Thermal management system and method of controlling the same, energy storage container

Abstract

This application provides a thermal management system and its control method, and an energy storage container, comprising: a refrigerant circuit having a compressor, a first heat exchanger, a second heat exchanger, and a third heat exchanger; the third heat exchanger having a first heat exchange section and a second heat exchange section that exchanges heat with the first heat exchange section; the compressor outlet being connected to the first heat exchange section via the first or second heat exchanger; and the compressor inlet being connected to the second heat exchange section, so as to exchange heat and raise the temperature of the refrigerant flowing to the compressor inlet through the third heat exchanger; and a temperature control component for sensing the amount of heat exchange between the first and second heat exchange sections, and adjusting at least one of the second heat exchanger, the third heat exchanger, and the compressor based on the amount of heat exchange. Thus, by setting the temperature control component, the amount of heat exchange in the third heat exchanger can be controlled, ensuring that only a two-phase state of constant-temperature evaporation exists in the first or second heat exchanger, thereby guaranteeing the uniform temperature of multiple cells within the battery.

Description

Technical Field

[0001] This application relates to the field of energy storage system technology, specifically to a thermal management system and its control method, and an energy storage container. Background Technology

[0002] Energy storage technology can alter the real-time characteristics of power transmission, making electricity use more flexible. It is a strategic supporting technology for energy structure transformation and changes in electricity production and consumption patterns. With the increasing demand for energy storage, temperature control of energy storage systems is a crucial aspect of ensuring their normal operation.

[0003] In the process of realizing this invention, the inventors discovered at least the following technical problems in the prior art: In existing technologies, temperature control of energy storage batteries generally employs direct cooling, using a refrigerant as the heat transfer medium. Heat exchange between the energy storage battery and the refrigerant is achieved through the flow and phase change of the refrigerant. The uniformity of cell temperature within the energy storage battery is a core indicator, and handling overheating is particularly important, especially regarding the heat exchange state of the refrigerant within the cell's cooling plate. However, existing direct cooling methods suffer from poor internal temperature uniformity in the heat exchangers that exchange heat between multiple batteries in the energy storage system, thus affecting the stable operation of the energy storage battery. Summary of the Invention

[0004] In view of this, this application provides a thermal management system and its control method, and an energy storage container, which can at least improve the problem of poor internal temperature uniformity of the heat exchanger that exchanges heat with multiple batteries in the energy storage system.

[0005] To achieve the above objectives, this application provides the following technical solution: A thermal management system for heat exchange of multiple batteries in an energy storage system, comprising: A refrigerant circuit includes a compressor, a first heat exchanger, a second heat exchanger, and a third heat exchanger. The third heat exchanger has a first heat exchange section and a second heat exchange section that exchanges heat with the first heat exchange section. The outlet of the compressor is connected to the first heat exchange section through the first heat exchanger or the second heat exchanger, and the inlet of the compressor is connected to the second heat exchange section, so that the refrigerant flowing to the inlet of the compressor is heated by exchanging heat with the third heat exchanger. A temperature control component is used to sense the amount of heat exchanged between the first heat exchange section and the second heat exchange section, so as to adjust at least one of the second heat exchanger, the third heat exchanger and the compressor according to the amount of heat exchanged.

[0006] Optionally, the temperature control component includes: A first temperature sensor is installed at the outlet of the second heat exchange section to sense the temperature of the refrigerant flowing to the compressor inlet; The second and third temperature sensors are respectively installed at the inlet and outlet of the first heat exchange section.

[0007] Optionally, the temperature control component includes a control module, wherein the second temperature sensor, the third temperature sensor, the first temperature sensor, and the second heat exchanger are all communicatively connected to the control module to adjust the second heat exchanger according to the amount of heat exchange.

[0008] Optionally, the second heat exchanger has a heat exchanger body and a fan, and the control module is communicatively connected to the fan to adjust the fan speed.

[0009] Optionally, the compressor inlet is provided with a gas-liquid separator to separate the refrigerant passing through the first temperature sensor into gas and liquid components.

[0010] Optionally, a pressure sensor is provided between the gas-liquid separator and the first temperature sensor.

[0011] Optionally, the compressor outlet is provided with a fourth temperature sensor that is communicatively connected to the control module.

[0012] Optionally, the inlet of the first heat exchange section is provided with a liquid reservoir, and the second temperature sensor is located between the liquid reservoir and the first heat exchange section; the outlet of the first heat exchange section is provided with a dryer, and the third temperature sensor is located between the dryer and the first heat exchange section.

[0013] Optionally, a multi-port valve is included, the multi-port valve having a first port, a second port, a third port and a fourth port, wherein different ports of the first port, the second port, the third port and the fourth port are connected in pairs in different modes; The first interface is connected to the outlet of the compressor, the second interface is connected to the first end of the first heat exchanger, the second end of the first heat exchanger is connected to the first end of the second heat exchanger through the first heat exchange section, the second end of the second heat exchanger is connected to the third interface, and the fourth interface is connected to the inlet of the compressor through the second heat exchange section.

[0014] An energy storage container includes a thermal management system as described in any of the preceding claims.

[0015] The thermal management system and control method, and energy storage container provided in this application, include a temperature control component used to sense the amount of heat exchanged between the first and second heat exchange sections. This allows for automatic or manual adjustment of at least one of the second heat exchanger, the third heat exchanger, and the compressor based on the amount of heat exchanged. In application, the temperature control component can adjust the compressor's return gas superheat to 5K. For example, it can adjust the compressor's power or change the compressor model to set the return gas superheat to a preset fixed value. For the third heat exchanger, the heat exchange involves the subcooled liquid on the condenser side and the gas on the evaporator side. The temperature control component can adjust the temperature difference ratio between these two components. For example, a minimum temperature difference ratio of 1:1.3 is used, meaning that if the high-pressure side liquid cools by 1K, the low-pressure side pure gas must heat up by at least 1.3K. Under the condition that the outlet of the second heat exchange section (i.e. the compressor return port) is overheated by 5K, the temperature difference before and after the first heat exchange section can be adjusted to at least 5K by the temperature control component. Since the mass flow rates of the first and second heat exchange sections are the same, the inlet of the second heat exchange section will definitely be wet steam with a dryness fraction of less than 1. That is, the outlet of the first heat exchanger or the second heat exchanger (here, the first heat exchanger is used as an example) before the second heat exchange section is wet steam. Therefore, there is only a two-phase evaporation process inside the first heat exchanger, without overheating, which can ensure the uniform temperature of the first heat exchanger and at the same time ensure the uniform temperature of multiple cells in the battery. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a thermal management system in cooling mode, as shown in some embodiments.

[0018] Figure 2 This is a schematic diagram of a thermal management system in heating mode, as shown in some embodiments.

[0019] In the diagram: 1. Compressor; 2. Multi-way valve; 3. First heat exchanger; 4. Third heat exchanger; 5. Second heat exchanger; 6. Liquid receiver; 7. Dryer; 8. Oil separator; 9. Oil return capillary tube; 10. Gas-liquid separator; 11. First temperature sensor; 12. Second temperature sensor; 13. Third temperature sensor; 14. Fourth temperature sensor; 15. Pressure sensor; 16. First check valve; 17. Second check valve; 18. Heating expansion valve; 19. Cooling expansion valve. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] like Figures 1-2 As shown, this application embodiment provides a thermal management system for heat exchange of a battery (which can be used for photovoltaic energy storage, or for all electrical energy fields such as wind, solar, hydro, thermal, geothermal, tidal, nuclear, biomass, and power grids) to maintain the battery temperature within a reasonable range. This system can be used for both heating and cooling the battery. The thermal management system includes a refrigerant circuit through which refrigerant flows. The refrigerant's flow and phase change within the circuit allow for heating and cooling at various component locations within the circuit.

[0022] The refrigerant circuit includes a compressor 1, a first heat exchanger 3, a second heat exchanger 5, and a third heat exchanger 4. The first heat exchanger 3 directly exchanges heat with the battery; for example, it can be configured as a heat exchange plate, where the refrigerant flows and undergoes phase change to remove heat or cold from the battery. The second heat exchanger 5 is located in the external environment outside the battery and functions as an evaporator for heat absorption or a condenser for heat release. The third heat exchanger 4 has a first heat exchange section and a second heat exchange section. Heat exchange can occur through these two sections; for example, the first and second heat exchange sections can be configured as two adjacent heat exchange pipes within the third heat exchanger 4.

[0023] The outlet of compressor 1 is connected to the first heat exchange section via either the first heat exchanger 3 or the second heat exchanger 5. The connection method differs depending on the operating mode. For example, in the first operating mode, the first heat exchanger 3 connects the outlet of compressor 1 and the first heat exchange section; in the second operating mode, the second heat exchanger 5 connects the outlet of compressor 1 and the first heat exchange section. The inlet of compressor 1 is connected to the second heat exchange section so that the refrigerant must first flow through the second heat exchange section before flowing to the inlet of compressor 1. During operation, the high-temperature and high-pressure gaseous refrigerant flowing out of the compressor 1 passes through the second heat exchanger 5 / first heat exchanger 3 and then flows through the first heat exchange section of the third heat exchanger 4 for heat exchange and cooling. At the same time, the refrigerant flowing out of the first heat exchanger 3 / second heat exchanger 5 flows through the second heat exchange section for heat exchange and heating. This allows the refrigerant flowing into the second heat exchange section to be wet vapor with a dryness fraction of less than 1. The entire overheating process takes place within the second heat exchange section. This ensures that during refrigeration, only a two-phase state of constant-temperature evaporation exists in the first heat exchanger 3 or the second heat exchanger 5, guaranteeing the uniform temperature of multiple cells within the battery.

[0024] The thermal management system includes a temperature control component, which senses the amount of heat exchanged between the first heat exchanger and the second heat exchanger, and then adjusts at least one of the second heat exchanger 5, the third heat exchanger 4, and the compressor 1 based on the amount of heat exchanged. Specifically, the temperature control component can be communicatively connected to at least one of the second heat exchanger 5, the third heat exchanger 4, and the compressor 1 for automatic control; alternatively, operators can adjust the system manually based on the detected amount of heat exchanged.

[0025] During application, the superheat of compressor 1 in the return gas state can be adjusted to 5K using the temperature control component. For example, the temperature control component can adjust the power of compressor 1 or change the model of compressor 1 to set the superheat of compressor 1 in the return gas state to a preset fixed value. For the third heat exchanger 4, heat is exchanged between the subcooled liquid on the condensing side and the gas on the evaporating side. The temperature control component can adjust the temperature difference ratio between the two, with the limit being at least 1:1.3. Taking this as an example, if the liquid on the high-pressure side cools down by 1K, the pure gas on the low-pressure side will heat up by at least 1.3K. Under the condition that the outlet of the second heat exchange section (i.e. the return gas port of compressor 1) is overheated by 5K, the temperature difference before and after the first heat exchange section can be adjusted to at least 5K by the temperature control component. Since the mass flow rates of the first and second heat exchange sections are the same, the inlet of the second heat exchange section will definitely be wet steam with a dryness fraction of less than 1. That is, the outlet of the first heat exchanger 3 or the second heat exchanger 5 (here, the first heat exchanger 3 is used as an example) in front of the second heat exchange section is wet steam. Therefore, there is only a two-phase evaporation process inside the first heat exchanger 3, without overheating, which can ensure the uniform temperature of the first heat exchanger 3 and at the same time ensure the uniform temperature of multiple cells in the battery.

[0026] In this solution, the thermal management system also includes a multi-way valve 2, which has a first interface a, a second interface b, a third interface c, and a fourth interface d. For example, the multi-way valve 2 can be configured as a four-way valve, or it can be configured as a five-way valve or a six-way valve. In different modes, different interfaces among the first, second, third, and fourth interfaces are connected in pairs to switch the operating mode of the thermal management system via the multi-way valve 2. Specifically, the first interface is connected to the outlet of the compressor 1, the second interface is connected to the first end of the first heat exchanger 3, the second end of the first heat exchanger 3 is connected to the first end of the second heat exchanger 5 through the first heat exchange section, the second end of the second heat exchanger 5 is connected to the third interface, and the fourth interface is connected to the inlet of the compressor 1 through the second heat exchange section.

[0027] like Figure 1As shown, in cooling mode, the first port of multi-way valve 2 is connected to the third port, and the second port is connected to the fourth port. Compressor 1 compresses low-pressure gaseous refrigerant into high-temperature, high-pressure gaseous refrigerant. The high-temperature, high-pressure gaseous refrigerant flowing out of the outlet of compressor 1 flows to the second heat exchanger 5. The room-temperature liquid refrigerant condensed in the second heat exchanger 5 first flows through the first heat exchange section, and then through the first heat exchanger 3. The refrigerant evaporated in the first heat exchanger 3 first flows through the second heat exchange section, and then flows back to the inlet of compressor 1. Since the temperature of the refrigerant in the first heat exchange section is higher than that in the second heat exchange section, the refrigerant flowing out of the second heat exchanger 5 can exchange heat with the refrigerant flowing out of the first heat exchanger 3 through the third heat exchanger 4, thereby heating the refrigerant flowing to the inlet of compressor 1. This makes the refrigerant flowing into the second heat exchange section a wet vapor with a dryness fraction of less than 1. The entire superheating process takes place in the second heat exchange section, thus ensuring that only a constant-temperature evaporating two-phase state exists in the first heat exchanger during cooling, guaranteeing the uniform temperature of multiple cells in the battery.

[0028] like Figure 2 As shown, in heating mode, the first port of the multi-way valve 2 is connected to the second port, and the third port is connected to the fourth port. Compressor 1 compresses low-pressure gaseous refrigerant into high-temperature, high-pressure gaseous refrigerant. The high-temperature, high-pressure gaseous refrigerant flowing out of the outlet of compressor 1 flows to the first heat exchanger 3. The room-temperature liquid refrigerant condensed in the first heat exchanger 3 first flows through the first heat exchange section, and then flows through the second heat exchanger 5. The refrigerant evaporated in the second heat exchanger 5 first flows through the second heat exchange section, and then flows back to the inlet of compressor 1. Since the temperature of the refrigerant in the first heat exchange section is higher than that in the second heat exchange section, the refrigerant flowing out of the first heat exchanger 3 can exchange heat with the refrigerant flowing out of the second heat exchanger 5 through the third heat exchanger 4, thereby heating the refrigerant flowing to the inlet of compressor 1. This allows the refrigerant flowing into the second heat exchange section to be wet vapor with a dryness fraction of less than 1. The entire superheating process takes place in the second heat exchange section, thus ensuring that only a constant-temperature evaporating two-phase state exists in the second heat exchanger during heating, which is beneficial for ensuring the uniform temperature of multiple cells in the battery.

[0029] It should be noted that the first end and the second end of the first heat exchanger 3 are two ports. In the first operating mode, the refrigerant flows into the first end of the first heat exchanger 3 and flows out through the second end. In the second operating mode, the refrigerant flows into the second end of the first heat exchanger 3 and flows out through the first end. That is, one of the first end and the second end is the inlet of the first heat exchanger 3, and the other is the outlet of the first heat exchanger 3. Correspondingly, the first end and the second end of the second heat exchanger 5 are two ports. In the first operating mode, the refrigerant flows into the first end of the second heat exchanger 5 and flows out through the second end. In the other operating mode, the refrigerant flows into the second end of the second heat exchanger 5 and flows out through the first end. That is, one of the first end and the second end is the inlet of the second heat exchanger 5, and the other is the outlet of the second heat exchanger 5.

[0030] In some embodiments, the temperature control assembly includes a first temperature sensor 11, a second temperature sensor 12, and a third temperature sensor 13. The first temperature sensor 11 is located between the outlet of the second heat exchanger and the inlet of the compressor 1, and is used to sense the temperature of the refrigerant flowing towards the inlet of the compressor 1. The second temperature sensor 12 is located at the inlet of the first heat exchanger and is used to detect the temperature of the refrigerant flowing into the first heat exchanger from the inlet. The third temperature sensor 13 is located at the outlet of the first heat exchanger and is used to detect the temperature of the refrigerant flowing out of the outlet of the first heat exchanger. Thus, the temperature difference between the inlet and outlet of the first heat exchanger can be calculated based on the sensing values ​​of the second temperature sensor 12 and the third temperature sensor 13. Given a fixed heat exchange ratio of the third heat exchanger 4, the heat exchange capacity of the third heat exchanger 4 can be obtained, along with the temperature difference between the inlet and outlet of the second heat exchanger. By adjusting the power of the compressor 1, the fan speed of the second heat exchanger 5, and other controllable components in the refrigerant circuit based on the values ​​measured by multiple temperature sensors, the temperature of the refrigerant flowing back to the compressor 1 can be maintained within a suitable range, which improves the timeliness of regulation.

[0031] In the preferred embodiment, the temperature control component also includes a control module to facilitate automated system control and save labor costs. The first temperature sensor 11, the second temperature sensor 12, the third temperature sensor 13, and the second heat exchanger 5 are all communicatively connected to the control module. The control module can regulate the second heat exchanger 5 based on the heat exchange capacity of the third heat exchanger 4, ensuring that the refrigerant flowing into the second heat exchange section is wet vapor with a dryness fraction of less than 1. The entire superheating process occurs within the second heat exchange section, thereby achieving a two-phase state of constant-temperature evaporation in the first heat exchanger during cooling, ensuring uniform temperature across the multiple battery cells.

[0032] The second heat exchanger 5 includes a heat exchanger body and a fan. The fan rotates, driving airflow through the heat exchanger body to accelerate heat exchange. A control module is communicatively connected to the fan and used to adjust the fan speed. When the temperature difference between the inlet and outlet of the first heat exchanger is less than a preset value, the control module controls the fan speed to decrease, thereby increasing the inlet temperature of the first heat exchanger. When the temperature difference between the inlet and outlet of the first heat exchanger is greater than the preset value, the control module controls the fan speed to increase, thereby decreasing the inlet temperature of the first heat exchanger.

[0033] Of course, in other solutions, the control module can communicate with the compressor 1 and control the operating power of the compressor 1 to increase or decrease the heat exchange capacity of the third heat exchanger 4, thereby adjusting the inlet and outlet temperature difference of the first and second heat exchange sections.

[0034] In some preferred embodiments, a gas-liquid separator 10 is provided between the inlet of compressor 1 and the first temperature sensor 11 to separate the refrigerant into gas and liquid states as it passes through the first temperature sensor 11 and flows to the inlet of compressor 1. The gas-liquid separator 10 separates liquid refrigerant, ensuring that the refrigerant flowing into the inlet of compressor 1 is gaseous, thus improving system safety and stability.

[0035] A pressure sensor 15 is installed between the gas-liquid separator 10 and the first temperature sensor 11, so that the refrigerant flowing out of the second heat exchange section passes sequentially through the first temperature sensor 11, the pressure sensor 15, and the gas-liquid separator. The pressure sensor 15 can detect the pressure of the refrigerant flowing back to the compressor 1 inlet and communicate with the control module. Based on the value measured by the pressure sensor 15, the power of the compressor 1, the fan speed of the second heat exchanger 5, and other controllable components in the refrigerant circuit can be adjusted, further improving the stability and controllability of the system.

[0036] A fourth temperature sensor 14 is installed at the outlet of compressor 1 so that the refrigerant flowing out of the outlet of compressor 1 first passes through the fourth temperature sensor 14 before flowing to the first port of multi-way valve 2. The fourth temperature sensor 14 is communicatively connected to the control module and is used to detect the temperature of the refrigerant flowing out of the outlet of compressor 1. Based on the value measured by the fourth temperature sensor 14, the power of compressor 1, the fan speed of the second heat exchanger 5, and other controllable components in the refrigerant circuit can be adjusted to further improve the stability and controllability of the system.

[0037] In some embodiments, the refrigerant circuit includes a reversing structure disposed between the second end of the first heat exchanger 3, the first end of the second heat exchanger 5, and the first heat exchange section. Through the reversing action of the reversing structure, the refrigerant flow direction in the first heat exchange section can be opposite to that in the second heat exchange section under different modes, thereby improving the heat exchange efficiency of the third heat exchanger 4.

[0038] The reversing structure includes a first branch, a second branch, a third branch, and a fourth branch. The first branch connects the second end of the first heat exchanger 3 to the inlet of the first heat exchange section. The second branch connects the first end of the second heat exchanger 5 to the outlet of the first heat exchange section. The third branch connects the first end of the second heat exchanger 5 to a first position on the first branch. The fourth branch connects the second end of the first heat exchanger 3 to a second position on the second branch. A first one-way valve 16 is installed on the first branch, located between the second end of the first heat exchanger 3 and the first position, to unilaterally prevent refrigerant from flowing from the first position to the first heat exchanger 3. A second one-way valve 17 is installed on the third branch, located between the first ends of the second heat exchanger 5, to unilaterally prevent refrigerant from flowing from the first position to the second heat exchanger 5.

[0039] A heating expansion valve 18 is installed on the second branch, located between the second heat exchanger 5 and the second position. A cooling expansion valve 19 is installed on the fourth branch, located between the second end and the second position of the first heat exchanger 3. In heating mode, the heating expansion valve 18 is open and the cooling expansion valve 19 is closed. The refrigerant flowing from the second end of the first heat exchanger 3 first flows through the first branch to the inlet of the first heat exchange section of the third heat exchanger 4, and then flows through the second branch to the first end of the second heat exchanger 5. In cooling mode, the cooling expansion valve 19 is open and the heating expansion valve 18 is closed. The refrigerant flowing from the first end of the second heat exchanger 5 first flows through the third branch to the first position of the first branch, and then flows through the first branch to the inlet of the first heat exchange section of the third heat exchanger 4. The refrigerant flowing from the outlet of the first heat exchange section first flows through the second branch to the second position, and then flows through the fourth branch to the second end of the first heat exchanger 3. Thus, by switching the reversing structure, the refrigerant flows into the first heat exchange section from the first branch and then flows out of the first heat exchange section from the second branch in different modes, thereby making the refrigerant flow direction in the first heat exchange section opposite to that in the second heat exchange section, thereby improving the heat exchange efficiency of the third heat exchanger 4.

[0040] It should be noted that, in different modes, the inlet of the first heat exchanger is connected to the first branch, the outlet of the first heat exchanger is connected to the second branch, the inlet of the second heat exchanger is connected to the fourth port of the multi-way valve 2, and the outlet of the second heat exchanger is connected to the inlet of the compressor 1. Furthermore, the aforementioned refrigeration expansion valve 19 and heating expansion valve 18 constitute the throttling components in this system to achieve stable system operation.

[0041] In some preferred embodiments, the inlet of the first heat exchange section is equipped with a liquid receiver 6. For example, the liquid receiver 6 is located on the first branch and between the first position and the second temperature sensor 12. The liquid receiver can store refrigerant, separate gaseous and liquid refrigerant, and buffer pressure in the refrigerant circuit. The outlet of the first heat exchange section is equipped with a dryer 7. The dryer 7 is located on the second branch and between the third temperature sensor 13 and the second position. The dryer 7 can absorb moisture in the refrigerant and filter impurities in the refrigerant in the refrigerant circuit.

[0042] This application provides a control method for a thermal management system, based on the thermal management system described in the above embodiments, including: The sensing values ​​of the first temperature sensor and the second temperature sensor are obtained, and the inlet and outlet temperature difference of the first heat exchange section is calculated. Obtain the sensing value of the third temperature sensor and calculate the inlet temperature of the second heat exchanger; Determine whether the inlet temperature of the second heat exchange section is greater than the preset value; If so, then the fan speed of the second heat exchanger is reduced, or the power of the compressor is increased, or the heat exchange ratio of the third heat exchanger is increased.

[0043] The heat transfer ratio of the third heat exchanger can be set to a fixed value. Based on the calculated inlet and outlet temperature difference of the first heat exchange section and the sensed outlet temperature of the second heat exchange section, the inlet temperature of the second heat exchange section, which is the outlet temperature of the first heat exchanger, can be further calculated. This allows for the regulation of the outlet temperature of the first heat exchanger. When the inlet temperature of the second heat exchange section exceeds the preset value, the second heat exchanger, the compressor, and the third heat exchanger can be regulated. For example, the fan speed of the second heat exchanger can be controlled, or the power of the compressor can be controlled, or the heat transfer ratio of the third heat exchanger can be adjusted.

[0044] During application, the superheat of compressor 1 in the return gas state can be adjusted to 5K using the temperature control component. For example, the temperature control component can adjust the power of compressor 1 or change the model of compressor 1 to set the superheat of compressor 1 in the return gas state to a preset fixed value. For the third heat exchanger 4, heat is exchanged between the subcooled liquid on the condensing side and the gas on the evaporating side. The temperature control component can adjust the temperature difference ratio between the two, with the limit being at least 1:1.3. Taking this as an example, if the liquid on the high-pressure side cools down by 1K, the pure gas on the low-pressure side will heat up by at least 1.3K. Under the condition that the outlet of the second heat exchange section (i.e. the return gas port of compressor 1) is overheated by 5K, the temperature difference before and after the first heat exchange section can be adjusted to at least 5K by the temperature control component. Since the mass flow rates of the first and second heat exchange sections are the same, the inlet of the second heat exchange section will definitely be wet steam with a dryness fraction of less than 1. That is, the outlet of the first heat exchanger 3 or the second heat exchanger 5 (taking the first heat exchanger 1 as an example) in front of the second heat exchange section is wet steam. Therefore, there is only a two-phase evaporation process inside the first heat exchanger 3, without overheating, which can ensure the uniform temperature of the first heat exchanger 3, and at the same time ensure the uniform temperature of multiple cells in the energy storage battery.

[0045] This application provides an energy storage container, including the thermal management system described in the above embodiment. Thus, through the regulation of the temperature control components, the temperature of the refrigerant flowing back to the compressor 1 can be maintained within a reasonable range.

[0046] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.

[0047] The block diagrams of devices, apparatuses, devices, and systems involved in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0048] It should also be noted that in the apparatus, equipment, and methods of this application, the components or steps can be disassembled and / or recombined. These disassemblies and / or recombinations should be considered as equivalent solutions of this application.

[0049] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this application. Therefore, this application is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0050] It should be understood that the qualifying terms “first,” “second,” “third,” “fourth,” “fifth,” and “sixth” used in the description of the embodiments of this application are only used to more clearly illustrate the technical solutions and are not intended to limit the scope of protection of this application.

[0051] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A thermal management system, characterized in that, Used for heat exchange of multiple batteries in an energy storage system, including: A refrigerant circuit includes a compressor, a first heat exchanger, a second heat exchanger, and a third heat exchanger. The third heat exchanger has a first heat exchange section and a second heat exchange section that exchanges heat with the first heat exchange section. The outlet of the compressor is connected to the first heat exchange section through the first heat exchanger or the second heat exchanger, and the inlet of the compressor is connected to the second heat exchange section, so that the refrigerant flowing to the inlet of the compressor is heated by exchanging heat with the third heat exchanger. A temperature control component includes a first temperature sensor, a second temperature sensor, and a third temperature sensor. The first temperature sensor is disposed between the outlet of the second heat exchange section and the inlet of the compressor to sense the temperature of the refrigerant flowing towards the compressor inlet. The second temperature sensor is disposed at the inlet of the first heat exchange section to detect the temperature of the refrigerant flowing into the first heat exchange section from the inlet. The third temperature sensor is disposed at the outlet of the first heat exchange section to detect the temperature of the refrigerant flowing out of the first heat exchange section from the outlet. The temperature control component calculates the temperature difference between the inlet and outlet of the first heat exchange section based on the sensed values ​​of the second and third temperature sensors. Given a fixed heat exchange ratio of the third heat exchanger, the component obtains the heat exchange capacity of the third heat exchanger and simultaneously obtains the temperature difference between the inlet and outlet of the second heat exchange section. The temperature control component calculates the inlet temperature of the second heat exchange section based on the calculated inlet and outlet temperature difference of the first heat exchange section and the sensed outlet temperature of the second heat exchange section. When the inlet temperature of the second heat exchange section is greater than a preset value, the component controls the fan speed of the second heat exchanger, or controls the power of the compressor, or controls the heat exchange ratio of the third heat exchanger.

2. The thermal management system according to claim 1, characterized in that, The temperature control component includes a control module, and the second temperature sensor, the third temperature sensor, the first temperature sensor, and the second heat exchanger are all communicatively connected to the control module.

3. The thermal management system according to claim 2, characterized in that, The second heat exchanger has a heat exchanger body and a fan. The control module is communicatively connected to the fan to adjust the fan speed.

4. The thermal management system according to claim 1, characterized in that, The compressor inlet is equipped with a gas-liquid separator to separate the refrigerant from the refrigerant as it passes through the first temperature sensor.

5. The thermal management system according to claim 4, characterized in that, A pressure sensor is installed between the gas-liquid separator and the first temperature sensor.

6. The thermal management system according to claim 3, characterized in that, The compressor outlet is equipped with a fourth temperature sensor that is communicatively connected to the control module.

7. The thermal management system according to claim 1, characterized in that, The inlet of the first heat exchange section is provided with a liquid reservoir, and the second temperature sensor is located between the liquid reservoir and the first heat exchange section; the outlet of the first heat exchange section is provided with a dryer, and the third temperature sensor is located between the dryer and the first heat exchange section.

8. The thermal management system according to claim 1, characterized in that, The system includes a multi-port valve having a first port, a second port, a third port, and a fourth port, wherein different ports among the first port, the second port, the third port, and the fourth port are connected in pairs in different modes. The first interface is connected to the outlet of the compressor, the second interface is connected to the first end of the first heat exchanger, the second end of the first heat exchanger is connected to the first end of the second heat exchanger through the first heat exchange section, the second end of the second heat exchanger is connected to the third interface, and the fourth interface is connected to the inlet of the compressor through the second heat exchange section.

9. An energy storage container, characterized in that, It includes the thermal management system as described in any one of claims 1-8.

10. A control method for a thermal management system, based on the thermal management system according to any one of claims 1-8, comprising: The sensing values ​​of the first temperature sensor and the second temperature sensor are obtained, and the inlet and outlet temperature difference of the first heat exchange section is calculated. Obtain the sensing value of the third temperature sensor and calculate the inlet temperature of the second heat exchanger; Determine whether the inlet temperature of the second heat exchange section is greater than a preset value; If so, then the fan speed of the second heat exchanger is reduced, or the power of the compressor is increased, or the heat exchange ratio of the third heat exchanger is increased.

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