Railway vehicle machine room heat dissipation system and control method thereof
By combining a heat dissipation device and a refrigeration air conditioner in the mechanical compartment of the rail vehicle, and utilizing the vehicle's running air and enclosed structure, the problems of high energy consumption and dust impact were solved, thereby improving temperature control and equipment reliability.
Patent Information
- Application Number
- CN202511118236.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-11
- Publication Date
- 2025-11-18
AI Technical Summary
The air conditioning in the existing rail vehicle machinery room has high energy consumption and may cause electrical failures or component damage in extreme temperature environments. In addition, dust entering the room affects the reliability and lifespan of the equipment.
It adopts a composite cooling method that combines heat dissipation devices and air conditioning. It uses the vehicle's running air to dissipate heat through refrigerant circulation pipelines and heat dissipation devices, combined with a closed mechanical room structure to achieve temperature control.
It reduces energy consumption, decreases noise, improves equipment reliability and lifespan, reduces maintenance costs, and ensures that the temperature is within a suitable range.
Smart Images
Figure CN120963789A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of heat dissipation of rail vehicles, and particularly relates to a heat dissipation system for a mechanical room of a rail vehicle and a control method thereof. BACKGROUND
[0002] With the rapid development of rail vehicles, the use environment of rail vehicles is becoming more and more diversified and complex, such as desert, coal dust, willow catkins, rain and snow, and the like. The requirements for the filtering system of the mechanical room of a rail vehicle are becoming higher and higher. At present, only air conditioners are used in the mechanical room for air temperature adjustment. The indoor unit of the air conditioner is arranged in the mechanical room, and the outdoor unit of the air conditioner is arranged on the top of the rail vehicle. Heat exchange is performed through the flow of refrigerant between the indoor unit and the outdoor unit. The energy consumption is high. At the same time, since the mechanical room is not closed, more dust enters the mechanical room, which affects the reliability and service life of the electrical components in the vehicle. In addition, when the rail vehicle operates in high-temperature conditions in summer, local high-temperature points may occur in the mechanical room, thereby causing electrical faults and accelerating the fatigue of components. In winter, the local temperature in the mechanical room may be too low, which affects the operation of mechanical components, or the wires and cables and belts become stiff due to low temperature and cause problems. SUMMARY
[0003] In view of the existing technical problems, the present application aims to provide a heat dissipation system for a mechanical room of a rail vehicle and a control method thereof. The heat dissipation system can solve the technical problem of how to reduce the energy consumption of the mechanical room in the prior art.
[0004] To achieve the above-mentioned purpose, the technical solution adopted by the present application is as follows:
[0005] A heat dissipation system for a mechanical room of a rail vehicle comprises an outdoor unit arranged outside the rail vehicle and an indoor unit arranged in the mechanical room. The refrigerant discharged from the indoor unit flows into the outdoor unit through a first circulating pipeline, and the refrigerant discharged from the outdoor unit enters the indoor unit through a second circulating pipeline. The structural features are as follows: a heat dissipation device is further arranged outside the rail vehicle, and a third circulating pipeline and a fourth circulating pipeline are connected to the heat dissipation device. The outer end of the third circulating pipeline is in communication with the first circulating pipeline, and a first three-way valve is arranged at the communication position. The outer end of the fourth circulating pipeline is in communication with the second circulating pipeline, and a first valve is arranged on the second circulating pipeline. The first valve is arranged between the communication position of the second circulating pipeline and the fourth circulating pipeline and the outdoor unit. The fourth circulating pipeline and the first circulating pipeline are in communication through a fifth circulating pipeline, and a second three-way valve is arranged at the communication position of the fourth circulating pipeline and the fifth circulating pipeline.
[0006] When the temperature in the mechanical room is higher than the threshold range, the first valve, the indoor unit and the outdoor unit are opened, the second three-way valve is closed, and the first three-way valve is operated so that the refrigerant in the indoor unit exchanges heat and then enters the outdoor unit through the first circulation pipeline to exchange heat, and the refrigerant in the outdoor unit exchanges heat and then returns to the indoor unit through the second circulation pipeline, so that the temperature in the mechanical room is always maintained within the threshold range. This is the common air conditioning refrigeration mode. When the temperature in the mechanical room is lower than the threshold range, the indoor unit is opened, the first valve and the outdoor unit are closed, and the first three-way valve and the second three-way valve are operated so that the refrigerant in the indoor unit exchanges heat and then enters the heat dissipation device through the third circulation pipeline, the heat dissipation device is cooled by the vehicle running wind, and the refrigerant in the heat dissipation device exchanges heat and then returns to the indoor unit through the fourth circulation pipeline and the second circulation pipeline, so that the temperature in the mechanical room is always maintained within the threshold range. When the temperature in the mechanical room is within the threshold range, the indoor unit and the first valve are opened, and the first three-way valve and the second three-way valve are operated so that the refrigerant in the indoor unit exchanges heat and then enters the heat dissipation device through the third circulation pipeline to exchange heat, the refrigerant in the heat dissipation device exchanges heat and then enters the outdoor unit through the fourth circulation pipeline, the fifth circulation pipeline and the first circulation pipeline, and finally returns to the indoor unit through the second circulation pipeline, so that the temperature in the mechanical room is always maintained within the threshold range. The threshold range is set according to the working temperature range of the mechanical room, and the general working temperature of the mechanical room is 20-40℃. The rail vehicle mechanical room heat dissipation system of the present application uses a combined cooling method of heat dissipation device and refrigeration air conditioner, combines the characteristics of the rail vehicle operating environment, uses the vehicle running wind to cool the refrigerant flowing through the heat dissipation device, and achieves the purposes of energy saving and noise reduction.
[0007] Preferably, the heat dissipation device adopts a distributed structure, and comprises a plurality of heat dissipation branches, each heat dissipation branch comprising a plurality of heat dissipation modules connected in series or in parallel, and an input valve being arranged at the input end of each heat dissipation branch. The input end of each heat dissipation branch is connected with the third circulation pipeline, and the output end of each heat dissipation branch is connected with the fourth circulation pipeline. By arranging the input valve, one or more heat dissipation branches can be selectively opened according to the heat dissipation amount, and the heat dissipation capacity of the heat dissipation device can be further adjusted.
[0008] Preferably, the heat dissipation module comprises a first heat dissipation pipe and a second heat dissipation pipe arranged oppositely, and a plurality of third heat dissipation pipes arranged between the first heat dissipation pipe and the second heat dissipation pipe, both ends of the plurality of third heat dissipation pipes being connected with the first heat dissipation pipe and the second heat dissipation pipe respectively. The refrigerant input into the heat dissipation branch is input into the plurality of third heat dissipation pipes through the first heat dissipation pipe and is output through the second heat dissipation pipe. The rail vehicle mechanical room heat dissipation system of the present application uses running wind for heat dissipation, has no high-power moving parts, is high in safety, reduces noise, and significantly reduces energy consumption.
[0009] Preferably, the first and second heat dissipation pipes are arranged along the length or width direction of the rail vehicle, the first heat dissipation pipe is arranged above the second heat dissipation pipe, and the third heat dissipation pipe is connected perpendicularly to the first and second heat dissipation pipes.
[0010] Specifically, the heat dissipation device is arranged on the roof, bottom or side wall of the rail vehicle.
[0011] Preferably, the mechanical room adopts a sealed structure. The sealed mechanical room can reduce the entry of dust and other particulate matters into the mechanical room, thereby reducing the wear of internal equipment and prolonging the service life thereof. Meanwhile, the IP level of the electrical screen cabinet in the mechanical room can be appropriately reduced, the cabinet body can be made into a grating structure, the ventilation and heat dissipation of the electrical components inside the screen cabinet can be facilitated, and the cost of the screen cabinet can be reduced. The rail vehicle mechanical room heat dissipation system provided by the application can reduce the cleaning and maintenance work caused by the accumulation of dust on the screen cabinet in the sealed mechanical room, control the air temperature in the mechanical room within a proper range, thereby reducing the long-term maintenance cost and prolonging the service life of the electrical components in the mechanical room, and improving the reliability and stability of the system.
[0012] Preferably, the first temperature sensor, the first three-way valve, the second three-way valve, the first valve, the heat dissipation device, the outdoor unit and the indoor unit are electrically connected to the control system. The control system controls the opening and closing states of the first three-way valve, the second three-way valve, the first valve and the outdoor unit, and the number of opened heat dissipation modules in the heat dissipation device according to the temperature in the mechanical room, so that the temperature in the mechanical room is always maintained within the corresponding threshold range.
[0013] Preferably, a delivery pump is arranged on the fourth circulation pipeline and between the second three-way valve and the heat dissipation device. When the refrigerant flow is large, the delivery pump can be started to work, so as to accelerate the circulation of the refrigerant and increase the heat dissipation capacity of the heat dissipation device.
[0014] Based on the same inventive concept, the application further provides a rail vehicle mechanical room heat dissipation control method, which adopts the rail vehicle mechanical room heat dissipation system as described above and includes the following steps:
[0015] Step S1: collecting the temperature in the mechanical room;
[0016] Step S2: when the collected temperature in the mechanical room is higher than the threshold range, the first valve, the indoor unit and the outdoor unit are opened, the second three-way valve is closed, the first three-way valve is operated to make the refrigerant in the indoor unit exchange heat and then enter the outdoor unit through the first circulation pipeline to exchange heat, and the refrigerant in the outdoor unit exchanges heat and then returns to the indoor unit through the second circulation pipeline, so that the temperature in the mechanical room is always maintained within the threshold range.
[0017] When the temperature in the mechanical compartment is lower than the threshold range, the indoor unit is turned on, the outdoor unit and the first valve are turned off, the first three-way valve and the second three-way valve are operated so that the refrigerant in the indoor unit is heat-exchanged and then enters the heat dissipation device through the third circulating pipeline to be heat-exchanged, and the refrigerant in the heat dissipation device is heat-exchanged and then returns to the indoor unit through the fourth circulating pipeline and the second circulating pipeline, so that the temperature in the mechanical compartment is always maintained within the threshold range.
[0018] When the temperature in the mechanical compartment is within the threshold range, the indoor unit and the first valve are turned on, the first three-way valve and the second three-way valve are operated so that the refrigerant in the indoor unit is heat-exchanged and then enters the heat dissipation device through the third circulating pipeline to be heat-exchanged, the refrigerant in the heat dissipation device is heat-exchanged and then enters the outdoor unit through the fourth circulating pipeline, the fifth circulating pipeline and the first circulating pipeline, and finally returns to the indoor unit through the second circulating pipeline, so that the temperature in the mechanical compartment is always maintained within the threshold range.
[0019] The threshold range is set according to the working temperature range of the mechanical compartment.
[0020] Specifically, in step S2, when the temperature in the mechanical compartment is lower than the threshold range, the number of open heat dissipation modules in the heat dissipation device is adjusted as needed; when the temperature in the mechanical compartment is within the threshold range, all the heat dissipation modules in the heat dissipation device are turned on, the outdoor unit is turned off, and if the temperature in the mechanical compartment continues to rise, the outdoor unit is turned on so that the refrigerant is further cooled by the outdoor unit before returning to the indoor unit, so that the temperature in the mechanical compartment is always maintained within the threshold range. When the temperature in the mechanical compartment is within the threshold range, the running air heat dissipation device is preferentially used for heat dissipation, and the energy consumption is minimized. If the temperature in the mechanical compartment continues to rise, the outdoor unit is started to cool, so that the temperature in the mechanical compartment is always maintained within a reasonable range.
[0021] Compared with the prior art, the beneficial effects of the present application are as follows:
[0022] 1. The rail vehicle mechanical compartment heat dissipation system and the control method thereof combine the composite cooling mode of the heat dissipation device and the refrigeration air conditioner, combine the characteristics of the rail vehicle operating environment, use the vehicle running air to dissipate heat from the refrigerant flowing through the heat dissipation device, and achieve the purposes of energy saving and noise reduction.
[0023] 2. The rail vehicle mechanical compartment heat dissipation system uses a sealed structure for the mechanical compartment to reduce the entry of dust and other particulate matters into the mechanical compartment, which helps to reduce the wear of internal equipment and prolong the service life of the equipment. At the same time, the IP level of the electrical screen cabinet in the mechanical compartment can be appropriately reduced, the cabinet body can be made of a grating structure, the ventilation and heat dissipation of the electrical components inside the screen cabinet are facilitated, and the cost of the screen cabinet can be reduced.
[0024] 3. The rail vehicle mechanical room heat dissipation system of the present application, the sealed mechanical room can reduce the cleaning and maintenance work caused by the dust accumulation on the mechanical room screen cabinet, thereby reducing the long-term maintenance cost.
[0025] 4. The rail vehicle mechanical room heat dissipation system of the present application, compared with the prior art non-closed forced air cooling heat dissipation, by adopting the heat management scheme of the closed mechanical room, the mechanical room temperature is kept within a suitable temperature range, thereby achieving the purpose of improving the reliability and service life of the electrical components in the mechanical room.
[0026] 5. The rail vehicle mechanical room heat dissipation system of the present application, which utilizes the running wind for heat dissipation, has no high-power moving parts, is high in safety, reduces noise, and significantly reduces energy consumption. BRIEF DESCRIPTION OF DRAWINGS
[0027] Figure 1 is a structural schematic diagram of the rail vehicle mechanical room heat dissipation system of the present application;
[0028] Figure 2 is Figure 1 a schematic diagram of the connection structure of the heat dissipation device, indoor unit and outdoor unit in
[0029] Figure 3 is Figure 2 a structural schematic diagram of the heat dissipation device in
[0030] Figure 4 is Figure 3 a structural schematic diagram of the heat dissipation module in
[0031] Figure 5 is Figure 2 a structural schematic diagram of the indoor unit in
[0032] Figure 6 is Figure 2 a structural schematic diagram of the outdoor unit in
[0033] in the drawings
[0034] 1 - heat dissipation device; 101 - heat dissipation module; 101 -1 - first heat dissipation pipe; 101 -2 - second heat dissipation pipe; 101 -3 - third heat dissipation pipe; 102 - fifth valve; 2 - outdoor unit; 201 - compressor; 202 - condenser; 203 - condensing fan; 204 - stop valve; 3 - indoor unit; 301 - evaporating fan; 302 - evaporator; 4 - control system; 5 - first three-way valve; 6 - second three-way valve; 7 - first valve; 8 - second valve; 9 - delivery pump; 10 - first temperature sensor; 11 - fifth circulating pipeline; 12 - rail vehicle; 13 - mechanical room; 14 - first circulating pipeline; 15 - second circulating pipeline; 16 - third circulating pipeline; 17 - fourth circulating pipeline. DETAILED DESCRIPTION
[0035] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. For ease of description, the terms "upper," "lower," "left," and "right" used below only indicate that they correspond to the upper, lower, left, and right directions in the accompanying drawings and do not limit the structure.
[0036] like Figure 1 As shown, a cooling system for the mechanical compartment of a rail vehicle according to this embodiment includes an outdoor unit 2 and a cooling device 1 installed on the top of the rail vehicle 12, a control system 4 installed inside the rail vehicle 12, and an indoor unit 3 and a first temperature sensor 10 installed in the mechanical compartment 13 of the rail vehicle 12. The mechanical compartment 13 adopts a closed structure. Figure 3 As shown, the heat dissipation device 1 includes two heat dissipation branches, each with an inlet valve 102 at its inlet. Each heat dissipation branch contains multiple heat dissipation modules 101, which are connected in series via pipes. Figure 4 As shown, the heat dissipation module 101 includes a first heat dissipation pipe 101-1 and a second heat dissipation pipe 101-2 arranged opposite to each other, and eleven third heat dissipation pipes 101-3 arranged between the first heat dissipation pipe 101-1 and the second heat dissipation pipe 101-2. The two ends of the eleven third heat dissipation pipes 101-3 are respectively connected to the first heat dissipation pipe 101-1 and the second heat dissipation pipe 101-2. The first heat dissipation pipe 101-1 and the second heat dissipation pipe 101-2 are arranged parallel to each other along the length of the rail vehicle 12, with the first heat dissipation pipe 101-1 positioned directly above the second heat dissipation pipe 101-2. The third heat dissipation pipes 101-3 are perpendicularly connected to both the first heat dissipation pipe 101-1 and the second heat dissipation pipe 101-2, and are perpendicular to the top of the rail vehicle 12. Fluid flowing into the heat dissipation module 101 flows through the second heat dissipation pipe 101-2 into the eleven third heat dissipation pipes 101-3, and then flows out through the first heat dissipation pipe 101-1. Figure 5 As shown, the indoor unit 3 includes an evaporating fan 301 and an evaporator 302, with the evaporating fan 301 positioned on the evaporating side of the evaporator 302. Figure 6 As shown, outdoor unit 2 includes compressor 201, condenser 202, condensing fan 203, and shut-off valve 204. Compressor 201, condenser 202, and shut-off valve 204 are connected in series via pipelines. Condensing fan 203 is located on one side of condenser 202. Figure 2As shown, the evaporator 302 is connected with the compressor 201 through the first circulation pipeline 14, and the stop valve 204 is connected with the compressor 201 through the second circulation pipeline 15. The input end of the heat dissipation device 1 is connected with the third circulation pipeline 16, the outer end of the third circulation pipeline 16 is connected with the first circulation pipeline 14, and the first three-way valve 5 is arranged at the connection position. The output end of the heat dissipation device 1 is connected with the fourth circulation pipeline 17, the outer end of the fourth circulation pipeline 17 is connected with the second circulation pipeline 15, and the first valve 7 is arranged on the second circulation pipeline 15 between the connection position of the second circulation pipeline 15 and the fourth circulation pipeline 17 and the outdoor unit 2. The fourth circulation pipeline 17 is connected with the first circulation pipeline 14 through the fifth circulation pipeline 11, the second three-way valve 6 is arranged at the connection position of the fourth circulation pipeline 17 and the fifth circulation pipeline 11, and the second valve 8 is arranged on the fifth circulation pipeline 11. The fourth circulation pipeline 17 is provided with the delivery pump 9, and the delivery pump 9 is arranged between the second three-way valve 6 and the heat dissipation device 1. The first temperature sensor 10, the first three-way valve 5, the second three-way valve 6, the first valve 7, the second valve 8, the input valve 102 arranged at the input end of the heat dissipation device 1, the outdoor unit 2 and the indoor unit 3 are electrically connected with the control system 4. The control system 4 controls the opening and closing states of the first three-way valve 5, the second three-way valve 6, the first valve 7, the second valve 8 and the outdoor unit 2, and the number of opened heat dissipation modules 101 in the heat dissipation device 1 according to the temperature in the machine room 13, so that the temperature in the machine room 13 is always maintained within the corresponding threshold range. In the embodiment, the air temperature threshold range in the machine room 13 is T2-T n = 20-40℃.
[0037] The embodiment also provides a heat dissipation control method for a machine room of a rail vehicle, which adopts the heat dissipation system for a machine room of a rail vehicle as described above, and includes the following steps.
[0038] Step S1: collecting the temperature in the machine room 13 by the first temperature sensor 10;
[0039] Step S2: when the collected temperature T1 in the mechanical compartment 13 is higher than 40℃, open the first valve 7, the indoor unit 3 and the outdoor unit 2, close the second three-way valve 6 and the second valve 8, operate the first three-way valve 5, and the first three-way valve 5 is in the state of inletting from the left and outletting from the right, so that the refrigerant in the indoor unit 3 absorbs heat in the mechanical compartment 13 in the evaporator 302 after evaporation, enters the compressor 201 in the outdoor unit 2 to be compressed into high-temperature and high-pressure gas, and then enters the condenser 202 to release heat to the environment outside the vehicle, and the refrigerant in the outdoor unit 2 is heat-exchanged and then returns to the indoor unit 3 through the second circulation pipeline 15, so that the temperature in the mechanical compartment 13 is always maintained within the range of 20-40℃; at this time, the mechanical compartment heat dissipation system is in the air conditioning refrigeration unit working mode, and the heat in the mechanical compartment 13 is effectively transferred and dissipated to the outside of the vehicle through this refrigeration mode, so as to realize the cooling effect;
[0040] When the collected temperature T1 in the mechanical compartment 13 is lower than 20℃, open the indoor unit 3, close the outdoor unit 2, the first valve 7 and the second valve 8, operate the first three-way valve 5 and the second three-way valve 6, the first three-way valve 5 is in the state of inletting from the left and outletting from the right, and the second three-way valve 6 is in the state of inletting from the right and outletting from the left, so that the refrigerant in the indoor unit 3 absorbs heat in the mechanical compartment 13 in the evaporator 302 after evaporation, enters the heat dissipation device 1 through the third circulation pipeline 16 to perform heat exchange, and the gaseous refrigerant is heat-exchanged with the refrigerant in the heat dissipation pipeline of the heat dissipation device 1 by using the shape wind of the rail vehicle 12 when running, and the gaseous refrigerant is condensed and released heat to become liquid, and then returns to the indoor unit 3 through the fourth circulation pipeline 17 and the second circulation pipeline 15 under the action of gravity or by the aid of the conveying pump 9, so that the temperature in the mechanical compartment 13 is always maintained within the range of 20-40℃; at this time, the mechanical compartment heat dissipation system is in the heat pipe evaporation heat dissipation working mode; wherein the number of opened heat dissipation modules in the heat dissipation device 1 is adjusted according to the need; when the external environment temperature of the rail vehicle 12 is relatively low, the liquid refrigerant can return to the indoor unit 3 by gravity; when the external environment temperature of the rail vehicle 12 is relatively high, the conveying pump 9 can be opened to accelerate the circulation of the refrigerant and increase the heat dissipation capacity;
[0041] When the temperature T1 in the mechanical room 13 is in the range of 20-40℃, the indoor unit 3, the first valve 7 and the second valve 8 are opened, the outdoor unit 2 is closed, the first three-way valve 5 and the second three-way valve 6 are operated, the first three-way valve 5 is left-in and right-out, and the second three-way valve 6 is left-in and right-out, so that the refrigerant in the indoor unit 3 is evaporated in the evaporator 302 after absorbing the heat in the mechanical room 13, enters the heat dissipation device 1 through the third circulation pipeline 16 to exchange heat, all the heat dissipation modules in the heat dissipation device 1 are opened, the heat exchange between the track vehicle 12 running and the refrigerant in the heat dissipation pipeline of the heat dissipation device 1 is maximized, the gaseous refrigerant is condensed and released heat to become liquid, and then enters the outdoor unit 2 through the fourth circulation pipeline 17, the fifth circulation pipeline 11 and the first circulation pipeline 14, and finally returns to the indoor unit 3 through the second circulation pipeline 15, so that the temperature in the mechanical room 13 is always maintained in the range of 20-40℃; at this time, the mechanical room heat dissipation system is in an intelligent working mode; if the temperature in the mechanical room 13 continues to rise, the outdoor unit 2 is opened, so that the refrigerant is further cooled in the outdoor unit 2 and then returns to the indoor unit 3, so that the temperature in the mechanical room 13 is always maintained in the threshold range.
[0042] The intelligent working mode combines the advantages of the refrigeration unit and the heat pipe evaporation heat dissipation, realizes the goals of high efficiency and energy saving and flexible adjustment, can automatically optimize the operating state under different environmental conditions, and improves the overall performance and reliability of the system.
[0043] The above embodiments should be understood as examples only for more clearly illustrating the application, and should not be used to limit the scope of the application. After reading the application, those skilled in the art can make various equivalent modifications to the embodiments, which fall within the scope defined by the appended claims of the application.
Claims
1. A heat dissipation system for a rail vehicle's machinery compartment, comprising an outdoor unit (2) disposed outside the rail vehicle (12) and an indoor unit (3) disposed inside the machinery compartment (13), wherein refrigerant discharged from the indoor unit (3) flows into the outdoor unit (2) through a first circulation pipe (14), and refrigerant discharged from the outdoor unit (2) enters the indoor unit (3) through a second circulation pipe (15); characterized in that: It also includes a heat dissipation device (1) installed outside the rail vehicle (13), which is connected to a third circulation pipe (16) and a fourth circulation pipe (17); The outer end of the third circulation pipeline (16) is connected to the first circulation pipeline (14), and a first three-way valve (5) is provided at the connection point; The outer end of the fourth circulation pipe (17) is connected to the second circulation pipe (15). The second circulation pipe (15) is provided with a first valve (7), which is located between the connection between the second circulation pipe (15) and the fourth circulation pipe (17) and the outdoor unit (2). The fourth circulation pipeline (17) is connected to the first circulation pipeline (14) through the fifth circulation pipeline (11), and a second three-way valve (6) is provided at the connection between the fourth circulation pipeline (17) and the fifth circulation pipeline (11).
2. The heat dissipation system for the mechanical compartment of a rail vehicle according to claim 1, characterized in that: The heat dissipation device (1) adopts a distributed structure. The heat dissipation device (1) includes multiple heat dissipation branches. Each heat dissipation branch includes multiple heat dissipation modules (101) connected in series or in parallel. Each heat dissipation branch has an input valve (102) at its input end. The input end of each heat dissipation branch is connected to the third circulation pipeline (16), and the output end of each heat dissipation branch is connected to the fourth circulation pipeline (17).
3. The heat dissipation system for the mechanical compartment of a rail vehicle according to claim 2, characterized in that: The heat dissipation module (101) includes a first heat dissipation pipe (101-1) and a second heat dissipation pipe (101-2) arranged opposite to each other, and a plurality of third heat dissipation pipes (101-3) arranged between the first heat dissipation pipe (101-1) and the second heat dissipation pipe (101-2). The two ends of the plurality of third heat dissipation pipes (101-3) are respectively connected to the first heat dissipation pipe (101-1) and the second heat dissipation pipe (101-2). The refrigerant input on the heat dissipation branch is input into the plurality of third heat dissipation pipes (101-3) through the first heat dissipation pipe (101-1) and output through the second heat dissipation pipe (101-2).
4. The heat dissipation system for the mechanical compartment of a rail vehicle according to claim 3, characterized in that: The first heat dissipation pipe (101-1) and the second heat dissipation pipe (101-2) are both arranged along the length or width direction of the rail vehicle (12). The first heat dissipation pipe (101-1) is arranged above the second heat dissipation pipe (101-2). The third heat dissipation pipe (101-3) is perpendicularly connected to both the first heat dissipation pipe (101-1) and the second heat dissipation pipe (101-2).
5. The heat dissipation system for the mechanical compartment of a rail vehicle according to any one of claims 1 to 4, characterized in that: The heat dissipation device (1) is installed on the roof, bottom or side wall of the rail vehicle (12).
6. The heat dissipation system for the mechanical compartment of a rail vehicle according to any one of claims 1 to 4, characterized in that: The machine room (13) adopts a closed structure.
7. The heat dissipation system for the mechanical compartment of a rail vehicle according to any one of claims 1 to 4, characterized in that: The machine room (13) is equipped with a first temperature sensor (10). The first temperature sensor (10), the first three-way valve (5), the second three-way valve (6), the first valve (7), the heat dissipation device (1), the outdoor unit (2) and the indoor unit (3) are all electrically connected to the control system (4). The control system (4) controls the opening and closing status of the first three-way valve (5), the second three-way valve (6), the first valve (7) and the outdoor unit (2) and the number of heat dissipation modules in the heat dissipation device (1) according to the temperature in the machine room (13), so that the temperature in the machine room (13) is always maintained within the corresponding threshold range.
8. The heat dissipation system for the mechanical compartment of a rail vehicle according to any one of claims 1 to 4, characterized in that: The fourth circulation pipeline (17) is equipped with a delivery pump (9), which is located between the second three-way valve (6) and the heat dissipation device (1).
9. A method for controlling heat dissipation in the mechanical compartment of a rail vehicle, characterized in that: The rail vehicle mechanical room heat dissipation system as described in any one of claims 1 to 8 includes the following steps: Step S1: Collect the temperature inside the machine room (13); Step S2: When the temperature in the machine room (13) is higher than the threshold range, open the first valve (7), indoor unit (3) and outdoor unit (2), close the second three-way valve (6), operate the first three-way valve (5) so that the refrigerant in the indoor unit (3) exchanges heat and enters the outdoor unit (2) through the first circulation pipe (14) for heat exchange. The refrigerant in the outdoor unit (2) exchanges heat and returns to the indoor unit (3) through the second circulation pipe (15), so that the temperature in the machine room (13) is always maintained within the threshold range. When the temperature in the machine room (13) is lower than the threshold range, the indoor unit (3) is turned on, the outdoor unit (2) and the first valve (7) are turned off, and the first three-way valve (5) and the second three-way valve (6) are operated so that the refrigerant in the indoor unit (3) exchanges heat and enters the heat dissipation device (1) through the third circulation pipe (16) for heat exchange. After the refrigerant in the heat dissipation device (1) exchanges heat, it returns to the indoor unit (3) through the fourth circulation pipe (17) and the second circulation pipe (15), so that the temperature in the machine room (13) is always maintained within the threshold range. When the temperature collected in the machine room (13) is within the threshold range, the indoor unit (3) and the first valve (7) are turned on, and the first three-way valve (5) and the second three-way valve (6) are operated so that the refrigerant in the indoor unit (3) exchanges heat and enters the heat dissipation device (1) through the third circulation pipe (16) for heat exchange. After the refrigerant in the heat dissipation device (1) exchanges heat, it enters the outdoor unit (2) through the fourth circulation pipe (17), the fifth circulation pipe (11) and the first circulation pipe (14), and finally returns to the indoor unit (3) through the second circulation pipe (15), so that the temperature in the machine room (13) is always maintained within the threshold range. The threshold range is set according to the operating temperature range of the machine room (13).
10. The heat dissipation control method for the mechanical compartment of a rail vehicle according to claim 9, characterized in that: In step S2, when the temperature in the machine room (13) is lower than the threshold range, the number of heat dissipation modules in the heat dissipation device (1) is adjusted as needed; when the temperature in the machine room (13) is within the threshold range, all heat dissipation modules in the heat dissipation device (1) are turned on and the outdoor unit (2) is turned off. If the temperature in the machine room (13) continues to rise, the outdoor unit (2) is turned on so that the refrigerant is further cooled by the outdoor unit (2) and then returns to the indoor unit (3), thereby keeping the temperature in the machine room (13) within the threshold range.