Refrigeration System and Control Method for Segmented Refrigeration Cryogenic High and Low Temperature Chambers

Abstract

This application relates to a segmented refrigeration system and control method for cryogenic high and low temperature chambers. The segmented refrigeration system for cryogenic high and low temperature chambers controls the temperature and humidity of the chamber through a high-temperature stage refrigeration component and a low-temperature stage refrigeration component. When only the temperature of the chamber is controlled, only the high-temperature stage refrigeration component is activated, so that the actual temperature of the chamber reaches the set temperature. When both the temperature and humidity of the chamber are controlled, the high-temperature stage refrigeration component and the low-temperature stage refrigeration component are activated simultaneously as a cascade system, so that the actual temperature and humidity of the chamber reach the set values. The low-temperature stage refrigeration component does not need to cool down from the high-temperature environment, but only needs to control the temperature of the low-temperature cooling range, which greatly reduces the energy regulation ratio of the low-temperature stage refrigeration component and significantly reduces the overall cooling capacity of the chamber. Due to the existence of the cascade system, the operating power of the entire system is reduced.

Description

Technical Field

[0001] This application relates to the field of high and low temperature chamber technology, and in particular to a refrigeration system and control method for a segmented refrigeration cryogenic high and low temperature chamber. Background Technology

[0002] With the development of technology, the requirements for the performance and reliability of various automotive parts and electronic products are becoming increasingly stringent. In order to accelerate the research and development of related products, a large number of environmental performance tests are required. Therefore, there is an increasing demand for high and low temperature humidity test chambers that integrate high temperature testing, low temperature testing, high and low temperature testing and damp heat alternation testing.

[0003] Currently, high and low temperature humidity test chambers on the market are basically divided into low temperature ranges of -40℃ and -70℃. Those reaching below -70℃ are generally referred to as cryogenic high and low temperature chambers. Traditional cryogenic high and low temperature chambers typically employ a cascade system in their refrigeration system design, consisting of a high-temperature stage and a low-temperature stage. The evaporator in the low-temperature stage is located inside the chamber and is primarily responsible for controlling the internal low-temperature environment, working in conjunction with electric heating to control the temperature. Simultaneously, the high and low temperature chamber also needs to maintain humidity within a wide range within a certain temperature range. Therefore, it is also equipped with a dehumidifying tube evaporator and a humidifier. The dehumidifying tube evaporator is generally another parallel branch loop in the low-temperature stage cycle. This allows for independent control of both temperature and humidity, ensuring the required temperature and humidity levels of the high and low temperature test chamber are met.

[0004] Traditional cryogenic high and low temperature chambers often require a large refrigeration system capacity to achieve a certain cooling rate when cooling from a high-temperature environment to a low-temperature environment. However, the refrigeration capacity needed to maintain the low temperature environment is very small, perhaps less than 10% of the current configuration capacity. Therefore, when maintaining the low temperature, because it uses a fixed-frequency compressor, it is necessary to use hot gas bypass or simultaneous auxiliary heating to balance the excess refrigeration capacity, resulting in double energy waste and very low refrigeration efficiency. Furthermore, in the temperature range from the high-temperature environment to -30°C, which could be achieved by a single-stage compression system, a cascade system is used, with two compressors running simultaneously, resulting in high energy consumption and low refrigeration efficiency in existing high and low temperature chambers. Summary of the Invention

[0005] Therefore, it is necessary to provide a segmented refrigeration system and control method for cryogenic high and low temperature chambers, addressing the problems of high energy consumption and low refrigeration efficiency of existing high and low temperature chambers.

[0006] On one hand, this application provides a segmented refrigeration system for cryogenic high and low temperature chambers, comprising:

[0007] A low-temperature stage refrigeration assembly includes a low-temperature stage evaporator, a low-temperature stage compressor, a low-temperature stage oil separator, a low-temperature stage water-cooled precooler, an expansion tank, and a low-temperature stage gas-liquid separator. The outlet of the low-temperature stage compressor is connected to the inlet of the low-temperature stage oil separator, the outlet of the low-temperature stage oil separator is connected to the inlet of the low-temperature stage water-cooled precooler, the outlet of the low-temperature stage water-cooled precooler is connected to the inlet of the evaporator-condenser, the inlet of the expansion tank, and the inlet of the low-temperature stage gas-liquid separator, respectively. The outlet of the low-temperature stage gas-liquid separator is connected to the inlet of the low-temperature stage compressor, the inlet of the low-temperature stage evaporator is connected to the outlet of the evaporator-condenser, and the inlet of the low-temperature stage gas-liquid separator is connected to the outlet of the low-temperature stage evaporator, the outlet of the expansion tank, the outlet of the evaporator-condenser, and the outlet of the low-temperature stage water-cooled precooler, respectively.

[0008] A high-temperature stage refrigeration component is interconnected with the low-temperature stage refrigeration component. The high-temperature stage refrigeration component includes a high-temperature stage evaporator, a high-temperature stage compressor, a high-temperature stage oil separator, a high-temperature stage water-cooled condenser, a high-temperature stage liquid receiver, an evaporator-condenser, and a high-temperature stage gas-liquid separator. The outlet of the high-temperature stage compressor is connected to the inlet of the high-temperature stage oil separator. The outlet of the high-temperature stage oil separator is connected to the inlet of the high-temperature stage water-cooled condenser. The outlet of the high-temperature stage water-cooled condenser is connected to the inlet of the high-temperature stage liquid receiver. The outlet of the high-temperature stage liquid receiver is connected to the inlet of the evaporator-condenser. The outlet of the high-temperature stage compressor is connected to the inlet of the high-temperature stage gas-liquid separator. The outlet of the high-temperature stage gas-liquid separator is connected to the inlet of the high-temperature stage compressor. The inlet of the high-temperature stage gas-liquid separator is connected to the outlets of the evaporator-condenser, the high-temperature stage oil separator, the high-temperature stage evaporator, and the high-temperature stage liquid receiver, respectively. The outlet of the high-temperature stage liquid receiver is also connected to the inlet of the high-temperature stage evaporator.

[0009] When the required temperature of the high and low temperature chamber is in the high-temperature stage cooling range, only the high-temperature stage refrigeration component is activated to bring the actual temperature of the high and low temperature chamber to the required temperature. When the required temperature of the high and low temperature chamber is in the low-temperature stage cooling range, both the high-temperature stage refrigeration component and the low-temperature stage refrigeration component are activated to bring the actual temperature of the high and low temperature chamber to the required temperature.

[0010] On the other hand, this application also provides a control method for a segmented refrigeration system for cryogenic high and low temperature chambers, comprising:

[0011] Set the temperature threshold of the high and low temperature chamber, and define the high temperature stage cooling range and the low temperature stage cooling range; all temperature values ​​in the high temperature stage cooling range are greater than or equal to the temperature threshold, and all temperature values ​​in the low temperature stage cooling range are less than the temperature threshold.

[0012] Set the required temperature for the high and low temperature chamber;

[0013] Determine whether the required temperature of the high and low temperature chamber is greater than or equal to the temperature threshold.

[0014] If the required temperature of the high and low temperature chamber is greater than or equal to the temperature threshold, then the required temperature of the high and low temperature chamber is determined to be in the high temperature stage cooling range, and the high temperature stage refrigeration components are started until the actual temperature of the high and low temperature chamber reaches the required temperature.

[0015] If the required temperature of the high and low temperature chamber is less than the temperature threshold, then the required temperature of the high and low temperature chamber is determined to be in the low temperature stage cooling range. At the same time, the low temperature stage refrigeration components and the high temperature stage refrigeration components are started until the actual temperature of the high and low temperature chamber reaches the required temperature.

[0016] This application relates to a segmented refrigeration system and control method for cryogenic high and low temperature chambers. The segmented refrigeration system for cryogenic high and low temperature chambers controls the temperature and humidity of the chamber through a high-temperature stage refrigeration component working in conjunction with a low-temperature stage refrigeration component. When only the temperature of the chamber is controlled, only the high-temperature stage refrigeration component is activated, so that the actual temperature of the chamber reaches the set temperature. When both the temperature and humidity of the chamber are controlled, the high-temperature stage refrigeration component and the low-temperature stage refrigeration component are activated simultaneously as a cascade system, so that the actual temperature and humidity of the chamber reach the set values. Since the low-temperature stage refrigeration component does not need to cool down from the high-temperature environment, it only needs to be responsible for the temperature control of the low-temperature cooling range, which greatly reduces the energy regulation ratio of the low-temperature stage refrigeration component, thereby reducing energy consumption. At the same time, the overall cooling capacity of the high and low temperature chamber is greatly reduced, and the operating power of the entire system is reduced due to the presence of the cascade system. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a segmented refrigeration system for a cryogenic high and low temperature chamber, provided as an embodiment of this application.

[0018] Figure 2 This is a schematic diagram of the structure of the low-temperature stage refrigeration component of a segmented refrigeration system for a cryogenic high and low temperature chamber, provided as an embodiment of this application.

[0019] Figure 3 This is a schematic diagram of the high-temperature stage refrigeration component of a segmented refrigeration system for cryogenic high and low temperature chambers, provided as an embodiment of this application.

[0020] Figure 4 This is a flowchart illustrating a control method for a segmented refrigeration system used in a cryogenic high and low temperature chamber, as provided in an embodiment of this application.

[0021] Figure label:

[0022] 100. Low-temperature stage refrigeration assembly; 101. Low-temperature stage evaporator; 101a. Inlet of the low-temperature stage evaporator;

[0023] 101b, outlet of the low-temperature stage evaporator; 102, low-temperature stage compressor; 102a, inlet of the low-temperature stage compressor;

[0024] 102b, outlet of the cryogenic stage compressor; 103, cryogenic stage oil separator; 103a, inlet of the cryogenic stage oil separator;

[0025] 103b, outlet of the cryogenic oil separator; 104, cryogenic water-cooled precooler;

[0026] 104a, Inlet of the low-temperature water-cooled precooler; 104b, Outlet of the low-temperature water-cooled precooler;

[0027] 105. Expansion tank; 105a. Inlet of expansion tank; 105b. Outlet of expansion tank;

[0028] 106, Low-temperature gas-liquid separator; 106a, Inlet of the low-temperature gas-liquid separator;

[0029] 106b, outlet of the cryogenic gas-liquid separator; 107, cryogenic high-pressure switch;

[0030] 108. Low-temperature exhaust temperature sensor; 109. Low-temperature hot gas bypass solenoid valve;

[0031] 110. Low-temperature hot gas bypass throttle valve; 111. Low-temperature dryer filter;

[0032] 112. Solenoid valve for low-temperature evaporator circuit; 113. Thermal expansion valve for low-temperature evaporator circuit;

[0033] 114. Low-temperature stage liquid injection circuit shut-off valve; 115. Low-temperature stage thermal opening liquid injection valve;

[0034] 116. Expansion tank inlet valve; 117. Expansion tank rear capillary tube; 118. Cryogenic stage low-pressure switch;

[0035] 119. Low-temperature high-pressure sensor;

[0036] 200. High-temperature refrigeration unit; 201. High-temperature evaporator; 201a. Inlet of high-temperature evaporator;

[0037] 201b, outlet of the high-temperature stage evaporator; 202, high-temperature stage compressor;

[0038] 202a, Inlet of the high-temperature stage compressor; 202b, Outlet of the high-temperature stage compressor;

[0039] 203, High-temperature oil separator; 203a, Inlet of high-temperature oil separator; 203b, Outlet of high-temperature oil separator;

[0040] 204, High-temperature water-cooled condenser; 204a, Inlet of high-temperature water-cooled condenser;

[0041] 204b, Outlet of high-temperature water-cooled condenser; 205, High-temperature liquid receiver;

[0042] 205a, Inlet of the high-temperature liquid receiver; 205b, Outlet of the high-temperature liquid receiver;

[0043] 206. Evaporator-condenser; 207. High-temperature gas-liquid separator;

[0044] 207a, Inlet of the high-temperature gas-liquid separator; 207b, Outlet of the high-temperature gas-liquid separator;

[0045] 208. High-temperature high-pressure switch; 209. High-temperature exhaust temperature sensor;

[0046] 210. High-temperature hot gas bypass solenoid valve; 211. High-temperature hot gas bypass throttle valve;

[0047] 212. Liquid storage tank shut-off valve; 213. High-temperature grade dryer filter; 214. High-temperature grade sight glass;

[0048] 215. High-temperature spray circuit shut-off valve; 216. High-temperature thermal opening spray valve;

[0049] 217. Evaporator-condenser solenoid valve; 218. Evaporator-condenser thermal expansion valve;

[0050] 219. High-temperature evaporator circuit solenoid valve; 220. High-temperature evaporator circuit electronic expansion valve;

[0051] 221. One-way valve for evaporator-condenser circuit; 222. High-temperature stage evaporator pressure regulating valve;

[0052] 223. High-temperature stage evaporator pressure bypass solenoid valve; 224. High-temperature stage evaporator circuit check valve;

[0053] 225. High-temperature low-pressure switch; 300. Cooling water assembly. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0055] This application provides a segmented refrigeration system and control method for cryogenic high and low temperature chambers. It should be noted that the segmented refrigeration system and control method provided in this application are applicable to any type of high and low temperature chamber.

[0056] like Figure 1 As shown, in one embodiment of this application, the segmented refrigeration system for cryogenic high and low temperature chambers includes a low-temperature stage refrigeration component 100 and a high-temperature stage refrigeration component 200.

[0057] The low-temperature refrigeration assembly 100 includes a low-temperature evaporator 101, a low-temperature compressor 102, a low-temperature oil separator 103, a low-temperature water-cooled precooler 104, an expansion tank 105, and a low-temperature gas-liquid separator 106. The outlet 102b of the low-temperature compressor 102 is connected to the inlet 103a of the low-temperature oil separator 103. The outlet 103b of the low-temperature oil separator 103 is connected to the inlet 104a of the low-temperature water-cooled precooler 104. The outlet 104b of the low-temperature water-cooled precooler 104 is connected to the inlet of the evaporator-condenser 206 and the expansion tank 106, respectively. The inlet 105a of the 5th stage gas-liquid separator is connected to the inlet 106a of the low-temperature stage gas-liquid separator 106. The outlet 106b of the low-temperature stage gas-liquid separator 106 is connected to the inlet 102a of the low-temperature stage compressor 102. The inlet 101a of the low-temperature stage evaporator 101 is connected to the outlet 206 of the evaporator-condenser. The inlet 106a of the low-temperature stage gas-liquid separator 106 is connected to the outlet 101b of the low-temperature stage evaporator 101, the outlet 105b of the expansion tank 105, the outlet of the evaporator-condenser 206, and the outlet 104b of the low-temperature stage water-cooled precooler 104.

[0058] The high-temperature stage refrigeration component 200 is interconnected with the low-temperature stage refrigeration component 100. The high-temperature stage refrigeration component 200 includes a high-temperature stage evaporator 201, a high-temperature stage compressor 202, a high-temperature stage oil separator 203, a high-temperature stage water-cooled condenser 204, a high-temperature stage liquid receiver 205, an evaporative condenser 206, and a high-temperature stage gas-liquid separator 207. The outlet 202b of the high-temperature stage compressor 202 is connected to the inlet 203a of the high-temperature stage oil separator 203. The outlet 203b of the high-temperature stage oil separator 203 is connected to the inlet 204a of the high-temperature stage water-cooled condenser 204. The outlet 204b of the high-temperature stage water-cooled condenser 204 is connected to the inlet 205a of the high-temperature stage liquid receiver 205. The outlet 205b of the high-temperature stage liquid receiver 205 is connected to the inlet of the evaporative condenser 206. The outlet 202b of compressor 202 is connected to the inlet 207a of high-temperature gas-liquid separator 207. The outlet 207b of high-temperature gas-liquid separator 207 is connected to the inlet 202a of high-temperature compressor 202. The inlet 207a of high-temperature gas-liquid separator 207 is connected to the outlet 206b of evaporator-condenser 206. The inlet 207a of high-temperature gas-liquid separator 207 is connected to the outlet 203b of high-temperature oil separator 203. The inlet 207a of high-temperature gas-liquid separator 207 is connected to the outlet 201b of high-temperature evaporator 201. The inlet 207a of high-temperature gas-liquid separator 207 is connected to the outlet 205b of high-temperature liquid receiver 205. The outlet 205b of high-temperature liquid receiver 205 is also connected to the inlet 201a of high-temperature evaporator 201.

[0059] Specifically, the expansion tank 105 is provided with an expansion tank inlet valve 116 at its inlet 105a and an expansion tank outlet capillary tube 117 at its outlet 105b.

[0060] In this embodiment, the temperature and humidity of the high-low temperature chamber are controlled by the high-temperature stage refrigeration component 200 in conjunction with the low-temperature stage refrigeration component 100. When only the temperature of the high-low temperature chamber is controlled, only the high-temperature stage refrigeration component 200 is activated, so that the actual temperature of the high-low temperature chamber reaches the set temperature. When the temperature and humidity of the high-low temperature chamber are controlled simultaneously, the high-temperature stage refrigeration component 200 and the low-temperature stage refrigeration component 100 are activated simultaneously as a cascade system, so that the actual temperature and humidity of the high-low temperature chamber reach the set values. Since the low-temperature stage refrigeration component 100 does not need to cool down from the high-temperature environment, it only needs to be responsible for the temperature control of the low-temperature cooling range, which greatly reduces the energy regulation ratio of the low-temperature stage refrigeration component 100, thereby reducing energy consumption. At the same time, the overall cooling capacity configuration of the high-low temperature chamber is greatly reduced, and the operating power of the entire system is reduced due to the existence of the cascade system.

[0061] like Figure 2 and Figure 3As shown, in one embodiment of this application, a low-temperature stage high-pressure switch 107 and a low-temperature stage exhaust temperature sensor 108 are provided between the outlet 102b of the low-temperature stage compressor 102 and the inlet 103a of the low-temperature stage oil separator 103, and a high-temperature stage high-pressure switch 208 and a high-temperature stage exhaust temperature sensor 209 are provided between the outlet 202b of the high-temperature stage compressor 202 and the inlet 203a of the high-temperature stage oil separator 203.

[0062] Specifically, a low-pressure switch 118 is also provided between the low-temperature compressor 102 and the low-temperature gas-liquid separator 106.

[0063] A first return pipe is also provided between the low-temperature oil separator 103 and the low-temperature compressor 102 to realize the movement of airflow from the low-temperature oil separator 103 to the low-temperature compressor 102. The connection point between the first return pipe and the low-temperature compressor 102 is located between the low-temperature low-pressure switch 118 and the low-temperature compressor 102.

[0064] A high-temperature low-pressure switch 225 is also provided between the high-temperature compressor 202 and the high-temperature gas-liquid separator 207.

[0065] A second return pipe is provided between the high-temperature oil separator 203 and the high-temperature compressor 202 to realize the movement of airflow from the high-temperature oil separator 203 to the high-temperature compressor 202. The connection point between the second return pipe and the high-temperature compressor 202 is located between the high-temperature low-pressure switch 225 and the high-temperature compressor 202.

[0066] In this embodiment, the high-temperature stage compressor 202 works in conjunction with the high-temperature stage oil separator 203 to achieve cooling above the temperature threshold, while the low-temperature stage compressor 102 works in conjunction with the low-temperature stage oil separator 103 and other components to achieve cooling below the temperature threshold.

[0067] For example, when the temperature threshold is -30°, the actual temperature of the high and low temperature chamber is -35°, but the set temperature of the high and low temperature chamber is -70°. In order to make the actual temperature inside the high and low temperature chamber reach the set temperature, it is necessary to simultaneously start the low temperature stage refrigeration component 100 and the high temperature stage refrigeration component 200 as a cascade system to improve the cooling efficiency.

[0068] If the actual temperature of the high and low temperature chamber is 10°C and the set temperature is -25°C, then in order to make the actual temperature inside the high and low temperature chamber reach the set temperature, it is only necessary to turn on the high temperature stage refrigeration component 200, thereby reducing the energy consumption of the high and low temperature chamber.

[0069] like Figure 2As shown, in one embodiment of this application, a low-temperature hot gas bypass solenoid valve 109 and a low-temperature hot gas bypass throttle valve 110 are sequentially arranged between the outlet 104b of the low-temperature water-cooled precooler 104 and the inlet 106a of the low-temperature gas-liquid separator 106. The inlet of the low-temperature hot gas bypass solenoid valve 109 is connected to the outlet 104b of the low-temperature water-cooled precooler 104, the outlet of the low-temperature hot gas bypass solenoid valve 109 is connected to the inlet of the low-temperature hot gas bypass throttle valve 110, and the outlet of the low-temperature hot gas bypass throttle valve 110 is connected to the inlet 106a of the low-temperature gas-liquid separator 106.

[0070] Specifically, the outlet 104b of the low-temperature water-cooled precooler 104 is also equipped with a low-temperature high-pressure sensor 119, which monitors the pressure at the outlet 104b of the low-temperature water-cooled precooler 104 in real time.

[0071] In this embodiment, cooling water enters the low-temperature water-cooled precooler 104 through the inlet of the cooling water system 300. The low-temperature water-cooled precooler 104 processes the cooling water. A portion of the processed cooling water passes sequentially through the low-temperature hot gas bypass solenoid valve 109 and the low-temperature hot gas bypass throttle valve 110, and finally reaches the low-temperature gas-liquid separator 106. Another portion of the processed cooling water passes sequentially through the evaporator condenser 206 and the low-temperature dryer filter 111. This portion of cooling water passing through the low-temperature dryer filter 111 is further divided into two sub-parts. One sub-part passes sequentially through the low-temperature evaporator solenoid valve 112 and the low-temperature evaporator thermal expansion valve 113 before entering the low-temperature evaporator 101. After processing in the low-temperature evaporator 101, it finally enters the low-temperature gas-liquid separator 106. The other sub-part of cooling water passes sequentially through the low-temperature spray shut-off valve 114 and the low-temperature thermal opening spray valve 115, and finally reaches the low-temperature gas-liquid separator.

[0072] like Figure 2 As shown, in one embodiment of this application, a low-temperature stage dryer filter 111 is provided at the outlet of the evaporator condenser 206. The inlet of the low-temperature stage dryer filter 111 is connected to the outlet of the evaporator condenser 206. A low-temperature stage evaporator solenoid valve 112 and a low-temperature stage evaporator thermal expansion valve 113 are provided between the outlet of the low-temperature stage dryer filter 111 and the inlet 101a of the low-temperature stage evaporator 101. A low-temperature stage liquid spray shut-off valve 114 and a low-temperature stage thermal opening liquid spray valve 115 are provided between the outlet of the low-temperature stage dryer filter 111 and the inlet 106a of the low-temperature stage gas-liquid separator 106.

[0073] In this embodiment, the condensate output from the evaporator condenser 206 is dried by the low-temperature drying filter 111, and the dried condensate is divided into two sub-parts, which enter the low-temperature vapor-liquid separator 106 through different routes.

[0074] like Figure 2 As shown, in one embodiment of this application, the outlet of the low-temperature stage dryer filter 111 is connected to the inlet of the low-temperature stage evaporator solenoid valve 112, the outlet of the low-temperature stage evaporator solenoid valve 112 is connected to the inlet of the low-temperature stage evaporator thermal expansion valve 113, the outlet of the low-temperature stage evaporator thermal expansion valve 113 is connected to the inlet 101a of the low-temperature stage evaporator 101, the outlet of the low-temperature stage dryer filter 111 is connected to the inlet of the low-temperature stage liquid spraying circuit shut-off valve 114, the outlet of the low-temperature stage liquid spraying circuit shut-off valve 114 is connected to the inlet of the low-temperature stage thermal opening liquid spray valve 115, and the outlet of the low-temperature stage thermal opening liquid spray valve 115 is connected to the inlet of the low-temperature stage gas-liquid separator 106.

[0075] In this embodiment, the condensate is divided into two sub-parts after passing through the low-temperature stage dryer filter 111. Before entering the low-temperature stage evaporator 101, the condensate of one sub-part passes through the low-temperature stage evaporator solenoid valve 112 and the low-temperature stage evaporator thermal expansion valve 113 in sequence. Both the low-temperature stage evaporator solenoid valve 112 and the low-temperature stage evaporator thermal expansion valve 113 can control whether the condensate passes through. Only when both the low-temperature stage evaporator solenoid valve 112 and the low-temperature stage evaporator thermal expansion valve 113 are in the open state can this sub-part of condensate enter the low-temperature stage evaporator 101.

[0076] like Figure 3 As shown, in one embodiment of this application, a high-temperature hot gas bypass solenoid valve 210 and a high-temperature hot gas bypass throttle valve 211 are provided between the outlet 203b of the high-temperature oil separator 203 and the inlet 207a of the high-temperature gas-liquid separator 207. The outlet 203b of the high-temperature oil separator 203 is connected to the inlet of the high-temperature hot gas bypass solenoid valve 210, the outlet of the high-temperature hot gas bypass solenoid valve 210 is connected to the inlet of the high-temperature hot gas bypass throttle valve 211, and the outlet of the high-temperature hot gas bypass throttle valve 211 is connected to the inlet 207a of the high-temperature gas-liquid separator 207.

[0077] In this embodiment, the condensate is divided into two parts after passing through the high-temperature oil separator 203. One part eventually enters the high-temperature gas-liquid separator 207, while the other part enters the high-temperature water-cooled condenser 204.

[0078] The liquid that ultimately enters the high-temperature gas-liquid separator 207 needs to pass through the high-temperature hot gas bypass solenoid valve 210 and the high-temperature hot gas bypass throttle valve 211 sequentially after exiting the high-temperature oil separator 203. The high-temperature hot gas bypass solenoid valve 210 and the high-temperature hot gas bypass throttle valve 211 control whether this part of the condensate can enter the high-temperature gas-liquid separator 207. Only when both the high-temperature hot gas bypass solenoid valve 210 and the high-temperature hot gas bypass throttle valve 211 are in the open state can the condensate directly enter the high-temperature gas-liquid separator 207 from the high-temperature oil separator 203.

[0079] like Figure 3 As shown, in one embodiment of this application, a storage tank shut-off valve 212, a high-temperature grade dryer filter 213, and a high-temperature grade sight glass 214 are sequentially arranged at the outlet 205b of the high-temperature grade liquid reservoir 205. The outlet 205b of the high-temperature grade liquid reservoir 205 is connected to the inlet of the storage tank shut-off valve 212, the outlet of the storage tank shut-off valve 212 is connected to the inlet of the high-temperature grade dryer filter 213, and the outlet of the high-temperature grade dryer filter 213 is connected to the inlet of the high-temperature grade sight glass 214. The high-temperature grade sight glass 214... A high-temperature stage liquid spray shut-off valve 215 and a high-temperature stage thermal opening liquid spray valve 216 are provided between the outlet of the high-temperature stage gas-liquid separator 207 and the inlet 207a of the high-temperature stage gas-liquid separator 207. An evaporator-condenser solenoid valve 217 and an evaporator-condenser thermal expansion valve 218 are provided between the outlet of the high-temperature stage sight glass 214 and the inlet of the evaporator-condenser 206. A high-temperature stage evaporator solenoid valve 219 and a high-temperature stage evaporator electronic expansion valve 220 are provided between the outlet of the high-temperature stage sight glass 214 and the inlet 201a of the high-temperature stage evaporator 201.

[0080] In this embodiment, the condensate is divided into three parts after passing through the high-temperature sight glass 214. The first part of the condensate passes through the high-temperature spray circuit shut-off valve 215 and the high-temperature thermal opening spray valve 216 in sequence before finally entering the high-temperature gas-liquid separator 207. The second part of the condensate passes through the evaporator-condenser circuit solenoid valve 217 and the evaporator-condenser circuit thermal expansion valve 218 before entering the evaporator-condenser 206. The last part of the condensate passes through the high-temperature evaporator circuit solenoid valve 219 and the high-temperature evaporator circuit electronic expansion valve 220 before entering the high-temperature evaporator 201.

[0081] like Figure 3As shown, in one embodiment of this application, the outlet of the high-temperature sight glass 214 is connected to the inlet of the high-temperature spray path shut-off valve 215; the outlet of the high-temperature spray path shut-off valve 215 is connected to the inlet of the high-temperature thermal opening spray valve 216; the outlet of the high-temperature thermal opening spray valve 216 is connected to the inlet 207a of the high-temperature gas-liquid separator 207; the outlet of the high-temperature sight glass 214 is connected to the inlet of the evaporator-condenser solenoid valve 217; the outlet of the evaporator-condenser solenoid valve 217 is connected to the inlet of the evaporator-condenser thermal expansion valve 218; the outlet of the evaporator-condenser thermal expansion valve 218 is connected to the inlet of the evaporator-condenser 206; the outlet of the high-temperature sight glass 214 is connected to the inlet of the high-temperature evaporator solenoid valve 219; and the outlet of the high-temperature evaporator solenoid valve 219 is connected to the high-temperature evaporator electronic expansion valve 219. The inlet of the expansion valve 220 is connected, and the outlet of the electronic expansion valve 220 of the high-temperature evaporator circuit is connected to the inlet 201a of the high-temperature evaporator 201. A high-temperature evaporator pressure regulating valve 222, a high-temperature evaporator pressure bypass solenoid valve 223, and a high-temperature evaporator circuit check valve 224 are provided between the outlet 201b of the high-temperature evaporator 201 and the inlet 207a of the high-temperature gas-liquid separator 207. The outlet 201b of the high-temperature evaporator 201 is connected to the inlet of the high-temperature evaporator pressure regulating valve 222. The outlet of the high-temperature evaporator pressure regulating valve 222 is connected to the inlet of the high-temperature evaporator pressure bypass solenoid valve 223. The outlet of the high-temperature evaporator pressure bypass solenoid valve 223 is connected to the inlet of the high-temperature evaporator circuit check valve 224. The outlet of the high-temperature evaporator circuit check valve 224 is connected to the inlet 207a of the high-temperature gas-liquid separator 207.

[0082] Specifically, an evaporator-condenser one-way valve 221 is provided between the evaporator-condenser 206 and the high-temperature gas-liquid separator 207, thereby controlling the output of the evaporator-condenser 206 to flow unidirectionally to the high-temperature gas-liquid separator 207.

[0083] In this embodiment, after the condensate enters the high-temperature evaporator 201, it is discharged from the high-temperature evaporator 201 and passes through the high-temperature evaporation pressure regulating valve 222, the high-temperature evaporation pressure bypass solenoid valve 223 and the high-temperature evaporator one-way valve 224 in sequence, and finally enters the high-temperature gas-liquid separator 207.

[0084] like Figure 2As shown in one embodiment of this application, the segmented refrigeration system for the cryogenic high and low temperature chamber further includes a cooling water assembly 300. The inlet of the cooling water assembly 300 is connected to the inlet 104a of the low-temperature water-cooled precooler 104 and the inlet 204a of the high-temperature water-cooled condenser 204, respectively. The outlet of the cooling water system 300 is connected to the outlet 104b of the low-temperature water-cooled precooler 104 and the outlet 204b of the high-temperature water-cooled condenser 204, respectively.

[0085] In this embodiment, the cooling water assembly 300 provides cooling water to the low-temperature water-cooled precooler 104 and the high-temperature water-cooled condenser 204 respectively, so as to maintain the normal operation of the low-temperature water-cooled precooler 104 and the high-temperature water-cooled condenser 204.

[0086] like Figure 4 As shown, in one embodiment of this application, a control method for a segmented refrigeration system for cryogenic high and low temperature chambers is provided, comprising:

[0087] S100 sets the temperature threshold for the high and low temperature chamber, defining the high-temperature stage cooling range and the low-temperature stage cooling range. All temperature values ​​within the high-temperature stage cooling range are greater than or equal to the temperature threshold, while all temperature values ​​within the low-temperature stage cooling range are less than the temperature threshold.

[0088] S200, set the required temperature for the high and low temperature chamber.

[0089] S300 determines whether the required temperature of the high and low temperature chamber is greater than or equal to the temperature threshold.

[0090] S400: If the required temperature of the high and low temperature chamber is greater than or equal to the temperature threshold, then the required temperature of the high and low temperature chamber is determined to be in the high temperature stage cooling range, and the high temperature stage refrigeration components are activated until the actual temperature of the high and low temperature chamber reaches the required temperature.

[0091] S500: If the required temperature of the high and low temperature chamber is less than the temperature threshold, it determines that the required temperature of the high and low temperature chamber is in the low temperature stage cooling range, and simultaneously starts the low temperature stage refrigeration component and the high temperature stage refrigeration component until the actual temperature of the high and low temperature chamber reaches the required temperature.

[0092] Optionally, the control method for the refrigeration system of the segmented refrigeration cryogenic high and low temperature chamber also includes:

[0093] K100 sets the temperature threshold for the high and low temperature chamber, defining the high-temperature stage cooling range and the low-temperature stage cooling range. All temperature values ​​within the high-temperature stage cooling range are greater than or equal to the temperature threshold, while all temperature values ​​within the low-temperature stage cooling range are less than the temperature threshold.

[0094] K200, set the required temperature and humidity for the high and low temperature chamber.

[0095] K300 determines whether the required temperature of the high and low temperature chamber is greater than or equal to the temperature threshold.

[0096] K400: If the required temperature of the high and low temperature chamber is greater than or equal to the temperature threshold, then the required temperature of the high and low temperature chamber is determined to be in the high temperature stage cooling range, and the high temperature stage refrigeration components are activated until the actual temperature of the high and low temperature chamber reaches 0℃.

[0097] K500 simultaneously activates both the low-temperature and high-temperature refrigeration components until the actual temperature of the high-low temperature chamber reaches the required temperature.

[0098] Specifically, this application mainly controls the humidity and temperature of the high and low temperature chamber, but there are two control modes: the first is to control only the temperature of the high and low temperature chamber, and the second is to control both the temperature and humidity of the high and low temperature chamber simultaneously.

[0099] When only the temperature of the high and low temperature chamber is controlled, if the set required temperature is below -30℃, it is necessary to simultaneously activate the high-temperature stage refrigeration component and the low-temperature stage refrigeration component, and operate the high-temperature stage refrigeration component and the low-temperature stage refrigeration component as a cascade system in order to achieve the required temperature.

[0100] Throughout the process, the actual temperature of the high and low temperature chamber is first determined. If the actual temperature of the high and low temperature chamber is greater than or equal to -30℃, then only the high-temperature stage refrigeration component is activated as the refrigeration system. When the actual temperature of the high and low temperature chamber is less than -30℃, the high-temperature stage evaporator solenoid valve 219 is closed, and the evaporator-condenser solenoid valve 217 is activated. After a delay, the low-temperature stage evaporator solenoid valve 112 is activated, so that the high-temperature stage refrigeration component acts as a cascade system, allowing the actual temperature of the high and low temperature chamber to reach the required temperature.

[0101] When the temperature and humidity of the high and low temperature chamber are controlled simultaneously, for example, when the temperature is between 15°C and 85°C and the humidity is between 20% and 100%, the temperature is usually higher than the ambient temperature within this range. Therefore, in most cases, heating is required instead of cooling. Only in certain special cases, such as when the temperature is 20°C and the humidity is 30%, are both the temperature and humidity lower than the ambient temperature and humidity. In this case, it is necessary to cool and dehumidify at the same time. In this case, only the high-temperature refrigeration unit 200 needs to be operated to achieve the functions of cooling and dehumidification at the same time.

[0102] However, if we want the actual temperature and humidity to reach the set values, we can only choose one of humidity or temperature to achieve this. Therefore, we select the high-temperature refrigeration component 200 for dehumidification control and use the high-temperature evaporation pressure regulating valve 222 to keep the evaporation temperature of the high-temperature evaporator 201 near 0°C so that the high-temperature evaporator 201 will not frost.

[0103] When the actual humidity reaches the set value but the actual temperature does not reach the set value, the solenoid valve 217 of the evaporator-condenser circuit and the solenoid valve 219 of the high-temperature evaporator circuit are opened simultaneously, so that the low-temperature evaporator 101 and the high-temperature evaporator 201 work at the same time. At this time, the low-temperature evaporator 101 mainly realizes the cooling function, and the high-temperature evaporator 201 mainly realizes the dehumidification function.

[0104] In this embodiment, the temperature threshold is set to divide the temperature range inside the high and low temperature chamber into two cooling zones. The temperature range that is higher than or equal to the temperature threshold is the high-temperature cooling zone, and the temperature range that is lower than the temperature threshold is the low-temperature cooling zone. This allows the cooling components to be activated accordingly in different cooling zones based on the set temperature, thereby achieving temperature control of the entire temperature range.

[0105] When the set temperature is within the high-temperature cooling range, only the high-temperature cooling component is activated. When the set temperature is within the low-temperature cooling range, both the high-temperature cooling component and the low-temperature cooling component are activated simultaneously.

[0106] The technical features of the above embodiments can be combined arbitrarily, and the execution order of the method steps is not restricted. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0107] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A segmented refrigeration system for cryogenic high and low temperature chambers, characterized in that, The segmented refrigeration system for the cryogenic high and low temperature chamber includes: A low-temperature stage refrigeration assembly includes a low-temperature stage evaporator, a low-temperature stage compressor, a low-temperature stage oil separator, a low-temperature stage water-cooled precooler, an expansion tank, and a low-temperature stage gas-liquid separator. The outlet of the low-temperature stage compressor is connected to the inlet of the low-temperature stage oil separator, the outlet of the low-temperature stage oil separator is connected to the inlet of the low-temperature stage water-cooled precooler, the outlet of the low-temperature stage water-cooled precooler is connected to the inlet of the evaporator-condenser, the inlet of the expansion tank, and the inlet of the low-temperature stage gas-liquid separator, respectively. The outlet of the low-temperature stage gas-liquid separator is connected to the inlet of the low-temperature stage compressor, the inlet of the low-temperature stage evaporator is connected to the outlet of the evaporator-condenser, and the inlet of the low-temperature stage gas-liquid separator is connected to the outlet of the low-temperature stage evaporator, the outlet of the expansion tank, the outlet of the evaporator-condenser, and the outlet of the low-temperature stage water-cooled precooler, respectively. A high-temperature stage refrigeration component is interconnected with the low-temperature stage refrigeration component. The high-temperature stage refrigeration component includes a high-temperature stage evaporator, a high-temperature stage compressor, a high-temperature stage oil separator, a high-temperature stage water-cooled condenser, a high-temperature stage liquid receiver, an evaporator-condenser, and a high-temperature stage gas-liquid separator. The outlet of the high-temperature stage compressor is connected to the inlet of the high-temperature stage oil separator. The outlet of the high-temperature stage oil separator is connected to the inlet of the high-temperature stage water-cooled condenser. The outlet of the high-temperature stage water-cooled condenser is connected to the inlet of the high-temperature stage liquid receiver. The outlet of the high-temperature stage liquid receiver is connected to the inlet of the evaporator-condenser. The outlet of the high-temperature stage compressor is connected to the inlet of the high-temperature stage gas-liquid separator. The outlet of the high-temperature stage gas-liquid separator is connected to the inlet of the high-temperature stage compressor. The inlet of the high-temperature stage gas-liquid separator is connected to the outlet of the evaporator-condenser. The inlet of the high-temperature stage gas-liquid separator is connected to the outlet of the high-temperature stage oil separator. The inlet of the high-temperature stage gas-liquid separator is connected to the outlet of the high-temperature stage evaporator. The inlet of the high-temperature stage gas-liquid separator is connected to the outlet of the high-temperature stage liquid receiver. The outlet of the high-temperature stage liquid receiver is also connected to the inlet of the high-temperature stage evaporator. When the required temperature of the high and low temperature chamber is in the high-temperature stage cooling range, only the high-temperature stage refrigeration component is activated to bring the actual temperature of the high and low temperature chamber to the required temperature. When the required temperature of the high and low temperature chamber is in the low-temperature stage cooling range, both the high-temperature stage refrigeration component and the low-temperature stage refrigeration component are activated to bring the actual temperature of the high and low temperature chamber to the required temperature.

2. The segmented refrigeration system for cryogenic high and low temperature chambers according to claim 1, characterized in that, A low-temperature stage high-pressure switch and a low-temperature stage exhaust temperature sensor are installed between the outlet of the low-temperature stage compressor and the inlet of the low-temperature stage oil separator. A high-temperature stage high-pressure switch and a high-temperature stage exhaust temperature sensor are also installed between the outlet of the high-temperature stage compressor and the inlet of the high-temperature stage oil separator.

3. The segmented refrigeration system for cryogenic high and low temperature chambers according to claim 2, characterized in that, A low-temperature stage hot gas bypass solenoid valve and a low-temperature stage hot gas bypass throttling valve are sequentially installed between the outlet of the low-temperature stage water-cooled precooler and the inlet of the low-temperature stage gas-liquid separator. The inlet of the low-temperature stage hot gas bypass solenoid valve is connected to the outlet of the low-temperature stage water-cooled precooler, the outlet of the low-temperature stage hot gas bypass solenoid valve is connected to the inlet of the low-temperature stage hot gas bypass throttling valve, and the outlet of the low-temperature stage hot gas bypass throttling valve is connected to the inlet of the low-temperature stage gas-liquid separator.

4. The segmented refrigeration system for cryogenic high and low temperature chambers according to claim 3, characterized in that, A low-temperature stage dryer filter is installed at the outlet of the evaporator-condenser. The inlet of the low-temperature stage dryer filter is connected to the outlet of the evaporator-condenser. A low-temperature stage evaporator solenoid valve and a low-temperature stage evaporator thermal expansion valve are installed between the outlet of the low-temperature stage dryer filter and the inlet of the low-temperature stage evaporator. A low-temperature stage liquid spray shut-off valve and a low-temperature stage thermal opening liquid spray valve are installed between the outlet of the low-temperature stage dryer filter and the inlet of the low-temperature stage gas-liquid separator.

5. The segmented refrigeration system for cryogenic high and low temperature chambers according to claim 4, characterized in that, The outlet of the low-temperature stage dryer filter is connected to the inlet of the low-temperature stage evaporator solenoid valve. The outlet of the low-temperature stage evaporator solenoid valve is connected to the inlet of the low-temperature stage evaporator thermal expansion valve. The outlet of the low-temperature stage evaporator thermal expansion valve is connected to the inlet of the low-temperature stage evaporator. The outlet of the low-temperature stage dryer filter is connected to the inlet of the low-temperature stage liquid spray shut-off valve. The outlet of the low-temperature stage liquid spray shut-off valve is connected to the inlet of the low-temperature stage thermal opening liquid spray valve. The outlet of the low-temperature stage thermal opening liquid spray valve is connected to the inlet of the low-temperature stage gas-liquid separator.

6. The segmented refrigeration system for cryogenic high and low temperature chambers according to claim 5, characterized in that, A high-temperature hot gas bypass solenoid valve and a high-temperature hot gas bypass throttle valve are installed between the outlet of the high-temperature oil separator and the inlet of the high-temperature gas-liquid separator. The outlet of the high-temperature oil separator is connected to the inlet of the high-temperature hot gas bypass solenoid valve, the outlet of the high-temperature hot gas bypass solenoid valve is connected to the inlet of the high-temperature hot gas bypass throttle valve, and the outlet of the high-temperature hot gas bypass throttle valve is connected to the inlet of the high-temperature gas-liquid separator.

7. The segmented refrigeration system for cryogenic high and low temperature chambers according to claim 6, characterized in that, The outlet of the high-temperature liquid receiver is sequentially equipped with a liquid receiver shut-off valve, a high-temperature dryer filter, and a high-temperature sight glass. The outlet of the high-temperature liquid receiver is connected to the inlet of the liquid receiver shut-off valve. The outlet of the liquid receiver shut-off valve is connected to the inlet of the high-temperature dryer filter. The outlet of the high-temperature dryer filter is connected to the high-temperature sight glass. A high-temperature liquid spray shut-off valve and a high-temperature thermal opening liquid spray valve are installed between the outlet of the high-temperature sight glass and the inlet of the high-temperature gas-liquid separator. An evaporator-condenser solenoid valve and an evaporator-condenser thermal expansion valve are installed between the outlet of the high-temperature sight glass and the inlet of the high-temperature evaporator. A high-temperature evaporator-evaporator solenoid valve and a high-temperature evaporator-evaporator electronic expansion valve are installed between the outlet of the high-temperature sight glass and the inlet of the high-temperature evaporator.

8. The segmented refrigeration system for cryogenic high and low temperature chambers according to claim 7, characterized in that, The outlet of the high-temperature stage sight glass is connected to the inlet of the high-temperature stage spray circuit shut-off valve. The outlet of the high-temperature stage spray circuit shut-off valve is connected to the inlet of the high-temperature stage thermal opening spray valve. The outlet of the high-temperature stage thermal opening spray valve is connected to the inlet of the high-temperature stage gas-liquid separator. The outlet of the high-temperature stage sight glass is connected to the inlet of the evaporator-condenser circuit solenoid valve. The outlet of the evaporator-condenser circuit solenoid valve is connected to the inlet of the evaporator-condenser circuit thermal expansion valve. The outlet of the evaporator-condenser circuit thermal expansion valve is connected to the inlet of the evaporator-condenser. The outlet of the high-temperature stage sight glass is connected to the inlet of the high-temperature stage evaporator circuit solenoid valve. The outlet of the high-temperature stage evaporator circuit solenoid valve is connected to the inlet of the high-temperature stage evaporator circuit solenoid valve. The inlet of the expansion valve is connected, the outlet of the electronic expansion valve of the high-temperature evaporator is connected to the inlet of the high-temperature evaporator, and a high-temperature evaporator pressure regulating valve, a high-temperature evaporator pressure bypass solenoid valve, and a high-temperature evaporator one-way valve are provided between the outlet of the high-temperature evaporator and the inlet of the high-temperature gas-liquid separator. The outlet of the high-temperature evaporator is connected to the inlet of the high-temperature evaporator pressure regulating valve, the outlet of the high-temperature evaporator pressure regulating valve is connected to the inlet of the high-temperature evaporator pressure bypass solenoid valve, the outlet of the high-temperature evaporator pressure bypass solenoid valve is connected to the inlet of the high-temperature evaporator one-way valve, and the outlet of the high-temperature evaporator one-way valve is connected to the inlet of the high-temperature gas-liquid separator.

9. The segmented refrigeration system for cryogenic high and low temperature chambers according to claim 1, characterized in that, The segmented refrigeration system for cryogenic high and low temperature chambers also includes: The cooling water assembly has its inlet connected to the inlet of the low-temperature water-cooled precooler and the inlet of the high-temperature water-cooled condenser, respectively, and its outlet connected to the outlet of the low-temperature water-cooled precooler and the outlet of the high-temperature water-cooled condenser, respectively.

10. A control method for a segmented refrigeration system for a cryogenic high and low temperature chamber, characterized in that, The control method for the refrigeration system of the segmented refrigeration cryogenic high and low temperature chamber includes: Set the temperature threshold of the high and low temperature chamber, and define the high temperature stage cooling range and the low temperature stage cooling range; all temperature values ​​in the high temperature stage cooling range are greater than or equal to the temperature threshold, and all temperature values ​​in the low temperature stage cooling range are less than the temperature threshold. Set the required temperature for the high and low temperature chamber; Determine whether the required temperature of the high and low temperature chamber is greater than or equal to the temperature threshold. If the required temperature of the high and low temperature chamber is greater than or equal to the temperature threshold, then the required temperature of the high and low temperature chamber is determined to be in the high temperature stage cooling range, and the high temperature stage refrigeration components are started until the actual temperature of the high and low temperature chamber reaches the required temperature. If the required temperature of the high and low temperature chamber is less than the temperature threshold, then the required temperature of the high and low temperature chamber is determined to be in the low temperature stage cooling range. At the same time, the low temperature stage refrigeration components and the high temperature stage refrigeration components are started until the actual temperature of the high and low temperature chamber reaches the required temperature.

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