Hybrid thermal management system

Abstract

This utility model relates to the field of thermal management technology, and more particularly to a hybrid thermal management system, including a liquid-cooled circulation loop containing a liquid cooling medium. The liquid-cooled circulation loop includes a first pipe and a second pipe that are connected in a circulating manner. A liquid-cooled heat exchanger is installed on the first pipe to absorb heat from the battery. The second pipe includes a liquid-cooled branch and an air-cooled branch connected in series or parallel. A liquid chiller is installed on the liquid-cooled branch, and an air-cooled dry cooler is installed on the air-cooled branch. This hybrid thermal management system, by simultaneously setting up liquid-cooled and air-cooled branches, can shut down the liquid chiller or reduce its power when the ambient temperature is low, and increase the fan power of the air-cooled dry cooler as needed to fully utilize the ambient temperature cooling capacity and improve energy efficiency. This hybrid thermal management system can also fully utilize the heat absorbed by the liquid chiller under high-rate charge and discharge conditions to meet the high heat dissipation requirements under these conditions.

Description

Technical Field

[0001] This utility model relates to the field of thermal management technology, and in particular to a hybrid thermal management system. Background Technology

[0002] Most mobile energy storage systems are equipped with either liquid-cooled or air-cooled thermal management systems. However, the ambient temperature varies significantly in different operating regions. In areas with low ambient temperatures, liquid-cooled thermal management systems cannot directly and efficiently utilize the ambient cooling capacity, resulting in low overall system heat exchange efficiency. In areas with high ambient temperatures, air-cooled thermal management systems cannot fully meet the high heat dissipation demands under high-rate charge and discharge conditions, thus limiting the operating conditions of mobile energy storage systems. Utility Model Content

[0003] The purpose of this invention is to provide a hybrid thermal management system that can efficiently utilize ambient temperature cooling capacity and meet the high heat dissipation requirements under high-rate charging and discharging conditions.

[0004] To achieve this objective, the present invention adopts the following technical solution:

[0005] A hybrid thermal management system is provided, including a liquid-cooled circulation loop containing a liquid cooling medium. The liquid-cooled circulation loop includes a first pipe and a second pipe that are circulated and connected. A liquid-cooled heat exchanger is provided on the first pipe for absorbing heat from a battery. The second pipe includes a liquid-cooled branch and an air-cooled branch connected in series or in parallel. A liquid chiller is provided on the liquid-cooled branch, and an air-cooled dry cooler is provided on the air-cooled branch.

[0006] Optionally, it also includes a direct cooling circulation loop, which contains a cooling medium. The direct cooling circulation loop includes a first compressor, a first condenser, a first throttle valve, and a direct cooling heat exchanger connected in sequence. The direct cooling heat exchanger is used to absorb the heat from the liquid-cooled heat exchanger.

[0007] Optionally, the direct cooling cycle loop further includes a first gas-liquid separator, which is disposed between the first compressor and the direct cooling heat exchanger.

[0008] Optionally, the flow direction of at least a portion of the direct cooling flow channel of the direct cooling heat exchanger is opposite to the flow direction of at least a portion of the liquid cooling flow channel of the liquid cooling heat exchanger.

[0009] Optionally, the direct cooling loop further includes a first fan, which is used to increase the airflow velocity at the first condenser.

[0010] Optionally, the liquid cooler includes a first heat exchanger, a first side of which is connected to the liquid cooling branch, and a second side of which is connected in parallel with the direct cooling heat exchanger.

[0011] Optionally, the liquid chiller includes an internal circulation loop, which includes a first side of a second heat exchanger, a second compressor, a second condenser, and a second throttle valve connected in sequence, with the second side of the second heat exchanger connected to the liquid cooling branch.

[0012] Optionally, the liquid chiller further includes a second fan for increasing the airflow velocity at the second condenser.

[0013] Optionally, the liquid cooling circulation loop further includes a first regulating valve, wherein the liquid cooling branch and the air cooling branch are arranged in parallel, and the first regulating valve is used to regulate the flow rate of the liquid cooling medium in the liquid cooling branch and the air cooling branch.

[0014] Optionally, the liquid cooling circulation loop further includes a circulation pump, which is disposed on the first pipeline.

[0015] The beneficial effects of this utility model are:

[0016] This invention provides a hybrid thermal management system, including a liquid-cooled circulation loop containing a liquid cooling medium. The liquid-cooled circulation loop includes a first pipe and a second pipe connected in a circulating manner. A liquid-cooled heat exchanger is installed on the first pipe to absorb heat from the battery. The second pipe includes a liquid-cooled branch and an air-cooled branch connected in series or parallel. A liquid-cooled chiller is installed on the liquid-cooled branch, and an air-cooled dry cooler is installed on the air-cooled branch. By simultaneously setting up liquid-cooled and air-cooled branches, this hybrid thermal management system can shut down or reduce the power of the liquid chiller when the ambient temperature is low, and increase the fan power of the air-cooled dry cooler as needed to fully utilize the ambient cooling capacity and improve energy efficiency. This hybrid thermal management system can also fully utilize the heat absorbed by the liquid chiller under high-rate charge and discharge conditions to meet the high heat dissipation requirements of such conditions. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the hybrid thermal management system provided in this embodiment of the present invention;

[0018] Figure 2 This is a schematic diagram of the structure of the hybrid thermal management system (including a first heat exchanger) provided in an embodiment of the present invention;

[0019] Figure 3 This is a schematic diagram of the structure of the hybrid thermal management system (including a second heat exchanger) provided in an embodiment of the present invention.

[0020] In the picture:

[0021] 1. Liquid-cooled heat exchanger; 2. Liquid chiller; 21. First heat exchanger; 22. Second heat exchanger; 23. Second compressor; 24. Second condenser; 25. Second throttle valve; 26. Second fan; 27. Second gas-liquid separator;

[0022] 3. Air-cooled dry cooler; 31. Third fan; 4. First compressor; 5. First condenser; 6. First throttle valve; 7. Direct cooling heat exchanger; 8. First gas-liquid separator; 9. First fan; 10. First regulating valve; 11. Circulating pump; 12. First temperature sensor; 13. Second regulating valve; 14. Second temperature sensor;

[0023] 900, battery. Detailed Implementation

[0024] The technical solution of this utility model will be further described below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for explaining this utility model and not for limiting it. Furthermore, it should be noted that, for ease of description, only the parts related to this utility model are shown in the drawings, not all of them.

[0025] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0026] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0027] like Figures 1-3As shown, the hybrid thermal management system of this embodiment includes a liquid-cooled circulation loop containing a liquid cooling medium. The liquid-cooled circulation loop includes a first pipe and a second pipe that are connected in a circulation manner. A liquid-cooled heat exchanger 1 is provided on the first pipe, and a liquid-cooled flow channel in the liquid-cooled heat exchanger 1 is connected to the first pipe. The liquid-cooled heat exchanger 1 is used to absorb the heat of the battery 900. The second pipe includes a liquid-cooled branch and an air-cooled branch that are connected in series or in parallel. A liquid chiller 2 is provided on the liquid-cooled branch, and an air-cooled dry cooler 3 is provided on the air-cooled branch.

[0028] This hybrid thermal management system, by simultaneously configuring liquid-cooled and air-cooled branches, can shut down or reduce the power of liquid chiller 2 when the ambient temperature is low, while increasing the fan power of air-cooled dry cooler 3 as needed, to fully utilize the ambient cooling capacity and improve energy efficiency. This hybrid thermal management system can also fully utilize the heat absorbed by liquid chiller 2 under high-rate charge / discharge conditions to meet the high heat dissipation requirements under these conditions. It should be noted that the fan of air-cooled dry cooler 3 is the third fan 31 shown in the diagram.

[0029] Optionally, the liquid cooling circulation loop also includes a first regulating valve 10. The liquid cooling branch and the air cooling branch are connected in parallel. The first regulating valve 10 is used to regulate the flow rate of the liquid cooling medium in the liquid cooling branch and the air cooling branch. That is, part of the liquid cooling medium flows through the liquid chiller 2 to absorb cold energy and lower the temperature, and part of the liquid cooling medium flows through the air-cooled dry cooler 3 to release heat. Of course, with the adjustment of the first regulating valve 10, all the liquid cooling medium can also flow into the liquid cooling branch to absorb cold energy and lower the temperature at the liquid chiller 2, or all the liquid cooling medium can flow into the air cooling branch to release heat at the air-cooled dry cooler 3.

[0030] Optionally, the liquid cooling circulation loop also includes a circulation pump 11, which is installed on the first pipeline to provide power for the flow of the liquid cooling medium in the liquid cooling circulation loop.

[0031] Optionally, the liquid cooling circulation loop further includes a first temperature sensor 12, which is used to test the temperature of the liquid cooling medium in the pipe upstream of the liquid cooling heat exchanger 1, i.e., the inlet temperature. Optionally, the liquid cooling circulation loop further includes a second temperature sensor 14, which is used to measure the temperature of the liquid cooling medium in the pipe downstream of the liquid cooling heat exchanger 1, i.e., the outlet temperature.

[0032] Optionally, the hybrid thermal management system further includes a direct cooling loop containing a cooling medium. The direct cooling loop includes a first compressor 4, a first condenser 5, a first throttle valve 6, and a direct cooling heat exchanger 7 connected in sequence. The direct cooling heat exchanger 7 absorbs heat from the liquid-cooled heat exchanger 1. By setting up the direct cooling loop, the temperature of the liquid-cooled heat exchanger 1 can be further reduced, achieving rapid and sufficient heat dissipation of the battery 900 under high-rate charge and discharge conditions.

[0033] Optionally, the direct cooling circulation loop also includes a first gas-liquid separator 8, which is disposed between the first compressor 4 and the direct cooling heat exchanger 7 to protect the first compressor 4.

[0034] Optionally, the flow direction of at least a portion of the direct cooling channel of the direct cooling heat exchanger 7 is opposite to the flow direction of at least a portion of the liquid cooling channel of the liquid cooling heat exchanger 1. The temperature of the liquid cooling medium in the downstream section of the liquid cooling channel in the liquid cooling heat exchanger 1 will be higher, and the heat absorption efficiency will be lower. By having the upstream section of the direct cooling channel of the direct cooling heat exchanger 7 correspond to the downstream section of the liquid cooling channel, the heat in the downstream section of the liquid cooling channel can be efficiently absorbed by the direct cooling medium, thereby reducing the temperature of the downstream section of the liquid cooling channel and improving the heat absorption balance between the upstream and downstream sections of the liquid cooling channel.

[0035] Optionally, the direct cooling loop also includes a first fan 9, which is used to increase the airflow velocity at the first condenser 5 to enhance the heat dissipation at the first condenser 5.

[0036] Optionally, such as Figure 2 As shown, in some embodiments, the liquid chiller 2 includes a first heat exchanger 21, with a first side of the first heat exchanger 21 connected to the liquid cooling branch, and a second side of the first heat exchanger 21 connected in parallel with the direct cooling heat exchanger 7. That is, the liquid chiller 2 and the direct cooling loop share some components; part of the cooling medium is used to absorb heat in the direct cooling heat exchanger 7, and part is used to absorb heat in the first heat exchanger 21, thereby reducing the cost and space required for this hybrid thermal management system.

[0037] Optionally, a second regulating valve 13 is also required downstream of the first throttle valve 6. The second regulating valve 13 is used to control the flow rate of the cold medium flowing through the direct cooling heat exchanger 7 and the first heat exchanger 21.

[0038] Optionally, such as Figure 3 As shown, in some other embodiments, the liquid cooler 2 includes an internal circulation loop, which includes a first side of a second heat exchanger 22, a second compressor 23, a second condenser 24, and a second throttle valve 25 connected in sequence. The second side of the second heat exchanger 22 is connected to the liquid cooling branch. The internal circulation loop contains the same or a different type of refrigerant as the direct cooling circulation loop.

[0039] Optionally, the internal circulation loop also includes a second gas-liquid separator 27, which is disposed between the second compressor 23 and the second heat exchanger 22 to protect the second compressor 23.

[0040] Optionally, the liquid cooler 2 also includes a second fan 26, which is used to increase the airflow velocity at the second condenser 24 to enhance heat dissipation at the second condenser 24.

[0041] The control method of this air-cooled, liquid-cooled, and direct-cooled hybrid thermal management system includes the following steps: First, it is necessary to determine whether the difference between the ambient temperature and the outlet temperature of the liquid-cooled heat exchanger 1 is greater than or equal to a preset difference T0. The outlet temperature of the liquid-cooled heat exchanger 1 is measured by the second temperature sensor 14. It is known that the larger the difference, the greater the ambient temperature cooling capacity that can be further absorbed. At this time, the air-cooling mode can be activated to use the ambient temperature cooling capacity to reduce the temperature of the battery 900. Optionally, in this embodiment, the preset difference T0 is 5℃. Of course, in other embodiments, it can also be set to a temperature difference of 3℃, 4℃, 6℃, 7℃, 8℃, 9℃, 10℃, or even greater.

[0042] Specifically, when the difference between the ambient temperature and the outlet temperature of the liquid-cooled heat exchanger 1 is greater than or equal to the preset difference T0, it is necessary to further determine whether the difference A between the maximum cooling capacity of the air-cooled unit and the required cooling capacity is greater than zero. If it is, it means that turning on the air-cooled unit alone can meet the cooling requirements of the battery 900. Otherwise, it means that even if the air-cooled unit is turned on to the maximum, it cannot meet the cooling requirements of the battery 900. In this case, it is necessary to further turn on the liquid cooler 2 so that both the liquid cooler 2 and the air-cooled dry cooler 3 are turned on, that is, to turn on the air-cooled liquid cooling mode.

[0043] Optionally, the maximum cooling capacity and required cooling capacity for air cooling are calculated data. Specifically, they are calculated based on real-time ambient temperature, real-time charge / discharge rate, and a simulation database. Optionally, the simulation database is a database obtained through simulation calculations based on the specifications of the thermal management system of the battery 900.

[0044] Specifically, when the difference A between the maximum cooling capacity of the air-cooled unit and the required cooling capacity is greater than zero, only the air-cooled dry cooler 3 is turned on, that is, the air-cooled mode is turned on, and the speed B of the third fan 31 of the air-cooled dry cooler 3 is adjusted by PID.

[0045] When the difference A between the maximum cooling capacity of the air-cooled unit and the required cooling capacity is less than or equal to zero, the air-cooled dry cooler 3 and the liquid cooler 2 are turned on simultaneously, that is, the air-cooled and liquid-cooled mode is turned on. The wind speed B of the third fan 31 of the air-cooled dry cooler 3 is adjusted to the maximum, and the operating power of the liquid cooler 2 is adjusted by PID control.

[0046] Optionally, dynamic PID control is performed based on the difference between the theoretical supply temperature and the inlet temperature of the liquid-cooled heat exchanger 1. The inlet temperature of the liquid-cooled heat exchanger 1 is measured in real time by the first temperature sensor 12.

[0047] Optionally, the theoretical liquid supply temperature is calculated. Specifically, it is calculated based on the real-time ambient temperature, the real-time charge / discharge rate, and a simulation database. Optionally, the theoretical liquid supply flow rate can also be calculated based on the real-time ambient temperature, the real-time charge / discharge rate, and the simulation database, and the flow rate of the liquid cooling medium in the liquid cooling circulation loop can be adjusted according to this theoretical liquid supply flow rate.

[0048] In air-cooled / liquid-cooled mode, if the liquid cooler 2 operates at full load for a duration of T1, it indicates that the battery 900 may not have been cooled to its ideal state. In this case, it is necessary to further determine whether the inlet temperature of the liquid-cooled heat exchanger 1 is greater than the theoretical supply temperature. That is, further data analysis is needed to determine whether the air-cooled / liquid-cooled mode is still insufficient to meet the cooling requirements of the battery 900. Of course, if the liquid cooler 2 is not operating at full load, or if the liquid cooler 2 operates at full load for a very short time and does not reach T1, it can be considered that the cooling of the battery 900 has reached its ideal state, and the air-cooled / liquid-cooled mode is sufficient to meet the cooling requirements of the battery 900. In this case, no further data analysis is needed, and the air-cooled / liquid-cooled mode can continue to be maintained.

[0049] When the liquid chiller 2 is running at full load for a duration of T1, and the liquid inlet temperature of the liquid-cooled heat exchanger 1 is still greater than the theoretical liquid supply temperature, that is, the required cooling capacity is greater than the sum of the maximum cooling capacities of air cooling and liquid cooling, then the equipment on the direct cooling loop, including the first compressor 4, the first condenser 5, the first throttle valve 6, etc., is turned on, and the system enters the air-cooled liquid-cooled direct cooling mode to further improve the system's heat dissipation capacity.

[0050] In the air-cooled, liquid-cooled, and direct-cooling mode, the PID controller adjusts the operating power of the first compressor 4 and the opening of the first throttle valve 6 so that the direct-cooling heat exchanger 7 can absorb the heat from the liquid-cooling heat exchanger 1, further reducing the temperature of the battery 900.

[0051] When the difference between the ambient temperature and the outlet temperature of the liquid-cooled heat exchanger 1 is less than the preset difference T0, it indicates that the amount of ambient cold that can be further absorbed is very small, and the air-cooled mode is not applicable. Therefore, the air-cooled dry cooler 3 is turned off, and the liquid cooler 2 is turned on, i.e., the system enters the liquid-cooled mode. Similarly, the operating power of the liquid cooler 2 is adjusted by PID control to minimize energy consumption while meeting the heat dissipation requirements of the 900 battery.

[0052] In liquid cooling mode, if liquid cooler 2 operates at full load for a duration of T2, it indicates that battery 900 may not have been cooled to its ideal state. In this case, it is necessary to further determine whether the inlet temperature of liquid cooling heat exchanger 1 is greater than the theoretical supply temperature, i.e., to further determine through data whether liquid cooling mode still cannot meet the heat dissipation requirements of battery 900. Of course, if liquid cooler 2 does not operate at full load, or if liquid cooler 2 operates at full load for a very short time and does not reach T2, it can be considered that the heat dissipation of battery 900 has reached the ideal state, and liquid cooling mode is sufficient to meet the heat dissipation requirements of battery 900. In this case, no further data judgment is needed, and liquid cooling mode can continue to be maintained.

[0053] When the liquid chiller 2 runs at full load for a period of time T2, and the liquid inlet temperature of the liquid-cooled heat exchanger 1 is still greater than the theoretical liquid supply temperature, that is, the required cooling capacity is greater than the maximum cooling capacity of the liquid chiller 2, then the equipment on the direct cooling loop, including the first compressor 4, the first condenser 5, the first throttle valve 6, etc., are turned on, and the system enters the liquid-cooled direct cooling mode to further improve the heat dissipation capacity of the system.

[0054] In the liquid-cooled direct-cooling mode, the PID controller adjusts the operating power of the first compressor 4 and the opening of the first throttle valve 6 so that the direct-cooling heat exchanger 7 can absorb the heat from the liquid-cooled heat exchanger 1, meeting the heat dissipation requirements of the battery 900 while minimizing the energy consumption of the equipment in the liquid-cooled circulation loop and the direct-cooling circulation loop.

[0055] It is known that the hybrid thermal management system can realize five modes: air-cooled mode, air-cooled liquid-cooled mode, air-cooled liquid-cooled direct cooling mode, liquid-cooled mode, and liquid-cooled direct cooling mode. It can determine the most suitable operating mode under different ambient temperatures and operating conditions. With dynamic PID adjustment, it can meet the heat dissipation requirements of the battery 900 and ensure that the battery 900 achieves the best operating state. At the same time, the hybrid thermal management system can also maximize the utilization of ambient temperature cooling capacity, minimize energy consumption, and improve energy efficiency by adopting the above control method.

[0056] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A hybrid thermal management system characterized by, It includes a liquid-cooled circulation loop containing a liquid cooling medium. The liquid-cooled circulation loop includes a first pipe and a second pipe that are connected in a circulation. A liquid-cooled heat exchanger (1) is provided on the first pipe. The liquid-cooled heat exchanger (1) is used to absorb the heat of the battery (900). The second pipe includes a liquid-cooled branch and an air-cooled branch connected in series or in parallel. A liquid-cooled chiller (2) is provided on the liquid-cooled branch, and an air-cooled dry cooler (3) is provided on the air-cooled branch.

2. The hybrid thermal management system of claim 1, wherein, It also includes a direct cooling circulation loop, which contains a cooling medium. The direct cooling circulation loop includes a first compressor (4), a first condenser (5), a first throttle valve (6), and a direct cooling heat exchanger (7) connected in sequence. The direct cooling heat exchanger (7) is used to absorb the heat from the liquid cooling heat exchanger (1).

3. The hybrid thermal management system of claim 2, wherein, The direct cooling circulation loop also includes a first gas-liquid separator (8), which is disposed between the first compressor (4) and the direct cooling heat exchanger (7).

4. The hybrid thermal management system of claim 2, wherein, The flow direction of at least a portion of the direct cooling flow channel of the direct cooling heat exchanger (7) is opposite to the flow direction of at least a portion of the liquid cooling flow channel of the liquid cooling heat exchanger (1).

5. The hybrid thermal management system according to claim 2, characterized in that, The direct cooling loop also includes a first fan (9), which is used to increase the airflow speed at the first condenser (5).

6. The hybrid thermal management system of any of claims 2-5, wherein, The liquid cooler (2) includes a first heat exchanger (21), the first side of which is connected to the liquid cooling branch, and the second side of which is connected in parallel with the direct cooling heat exchanger (7).

7. The hybrid thermal management system of any of claims 1-5, wherein, The liquid cooler (2) includes an internal circulation loop, which includes a first side of a second heat exchanger (22), a second compressor (23), a second condenser (24), and a second throttle valve (25) connected in sequence. The second side of the second heat exchanger (22) is connected to the liquid cooling branch.

8. The hybrid thermal management system of claim 7, wherein, The liquid chiller (2) also includes a second fan (26) for increasing the airflow velocity at the second condenser (24).

9. The hybrid thermal management system of any of claims 1-5, wherein, The liquid cooling circulation loop also includes a first regulating valve (10). The liquid cooling branch and the air cooling branch are connected in parallel. The first regulating valve (10) is used to regulate the flow rate of the liquid cooling medium in the liquid cooling branch and the air cooling branch.

10. The hybrid thermal management system of any of claims 1-5, wherein, The liquid cooling circulation loop also includes a circulation pump (11), which is installed on the first pipeline.

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