Passenger car comprehensive thermal management system and control method

Abstract

According to the passenger car comprehensive heat management system and the control method, by arranging two sets of circulation systems, a water circulation system and a refrigerant circulation system are isolated, and heat exchange is conducted through a first heat exchanger; the refrigerant pipe is arranged outside the passenger compartment of the passenger car, water circulates in the water pipe, and refrigerant circulates in the refrigerant pipe, so that the safety risk of the combustible refrigerant is transferred to the outside of the passenger compartment, and the system safety is improved. The water circulation system comprises a bottom plate water coil pipe, a passenger area water coil pipe, a defroster water coil pipe and a battery cooling pipeline, pipelines needing refrigeration or heating can be selectively started according to requirements, the whole vehicle heat management coordination is high, and almost all scene requirements of an existing electric motor coach are met.

Description

Technical Field

[0001] This application belongs to the field of vehicle air conditioning technology, and in particular relates to a comprehensive thermal management system and control method for buses. Background Technology

[0002] With increasingly stringent environmental protection requirements, Europe and North America have set stricter requirements for refrigerant GWP. Among existing technologies, R290 is an excellent refrigerant and a natural refrigerant that is harmless to the environment. However, its flammability poses certain safety hazards.

[0003] The existing thermal management system for buses is relatively simple and cannot fully coordinate the thermal management of the entire vehicle. It is not perfect in terms of energy saving, cooling and heating performance. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a comprehensive thermal management system and control method for buses in order to solve at least one of the above-mentioned problems in the prior art.

[0005] The technical solution adopted by this invention to solve its technical problem is:

[0006] A comprehensive thermal management system for buses, comprising:

[0007] A water circulation system, comprising water pipes and floor water coils, passenger area water coils, defrost water coils, and battery cooling pipes connected to the water pipes; the floor water coils are arranged on the floor of the bus, the passenger area water coils are arranged in the passenger area of ​​the bus, the defrost water coils are arranged at the defrost unit of the bus, and the battery cooling pipes are arranged at the battery of the bus;

[0008] A refrigerant circulation system, the refrigerant circulation system including a refrigerant pipe and a compressor and a condenser connected through the refrigerant pipe;

[0009] The first heat exchanger is connected to the water pipe and the refrigerant pipe, and is used to enable the water circulation system to exchange heat with the refrigerant circulation system through heat exchange between the medium in the water pipe and the medium in the refrigerant pipe.

[0010] A valve assembly is used to selectively open, close, or regulate the flow rate of one or more of the pipelines containing the floor water coil, the passenger area water coil, the defrost water coil, and the battery cooling pipeline;

[0011] The refrigerant pipes are arranged outside the passenger compartment of the bus, water flows through the water pipes, and refrigerant flows through the refrigerant pipes.

[0012] Preferably, in the bus integrated thermal management system of the present invention, the water circulation system further includes a PTC heater, which is connected to the water pipe and used to heat the water flowing in the water pipe.

[0013] Preferably, in the integrated thermal management system for buses of the present invention, the water circulation system further includes:

[0014] The first cooling fan is used to accelerate the heat dissipation of the base plate water coil;

[0015] The second cooling fan is used to accelerate the heat dissipation of the defrost coil.

[0016] The third cooling fan is used to accelerate the cooling of the water coils in the passenger area.

[0017] Preferably, in the integrated thermal management system for buses of the present invention, the water circulation system further includes:

[0018] An expansion tank, connected to the water pipe, is used to replenish the water pipe with flowing water and to control the water pressure.

[0019] A variable frequency water pump is connected to the water pipe and is used to pump water in the water pipe and regulate the flow rate.

[0020] Preferably, in the integrated thermal management system for buses of the present invention, the water pipes include: a main line, a first branch line, a second branch line, a third branch line, and a fourth branch line;

[0021] The floor water coil is located in the first branch, the passenger area water coil is located in the second branch, and the defrost water coil is located in the third branch. The first branch, the second branch, and the third branch are arranged in parallel.

[0022] The battery cooling pipe is located in the fourth branch, which is connected in series with the first branch, the second branch, and the third branch.

[0023] Preferably, in the bus integrated thermal management system of the present invention, the valve assembly includes a three-way proportional valve, the main line is connected to the fourth branch line through the three-way proportional valve, and the three-way proportional valve is used to distribute the flow between the main line and the fourth branch line.

[0024] Preferably, in the bus integrated thermal management system of the present invention, the refrigerant circulation system further includes a four-way reversing valve, which is connected to the four ports of the refrigerant pipe so that the refrigerant flow direction in the refrigerant pipe can be switched.

[0025] Preferably, in the bus integrated thermal management system of the present invention, the refrigerant circulation system further includes a jet enthalpy enhancement unit, which is connected to the refrigerant pipe and the compressor.

[0026] A method for integrated thermal management and control of a passenger bus, employing the aforementioned integrated thermal management system, includes the following steps:

[0027] The refrigerant circulation system can be used for cooling or heating. Based on the cooling or heating needs of the bus floor, passenger area, defroster, or battery, one or more of the pipes containing the floor water coil, passenger area water coil, defroster water coil, and battery cooling pipe can be selectively opened, closed, or have their flow rates adjusted.

[0028] Preferably, the integrated thermal management control method for passenger vehicles of the present invention includes the following steps:

[0029] When there is only a need for battery cooling and the ambient temperature is not lower than the preset value, the compressor operates at a preset fixed speed.

[0030] When only battery cooling is required and the ambient temperature is below a preset value, the compressor is turned off, and a cooling fan is used to accelerate the cooling of the passenger area water coil.

[0031] The beneficial effects of this invention are: Two circulation systems are arranged, isolating the water circulation system from the refrigerant circulation system and exchanging heat through a first heat exchanger; refrigerant pipes are arranged outside the passenger compartment of the bus, with water flowing in the water pipes and refrigerant flowing in the refrigerant pipes, thus transferring the safety risk of flammable refrigerant to the outside of the passenger compartment and improving system safety. The water circulation system includes floor water coils, passenger area water coils, defrost water coils, and battery cooling pipes. Pipes requiring cooling or heating can be selectively activated as needed, resulting in strong overall vehicle thermal management coordination and covering almost all scenario requirements of current electric buses. Attached Figure Description

[0032] The technical solution of this application will be further described below with reference to the accompanying drawings and embodiments.

[0033] Figure 1 This is a schematic diagram of the structure of the integrated thermal management system for buses according to an embodiment of this application;

[0034] Figure 2 This is a schematic diagram of the water circulation system structure according to an embodiment of this application;

[0035] Figure 3 This is a schematic diagram of the refrigerant circulation system according to an embodiment of this application.

[0036] The attached figures are labeled as follows:

[0037] 10. Heater; 11. Water pipes; 12. Floor water coil; 13. Passenger area water coil;

[0038] 14. Defrost water coil; 15. Piping; 16. First cooling fan;

[0039] 17. Second cooling fan; 18. Third cooling fan; 21. Refrigerant pipe;

[0040] 110. Main road; 111. First branch road; 112. Second branch road; 113. Third branch road;

[0041] 114. Fourth branch; 191. Expansion tank; 192. Variable frequency pump;

[0042] 22. Compressor; 23. Condenser; 24. Four-way reversing valve;

[0043] 25. Jet enthalpy enhancement unit; 251. Main electronic expansion valve; 252. Auxiliary electronic expansion valve;

[0044] 253. Economizer heat exchange plate; 254. One-way valve assembly;

[0045] 26. Fourth cooling fan;

[0046] 3. First heat exchanger. Detailed Implementation

[0047] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0048] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, 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, and therefore should not be construed as limiting the scope of protection of this application. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0049] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art will understand the specific meaning of the above terms in this application based on the specific circumstances.

[0050] The technical solution of this application will now be described in detail with reference to the accompanying drawings and embodiments.

[0051] This embodiment provides a comprehensive thermal management system for buses, such as... Figure 1 As shown, it includes: a water circulation system, a refrigerant circulation system, a valve assembly, and a first heat exchanger 3.

[0052] The water circulation system includes a water pipe 11 and a floor water coil 12, a passenger area water coil 13, a defrost water coil 14, and a battery cooling pipe 15 connected through the water pipe 11. The floor water coil 12 is located on the floor of the bus, the passenger area water coil 13 is located in the passenger area of ​​the bus, the defrost water coil 14 is located at the defrost unit of the bus, and the battery cooling pipe 15 is located at the battery of the bus.

[0053] The refrigerant circulation system includes a refrigerant pipe 21 and a compressor 22 and a condenser 23 connected through the refrigerant pipe 21.

[0054] The first heat exchanger 3 is connected to the water pipe 11 and the refrigerant pipe 21, and is used to exchange heat between the water circulation system and the refrigerant circulation system through the heat exchange between the medium in the water pipe 11 and the medium in the refrigerant pipe 21.

[0055] Refrigerant pipe 21 is arranged outside the passenger compartment of the bus, water flows in water pipe 11, and refrigerant flows in refrigerant pipe 21;

[0056] The valve assembly is used to selectively open, close, or regulate the flow rate of one or more of the pipelines containing the floor water coil 12, passenger area water coil 13, defrost water coil 14, and battery cooling pipe 15.

[0057] The integrated thermal management system for buses provided in this embodiment features two circulation systems. The water circulation system is isolated from the refrigerant circulation system, and heat exchange occurs through the first heat exchanger 3. Refrigerant pipes 21 are located outside the passenger compartment of the bus. Water flows through water pipes 11, and refrigerant flows through refrigerant pipes 21, transferring the safety risk of flammable refrigerant to the outside of the passenger compartment and improving system safety. The water circulation system includes a floor water coil 12, a passenger area water coil 13, a defroster water coil 14, and a battery cooling pipe 15. Pipes requiring cooling or heating can be selectively activated as needed. The overall vehicle thermal management is highly coordinated, covering almost all scenario requirements of current electric buses.

[0058] The scenarios that the bus integrated thermal management system of this embodiment can theoretically realize include: passenger compartment cooling and heating; front defrost unit cooling and heating; floor heating; battery-side separate cooling and heating; and battery-side cooling when the passenger compartment is cooling and heating.

[0059] In an alternative embodiment, such as Figure 1 As shown, the water circulation system also includes a PTC heater 10, which is connected to the water pipe 11 and used to heat the water flowing in the water pipe 11. The PTC heater 10 can realize electric auxiliary heating of the water circulation system, as well as heating when the battery needs heating alone, enhancing the system's heating flexibility.

[0060] In an alternative embodiment, such as Figure 1 As shown, the water circulation system also includes a first cooling fan 16, a second cooling fan 17, and a third cooling fan 18. The first cooling fan 16 is used to accelerate the heat dissipation of the floor water coil 12; the second cooling fan 17 is used to accelerate the heat dissipation of the defrost water coil 14; and the third cooling fan 18 is used to accelerate the heat dissipation of the passenger area water coil 13. In this embodiment, one or more of the first cooling fan 16, the second cooling fan 17, and the third cooling fan 18 can be selectively activated according to different cooling or heating needs to accelerate defrosting, accelerate floor heating, or accelerate passenger area cooling or heating.

[0061] In an alternative embodiment, such as Figure 1 As shown, the water circulation system also includes an expansion tank 191, which is connected to the water pipe 11. The expansion tank 191 is used to replenish the water pipe 11 with circulating water and control the water pressure. It can also be used for filling liquid and venting.

[0062] The water circulation system also includes a variable frequency water pump 192, which is connected to the water pipe 11 and is used to pump water in the water pipe 11 and regulate the flow rate. The variable frequency water pump 192 is the power source for water circulation in the water circulation system. The target parameter that can be correlated with its control is the pressure difference between the inlet and outlet of the variable frequency water pump 192. That is, by preset a target pressure difference that adapts to the system resistance, the actual pressure difference deviation is detected in real time. By using variable frequency speed regulation, the changes in pipeline resistance are dynamically offset, which not only meets the flow requirements of the terminal equipment, but also avoids energy waste in the case of large flow and low load.

[0063] In an alternative embodiment, such as Figure 2 As shown, water pipe 11 includes: main pipe 110, first branch pipe 111, second branch pipe 112, third branch pipe 113, and fourth branch pipe 114. The floor water coil 12 is located in the first branch pipe 111, the passenger area water coil 13 is located in the second branch pipe 112, and the defrost water coil 14 is located in the third branch pipe 113. The first branch pipe 111, the second branch pipe 112, and the third branch pipe 113 are arranged in parallel. The battery cooling pipe 15 is located in the fourth branch pipe 114, and the fourth branch pipe 114 is arranged in series with the first branch pipe 111, the second branch pipe 112, and the third branch pipe 113.

[0064] This piping layout allows the battery cooling to be linked to the heating of the floor, passenger area, or defroster at any time, making full use of the battery's heat generation characteristics when powered on, achieving full energy coordination within the system, and reducing energy consumption.

[0065] In an alternative embodiment, such as Figure 2 As shown, the valve assembly includes a three-way proportional valve. The main line 110 is connected to the fourth branch line 114 via the three-way proportional valve. The three-way proportional valve is used to distribute the flow between the main line 110 and the fourth branch line 114. In this embodiment, the core function of connecting the main line 110 to the branch line via the three-way proportional valve is precise flow distribution and dynamic load adaptation. Through the continuously adjustable characteristics of the proportional valve, precise control of flow and pressure between the main line and the branch line is achieved, taking into account both system stability and energy saving. The target parameter that can be correlated with its control is the temperature difference between the inlet and outlet water of the battery cooling pipe 15. As the temperature difference increases, the flow rate allocated to the battery becomes more adaptive.

[0066] In an alternative embodiment, such as Figure 3 As shown, the refrigerant circulation system also includes a four-way reversing valve 24, which connects to the four ports of the refrigerant pipe 21 to allow the refrigerant flow direction in the refrigerant pipe 21 to be switched. This four-way reversing valve 24 allows for on-the-fly switching between cooling and heating modes.

[0067] The changes and flow of refrigerant during refrigeration are as follows: Compressor 22 (discharges high-pressure, high-temperature gaseous refrigerant) → Four-way reversing valve 24 (refrigeration position) → Condenser 23 (liquefies and releases heat, becoming high-pressure liquid) → First heat exchanger 3 (exchanges heat with the water circulation system, evaporates and absorbs heat, becoming low-pressure gas) → Four-way reversing valve 24 (return gas position) → Compressor 22 (suction circulation);

[0068] The changes and flow of the refrigerant during heating are as follows:

[0069] Compressor 22 (discharges high-pressure, high-temperature gaseous refrigerant) → Four-way reversing valve 24 (heating position) → First heat exchanger 3 (exchanges heat with the water circulation system, liquefies and releases heat for heating, becoming high-pressure liquid) → Condenser 23 (evaporates and absorbs heat, becoming low-pressure gaseous) → Four-way reversing valve 24 (return gas position) → Compressor 22 (suction circulation).

[0070] In an alternative embodiment, such as Figure 1 As shown, the refrigerant cycle system also includes a vapor injection enthalpy enhancement unit 25, which is connected to the refrigerant pipe 21 and the compressor 22. By adding the vapor injection enthalpy enhancement unit 25, the refrigerant cycle system not only significantly improves heating capacity and energy efficiency during low-temperature heating, but also increases subcooling during cooling, thereby improving cooling capacity and energy efficiency.

[0071] In an alternative embodiment, such as Figure 3As shown, the vapor injection enthalpy enhancement unit 25 includes a main electronic expansion valve 251 (EEV), an auxiliary electronic expansion valve 252 (EEV), an economizer heat exchange plate 253, and a one-way valve group 254. The main electronic expansion valve 251 precisely controls the refrigerant flow rate and throttling pressure reduction effect in the refrigerant pipe 21, throttling the high-pressure liquid refrigerant output from the condenser 23 into a low-pressure, low-temperature gas-liquid mixture to meet the heat exchange requirements of the first heat exchanger 3. The auxiliary electronic expansion valve 252 regulates the refrigerant flow rate in the auxiliary circuit (gas injection circuit), cooperating with the economizer to complete the intermediate gas injection process, achieving the vapor injection enthalpy enhancement effect, while controlling the superheat of the compressor 22 discharge to ensure stable compression.

[0072] The one-way valve assembly 254 includes 2 to 4 one-way valves (configured according to system complexity). Through the reverse cut-off characteristic of the built-in one-way valves, the refrigerant flow direction of the gas injection circuit is automatically switched. Without additional manual adjustment, it can stably carry out jet enthalpy enhancement under both cooling and heating conditions, significantly improving the system's energy efficiency and operational stability across the entire temperature range.

[0073] In an alternative embodiment, such as Figure 1 As shown, the first branch 111 is equipped with an electric ball valve to control the water flow rate, which can be automatically adjusted according to the temperature difference between the inlet and outlet water.

[0074] In an alternative embodiment, such as Figure 1 As shown, the valve assembly also includes an electric ball valve. The second branch 112, the third branch 113, or the jet enthalpy enhancement unit 25 are equipped with electric ball valves to achieve flow control.

[0075] In this embodiment, R290 can be selected as the refrigerant. All refrigerant-connecting components are located on the exterior of the vehicle, and the electrical components have an IP55 or higher rating to prevent safety risks in case of leakage. The condenser 23 can be equipped with a fourth cooling fan 26 to enhance heat exchange performance.

[0076] This embodiment provides a comprehensive thermal management control method for buses, employing the aforementioned comprehensive thermal management system for buses, and includes the following steps:

[0077] The refrigerant circulation system can be used for cooling or heating. Depending on the cooling or heating needs of the bus floor, passenger area, defroster, or battery, one or more of the pipes containing the floor water coil 12, passenger area water coil 13, defroster water coil 14, and battery cooling pipe 15 can be selectively opened, closed, or have their flow rates adjusted.

[0078] The bus integrated thermal management control method of this embodiment can comprehensively manage the cooling and heating needs of various areas of the vehicle by adjusting the flow of multiple pipes, making energy consumption more reasonable.

[0079] Preferably, the bus integrated thermal management control method of this embodiment includes the following steps:

[0080] When there is only a need for battery cooling and the ambient temperature is not lower than the preset value (e.g., 10°C), the compressor 22 operates at a preset fixed speed.

[0081] When only battery cooling is required and the ambient temperature is below a preset value, compressor 22 shuts off, and a cooling fan is used to accelerate heat dissipation from the passenger area water coil 13. This method can significantly save energy under specific operating conditions.

[0082] Based on the above-described preferred embodiments according to this application, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this application. The technical scope of this application is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A comprehensive thermal management system for a passenger vehicle, characterized by, The application relates to a refrigeration system for a passenger car, which comprises: a water circulation system, which comprises a water pipe (11) and a bottom plate water coil (12), a passenger area water coil (13), a defroster water coil (14) and a battery cooling pipe (15) connected by the water pipe (11); the bottom plate water coil (12) is arranged at the bottom plate of the passenger car, the passenger area water coil (13) is arranged at the passenger area of the passenger car, the defroster water coil (14) is arranged at the defroster of the passenger car, and the battery cooling pipe (15) is arranged at the battery of the passenger car; a refrigerant circulation system, which comprises a refrigerant pipe (21) and a compressor (22) and a condenser (23) connected by the refrigerant pipe (21); a first heat exchanger (3) connected with the water pipe (11) and the refrigerant pipe (21), which is used for heat exchange between the medium in the water pipe (11) and the medium in the refrigerant pipe (21) to realize heat exchange between the water circulation system and the refrigerant circulation system; a valve assembly, which is used for selectively opening, closing or adjusting the flow of one or more pipes in which the bottom plate water coil (12), the passenger area water coil (13), the defroster water coil (14) and the battery cooling pipe (15) are arranged; the refrigerant pipe (21) is arranged outside the passenger cabin of the passenger car, water flows in the water pipe (11), and refrigerant flows in the refrigerant pipe (21).

2. The integrated thermal management system for a passenger vehicle of claim 1, wherein, The water circulation system further comprises a PTC heater (10) connected with the water pipe (11) and used for heating the water flowing in the water pipe (11).

3. The integrated thermal management system for a passenger vehicle of claim 1, wherein, The water circulation system further comprises: a first heat dissipation fan (16) used for accelerating heat dissipation of the bottom plate water coil (12); a second heat dissipation fan (17) used for accelerating heat dissipation of the defroster water coil (14); a third heat dissipation fan (18) used for accelerating heat dissipation of the passenger area water coil (13).

4. The integrated thermal management system for a passenger vehicle of any of claims 1-3, wherein, The water circulation system further comprises: an expansion water tank (191) connected with the water pipe (11) and used for supplementing water flowing in the water pipe (11) and controlling water pressure; a variable frequency water pump (192) connected with the water pipe (11) and used for pumping water in the water pipe (11) and adjusting flow.

5. The integrated thermal management system for a passenger vehicle of any of claims 1-3, wherein, The water pipe (11) comprises a main branch (110), a first branch (111), a second branch (112), a third branch (113) and a fourth branch (114); the bottom plate water coil (12) is arranged in the first branch (111), the passenger area water coil (13) is arranged in the second branch (112), the defroster water coil (14) is arranged in the third branch (113), and the first branch (111), the second branch (112) and the third branch (113) are arranged in parallel; the battery cooling pipe (15) is arranged in the fourth branch (114), and the fourth branch (114) is arranged in series with the first branch (111), the second branch (112) and the third branch (113).

6. The integrated thermal management system for a passenger vehicle of claim 5, wherein, The valve assembly includes a three-way proportional valve, the main line (110) is connected with the fourth branch line (114) through the three-way proportional valve, and the three-way proportional valve is used for distributing the flow between the main line (110) and the fourth branch line (114).

7. The integrated thermal management system for a passenger vehicle of any one of claims 1-3, wherein, The refrigerant circulation system further comprises a four-way reversing valve (24) connected with four ports of the refrigerant pipe (21) to enable the flow direction of the refrigerant in the refrigerant pipe (21) to be switched.

8. The integrated thermal management system for a passenger vehicle of any one of claims 1-3, wherein, The refrigerant circulation system further comprises a jet augmenting enthalpy unit (25) connected with the refrigerant pipe (21) and the compressor (22).

9. A method of integrated thermal management control of a passenger vehicle, characterized by, The passenger car comprehensive thermal management system according to any one of claims 1-8 comprises the following steps: Refrigeration or heating is performed by the refrigerant circulation system, and according to the refrigeration or heating requirements of the passenger car floor, the passenger area, the defroster or the battery, one or more of the floor water coil (12), the passenger area water coil (13), the defroster water coil (14) and the battery cooling pipe (15) are selectively opened, closed or flow-regulated.

10. The passenger vehicle integrated thermal management control method of claim 9, wherein, The method comprises the following steps: When only the battery refrigeration requirement exists and the ambient temperature is not lower than a preset value, the compressor (22) is operated at a preset fixed rotating speed; When only the battery refrigeration requirement exists and the ambient temperature is lower than the preset value, the compressor (22) is turned off, and a cooling fan is used to accelerate the heat dissipation of the passenger area water coil (13).

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