Refrigerant direct cooling and liquid cooling fusion cooling system

Abstract

The utility model discloses a refrigerant direct cooling and liquid cooling fusion cooling system, and aims to overcome the defects of high energy consumption, poor cooling performance and use cost increase of a cooling system in the prior art. The technical problem is solved through the following technical scheme: the battery pack cooling system comprises a refrigerating system, a water system for cooling a battery pack and a refrigerant direct cooling system, the water system comprises an evaporator, a circulating pump and a pipeline water electric heater, the refrigerating system comprises a liquid storage tank and a condenser; two ends of the liquid storage tank are respectively connected with the condenser and the evaporator, and an electronic expansion valve is arranged between the evaporator and the liquid storage tank; the refrigerant direct cooling system comprises a power module cooling cold plate, an evaporation pressure regulating valve and an electromagnetic valve; one end of the power cooling cold plate communicates with the liquid storage tank, the other end of the power cooling cold plate communicates with the evaporation pressure regulating valve, and the electromagnetic valve is arranged between the power module cooling cold plate and the liquid storage tank; and one end of the evaporation pressure regulating valve far away from the power module cooling is communicated with an air suction pipe of the refrigeration system.

Description

Technical Field

[0001] The utility model relates to the technical field of battery cooling, and more specifically, to a cooling system combining refrigerant direct cooling and liquid cooling. Background Art

[0002] At present, the thermal management modes for large-scale and industrial and commercial energy storage are generally: battery PACK liquid cooling + PCS air cooling and battery PACK liquid cooling + PCS liquid cooling; similarly, the above two modes are also used for cooling battery PACKs and power modules in the charging and swapping field.

[0003] The specific technical solutions are: 1. "Dual-circuit liquid cooling system", the main circuit and branch circuit share the same water system and refrigeration system. The main circuit cools the battery PACK, and the branch circuit cooperates with fan coil units or cold plates to cool PCS, power modules and other equipment; 2. "Independent dual-circuit liquid cooling system", the difference is that the circuit for cooling PCS or power modules is a completely independent liquid cooling system, which is independently equipped with major components such as circulating pumps and heat exchangers, and is not equipped with a refrigeration system, but the heat is eventually discharged from the main circuit through the refrigeration system.

[0004] However, the above technical solution does have the following defects: 1. The essential problem of the "dual-circuit liquid cooling system" is that the cooling temperature of the battery pack is relatively low, and condensation will occur when the same liquid outlet temperature is supplied to the PCS or power module, which does not meet the electrical safety requirements; 2. The branch water temperature of the "independent dual-circuit liquid cooling system" is higher, which solves the problem of condensation on the PCS or power module, but the equipment of an additional water system greatly increases the equipment cost and is more expensive; "dual-circuit liquid cooling system" and "independent dual-circuit liquid cooling system" both use indirect cooling systems, and the surface temperature is uneven. This uneven temperature distribution is not conducive to the heat dissipation and cooling of electronic power components with relatively high uniformity requirements.

[0005] The Chinese patent publication number is CN220272596U, the publication date is December 27, 2023. The application is named as a circulating mixed flow liquid cooling system. The application discloses a cooling method using double circulation or multi-circulation mixed flow to avoid the situation where a certain circuit is not cooled. However, the above structure consumes more energy, which increases the cost of use. Utility Model Content

[0006] The utility model overcomes the shortcomings of the cooling system in the prior art, such as high energy consumption, poor cooling performance and increased use cost, and provides a cooling system that combines refrigerant direct cooling and liquid cooling. It can reduce operating energy consumption, thereby reducing use costs, and can also improve cooling efficiency, making surface heat dissipation more uniform; it can also reduce the problem of condensation during power module cooling and improve the safety performance of the equipment.

[0007] In order to solve the above technical problems, the utility model adopts the following technical solutions: a cooling system integrating refrigerant direct cooling and liquid cooling, comprising: a refrigeration system, a water system for cooling the battery pack, and a refrigerant direct cooling system;

[0008] The water system includes an evaporator and a circulation pump and a pipeline water electric heater connecting both ends of the evaporator;

[0009] The refrigeration system includes a liquid storage tank and a condenser; the two ends of the liquid storage tank are connected to the condenser and the evaporator respectively, and an electronic expansion valve is arranged between the evaporator and the liquid storage tank;

[0010] The refrigerant direct cooling system includes a power module cooling cold plate, an evaporating pressure regulating valve and a solenoid valve; one end of the power cooling cold plate is connected to a liquid storage tank and the other end is connected to the evaporating pressure regulating valve, and the solenoid valve is arranged between the power module cooling cold plate and the liquid storage tank; the end of the evaporating pressure regulating valve away from the power module cooling is connected to the suction pipe of the refrigeration system.

[0011] The refrigerant direct cooling and liquid cooling fusion cooling system in the utility model can realize a set of refrigeration system and a set of water system to cool the battery pack and the power module at the same time. The high-pressure liquid refrigerant phase change direct cooling has no condensation risk and does not require the configuration of additional water systems and ancillary equipment, which reduces equipment costs and consumes no other power equipment during operation, greatly improving operating energy efficiency.

[0012] Preferably, a heat regenerator is provided between the solenoid valve and the power module cooling cold plate.

[0013] The establishment of the regenerator can not only offset the excessive supercooling, but also reduce the condensation heat exchange burden on the refrigeration system condenser and reduce the required cooling area of ​​the refrigeration system condenser. The regenerator uses superheated refrigerant gas as a heat source, and does not require other power output during use, and there is no additional operating energy consumption.

[0014] Preferably, the heat regenerator is provided with two paths, one of which is connected to the power cooling module and the liquid storage tank; the other path of the heat regenerator is connected to the exhaust pipe of the refrigeration system and the condenser.

[0015] During the operation of the direct cooling system, there is no power consumption of other circulating pumps and other equipment. The regenerator uses superheated refrigerant gas as a heat source. No other power output is required during use, and there is no additional operating energy consumption, which greatly improves the operating energy efficiency.

[0016] Preferably, the water system further comprises an automatic liquid replenishing system, which comprises a water replenishing tank and a liquid replenishing water pump, and a check valve is arranged between the liquid replenishing water pump and the water system.

[0017] The water in the water replenishment tank can flow into the water system in one direction. Through the action of the water replenishment tank and the replenishment water pump, the circulating fluid can be automatically replenished for the water system.

[0018] Preferably, a water temperature sensor is also provided in the water system.

[0019] Used to detect the temperature of circulating fluid in the water system.

[0020] Preferably, the water system is connected to the battery pack, and pressure sensors are provided at the water inlet and outlet of the battery pack.

[0021] Used to detect changes in pressure at the water inlet and outlet of the battery pack.

[0022] Preferably, the refrigeration system also includes an air flow separator and a compressor, one end of the air flow separator is connected to the compressor, and the other end of the air flow separator is connected between the evaporation pressure regulating valve and the solenoid valve; the other end of the compressor is connected to the condenser or the regenerator.

[0023] At the same time, low-pressure refrigerant gas is sucked into the compressor suction port, compressed into high-pressure superheated refrigerant gas through work, and discharged into the condenser through the compressor exhaust port, and the air is driven through the condenser by the condensing fan.

[0024] Preferably, an electric three-way valve is also included, and the electric three-way valve is connected to the compressor, the condenser and the heat regenerator respectively.

[0025] The electric three-way valve can control the bypass volume. The higher the subcooling degree, the greater the bypass volume, and vice versa, the bypass valve will be closed.

[0026] Compared with the prior art, the beneficial effects of the utility model are:

[0027] (1) The refrigerant direct cooling system uses the liquid refrigerant flowing out of the liquid storage tank without reducing the pressure to directly cool the liquid by phase change. The evaporation temperature is high, which effectively solves the condensation problem during PCS / power module cooling.

[0028] (2) The refrigerant direct cooling system adjusts the subcooling degree of the refrigerant liquid at the cold plate inlet to avoid the temperature gradient along the refrigerant flow direction caused by the sensible heat exchange of the supercooled liquid after entering the cold plate;

[0029] (3) The refrigerant direct cooling system is adopted, which does not require additional water circuit configuration, and does not require configuration of water circuit components such as circulating pumps and heat exchangers, greatly reducing equipment costs;

[0030] (4) During the operation of the refrigerant direct cooling system, there is no power consumption of other circulating pumps and other equipment. The regenerator uses superheated refrigerant gas as a heat source. During use, no other power output is required and there is no additional operating energy consumption, which greatly improves the operating energy efficiency.

[0031] (5) The establishment of the regenerator can not only offset the excessive supercooling, but also reduce the condensation heat exchange burden on the condenser of the refrigeration system and reduce the required cooling area of ​​the condenser of the refrigeration system;

[0032] (6) The refrigerant direct cooling system utilizes the latent heat of refrigerant phase change evaporation, which can provide a more efficient, stable and uniform heat exchange effect. At the same time, it is safer to operate, smaller in size and more flexible. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the operating structure of the utility model.

[0034] Figure 2 It is a schematic diagram of the water system structure of the utility model.

[0035] Figure 3 It is a schematic diagram of the refrigerant direct cooling system structure of the utility model.

[0036] In the figure: 1. Water system, 11. Circulation pump, 12. Evaporator, 13. Pipeline water heater, 14. Battery pack, 15. Water temperature sensor, 16. Pressure sensor;

[0037] 2. Refrigeration system, 21. Liquid storage tank, 22. Condenser, 23. Compressor, 24. Condensing fan, 25. Gas-liquid separator, 26. Electronic expansion valve, 27. Electric three-way valve;

[0038] 3. Refrigerant direct cooling system, 31. Solenoid valve, 32. Power module cooling cold plate, 33. Evaporation pressure regulating valve, 34. Regenerator;

[0039] 4. Automatic liquid replenishing system, 41. Water replenishing tank, 42. Liquid replenishing water pump, 43. Check valve. DETAILED DESCRIPTION

[0040] The technical solution of the present invention is further described in detail below through specific embodiments and in conjunction with the accompanying drawings:

[0041] Example 1: Reference Figures 1 to 3 As shown, a cooling system combining refrigerant direct cooling and liquid cooling includes: a refrigeration system 2, a water system 1 for cooling a battery pack 14, and a refrigerant direct cooling system 3. In addition, an electronic control system is included to control the normal operation of the refrigeration system 2, the water system 1, and the refrigerant direct cooling system 3.

[0042] The water system 1 includes a circulation pump 11, an evaporator 12, a pipeline hydroelectric heater 13, and other pipeline equipment valves connected to the water system 1. The water system 1 is connected to the battery pack 14 for cooling the battery pack 14. The two ends of the evaporator 12 are respectively connected to the circulation water pump and the pipeline hydroelectric heater 13. The water system 1 also includes an automatic refilling system 4, which includes a water replenishing tank 41 and a refilling water pump 42. A check valve 43 is provided between the refilling water pump and the water system 1. Through the action of the water replenishing tank 41 and the refilling water pump 42, the circulating liquid can be automatically replenished for the water system 1. A water temperature sensor 15 is also provided in the water system 1. Pressure sensors 16 are provided at the water inlet and outlet of the battery pack 14.

[0043] The refrigeration system 2 includes a liquid storage tank 21, a condenser 22, a compressor 23, a condensing fan 24, an evaporator 12, an electronic expansion valve 26, a gas-liquid separator 25 and other structures. The two ends of the liquid storage tank 21 are respectively connected to the condenser 22 and the evaporator 12, and an electronic expansion valve 26 is arranged between the evaporator 12 and the liquid storage tank 21. The condenser 22 is connected to the liquid storage pipe, and the condenser 22 and the condensing fan 24 are used in conjunction. The end of the condensing fan 24 away from the liquid storage tank 21 is connected to the compressor 23 and the air flow separator in turn, and then connected to the evaporator 12 again.

[0044] The refrigerant direct cooling system 3 includes a solenoid valve 31, a power module cooling plate 32 and an evaporation pressure regulating valve 33 connected in sequence. One end of the power cooling plate is in communication with the liquid storage tank 21, and the other end is in communication with the evaporation pressure regulating valve 33. The solenoid valve 31 is arranged between the power module cooling plate 32 and the liquid storage tank 21. The end of the evaporation pressure regulating valve 33 away from the power module cooling is in communication with the suction pipe of the refrigeration system 2, and the suction pipe of the refrigeration system 2 is a pipe connecting the evaporator 12 and the gas-liquid separator 25.

[0045] The working principle of the utility model is as follows:

[0046] (1) When only the battery pack 14 is cooled (see Figure 2As shown in the figure, a low-pressure refrigerant liquid is arranged in the evaporator 12. The low-pressure refrigerant liquid absorbs the heat of the circulating liquid whose temperature rises in the water system 1 after being supplied to the terminal battery temperature control system for cooling in the evaporator 12, and evaporates the low-pressure refrigerant liquid into a low-pressure refrigerant gas. The heat of the circulating liquid in the water system 1 is absorbed, and the liquid temperature of the circulating liquid is reduced. The circulating liquid is then pumped to the terminal battery temperature control system by the circulating pump 11 to cool the terminal battery temperature. The temperature of the terminal battery is cooled, and the circulating liquid itself is circulated back to the evaporator 12 by the circulating pump 11 after its own temperature rises. At the same time, the low-pressure refrigerant gas is sucked into the air intake port of the compressor 23, and is compressed into a high-pressure superheated gas by doing work. The refrigerant gas is discharged into the condenser 22 through the exhaust port of the compressor 23, and the air is driven through the condenser 22 by the condensing fan 24. The high-pressure superheated refrigerant gas transfers heat to the air in the condenser 22, and condenses itself into a high-pressure refrigerant liquid. After passing through the liquid storage tank 21 from the outlet of the condenser 22, it enters the electronic expansion valve 26. The high-pressure refrigerant liquid is throttled and reduced in pressure to a low-pressure refrigerant liquid through the electronic expansion valve 26, and then enters the evaporator 12 to absorb the heat of the circulating liquid and evaporate, and then enters the air intake port of the compressor 23 through the gas-liquid separator 25. This cycle continues, thereby realizing the temperature control of the battery temperature control system by the liquid cooling unit.

[0047] (2) When the battery pack + PCS / power module is running in cooling mode, refer to Figure 2 , Figure 3 As shown, the refrigeration system 2 and the water system 1 operate according to the above process. When the control system detects that the PCS / power module has a cooling demand, the solenoid valve 31 of the refrigerant direct cooling system 3 is opened, and the liquid refrigerant in the liquid storage tank 21 enters the power module cooling plate 32 through the solenoid valve 31. The liquid refrigerant absorbs the heat of the power module in the power module cooling plate 32, and the temperature of the power module decreases. The refrigerant liquid itself evaporates into refrigerant gas, and passes through the evaporation pressure regulating valve 33 from the outlet of the power module cooling plate 32. The outlet pressure is adjusted to be consistent with the suction pipe of the refrigeration system through the evaporation pressure regulating valve 33, and then passes through the gas-liquid separator 25 together with the refrigerant gas at the outlet of the evaporator 12 of the refrigeration system 2, and then enters the refrigeration compressor 23.

[0048] In specific operation, when a cooling demand or a startup instruction is detected, the electronic control system controls the water system 1 circulation pump 11 to start first, and after a delay of 60s, the condensing fan 24 and the electronic expansion valve 26 are turned on, and the compressor 23 is turned on after a delay of 60s. The refrigeration system 2 controls the frequency increase or decrease or stops the refrigeration system 2 according to the outlet temperature of the water system 1. The condensing fan 24 automatically controls the fan speed to increase or decrease according to the saturation temperature of the condenser 22. The electronic expansion valve 26 automatically controls the opening of the electronic expansion valve 26 according to the outlet superheat of the evaporator 12 of the refrigeration system 2. The circulation of the refrigeration system 2 and the water system 1 is not repeated; when the electronic control system detects that the pcs side When there is a cooling demand, the liquid supply solenoid valve 31 of the refrigerant direct cooling system 3 is opened, and the refrigerant liquid enters the power module cooling plate 32 through the regenerator 34 under the drive of the pressure difference. The refrigerant liquid evaporates in the power module cooling plate 32 to absorb the heat of the power module. The temperature of the power module drops, and the refrigerant liquid evaporates into refrigerant gas. After passing through the evaporation pressure regulating valve 33, the outlet pressure is automatically adjusted to be consistent with the outlet pressure of the evaporator 12 of the refrigeration system 2, and enters the gas-liquid separator 25 together with it. After gas-liquid separation, it is sucked into the compressor 23, and it circulates continuously in this way to realize the cooling of the battery pack 14 and the PCS or power module by combining the refrigerant and liquid cooling;

[0049] The solenoid valve 31 of the refrigerant direct cooling system 3 can control the on and off of the refrigerant direct cooling system 3 on the one hand, and is in a normally closed state when the PCS has no cooling demand. At the same time, the duty ratio of the opening of the solenoid valve 31 can be used to control the flow of the liquid refrigerant in the refrigerant direct cooling system 3, and then control the cooling load of the power module cooling plate 32, thereby realizing the temperature control of the PCS or the power module;

[0050] The electric three-way valve 27 of the refrigerant direct cooling system 3 controls the opening of the three-way valve and then controls the bypass volume of the superheated gas according to the set target subcooling, thereby realizing the control of the subcooling of the refrigerant liquid. When the subcooling is too high, the opening of the three-way valve is opened, otherwise the opening of the three-way valve is closed.

[0051] The beneficial effects of the utility model are:

[0052] First, the refrigerant direct cooling system uses the liquid refrigerant flowing out of the liquid storage tank without depressurization to directly cool the liquid through phase change. The evaporation temperature is high, which effectively solves the condensation problem during PCS / power module cooling.

[0053] Second, the refrigerant direct cooling system adjusts the supercooling degree of the refrigerant liquid at the cold plate inlet to avoid the temperature gradient along the refrigerant flow direction caused by the sensible heat exchange of the supercooled liquid after entering the cold plate;

[0054] Third, the refrigerant direct cooling system does not require additional water circuit configuration, and does not require configuration of water circuit components such as circulating pumps and heat exchangers, which greatly reduces equipment costs;

[0055] Fourth, during the operation of the refrigerant direct cooling system, there is no other power consumption of circulating pumps and other equipment. The regenerator uses superheated refrigerant gas as a heat source. During use, no other power output is required, and there is no additional operating energy consumption, which greatly improves the operating energy efficiency.

[0056] Fifth, the refrigerant direct cooling system utilizes the latent heat of refrigerant phase change evaporation, which can provide a more efficient, stable and uniform heat exchange effect. At the same time, its operation is safer, smaller in size and more flexible.

[0057] Example 2: Reference Figures 1 to 3 As shown, the structure of this embodiment is similar to that of embodiment 1, except that a regenerator 34 is provided between the refrigerant direct cooling system 3 and the refrigeration system 2 .

[0058] One end of the regenerator 34 away from the power module cooling cold plate 32 is connected to the liquid storage tank 21, and one end of the power module cooling cold plate 32 away from the regenerator 34 is connected to the evaporator 12. An evaporation pressure regulating valve 33 is also provided between the evaporator 12 and the power cooling module. The regenerator 34 is provided with two paths, one of which is connected to the power cooling module and the liquid storage tank 21, and a solenoid valve 31 is provided between the liquid storage tank 21 and the power cooling module; the other path of the regenerator 34 is connected to the exhaust pipe of the refrigeration system 2 and the condenser 22.

[0059] The electric three-way valve 27 is respectively connected to the compressor 23, the condenser 22 and the regenerator 34. The electric three-way valve 27 is used to control the bypass amount of the refrigerant flowing out of the condenser 22 through the reflux valve.

[0060] A reheater 34 is provided between the refrigerant direct cooling system 3 and the refrigeration system 2. The temperature uniformity of the surface of the power module cooling plate 32 is improved by controlling the inlet supercooling of the power module cooling plate 32. The inlet supercooling of the power module cooling plate 32 is detected in real time. When the inlet supercooling is higher than the set target, the electric three-way valve 27 is opened to control the bypass amount. The higher the supercooling, the greater the bypass amount. Otherwise, the bypass valve is closed.

[0061] The beneficial effects of this embodiment are as follows:

[0062] The regenerator 34 before the entrance of the power module cooling plate 32 can effectively control the supercooling degree of the liquid refrigerant, and avoid the temperature gradient along the flow direction of the refrigerant caused by the sensible heat exchange of the supercooled liquid after entering the power module cooling plate 32. In addition, the establishment of the regenerator 34 can reduce the condensation heat exchange burden on the condenser 22 of the refrigeration system 2 while offsetting the excessive supercooling, and reduce the required cooling area of ​​the condenser 22 of the refrigeration system 2.

[0063] The regenerator 34 utilizes the superheated refrigerant gas as a heat source and does not require any other power output during use, and thus does not consume any additional operating energy.

[0064] The refrigerant direct cooling system 3 adopts the phase change direct cooling of the undepressurized liquid refrigerant flowing out of the liquid storage tank 21, with a high evaporation temperature and no condensation problem. In addition, the refrigerant direct cooling system 3 does not require additional water circuit configuration, and does not require configuration of water circuit components such as circulating pumps and heat exchangers, which greatly reduces the equipment cost. During the operation of the refrigerant direct cooling system 3, there is no consumption of power equipment such as other circulating pumps, which greatly improves the operating energy efficiency. The refrigerant direct cooling system 3 utilizes the latent heat of evaporation of the refrigerant phase change, which can provide a more efficient, more stable and more uniform heat exchange effect. At the same time, its operation is safer, the size is smaller, and the flexibility is higher.

[0065] The above-described embodiments are only preferred solutions of the present invention and are not intended to limit the present invention in any form. Other variations and modifications are possible without exceeding the technical solutions described in the claims.

Claims

1. A cooling system combining direct cooling of refrigerant and liquid cooling, characterized in that: include: Refrigeration system, water system for cooling the battery pack and refrigerant direct cooling system; The water system includes an evaporator and a circulation pump and a pipeline water electric heater connecting both ends of the evaporator; The refrigeration system includes a liquid storage tank and a condenser; the two ends of the liquid storage tank are connected to the condenser and the evaporator respectively, and an electronic expansion valve is arranged between the evaporator and the liquid storage tank; The refrigerant direct cooling system includes a power module cooling cold plate, an evaporating pressure regulating valve and a solenoid valve; one end of the power cooling cold plate is connected to a liquid storage tank and the other end is connected to the evaporating pressure regulating valve, and the solenoid valve is arranged between the power module cooling cold plate and the liquid storage tank; the end of the evaporating pressure regulating valve away from the power module cooling is connected to the suction pipe of the refrigeration system.

2. The cooling system combining direct cooling with liquid cooling according to claim 1 is characterized in that: A heat regenerator is arranged between the solenoid valve and the power module cooling cold plate.

3. The cooling system combining direct cooling with liquid cooling according to claim 2 is characterized in that: The heat regenerator is provided with two paths, one of which is connected to the power cooling module and the liquid storage tank; the other path of the heat regenerator is connected to the exhaust pipe of the refrigeration system and the condenser.

4. The cooling system according to any one of claims 1 to 3, characterized in that: The water system also includes an automatic liquid replenishing system, which includes a water replenishing tank and a liquid replenishing water pump. A check valve is arranged between the liquid replenishing water pump and the water system.

5. The cooling system according to any one of claims 1 to 3, characterized in that: A water temperature sensor is also provided in the water system.

6. The cooling system combining direct cooling with liquid cooling according to claim 5 is characterized in that: The water system is connected to the battery pack, and pressure sensors are provided at the water inlet and outlet of the battery pack.

7. The cooling system combining direct cooling with liquid cooling according to claim 3 is characterized in that: The refrigeration system also includes an air flow separator and a compressor. One end of the air flow separator is connected to the compressor, and the other end of the air flow separator is connected between the evaporation pressure regulating valve and the solenoid valve; the other end of the compressor is connected to the condenser or the regenerator.

8. The cooling system combining direct cooling with liquid cooling according to claim 7 is characterized in that: It also includes an electric three-way valve, which is connected to the compressor, the condenser and the heat regenerator respectively.

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