Multi-air conditioning system, fault location identification method and fault diagnosis model training method

Abstract

Some embodiments of the present disclosure provide a multi-air conditioning system, a fault location identification method, and a fault diagnosis model training method. The multi-air conditioning system includes an outdoor unit, a plurality of indoor units, a plurality of electronic expansion valves, and a controller. A gas pipe and a liquid pipe are connected to each of the indoor units among the plurality of indoor units. The plurality of electronic expansion valves are provided in the liquid pipes to which the corresponding indoor units are connected. The controller is configured to acquire characteristic data of each of the indoor units among the plurality of indoor units when a failure of the electronic expansion valve occurs in the multi-air conditioning system. The characteristic data of each indoor unit includes a temperature difference between a temperature value of a liquid pipe connected to the indoor unit and a temperature value of a gas pipe connected to the indoor unit. The controller is configured to determine an abnormal indoor unit among the plurality of indoor units according to the characteristic data of each indoor unit among the plurality of indoor units. The controller is configured to determine an electronic expansion valve corresponding to the abnormal indoor unit as a faulty electronic expansion valve.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority from Chinese patent application having application number 202210386517.3 filed on April 11, 2022, and Chinese patent application having application number 202210682549.8 filed on June 16, 2022, the entire disclosures of which are incorporated herein by reference.

[0002] The present invention relates to the field of air conditioning technology, and in particular to a multi-air conditioning system, a fault location method and a fault diagnosis model training method. [Background technology]

[0003] A multi-air conditioning system includes an outdoor unit and a plurality of indoor units, and adjusts the temperature of a plurality of indoor spaces in which the plurality of indoor units are located. Because the multi-air conditioning system has a large number of components, when a failure occurs in the multi-air conditioning system, it is difficult to quickly identify the failed component, which reduces the efficiency of identifying the failure location of the multi-air conditioning system. Summary of the Invention

[0004] In one aspect, some embodiments of the present disclosure provide a multi-air conditioning system. The multi-air conditioning system includes an outdoor unit, a plurality of indoor units, a plurality of electronic expansion valves, and a controller. A gas pipe and a liquid pipe are connected to each of the indoor units among the plurality of indoor units, so that the indoor units communicate with the outdoor unit via the gas pipe and the liquid pipe. The plurality of electronic expansion valves correspond to the plurality of indoor units. The plurality of electronic expansion valves are provided in the liquid pipes to which the corresponding indoor units are connected, and are configured to control the refrigerant output amount or the refrigerant input amount of the corresponding indoor unit.

[0005] The controller is configured to acquire characteristic data of each indoor unit among the indoor units when a failure of an electronic expansion valve occurs in the multi-air conditioning system. The characteristic data of each indoor unit includes a temperature difference between a temperature value of a liquid pipe connected to the indoor unit and a temperature value of a gas pipe connected to the indoor unit. The controller is configured to determine an abnormal indoor unit among the indoor units according to the characteristic data of each indoor unit among the indoor units. The controller is configured to determine an electronic expansion valve corresponding to the abnormal indoor unit as a faulty electronic expansion valve.

[0006] In another aspect, some embodiments of the present disclosure provide a method for identifying a fault location in a multi-air conditioning system. The multi-air conditioning system includes an outdoor unit, a plurality of indoor units, and a plurality of electronic expansion valves. A gas pipe and a liquid pipe are connected to each of the indoor units among the plurality of indoor units, so that the indoor units communicate with the outdoor unit via the gas pipe and the liquid pipe. The plurality of electronic expansion valves correspond to the plurality of indoor units. The plurality of electronic expansion valves are provided in the liquid pipes to which the corresponding indoor units are connected, and are configured to control the refrigerant output amount or the refrigerant input amount of the corresponding indoor unit.

[0007] The method includes, when a failure of an electronic expansion valve occurs in a multi-air conditioning system, acquiring characteristic data of each indoor unit among a plurality of indoor units, the characteristic data of each indoor unit including a temperature difference between a temperature value of a liquid pipe connected to the indoor unit and a temperature value of a gas pipe connected to the indoor unit, determining an abnormal indoor unit among the plurality of indoor units according to the characteristic data of each indoor unit among the plurality of indoor units, and determining the electronic expansion valve corresponding to the abnormal indoor unit as a failed electronic expansion valve.

[0008] In yet another aspect, some embodiments of the present disclosure provide a fault diagnosis model training method for a multi-air conditioning system, the training method includes: obtaining normal values ​​and fault values ​​of a plurality of operating data of a first multi-air conditioning system; determining a first feature offset space of the first multi-air conditioning system based on the normal values ​​and fault values ​​of the plurality of operating data of the first multi-air conditioning system, the first feature offset space including a difference between a fault value and a normal value of each of the plurality of operating data of the first multi-air conditioning system; correcting the first feature offset space based on a difference between the normal values ​​of the plurality of operating data of the first multi-air conditioning system and the normal values ​​of the plurality of operating data of the second multi-air conditioning system to obtain a second feature offset space of the second multi-air conditioning system; determining fault values ​​of the plurality of operating data of the second multi-air conditioning system based on the normal values ​​and the second feature offset space of the plurality of operating data of the second multi-air conditioning system; and training a fault diagnosis model based on the normal values ​​and fault values ​​of the plurality of operating data of the second multi-air conditioning system.

[0009] In the following, in order to more clearly explain the technical solutions according to the present disclosure, the drawings used in some embodiments of the present disclosure will be briefly described, but the drawings in the following description are only some drawings of some embodiments of the present disclosure, and those skilled in the art can obtain other drawings based on these drawings. In addition, the drawings in the following description can be regarded as schematic diagrams, and do not limit the actual dimensions of the products, the actual flow of the methods, the actual timing of the signals, etc. according to the embodiments of the present disclosure. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a structural diagram of a multi-air conditioning system according to some embodiments. [Diagram 2] FIG. 2 is another structural diagram of a multi-air conditioning system according to some embodiments. [Diagram 3] FIG. 2 is a structural diagram of a controller according to some embodiments. [Figure 4]FIG. 2 is a diagram illustrating an interaction scheme between a controller and a terminal device according to some embodiments. [Diagram 5] FIG. 2 is an interface diagram of a terminal device according to some embodiments. [Figure 6] 2 is a flowchart of a fault location method for a multi-air conditioning system according to some embodiments. [Figure 7] FIG. 2 is another interface diagram of a terminal device according to some embodiments. [Figure 8] FIG. 11 is yet another interface diagram of a terminal device according to some embodiments. [Figure 9] FIG. 2 is a location diagram of a first temperature sensor and a second temperature sensor according to some embodiments. [Figure 10] 4 is another flowchart of a fault location method for a multi-air conditioning system according to some embodiments. [Figure 11] 4 is yet another flowchart of a fault location method for a multi-air conditioning system according to some embodiments. [Figure 12] FIG. 11 is yet another interface diagram of a terminal device according to some embodiments. [Figure 13] 4 is a flowchart of a method for training a fault diagnosis model for a multi-air conditioning system according to some embodiments. [Figure 14] 4 is another flowchart of a method for training a fault diagnosis model of a multi-air conditioning system according to some embodiments. [Figure 15] 1 is a structural diagram of a fault diagnosis model training method according to some embodiments; [Figure 16] 1 is yet another flowchart of a method for training a fault diagnosis model of a multi-air conditioning system according to some embodiments. [Figure 17] 1 is yet another flowchart of a method for training a fault diagnosis model of a multi-air conditioning system according to some embodiments. [Figure 18] FIG. 2 is a diagram illustrating the structure of an autoencoder model according to some embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, some embodiments of the present disclosure will be described clearly and completely with reference to the drawings. Of course, the embodiments described herein are only a part of the embodiments of the present disclosure, and are not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments that can be obtained by those skilled in the art shall be within the scope of protection of the present disclosure.

[0012] Unless otherwise indicated by the context, in the present specification and claims, the term "comprise" and other forms, such as the third person singular "comprises" and the present participle form "comprising" should be interpreted in an open, inclusive sense, i.e., "including but not limited to." In the description of the specification, the terms "one embodiment," "some embodiments," "exemplary embodiments," "examples," "specific examples," "some examples," and the like, are intended to indicate that a particular feature, structure, material, or characteristic associated with this embodiment or the examples is included in at least one embodiment or example of the present disclosure. General expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, a particular feature, structure, material, or characteristic described may be included in any one or more embodiments or examples in any suitable manner.

[0013] In the following, the terms "first" and "second" are for descriptive purposes only and should not be understood as indicating or implying the relative importance or quantity of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more than two.

[0014] In describing some embodiments, the terms "coupled" and "connected" and expressions derived therefrom may be used. The term "connected" should be understood in a broad sense, for example, "connected" may be a fixed connection, a removable connection, or integral, and may be a direct connection or an indirect connection through an intermediate medium. The term "coupled" indicates, for example, that two or more components have direct physical or electrical contact with each other. The terms "coupled" or "communicatively coupled" may also mean that two or more components are not in direct contact with each other but still cooperate or interact with each other. The embodiments disclosed herein are not necessarily limited to the contents of this specification.

[0015] "A and / or B" includes the three combinations of A only, B only, and a combination of A and B.

[0016] In this specification, the use of "disposed to" is intended to be open and inclusive language and does not exclude devices adapted or arranged to perform additional tasks or steps.

[0017] Additionally, the use of "based on" denotes open and inclusive language, as a process, step, calculation, or other action performed "based on" one or more recited conditions or values ​​may, in fact, be based on additional conditions or more than the recited values.

[0018] In some embodiments of the present disclosure, a multi-air conditioning system 10 is provided. As shown in FIG. 1, the multi-air conditioning system 10 includes an outdoor unit 11, a plurality of electronic expansion valves 12, a plurality of indoor units 13, and a controller 14 (not shown in FIG. 1). The outdoor unit 11 may be, for example, a device that is attached to an area such as the outside of a wall of a house or a rooftop in the multi-air conditioning system 10. The outdoor unit 11 is mainly used to compress a refrigerant and circulate the refrigerant in the multi-air conditioning system 10. The refrigerant is a substance that easily absorbs heat and becomes a gas, and further easily releases heat and becomes a liquid. The indoor unit 13 is, for example, a device that is attached indoors in the multi-air conditioning system 10. The indoor unit 13 is mainly used to transport cool air or hot air to an indoor space in which the indoor unit 13 is located, thereby regulating the temperature of the indoor space.

[0019] In some embodiments, a gas pipe 15 and a liquid pipe 16 are connected to each indoor unit among the multiple indoor units 13, so that the indoor unit communicates with the outdoor unit 11 via the gas pipe 15 and the liquid pipe 16. The gas pipe 15 is configured to transport a gaseous refrigerant or a two-phase refrigerant (a refrigerant in which gaseous and liquid states coexist) between the outdoor unit 11 and the indoor unit 13, and the liquid pipe 16 is configured to transport a liquid refrigerant or a two-phase refrigerant between the outdoor unit 11 and the indoor unit 13. The gas pipe 15 and the liquid pipe 16 may be collectively referred to as a duct.

[0020] In some examples, the multiple electronic expansion valves 12 correspond to multiple indoor units 13. The multiple electronic expansion valves 12 are provided in liquid pipes 16 to which the corresponding indoor units 13 are connected, and are configured to control the refrigerant output amount or refrigerant input amount of the corresponding indoor units 13.

[0021] The multiple electronic expansion valves 12 may be provided independently of the multiple indoor units 13 (as shown in FIG. 1 ), or may be provided belonging to the multiple indoor units 13. In the following embodiment, an example in which the multiple electronic expansion valves 12 are provided independently of the multiple indoor units 13 will be described as an example.

[0022] In some embodiments, the outdoor unit 11 includes a compressor 111, an outdoor heat exchanger 112, a gas-liquid separator 113, a four-way valve 114, and an outdoor fan 115. The exhaust port of the compressor 111 communicates with a D end of the four-way valve 114, and the intake port of the compressor 111 communicates with an exhaust port of the gas-liquid separator 113. The intake port of the gas-liquid separator 113 communicates with an S end of the four-way valve 114. The C end of the four-way valve 114 communicates with a first end of the outdoor heat exchanger 112, and the E end of the four-way valve 114 communicates with each gas pipe 15. The second end of the outdoor heat exchanger 112 communicates with each liquid pipe 16.

[0023] In some embodiments, each of the indoor units 13 includes an indoor heat exchanger 131, an indoor fan 132, an air outlet 133, and a return air outlet 134. A first end of the indoor heat exchanger 131 communicates with a corresponding gas pipe 15, and a second end of the indoor heat exchanger 131 communicates with a corresponding liquid pipe 16. The air outlet 133 and the return air outlet 134 communicate with the indoor heat exchanger 131 via a blowing duct and a return air duct, respectively.

[0024] It should be noted that the structure shown in Fig. 1 is an exemplary structure of the multi-air conditioning system 10, and the multi-air conditioning system 10 may include more, fewer, or different components than those shown in Fig. 1. For example, the outdoor unit 11 may further include an outdoor fan motor for driving the operation of the outdoor fan 115, and the indoor unit 13 may further include a display and an indoor fan motor for driving the operation of the indoor fan 132. If the indoor unit 13 includes a display, the display may be configured to display the temperature of the indoor space in which the indoor unit 13 is located, and / or may be configured to display the operating status of the multi-air conditioning system 10, etc.

[0025] 2 , the controller 14 is coupled to the compressor 111, the four-way valve 114, and the outdoor fan 115 in the outdoor unit 11, coupled to the plurality of electronic expansion valves 12, and coupled to the indoor fans 132 in the plurality of indoor units 13. The controller 14 is configured to control the operating states of each component coupled to the controller 14.

[0026] The controller 14 is further coupled with a plurality of temperature sensors and a plurality of pressure sensors to obtain temperature and pressure values ​​of a plurality of components in the multi-air conditioning system 10. The installation manner of the plurality of temperature sensors and the plurality of pressure sensors will be described in the following embodiment.

[0027] The controller 14 is further coupled to a communicator 109 to establish a communication connection with another device (e.g., a terminal device) and transmit and receive communication signals via the communicator 109. Exemplarily, the communicator 109 may include a radio frequency (RF) device, a cellular device, a wireless network communication technology (Wi-Fi) device, a global positioning system (GPS) device, and the like.

[0028] In some examples, the controller 14 refers to a device that can instruct the multi-air conditioning system 10 to execute a control command by generating an operation control signal according to an instruction operation code and a timing signal. Exemplarily, the controller 14 may be a central processing unit (CPU), a general-purpose processor, a network processor (NP), a digital signal processing (DSP), a microprocessor, a microcontroller, a programmable logic device (PLD), or any combination thereof. The controller 14 may also be a device having other processing capabilities, such as a circuit, device, or software module, but the embodiments of the present disclosure are not limited thereto.

[0029] 3, the controller 14 includes an outdoor controller 141 and an indoor controller 142. The outdoor controller 141 includes a first memory 1411 and is configured to control the outdoor unit 11 to perform related operations. The indoor controller 142 includes a second memory 1421 and is configured to control the indoor units 13 and the electronic expansion valves to perform related operations. There is a wired or wireless communication connection between the indoor controller 142 and the outdoor controller 141. The outdoor controller 141 and the indoor controller 142 may be installed in association with the outdoor unit 11 and the indoor unit 13, respectively, or may be installed independently of the outdoor unit 11 and the indoor unit 13.

[0030] 3 is an exemplary structure of the controller 14. For example, the outdoor controller 141 and the indoor controller 142 may be integrated into one controller. The first memory 1411 and the second memory 1421 may also be integrated into one memory.

[0031] In some embodiments, the first memory 1411 and the second memory 1421 are configured to store application programs and data. The outdoor controller 141 and the indoor controller 142 execute various functions and data processing of the multi-air conditioning system 10 by executing the application programs and data stored in the first memory 1411 and the second memory 1421, respectively. Exemplarily, the first memory 1411 and the second memory 1421 may include a high-speed random access memory and may further include a non-volatile memory. The first memory 1411 and the second memory 1421 are, for example, a magnetic disk storage device, a flash memory device, etc.

[0032] In some embodiments, a user may control the operation state of the multi-air conditioning system 10 through a device that has established a communication connection with the controller 14. Exemplarily, as shown in Fig. 4, a communication connection exists between the controller 14 and a user's terminal device 300. The communication connection may be realized using various wired or wireless communication technologies, such as Ethernet, Universal Serial Bus (USB), FireWire, any cellular network communication technology (3G / 4G / 5G), Bluetooth, Wi-Fi, Near Field Communication (NFC), or any other suitable communication technology.

[0033] The terminal device 300 may be, for example, a remote control, a mobile phone, a tablet computer, a personal computer (PC), a personal digital assistant (PDA), a smart watch, a wearable electronic device, an augmented reality (AR) device, a virtual reality (VR) device, a robot, etc. In FIG. 4 and the following embodiments, the terminal device 300 is illustratively described as a mobile phone, but the present disclosure does not limit the specific form of the terminal device 300.

[0034] In this embodiment, as shown in Fig. 5, a management interface 301 of the multi-air conditioning system 10 is displayed on the terminal device 300. The management interface 301 includes a first button 302 for managing the operation state of the multi-air conditioning system 10. In response to a user's click operation on the first button 302 in the management interface 301, the terminal device 300 pops up an operation state drop-down selection box 303 in the management interface 301. In response to an operation state selection operation performed by the user in the operation state drop-down selection box 303, the terminal device 300 transmits an operation command corresponding to the selection operation to the multi-air conditioning system 10, and causes the multi-air conditioning system 10 to operate according to the operation state selected by the user.

[0035] In some embodiments, the above-mentioned multi-air conditioning system 10 operates in a cooling operation state to lower the temperature of the indoor space. In the cooling operation state, the controller 14 controls the compressor 111 to start operating, and controls the four-way valve 114 to communicate between the D terminal and the C terminal, and between the S terminal and the E terminal.

[0036] In this way, the compressor 111 starts compressing the refrigerant, and circulates the refrigerant in the multi-air conditioning system 10. Exemplarily, the compressor 111 compresses the gaseous refrigerant into a high-temperature, high-pressure gaseous refrigerant, and the compressed refrigerant reaches a first end of the outdoor heat exchanger 112 through the D and C ends of the four-way valve 114, and flows into the outdoor heat exchanger 112. The high-temperature, high-pressure gaseous refrigerant is liquefied into a low-temperature, low-pressure liquid refrigerant in the outdoor heat exchanger 112, and then reaches second ends of the indoor heat exchangers 131 through the second end of the outdoor heat exchanger 112, the liquid pipe 16, and the electronic expansion valves 12, and flows into the indoor heat exchangers 131. In any one of the indoor units 13, the low-temperature, low-pressure liquid refrigerant is vaporized into a gaseous refrigerant in the indoor heat exchanger 131 of the indoor unit, absorbing the heat around the indoor heat exchanger 131, lowering the temperature of the gas inside the indoor unit, and transporting the gas after the temperature drop to the outside of the indoor unit through the air outlet 133 of the indoor unit, thereby achieving the effect of lowering the temperature of the indoor space. The vaporized gaseous refrigerant then passes through the first end of the indoor heat exchanger 131 and the gas pipe 15 to reach the four-way valve 114, and reaches the intake port of the gas-liquid separator 113 through the E end and S end of the four-way valve 114. In the process of being transported from the indoor heat exchanger 131 to the gas-liquid separator 113, the gaseous refrigerant may condense to produce a liquid, and the gas-liquid separator 113 separates the liquid and then inputs the gaseous refrigerant into the compressor 111 to realize the circulating use of the refrigerant.

[0037] In some other embodiments, the above-mentioned multi-air conditioning system 10 operates in a heating operation state to increase the temperature of the indoor space. Unlike the above-mentioned cooling operation state, in the heating operation state, the controller 14 controls the four-way valve 114 so that the D terminal and the E terminal communicate with each other, and the S terminal and the C terminal communicate with each other.

[0038] In this way, the high-temperature, high-pressure gaseous refrigerant obtained after the compressor 111 performs the compression process is input from the gas pipe 15 to the indoor heat exchangers 131 via the D and E ends of the four-way valve 114. In any one of the indoor units 13, the high-temperature, high-pressure gaseous refrigerant is liquefied into a low-temperature, low-pressure liquid refrigerant in the indoor heat exchanger 131 of the indoor unit, thereby releasing heat to the surroundings of the indoor heat exchanger 131, increasing the temperature of the gas inside the indoor unit, and transporting the heated gas to the outside of the indoor unit through the air outlet 133 of the indoor unit, thereby increasing the temperature of the indoor space. Then, the low-temperature, low-pressure liquid refrigerant flows out from the second end of the indoor heat exchanger 131 and enters the outdoor heat exchanger 112 via the electronic expansion valves 12 and the liquid pipe 16. The low-temperature, low-pressure liquid refrigerant is vaporized into a gaseous refrigerant in the outdoor heat exchanger 112 , then transported to the gas-liquid separator 113 via the C terminal and S terminal of the four-way valve 114 , and then returned to the compressor 111 .

[0039] In the above-mentioned cooling operation state or heating operation state, the outdoor fan 115 is configured to start operating under the control of the controller 14 and to exhaust the amount of heat generated by the outdoor heat exchanger 112 liquefying the refrigerant or the amount of cold generated by vaporizing the refrigerant from the outdoor unit 11, and the indoor fan 132 is configured to start operating under the control of the controller 14 and to exhaust the amount of cold generated by the indoor heat exchanger 131 vaporizing the refrigerant or the amount of heat generated by liquefying the refrigerant from the indoor unit 13, and to adjust the temperature of the indoor space in which the indoor unit 13 is located.

[0040] In some embodiments, the return air port 134 of the indoor unit 13 is configured to transport gas outside the indoor unit 13 to the inside of the indoor unit 13, whereby the gas is cooled or heated inside the indoor unit 13 through the indoor heat exchanger 131, and then transported to the outside of the indoor unit 13 through the air outlet 133. In this way, the gas in the indoor space in which the indoor unit 13 is located can be cooled or heated cyclically, thereby improving the temperature-cooling efficiency or temperature-raising efficiency of the multi-air conditioning system 10.

[0041] When the multi-air conditioning system 10 operates in a cooling operation state, the outdoor heat exchanger 112 may be called a condenser, and the indoor heat exchanger 131 may be called an evaporator. When the multi-air conditioning system 10 operates in a heating operation state, the outdoor heat exchanger 112 may be called an evaporator, and the indoor heat exchanger 131 may be called a condenser. The pressure value at the exhaust port of the compressor 111 may be called an exhaust pressure value, or a condensation pressure value or a high pressure value. The pressure value at the intake port of the compressor 111 may be called an intake pressure value, or an evaporation pressure value or a low pressure value.

[0042] In some embodiments, the electronic expansion valve 12 has a function of expanding and reducing the pressure of the refrigerant flowing through the electronic expansion valve 12, and can adjust the flow rate of the refrigerant in the duct. When the opening degree (degree of opening) of the electronic expansion valve 12 is reduced, the refrigerant flow rate through the electronic expansion valve 12 is reduced. When the opening degree of the electronic expansion valve 12 is increased, the refrigerant flow rate through the electronic expansion valve 12 is increased. For example, when the multi-air conditioning system 10 is in a cooling operation state, the multiple electronic expansion valves 12 are located on the refrigerant input side of the corresponding indoor units 13, and in this case, the multiple electronic expansion valves 12 control the refrigerant input amount of the corresponding indoor units 13. When the multi-air conditioning system 10 is in a heating operation state, the multiple electronic expansion valves 12 are located on the refrigerant output side of the corresponding indoor units 13, and in this case, the multiple electronic expansion valves 12 control the refrigerant output amount of the corresponding indoor units 13.

[0043] As described in the Background Art, in the related art, when a failure occurs in an electronic expansion valve in a multi-air conditioning system 10, a professional maintenance person must observe and analyze the electronic expansion valves 12 in the entire multi-air conditioning system 10, identify the faulty electronic expansion valve, and repair or replace the faulty electronic expansion valve, thereby eliminating the failure of the electronic expansion valve in the multi-air conditioning system 10. Therefore, the multi-air conditioning system 10 in the related art has low efficiency in identifying the failure location, and the degree of automation of the failure location efficiency is low.

[0044] In response to the above technical problems existing in the related art, the inventors of the present disclosure have discovered the following through research. When multiple electronic expansion valves 12 operate normally, the temperature difference between the temperature value of the liquid pipe 16 connected to any one of the indoor units and the temperature value of the gas pipe 15 connected to the indoor unit is smaller than a certain threshold. When a failure of an electronic expansion valve occurs in the multi-air conditioning system 10 (for example, when the electronic expansion valve 12 does not open normally), the temperature difference between the temperature value of the liquid pipe 16 connected to the indoor unit 13 corresponding to the failed electronic expansion valve and the temperature value of the gas pipe 15 connected to the indoor unit is larger than the above-mentioned certain threshold. Therefore, by monitoring the characteristic data during operation of multiple indoor units 13 (for example, the temperature values ​​of the liquid pipe 16 and the gas pipe 15 connected to the same indoor unit 13), it may be possible to determine whether a failure has occurred in multiple electronic expansion valves 12.

[0045] Based on the above technical idea, in some embodiments of the present disclosure, a multi-air conditioning system 10 is provided. When a failure of an electronic expansion valve occurs in the multi-air conditioning system 10, the controller 14 in the multi-air conditioning system 10 may obtain characteristic data of the multiple indoor units 13 in the multi-air conditioning system 10, identify an abnormal indoor unit among the multiple indoor units 13 according to the characteristic data, determine the electronic expansion valve 12 corresponding to the abnormal indoor unit as a faulty electronic expansion valve, and complete the identification of the faulty electronic expansion valve. In this way, after a failure of an electronic expansion valve occurs in the multi-air conditioning system 10, a professional maintenance person does not need to manually identify the multiple electronic expansion valves 12 based on personal experience, but can identify the faulty electronic expansion valve, thereby improving the degree of automation of the fault location identification performed on the multi-air conditioning system 10 and improving the efficiency of identifying the location of the faulty electronic expansion valve in the multi-air conditioning system 10.

[0046] The process in which the controller 14 executes the fault location method will now be described by way of example, mainly with reference to the drawings.

[0047] In some embodiments, as shown in FIG. 6, the controller 14 is configured to execute the following steps S101 to S103.

[0048] S101, when a failure occurs in an electronic expansion valve in the multi-air conditioning system 10, characteristic data of each indoor unit among the plurality of indoor units 13 is obtained.

[0049] The characteristic data of each indoor unit includes the temperature difference between the temperature value of the liquid pipe 16 connected to the indoor unit and the temperature value of the gas pipe 15 connected to the indoor unit.

[0050] For example, the temperature difference may be a value obtained by subtracting the temperature value of the gas pipe 15 connected to the indoor unit from the temperature value of the liquid pipe 16 connected to the indoor unit. Alternatively, the temperature difference may be a value obtained by subtracting the temperature value of the liquid pipe 16 connected to the indoor unit from the temperature value of the gas pipe 15 connected to the indoor unit.

[0051] In some embodiments, the user may instruct the multi-air conditioning system 10 to turn on the fault detection function and fault location identification function via a device that has established a communication connection with the controller 14, so that the controller 14 starts to detect whether a fault has occurred in the electronic expansion valve and identifies the faulty electronic expansion valve. Note that the method by which the controller 14 detects whether a fault has occurred in the electronic expansion valve will be described in the following embodiments.

[0052] Taking the device as an example that is a terminal device 300, as shown in Figs. 7 and 8, the management interface 301 of the terminal device 300 includes a second button 304 for turning on or off the fault detection function of the multi-air conditioning system 10, and a third button 306 for turning on or off the fault location identification function of the multi-air conditioning system 10. When the fault detection function (or the fault location identification function) of the multi-air conditioning system 10 is in an off state, the second button 304 (or the third button 306) is in a first display state 3041 (or a third display state 3061). When the fault detection function (or the fault location identification function) of the multi-air conditioning system 10 is in an on state, the second button 304 (or the third button 306) is in a second display state 3042 (or a fourth display state 3062). For example, when the second button 304 is in the first display state 3041, in response to a user's click operation on the second button 304, the terminal device 300 may instruct the controller 14 to turn on the fault detection function by transmitting a command to the controller 14. After the fault detection function is turned on, the controller 14 may instruct the terminal device 300 to switch the display state of the second button 304 to the second display state 3042 by transmitting a command to the terminal device 300.

[0053] In some examples, when it is detected that the multi-air conditioning system 10 has a failure of the electronic expansion valve, the controller 14 may cause the terminal device 300 to display a prompt box 305 as shown in FIG. 8 by transmitting an instruction to the terminal device 300 via the communication device 109. Exemplarily, the prompt message in the prompt box 305 is "A failure of the electronic expansion valve has been detected in the multi-air conditioning system. Do you want to perform failure location identification immediately?", and presents the user with a choice of whether to turn on the failure location identification function. For example, in response to the user's clicking operation on the "OK" button in the prompt box 305, the terminal device 300 may instruct the controller 14 to turn on the failure location identification function by transmitting an instruction to the controller 14. After the failure location identification function is turned on, the controller 14 may instruct the terminal device 300 to switch the display state of the third button 306 from the third display state 3061 to the fourth display state 3062 by transmitting an instruction to the terminal device 300.

[0054] In some other embodiments, the multi-air conditioning system 10 may automatically turn on the fault detection and fault location functions after a set time of operation. Illustratively, the set time may be preset by a user or manufacturer.

[0055] After the fault location identification function is turned on, the controller 14 starts acquiring characteristic data of multiple indoor units.

[0056] In some examples, as shown in Fig. 2, the multi-air conditioning system 10 includes a plurality of first temperature sensors 101 and a plurality of second temperature sensors 102, which detect the temperature values ​​of the liquid pipes 16 connected to the plurality of indoor units 13 and the temperature values ​​of the gas pipes 15 connected to the plurality of indoor units 13. As shown in Fig. 9, the plurality of first temperature sensors 101 correspond to the indoor heat exchangers 131 of the plurality of indoor units 13, and are provided in the gas pipes 15 connected to the corresponding indoor heat exchangers 131, thereby detecting the temperature values ​​of the corresponding gas pipes 15. The plurality of second temperature sensors 102 correspond to the indoor heat exchangers 131 of the plurality of indoor units 13, and are provided in the liquid pipes 16 to which the corresponding indoor heat exchangers 131 are connected, thereby detecting the temperature values ​​of the corresponding liquid pipes 16. The controller 14 is coupled to a plurality of first temperature sensors 101 and a plurality of second temperature sensors 102, and acquires the temperature difference between the temperature value of the liquid pipe 16 connected to each indoor unit among the plurality of indoor units 13 and the temperature value of the gas pipe 15 connected to the indoor unit.

[0057] In some embodiments, the characteristic data of each indoor unit may further include at least one of the exhaust pressure value of the compressor 111, the intake pressure value of the compressor 111, the exhaust temperature value of the compressor 111, the intake temperature value of the compressor 111, the outlet temperature value of the air outlet 133 of the indoor unit, or the return air temperature value of the return air outlet 134 of the indoor unit. In this embodiment, the multi-air conditioning system 10 detects each of the above characteristic data by including a plurality of other temperature sensors and a plurality of pressure sensors in addition to the above-mentioned plurality of first temperature sensors 101 and the plurality of second temperature sensors 102.

[0058] 2, the multi-air conditioning system 10 includes a first pressure sensor 107 and a second pressure sensor 108. The first pressure sensor 107 is provided at an exhaust port of the compressor 111 and configured to detect a discharge pressure value of the compressor 111. The second pressure sensor 108 is provided at an intake port of the compressor 111 and configured to detect an intake pressure value of the compressor 111. The controller 14 is coupled to the first pressure sensor 107 and the second pressure sensor 108 to obtain the exhaust pressure value and the intake pressure value.

[0059] In some examples, the multi-air conditioning system 10 includes a third temperature sensor 103, a fourth temperature sensor 104, a plurality of fifth temperature sensors 105, and a plurality of sixth temperature sensors 106. The third temperature sensor 103 is provided at an exhaust port of the compressor 111 and configured to detect an exhaust temperature value of the compressor 111. The fourth temperature sensor 104 is provided at an intake port of the compressor 111 and configured to detect an intake temperature value of the compressor 111. The plurality of fifth temperature sensors 105 correspond to the plurality of indoor units 13 and are provided at the air outlets 133 of the corresponding indoor units 13 to detect the air outlet temperature value of the air outlet 133. The plurality of sixth temperature sensors 106 correspond to the plurality of indoor units 13 and are provided at the return air outlets 134 of the corresponding indoor units 13 to detect the return air temperature value of the return air outlet 134. The controller 14 is coupled to a third temperature sensor 103, a fourth temperature sensor 104, a plurality of fifth temperature sensors 105, and a plurality of sixth temperature sensors 106 to obtain an exhaust air temperature value, an intake air temperature value, a blown air temperature value, and a return air temperature value.

[0060] S102, an abnormal indoor unit among the plurality of indoor units 13 is determined according to the characteristic data of each indoor unit among the plurality of indoor units 13.

[0061] The abnormal indoor unit mentioned above refers to an indoor unit 13 in an abnormal operating state, that is, an indoor unit 13 in which the corresponding electronic expansion valve 12 is a faulty electronic expansion valve. Similarly, if the electronic expansion valve 12 corresponding to the indoor unit 13 is not a faulty electronic expansion valve, the indoor unit 13 is understood to be in a normal operating state.

[0062] In addition, a failure of an electronic expansion valve in the multi-air conditioning system 10 causes a change in the characteristic data of the multiple indoor units 13. For example, when the multi-air conditioning system 10 operates normally, the temperature difference between the temperature value of the liquid pipe 16 connected to one of the indoor units and the temperature value of the gas pipe 15 connected to the indoor unit is smaller than a certain threshold. When a certain electronic expansion valve 12 fails to open normally, the amount of refrigerant in the indoor unit 13 corresponding to the electronic expansion valve 12 becomes insufficient, and the indoor unit 13 cannot evaporate or condense the refrigerant normally. As a result, the temperature difference between the temperature value of the liquid pipe 16 connected to the indoor unit 13 and the temperature value of the gas pipe 15 connected to the indoor unit 13 increases until it exceeds the certain threshold. Therefore, the controller 14 may determine whether the indoor unit is an abnormal indoor unit according to the characteristic data of any one of the indoor units.

[0063] Furthermore, because each component in the multi-air conditioning system 10 cooperates with each other to form a whole, if there is an abnormal indoor unit in the multi-air conditioning system 10, the operating data of the other components in the entire multi-air conditioning system 10 will also change. Therefore, any of the operating data such as the above exhaust pressure value, intake pressure value, exhaust temperature value, intake temperature value, indoor unit blowing temperature value, and indoor unit return air temperature value may be treated as characteristic data of the indoor unit.

[0064] In some embodiments, the controller 14 may obtain a fault identification result by inputting the characteristic data of each indoor unit among the plurality of indoor units into a fault identification model based on Deep Neural Networks (DNN). Deep Neural Networks (DNN) is a technology in the field of Machine Learning (ML). Since the fault identification model based on Deep Neural Networks (DNN) can output for multiple labels, the fault identification result can indicate whether each indoor unit among the plurality of indoor units 13 is an abnormal indoor unit. In this manner, the controller 14 may determine an abnormal indoor unit among the plurality of indoor units 13 according to the fault identification result.

[0065] In some embodiments, a fault identification model based on a deep neural network (DNN) is pre-stored in the memory of the controller 14. In some examples, the controller 14 or another device having processing capability may obtain a trained fault identification model based on a deep neural network (DNN) by training the fault identification model based on a deep neural network according to a historical feature data set when the multiple indoor units 13 are in a normal operating state and a historical feature data set when the multiple indoor units 13 are in an abnormal operating state, and store the trained fault identification model in the memory of the controller 14.

[0066] S103, the electronic expansion valve corresponding to the abnormal indoor unit is determined as a faulty electronic expansion valve.

[0067] In some embodiments, the controller 14 may determine one or more abnormal indoor units from the multiple indoor units 13, and thereby determine one or more electronic expansion valves 12 corresponding to the one or more abnormal indoor units as faulty electronic expansion valves.

[0068] The multi-air conditioning system 10 provided by the embodiment of the present disclosure can obtain characteristic data of the multiple indoor units 13 in the multi-air conditioning system 10 when a failure of an electronic expansion valve occurs in the multi-air conditioning system 10, and can determine an abnormal indoor unit among the multiple indoor units 13 according to the characteristic data of the multiple indoor units 13, and can determine the electronic expansion valve 12 corresponding to the abnormal indoor unit as the faulty electronic expansion valve. In this way, it is not necessary for a professional maintenance person to spend a lot of time observing and analyzing the faulty electronic expansion valve based on personal experience, and it is possible to accurately identify the faulty electronic expansion valve in the multi-air conditioning system 10, thereby improving the accuracy and degree of automation of locating the faulty electronic expansion valve in the multi-air conditioning system 10, and thus improving the efficiency of locating the fault in the multi-air conditioning system 10.

[0069] Hereinafter, mainly with reference to the drawings, an exemplary method for the controller 14 to detect whether or not a failure has occurred in the electronic expansion valve in the multi-air conditioning system 10 will be described. As shown in Fig. 10, the controller 14 may determine whether or not a failure has occurred in the electronic expansion valve in the multi-air conditioning system 10 by executing steps S201 to S203.

[0070] S201, operation data of the multi-air conditioning system 10 is obtained.

[0071] The above-mentioned operating data is parameter information generated during operation of the multi-air conditioning system 10. The operating data includes, for example, at least one of an operating current value of the compressor 111, an exhaust pressure value of the compressor 111, an exhaust temperature value of the compressor 111, an outlet temperature value of the outlets 133 of the multiple indoor units 13, and a return air temperature value of the return air outlets 134 of the multiple indoor units 13.

[0072] In some embodiments, after the controller 14 turns on the fault detection function as described above, the controller 14 may obtain operating data of the multi-air conditioning system 10.

[0073] It should be noted that the above examples of characteristic data and operational data in the embodiments of the present disclosure are illustrative, and the characteristic data and operational data may further include other data related to the operation of the multi-air conditioning system 10, which will not be repeated here.

[0074] S202, determining whether a failure occurs in the electronic expansion valve of the multi-air conditioning system 10 according to the operating data.

[0075] In some embodiments, the controller 14 may obtain a fault diagnosis result by inputting the operation data of the multi-air conditioning system 10 into a fault diagnosis model based on a support vector machine (SVM). The fault diagnosis result indicates whether a fault of the electronic expansion valve occurs in the multi-air conditioning system 10. In this way, the controller 14 may determine whether a fault of the electronic expansion valve occurs in the multi-air conditioning system 10 according to the fault diagnosis result. Illustratively, the support vector machine SVM is a broad linear classifier that performs binary classification on data according to a supervised learning method. Because the support vector machine SVM has excellent performance in binary classification, the fault diagnosis model based on the support vector machine SVM can improve the accuracy of determining whether a fault of the electronic expansion valve occurs in the multi-air conditioning system 10.

[0076] In some embodiments, a fault diagnosis model based on a support vector machine (SVM) is pre-stored in the memory of the controller 14. In some examples, the controller 14 or another device having processing capability may obtain a trained fault diagnosis model based on a support vector machine (SVM) by training the fault diagnosis model based on a support vector machine (SVM) according to a historical operation data set when no electronic expansion valve failure occurs in the multi-air conditioning system 10 and a historical operation data set when an electronic expansion valve failure occurs, and store the trained fault diagnosis model based on a support vector machine (SVM) in the memory of the controller 14.

[0077] In some embodiments, when the controller 14 determines that a failure of the electronic expansion valve has occurred in the multi-air conditioning system 10, the controller 14 executes steps S101 to S103 described above.

[0078] In some embodiments, if the controller 14 determines that no electronic expansion valve failure occurs in the multi-air conditioning system 10, the controller 14 executes the following step S203.

[0079] S203, sending a first prompt message.

[0080] The above first prompt message is used to indicate that the multi-air conditioning system 10 does not have an electronic expansion valve failure.

[0081] For example, if the indoor units 13 are equipped with displays, the first prompt message may be information such as characters, images, etc. displayed via the displays. Alternatively, if the indoor units 13 are equipped with speakers, the first prompt message may be audio information emitted via the speakers. Alternatively, if the multi-air conditioning system 10 is communicatively connected to a user's terminal device, the first prompt message may be information such as characters, images, audio, vibration, etc. transmitted via the terminal device. Note that the first prompt message may be information in other forms, such as lighting information, and the present disclosure is not limited thereto.

[0082] In some embodiments, after the controller 14 determines the faulty electronic expansion valve, i.e., after the above step S103, the controller 14 may send a second prompt message to indicate that the faulty electronic expansion valve is faulty. In some examples, as shown in FIG 11, the controller 14 sends the second prompt message by executing the following steps S301 to S303.

[0083] S301, after determining the faulty electronic expansion valve, obtain the opening degree of the faulty electronic expansion valve.

[0084] As described above, the controller 14 adjusts the opening of the electronic expansion valve 12 to adjust the amount of refrigerant input or output of the indoor unit 13 corresponding to the electronic expansion valve 12. Therefore, the abnormal operation state of an abnormal indoor unit is usually caused by an abnormal opening of the electronic expansion valve corresponding to the abnormal indoor unit. Furthermore, the opening of the electronic expansion valve can indicate the degree of failure of the electronic expansion valve.

[0085] S302, determining a failure level of the failed electronic expansion valve according to the opening degree of the failed electronic expansion valve.

[0086] In some embodiments, the controller 14 may determine the failure level of the faulty electronic expansion valve according to a first correspondence between the opening degree and the failure level of the faulty electronic expansion valve. The first correspondence may be pre-stored in the memory of the controller 14.

[0087] The normal opening degrees of the multiple electronic expansion valves 12 are related to the operating state of the multiple air conditioning system 10.

[0088] In some examples, when the multiple air conditioning system 10 is in a heating operation state, the normal opening degree of the multiple electronic expansion valves 12 should be 100% (i.e., the multiple electronic expansion valves 12 should be fully open). In the examples, the smaller the opening degree of the faulty electronic expansion valve, the higher the fault level of the faulty electronic expansion valve. Exemplarily, when the multiple air conditioning system 10 is in a heating operation state, a first correspondence relationship between the opening degree and the fault level of the faulty electronic expansion valve is shown in Table 1 below. [Table 1]

[0089] Referring to Table 1, when the opening degree of the faulty electronic expansion valve is within the range of 75% to 99%, the controller 14 may determine that the failure level of the faulty electronic expansion valve is level 1. When the opening degree of the faulty electronic expansion valve is within the range of 50% to 74%, the controller 14 may determine that the failure level of the faulty electronic expansion valve is level 2. When the opening degree of the faulty electronic expansion valve is within the range of 24% to 49%, the controller 14 may determine that the failure level of the faulty electronic expansion valve is level 3. When the opening degree of the faulty electronic expansion valve is 23% or less, the controller 14 may determine that the failure level of the faulty electronic expansion valve is level 4. Note that the failure levels of the faulty electronic expansion valve increase in order from "Level 1" to "Level 2", "Level 3", and "Level 4", and the urgency of the inspection and repair performed on the faulty electronic expansion valve also increases in order.

[0090] In some other examples, when the multi-air conditioning system 10 is in a cooling operation state, the normal opening degree of the multiple electronic expansion valves 12 should be 12% to 13%. In this example, when the opening degree of the faulty electronic expansion valve is greater than 13%, the greater the opening degree of the faulty electronic expansion valve, the higher the fault level of the faulty electronic expansion valve, and thus the greater the need to inspect and repair the faulty electronic expansion valve. Exemplarily, when the multi-air conditioning system 10 is in a cooling operation state, a first correspondence relationship between the opening degree and the fault level of the faulty electronic expansion valve is shown in Table 2 below. [Table 2]

[0091] Referring to Table 2, when the opening degree of the faulty electronic expansion valve is within the range of 75% to 100%, the controller 14 may determine that the failure level of the faulty electronic expansion valve is level 4. When the opening degree of the faulty electronic expansion valve is within the range of 50% to 74%, the controller 14 may determine that the failure level of the faulty electronic expansion valve is level 3. When the opening degree of the faulty electronic expansion valve is within the range of 25% to 49%, the controller 14 may determine that the failure level of the faulty electronic expansion valve is level 2. When the opening degree of the faulty electronic expansion valve is within the range of 14% to 24%, or is 12% or less, the controller 14 may determine that the failure level of the faulty electronic expansion valve is level 1.

[0092] S303, sending a second prompt message.

[0093] The second prompt message is used to indicate the fault level of the faulty electronic expansion valve.

[0094] In some embodiments, similar to the manner of transmitting the first prompt message in step S203 above, the controller 14 may transmit the second prompt message via a display, a speaker, a terminal device, etc. of the indoor unit 13 (e.g., an abnormal indoor unit). Taking the fault level of the faulty electronic expansion valve as level 4 and the number of the faulty electronic expansion valve as 001 as an example, as shown in FIG. 12, the second prompt message may be text information such as "The electronic expansion valve with the number 001 has a serious fault and it is suggested that you inspect and repair it immediately!"

[0095] In the above embodiment, after identifying the faulty electronic expansion valve in the multi-air conditioning system 10, the multi-air conditioning system 10 determines the fault level of the faulty electronic expansion valve according to a first correspondence relationship between the opening degree and fault level of the faulty electronic expansion valve, and sends a second prompt message corresponding to the fault level of the faulty electronic expansion valve, thereby prompting the user to reasonably arrange inspection and repair operation for the faulty electronic expansion valve according to the fault level of the faulty electronic expansion valve, and can avoid the reduction in the cooling and heating effect or heating effect of the multi-air conditioning system 10 caused by the failure of the electronic expansion valve.

[0096] In some embodiments of the present disclosure, a fault location method for a multi-air conditioning system is further provided. The multi-air conditioning system may be, for example, the above-mentioned multi-air conditioning system 10. The method may include, for example, each step performed by the above-mentioned controller 14. The beneficial effects of the method include at least the beneficial effects of the above-mentioned multi-air conditioning system 10, which will not be repeated here.

[0097] Since the operation data of different models of multi-air conditioning systems are different, in the related art, it is necessary to collect operation data of each model of multi-air conditioning system in a normal operation state and operation data of each model of multi-air conditioning system in an abnormal operation state (operation state in which a fault occurs) as a sample set and establish a fault diagnosis model. In this way, the fault diagnosis model can be applied to multiple types of multi-air conditioning systems, thereby improving the adaptability and accuracy of fault diagnosis for the multi-air conditioning system using the fault diagnosis model. However, since it is necessary to collect operation data of multiple models of multi-air conditioning systems, this method of training the fault diagnosis model makes the establishment period of the fault diagnosis model too long, and thus the efficiency of fault diagnosis for the multi-air conditioning system using the fault diagnosis model is low.

[0098] Based on the above technical problems, some embodiments of the present disclosure further provide a fault diagnosis model training method for a multi-air conditioning system. The method may be used to establish a fault diagnosis model for a second multi-air conditioning system by constructing a first feature offset space of the first multi-air conditioning system according to the value of the operation data in the normal operation state of the first multi-air conditioning system (i.e., the normal value of the operation data) and the value of the operation data when various faults occur (i.e., the fault value of the operation data), and correcting the first feature offset space according to the difference between the normal value of the operation data of the first multi-air conditioning and the normal value of the operation data of the second multi-air conditioning to obtain a second feature offset space of the second multi-air conditioning, thereby obtaining the fault value of the operation data of the second multi-air conditioning system according to the second feature offset space and the normal value of the operation data of the second multi-air conditioning system. In this way, in the process of establishing a fault diagnosis model for the second multi-air conditioning system, there is no need to collect operating data for various fault operating states of the second multi-air conditioning system under actual operating conditions, thereby shortening the establishment period of the fault diagnosis model and ultimately improving the efficiency of fault diagnosis for the multi-air conditioning system using the fault diagnosis model.

[0099] As shown in Fig. 13, the above-mentioned fault diagnosis model training method for a multi-air conditioning system includes the following steps S401 to S405. The method may be executed by the above-mentioned controller 14, or may be executed by a device having other processing capabilities such as a server. In the following embodiment, the method is exemplarily described by taking the controller 14 as an example for executing the method. Also, the structure and operation principle of the multi-air conditioning system can be referred to the multi-air conditioning system 10 in the above-mentioned embodiment, and will not be repeated here.

[0100] S401, obtaining normal values ​​and fault values ​​of multiple operating data of a first multi-air conditioning system;

[0101] In some embodiments, the first multi air conditioning system may be referred to as an experimental multi air conditioning system. A memory of the first multi air conditioning system stores historical operating data generated when the first multi air conditioning system operates under various operating conditions.

[0102] The above operating data includes, for example, the intake temperature value of the compressor 111, the exhaust temperature value of the compressor 111, the intake pressure value of the compressor 111, the exhaust pressure value of the compressor 111, the opening degree of multiple electronic expansion valves 12, the operating current value of the compressor 111, the ambient temperature value where the outdoor unit 11 is located, the average ambient temperature value where the multiple indoor units are located, the intake superheat degree of the compressor 111, the exhaust superheat degree of the compressor 111, the operating temperature value of the outdoor unit 11, and the operating temperature values ​​of the multiple indoor units 13.

[0103] For example, the intake superheat degree refers to the difference between the intake temperature value of the compressor 111 and the saturation temperature at the intake pressure value of the refrigerant. The exhaust superheat degree refers to the difference between the exhaust temperature value of the compressor 111 and the saturation temperature at the exhaust intake pressure value of the refrigerant. The operating temperature value of the outdoor unit 11 may be, for example, the operating temperature value of the outdoor heat exchanger 112. The operating temperature value of an indoor unit 13 among the multiple indoor units 13 may be, for example, the operating temperature value of the indoor heat exchanger 131 of the indoor unit 13.

[0104] In some examples, as shown in FIG. 14, the above step S101 may be specifically realized by the following steps S4011 and S4012.

[0105] S4011, historical operation data of the first multi-air conditioning system is obtained.

[0106] Here, the historical operation data includes normal operation data generated when the first multi-air conditioning system is in normal operation during a historical period, and various fault operation data generated when various faults occur in the first multi-air conditioning system. Note that the present disclosure does not limit the length of the historical period.

[0107] S4012, the historical operating data is analyzed, and normal values ​​of the multiple operating data of the first multi-air conditioning system when the first multi-air conditioning system is in a normal operating state and fault values ​​when a fault occurs in the first multi-air conditioning system are determined.

[0108] In addition, since the normal value of any of the multiple operating data is different from the fault value of the operating data, the controller 14 analyzes the historical operating data of the multi-air conditioning system, distinguishes between the multiple operating data generated when the multi-air conditioning system is in a normal operating state and the multiple operating data generated when a fault occurs in the multi-air conditioning system, and can obtain the normal value and fault value of each operating data in the multiple operating data. For example, faults that may occur in the multiple multi-air conditioning systems include refrigerant leakage, excess refrigerant involved in circulation, or abnormal opening of the electronic expansion valve 12, etc.

[0109] For example, the controller 14 may analyze the historical operating data according to set value ranges corresponding to the plurality of operating data. If the value of any of the plurality of operating data is within the corresponding set value range, the value of the operating data is determined to be a normal value. If the value of any of the operating data is outside the corresponding set value range, the value of the operating data is determined to be a fault value. Here, the set value range may be preset by, for example, an employee or a manufacturer.

[0110] In addition, when different faults occur in the multi-air conditioning system, the fault values ​​of the multiple operation data are usually different. When analyzing the historical operation data of the first multi-air conditioning system, the controller 14 may associate the fault value of the first multi-air conditioning system with the fault that occurred in the first multi-air conditioning system.

[0111] S402, determining a first feature offset space of the first multi-air conditioning system according to normal values ​​and fault values ​​of a plurality of operating data of the first multi-air conditioning system.

[0112] In addition, since there is a deviation between the normal values ​​and fault values ​​of the multiple operating data, a first feature offset space of the first multi-air conditioning system may be constructed according to the offset between the fault values ​​and normal values ​​of the multiple operating data. The first feature offset space includes the offset of each operating data of the multiple operating data of the first multi-air conditioning system.

[0113] In some embodiments, the space consisting of normal values ​​of multiple operating data of the multiple air conditioning systems may be referred to as a feature space of the multiple air conditioning systems.

[0114] Exemplarily, the first feature space of the first multi-air conditioning system may be expressed, for example, as the following matrix 1:

[0115] [Matrix 1] X=[x1x2... x n-1 x n ]

[0116] where x j is a column vector of driving data, where j ranges from 1 to n, and n is an integer greater than 1.

[0117] Illustratively, in a certain fault, the first feature offset space of the first multi-air conditioning system may be expressed as the following matrix 2:

[0118] [Matrix 2] Δxi = [Δxi1Δxi2... Δxi n-1 Δxi n ]

[0119] Here, Δxi j is the offset of some operational data, and the value of j ranges from 1 to n, where n is an integer greater than 1.

[0120] S403, correcting the first feature offset space based on a difference between the normal values ​​of the multiple operating data of the first multi-air conditioning system and the normal values ​​of the multiple operating data of the second multi-air conditioning system, to obtain a second feature offset space of the second multi-air conditioning system.

[0121] In addition, when there is a difference between the normal values ​​of the plurality of operating data of the first multi air conditioning system and the normal values ​​of the plurality of operating data of the second multi air conditioning system, it is considered that there is a difference between the model of the first multi air conditioning system and the model of the second multi air conditioning system. For example, the model of the first multi air conditioning system is a cooling-only type, and the model of the second multi air conditioning system is a heat pump type.

[0122] In addition, since the thermophysical mechanisms that cause the failures of various multi-air conditioning systems are similar, different models of multi-air conditioning systems usually have similar feature offset spaces, so the second feature offset space of the second multi-air conditioning system may be obtained by correcting the first feature offset space based on the difference between the model of the first multi-air conditioning system and the model of the second multi-air conditioning system.

[0123] Exemplarily, a second correspondence relationship between the model of the multi-air conditioning system and the correction coefficient is pre-stored in the memory of the controller 14. The correction coefficient is, for example, a ratio between the feature offset space of the other multi-air conditioning system and the first feature offset space of the first multi-air conditioning system. After determining the difference between the normal values ​​of the multiple operating data of the first multi-air conditioning system and the normal values ​​of the multiple operating data of the second multi-air conditioning system, the controller 14 determines the model of the second multi-air conditioning system according to the model of the first multi-air conditioning system, thereby determining a correction coefficient for the first feature offset space of the second feature offset space according to the model of the second multi-air conditioning system and the second correspondence, and thus correcting the first feature offset space according to the correction coefficient to obtain the second feature offset space. For example, the controller 14 obtains the second feature offset space by multiplying the correction coefficient by the first feature offset space.

[0124] Exemplarily, the above second correspondence relationship may be obtained through an experiment or a simulation.

[0125] S404, determining fault values ​​of the plurality of operating data of the second multi-air conditioning system according to the normal values ​​and the second feature offset space of the plurality of operating data of the second multi-air conditioning system.

[0126] In some embodiments, the controller 14 may analyze historical operating data of the second multi-air conditioning system under normal operating conditions during a historical period, determine normal values ​​of the multiple operating data of the second multi-air conditioning system, and thereby obtain fault values ​​of the multiple operating data of the second multi-air conditioning system according to the normal values ​​of the multiple operating data of the second multi-air conditioning system and the second feature offset space.

[0127] Illustratively, the controller 14 may obtain fault values ​​of the plurality of operating data of the second multi-air conditioning system by summing the normal values ​​of the plurality of operating data of the second multi-air conditioning system and the second feature offset space.

[0128] S405, training a fault diagnosis model according to normal values ​​and fault values ​​of the multiple operation data of the second multi-air conditioning system.

[0129] In some embodiments, the controller 14 may train a fault diagnosis model using normal and fault values ​​of multiple operating data of the second multi-air conditioning system as a sample set.

[0130] In some examples, the above fault diagnosis model is a fault diagnosis model based on a one-dimensional convolutional neural network (CNN). Here, the convolutional neural network is a multi-layer perceptron. The working principle of the convolutional neural network is mainly related to three basic concepts: local receptive field, pooling, and shared weights. The one-dimensional convolutional neural network is a convolutional neural network with one-dimensional input data and has classification ability, so the one-dimensional convolutional neural network can be used for fault detection and diagnosis of a multi-air conditioning system. Fault detection is the process of detecting whether a fault occurs in the system. Fault diagnosis is to obtain detailed information such as the fault type and fault severity of the fault.

[0131] In some embodiments, as shown in FIG. 15, the fault diagnosis model may include an input layer, a convolution layer, a pooling layer, a fully connected layer, and an output layer.

[0132] A convolutional layer is an important structure in a convolutional neural network. The function of a convolutional layer is to form and output a set of feature maps of the original input data by convolving the input data from the input layer with a set of filters. When a filter convolves the input data of the convolutional layer, a local receptive field moves repeatedly on the input data. The data in the local receptive field is dot-producted with the weight matrix in the filter and a fixed offset value is added to form an output matrix. The output matrix is ​​a feature map of the original input data. The filters have a shared weight feature for the input convolution operation. That is, the weight matrix and offset used by a filter for the data in the local receptive field are the same.

[0133] Exemplarily, an activation function (e.g., a ReLU activation function) is applied to the output of the convolution layer to perform nonlinearity, thereby improving the nonlinear fitting ability of the convolution layer. For example, the ReLU activation function may be expressed as the following formula (1):

[0134] [Formula (1)] JPEG2025510812000004.jpg1755

[0135] Output of the i-th convolutional layer a i may be expressed as the following equation (2):

[0136] [Formula (2)] JPEG2025510812000005.jpg1076

[0137] Where: JPEG2025510812000006.jpg88 is the convolution operation, σ is the ReLU activation function, and b i is the offset value, and w i is the weight matrix.

[0138] The output of the convolutional layer may be fed to a pooling layer, which splits the input data into multiple pooling regions and aggregates each pooling region to form an output. The output of the pooling layer is a generalized and simplified feature map of its input.

[0139] The fully connected layer plays the role of a "classifier" in the whole convolutional neural network and can map the distributed features into the sample labeling space, that is, the fully connected layer is used to integrate the output of the pooling layer to obtain the output of the fully connected layer, and input the output of the fully connected layer into the output layer.

[0140] For example, a classification network (softmax) layer may be used as the output layer of the convolutional neural network. In this way, the classification result of the input data of the softmax layer can be determined according to the dimension in which the maximum value of the probability vector at the output of the softmax layer is located.

[0141] The fault diagnosis model training method for a multi-air conditioning system provided by the embodiment of the present disclosure obtains a first feature offset space used to characterize the offset between the normal values ​​and the fault values ​​of the multiple operating data of the first multi-air conditioning system according to the normal values ​​and fault values ​​of the multiple operating data of the first multi-air conditioning system, and obtains a second feature offset space of the second multi-air conditioning system by correcting the first feature offset space according to the difference between the model of the second multi-air conditioning system and the model of the first multi-air conditioning system. Thus, the fault values ​​of the multiple operating data of the second multi-air conditioning system are obtained according to the second feature offset space and the normal values ​​of the multiple operating data of the second multi-air conditioning system. Furthermore, the fault diagnosis model is trained using the fault values ​​and normal values ​​of the multiple operating data of the second multi-air conditioning system, thereby obtaining a fault diagnosis model applied to the second multi-air conditioning system after training. In this way, a fault diagnosis model for the second multi-air conditioning system can be established without the need to collect multiple operating data fault values ​​when various faults occur in the second multi-air conditioning system under actual operating conditions, thereby shortening the establishment period of the fault diagnosis model and ultimately improving the efficiency of fault diagnosis for the second multi-air conditioning system using the fault diagnosis model.

[0142] In some embodiments, as shown in FIG. 16, the above step S405 may be specifically realized by the following steps S501 and S502.

[0143] S501, determining at least one first operating data from the plurality of operating data of the second multi-air conditioning system according to normal values ​​and fault values ​​of the plurality of operating data of the second multi-air conditioning system;

[0144] In addition, the multiple operating data of the second multi-air conditioning system may be doped with some redundant operating data that is not related to the training of the fault diagnosis model, so that data filtering is required for the multiple operating data in order to improve the training speed of the fault diagnosis model. For example, the at least one first operating data is operating data shared by different types of multi-air conditioning systems and has high relevance to the training of the fault diagnosis model.

[0145] For example, the controller 14 may calculate the difference between the normal value and the fault value of each of the plurality of operating data of the second multi-air conditioning system, and select the operating data corresponding to a difference among the plurality of differences that is greater than a set threshold value as the alternative operating data, and may extract the operating data shared by at least one of the various types of multi-air conditioning systems from the alternative operating data as the first operating data. Here, the set threshold value may be preset by an employee or a manufacturer.

[0146] Furthermore, the greater the difference between the normal value and the fault value of certain operating data, the more likely it is that the operating data can reflect the occurrence of a fault in the second multi-air conditioning system. Therefore, using the operating data as the first operating data for training the fault detection model is advantageous for improving the accuracy of fault detection by the trained fault detection model.

[0147] S502, training a fault diagnosis model according to normal values ​​and fault values ​​of at least one first operating data of the second multi-air conditioning system.

[0148] The method for training a fault diagnosis model of a multi-air conditioning system in the above embodiment extracts at least one first operation data from the multiple operation data of the second multi-air conditioning system by data filtering the multiple operation data of the second multi-air conditioning system, and then trains a fault diagnosis model using the normal value and fault value of the at least one first operation data. The training sample set of the fault diagnosis model is simplified, so that the training speed of the fault diagnosis model can be improved, and the efficiency of fault diagnosis for the multi-air conditioning system using the fault diagnosis model is improved.

[0149] In some embodiments, as shown in FIG. 17, step S502 may be specifically realized by the following steps S601 to S603.

[0150] S601, training an autoencoder model based on normal values ​​and fault values ​​of at least one first operating data of a second multi-air conditioning system.

[0151] An autoencoder model is an unsupervised learning model. Exemplarily, as shown in FIG. 18, an autoencoder includes an encoder and a decoder. The encoder is configured to encode high-dimensional input data (i.e., original feature data) into low-dimensional latent variables (i.e., compressed data), so that the autoencoder model learns data with higher information content. The decoder is configured to restore the low-dimensional latent variables to the original dimensions of the high-dimensional input data. The process in which the original feature data is encoded by the encoder and decoded by the decoder is a data reconstruction process of the original feature data. Exemplarily, the process of training an autoencoder model may include the following steps 1 to 4.

[0152] Step 1: The controller 14 converts normal and fault values ​​of at least one first operational data into a feature vector matrix X={X1, X2, ..., X n} and input the feature vector matrix into the autoencoder model.

[0153] where X1,X2,…,X n represents a normal value and a fault value of the at least one first operational data.

[0154] Step 2: The encoder compresses the original feature data into the hidden layer using the method shown in equation (3) below.

[0155] [Formula (3)] JPEG2025510812000007.jpg1272

[0156] Here, σ e is a Sigmoid function, X is the original feature dataset, and W e are the encoder weight parameters, and B e is the encoder deviation, and H is the mapping of the original feature data in the hidden layer.

[0157] Step 3: The decoder reconstructs the original feature data according to the method shown in the following equation (4), and outputs the reconstructed feature data.

[0158] [Formula (4)] JPEG2025510812000008.jpg1156

[0159] Here, σ d is a sigmoid function, and W d is the weight parameter of the decoder, and B d is the deviation of the decoder, JPEG2025510812000009.jpg107 is the original feature data after reconstruction.

[0160] Step 4: Train an autoencoder model to reduce the reconstruction error and obtain the corresponding W e , W d , and I get JPEG2025510812000010.jpg107.

[0161] Exemplarily, the calculation formula for the reconstruction error is as shown in the following formula (5).

[0162] [Formula (5)] JPEG2025510812000011.jpg14126

[0163] Where: JPEG2025510812000012.jpg920 is the softmax reconstruction error, X i is the original feature data, JPEG2025510812000013.jpg129 is the reconstructed feature data.

[0164] S602, inputting the normal values ​​and fault values ​​of at least one first operating data of the second multi-air conditioning system into the trained autoencoder model to obtain data reconstructed normal values ​​and data reconstructed fault values ​​of the at least one first operating data of the second multi-air conditioning system.

[0165] S603, training a fault diagnosis model based on the data reconstructed normal value and the data reconstructed fault value.

[0166] The fault diagnosis model training method for a multi-air conditioning system in the above embodiment uses an autoencoder to reconstruct normal values ​​and fault values ​​of at least one first operating data of a second multi-air conditioning system, thereby reducing data noise (i.e., random errors in the data due to measurement or other reasons) of the normal values ​​and fault values ​​of the at least one first operating data, thereby removing misleading data from the normal values ​​and fault values ​​of the at least one first operating data that is useful for training a fault detection model, and thereby improving the accuracy of fault detection using the fault detection model.

[0167] It will be appreciated by those skilled in the art that the scope of the disclosure of the present invention is not limited to the specific embodiments described above, and that modifications and substitutions may be made to the specific elements of the embodiments without departing from the spirit of the present application. The scope of the disclosure is limited by the claims.

Claims

1. A multi-air conditioning system, The outdoor unit, a plurality of indoor units, each of which is connected to a corresponding gas pipe and a corresponding liquid pipe, and thereby communicates with the outdoor unit via the gas pipe and the liquid pipe; a plurality of electronic expansion valves corresponding to the plurality of indoor units, the plurality of electronic expansion valves being provided in the liquid pipes to which the corresponding indoor units are connected, and configured to control a refrigerant output amount or a refrigerant input amount of the corresponding indoor units; A controller; Equipped with The controller: When a failure occurs in an electronic expansion valve in the multi-air conditioning system, characteristic data of each indoor unit among the plurality of indoor units is acquired, and the characteristic data of each indoor unit includes a temperature difference between a temperature value of the liquid pipe connected corresponding to the indoor unit and a temperature value of the gas pipe connected corresponding to the indoor unit; determining an abnormal indoor unit among the plurality of indoor units according to the characteristic data of each indoor unit among the plurality of indoor units; and determining that the electronic expansion valve corresponding to the abnormal indoor unit is a faulty electronic expansion valve. Multi-air conditioning system.

2. The controller: The characteristic data of each indoor unit among the plurality of indoor units is input to a fault identification model based on a deep neural network DNN, and the abnormal indoor unit among the plurality of indoor units is determined according to a fault identification result of the fault identification model, The outdoor unit includes a compressor, Each of the indoor units includes an air outlet and a return air outlet, The characteristic data of each indoor unit further includes at least one of an exhaust pressure value of the compressor, an intake pressure value of the compressor, an exhaust temperature value of the compressor, an intake temperature value of the compressor, an outlet temperature value of the air outlet of the indoor unit, and a return air temperature value of the return air outlet of the indoor unit. The multi-air conditioning system according to claim 1 .

3. The outdoor unit includes a compressor, Each of the indoor units includes an air outlet and a return air outlet, The controller further comprises: Acquire operating data of the multi-air conditioning system, the operating data including at least one of an operating current value of the compressor, an exhaust pressure value of the compressor, an exhaust temperature value of the compressor, an outlet temperature value of the outlets of the plurality of indoor units, and a return air temperature value of the return air ports of the plurality of indoor units; and determining whether a failure has occurred in the electronic expansion valve of the multi-air conditioning system according to the operating data. A multi-air conditioning system according to claim 1 or 2.

4. The controller: The method is configured to input the operating data into a fault diagnosis model based on a support vector machine (SVM), and determine whether a fault has occurred in the electronic expansion valve of the multi-air conditioning system according to a fault diagnosis result of the fault diagnosis model. The multi-air conditioning system according to claim 3.

5. The controller further comprises: When a failure of the electronic expansion valve does not occur in the multi-air conditioning system, a first prompt message is sent, and the first prompt message is used to indicate that a failure of the electronic expansion valve does not occur in the multi-air conditioning system. A multi-air conditioning system according to any one of claims 1 to 4.

6. The controller further comprises: After determining the faulty electronic expansion valve, obtain the opening degree of the faulty electronic expansion valve; determining a failure level of the failed electronic expansion valve according to an opening degree of the failed electronic expansion valve; and transmitting a second prompt message, the second prompt message being used to indicate the fault level of the faulty electronic expansion valve. A multi-air conditioning system according to any one of claims 1 to 5.

7. A method for identifying a fault location in a multi-air conditioning system, comprising: The multi-air conditioning system includes: The outdoor unit, a plurality of indoor units, each of which is connected to a corresponding gas pipe and a corresponding liquid pipe, and thereby communicates with the outdoor unit via the gas pipe and the liquid pipe; a plurality of electronic expansion valves corresponding to the plurality of indoor units, the plurality of electronic expansion valves being provided in the liquid pipes to which the corresponding indoor units are connected, and configured to control a refrigerant output amount or a refrigerant input amount of the corresponding indoor units; Equipped with The method comprises: a step of acquiring characteristic data of each indoor unit among the plurality of indoor units when a failure occurs in an electronic expansion valve of the multi-air conditioning system, the characteristic data of each indoor unit including a temperature difference between a temperature value of the liquid pipe connected corresponding to the indoor unit and a temperature value of the gas pipe connected corresponding to the indoor unit; determining an abnormal indoor unit among the plurality of indoor units according to the characteristic data of each indoor unit among the plurality of indoor units; determining that the electronic expansion valve corresponding to the abnormal indoor unit is a faulty electronic expansion valve; Including, A method for fault location in a multi-air conditioning system.

8. The step of determining the abnormal indoor unit among the plurality of indoor units according to the characteristic data of each indoor unit among the plurality of indoor units includes: inputting the characteristic data of each indoor unit among the plurality of indoor units into a fault identification model based on a deep neural network DNN, and determining the abnormal indoor unit among the plurality of indoor units according to a fault identification result of the fault identification model; The outdoor unit includes a compressor, Each of the indoor units includes an air outlet and a return air outlet, The characteristic data of each indoor unit further includes at least one of an exhaust pressure value of the compressor, an intake pressure value of the compressor, an exhaust temperature value of the compressor, an intake temperature value of the compressor, an outlet temperature value of the air outlet of the indoor unit, and a return air temperature value of the return air outlet of the indoor unit. The method of claim 7.

9. The outdoor unit includes a compressor, Each of the indoor units includes an air outlet and a return air outlet, The method further comprises: A step of acquiring operation data of the multi-air conditioning system, the operation data including at least one of an operating current value of the compressor, an exhaust pressure value of the compressor, an exhaust temperature value of the compressor, an outlet temperature value of the outlet of the plurality of indoor units, and a return air temperature value of the return air port of the plurality of indoor units; determining whether a failure occurs in the electronic expansion valve of the multi-air conditioning system according to the operating data; Including, The method according to claim 7 or claim 8.

10. The step of determining whether a failure has occurred in the electronic expansion valve of the multi-air conditioning system according to the operating data includes: inputting the operation data into a fault diagnosis model based on a support vector machine (SVM); and determining whether a fault occurs in the electronic expansion valve of the multi-air conditioning system according to a fault diagnosis result of the fault diagnosis model; 10. The method of claim 9.

11. The method further comprises: a step of transmitting a first prompt message when a failure of the electronic expansion valve does not occur in the multi-air conditioning system, the first prompt message being used to indicate that a failure of the electronic expansion valve does not occur in the multi-air conditioning system; A method according to any one of claims 7 to 10.

12. The method further comprises: After determining the faulty electronic expansion valve, acquiring the opening degree of the faulty electronic expansion valve; determining a failure level of the failed electronic expansion valve according to an opening degree of the failed electronic expansion valve; sending a second prompt message, the second prompt message being used to indicate the fault level of the faulty electronic expansion valve; Including, A method according to any one of claims 7 to 11.

13. A method for training a fault diagnosis model for a multi-air conditioning system, comprising: Obtaining normal values ​​and fault values ​​of a plurality of operating data of the first multi-air conditioning system; determining a first feature offset space of the first multi-air conditioning system based on normal values ​​and fault values ​​of the plurality of operation data of the first multi-air conditioning system, the plurality of operation data being parameter information generated during operation of the multi-air conditioning system, and the first feature offset space including a difference between a fault value and a normal value of each operation data among the plurality of operation data of the first multi-air conditioning system; Correcting the first feature offset space based on a difference between the normal values ​​of the plurality of operating data of the first multi-air conditioning system and the normal values ​​of the plurality of operating data of the second multi-air conditioning system to obtain a second feature offset space of the second multi-air conditioning system; determining a fault value of the plurality of operating data of the second multi-air conditioning system according to the normal value of the plurality of operating data of the second multi-air conditioning system and the second feature offset space; Training a fault diagnosis model according to normal values ​​and fault values ​​of the plurality of operating data of the second multi-air conditioning system; Including, A fault diagnosis model training method for multi-air conditioning system.

14. The step of training the fault diagnosis model based on normal values ​​and fault values ​​of the plurality of operating data of the second multi-air conditioning system includes: determining at least one first operating data from the plurality of operating data of the second multi-air conditioning system according to normal values ​​and fault values ​​of the plurality of operating data of the second multi-air conditioning system; Training the fault diagnosis model according to normal values ​​and fault values ​​of the at least one first operation data of the second multi-air conditioning system; Including, The method of claim 13.

15. training the fault diagnosis model according to normal values ​​and fault values ​​of the first operation data of the second multi-air conditioning system, Training an autoencoder model based on normal values ​​and fault values ​​of the at least one first operating data of the second multi-air conditioning system; Inputting the normal value and the fault value of the at least one first operation data of the second multi-air conditioning system into a trained autoencoder model to obtain a data reconstructed normal value and a data reconstructed fault value of the at least one first operation data of the second multi-air conditioning system; training the fault diagnosis model based on the data reconstructed normal values ​​and the data reconstructed fault values; Including, The method of claim 14.

16. The multi-air conditioning system includes: an outdoor unit including a compressor configured to compress a refrigerant to circulate the refrigerant within the multi-air conditioning system; A plurality of indoor units communicating with the outdoor unit; A plurality of electronic expansion valves corresponding to the plurality of indoor units and configured to control a refrigerant output amount or a refrigerant input amount of the corresponding indoor units; Equipped with The plurality of operating data include an intake temperature value of the compressor, an exhaust temperature value of the compressor, an intake pressure value of the compressor, an exhaust pressure value of the compressor, openings of the plurality of electronic expansion valves, an operating current value of the compressor, an environmental temperature value where the outdoor unit is located, an average value of environmental temperature values ​​where the plurality of indoor units are located, an intake superheat degree of the compressor, an exhaust superheat degree of the compressor, an operating temperature value of the outdoor unit, and an operating temperature value of the plurality of indoor units. A method according to any one of claims 13 to 15.

17. The step of acquiring normal values ​​and fault values ​​of the plurality of operating data of the first multi-air conditioning system includes: Obtaining historical operating data of the first multi-air conditioning system; Analyzing the historical operation data, and determining normal values ​​of the plurality of operation data of the first multi-air conditioning system in a normal operation state of the first multi-air conditioning system and fault values ​​of the plurality of operation data of the first multi-air conditioning system in the event of a fault of the first multi-air conditioning system; Including, A method according to any one of claims 13 to 16.

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