Control method of refrigeration system, refrigeration system and test equipment

Abstract

This application relates to a control method, a refrigeration system, and testing equipment for a refrigeration system. The control method includes acquiring the current superheat and lower limit value of the compressor; determining whether the refrigeration system meets a superheat adjustment condition based on the current superheat and the lower limit value, wherein the superheat adjustment condition characterizes the liquid carryover during compressor return gas; if the refrigeration system meets the superheat adjustment condition, it enters a control mode, which includes a main throttling device control mode and a regulating valve control mode. The technical solution of this application, when it is determined that the compressor returns with liquid carryover, reduces the liquid refrigerant content entering the compressor by adjusting the opening of the main throttling device in the circulation loop and the opening of the regulating valve in the cooling flow path. This significantly improves the liquid carryover effect during compressor return gas, helps reduce the risk of compressor damage due to liquid slugging, and extends the compressor's service life.

Description

Technical Field

[0001] This application relates to the field of refrigeration technology, and in particular to control methods for refrigeration systems, refrigeration systems, and testing equipment. Background Technology

[0002] Chip testing is a crucial step in the chip manufacturing process, aiming to reduce early potential failure rates. Chip testing equipment is typically equipped with a cooling system to create the appropriate testing temperature environment. The testing temperature of chip testing equipment is usually set within the range of -55℃ to 150℃. When the heat load decreases, the liquid refrigerant in the cooling system cannot evaporate sufficiently, easily leading to liquid carryover during gas return. This causes a large amount of liquid refrigerant to enter the compressor and participate in compression, which can damage the compressor and reduce its lifespan over time.

[0003] To prevent liquid carryover in the compressor return gas, the industry commonly adds a gas-liquid separator to the refrigeration system. When the two-phase refrigerant returns through the gas-liquid separator, it separates the gaseous refrigerant from the liquid refrigerant and lubricating oil. The liquid refrigerant and lubricating oil settle at the bottom, while the lubricating oil flows back to the compressor through the oil return port of the gas-liquid separator. If the system continuously carries liquid, the liquid refrigerant can easily fill the gas-liquid separator, causing it to fail. Moreover, when the refrigerant density is greater than that of the lubricating oil, the lubricating oil will still carry liquid refrigerant back into the compressor when returning from the gas-liquid separator. Summary of the Invention

[0004] Therefore, it is necessary to provide a control method, a refrigeration system, and testing equipment for a refrigeration system to address the problem of reduced compressor lifespan caused by liquid refrigerant entering the compressor.

[0005] In a first aspect, this application provides a control method for a refrigeration system, the refrigeration system comprising a compressor, a condenser, a main throttling device and an evaporator connected in sequence to form a circulation loop, the condenser comprising a cooling flow path for circulating external coolant, and a regulating valve provided on the cooling flow path;

[0006] The control method includes:

[0007] Obtain the current superheat and lower limit of superheat of the compressor;

[0008] Based on the current superheat and the lower limit of superheat, it is determined whether the refrigeration system meets the superheat adjustment conditions, which are used to characterize the compressor's return gas carrying liquid.

[0009] If the refrigeration system meets the superheat adjustment condition, it enters the control mode, which includes the main throttling device control mode and the regulating valve control mode.

[0010] Specifically, in the main throttling device control mode, the opening degree of the main throttling device is reduced; in the regulating valve control mode, the opening degree of the regulating valve is reduced.

[0011] In some embodiments, if the refrigeration system meets the superheat adjustment condition, it enters a control mode, including:

[0012] If the refrigeration system meets the superheat adjustment condition, it enters the main throttling device control mode and determines whether the refrigeration system has reached the first critical condition. The first critical condition is used to characterize that the main throttling device is in a critical state that can be safely controlled.

[0013] If the refrigeration system does not reach the first critical condition and does not meet the superheat adjustment condition, then exit the main throttling device control mode;

[0014] If the refrigeration system reaches the first critical condition and satisfies the superheat adjustment condition, it exits the main throttling device control mode and enters the regulating valve control mode.

[0015] In some embodiments, reducing the opening of the main throttling element includes:

[0016] Obtain pressure range information, which is obtained by equally dividing the pressure range formed by the maximum return gas pressure and the minimum return gas pressure of the compressor, and obtaining multiple pressure ranges sorted in order of range value size.

[0017] Obtain the current return gas pressure of the compressor, and determine the pressure range in which the current return gas pressure is located as the reference range from the pressure range information based on the current return gas pressure;

[0018] The target interval is determined based on the control interval and the pressure interval information; the target interval is the pressure interval whose interval value is less than the control interval and whose arrangement order is adjacent to the control interval;

[0019] A target pressure value is determined based on the target range, wherein the target pressure value belongs to the target range; a first opening reduction is determined based on the target pressure value and a first preset calculation rule.

[0020] The current opening of the main throttling device is reduced based on the first opening reduction.

[0021] In some embodiments, before determining the target range based on the control range and the pressure range information, the method further includes:

[0022] Determine whether the control interval is the lower limit interval; the lower limit interval is the pressure interval with the smallest interval value.

[0023] If so, it is determined that the refrigeration system has reached the first critical condition, and the main throttling device control mode is exited.

[0024] If not, then proceed as follows: Determine the target interval based on the control interval and the pressure interval information.

[0025] In some embodiments, after reducing the current opening of the main throttling element according to the first opening reduction, the method further includes:

[0026] The current opening degree of the main throttling element after adjustment is used to control the first working duration of the main throttling element;

[0027] If the refrigeration system meets the superheat adjustment condition, then return to the execution: obtain the current return gas pressure of the compressor, and determine the pressure range in which the current return gas pressure is located as the control range from the pressure range information based on the current return gas pressure.

[0028] In some embodiments, reducing the opening of the regulating valve includes:

[0029] Obtain the target exhaust superheat;

[0030] Obtain the current discharge superheat of the compressor;

[0031] The second opening reduction is determined based on the difference between the target exhaust superheat and the current exhaust superheat, and based on the second preset calculation rule.

[0032] The current opening of the regulating valve is reduced by the second opening amount.

[0033] In some embodiments, after reducing the current opening of the regulating valve by the second opening reduction, the method further includes:

[0034] The second duration of operation of the regulating valve is controlled by the current opening degree of the regulating valve after adjustment.

[0035] If the refrigeration system meets the superheat adjustment condition and does not reach the second critical condition, then return to the previous step: obtain the current discharge superheat of the compressor;

[0036] The second critical condition is used to characterize that the regulating valve is in a critical state that can be safely controlled, including at least one of the following: the current opening degree of the regulating valve is lower than the lower limit of the regulating valve opening degree, the current discharge pressure of the compressor is higher than the upper limit of the discharge pressure, and the current discharge superheat of the compressor is higher than the upper limit of the discharge superheat.

[0037] In some embodiments, if the refrigeration system reaches the first critical condition and satisfies the superheat adjustment condition, it exits the main throttling device control mode and enters the regulating valve control mode, further comprising:

[0038] If the refrigeration system reaches the second critical condition and meets the superheat adjustment condition, it exits the regulating valve control mode and enters the refrigerant temperature control mode until the refrigeration system no longer meets the superheat adjustment condition; in the refrigerant temperature control mode, the refrigeration system is controlled to raise the return gas temperature of the compressor.

[0039] In some embodiments, the circulation loop includes a main return gas path located between the outlet side of the evaporator and the compressor, and the refrigeration system includes a return gas bypass connected in parallel with the main return gas path. A regenerator is provided on the return gas bypass, and the regenerator has a regenerative flow path for heating the return gas bypass. A first control valve is provided on the return gas bypass located between the regenerator and the evaporator, and a second control valve is provided on the main return gas path. The regenerative flow path is formed by a flow path located between the compressor and the condenser in the circulation loop, or the regenerative flow path is formed by a cooling flow path, and the coolant in the cooling flow path flows upward, and the regenerator is located downstream of the condenser. Controlling the refrigeration system to raise the return gas temperature of the compressor includes: opening the first control valve and closing the second control valve.

[0040] In some embodiments, the refrigeration system includes a throttling bypass connected to the inlet side of the condenser and the outlet side of the main throttling element, and a secondary throttling element is provided on the throttling bypass; controlling the refrigeration system to increase the return gas temperature of the compressor includes: opening the secondary throttling element.

[0041] Secondly, this application provides a refrigeration system, including a compressor, a condenser, a main throttling device, and an evaporator connected in sequence to form a circulation loop. The condenser includes a cooling flow path for circulating external coolant, and a regulating valve is provided on the cooling flow path. The refrigeration system is capable of performing the control method as described in any of the above embodiments.

[0042] Thirdly, this application provides a testing device, including a testing terminal and a cooling system as described in the above embodiments, wherein the cooling system is used to adjust the temperature of the testing terminal.

[0043] The control method, refrigeration system, and testing equipment described above determine whether the compressor is carrying liquid back into the gas flow by measuring the compressor's superheat. When liquid back into the gas flow is detected, the liquid refrigerant content entering the compressor is reduced by adjusting the opening of the main throttling device in the circulation loop and the opening of the regulating valve in the cooling flow path. This significantly improves the liquid back into the gas flow of the compressor, helps reduce the risk of compressor damage due to liquid slugging, and extends the compressor's service life. Attached Figure Description

[0044] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0045] Figure 1 This is a schematic diagram of a refrigeration system according to some embodiments.

[0046] Figure 2 This is a flowchart illustrating the control method of a refrigeration system according to some embodiments.

[0047] Figure 3 This is a flowchart illustrating the control method of a refrigeration system according to other embodiments.

[0048] Figure 4 This is a detailed flowchart of the step of lowering the opening degree of the main throttling element in the control method of a refrigeration system in some embodiments.

[0049] Figure 5 This is a detailed flowchart of adjusting the opening degree of the main throttling element in the control method of the refrigeration system in some other embodiments.

[0050] Figure 6 This is a detailed flowchart of adjusting the opening degree of the main throttling element in the control method of the refrigeration system in some other embodiments.

[0051] Figure 7 This is a detailed flowchart illustrating the process of adjusting the opening of a regulating valve in the control method of a refrigeration system according to some embodiments.

[0052] Figure 8 This is a detailed flowchart illustrating the process of adjusting the opening of the regulating valve in the control method of a refrigeration system in some other embodiments.

[0053] Figure 9 This is a flowchart illustrating the control method of a refrigeration system according to other embodiments.

[0054] Figure 10 This is a schematic diagram of the composition of a refrigeration system in some other embodiments.

[0055] Figure 11 This is a schematic diagram of the composition of a refrigeration system in some other embodiments.

[0056] Figure 12 This is a schematic diagram of the composition of a refrigeration system in some other embodiments.

[0057] The reference numerals in the detailed embodiments are as follows:

[0058] 100. Refrigeration system; 10. Compressor; 20. Condenser; L1. Cooling flow path; 21. Regulating valve; 30. Main throttling device; 40. Evaporator; 50. Gas-liquid separator; 60. Regenerator; L2. Regenerating flow path; 70. Secondary throttling device; f1. First control valve; f2. Second control valve; S. Circulation loop; S1. Main return gas path; H. Return gas bypass; J. Throttling bypass. Detailed Implementation

[0059] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0060] In the description of this application, it should be understood that, where they appear, the terms “center,” “longitudinal,” “lateral,” “length,” “width,” “thickness,” “upper,” “lower,” “front,” “rear,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” “outer,” “clockwise,” “counterclockwise,” “axial,” “radial,” and “circumferential” indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0061] Furthermore, where applicable, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0062] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," "fixing," etc., shall be interpreted broadly. For example, they may refer to a fixed connection, a detachable connection, or an integral part; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; they may refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0063] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0064] It should be noted that, if an element is described as "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is described as "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0065] In response to the problems mentioned in the background art, embodiments of this application provide a control method for a refrigeration system, a refrigeration system, and a testing device.

[0066] To facilitate understanding, the refrigeration system in the embodiments of this application will be introduced first.

[0067] Figure 1 This is a system schematic diagram of a refrigeration system 100 according to some embodiments. (Refer to...) Figure 1 The refrigeration system 100 in this embodiment includes a compressor 10, a condenser 20, a main throttling device 30 and an evaporator 40 connected in sequence to form a circulation loop S. The condenser 20 includes a cooling flow path L1 for the flow of external coolant, and a regulating valve 21 is provided on the cooling flow path L1.

[0068] When the refrigeration system 100 is cooling, the compressor 10 discharges high-temperature and high-pressure gaseous refrigerant from its exhaust end. The high-temperature and high-pressure gaseous refrigerant exchanges heat with the coolant flowing in the cooling flow path L1 at the condenser 20 and is cooled down. Then, it flows through the main throttling device 30 and is cooled down and throttled, becoming a low-temperature and low-pressure liquid refrigerant. The low-temperature and low-pressure liquid refrigerant cools the external heat load at the evaporator 40 and becomes a low-temperature and low-pressure gaseous refrigerant. Finally, it flows back to the return end of the compressor 10 and is compressed again to form a high-temperature and high-pressure gaseous refrigerant. This cycle continues.

[0069] The coolant can be cooling water or fluorinated liquid, etc. The regulating valve 21 is installed on the cooling flow path L1 to regulate the flow rate of the coolant in the cooling flow path L1, thereby regulating the degree of condensation of the refrigerant by the condenser 20.

[0070] In other embodiments, the refrigeration system 100 may also include a gas-liquid separator 50, which is disposed on the circulation loop S and connected to the return gas end of the compressor 10. Regarding other configuration information of the refrigeration system 100, those skilled in the art can perform conventional designs to improve the operational stability of the refrigeration system 100, such as installing an oil separator on the discharge side of the compressor 10. For the specific selection of devices such as the compressor 10, condenser 20, main throttling device 30, and evaporator 40, please refer to conventional selections in the art; no limitations are made here. It should be noted that the main throttling device 30 and the secondary throttling device 70 mentioned below in the embodiments of this application can be conventional components in the refrigeration field, such as conventional throttling valves, expansion valves, and expansion throttling valves.

[0071] Based on the refrigeration system 100 in the above embodiments, the control method of the refrigeration system proposed in the embodiments of this application will be described in detail below.

[0072] Figure 2 This is a schematic flowchart illustrating the control method of a refrigeration system according to some embodiments. (Refer to...) Figure 2 The control method for a refrigeration system provided in this application includes:

[0073] S1. Obtain the current superheat and lower limit of superheat of compressor 10;

[0074] Appropriate superheat can prevent liquid carryover in the return gas of compressor 10. The current superheat of compressor 10 can be either the current discharge superheat or the current return gas superheat. Discharge temperature and discharge pressure sensors can be installed on the discharge pipe of compressor 10 to detect the discharge superheat. Specifically, the temperature value detected by the discharge temperature sensor is recorded as W1, and the pressure value detected by the discharge pressure sensor is recorded as P1. Based on the correspondence between refrigerant saturation temperature and saturation pressure, the saturation temperature w1 corresponding to pressure P1 is determined. The difference between W1 and w1 can then be determined as the discharge superheat.

[0075] Similarly, a return gas temperature sensor and a return gas pressure sensor can be installed on the return gas pipe of compressor 10 to detect the return gas superheat. Specifically, the temperature value detected by the return gas temperature sensor is recorded as W2, and the pressure value detected by the return gas pressure sensor is recorded as P2. Based on the correspondence between refrigerant saturation temperature and saturation pressure, the saturation temperature w2 corresponding to the pressure value P2 is determined. The difference between W2 and w2 can then be determined as the return gas superheat.

[0076] If the current superheat is exhaust superheat, the lower limit of superheat is the lower limit of exhaust superheat. For example, the lower limit of exhaust superheat can be set to 25°C. If the current superheat is return gas superheat, the lower limit of superheat is the lower limit of return gas superheat. For example, the lower limit of return gas superheat can be set to 5°C.

[0077] S2. Based on the current superheat and the lower limit of superheat, determine whether the refrigeration system 100 meets the superheat regulation conditions. The superheat regulation conditions are used to characterize the return gas and liquid carryover of the compressor 10.

[0078] Specifically, if the current superheat is not lower than the lower limit of superheat, it means that the compressor 10 returns gas without liquid, and the refrigeration system 100 does not meet the superheat regulation conditions. If the current superheat is lower than the lower limit of superheat, it means that the compressor 10 returns gas with liquid, and the refrigeration system 100 meets the superheat regulation conditions.

[0079] S3. If the refrigeration system 100 meets the superheat regulation conditions, it enters the control mode. The control mode includes the main throttling device control mode and the regulating valve control mode. In the main throttling device control mode, the opening of the main throttling device 30 is reduced. In the regulating valve control mode, the opening of the regulating valve 21 is reduced.

[0080] When compressor 10 experiences liquid carryover in the return gas, this can be improved by adjusting the opening of the main throttling device 30 and the opening of the regulating valve 21. Adjusting the opening of the main throttling device 30 regulates the refrigerant flow rate in the circulation loop S. Normally, lowering the opening of the main throttling device 30 reduces the flow rate of liquid refrigerant formed after throttling and cooling by the main throttling device 30, thus reducing the amount of liquid refrigerant entering the evaporator 40. This, in turn, reduces the amount of liquid refrigerant returning to compressor 10, improving the liquid carryover in compressor 10's return gas.

[0081] Adjusting the opening of regulating valve 21 changes the flow rate of coolant in cooling path L1, thereby adjusting the heat exchange capacity of condenser 20. When the opening of regulating valve 21 is reduced, the flow rate of coolant in cooling path L1 decreases, the heat exchange efficiency of condenser 20 for the high-temperature, high-pressure gaseous refrigerant discharged from compressor 10 decreases, the temperature of the refrigerant flowing out of condenser 20 increases, and the content of gaseous refrigerant increases while the content of liquid refrigerant decreases in the refrigerant after being throttled and cooled by self-throttling device 30. This reduces the amount of liquid refrigerant entering evaporator 40, thereby reducing the amount of liquid refrigerant returning to compressor 10 and improving the liquid carryover effect of compressor 10.

[0082] In this embodiment, the superheat of the compressor 10 is used to determine whether the compressor 10 is carrying liquid back into the gas. When it is determined that the compressor 10 is carrying liquid back into the gas, the liquid refrigerant content entering the compressor 10 is reduced by two fine-tuning methods: lowering the opening of the main throttling device 30 on the circulation loop S and lowering the opening of the regulating valve 21 on the cooling flow path L1. This has a significant effect on improving the liquid back into the gas of the compressor 10, which helps to reduce the risk of the compressor 10 being damaged by liquid slugging and extends the service life of the compressor 10.

[0083] In an optional embodiment, step S1 specifically includes: acquiring the current superheat of compressor 10 at preset time intervals; correspondingly, step S2 specifically includes: if the current superheat acquired N times consecutively is lower than the lower limit of superheat, then it is determined that the refrigeration system 100 meets the superheat adjustment condition, where N is an integer greater than 1.

[0084] N can take values ​​of 2, 3, etc. The preset time can be 30s, 60s, 90s, 120s, etc. In practical applications, under normal operating conditions, the refrigeration system 100 acquires the current superheat of the compressor 10 at preset intervals. If the current superheat acquired multiple times consecutively is lower than the lower limit of superheat, it indicates that the compressor 10 has a liquid carryover problem. Thus, when the compressor 10 temporarily experiences liquid carryover due to short-term changes in heat load, superheat adjustment is unnecessary, reducing program waste and helping to maintain the operational stability of the refrigeration system 100.

[0085] Figure 3 This is a flowchart illustrating the control method of a refrigeration system according to other embodiments. Figure 2 Compared to the illustrated embodiment, the difference lies in that, if the refrigeration system 100 meets the superheat regulation conditions, step S3, which involves entering the control mode, includes:

[0086] S301. If the refrigeration system 100 meets the superheat regulation condition, it enters the main throttling device control mode and determines whether the refrigeration system 100 has reached the first critical condition. The first critical condition is used to characterize that the main throttling device 30 is in a critical state that can be safely controlled.

[0087] In the main throttling device control mode, the opening degree of the main throttling device 30 is reduced to decrease the amount of liquid refrigerant entering the evaporator 40, thereby improving the liquid carryover effect of the compressor 10. To ensure the normal circulation of refrigerant in the circulation loop S and the normal cooling capacity of the refrigeration system 100, the opening degree of the main throttling device 30 cannot be reduced indefinitely during the operation of the refrigeration system 100. A first critical condition is used to limit the minimum opening degree of the main throttling device 30. When the refrigeration system 100 reaches the first critical condition, the main throttling device 30 is in a safely controllable critical state. When the refrigeration system 100 has not reached the first critical condition, reducing the opening degree of the main throttling device 30 has little impact on the normal operation of the refrigeration system 100. When the refrigeration system 100 reaches the first critical condition, continuing to reduce the opening degree of the main throttling device 30 may adversely affect the normal operation of the refrigeration system 100; therefore, it is necessary to set a first critical condition to control the minimum opening degree of the main throttling device 30. In one example, the first critical condition is set so that the opening of the main throttling element 30 reaches its lower limit.

[0088] S302. If the refrigeration system 100 does not reach the first critical condition and does not meet the superheat regulation condition, then exit the main throttling device control mode.

[0089] In the main throttling device control mode, if the refrigeration system 100 does not meet the superheat regulation conditions and the refrigeration system 100 does not reach the first critical condition during the process of lowering the opening of the main throttling device 30, it means that when the main throttling device 30 lowers its opening value within the safe control range, the current superheat reaches or exceeds the lower limit of superheat, and the compressor 10 returns gas without liquid. Then, the main throttling device control mode is exited, thus solving the problem of liquid return gas of the compressor 10.

[0090] S303. If the refrigeration system 100 reaches the first critical condition and meets the superheat regulation condition, it exits the main throttling device control mode and enters the regulating valve control mode.

[0091] In the main throttling device control mode, if the refrigeration system 100 reaches the first critical condition during the process of lowering the opening of the main throttling device 30, the main throttling device 30 cannot be lowered further to avoid adverse effects on the operation of the refrigeration system 100. At the same time, if the refrigeration system 100 still meets the superheat regulation condition, that is, if the compressor 10 is still carrying liquid in the return gas, then the main throttling device control mode is exited and the regulating valve control mode is entered.

[0092] In other words, when the problem of liquid carryover in the return gas of the compressor 10 cannot be completely solved by adjusting the main throttling device 30, when the refrigeration system 100 reaches the first critical condition (such as when the opening of the main throttling device 30 is lowered to its lower limit value, the regulating valve 21 is activated to regulate the heat exchange capacity of the condenser 20, so as to further improve the problem of liquid carryover in the return gas of the compressor 10).

[0093] Because the main throttling device 30 is located on the circulation loop S, it can directly regulate the liquid refrigerant content entering the evaporator 40. When adjusting its opening, the regulation result can quickly and effectively improve the liquid carryover problem of the compressor 10, and the solution speed is faster. Because the regulating valve 21 is located on the cooling flow path L1, it indirectly regulates the liquid refrigerant content entering the evaporator 40 by adjusting the flow rate of the coolant. When adjusting its opening, the effect of its regulation result on the liquid carryover problem of the compressor 10 is relatively slow, and the improvement effect is generally average.

[0094] In this embodiment, when the refrigeration system 100 meets the superheat regulation conditions, it first enters the main throttling device control mode. By adjusting the opening of the main throttling device 30, the problem of liquid carryover in the return gas of the compressor 10 can be effectively and quickly improved. When adjusting the opening of the main throttling device 30 cannot completely solve the problem of liquid carryover in the return gas, the regulating valve 21 is activated to assist in improving the problem of liquid carryover in the return gas of the compressor 10. In this way, the problem of liquid carryover in the return gas of the compressor 10 can be improved more quickly and effectively without affecting the normal operation of the refrigeration system 100. Moreover, the main throttling device control mode and the regulating valve control mode are performed sequentially, which not only simplifies the control but also reduces system oscillation.

[0095] Of course, in other embodiments, when the refrigeration system 100 meets the superheat regulation conditions, it can simultaneously enter the main throttling device control mode and the regulating valve control mode, or enter the regulating valve control mode first and then the main throttling device control mode.

[0096] Figure 4 This is a detailed flowchart illustrating the step of reducing the opening degree of the main throttling element 30 in the control method of a refrigeration system according to some embodiments. (Refer to...) Figure 4 In some embodiments, the step of reducing the opening degree of the main throttling element 30 includes:

[0097] S311. Obtain pressure range information. The pressure range information is obtained by equally dividing the pressure range formed by the maximum return gas pressure and the minimum return gas pressure of the compressor 10, and obtaining multiple pressure ranges that are sorted in order of the range value.

[0098] The return gas pressure refers to the pressure of the refrigerant in the return gas pipe connecting the compressor 10 and the evaporator 40. This pressure can be obtained by installing a pressure sensor at the return gas pipe. The magnitude of the return gas pressure affects the operating performance and energy consumption of the compressor 10. Excessive return gas pressure increases the load on the compressor 10 and reduces its efficiency. Insufficient return gas pressure reduces the compressor 10's discharge capacity, resulting in energy waste. Therefore, it is generally required that the return gas pressure of the compressor 10 be within a reasonable range during operation. This pressure range is defined by the maximum and minimum return gas pressures. Both the maximum and minimum return gas pressures are set values, which can be specifically set according to the type of compressor 10.

[0099] The pressure range defined by the maximum and minimum return gas pressures is divided equally to obtain pressure interval information. This pressure interval information includes multiple pressure intervals and their sorting by interval value. The pressure intervals are sorted either from smallest to largest or largest to smallest.

[0100] For example, if the maximum return gas pressure is set to 500 kPa and the minimum return gas pressure is set to 100 kPa, then the pressure range is [100 kPa, 500 kPa]. Dividing this range into equal 50 kPa intervals, we get eight pressure intervals ordered from smallest to largest: [100 kPa, 150 kPa), [150 kPa, 200 kPa), [200 kPa, 250 kPa), [250 kPa, 300 kPa), [300 kPa, 350 kPa), [350 kPa, 400 kPa), [400 kPa, 450 kPa), and [450 kPa, 500 kPa]. The pressure interval information includes the interval values ​​and the order information for these eight pressure intervals.

[0101] S312. Obtain the current return gas pressure of compressor 10, and determine the pressure range where the current return gas pressure is located as the reference range based on the pressure range information.

[0102] Following the example above, if the current return gas pressure of compressor 10 is 215 kPa, and its value falls within the pressure range of [200 kPa, 250 kPa), then the range of [200 kPa, 250 kPa) will be used as the reference range.

[0103] S313. Determine the target interval based on the control interval and pressure interval information; the target interval is the pressure interval whose interval value is less than the control interval and whose arrangement order is adjacent to the control interval;

[0104] Continuing with the example above, after determining the control interval as [200 kPa, 250 kPa), the pressure intervals that are adjacent to [200 kPa, 250 kPa) and whose interval values ​​are less than [200 kPa, 250 kPa) are taken as the target intervals. In this example, the target interval is [150 kPa, 200 kPa).

[0105] S314. Determine the target pressure value based on the target range, where the target pressure value belongs to the target range; determine the first opening reduction based on the target pressure value and the first preset calculation rule.

[0106] The target pressure value is a pressure value located within the target range. The pressure value can be selected as the lower limit, median, or upper limit of the target range, and can be set based on experience or experimental results. For example, if the pressure value is set as the lower limit of the target range (150 kPa, 200 kPa), then the pressure value can be determined as 150 kPa.

[0107] After determining the target pressure value, the first opening reduction is determined based on the target pressure value and the first preset calculation rule. The technicians can determine the first preset calculation rule based on a reasonable design, and the specific calculation method is not limited here. For example, the design of the first preset calculation rule is to use the target pressure value as the objective, perform PID calculations, use the difference between the current return air pressure and the target pressure value as the input variable, and use the output result as the first opening reduction.

[0108] S315. Adjust the current opening of the main throttling element 30 according to the first opening reduction.

[0109] After reducing the current opening of the main throttling device 30 by the first reduction, the current return gas pressure of the compressor 10 can be made to approach the target pressure value. Typically, the first reduction is a percentage; for example, if the first reduction is 10%, then the current opening is reduced by 10%.

[0110] As can be seen from the calculation method of superheat, the magnitude of the return gas pressure directly affects the magnitude of the return gas superheat of the compressor 10. In this embodiment, by dividing the allowable pressure range of the return gas pressure during compressor 10 operation into multiple pressure intervals, and determining the target interval based on the reference interval where the current return gas pressure is located, the opening degree of the main throttling device 30 is adjusted using the target pressure value corresponding to the target interval as the target, making the adjustment result of the main throttling device 30 more effective.

[0111] Figure 5 This is a detailed flowchart illustrating the reduction of the opening degree of the main throttling element 30 in the control method of a refrigeration system in some other embodiments. Figure 4 Compared to the illustrated embodiment, the difference lies in that, before step S313 of determining the target range based on the control range and pressure range information, the following step is further included:

[0112] S316. Determine whether the control interval is the lower limit interval; the lower limit interval is the pressure interval with the smallest interval value.

[0113] S317. If so, it is determined that the refrigeration system 100 has reached the first critical condition and exits the main throttling device control mode.

[0114] If not, then execute S313: Determine the target range based on the control range and pressure range information.

[0115] The lower limit range is the smallest value among multiple pressure ranges. In the example above, the lower limit range is [100 kPa, 150 kPa). When the reference range is the lower limit range, it indicates that the current return gas pressure of compressor 10 is within the lower limit range, the target range does not exist, and therefore the target pressure value and the first opening reduction cannot be determined. It is then determined that the refrigeration system 100 has reached the first critical condition, and the main throttling device control mode is exited to maintain the operational stability of the refrigeration system 100. When the reference range is not the lower limit range, step S313 is executed to determine the target range, target pressure value, and first opening reduction, and the opening of the main throttling device 30 is reduced.

[0116] In this way, when the current return gas pressure of compressor 10 is in the lower limit range, the main throttling device 30 can be stopped to control, so as to prevent compressor 10 from operating below the lower limit return gas pressure and ensure that compressor 10 is in normal operating condition.

[0117] Figure 6 This is a detailed flowchart illustrating the reduction of the opening degree of the main throttling element 30 in the control method of a refrigeration system in some other embodiments. Figure 5 Compared to the illustrated embodiment, the difference lies in that, after step S315 of reducing the current opening of the main throttling element 30 according to the first opening reduction, the following is also included:

[0118] S318. The first working duration of the main throttling device 30 is controlled by the current opening degree of the adjusted main throttling device 30.

[0119] S319. If the refrigeration system 100 meets the superheat regulation conditions, then return to execute S312: obtain the current return gas pressure of the compressor 10, and determine the pressure range where the current return gas pressure is located as the reference range based on the pressure range information.

[0120] In this embodiment, each time the opening of the main throttling element 30 is reduced, it is maintained for a first duration (e.g., 1 min, 2 min, 3 min, 4 min, 5 min) to allow the refrigeration system 100 to operate stably. After this, the system is reassessed to determine whether it meets the superheat regulation conditions, resulting in a more accurate assessment. If the conditions are met, it indicates that the regulation is inadequate, and the process returns to step S312 to continue reducing the opening of the main throttling element 30.

[0121] Thus, when the compressor 10 returns liquid and the main throttling device 30 is within a safe control range, the opening of the main throttling device 30 can be gradually reduced multiple times, making the adjustment process more stable and more conducive to the operational stability of the refrigeration system 100.

[0122] Understandably, after step S318, the method further includes: if the refrigeration system 100 does not meet the superheat regulation conditions, then the main throttling device control mode is exited. That is, when the liquid carryover in the return gas of the compressor 10 is resolved by adjusting the opening of the main throttling device 30 within the safe control range, the main throttling device control mode is exited.

[0123] Figure 7 This is a detailed flowchart illustrating the process of adjusting the opening of regulating valve 21 in the control method of a refrigeration system according to some embodiments. (Refer to...) Figure 7 In some embodiments, the step of reducing the opening of the regulating valve 21 includes:

[0124] S321. Obtain the target exhaust superheat.

[0125] The target exhaust superheat is a preset value. The target exhaust superheat can be the lower limit of exhaust superheat or other set values ​​that exceed the lower limit of exhaust superheat.

[0126] S322, Obtain the current exhaust superheat of compressor 10;

[0127] The current exhaust superheat of compressor 10 can be obtained using the scheme described in the above embodiments, and will not be repeated here.

[0128] S323. Determine the second opening reduction based on the difference between the target exhaust superheat and the current exhaust superheat, and based on the second preset calculation rule;

[0129] Specifically, the second preset calculation rule can be based on the difference between the target exhaust superheat and the current exhaust superheat, and the second opening reduction can be calculated based on the PID control logic. The specific design of the PID control logic can be set conventionally and is not specifically limited here.

[0130] S324. Reduce the current opening of regulating valve 21 by the second opening degree.

[0131] Typically, the second opening reduction is a percentage. For example, if the second opening reduction is 10%, then the opening of the regulating valve 21 can be reduced by 10% based on the current opening.

[0132] There is a negative correlation between the discharge superheat of compressor 10 and the opening of regulating valve 21; the smaller the opening of regulating valve 21, the higher the discharge superheat. Therefore, the discharge superheat of compressor 10 can reflect whether compressor 10 is carrying liquid back into the gas. The opening of regulating valve 21 can be controlled by adjusting the discharge superheat, resulting in a direct and reliable control.

[0133] Figure 8 This is a detailed flowchart illustrating the process of adjusting the opening of regulating valve 21 in the control method of a refrigeration system according to other embodiments. Figure 7 Compared to the illustrated embodiment, the difference lies in that, after step S324 of reducing the current opening of the regulating valve 21 by a second opening degree, the following is further included:

[0134] S325, control the second duration of operation of the regulating valve 21 by adjusting the current opening degree of the regulating valve 21 after adjustment;

[0135] S326. If the refrigeration system 100 meets the superheat adjustment condition and has not reached the second critical condition, then return to execute S322: obtain the current discharge superheat of the compressor 10;

[0136] The second critical condition is used to characterize that the regulating valve 21 is in a critical state that can be safely controlled, including at least one of the following: the current opening degree of the regulating valve 21 is lower than the lower limit of the opening degree of the regulating valve 21, the current discharge pressure of the compressor 10 is higher than the upper limit of the discharge pressure, and the current discharge superheat of the compressor 10 is higher than the upper limit of the discharge superheat.

[0137] In this embodiment, each time the opening of the regulating valve 21 is reduced, it is maintained for a second duration (e.g., 1 min, 2 min, 3 min, 4 min, 5 min) to allow the refrigeration system 100 to operate stably. Then, the refrigeration system 100 is re-evaluated to determine whether it meets the superheat regulation conditions and whether it has reached the second critical condition, resulting in a more accurate judgment.

[0138] The second critical condition can be that the opening of the regulating valve 21 reaches its lower limit, or that the current discharge pressure of the compressor 10 is higher than its upper limit, or that the current discharge superheat of the compressor 10 is higher than its upper limit. Excessively high discharge pressure and discharge superheat will adversely affect the operation of the compressor 10 and easily damage it. If the opening of the regulating valve 21 is too small, it will affect the cooling capacity of the refrigeration system 100 and hinder its normal operation. Therefore, when the refrigeration system 100 reaches the second critical condition, it indicates that the regulating valve 21 has reached a critical state where it can be safely controlled. If the regulating valve 21 is further lowered when the refrigeration system 100 reaches the second critical condition, it may have adverse consequences for the normal operation of the refrigeration system 100.

[0139] If the refrigeration system 100 does not meet the superheat regulation conditions, it means that the compressor 10 does not carry liquid back, indicating that the regulation is in place and the regulating valve control mode is exited.

[0140] When the refrigeration system 100 meets the superheat regulation condition and does not reach the second critical condition, it indicates that the regulating valve 21 is within the safe regulation range. If the problem of liquid carryover in the return gas of the compressor 10 is further improved by lowering the opening of the regulating valve 21, then the execution step S322 is returned to obtain the current discharge superheat of the compressor 10 again, and the second opening reduction is recalculated to continue to lower the opening of the regulating valve 21.

[0141] Thus, when the problem of liquid carryover in the return gas of the compressor 10 is solved within the safe control range of the regulating valve 21, the opening of the regulating valve 21 can be gradually reduced multiple times, making the adjustment process more stable and more conducive to the operational stability of the refrigeration system 100.

[0142] Figure 9 This is a flowchart illustrating the control method of a refrigeration system according to other embodiments. Figure 3 Compared to the illustrated embodiment, the difference lies in that, after step S303, whereby the refrigeration system 100 exits the main throttling device control mode and enters the regulating valve control mode if the refrigeration system 100 reaches the first critical condition and satisfies the superheat adjustment condition, the method further includes:

[0143] S4. If the refrigeration system 100 reaches the second critical condition and meets the superheat regulation condition, exit the regulating valve control mode and enter the refrigerant temperature control mode until the refrigeration system 100 no longer meets the superheat regulation condition; in the refrigerant temperature control mode, control the refrigeration system 100 to raise the return gas temperature of the compressor 10.

[0144] As shown above, when the refrigeration system 100 reaches the second critical condition, the opening of the regulating valve 21 cannot be further reduced, otherwise it will have adverse consequences for the stable operation of the refrigeration system 100. If the refrigeration system 100 still meets the superheat regulation condition at this time, it means that reducing the opening of the regulating valve 21 cannot solve the problem of liquid carryover in the return gas of the compressor 10. Therefore, it enters the refrigerant temperature control mode, and further improves the liquid carryover in the return gas of the compressor 10 by increasing the return gas temperature of the compressor 10.

[0145] The return gas temperature of compressor 10 refers to the temperature of the refrigerant flowing through the return gas pipe of compressor 10. The higher the return gas temperature of compressor 10, the less liquid refrigerant and the more gaseous refrigerant is in the return gas pipe. Increasing the return gas temperature of compressor 10 can improve the problem of liquid carryover in the return gas of compressor 10.

[0146] In practical applications, if the compressor 10 still carries liquid in the return gas after adjustment by the regulating valve 21, a common reason is that the refrigeration system 100 is in an abnormal operating state, such as when the heat load is removed. At this time, the refrigerant temperature control mode is entered, and the return gas temperature of the compressor 10 is increased to solve the problem of liquid carrying in the return gas of the compressor 10. This mode has a large adjustment range and can protect the refrigeration system 100 from shutdown.

[0147] To increase the return gas temperature of compressor 10, a heater can be installed at the return gas pipe to vaporize the liquid refrigerant inside the return gas pipe. Alternatively, the solution described in the following embodiments can be adopted.

[0148] Figures 10 to 12 This is a schematic diagram of the composition of a refrigeration system 100 in several other different embodiments.

[0149] Reference Figure 10 and Figure 11 In some embodiments, the circulation loop S includes a main return gas path S1 located between the outlet side of the evaporator 40 and the compressor 10. The refrigeration system 100 includes a return gas bypass H connected in parallel with the main return gas path S1. A regenerator 60 is installed on the return gas bypass H, and the regenerator 60 has a regenerative flow path L2 for heating the return gas bypass H. A first control valve f1 is installed on the return gas bypass H located between the regenerator 60 and the evaporator 40, and a second control valve f2 is installed on the main return gas path S1. The regenerative flow path L2 is formed by the flow path located between the compressor 10 and the condenser 20 in the circulation loop S, or the regenerative flow path L2 is formed by the cooling flow path L1, and the regenerator 60 is located downstream of the condenser 20 in the direction of coolant flow in the cooling flow path L1.

[0150] like Figure 10 As shown, the flow path between the compressor 10 and the condenser 20 is the regenerative flow path L2. When the high-temperature refrigerant discharged from the compressor 10 flows through the regenerator 60, it exchanges heat with the return gas bypass H to heat the refrigerant on the return gas bypass H, thereby increasing the return gas temperature of the compressor 10.

[0151] like Figure 11 As shown, the cooling flow path L1 of the condenser 20 serves as the regenerating flow path L2. The coolant on the cooling flow path L1 absorbs the high temperature of the refrigerant flowing through the condenser 20 and its temperature rises. Then, when it flows through the regenerator 60, it exchanges heat with the return gas bypass H to heat the refrigerant on the return gas bypass H, thereby increasing the return gas temperature of the compressor 10.

[0152] A first control valve f1 is installed on the return gas bypass H, and a second control valve f2 is installed on the return gas main S1. These two valves cannot be simultaneously activated. When entering refrigerant control mode, it is necessary to increase the return gas temperature, requiring the return gas refrigerant to return to the compressor 10 via the return gas bypass H. At this time, the second control valve f2 is closed, and the first control valve f1 is opened. When exiting refrigerant control mode, the first control valve f1 is closed, the second control valve f2 is opened, and the refrigeration system 100 operates normally.

[0153] In this embodiment, by setting a return gas bypass H in parallel with the return gas main S1, under the refrigerant temperature control mode, the return gas refrigerant flowing through the return gas bypass H can be heated by the regenerator 60 using the temperature of the high-temperature refrigerant in the circulation loop S or by using the heated coolant, directly vaporizing the liquid components in the return gas refrigerant. This not only efficiently solves the problem of liquid carrying in the return gas of the compressor 10, but also saves energy.

[0154] In some embodiments, based on the above-described structure of the refrigeration system 100, step S4, controlling the refrigeration system 100 to raise the return gas temperature of the compressor 10, includes: opening the first control valve f1 and closing the second control valve f2.

[0155] In this way, when the refrigerant flowing to the return gas end of the compressor 10 flows through the return gas bypass H, it can exchange heat with the reheat flow path L2 of the regenerator 60. The refrigerant flowing through the regenerator 60 heats the return gas refrigerant, vaporizes the liquid refrigerant in the return gas refrigerant, reduces the liquid refrigerant content returning to the compressor 10, and improves and solves the problem of liquid carryover in the return gas of the compressor 10.

[0156] Understandably, after the first control valve f1 is opened, if the refrigeration system 100 does not meet the superheat regulation conditions, that is, the compressor 10 does not return gas with liquid, then the first control valve f1 is closed and the second control valve f2 is switched from the closed state to the open state.

[0157] Reference Figure 12 In other embodiments, the refrigeration system 100 includes a throttling bypass J connected to the inlet side of the condenser 20 and the outlet side of the main throttling element 30, and a secondary throttling element 70 is provided on the throttling bypass J.

[0158] The inlet of the throttling bypass J is directly connected to the discharge end of the compressor 10. In the refrigerant temperature control mode, a portion of the high-temperature refrigerant discharged from the compressor 10 flows along the circulation loop S through the condenser 20 and the main throttling element 30 to obtain the first throttling refrigerant; the other portion of the high-temperature refrigerant is diverted to the throttling bypass J, and after being throttled and cooled by the secondary throttling element 70, it becomes the second throttling refrigerant. The temperature of the first throttling refrigerant is lower than that of the second throttling refrigerant, and the two mix in the evaporator 40, which increases the refrigerant dryness of the refrigerant entering the evaporator 40. The higher the refrigerant dryness, the higher the gaseous refrigerant content, and the lower the heat exchange between the evaporator 40 and the outside. The refrigerant temperature flowing out of the evaporator 40 is higher and the gaseous composition is higher, which can increase the return gas temperature of the compressor 10 and improve the liquid carryover in the return gas of the compressor 10.

[0159] Refrigerant dryness fraction refers to the weight proportion of gaseous refrigerant in a unit mass of refrigerant. It can be calculated from the inlet pressure and temperature of the refrigerant at the inlet side of the evaporator 40. A dryness fraction closer to 1 indicates a higher gaseous component of the refrigerant. In actual operation, the refrigeration system 100 can be judged to meet superheat regulation conditions by checking whether the refrigerant dryness fraction reaches the target value. The target value for refrigerant dryness fraction can be 1; specifically, when the inlet temperature exceeds the saturation temperature corresponding to the inlet pressure, the refrigerant dryness fraction reaches 1. Understandably, when the refrigerant dryness fraction reaches 1, the gaseous component of the refrigerant is 100%, no liquid refrigerant enters the evaporator 40, and no liquid refrigerant flows out of the evaporator 40, resulting in compressor 10 returning gas without liquid, and the refrigeration system 100 does not meet the superheat regulation conditions.

[0160] Of course, the target value for refrigerant dryness can also be other reasonable values, which can be set based on actual experience or experiments.

[0161] In some embodiments, based on the above-described structure of the refrigeration system 100, step S4, controlling the refrigeration system 100 to raise the return gas temperature of the compressor 10, includes: opening the secondary throttling device 70.

[0162] The high-temperature refrigerant discharged from the compressor 10 is cooled slightly by the secondary throttling device 70, thereby raising the temperature of the refrigerant in the circulation loop S. This reduces the liquid refrigerant content entering the evaporator 40, increases the gaseous refrigerant content flowing out of the evaporator 40, and raises the return gas temperature of the compressor 10.

[0163] At this point, by setting a secondary throttling element 70 and a throttling bypass J to increase the refrigerant dryness at the inlet side of the evaporator 40, the return gas temperature of the compressor 10 can be increased. This method has a lower configuration cost and is more energy-efficient.

[0164] Understandably, the refrigeration system 100 provided in the embodiments of this application can execute the control method in any of the above embodiments, and has the beneficial effects described in the above embodiments, which will not be repeated here.

[0165] Specifically, the refrigeration system 100 also includes a controller, which is connected to the regulating valve 21, main throttling device 30, secondary throttling device 70, first control valve f1, and second control valve f2 in the above embodiments. The controller can execute the control method of the refrigeration system in the above embodiments. The controller can be a central processing unit, microprocessor, embedded microcontroller, computer, mobile smart terminal, or other device or apparatus with data processing and communication functions.

[0166] Furthermore, the testing equipment provided in this application includes a testing terminal and the cooling system 100 described in the above embodiments. The cooling system 100 is used to regulate the temperature of the testing terminal. This testing equipment possesses the beneficial effects described in the above embodiments, which will not be elaborated upon here.

[0167] Typically, the testing equipment also includes a heating device, which works in conjunction with the cooling system 100 to regulate the temperature of the testing terminal. The configuration of the heating device is not specified here; please refer to standard settings.

[0168] Test equipment can be sorting test equipment, probe station equipment, aging test equipment, etc., used for performance testing of semiconductor devices such as chips or wafers. Test terminals can be test heads, test chambers, preheating trays, feed shuttles, wafer carrier trays, etc. A test chamber is a cavity structure that provides test space, and multiple chips or wafers can be stored within it. The evaporator 40 of the cooling system 100 can be arranged within the test space to regulate the test temperature. A test head is a pressure head structure that can press down against the chip, directly contacting it to regulate its temperature. A refrigerant flow path can be provided within the evaporator 40 of the cooling system 100. The refrigerant flowing through the evaporator 40 cools the refrigerant in the refrigerant flow path. The refrigerant flow path can be connected to a pipe inside the test head, and the temperature of the test head is regulated by the refrigerant. A preheating tray is a structure that holds the chip and regulates its temperature. A refrigerant flow path can be connected to a pipe inside the preheating tray, and the temperature of the preheating tray is regulated by the refrigerant. The feed shuttle refers to the structure that transports the chip. A coolant flow path can be connected to the piping within the feed shuttle, allowing the temperature of the feed shuttle to be regulated by the coolant. The wafer carrier tray refers to the structure that holds the wafer by adsorption. A coolant flow path can be connected to the piping within the wafer carrier tray, allowing the temperature of the wafer to be regulated by the coolant.

[0169] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0170] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A control method for a refrigeration system, characterized in that, The refrigeration system includes a compressor (10), a condenser (20), a main throttling device (30) and an evaporator (40) connected in sequence to form a circulation loop (S). The condenser (20) includes a cooling flow path (L1) for the flow of external coolant, and a regulating valve (21) is provided on the cooling flow path (L1). The control method includes: Obtain the current superheat and lower limit of superheat of compressor (10); Based on the current superheat and the lower limit of superheat, it is determined whether the refrigeration system meets the superheat adjustment conditions, which are used to characterize the return gas and liquid of the compressor (10). If the refrigeration system meets the superheat adjustment condition, it enters the control mode, which includes the main throttling device control mode and the regulating valve control mode. In the main throttling device control mode, the opening degree of the main throttling device (30) is reduced; in the regulating valve control mode, the opening degree of the regulating valve (21) is reduced.

2. The control method for the refrigeration system according to claim 1, characterized in that, If the refrigeration system meets the superheat regulation condition, it enters the control mode, including: If the refrigeration system meets the superheat adjustment condition, it enters the main throttling device control mode and determines whether the refrigeration system has reached the first critical condition. The first critical condition is used to characterize that the main throttling device (30) is in a critical state that can be safely controlled. If the refrigeration system does not reach the first critical condition and does not meet the superheat adjustment condition, then exit the main throttling device control mode; If the refrigeration system reaches the first critical condition and satisfies the superheat adjustment condition, it exits the main throttling device control mode and enters the regulating valve control mode.

3. The control method for the refrigeration system according to claim 1 or 2, characterized in that, Lowering the opening of the main throttling element (30) includes: Obtain pressure range information, which is obtained by equally dividing the pressure range formed by the maximum return gas pressure and the minimum return gas pressure of the compressor (10), and obtaining multiple pressure ranges sorted in order of range value size. Obtain the current return gas pressure of the compressor (10), and determine the pressure range in which the current return gas pressure is located as the reference range from the pressure range information based on the current return gas pressure; The target interval is determined based on the control interval and the pressure interval information; the target interval is the pressure interval whose interval value is less than the control interval and whose arrangement order is adjacent to the control interval; A target pressure value is determined based on the target range, wherein the target pressure value belongs to the target range; a first opening reduction is determined based on the target pressure value and a first preset calculation rule; the first preset calculation rule includes taking the target pressure value as the target, performing PID calculation, using the difference between the current return air pressure and the target pressure value as the input variable, and outputting the result as the first opening reduction; The current opening of the main throttling device (30) is reduced according to the first opening reduction.

4. The control method for the refrigeration system according to claim 3, characterized in that, Before determining the target range based on the control range and the pressure range information, the following steps are also included: Determine whether the control interval is the lower limit interval; the lower limit interval is the pressure interval with the smallest interval value. If so, it is determined that the refrigeration system has reached the first critical condition, and the main throttling device control mode is exited. If not, then proceed as follows: Determine the target interval based on the control interval and the pressure interval information.

5. The control method for the refrigeration system according to claim 4, characterized in that, After adjusting the current opening of the main throttling element (30) according to the first opening reduction, the method further includes: The current opening degree of the adjusted main throttling device (30) is used to control the main throttling device (30) to operate for a first duration; If the refrigeration system meets the superheat adjustment condition, then return to the execution: obtain the current return gas pressure of the compressor (10), and determine the pressure range where the current return gas pressure is located as the control range from the pressure range information based on the current return gas pressure.

6. The control method for the refrigeration system according to claim 1 or 2, characterized in that, Lowering the opening of the regulating valve (21) includes: Obtain the target exhaust superheat; Obtain the current exhaust superheat of the compressor (10); The second opening reduction is determined based on the difference between the target exhaust superheat and the current exhaust superheat, and based on a second preset calculation rule. The second preset calculation rule includes calculating the second opening reduction based on the difference between the target exhaust superheat and the current exhaust superheat, and based on PID control logic. The current opening of the regulating valve (21) is reduced by the second opening amount.

7. The control method for the refrigeration system according to claim 6, characterized in that, After reducing the current opening of the regulating valve (21) by the second opening reduction, the method further includes: The second duration of operation of the regulating valve (21) is controlled by the current opening degree of the adjusted regulating valve (21); If the refrigeration system meets the superheat adjustment condition and does not reach the second critical condition, then return to execute: obtain the current exhaust superheat of the compressor (10); The second critical condition is used to characterize that the regulating valve (21) is in a critical state that can be safely controlled, including at least one of the following: the current opening degree of the regulating valve (21) is lower than the lower limit of the opening degree of the regulating valve (21); the current discharge pressure of the compressor (10) is higher than the upper limit of the discharge pressure; and the current discharge superheat of the compressor (10) is higher than the upper limit of the discharge superheat.

8. The control method for the refrigeration system according to claim 2, characterized in that, If the refrigeration system reaches the first critical condition and satisfies the superheat adjustment condition, it exits the main throttling device control mode and enters the regulating valve control mode, further including: If the refrigeration system reaches the second critical condition and meets the superheat regulation condition, it exits the regulating valve control mode and enters the refrigerant temperature control mode until the refrigeration system no longer meets the superheat regulation condition; in the refrigerant temperature control mode, the refrigeration system is controlled to raise the return gas temperature of the compressor (10); The second critical condition is used to characterize that the regulating valve (21) is in a critical state that can be safely controlled, including at least one of the following: the current opening degree of the regulating valve (21) is lower than the lower limit of the opening degree of the regulating valve (21); the current discharge pressure of the compressor (10) is higher than the upper limit of the discharge pressure; and the current discharge superheat of the compressor (10) is higher than the upper limit of the discharge superheat.

9. The control method for the refrigeration system according to claim 8, characterized in that, The circulation loop (S) includes a main return gas path (S1) located between the outlet side of the evaporator (40) and the compressor (10). The refrigeration system includes a return gas bypass (H) connected in parallel with the main return gas path (S1). A regenerator (60) is provided on the return gas bypass (H), and the regenerator (60) has a regenerative flow path (L2) for heating the return gas bypass (H). A first control valve (f1) is provided on the return gas bypass (H) located between the regenerator (60) and the evaporator (40). A second control valve (f2) is provided on the compressor (10); the regenerative flow path (L2) is formed by the flow path located between the compressor (10) and the condenser (20) in the circulation loop (S), or the regenerative flow path (L2) is formed by the cooling flow path (L1), and the coolant in the cooling flow path (L1) flows upward, and the regenerator (60) is located downstream of the condenser (20); the control of the refrigeration system to raise the return gas temperature of the compressor (10) includes: opening the first control valve (f1) and closing the second control valve (f2); And / or, the refrigeration system includes a throttling bypass (J) connected to the inlet side of the condenser (20) and the outlet side of the main throttling device (30), and a secondary throttling device (70) is provided on the throttling bypass (J); the control of the refrigeration system to raise the return gas temperature of the compressor (10) includes: opening the secondary throttling device (70).

10. A refrigeration system, characterized in that, The system includes a compressor (10), a condenser (20), a main throttling device (30), and an evaporator (40) connected in sequence to form a circulation loop (S). The condenser (20) includes a cooling flow path (L1) for the flow of external coolant, and a regulating valve (21) is provided on the cooling flow path (L1). The refrigeration system is capable of performing the control method as described in any one of claims 1 to 9.

11. A testing device, characterized in that, It includes a test terminal and a cooling system as described in claim 10, wherein the cooling system is used to regulate the temperature of the test terminal.

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