Refrigerant flow rate regulation method in refrigeration system and refrigeration system

Abstract

The present application provides a method for regulating the flow rate of refrigerant in a refrigeration system, comprising steps S1, S2 and S3. In step S1, the parameters of at least two components of the refrigeration system are obtained in a predetermined order, and these parameters are judged in sequence whether they are within a preset range; if these parameters are all within the preset range, then go to step S3; if the parameters of one of the components are not within the preset range, then stop judging whether the subsequent parameters are within the preset range, determine the opening adjustment amount and response time of the flow control valve based on the parameters that are not within the preset range, and go to step S2. In step S2, adjust the opening of the flow control valve according to the above-mentioned opening adjustment amount, wait for the response time, and then go to step S1. In step S3, wait for the preset time, and then go to step S1. The judgment of the parameters of the compressor precedes the judgment of the parameters of the subcooler. The present application ensures that the performance of the compressor and the subcooler is excellent and enables the refrigeration system to operate reliably.

Description

Technical Field

[0001] The present application relates to a method for regulating the flow rate of a refrigerant, and in particular to a method for regulating the flow rate of a refrigerant in a refrigeration system. Background Art

[0002] In a refrigeration system, the refrigeration unit consists of a compressor, condenser, flow control valve, and evaporator. When the refrigeration unit is operating, the compressor draws in lower-pressure gaseous refrigerant from the evaporator, raises its pressure, and feeds it into the condenser. Inside the condenser, the higher-pressure gaseous refrigerant exchanges heat with the cooling fluid, condensing into a higher-pressure liquid refrigerant that is then fed into the throttle valve. The higher-pressure liquid refrigerant is throttled by the throttle valve to become a lower-pressure two-phase refrigerant, which is then fed into the evaporator. Inside the evaporator, the lower-pressure two-phase refrigerant exchanges heat with the refrigerated fluid, absorbing heat and evaporating into a lower-pressure gaseous refrigerant that is then fed into the compressor inlet, completing the refrigeration cycle. Summary of the Invention

[0003] During refrigeration unit operation, a certain refrigerant level must be maintained in the evaporator. If the refrigerant level in the evaporator is too low, the evaporator's heat exchange performance will deteriorate. If the refrigerant level in the evaporator is too high, the liquid droplets entrained in the gaseous refrigerant cannot be completely separated, causing a certain amount of liquid droplets to be entrained in the gaseous refrigerant sucked into the compressor, resulting in reduced compressor efficiency. In severe cases, it can damage the compressor, leading to unreliable system operation.

[0004] Furthermore, the inventors have recognized that a certain refrigerant level must be maintained in the condenser during refrigeration unit operation. For example, in a refrigeration unit with a subcooler within the condenser, to ensure that the refrigerant entering the subcooler is pure liquid, the refrigerant level in the condenser is typically greater than or equal to the height of the subcooler, so that the entire subcooler is submerged in the saturated liquid pool within the condenser. A refrigerant level that is too low in the condenser can cause refrigerant gas to enter the subcooler, severely impacting subcooler efficiency, increasing the subcooler pressure drop, and even causing the flow control valve to lose its regulating capacity. More specifically, if the refrigerant received by the flow control valve contains refrigerant gas, when the refrigerant gas reaches a certain level, even fully opening the flow control valve may not be able to deliver the required refrigerant flow to the evaporator. In this case, the flow control valve loses its regulating capacity. Consequently, the flow control valve is unable to regulate the liquid level in the evaporator to maintain evaporator performance, potentially causing the refrigeration system to operate improperly. Furthermore, a refrigerant level that is too high in the condenser can result in an increased refrigerant charge within the condenser.

[0005] In order to overcome the above-mentioned problems caused by abnormal refrigerant liquid level in the refrigeration system, the present application adjusts the flow rate of the refrigerant in the refrigeration system so that the refrigerant liquid level in the evaporator and the condenser is within the desired height range or reaches the desired height, thereby ensuring the excellent working performance of the compressor and the subcooler, or ensuring the excellent working performance of the compressor, subcooler and evaporator, and then ensuring the adjustment performance of the flow regulating valve to stabilize the control of the refrigerant flow, so that the refrigeration system can operate normally and reliably, and improve the circulation efficiency of the entire refrigeration system.

[0006] According to the first aspect of the present application, the present application provides a method for regulating the flow of refrigerant in a refrigeration system. The refrigeration system includes the following components: a compressor, a condenser, a subcooler, a flow regulating valve and an evaporator. The method includes steps S1, S1 and S3. In step S1, the parameters of the components of the refrigeration system are obtained according to a predetermined order, and whether the parameters of at least two components of the refrigeration system are within a preset range is judged in sequence. If the parameters of the at least two components are within the preset range, the process proceeds to step S3. If the parameters of one of the components are not within the preset range, the process stops judging whether the subsequent parameters are within the preset range, and the opening adjustment amount and response time of the flow regulating valve are determined based on the parameters that are not within the preset range in step S1, and then the process proceeds to step S2.

[0007] In step S2, the flow control valve opening is adjusted based on the flow control valve opening adjustment amount. After waiting for a response time, the process returns to step S1. In step S3, after waiting for a preset time, the process returns to step S1. The parameters of at least two components of the refrigeration system in step S1 include parameters of the compressor and parameters of the subcooler. The predetermined order is such that the compressor parameters are determined before the subcooler parameters.

[0008] According to the first aspect of the present application, the compressor parameter is the compressor's exhaust superheat B. Step S1 includes the following sub-steps S1.1, S1.2, and S1.9. In sub-step S1.1, the compressor's exhaust superheat B is obtained, and a determination is made as to whether the exhaust superheat B is greater than or equal to the exhaust superheat target value M2. If the exhaust superheat B is greater than or equal to the exhaust superheat target value M2, the subsequent sub-steps of step S1 are continued; otherwise, the flow control valve's reduced opening adjustment amount and response time are determined based on the exhaust superheat B, the subsequent sub-steps of step S1 are stopped, and the process proceeds to step S2.

[0009] In sub-step S1.2, the sub-cooler parameters are obtained and a determination is made as to whether the sub-cooler parameters are within a preset range. If so, the subsequent sub-steps of step S1 are executed. Otherwise, the flow control valve opening adjustment amount and response time are determined based on the sub-cooler parameters, and the subsequent sub-steps of step S1 are discontinued and the process proceeds to step S2.

[0010] In sub-step S1.9, executing this step indicates that multiple parameters of the refrigeration system are within their preset ranges, and the process goes to step S3.

[0011] According to the first aspect of the present application, the parameters of at least two components of the refrigeration system in step S1 include the heat exchange small temperature difference change rate A of the evaporator. Step S1 also includes a sub-step S1.3 located after sub-step S1.2 and before sub-step S1.9. In sub-step S1.3, the heat exchange small temperature difference change rate A of the evaporator is obtained, and it is determined whether the heat exchange small temperature difference change rate A of the evaporator is less than or equal to the heat exchange small temperature difference change rate target value M1. If the heat exchange small temperature difference change rate A is less than or equal to the heat exchange small temperature difference change rate target value M1, then continue to execute the subsequent sub-steps of step S1; otherwise, determine the increased opening adjustment amount and response time of the flow control valve according to the heat exchange small temperature difference change rate A, stop executing the subsequent sub-steps of step S1 and go to step S2.

[0012] According to the first aspect of the present application, in step S1.2, the following sub-steps S1.2.1 and S1.2.2 are executed. In sub-step S1.2.1, the subcooler pressure drop ΔP is obtained, and a determination is made as to whether the subcooler pressure drop ΔP is within the target pressure drop range [M3 - ΔM3, M3 + ΔM3]. If the pressure drop ΔP is within the target pressure drop range [M3 - ΔM3, M3 + ΔM3], the process proceeds to step S1.9; otherwise, the process proceeds to step S1.2.2.

[0013] In sub-step S1.2.2, a determination is made as to whether the pressure drop ΔP is greater than the maximum value M3+ΔM3 within the target pressure drop range [M3-ΔM3, M3+ΔM3]. If the pressure drop ΔP is greater than the maximum value M3+ΔM3, the flow control valve's opening adjustment and response time are determined to decrease based on the pressure drop ΔP being greater than the maximum value M3+ΔM3, and the process proceeds to step S2. Otherwise, the flow control valve's opening adjustment and response time are determined to increase based on the pressure drop ΔP being less than the minimum value M3-ΔM3 within the target pressure drop range [M3-ΔM3, M3+ΔM3], and the process proceeds to step S2. M3 is the target pressure drop value, and ΔM3 is the pressure drop stagnation threshold.

[0014] According to the first aspect of the present application, in step S1.2, the outlet temperature T of the subcooler is obtained. subc.out and subcooler outlet pressure P subc.out The saturation temperature T liq.sat , and determine the outlet temperature T of the subcooler subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat Is the difference less than zero? If the outlet temperature T subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.satIf the difference is less than zero, then continue to execute the subsequent sub-steps of step S1. Otherwise, according to the outlet temperature T subc.out and subcooler outlet pressure P subc.out The saturation temperature T liq.sat Determine the reduced opening adjustment amount and response time of the flow control valve, and go to step S2.

[0015] According to the first aspect of the present application, in step S1.2, the following sub-steps S1.2.1, S1.2.2-1, S1.2.2-2, S1.2.3-1, S1.2.3-2 and S1.2.4 are performed. In step S1.2.1, the subcooling degree T of the subcooler is obtained. subcooling , subcooling change rate C and pressure drop ΔP.

[0016] In step S1.2.2-1, determine the supercooling degree T subcooling Is it within the first subcooling preset range? If the subcooling T subcooling If it is within the first subcooling preset range, go to step S1.9; otherwise, go to step S1.2.2-2.

[0017] In step S1.2.2-2, determine the supercooling degree T subcooling Is it within the second subcooling preset range? subcooling If it is within the second preset range of supercooling, go to step S1.2.3-1; otherwise, go to step S1.2.3-2.

[0018] In step S1.2.3-1, determine whether the pressure drop ΔP is within the first preset pressure drop range. If the pressure drop ΔP is within the first preset pressure drop range, proceed to step S1.2.4; otherwise, determine the reduced opening adjustment amount and response time of the flow control valve, and proceed to step S2.

[0019] In step S1.2.3-2, a determination is made as to whether the pressure drop ΔP is within a second preset pressure drop range. If the pressure drop ΔP is within the second preset pressure drop range, the flow control valve opening adjustment amount and response time are determined, and the process proceeds to steps S2 (340, 342). Otherwise, the flow control valve opening adjustment amount and response time are determined, and the process proceeds to steps S2 (340, 342).

[0020] In step S1.2.4, determine whether the subcooling rate of change C is within the preset subcooling rate of change range. If so, proceed to step S1.9. Otherwise, determine the amount of opening adjustment required for the flow control valve and the response time, and proceed to step S2.

[0021] The first subcooling preset range is the subcooling target range [T target-sub -ΔT sub, T target-sub +ΔT sub ], the second subcooling preset range is smaller than the subcooling target range [T target-sub -ΔT sub , T target-sub +ΔT sub The minimum value T in ] target-sub -ΔT sub The first pressure drop preset range is less than M3-ΔM3, the second pressure drop preset range is less than or equal to M3+ΔM3, and the supercooling change rate preset range is less than or equal to the supercooling change rate target value M4. target-sub is the target value of subcooling, ΔT sub is the subcooling hysteresis threshold, M3 is the pressure drop target value, and ΔM3 is the pressure drop hysteresis threshold.

[0022] According to the first aspect of the present application, in step S1.2, the pressure drop ΔP of the subcooler is obtained, and a determination is made as to whether the pressure drop ΔP is less than or equal to a target pressure drop value M3. If the pressure drop ΔP is less than or equal to the target pressure drop value M3, the process proceeds to step S1.3. Otherwise, the amount of opening adjustment to be reduced and the response time of the flow control valve are determined based on the pressure drop ΔP, and the process proceeds to step S2.

[0023] According to the first aspect of the present application, the parameters of the refrigeration system are acquired based on the pressure detected by the pressure detection device and / or the temperature detected by the temperature detection device.

[0024] According to a first aspect of the present application, the subcooler is provided in the condenser.

[0025] According to a second aspect of the present application, a refrigeration system is provided, comprising a compressor, a condenser, a subcooler, a flow control valve, an evaporator, several detection devices, and a control device. The compressor, condenser, flow control valve, and evaporator are sequentially connected. The several detection devices are configured to detect the pressure and / or temperature of at least two components of the refrigeration system. The control device includes a processor and is configured to execute the aforementioned method.

[0026] The parameters of the components of the refrigeration system are within the preset range, indicating that the components are optimized and have excellent working performance. In one embodiment, the present application first optimizes the compressor and then optimizes the subcooler in the process of adjusting the refrigerant flow, thereby optimizing the refrigeration system as a whole. In another embodiment, the present application first optimizes the compressor, then optimizes the subcooler, and then optimizes the evaporator, thereby optimizing the refrigeration system as a whole. The present application prioritizes ensuring excellent compressor performance to enable the refrigeration system to operate normally and reliably, and then ensures excellent subcooler performance to prevent the flow control valve from losing its regulating ability, thereby ensuring the normal operation of the evaporator and the normal operation of the refrigeration system. Therefore, the present application can reduce the time that the refrigeration system is in an abnormal working state, reduce the risk of abnormal operation suffered by the refrigeration system, and thereby ensure the service life of the refrigeration system.

[0027] In addition, the present application uses the pressure drop of the subcooler to quickly determine abnormal operation of the subcooler, so as to adjust the flow control valve in real time to make the subcooler work with excellent performance, thereby ensuring the adjustment performance of the flow control valve in real time to stabilize the control of the refrigerant flow, ensuring the normal and reliable operation of the refrigeration system, and improving the circulation efficiency of the entire refrigeration system. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings are not drawn to scale. In the drawings, each identical or nearly identical component that is represented in different figures is represented by a like reference numeral. For clarity, not every component may be labeled in every figure. In the drawings:

[0029] Figure 1 shows a block diagram of a refrigeration system according to the present application;

[0030] Figure 2 Shown Figure 1 A schematic diagram of an embodiment of some components of a refrigeration system is shown in FIG;

[0031] Figure 3 A flow chart showing a method for regulating the flow of refrigerant in a refrigeration system is provided;

[0032] Figure 4 Shown Figure 3 Detailed flowchart of the first embodiment of step S1 in the flowchart shown in FIG;

[0033] Figure 4-1 Shown Figure 4 A detailed flow chart diagram of one embodiment of step 422 in the flow chart diagram shown in FIG;

[0034] Figure 5 Shown Figure 3A detailed flow chart of a second embodiment of step S1 in the flow chart shown in FIG.

[0035] Figure 6 Shown Figure 3 A detailed flow chart of the third embodiment of step S1 in the flow chart shown in FIG.

[0036] Figure 6-1 Shown Figure 6 A detailed flowchart of one embodiment of steps 610 and 622 in the flowchart shown in FIG.

[0037] Figure 7 Shown Figure 3 Detailed flowchart of the fourth embodiment of step S1 in the flowchart shown in FIG;

[0038] Figure 8 Shown Figure 3 A detailed flow chart of the fifth embodiment of step S1 in the flow chart shown in FIG; and

[0039] Figure 9 Shown Figure 1 A block diagram of the control device in the refrigeration system is shown in FIG. DETAILED DESCRIPTION

[0040] The specific embodiments of the present application will be described below with reference to the accompanying drawings of this specification. It should be understood that, where possible, the same or similar reference numerals used in this application refer to the same components.

[0041] Figure 1 A block diagram of the refrigeration system 100 of the present application is shown, which is used to illustrate the main functional modules of the software and hardware of the refrigeration system 100.

[0042] like Figure 1 As shown, the refrigeration system 100 of the present application includes the following components: a compressor 101, a condenser 102, a subcooler 105, a flow regulating valve 103 and an evaporator 104. In particular, the subcooler 105 is arranged in the condenser 102. The compressor 101, the condenser 102, the subcooler 105, the flow regulating valve 103 and the evaporator 104 are connected in sequence. When the refrigeration system 100 is running, the refrigerant flows through the compressor 101, the condenser 102, the subcooler 105, the flow regulating valve 103 and the evaporator 104 in sequence, and then returns to the compressor 101 to circulate. Pressure sensors and temperature sensors are also provided on the various components of the refrigeration system 100 for detecting the parameters of each component to obtain the operating status of each component.

[0043] The refrigeration system 100 further includes a control device 106, which includes a processor 107. The control device 106 can obtain the parameters of the above-mentioned components of the refrigeration system 100 detected, and process these parameters through the processor 107 to output a control signal for adjusting the opening of the flow control valve. The control signal is then output to the flow control valve 103 to adjust the opening of the flow control valve 103, thereby optimizing the refrigeration system 100.

[0044] like Figure 1 As shown, on the compressor 101, for example, at the exhaust port of the compressor 101 (see Figure 2 ), a pressure sensor 111 and a temperature sensor 112 are provided. The pressure sensor 111 is used to detect the exhaust pressure P of the compressor 101. dis The exhaust pressure P of the compressor 101 is detected via the connecting line 121. dis The temperature sensor 112 is used to detect the exhaust temperature T of the compressor 101. dis and transmits the detected exhaust temperature T of the compressor 101 to the dis Transmitted to the control device 106.

[0045] On the condenser 102, for example, the top of the condenser 102 (see Figure 2 ), a pressure sensor 113 is provided. The pressure sensor 113 is used to detect the condensing pressure P of the condenser 102. cond and the condensing pressure P of the condenser 102 is detected via the connecting line 123. cond Transmitted to the control device 106. On the condenser 102, for example, on the liquid outlet pipe at the bottom of the condenser 102 (see Figure 2 ), a pressure sensor 114 and a temperature sensor 115 are also provided. The pressure sensor 114 is used to detect the outlet pressure P of the subcooler 105. subc.out and the outlet pressure P of the subcooler 105 is detected via the connecting line 124. subc.out The temperature sensor 115 is used to detect the outlet temperature T of the subcooler 105. subc.out and transmit the detected outlet temperature T of the subcooler 105 to the subc.out Transmitted to the control device 106.

[0046] On the evaporator 104, for example, at the water outlet of the evaporator 104 (see Figure 2 ), a temperature sensor 116 is provided. The temperature sensor 116 is used to detect the outlet water temperature T of the evaporator 104. evapWater.out The outlet water temperature T of the evaporator 104 is detected by connecting line 126. evapWater.outis transmitted to the control device 106. On the evaporator 104, for example, the top of the evaporator 104 (see Figure 2 ), a pressure sensor 117 is also provided. The pressure sensor 117 is used to detect the pressure P of the evaporator 104. evap and the pressure P of the evaporator 104 is detected via the connecting line 127. evap Transmitted to the control device 106.

[0047] The control device 106 receives the exhaust pressure P of the compressor 101. dis , the exhaust temperature T of the compressor 101 dis , the condensing pressure P of the condenser 102 cond , outlet pressure P of subcooler 105 subc.out , outlet temperature T of subcooler 105 subc.out , the outlet water temperature T of the evaporator 104 evapWater.out and the pressure P of the evaporator 104 evap The flow control valve 103 is processed to output a control signal for the opening adjustment amount of the flow control valve, and the control signal is output to the flow control valve 103 through the connecting line 128. The flow control valve 103 adjusts its opening according to the control signal for the opening adjustment amount to optimize the refrigeration system 100, for example, to ensure the excellent working performance of the compressor 101 and the subcooler 105, or to ensure the excellent working performance of the compressor 101, the subcooler 105 and the evaporator 104, thereby ensuring the regulating performance of the flow control valve 103 to stabilize the control of the refrigerant flow, so that the refrigeration system 100 operates normally and reliably, and the cycle efficiency of the entire refrigeration system 100 is improved.

[0048] Figure 2 Shown Figure 1 Schematic diagram of an embodiment of some components of a refrigeration system 100 (including a compressor 101, a condenser 102, a subcooler 105, a flow regulating valve 103 and an evaporator 104) is shown in FIG.

[0049] like Figure 2 As shown, the compressor 101, condenser 102, flow control valve 103 and evaporator 104 are connected in sequence, and the subcooler 105 is arranged in the condenser 102, specifically near the outlet of the bottom of the condenser 102. The evaporator 104 is provided with a falling film tube bundle 131 and a flooded tube bundle 132.

[0050] During operation of the refrigeration system 100, the compressor 101 compresses the low-temperature, low-pressure gaseous refrigerant drawn from the evaporator 104 to a high-temperature, high-pressure state for output to the condenser 102. The condenser 102 exchanges heat between the high-temperature, high-pressure gaseous refrigerant and the cooling fluid to cool and condense it into a room-temperature, high-pressure liquid refrigerant, which is then output to the subcooler 105. The subcooler 105 further cools the room-temperature, high-pressure liquid refrigerant into a low-temperature, high-pressure liquid refrigerant, which is then output to the flow control valve 103. The flow control valve 103 reduces the pressure of the low-temperature, high-pressure liquid refrigerant into a low-temperature, low-pressure two-phase refrigerant, which is then output to the evaporator 104. The evaporator 104 exchanges heat between the low-temperature, low-pressure two-phase refrigerant and the refrigeration fluid to evaporate it into a low-temperature, low-pressure gaseous refrigerant, which is then output to the compressor 101, thus completing the refrigeration cycle.

[0051] In the condenser 102, if the refrigerant liquid level is too low, the refrigerant gas will enter the subcooler 105, seriously affecting the efficiency of the subcooler 105, and causing the pressure drop of the subcooler 105 to increase, and even causing the flow control valve 103 to lose its regulating ability. In order to ensure that the refrigerant entering the subcooler 105 is in a pure liquid state, the refrigerant liquid level height H in the condenser 102 is usually greater than or equal to the height of the subcooler 105, so that the entire subcooler 105 is submerged in the saturated liquid pool of the condenser 102. Moreover, in the condenser 102, if the refrigerant liquid level is too high, the refrigerant charge in the condenser 102 will increase. Therefore, it is necessary to ensure that the refrigerant liquid level of the condenser 102 is within the desired height range or reaches the desired height.

[0052] In the evaporator 104, the refrigerant liquid level should usually be kept at a level equivalent to the top of the full liquid tube bundle 132 to prevent the refrigerant liquid level in the evaporator 104 from being too low, resulting in a deterioration in the heat exchange performance of the evaporator 104. The refrigerant liquid level in the evaporator 104 should also not be too high, otherwise the droplets entrained in the gaseous refrigerant will not be completely separated, causing the compressor 101 to entrain a certain amount of droplets in the gaseous refrigerant sucked from the evaporator 104, thereby reducing the efficiency of the compressor 101 and even causing damage to the compressor 101, making it impossible for the refrigeration system 100 to operate reliably. Therefore, it is necessary to ensure that the refrigerant liquid level in the evaporator 104 is within the desired height range or reaches the desired height.

[0053] The present application obtains the parameters of the various components of the refrigeration system 100 based on pressure sensors and / or temperature sensors, and adjusts the flow rate of the refrigerant based on these parameters to ensure that the refrigerant liquid level in the evaporator and the condenser is within the desired height range or reaches the desired height, thereby optimizing the operation of the refrigeration system 100.

[0054] like Figure 2As shown, a pressure sensor 111 and a temperature sensor 112 are provided at the exhaust port of the compressor 101 to detect the exhaust pressure P of the compressor respectively. dis and the compressor exhaust temperature T dis A pressure sensor 113 is provided on the top of the condenser 102 to detect the condensing pressure P of the condenser. cond The liquid outlet pipe at the bottom of the condenser 102 is provided with a pressure sensor 114 and a temperature sensor 115 to detect the outlet pressure P of the subcooler respectively. subc.out and the outlet temperature of the subcooler T subc.out (Also called, outlet temperature T at the outlet of the subcooler subc.out A temperature sensor 116 is provided at the water outlet of the evaporator 104 to detect the water outlet temperature T evapWater.out A pressure sensor 117 is provided on the top of the evaporator 104 to detect the pressure P of the evaporator. evap .

[0055] In one embodiment, the parameters of the compressor 101 include the exhaust gas superheat B of the compressor 101. The exhaust gas superheat B can be obtained by the following formula: B = compressor exhaust gas temperature T dis -Compressor exhaust saturation temperature T dis.sat . The exhaust temperature of the compressor is T dis Detected by temperature sensor 112. The exhaust gas saturation temperature T of the compressor dis.sat Can be based on the compressor discharge pressure P dis To obtain, for example, by the following formula: T dis.sat =F(refrigerant,P dis ), where F(refrigerant,P dis ) is based on refrigerant and P dis The function is the independent variable, and refrigerant is the name of the refrigerant, such as R134a, R1234ze(E), R1233zd(E), etc. The above function with the refrigerant as the independent variable is different for different refrigerants. The exhaust pressure P of the compressor dis Detected by the pressure sensor 111. In other embodiments, the parameters of the compressor 101 include other suitable parameters.

[0056] In one embodiment, the parameters of the subcooler 105 include a pressure drop ΔP of the subcooler 105. The pressure drop ΔP can be obtained by the following formula: ΔP = condensing pressure P of the condenser cond - outlet pressure of subcooler P subc.out The condensing pressure of the condenser is P cond Detected by pressure sensor 113. The outlet pressure P of the subcooler subc.out Detected by pressure sensor 114 .

[0057] In one embodiment, the parameters of the subcooler 105 include the outlet temperature T of the subcooler 105. subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat The difference between the outlet temperature and the subc.out Detected by temperature sensor 115. Subcooler outlet pressure P subc.out The saturation temperature T liq.sat Based on the outlet pressure P of the subcooler subc.out To obtain, for example, by the following formula: T liq.sat =F(refrigerant,P subc.out ), where F(refrigerant,P subc.out ) is based on refrigerant and P subc.out is a function of the independent variable, refrigerant is the name of the refrigerant. The outlet pressure P of the subcooler subc.out Detected by pressure sensor 114 .

[0058] In one embodiment, the parameters of the subcooler 105 include the subcooling degree T of the subcooler 105. subcooling , the rate of change of subcooling degree C and the pressure drop ΔP of the subcooler 105. The subcooling degree T of the subcooler subcooling It can be obtained by the following formula: T subcooling = outlet temperature of subcooler T subc.out -Condensation saturation temperature T of the condenser cond.sat . Subcooler outlet temperature T subc.out Detected by temperature sensor 115. Condensation saturation temperature T cond.sat Based on the condensing pressure P of the condenser cond To obtain, for example, by the following formula: T cond.sat =F(refrigerant,P cond ), where F(refrigerant,P cond ) is based on refrigerant and P cond is a function of the independent variable, and refrigerant is the name of the refrigerant. The subcooling change rate C can be obtained by the following formula: Where Δt represents a time interval, ΔT subcooling It represents the change in subcooling degree within the time interval Δt. The pressure drop ΔP of the subcooler can be obtained by the above formula, that is, ΔP = condensing pressure P of the condenser cond - outlet pressure of subcooler P subc.out .

[0059] In other embodiments, the parameters of the subcooler 105 include other suitable parameters.

[0060] In one embodiment, the parameters of the evaporator 104 include a small heat exchange temperature difference change rate A of the evaporator 104. The small heat exchange temperature difference T of the evaporator approach.evap It represents the degree to which the evaporation saturation temperature of the evaporator is close to the outlet water temperature of the evaporator water side. The smaller the minimum temperature difference of the evaporator, the better the heat exchange effect of the evaporator. approach.evap It can be obtained by the following formula: T approach.evap = Water outlet temperature T at the evaporator outlet evapWater.out - Evaporator saturation temperature T evap.sat The water outlet temperature at the evaporator outlet is T evapWater.out Detected by temperature sensor 116. Evaporation saturation temperature T evap.sat Based on the evaporator pressure P evap To obtain, for example, by the following formula: T evap.sat =F(refrigerant,P evap ), where F(refrigerant,P evap ) is based on refrigerant and P evap is a function of the independent variable, where refrigerant is the name of the refrigerant. Evaporation saturation temperature T evap.sat Detected by pressure sensor 117. The evaporator's heat exchange small temperature difference change rate A can be obtained by the following formula:

[0061]

[0062] Where Δt represents a time interval, ΔT approach.evap It indicates the change of the small temperature difference of the evaporator during the time interval Δt.

[0063] Some specific embodiments of this application (see Figure 4-Figure 8 ) Use the above method to obtain the exhaust superheat B of the compressor 101, the heat exchange small temperature difference change rate A of the evaporator 104, the pressure drop ΔP of the subcooler 105, and the outlet temperature T subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat The difference between the two, and the subcooling degree T of the subcooler 105 subcooling , subcooling change rate C and pressure drop ΔP.

[0064] Figure 3 A flow chart of a method for regulating the flow rate of refrigerant in the refrigeration system 100 is shown.

[0065] The flow regulation method of the refrigerant of the present application includes the following cyclic steps S1, S2 and S3. Step S1 includes the following steps: obtaining the parameters of the components of the refrigeration system 100 according to a predetermined order, and sequentially judging whether the parameters of at least two components of the refrigeration system 100 are within the preset range; if the parameters of the at least two components are within the preset range, then proceeding to step S3; if the parameters of one of the components are not within the preset range, then stopping judging whether the subsequent parameters are within the preset range, and determining the opening adjustment amount and response time of the flow control valve according to the parameters that are not within the preset range in step S1, and then proceeding to step S2. Step S2 includes the following steps: adjusting the opening of the flow control valve 103 according to the opening adjustment amount of the flow control valve, waiting for the response time, and then going to step S1. Step S3 includes the following steps: waiting for the preset time, and then going to step S1.

[0066] In specific operations, such as Figure 3 As shown, at step 302 , the refrigerant flow rate regulation method 300 starts to be executed, and then proceeds from step 302 to step 304 .

[0067] At step 304 , parameters of a first component in the refrigeration system 100 are obtained, and then the process proceeds from step 304 to step 306 .

[0068] At step 306, a determination is made as to whether the parameters of the first component are within a preset range. If the parameters of the first component are within the preset range (i.e., step 306.2 is reached), the process proceeds to step 308. If the parameters of the first component are not within the preset range (i.e., step 306.1 is reached), the process proceeds to step 338. In step 338, the opening adjustment amount and response time of the flow control valve 103 are determined based on the parameters of the first component not being within the preset range.

[0069] At step 308 , parameters of a second component in the refrigeration system 100 are obtained, and then the process proceeds from step 308 to step 310 .

[0070] At step 310, a determination is made as to whether the parameters of the second component are within a preset range. If the parameters of the second component are within the preset range (i.e., step 310.2 is reached), the process proceeds to the subsequent steps. If the parameters of the second component are not within the preset range (i.e., step 310.1 is reached), the process proceeds to step 338. In step 338, the opening adjustment amount and response time of the flow control valve 103 are determined based on the parameters of the second component not within the preset range.

[0071] The subsequent steps forwarded by step 310.2 include continuing to acquire parameters of subsequent components in a predetermined sequence and determining whether the parameters of the subsequent components are within a preset range. If the parameters of the subsequent components are within the preset range, the component parameter acquisition and determination operations are continued in the predetermined sequence. If the parameters of the subsequent components are not within the preset range, the process proceeds to step 338, where the opening adjustment amount and response time of the flow control valve 103 are determined based on the parameters of the subsequent components that are not within the preset range.

[0072] After continuing the component parameter acquisition and judgment operations as above, the process proceeds to step 330. In step 330, the parameters of the Mth component are acquired, and then the process proceeds to step 332. In step 332, it is determined whether the parameters of the Mth component are within the preset range. If the parameters of the Mth component are within the preset range (i.e., step 332.2 is reached), it indicates that the parameters of the multiple components of the refrigeration system 100 are all within their preset ranges, and the refrigeration system 100 is now optimized, and the process proceeds to step 334. If the parameters of the Mth component are not within the preset range (i.e., step 332.1 is reached), the process proceeds to step 338. In step 338, the opening adjustment amount and response time of the flow control valve 103 are determined based on the parameters of the Mth component that are not within the preset range.

[0073] As previously described, in step 338, the opening adjustment amount and response time of the flow control valve 103 are determined based on the parameters of the first component, the second component, or the Mth component that are not within the preset range. The process then proceeds from step 338 to step 340. In step 340, the opening of the flow control valve 103 is adjusted based on the opening adjustment amount, and the process then proceeds from step 340 to step 342. In step 342, the response time is waited for, and the process then proceeds from step 342 to step 304, where the parameters of the first component are acquired and subsequent operations are resumed. In other words, after the opening adjustment of the flow control valve 103 is performed, the process returns to the initial state, where the component parameters are acquired and determined again in the predetermined order. This process continues until the parameters of the multiple components are within their preset ranges, indicating that the refrigeration system 100 has been optimized.

[0074] As mentioned above, after the refrigeration system 100 reaches optimization, it goes to step 334. At step 334, wait for a preset time period, and then go to step 336 from step 334. At step 336, determine whether the refrigeration system 100 needs to be shut down. If the refrigeration system 100 needs to be shut down, go to step 344 to end the flow regulation of the refrigerant. If the refrigeration system 100 does not need to be shut down, go to step 304 and re-execute the judgment of the component parameters of the refrigeration system 100 and the adjustment of the flow control valve 103, that is, the optimization judgment and adjustment of the refrigeration system 100. After adjusting the flow control valve 103 to an appropriate opening and allowing the refrigerant to circulate in the refrigeration system 100 for a period of time, the refrigeration system 100 may no longer be in an optimized state, for example, the parameters of one or several components are not within the preset range. Therefore, it is necessary to continuously monitor the parameters of each component of the refrigeration system 100 and adjust the opening of the flow regulating valve 103 accordingly when the parameters of the component are not within the preset range. Therefore, without shutting down, the refrigeration system 100 needs to return to the initial operation after reaching the optimization, and re-execute the judgment of the component parameters of the refrigeration system 100 and the adjustment of the flow regulating valve 103 to ensure that the refrigeration system 100 is in an optimized state during operation.

[0075] Step S1 includes Figure 3 Steps 304, 306, 308, 310 ... 330, 332, 338 in step S2 include Figure 3 Steps 340 and 342 in step S3 include Figure 3 Step 334 in .

[0076] In step S1 (including Figure 3 In steps 304, 306, 308, 310 ... 330, 332, 338 of the refrigeration system 100, the parameters of at least two components of the refrigeration system 100 include the parameters of the compressor 101 and the parameters of the subcooler 105. The predetermined order is that the parameters of the compressor 101 are judged before the parameters of the subcooler 105 (see Figure 4-Figure 8 ). The parameter of the component is within the preset range, indicating that the component has been optimized and has excellent working performance. In one embodiment, in the process of adjusting the refrigerant flow, the present application first optimizes the compressor 101 and then optimizes the subcooler 105 (see Figure 4-Figure 8 ), which can give priority to ensuring the excellent performance of the compressor so that the refrigeration system can operate normally and reliably, thereby reducing the time the refrigeration system is in an abnormal working state, reducing the risk of abnormal operation suffered by the refrigeration system, and thus ensuring the service life of the refrigeration system.

[0077] In another embodiment, in the process of adjusting the refrigerant flow, the present application first optimizes the compressor 101, then optimizes the subcooler 105, and then optimizes the evaporator 104 (see Figure 7-Figure 8 ). This application gives priority to ensuring that the compressor has excellent performance, then ensures that the subcooler has excellent performance and then ensures that the evaporator has excellent performance, which can reduce the time that the refrigeration system is in an abnormal working state, reduce the risk of abnormal operation suffered by the refrigeration system, and then ensure the service life of the refrigeration system. Abnormal operation of the compressor can cause damage to the compressor, making it impossible for the refrigeration system to operate reliably. When the compressor is running optimally, abnormal operation of the subcooler (for example, the refrigerant entering the subcooler contains gaseous refrigerant) will reduce the efficiency of the subcooler, and even cause the flow control valve to lose its regulating ability, so that the liquid level in the evaporator cannot be adjusted to ensure the performance of the evaporator, and even make the refrigerant level in the evaporator too low so that the refrigeration system cannot operate normally. When both the compressor and the subcooler are running optimally, abnormal operation of the evaporator will reduce the heat exchange effect of the evaporator, and the refrigeration system will still operate normally. Therefore, ensuring that the compressor reaches the highest priority for optimization, followed by ensuring that the subcooler reaches optimization, and then ensuring that the evaporator has excellent performance, can reduce the time that the refrigeration system is in an abnormal working state, and reduce the risk of abnormal operation suffered by the refrigeration system.

[0078] Furthermore, in the present application, the parameters of the subcooler 105 include a pressure drop ΔP of the subcooler 105. Determining the pressure drop ΔP of the subcooler 105 can quickly determine whether the subcooler 105 is operating abnormally, and timely (e.g., in real time) adjust the flow control valve 103 to ensure good operating performance of the subcooler 105. This ensures the regulating performance of the flow control valve to stabilize the control of the refrigerant flow, allowing the refrigeration system to operate normally and reliably, thereby improving the cycle efficiency of the entire refrigeration system.

[0079] Figure 4 Shown Figure 3 Detailed flowchart diagram 400 of the first embodiment of step S1 (including steps 304, 306, 308, 310, 338) in the flowchart shown in FIG.

[0080] like Figure 4 As shown by Figure 3 Step 302 in Go to Figure 4 At step 404 , the exhaust gas superheat B of the compressor 101 is obtained, and then the process goes to step 406 .

[0081] At step 406, determine whether the exhaust superheat B of the compressor 101 is greater than or equal to the exhaust superheat target value M2. If the exhaust superheat B of the compressor 101 is greater than or equal to the exhaust superheat target value M2 (i.e., reaching step 406.2), it means that the exhaust superheat B of the compressor 101 is appropriate, the compressor 101 is optimized, the refrigerant liquid level in the evaporator 104 meets the requirements, and the current opening of the flow control valve 103 is appropriate, then go to step 408 from step 406.2. If the exhaust superheat B of the compressor 101 is less than the exhaust superheat target value M2 (i.e., reaching step 406.1), then go to step 420. In step 420, the reduced opening adjustment amount and response time of the flow control valve 103 are determined based on the fact that the exhaust superheat B of the compressor 101 is less than the exhaust superheat target value M2, and then go to step 420. Figure 3 Step 340 in the flow control valve 103 is used to adjust the opening of the flow control valve 103 based on the reduced opening adjustment amount. The fact that the exhaust gas superheat B is less than the target exhaust gas superheat value M2 indicates that the exhaust gas superheat B is too low. Therefore, the opening of the flow control valve 103 needs to be reduced to lower the refrigerant liquid level in the evaporator 104 and prevent the refrigerant gas drawn from the evaporator 104 by the compressor 101 from being carried over with liquid. In one embodiment, the opening adjustment amount of the flow control valve 103 is determined based on the value of the exhaust gas superheat B.

[0082] In step 408 , the pressure drop ΔP of the subcooler 105 is acquired, and then the process proceeds from step 408 to step 410 .

[0083] At step 410, it is determined whether the pressure drop ΔP of the subcooler 105 is within the target pressure drop interval [M3-ΔM3, M3+ΔM3], where M3 is the target pressure drop value and ΔM3 is the pressure drop stagnation threshold. If the pressure drop ΔP of the subcooler 105 is within the target pressure drop interval [M3-ΔM3, M3+ΔM3] (i.e., reaching step 410.2), it means that the pressure drop of the subcooler 105 is appropriate, the subcooler 105 is optimized, the refrigerant liquid level in the condenser 102 meets the requirements, and the current opening of the flow control valve 103 is appropriate. At the same time, reaching step 410.2 also indicates that the parameters of the compressor and the subcooler are within the preset range, the compressor and the subcooler are optimized, and thus the refrigeration system 100 is optimized as a whole, then the process is transferred from step 410.2 to step 410. Figure 3 Step 334 in the process is used to wait for the response time. If the pressure drop ΔP of the subcooler 105 is not within the target pressure drop range [M3-ΔM3, M3+ΔM3] (i.e., step 410.1 is reached), the process goes to step 422. In step 422, the amount of opening adjustment to decrease or increase the flow control valve 103 and the response time are determined based on the fact that the pressure drop ΔP of the subcooler 105 is not within the target pressure drop range [M3-ΔM3, M3+ΔM3]. Then, step 422 is used to go to step 423. Figure 3Step 340 in the flow control valve 103 adjusts the opening of the flow control valve 103 according to the opening adjustment amount of the flow control valve 103.

[0084] Figure 4 Steps 420 and 422 in the Figure 3 Step 338 in .

[0085] Figure 4-1 Shown Figure 4 A detailed flow chart diagram of one embodiment of step 422 in the flow chart diagram is shown in FIG.

[0086] like Figure 4-1 As shown by Figure 4 Step 410.1 in Go to Figure 4-1 At step 422.0, it is determined whether the pressure drop ΔP of the subcooler 105 is greater than the maximum value M3+ΔM3 in the pressure drop target range [M3-ΔM3, M3+ΔM3].

[0087] If the pressure drop ΔP of the subcooler 105 is greater than the maximum value M3+ΔM3, then the process goes from step 422.0 to step 422.1. At step 422.1, the amount of opening adjustment and the response time of the flow control valve 103 are determined based on the fact that the pressure drop ΔP of the subcooler 105 is greater than the maximum value M3+ΔM3, and then the process goes from step 422.1 to step 422.2. Figure 3 Step 340 in the flow control valve 103 is used to adjust the opening of the flow control valve 103 according to the reduced opening adjustment amount of the flow control valve 103. The pressure drop ΔP of the subcooler 105 is greater than the maximum value M3+ΔM3, indicating that the refrigerant level at the inlet of the subcooler 105 is low and gaseous refrigerant is entering the subcooler 105. In this case, the opening of the flow control valve 103 needs to be reduced to increase the refrigerant level in the condenser 102.

[0088] If the pressure drop ΔP of the subcooler 105 is not greater than the maximum value M3+ΔM3, that is, the pressure drop ΔP of the subcooler 105 is less than the minimum value M3-ΔM3 in the pressure drop target range [M3-ΔM3, M3+ΔM3], then the process goes from step 422.0 to step 422.2. At step 422.2, the increased opening adjustment amount and response time of the flow control valve 103 are determined based on the pressure drop ΔP of the subcooler 105 being less than the minimum value M3-ΔM3, and then the process goes from step 422.2 to step 422. Figure 3 Step 340 in the flow control valve 103 is used to adjust the opening of the flow control valve 103 based on the increased opening adjustment amount. If the pressure drop ΔP of the subcooler 105 is less than the minimum value M3-ΔM3, it indicates that the refrigerant level at the inlet of the subcooler 105 is sufficient and no gaseous refrigerant is entering the subcooler 105. Therefore, the opening of the flow control valve 103 should be appropriately increased. In one embodiment, the opening adjustment amount of the flow control valve 103 is determined based on the value of the pressure drop ΔP.

[0089] Figure 5 Shown Figure 3 Detailed flowchart diagram 500 of the second embodiment of step S1 (including steps 304, 306, 308, 310, 338) in the flowchart shown in FIG.

[0090] like Figure 5 As shown by Figure 3 Step 302 in Go to Figure 5 At step 504 , the exhaust gas superheat B of the compressor 101 is obtained, and then the process goes to step 506 .

[0091] At step 506, it is determined whether the exhaust gas superheat B of the compressor 101 is greater than or equal to the exhaust gas superheat target value M2. If the exhaust gas superheat B of the compressor 101 is greater than or equal to the exhaust gas superheat target value M2 (i.e., reaching step 506.2), the compressor 101 is optimized, and the process goes to step 508. If the exhaust gas superheat B of the compressor 101 is less than the exhaust gas superheat target value M2 (i.e., reaching step 506.1), the process goes to step 520. In step 520, the amount of opening adjustment and the response time of the flow control valve 103 are determined based on the fact that the exhaust gas superheat B of the compressor 101 is less than the exhaust gas superheat target value M2, and then the process goes to step 520. Figure 3 Step 340 in the flow control valve 103 is to adjust the opening of the flow control valve 103 according to the reduced opening adjustment amount of the flow control valve 103. In one embodiment, the opening adjustment amount of the flow control valve 103 is determined based on the value of the exhaust gas superheat B. Figure 5 Steps 504 and 506 in Figure 4 Step 404 and step 406 in are substantially the same.

[0092] At step 508, the outlet temperature T of the subcooler 105 is obtained. subc.out and subcooler outlet pressure P subc.out The saturation temperature T liq.sat , then go from step 508 to step 510.

[0093] At step 510, the outlet temperature T of the subcooler 105 is determined. subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat Is the difference less than zero? If the outlet temperature of the subcooler 105 is T subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat The difference between the outlet temperature of the subcooler 105 and the outlet pressure P is less than zero (ie, reaching step 510.2), indicating that the outlet temperature of the subcooler 105 is less than the outlet pressure P subc.outThe difference in saturation temperature between the subcooler and the subcooler is appropriate, the subcooler 105 is optimized, the refrigerant liquid level in the condenser 102 meets the requirements, and the current opening of the flow control valve 103 is appropriate. At the same time, reaching step 510.2 indicates that the parameters of the compressor and the subcooler are within the preset range. The compressor and subcooler are both optimized, and thus the refrigeration system 100 is optimized as a whole. Then, step 510.2 is transferred to step 510. Figure 3 Step 334 in the waiting time is to wait for the response. If the outlet temperature of the subcooler 105 is T subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat If the difference between the two is greater than or equal to zero (i.e., reaching step 510.1), then go to step 522. In step 522, according to the outlet temperature T of the subcooler 105, subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat The difference is greater than or equal to zero to determine the reduced opening adjustment amount and response time of the flow control valve 103, and then go to step 522 Figure 3 Step 340 in the flow control valve 103 is to adjust the opening of the flow control valve 103 according to the reduced opening adjustment amount of the flow control valve 103. The outlet temperature T of the subcooler 105 subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat If the difference is greater than or equal to zero, it means that the refrigerant level at the inlet of the subcooler 105 is low, and gaseous refrigerant enters the subcooler 105. At this time, it is necessary to reduce the opening of the flow control valve 103 to increase the refrigerant level in the condenser 102. In one embodiment, based on the outlet temperature T subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat The difference between them is used to determine the opening adjustment amount of the flow control valve 103.

[0094] Figure 5 Steps 520 and 522 in the Figure 3 Step 338 in .

[0095] Figure 6 Shown Figure 3 FIG. 6 is a detailed flowchart diagram 600 of a third embodiment of step S1 (including steps 304 , 306 , 308 , 310 , and 338 ) in the flowchart shown in FIG.

[0096] like Figure 6 As shown by Figure 3 Step 302 in Go to Figure 6 At step 604 , the exhaust gas superheat B of the compressor 101 is obtained, and then the process goes to step 606 .

[0097] At step 606, it is determined whether the exhaust gas superheat B of the compressor 101 is greater than or equal to the exhaust gas superheat target value M2. If the exhaust gas superheat B of the compressor 101 is greater than or equal to the exhaust gas superheat target value M2 (i.e., reaching step 606.2), the compressor 101 is optimized, and the process goes to step 608. If the exhaust gas superheat B of the compressor 101 is less than the exhaust gas superheat target value M2 (i.e., reaching step 606.1), the process goes to step 620. In step 620, the amount of opening adjustment and the response time of the flow control valve 103 are determined based on the fact that the exhaust gas superheat B of the compressor 101 is less than the exhaust gas superheat target value M2, and then the process goes to step 620. Figure 3 Step 340 in the flow control valve 103 is to adjust the opening of the flow control valve 103 according to the reduced opening adjustment amount of the flow control valve 103. In one embodiment, the opening adjustment amount of the flow control valve 103 is determined based on the value of the exhaust gas superheat B. Figure 6 Steps 604 and 606 in Figure 4 Step 404 and step 406 in are substantially the same.

[0098] At step 608, the subcooling degree T of the subcooler 105 is obtained. subcooling , subcooling rate of change C and pressure drop ΔP, then go from step 608 to step 610.

[0099] At step 610, the subcooling degree T of the subcooler 105 is determined. subcooling , whether the subcooling change rate C and the pressure drop ΔP meet one of the following conditions: (1) T target-sub -ΔT sub ≤T subcooling ≤T target-sub +ΔT sub , and (2)T subcooling <T target-sub -ΔT sub , ΔP<M3-ΔM3 and C≤M4, where T target-sub is the target value of subcooling, ΔT sub is the subcooling stagnation threshold, M3 is the pressure drop target value, ΔM3 is the pressure drop stagnation threshold, and M4 is the subcooling change rate target value. subcooling, the subcooling change rate C and the pressure drop ΔP meet one of the conditions (1) and (2) (i.e., reaching step 610.2), indicating that the subcooling, subcooling change rate and pressure drop of the subcooler 105 are appropriate, the subcooler 105 is optimized, the refrigerant liquid level in the condenser 102 meets the requirements, and the current opening of the flow control valve 103 is appropriate. At the same time, reaching step 610.2 indicates that the parameters of the compressor and the subcooler are within the preset range, the compressor and the subcooler are optimized, and thus the refrigeration system 100 is optimized as a whole, then the process goes from step 610.2 to step 610.3. Figure 3 Step 334 in the waiting time is to wait for the response. If the subcooling degree T of the subcooler 105 is subcooling If the subcooling rate C and the pressure drop ΔP do not satisfy any of the conditions (1) and (2) (i.e., reaching step 610.1), then go to step 622. In step 622, according to the subcooling T of the subcooler 105, subcooling , the subcooling rate of change C and the pressure drop ΔP are used to determine the opening adjustment amount and response time of the flow control valve 103, and then step 622 is turned to Figure 3 Step 340 in the flow control valve 103 adjusts the opening of the flow control valve 103 according to the opening adjustment amount of the flow control valve 103.

[0100] Figure 6 Steps 620 and 622 in the Figure 3 Step 338 in .

[0101] Figure 6-1 Shown Figure 6 Detailed flowchart of one embodiment of step 610 and step 622 in the flowchart shown in FIG.

[0102] like Figure 6-1 As shown by Figure 6 Step 608 in Go to Figure 6-1 Step 640. At step 640, the subcooling degree T of the subcooler 105 is determined. subcooling Is it in the target range of supercooling degree [T target-sub -ΔT sub , T target-sub +ΔT sub If the subcooling degree T of the subcooler 105 subcooling In the subcooling target range [T target-sub -ΔT sub , T target-sub +ΔT sub], indicating that the subcooling degree of the subcooler 105 is appropriate, the subcooler 105 is optimized, the refrigerant liquid level in the condenser 102 meets the requirements, and the current opening of the flow control valve 103 is appropriate. It also shows that the parameters of the compressor and the subcooler are within the preset range, the compressor and the subcooler are optimized, and thus the refrigeration system 100 is optimized as a whole, then go to Figure 3 Step 334 in the waiting time is to wait for the response. If the subcooling degree T of the subcooler 105 is subcooling Not in the target subcooling range [T target-sub -ΔT sub , T target-sub +ΔT sub ], then go to step 642.

[0103] At step 642, the subcooling degree T of the subcooler 105 is determined. subcooling Is it less than the target range of supercooling [T target-sub -ΔT sub , T target-sub +ΔT sub The minimum value T in ] target-sub -ΔT sub If the subcooling degree T of the subcooler 105 subcooling Less than the minimum value T target-sub -ΔT sub , then go to step 644. If the subcooling degree T of the subcooler 105 subcooling Not less than the minimum value T target-sub -ΔT sub , that is, the subcooling degree T of the subcooler 105 subcooling Greater than the target range of supercooling [T target-sub -ΔT sub , T target-sub +ΔT sub The maximum value T in ] target-sub +ΔT sub , then go to step 648.

[0104] At step 644, it is determined whether the pressure drop ΔP of the subcooler 105 is less than the minimum value M3-ΔM3 in the pressure drop target range [M3-ΔM3, M3+ΔM3]. If the pressure drop ΔP of the subcooler 105 is less than the minimum value M3-ΔM3, the process proceeds to step 646. If the pressure drop ΔP of the subcooler 105 is greater than or equal to the minimum value M3-ΔM3, then T subcooling <T target-sub -ΔT subAnd ΔP≥M3-ΔM3, indicating that the refrigerant level at the inlet of the subcooler 105 is low, and gaseous refrigerant has entered the subcooler 105. At this time, it is necessary to reduce the opening of the flow control valve 103 to increase the refrigerant level in the condenser 102, and then go to step 654 from step 644. At step 654, determine the opening adjustment amount and response time of the flow control valve 103, and then go to step 654. Figure 3 Step 340 in the flow control valve 103 is to adjust the opening of the flow control valve 103 according to the reduced opening adjustment amount of the flow control valve 103.

[0105] At step 646, it is determined whether the subcooling change rate C of the subcooler 105 is less than or equal to the subcooling change rate target value M4. If the subcooling change rate C of the subcooler 105 is less than or equal to the subcooling change rate target value M4, then T subcooling <T target-sub -ΔT sub , ΔP<M3-ΔM3 and C≤M4, indicating that the subcooling degree, pressure drop and subcooling degree change rate of the subcooler 105 are appropriate, the subcooler 105 is optimized, the refrigerant liquid level in the condenser 102 meets the requirements, and the current opening of the flow control valve 103 is appropriate. It also indicates that the parameters of the compressor and the subcooler are within the preset range, the compressor and the subcooler are optimized, and thus the refrigeration system 100 is optimized as a whole. Then, step 646 is transferred to step 646. Figure 3 If the subcooling change rate C of the subcooler 105 is greater than the subcooling change rate target value M4, then T subcooling <T target-sub -ΔT sub , ΔP<M3-ΔM3 and C>M4, indicating that the refrigerant level at the inlet of the subcooler 105 is low, and gaseous refrigerant has entered the subcooler 105. At this time, it is necessary to reduce the opening of the flow control valve 103 to increase the refrigerant level in the condenser 102, and then go from step 646 to step 656. At step 656, determine the opening adjustment amount and response time of the flow control valve 103, and then go from step 656 to step 656. Figure 3 Step 340 in the flow control valve 103 is to adjust the opening of the flow control valve 103 according to the reduced opening adjustment amount of the flow control valve 103.

[0106] At step 648, it is determined whether the pressure drop ΔP of the subcooler 105 is less than or equal to the maximum value M3+ΔM3 in the pressure drop target range [M3-ΔM3, M3+ΔM3]. If the pressure drop ΔP of the subcooler 105 is less than or equal to the maximum value M3+ΔM3, then T subcooling >T target-sub +ΔT subIf ΔP≤M3+ΔM3, it means that the refrigerant level at the inlet of the subcooler 105 is sufficient and no gaseous refrigerant enters the subcooler 105. Then, the opening of the flow control valve 103 needs to be increased, and the process goes from step 648 to step 650. At step 650, the increase in the opening adjustment amount and the response time of the flow control valve 103 are determined, and then the process goes from step 650 to step 660. Figure 3 Step 340 in the flow control valve 103 is to adjust the opening of the flow control valve 103 according to the increased opening adjustment amount of the flow control valve 103.

[0107] At step 648, if the pressure drop ΔP of the subcooler 105 is greater than the maximum value M3+ΔM3, then T subcooling >T target-sub +ΔT sub And ΔP>M3+ΔM3, indicating that the refrigerant level at the inlet of the subcooler 105 is low, and gaseous refrigerant has entered the subcooler 105. At this time, it is necessary to reduce the opening of the flow control valve 103 to increase the refrigerant level in the condenser 102, and then go to step 652 from step 648. At step 652, determine the opening adjustment amount and response time of the flow control valve 103, and then go to step 652. Figure 3 Step 340 in the flow control valve 103 is to adjust the opening of the flow control valve 103 according to the reduced opening adjustment amount of the flow control valve 103.

[0108] In one embodiment, based on the subcooling degree T of the subcooler 105 subcooling The opening adjustment amount of the flow control valve 103 is determined by the value of , the value of the supercooling change rate C and the value of the pressure drop ΔP.

[0109] Figure 7 Shown Figure 3 Detailed flowchart diagram 700 of the fourth embodiment of step S1 (including steps 304, 306, 308, 310, 330, 332, 338) in the flowchart shown in FIG.

[0110] like Figure 7 As shown by Figure 3 Step 302 in Go to Figure 7 At step 704 , the exhaust gas superheat B of the compressor 101 is obtained, and then the process goes to step 706 .

[0111] At step 706, it is determined whether the exhaust gas superheat B of the compressor 101 is greater than or equal to the exhaust gas superheat target value M2. If the exhaust gas superheat B of the compressor 101 is greater than or equal to the exhaust gas superheat target value M2 (i.e., reaching step 706.2), the compressor 101 is optimized, and the process goes to step 708. If the exhaust gas superheat B of the compressor 101 is less than the exhaust gas superheat target value M2 (i.e., reaching step 706.1), the process goes to step 720. In step 720, the amount of opening adjustment and the response time of the flow control valve 103 are determined based on the fact that the exhaust gas superheat B of the compressor 101 is less than the exhaust gas superheat target value M2, and then the process goes to step 720. Figure 3 Step 340 in the flow control valve 103 is to adjust the opening of the flow control valve 103 according to the reduced opening adjustment amount of the flow control valve 103. In one embodiment, the opening adjustment amount of the flow control valve 103 is determined based on the value of the exhaust gas superheat B. Figure 7 Steps 704 and 706 in Figure 4 Step 404 and step 406 in are substantially the same.

[0112] In step 708 , the pressure drop ΔP of the subcooler 105 is acquired, and then the process proceeds from step 708 to step 710 .

[0113] At step 710, it is determined whether the pressure drop ΔP of the subcooler 105 is less than or equal to the pressure drop target value M3. If the pressure drop ΔP of the subcooler 105 is less than or equal to the pressure drop target value M3 (i.e., reaching step 710.2), it means that the pressure drop of the subcooler 105 is appropriate, the subcooler 105 is optimized, the refrigerant liquid level in the condenser 102 meets the requirements, and the current opening of the flow control valve 103 is appropriate, then the process goes from step 710.2 to step 712. If the pressure drop ΔP of the subcooler 105 is greater than the pressure drop target value M3 (i.e., reaching step 710.1), then the process goes to step 722. In step 722, the amount of reduced opening adjustment and the response time of the flow control valve 103 are determined based on the fact that the pressure drop ΔP of the subcooler 105 is greater than the pressure drop target value M3, then the process goes from step 722 to step 722. Figure 3 Step 340 in the flow control valve 103 is used to adjust the opening of the flow control valve 103 based on the reduced opening adjustment amount of the flow control valve 103. If the pressure drop ΔP in the subcooler 105 is greater than the target pressure drop value M3, it indicates that the refrigerant level at the inlet of the subcooler 105 is low, and gaseous refrigerant is entering the subcooler 105. In this case, the opening of the flow control valve 103 needs to be reduced to increase the refrigerant level in the condenser 102. In one embodiment, the opening adjustment amount of the flow control valve 103 is determined based on the value of the pressure drop ΔP.

[0114] At step 712 , the heat exchange small temperature difference change rate A of the evaporator 104 is obtained, and then the process goes from step 712 to step 714 .

[0115] At step 714, determine whether the heat exchange small temperature difference change rate A of the evaporator 104 is less than or equal to the heat exchange small temperature difference change rate target value M1. If the heat exchange small temperature difference change rate A of the evaporator 104 is less than or equal to the heat exchange small temperature difference change rate target value M1 (i.e., reaching step 714.2), it means that the heat exchange small temperature difference change rate of the evaporator 104 is appropriate, the evaporator 104 is optimized, the refrigerant liquid level in the evaporator 104 meets the requirements, and the current opening of the flow control valve 103 is appropriate. At the same time, reaching step 714.2 also indicates that the parameters of the compressor, the subcooler and the evaporator are all within the preset range, the compressor, the subcooler and the evaporator are all optimized, and thus the refrigeration system 100 is optimized as a whole, then step 714.2 is turned to Figure 3 If the small heat exchange temperature difference change rate A of the evaporator 104 is greater than the target value M1 of the small heat exchange temperature difference change rate (i.e., step 714.1 is reached), then the process goes to step 724. In step 724, the increased opening adjustment amount and response time of the flow control valve 103 are determined based on the fact that the small heat exchange temperature difference change rate A of the evaporator 104 is greater than the target value M1 of the small heat exchange temperature difference change rate, and then the process goes to step 724. Figure 3 Step 340 in the flow control valve 103 is used to adjust the opening of the flow control valve 103 based on the increased opening adjustment amount. If the heat exchange small temperature difference change rate A of the evaporator 104 is greater than the target heat exchange small temperature difference change rate value M1, it indicates that the refrigerant level in the evaporator is sufficient. Therefore, the opening of the flow control valve 103 can be increased to bring the evaporator small temperature difference change rate A closer to the target heat exchange small temperature difference change rate value M1. In one embodiment, the opening adjustment amount of the flow control valve 103 is determined based on the value of the heat exchange small temperature difference change rate A.

[0116] Figure 7 Steps 720, 722, and 724 in the Figure 3 Step 338 in .

[0117] Figure 8 Shown Figure 3 Detailed flowchart diagram 800 of the fifth embodiment of step S1 (including steps 304, 306, 308, 310, 330, 332, 338) in the flowchart shown in FIG.

[0118] like Figure 8 As shown by Figure 3 Step 302 in Go to Figure 8 At step 804 , the exhaust gas superheat B of the compressor 101 is obtained, and then the process goes to step 806 .

[0119] At step 806, it is determined whether the exhaust gas superheat B of the compressor 101 is greater than or equal to the exhaust gas superheat target value M2. If the exhaust gas superheat B of the compressor 101 is greater than or equal to the exhaust gas superheat target value M2 (i.e., reaching step 806.2), the compressor 101 is optimized, and the process goes to step 808. If the exhaust gas superheat B of the compressor 101 is less than the exhaust gas superheat target value M2 (i.e., reaching step 806.1), the process goes to step 820. In step 820, the amount of opening adjustment and the response time of the flow control valve 103 are determined based on the fact that the exhaust gas superheat B of the compressor 101 is less than the exhaust gas superheat target value M2, and then the process goes to step 820. Figure 3 Step 340 in the flow control valve 103 is to adjust the opening of the flow control valve 103 according to the reduced opening adjustment amount of the flow control valve 103. In one embodiment, the opening adjustment amount of the flow control valve 103 is determined based on the value of the exhaust gas superheat B. Figure 8 Steps 804 and 806 in Figure 7 Step 704 and step 706 in are substantially the same.

[0120] At step 808, the outlet temperature T of the subcooler 105 is obtained. subc.out and subcooler outlet pressure P subc.out The saturation temperature T liq.sat , then go from step 808 to step 810.

[0121] At step 810, the outlet temperature T of the subcooler 105 is determined. subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat Is the difference less than zero? If the outlet temperature of the subcooler 105 is T subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat The difference between the outlet temperature of the subcooler 105 and the outlet pressure P is less than zero (ie, reaching step 810.2), indicating that the outlet temperature of the subcooler 105 is less than the outlet pressure P subc.out If the difference in saturation temperature between the subcooler 105 and the condenser 102 is appropriate, the subcooler 105 is optimized, the refrigerant level in the condenser 102 meets the requirements, and the current opening of the flow control valve 103 is appropriate, then step 810.2 is transferred to step 812. subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat If the difference between the two is greater than or equal to zero (i.e., reaching step 810.1), then go to step 822. In step 822, according to the outlet temperature T of the subcooler 105 subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.satThe difference is greater than or equal to zero to determine the reduced opening adjustment amount and response time of the flow control valve 103, and then go to step 822 Figure 3 Step 340 in the flow control valve 103 is to adjust the opening of the flow control valve 103 according to the reduced opening adjustment amount of the flow control valve 103. The outlet temperature T of the subcooler 105 subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat If the difference is greater than or equal to zero, it means that the refrigerant level at the inlet of the subcooler 105 is low, and gaseous refrigerant enters the subcooler 105. At this time, it is necessary to reduce the opening of the flow control valve 103 to increase the refrigerant level in the condenser 102. In one embodiment, based on the outlet temperature T subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat The difference between them is used to determine the opening adjustment amount of the flow control valve 103.

[0122] At step 812 , the heat exchange small temperature difference change rate A of the evaporator 104 is obtained, and then the process goes from step 812 to step 814 .

[0123] At step 814, determine whether the heat exchange small temperature difference change rate A of the evaporator 104 is less than or equal to the heat exchange small temperature difference change rate target value M1. If the heat exchange small temperature difference change rate A of the evaporator 104 is less than or equal to the heat exchange small temperature difference change rate target value M1 (i.e., reaching step 814.2), it means that the heat exchange small temperature difference change rate of the evaporator 104 is appropriate, the evaporator 104 is optimized, the refrigerant liquid level in the evaporator 104 meets the requirements, and the current opening of the flow control valve 103 is appropriate. At the same time, reaching step 814.2 also indicates that the parameters of the compressor, the subcooler and the evaporator are all within the preset range, the compressor, the subcooler and the evaporator are all optimized, and thus the refrigeration system 100 is optimized as a whole, then step 814.2 is turned to Figure 3 If the small heat exchange temperature difference change rate A of the evaporator 104 is greater than the target value M1 of the small heat exchange temperature difference change rate (i.e., step 814.1 is reached), then the process goes to step 824. In step 824, the increased opening adjustment amount and response time of the flow control valve 103 are determined based on the fact that the small heat exchange temperature difference change rate A of the evaporator 104 is greater than the target value M1 of the small heat exchange temperature difference change rate, and then the process goes to step 824. Figure 3 Step 340 in the flow control valve 103 is to adjust the opening of the flow control valve 103 according to the increased opening adjustment amount of the flow control valve 103. In one embodiment, the opening adjustment amount of the flow control valve 103 is determined based on the value of the heat exchange small temperature difference change rate A. Figure 8 Steps 812 and 814 in Figure 7 Step 712 and step 714 in are substantially the same.

[0124] Figure 8 Steps 820, 822, and 824 in the Figure 3 Step 338 in .

[0125] Figure 9 Shown Figure 1 FIG. 1 is a block diagram of the control device 106 in the refrigeration system 100. Figure 9 As shown, the control device 106 includes a bus 901, a processor 902, a memory 903, an input interface 904, and an output interface 905. The processor 902, the memory 903, the input interface 904, and the output interface 905 are connected to the bus 901. The processor 902 can read a program (or instruction) from the memory 903 and execute the program (or instruction) to perform data processing and control functions of various components of the refrigeration system 100. The processor 902 can also write data or programs (or instructions) into the memory 903. The memory 903 can store programs (instructions) or data. By executing the instructions in the memory 903, the processor 902 can control the memory 903, the input interface 904, and the output interface 905.

[0126] The input interface 904 is configured to receive the exhaust pressure P of the compressor 101 from the pressure sensor 111 via the connection line 121. dis , receiving the exhaust temperature T of the compressor 101 from the temperature sensor 112 via the connection line 122 dis , receiving the condensing pressure P of the condenser 102 from the pressure sensor 113 through the connecting line 123 cond , receiving the outlet pressure P of the subcooler 105 from the pressure sensor 114 through the connecting line 124 subc.out , receiving the outlet temperature T of the subcooler 105 from the temperature sensor 115 via the connecting line 125 subc.out , receiving the outlet water temperature T of the evaporator 104 from the temperature sensor 116 via the connecting line 126 evapWater.out and the pressure P of the evaporator 104 received from the pressure sensor 117 via the connecting line 127. evap The input interface 904 is further configured to convert the received parameters into a signal recognizable by the processor 902 and output the signal to the processor 902. The processor 902 is configured to process (e.g., calculate, determine) the received signal to output an adjustment control signal for the opening adjustment amount of the flow control valve 103. The processor 902 is further configured to determine a duration control signal corresponding to a response duration and a preset duration, and control the operation of the refrigeration system 100 based on the duration control signal.

[0127] The output interface 905 is configured to receive a regulation control signal from the processor 902, convert the regulation control signal into an output signal suitable for the flow control valve 103, and send the output signal to the flow control valve 103 through the connecting line 128 so that the flow control valve 103 can adjust its opening based on the received output signal.

[0128] Although the present application has been described in conjunction with the examples of the embodiments outlined above, it is likely that various alternatives, modifications, variations, improvements and / or substantial equivalents, whether known or currently or soon foreseeable, will be apparent to those skilled in the art. In addition, the technical effects and / or technical problems described in this specification are exemplary and not restrictive; so the disclosures in this specification may be used to solve other technical problems and have other technical effects and / or may solve other technical problems. Therefore, the examples of the embodiments of the present application as stated above are intended to be illustrative and not restrictive. Various changes may be made without departing from the spirit or scope of the present application. Therefore, the present application is intended to include all known or earlier developed alternatives, modifications, variations, improvements and / or substantial equivalents.

Claims

1. A method for regulating the flow rate of a refrigerant in a refrigeration system (100), wherein the refrigeration system (100) comprises the following components: a compressor (101), a condenser (102), a subcooler (105), a flow regulating valve (103), and an evaporator (104), wherein: The method comprises the following steps: S1: Acquire parameters of components of the refrigeration system according to a predetermined sequence, and sequentially determine whether the parameters of at least two components of the refrigeration system are within a preset range; if the parameters of the at least two components are both within the preset range, proceed to step S3; if the parameter of one of the components is not within the preset range, stop determining whether subsequent parameters are within the preset range, and determine the opening adjustment amount and response time of the flow control valve based on the parameter that is not within the preset range in step S1, and then proceed to step S2; S2 (340, 342): adjusting the opening of the flow control valve (103) according to the opening adjustment amount of the flow control valve, waiting for a response time, and then going to step S1; S3 (334): After waiting for a preset time, go to step S1; The parameters of at least two components of the refrigeration system in step S1 include parameters of a compressor (101) and parameters of a subcooler (105), and the predetermined order is: the parameters of the compressor (101) are judged before the parameters of the subcooler (105).

2. The method for regulating the flow rate of refrigerant in a refrigeration system (100) according to claim 1, characterized in that: The parameter of the compressor (101) is the exhaust gas superheat B of the compressor (101), and the step S1 comprises the following sub-steps: S1.1: Obtaining the exhaust gas superheat B of the compressor (101), and determining whether the exhaust gas superheat B is greater than or equal to an exhaust gas superheat target value M2; if the exhaust gas superheat B is greater than or equal to the exhaust gas superheat target value M2, then continuing to execute the subsequent sub-steps of step S1; Otherwise, the reduced opening adjustment amount and response time of the flow control valve are determined according to the exhaust superheat B, and the subsequent sub-steps of step S1 are stopped and the process goes to step S2; S1.2: Obtaining parameters of the subcooler (105) and determining whether the parameters of the subcooler (105) are within a preset range; if the parameters of the subcooler (105) are within the preset range, continuing to execute the subsequent sub-steps of step S1; otherwise, determining the opening adjustment amount and response time of the flow control valve according to the parameters of the subcooler (105), stopping executing the subsequent sub-steps of step S1 and turning to step S2; S1.9: Executing this step indicates that multiple parameters of the refrigeration system are within their preset ranges, and go to step S3.

3. The method for regulating the flow rate of refrigerant in a refrigeration system (100) according to claim 2, characterized in that: The parameters of at least two components of the refrigeration system in step S1 include the heat exchange small temperature difference change rate A of the evaporator (104), and step S1 further includes a sub-step S1.3 located after sub-step S1.2 and before sub-step S1.9: S1.3: Obtain the small heat exchange temperature difference change rate A of the evaporator (104), and determine whether the small heat exchange temperature difference change rate A of the evaporator (104) is less than or equal to the small heat exchange temperature difference change rate target value M1. If the small heat exchange temperature difference change rate A is less than or equal to the small heat exchange temperature difference change rate target value M1, continue to execute the subsequent sub-steps of step S1; otherwise, determine the increased opening adjustment amount and response time of the flow control valve according to the small heat exchange temperature difference change rate A, stop executing the subsequent sub-steps of step S1 and go to step S2.

4. The method for regulating the flow rate of refrigerant in a refrigeration system (100) according to claim 2, characterized in that: In step S1.2, the following sub-steps are performed: S1.2.1 (408, 410): Obtain the pressure drop ΔP of the subcooler (105), and determine whether the pressure drop ΔP of the subcooler (105) is within the pressure drop target range [M3-ΔM3, M3+ΔM3]. If the pressure drop ΔP is within the pressure drop target range [M3-ΔM3, M3+ΔM3], go to step S1.9; otherwise, go to step S1.2.

2. S1.2.2 (422, 422.0, 422.1, 422.2): Determine whether the pressure drop ΔP is greater than the maximum value M3+ΔM3 in the pressure drop target interval [M3-ΔM3, M3+ΔM3]. If the pressure drop ΔP is greater than the maximum value M3+ΔM3, determine the reduced opening adjustment amount and response time of the flow control valve based on the pressure drop ΔP being greater than the maximum value M3+ΔM3, and go to step S2 (340, 342). Otherwise, determine the increased opening adjustment amount and response time of the flow control valve based on the pressure drop ΔP being less than the minimum value M3-ΔM3 in the pressure drop target interval [M3-ΔM3, M3+ΔM3], and go to step S2 (340, 342). Wherein, M3 is the pressure drop target value, and ΔM3 is the pressure drop hysteresis threshold.

5. The method for regulating the flow rate of refrigerant in a refrigeration system (100) according to claim 2, characterized in that: In step S1.2, the following steps (508, 510, 522) are performed: Get the outlet temperature T of the subcooler (105) subc.out and subcooler outlet pressure P subc.out The saturation temperature T liq.sat , and judge the outlet temperature T of the subcooler (105) subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat Is the difference less than zero? If the outlet temperature T subc.out and the subcooler outlet pressure P subc.out The saturation temperature T liq.sat If the difference is less than zero, continue to execute the subsequent sub-steps of step S1; Otherwise, according to the outlet temperature T subc.out and subcooler outlet pressure P subc.out The saturation temperature T liq.sat Determine the reduced opening adjustment amount and response time of the flow control valve, and go to step S2 (340, 342).

6. The method for regulating the flow rate of refrigerant in a refrigeration system (100) according to claim 2, characterized in that: In step S1.2, the following sub-steps are performed: S1.2.1(608): Obtain the subcooling degree T of the subcooler (105) subcooling , subcooling change rate C and pressure drop ΔP; S1.2.2-1(640): Determine the degree of supercooling T subcooling Is it within the first subcooling preset range? If the subcooling T subcooling If it is within the first subcooling preset range, go to step S1.9; otherwise, go to step S1.2.2-2; S1.2.2-2(642): Determine the degree of supercooling T subcooling Is it within the second subcooling preset range? If the subcooling T subcooling If it is within the second subcooling preset range, go to step S1.2.3-1; otherwise, go to step S1.2.3-2; S1.2.3-1 (644, 654): Determine whether the pressure drop ΔP is within the first pressure drop preset range. If the pressure drop ΔP is within the first pressure drop preset range, go to step S1.2.4; Otherwise, determine the reduced opening adjustment amount and response time of the flow control valve, and go to step S2 (340, 342); S1.2.3-2 (648, 650, 652): Determine whether the pressure drop ΔP is within a second preset pressure drop range. If the pressure drop ΔP is within the second preset pressure drop range, determine an increase in the opening adjustment amount and a response time of the flow control valve, and proceed to step S2 (340, 342). Otherwise, determine a decrease in the opening adjustment amount and a response time of the flow control valve, and proceed to step S2 (340, 342). S1.2.4 (646, 656): Determine whether the subcooling change rate C is within the preset subcooling change rate range. If so, proceed to step S1.9; otherwise, determine the reduced opening adjustment amount and response time of the flow control valve, and proceed to step S2 (340, 342). Among them, the first supercooling preset range is the supercooling target range [T target-sub -ΔT sub , T target-sub +ΔT sub ], the second subcooling preset range is smaller than the subcooling target range [T target-sub -ΔT sub , T target-sub +ΔT sub The minimum value T in ] target-sub -ΔT sub , the first pressure drop preset range is less than M3-ΔM3, the second pressure drop preset range is less than or equal to M3+ΔM3, and the subcooling change rate preset range is less than or equal to the subcooling change rate target value M4; and Among them, T target-sub is the target value of subcooling, ΔT sub is the subcooling hysteresis threshold, M3 is the pressure drop target value, and ΔM3 is the pressure drop hysteresis threshold.

7. The method for regulating the flow rate of refrigerant in a refrigeration system (100) according to claim 3, characterized in that: In step S1.2, the following steps are performed (708, 710, 722): Obtaining the pressure drop ΔP of the subcooler (105), and determining whether the pressure drop ΔP is less than or equal to the pressure drop target value M3; if the pressure drop ΔP is less than or equal to the pressure drop target value M3, proceeding to step S1.3; Otherwise, the reduced opening adjustment amount and response time of the flow control valve are determined according to the pressure drop ΔP, and the process goes to step S2 ( 340 , 342 ).

8. The method according to claim 1, wherein: The parameters of the refrigeration system are obtained based on the pressure detected by the pressure detection device and / or the temperature detected by the temperature detection device.

9. The method according to any one of claims 1 to 8, wherein: The subcooler (105) is arranged in the condenser (102).

10. A refrigeration system (100), characterized in that: The refrigeration system (100) comprises: compressor (101); Condenser (102); subcooler (105); Flow control valve (103); an evaporator (104), wherein the compressor (101), the condenser (102), the flow regulating valve (103) and the evaporator (104) are connected in sequence; a plurality of detection devices (111, 112, 113, 114, 115, 116, 117), the plurality of detection devices being configured to detect pressure and / or temperature of at least two components of the refrigeration system (100); and A control device (106), comprising a processor (107), the control device (106) being configured to execute the method according to any one of claims 1 to 9.

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