CN116697538A - Multi-split air conditioning system and control method thereof - Google Patents

Abstract

The invention provides a multi-split air conditioning system and a control method thereof, and relates to the technical field of air conditioners. The system comprises: an outdoor unit; the indoor unit comprises a plurality of indoor units connected in parallel; the outdoor unit includes a controller configured to: receiving mode request signals sent by a plurality of indoor units simultaneously, and judging whether mode conflict exists according to mutual exclusion relation among working modes corresponding to the mode request signals; under the condition of mode conflict, determining an optimal working mode under the current working condition according to the environmental parameters; and sending an optimal working mode starting feedback signal to the first type indoor unit, and sending an air supply mode starting feedback signal and a mode conflict reminding to the second type indoor unit. According to the invention, the optimal working mode is determined according to the environmental parameters, so that mode conflict is avoided, the working efficiency of the system and the use experience of a user are improved, and the energy-saving effect of the system is improved.

Description

Multi-split air conditioning system and control method thereof

Technical Field

The invention relates to the technical field of air conditioners, in particular to a multi-split air conditioning system and a control method thereof.

Background

The multi-split air conditioning system is an air conditioning system capable of simultaneously connecting a plurality of indoor units to one outdoor unit. The indoor units may be installed in different rooms or areas, and each indoor unit may individually control temperature and wind speed. The mode conflict of the multi-split air conditioning system refers to the conflict among different modes which possibly occurs when a plurality of indoor units work simultaneously, so that the system cannot normally operate or abnormal conditions occur.

In the related art, a multi-split air conditioning system judges priority according to the sequence of entering the modes. The priority of the mode which is entered first is higher, which leads to the failure of the operation of the indoor unit which possibly enters the mode later, so that the user experience is poor.

Disclosure of Invention

The embodiment of the application provides a multi-split air conditioning system and a control method thereof, and aims to solve the problem that the operation of an indoor unit in a later-entering mode fails and the experience of a user is poor due to higher priority of the mode which is firstly entered in the existing multi-split air conditioning system.

In order to solve the technical problems, the application is realized as follows:

in a first aspect, an embodiment of the present application provides a multi-split air conditioning system, including:

An outdoor unit;

the indoor unit comprises a plurality of indoor units connected in parallel;

the outdoor unit includes a controller configured to:

receiving mode request signals sent by a plurality of indoor units simultaneously, and judging whether mode conflict exists according to mutual exclusion relation among working modes corresponding to the mode request signals;

under the condition of mode conflict, determining an optimal working mode under the current working condition according to the environmental parameters;

and sending an optimal working mode starting feedback signal to the first type indoor unit, and sending an air supply mode starting feedback signal and a mode conflict reminding to the second type indoor unit.

The technical scheme provided by the embodiment of the application at least has the following beneficial effects: firstly, mode request signals transmitted by a plurality of indoor units simultaneously are received, whether mode conflict exists or not is judged, and if so, an optimal working mode is determined according to environmental parameters, so that the mode conflict is avoided, and the working efficiency of the system and the use experience of users are improved. And secondly, the system determines the optimal working mode under the current working condition according to the environmental parameters, and can select the optimal working mode under different environmental conditions, so that the energy-saving effect of the system is improved. Meanwhile, the system can automatically select the working mode according to the environmental parameters, and a user does not need to manually adjust, so that the use convenience of the user is improved. And finally, sending conflict reminding to the indoor units with the mode conflict, helping users to know the conflict among the indoor units in time, and taking measures to solve the problem, so that the indoor environment is better managed.

In some embodiments, the controller is further configured to:

the indoor unit matched with the working mode corresponding to the mode request signal and the optimal working mode is determined to be a first type indoor unit;

and determining the unmatched indoor units of the working mode corresponding to the mode request signal and the optimal working mode as the second type indoor units.

In some embodiments, the controller is further configured to:

determining the type of the mode conflict, wherein the type of the mode conflict comprises a refrigeration mode conflict and a heating mode conflict, and a dehumidification mode conflict and a heating mode conflict;

under the condition that the mode conflict type is that a refrigeration mode and a heating mode conflict, determining an optimal working mode under the current working condition according to the outdoor temperature and the indoor return air temperature;

and under the condition that the mode conflict type is that the dehumidification mode and the heating mode conflict, determining the optimal working mode under the current working condition according to the outdoor temperature, the indoor humidity and the indoor return air temperature.

In some embodiments, the system further comprises a first temperature sensor and at least one second temperature sensor;

a controller, further configured to:

acquiring outdoor temperature through a first temperature sensor, and acquiring indoor return air temperature of each indoor unit through at least one second temperature sensor;

Under the condition that the outdoor temperature is greater than or equal to a preset upper temperature threshold, determining that the optimal working mode under the current working condition is a refrigeration mode;

under the condition that the outdoor temperature is less than or equal to a preset temperature lower limit threshold value, determining an optimal working mode under the current working condition as a heating mode;

and under the condition that the outdoor temperature is in the temperature upper limit threshold value and the temperature lower limit threshold value, determining the optimal working mode under the current working condition according to the indoor return air temperature.

In some embodiments, the system further comprises at least one humidity sensor;

a controller, further configured to:

acquiring indoor humidity of each indoor unit through at least one humidity sensor;

under the condition that the indoor humidity is greater than or equal to a preset humidity threshold value, determining an optimal working mode under the current working condition as a dehumidification mode;

under the condition that the indoor humidity is smaller than a preset humidity threshold value and the outdoor temperature is larger than or equal to a preset temperature upper limit threshold value, determining that the optimal working mode under the current working condition is a dehumidification mode;

under the condition that the indoor humidity is smaller than a preset humidity threshold value and the outdoor temperature is smaller than or equal to a preset temperature lower limit threshold value, determining that the optimal working mode under the current working condition is a heating mode;

And under the condition that the indoor humidity is smaller than a preset humidity threshold value and the outdoor temperature is in a temperature upper limit threshold value and temperature lower limit threshold value interval, determining an optimal working mode under the current working condition according to the indoor return air temperature.

In some embodiments, the controller is further configured to:

the indoor unit with the indoor return air temperature being greater than or equal to a preset temperature upper limit threshold value is determined to be a third type indoor unit;

the indoor unit with the indoor return air temperature smaller than or equal to a preset temperature upper limit threshold value is determined to be a fourth type indoor unit;

determining a difference value calculation result of an indoor return air temperature average value of the third type indoor unit and a preset temperature upper limit threshold value as a first calculation result, and determining a difference value calculation result of an indoor return air temperature average value of the fourth type indoor unit and a preset temperature lower limit threshold value as a second calculation result;

and under the condition that the first calculation result is smaller than the second calculation result, determining the optimal working mode under the current working condition as a heating mode.

In some embodiments, the controller is further configured to:

Acquiring the number of the third type indoor units and the number of the fourth type indoor units under the condition that the first calculation result is equal to the second calculation result;

under the condition that the number of the third type indoor units is larger than or equal to that of the fourth type indoor units, determining that the optimal working mode under the current working condition is a refrigeration mode;

and under the condition that the number of the third type of indoor units is smaller than that of the fourth type of indoor units, determining the optimal working mode under the current working condition as a heating mode.

In some embodiments, the controller is further configured to:

determining the weighting weight of each indoor unit according to the refrigerating capacity of each indoor unit;

calculating the average value of the indoor return air temperatures of the third-type indoor units according to the weighted weights of the third-type indoor units and the indoor return air temperatures;

and calculating the indoor return air temperature average value of the fourth type indoor units according to the weighted weight and the indoor return air temperature of each fourth type indoor unit.

In some embodiments, the controller is further configured to:

receiving mode request signals which are not transmitted by a plurality of indoor units at the same time;

determining a working mode corresponding to the mode request signal received first as an optimal working mode;

Judging whether a working mode corresponding to a mode request signal received subsequently has mode conflict with an optimal working mode;

and in the case of mode conflict, executing the step of determining the optimal working mode under the current working condition according to the environmental parameters.

In a second aspect, an embodiment of the present application provides a multi-split air conditioner control method, which is applied to the multi-split air conditioner system, and the method includes:

the outdoor unit controller receives mode request signals sent by a plurality of indoor units at the same time and judges whether mode conflict exists according to mutual exclusion relation of the mode request signals;

under the condition that the outdoor unit controller has mode conflict, determining an optimal working mode under the current working condition according to the environmental parameters;

the outdoor unit controller sends an optimal working mode starting feedback signal to the first type indoor unit, and sends an air supply mode starting feedback signal and a mode conflict reminding to the second type indoor unit.

In a third aspect, an embodiment of the present application provides a computer readable storage medium, where an instruction is stored, where the instruction, when executed on any one of the above-mentioned devices, causes the device to execute any one of the above-mentioned multi-split air conditioner control methods.

In a fourth aspect, embodiments of the present application provide a chip, comprising: a processor and a memory; the memory is used for storing computer executing instructions, the processor is connected with the memory, and when the chip runs, the processor executes the computer executing instructions stored in the memory so that the chip executes any multi-split air conditioner control method.

In a fifth aspect, an embodiment of the present application provides a computer program product containing instructions that, when executed on any one of the above-mentioned apparatuses, cause an apparatus to perform any one of the above-mentioned multi-split air conditioner control methods.

The advantages of the second to fifth aspects may be referred to in any implementation manner of the first aspect, and are not described here. Further combinations of the present application may be made to provide further implementations based on the implementations provided in the above aspects.

Drawings

In order to more clearly illustrate the embodiments of the application or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a multi-split air conditioning system according to an embodiment of the present invention;

FIG. 2 is a flow chart of steps of a multi-split air conditioner control method according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of mutually exclusive relationships between indoor units according to an embodiment of the present invention;

FIG. 4 is a flowchart illustrating steps of another multi-split air conditioner control method according to an embodiment of the present invention;

FIG. 5 is a flowchart illustrating steps of another method for controlling a multi-split air conditioner according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of another multi-split air conditioning system according to an embodiment of the present invention;

FIG. 7 is a flowchart illustrating steps of another method for controlling a multi-split air conditioner according to an embodiment of the present invention;

FIG. 8 is a flowchart illustrating steps of another multi-split air conditioner control method according to an embodiment of the present invention;

FIG. 9 is a flowchart illustrating steps of another method for controlling a multi-split air conditioner according to an embodiment of the present invention;

FIG. 10 is a logic flow diagram of a mode conflict determination in accordance with an embodiment of the present invention;

FIG. 11 is a logic flow diagram of another mode conflict determination in an embodiment of the present invention;

FIG. 12 is a logic flow diagram of another mode conflict determination in an embodiment of the present invention;

fig. 13 is a flowchart illustrating steps of another multi-split air conditioner control method according to an embodiment of the present invention.

Reference numerals: 100. a multi-split air conditioning system; 11. an outdoor unit; 12. an indoor unit; 13. an air conditioner remote controller.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, unless otherwise indicated, the meaning of "a plurality" is two or more.

In the description of the present application, it should be noted that, unless explicitly stated and limited otherwise, the terms "connected," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art. In addition, when describing a pipeline, the terms "connected" and "connected" as used herein have the meaning of conducting. The specific meaning is to be understood in conjunction with the context.

In embodiments of the application, words such as "exemplary" or "such as" are used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" or "e.g." in an embodiment should not be taken as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "such as" is intended to present related concepts in a concrete fashion.

As described in the background art, in a multi-split air conditioning system, different indoor units may operate simultaneously, and different modes, such as cooling, heating, air supply, etc., may be set between the indoor units. When a plurality of indoor units work simultaneously, the outdoor unit needs to distribute refrigerant flow and cold and heat source capacity according to different requirements so as to meet the working requirements of each indoor unit. When the mode is judged, the existing multi-split air conditioning system generally judges the priority according to the sequence of entering the mode. Specifically, the mode priority set by the indoor unit of the system is higher, and the mode priority set by the indoor unit of the system is lower. If the mode set by the indoor unit of the later-entering system conflicts with the mode set by the indoor unit of the first-entering system, the system responds to the mode of the first-entering system, and does not respond to the mode of the later-entering system.

As an example, when one indoor unit enters the system first and sets a heating mode, the other indoor unit enters the system later and sets a cooling mode, and at this time, the system can respond to the heating mode set by the indoor unit entering the system first preferentially, so that the cooling requirement of the indoor unit entering the system later cannot be met. This situation may cause the indoor unit that later enters the system to fail to operate properly, even if the system fails, and the user cannot learn about the occurring situation.

In view of this problem, the inventors have proposed the technical idea of the present application: according to the current indoor and outdoor environment and the user requirements, the optimal working mode under the current working condition is automatically selected, the problems of operation failure and poor user experience caused by mode conflict are avoided, meanwhile, the efficiency of an air conditioning system can be improved, and the energy consumption is reduced.

For ease of understanding, the basic concepts of some terms or techniques involved in embodiments of the present application are first briefly described and illustrated.

Cooling mode: the compressor of the air conditioning system sucks the low-temperature low-pressure gaseous refrigerant evaporated by the evaporator into a compressor cavity, compresses the low-temperature low-pressure gaseous refrigerant into high-temperature high-pressure gaseous refrigerant, and enters the condenser. The high-temperature high-pressure gas refrigerant is condensed into high-temperature high-pressure liquid refrigerant in the condenser, then is throttled by a throttling element such as a capillary tube, and becomes low-temperature low-pressure liquid refrigerant, and finally returns to the compressor after entering the evaporator to evaporate, thereby completing the whole refrigeration cycle. The outdoor heat exchanger in the refrigerating mode is used as a condenser, and the indoor heat exchanger is used as an evaporator.

Dehumidification mode: the heat exchanger of the indoor unit of the air conditioning system is used as an evaporator to absorb heat, indoor air is condensed into water through the evaporator to be remained in the air conditioner, and then the water vapor is discharged through a drain pipe of the air conditioner, so that the effect of drying the indoor air is achieved.

Heating mode: the heating mode of the air conditioner is to transfer indoor heat to the outside by reversing the refrigerating cycle process of the air conditioner, thereby increasing the indoor temperature. The compressor sucks the low-temperature low-pressure refrigerant, discharges the high-temperature high-pressure refrigerant into the outdoor unit after compression and temperature rise, reduces the temperature of the refrigerant through heat dissipation, and then the refrigerant enters the indoor unit again to exchange heat with indoor air to transfer heat to the indoor air. Through such a process, the heating mode of the air conditioner can effectively raise the indoor temperature.

Air supply mode: after the indoor air is subjected to filtration, cooling or humidification and the like, the treated air is sent out through a fan, so that the indoor air quality and the comfort level are improved. The indoor unit sucks in indoor air through the fan and filters pollutants in the air through the filter screen. In the air supply mode, the air conditioner does not perform cooling or heating, and thus does not affect the indoor temperature. By the mode, the air supply mode of the air conditioner can improve indoor air quality and indoor comfort without adjusting temperature.

The embodiment of the application provides a multi-split air conditioning system, which comprises: an outdoor unit; the indoor unit comprises a plurality of indoor units connected in parallel; the outdoor unit includes a controller configured to: receiving mode request signals sent by a plurality of indoor units simultaneously, and judging whether mode conflict exists according to mutual exclusion relation among working modes corresponding to the mode request signals; under the condition of mode conflict, determining an optimal working mode under the current working condition according to the environmental parameters; and sending an optimal working mode starting feedback signal to the first type indoor unit, and sending an air supply mode starting feedback signal and a mode conflict reminding to the second type indoor unit.

The embodiments of the present application will be described in detail below with reference to the drawings attached to the specification.

Fig. 1 is a schematic diagram of a multi-split air conditioning system according to an exemplary embodiment of the present application. The following describes a multi-split air conditioning system provided in an embodiment of the present application with reference to fig. 1.

The multi-split air conditioning system 100 comprises an outdoor unit 11, an indoor unit 12 and an air conditioning remote controller 13, wherein each indoor unit in the indoor unit 12 is connected with the outdoor unit 11 through a refrigerant connecting pipeline.

The outdoor unit 11 is usually installed outdoors and is used for heat exchange in an indoor environment. In addition, in the embodiment of the present application, the air conditioner remote controller 13 refers to a device that can generate an operation control signal according to the command operation code and the timing signal, and instruct the multi-split air conditioning system to execute the control command. By way of example, the controller may be a central processing unit (central processing unit, CPU), a general purpose processor network processor (network processor, NP), a digital signal processor (digital signal processing, DSP), a microprocessor, a microcontroller, a programmable logic device (programmable logic device, PLD), or any combination thereof. The controller may also be any other device having processing functionality, such as a circuit, device or software module, for which embodiments of the application are not limited in any way.

In addition, the air conditioner remote controller 13 may be used to control the operation of each component in the multi-split air conditioning system 100, so that each component of the multi-split air conditioning system 100 operates to implement each predetermined function of the multi-split air conditioning system.

In some embodiments, the outdoor unit 11 includes a controller having a function of communicating with the controller 14 using, for example, infrared rays or other communication means.

The embodiment of the application provides a multi-split air conditioner control method, as shown in fig. 2, which is applied to the outdoor unit controller, and comprises the following steps:

s101: and receiving mode request signals sent by a plurality of indoor units simultaneously, and judging whether mode conflict exists or not according to mutual exclusion relation among working modes corresponding to the mode request signals.

The working modes of the indoor unit generally comprise four modes of refrigeration, heating, air supply and dehumidification. The four working modes have mutual exclusion relation, and the specific diagram is shown in the following figure, and as can be seen from the above, the air supply mode does not conflict with any mode, and the heating mode conflicts with the refrigeration mode and the dehumidification mode. In the multi-split air conditioning system, each indoor unit can send a working mode request signal to the outdoor unit controller, so that the air conditioning system can reasonably distribute the working modes of each indoor unit according to the requirements of users. However, when a plurality of indoor units simultaneously transmit different operation mode request signals, a problem of mode conflict may occur, resulting in an air conditioning system not operating normally. In each working period, the controller of the air conditioner external unit needs to receive the mode request signals from the indoor units in real time and store the signals in the buffer memory. The signals comprise information such as the type of the working mode of the indoor unit, the mode setting temperature, the wind speed and the like. Then, for the mode request signals transmitted by the plurality of indoor units stored in the cache, the signals need to be compared one by one to determine the mutual exclusion relationship between them.

When the mutual exclusion relation exists among different working modes, a mutual exclusion relation table can be established, the mutual exclusion relation among the working modes is recorded, and whether mode conflict exists or not is judged according to the table. The table may be a matrix, with rows representing respective modes of operation and columns representing respective indoor units. Each element in the figure represents a mutually exclusive relationship between a certain operation mode and a certain indoor unit, and may be represented by a number 1 or 0. Wherein, the number 1 indicates that the mutual exclusion relation exists between the working mode and the indoor unit, and the number 0 indicates that the mutual exclusion relation does not exist between the working mode and the indoor unit.

As an example, there is a triple-unit air conditioning system having three indoor units, i.e., an indoor unit a, an indoor unit B, and an indoor unit C. Four working modes in the system are a refrigeration mode, a heating mode, a dehumidification mode and an air supply mode respectively. According to the characteristics and the use conditions of different working modes, the mutual exclusion relation between the indoor unit and the working modes can be obtained, and the mutual exclusion relation is shown in fig. 3:

in the above figures, the cooling mode and the heating mode between the indoor unit a and the indoor unit C are mutually exclusive, because they both require the use of a refrigerant to achieve temperature control, while only one of them can be executed at the same time. Similarly, the dehumidification mode and the air supply mode between the indoor units B and C are mutually exclusive, because both the dehumidification mode and the air supply mode require air circulation, and only one of them can be executed at a time.

S102: and under the condition that the mode conflict exists, determining the optimal working mode under the current working condition according to the environmental parameters.

In the case of mode conflicts, in order to avoid operational failures and to improve the user experience, it is necessary to determine the best mode of operation in the current environment. In the process, the system monitors current environmental parameters, wherein the environmental parameters at least comprise outdoor temperature, indoor return air temperature, indoor humidity and the like, and judges according to preset judging rules, so that the optimal working mode is selected. Specifically, the system evaluates the applicability of various modes of operation based on the current environmental parameters, and then selects an optimal mode of operation. In the evaluation process, the system considers a plurality of factors, such as current environmental parameters, user requirements, system states and the like, so as to comprehensively judge the optimal working mode.

S103: and sending an optimal working mode starting signal to the first type indoor unit, and sending an air supply mode starting signal and a conflict reminding to the second type indoor unit.

The operation mode requested by the first type of indoor unit has been determined as the optimal operation mode, and thus it is necessary to transmit an optimal operation mode start signal thereto so that it operates in the optimal operation mode. And, for the second type indoor unit, since its mode request does not match the optimum operation mode, it cannot operate in the requested mode and needs to be switched to the air-sending mode. The air supply mode, although not fully satisfying the needs of the user, may provide an alternative to ensure the comfort of the indoor environment when a mode conflict occurs. When there is a mode conflict, the first type indoor unit has started the best working mode, and the second type indoor unit cannot start the required working mode due to the conflict with the best working mode, at this time, the starting air supply mode can provide basic air circulation and adjustment to keep ventilation and moderate temperature of the indoor environment, so as to temporarily meet the requirements of users. While the air supply mode may not provide accurate temperature control as in the cooling or heating modes, it may be better for some users than without the air conditioner. Meanwhile, in order to remind the user of the mode conflict, a conflict prompt needs to be sent to the user through module display or other modes so that the user can know the current working state. By the mode, when the system has mode conflict, the stable operation of the system and the comfortable experience of a user can be ensured by selecting the switching between the optimal working mode and the air supply mode.

Through the embodiment, the working mode conflict between the indoor units can be effectively avoided, and the overall efficiency and stability of the air conditioning system are improved. The optimal working mode is determined according to the environmental parameters, so that the working mode of the air conditioning system can be adjusted more intelligently, energy is saved, and consumption is reduced. The indoor units are divided into a first type and a second type, and different measures are taken for the indoor units of different types, so that the running state of the air conditioning system can be managed more finely. The conflict prompt is sent, so that the user can be informed of the mode conflict in time, and the safety of the system and the use experience of the user are improved.

In some embodiments, the controller of the outdoor unit is further configured to: and determining the matched indoor unit of the mode request signal and the optimal working mode as the first type indoor unit, and determining the unmatched indoor unit as the second type indoor unit.

In a multi-split air conditioning system, different indoor units may send different operation mode request signals. In these request signals, mutually exclusive relationships may exist, resulting in pattern conflicts. To solve this problem, it is necessary to find an optimal operation mode so that all indoor units can operate normally without collision. Therefore, the system needs to determine which indoor units should be set to the first type and which should be set to the second type by matching the mode request signal with the optimal operation mode.

Specifically, the system may first calculate the optimal mode of operation based on the current environmental conditions and user requirements. Then, the system matches the mode request signals with the optimal operation mode while the indoor unit transmits these signals. If the request signal sent by one of the indoor units matches the optimal operation mode, then that indoor unit is determined to be of the first type. If the request signal sent by one of the indoor units does not match the optimal operation mode, then that indoor unit is determined to be of the second type.

The indoor units are divided into the first type and the second type, so that different requirements of the indoor units can be better met. The first type of indoor units will be prioritized because their request signals match the best mode of operation, ensuring proper operation of the system. The second type indoor unit needs to be set after the first type indoor unit is set, so as to avoid mode conflict. Thus, the request of the indoor unit can be processed more flexibly, and the efficiency and the stability of the system are improved.

It should be noted that the division of the indoor units into the first type and the second type is not always the same, and their types may change in different working cycles. Therefore, the system needs to constantly monitor and analyze in order to dynamically adjust the type of indoor unit to better accommodate different operating conditions and user needs.

In some embodiments, as shown in fig. 4, S102 specifically includes:

s1021: the method comprises the steps of determining the type of the mode conflict, wherein the type of the mode conflict comprises a refrigeration mode conflict and a heating mode conflict, and a dehumidification mode conflict and a heating mode conflict.

Determining the type of the mode conflict refers to controlling whether the modes corresponding to different indoor unit requests need to be judged to be in conflict or not, so that corresponding measures are taken to solve the problem when the mode conflict exists. In this embodiment, the types of mode conflicts include a cooling mode conflict and a heating mode conflict, and a dehumidifying mode conflict and a heating mode conflict. Specifically, if there is a request for cooling and heating by the indoor unit at the same time, or a request for dehumidification and heating, a mode conflict occurs.

S1022: and under the condition that the mode conflict type is that the refrigeration mode and the heating mode conflict, determining the optimal working mode under the current working condition according to the outdoor temperature and the indoor return air temperature.

Under the condition that the controller judges that the current mode conflict is the conflict between the refrigerating mode and the heating mode, namely that some rooms have heating requirements, and some rooms have refrigerating requirements, the controller needs to judge that under the current actual condition, which working mode is selected as the best working mode can meet the requirements of most users and the energy-saving requirements.

As an example, the user in room a triggers the heating mode request signal due to false touch, while at the same time, the user in room B triggers the cooling mode request signal, and the mode request signals of room a and room B are simultaneously received by the controller of the outdoor unit, and in order to eliminate the false touch in room a, the controller of the outdoor unit needs to determine the best working mode under the current working condition according to the outdoor temperature and the indoor return air temperature, i.e. the cooling mode request signal of room B is screened out.

S1023: and under the condition that the mode conflict type is that the dehumidification mode and the heating mode conflict, determining the optimal working mode under the current working condition according to the outdoor temperature, the indoor humidity and the indoor return air temperature.

Similarly, when the controller determines that the current mode conflict is a conflict between a dehumidification mode and a heating mode, that is, when some rooms have heating requirements and some rooms have dehumidification requirements, it needs to determine which working mode is selected as the best working mode to meet the requirements of most users and the energy-saving requirements in the current actual situation.

As an example, the user in the room C triggers the dehumidification mode request signal due to the false touch, and at the same time, the user in the room D triggers the refrigeration mode request signal, and the mode request signals of the room C and the room D are simultaneously received by the controller of the outdoor unit, and in order to eliminate the false touch in the room C, the controller of the outdoor unit needs to determine the optimal working mode under the current working condition according to the outdoor temperature, the indoor humidity and the indoor return air temperature, i.e., the refrigeration mode request signal of the room D is screened out.

In some embodiments, as shown in fig. 5, S1022 specifically includes:

s10221: and under the condition that the outdoor temperature is greater than or equal to a preset upper temperature limit threshold, determining that the optimal working mode under the current working condition is a refrigeration mode.

The change in outdoor temperature is one of the main factors affecting the regulation of the operation mode of the air conditioning system. Therefore, by setting the preset upper temperature limit threshold and lower temperature limit threshold, the system can judge the current environment working condition according to the outdoor temperature, so that the optimal working mode is selected. In the case that the outdoor temperature is greater than or equal to the preset upper temperature threshold, the system may select the cooling mode as the optimal operation mode. This is because the outdoor temperature is higher and the cooling mode can lower the indoor temperature faster, providing a more comfortable environment. Therefore, the refrigeration mode is more in line with the actual use requirement under the current scene, and the optimal working mode under the current working condition is determined.

As an example, the logic determination process is shown in the figure, firstly, the outdoor unit receives the cooling mode request signal sent by the a indoor unit in the a room and the heating mode request signal sent by the B indoor unit in the B room at the same time, and when the preset upper temperature threshold is 22 ℃, the outdoor unit collects the outdoor temperature Ta, and if the outdoor temperature Ta reaches or exceeds 22 ℃, the optimal working mode under the current working condition is determined to be the cooling mode, because the mode request signal sent by the a indoor unit is matched with the optimal working mode, the a indoor unit is determined to be the first type indoor unit, and because the mode request signal sent by the B indoor unit is not matched with the optimal working mode, the B indoor unit is determined to be the second type indoor unit. And then the outdoor unit works according to the parameters of the refrigeration mode, sends a refrigeration mode starting feedback signal to the indoor unit a, and sends an air supply mode starting feedback signal and a mode conflict prompt to the indoor unit b.

In some embodiments, the outdoor unit may be a combination of modules, as shown in fig. 6, that is, a plurality of outdoor units are combined into a refrigerant system, in which case, the outdoor temperature Ta collected by the outdoor unit is an average value of Ta1, ta2, ta3 … TaN collected by N outdoor units, that is, ta= (ta1+ta2+ta3+ … +tan)/N.

S10222: and under the condition that the outdoor temperature is less than or equal to a preset temperature lower limit threshold value, determining the optimal working mode under the current working condition as a heating mode.

And under the condition that the outdoor temperature is less than or equal to a preset temperature lower limit threshold value, the system can select a heating mode as an optimal working mode. Because the outdoor temperature is lower, the heating mode can more quickly improve the indoor temperature and provide a more comfortable environment. Therefore, the heating mode is more in line with the actual use requirement under the current scene, and the optimal working mode under the current working condition is determined.

As an example, the logic determination process is shown in the figure, firstly, the outdoor unit receives the cooling mode request signal sent by the a indoor unit in the a room and the heating mode request signal sent by the B indoor unit in the B room at the same time, and when the preset temperature lower limit threshold is 18 ℃, the outdoor unit collects the outdoor temperature Ta, and if the outdoor temperature Ta reaches or is lower than 18 ℃, the optimal operation mode under the current working condition is determined to be the heating mode, and since the mode request signal sent by the B indoor unit is matched with the optimal operation mode, the B indoor unit is determined to be the first type indoor unit, and since the mode request signal sent by the a indoor unit is not matched with the optimal operation mode, the a indoor unit is determined to be the second type indoor unit. And then the outdoor unit works according to the parameters of the heating mode, sends a heating mode starting feedback signal to the indoor unit b, and sends an air supply mode starting feedback signal and a mode conflict prompt to the indoor unit a.

S10223: and under the condition that the outdoor temperature is in the temperature upper limit threshold value and the temperature lower limit threshold value, determining the optimal working mode under the current working condition according to the indoor return air temperature.

When the outdoor temperature of the temperature chamber is between the upper and lower thresholds, the outdoor temperature does not determine the optimal operation mode well. The indoor return air temperature Ti can reflect the indoor temperature, so the main purpose of the air conditioning system is to adjust the indoor temperature, and therefore, the optimal working mode needs to be selected according to the indoor return air temperature, because the indoor return air temperature is also an important factor affecting the optimal working mode. Therefore, when the temperature is between the upper limit threshold and the lower limit threshold, the optimal working mode is selected according to the indoor return air temperature, so that the indoor temperature can be regulated more accurately, and the efficiency and the comfort of the air conditioning system are improved.

In some embodiments, as shown in fig. 7, S1023 specifically includes:

s10231: and under the condition that the indoor humidity is greater than or equal to a preset humidity threshold value, determining the optimal working mode under the current working condition as a dehumidification mode.

When the conflict between the heating mode and the dehumidifying mode occurs, the high humidity brings discomfort to people and possibly even causes health problems, so that the request for dehumidifying the rooms needs to be prioritized, namely, firstly, the indoor humidity of each room in the multi-split system is judged, and the optimal working mode under the current working condition is determined to be the dehumidifying mode as long as the indoor humidity is greater than or equal to a preset humidity threshold value.

As an example, the logic determination process is shown in the figure, and the outdoor unit receives the dehumidification mode request signal sent by the indoor unit C in the room C and the heating mode request signal sent by the indoor unit D in the room D at the same time. Subsequently, the ambient humidity THMC and THMD in the C room and the D room are acquired,

when the preset humidity threshold is 80%, if the THMC reaches or exceeds 80%, determining that the optimal operation mode under the current working condition is a dehumidification mode, determining the c-indoor unit as the first-type indoor unit because the mode request signal transmitted by the c-indoor unit is matched with the optimal operation mode, and determining the d-indoor unit as the second-type indoor unit because the mode request signal transmitted by the d-indoor unit is not matched with the optimal operation mode. And then the outdoor unit works according to the parameters of the dehumidification mode, sends a dehumidification mode starting feedback signal to the indoor unit c, and sends an air supply mode starting feedback signal and a mode conflict prompt to the indoor unit d.

S10232: and under the condition that the indoor humidity is smaller than a preset humidity threshold value and the outdoor temperature is larger than or equal to a preset temperature upper limit threshold value, determining that the optimal working mode under the current working condition is a dehumidification mode.

When the conflict between the heating mode and the dehumidifying mode occurs, but the indoor humidity is smaller than the preset humidity threshold, namely the humidity of each room does not affect the human body at present, therefore, only the temperature is needed to be taken as a consideration factor, the judgment logic is used for preferentially judging the influence of the outdoor temperature, in this case, the indoor air is drier, the outdoor temperature is higher, and the indoor temperature and the humidity are easy to be excessively high. The use of the cooling mode in this case may allow the indoor temperature to be lower, but the indoor humidity to be further lowered, which may be uncomfortable. And the dehumidification mode is selected, so that the indoor air is more comfortable by reducing the indoor humidity. Therefore, the dehumidification mode is more in line with the actual use requirement under the current scene, and the optimal working mode under the current working condition is determined.

S10233: under the condition that the indoor humidity is smaller than a preset humidity threshold value and the outdoor temperature is smaller than or equal to a preset temperature lower limit threshold value, determining that the optimal working mode under the current working condition is a heating mode;

s10234: and under the condition that the indoor humidity is smaller than a preset humidity threshold value and the outdoor temperature is in a temperature upper limit threshold value and temperature lower limit threshold value interval, determining an optimal working mode under the current working condition according to the indoor return air temperature.

In some embodiments, as shown in fig. 8, S10223 specifically includes:

s102231: and determining the indoor unit with the indoor return air temperature being greater than or equal to a preset temperature upper limit threshold value as a third type indoor unit, and determining the indoor unit with the indoor return air temperature being less than or equal to the preset temperature upper limit threshold value as a fourth type indoor unit.

When the outdoor temperature is within the upper temperature limit threshold and the lower temperature limit threshold, it is described that the outdoor temperature is not cold or hot at this time, and therefore, it is necessary to perform an auxiliary determination in combination with the indoor return air temperature feeling Ti at this stage. In the process, effective data need to be screened out, the indoor machine with the indoor return air temperature being greater than or equal to the preset upper temperature limit threshold value and the requested indoor machine with the mode type being the refrigeration mode is determined to be the third type indoor machine, the indoor return air temperature being less than or equal to the preset lower temperature limit threshold value and the indoor machine with the requested mode type being the heating mode is determined to be the fourth type indoor machine.

It should be noted that the same indoor unit may be either a first type indoor unit or a third type indoor unit, because the first type and the third type are determination results belonging to different stages, and the second type and the fourth type are the same.

As an example, the preset upper temperature threshold is 22 ℃ and the preset lower temperature threshold is 18 ℃. The following are the requested information for each room and the indoor return air temperature:

room a: the indoor unit request mode is refrigeration, and the indoor return air temperature is 25 ℃.

Room B: and b, the indoor unit request mode is refrigeration, and the indoor return air temperature is 24 ℃.

Room C: and c, heating the indoor unit in a request mode, wherein the indoor return air temperature is 17 ℃.

Room D: and d, the indoor unit request mode is heating, and the indoor return air temperature is 16 ℃.

From the above conditions, the following conclusions can be drawn: the a and b indoor units are determined as the third type indoor units, and the c and d indoor units are determined as the fourth type indoor units.

S102232: and determining a difference value calculation result of the indoor return air temperature average value of the third type indoor unit and a preset temperature upper limit threshold value as a first calculation result, and determining a difference value calculation result of the indoor return air temperature average value of the fourth type indoor unit and a preset temperature lower limit threshold value as a second calculation result.

It should be noted that, when there are a plurality of indoor units of the third type and the fourth type, it is necessary to calculate an average value of the indoor return air temperature of the third type and an average value of the indoor return air temperature of the fourth type, and take an absolute value of a difference value calculated result between the average value of the indoor return air temperature of the third type and a preset upper temperature threshold value as a first calculation result, and an absolute value of a difference value calculated result between the average value of the indoor return air temperature of the fourth type and a preset lower temperature threshold value as a second calculation result.

As an example, continuing with the above embodiment, the third type indoor unit includes a and b, and then the indoor return air temperature average value of the third type indoor unit is 24.5 ℃, and then the indoor return air temperature average value of the third type indoor unit is 14.5 ℃, and then the first calculation result is 23.5 ℃ -22 ℃ =2.5 ℃, and the second calculation result is |16.5 ℃ -18 ℃ |=1.5 ℃.

S102233: and under the condition that the first calculation result is smaller than the second calculation result, determining the optimal working mode under the current working condition as a heating mode.

When the first calculation result is larger than the second calculation result, the difference between the average indoor return air temperature of the third type indoor unit and the preset upper temperature limit threshold is larger than the difference between the average indoor return air temperature of the fourth type indoor unit and the preset lower temperature limit threshold, and the optimal working mode is a refrigeration mode at the moment so as to adjust the indoor temperature to be reduced; otherwise, when the first calculation result is smaller than the second calculation result, the difference between the average indoor return air temperature of the fourth type indoor unit and the preset temperature lower limit threshold is larger than the difference between the average indoor return air temperature of the third type indoor unit and the preset temperature upper limit threshold, and the optimal working mode is a heating mode so as to adjust the indoor temperature to rise. A room with a large difference would therefore need to reach the comfort temperature faster, so the requested mode of operation of that room should be selected preferentially.

In some embodiments, when the first calculation result is equal to the second calculation result, any one of the operation modes may be adopted, but in order to make the determination result more accurate, in the case that the first calculation result is equal to the second calculation result, further determination may be performed according to the number of the third-type indoor units and the fourth-type indoor units, that is, the operation mode corresponding to the one with the greater number is determined as the optimal operation mode.

In some embodiments, when the number of the third type indoor units and the fourth type indoor units are equal, the calculation may be performed according to the cooling capacity of the indoor units when calculating the average value of the indoor return air temperature, as shown in fig. 9, which specifically includes:

s201: determining the weighting weight of each indoor unit according to the refrigerating capacity of each indoor unit;

s202: calculating the average value of the indoor return air temperatures of the third-type indoor units according to the weighted weights of the third-type indoor units and the indoor return air temperatures;

s203: and calculating the indoor return air temperature average value of the fourth type indoor units according to the weighted weight and the indoor return air temperature of each fourth type indoor unit.

First, it is necessary to determine the cooling capacity of each indoor unit, and then, to calculate the weighting of each indoor unit by weighting the cooling capacity of each indoor unit. And secondly, calculating the average value of the indoor return air temperature of the third-type indoor units according to the weighted weight and the indoor return air temperature of each third-type indoor unit.

As an example, assuming that there are two third type indoor units, the cooling capacity of the indoor unit a is 2kW and the cooling capacity of the indoor unit b is 3kW, the weighting weights of the third type indoor units may be respectively:

weighting weight of indoor unit a: 2/(2+3) =0.4.

Weighting weight of indoor unit b: 3/(2+3) =0.6.

The return air temperatures of the indoor units a and b are respectively tia=24 ℃, tib=26 ℃, and the weighting weights of the indoor units a and b are respectively 0.3 and 0.7, so that the average value of the indoor return air temperatures of the third type of indoor units is:

Ti3_avg＝0.4×24+0.6×26＝25.4℃。

similarly, there are three fourth-type indoor units, where indoor return air temperatures are respectively tic=14 ℃, tid=15 ℃, tie=16 ℃, and their weighting weights are respectively 0.2, 0.3 and 0.5, and then the average indoor return air temperatures of the fourth-type indoor units are:

Ti4_avg＝0.2×18+0.3×19+0.5×20＝15.3℃。

in some embodiments, the present application will be described with reference to fig. 10, in which the judgment logic when a plurality of indoor units are turned on simultaneously and a conflict of modes of cooling and heating occurs is described. First, the indoor units a and B simultaneously transmit a cooling mode request and a heating mode request to the outdoor unit, and the outdoor unit determines that a mode conflict occurs after receiving the cooling mode request and the heating mode request. Then, the outdoor unit obtains the outdoor temperature through the sensor, and determines an optimal working mode according to a specific section where the outdoor temperature is located, namely, when the outdoor temperature is less than or equal to 18 ℃, the optimal working mode is a heating mode, so that the indoor unit A starts an air supply mode, the indoor unit B starts a heating mode, and when the outdoor temperature is greater than or equal to 22 ℃, the optimal working mode is a cooling mode, so that the indoor unit A starts the cooling mode, and the indoor unit B starts the air supply mode.

In some embodiments, the present application will be described with reference to FIG. 11, which illustrates the best mode decision logic for outdoor temperatures in the range of 18℃ to 22℃. Firstly, indoor return air temperatures TIA and TIB acquired by an indoor unit A and an indoor unit B are acquired indoors, then a first calculation result a and a second calculation result B are calculated according to the TIA and the TIB, then an optimal working mode is determined according to the comparison relation between the sizes of the first calculation result a and the second calculation result B, namely, when the first calculation result a is smaller than the second calculation result B, the optimal working mode is a heating mode, so that the indoor unit A starts an air supply mode, and when the indoor unit B starts a heating mode, namely, when the first calculation result a is larger than or equal to the second calculation result B, the optimal working mode is a refrigerating mode, so that the indoor unit A starts the refrigerating mode, and the indoor unit B starts the air supply mode.

In some embodiments, the present application will be described with reference to fig. 12, in which the judgment logic when a plurality of indoor units are turned on simultaneously and a mode conflict of dehumidification and heating occurs is described. First, the indoor units a and B simultaneously transmit a dehumidification mode request and a heating mode request to the outdoor unit, and the outdoor unit determines that a mode conflict occurs after receiving the dehumidification mode request and the heating mode request. Then, the outdoor unit acquires indoor humidity THMA and THMB acquired by the indoor units a and B, determines whether THMA and THMB are greater than a preset threshold, and if so, the optimal operation mode is a dehumidification mode, so that the indoor unit a starts the dehumidification mode, the indoor unit B starts the air supply mode, and the humidity value is reduced below the threshold, and then, determines according to the determination logic shown in fig. 11.

In some embodiments, the indoor units may not be turned on simultaneously, so the outdoor unit may not receive the mode request signal simultaneously, and the processing steps of the mode request signal sent non-simultaneously are as shown in fig. 13, which specifically includes:

s301: receiving mode request signals which are not transmitted by a plurality of indoor units at the same time;

s302: determining a working mode corresponding to the mode request signal received first as an optimal working mode;

s303: judging whether a working mode corresponding to a mode request signal received subsequently has mode conflict with an optimal working mode;

s304: and in the case of mode conflict, executing the step of determining the optimal working mode under the current working condition according to the environmental parameters.

The air conditioning system is required to continuously receive mode request signals of the indoor units during operation, and an optimal operation mode is determined according to the signals. When the request signals of a plurality of indoor units are not simultaneously transmitted, it is necessary for the air conditioning system to be able to judge the priority of each request signal so as to be able to quickly respond to the optimal operation mode. First, when the air-conditioning system receives a first mode request signal, it determines the operation mode corresponding to the request signal as the current optimal operation mode. Then, the air conditioning system operates according to the optimal operation mode, and when the subsequent mode request signals arrive, the system checks whether the operation mode corresponding to the request signals conflicts with the current optimal operation mode. If there is a conflict, the system needs to determine the best mode of operation under the current operating conditions again based on the environmental parameters.

As an example, assume that the air conditioning system first receives a mode request signal of the indoor unit, and the corresponding operation mode thereof is a heating mode. Accordingly, the air conditioning system may determine the heating mode as the current optimal operation mode. However, if a subsequent request signal arrives from an indoor unit requesting a cooling mode, there is a conflict with the current optimal operation mode. At this time, the air conditioning system will re-determine the optimal working mode according to the environmental parameters, so as to ensure that the system can stably operate. The process is as in the above embodiment, and thus will not be described in detail.

In some embodiments, the controller includes a processor, and optionally, a memory and a communication interface coupled to the processor. The processor, the memory and the communication interface are connected by a bus.

The processor may be a central processing unit (central processing unit, CPU), a general purpose processor Network Processor (NP), a digital signal processor (digital signalprocessing, DSP), a microprocessor, a microcontroller, a programmable logic device (programmable logic device, PLD), or any combination thereof. The processor may also be any other means for performing a processing function, such as a circuit, device, or software module. The processor may also include multiple CPUs, and the processor may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. A processor herein may refer to one or more devices, circuits, or processing cores for processing data (e.g., computer program instructions).

The memory may be a read-only memory (ROM) or other type of static storage device, a random access memory (random access memory, RAM) or other type of dynamic storage device that may store static information and instructions, or an electrically erasable programmable read-only memory (electricallyerasable programmable read-only memory, EEPROM), a compact disc (compact disc read-only memory, CD-ROM) or other optical disk storage, optical disk storage (including compact disc, laser disc, optical disc, digital versatile disc, blu-ray disc, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer, as embodiments of the application are not limited in this regard. The memory may be separate or integrated with the processor. Wherein the memory may contain computer program code. The processor is used for executing computer program codes stored in the memory, so that the multi-split air conditioner control method provided by the embodiment of the application is realized.

The communication interface may be used to communicate with other devices or communication networks (e.g., ethernet, radio access network (radioaccess network, RAN), wireless local area network (wireless local areanetworks, WLAN), etc.). The communication interface may be a module, a circuit, a transceiver, or any device capable of enabling communication.

The bus may be a peripheral component interconnect standard (peripheral component interconnect, PCI) bus or an extended industry standard architecture (extended industry standard architecture, EISA) bus, or the like. The buses may be divided into address buses, data buses, control buses, etc.

The embodiment of the invention also provides a computer readable storage medium, which comprises computer execution instructions, and when the computer execution instructions run on a computer, the computer is caused to execute the multi-split air conditioner control method provided by the embodiment.

The embodiment of the invention also provides a chip, which comprises: a processor and a memory; the memory is used for storing computer execution instructions, the processor is connected with the memory, and when the chip runs, the processor executes the computer execution instructions stored in the memory, so that the chip executes the multi-split air conditioner control method provided by the embodiment.

The embodiment of the invention also provides a computer program product which can be directly loaded into a memory and contains software codes, and the computer program product can realize the multi-split air conditioner control method provided by the embodiment after being loaded and executed by a computer.

In the description of the present specification, a particular feature, structure, material, or characteristic may be combined in any suitable manner in one or more embodiments or examples.

The foregoing is merely illustrative of the present invention, and the present invention is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (10)

1. A multi-split air conditioning system, the system comprising:

an outdoor unit;

the indoor unit comprises a plurality of indoor units connected in parallel;

the outdoor unit includes a controller configured to:

receiving mode request signals sent by a plurality of indoor units simultaneously, and judging whether mode conflict exists according to mutual exclusion relation among working modes corresponding to the mode request signals;

Under the condition of mode conflict, determining an optimal working mode under the current working condition according to the environmental parameters;

and sending an optimal working mode starting feedback signal to the first type indoor unit, and sending an air supply mode starting feedback signal and a mode conflict reminding to the second type indoor unit.

2. The multi-split air conditioning system of claim 1, wherein the controller is further configured to:

the indoor units with the working modes corresponding to the mode request signals and the optimal working modes are matched, and the indoor units are determined to be the first type indoor units;

and determining the unmatched indoor units of the working mode corresponding to the mode request signal and the optimal working mode as the second type indoor units.

3. The multi-split air conditioning system of claim 1, wherein the controller is further configured to:

determining the type of the mode conflict, wherein the type of the mode conflict comprises a refrigeration mode conflict and a heating mode conflict, and a dehumidification mode conflict and a heating mode conflict;

under the condition that the mode conflict type is that the refrigerating mode and the heating mode conflict, determining an optimal working mode under the current working condition according to the outdoor temperature and the indoor return air temperature;

And under the condition that the mode conflict type is that the dehumidification mode and the heating mode conflict, determining an optimal working mode under the current working condition according to the outdoor temperature, the indoor humidity and the indoor return air temperature.

4. The multi-split air conditioning system of any of claims 1-3, further comprising a first temperature sensor and at least one second temperature sensor;

the controller is further configured to:

acquiring outdoor temperature through the first temperature sensor, and acquiring indoor return air temperature of each indoor unit through the at least one second temperature sensor;

under the condition that the outdoor temperature is greater than or equal to a preset upper temperature threshold, determining that the optimal working mode under the current working condition is a refrigeration mode;

under the condition that the outdoor temperature is smaller than or equal to a preset temperature lower limit threshold value, determining an optimal working mode under the current working condition as a heating mode;

and under the condition that the outdoor temperature is located in the temperature upper limit threshold value and the temperature lower limit threshold value, determining an optimal working mode under the current working condition according to the indoor return air temperature.

5. The multi-split air conditioning system of claim 4, further comprising at least one humidity sensor;

The controller is further configured to:

acquiring indoor humidity of each indoor unit through the at least one humidity sensor;

under the condition that the indoor humidity is greater than or equal to a preset humidity threshold value, determining an optimal working mode under the current working condition as a dehumidification mode;

under the condition that the indoor humidity is smaller than a preset humidity threshold value and the outdoor temperature is larger than or equal to a preset temperature upper limit threshold value, determining that the optimal working mode under the current working condition is a dehumidification mode;

under the condition that the indoor humidity is smaller than a preset humidity threshold value and the outdoor temperature is smaller than or equal to a preset temperature lower limit threshold value, determining an optimal working mode under the current working condition as a heating mode;

and under the condition that the indoor humidity is smaller than a preset humidity threshold value and the outdoor temperature is located between the temperature upper limit threshold value and the temperature lower limit threshold value, determining an optimal working mode under the current working condition according to the indoor return air temperature.

6. The multi-split air conditioning system of claim 5, wherein the controller is further configured to:

determining the indoor unit with the indoor return air temperature being greater than or equal to a preset temperature upper limit threshold value as a third type indoor unit;

Determining the indoor unit with the indoor return air temperature smaller than or equal to a preset temperature upper limit threshold value as a fourth type indoor unit;

determining a difference value calculation result of the indoor return air temperature average value of the third type indoor unit and a preset temperature upper limit threshold value as a first calculation result, and determining a difference value calculation result of the indoor return air temperature average value of the fourth type indoor unit and a preset temperature lower limit threshold value as a second calculation result;

and under the condition that the first calculation result is smaller than the second calculation result, determining the optimal working mode under the current working condition as a heating mode.

7. The multi-split air conditioning system of claim 6, wherein the controller is further configured to:

acquiring the number of the third type indoor units and the number of the fourth type indoor units under the condition that the first calculation result is equal to the second calculation result;

under the condition that the number of the third type indoor units is larger than or equal to that of the fourth type indoor units, determining that the optimal working mode under the current working condition is a refrigeration mode;

And under the condition that the number of the third type indoor units is smaller than that of the fourth type indoor units, determining the optimal working mode under the current working condition as a heating mode.

8. The multi-split air conditioning system of claim 6, wherein the controller is further configured to:

determining the weighting weight of each indoor unit according to the refrigerating capacity of each indoor unit;

calculating the average value of the indoor return air temperatures of the third type indoor units according to the weighted weights of the third type indoor units and the indoor return air temperatures;

and calculating the indoor return air temperature average value of each fourth type indoor unit according to the weighted weight and the indoor return air temperature of each fourth type indoor unit.

9. The multi-split air conditioning system of any of claims 1, 2, 3, 5, 6, 7, wherein the controller is further configured to:

receiving mode request signals which are not transmitted by a plurality of indoor units at the same time;

determining a working mode corresponding to the mode request signal received first as an optimal working mode;

judging whether a working mode corresponding to a mode request signal received subsequently has mode conflict with the optimal working mode;

And in the case of mode conflict, executing the step of determining the optimal working mode under the current working condition according to the environmental parameters.

10. A multi-split air conditioner control method, which is applied to the multi-split air conditioner system as claimed in any one of claims 1 to 9, and comprises the following steps:

the outdoor unit controller receives mode request signals sent by a plurality of indoor units at the same time, and judges whether mode conflict exists according to mutual exclusion relation of the mode request signals;

under the condition that the outdoor unit controller has mode conflict, determining an optimal working mode under the current working condition according to the environmental parameters;

and the outdoor unit controller sends an optimal working mode starting feedback signal to the first type indoor unit, and sends an air supply mode starting feedback signal and a mode conflict prompt to the second type indoor unit.