Control method of air conditioning system, controller, air conditioning system and medium

Abstract

The embodiment of the invention provides a control method of an air conditioning system, a controller, the air conditioning system and a medium, the air conditioning system comprises an evaporator, a condenser, a compressor and a plate heat exchanger, the plate heat exchanger is provided with a heat exchange main path, a first heat exchange auxiliary path and a second heat exchange auxiliary path, and one end of the condenser communicates with an exhaust port of the compressor; the end, close to the heat exchange main path, of the main path electronic expansion valve communicates with an enthalpy increasing opening of the compressor through the first auxiliary path electronic expansion valve and the first heat exchange auxiliary path, and further communicates with an air return opening of the compressor through the second auxiliary path electronic expansion valve and the second heat exchange auxiliary path. Two-stage enthalpy spraying control of the plate heat exchanger is adopted, under low-load refrigeration, the first auxiliary path electronic expansion valve can be turned off, the second auxiliary path electronic expansion valve can be turned on, and the capacity and noise reduction are guaranteed; and meanwhile, the refrigerant circulation amount of the main pipeline is reduced, the power and current are reduced, and the energy-saving and electricity-saving effects are achieved.

Description

Technical Field

[0001] The present application relates to the technical field of air conditioners, and in particular to a control method, a controller, an air conditioning system and a medium for an air conditioning system. Background Art

[0002] In the related technology, some air-conditioning heat pump units adopt injection enthalpy control, which is mainly achieved by taking liquid refrigerant on the high-pressure side, and then injecting it into the medium-pressure chamber of the compressor after throttling by the electronic expansion valve and heat exchange by the plate heat exchanger. The injection enthalpy system can be used to increase the system subcooling and air supply volume, thereby improving the capacity.

[0003] However, for the traditional jet enthalpy increase system, under low load conditions, the circulation volume of the refrigerant will be greatly reduced. Although the supercooling degree is increased, the mass flow rate is reduced. At this time, the capacity of the jet enthalpy system to increase is very limited, but the system power is increased a lot, resulting in a large current and increased heat generation of the main control board. Under high-temperature extreme refrigeration conditions, it neither saves electricity nor reduces the reliability and life of the main control board due to the large heat generation.

[0004] In addition, under high temperature and low load conditions, if the spray enthalpy system is turned off, the system subcooling will be reduced, which may easily cause the refrigerant to be in a gas-liquid two-phase state when entering the indoor unit's electronic expansion valve, and the indoor unit system may have a loud refrigerant flushing sound. Summary of the invention

[0005] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a control method, a controller, an air conditioning system and a medium for an air conditioning system, which ensures the cooling capacity and noise reduction under low load conditions, and reduces power and current to achieve energy saving and power saving effects.

[0006] In a first aspect, an embodiment of the present application provides an air conditioning system, comprising:

[0007] Evaporators, condensers and compressors;

[0008] A plate heat exchanger, a main electronic expansion valve, a first auxiliary electronic expansion valve and a second auxiliary electronic expansion valve, wherein the plate heat exchanger is provided with a main heat exchange path, a first auxiliary heat exchange path and a second auxiliary heat exchange path, one end of the condenser is connected to the exhaust port of the compressor, and the other end is connected to the evaporator through the main electronic expansion valve and the main heat exchange path, one end of the main electronic expansion valve close to the main heat exchange path is connected to the enthalpy increase port of the compressor through the first auxiliary electronic expansion valve and the first heat exchange auxiliary path, and is also connected to the return air port of the compressor through the second auxiliary electronic expansion valve and the second heat exchange auxiliary path;

[0009] Wherein, under low-load refrigeration conditions, the main electronic expansion valve and the second auxiliary electronic expansion valve are both in an open state, and the first auxiliary electronic expansion valve is in a closed state.

[0010] According to some embodiments of the present application, the air-conditioning system also includes a first auxiliary capillary and a second auxiliary capillary, the first auxiliary capillary is arranged on a side of the first auxiliary circuit electronic expansion valve away from the first heat exchange auxiliary circuit, and the second auxiliary capillary is arranged on a side of the second auxiliary circuit electronic expansion valve away from the second heat exchange auxiliary circuit.

[0011] According to some embodiments of the present application, the air-conditioning system also includes a gas-liquid separator. In a cooling mode or a dehumidification mode, the gas phase input port of the gas-liquid separator is connected to the evaporator and the second heat exchange auxiliary circuit, and the liquid phase output port of the gas-liquid separator is connected to the return air port of the compressor.

[0012] According to some embodiments of the present application, the air-conditioning system also includes an oil separator, the input port of the oil separator is connected to the exhaust port of the compressor, the oil output port of the oil separator is connected to the return air port of the compressor, and the refrigerant output port of the oil separator is connected to the condenser.

[0013] According to some embodiments of the present application, the air conditioning system further includes a four-way valve, which is respectively connected to the exhaust port and the return port of the evaporator, the condenser, and the compressor.

[0014] In a second aspect, an embodiment of the present application provides a control method for an air-conditioning system, which is applied to the air-conditioning system according to any one of claims 1 to 5; the method comprises:

[0015] Obtaining operating parameters of the air conditioning system;

[0016] Determining that the air conditioning system is in a low-load refrigeration condition according to the operating parameters, opening the main electronic expansion valve so that a portion of the refrigerant from the condenser flows to the return air port of the compressor through the main electronic expansion valve, the main heat exchange path and the evaporator in sequence;

[0017] Close the first auxiliary electronic expansion valve and open the second auxiliary electronic expansion valve, so that another part of the refrigerant from the condenser flows to the return air port of the compressor through the main electronic expansion valve, the second auxiliary electronic expansion valve and the second heat exchange auxiliary circuit in sequence.

[0018] According to some embodiments of the present application, the operating parameters of the air-conditioning system include the operating mode of the air-conditioning system, the startup time and exhaust temperature of the compressor, and the evaporation temperature of the evaporator; and determining that the air-conditioning system is in a low-load refrigeration condition according to the operating parameters includes:

[0019] When the operating parameters meet the preset entry conditions, it is determined that the air conditioning system is in a low-load cooling condition, wherein the preset entry conditions include:

[0020] When the operation mode is the cooling mode or the dehumidification mode, the startup time of the compressor reaches a first preset time;

[0021] The evaporation temperature of the evaporator is less than the difference between the target evaporation temperature and the first preset coefficient for a second preset time period;

[0022] The exhaust temperature of the compressor is greater than the second preset coefficient and less than the third preset coefficient for a third preset time period.

[0023] According to some embodiments of the present application, the method further includes:

[0024] Get the outdoor ambient temperature;

[0025] The initial opening degree of the second auxiliary electronic expansion valve is determined according to the outdoor ambient temperature.

[0026] According to some embodiments of the present application, the method further includes:

[0027] Obtaining the auxiliary circuit superheat of the second heat exchange auxiliary circuit;

[0028] Determining the adjustment increment opening of the second auxiliary circuit electronic expansion valve according to the auxiliary circuit superheat;

[0029] The real-time opening of the second auxiliary electronic expansion valve is adjusted based on the adjustment increment opening.

[0030] According to some embodiments of the present application, the method further includes:

[0031] When the operating parameters meet the preset exit conditions, it is determined that the air conditioning system is out of the low-load refrigeration condition, wherein the preset exit conditions include one of the following:

[0032] The operation mode is switched from a cooling mode or a dehumidification mode to another mode;

[0033] The compressor stops working;

[0034] The evaporation temperature of the evaporator is greater than the difference between the target evaporation temperature and the first preset coefficient for a second preset time period;

[0035] When the operation mode is the cooling mode or the dehumidification mode, the first auxiliary electronic expansion valve is opened.

[0036] In a third aspect, an embodiment of the present application provides a controller comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the control method of the air-conditioning system of the second aspect mentioned above when running the computer program.

[0037] In a fourth aspect, an embodiment of the present application provides an air-conditioning system, comprising the controller of the third aspect mentioned above.

[0038] In a fifth aspect, an embodiment of the present application provides a computer-readable storage medium storing computer-executable instructions, wherein the computer-executable instructions are used to execute the control method of the air-conditioning system as described in the second aspect above.

[0039] In the sixth aspect, an embodiment of the present application provides a computer program product, including a computer program or a computer instruction, characterized in that the computer program or the computer instruction is stored in a computer-readable storage medium, a processor of a computer device reads the computer program or the computer instruction from the computer-readable storage medium, and the processor executes the computer program or the computer instruction, so that the computer device executes the control method of the air-conditioning system as described in the second aspect above.

[0040] According to the technical solution of the embodiment of the present application, at least the following beneficial effects are achieved: the air-conditioning system of the embodiment of the present application adopts a two-stage spray enthalpy control of the plate heat exchanger, the first-stage spray enthalpy is sprayed into the medium-pressure chamber of the compressor, and the second-stage spray enthalpy is sprayed into the return air port of the compressor. Under low-load refrigeration conditions, the air-conditioning system of the embodiment of the present application can turn off the first-stage spray enthalpy and turn on the second-stage spray enthalpy, while still maintaining the supercooling of the first-stage spray enthalpy to ensure capacity and noise reduction; while meeting energy requirements, the circulation amount of refrigerant in the main circuit is reduced at the same time, thereby reducing power and current, and achieving energy-saving and power-saving effects.

[0041] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings are used to provide further understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application and do not constitute a limitation on the technical solution of the present application.

[0043] Figure 1 is a structural schematic diagram of an air conditioning system provided by an embodiment of the present application;

[0044] Figure 2This is a schematic diagram of flow exchange of a plate heat exchanger in an air conditioning system provided by an embodiment of the present application;

[0045] Figure 3 is a flow chart of a control method of an air conditioning system provided by an embodiment of the present application;

[0046] Figure 4 is a flow chart of a control method of an air conditioning system provided by another embodiment of the present application;

[0047] Figure 5 is a flow chart of a control method of an air conditioning system provided by another embodiment of the present application;

[0048] Figure 6 It is a schematic diagram of a controller for executing a control method of an air-conditioning system provided in one embodiment of the present application. DETAILED DESCRIPTION

[0049] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0050] In the description of the present application, it should be understood that descriptions involving orientation, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0051] In the description of this application, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed", etc. are understood to exclude the number itself, and "above", "below", "within", etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0052] In the description of this application, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in this application based on the specific content of the technical solution.

[0053] In some cases, some air conditioning heat pump units use injection enthalpy control, which is mainly achieved by taking liquid refrigerant from the high-pressure side, and then injecting it into the medium-pressure chamber of the compressor after throttling by the electronic expansion valve and heat exchange by the plate heat exchanger. The injection enthalpy system can be used to increase the system subcooling and air supply volume, thereby improving capacity.

[0054] However, for the traditional jet enthalpy increase system, under low load conditions (when the compressor frequency is low), the circulation volume of the refrigerant will be greatly reduced. Although the supercooling degree is increased, the mass flow rate is reduced. At this time, the capacity of the jet enthalpy increase system is very limited, but the system power is increased a lot, resulting in a large current and increased heat generation of the main control board. Under high-temperature extreme refrigeration conditions, it neither saves electricity nor reduces the reliability and life of the main control board due to the large heat generation.

[0055] In addition, under high temperature and low load conditions, if the spray enthalpy system is turned off, the system subcooling will be reduced, which may easily cause the refrigerant to be in a gas-liquid two-phase state when entering the indoor unit's electronic expansion valve, and the indoor unit system may have a loud refrigerant flushing sound.

[0056] Based on the above situation, the embodiment of the present application proposes a control method, controller, air conditioning system and medium for an air-conditioning system, which ensures the cooling capacity and noise reduction under low load conditions, and reduces power and current to achieve energy saving and power saving effects.

[0057] Various embodiments of the air conditioning system of the present application are further described below in conjunction with the accompanying drawings.

[0058] like Figure 1 to Figure 2 As shown, Figure 1 is a structural schematic diagram of an air conditioning system provided by an embodiment of the present application; Figure 2 It is a schematic diagram of flow exchange of a plate heat exchanger 400 in an air-conditioning system provided in one embodiment of the present application.

[0059] In one embodiment, the air conditioning system includes but is not limited to an evaporator, a condenser 200, a compressor 100, a plate heat exchanger 400, a main electronic expansion valve 300, a first auxiliary electronic expansion valve 511 and a second auxiliary electronic expansion valve 521, wherein the plate heat exchanger 400 is provided with a main heat exchange circuit, a first auxiliary heat exchange circuit and a second auxiliary heat exchange circuit, one end of the condenser 200 is connected to the exhaust port of the compressor 100, and the other end is connected to the evaporator through the main electronic expansion valve 300 and the heat exchange main circuit, one end of the main electronic expansion valve 300 close to the heat exchange main circuit is connected to the enthalpy increase port of the compressor 100 through the first auxiliary electronic expansion valve 511 and the first heat exchange auxiliary circuit, and is also connected to the return air port of the compressor 100 through the second auxiliary electronic expansion valve 521 and the second heat exchange auxiliary circuit.

[0060] Among them, the plate heat exchanger 400 is a device for heat transfer, usually used for heating, cooling or evaporating fluid. It consists of a series of flat plates with certain gaps between them, and the fluid flows in these gaps to achieve the purpose of heat transfer. The advantages of the plate heat exchanger 400 include high heat transfer efficiency, small space occupation, and easy maintenance.

[0061] It should be noted that, under low-load refrigeration conditions, the main electronic expansion valve 300 and the second auxiliary electronic expansion valve 521 are both in an open state, and the first auxiliary electronic expansion valve 511 is in a closed state.

[0062] That is, in the cooling mode and when the load is low, the refrigerant will be discharged from the exhaust port of the compressor 100 and enter the condenser 200 for condensation. The condensed refrigerant will pass through the main electronic expansion valve 300. Then, a part of the refrigerant passing through the main electronic expansion valve 300 will enter the evaporator through the main heat exchange path of the plate heat exchanger 400 for evaporation. The refrigerant that has been evaporated will flow back to the return air port of the compressor 100. In addition, another part of the refrigerant passing through the main electronic expansion valve 300 will enter the second heat exchange auxiliary path of the heat exchanger through the second auxiliary electronic expansion valve 521, exchange heat with the refrigerant in the heat exchange main path, and then the refrigerant passing through the second heat exchange auxiliary path will flow to the return air port of the compressor 100.

[0063] It is worth noting that the air-conditioning system of the embodiment of the present application adopts a two-stage spray enthalpy control of the plate heat exchanger 400, the first-stage spray enthalpy is sprayed into the medium-pressure chamber of the compressor 100, and the second-stage spray enthalpy is sprayed into the return air port of the compressor 100. Under low-load refrigeration conditions, the air-conditioning system of the embodiment of the present application can turn off the first-stage spray enthalpy and turn on the second-stage spray enthalpy, while still maintaining the supercooling of the first-stage spray enthalpy to ensure capacity and noise reduction; while meeting energy requirements, the circulation amount of refrigerant in the main line is reduced at the same time, thereby reducing power and current, and achieving energy-saving and power-saving effects.

[0064] In one embodiment, the air-conditioning system also includes a first auxiliary capillary 512 and a second auxiliary capillary 522. The first auxiliary capillary 512 is arranged on the side of the first auxiliary circuit electronic expansion valve 511 away from the first heat exchange auxiliary circuit, and the second auxiliary capillary 522 is arranged on the side of the second auxiliary circuit electronic expansion valve 521 away from the second heat exchange auxiliary circuit.

[0065] Specifically, the first auxiliary capillary tube 512 has a smaller inner diameter, and can allow the refrigerant to flow smoothly to the first heat exchange auxiliary path through capillary action. Similarly, the second auxiliary capillary tube 522 can also allow the refrigerant to flow smoothly to the second heat exchange auxiliary path through capillary action.

[0066] In one embodiment, the air-conditioning system also includes a gas-liquid separator 600. In the cooling mode or the dehumidification mode, the gas phase input port of the gas-liquid separator 600 is connected to the evaporator and the second heat exchange auxiliary circuit, and the liquid phase output port of the gas-liquid separator 600 is connected to the return air port of the compressor 100.

[0067] Specifically, the gas-liquid separator 600 is an important component, which is mainly used to separate gas and liquid in the refrigerant to ensure that only gaseous refrigerant enters the compressor 100, thereby protecting the compressor 100 from damage such as liquid hammer.

[0068] In one embodiment, the air conditioning system also includes an oil separator 700, the input port of the oil separator 700 is connected to the exhaust port of the compressor 100, the oil output port of the oil separator 700 is connected to the return air port of the compressor 100, and the refrigerant output port of the oil separator 700 is connected to the condenser 200.

[0069] Specifically, the main function of the oil separator 700 is to separate the lubricating oil from the refrigerant vapor discharged from the compressor 100. Due to the different densities of the lubricating oil and the refrigerant, the lubricating oil is separated from the gaseous refrigerant through the inertial separation, gravity sedimentation, centrifugal force and other effects of the oil separator 700. In addition, the separated lubricating oil returns to the compressor 100 through the oil return line at the bottom of the oil separator 700, ensuring that the compressor 100 has enough lubricating oil for lubrication and preventing the compressor 100 from being damaged due to lack of oil. At the same time, the amount of oil entering the subsequent equipment such as the condenser 200 is reduced to avoid affecting the heat exchange effect.

[0070] An oil return capillary may be provided in the oil return pipeline. Since the inner diameter of the oil return capillary is relatively small, the oil can smoothly flow back to the compressor 100 through capillary action.

[0071] In one embodiment, the air conditioning system further includes a four-way valve 800 , which is connected to the exhaust port and the return port of the evaporator, the condenser 200 , and the compressor 100 , respectively.

[0072] Based on the hardware structure of the air-conditioning system in each of the above-mentioned embodiments, various embodiments of the control method of the air-conditioning system of the present application are respectively proposed below.

[0073] like Figure 3 As shown, Figure 3 It is a flowchart of a control method of an air-conditioning system provided by an embodiment of the present application; the control method of the air-conditioning system may include but is not limited to step S310, step S320 and step S330.

[0074] Step S310, obtaining operating parameters of the air conditioning system;

[0075] Step S320: Determine that the air conditioning system is in a low-load refrigeration condition according to the operating parameters, and open the main electronic expansion valve to allow a portion of the refrigerant from the condenser to flow to the return air port of the compressor through the main electronic expansion valve, the heat exchange main circuit and the evaporator in sequence;

[0076] Step S330, close the first auxiliary electronic expansion valve, and open the second auxiliary electronic expansion valve, so that another part of the refrigerant from the condenser flows to the return air port of the compressor through the main electronic expansion valve, the second auxiliary electronic expansion valve and the second heat exchange auxiliary circuit in sequence.

[0077] In one embodiment, first, if it is determined according to the operating parameters of the air-conditioning system that the air-conditioning system is in a low-load refrigeration condition, the air-conditioning system will open the main electronic expansion valve and the second auxiliary electronic expansion valve, and close the first auxiliary electronic expansion valve, that is, open the first-level spray enthalpy and close the second-level spray enthalpy, so that a part of the refrigerant passing through the main electronic expansion valve will enter the evaporator through the main heat exchange path of the plate heat exchanger for evaporation treatment, and the refrigerant after evaporation treatment will flow back to the return air port of the compressor; in addition, another part of the refrigerant passing through the main electronic expansion valve will enter the second heat exchange auxiliary path of the heat exchanger through the second auxiliary electronic expansion valve, exchange heat with the refrigerant in the main heat exchange path, and then, the refrigerant passing through the second heat exchange auxiliary path will flow to the return air port of the compressor.

[0078] In one embodiment, the operating parameters of the air-conditioning system may include at least one of the following: an operating mode of the air-conditioning system, a start-up time and exhaust temperature of the compressor, and an evaporation temperature of the evaporator.

[0079] It should be noted that under low-load cooling conditions, the heat load of the room is relatively small, the compressor frequency is relatively low, and the air conditioner does not need to operate at its maximum cooling capacity. For example, low-load cooling conditions will occur at night or on cloudy days when the outside temperature is low, or when there are few people in the room and the equipment generates less heat.

[0080] It is worth noting that the air-conditioning system of the embodiment of the present application adopts a two-stage spray enthalpy control of the plate heat exchanger. The first-stage spray enthalpy is sprayed into the medium-pressure chamber of the compressor, and the second-stage spray enthalpy is sprayed into the return air port of the compressor. Under low-load refrigeration conditions, the air-conditioning system of the embodiment of the present application can turn off the first-stage spray enthalpy and turn on the second-stage spray enthalpy, while still maintaining the supercooling of the first-stage spray enthalpy to ensure capacity and noise reduction; while meeting energy requirements, the circulation volume of the refrigerant in the main line is reduced at the same time, thereby reducing power and current, achieving energy-saving and power-saving effects.

[0081] In one embodiment, regarding the above step S320 of determining that the air conditioning system is in a low-load cooling condition according to the operating parameters, the following conditions may be met to determine that the air conditioning system is in a low-load cooling condition:

[0082] The first condition: when the operating mode is cooling mode or dehumidification mode, the startup time of the compressor reaches a first preset time; wherein, the startup time of the compressor reaches the first preset time to ensure that the air-conditioning system has entered a stable operation stage.

[0083] The second condition: the evaporating temperature of the evaporator continues to be less than the difference between the target evaporating temperature and the first preset coefficient for a second preset time period; if the second condition is met, it can be said that the heat load is reduced, that is, when the heat load of the space served by the air conditioner is reduced, such as the number of people in the room decreases, the heat generation of the equipment decreases, or the outdoor temperature drops, if the air-conditioning system fails to adjust the operating status in time and still operates according to the original operating mode, it will cause the evaporating temperature to be lower than the target value.

[0084] The third condition: the exhaust temperature of the compressor is greater than the second preset coefficient and less than the third preset coefficient for a third preset time period; if the second condition is met, the compressor can operate normally and the heat load is reduced. When the heat load is reduced, the cooling capacity required by the system is reduced, and the load of the compressor will also be reduced accordingly, resulting in a decrease in the exhaust temperature. For example, at night or on cloudy days when the outside temperature is low, or when there are fewer people in the room and the equipment generates less heat, the heat load of the air conditioner will decrease, and the exhaust temperature of the compressor may be lower than the third preset coefficient.

[0085] In addition, if Figure 4 As shown, Figure 4 It is a flowchart of a control method of an air-conditioning system provided by another embodiment of the present application; the control method of the air-conditioning system may include but is not limited to step S410 and step S420.

[0086] Step S410, obtaining the outdoor ambient temperature;

[0087] Step S420: Determine the initial opening of the second auxiliary electronic expansion valve according to the outdoor ambient temperature.

[0088] In one embodiment, the embodiment of the present application will also determine the initial opening of the second auxiliary electronic expansion valve according to the outdoor ambient temperature. For example, if the outdoor ambient temperature is higher, then a stronger cooling capacity is required. In this regard, the initial opening of the second auxiliary electronic expansion valve can be appropriately increased, and the high-temperature cooling capacity of the air-conditioning system can be improved by increasing the enthalpy increase capacity of the secondary enthalpy increase.

[0089] In addition, if Figure 5 As shown, Figure 5 It is a flowchart of a control method of an air-conditioning system provided by another embodiment of the present application; the control method of the air-conditioning system may include but is not limited to step S510, step S520 and step S530.

[0090] Step S510, obtaining the auxiliary circuit superheat of the second heat exchange auxiliary circuit;

[0091] Step S520, determining the adjustment increment opening of the second auxiliary circuit electronic expansion valve according to the auxiliary circuit superheat;

[0092] Step S530: adjusting the real-time opening of the second auxiliary electronic expansion valve based on the adjusted incremental opening.

[0093] In one embodiment, the embodiment of the present application will also determine the adjustment increment opening of the second auxiliary circuit electronic expansion valve according to the auxiliary circuit superheat of the second heat exchange auxiliary circuit, so as to adjust the real-time opening of the second auxiliary circuit electronic expansion valve. For example, if the auxiliary circuit superheat is high, the refrigerant outlet temperature of the second heat exchange auxiliary circuit is much higher than the refrigerant inlet temperature, indicating that the heat exchange effect of the refrigerant in the second heat exchange auxiliary circuit is strong, and also indicating that the refrigerant flow rate flowing through the second heat exchange auxiliary circuit is small. In this regard, the embodiment of the present application can appropriately increase the real-time opening of the second auxiliary circuit electronic expansion valve; in addition, if the auxiliary circuit superheat is low, the refrigerant outlet temperature of the second heat exchange auxiliary circuit is not much higher than the refrigerant inlet temperature, indicating that the heat exchange effect of the refrigerant in the second heat exchange auxiliary circuit is general, and also indicating that the refrigerant flow rate flowing through the second heat exchange auxiliary circuit is large. In this regard, the embodiment of the present application can appropriately reduce the real-time opening of the second auxiliary circuit electronic expansion valve.

[0094] In one embodiment, at least one of the following conditions may need to be met to determine that the air-conditioning system has left the low-load refrigeration condition: 1. The operating mode is switched from the refrigeration mode or the dehumidification mode to other modes; 2. The compressor stops working; 3. The evaporation temperature of the evaporator continues to be greater than the difference between the target evaporation temperature and the first preset coefficient for a second preset time period; 4. When the operating mode is the refrigeration mode or the dehumidification mode, the first auxiliary electronic expansion valve is opened.

[0095] Based on the control methods of the air-conditioning system of the above-mentioned various embodiments, overall embodiments of the control methods of the air-conditioning system of the present application are respectively proposed below.

[0096] In one embodiment, the system principle of the embodiment of the present application is: Figure 1 and Figure 2 As shown, the system adopts two-stage enthalpy spray control of integrated plate heat exchanger, the first stage enthalpy spray is sprayed into the compressor medium pressure cavity, and the second stage enthalpy spray is sprayed into the gas liquid separator.

[0097] In addition, the control idea of ​​the embodiment of the present application is: under low load (compressor running at low frequency), turn off the first-stage spray enthalpy, that is, the first auxiliary electronic expansion valve, and turn on the second-stage spray enthalpy control, turn on the second-stage spray enthalpy, that is, the second auxiliary electronic expansion valve, and still maintain the supercooling of the first-stage spray enthalpy to ensure capacity and noise reduction; while meeting energy requirements, reduce the circulation volume of the refrigerant in the main circuit at the same time, so as to reduce power and current and achieve energy saving and power saving effects.

[0098] In addition, the control logic of the embodiment of the present application is as follows:

[0099] To enter, you must meet the following conditions:

[0100] ① In cooling or dehumidification mode, the compressor starts t1 minute later;

[0101] ②T 2max <T arget –K, and last for 1 minute;

[0102] ③M<TP<N℃ for 5 seconds;

[0103] Wherein, t1 represents the compression start time, and the value range can be 1 to 60; T 2max represents the evaporation temperature of the indoor unit. If there are multiple indoor units, then T 2max Characterizes the maximum evaporation temperature of all indoor units; T arget It represents the target evaporation temperature of the indoor unit system; K is a coefficient, and its value range is -255 to 255; M and N are coefficients, and their value range is 0 to 120; TP represents the exhaust temperature.

[0104] Execute action:

[0105] 1. Turn off the first auxiliary circuit electronic expansion valve and turn on the second auxiliary circuit electronic expansion valve;

[0106] 2. The control of the second auxiliary circuit electronic expansion valve is as follows:

[0107] (1) The initial opening control of the second auxiliary electronic expansion valve is shown in Table 1:

[0108]

[0109] Table 1

[0110] Among them, the initial opening degree of the second auxiliary electronic expansion valve has different initial opening degrees according to different outdoor ambient temperatures T4; a, b, c, d, k1, k2, k3, and k4 are constant values.

[0111] (2) The opening degree of the second auxiliary electronic expansion valve is controlled by superheat as shown in Table 2:

[0112]

[0113]

[0114] Table 2

[0115] In addition, the parameter definitions are shown in Table 3 below:

[0116]

[0117] Table 3

[0118] wherein, T CSH can only be a positive number. If T7B < T7A, then T CSH is calculated as 0.

[0119] Exit conditions (meeting any of the following conditions):

[0120] ① The cooling / dehumidification mode changes to other modes, or the compressor stops

[0121] ② T 2max > T arget – K and lasts for 1 minute;

[0122] ③ In the cooling / dehumidification mode, the first-stage injection enthalpy is turned on.

[0123] Based on the control methods of the air-conditioning systems in the above various embodiments, during the operation of the cooling mode, the secondary injection enthalpy control of the dual-stage injection enthalpy control system is flexibly used, which ensures the capacity output while achieving the effects of energy saving and noise reduction under low-load demands.

[0124] Based on the control methods of the air-conditioning systems in the above various embodiments, the following respectively present the various embodiments of the controller, the air-conditioning system, the computer-readable storage medium, and the computer program product of the present application.

[0125] As Figure 6 shown, Figure 6 is a schematic diagram of a controller for executing the control method of the air-conditioning system provided by an embodiment of the present application. The controller 900 implemented in the present application includes: a processor 910, a memory 920, and a computer program stored on the memory 920 and executable on the processor 910. Among them, Figure 6 one processor 910 and one memory 920 are taken as an example.

[0126] The processor 910 and the memory 920 can be connected through a bus or other means, Figure 6 and taking the connection through a bus as an example.

[0127] The memory 920, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer executable programs. In addition, the memory 920 may include a high-speed random access memory, and may also include a non-transitory memory, such as at least one disk storage device, a flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory 920 may optionally include a memory 920 remotely arranged relative to the processor 910, and these remote memories 920 may be connected to the controller 900 via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0128] Those skilled in the art will understand that Figure 6 The device structure shown in the figure does not constitute a limitation on the controller 900, and may include more or less components than shown in the figure, or combine certain components, or arrange the components differently.

[0129] exist Figure 6 In the controller 900 shown, the processor 910 can be used to call the control program stored in the memory 920, so as to implement the control method of the air-conditioning system described above. Specifically, the non-transient software program and instructions required to implement the control method of the air-conditioning system of the above embodiment are stored in the memory 920, and when executed by the processor 910, the control method of the air-conditioning system of the above embodiment is executed.

[0130] It is worth noting that since the controller 900 of the embodiment of the present application can execute the control method of the air-conditioning system of any of the above-mentioned embodiments, the specific implementation manner and technical effects of the controller 900 of the embodiment of the present application can refer to the specific implementation manner and technical effects of the control method of the air-conditioning system of any of the above-mentioned embodiments.

[0131] In addition, an embodiment of the present application further provides an air conditioning system, which includes the controller of the above embodiment.

[0132] It is worth noting that since the air-conditioning system of the embodiment of the present application includes the controller of the above-mentioned embodiment, and the controller of the above-mentioned embodiment can execute the control method of the air-conditioning system of any of the above-mentioned embodiments, the specific implementation methods and technical effects of the air-conditioning system of the embodiment of the present application can refer to the specific implementation methods and technical effects of the control method of the air-conditioning system of any of the above-mentioned embodiments.

[0133] In addition, an embodiment of the present application further provides a computer-readable storage medium, which stores computer-executable instructions, and the computer-executable instructions are used to execute the control method of the air-conditioning system described above. Figures 3 to 5 The method steps in .

[0134] It is worth noting that since the computer-readable storage medium of the embodiment of the present application can execute the control method of the air-conditioning system of any of the above-mentioned embodiments, the specific implementation methods and technical effects of the computer-readable storage medium of the embodiment of the present application can refer to the specific implementation methods and technical effects of the control method of the air-conditioning system of any of the above-mentioned embodiments.

[0135] In addition, an embodiment of the present application further provides a computer program product, including a computer program or a computer instruction, the computer program or the computer instruction is stored in a computer-readable storage medium, the processor of the computer device reads the computer program or the computer instruction from the computer-readable storage medium, and the processor executes the computer program or the computer instruction, so that the computer device executes the control method of the air-conditioning system described above. Figures 3 to 5 The method steps in .

[0136] It is worth noting that since the computer program product of the embodiment of the present application can execute the control method of the air-conditioning system of any of the above-mentioned embodiments, the specific implementation methods and technical effects of the computer program product of the embodiment of the present application can refer to the specific implementation methods and technical effects of the control method of the air-conditioning system of any of the above-mentioned embodiments.

[0137] It will be appreciated by those skilled in the art that all or some of the steps and systems in the disclosed method above may be implemented as software, firmware, hardware and appropriate combinations thereof. Some physical components or all physical components may be implemented as software executed by a processor, such as a central processing unit, a digital signal processor or a microprocessor, or may be implemented as hardware, or may be implemented as an integrated circuit, such as an application specific integrated circuit. Such software may be distributed on a computer-readable medium, which may include a computer storage medium (or a non-transitory medium) and a communication medium (or a temporary medium). As known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tapes, disk storage or other magnetic storage devices, or any other medium that may be used to store desired information and may be accessed by a computer. Furthermore, it is well known to those skilled in the art that communication media typically include computer readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0138] It should be understood that in the present application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0139] In several embodiments provided in the present application, it should be understood that the disclosed systems, apparatuses and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely schematic, for example, the division of units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of apparatuses or units, which can be electrical, mechanical or other forms. The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the scheme of this embodiment.

[0140] It should also be understood that the various implementations provided in the embodiments of the present application can be combined arbitrarily to achieve different technical effects.

[0141] The above is a specific description of the preferred implementation of the present application, but the present application is not limited to the above implementation mode. Technical personnel familiar with the field can also make various equivalent modifications or substitutions under the shared conditions without violating the spirit of the present application. These equivalent modifications or substitutions are all included in the scope defined by the claims of the present application.

Claims

1. An air conditioning system, characterized in that: include: Evaporators, condensers and compressors; A plate heat exchanger, a main electronic expansion valve, a first auxiliary electronic expansion valve and a second auxiliary electronic expansion valve, wherein the plate heat exchanger is provided with a main heat exchange path, a first auxiliary heat exchange path and a second auxiliary heat exchange path, one end of the condenser is connected to the exhaust port of the compressor, and the other end is connected to the evaporator through the main electronic expansion valve and the main heat exchange path, one end of the main electronic expansion valve close to the main heat exchange path is connected to the enthalpy increase port of the compressor through the first auxiliary electronic expansion valve and the first heat exchange auxiliary path, and is also connected to the return air port of the compressor through the second auxiliary electronic expansion valve and the second heat exchange auxiliary path; Wherein, under low-load refrigeration conditions, the main electronic expansion valve and the second auxiliary electronic expansion valve are both in an open state, and the first auxiliary electronic expansion valve is in a closed state.

2. The air conditioning system according to claim 1, characterized in that: The air conditioning system also includes a first auxiliary capillary and a second auxiliary capillary. The first auxiliary capillary is arranged on a side of the first auxiliary circuit electronic expansion valve away from the first heat exchange auxiliary circuit, and the second auxiliary capillary is arranged on a side of the second auxiliary circuit electronic expansion valve away from the second heat exchange auxiliary circuit.

3. The air conditioning system according to claim 1, characterized in that: The air conditioning system also includes a gas-liquid separator. In a cooling mode or a dehumidification mode, the gas phase input port of the gas-liquid separator is connected to the evaporator and the second heat exchange auxiliary circuit, and the liquid phase output port of the gas-liquid separator is connected to the return air port of the compressor.

4. The air conditioning system according to claim 1, characterized in that: The air conditioning system also includes an oil separator, the input port of the oil separator is connected to the exhaust port of the compressor, the oil output port of the oil separator is connected to the return air port of the compressor, and the refrigerant output port of the oil separator is connected to the condenser.

5. The air conditioning system according to claim 1, characterized in that: The air conditioning system further comprises a four-way valve, which is respectively connected to the exhaust port and the return port of the evaporator, the condenser, and the compressor.

6. A control method for an air conditioning system, characterized in that: Applicable to the air conditioning system according to any one of claims 1 to 5; the method comprises: Obtaining operating parameters of the air conditioning system; Determining that the air conditioning system is in a low-load refrigeration condition according to the operating parameters, opening the main electronic expansion valve so that a portion of the refrigerant from the condenser flows to the return air port of the compressor through the main electronic expansion valve, the main heat exchange path and the evaporator in sequence; Close the first auxiliary electronic expansion valve and open the second auxiliary electronic expansion valve, so that another part of the refrigerant from the condenser flows to the return air port of the compressor through the main electronic expansion valve, the second auxiliary electronic expansion valve and the second heat exchange auxiliary circuit in sequence.

7. The method according to claim 6, characterized in that The operating parameters of the air-conditioning system include the operating mode of the air-conditioning system, the startup time and exhaust temperature of the compressor, and the evaporation temperature of the evaporator; and determining that the air-conditioning system is in a low-load refrigeration condition according to the operating parameters includes: When the operating parameters meet the preset entry conditions, it is determined that the air conditioning system is in a low-load cooling condition, wherein the preset entry conditions include: When the operation mode is the cooling mode or the dehumidification mode, the startup time of the compressor reaches a first preset time; The evaporation temperature of the evaporator is less than the difference between the target evaporation temperature and the first preset coefficient for a second preset time period; The exhaust temperature of the compressor is greater than the second preset coefficient and less than the third preset coefficient for a third preset time period.

8. The method according to claim 6, characterized in that The method further comprises: Get the outdoor ambient temperature; The initial opening degree of the second auxiliary electronic expansion valve is determined according to the outdoor ambient temperature.

9. The method according to claim 6, characterized in that The method further comprises: Obtaining the auxiliary circuit superheat of the second heat exchange auxiliary circuit; Determining the adjustment increment opening of the second auxiliary circuit electronic expansion valve according to the auxiliary circuit superheat; The real-time opening of the second auxiliary electronic expansion valve is adjusted based on the adjustment increment opening.

10. The method according to claim 7, characterized in that The method further comprises: When the operating parameters meet the preset exit condition, it is determined that the air conditioning system is out of the low-load refrigeration condition, wherein the preset exit condition includes one of the following: The operation mode is switched from a cooling mode or a dehumidification mode to another mode; The compressor stops working; The evaporation temperature of the evaporator is greater than the difference between the target evaporation temperature and the first preset coefficient for a second preset time period; When the operation mode is the cooling mode or the dehumidification mode, the first auxiliary electronic expansion valve is opened.

11. A controller, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the control method for the air conditioning system according to any one of claims 6 to 10 when executing the computer program.

12. An air conditioning system, characterized in that: Comprising a controller as claimed in claim 11.

13. A computer-readable storage medium, characterized in that: Computer executable instructions are stored, and the computer executable instructions are used to execute the control method of the air-conditioning system according to any one of claims 6 to 10.

14. A computer program product comprising a computer program or computer instructions, characterized in that The computer program or the computer instructions are stored in a computer-readable storage medium, the processor of a computer device reads the computer program or the computer instructions from the computer-readable storage medium, and the processor executes the computer program or the computer instructions, so that the computer device executes the control method of the air-conditioning system as described in any one of claims 6 to 10.

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