

[0098] A processor, when the computer program instructions are executed by the processor, implementing the control method of the air-conditioning heat pump unit of the embodiment of the present application.

[0099] In addition, the embodiment of the present application further provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of implementing the control method of the air-conditioning heat pump unit of the embodiment of the present application can be realized.

[0100] All or part of the processes in the control method of the air-conditioning heat pump unit in the above embodiments of the present application can be completed by instructing relevant hardware through a computer program. This computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of the control methods of the above various air-conditioning heat pump units can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file or some intermediate form, etc. The computer-readable medium can at least include: any entity or device that can carry the computer program code to the air-conditioning system, recording medium, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium. For example, USB flash drive, mobile hard disk, magnetic disk or optical disc, etc.

[0101] Reference to "embodiment" in this text means that the specific features, structures or characteristics described in connection with the embodiment may be included in at least one embodiment of the present application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment each time, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0102] As mentioned above, only the preferred specific embodiments of the present application are described, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A control method for an air-conditioning heat pump unit, characterized in that, The air-conditioning heat pump unit includes an indoor unit and an outdoor unit connected through a refrigeration circuit. The indoor unit includes a first heat exchanger. The outdoor unit includes a compressor, a second heat exchanger, and a four-way valve. The four-way valve includes a first interface, a second interface, a third interface, and a fourth interface. The first interface is connected to the first heat exchanger through a first pipeline. The second interface is connected to the exhaust end of the compressor through an exhaust pipeline. The third interface is connected to the suction end of the compressor through a suction pipeline. The fourth interface is connected to one end of the second heat exchanger through a second pipeline. The other end of the second heat exchanger is connected to the other end of the first heat exchanger through a third pipeline. An electronic expansion valve is provided on the third pipeline. The control method of the air-conditioning heat pump unit includes: Collecting the temperature and pressure data of the exhaust end and the suction end of the compressor, the temperature and pressure data of the suction end and the exhaust end of the electronic expansion valve, the ambient temperature and pressure data of the outdoor unit, and the ambient temperature and pressure data of the indoor unit; Calculating the actual filling amount of each component of the refrigerant in the refrigeration circuit according to the temperature and pressure data of the exhaust end and the suction end of the compressor and the temperature and pressure data of the suction end and the exhaust end of the electronic expansion valve; Searching for the standard filling amount of each component of the refrigerant under the corresponding ambient temperature and pressure stored in advance according to the ambient temperature and pressure data of the outdoor unit and the ambient temperature and pressure data of the indoor unit; Determining that a refrigerant leakage fault occurs in the refrigeration circuit according to the absolute value of the difference between the actual filling amount and the standard filling amount being greater than a first threshold.

2. The control method of the air-conditioning heat pump unit according to claim 1, characterized in that The calculating the actual filling amount of each component of the refrigerant in the refrigeration circuit includes: Calculating the filling amount of each component of the refrigerant in each of the segmented pipelines according to the phase state of the refrigerant in the multiple segmented pipelines of the refrigeration circuit. The sum of the filling amounts of each component of the refrigerant in each of the segmented pipelines is the actual filling amount of each component of the refrigerant. Among them, the multiple segmented pipelines include the exhaust pipeline, the second pipeline, the internal pipeline of the second heat exchanger, the third pipeline, the internal pipeline of the first heat exchanger, the first pipeline, and the suction pipeline. The refrigerant in the exhaust pipeline, the first pipeline, and the suction pipeline is gaseous refrigerant, the refrigerant in the third pipeline is liquid refrigerant, and the refrigerant in the internal pipelines of the first heat exchanger and the second heat exchanger is gas-liquid mixed refrigerant.

3. The control method of the air-conditioning heat pump unit according to claim 1 or 2, characterized in that, The indoor unit further includes an auxiliary electric heater provided on one side of the first heat exchanger. A second solenoid valve is further provided between the electronic expansion valve of the third pipeline and the second heat exchanger. A first solenoid valve is provided on the first pipeline. The control method further includes: According to the refrigerant leakage failure of the refrigeration circuit under refrigeration conditions, the first interface of the four-way valve is controlled to be connected to the third interface, and the second interface is controlled to be connected to the fourth interface, the second solenoid valve is closed, and the auxiliary electric heater is turned on to heat the residual refrigerant in the indoor unit. At the same time, the first solenoid valve is opened and the compressor is started to allow the residual refrigerant in the indoor unit to flow into the outdoor unit.

4. The control method of the air-conditioning heat pump unit according to claim 1 or 2, characterized in that A first emergency safety pipeline is provided between the exhaust pipeline and the second pipeline, and a first emergency solenoid valve is provided on the first emergency safety pipeline; a second emergency safety pipeline is provided between the return air pipeline and the third pipeline, and a second emergency solenoid valve is provided on the second emergency safety pipeline, and a third solenoid valve is provided on the second pipeline, and a second solenoid valve is further provided between the electronic expansion valve of the third pipeline and the second heat exchanger, and the first pipeline is provided with a first solenoid valve, and the control method further includes: According to a refrigerant leakage failure in the refrigeration circuit under heating conditions, the third interface of the four-way valve is controlled to be connected to the fourth interface, and the first interface is controlled to be connected to the second interface, the second solenoid valve and the third solenoid valve are closed, the first emergency solenoid valve is opened, and the compressor is started so that the refrigerant in the indoor unit flows into the outdoor unit through the first emergency safety pipeline. At the same time, the first solenoid valve is closed and the second emergency solenoid valve is opened so that the refrigerant discharged from the compressor enters the outdoor unit through the second emergency safety pipeline.

5. The control method of the air-conditioning heat pump unit according to claim 1, characterized in that, The control method further comprises: Collecting wind pressure data on the air inlet side and the air outlet side of the second heat exchanger; Calculate the actual wind pressure change value according to the wind pressure data; Searching for pre-stored standard wind pressure change value data according to the ambient temperature and pressure data of the outdoor unit; According to the absolute value of the difference between the actual wind pressure change value and the standard wind pressure change data being greater than a second threshold, determining that the second heat exchanger is in a frosting state; According to the second heat exchanger being in a frosted state, the second heat exchanger is defrosted.

6. A control device for an air-conditioning heat pump unit, characterized in that, The air conditioning heat pump unit comprises an indoor unit and an outdoor unit connected through a refrigeration circuit, the indoor unit comprises a first heat exchanger, the outdoor unit comprises a compressor, a second heat exchanger and a four-way valve, the four-way valve comprises a first interface, a second interface, a third interface and a fourth interface, the first interface is connected to the first heat exchanger through a first pipeline, the second interface is connected to the exhaust end of the compressor through an exhaust pipeline, the third interface is connected to the return end of the compressor through a return pipeline, the fourth interface is connected to one end of the second heat exchanger through a second pipeline, the other end of the second heat exchanger is connected to the other end of the first heat exchanger through a third pipeline, the third pipeline is provided with an electronic expansion valve, and the control device of the air conditioning heat pump unit comprises: A collection module, configured to collect temperature and pressure data at the exhaust end and the suction end of the compressor, temperature and pressure data at the suction end and the exhaust end of the electronic expansion valve, ambient temperature and pressure data of the outdoor unit, and ambient temperature and pressure data of the indoor unit; A storage module, configured to pre-store standard refrigerant charge data for each component at various ambient temperatures and pressures; A processing module, configured to calculate the actual refrigerant charge for each component in the refrigeration circuit based on the temperature and pressure data at the exhaust end and the suction end of the compressor and the temperature and pressure data at the suction end and the exhaust end of the electronic expansion valve, and to look up the corresponding standard refrigerant charge for each component from the storage module based on the ambient temperature and pressure data of the outdoor unit and the ambient temperature and pressure data of the indoor unit; determine that a refrigerant leakage fault has occurred in the refrigeration circuit if the absolute value of the difference between the actual refrigerant charge and the standard refrigerant charge is greater than a first threshold.

7. The control device of the air-conditioning heat pump unit according to claim 6, characterized in that, The processing module calculating the actual refrigerant charge for each component in the refrigeration circuit includes: calculating the refrigerant charge for each component of each of the segmented pipelines according to the phase state of the refrigerant in the multiple segmented pipelines of the refrigeration circuit, and the sum of the refrigerant charges for each component of each of the segmented pipelines is the actual refrigerant charge for each component, where the multiple segmented pipelines include the exhaust pipeline, the second pipeline, the internal pipeline of the second heat exchanger, the third pipeline, the internal pipeline of the first heat exchanger, the first pipeline, and the suction pipeline, and the refrigerant in the exhaust pipeline, the first pipeline, and the suction pipeline is gaseous refrigerant, the refrigerant in the third pipeline is liquid refrigerant, and the refrigerant in the internal pipelines of the first heat exchanger and the second heat exchanger is a gas-liquid mixed refrigerant.

8. The control device of the air-conditioning heat pump unit according to claim 6 or 7, characterized in that The indoor unit further includes an auxiliary electric heater disposed on one side of the first heat exchanger, a second solenoid valve is further disposed between the electronic expansion valve of the third pipeline and the second heat exchanger, and a first solenoid valve is disposed on the first pipeline; The control device further includes a control module, configured to, according to a refrigerant leakage fault occurring in the refrigeration circuit under a refrigeration condition, control the first interface and the third interface of the four-way valve to be conducted, and the second interface and the fourth interface to be conducted; close the second solenoid valve, turn on the auxiliary electric heater to heat the residual refrigerant in the indoor unit; turn on the first solenoid valve and start the compressor so that the refrigerant in the indoor unit flows into the outdoor unit.

9. The control device of the air-conditioning heat pump unit according to claim 6 or 7, characterized in that, A first emergency safety pipeline is disposed between the exhaust pipeline and the second pipeline, and a first emergency solenoid valve is disposed on the first emergency safety pipeline; a second emergency safety pipeline is disposed between the suction pipeline and the third pipeline, and a second emergency solenoid valve is disposed on the second emergency safety pipeline, a third solenoid valve is disposed on the second pipeline, a second solenoid valve is further disposed between the electronic expansion valve of the third pipeline and the second heat exchanger, and a first solenoid valve is disposed on the first pipeline; The control module is further configured to, according to a refrigerant leakage fault occurring in the refrigeration circuit under a heating condition, control the third interface and the fourth interface of the four-way valve to be conducted, and the first interface and the second interface to be conducted, close the second solenoid valve and the third solenoid valve, open the first emergency solenoid valve, and start the compressor, so that the refrigerant in the indoor unit flows into the outdoor unit through the first emergency safety pipeline, close the first solenoid valve, and open the second emergency solenoid valve, so that the refrigerant discharged by the compressor enters the outdoor unit through the second emergency safety pipeline.

10. The control device of the air-conditioning heat pump unit according to claim 6, characterized in that, The acquisition module is further configured to acquire the air pressure data on the air inlet side and the air outlet side of the second heat exchanger; The storage module is further configured to pre-store the standard air pressure change value data under various environmental temperatures and pressures; The processing module is further configured to calculate the actual air pressure change value according to the air pressure data, find the corresponding standard air pressure change data according to the environmental temperature and pressure data of the outdoor unit, and determine that the second heat exchanger is in a frosting state according to the absolute value of the difference between the actual air pressure change value and the standard air pressure change data being greater than a second threshold; The control device further includes a control module, and the control module is configured to defrost the second heat exchanger according to the second heat exchanger being in a frosting state.

11. A control device for an air-conditioning heat pump unit, characterized in that, Comprising: A memory storing computer program instructions; A processor, when the computer program instructions are executed by the processor, implementing the control method of the air-conditioning heat pump unit according to any one of claims 1 to 5.

12. An air-conditioning heat pump unit, characterized in that, Comprising an indoor unit and an outdoor unit connected through a refrigeration circuit, and the control device of the air-conditioning heat pump unit according to claim 11, wherein the control device is electrically connected to the indoor unit and the outdoor unit respectively.

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