Control method of electronic expansion valve of refrigerating system and refrigerating system

Abstract

The invention relates to a control method for an electronic expansion valve of a refrigerating system and the refrigerating system. The control method comprises the steps that the current production temperature of a load end, the current exhaust temperature of a first compressor and the current liquid outlet temperature of the refrigerating system are obtained; based on a first temperature gear where the current production temperature is located, a main electronic expansion valve is controlled to operate according to a first preset opening degree corresponding to the first temperature gear, and the opening degree of a cooling electronic expansion valve is adjusted in real time based on the relation between the current exhaust temperature and the target exhaust temperature; or, based on a second temperature gear where the current production temperature is located, the opening degree of the cooling electronic expansion valve is controlled to operate according to a second preset opening degree corresponding to the second temperature gear, and the opening degree of the main electronic expansion valve is adjusted in real time based on the relation between the current liquid outlet temperature and the target liquid outlet temperature; the main electronic expansion valve is arranged on a main loop of the refrigerating system, and the cooling electronic expansion valve is arranged on a bypass pipeline, used for cooling return air of the first compressor, of the refrigerating system.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigeration systems, and in particular to a control method for an electronic expansion valve of a refrigeration system and a refrigeration system. Background Art

[0002] The test equipment uses the refrigeration system as the cold source and the heating system as the heat source. It provides a stable temperature supply to the load end by means of cold-heat confrontation, so as to control the temperature of the electronic components through the load end, thereby performing low-temperature, normal-temperature and high-temperature tests on the electronic components.

[0003] When the load end is running under high temperature conditions, the heat load on the load end is large, and the refrigeration system needs to provide a certain amount of cooling capacity to counteract the heat load to control the temperature of the load end to a high temperature (such as 50℃-175℃). However, at this time, the refrigerant in the refrigeration system absorbs a large amount of heat, which increases the return air temperature of the compressor, and then causes the exhaust temperature of the compressor to increase and exceed the safe operating temperature of the compressor, which brings inconvenience to the test.

[0004] In order to avoid compressor exhaust overheating, part of the throttled refrigerant is allowed to flow to the compressor return air end through a bypass line to reduce the return air temperature, thereby achieving the purpose of reducing the exhaust temperature. However, the traditional control method causes the refrigeration system to be unable to exert its maximum refrigeration capacity under some high temperature conditions. Summary of the invention

[0005] Based on this, it is necessary to provide a control method for an electronic expansion valve of a refrigeration system and a refrigeration system to ensure that the refrigeration system can exert its maximum refrigeration capacity under various high temperature conditions in order to address the above problems.

[0006] A control method for an electronic expansion valve of a refrigeration system, comprising:

[0007] Obtaining the current production temperature of the load end, the current exhaust temperature of the first compressor, and the current liquid outlet temperature of the refrigeration system;

[0008] Based on the first temperature range where the current production temperature is located, the main electronic expansion valve is controlled to operate according to the first preset opening corresponding to the first temperature range, and the opening of the cooling electronic expansion valve is adjusted in real time based on the relationship between the current exhaust temperature and the target exhaust temperature; or, based on the second temperature range where the current production temperature is located, the opening of the cooling electronic expansion valve is controlled to operate according to the second preset opening corresponding to the second temperature range, and the opening of the main electronic expansion valve is adjusted in real time based on the relationship between the current liquid outlet temperature and the target liquid outlet temperature;

[0009] The main electronic expansion valve is arranged on the main circuit of the refrigeration system, and the cooling electronic expansion valve is arranged on the bypass pipeline of the refrigeration system for cooling the return air of the first compressor.

[0010] In one of the embodiments, based on the first temperature level of the current production temperature, controlling the main electronic expansion valve to operate according to the first preset opening corresponding to the first temperature level, and adjusting the opening of the cooling electronic expansion valve in real time based on the relationship between the current exhaust temperature and the target exhaust temperature includes:

[0011] The first temperature level is a first temperature value, and the first preset opening ms% corresponding to each first temperature value Ts satisfies the relationship:

[0012] ms%=(mh%-ml%)*(Ts-Th) / (TL-Th)+ml%;

[0013] The mh% is the first preset opening corresponding to the lowest preset temperature TL, and the ml% is the first preset opening corresponding to the highest preset temperature Th.

[0014] In one of the embodiments, based on the first temperature level of the current production temperature, controlling the main electronic expansion valve to operate according to the first preset opening corresponding to the first temperature level, and adjusting the opening of the cooling electronic expansion valve in real time based on the relationship between the current exhaust temperature and the target exhaust temperature includes:

[0015] When the current exhaust temperature is lower than the lower limit of the target exhaust temperature, the opening of the cooling electronic expansion valve is reduced; when the current exhaust temperature is higher than the upper limit of the target exhaust temperature, the opening of the cooling electronic expansion valve is increased.

[0016] In one embodiment, based on the second temperature level of the current production temperature, controlling the opening of the cooling electronic expansion valve to operate according to the second preset opening corresponding to the second temperature level, and adjusting the opening of the main electronic expansion valve in real time based on the relationship between the current liquid outlet temperature and the target liquid outlet temperature includes:

[0017] The second preset opening corresponding to each of the second temperature levels is:

[0018] In the second temperature range, the exhaust temperature of the first compressor is controlled to an opening degree corresponding to the upper and lower limits of the target exhaust temperature.

[0019] In one embodiment,

[0020] When the current liquid outlet temperature is within the upper and lower limits of the target liquid outlet temperature, and the current exhaust temperature is greater than a first preset exhaust temperature, it is determined whether the current exhaust temperature is within the upper and lower limits of the target exhaust temperature; the first preset exhaust temperature is less than the lower limit of the target exhaust temperature;

[0021] If so, the second preset opening is controlled to remain unchanged.

[0022] In one embodiment,

[0023] If the current exhaust temperature is greater than the upper limit of the target exhaust temperature, the adjustment of the second preset opening degree A′ satisfies the relationship:

[0024]

[0025] The C is for each second temperature level to control the opening corresponding to the exhaust temperature of the first compressor within the upper and lower limits of the first preset exhaust temperature, and the T C is the first preset exhaust temperature, the T A is the target exhaust temperature, T is the current exhaust temperature, and A is the opening corresponding to controlling the exhaust temperature of the first compressor in each second temperature gear within the upper and lower limits of the target exhaust temperature.

[0026] In one embodiment,

[0027] If the current exhaust temperature is less than the lower limit of the target exhaust temperature, the adjustment of the second preset opening degree A′ satisfies the relationship:

[0028]

[0029] The B is for each second temperature level to control the opening degree corresponding to the exhaust temperature of the first compressor within the upper and lower limits of the second preset exhaust temperature, and the T B is the second preset exhaust temperature, the T A is the target exhaust temperature, T is the current exhaust temperature, and A is the opening corresponding to controlling the exhaust temperature of the first compressor in each second temperature gear within the upper and lower limits of the target exhaust temperature.

[0030] In one embodiment, based on the second temperature level of the current production temperature, controlling the opening of the cooling electronic expansion valve to operate according to the second preset opening corresponding to the second temperature level, and adjusting the opening of the main electronic expansion valve in real time based on the relationship between the current liquid outlet temperature and the target liquid outlet temperature includes:

[0031] When the current liquid outlet temperature is lower than the lower limit of the target liquid outlet temperature, the opening of the main electronic expansion valve is increased; when the current liquid outlet temperature is higher than the upper limit of the target liquid outlet temperature, the opening of the main electronic expansion valve is reduced.

[0032] In one of the embodiments, based on the first temperature range where the current production temperature is located, the main electronic expansion valve is controlled to operate according to the first preset opening corresponding to the first temperature range, and the opening of the cooling electronic expansion valve is adjusted in real time based on the relationship between the current exhaust temperature and the target exhaust temperature; or, based on the second temperature range where the current production temperature is located, the opening of the cooling electronic expansion valve is controlled to operate according to the second preset opening corresponding to the second temperature range, and the opening of the main electronic expansion valve is adjusted in real time based on the relationship between the current liquid outlet temperature and the target liquid outlet temperature, before the step, further includes:

[0033] Controlling the main electronic expansion valve to operate at a first initial opening for a first preset time period;

[0034] When the current production temperature is greater than the lowest preset temperature and the current exhaust temperature is greater than the third preset exhaust temperature, the cooling electronic expansion valve is opened and operates at the second initial opening; the third preset exhaust temperature is less than the target exhaust temperature;

[0035] Among them, the second initial opening is when the load end is at the highest preset temperature and the opening of the main electronic expansion valve is at the opening corresponding to the highest preset temperature, so that the exhaust temperature of the first compressor is within the upper and lower limits of the target exhaust temperature, and the opening of the cooling electronic expansion valve is controlled.

[0036] A refrigeration system, the refrigeration system being controlled by the control method of the refrigeration system electronic expansion valve as described above, comprising:

[0037] A first compressor, a first condenser, a main electronic expansion valve and a first evaporator are sequentially connected to form a main loop, wherein the first evaporator serves as a load end or is used for heat exchange with the load end;

[0038] a bypass line, one end of which is in communication with a portion of the main circuit located between an output end of the first condenser and an input end of the main electronic expansion valve, and the other end of which is in communication with a portion of the main circuit located between an output end of the first evaporator and an input end of the first compressor;

[0039] The temperature-reducing electronic expansion valve is arranged on the bypass pipeline.

[0040] In the above-mentioned refrigeration system and control method of the electronic expansion valve of the refrigeration system, the opening of the cooling electronic expansion valve is adjustable. The two electronic expansion valves cooperate with each other to ensure that the load end operates stably within a preset temperature range. At the same time, it can also prevent the exhaust temperature of the first compressor from being too high or too low when the temperature of the load end is stable. Compared with the method of adjusting the flow rate of the refrigerant in the bypass line by a capillary tube in the prior art, the refrigeration system can exert its maximum refrigeration capacity under various high-temperature conditions (a variety of different high production temperatures). When testing high-power chips, the power level of the chip can continue to be improved, which is beneficial to the development of testing equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic diagram of a refrigeration system provided in one embodiment of the present application;

[0042] Figure 2 A schematic diagram of a refrigeration system provided in another embodiment of the present application;

[0043] Figure 3 A flow chart of a method for controlling an electronic expansion valve of a refrigeration system provided in one embodiment of the present application;

[0044] Figure 4 A flow chart of a method for controlling an electronic expansion valve of a refrigeration system provided by another embodiment of the present application;

[0045] Figure 5 A flow chart of a method for controlling an electronic expansion valve of a refrigeration system provided by another embodiment of the present application;

[0046] Figure 6 A flowchart of a method for controlling an electronic expansion valve in a refrigeration system provided in yet another embodiment of the present application.

[0047] Description of reference numerals:

[0048] 100. Refrigeration system; 10. First compressor; 20. First condenser; 30. Main electronic expansion valve; 40. First evaporator; 50. Cooling electronic expansion valve; 60. Second compressor; 70. Second condenser; 80. Throttle valve; 90. Second evaporator; 110. Second temperature sensor; 120. Third temperature sensor; A. Main circuit; B. Bypass line; C. Refrigerant circuit. DETAILED DESCRIPTION

[0049] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0050] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0051] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0052] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0054] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0055] As described in the background technology: the traditional control method causes the refrigeration system to be unable to exert its maximum refrigeration capacity under some high temperature conditions.

[0056] The applicant has found that the root cause of the above problems is that in the traditional technology, a solenoid valve and a capillary tube are set on the bypass line, and the flow rate of the refrigerant in the bypass line is controlled by the solenoid valve and the capillary tube, which results in the length and specification of the capillary tube used needing to meet the load end's requirements for the highest temperature condition (such as 175°C) to ensure that the exhaust temperature of the compressor does not exceed the temperature under this condition, so that the compressor operates within a safe range. However, for other high-temperature conditions (such as 50°C-150°C), the flow rate of the refrigerant bypassed by the capillary tube is too much, exceeding the required flow rate to reduce the return air temperature, resulting in more refrigerant being bypassed, and the refrigeration system cannot exert its maximum refrigeration capacity under these conditions, which in turn results in the inability to continue to increase the power level of the tested electronic components when testing high-power electronic components, limiting the development of test equipment.

[0057] In order to solve the above problems, an embodiment of the present application provides a refrigeration system, which cooperates with a heating system to control the temperature of the load end. The load end is used as the user end of the temperature-controlled electronic component, and is used to exchange heat with the electronic component so that the temperature of the electronic component is maintained within a preset temperature range. In a specific embodiment, the electronic component is a chip. Of course, in other embodiments, the type of electronic component is not limited.

[0058] The following introduces the refrigeration system provided by the present application by taking the electronic component being a chip as an example, but this introduction is only for example and does not limit the protection scope of the present application.

[0059] See also Figure 1The refrigeration system 100 includes a first compressor 10, a first condenser 20, a main electronic expansion valve 30 and a first evaporator 40. The first compressor 10, the first condenser 20, the main electronic expansion valve 30 and the first evaporator 40 are connected in sequence to form a main loop A. When the main loop A is working, the first compressor 10 inhales the refrigerant gas output from the output end of the first evaporator 40, and after compression and work, the refrigerant is discharged through its exhaust end and enters the first condenser 20. When the refrigerant passes through the first condenser 20, it is condensed by the first condenser 20, and after throttling and reducing the pressure by the main electronic expansion valve 30, it flows into the first evaporator 40, and finally flows from the output end of the first evaporator 40 to the first compressor 10 again, and the cycle repeats.

[0060] Optionally, the refrigeration system 100 also includes a refrigerant module, which exchanges heat with the main circuit A through the first evaporator 40 to provide a refrigerant to the load end circulation, and when the refrigerant passes through the load end, the temperature of the load end is reduced. Optionally, the first evaporator 40 is a dual-channel heat exchanger, one channel of which is part of the main circuit A, and the other channel is part of the refrigerant circuit C of the refrigerant module. At the same time, the load end is also provided with a heater, which can heat the load end to increase the temperature of the load end. Through this cold and heat confrontation method, the temperature of the load end is maintained within a preset temperature range to control the temperature of the chip.

[0061] In some other embodiments, the first evaporator 40 can also be used directly as a load end. In this case, when the heater is provided in the first evaporator 40, the temperature of the first evaporator 40 is maintained within a preset range through cooling resistance to control the temperature of the chip.

[0062] Continue reading Figure 1 The refrigeration system 100 further includes a bypass line B, one end of which is connected to a portion of the main circuit A between the output end of the first condenser 20 and the input end of the main electronic expansion valve 30, and the other end of which is connected to a portion of the main circuit A between the output end of the first evaporator 40 and the input end of the first compressor 10. The refrigeration system 100 further includes a temperature-reducing electronic expansion valve 50, which is disposed on the bypass line B. The opening of the temperature-reducing electronic expansion valve 50 is adjustable to adjust the flow rate of the refrigerant in the bypass line B.

[0063] In the above arrangement, the opening of the cooling electronic expansion valve 50 is adjustable, and the two electronic expansion valves (including the main electronic expansion valve 30 and the cooling electronic expansion valve 50) cooperate with each other to ensure that the load end operates stably within the preset temperature range. At the same time, it can also prevent the exhaust temperature of the first compressor 10 from being too high or too low when the temperature of the load end is stable. Compared with the method of adjusting the flow rate of the refrigerant in the bypass line B by a capillary tube in the prior art, the refrigeration system 100 can exert its maximum refrigeration capacity under various high temperature conditions (a variety of high production temperatures), and can continue to improve the power level of the chip when testing high-power chips, which is beneficial to the development of testing equipment.

[0064] In some embodiments, see Figure 3 , the refrigeration system 100 also includes a cooling module, which is used to cool the first condenser 20. Specifically, the cooling module includes a second compressor 60, a second condenser 70, a throttle valve 80 and a second evaporator 90, and the first condenser 20 and the second evaporator 90 are integrated into one to form an evaporative condenser. The second compressor 60, the second condenser 70, the throttle valve 80 and the second evaporator 90 are connected in sequence to form a cooling circuit, and the cooling circuit exchanges heat with the main circuit A through the evaporative condenser. At this time, the cooling circuit serves as a high-temperature refrigeration circuit of the refrigeration system 100, and the main circuit A serves as a low-temperature refrigeration circuit of the refrigeration system 100. The refrigeration system 100 is a two-stage cascade refrigeration system 100.

[0065] It is conceivable that in some other embodiments, the arrangement of the cooling module is not limited. For example, the cooling module may also include at least two cooling circuits for sequential heat exchange, and in this case, the refrigeration system 100 forms a multi-stage (more than two-stage) refrigeration system.

[0066] See also Figure 3 Another embodiment of the present application further provides a control method for an electronic expansion valve of a refrigeration system, which is used to control the above refrigeration system 100, including:

[0067] S110: Acquire the current production temperature of the load end, the current exhaust temperature of the first compressor 10 , and the current liquid outlet temperature of the refrigeration system 100 .

[0068] The current production temperature of the load end is the actual measured temperature of the load end at the current moment. Optionally, the load end is provided with a first temperature sensor, and the first temperature sensor can detect the temperature of the load end in real time to obtain the current production temperature.

[0069] The current exhaust temperature of the first compressor 10 is the actual temperature at the exhaust end of the first compressor 10 at the current moment. Optionally, the exhaust end of the first compressor 10 is provided with a second temperature sensor 110, which can detect the temperature of the exhaust end of the first compressor 10 in real time to obtain the current exhaust temperature.

[0070] The current outlet liquid temperature of the refrigeration system 100 is the actual measured temperature of the refrigerant at the input end of the first evaporator 40 after being throttled by the main electronic expansion valve 30. Optionally, a third temperature sensor 120 is provided between the main electronic expansion valve 30 and the first evaporator 40, and the third temperature sensor 120 can detect the outlet liquid temperature of the refrigeration system 100 in real time to obtain the current outlet liquid temperature.

[0071] S120: Based on the first temperature level of the current production temperature, the main electronic expansion valve 30 is controlled to operate according to the first preset opening corresponding to the first temperature level, and the opening of the cooling electronic expansion valve 50 is adjusted in real time based on the relationship between the current exhaust temperature and the target exhaust temperature; or, based on the second temperature level of the current production temperature, the opening of the cooling electronic expansion valve 50 is controlled to operate according to the second preset opening corresponding to the second temperature level, and the opening of the main electronic expansion valve 30 is adjusted in real time based on the relationship between the current liquid outlet temperature and the target liquid outlet temperature.

[0072] The production temperature is divided into a plurality of different first temperature levels, and different first temperature levels cover different temperature values. For the main electronic expansion valve 30, each first temperature level corresponds to a first preset opening, and different first temperature levels correspond to different first preset openings. Optionally, the first preset opening corresponding to each first temperature level can be obtained by experiment, or by experience.

[0073] It should be noted that the first temperature range can be a temperature interval, which includes multiple temperature values, and the first temperature range can also be a specific temperature value. When the first temperature range is a temperature range, all temperatures in the temperature range correspond to the same first preset opening. When the first temperature range is a temperature value, each temperature value corresponds to a first preset opening.

[0074] After the first temperature level of the current production temperature is determined, the main electronic expansion valve 30 operates according to the first preset opening corresponding to the first temperature level to ensure that the load end has a small temperature fluctuation, which is convenient for temperature control of the chip. The opening of the cooling electronic expansion valve 50 is adjusted in real time based on the relationship between the current exhaust temperature and the target exhaust temperature to avoid the exhaust temperature at the exhaust end of the first compressor 10 being too high or too low, thereby ensuring the stable operation of the refrigeration system 100.

[0075] The target exhaust temperature is a temperature at which the exhaust temperature of the compressor is controlled not to be too high or too low, and is a temperature at which the first compressor 10 operates safely. At the same time, at this temperature, the refrigeration system 100 can exert its maximum refrigeration capacity.

[0076] The current production temperature is divided into a plurality of different second temperature levels, and different second temperature levels cover different temperature values. For the cooling electronic expansion valve 50, each second temperature level corresponds to a second preset opening, and different second temperature levels correspond to different second preset openings. Optionally, the second preset opening corresponding to each second temperature level is obtained by experiment, or the second preset opening corresponding to each second temperature level can be obtained by experience.

[0077] It should be noted that the second temperature range can be a temperature range, which includes multiple temperature values, and the second temperature range can also be a specific temperature value. When the second temperature range is a temperature range, all temperatures in the temperature range correspond to the same second preset opening. When the second temperature range is a temperature value, each temperature value corresponds to a second preset opening.

[0078] It should also be noted that the settings of the first temperature level and the second temperature level may be the same or different, and are not limited here.

[0079] After the second temperature range of the current production temperature is determined, the cooling electronic expansion valve 50 operates according to the second preset opening corresponding to the second temperature range to ensure that the exhaust temperature at the exhaust end of the first compressor 10 has a small fluctuation, so that the exhaust temperature of the first compressor 10 is not too high or too low. The opening of the main electronic expansion valve 30 is adjusted based on the relationship between the current liquid outlet temperature and the target liquid outlet temperature to avoid the situation where the current liquid outlet temperature is too high or too low, resulting in excessive temperature fluctuations at the load end.

[0080] The target liquid outlet temperature is the liquid outlet temperature that the refrigeration system 100 is expected to achieve, and at this liquid outlet temperature, the temperature at the load end will not fluctuate greatly.

[0081] The control method of the electronic expansion valve of the refrigeration system described above controls one of the main electronic expansion valve 30 and the cooling electronic expansion valve 50 to operate at a preset opening corresponding to the temperature range according to the temperature range of the current production temperature, and the other electronic expansion valve is adjusted according to the relationship between the current temperature (current exhaust temperature or current liquid outlet temperature) and the target temperature (target exhaust temperature or target liquid outlet temperature). In this way, the two electronic expansion valves cooperate with each other to ensure that the load end operates stably within the preset temperature range, and can also prevent the exhaust temperature of the first compressor 10 from being too high or too low when the load end temperature is stable. Compared with the method of adjusting the flow rate of the refrigerant in the bypass line B by a capillary tube in the prior art, the refrigeration system 100 can exert the maximum refrigeration capacity under various high temperature conditions (under various high production temperatures), and can continue to improve the power level of the chip when testing high-power chips, which is beneficial to the development of testing equipment.

[0082] Furthermore, before S120, the method further includes the following steps:

[0083] The main electronic expansion valve 30 is controlled to operate at a first initial opening degree for a first preset time period.

[0084] In the initial stage after the refrigeration system 100 is started, the main electronic expansion valve 30 is controlled to operate at a first initial opening for a first preset time. After the parameters of the various structures of the refrigeration system 100 are fixed, the first initial opening is generally a fixed value that matches these parameters. The first preset time enables the refrigeration system 100 to transition from the initial stage to the normal operation stage. The first preset time can be set as needed, such as in some specific embodiments, the first preset time is set to 2 minutes.

[0085] If the current production temperature is greater than the lowest preset temperature and the current exhaust temperature is greater than the third preset exhaust temperature, the cooling electronic expansion valve 50 is opened and operated at the second initial opening. Optionally, the cooling electronic expansion valve 50 is opened and operated at the second initial opening for a second preset time. The third preset exhaust temperature is less than the target exhaust temperature. The second preset time can be set as needed, such as in some specific embodiments, the second preset time is set to 2 minutes.

[0086] Among them, the second initial opening is when the load end is at the highest preset temperature and the opening of the main electronic expansion valve 30 is at the opening corresponding to the highest preset temperature, so that the exhaust temperature of the first compressor 10 is within the upper and lower limits of the target exhaust temperature, and the opening of the cooling electronic expansion valve 50 is controlled.

[0087] When the current production temperature is greater than the lowest preset temperature, and the current exhaust temperature is greater than the third preset exhaust temperature, it proves that the load end is operating in a high temperature condition, and the exhaust temperature of the first compressor 10 is relatively high. At this time, the cooling electronic expansion valve 50 is opened to cool the exhaust of the first compressor 10. Since the third preset exhaust temperature is lower than the target exhaust temperature, the cooling electronic expansion valve 50 is started at this temperature to avoid the situation where the exhaust temperature of the first compressor 10 rises instantaneously and cannot be cooled in time. At the same time, when the second initial opening is when the load end is at the highest preset temperature and the opening of the main electronic expansion valve 30 is at the opening corresponding to the highest preset temperature, so that the exhaust temperature of the first compressor 10 is within the upper and lower limits of the target exhaust temperature, the opening of the cooling electronic expansion valve 50 is controlled. In this case, the opening of the cooling electronic expansion valve 50 is relatively large to avoid the exhaust of the first compressor 10 from overheating.

[0088] It is conceivable that in other embodiments, the second initial opening can also be set in other ways, which are not limited here.

[0089] It should be noted that in step S120, the opening of the main electronic expansion valve 30 is adjusted based on the first initial opening, and the opening of the cooling electronic expansion valve 50 is adjusted based on the second initial opening. When the main electronic expansion valve 30 needs to operate at the first preset opening, the main electronic expansion valve 30 can directly transition from the first initial opening to the first preset opening; when the cooling electronic expansion valve 50 needs to operate at the second preset opening, the cooling electronic expansion valve 50 directly transitions from the second initial opening to the second preset opening.

[0090] In the first embodiment, see Figure 4 , S120 includes step S121:

[0091] The first temperature level is the first temperature value, and the first preset opening ms% corresponding to each first temperature value Ts satisfies the relationship:

[0092] ms%=(mh%-ml%)*(Ts-Th) / (TL-Th)+ml%;

[0093] Wherein, mh% is the first preset opening corresponding to the lowest preset temperature TL, and ml% is the first preset opening corresponding to the highest preset temperature Th. In some specific implementations, TL=50°C, Th=175°C.

[0094] The lowest preset temperature TL and the highest preset temperature Th are the lowest production temperature value and the highest production temperature value at the load end when the cooling electronic expansion valve 50 needs to be opened to cool the return air at the return air end of the first compressor 10. The first preset opening corresponding to the lowest preset temperature value TL is mh%, and the first preset opening corresponding to the highest preset temperature Th is ml%. According to the linear relationship ms%=(mh%-ml%)*(Ts-Th) / (TL-Th)+ml%, the first preset opening ms% corresponding to each first temperature value Ts can be obtained. By determining the first temperature level of the current production temperature, it can be known at what opening the main electronic expansion valve 30 is fixed to operate.

[0095] It is understandable that in some other embodiments, the first temperature range can also be set as a temperature interval. For example, in some specific embodiments, the temperature intervals are set to [50°C, 85°C), [85°C, 105°C), [105°C, 125°C), [125°C, 150°C), [150°C, 175°C), [175°C,), and in each temperature interval, the main electronic expansion valve 30 has a corresponding first preset opening.

[0096] In this embodiment, S121 includes:

[0097] When the current exhaust temperature is lower than the lower limit of the target exhaust temperature, the opening of the cooling electronic expansion valve 50 is reduced; when the current exhaust temperature is higher than the upper limit of the target exhaust temperature, the opening of the cooling electronic expansion valve 50 is increased. Set the target exhaust temperature to T A , then the current exhaust temperature is less than T A -ΔT A When the opening of the cooling electronic expansion valve 50 is reduced, the current exhaust temperature is greater than T A +ΔT A When the temperature drops to 0, the opening of the cooling electronic expansion valve 50 is increased. In some specific embodiments, T A At 100°C, ΔT A is 2°C, the upper limit of the target exhaust temperature is 100°C+2°C=102°C. In some other specific embodiments, for T A and ΔT A There is no limitation.

[0098] When the current exhaust temperature is less than the lower limit of the target exhaust temperature, it proves that the current exhaust temperature is low. Reducing the opening of the cooling electronic expansion valve 50 can reduce the flow of the refrigerant in the bypass line B, so that the refrigerant flowing to the return air end of the first compressor 10 through the bypass line B is reduced, thereby increasing the exhaust temperature of the first compressor 10, so that the exhaust temperature of the first compressor 10 is within the upper and lower limits of the target exhaust temperature. When the current exhaust temperature is greater than the upper limit of the target exhaust temperature, it proves that the current exhaust temperature is high. Increasing the opening of the cooling electronic expansion valve 50 can increase the flow of the refrigerant in the bypass line B, so that the refrigerant flowing to the return air end of the first compressor 10 through the bypass line B is increased, thereby reducing the exhaust temperature of the first compressor 10, so that the exhaust temperature of the first compressor 10 is within the upper and lower limits of the target exhaust temperature.

[0099] It should be noted that the opening of the cooling electronic expansion valve 50 is not limited to increase or decrease each time, and can be performed according to the first preset value. When the current exhaust temperature is within the upper and lower limits of the target exhaust temperature, the opening of the cooling electronic expansion valve 50 is not adjusted and remains unchanged.

[0100] In the second embodiment, S120 includes S122:

[0101] The second preset opening corresponding to each second temperature level is:

[0102] In the second temperature range, the exhaust temperature of the first compressor 10 is controlled to be within the opening degree corresponding to the upper and lower limits of the target exhaust temperature.

[0103] In some specific implementations, the second temperature range is a temperature range, such as [50°C, 85°C), [85°C, 105°C), [105°C, 125°C), [125°C, 150°C), [150°C, 175°C), [175°C,). In the above 6 temperature ranges, the second preset opening is A1%, A2%, A3%, A4%, A5%, A6% respectively. It is conceivable that in some other implementations, the second temperature range can also be set to a temperature value, and each temperature value corresponds to a second preset opening, which is not limited here.

[0104] In this embodiment, S122 further includes:

[0105] When the current liquid outlet temperature is less than the lower limit of the target liquid outlet temperature, the opening of the main electronic expansion valve 30 is increased; when the current liquid outlet temperature is greater than the upper limit of the target liquid outlet temperature, the opening of the main electronic expansion valve 30 is reduced. The target liquid outlet temperature is set to t0, and when the current liquid outlet temperature is less than t0-Δt0, the opening of the main electronic expansion valve 30 is increased, and when the current liquid outlet temperature is greater than t0+Δt0, the opening of the main electronic expansion valve 30 is reduced. In some specific implementations, Δt0 is set to 0.5°C.

[0106] When the current liquid outlet temperature is less than the lower limit of the target liquid outlet temperature, it proves that the current liquid outlet temperature is low. Increasing the opening of the main electronic expansion valve 30 can increase the current liquid outlet temperature so that the current liquid outlet temperature is within the upper and lower limits of the target liquid outlet temperature. When the current liquid outlet temperature is greater than the target liquid outlet temperature, it proves that the current liquid outlet temperature is high. Reducing the opening of the main electronic expansion valve 30 can reduce the current liquid outlet temperature so that the current liquid outlet temperature is within the upper and lower limits of the target liquid outlet temperature.

[0107] It should be noted that the opening of the main electronic expansion valve 30 is not limited to increase or decrease each time, and can be performed according to the second preset value. When the current outlet liquid temperature is within the upper and lower limits of the target outlet liquid temperature, the opening of the main electronic expansion valve 30 is not adjusted and remains unchanged.

[0108] In the third embodiment, the difference from the second embodiment is that Figure 6 , the control method of the electronic expansion valve of the refrigeration system also includes:

[0109] Step S131 includes determining whether the current liquid outlet temperature is within the upper and lower limits of the target liquid outlet temperature, and the current exhaust temperature is greater than the first preset exhaust temperature, and step S132 includes determining whether the current exhaust temperature is within the upper and lower limits of the target exhaust temperature. The first preset exhaust temperature is less than the lower limit of the target exhaust temperature. Optionally, the first preset exhaust temperature is greater than the third preset exhaust temperature.

[0110] If so, the process includes step S133 of controlling the second preset opening to remain unchanged.

[0111] When the current liquid outlet temperature is within the upper and lower limits of the target exhaust temperature, and the current exhaust temperature is greater than the first preset exhaust temperature, it is proved that the current liquid outlet temperature meets the requirements, and the current exhaust temperature is close to the target exhaust temperature. If the current exhaust temperature is further within the upper and lower limits of the target exhaust temperature, it is proved that the current exhaust temperature meets the requirements, and there is no need to adjust the second preset opening.

[0112] The above setting, on the basis of the second embodiment, judges the relationship between the current exhaust temperature and the target exhaust temperature to determine whether the second preset opening needs to be adjusted, thereby ensuring more precise control of the opening of the cooling electronic expansion valve 50, so that the refrigeration system 100 can exert its maximum refrigeration capacity under each high temperature condition.

[0113] In some specific implementations, when the current liquid outlet temperature is within the upper and lower limits of the target liquid outlet temperature, and the current exhaust temperature is greater than the first preset exhaust temperature, the refrigeration system runs for a third preset time, and then determines whether the current exhaust temperature is within the upper and lower limits of the target exhaust temperature. The third preset time can be set as needed, such as in some specific implementations, the third preset time is set to 5 minutes.

[0114] Step S134 includes if the current exhaust temperature is greater than the upper limit of the target exhaust temperature, the second preset opening degree A′ is adjusted to satisfy the relationship:

[0115]

[0116] C controls the opening degree corresponding to the exhaust temperature of the first compressor 10 within the upper and lower limits of the first preset exhaust temperature for each second temperature level, T C is the first preset exhaust temperature, T A is the target exhaust temperature, T is the current exhaust temperature, and A is the opening degree corresponding to controlling the exhaust temperature of the first compressor 10 in each second temperature gear within the upper and lower limits of the target exhaust temperature.

[0117] If the current exhaust temperature is greater than the upper limit of the target exhaust temperature, it means that the current exhaust temperature is relatively high. The second preset opening is adjusted by the above formula so that the current exhaust temperature is within the upper and lower limits of the target exhaust temperature.

[0118] Optionally, there are 6 second temperature levels, T A The second preset openings corresponding to the six second temperature levels are A1%, A2%, A3%, A4%, A5%, and A6%. C The second preset openings corresponding to the six second temperature levels are C1%, C2%, C3%, C4%, C5%, and C6% respectively.

[0119] When the target production temperature is at the first second temperature level, the adjustment of the second preset opening A′ satisfies the relationship:

[0120]

[0121] It can be imagined that, according to the different second temperature levels, the C value and the A value in the above formula can be changed accordingly.

[0122] In some specific embodiments, the six second temperature levels are [50°C, 85°C), [85°C, 105°C), [105°C, 125°C), [125°C, 150°C), [150°C, 175°C), [175°C, ), T A At 100°C, T C At 95℃.

[0123] It is conceivable that in some other implementations, the number of the second temperature levels is not limited, and each second temperature level may also be set in other ways, and T A and T C The value of is not limited.

[0124] Further, step S135 includes if the current exhaust temperature is less than the lower limit of the target exhaust temperature, the second preset opening degree A′ is adjusted to satisfy the relationship:

[0125]

[0126] B controls the opening degree corresponding to the exhaust temperature of the first compressor 10 within the upper and lower limits of the second preset exhaust temperature for each second temperature level, T B is the second preset exhaust temperature, T A is the target exhaust temperature, T is the current exhaust temperature, and A is the opening corresponding to the exhaust temperature of the first compressor 10 in each second temperature level controlled within the upper and lower limits of the target exhaust temperature;

[0127] The second preset exhaust temperature is greater than the upper limit of the target exhaust temperature.

[0128] If the current exhaust temperature is lower than the lower limit of the target exhaust temperature, it means that the current exhaust temperature is relatively low. The second preset opening is adjusted by the above formula so that the current exhaust temperature is within the upper and lower limits of the target exhaust temperature.

[0129] Optionally, there are 6 second temperature levels, T A The second preset openings corresponding to the six second temperature levels are A1%, A2%, A3%, A4%, A5%, and A6%. B The second preset openings corresponding to the six second temperature levels are B1%, B2%, B3%, B4%, B5%, and B6% respectively.

[0130] When the target production temperature is at the first second temperature level, the adjustment of the second preset opening A′ satisfies the relationship:

[0131]

[0132] It is conceivable that, depending on the second temperature level, the C value and the B value in the above formula are changed accordingly.

[0133] In some specific embodiments, the six second temperature levels are [50°C, 85°C), [85°C, 105°C), [105°C, 125°C), [125°C, 150°C), [150°C, 175°C), [175°C, ), T A At 100°C, T B At 105℃.

[0134] Of course, in some other implementations, the number of the second temperature levels is not limited, and each second temperature level may also be set in other ways, and T A and T B The value of is not limited.

[0135] It is understandable that after the cooling electronic expansion valve 50 continues to operate for the fourth preset time according to the opening A', if the current exhaust temperature deviates from the upper and lower limits of the target exhaust temperature, the above logic is executed according to the detected current exhaust temperature. The fourth preset time can be set as needed, such as in some specific embodiments, the fourth preset time is set to 10 minutes.

[0136] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described 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.

[0137] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A control method for an electronic expansion valve in a refrigeration system, characterized in that: include: Acquiring the current production temperature of the load end, the current exhaust temperature of the first compressor (10), and the current liquid outlet temperature of the refrigeration system; Based on the first temperature level at which the current production temperature is located, controlling the main electronic expansion valve (30) to operate according to a first preset opening corresponding to the first temperature level, and adjusting the opening of the cooling electronic expansion valve (50) in real time based on the relationship between the current exhaust temperature and the target exhaust temperature; Alternatively, based on the second temperature range of the current production temperature, the opening of the cooling electronic expansion valve (50) is controlled to operate according to a second preset opening corresponding to the second temperature range, and the opening of the main electronic expansion valve (30) is adjusted in real time based on the relationship between the current liquid outlet temperature and the target liquid outlet temperature; The main electronic expansion valve (30) is arranged on the main circuit (A) of the refrigeration system, and the cooling electronic expansion valve (50) is arranged on a bypass pipeline (B) of the refrigeration system for cooling the return air of the first compressor (10).

2. The control method of the electronic expansion valve of the refrigeration system according to claim 1, characterized in that: Based on the first temperature level at which the current production temperature is located, controlling the main electronic expansion valve (30) to operate according to a first preset opening corresponding to the first temperature level, and adjusting the opening of the cooling electronic expansion valve (50) in real time based on the relationship between the current exhaust temperature and the target exhaust temperature comprises: The first temperature level is a first temperature value, and the first preset opening ms% corresponding to each first temperature value Ts satisfies the relationship: ms%=(mh%-ml%)*(Ts-Th) / (TL-Th)+ml%; The mh% is the first preset opening corresponding to the lowest preset temperature TL, and the ml% is the first preset opening corresponding to the highest preset temperature Th.

3. The control method of the electronic expansion valve of the refrigeration system according to claim 1, characterized in that: Based on the first temperature level at which the current production temperature is located, controlling the main electronic expansion valve (30) to operate according to a first preset opening corresponding to the first temperature level, and adjusting the opening of the cooling electronic expansion valve (50) in real time based on the relationship between the current exhaust temperature and the target exhaust temperature comprises: When the current exhaust temperature is lower than the lower limit of the target exhaust temperature, the opening of the cooling electronic expansion valve (50) is reduced; when the current exhaust temperature is higher than the upper limit of the target exhaust temperature, the opening of the cooling electronic expansion valve (50) is increased.

4. The control method of the electronic expansion valve of a refrigeration system according to claim 1, characterized in that: The step of controlling the opening of the cooling electronic expansion valve (50) to operate according to a second preset opening corresponding to the second temperature level based on the second temperature level of the current production temperature, and adjusting the opening of the main electronic expansion valve (30) in real time based on the relationship between the current liquid outlet temperature and the target liquid outlet temperature comprises: The second preset opening corresponding to each of the second temperature levels is: In the second temperature range, the exhaust temperature of the first compressor (10) is controlled to have an opening degree corresponding to an upper and lower limit range of the target exhaust temperature.

5. The control method of the electronic expansion valve of the refrigeration system according to claim 4, characterized in that: When the current liquid outlet temperature is within the upper and lower limits of the target liquid outlet temperature, and the current exhaust temperature is greater than a first preset exhaust temperature, it is determined whether the current exhaust temperature is within the upper and lower limits of the target exhaust temperature; the first preset exhaust temperature is less than the lower limit of the target exhaust temperature; If so, the second preset opening is controlled to remain unchanged.

6. The control method of the electronic expansion valve of a refrigeration system according to claim 5, characterized in that: If the current exhaust temperature is greater than the upper limit of the target exhaust temperature, the adjustment of the second preset opening degree A′ satisfies the relationship: The C is the opening corresponding to the exhaust temperature of the first compressor (10) within the upper and lower limits of the first preset exhaust temperature for each of the second temperature levels, and the T C is the first preset exhaust temperature, the T A is the target exhaust temperature, T is the current exhaust temperature, and (A) controls the opening degree corresponding to the exhaust temperature of the first compressor (10) within the upper and lower limits of the target exhaust temperature for each of the second temperature levels.

7. The control method of the electronic expansion valve of a refrigeration system according to claim 5, characterized in that: If the current exhaust temperature is less than the lower limit of the target exhaust temperature, the adjustment of the second preset opening degree A′ satisfies the relationship: The (B) controls the opening degree corresponding to the exhaust temperature of the first compressor (10) within the upper and lower limits of the second preset exhaust temperature for each of the second temperature levels, wherein the T B is the second preset exhaust temperature, the T A is the target exhaust temperature, T is the current exhaust temperature, and (A) controls the opening degree of the first compressor (10) corresponding to the exhaust temperature within the upper and lower limits of the target exhaust temperature for each second temperature level; Wherein, the second preset exhaust temperature is greater than the upper limit of the target exhaust temperature.

8. The control method of the electronic expansion valve of a refrigeration system according to claim 1, characterized in that: The step of controlling the opening of the cooling electronic expansion valve (50) to operate according to a second preset opening corresponding to the second temperature level based on the second temperature level of the current production temperature, and adjusting the opening of the main electronic expansion valve (30) in real time based on the relationship between the current liquid outlet temperature and the target liquid outlet temperature comprises: When the current liquid outlet temperature is lower than the lower limit of the target liquid outlet temperature, the opening of the main electronic expansion valve (30) is increased; when the current liquid outlet temperature is higher than the upper limit of the target liquid outlet temperature, the opening of the main electronic expansion valve (30) is reduced.

9. The control method of the electronic expansion valve of a refrigeration system according to any one of claims 1 to 8, characterized in that: Based on the first temperature level at which the current production temperature is located, the main electronic expansion valve (30) is controlled to operate according to a first preset opening corresponding to the first temperature level, and the opening of the cooling electronic expansion valve (50) is adjusted in real time based on the relationship between the current exhaust temperature and the target exhaust temperature; Alternatively, based on the second temperature range of the current production temperature, the opening of the cooling electronic expansion valve (50) is controlled to operate according to a second preset opening corresponding to the second temperature range, and before the step of adjusting the opening of the main electronic expansion valve (30) in real time based on the relationship between the current liquid outlet temperature and the target liquid outlet temperature, the method further includes: Controlling the main electronic expansion valve (30) to operate at a first initial opening degree for a first preset time period; When the current production temperature is greater than the lowest preset temperature and the current exhaust temperature is greater than a third preset exhaust temperature, the cooling electronic expansion valve (50) is opened and operates at a second initial opening; the third preset exhaust temperature is less than the target exhaust temperature; The second initial opening is when the load end is at a maximum preset temperature and the opening of the main electronic expansion valve (30) is at an opening corresponding to the maximum preset temperature, so that the exhaust temperature of the first compressor (10) is within the upper and lower limits of the target exhaust temperature, and the opening of the cooling electronic expansion valve (50) is controlled.

10. A refrigeration system, characterized in that: The refrigeration system is controlled by the control method of the electronic expansion valve of the refrigeration system according to any one of claims 1 to 9, comprising: A first compressor (10), a first condenser (20), a main electronic expansion valve (30) and a first evaporator (40) are sequentially connected to form a main circuit (A), wherein the first evaporator (40) serves as a load end or is used for heat exchange with the load end; a bypass line (B), one end of which is in communication with a portion of the main circuit (A) located between an output end of the first condenser (20) and an input end of the main electronic expansion valve (30), and the other end of which is in communication with a portion of the main circuit (A) located between an output end of the first evaporator (40) and an input end of the first compressor (10); The temperature-reducing electronic expansion valve (50) is arranged on the bypass pipeline (B).

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