Energy storage liquid cooling unit with precooling system

Abstract

The utility model discloses an energy storage liquid cooling unit with a precooling system, which relates to the technical field of liquid cooling hosts and comprises a unit shell, an electric control unit is arranged in the unit shell and connected with a refrigeration module, the refrigeration module is provided with a refrigerator, the refrigerator is provided with a refrigerator frame, and the precooling system is connected with the refrigerator frame. A precooler and a condenser which are attached to each other are arranged in the refrigerator frame, and the width of a fin of the refrigerator is the sum of the width of the fin of the precooler and the width of the fin of the condenser. The precooler and the condenser adopt the same fin type structural design, the heat exchange area of the precooler and the condenser can be increased when the precooler and the condenser are independently used, and the condensing pressure of the refrigerating system can be further reduced under the high-temperature working condition and the precooling condition.

Description

Technical Field

[0001] The utility model relates to the technical field of liquid cooling mainframes, in particular to an energy storage liquid cooling unit with a precooling system. Background Art

[0002] The application operating temperature range of the energy storage liquid cooling host is -30~55℃. As the heart of the liquid cooling system, the liquid cooling host must always maintain a safe and stable working state. In harsh application environments, such as when operating at the two extreme ranges of -30℃ and 55℃, the liquid cooling host may have various system failures and unstable system operation during operation.

[0003] For example, Chinese patent CN212647364U, published on March 2, 2021, includes a computer host housing, a metal cooling box is installed on one side of the center of the computer host housing, a computer motherboard is installed in the center of the metal cooling box, a sealing cover is fixedly connected to the top of the metal cooling box, a data connection line is fixedly connected to the top of the computer motherboard, a plurality of metal cross bars corresponding to the metal cooling box are fixedly connected between the two sides of the inner wall of the computer host housing, a hard disk installation box is fixedly connected to the front end of the top inner surface of the computer host housing, a cooling fan is installed at the bottom of the hard disk installation box, and a circuit board is arranged at the bottom of the cooling fan. In harsh application environments, such as operating under the two extreme ranges of -30 and 55°C, the liquid-cooled host has various system failures and unstable system operation during operation. Utility Model Content

[0004] The technical problem to be solved by the utility model is that the existing liquid cooling host cannot run at full load in harsh environments and the cooling capacity is insufficient. A storage liquid cooling unit with a precooling system is proposed. The unit is not affected by the ambient temperature during operation and can output cooling capacity at full power when the ambient temperature is high. There is no need to reduce the operating frequency of the refrigeration system compressor, which reduces the system operating pressure.

[0005] In order to solve the above technical problems, the technical solution adopted by the utility model is: a storage liquid cooling unit with a precooling system, comprising a unit shell, an electronic control unit is arranged in the unit shell, the electronic control unit is connected to a refrigeration module, the refrigeration module is provided with a refrigerator, the refrigerator is provided with a refrigerator frame, a precooler and a condenser which are fitted to each other are arranged in the refrigerator frame, and the width of the refrigerator fin is the sum of the width of the precooler fin and the width of the condenser fin.

[0006] A storage liquid cooling unit with a precooling system, a refrigeration module is arranged in the unit shell, the condenser and the precooler are arranged side by side to form a refrigerator, and the same fin-type design is adopted. On the one hand, the heat exchange area of ​​the condenser is increased to improve its heat exchange capacity, and on the other hand, the precooler and the condenser are in contact with each other for heat transfer, and the fins exchange heat with the circulating liquid with a lower temperature in the heat exchange tube, which greatly reduces the condensation temperature of the refrigeration system, and then reduces the condensation pressure of the refrigeration system. Therefore, the liquid cooling unit can operate at full load and provide sufficient cooling capacity.

[0007] Preferably, an air inlet is provided on one side of the unit housing, an air outlet is provided on the other side of the unit housing, and a plurality of fans are provided on one side of the air outlet. The air flow enters from the rear end, passes through the unit, first passes through the precooler, then passes through the condenser, and is discharged by the condensing fan.

[0008] Preferably, the refrigerator is close to the fan, one side of the condenser faces the fan, and one side of the precooler faces the air inlet. The precooler is installed behind the condenser to reduce the wind temperature passing through the precooler, thereby reducing the condensation pressure of the refrigeration system.

[0009] Preferably, a refrigerant inlet and a refrigerant outlet are provided on one side of the refrigerator, and a circulating liquid inlet and a circulating liquid outlet are provided on the other side of the refrigerator, the refrigerant inlet and the refrigerant outlet are connected to the condenser, and the circulating liquid inlet and the circulating liquid outlet are connected to the precooler. To facilitate pipeline layout, the header inlets and outlets of the precooler and the condenser are arranged on opposite sides.

[0010] Preferably, the unit housing on the air inlet side is provided with a water return port and a water outlet, the water return port is connected to the electronic control unit, and the water return port and the water outlet are used for the inlet and outlet of circulating liquid.

[0011] Preferably, the water return port is connected to an electric three-way valve, one outlet of the electric three-way valve is connected to the evaporator, the other outlet of the electric three-way valve is connected to the circulating liquid inlet, and the inlet of the electric three-way valve is connected to the circulating liquid outlet. The water system pipeline connects the precooler inlet and outlet to the water system circulation flow path through the electric three-way valve, and the water system flow direction is controlled by the electric three-way valve.

[0012] Preferably, a vertically arranged mounting bracket is provided in the middle of the unit housing, and the evaporator is fixed to the mounting bracket. The evaporator is used to absorb heat in the circulating fluid.

[0013] Preferably, the evaporator outlet is connected to the circulation pump inlet, the circulation pump inlet is provided with an expansion valve, the water outlet is connected to the circulation pump outlet, a heater is provided between the circulation pump outlet and the water outlet. The circulation pump drives the circulation fluid to circulate continuously to achieve continuous cooling.

[0014] Preferably, the evaporator outlet is connected to the compressor inlet, the compressor outlet is connected to the refrigerant inlet, and the refrigerant outlet is connected to the evaporator inlet. The compressor drives the refrigerant gas into the condenser for cooling, thereby achieving internal temperature discharge.

[0015] Preferably, a transverse fixing frame is provided on the top of the mounting bracket, and the electric control unit is fixed in the fixing frame. The electric control unit is installed on the top to fit the top plate, which is conducive to directly diffusing the temperature from the outside.

[0016] The substantial effects of the utility model are as follows: the precooler and the condenser of the utility model are arranged side by side, and the precooler is installed behind the condenser, which can reduce the wind temperature passing through the precooler, thereby reducing the condensing pressure of the refrigeration system; the precooler and the condenser adopt the same fin-type structure design, and the heat exchange area of ​​the precooler and the condenser can be increased when used independently, and the condensing pressure of the refrigeration system can be further reduced under the precooling conditions of high-temperature working conditions; when the ambient temperature is reduced to 0-30°C, the natural cold source can meet the cooling capacity of the circulating liquid, and the refrigeration system of the energy storage liquid cooling host does not need to be turned on, so there is no series of fault problems caused by the over-limit operation of the compressor during low-temperature operation; under the condition of abundant natural cold sources, the precooler can be used independently, and the refrigeration system does not need to be turned on, and only the circulation pump and the fan are consumed in operation, which greatly reduces the operating energy consumption of the energy storage liquid cooling unit and reduces the use cost; when the ambient temperature is 1-20°C, the precooler can still effectively precool the temperature of the returned circulating liquid, thereby reducing the cooling capacity required by the refrigeration system, thereby reducing the operating energy consumption of the refrigeration system, and playing a role in energy-saving operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a front view of the first embodiment.

[0018] Figure 2 It is an oblique rear view of the second embodiment.

[0019] Figure 3 This is a structural diagram of a refrigerator according to Embodiment 2.

[0020] Figure 4 This is a framework diagram of the circulation system of Example 3.

[0021] Among them: 1. Unit casing, 2. Electronic control unit, 3. Precooler, 4. Condenser, 5. Air inlet, 6. Air outlet, 7. Fan, 8. Expansion valve, 9. Electric three-way valve, 10. Circulation pump, 11. Evaporator, 12. Compressor, 13. Filter, 14. Heater, 15. Water return port, 16. Water outlet. DETAILED DESCRIPTION

[0022] The specific implementation of the utility model is further described below through specific embodiments and in conjunction with the accompanying drawings.

[0023] Embodiment one:

[0024] A liquid energy storage cooling unit with a precooling system, such as Figure 1 , Figure 2 and Figure 3 As shown, the unit housing 1 of the unit is composed of a refrigeration system, a water system, a precooler 3 and an electronic control unit 2.

[0025] The refrigeration system is a complete refrigeration system composed of a refrigeration compressor 12, a condenser 4, a condensing fan 7, an evaporator 11, a throttle valve and other equipment, pipelines, valves, etc. that constitute the refrigeration system.

[0026] The refrigeration system condenser 4 adopts a copper tube aluminum fin heat exchanger placed at the front end of the unit, the condensing fan 7 is arranged in front of the condenser 4, the evaporator 11 adopts a plate heat exchanger installed in the middle of the unit, and the compressor 12 and other components are installed at the bottom of the equipment.

[0027] The water system is a complete water system consisting of a circulation pump 10, an electric three-way valve 9, a precooler 3, an evaporator 11, a heater 14, and other pipes, equipment, valves, etc. connected to the water system.

[0028] The circulation pump 10, the compressor 12, the precooler 3 and the condenser 4 are fixed on the mounting base plate of the structural frame; the evaporator 11 adopts a plate heat exchanger and is mounted on a mounting bracket in the middle of the unit.

[0029] The precooler 3 also adopts a finned heat exchanger. The precooler 3 and the condenser 4 are arranged side by side and fixed with the same tube sheet. The precooler 3 and the condenser 4 use the same fins, that is, the fin width is the sum of the designed fin widths of the precooler 3 and the condenser 4. To facilitate pipeline layout, the header inlets and outlets of the precooler 3 and the condenser 4 are arranged on opposite sides.

[0030] There are sheet metal seals on both sides of the unit, and no air enters on both sides. The air flow enters from the rear air inlet 5, passes through the inside of the unit, first passes through the precooler 3 and then passes through the condenser 4, and is discharged by the condensing fan 7 at the air outlet 6.

[0031] The water system pipeline connects the inlet and outlet of the precooler 3 to the water system circulation flow path through the electric three-way valve 9, and the flow direction of the water system is controlled by the electric three-way valve 9.

[0032] The high-temperature circulating liquid returned from the terminal battery temperature control system is connected to the return port 15. The return port 15 pipeline is connected to the electric three-way valve. The two outlets of the electric three-way valve enter the plate heat exchanger in one way and the precooler in the other way. A three-way pipe fitting is provided between the electric three-way valve and the plate heat exchanger. The precooler outlet pipeline is connected to the plate heat exchanger inlet tee. The plate heat exchanger outlet pipeline is connected to the circulation pump inlet, and the circulation pump inlet is provided with an expansion valve 8. The circulation pump outlet is connected to the unit water outlet 16, and a pipeline electric heater is provided between the circulation pump outlet and the unit water outlet 16. The water outlet 16 is connected to the inlet of the terminal battery temperature control system to form a complete cycle.

[0033] The electronic control system is centrally controlled and divided into two control modes: manual and automatic. In the automatic mode, the refrigeration system, water system and precooler 3 can be automatically controlled according to the control strategy and actual conditions for automatic operation. In addition, in the automatic mode, the control system also has four major functions: refrigeration, heating, precooling and self-circulation.

[0034] like Figure 4 As shown, under non-harsh environmental conditions, only cooling or heating operation is performed. During cooling operation, the low-pressure refrigerant liquid absorbs the heat of the circulating liquid whose temperature rises after cooling and is supplied to the terminal battery temperature control system in the evaporator 11. The low-pressure refrigerant liquid evaporates into low-pressure refrigerant gas, and the heat of the circulating liquid is absorbed, the liquid temperature is reduced, and then the circulating liquid is pumped to the terminal battery temperature control system through the circulating pump 10 to cool the terminal battery temperature. The temperature of the terminal battery is cooled, and its own temperature rises and then circulated by the circulating pump 10 through the electric three-way valve 9 back to the evaporator 11. At the same time, the low-pressure refrigerant gas is sucked into the air intake port of the compressor 12, compressed into high-pressure superheated refrigerant gas through work, and discharged into the condenser 4 through the exhaust port of the compressor 12. The air is driven through the condenser 4 by the condensing fan 7. The high-pressure superheated refrigerant gas transfers heat to the air in the condenser 4 and condenses itself into a high-pressure refrigerant liquid. After passing through the liquid storage tank and the drying filter 13 from the outlet of the condenser 4 in sequence, it enters the throttle valve. The high-pressure refrigerant liquid is throttled and reduced in pressure to a low-pressure refrigerant liquid through the throttle valve, and then enters the evaporator 11 to absorb the heat of the circulating liquid and evaporate. This cycle continues, thereby realizing the temperature control of the battery temperature control system by the liquid cooling unit; when heating operation is required, the circulating liquid is heated by the electric heating of the water system, and when the circulating liquid temperature reaches the target temperature, the electric heater 14 is turned off.

[0035] When the ambient temperature is high, such as 50-55°C, the temperature of the circulating liquid returned by the battery temperature control system is about 20-30°C, which is much lower than the ambient temperature. The electronic control system turns on the precooling function, adjusts the direction of the electric three-way valve 9, controls the circulating liquid to enter the precooler 3 first, and precools the wind temperature passing through the precooler 3 so that its temperature when entering the condenser 4 is much lower than 50-55°C, thereby reducing the condensing pressure of the refrigeration system and avoiding the phenomenon of excessive system pressure during operation. The circulating liquid flows out of the outlet of the precooler 3 and enters the evaporator 11, where the heat is absorbed and the temperature is reduced. It is continuously circulated through the circulating pump 10 to achieve continuous cooling.

[0036] In addition, the condenser 4 and the precooler 3 are arranged side by side and adopt the same fin-type design. On the one hand, the heat exchange area of ​​the condenser 4 is increased and its heat exchange capacity is improved. On the other hand, the precooler 3 and the condenser 4 are in contact with each other for heat transfer. The fins exchange heat with the circulating liquid with a lower temperature in the heat exchange tube, which greatly reduces the condensation temperature of the refrigeration system and further reduces the condensation pressure of the refrigeration system. Therefore, the liquid cooling unit can operate at full load and provide sufficient cooling capacity.

[0037] When the ambient temperature is low, such as the ambient temperature of 0 to -30°C, and there are abundant outdoor cold sources, the precooling function can fully meet the current cooling demand. The electronic control system controls the refrigeration system compressor 12 to turn off, and the condensing fan 7 to turn on. Under the precooling function, the electric three-way valve 9 controls the circulating fluid to enter the precooler 3, and the heat of the circulating fluid is transferred to the air in the precooler 3. The temperature of the circulating fluid is lowered by the outdoor cold source, and then sent to the battery temperature control system by the circulating pump 10 for cooling. When operating under this condition, the refrigeration system does not need to be turned on, so there are no problems such as the over-limit operation of the refrigeration system compressor 12 under low temperature conditions, and the outdoor cold source is used for cooling, and only the power consumption of the condensing fan 7 and the circulating pump 10 needs to be borne, which greatly reduces the energy consumption of the equipment and reduces the operating cost.

[0038] In spring and autumn, when the ambient temperature is 1-20℃ (not limited), the outdoor cold source is not enough to fully support the energy storage liquid cooling host to independently complete the cooling and cooling of the circulating liquid through the precooler 3, but for the circulating liquid return temperature of 30-35℃, it still has certain heat exchange conditions. Under this working condition, the electronic control system can still turn on the precooling function, control the circulating liquid to enter the precooler 3 first through the electric three-way valve 9, and the condensing fan 7 drives the relatively low outdoor ambient air through the precooler 3 to reduce the temperature of the circulating liquid. Since the precooler 3 and the condenser 4 use the same fin structure design, the temperature of the circulating liquid whose temperature is reduced rises slightly, but is still lower than 30-35℃ when it returns. When the circulating liquid whose temperature is reduced by the precooler 3 enters the evaporator 11, the required cooling capacity is greatly reduced, and the refrigeration system can be operated at a reduced frequency according to its needs, which greatly reduces the operating energy consumption of the refrigeration system and reduces the equipment use cost.

[0039] Advantageously, the precooler 3 and the condenser 4 are arranged side by side, and the precooler 3 is installed behind the condenser 4, which can reduce the temperature of the wind passing through the precooler 3, thereby reducing the condensation pressure of the refrigeration system;

[0040] Advantageously, when the ambient temperature is high, the condensing fan 7 drives the air to pass through the precooler 3, and uses the returned circulating fluid to precool the high-temperature air in the precooler 3, thereby reducing its temperature when passing through the condenser 4, thereby reducing the condensation temperature of the refrigeration system and reducing the system operating pressure.

[0041] Furthermore, the precooler 3 and the condenser 4 adopt the same fin-type structural design, which can increase the heat exchange area of ​​the precooler 3 and the condenser 4 when used independently, and can further reduce the condensing pressure of the refrigeration system under the precooling condition of high temperature working condition; advantageously, under the low temperature working condition of -20~-30℃, the natural cold source can meet the cooling capacity of the circulating liquid, and the refrigeration system of the energy storage liquid cooling host does not need to be turned on, so there is no series of fault problems caused by the compressor 12 over-limit operation during low temperature operation;

[0042] In further low temperature conditions, the precooler 3 is used independently, and the refrigeration system does not need to be turned on, which greatly reduces the operating energy consumption of the energy storage liquid cooling unit and reduces the use cost;

[0043] Furthermore, in spring and autumn, when the ambient temperature is 5-20°C, the precooler 3 can still effectively precool the temperature of the returned circulating fluid, thereby reducing the cooling capacity required by the refrigeration system, and then reducing the operating energy consumption of the refrigeration system, thereby achieving energy-saving operation.

[0044] After the unit is turned on, the ambient temperature is detected. When the ambient temperature is 50>T ring>20℃, the unit operates normally for refrigeration. The low-pressure refrigerant liquid in the refrigeration system absorbs the heat of the circulating liquid whose temperature rises after being cooled by the terminal battery temperature control system in the evaporator 11. The low-pressure refrigerant liquid evaporates into low-pressure refrigerant gas. The heat of the circulating liquid is absorbed, and the liquid temperature is reduced. The circulating liquid is then pumped to the terminal battery temperature control system through the circulating pump 10 to cool the terminal battery temperature. The circulating liquid itself rises and is circulated by the circulating pump 10 through the electric three-way valve 9 back to the evaporator 11. At the same time, the low-pressure refrigerant gas is pumped into the evaporator 11 by the compressor. The gas is sucked in through the air inlet 12, compressed into high-pressure superheated refrigerant gas by doing work, and discharged into the condenser 4 through the exhaust port of the compressor 12. The air is driven through the condenser 4 by the condensing fan 7. The high-pressure superheated refrigerant gas transfers heat to the air in the condenser 4, and condenses itself into high-pressure refrigerant liquid. After passing through the liquid storage tank and the drying filter 13 from the outlet of the condenser 4 in sequence, it enters the throttle valve. The high-pressure refrigerant liquid is throttled and reduced in pressure to a low-pressure refrigerant liquid through the throttle valve, and then enters the evaporator 11 to absorb the heat of the circulating liquid and evaporate. This cycle continues, and the temperature control of the battery temperature control system by the liquid cooling unit is realized;

[0045] When the detected ambient temperature Tring ≥50℃ or 20>Tring ≥1℃, the unit will start refrigeration operation and turn on the precooling function. After the precooling function is turned on, the electronic control system will adjust the direction of the electric three-way valve 9 to control the circulating fluid to enter the precooler 3 first: when the ambient temperature Tring ≥50℃, the wind temperature passing through the precooler 3 is precooled by returning the relatively low-temperature circulating liquid, so that its temperature when entering the condenser 4 is much lower than 50-55℃, thereby reducing the condensing pressure of the refrigeration system and avoiding the phenomenon of excessive system pressure during operation. The circulating liquid flows out from the outlet of the precooler 3 and enters the evaporator 11, where heat is absorbed and the temperature is reduced. It is continuously circulated through the circulating pump 10 to achieve continuous cooling. When the ambient temperature is 20℃>Tring≥1℃, although the outdoor cold source is not enough to fully support the energy storage liquid cooling host to independently complete the cooling and cooling of the circulating liquid through the precooler 3, it still has certain heat exchange conditions for the circulating liquid return temperature of 30-35℃. The condensing fan 7 drives the relatively low outdoor ambient air to pass through the precooler 3 to reduce the temperature of the circulating liquid. Since the precooler 3 and the condenser 4 adopt the same fin structure design, the temperature of the circulating liquid with the lowered temperature rises slightly, but is still lower than 30-35℃ when returning. When the circulating liquid with the lowered temperature by the precooler 3 enters the evaporator 11, the required cooling capacity is greatly reduced, and the refrigeration system can be operated at a reduced frequency according to its needs, which greatly reduces the operating energy consumption of the refrigeration system and reduces the equipment use cost.

[0046] When the detected ambient temperature T ring is less than 0℃, the unit shuts down the refrigeration system and turns on the precooling function. At this time, the precooling function can fully meet the current cooling demand. Under the precooling function, the condensing fan 7 is turned on, and the electric three-way valve 9 controls the circulating fluid to enter the precooler 3. In the precooler 3, the heat of the circulating fluid is transferred to the air, and the temperature of the circulating fluid is lowered by the outdoor cold source, and then sent to the battery temperature control system by the circulating pump 10 for cooling.

[0047] When operating under this condition, the refrigeration system does not need to be turned on, so there will be no problems such as the refrigeration system compressor 12 exceeding the limit under low temperature conditions, and the outdoor cold source is used for cooling, and only the power consumption of the condensing fan 7 and the circulating pump 10 needs to be borne, which greatly reduces the energy consumption of the equipment and reduces the operating cost.

[0048] The above embodiments only express several implementation methods of the utility model, and the descriptions are relatively specific and detailed, but they cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model.

Claims

1. An energy storage liquid cooling unit with a precooling system, characterized in that: It includes a unit shell, in which an electric control unit is arranged, the electric control unit is connected to a refrigeration module, the refrigeration module is provided with a refrigerator, the refrigerator is provided with a refrigerator frame, the refrigerator frame is provided with a precooler and a condenser which fit each other, and the width of the refrigerator fin is the sum of the width of the precooler fin and the width of the condenser fin.

2. The energy storage liquid cooling unit with a precooling system according to claim 1, characterized in that: An air inlet is arranged on one side of the unit shell, an air outlet is arranged on the other side of the unit shell, and a plurality of fans are arranged on one side of the air outlet.

3. The energy storage liquid cooling unit with a precooling system according to claim 2, characterized in that: The refrigerator is close to the fan, one side of the condenser faces the fan, and one side of the precooler faces the air inlet.

4. The energy storage liquid cooling unit with a precooling system according to claim 2, characterized in that: A refrigerant inlet and a refrigerant outlet are provided on one side of the refrigerator, and a circulating liquid inlet and a circulating liquid outlet are provided on the other side of the refrigerator. The refrigerant inlet and the refrigerant outlet are connected to the condenser, and the circulating liquid inlet and the circulating liquid outlet are connected to the precooler.

5. The energy storage liquid cooling unit with a precooling system according to claim 4, characterized in that: The unit housing on one side of the air inlet is provided with a water return port and a water outlet, and the water return port is connected to the electronic control unit.

6. The energy storage liquid cooling unit with a precooling system according to claim 5, characterized in that: The water return port is connected to an electric three-way valve, one outlet of the electric three-way valve is connected to an evaporator, another outlet of the electric three-way valve is connected to the circulating liquid inlet, and the electric three-way valve inlet is connected to the circulating liquid outlet.

7. The energy storage liquid cooling unit with a precooling system according to claim 6, characterized in that: A vertically arranged mounting bracket is provided in the middle of the unit shell, and the evaporator is fixed to the mounting bracket.

8. The energy storage liquid cooling unit with a precooling system according to claim 6, characterized in that: The evaporator outlet is connected to the circulation pump inlet, the circulation pump inlet is provided with an expansion valve, the water outlet is connected to the circulation pump outlet, and a heater is provided between the circulation pump outlet and the water outlet.

9. The energy storage liquid cooling unit with a precooling system according to claim 6, 7 or 8, characterized in that: The evaporator outlet is connected to the compressor inlet, the compressor outlet is connected to the refrigerant inlet, and the refrigerant outlet is connected to the evaporator inlet.

10. The energy storage liquid cooling unit with a precooling system according to claim 7, characterized in that: A transverse fixing frame is provided on the top of the mounting bracket, and the electronic control unit is fixed in the fixing frame.

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