Refrigerating system and control method of high and low temperature environmental test chamber adopting cold storage supercooler

Abstract

The application discloses a refrigerating system and control method of a high-low temperature environment test box adopting a cold storage supercooler, and the system comprises a compressor, a condenser, a cold storage supercooler, a regenerator, an evaporator, an electromagnetic valve and a capillary tube. When the high-low temperature environment test system is maintained in a constant temperature operation mode, the refrigerating load needs to be adjusted. The traditional method of bypassing cold quantity can achieve the purpose of adjusting the cold quantity and controlling the temperature, but will cause waste of surplus cold quantity and increase of energy consumption. The application provides a novel energy-saving refrigerating system, wherein when the system is in a low-load constant temperature operation mode, part of high-pressure refrigerant at the outlet of the regenerator enters the cold storage supercooler after passing through a bypass valve and a capillary throttling device, so that the surplus cold quantity is stored in the cold storage supercooler, and the power consumption required for temperature control in the heat balance mode is reduced. When the unit completes the constant temperature operation and enters a temperature reduction operation mode, the refrigerant at the outlet of the condenser enters the regenerator after passing through the cold storage supercooler, so that the condensation and supercooling of the low-boiling point working medium are accelerated, and thus the temperature reduction speed of the system is improved and the energy consumption of the system is reduced.

Description

Technical Field

[0001] This invention belongs to the technical field of high and low temperature test chambers, specifically relating to a refrigeration system and control method for a high and low temperature environment test chamber using a cold storage subcooler. Background Technology

[0002] In recent years, industrialization has progressed rapidly, and information technology development has continuously improved, leading to increasingly higher requirements for product performance, safety, and reliability. The performance and reliability of military, automotive, aerospace, and electronic products are closely related to the ambient temperature, necessitating relevant environmental adaptability tests before formal use. High and low temperature environmental test chambers can simulate rapid and wide-range temperature changes and are widely used equipment.

[0003] Traditional high and low temperature test chambers requiring temperature control below -70℃ generally employ cascade refrigeration or two-stage compression refrigeration technologies, using two compressors to meet the requirements for cooling speed and depth. However, this approach suffers from high equipment costs and high energy consumption. Hybrid refrigerant cryogenic refrigeration technology can achieve temperatures below -70℃ using a single compressor, offering advantages such as rapid cooling, low equipment cost, and simple system structure. However, in traditional refrigeration technologies, when the equipment is operating at a constant temperature, electric heating balancing technology is commonly used to balance the heat and cold within the chamber, thus increasing system power consumption. Especially during high-temperature operation, when the chamber temperature exceeds the ambient temperature, the refrigeration system must still be activated to provide cooling to prevent further temperature increases due to heat leakage from the fan and chamber, as well as heat generation from the tested components. Moreover, at this time, the compressor flow rate is high, resulting in high compressor power consumption and a large cooling capacity. Therefore, the electrical heating load required for temperature control also increases, undoubtedly leading to energy waste. Therefore, reducing the output of cooling capacity in the chamber and storing the excess cooling capacity for low-temperature refrigeration has become a new energy-saving technology direction for high and low temperature environmental test chamber refrigeration systems. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of the above-mentioned technologies by combining a cold storage subcooler with a mixed working fluid low-temperature technology, and to propose a refrigeration system and control method for a high and low temperature environment test chamber that uses a cold storage subcooler.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A refrigeration system for a high and low temperature environmental test chamber employing a cold storage subcooler includes a compressor 101, an oil separator 102, a condenser 103, a three-way valve 104, a regenerator 105, a throttling capillary tube I 106, a solenoid valve I 107, a throttling capillary tube II 108, an evaporator 109, a solenoid valve II 110, a throttling capillary tube III 111, a cold storage subcooler 112, an expansion container 113, a solenoid valve III 114, and a solenoid valve IV 115; wherein, the outlet of the compressor 101 is connected to... Oil separator 102 and condenser 103 are connected in sequence. The outlet of condenser 103 is split into two branches, connected to the inlet 1041 of three-way valve 104 and the inlet of solenoid valve IV 115, respectively. The second outlet 1043 of three-way valve 104 is connected to the high-pressure side channel inlet of cold storage subcooler 112. The first outlet 1042 of three-way valve 104 is connected to the high-pressure side channel outlet of cold storage subcooler 112 and the high-pressure side channel inlet of regenerator 105. The high-pressure side channel outlet of regenerator 105 is split into two branches. The three channels are respectively connected to the inlets of throttling capillary tube I 106, solenoid valve I 107, and solenoid valve II 110. The outlet of throttling capillary tube I 106 is connected to the inlet of evaporator 109; the outlet of solenoid valve I 107 is connected to the inlet of throttling capillary tube II 108; the outlet of throttling capillary tube II 108 is connected to the inlet of evaporator 109; the outlet of evaporator 109 is connected to the inlet of the low-pressure side channel of regenerator 105; the outlet of the low-pressure side channel of regenerator 105 is connected to the inlet of compressor 101 and solenoid valve II 110. The outlet of valve III 114 is connected; the outlet of solenoid valve II 110 is connected to the inlet of throttling capillary tube III 111, the outlet of throttling capillary tube III 111 is connected to the inlet of the low-pressure side flow channel of the cold storage subcooler 112, the outlet of the low-pressure side flow channel of the cold storage subcooler 112 is connected to the outlet of oil separator 102, the outlet of solenoid valve III 114 and the inlet of compressor 101; the inlet and outlet of expansion container 113 are respectively connected to the outlet of solenoid valve IV 115 and the inlet of solenoid valve III 114; thus forming a complete circulation system.

[0007] Using expansion container 113 to store excess refrigerant effectively regulates the pressure of the refrigeration system, ensuring that the high and low pressures of the compressor are within the design range. The advantage of placing expansion container 113 on the outlet side of condenser 103 is that, compared to placing it on the discharge side of compressor, placing it on the outlet side of condenser 103 allows for faster storage of refrigerant and a faster reduction in compressor discharge pressure, ensuring the safe operation of compressor 101.

[0008] The aforementioned control method for a refrigeration system employing a cold storage subcooler in a high and low temperature environmental test chamber. This refrigeration system utilizes a cold storage subcooler 112. In constant temperature operation mode, the temperature of the high and low temperature environmental test chamber is T1. When the temperature of the chamber needs to be lowered from T1 to T2, the system switches from constant temperature operation mode to rapid cooling mode. When the temperature of the cold storage subcooler 112 is lower than the outlet temperature of the condenser 103, solenoid valve I 107 opens, solenoid valve II 110 closes, the first outlet 1042 of the three-way valve 104 closes, and the inlet 1041 and second outlet 1043 of the three-way valve 104 open. The refrigerant from the condenser 103 is first subcooled by the cold storage subcooler 112 before entering the regenerator 105. When the temperature of the cold storage subcooler 112 is higher than the outlet temperature of the condenser 103, the system switches from constant temperature operation mode to rapid cooling mode. When the condenser 103 outlet temperature reaches a certain level, solenoid valve I 107 is open, solenoid valve II 110 is closed, the inlet 1041 and first outlet 1042 of three-way valve 104 are open, and the second outlet 1043 of three-way valve 104 is closed. The refrigerant bypasses the cold storage subcooler 112 and enters the regenerator 105 for heat exchange. When the temperature of the high and low temperature environment test chamber reaches temperature T2, the electric heating of the high and low temperature environment test chamber is turned on to balance the excess cooling capacity of evaporator 109 and maintain the temperature stability of the high and low temperature environment test chamber. Solenoid valve I 107 is closed, and only the throttling capillary tube I 106 is used for throttling to reduce the excess cooling capacity of evaporator 109 and reduce the electric heating power. When the change in electric heating power is less than 5%, the refrigeration system is considered to have reached a stable operating state, and at this time, it switches to constant temperature cold storage mode.

[0009] When the system switches to constant temperature cold storage mode, the electric heating power is reduced to prevent the temperature of the high and low temperature environmental test chamber from rising due to the lag in the control process after the cold energy bypass is due to the heating amount being higher than the cold energy. Solenoid valve II 110 is opened, the inlet 1041 to the first outlet 1042 of the three-way valve 104 is opened, and the second outlet 1043 of the three-way valve 104 is closed. The refrigerant from the condenser 103 is directly reheated through the regenerator 105. After some of the refrigerant passes through the throttling capillary tube III 111, the excess cold energy is stored in the cold storage subcooler 112, reducing the electric power required for temperature control of the high and low temperature environmental test chamber. When the cold storage subcooler 112 is full of cold energy, solenoid valve II 110 is closed, and the constant temperature cold storage process ends.

[0010] When the refrigeration system needs to switch back to rapid cooling mode, solenoid valve I 107 opens, solenoid valve II 110 closes, the inlet 1041 to the second outlet 1043 channel of three-way valve 104 opens, and the first outlet 1042 closes. The refrigerant from condenser 103 is first subcooled by the cold storage subcooler 112 before entering the regenerator 105. This utilizes the cooling capacity of the cold storage subcooler 112 from the previous constant-temperature cold storage mode to accelerate the establishment of reheat in the refrigeration system during this rapid cooling process, reducing the evaporation temperature and achieving the goal of accelerating the cooling speed and reducing compressor power consumption. Compared with the prior art, the present invention has the following advantages:

[0011] 1. Traditional high and low temperature environmental test chambers requiring temperature control below -70℃ generally employ cascade refrigeration or two-stage compression refrigeration technologies. However, these technologies suffer from high equipment costs and high energy consumption. The mixed-works-refrigerant cryogenic refrigeration technology of this invention can achieve cryogenic refrigeration below -70℃ using a single compressor, featuring rapid cooling, low equipment cost, and a simple system structure.

[0012] 2. Traditional high and low temperature environmental test chambers generally use electric heating balancing technology to achieve thermal equilibrium within the chamber and maintain constant temperature control. This undoubtedly results in a waste of cooling capacity and electrical energy. The system of this invention, however, employs a cold storage subcooler to store excess cooling capacity generated during the constant temperature process. This not only reduces the energy consumption of the refrigeration system but also accelerates the cooling speed in the system's rapid cooling mode, thereby improving the performance of the high and low temperature environmental test chamber. Attached Figure Description

[0013] Figure 1 A refrigeration system employing a cold storage subcooler for a high and low temperature environmental test chamber.

[0014] A diagram illustrating the cycle. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of this invention clearer and more concise, the invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0016] Implementation Cases

[0017] like Figure 1As shown, the present invention discloses a refrigeration system for a high and low temperature environmental test chamber using a cold storage subcooler, comprising a compressor 101, an oil separator 102, a condenser 103, a three-way valve 104, a regenerator 105, a throttling capillary tube I 106, a solenoid valve I 107, a throttling capillary tube II 108, an evaporator 109, a solenoid valve II 110, a throttling capillary tube III 111, a cold storage subcooler 112, an expansion container 113, a solenoid valve III 114, and a solenoid valve IV 115; wherein, the compressor 101... The outlet 01 is sequentially connected to the oil separator 102 and the condenser 103. The outlet of the condenser 103 is split into two branches, which are connected to the inlet 1041 of the three-way valve 104 and the inlet of the solenoid valve Ⅳ 115, respectively. The second outlet 1043 of the three-way valve 104 is connected to the high-pressure side channel inlet of the cold storage subcooler 112. The first outlet 1042 of the three-way valve 104 is connected to the high-pressure side channel outlet of the cold storage subcooler 112 and the high-pressure side channel inlet of the regenerator 105. The high-pressure side channel of the regenerator 105... The outlet is divided into three paths, connected to the inlet of throttling capillary tube I 106, solenoid valve I 107, and solenoid valve II 110 respectively. The outlet of throttling capillary tube I 106 is connected to the inlet of evaporator 109; the outlet of solenoid valve I 107 is connected to the inlet of throttling capillary tube II 108; the outlet of throttling capillary tube II 108 is connected to the inlet of evaporator 109; the outlet of evaporator 109 is connected to the low-pressure side channel inlet of regenerator 105; and the low-pressure side channel outlet of regenerator 105 is connected to the inlet of compressor 101 and... The outlet of solenoid valve III 114 is connected; the outlet of solenoid valve II 110 is connected to the inlet of throttling capillary tube III 111, the outlet of throttling capillary tube III 111 is connected to the inlet of the low-pressure side flow channel of the cold storage subcooler 112, the outlet of the low-pressure side flow channel of the cold storage subcooler 112 is connected to the outlet of oil separator 102, the outlet of solenoid valve III 114 and the inlet of compressor 101; the inlet and outlet of expansion container 113 are connected to the outlet of solenoid valve IV 115 and the inlet of solenoid valve III 114 respectively, forming a complete circulation system.

[0018] The aforementioned control method for a refrigeration system employing a cold storage subcooler in a high and low temperature environmental test chamber. This refrigeration system utilizes a cold storage subcooler 112. In constant temperature operation mode, for example, if the temperature of the high and low temperature environmental test chamber is -40℃ and the temperature of the cold storage subcooler 112 is lower than the outlet temperature of the condenser 103, when the temperature of the high and low temperature environmental test chamber needs to be reduced from -40℃ to -80℃, the system switches from constant temperature operation mode to rapid cooling mode. At this time, solenoid valve I 107 opens, solenoid valve II 110 closes, the first outlet 1042 of the three-way valve 104 closes, and the inlet 1041 and second outlet 1043 of the three-way valve 104 open. The refrigerant from the condenser 103 is first subcooled by the cold storage subcooler 112. Then, it enters the regenerator 105. This control method can use the cold energy stored in the cold storage subcooler 112 to reduce the temperature of the high-pressure side inlet of the regenerator 106, thereby reducing the evaporation temperature and accelerating the cooling rate. When the temperature of the cold storage subcooler 112 is higher than the outlet temperature of the condenser 103, the cold storage subcooler 112 is a heat load for the system. The refrigerant will lose some cold energy when exchanging heat with the cold storage subcooler 112, thus reducing the cooling rate. Therefore, at this time, the solenoid valve I 107 is open, the solenoid valve II 110 is closed, the inlet 1041 and the first outlet 1042 of the three-way valve 104 are open, and the second outlet 1043 of the three-way valve 104 is closed. The refrigerant bypasses the cold storage subcooler 112 and enters the regenerator 105 for heat exchange.

[0019] When the temperature of the high and low temperature environment test chamber reaches -80℃, the electric heating of the high and low temperature environment test chamber is turned on to balance the excess cooling capacity of the evaporator 109 and maintain the temperature stability of the high and low temperature environment test chamber. The solenoid valve I107 is closed, and only the throttling capillary tube I106 is used for throttling. This can reduce the circulation flow of the entire system and thus reduce the excess cooling capacity of the evaporator 109, and reduce the electric heating power. When the change in electric heating power is less than 5%, it is considered that the refrigeration system has reached a stable operating state, and at this time, it switches to constant temperature cold storage mode.

[0020] When the system switches to constant temperature cold storage mode, the electric heating power is reduced to prevent the temperature of the high and low temperature environmental test chamber from rising due to the lag in the control process after the cold energy bypass is due to the heating amount being higher than the cold energy. Solenoid valve II 110 is opened, the inlet 1041 to the first outlet 1042 of the three-way valve 104 is opened, and the second outlet 1043 of the three-way valve 104 is closed. The refrigerant from the condenser 103 is directly reheated through the regenerator 105. After some of the refrigerant passes through the throttling capillary tube III 111, the excess cold energy is stored in the cold storage subcooler 112, reducing the electric power required for temperature control of the high and low temperature environmental test chamber. When the cold storage subcooler 112 is full of cold energy, solenoid valve II 110 is closed, and the constant temperature cold storage process ends.

[0021] When the refrigeration system needs to switch back to rapid cooling mode, solenoid valve I 107 opens, solenoid valve II 110 closes, the inlet 1041 to the second outlet 1043 channel of the three-way valve 104 opens, and the first outlet 1042 closes. The refrigerant from the condenser 103 is first subcooled by the cold storage subcooler 112 before entering the regenerator 105. This utilizes the cooling capacity of the cold storage subcooler 112 from the previous constant temperature cold storage mode to accelerate the establishment of reheat in the refrigeration system during this rapid cooling process, reduce the evaporation temperature, and achieve the purpose of accelerating the cooling speed and reducing the power consumption of the compressor.

Claims

1. A refrigeration system for a high and low temperature environmental test chamber using a cold storage subcooler, characterized in that: The system includes a compressor (101), an oil separator (102), a condenser (103), a three-way valve (104), a regenerator (105), a throttling capillary tube I (106), a solenoid valve I (107), a throttling capillary tube II (108), an evaporator (109), a solenoid valve II (110), a throttling capillary tube III (111), a cold storage subcooler (112), an expansion vessel (113), a solenoid valve III (114), and a solenoid valve IV (115); wherein, the outlet of the compressor (101) is connected to the oil separator (102) and the condenser. (103) are connected in sequence. The outlet of the condenser (103) is split into two paths and connected to the inlet (1041) of the three-way valve (104) and the inlet of the solenoid valve IV (115) respectively. The second outlet (1043) of the three-way valve (104) is connected to the high-pressure side channel inlet of the cold storage subcooler (112). The first outlet (1042) of the three-way valve (104) is connected to the high-pressure side channel outlet of the cold storage subcooler (112) and the high-pressure side channel inlet of the regenerator (105). The high-pressure side channel outlet of the regenerator (105) is split into three paths and connected to the throttling capillary tube respectively. The inlets of solenoid valves I (106), I (107), and II (110) are connected; the outlet of capillary tube I (106) is connected to the inlet of evaporator (109); the outlet of solenoid valve I (107) is connected to the inlet of capillary tube II (108); the outlet of capillary tube II (108) is connected to the inlet of evaporator (109); the outlet of evaporator (109) is connected to the inlet of the low-pressure side channel of regenerator (105); the outlet of the low-pressure side channel of regenerator (105) is connected to the inlet of compressor (101) and the outlet of solenoid valve III (114). Connected; the outlet of solenoid valve II (110) is connected to the inlet of throttling capillary tube III (111), the outlet of throttling capillary tube III (111) is connected to the inlet of the low-pressure side flow channel of the cold storage subcooler (112), the outlet of the low-pressure side flow channel of the cold storage subcooler (112) is connected to the outlet of oil separator (102), the outlet of solenoid valve III (114), and the inlet of compressor (101); the inlet of expansion container (113) is connected to the outlet of solenoid valve IV (115), and the outlet of expansion container (113) is connected to the inlet of solenoid valve III (114); forming a complete circulation system.

2. The refrigeration system of a high and low temperature environment test chamber using a cold storage subcooler according to claim 1, characterized in that: The expansion container (113) stores excess refrigerant and regulates the pressure of the refrigeration system.

3. The control method for the refrigeration system of a high and low temperature environmental test chamber using a cold storage subcooler as described in claim 1 or 2, characterized in that: The refrigeration system uses a cold storage subcooler (112). In constant temperature operation mode, the temperature of the high and low temperature environmental test chamber is T1. When the temperature of the high and low temperature environmental test chamber needs to be reduced from T1 to T2, the system switches from constant temperature operation mode to rapid cooling mode. When the temperature of the cold storage subcooler (112) is lower than the outlet temperature of the condenser (103), solenoid valve I (107) opens, solenoid valve II (110) closes, the first outlet (1042) of the three-way valve (104) closes, and the inlet (1041) and second outlet (1043) channels of the three-way valve (104) open. The refrigerant from the condenser (103) is first subcooled by the cold storage subcooler (112) before entering the regenerator (105). When the temperature of the cold storage subcooler (112) is higher than the outlet temperature of the condenser (103), the refrigerant... Solenoid valve I (107) is open, solenoid valve II (110) is closed, the inlet (1041) and first outlet (1042) of the three-way valve (104) are open, and the second outlet (1043) of the three-way valve (104) is closed. The refrigerant bypasses the cold storage subcooler (112) and enters the regenerator (105) for heat exchange. When the temperature of the high and low temperature environment test chamber reaches temperature T2, the electric heating of the high and low temperature environment test chamber is turned on to balance the excess cold energy of the evaporator (109) and maintain the stability of the temperature of the high and low temperature environment test chamber. Solenoid valve I (107) is closed, and only the throttling capillary tube I (106) is used for throttling to reduce the excess cold energy of the evaporator (109) and reduce the electric heating power. When the change in the electric heating power is less than 5%, it is considered that the refrigeration system has reached a stable operating state. At this time, it is switched to constant temperature cold storage mode. When the system switches to constant temperature cold storage mode, the electric heating power is reduced to prevent the temperature of the high and low temperature environment test chamber from rising due to the lag in the control process after the cold bypass is caused by the heating amount being higher than the cold amount. Solenoid valve II (110) is opened, the inlet (1041) to the first outlet (1042) of the three-way valve (104) is opened, and the second outlet (1043) of the three-way valve (104) is closed. The refrigerant from the condenser (103) is directly reheated through the regenerator (105). After some of the refrigerant passes through the throttling capillary tube III (111), the excess cold energy is stored in the cold storage subcooler (112), reducing the electric power required for temperature control of the high and low temperature environment test chamber. When the cold storage subcooler (112) is full, solenoid valve II (110) is closed, and the constant temperature cold storage process ends. When the refrigeration system needs to switch to rapid cooling mode again, solenoid valve I (107) opens, solenoid valve II (110) closes, the inlet (1041) to the second outlet (1043) channel of the three-way valve (104) opens, and the first outlet (1042) closes. The refrigerant from the condenser (103) is first subcooled by the cold storage subcooler (112) and then enters the regenerator (105). In this way, the cold energy of the cold storage subcooler (112) in the previous constant temperature cold storage mode can be used to accelerate the establishment of the refrigeration system regeneration in this rapid cooling process, reduce the evaporation temperature, and achieve the purpose of accelerating the cooling speed and reducing the power consumption of the compressor.

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