Control method of refrigeration system, refrigeration system and test equipment

Abstract

The invention relates to a control method of a refrigerating system, the refrigerating system and testing equipment. The control method comprises the steps that a production instruction of the refrigerating system is obtained, the set liquid outlet temperature associated with the production instruction is determined, and the working mode of the refrigerating system is determined according to the set liquid outlet temperature; when it is determined that the refrigerating system is in the first working mode, a main expansion valve is opened, and the set opening degree associated with the set liquid outlet temperature is determined; the bypass expansion valve is controlled to be opened according to the set opening degree, and the actual liquid outlet temperature of the refrigerating system is obtained; when the relation between the set liquid outlet temperature and the actual liquid outlet temperature shows that the refrigerating system meets the opening degree adjusting condition, the operation opening degree of a bypass expansion valve is adjusted till the actual liquid outlet temperature meets the liquid outlet precision condition; and the current actual liquid outlet temperature of the refrigerating system is obtained, the current actual liquid outlet temperature is updated and recorded as the set liquid outlet temperature related to the production instruction, and the current operation opening degree of the bypass expansion valve is recorded as the set opening degree related to the updated set liquid outlet temperature.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of refrigeration, in particular to a control method of a refrigeration system, the refrigeration system and a test device. BACKGROUND

[0002] Chip testing is an important link in the chip production process, aiming to reduce the early potential failure rate of chips. The chip testing device is usually configured with a refrigeration system to create a test temperature environment. The refrigeration system will adjust the temperature of the refrigerant flowing into the load evaporator (referred to as the outlet liquid temperature) by PID controlling the opening degree of the expansion valve according to the required test temperature (referred to as the production temperature). If the outlet liquid temperature is unstable, the refrigeration capacity of the load evaporator is unstable, resulting in unstable production temperature, which reduces the reliability of the test results. SUMMARY

[0003] Therefore, it is necessary to provide a control method of a refrigeration system, the refrigeration system and a test device to solve the problem that the unstable outlet liquid temperature of the refrigeration system leads to unstable production temperature of the test device and reduces the test results.

[0004] In a first aspect, the present application provides a control method of a refrigeration system, the refrigeration system comprising a first compressor, a first condenser, a main expansion valve and a load evaporator connected in sequence to form a first circulation loop, the refrigeration system further comprising a bypass flow path and a bypass expansion valve arranged in the bypass flow path, the bypass flow path being communicated between the exhaust end of the first compressor and the inlet end of the load evaporator; the control method comprising:

[0005] obtaining a production instruction of the refrigeration system, determining a set outlet liquid temperature associated with the production instruction, and determining a working mode of the refrigeration system according to the set outlet liquid temperature;

[0006] when it is determined that the refrigeration system is in a first working mode, opening the main expansion valve, and determining a set opening degree associated with the set outlet liquid temperature;

[0007] controlling the bypass expansion valve to open at the set opening degree, and obtaining an actual outlet liquid temperature of the refrigeration system;

[0008] when the relationship between the set outlet liquid temperature and the actual outlet liquid temperature indicates that the refrigeration system meets the opening degree adjustment condition, adjusting the running opening degree of the bypass expansion valve until the actual outlet liquid temperature meets the outlet liquid precision condition; the outlet liquid precision condition is that the absolute value of the difference between the actual outlet liquid temperature and the set outlet liquid temperature is less than or equal to the set outlet liquid precision;

[0009] acquiring a current actual outlet temperature of the refrigeration system, updating the current actual outlet temperature as a set outlet temperature associated with the production instruction, and recording a current opening degree of the bypass expansion valve as a set opening degree associated with the updated set outlet temperature.

[0010] In some embodiments, controlling the bypass expansion valve to open at the set opening degree, and acquiring the actual outlet temperature of the refrigeration system, comprises:

[0011] controlling the bypass expansion valve to operate at the set opening degree for a detection period, and acquiring a plurality of actual outlet temperatures within the detection period; wherein the detection period is divided into a first time length and a second time length in sequence, and the plurality of actual outlet temperatures are acquired within the second time length.

[0012] Correspondingly, when the relationship between the set outlet temperature and the actual outlet temperature indicates that the refrigeration system meets the opening degree adjustment condition, adjusting the operating opening degree of the bypass expansion valve until the actual outlet temperature meets the outlet precision condition, comprises:

[0013] When the relationship between the set outlet temperature and the plurality of actual outlet temperatures indicates that the refrigeration system meets the opening degree adjustment condition, adjusting the operating opening degree of the bypass expansion valve, and after each adjustment, controlling the bypass expansion valve to maintain the adjusted operating opening degree for a detection period until the adjustment is stopped when any of the plurality of actual outlet temperatures acquired in the detection period meets the outlet precision condition.

[0014] In some embodiments, when the relationship between the set outlet temperature and the plurality of actual outlet temperatures indicates that the refrigeration system meets the opening degree adjustment condition, adjusting the operating opening degree of the bypass expansion valve, and after each adjustment, controlling the bypass expansion valve to maintain the adjusted operating opening degree for a detection period until the adjustment is stopped when any of the plurality of actual outlet temperatures acquired in the detection period meets the outlet precision condition, comprises:

[0015] determining whether the refrigeration system meets a first opening degree adjustment condition, the first opening degree adjustment condition being that each of the plurality of actual outlet temperatures is less than or equal to the set outlet temperature, the minimum is less than the difference between the set outlet temperature and the outlet precision, and at least one meets the outlet precision condition;

[0016] If so, increasing the operating opening degree of the bypass expansion valve, and after each increase in the operating opening degree of the bypass expansion valve, controlling the bypass expansion valve to maintain the increased operating opening degree for a detection period until the adjustment is stopped when any of the plurality of actual outlet temperatures acquired in the detection period meets the outlet precision condition.

[0017] In some embodiments, when the relationship between the set outlet temperature and the plurality of actual outlet temperatures indicates that the refrigeration system meets the opening degree adjustment condition, the operating opening degree of the bypass expansion valve is adjusted, and after each adjustment, the bypass expansion valve is controlled to maintain the adjusted operating opening degree for a detection period until any of the plurality of actual outlet temperatures obtained in the detection period meets the outlet precision condition, including:

[0018] determining whether the refrigeration system meets a second opening degree adjustment condition, the second opening degree adjustment condition being that each of the plurality of actual outlet temperatures is greater than or equal to the set outlet temperature, and the maximum is greater than the sum of the set outlet temperature and the outlet precision, and at least one meets the outlet precision condition;

[0019] if so, the operating opening degree of the bypass expansion valve is reduced, and after each reduction of the operating opening degree of the bypass expansion valve, the bypass expansion valve is controlled to maintain the reduced operating opening degree for a detection period until any of the plurality of actual outlet temperatures obtained in the detection period meets the outlet precision condition.

[0020] In some embodiments, after the bypass expansion valve is controlled to operate at the set opening degree for a detection period and the plurality of actual outlet temperatures in the detection period are obtained, further comprising:

[0021] when the relationship between the set outlet temperature and the plurality of actual outlet temperatures indicates that the refrigeration system meets an abnormality prompting condition, outputting abnormality prompting information, the abnormality prompting information being used to prompt that the refrigeration system is operating abnormally.

[0022] In some embodiments, the abnormality prompting condition is that the maximum of the plurality of actual outlet temperatures is greater than or equal to the sum of the set outlet temperature and the outlet precision, and the minimum is less than or equal to the difference between the set outlet temperature and the outlet precision.

[0023] In some embodiments, after the working mode of the refrigeration system is determined according to the set outlet temperature, further comprising:

[0024] when it is determined that the refrigeration system is in the second working mode, the main expansion valve is opened and the bypass expansion valve is closed.

[0025] In some embodiments, the production instruction includes a production temperature level, and the set outlet temperature associated with the production instruction is determined, including:

[0026] determining the set outlet temperature associated with the production temperature level.

[0027] In a second aspect, the present application provides a refrigeration system, comprising:

[0028] a first compressor, a first condenser, a main expansion valve and a load evaporator connected in sequence to form a first circulation loop;

[0029] a bypass flow path and a bypass expansion valve provided in the bypass flow path, the bypass flow path being communicated between an exhaust end of the first compressor and an inlet end of the load evaporator; and

[0030] an outlet liquid temperature sensor provided at the inlet end of the load evaporator for detecting an outlet liquid temperature of the refrigeration system; and

[0031] a controller communicatively connected with the outlet liquid temperature sensor, the main expansion valve and the bypass expansion valve, the controller being capable of performing the control method as described in the first aspect.

[0032] In a third aspect, the present application provides a testing device comprising a testing terminal and the refrigeration system as described in the second aspect, the load evaporator being used to adjust a testing temperature of the testing terminal.

[0033] The control method of the refrigeration system, the refrigeration system and the testing device described above, when the refrigeration system acquires a production instruction for the first time, the refrigeration system can update the set outlet liquid temperature matched with the production instruction and update the set opening degree matched with the set outlet liquid temperature. When the same production instruction is acquired next time, the refrigeration system can quickly reach a target outlet liquid temperature without or with less adjustment of the opening degree of the bypass expansion valve, so as to meet the outlet liquid precision condition. In addition, the reduction of the adjustment times of the bypass expansion valve can make the outlet liquid temperature of the refrigeration system more stable and the refrigeration capacity of the load evaporator more stable, so as to make the production temperature of the testing device more stable and ensure the reliability of the testing structure. BRIEF DESCRIPTION OF DRAWINGS

[0034] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The detailed description is made with reference to the accompanying drawings.

[0035] Figure 1 A schematic diagram of the refrigeration system of some embodiments.

[0036] Figure 2 A schematic diagram of the refrigeration system of some other embodiments.

[0037] Figure 3 A flowchart of the control method of the refrigeration system of some embodiments.

[0038] Figure 4Flowchart of the control method of the refrigeration system for some embodiments.

[0039] Figure 5 Refined flowchart of step S41 for some embodiments.

[0040] Figure 6 Refined flowchart of step S41 for some embodiments.

[0041] Figure 7 Flowchart of the control method of the refrigeration system for some embodiments.

[0042] Reference signs in the detailed description are as follows:

[0043] 100, refrigeration system; 10, first refrigeration module; S1, first circulation loop; 11, first compressor; 12, first condenser; 13, main expansion valve; 14, load evaporator; L, bypass flow path; 15, bypass expansion valve; 16, liquid outlet temperature sensor; 17, controller; 20, second refrigeration module; S2, second circulation loop; 21, second compressor; 22, second condenser; 23, throttling device. Detailed description

[0044] In order to make the above objectives, characteristics and advantages of the present application more apparent, obvious and easy to understand, the specific embodiments of the present application are described in detail below in conjunction with the drawings. In the following description, a large number of specific details are set forth in order to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0045] In the description of the present application, it should be understood that if there are any, the orientations or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0046] In addition, the terms "first", "second", and the like, if any, are used merely for descriptive purposes and do not imply or imply a relative importance or an implicit indication of the number of technical features indicated. Thus, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified.

[0047] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0048] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature. The first and second features can be in direct contact, or the first and second features can be indirectly contacted through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be the first feature directly above or obliquely above the second feature, or only indicate that the first feature is higher than the second feature in horizontal height. The first feature "below", "below" and "below" the second feature can be the first feature directly below or obliquely below the second feature, or only indicate that the first feature is lower than the second feature in horizontal height.

[0049] It should be noted that, if any, when an element is referred to as "fixed to" or "provided to" another element, it can be directly on another element or there can be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to another element or there can be a middle element. The terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used herein are for illustrative purposes only and are not the only embodiment.

[0050] In view of the problems pointed out in the background art, the embodiments of the present application propose a control method of a refrigeration system and a refrigeration system, aiming to improve the stability of the liquid temperature of the refrigeration system, to improve the production temperature of the test equipment applied with the refrigeration system, and to improve the reliability of the test results of the test equipment.

[0051] In order to facilitate understanding and description, first introduce the refrigeration system in the embodiments of the present application.

[0052] Figure 1Fig. 1 is a schematic diagram of a refrigeration system 100 according to some embodiments. Please refer to Figure 1 The refrigeration system 100 according to some embodiments includes a first compressor 11, a first condenser 12, a main expansion valve 13 and a load evaporator 14 connected in sequence to form a first circulation loop S1.

[0053] When the refrigeration system 100 is in operation, the refrigerant flows through the first circulation loop S1 as follows: the high-temperature and high-pressure gaseous refrigerant discharged from the discharge end of the first compressor 11 is cooled in the first condenser 12, and then flows through the main expansion valve 13 to become low-temperature and low-pressure liquid refrigerant. The low-temperature and low-pressure liquid refrigerant is cooled in the load evaporator 14 to form low-temperature and low-pressure gaseous refrigerant, which then flows back to the suction end of the first compressor 11 to be compressed again to form high-temperature and high-pressure gaseous refrigerant. The first condenser 12 can be an air-cooled condenser or a water-cooled condenser.

[0054] In addition, the refrigeration system 100 further includes a bypass flow path L, a bypass expansion valve 15 arranged in the bypass flow path L, an outlet liquid temperature sensor 16 and a controller 17. The bypass flow path L is connected between the discharge end of the first compressor 11 and the inlet end of the load evaporator 14. The outlet liquid temperature sensor 16 is arranged at the inlet end of the load evaporator 14 to detect the outlet liquid temperature of the refrigeration system 100. The controller 17 is communicatively connected to the outlet liquid temperature sensor 16, the main expansion valve 13 and the bypass expansion valve 15.

[0055] In actual applications, the load evaporator 14 can be directly or indirectly used to adjust the test temperature of a test device, depending on the type of the test terminal. Details are described below. The inlet end of the bypass flow path L is connected between the first compressor 11 and the first condenser 12, and the outlet end is connected between the main expansion valve 13 and the load evaporator 14. When the bypass expansion valve 15 is opened, the high-temperature and high-pressure gaseous refrigerant discharged from the first compressor 11 is throttled and cooled by the bypass expansion valve 15, and then mixed with the low-temperature and low-pressure liquid refrigerant discharged from the main expansion valve 13 to adjust the temperature of the refrigerant entering the load evaporator 14. In further embodiments, an oil separator is arranged on the first circulation loop S1, the oil separator is located between the first compressor 11 and the first condenser 12, and the inlet end of the bypass flow path L is connected to the first circulation loop S1 between the oil separator and the first condenser 12.

[0056] The outlet liquid temperature sensor 16 is arranged on the first circulation loop S1 between the outlet end of the bypass flow path L and the load evaporator 14 to detect the temperature of the mixed refrigerant (mixed refrigerant) discharged from the bypass expansion valve 15 and the main expansion valve 13, which is referred to as the outlet liquid temperature in the embodiments.

[0057] The controller 17 can adjust the opening of the main expansion valve 13 and the bypass expansion valve 15 according to the detection result of the liquid outlet temperature sensor 16 so that the liquid outlet temperature meets the standard.

[0058] The refrigeration system 100 has a first operating mode and a second operating mode. In the first operating mode, both the main expansion valve 13 and the bypass expansion valve 15 are open, and the bypass flow path L is open. A portion of the high-temperature gaseous refrigerant discharged from the first compressor 11 flows through the main expansion valve 13 via the first circulation loop S1, while the remaining portion flows through the bypass expansion valve 15 via the bypass flow path L. The intermediate-temperature refrigerant discharged from the bypass expansion valve 15 mixes with the low-temperature liquid refrigerant discharged from the main expansion valve 13, resulting in a higher refrigerant temperature flowing through the load evaporator 14 and a lower cooling capacity, suitable for testing scenarios with lower cooling requirements. In the second operating mode, the main expansion valve 13 is open and the bypass expansion valve 15 is closed. All of the refrigerant discharged from the first compressor 11 flows through the first circulation loop S1, resulting in a lower refrigerant temperature flowing through the load evaporator 14 and a higher cooling capacity, suitable for testing scenarios with higher cooling requirements.

[0059] In actual applications, the first operating mode corresponds to the medium-to-high temperature operating conditions of the test equipment, and the second operating mode corresponds to the low-temperature operating conditions of the test equipment. Low-temperature operating conditions and medium-to-high temperature operating conditions are two relative concepts, and the actual production temperature of the test equipment under medium-to-high temperature operating conditions is not limited to being above 0°C.

[0060] Figure 2 FIG. 1 is a schematic diagram of the composition of the refrigeration system 100 in some other embodiments. Figure 2 In other embodiments, the refrigeration system 100 includes a first refrigeration module 10 and a second refrigeration module 20, wherein the first refrigeration module 10 includes the above-mentioned first compressor 11, first condenser 12, main expansion valve 13, bypass expansion valve 15, load evaporator 14, etc. The second refrigeration module 20 includes a second compressor 21, a second condenser 22, and a throttling device 23. The second compressor 21, the second condenser 22, the throttling device 23, and the first condenser 12 are sequentially connected to form a second circulation loop S2. The first condenser 12 is thermally coupled to the first circulation loop S1 and the second circulation loop S2. The refrigerant in the second circulation loop S2 is cooled by the first condenser 12 to reduce the temperature of the refrigerant in the first circulation loop S1, so that the load evaporator 14 has a higher refrigeration capacity and provides a lower production temperature for the test equipment.

[0061] Understandably, when the refrigeration system 100 only includes the first refrigeration module 10, it is a single-stage system. When the refrigeration system 100 includes the first refrigeration module 10 and the second refrigeration module 20, it is a cascade system. If the refrigeration system 100 is a cascade system, the second compressor 21 and the throttling device 23 are turned on in the second working mode. In the first working mode, the second compressor 21 and the throttling device 23 can be turned on or not.

[0062] It is worth mentioning that, in the refrigeration system 100 of the embodiments of the present application, the bypass flow path L and the bypass expansion valve 15 are arranged, so that the refrigeration system 100 can adapt to different working condition requirements of the test system and provide different refrigeration capacities.

[0063] The control method of the refrigeration system 100 in the embodiments of the present application will be described in detail below based on the refrigeration system 100 in the above embodiments.

[0064] Figure 3 The flowchart of the control method of the refrigeration system 100 of some embodiments is shown in FIG. 1. Please refer to Figure 3 The control method of the refrigeration system 100 proposed in the embodiments of the present application includes:

[0065] S1, obtaining a production instruction of the refrigeration system 100, determining a set outlet temperature associated with the production instruction, and determining a working mode of the refrigeration system 100 according to the set outlet temperature.

[0066] The production instruction is used to represent the production requirement (test requirement) of the test equipment. The controller 17 of the refrigeration system 100 can obtain the production instruction from the control center of the test equipment, or directly obtain the production instruction input by the user through the human-computer interaction interface. The production instruction can include working condition modes (such as low-temperature working condition, medium-temperature working condition, and high-temperature working condition), production temperature, production temperature level, and other parameters that can represent the test requirement.

[0067] The first association relationship between the production instruction and the set outlet temperature is pre-stored in the controller 17, and the set outlet temperature associated with the obtained production instruction is determined according to the association relationship. Different production instructions are pre-associated with different set outlet temperatures.

[0068] The set outlet temperature is the target temperature of the refrigerant flowing into the load evaporator 14 matched with the production instruction. Different set outlet temperatures correspond to different working modes of the refrigeration system 100. For example, when the set outlet temperature is lower than -15℃, the load evaporator 14 needs to provide a larger refrigeration capacity, and the working mode of the refrigeration system 100 is the second working mode. When the set outlet temperature is lower than 0℃ and higher than -15℃, the load evaporator 14 needs to provide a lower refrigeration capacity, and the working mode of the refrigeration system 100 is the first working mode.

[0069] S2, when determining that the refrigeration system 100 is in the first working mode, opening the main expansion valve 13, and determining the set opening degree associated with the set outlet temperature.

[0070] The determination of the working mode of the refrigeration system 100 is used to determine whether to open the bypass expansion valve 15. As described above, when it is determined that the working mode of the refrigeration system 100 is the first working mode, the bypass expansion valve 15 is opened. When it is determined that the working mode of the refrigeration system 100 is the second working mode, the bypass expansion valve 15 is closed.

[0071] It can be understood that no matter whether the refrigeration system 100 is in the first working mode or the second working mode, the main expansion valve 13 is opened, and the refrigerant circulates in the first circulation loop S1, so that the load evaporator 14 can cool externally.

[0072] The controller 17 has a second correlation relationship between the set outlet temperature and the set opening degree of the bypass expansion valve 15 stored in advance. When it is determined that the refrigeration system 100 is in the first working mode, it is necessary to open the bypass expansion valve 15, and the set opening degree associated with the set outlet temperature is determined according to the second correlation relationship. The set opening degree represents the initial opening degree of the bypass expansion valve 15 in the first working mode.

[0073] It should be noted that in the first working mode, the working opening degree of the main expansion valve 13 is a preset fixed value. In some embodiments, the controller 17 can store a third correlation relationship between the set outlet temperature and the working opening degree of the main expansion valve 13. The working opening degree of the main expansion valve 13 matched with the set outlet temperature is determined according to the third correlation relationship, and the main expansion valve 13 is opened at the working opening degree. In other embodiments, in the first working mode, the main expansion valve 13 maintains a fixed working opening degree (such as 50%), and no matter the size of the set outlet temperature, the main expansion valve 13 is controlled to open at the working opening degree. It can be understood that in the second working mode, the refrigeration demand of the load evaporator 14 is larger, and the working opening degree of the main expansion valve 13 is usually larger than that in the first working mode.

[0074] S3, opening the bypass expansion valve 15 at the set opening degree to obtain the actual outlet temperature of the refrigeration system 100.

[0075] The set opening degree is the initial opening degree of the bypass expansion valve 15. After the main expansion valve 13 is opened, the bypass expansion valve 15 is opened at the set opening degree, so that a part of the high-temperature gaseous refrigerant discharged by the first compressor 11 flows through the bypass expansion valve 15 through the bypass flow path L, and the other part of the refrigerant passes through the first condenser 12 and the main expansion valve 13 in sequence, and then mixes with the refrigerant flowing out of the bypass expansion valve 15, so as to adjust the temperature of the refrigerant entering the load evaporator 14, so that the temperature is not too low, and then the refrigeration capacity of the load evaporator 14 matches the production demand.

[0076] After the bypass expansion valve 15 is opened at a set opening for a certain period of time to stabilize the system operation, the actual outlet liquid temperature of the refrigeration system 100 is obtained. Specifically, the controller 17 obtains the actual outlet liquid temperature from the outlet liquid temperature sensor 16.

[0077] S4. When the relationship between the set liquid outlet temperature and the actual liquid outlet temperature indicates that the refrigeration system 100 meets the opening adjustment condition, adjust the operating opening of the bypass expansion valve 15 until the actual liquid outlet temperature meets the liquid outlet accuracy condition; wherein, the liquid outlet accuracy condition is that the absolute value of the difference between the actual liquid outlet temperature and the set liquid outlet temperature is less than or equal to the set liquid outlet accuracy.

[0078] The actual liquid outlet temperature is denoted as Ts, the set liquid outlet temperature is denoted as Ti, and the liquid outlet accuracy is denoted as β. The liquid outlet accuracy condition is |Ts-Ti|≦β, that is, the difference between the actual liquid outlet temperature and the set liquid outlet temperature is within the allowable fluctuation range. The smaller β, the smaller the fluctuation range and the higher the liquid outlet temperature accuracy. β can optionally be within the range of 0.1°C to 5°C, and specifically can be 1°C, 2°C, or 3°C, etc.

[0079] When the refrigeration system 100 meets the opening adjustment condition, it indicates that the actual liquid outlet temperature of the refrigeration system 100 does not meet the liquid outlet accuracy condition. The opening of the bypass expansion valve 15 needs to be adjusted to ensure that the actual liquid outlet temperature meets the liquid outlet accuracy condition. The opening adjustment condition can be set so that the actual liquid outlet temperature does not meet the liquid outlet accuracy condition.

[0080] When adjusting the opening of the bypass expansion valve 15, if Ts is greater than Ti, reduce the opening of the bypass expansion valve 15; if Ts is less than Ti, increase the opening of the bypass expansion valve 15. Repeat this adjustment until the actual liquid outlet temperature meets the liquid outlet accuracy requirements.

[0081] When adjusting the operating opening of the bypass expansion valve 15, based on PID control, the operating opening of the bypass expansion valve 15 can be increased or decreased by a preset percentage based on the current operating opening. Alternatively, the operating opening of the bypass expansion valve 15 can be gradually increased or decreased based on the set opening.

[0082] After each adjustment of the opening of the bypass expansion valve 15 and after it stabilizes for a first period of time, the actual outlet liquid temperature of the refrigeration system 100 is re-obtained. If the actual outlet liquid temperature does not meet the outlet liquid accuracy requirements, the next opening adjustment is performed. If the re-obtained actual outlet liquid temperature meets the outlet liquid accuracy requirements after the opening adjustment, the opening adjustment is stopped.

[0083] S5, obtaining the current actual outlet temperature of the refrigeration system 100, updating the current actual outlet temperature as the set outlet temperature associated with the production instruction, and recording the current operating opening of the bypass expansion valve 15 as the set opening associated with the updated set outlet temperature.

[0084] When the outlet precision condition is met after the opening adjustment, it indicates that the fluctuation of the actual outlet temperature compared with the set outlet temperature is within the allowable range. At this time, the controller 17 obtains the current actual outlet temperature of the refrigeration system 100 from the outlet temperature sensor 16, and updates the actual outlet temperature as the set outlet temperature associated with the production instruction obtained in the above step S1 in the pre-stored first correlation relationship, that is, replaces the set outlet temperature associated with the production instruction obtained in the step S1. At the same time, when the outlet precision condition is met after the opening adjustment, the controller 17 obtains the current operating opening of the bypass expansion valve 15, and records the operating opening as the set opening associated with the updated set outlet temperature (i.e. the current actual outlet temperature is reacquired) in the second correlation relationship.

[0085] In this way, the refrigeration system 100 can update the set outlet temperature associated with the production instruction and update the set opening associated with the set outlet temperature when the production instruction is obtained for the first time. When the refrigeration system 100 acquires the same production instruction next time, the refrigeration system 100 can quickly reach the target outlet temperature without adjusting or with less adjustment of the opening of the bypass expansion valve 15, so as to meet the outlet precision condition. In addition, the reduction of the adjustment times of the bypass expansion valve 15 can make the outlet temperature of the refrigeration system 100 more stable, the refrigeration capacity of the load evaporator 14 more stable, and the production temperature of the test equipment more stable, thereby ensuring the reliability of the test structure.

[0086] Figure 4 Flowchart of the control method of the refrigeration system 100 of some other embodiments.

[0087] In some embodiments, the control method of the refrigeration system 100 is combined with the production instruction of the test equipment. Figure 4 It is understood that the step S3 of controlling the bypass expansion valve 15 to open at the set opening and obtaining the actual outlet temperature of the refrigeration system 100 specifically includes:

[0088] S31, controlling the bypass expansion valve 15 to operate at the set opening for a detection period, and obtaining a plurality of actual outlet temperatures in the detection period; wherein the detection period is divided into a first time length and a second time length in sequence, and the plurality of actual outlet temperatures are obtained in the second time length.

[0089] Correspondingly, when the relationship between the set outlet temperature and the actual outlet temperatures indicates that the refrigeration system 100 meets the opening degree adjustment condition, the operating opening degree of the bypass expansion valve 15 is adjusted until the actual outlet temperature meets the outlet precision condition in step S4, which specifically includes:

[0090] S41, when the relationship between the set outlet temperature and the actual outlet temperatures indicates that the refrigeration system 100 meets the opening degree adjustment condition, the operating opening degree of the bypass expansion valve 15 is adjusted, and after each adjustment, the bypass expansion valve 15 is controlled to keep the adjusted operating opening degree for a detection period, until any of the plurality of actual outlet temperatures obtained in the detection period meets the outlet precision condition.

[0091] The bypass expansion valve 15 is controlled at the set opening degree for a detection period. The detection period is divided into two time periods in sequence, the first time period and the second time period. In the first time period, the bypass expansion valve 15 is kept open at the current operating opening degree to stabilize the operation of the refrigeration system 100, and then a plurality of actual outlet temperatures are obtained in the second time period.

[0092] The detection period in which the bypass expansion valve 15 is kept open at the set opening degree as the operating opening degree is defined as the first detection period. Whether the plurality of actual outlet temperatures obtained in the first detection period meets the opening degree adjustment condition is determined. If the opening degree adjustment condition is met, the operating opening degree of the bypass expansion valve 15 is adjusted.

[0093] After each adjustment, the bypass expansion valve 15 is controlled to keep the adjusted operating opening degree for a detection period. If any of the plurality of actual outlet temperatures obtained in the detection period meets the outlet precision condition, the adjustment is stopped. If at least one of the plurality of actual outlet temperatures obtained in the detection period does not meet the outlet precision condition, the operating opening degree of the bypass expansion valve 15 is continuously adjusted until the bypass expansion valve 15 keeps the adjusted operating opening degree for a detection period, and the plurality of actual outlet temperatures obtained in the detection period meet the outlet precision condition, and then the adjustment is stopped.

[0094] In this way, the actual outlet temperature is obtained only after the bypass expansion valve 15 adjusts the opening degree and stabilizes for a first time period, which can more truly reflect the outlet temperature of the refrigerant and is more accurate. Moreover, the opening degree adjustment is exited only when all of the plurality of obtained actual outlet temperatures meet the outlet precision condition, i.e., the opening degree adjustment is exited only when it is determined that the outlet temperature is stable and meets the outlet precision condition, which ensures the stable operation of the refrigeration system 100 and further ensures the stability of the adjusted outlet temperature.

[0095] The first time length is greater than the second time length. The first time length can be 1 min to 10 min (such as 2 min, 3 min, 5 min), and the second time length can be 10 s to 90 s (such as 30 s, 60 s). The actual liquid outlet temperature can be obtained every n seconds within the second time length, and n can be 2, 3, 4, 5, etc. The more actual liquid outlet temperatures obtained within the second time length, the more truly the liquid outlet stability can be reflected.

[0096] In actual application, when any one of the plurality of actual liquid outlet temperatures obtained in the first detection period meets the liquid outlet precision condition, the control program is ended, and the set liquid outlet temperature associated with the production instruction does not need to be updated.

[0097] Figure 5 A detailed flowchart of step S41 of some embodiments.

[0098] In some embodiments, with reference to Figure 5 When the relationship between the set liquid outlet temperature and the plurality of actual liquid outlet temperatures indicates that the refrigeration system 100 meets the opening degree adjustment condition, the step S41 of adjusting the operating opening degree of the bypass expansion valve 15 and, after each adjustment, controlling the bypass expansion valve 15 to maintain the adjusted operating opening degree for a detection period until any one of the plurality of actual liquid outlet temperatures obtained in the detection period meets the liquid outlet precision condition, specifically includes:

[0099] S41a, determining whether the refrigeration system 100 meets a first opening degree adjustment condition. The first opening degree adjustment condition is that each of the plurality of actual liquid outlet temperatures is less than or equal to the set liquid outlet temperature, the minimum is less than the difference between the set liquid outlet temperature and the liquid outlet precision, and at least one meets the liquid outlet precision condition.

[0100] When the plurality of actual liquid outlet temperatures simultaneously meet Ts≤Ti, Ts min When the plurality of actual liquid outlet temperatures simultaneously meet Ts≤Ti, Ts

[0101] S41b, if the first opening degree adjustment condition is met, the operating opening degree of the bypass expansion valve 15 is increased, and after each increase of the operating opening degree of the bypass expansion valve 15, the bypass expansion valve 15 is controlled to maintain the increased operating opening degree for a detection period until any one of the plurality of actual liquid outlet temperatures obtained in the detection period meets the liquid outlet precision condition.

[0102] When the refrigeration system 100 meets the first opening degree adjustment condition, the opening degree of the bypass expansion valve 15 is increased based on the set opening degree, and the bypass expansion valve 15 is controlled to keep the increased opening degree for a detection period, and a plurality of actual outlet temperatures in the detection period are obtained. If the plurality of actual outlet temperatures do not meet the outlet temperature precision condition, the opening degree of the bypass expansion valve 15 is continuously increased until the opening degree of the bypass expansion valve 15 is adjusted to the opening degree that meets the outlet temperature precision condition.

[0103] For example, when the refrigeration system 100 meets the first opening degree adjustment condition, the opening degree of the bypass expansion valve 15 is increased based on the set opening degree to obtain a first opening degree, the bypass expansion valve 15 is controlled to keep the first opening degree for a detection period, and a plurality of actual outlet temperatures in the detection period are obtained. If the plurality of actual outlet temperatures do not meet the outlet temperature precision condition, the opening degree of the bypass expansion valve 15 is continuously increased to obtain a second opening degree, the bypass expansion valve 15 is controlled to keep the second opening degree for a detection period, and a plurality of actual outlet temperatures in the detection period are obtained. If the plurality of actual outlet temperatures do not meet the outlet temperature precision condition, the opening degree of the bypass expansion valve 15 is continuously increased to obtain a third opening degree, and so on, until the plurality of actual outlet temperatures obtained in the last detection period meet the outlet temperature precision condition, the opening degree of the bypass expansion valve 15 is stopped from being increased, and step S5 is performed.

[0104] Figure 6 The detailed flowchart of step S41 of some other embodiments.

[0105] In some embodiments, when the relationship between the set outlet temperature and the plurality of actual outlet temperatures indicates that the refrigeration system 100 meets the opening degree adjustment condition, the step S41 of adjusting the opening degree of the bypass expansion valve 15 and, after each adjustment, controlling the bypass expansion valve 15 to keep the adjusted opening degree for a detection period until any one of the plurality of actual outlet temperatures obtained in the detection period meets the outlet temperature precision condition, specifically includes:

[0106] S41c, judging whether the refrigeration system 100 meets a second opening degree adjustment condition, the second opening degree adjustment condition being that each of the plurality of actual outlet temperatures is greater than or equal to the set outlet temperature, the maximum is greater than the sum of the set outlet temperature and the outlet temperature precision, and at least one meets the outlet temperature precision condition.

[0107] When the plurality of actual outlet temperatures simultaneously meet Ts≥Ti, Ts maxWhen the Ti+β and at least one Ts satisfy the liquid outlet precision condition, it is determined that the refrigeration system 100 satisfies the second opening degree adjustment condition. When the refrigeration system 100 satisfies the second opening degree adjustment condition, it indicates that each actual liquid outlet temperature is higher than the set liquid outlet temperature, and the liquid outlet temperature at some time satisfies the liquid outlet precision requirement, and the liquid outlet temperature at some time does not satisfy the liquid outlet precision requirement.

[0108] In S41d, if the condition is satisfied, the operation opening degree of the bypass expansion valve 15 is reduced, and after each reduction of the operation opening degree of the bypass expansion valve 15, the bypass expansion valve 15 is controlled to maintain the reduced operation opening degree for a detection period, and the adjustment is stopped until any one of the plurality of actual liquid outlet temperatures obtained in the detection period satisfies the liquid outlet precision condition.

[0109] When the refrigeration system 100 satisfies the second opening degree adjustment condition, the operation opening degree of the bypass expansion valve 15 is reduced on the basis of the set opening degree, and the bypass expansion valve 15 is controlled to maintain the reduced operation opening degree for a detection period, and the plurality of actual liquid outlet temperatures in the detection period are obtained, and if the plurality of actual liquid outlet temperatures do not satisfy the liquid outlet precision condition, the operation opening degree of the bypass expansion valve 15 is continuously increased, and the adjustment is stopped until all the actual liquid outlet temperatures obtained in the last detection period satisfy the liquid outlet precision condition.

[0110] For example, when the refrigeration system 100 satisfies the second opening degree adjustment condition, the operation opening degree of the bypass expansion valve 15 is reduced on the basis of the set opening degree to obtain a first operation opening degree, the bypass expansion valve 15 is controlled to maintain the first operation opening degree for a detection period, and the plurality of actual liquid outlet temperatures in the detection period are obtained, and if the plurality of actual liquid outlet temperatures do not satisfy the liquid outlet precision condition, the operation opening degree of the bypass expansion valve 15 is continuously reduced to obtain a second operation opening degree, the bypass expansion valve 15 is controlled to maintain the second operation opening degree for a detection period, and the plurality of actual liquid outlet temperatures in the detection period are obtained, and if the plurality of actual liquid outlet temperatures do not satisfy the liquid outlet precision condition, the operation opening degree of the bypass expansion valve 15 is continuously reduced to obtain a third operation opening degree, and the cycle is repeated, and when the plurality of actual liquid outlet temperatures obtained in the last detection period satisfy the liquid outlet precision condition, the reduction of the operation opening degree of the bypass expansion valve 15 is stopped, and S5 is executed.

[0111] When the operation opening degree of the bypass expansion valve 15 is increased, the opening degree of a set proportion can be increased on the basis of the current operation opening degree. When the operation opening degree of the bypass expansion valve 15 is reduced, the opening degree of a set proportion can be reduced on the basis of the current operation opening degree.

[0112] Figure 7 The flowchart of the control method of the refrigeration system 100 of some other embodiments.

[0113] In some embodiments, with reference to Figure 7, the method further comprises:

[0114] S6, when the relationship between the set outlet temperature and the plurality of actual outlet temperatures indicates that the refrigeration system 100 meets the abnormal reminding condition, outputting an abnormal reminding information, the abnormal reminding information being used to remind that the refrigeration system 100 is abnormal.

[0115] When the refrigeration system 100 meets the abnormal reminding condition, it indicates that the system has abnormal conditions, such as insufficient refrigerant, compressor abnormality, etc., which leads to the failure to achieve the required outlet temperature. Therefore, the controller 17 outputs the abnormal reminding information to the warning device, such as a buzzer, a siren, a computer, a mobile terminal, to inform the staff that the system is abnormal and needs to be repaired, so as to avoid testing the equipment when the refrigeration system 100 is abnormal, and to ensure the accuracy and reliability of the test results.

[0116] In specific embodiments, the abnormal reminding condition is that the maximum of the plurality of actual outlet temperatures is greater than or equal to the sum of the set outlet temperature and the outlet precision, and the minimum is less than or equal to the difference between the set outlet temperature and the outlet precision.

[0117] That is, when Ts max ≥ Ti + β and Ts min ≤ Ti - β, the refrigeration system 100 meets the abnormal reminding condition. According to the formula, when the refrigeration system 100 meets the abnormal reminding condition, the actual outlet temperature fluctuates greatly in the corresponding detection period, and the refrigerant outlet temperature is very unstable. The opening degree of the bypass expansion valve 15 cannot be adjusted by PID to stabilize the refrigerant temperature within the allowable range of the outlet precision, and the system oscillates severely, which needs manual intervention to troubleshoot the cause.

[0118] In some embodiments, with reference to Figure 7 , after determining the working mode of the refrigeration system 100 according to the set outlet temperature, the method further comprises:

[0119] S7, when it is determined that the refrigeration system 100 is in the second working mode, opening the main expansion valve 13 and closing the bypass expansion valve 15.

[0120] As described above, when the set outlet temperature associated with the production instruction is low, the test equipment needs the refrigeration system 100 to provide a larger refrigeration capacity, and the system enters the second working mode. In the second working mode, the bypass expansion valve 15 is closed, and the main expansion valve 13 is opened, so that the refrigerant discharged by the first compressor 11 all participates in the circulation on the first circulation loop S1, and the refrigeration capacity of the refrigerant is fully utilized.

[0121] Understandably, when the refrigeration system 100 is a cascade system, the second compressor 21 and the throttling device 23 can be opened synchronously when the step S7 is performed, the refrigerant on the second circulation loop S2 is used to cool the refrigerant on the first circulation loop S1, the refrigeration capacity of the refrigerant on the first circulation loop S1 is improved, and the refrigeration capacity of the load evaporator 14 is further improved.

[0122] In actual application, the initial opening degree of the main expansion valve 13 in the second working mode can be determined according to the set outlet liquid temperature. After the main expansion valve 13 operates at the initial opening degree for a detection period, a plurality of actual outlet liquid temperatures in the detection period are obtained, and it is determined whether the plurality of actual outlet liquid temperatures meet the outlet liquid precision condition. If not, it is determined whether the opening degree adjustment condition is met or the abnormality reminding condition is met according to the method in the above embodiment.

[0123] If the first opening degree adjustment condition is met, the operating opening degree of the main expansion valve 13 is gradually increased on the basis of the initial opening degree of the main expansion valve 13, and the opening degree of the main expansion valve 13 is stopped increasing when the plurality of actual outlet liquid temperatures obtained in a detection period that the main expansion valve 13 maintains at the increased operating opening degree meet the outlet liquid precision condition.

[0124] If the second opening degree adjustment condition is met, the operating opening degree of the main expansion valve 13 is gradually decreased on the basis of the initial opening degree of the main expansion valve 13, and the opening degree of the main expansion valve 13 is stopped decreasing when the plurality of actual outlet liquid temperatures obtained in a detection period that the main expansion valve 13 maintains at the decreased operating opening degree meet the outlet liquid precision condition.

[0125] If the abnormality reminding condition is met, abnormality reminding information is output to inform the worker to overhaul the system.

[0126] In some embodiments, the production instruction includes a production temperature level, and accordingly, the set outlet liquid temperature associated with the production instruction is determined, including:

[0127] S11, determining the set outlet liquid temperature associated with the production temperature level.

[0128] In actual application, a plurality of production temperature levels, such as 1 level, 2 level, 3 level, 4 level, and the like, can be pre-set according to different test temperatures. It can be set that the higher the level, the higher the required test temperature. A first association relationship between different levels and set outlet liquid temperatures is pre-stored, and the controller 17 can determine the set outlet liquid temperature matched with the production temperature level according to the first association relationship after obtaining the production temperature level.

[0129] At this time, the production instruction contains a production temperature level, which can match the situation of determining the test temperature in the test equipment by level. The test personnel only need to select the production temperature level, without the need for the test personnel to remember the specific temperature size, which is more convenient for the test personnel to use.

[0130] In a specific embodiment of the present application, the control process of the refrigeration system 100 is as follows:

[0131] P1, obtaining the production instruction of the refrigeration system 100, determining the set outlet temperature associated with the production instruction, and determining the working mode of the refrigeration system 100 according to the set outlet temperature;

[0132] P2, if it is determined that the refrigeration system 100 is in the first working mode, opening the main expansion valve 13 at a fixed opening degree, and determining the set opening degree associated with the set outlet temperature;

[0133] P3, controlling the bypass expansion valve 15 to operate at the set opening degree for a detection period, and obtaining a plurality of actual outlet temperatures within the detection period;

[0134] P5, determining whether each of the plurality of actual outlet temperatures satisfies the outlet precision condition: Ti-β≤Ts≤Ti+β; if yes, ending the control and not updating the set outlet temperature associated with the production instruction;

[0135] P6, if no, determining whether the plurality of actual outlet temperatures satisfies the abnormal reminding condition: Ts max ≥Ti+β and Ts min ≤Ti-β; if yes, outputting an abnormal reminding information and ending the control;

[0136] P7, if no, determining whether the plurality of actual outlet temperatures satisfies the first opening degree adjustment condition: Ts≤Ti, Ts min <Ti-β and at least one Ts satisfies the outlet precision condition; if yes, increasing the operating opening degree of the bypass expansion valve 15, and after each increase of the operating opening degree of the bypass expansion valve 15, controlling the bypass expansion valve 15 to maintain the increased operating opening degree for a detection period, and obtaining a plurality of actual outlet temperatures within the detection period, and continuing to determine whether the plurality of actual outlet temperatures satisfies the outlet precision condition, if not, continuing to increase the operating opening degree of the bypass expansion valve 15, until the bypass expansion valve 15 maintains the increased operating opening degree for a detection period, and the plurality of actual outlet temperatures obtained within the detection period satisfies the outlet precision condition, then stopping the increase of the opening degree, and executing step P9;

[0137] P8, if no, determining whether the plurality of actual outlet temperatures satisfies the second opening degree adjustment condition: Ts≥Ti, Ts maxTi+β, and at least one Ts satisfies the liquid outlet precision condition; if yes, the operation opening degree of the bypass expansion valve 15 is reduced, and after each reduction of the operation opening degree of the bypass expansion valve 15, the bypass expansion valve 15 is controlled to keep the reduced operation opening degree for a detection period, and a plurality of actual liquid outlet temperatures in the detection period are obtained, and it is continuously judged whether the plurality of actual liquid outlet temperatures satisfy the liquid outlet precision condition, if not, the operation opening degree of the bypass expansion valve 15 is continuously reduced, until the bypass expansion valve 15 keeps the reduced operation opening degree for a detection period, and the plurality of actual liquid outlet temperatures obtained in the detection period satisfy the liquid outlet precision condition, the reduction of the opening degree is stopped, and step P9 is executed;

[0138] P9, the current actual liquid outlet temperature is re-obtained, and the current actual liquid outlet temperature is recorded as the set liquid outlet temperature associated with the production instruction, and the current operation opening degree of the bypass expansion valve 15 is obtained, and the current operation opening degree is recorded as the set opening degree associated with the set liquid outlet temperature.

[0139] The controller 17 in the refrigeration system 100 proposed in the embodiments of the present application can execute the control method of any one of the above embodiments.

[0140] In addition, the embodiments of the present application also propose a test device, which comprises a test terminal and the refrigeration system 100 in the above embodiments, and the load evaporator 14 is used to adjust the temperature of the test terminal. The test device has the beneficial effects of the above embodiments, and will not be repeated here.

[0141] Desirably, the test device further comprises a heating device, and the heating device and the refrigeration system 100 cold and heat against each other to jointly adjust the temperature of the test terminal. The setting mode of the heating device is referred to the conventional setting, and is not limited here.

[0142] The test equipment can be a sorting test equipment, a probe station equipment, an aging test equipment, etc., for performance testing of semiconductor devices such as chips or wafers. The test terminal can be a test head, a test cavity, a pre-warming disc, a shuttle, a wafer carrier plate, etc. The test cavity is a cavity structure for providing a test space, and a plurality of chips or wafers can be stored in the test space. The load evaporator 14 can be arranged in the test space to adjust the test temperature of the test space. The test head refers to a head structure capable of pressing against the chip, which directly contacts the chip to regulate the temperature of the chip. A load refrigerant flow path can be provided in the load evaporator 14, and the load evaporator 14 cools the load refrigerant in the load refrigerant flow path by flowing through the refrigerant. The load refrigerant flow path can be connected to the pipeline in the test head, and the temperature of the test head can be adjusted by the load refrigerant. The pre-warming disc refers to a structure for carrying chips and adjusting the temperature of the chips. The load refrigerant flow path can be connected to the pipeline in the pre-warming disc, and the temperature of the pre-warming disc can be adjusted by the load refrigerant. The shuttle refers to a structure for transporting chips. The load refrigerant flow path can be connected to the pipeline in the shuttle, and the temperature of the shuttle can be adjusted by the load refrigerant. The wafer carrier plate refers to a structure for carrying wafers by adsorption. The load refrigerant flow path can be connected to the pipeline in the wafer carrier plate, and the test temperature of the wafer can be adjusted by the load refrigerant.

[0143] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, but as long as the combinations of the technical features do not contradict, they should be considered within the scope of the present disclosure.

[0144] The above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present application. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the scope of protection of the patent of the present application should be subject to the appended claims.

Claims

1. A control method for a refrigeration system, characterized in that: The refrigeration system includes a first compressor, a first condenser, a main expansion valve, and a load evaporator connected in sequence to form a first circulation loop, the refrigeration system also includes a bypass flow path and a bypass expansion valve provided on the bypass flow path, the bypass flow path is connected between the exhaust end of the first compressor and the inlet end of the load evaporator; the control method includes: Obtaining a production instruction of the refrigeration system, determining a set liquid outlet temperature associated with the production instruction, and determining an operating mode of the refrigeration system according to the set liquid outlet temperature; When it is determined that the refrigeration system is in the first operating mode, opening the main expansion valve and determining a set opening associated with the set liquid outlet temperature; Controlling the bypass expansion valve to open with the set opening to obtain the actual liquid outlet temperature of the refrigeration system; When the relationship between the set liquid outlet temperature and the actual liquid outlet temperature indicates that the refrigeration system meets the opening adjustment condition, the operating opening of the bypass expansion valve is adjusted until the actual liquid outlet temperature meets the liquid outlet accuracy condition; the liquid outlet accuracy condition is that the absolute value of the difference between the actual liquid outlet temperature and the set liquid outlet temperature is less than or equal to the set liquid outlet accuracy; Obtain the current actual liquid outlet temperature of the refrigeration system, update and record the current actual liquid outlet temperature as the set liquid outlet temperature associated with the production instruction, and record the current operating opening of the bypass expansion valve as the set opening associated with the updated set liquid outlet temperature.

2. The control method of the refrigeration system according to claim 1, characterized in that: Controlling the bypass expansion valve to open with the set opening to obtain the actual liquid outlet temperature of the refrigeration system includes: controlling the bypass expansion valve to operate at the set opening for a detection cycle, and obtaining a plurality of actual liquid outlet temperatures within the detection cycle; wherein the detection cycle is successively divided into a first time period and a second time period, and the plurality of actual liquid outlet temperatures are obtained within the second time period; Accordingly, when the relationship between the set liquid outlet temperature and the actual liquid outlet temperature indicates that the refrigeration system meets the opening adjustment condition, adjusting the operating opening of the bypass expansion valve until the actual liquid outlet temperature meets the liquid outlet accuracy condition includes: When the relationship between the set liquid outlet temperature and the multiple actual liquid outlet temperatures indicates that the refrigeration system meets the opening adjustment condition, the operating opening of the bypass expansion valve is adjusted, and after each adjustment, the bypass expansion valve is controlled to maintain the adjusted operating opening for one detection cycle until any one of the multiple actual liquid outlet temperatures obtained in the detection cycle meets the liquid outlet accuracy condition, and the adjustment is stopped.

3. The control method of the refrigeration system according to claim 2, characterized in that: When the relationship between the set liquid outlet temperature and the multiple actual liquid outlet temperatures indicates that the refrigeration system meets the opening adjustment condition, the operating opening of the bypass expansion valve is adjusted, and after each adjustment, the bypass expansion valve is controlled to maintain the adjusted operating opening for one detection cycle until any one of the multiple actual liquid outlet temperatures obtained in the detection cycle meets the liquid outlet accuracy condition, and the adjustment is stopped, including: determining whether the refrigeration system satisfies a first opening adjustment condition, the first opening adjustment condition being that each of the plurality of actual liquid outlet temperatures is less than or equal to the set liquid outlet temperature, the smallest of the plurality of actual liquid outlet temperatures is less than a difference between the set liquid outlet temperature and the liquid outlet accuracy, and at least one of the plurality of actual liquid outlet temperatures satisfies the liquid outlet accuracy condition; If the conditions are met, the operating opening of the bypass expansion valve is increased, and after each increase in the operating opening of the bypass expansion valve, the bypass expansion valve is controlled to maintain the increased operating opening for one detection cycle until any one of the multiple actual liquid outlet temperatures obtained in the detection cycle meets the liquid outlet accuracy condition and the adjustment is stopped.

4. The control method of the refrigeration system according to claim 2, characterized in that: When the relationship between the set liquid outlet temperature and the multiple actual liquid outlet temperatures indicates that the refrigeration system meets the opening adjustment condition, the operating opening of the bypass expansion valve is adjusted, and after each adjustment, the bypass expansion valve is controlled to maintain the adjusted operating opening for one detection cycle until any one of the multiple actual liquid outlet temperatures obtained in the detection cycle meets the liquid outlet accuracy condition, and the adjustment is stopped, including: determining whether the refrigeration system satisfies a second opening adjustment condition, the second opening adjustment condition being that each of the plurality of actual liquid outlet temperatures is greater than or equal to the set liquid outlet temperature, the maximum of the plurality of actual liquid outlet temperatures is greater than the sum of the set liquid outlet temperature and the liquid outlet accuracy, and at least one of the plurality of actual liquid outlet temperatures satisfies the liquid outlet accuracy condition; If the condition is satisfied, the operating opening of the bypass expansion valve is reduced, and after each reduction in the operating opening of the bypass expansion valve, the bypass expansion valve is controlled to maintain the reduced operating opening for one detection cycle until any one of the multiple actual liquid outlet temperatures obtained in the detection cycle meets the liquid outlet accuracy condition and the adjustment is stopped.

5. The control method of a refrigeration system according to any one of claims 2 to 4, characterized in that: After controlling the bypass expansion valve to operate at the set opening for a detection cycle and obtaining multiple actual liquid outlet temperatures within the detection cycle, the method further includes: When the relationship between the set liquid outlet temperature and the multiple actual liquid outlet temperatures indicates that the refrigeration system meets the abnormal reminder condition, abnormal reminder information is output, and the abnormal reminder information is used to remind the refrigeration system of abnormal operation.

6. The control method of the refrigeration system according to claim 5, characterized in that: The abnormal reminder condition is that the maximum of the multiple actual liquid outlet temperatures is greater than or equal to the sum of the set liquid outlet temperature and the liquid outlet accuracy, and the minimum is less than or equal to the difference between the set liquid outlet temperature and the liquid outlet accuracy.

7. The control method for a refrigeration system according to any one of claims 1 to 4, characterized in that: After determining the operating mode of the refrigeration system according to the set liquid outlet temperature, the method further includes: When it is determined that the refrigeration system is in the second working mode, the main expansion valve is opened and the bypass expansion valve is closed.

8. The control method for a refrigeration system according to any one of claims 1 to 4, characterized in that: The production instruction includes a production temperature gear, and determining a set liquid outlet temperature associated with the production instruction includes: A set liquid outlet temperature associated with the production temperature level is determined.

9. A refrigeration system, characterized in that: include: A first compressor, a first condenser, a main expansion valve and a load evaporator are sequentially connected to form a first circulation loop; a bypass flow path and a bypass expansion valve provided in the bypass flow path, wherein the bypass flow path is connected between the exhaust end of the first compressor and the inlet end of the load evaporator; as well as a liquid outlet temperature sensor, provided at the inlet end of the load evaporator, for detecting the liquid outlet temperature of the refrigeration system; as well as A controller is communicatively connected to the liquid outlet temperature sensor, the main expansion valve, and the bypass expansion valve, and the controller is capable of executing the control method according to any one of claims 1 to 8.

10. A testing device, characterized in that: The refrigeration system comprises a test terminal and the refrigeration system as claimed in claim 9, wherein the load evaporator is used to adjust the test temperature of the test terminal.

Images