Air conditioner and refrigerant regulating method thereof

Abstract

The present invention discloses an air conditioner and a refrigerant regulating method for the air conditioner, an air conditioner refrigeration system, a refrigerant regulating device and a pressure sensing device, wherein the refrigerant regulating device includes a gas-liquid storage device, a first control valve and a second control valve. During the operation of the air conditioner, the flow rate of the refrigerant in the refrigeration system is detected; according to the flow rate of the refrigerant and the pressure value collected by the pressure sensing device, the opening of the throttling device in the refrigeration system and the on-off state of the first control valve and the second control valve are controlled to adjust the flow rate of the refrigerant in the refrigeration system. By adopting the technical means of the present invention, it is possible to adjust the flow rate of the refrigerant in the refrigeration system according to different actual loads during the operation of the air conditioner, taking into account the requirements of energy saving and low consumption while ensuring the output capacity, thereby improving the user experience.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigerant regulation, and in particular to an air conditioner and a refrigerant regulation method for the air conditioner. Background Art

[0002] As people's living standards continue to improve, air conditioners have become a necessity in daily life. When developing existing air conditioning units, a fixed refrigerant charge is determined based on local performance requirements and the reliability of the air conditioning system. The refrigerant is added to the unit during production. Therefore, during the operation of the air conditioner, the refrigerant amount of the refrigeration system is fixed and cannot be adjusted.

[0003] However, the inventors found that the prior art has at least the following problems: the intelligent development of air conditioners has led to higher and higher requirements for air conditioners. When the air conditioner operates under different loads, the required output capacity is different. Under high load, the maximum output capacity is required to ensure the cooling or heating effect of the air conditioner; while under medium and low loads, the low energy consumption and energy saving requirements are pursued under a certain output capacity. However, since the amount of refrigerant in the existing refrigeration system is fixed, if it is filled too little, it may lead to insufficient output capacity under high load conditions. If it is filled too much, there will be a large energy consumption under medium and low load conditions, making it difficult to provide users with a good user experience. Summary of the invention

[0004] The purpose of the embodiments of the present invention is to provide an air conditioner and a refrigerant regulation method for the air conditioner, which can adjust the flow rate of the refrigerant in the refrigeration system according to different actual loads during the operation of the air conditioner, while ensuring the output capacity and taking into account the needs of energy saving and low consumption, thereby improving the user experience.

[0005] To achieve the above object, an embodiment of the present invention provides an air conditioner, comprising:

[0006] Refrigeration systems, including compressors and throttling devices;

[0007] A refrigerant regulating device, comprising a gas-liquid storage device, a first control valve and a second control valve; wherein the first end of the gas-liquid storage device is connected to the pipeline on the high-pressure side of the compressor through the first control valve; the second end of the gas-liquid storage device is connected to the pipeline on the low-pressure side of the compressor through the second control valve;

[0008] a pressure sensing device, comprising a first pressure sensor disposed on the high-pressure side, a second pressure sensor disposed on the low-pressure side, and a third pressure sensor disposed between the first control valve and the second control valve;

[0009] Controller for:

[0010] During the operation of the air conditioner, detecting the flow rate of the refrigerant in the refrigeration system;

[0011] According to the flow rate of the refrigerant and the pressure value collected by the pressure sensor device, the opening degree of the throttling device and the on-off state of the first control valve and the second control valve are controlled to adjust the flow rate of the refrigerant in the refrigeration system.

[0012] As an improvement of the above solution, the detection of the flow rate of the refrigerant in the refrigeration system is specifically as follows:

[0013] Detecting the flow level of the refrigerant in the refrigeration system; wherein the flow level is excessive flow, insufficient flow or moderate flow.

[0014] As an improvement of the above solution, the pressure values ​​collected by the pressure sensing device include: a pressure value of the high-pressure side of the compressor collected by the first pressure sensor as the first pressure value, a pressure value of the low-pressure side of the compressor collected by the second pressure sensor as the second pressure value, and a pressure value of the gas-liquid storage device collected by the third pressure sensor as the third pressure value;

[0015] The controlling the opening of the throttling device and the on-off state of the first control valve and the second control valve according to the flow rate of the refrigerant and the pressure value collected by the pressure sensor device to adjust the flow rate of the refrigerant in the refrigeration system specifically includes:

[0016] When it is determined that the flow rate of the refrigerant is excessive, determining whether the first pressure value is greater than or equal to the sum of the third pressure value and a first pressure difference threshold;

[0017] If yes, control the first control valve to be turned on until the first pressure value is less than or equal to the sum of the third pressure value and the second pressure difference threshold, or when the first pressure value is less than or equal to the upper limit of a preset pressure value range, control the first control valve to be turned off;

[0018] If not, reduce the opening of the throttling device until the first pressure value is greater than or equal to the sum of the third pressure value and the first pressure difference threshold, and execute: control the first control valve to be turned on until the first pressure value is less than or equal to the sum of the third pressure value and the second pressure difference threshold, or when the first pressure value is less than or equal to the upper limit of a preset pressure value range, control the first control valve to be turned off;

[0019] The first pressure difference threshold is greater than the second pressure difference threshold.

[0020] As an improvement of the above scheme, the opening of the throttling device and the on-off state of the first control valve and the second control valve are controlled according to the flow rate of the refrigerant and the pressure value collected by the pressure sensor device to adjust the flow rate of the refrigerant in the refrigeration system, and further includes:

[0021] When it is determined that the flow rate of the refrigerant is too small, determining whether the third pressure value is greater than the sum of the second pressure value and a third pressure difference threshold;

[0022] If yes, control the second control valve to be turned on until the third pressure value is less than or equal to the sum of the second pressure value and the fourth pressure difference threshold, or when the second pressure value is greater than or equal to the lower limit of the preset pressure value range, control the second control valve to be turned off;

[0023] If not, reduce the opening of the throttling device until the third pressure value is greater than the sum of the second pressure value and the third pressure difference threshold, and execute: control the second control valve to be turned on until the third pressure value is less than or equal to the sum of the second pressure value and the fourth pressure difference threshold, or when the second pressure value is greater than or equal to the lower limit of the preset pressure value range, control the second control valve to be turned off.

[0024] The third pressure difference threshold is greater than the fourth pressure difference threshold.

[0025] As an improvement of the above solution, the refrigerant regulating device further includes a heating device, and the heating device is arranged on the surface of the gas-liquid storage device;

[0026] When it is determined that the flow rate of the refrigerant is too small, if the third pressure value is not greater than the sum of the second pressure value and the third pressure difference threshold, the controller is further configured to:

[0027] The heating device is controlled to start running until the third pressure value is greater than the sum of the second pressure value and a third pressure difference threshold, and then the heating device is controlled to stop running.

[0028] As an improvement of the above scheme, the opening of the throttling device and the on-off state of the first control valve and the second control valve are controlled according to the flow rate of the refrigerant and the pressure value collected by the pressure sensor device to adjust the flow rate of the refrigerant in the refrigeration system, and further includes:

[0029] When it is determined that the flow rate of the refrigerant is moderate, the opening degree of the throttling device and the on-off state of the first control valve and the second control valve are maintained unchanged.

[0030] As an improvement of the above solution, the detecting the flow level of the refrigerant in the refrigeration system specifically includes:

[0031] Detecting a pressure value at an exhaust port of the compressor as an exhaust pressure value;

[0032] The flow level of the refrigerant in the refrigeration system is determined according to the exhaust pressure value.

[0033] As an improvement of the above solution, judging the flow level of the refrigerant in the refrigeration system according to the exhaust pressure value specifically includes:

[0034] When the exhaust pressure value is greater than a first exhaust pressure threshold, it is determined that the flow rate of the refrigerant in the refrigeration system is excessive;

[0035] When the exhaust pressure value is less than a second exhaust pressure threshold, it is determined that the flow rate of the refrigerant in the refrigeration system is too small;

[0036] When the exhaust pressure value is less than or equal to the first exhaust pressure threshold and greater than or equal to the second exhaust pressure threshold, it is determined that the flow rate of the refrigerant in the refrigeration system is moderate;

[0037] Wherein, the first exhaust pressure threshold is greater than the second exhaust pressure threshold.

[0038] As an improvement of the above solution, the first exhaust pressure threshold is the sum of a preset ideal exhaust pressure value and a fifth pressure difference threshold; the second exhaust pressure threshold is the difference between a preset ideal exhaust pressure value and a sixth pressure difference threshold;

[0039] The ideal exhaust pressure value, the fifth pressure difference threshold, and the sixth pressure difference threshold are determined according to the current ambient temperature and the operating frequency of the compressor.

[0040] The embodiment of the present invention further provides a refrigerant adjustment method for an air conditioner, the air conditioner comprising:

[0041] Refrigeration systems, including compressors and throttling devices;

[0042] A refrigerant regulating device, comprising a gas-liquid storage device, a first control valve and a second control valve; wherein the first end of the gas-liquid storage device is connected to the pipeline on the high-pressure side of the compressor through the first control valve; the second end of the gas-liquid storage device is connected to the pipeline on the low-pressure side of the compressor through the second control valve;

[0043] a pressure sensing device, comprising a first pressure sensor disposed on the high-pressure side, a second pressure sensor disposed on the low-pressure side, and a third pressure sensor disposed between the first control valve and the second control valve;

[0044] The method comprises:

[0045] During the operation of the air conditioner, detecting the flow rate of the refrigerant in the refrigeration system;

[0046] According to the flow rate of the refrigerant and the pressure value collected by the pressure sensor device, the opening degree of the throttling device and the on-off state of the first control valve and the second control valve are controlled to adjust the flow rate of the refrigerant in the refrigeration system.

[0047] Compared with the prior art, the present invention discloses an air conditioner and a refrigerant regulating method for the air conditioner. A refrigerant regulating device is connected to the refrigeration system of the air conditioner to realize the storage and release of the refrigerant, and a pressure sensing device is set to detect the pressure values ​​at different positions in the system. During the operation of the air conditioner, the flow rate of the refrigerant in the refrigeration system is judged in real time; and according to the flow rate of the refrigerant and the pressure values ​​at different positions, the opening degree of the throttling device in the refrigeration system and the on-off state of the refrigerant regulating device are controlled, so that during the operation of the air conditioner, the flow rate of the refrigerant in the refrigeration system can be adjusted according to different actual load conditions and the actual size of the refrigerant, so that the flow rate of the refrigerant in the refrigeration system is maintained at an appropriate value. Under high load conditions, the refrigerant in the gas-liquid storage device is released to increase the refrigerant amount of the refrigeration system, improve the unit transportation capacity of energy, achieve higher capacity output of the air conditioner, and improve comfort. Under medium and low loads, if the amount of refrigerant in the refrigeration system is too much, the work of the unit will increase and the energy consumption will increase. Therefore, by storing the excess refrigerant, both the appropriate capacity output and the power consumption can be met, and the liquid hammer problem caused by excessive refrigerant can be avoided. Under low-temperature heating conditions, the pressure on the low-pressure side of the system can also be increased by adding an appropriate amount of refrigerant, so that the low-pressure side heat exchanger is not easy to frost, thereby increasing its heating capacity. In addition, since the refrigerant flow rate of the refrigeration system in the embodiment of the present invention is adjustable, when the air conditioner needs to use a long connecting pipe, there is no need to increase the cooling or heating efficiency by additionally replenishing the refrigerant charge in the refrigeration system, which facilitates the installation of different connecting pipe lengths during the user's application process and effectively improves the user's experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 is a structural schematic diagram of an air conditioner provided by an embodiment of the present invention under a first preferred implementation mode;

[0049] Figure 2 is a schematic structural diagram of an air conditioner in a second preferred implementation manner in an embodiment of the present invention;

[0050] Figure 3 is a schematic structural diagram of an air conditioner in a third preferred implementation manner in an embodiment of the present invention;

[0051] Figure 4is a schematic flow chart of the work performed by the controller in the embodiment of the present invention under the first preferred implementation mode;

[0052] Figure 5 is a schematic flow chart of the work performed by the controller in the embodiment of the present invention under the second preferred implementation mode;

[0053] Figure 6 is a schematic flow chart of the work performed by the controller in the third preferred implementation mode in the embodiment of the present invention;

[0054] Figure 7 is a schematic flow chart of the work performed by the controller in the fourth preferred implementation mode of the embodiment of the present invention;

[0055] Figure 8 is a schematic structural diagram of an air conditioner in a fourth preferred implementation manner according to an embodiment of the present invention;

[0056] Fig. 9 is a schematic flow chart of the work performed by the controller in the fifth preferred implementation mode in the embodiment of the present invention;

[0057] Fig.10 is a schematic flow chart of the work performed by the controller in the sixth preferred implementation mode in the embodiment of the present invention;

[0058] Fig.11 It is a flowchart of the work performed by the controller in the seventh preferred implementation mode of the embodiment of the present invention. DETAILED DESCRIPTION

[0059] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0060] See also Figure 1, is a schematic diagram of the structure of an air conditioner provided by an embodiment of the present invention under a first preferred implementation mode. An embodiment of the present invention provides an air conditioner, which includes a refrigeration system 10, a refrigerant regulating device 20, a pressure sensing device 30 and a controller 40. Among them, the refrigeration system 10 is used to realize the circulation of the refrigerant, thereby realizing the functions of the air conditioner such as refrigeration or heating, the refrigerant regulating device 20 is used to realize the flow regulation of the refrigerant in the refrigeration system, so that the air conditioner meets different operating conditions, the pressure sensing device includes a plurality of pressure sensors arranged at different positions, which are used to detect the pressure values ​​at different positions in the refrigeration system or the refrigerant regulating device, and the controller 40 is respectively connected to the refrigeration system 10, the refrigerant regulating device 20 and the pressure sensing device 30 to realize the acquisition and calculation of each parameter information and the issuance of corresponding control instructions.

[0061] Preferably, see Figure 2 , is a schematic diagram of the structure of the air conditioner in the second preferred embodiment of the present invention. The refrigeration system 10 includes a compressor 11, an outdoor heat exchanger 12, a throttling device 13, an indoor heat exchanger 14 and related connecting pipes. These main components are connected to form a closed and interconnected system, and the refrigerant filled in circulates in the system pipes, and the cold and heat are transported with the flow of the refrigerant.

[0062] The refrigeration system 10 can realize the functions of refrigeration and heating. In practical applications, the switching between the refrigeration mode and the heating mode can be realized by setting a four-way valve at the exhaust outlet of the compressor 11. For example, in the refrigeration mode, the compressor compresses the gaseous refrigerant into a high-temperature and high-pressure gas, and sends it to the outdoor heat exchanger for cooling. After cooling, it becomes a medium-temperature and high-pressure liquid refrigerant. After filtering and drying, the medium-temperature liquid refrigerant is throttled and reduced in pressure by a throttling device. The low-temperature and low-pressure gas-liquid mixture is evaporated by heat exchange in the indoor heat exchanger, absorbs heat in the air and vaporizes, becomes a gas, and then returns to the compressor for further compression, and continues to circulate for refrigeration.

[0063] It can be understood that the above scenario is only used as an illustration of the cooling principle of the air conditioner. In actual application, the cooling operation of the air conditioner can be completed according to actual conditions; of course, the heating principle and heating operation of the air conditioner can also refer to the existing technology and will not be repeated here.

[0064] The refrigerant regulating device 20 includes a gas-liquid storage device 21, a first control valve 22, and a second control valve 23; wherein the first end of the gas-liquid storage device 21 is connected to the pipeline on the high-pressure side of the compressor 11 through the first control valve 22; and the second end of the gas-liquid storage device 21 is connected to the pipeline on the low-pressure side of the compressor 11 through the second control valve 23. That is, the first end of the gas-liquid storage device 21 is connected to the first end of the first control valve 22, the second end of the first control valve 22 is connected to the exhaust outlet of the compressor 11, the second end of the gas-liquid storage device 21 is connected to the first end of the second control valve 23, and the second end of the second control valve 23 is connected to the return air port of the compressor 11.

[0065] In the embodiment of the present invention, the refrigerant regulating device 20 has the function of storing and releasing refrigerant. The first control valve 22 and the second control valve 23 mainly play the role of switches. When the first control valve 22 and the second control valve 23 are in the disconnected state, the refrigeration system is an independent refrigerant circulation system, and the refrigerant in the refrigeration system will not flow through the pipeline formed by the refrigerant regulating device. When the first control valve 22 or the second control valve 23 is turned on according to demand, the refrigerant in the refrigeration system may flow into the pipeline formed by the refrigerant regulating device and enter the gas-liquid storage device for storage. There may also be a situation where the refrigerant in the gas-liquid storage device flows into the refrigeration system to supplement the flow of the refrigerant circulating in the refrigeration system. Therefore, the flow of the refrigerant in the refrigeration system is regulated by the accumulation of the refrigerant in the refrigeration system and the on-off control of the first control valve 22 and the second control valve 23.

[0066] It should be noted that, when no refrigerant regulation is required, the first control valve 22 and the second control valve 23 are always in the disconnected state. Therefore, before the air conditioner is operated, the first control valve 22 and the second control valve 23 are in the disconnected state. They are only turned on when receiving a turn-on command. When the command expires or there is no command, they are both in the disconnected state. Normally, during the operation of the entire air conditioner system, the first control valve 22 and the second control valve 23 cannot be opened at the same time to avoid reliability problems.

[0067] Optionally, the first control valve 22 and the second control valve 23 are two-way valve devices.

[0068] The pressure sensing device 30 includes a first pressure sensor 31, a second pressure sensor 32 and a third pressure sensor 33. The first pressure sensor 31 is arranged on the high-pressure side pipeline of the compressor 11, and is used to detect the pressure value of the high-pressure side pipeline of the compressor; the second pressure sensor 32 is arranged on the low-pressure side pipeline of the compressor 11, and is used to detect the pressure value of the low-pressure side pipeline of the compressor; the third pressure sensor 33 is arranged between the first control valve 22 and the second control valve 23, and is used to detect the pressure value of the gas-liquid storage 21. Preferably, the third pressure sensor 33 can be arranged between the first control valve 22 and the gas-liquid storage 21.

[0069] In an embodiment of the present invention, the first pressure sensor 31, the second pressure sensor 32 and the third pressure sensor 33 send the collected refrigerant pressure values ​​at their respective locations to the controller 40 in real time, so that the controller 40 can control the refrigeration system 10 and the refrigerant regulating device 20 according to the detected pressure value information.

[0070] Preferably, see Figure 3 , is a schematic diagram of the structure of the air conditioner in the third preferred embodiment of the present invention. Based on the structure of the above air conditioner, the refrigeration system 10 of the air conditioner also includes a liquid storage tank 15, which is arranged on the pipeline between the compressor 11 and the indoor heat exchanger 14, so as to store the liquid component in the refrigerant and prevent the compressor from having a liquid hammer phenomenon.

[0071] See also Figure 4 , is a flow chart of the work performed by the controller in the first preferred implementation mode in the embodiment of the present invention. The controller 40 is used to perform steps S11 to S12:

[0072] S11, during the operation of the air conditioner, detecting the flow rate of the refrigerant in the refrigeration system;

[0073] S12. According to the flow rate of the refrigerant and the pressure value collected by the pressure sensor device, the opening of the throttling device and the on-off state of the first control valve and the second control valve are controlled to adjust the flow rate of the refrigerant in the refrigeration system.

[0074] In the embodiment of the present invention, during the power-on operation of the air conditioner, the controller 40 detects the flow rate of the refrigerant participating in the circulation in the refrigeration system 10 in real time to determine whether the refrigerant in the refrigeration system is in an excessive, insufficient or appropriate state, so as to determine whether it is necessary to reduce or increase the flow rate of the refrigerant participating in the circulation in the refrigeration system. The refrigerant flow is adjusted by controlling the gas-liquid storage to store or release the refrigerant, wherein the control method for realizing the storage and release of the refrigerant is to control it by using the pressure difference in the refrigeration system. The flow of the refrigerant in the refrigeration system is similar to the common river flow, and the throttling device is similar to the dam, which intercepts the flow through the dam, raises the water level, and forms a water level difference. The control principle of the embodiment of the present invention is similar, and the throttling device of the air conditioner is controlled to a certain extent, so that the situation that is conducive to the storage and release of the refrigerant appears before and after the throttling, and then the gas-liquid storage is controlled by controlling the first control valve or the second control valve. The pressure value of the high-pressure side of the compressor, the pressure value of the low-pressure side and the pressure value in the refrigerant regulating device 20 are an important basis for judging the pressure difference.

[0075] Therefore, after determining the flow rate of the refrigerant in the current refrigeration system, the controller 40 controls the opening size of the throttling device 13 according to the pressure value collected by the pressure sensing device 30, including the refrigerant pressure value of the high-pressure side pipeline of the compressor 11 collected by the first pressure sensor 31 as the first pressure value P1, the refrigerant pressure value of the low-pressure side pipeline of the compressor collected by the second pressure sensor 32 as the second pressure value P2, and the pressure value of the gas-liquid storage device 21 collected by the third pressure sensor 33 as the third pressure value P3, thereby adjusting the position of the refrigerant accumulation in the refrigeration system 10, and then adjusting the on-off state of the first control valve 22 and the second control valve 23 to realize the storage and release function of the gas-liquid storage device 21 for the refrigerant, thereby adjusting the flow rate of the refrigerant circulating in the refrigeration system.

[0076] By adopting the technical means of the embodiment of the present invention, a refrigerant regulating device is connected to the refrigeration system of the air conditioner to realize the storage and release of the refrigerant. During the operation of the air conditioner, the flow rate of the refrigerant in the refrigeration system is judged in real time; and according to the flow rate of the refrigerant and the pressure value collected by the pressure sensor at different positions, the opening of the throttling device in the refrigeration system and the on-off state of the refrigerant regulating device are controlled, so that during the operation of the air conditioner, the flow rate of the refrigerant in the refrigeration system can be adjusted according to different actual load conditions and the actual size of the refrigerant, so that the flow rate of the refrigerant in the refrigeration system is maintained at an appropriate value. Under high load conditions, by releasing the refrigerant in the gas-liquid storage device, the refrigerant amount of the refrigeration system is increased, the unit transportation capacity of energy is improved, and a higher capacity output of the air conditioner is achieved, and the comfort is improved. Under medium and low loads, if the amount of refrigerant in the refrigeration system is too much, the work done by the unit will be increased, and the energy consumption will increase. Therefore, by storing some excess refrigerant, it can not only meet the appropriate capacity output, but also reduce power consumption, and avoid problems such as liquid hammer due to excessive refrigerant. Under low-temperature heating conditions, the pressure on the low-pressure side of the system can also be increased by adding an appropriate amount of refrigerant, so that the low-pressure side heat exchanger is not easy to frost, thereby increasing its heating capacity. In addition, since the refrigerant flow rate of the refrigeration system in the embodiment of the present invention is adjustable, when the air conditioner needs to use a long connecting pipe, there is no need to increase the cooling or heating efficiency by additionally replenishing the refrigerant charge in the refrigeration system, which facilitates the installation of different connecting pipe lengths during the user's application process and effectively improves the user's experience.

[0077] As a preferred implementation, based on the above embodiment, in step S11, that is, detecting the flow rate of the refrigerant in the refrigeration system, specifically: detecting the flow rate level of the refrigerant in the refrigeration system; wherein the flow rate level is excessive flow, insufficient flow or moderate flow.

[0078] In an embodiment of the present invention, the controller 40 determines whether the refrigerant flow in the refrigeration system is excessive, insufficient or moderate according to the actual operating load of the air conditioner, the required target output capacity and the current refrigerant flow in the refrigeration system, and determines the refrigerant flow level.

[0079] Further, in the embodiment of the present invention, after determining the flow level of the refrigerator, the controller 40 determines whether it is necessary to control the gas-liquid storage to store refrigerant or release refrigerant according to the flow level to adjust the refrigerant flow.

[0080] In the first case, see Figure 5, is a flow chart of the work performed by the controller in the embodiment of the present invention under the second preferred implementation mode, step S12, that is, controlling the opening of the throttling device and the on-off state of the first control valve and the second control valve according to the flow rate of the refrigerant and the pressure value collected by the pressure sensor device to adjust the flow rate of the refrigerant in the refrigeration system, specifically includes steps S121 to S123:

[0081] S121, when it is determined that the flow rate of the refrigerant is excessive, determining whether the first pressure value is greater than or equal to the sum of the third pressure value and a first pressure difference threshold;

[0082] S122: If yes, control the first control valve to be turned on until the first pressure value is less than or equal to the sum of the third pressure value and the second pressure difference threshold, or when the first pressure value is less than or equal to the upper limit of a preset pressure value range, control the first control valve to be turned off;

[0083] S123. If not, reduce the opening of the throttling device until the first pressure value is greater than or equal to the sum of the third pressure value and the first pressure difference threshold, and execute: control the first control valve to be turned on until the first pressure value is less than or equal to the sum of the third pressure value and the second pressure difference threshold, or when the first pressure value is less than or equal to the upper limit value of the preset pressure value range, control the first control valve to be turned off; wherein the first pressure difference threshold is greater than the second pressure difference threshold.

[0084] Specifically, when it is determined that the flow rate of refrigerant in the refrigeration system 10 is excessive, the air conditioning system is controlled to enter a refrigerant storage mode, thereby storing the excess refrigerant in the gas-liquid storage device and reducing the refrigerant circulating in the refrigeration system.

[0085] The controller 40 pre-sets a first pressure difference threshold △P1 and a second pressure difference threshold △P2 to judge the magnitude of each pressure value detected by the pressure sensor device. Where △P1>△P2>0. The controller 40 compares the collected first pressure value P1 on the high-pressure side of the compressor 11 with the third pressure value P3 of the gas-liquid storage 21:

[0086] When P1≥P3+△P1 is satisfied, indicating that the pressure difference between the high-pressure side of the refrigeration system and the gas-liquid storage device is large enough, the first control valve 22 is controlled to be turned on, and the refrigerant on the high-pressure side of the refrigeration system flows into the gas-liquid storage device 21 with the pressure difference, and is stored in the gas-liquid storage device 21 until P1≤P3+△P2, or P1≤Ph, the first control valve 22 is controlled to be turned off; wherein Ph refers to the upper limit value of the preset pressure value range.

[0087] When P1≥P3+△P1 is not satisfied, indicating that the pressure difference between the high-pressure side of the refrigeration system and the gas-liquid storage device is not large enough, the throttling device 13 is first controlled to reduce the opening and increase the throttling, so that the refrigerant in the refrigeration system accumulates on the high-pressure side, and the first pressure value P1 is increased until P1≥P3+△P1 is satisfied. Then the first control valve 22 is controlled to be turned on, and the refrigerant on the high-pressure side of the refrigeration system flows into the gas-liquid storage device 21 with the pressure difference, and is stored in the gas-liquid storage device 21 until P1≤P3+△P2, or P1≤Ph, and the first control valve 22 is controlled to be disconnected.

[0088] It should be noted that the first pressure difference threshold △P1, the second pressure difference threshold △P2 and the upper limit value Ph of the pressure value range are pre-set, and their specific values ​​can be set according to the actual test conditions of the air conditioner, combined with different working conditions, different temperature zones, etc. of the air conditioner, and are not specifically limited here.

[0089] Furthermore, in the second case, see Figure 6 , is a schematic flow chart of the work performed by the controller in the third preferred implementation mode in the embodiment of the present invention, step S12 also includes steps S124 to S126:

[0090] S124, when it is determined that the flow rate of the refrigerant is too small, determining whether the third pressure value is greater than the sum of the second pressure value and a third pressure difference threshold;

[0091] S125: If yes, control the second control valve to be turned on until the third pressure value is less than or equal to the sum of the second pressure value and the fourth pressure difference threshold, or when the second pressure value is greater than or equal to the lower limit of a preset pressure value range, control the second control valve to be turned off;

[0092] S126, if not, reduce the opening of the throttling device until the third pressure value is greater than the sum of the second pressure value and the third pressure difference threshold, and execute: control the second control valve to be turned on until the third pressure value is less than or equal to the sum of the second pressure value and the fourth pressure difference threshold, or when the second pressure value is greater than or equal to the lower limit of the preset pressure value range, control the second control valve to be turned off. The third pressure difference threshold is greater than the fourth pressure difference threshold.

[0093] Specifically, when it is determined that the flow rate of the refrigerant in the refrigeration system 10 is too small, the air conditioner system is controlled to enter a refrigerant release mode, so that the refrigerant stored in the gas-liquid storage is released into the refrigeration system.

[0094] The controller 40 pre-sets the third pressure difference threshold △P3 and the fourth pressure difference threshold △P4 to judge the magnitude of each pressure value detected by the pressure sensor device. Among them, △P3>△P4>0. The controller 40 compares the collected third pressure value P3 of the gas-liquid storage 21 with the second pressure value P2 on the low-pressure side of the compressor 11:

[0095] When P3>P2+△P3 is satisfied, indicating that the pressure difference between the gas-liquid storage and the low-pressure side of the refrigeration system is large enough, the second control valve 23 is controlled to be turned on, and the refrigerant in the gas-liquid storage 21 flows into the refrigeration system 10 with the pressure difference to participate in the refrigeration or heating cycle, until P3≤P2+△P4, or P2≥Pl, the second control valve 23 is controlled to be turned off; where Pl refers to the lower limit of the preset pressure value range. It can be understood that Ph>Pl.

[0096] When P3>P2+△P3 is not satisfied, it indicates that the pressure difference between the gas-liquid storage device and the low-pressure side of the refrigeration system is not large enough, and the throttling device 13 is first controlled to reduce the opening and increase the throttling, so that the refrigerant in the refrigeration system accumulates on the high-pressure side, reducing the second pressure value P2, until P3>P2+△P3 is satisfied, and then the second control valve 23 is controlled to be turned on, and the refrigerant in the gas-liquid storage device 21 flows into the refrigeration system 10 with the pressure difference to participate in the refrigeration or heating cycle, until P3≤P2+△P4, or P2≥Pl, the second control valve 23 is controlled to be disconnected.

[0097] It should be noted that the third pressure difference threshold △P3, the fourth pressure difference threshold △P4 and the lower limit Pl of the pressure value range are pre-set, and their specific values ​​can be set according to the actual test conditions of the air conditioner, combined with different working conditions, different temperature zones, etc. of the air conditioner, and are not specifically limited here.

[0098] Furthermore, in the third case, see Figure 7 , is a flowchart of the work performed by the controller in the fourth preferred implementation mode in the embodiment of the present invention, step S12 also includes step S127:

[0099] S127. When it is determined that the flow rate of the refrigerant is moderate, the opening degree of the throttling device and the on-off state of the first control valve and the second control valve are maintained unchanged.

[0100] Specifically, when it is determined that the flow rate of the refrigerant in the refrigeration system 10 is moderate, there is no need to execute the storage or release mode of the refrigerant, and the controller 40 maintains the opening of the throttling device 13 unchanged, and maintains the on-off state of the first control valve 22 and the second control valve 23 unchanged, that is, the first control valve 22 and the second control valve 23 are in the disconnected state.

[0101] By adopting the technical means of the embodiments of the present invention, it is possible to effectively and accurately implement control strategies when the refrigerant flow rate in the refrigeration system is too much, too little or moderate, thereby effectively adjusting the refrigerant flow rate participating in the circulation in the refrigeration system so that the refrigerant flow rate in the refrigeration system is maintained at an appropriate value, ensuring the output capacity while taking into account the needs of energy saving and low consumption.

[0102] As a preferred embodiment, see Figure 8 , is a schematic diagram of the structure of the air conditioner in the fourth preferred embodiment of the present invention. Based on the above embodiment, the refrigerant conditioning device 20 further includes a heating device 24, which is arranged on the surface of the gas-liquid storage 21 to heat the gas-liquid storage 21.

[0103] See Fig. 9 , is a flowchart of the work performed by the controller in the fifth preferred implementation mode in the embodiment of the present invention. On the basis of executing the above steps S121 to S127, when it is determined that the flow rate of the refrigerant is too small, if the third pressure value is not greater than the sum of the second pressure value and the third pressure difference threshold, the controller 40 is further used to execute the steps:

[0104] The heating device is controlled to start running until the third pressure value is greater than the sum of the second pressure value and a third pressure difference threshold, and then the heating device is controlled to stop running.

[0105] In the embodiment of the present invention, in the second case, when the air conditioner system enters the refrigerant release mode, when P3>P2+△P3 is not satisfied, the controller 40 can not only control the throttling device 13 to reduce the opening, but also start the heating device 24 to heat the gas-liquid storage 21, thereby helping to increase the third pressure value P3. Especially under low temperature of the external environment, the temperature and air pressure of the gas-liquid storage 21 are low, and the liquid inside may be frozen. In such a harsh situation, starting the heating device 24 to heat the gas-liquid storage 21 can effectively increase the internal pressure of the gas-liquid storage, that is, the third pressure value P3.

[0106] Optionally, the heating device 24 is an electric heating belt, which is wound around the surface of the gas-liquid storage device 21 . The electric heating belt gradually heats up when powered on to heat the gas-liquid storage device 21 .

[0107] By adopting the technical means of the embodiment of the present invention, a heating device is arranged on the surface of the gas-liquid storage device, so that the internal pressure of the gas-liquid storage device can be quickly and effectively increased under extreme conditions, which is beneficial to the effective regulation of the refrigerant flow in the refrigeration system.

[0108] As a preferred embodiment, based on the above embodiment, when the air conditioner system enters the refrigerant storage mode or the refrigerant release mode, the controller 40 is further used to:

[0109] Real-time detection of the continuous working time of the air conditioner system in the current mode; wherein the current mode is a refrigerant storage mode or a refrigerant release mode;

[0110] When the continuous operation time is greater than or equal to a preset upper limit of the adjustment time, the air conditioner system is controlled to exit the refrigerant storage mode or the refrigerant release mode.

[0111] It should be noted that the preset upper limit of the adjustment time length can be set according to actual application conditions and is not specifically limited here.

[0112] By adopting the technical means of the embodiment of the present invention, it is possible to restore the normal operation of the air conditioner unit when the cooling capacity of the air conditioner is adjusted for too long, thereby ensuring that the air conditioner can provide its basic cooling or heating effect according to user needs.

[0113] It should be noted that in the refrigerant storage or release mode, the high-pressure and low-pressure protection functions are temporarily shielded, and other conventional protection functions still work normally. In special cases, even if the throttling device is adjusted, the relevant conditions may not meet the opening conditions of the first control valve or the second control valve, resulting in unsuccessful refrigerant storage or release. This is a normal phenomenon.

[0114] As a preferred embodiment, see Fig.10 , is a flowchart of the work performed by the controller in the sixth preferred implementation mode in the embodiment of the present invention. The embodiment of the present invention is further implemented on the basis of any of the above embodiments, wherein step S11 specifically includes S111 to S114:

[0115] S111, detecting a pressure value at an exhaust port of the compressor as an exhaust pressure value;

[0116] S112, when the exhaust pressure value is greater than a first exhaust pressure threshold, determining that the flow rate of the refrigerant in the refrigeration system is excessive;

[0117] S113, when the exhaust pressure value is less than a second exhaust pressure threshold, determining that the flow rate of the refrigerant in the refrigeration system is too small;

[0118] S114, when the exhaust pressure value is less than or equal to the first exhaust pressure threshold and greater than or equal to the second exhaust pressure threshold, determining that the flow rate of the refrigerant in the refrigeration system is moderate;

[0119] Wherein, the first exhaust pressure threshold is greater than the second exhaust pressure threshold.

[0120] In the embodiment of the present invention, the flow rate of the refrigerant circulating in the refrigeration system 10 can be determined according to the pressure value Pi at the exhaust port of the compressor 11. Specifically, a first exhaust pressure threshold Pi1 and a second exhaust pressure threshold Pi2 are pre-set to determine the high pressure value Pi at the exhaust port of the compressor, and Pi2 < Pi1.

[0121] When Pi>Pi1 is satisfied, it is determined that the refrigerant flow in the refrigeration system is excessive and part of the refrigerant in the refrigeration system needs to be stored in the gas-liquid storage 21, so the air-conditioning system is controlled to enter the refrigerant storage mode.

[0122] When Pi<Pi2 is satisfied, it is determined that the refrigerant flow in the refrigeration system is too small, and part of the refrigerant stored in the gas-liquid storage 21 needs to be released into the refrigeration system, so the air-conditioning system is controlled to enter the refrigerant release mode.

[0123] When Pi2≤Pi≤Pi1 is satisfied, it is determined that the refrigerant flow in the refrigeration system is appropriate, and there is no need to store or release the refrigerant, the refrigerant regulating device 20 does not operate, and the first control valve 22 and the second control valve 23 remain in the disconnected state.

[0124] More preferably, the first exhaust pressure threshold Pi1 is the sum of the preset ideal exhaust pressure value Pj and the fifth pressure difference threshold ΔP5; the second exhaust pressure threshold Pi2 is the difference between the preset ideal exhaust pressure value Pj and the sixth pressure difference threshold ΔP6. That is, Pi1 = Pj + ΔP5, Pi2 = Pj - ΔP6.

[0125] The ideal exhaust pressure value Pj, the fifth pressure difference threshold value △P5 and the sixth pressure difference threshold value △P6 are determined according to the current ambient temperature Te and the operating frequency f of the compressor 11. That is, the controller 40 pre-stores the corresponding relationship between the ambient temperature Te, the compressor operating frequency f and the ideal exhaust pressure value Pj, the fifth pressure difference threshold value △P5 and the sixth pressure difference threshold value △P6, and is used to record the specific values ​​of the ideal exhaust pressure value Pj and △P5 and △P6 pre-set in the program corresponding to the operating frequencies of different compressors at different ambient temperatures, so as to facilitate the formation of different condition judgments and the issuance of different instruction actions.

[0126] It should be noted that the ideal exhaust pressure value Pj is the ideal high pressure value under normal working conditions of the compressor, and △P5 and △P6 are non-zero positive values. The main purpose is to assume that the pressure is appropriate within a certain high pressure range, and there is no need to make variable adjustments to the refrigerant amount.

[0127] See Fig.11, is a flowchart of the work performed by the controller in the seventh preferred implementation mode in an embodiment of the present invention, wherein step S11 more specifically includes steps S111' to S115':

[0128] S111', detecting the pressure value at the exhaust port of the compressor as the exhaust pressure value Pi;

[0129] S112', obtaining the current ambient temperature and the current operating frequency of the compressor to determine the current ideal exhaust pressure value Pj, the fifth pressure difference threshold ΔP5 and the sixth pressure difference threshold ΔP6;

[0130] S113', when Pi>Pj+△P5 is satisfied, it is determined that the flow rate of the refrigerant in the refrigeration system is excessive;

[0131] S114', when Pi<Pj-△P6 is satisfied, it is determined that the flow rate of the refrigerant in the refrigeration system is too small;

[0132] S115', when Pj-ΔP6≤Pi≤Pj+ΔP5 is satisfied, it is determined that the flow rate of the refrigerant in the refrigeration system is moderate.

[0133] By adopting the technical means of the embodiments of the present invention, the load condition of the air conditioner and the required amount of refrigerant can be accurately judged according to the ambient temperature of the air conditioner and the actual operating status of the air conditioner compressor, thereby determining the current refrigerant flow level of the refrigeration system, which is conducive to accurately realizing the regulation of the refrigerant flow.

[0134] The embodiment of the present invention further provides a refrigerant adjustment method for an air conditioner, the air conditioner comprising:

[0135] Refrigeration systems, including compressors and throttling devices;

[0136] A refrigerant regulating device, comprising a gas-liquid storage device, a first control valve and a second control valve; wherein the first end of the gas-liquid storage device is connected to the pipeline on the high-pressure side of the compressor through the first control valve; the second end of the gas-liquid storage device is connected to the pipeline on the low-pressure side of the compressor through the second control valve;

[0137] a pressure sensing device, comprising a first pressure sensor disposed on the high-pressure side, a second pressure sensor disposed on the low-pressure side, and a third pressure sensor disposed between the first control valve and the second control valve;

[0138] The refrigerant adjustment method of the air conditioner comprises steps S21 to S22:

[0139] S21, during the operation of the air conditioner, detecting the flow rate of the refrigerant in the refrigeration system;

[0140] S22. According to the flow rate of the refrigerant and the pressure value collected by the pressure sensor device, control the opening of the throttling device and the on-off state of the first control valve and the second control valve to adjust the flow rate of the refrigerant in the refrigeration system.

[0141] By adopting the technical means of the embodiment of the present invention, a refrigerant regulating device is connected to the refrigeration system of the air conditioner to realize the storage and release of the refrigerant. During the operation of the air conditioner, the flow rate of the refrigerant in the refrigeration system is judged in real time; and according to the flow rate of the refrigerant and the pressure value collected by the pressure sensor at different positions, the opening of the throttling device in the refrigeration system and the on-off state of the refrigerant regulating device are controlled, so that during the operation of the air conditioner, the flow rate of the refrigerant in the refrigeration system can be adjusted according to different actual load conditions and the actual size of the refrigerant, so that the flow rate of the refrigerant in the refrigeration system is maintained at an appropriate value, the output capacity of the refrigeration system is improved under high load conditions, and the energy efficiency is improved under low load conditions, and the output capacity is ensured while taking into account the requirements of energy saving and low consumption; and, since the refrigerant flow rate of the refrigeration system in the embodiment of the present invention is adjustable, when the air conditioner needs to use a long connecting pipe in the application scenario, there is no need to increase the cooling or heating efficiency by additionally supplementing the refrigerant charge in the refrigeration system, which is convenient for the user to install different connecting pipe lengths during the application process, and effectively improves the user's use experience.

[0142] It should be noted that the refrigerant regulation method of an air conditioner provided in an embodiment of the present invention is identical to all process steps executed by a controller of an air conditioner in the above embodiment, and the working principles and beneficial effects of the two correspond one to one, so they will not be described in detail.

[0143] A person skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the above-mentioned methods. The storage medium can be a disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM), etc.

[0144] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. An air conditioner, characterized in that: include: Refrigeration systems, including compressors and throttling devices; A refrigerant regulating device, comprising a gas-liquid storage device, a first control valve and a second control valve; wherein the first end of the gas-liquid storage device is connected to the pipeline on the high-pressure side of the compressor through the first control valve; the second end of the gas-liquid storage device is connected to the pipeline on the low-pressure side of the compressor through the second control valve; a pressure sensing device, comprising a first pressure sensor disposed on the high-pressure side, a second pressure sensor disposed on the low-pressure side, and a third pressure sensor disposed between the first control valve and the second control valve; Controller for: During the operation of the air conditioner, detecting the flow rate of the refrigerant in the refrigeration system; According to the flow rate of the refrigerant and the pressure value collected by the pressure sensor, the opening of the throttling device and the on-off state of the first control valve and the second control valve are controlled to adjust the flow rate of the refrigerant in the refrigeration system; The detecting the flow rate of the refrigerant in the refrigeration system is specifically: Detecting the flow level of the refrigerant in the refrigeration system; wherein the flow level is excessive flow, insufficient flow or moderate flow; The pressure values ​​collected by the pressure sensing device include: a pressure value of the high-pressure side of the compressor collected by the first pressure sensor as a first pressure value, a pressure value of the low-pressure side of the compressor collected by the second pressure sensor as a second pressure value, and a pressure value of the gas-liquid storage device collected by the third pressure sensor as a third pressure value; The controlling the opening of the throttling device and the on-off state of the first control valve and the second control valve according to the flow rate of the refrigerant and the pressure value collected by the pressure sensor device to adjust the flow rate of the refrigerant in the refrigeration system specifically includes: When it is determined that the flow rate of the refrigerant is excessive, determining whether the first pressure value is greater than or equal to the sum of the third pressure value and a first pressure difference threshold; If yes, control the first control valve to be turned on until the first pressure value is less than or equal to the sum of the third pressure value and the second pressure difference threshold, or when the first pressure value is less than or equal to the upper limit of a preset pressure value range, control the first control valve to be turned off; If not, reduce the opening of the throttling device until the first pressure value is greater than or equal to the sum of the third pressure value and the first pressure difference threshold, and execute: control the first control valve to be turned on until the first pressure value is less than or equal to the sum of the third pressure value and the second pressure difference threshold, or when the first pressure value is less than or equal to the upper limit of a preset pressure value range, control the first control valve to be turned off; The first pressure difference threshold is greater than the second pressure difference threshold.

2. The air conditioner according to claim 1, characterized in that: The method controls the opening of the throttling device and the on-off state of the first control valve and the second control valve according to the flow rate of the refrigerant and the pressure value collected by the pressure sensor device to adjust the flow rate of the refrigerant in the refrigeration system, and further includes: When it is determined that the flow rate of the refrigerant is too small, determining whether the third pressure value is greater than the sum of the second pressure value and a third pressure difference threshold; If yes, control the second control valve to be turned on until the third pressure value is less than or equal to the sum of the second pressure value and the fourth pressure difference threshold, or when the second pressure value is greater than or equal to the lower limit of the preset pressure value range, control the second control valve to be turned off; If not, reduce the opening of the throttling device until the third pressure value is greater than the sum of the second pressure value and the third pressure difference threshold, and execute: control the second control valve to be turned on until the third pressure value is less than or equal to the sum of the second pressure value and the fourth pressure difference threshold, or when the second pressure value is greater than or equal to the lower limit of the preset pressure value range, control the second control valve to be turned off; The third pressure difference threshold is greater than the fourth pressure difference threshold.

3. The air conditioner according to claim 2, characterized in that: The refrigerant regulating device further comprises a heating device, and the heating device is arranged on the surface of the gas-liquid storage device; When it is determined that the flow rate of the refrigerant is too small, if the third pressure value is not greater than the sum of the second pressure value and the third pressure difference threshold, the controller is further configured to: The heating device is controlled to start running until the third pressure value is greater than the sum of the second pressure value and a third pressure difference threshold, and then the heating device is controlled to stop running.

4. The air conditioner according to claim 1, characterized in that: The method controls the opening of the throttling device and the on-off state of the first control valve and the second control valve according to the flow rate of the refrigerant and the pressure value collected by the pressure sensor device to adjust the flow rate of the refrigerant in the refrigeration system, and further includes: When it is determined that the flow rate of the refrigerant is moderate, the opening degree of the throttling device and the on-off state of the first control valve and the second control valve are maintained unchanged.

5. The air conditioner according to any one of claims 1 to 4, characterized in that: The detecting the flow level of the refrigerant in the refrigeration system specifically includes: Detecting a pressure value at an exhaust port of the compressor as an exhaust pressure value; The flow level of the refrigerant in the refrigeration system is determined according to the exhaust pressure value.

6. The air conditioner according to claim 5, characterized in that: The step of determining the flow level of the refrigerant in the refrigeration system according to the exhaust pressure value specifically includes: When the exhaust pressure value is greater than a first exhaust pressure threshold, it is determined that the flow rate of the refrigerant in the refrigeration system is excessive; When the exhaust pressure value is less than a second exhaust pressure threshold, it is determined that the flow rate of the refrigerant in the refrigeration system is too small; When the exhaust pressure value is less than or equal to the first exhaust pressure threshold and greater than or equal to the second exhaust pressure threshold, it is determined that the flow rate of the refrigerant in the refrigeration system is moderate; Wherein, the first exhaust pressure threshold is greater than the second exhaust pressure threshold.

7. The air conditioner according to claim 6, characterized in that: The first exhaust pressure threshold is the sum of a preset ideal exhaust pressure value and a fifth pressure difference threshold; the second exhaust pressure threshold is the difference between a preset ideal exhaust pressure value and a sixth pressure difference threshold; The ideal exhaust pressure value, the fifth pressure difference threshold, and the sixth pressure difference threshold are determined according to the current ambient temperature and the operating frequency of the compressor.

8. A refrigerant regulation method for an air conditioner, characterized in that: Applicable to the air conditioner according to any one of claims 1 to 7, the air conditioner comprising: Refrigeration systems, including compressors and throttling devices; A refrigerant regulating device, comprising a gas-liquid storage device, a first control valve and a second control valve; wherein the first end of the gas-liquid storage device is connected to the pipeline on the high-pressure side of the compressor through the first control valve; the second end of the gas-liquid storage device is connected to the pipeline on the low-pressure side of the compressor through the second control valve; a pressure sensing device, comprising a first pressure sensor disposed on the high-pressure side, a second pressure sensor disposed on the low-pressure side, and a third pressure sensor disposed between the first control valve and the second control valve; The method comprises: During the operation of the air conditioner, detecting the flow rate of the refrigerant in the refrigeration system; According to the flow rate of the refrigerant and the pressure value collected by the pressure sensor device, the opening degree of the throttling device and the on-off state of the first control valve and the second control valve are controlled to adjust the flow rate of the refrigerant in the refrigeration system.

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