Rail transit liquid cooling type energy storage thermal management unit

Abstract

The utility model discloses a kind of liquid-cooled energy storage thermal management unit for rail transit, including cabinet, liquid cooling circulation loop, refrigerant circulation loop, cooling liquid inlet pipe, cooling liquid outlet pipe and electric control assembly;Cabinet is divided into condensing cabin, liquid cooling medium distribution cabin and electrical control cabin according to function inside, each cabin is thermally isolated by airtight partition;Liquid cooling circulation loop is arranged in liquid cooling medium distribution cabin, including first PTC electric heater, circulating pump, second PTC electric heater, electric three-way valve and radiator;Refrigerant circulation loop is arranged in condensing cabin, including compressor, condenser, filter and gas-liquid separator;Liquid cooling circulation loop and refrigerant circulation loop are formed heat coupling by plate heat exchanger.The unit structure is compact, and thermal management efficiency is high, through the collaborative work of two circulation loops, the temperature control demand of rail transit energy storage system under different working conditions can be effectively met, improve system stability and security.

Description

Technical Field

[0001] This utility model relates to the field of rail transit equipment, specifically to a liquid-cooled energy storage thermal management unit for rail transit. Background Technology

[0002] With the rapid development of the rail transit industry, energy storage systems, as an important component of rail transit vehicles, are also undergoing continuous development and improvement in their thermal management technology. Thermal management of energy storage systems is crucial for ensuring their safety, reliability, and service life. Currently, thermal management systems for rail transit energy storage primarily employ liquid cooling, using a liquid-cooled circulation loop to remove the heat generated by the energy storage system, thus maintaining its operation within a suitable temperature range.

[0003] In the prior art, CN115692927A discloses a thermal management system and method for a liquid-cooled energy storage unit. This system includes a first liquid-cooled circulation loop, a second liquid-cooled circulation loop, a refrigerant circulation loop, and an evaporative temperature control device. The evaporative temperature control device adjusts the heat exchange between the refrigerant circulation loop and the first and second heat exchange units, so that the coolant temperature of the first liquid-cooled circulation loop differs from that of the second liquid-cooled circulation loop. This system can meet the different operating temperature requirements of the battery system and electrical equipment, improving the overall energy efficiency ratio.

[0004] CN116345018B discloses a battery thermal management system, including a compressor, a liquid-cooled condenser, a liquid storage tank, a throttling device, and a battery heat exchanger connected in sequence to form a loop, as well as a radiator, an electric heater, and multiple valves. Different operating modes are achieved by controlling the on / off states of different valves. This system is suitable for battery thermal management needs under extremely cold conditions.

[0005] CN115621616B discloses a thermal management unit for an energy storage power station, including a frame and at least two sets of thermal management units. Each thermal management unit includes a refrigerant circulation loop consisting of a compressor, a liquid-cooled condenser, a throttling device, and a battery heat exchanger, as well as a coolant circulation loop controlled by a four-way valve. This thermal management unit adopts a modular design, facilitating maintenance and expansion.

[0006] CN113386527B provides a thermal management system for a pure electric vehicle, including a first refrigerant circulation loop, a second refrigerant circulation loop, a first coolant circulation loop, and a second coolant circulation loop. The different circulation loops are connected or operate independently through the control of three-way valves and four-way valves. This system can flexibly utilize various heating energy-saving technologies, such as heat pump technology and electric drive waste heat utilization.

[0007] However, existing liquid-cooled energy storage thermal management units for rail transit generally adopt a mixed assembly design of water circuits and electrical control components, which has the following technical problems: First, the mixed arrangement of the liquid cooling system and the electrical control system makes it susceptible to electrical safety hazards when the liquid cooling system leaks, seriously threatening the safe operation of the system. Second, the mixed assembly of water circuits and electrical control components complicates system assembly and maintenance, increasing maintenance costs and difficulty. Third, the external temperature environment of the electrical control component box is easily affected by heat-generating components such as pipes, leading to a deterioration of the operating environment of electronic components and shortening their lifespan. Finally, the high integration of components in rail transit vehicles and the limited available space, coupled with the compact design of existing liquid cooling units, further increase the difficulty of assembly and maintenance.

[0008] Therefore, there is an urgent need for a new type of liquid-cooled energy storage thermal management unit for rail transit, which can effectively solve the safety hazards caused by the mixed arrangement of liquid cooling system and electrical control system, simplify assembly and maintenance process, improve the working environment of electrical control components, and achieve efficient thermal management function in a limited space. Summary of the Invention

[0009] The technical problem to be solved by this utility model is to address the following issues in the existing rail transit liquid cooling unit design: electrical safety hazards due to liquid leakage, troublesome assembly and maintenance, shortened lifespan of electronic components due to the influence of heat-generating components such as pipes on the external temperature environment of the electrical control component box, and increased assembly and maintenance difficulty due to the high integration of rail transit vehicle components and limited available space, which makes the liquid cooling unit design compact.

[0010] The objective of this utility model is achieved through the following technical solution: A liquid-cooled energy storage thermal management unit for rail transit includes a cabinet, a liquid-cooled circulation loop, a refrigerant circulation loop, a coolant inlet pipe, a coolant outlet pipe, and an electrical control component. The cabinet is internally divided into a condensation chamber, a liquid-cooled medium distribution chamber, and an electrical control chamber according to their functions. The chambers are thermally isolated from each other by airtight partitions. The refrigerant circulation loop is arranged in the condensation chamber, and the liquid-cooled circulation loop is arranged in the liquid-cooled medium distribution chamber. The liquid-cooled circulation loop and the refrigerant circulation loop are thermally coupled through a plate heat exchanger. The coolant inlet pipe is connected to the liquid-cooled circulation loop, and the coolant outlet pipe is connected to both the liquid-cooled circulation loop and the refrigerant circulation loop. The electrical control component is located in the electrical control chamber to control the liquid-cooled circulation loop and the refrigerant circulation loop.

[0011] Furthermore, the liquid cooling circulation loop along the coolant flow direction includes at least a first PTC electric heater, a circulation pump, a second PTC electric heater, an electric three-way valve, and a radiator. The coolant inlet pipe and the first PTC electric heater are connected to the inlet of the circulation pump via a pipeline. One end of the second PTC electric heater is connected to the outlet of the circulation pump, and the other end of the second PTC electric heater is connected to the electric three-way valve. One end of the electric three-way valve is connected to the inlet of the plate heat exchanger via a branch, and the other end of the electric three-way valve is connected to the inlet of the radiator via another branch. The outlets of the radiator and the plate heat exchanger converge and are connected to the coolant outlet pipe. The first PTC electric heater, the circulation pump, the second PTC electric heater, the electric three-way valve, and the plate heat exchanger are all integrated in the liquid cooling medium distribution chamber, and the radiator is arranged in the condensation chamber.

[0012] Furthermore, the refrigerant circulation loop includes at least a compressor, a condenser, a filter, and a gas-liquid separator along the refrigerant flow direction. One end of the gas-liquid separator is thermally coupled to the plate heat exchanger via a pipeline, and the other end of the gas-liquid separator is connected to the inlet end of the compressor via a pipeline. The inlet end of the filter is connected to the outlet end of the compressor, and the outlet end of the filter is thermally coupled to the plate heat exchanger via a pipeline. The compressor, condenser, and gas-liquid separator are all integrated in the condensation chamber, and the filter is arranged in the liquid cooling medium distribution chamber.

[0013] Furthermore, two sets of radiators and two sets of condensers are provided, with the radiators arranged above the condensers.

[0014] Furthermore, the condensation chamber is also equipped with a condensing fan, which is arranged between the two radiators.

[0015] Furthermore, the liquid cooling medium distribution chamber is also equipped with an expansion tank, which is arranged on one side of the electric three-way valve.

[0016] Furthermore, the pipes and components inside the cabinet are all arranged in a stacked manner.

[0017] Furthermore, the electrical control components include at least a control power supply, a frequency converter, a filter capacitor, and a controller, all of which are integrated within the electrical control compartment to control the liquid cooling circulation loop and the refrigerant circulation loop.

[0018] Furthermore, the electrical control compartment is also equipped with a control compartment cover; the liquid cooling medium distribution compartment is also equipped with a liquid cooling compartment cover.

[0019] Furthermore, the condensation chamber is provided with a central condensation cover plate, a right condensation cover plate, and a left condensation cover plate. The central condensation cover plate is located above the condensation fan, and the right and left condensation cover plates are located above the two radiators, respectively.

[0020] The beneficial effects of this utility model are as follows: 1. Due to the adoption of three independent space designs—the condensation chamber, the liquid cooling medium distribution chamber, and the electrical control chamber—and the thermal isolation between each chamber by airtight partitions, leakage of liquid cooling pipes will not affect the electrical control component box, thus effectively avoiding potential electrical safety hazards. 2. Because the electrical control compartment and the liquid cooling medium distribution compartment are thermally isolated by an airtight partition, the external temperature environment of the electrical control component box will not be affected by the liquid cooling heating pipes, thereby extending the service life of electronic components. 3. Because the pipelines involved in the liquid cooling circulation loop are designed in a layered manner, the assemblability and maintainability are enhanced, and space is saved, solving the problem of high integration of rail transit vehicle components and limited available space. 4. The machine cover is divided into five parts: control compartment cover, liquid cooling compartment cover, condenser middle cover, condenser right cover, and condenser left cover, which facilitates assembly and maintenance and further improves the maintainability of the equipment. Attached Figure Description

[0021] Figure 1 This is a three-dimensional structural diagram of the liquid-cooled energy storage thermal management unit of this utility model; Figure 2 This is a first exploded schematic diagram of the liquid-cooled energy storage thermal management unit of this utility model; Figure 3 This is a second exploded view of the liquid-cooled energy storage thermal management unit of this utility model; Figure 4 This is the third exploded view of the liquid-cooled energy storage thermal management unit of this utility model; Figure 5 This is the fourth exploded view of the liquid-cooled energy storage thermal management unit of this utility model; Figure 6 This is a schematic diagram of the liquid cooling circulation loop of this utility model; Figure 7 This is a schematic diagram of the refrigerant circulation loop of this utility model; Figure 8 This is a system schematic diagram of the liquid-cooled energy storage thermal management unit of this utility model.

[0022] The attached diagram is labeled as follows: 1-Cabinet, 11-Condensing Chamber, 12-Liquid Cooling Medium Distribution Chamber, 13-Electrical Control Chamber, 14-Control Chamber Cover, 15-Liquid Cooling Chamber Cover, 16-Condensing Middle Cover, 17-Condensing Right Cover, 18-Condensing Left Cover, 2-Liquid Cooling Circulation Loop, 21-First PTC Electric Heater, 22-Circulation Pump, 23-Second PTC Electric Heater, 24-Electric Three-Way Valve, 25-Radiator, 3-Refrigerant Circulation Loop, 3 1-Compressor, 32-Condenser, 33-Filter, 34-Gas-liquid separator, 4-Coolant inlet pipe, 5-Coolant outlet pipe, 61-Control power supply, 62-Inverter, 63-Filter capacitor, 64-Controller, 7-Plate heat exchanger, 8-Condenser fan, 9-Expansion tank, 102-Temperature sensor, 103-Pressure sensor, 104-Pressure switch, 105-Needle valve, 106-Electronic expansion valve, and 107-Check valve. Detailed Implementation

[0023] To facilitate understanding by those skilled in the art, the following description is provided in conjunction with embodiments and appendices. Figure 1-8 The present invention will be further described below. The content mentioned in the embodiments is not intended to limit the present invention.

[0024] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on the other component or indirectly on that other component.

[0025] When a component is said to be "connected to" another component, it can be directly connected to the other component or indirectly connected to that other component.

[0026] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0028] In the description of this application, "multiple" means two or more, unless otherwise expressly and specifically defined.

[0029] See Figure 1-7A liquid-cooled energy storage thermal management unit for rail transit includes a cabinet 1, a liquid-cooled circulation loop, a refrigerant circulation loop, a coolant inlet pipe 4, a coolant outlet pipe 5, and an electrical control component. The cabinet 1 is divided into a condensation chamber 11, a liquid-cooled medium distribution chamber 12, and an electrical control chamber 13 according to their functions. Each chamber is thermally isolated by an airtight partition, which realizes thermal isolation between different functional areas and prevents heat interference between them.

[0030] The refrigerant circulation loop is located in the condenser chamber 11, and the liquid-cooled circulation loop is located in the liquid-cooled medium distribution chamber 12. The liquid-cooled circulation loop and the refrigerant circulation loop are thermally coupled via a plate heat exchanger 7, enabling heat exchange between the two circulation systems. The coolant inlet pipe 4 is connected to the liquid-cooled circulation loop, and the coolant outlet pipe 5 is connected to both the liquid-cooled circulation loop and the refrigerant circulation loop, forming a complete coolant flow path. The electrical control components are located in the electrical control chamber 13 to control the liquid-cooled circulation loop and the refrigerant circulation loop, ensuring the normal operation of the entire system.

[0031] The liquid-cooled circulation loop, along the coolant flow direction, includes a first PTC electric heater 21, a circulation pump 22, a second PTC electric heater 23, an electric three-way valve 24, and a radiator 25. The coolant inlet pipe 4 connects to the first PTC electric heater 21 via a pipeline and is connected to the inlet of the circulation pump 22. One end of the second PTC electric heater 23 connects to the outlet of the circulation pump 22, and the other end connects to the electric three-way valve 24. One end of the electric three-way valve 24 connects to the inlet of the plate heat exchanger 7 via a branch, and the other end connects to the inlet of the radiator 25 via another branch. The outlets of the radiator 25 and the plate heat exchanger 7 converge and connect to the coolant outlet pipe 5, forming a complete liquid-cooled circulation system. The first PTC electric heater 21, the circulating pump 22, the second PTC electric heater 23, the electric three-way valve 24, and the plate heat exchanger 7 are all integrated in the liquid cooling medium distribution chamber 12, while the radiator 25 is arranged in the condensation chamber 11. This layout design allows the liquid cooling circulation loop to select different cooling paths as needed, improving the system's flexibility and adaptability.

[0032] The refrigerant circulation loop, along the refrigerant flow direction, includes a compressor 31, a condenser 32, a filter 33, and a gas-liquid separator 34. One end of the gas-liquid separator 34 is thermally coupled to the plate heat exchanger 7 via a pipe, and the other end of the gas-liquid separator 34 is connected to the inlet end of the compressor 31 via a pipe. The inlet end of the filter 33 is connected to the outlet end of the compressor 31, and the outlet end of the filter 33 is thermally coupled to the plate heat exchanger 7 via a pipe. The compressor 31, condenser 32, and gas-liquid separator 34 are all integrated within the condenser chamber 11, while the filter 33 is arranged within the liquid cooling medium distribution chamber 12. This layout design allows the refrigerant circulation loop to efficiently exchange heat with the liquid cooling circulation loop, improving the overall system's thermal management efficiency.

[0033] Two sets of radiators 25 and two sets of condensers 32 are provided, with the radiators 25 positioned above the condensers 32. This arrangement increases the heat dissipation area and improves heat dissipation efficiency. A condenser fan 8 is also provided inside the condenser chamber 11, positioned between the two radiators 25. The condenser fan 8 forces airflow, accelerates heat dissipation, and further improves heat dissipation efficiency.

[0034] An expansion tank 9 is also provided inside the liquid cooling medium distribution chamber 12, and the expansion tank 9 is arranged on one side of the electric three-way valve 24. The expansion tank 9 can compensate for the change in coolant volume caused by temperature changes in the liquid cooling system and maintain the stable operation of the system.

[0035] The piping and components within cabinet 1 are arranged in a stacked manner (this is existing technology and is only used for application purposes). This stacked design not only saves space but also improves the system's compactness and stability, and facilitates installation and maintenance.

[0036] The electrical control components include a control power supply 61, a frequency converter 62, a filter capacitor 63, and a controller 64. These components are all integrated within the electrical control compartment 13 to control the liquid cooling circulation loop and the refrigerant circulation loop. These electrical control components work together to ensure the normal operation and efficient control of the entire thermal management system.

[0037] The electrical control compartment 13 is also equipped with a control compartment cover 14; the liquid cooling medium distribution compartment 12 is also equipped with a liquid cooling compartment cover 15. The condenser compartment 11 is equipped with a central condenser cover 16, a right condenser cover 17, and a left condenser cover 18. The central condenser cover 16 is located above the condenser fan 8, while the right condenser cover 17 and the left condenser cover 18 are located above the two radiators 25, respectively. These covers facilitate the inspection and maintenance of each compartment, and also serve a protective and sealing function.

[0038] See Figure 8The schematic diagram of refrigeration and heat exchange is as follows: In refrigeration mode, refrigerant is first charged into the refrigerant circulation loop. Compressor 31 generates high-temperature, high-pressure gas, which is then cooled into a medium-temperature, high-pressure liquid by condenser 32. After passing through a dry filter 33, it flows through electronic expansion valve 106 to produce a low-temperature, low-pressure mist-like liquid refrigerant. Finally, it exchanges heat with the coolant in the liquid-cooled circulation loop at plate heat exchanger 7. In the liquid-cooled circulation loop, the coolant first flows from the coolant inlet pipe 4 to the filter 33. The first PTC electric heater 21 is then drawn into the circulating pump 22, and the coolant is pumped out by the circulating pump 22, flowing to the second PTC electric heater 23 and then to the electric three-way valve 24. From here, two modes can be selected: 1. The coolant flows from the electric three-way valve 24 to the plate heat exchanger 7, where it exchanges heat, and then flows out from the unit's coolant outlet pipe 5; 2. The coolant flows from the electric three-way valve 24 to the radiator 25, where it exchanges heat, and then flows out from the outlet of the unit's coolant outlet pipe 5. In both modes, after the coolant flows out from the outlet of the unit's coolant outlet pipe 5, it passes through the liquid-cooled plate channel, carrying away the heat from the battery cells, and then returns to the inlet of the liquid-cooled unit, where it is drawn in by the circulating pump 22, and the cycle repeats.

[0039] This liquid-cooled energy storage thermal management unit for rail transit achieves efficient thermal management through a rational structural design and functional layout, meeting the thermal management requirements of rail transit energy storage systems. The liquid cooling circulation loop and refrigerant circulation loop work together, automatically adjusting the cooling path according to different operating conditions to ensure the energy storage system always operates within its optimal temperature range, extending its service life and improving its safety and reliability.

[0040] The above embodiments are preferred implementations of this utility model. In addition, this utility model can also be implemented in other ways. Any obvious substitutions without departing from the concept of this utility model are within the protection scope of this utility model.

Claims

1. A liquid-cooled energy storage thermal management unit for rail transit, characterized in that: The system includes a cabinet, a liquid cooling circulation loop, a refrigerant circulation loop, a coolant inlet pipe, a coolant outlet pipe, and an electrical control assembly. The cabinet is internally divided into a condenser compartment, a liquid cooling medium distribution compartment, and an electrical control compartment, which are thermally isolated from each other by airtight partitions. The refrigerant circulation loop is located in the condenser compartment, and the liquid cooling circulation loop is located in the liquid cooling medium distribution compartment. The liquid cooling circulation loop and the refrigerant circulation loop are thermally coupled through a plate heat exchanger. The coolant inlet pipe is connected to the liquid cooling circulation loop, and the coolant outlet pipe is connected to both the liquid cooling circulation loop and the refrigerant circulation loop. The electrical control assembly is located in the electrical control compartment to control the liquid cooling circulation loop and the refrigerant circulation loop.

2. The liquid-cooled energy storage thermal management unit for rail transit according to claim 1, characterized in that: The liquid cooling circulation loop, along the coolant flow direction, includes at least a first PTC electric heater, a circulation pump, a second PTC electric heater, an electric three-way valve, and a radiator. The coolant inlet pipe and the first PTC electric heater are connected to the inlet of the circulation pump via a pipeline. One end of the second PTC electric heater is connected to the outlet of the circulation pump, and the other end of the second PTC electric heater is connected to the electric three-way valve. One end of the electric three-way valve is connected to the inlet of the plate heat exchanger via a branch, and the other end of the electric three-way valve is connected to the inlet of the radiator via another branch. The outlets of the radiator and the plate heat exchanger converge and connect to the coolant outlet pipe. The first PTC electric heater, the circulation pump, the second PTC electric heater, the electric three-way valve, and the plate heat exchanger are all integrated in the liquid cooling medium distribution chamber, and the radiator is arranged in the condensation chamber.

3. The liquid-cooled energy storage thermal management unit for rail transit according to claim 2, characterized in that: The refrigerant circulation loop includes at least a compressor, a condenser, a filter, and a gas-liquid separator along the refrigerant flow direction. One end of the gas-liquid separator is thermally coupled to the plate heat exchanger via a pipeline, and the other end of the gas-liquid separator is connected to the inlet end of the compressor via a pipeline. The inlet end of the filter is connected to the outlet end of the compressor, and the outlet end of the filter is thermally coupled to the plate heat exchanger via a pipeline. The compressor, condenser, and gas-liquid separator are all integrated in the condensation chamber, and the filter is arranged in the liquid cooling medium distribution chamber.

4. A liquid-cooled energy storage thermal management unit for rail transit according to claim 3, characterized in that: Two sets of radiators and two sets of condensers are provided, with the radiators positioned above the condensers.

5. A liquid-cooled energy storage thermal management unit for rail transit according to claim 4, characterized in that: The condensing chamber is also equipped with a condensing fan, which is arranged between the two radiators.

6. A liquid-cooled energy storage thermal management unit for rail transit according to claim 2, characterized in that: The liquid cooling medium distribution chamber is also equipped with an expansion tank, which is located on one side of the electric three-way valve.

7. A liquid-cooled energy storage thermal management unit for rail transit according to claim 2 or 3, characterized in that: The pipes and components inside the cabinet are all arranged in a stacked manner.

8. A liquid-cooled energy storage thermal management unit for rail transit according to claim 1, characterized in that: The electrical control components include at least a control power supply, a frequency converter, a filter capacitor, and a controller. The control power supply, frequency converter, filter capacitor, and controller are all integrated in the electrical control compartment to control the liquid cooling circulation loop and the refrigerant circulation loop.

9. A liquid-cooled energy storage thermal management unit for rail transit according to claim 1, characterized in that: The electrical control compartment is also equipped with a control compartment cover; the liquid cooling medium distribution compartment is also equipped with a liquid cooling compartment cover.

10. A liquid-cooled energy storage thermal management unit for rail transit according to claim 4, characterized in that: The condensation chamber is equipped with a central condenser cover, a right condenser cover, and a left condenser cover. The central condenser cover is located above the condenser fan, and the right and left condenser covers are located above the two radiators, respectively.

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