Electric heavy truck heat management system and method

Abstract

The application discloses an electric heavy truck heat management system and method, which comprises a heat exchange part, a switching valve, a refrigerant compressor and a containing part. The heat exchange part comprises an inner heat exchanger, an inner valve, an outer heat exchanger and a first expansion valve connected in sequence. The switching valve has two first ports and two second ports, and can control the independent communication and disconnection of each first port and each second port. The two second ports are connected to the connecting pipeline between the inner valve and the outer heat exchanger. The inlet end and the outlet end of the refrigerant compressor are respectively connected to the two first ports. The containing part has a channel for containing a power battery, which is connected to the connecting pipeline between the switching valve and the inner valve, and is connected to the connecting pipeline between the first expansion valve and the inner heat exchanger. The scheme integrates the power battery cooling and the cabin temperature adjustment together, does not need to independently set a driving device, simplifies the system components, improves the collaboration, and occupies a smaller space, facilitating the integration.

Description

Technical Field

[0001] This invention relates to the field of thermal management technology for electric heavy-duty trucks, and specifically to a thermal management system and method for electric heavy-duty trucks. Background Technology

[0002] Electric heavy-duty trucks have significant advantages over traditional heavy-duty trucks in terms of emissions, driving experience, and operating costs. However, thermal runaway caused by the accumulation of waste heat from the power battery may lead to a decrease in battery capacity and driving range, and increase the risk of fire and explosion. Therefore, cooling equipment is needed for the power battery.

[0003] CN111786055A discloses a cooling system for a power battery of a new energy vehicle, which includes at least two sets of cooling plates. Coolant piping systems are distributed on the lower side of each cooling plate. The coolant piping systems include inner cooling pipes distributed on the lower surface of the cooling plates and outer cooling pipes located outside the cooling plates. The outer cooling pipes are interconnected with the inner cooling pipes. A circulating water pump and a radiator are provided on the outer cooling pipes. A heat exchanger is provided between the outer cooling pipes of two adjacent sets of cooling plates to balance the temperature difference between the two sets of cooling plates, thereby removing the battery heat through circulating water.

[0004] However, the aforementioned patents provide an independent cooling system for the battery, using a separate circulating water pump to guide water circulation for cooling. This makes the thermal management of the vehicle's passenger compartment and the battery independent of each other, resulting in low collaboration and hindering integration. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned technical deficiencies and propose an electric heavy-duty truck thermal management system and method. This invention solves the technical problems of existing technologies that require batteries to be equipped with independent cooling systems and cooling is achieved by independently setting up circulating water pumps to guide water circulation. This results in the thermal management of the vehicle's passenger compartment and the battery being independent of each other, leading to complex components, low coordination, and large space occupation in the electric heavy-duty truck thermal management system, which is not conducive to integration.

[0006] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a thermal management system for electric heavy-duty trucks, comprising:

[0008] The heat exchange section includes an inner heat exchanger, an inner valve, an outer heat exchanger, and a first expansion valve connected in sequence from end to end;

[0009] The switching valve has two first ports and two second ports, and can control each first port to independently connect and disconnect each second port. The two second ports are connected to the connecting pipeline between the inner valve and the outer heat exchanger.

[0010] The refrigerant compressor has its inlet and outlet ends respectively connected to the two first ports; and

[0011] The accommodating part has a channel for accommodating the power battery and can control the opening and closing of the channel. The channel is connected to the connecting pipe between the switching valve and the inner valve, and to the connecting pipe between the first expansion valve and the inner heat exchanger.

[0012] In some embodiments, the receiving portion includes a receiving tube, a receiving sleeve, and a receiving valve. One end of the receiving tube is connected to a connecting pipeline between the switching valve and the inner valve, and the other end is connected to a connecting pipeline between the first expansion valve and the inner heat exchanger. The receiving sleeve is disposed on the receiving tube and is used to receive the power battery, and together with the internal cavity of the receiving tube, it forms the channel. The receiving valve is disposed on the receiving tube.

[0013] In some embodiments, the receiving tube has a first section located on the side of the receiving sleeve near the switching valve, and a second section located on the side of the receiving sleeve near the first expansion valve, wherein the receiving valve is disposed in the first section;

[0014] The electric heavy truck thermal management system also includes a bypass pipe and a bypass valve. The bypass pipe is connected to the first section, and its connection point is located between the accommodating valve and the accommodating sleeve. It also connects the switching valve and the external heat exchanger to the connecting pipeline. The bypass valve is located on the bypass pipe.

[0015] The electric heavy-duty truck thermal management system also includes a first heater, which is located in the second section.

[0016] In some embodiments, the connection point between the bypass pipe and the first segment is the first connection point;

[0017] The accommodating part further includes a first valve and a second valve. The first valve is disposed in the first section and located between the first connection and the accommodating sleeve. The second valve is disposed in the second section and located on the side of the first heater away from the accommodating sleeve.

[0018] In some embodiments, the connection point between the connecting pipe between the switching valve and the external heat exchanger and the bypass pipe is a second connection point;

[0019] The heat exchange section also includes an external valve, which is located between the second connection and the external heat exchanger.

[0020] In some embodiments, a filter dryer and a gas-liquid separator are sequentially connected to the inlet end of the refrigerant compressor along the direction close to the switching valve.

[0021] In some embodiments, the electric heavy-duty truck thermal management system further includes a heat dissipation pipe, a heat dissipation sleeve, a coolant tank, a first heat exchanger, and a pump body. The heat dissipation pipe is connected end to end. The inner cavity of the heat dissipation sleeve is used to accommodate the motor assembly and is connected to the heat dissipation pipe. The coolant tank is disposed on the heat dissipation pipe. The first heat exchanger has a heat source flow channel and a heat absorption flow channel. The heat source flow channel is connected to the heat dissipation pipe. The pump body is disposed on the heat dissipation pipe.

[0022] The heat exchange section further includes a waste heat pipe and a waste heat valve. The waste heat pipe is connected to the connecting pipe between the inner heat exchanger and the first expansion valve, and to the connecting pipe between the outer heat exchanger and the switching valve, and is connected to the heat absorption channel. The waste heat valve is located on the waste heat pipe.

[0023] In some embodiments, the electric heavy-duty truck thermal management system further includes a cooling pipe, a second heat exchanger, and two control valves. The cooling pipe has two access ends, both of which are connected to the heat dissipation pipe and located on both sides of the first heat exchanger. The second heat exchanger has a flow channel that connects to the cooling pipe. One of the two control valves is located on the cooling pipe, and the other is located on the heat dissipation pipe and between the access end and the first heat exchanger.

[0024] In some embodiments, the connection point between the connecting pipe between the switching valve and the external heat exchanger and the waste heat pipe is the third connection point, and the connection point between the connecting pipe between the internal heat exchanger and the first expansion valve and the waste heat pipe is the fourth connection point.

[0025] The waste heat valve includes a third valve, a second expansion valve, and a fourth valve. The third valve and the second expansion valve are located between the first heat exchanger and the third connection, and the second expansion valve and the fourth valve are located between the first heat exchanger and the fourth connection, and are arranged sequentially along the direction close to the fourth connection.

[0026] Furthermore, the present invention also provides a thermal management method applied to the thermal management system of an electric heavy-duty truck as described in any of the above claims, the thermal management method comprising:

[0027] The system obtains the actual temperature of the passenger compartment and the first preset temperature range of the passenger compartment, and obtains the actual temperature of the power battery and the first preset temperature range of the power battery. It also determines whether the actual temperature of the passenger compartment meets the first preset temperature range of the passenger compartment and whether the actual temperature of the power battery meets the first preset temperature range of the power battery.

[0028] If the actual temperature of the passenger compartment meets the first preset temperature range of the passenger compartment, and the actual temperature of the power battery meets the first preset temperature range of the power battery, then the receiving part is controlled to disconnect the channel, and the inner valve and the first expansion valve are controlled to open, and the switching valve is controlled to connect the inner valve to the outlet end of the refrigerant compressor, and the external heat exchanger is connected to the inlet end of the refrigerant compressor.

[0029] If the actual temperature of the power battery is greater than the first preset temperature range of the power battery, the receiving part is controlled to open the channel, the first expansion valve is controlled to open, and the switching valve is controlled to connect the channel to the inlet end of the refrigerant compressor and the external heat exchanger is connected to the outlet end of the refrigerant compressor.

[0030] Compared with existing technologies, the electric heavy-duty truck thermal management system provided by this invention uses an internal heat exchanger for temperature regulation of the driver's cabin. Since the power battery is located in the channel of the containment section, when the core temperature of the power battery is too high, the switching valve can be switched to connect the outlet end of the refrigerant compressor to the external heat exchanger and the channel of the containment section to the inlet end of the refrigerant compressor. Simultaneously, the channel is controlled to open, and the first expansion valve is also controlled to open. At this time, the high-temperature, high-pressure gaseous refrigerant output from the outlet end of the refrigerant compressor exchanges heat with the outside environment at the external heat exchanger, condenses and releases heat, and is converted into a high-temperature, high-pressure liquid refrigerant. After flowing through the first expansion valve, it is depressurized to a low-temperature, low-pressure liquid refrigerant, then flows through the channel of the containment section, where it vaporizes and absorbs heat from the power battery, thereby reducing the power battery temperature. Finally, it returns through the inlet end of the refrigerant compressor.

[0031] During this process, the internal valve can also be opened, allowing a portion of the low-temperature, low-pressure liquid refrigerant passing through the first expansion valve to flow to the internal heat exchanger, where it vaporizes and absorbs heat to lower the temperature inside the passenger compartment. Furthermore, when the channel is disconnected and the switching valve is adjusted to change the refrigerant flow direction, passenger compartment heating can be achieved, thus realizing three modes: power battery cooling, passenger compartment cooling, and heating. In this way, this solution integrates power battery cooling and passenger compartment temperature adjustment, eliminating the need for a separate drive unit, improving coordination, and facilitating integration. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the thermal management system for electric heavy-duty trucks provided in an embodiment of the present invention;

[0033] Figure 2 yes Figure 1 Schematic diagram of the heat exchange section, the housing section, and the refrigerant compressor;

[0034] Figure 3 yes Figure 2 Schematic diagram of the central accommodating section;

[0035] Figure 4 yes Figure 2 A schematic diagram of the bypass pipe and the refrigerant compressor;

[0036] Figure 5 Figure 1 A schematic diagram of the heat dissipation pipe and the waste heat pipe;

[0037] Figure 6 This is a flowchart of a thermal management method provided in an embodiment of the present invention.

[0038] Explanation of reference numerals in the attached figures:

[0039] 1. Heat exchange section; 11. Internal heat exchanger; 12. Internal valve; 13. External heat exchanger; 14. First expansion valve; 15. External valve; 16. Waste heat pipe; 161. Third connection; 162. Fourth connection; 17. Waste heat valve; 171. Third valve; 172. Second expansion valve; 173. Fourth valve; 2. Switching valve; 21. First port; 22. Second port; 3. Refrigerant compressor; 31. Inlet end; 32. Outlet end; 4. Receptacle section; 41. Receptacle pipe; 411 1. First section; 412. Second section; 42. Containing sleeve; 43. Containing valve; 44. First valve; 45. Second valve; 5. Bypass pipe; 51. Bypass valve; 52. First connection; 53. Second connection; 6. First heater; 7. Filter dryer; 8. Heat dissipation pipe; 81. Heat dissipation sleeve; 82. Coolant tank; 83. First heat exchanger; 84. Pump body; 85. Cooling pipe; 86. Second heat exchanger; 87. Cooling control valve; 88. Heat exchange control valve; 9. Gas-liquid separator. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0041] To address the technical problem of having a separate cooling system for the battery, which uses a separate circulating water pump to guide water circulation for cooling, resulting in independent thermal management of the vehicle's passenger compartment and the battery, low coordination, and difficulty in integration, this invention provides an electric heavy-duty truck thermal management system that integrates power battery cooling and passenger compartment temperature adjustment. This eliminates the need for a separate drive unit, simplifies system components, improves coordination, and occupies less space, making it easier to integrate.

[0042] It should be noted that the electric heavy-duty truck thermal management system described in this invention is used in, but not limited to, vehicles. For ease of explanation, this invention will only use the application of the electric heavy-duty truck thermal management system in vehicles as an example. The principle of the electric heavy-duty truck thermal management system applied to other types of equipment is essentially the same as that applied to vehicles, and will not be described in detail here.

[0043] Please see Figures 1 to 4 , Figures 1 to 4 This is a schematic diagram of the structure of an electric heavy-duty truck thermal management system according to an embodiment of the present invention. The electric heavy-duty truck thermal management system includes a heat exchange section 1, a switching valve 2, a refrigerant compressor 3, and a housing section 4. The heat exchange section 1 includes an inner heat exchanger 11, an inner valve 12, an outer heat exchanger 13, and a first expansion valve 14 connected in sequence. The switching valve 2 has two first ports 21 and two second ports 22, and can control each first port 21 to independently connect and disconnect each second port 22. The two second ports 22 are connected to the connecting pipeline between the inner valve 12 and the outer heat exchanger 13. The refrigerant compressor 3 has its inlet end 31 and outlet end 32 respectively connected to the two first ports 21. The housing section 4 has a channel for housing the power battery and can control the opening and closing of the channel. The channel is connected to the connecting pipeline between the switching valve 2 and the inner valve 12, and is also connected to the connecting pipeline between the first expansion valve 14 and the inner heat exchanger 11.

[0044] In the electric heavy-duty truck thermal management system provided by this invention, the internal heat exchanger 11 is used for temperature regulation of the driver's cabin. Since the power battery is located in the channel of the housing 4, when the core temperature of the power battery is too high, the switching valve 2 can be switched to connect the outlet end 32 of the refrigerant compressor 3 to the external heat exchanger 13, and the channel of the housing 4 to the inlet end 31 of the refrigerant compressor 3. At the same time, the channel is controlled to be open, and the first expansion valve 14 is controlled to open. At this time, the high-temperature and high-pressure gaseous refrigerant output from the outlet end 32 of the refrigerant compressor 3 exchanges heat with the outside at the external heat exchanger 13, condenses and releases heat, and is converted into a high-temperature and high-pressure liquid refrigerant. After flowing through the first expansion valve 14, it is depressurized into a low-temperature and low-pressure liquid refrigerant, and then flows through the channel of the housing 4. In the channel, it vaporizes and absorbs the heat of the power battery, thereby reducing the temperature of the power battery. Finally, it flows back through the inlet end 31 of the refrigerant compressor 3.

[0045] During this process, the inner valve 12 can be opened, allowing a portion of the low-temperature, low-pressure liquid refrigerant passing through the first expansion valve 14 to flow to the inner heat exchanger 11, where it vaporizes and absorbs heat to lower the temperature inside the passenger compartment. Furthermore, when the channel is disconnected and the switching valve 2 is adjusted to change the refrigerant flow direction, passenger compartment heating can be achieved, thus realizing three modes: power battery cooling, passenger compartment cooling, and heating. In this way, this solution integrates power battery cooling and passenger compartment temperature adjustment, eliminating the need for a separate drive unit, improving coordination, and facilitating integration.

[0046] It should be noted that, in one embodiment, the switching valve 2 is configured with six sets of connecting components, each set including a pipe and a valve disposed thereon, and the six pipes connect the components corresponding to the four ports in pairs. In another embodiment, the switching valve 2 is configured as two movable pipes, and valves are disposed at each port accordingly, so that the ports can be connected through the movable pipes.

[0047] In another embodiment, the switching valve 2 is configured as a four-way valve. The specific structure and principle of the four-way valve are existing technologies and will not be described in detail here. It should be understood that the outflow channel and the return channel of the switching valve 2 are isolated from each other.

[0048] Furthermore, it should be noted that the housing 4 can be configured as a pipe and valve, or as a housing and valve, or in other forms.

[0049] In one embodiment, the accommodating part 4 includes an accommodating tube 41, an accommodating sleeve 42, and an accommodating valve 43. One end of the accommodating tube 41 is connected to the connecting pipe between the switching valve 2 and the inner valve 12, and the other end is connected to the connecting pipe between the first expansion valve 14 and the inner heat exchanger 11. The accommodating sleeve 42 is connected to the accommodating tube 41 and is used to accommodate the power battery. It also forms a channel together with the internal cavity of the accommodating tube 41. The accommodating valve 43 is located in the accommodating tube 41.

[0050] In this embodiment, the power battery is placed inside the housing sleeve 42, and the low-temperature, low-pressure refrigerant flowing through the housing sleeve 42 dissipates heat from the power battery, thereby improving its heat dissipation capacity. It should be noted that in this design, the housing sleeve 42 includes an inner shell and an outer shell, with a gap between the inner shell and the outer shell to allow for refrigerant flow. The power battery is placed inside the inner shell and fitted against the outer shell.

[0051] It should be noted that in this solution, the receiving sleeve 42 has two ports, and both ports are connected to the receiving tube 41, so that the internal cavity of the receiving sleeve 42 and the internal cavity of the receiving tube 41 together form a channel.

[0052] In one embodiment, the receiving tube 41 has a first section 411 located on the side of the receiving sleeve 42 near the switching valve 2, and a second section 412 located on the side of the receiving sleeve 42 near the first expansion valve 14. The receiving valve 43 is located in the first section 411. The electric heavy-duty truck thermal management system also includes a bypass pipe 5 and a bypass valve 51. The bypass pipe 5 is connected to the first section 411, and its connection point is located between the receiving valve 43 and the receiving sleeve 42. It also connects the connecting pipe between the switching valve 2 and the external heat exchanger 13. The bypass valve 51 is located in the bypass pipe 5. The electric heavy-duty truck thermal management system also includes a first heater 6, which is located in the second section 412.

[0053] In this embodiment, when the switching valve 2 connects the outlet end 32 of the refrigerant compressor 3 to the inner valve 12 and the bypass pipe 5 connects to the inlet end 31 of the refrigerant compressor 3, the first expansion valve 14 and the containment valve 43 are closed, the bypass valve 51 and the inner valve 12 are opened, and the first heater 6 is activated. At this time, the refrigerant flows through the following path: outlet end 32 of the refrigerant compressor 3 → switching valve 2 → inner valve 12 → inner heat exchanger 11 → first heater 6 → containment shell → bypass valve 51 → switching valve 2 → inlet end 31 of the refrigerant compressor 3. Thus, the refrigerant can be heated by the first heater 6, thereby preheating the power battery and improving its operating efficiency in extremely cold environments.

[0054] It should be noted that the first heater 6 can be configured as ceramic heating, infrared radiation heating, electric heating film heating, or other heating methods. In this scheme, the first heater 6 has a heating channel, which is connected to the first section 411 to improve heating efficiency.

[0055] In one embodiment, the connection between the bypass pipe 5 and the first section 411 is the first connection 52; the accommodating part 4 also includes a first valve 44 and a second valve 45. The first valve 44 is disposed in the first section 411 and located between the first connection 52 and the accommodating sleeve 42. The second valve 45 is disposed in the second section 412 and located on the side of the first heater 6 away from the accommodating sleeve 42.

[0056] In this embodiment, a first valve 44 and a second valve 45 are provided to improve the accuracy of switching between various modes. It should be noted that in this solution, the first valve 44, the second valve 45, the bypass valve 51, and the accommodating valve 43 are all one-way valves, and the flow direction is towards the inlet end 31 of the compressor.

[0057] In one embodiment, the connection point between the connecting pipe between the switching valve 2 and the external heat exchanger 13 and the bypass pipe 5 is the second connection point 53; the heat exchange section 1 also includes an external valve 15, which is located between the second connection point 53 and the external heat exchanger 13.

[0058] In this embodiment, an external valve 15 is further provided to prevent refrigerant from flowing to the external heat exchanger 13 during the preheating of the power battery, thereby improving heat exchange efficiency. Specifically, both the internal valve 12 and the external valve 15 are two-way valves.

[0059] In one embodiment, a second heater is provided on the external heat exchanger 13 to flexibly control the temperature of the refrigerant flowing through the external heat exchanger 13, further improving the flexibility of temperature adjustment. Specifically, both the second heater and the first heater 6 are positive temperature coefficient (PTC) electric heaters.

[0060] In one embodiment, please refer to Figure 5The electric heavy-duty truck thermal management system also includes a heat dissipation pipe 8, a heat dissipation sleeve 81, a coolant tank 82, a first heat exchanger 83, and a pump body 84. The heat dissipation pipe 8 is connected end to end. The inner cavity of the heat dissipation sleeve 81 is used to accommodate the motor assembly and is connected to the heat dissipation pipe 8. The coolant tank 82 is located on the heat dissipation pipe 8. The first heat exchanger 83 has a heat source flow channel and a heat absorption flow channel. The heat source flow channel is connected to the heat dissipation pipe 8. The pump body 84 is located on the heat dissipation pipe 8. The heat exchange section 1 also includes a waste heat pipe 16 and a waste heat valve 17. The waste heat pipe 16 is connected to the connecting pipe between the inner heat exchanger 11 and the first expansion valve 14, and is connected to the connecting pipe between the outer heat exchanger 13 and the switching valve 2, and is connected to the heat absorption flow channel. The waste heat valve 17 is located on the waste heat pipe 16.

[0061] In this embodiment, waste heat recovery from the motor can be achieved. Specifically, the switching valve 2 is controlled to connect the outlet end 32 of the refrigerant compressor 3 to the inner valve 12, and the inlet end 31 of the refrigerant compressor 3 to the external radiator and waste heat pipe 16. The inner valve 12 and waste heat valve 17 are controlled to open, and the containment valve 43 and bypass valve 51 are controlled to close. The specific path of the refrigerant during waste heat recovery is as follows: outlet end 32 of refrigerant compressor 3 → switching valve 2 → inner valve 12 → inner heat exchanger 11 → heat absorption channel at least partially flowing to the first heat exchanger 83 → switching valve 2 → inlet end 31 of refrigerant compressor 3. The coolant path on the motor side is: outlet end of heat sink 81 → coolant tank 82 → heat source channel of the first heat exchanger 83 → pump body 84 → inlet end of heat sink 81.

[0062] It should be noted that the first heat exchanger 83 can be configured as a base, plate, or other structure with two flow channels. Specifically, in this design, the first heat exchanger 83 is configured as a floor-mounted heat exchanger with two flow channels. Furthermore, in this design, two heat dissipation sleeves 81 are provided, and are used sequentially along the direction close to the coolant tank 82 to house the motor and motor controller. Specifically, the heat dissipation sleeves 81 can also be configured as an outer shell and an inner shell, as detailed in the housing shell section. The coolant tank 82 contains coolant.

[0063] In one embodiment, the electric heavy-duty truck thermal management system further includes a cooling pipe 85, a second heat exchanger 86, and two control valves. The cooling pipe 85 has two access ends, both of which are connected to the heat dissipation pipe 8 and are located on both sides of the first heat exchanger 83. The second heat exchanger 86 has a flow channel that connects to the cooling pipe 85. One of the two control valves is located on the cooling pipe 85, and the other is located on the heat dissipation pipe 8 and is located between the access end and the first heat exchanger 83.

[0064] In this embodiment, the battery side has two circuits: a cooling circuit and a heat exchange circuit. For ease of description, the control valve corresponding to the second heat exchanger 86 is defined as the cooling control valve 87, and the control valve corresponding to the first heat exchanger 83 is defined as the heat exchange control valve 88. The cooling circuit on the motor side controls the cooling control valve 87 to open and the heat exchange control valve 88 to close. The coolant flow path is as follows: outlet of heat sink 81 → coolant tank 82 → cooling control valve 87 → second heat exchanger 86 → pump body 84 → inlet of heat sink 81. At this time, the second heat exchanger 86 exchanges heat with the outside to cool the coolant, ensuring that the coolant circulates to cool the motor and motor controller. The heat exchange circuit is as follows: outlet of heat sink 81 → coolant tank 82 → heat exchange control valve 88 → first heat exchanger 83 → pump body 84 → inlet of heat sink 81.

[0065] It should be noted that the second heat exchanger 86 can be a heat exchange tube with flow channels, a heat exchange base or other structures. Specifically, in this solution, the second heat exchanger 86 is the second heat exchanger.

[0066] In one embodiment, the connection point between the switching valve 2 and the external heat exchanger 13 and the waste heat pipe 16 is the third connection point 161, and the connection point between the internal heat exchanger 11 and the first expansion valve 14 and the waste heat pipe 16 is the fourth connection point 162. The waste heat valve 17 includes a third valve 171, a second expansion valve 172 and a fourth valve 173. The third valve 171 and the second expansion valve 172 are located between the first heat exchanger 83 and the third connection point 161, and the second expansion valve 172 and the fourth valve 173 are located between the first heat exchanger 83 and the fourth connection point 162, and are arranged sequentially in the direction close to the fourth connection point 162.

[0067] In this embodiment, the third valve 171, the second expansion valve 172, and the fourth valve 173 ensure efficient refrigerant circulation in the circuit while also guaranteeing stable operation of each circuit. The third valve 171 and the fourth valve 173 are one-way valves, both pointing away from the internal heat exchanger 11. It should be noted that in this invention, all valves are solenoid valves; their specific structure and principle are existing technology and will not be elaborated upon here.

[0068] In addition, in this scheme, a filter dryer 7 and a gas-liquid separator 9 are sequentially connected at the inlet end 31 of the refrigerant compressor 3 along the direction close to the switching valve 2.

[0069] In addition, the present invention also provides a thermal management method, applied to the thermal management system of the electric heavy truck as described above, including:

[0070] The system obtains the actual temperature of the passenger compartment and the first preset temperature range of the passenger compartment, as well as the actual temperature of the power battery and the first preset temperature range of the power battery. It also determines whether the actual temperature of the passenger compartment meets the first preset temperature range of the passenger compartment and whether the actual temperature of the power battery meets the first preset temperature range of the power battery.

[0071] If the actual temperature of the passenger compartment meets the first preset temperature range of the passenger compartment and the actual temperature of the power battery meets the first preset temperature range of the power battery, then the control accommodating part disconnects the channel, controls the inner valve and the first expansion valve to open, and controls the switching valve to connect the inner valve to the outlet end of the refrigerant compressor and connect the outer heat exchanger to the inlet end of the refrigerant compressor.

[0072] If the actual temperature of the power battery is greater than the first preset temperature range of the power battery, the control accommodating part is connected to the conduction channel, the first expansion valve is opened, and the switching valve is controlled to connect the channel to the inlet end of the refrigerant compressor and the external heat exchanger is connected to the outlet end of the refrigerant compressor.

[0073] In this embodiment, the actual temperature of the passenger compartment is Tcab. When Tcab ≤ 25℃, and the actual temperature of the power battery is Tbat, when -10℃ ≤ Tbat < 15℃, the valves are adjusted to control the heating of the passenger compartment. When the actual temperature of the power battery Tbat ≥ 15℃, the valves are adjusted to control the cooling of the power battery. The specific switching selection of each mode is as follows. It should be noted that the actual temperature of the motor is Tmot.

[0074] To better understand this invention, the following is combined with... Figures 1 to 6 The technical solution of the present invention will be described in detail below:

[0075] The electric heavy-duty truck thermal management system in this solution has the following nine operating modes:

[0076] ① Passenger cabin cooling mode: Open inner valve 12, outer valve 15, and first expansion valve 14; close the fourth valve 173, second valve 45, first valve 44, plenum valve 43, bypass valve 51, third valve 171, cooling control valve 87, heat exchange control valve 88, and second expansion valve 172. Connect the outlet end 32 of refrigerant compressor 3 to outer valve 15 via switching valve 2, and connect the inlet of gas-liquid separator 9 to inner valve 12. The refrigerant flow path is: outlet end 32 of refrigerant compressor 3 → switching valve 2 → outer valve 15 → outer heat exchanger 13 → first expansion valve 14 → inner heat exchanger 11 → inner valve 12 → switching valve 2 → gas-liquid separator 9 → filter dryer 7 → inlet end 31 of refrigerant compressor 3. At this time, the cooling circuit on the motor and motor controller side does not participate in the circulation.

[0077] ② Passenger cabin heating mode: Open the inner valve 12, outer valve 15, and first expansion valve 14, and close the fourth valve 173, second valve 45, first valve 44, plenum valve 43, bypass valve 51, third valve 171, cooling control valve 87, heat exchange control valve 88, and second expansion valve 172. Connect the outlet end 32 of the refrigerant compressor 3 to the inner valve 12 through the switching valve 2, and connect the inlet of the gas-liquid separator 9 to the outer valve 15. The refrigerant flow path is: outlet end 32 of refrigerant compressor 3 → switching valve 2 → inner valve 12 → inner heat exchanger 11 → first expansion valve 14 → outer heat exchanger 13 → outer valve 15 → switching valve 2 → gas-liquid separator 9 → filter dryer 7 → inlet end 31 of refrigerant compressor 3. At this time, the cooling circuit on the motor and motor controller side does not participate in the circulation.

[0078] ③ Power battery cooling mode: Open the external valve 15, the first expansion valve 14, the second valve 45, the first valve 44, and the accommodating valve 43; close the internal valve 12, the fourth valve 173, the bypass valve 51, the third valve 171, the cooling control valve 87, the heat exchange control valve 88, and the second expansion valve 172. Connect the outlet end 32 of the refrigerant compressor 3 to the external valve 15 through the switching valve 2, and connect the inlet of the gas-liquid separator 9 to the accommodating valve 43. The refrigerant flow path is: outlet end 32 of the refrigerant compressor 3 → switching valve 2 → external valve 15 → external heat exchanger 13 → first expansion valve 14 → second valve 45 → first heater 6 → power battery → first valve 44 → accommodating valve 43 → switching valve 2 → gas-liquid separator 9 → filter dryer 7 → inlet end 31 of the refrigerant compressor 3. At this time, the cooling circuit on the motor and motor controller side does not participate in the circulation, and the first heater 6 is not powered on.

[0079] ④ Power battery preheating mode: Open the inner valve 12, the second valve 45, the first valve 44, and the bypass valve 51, and close the outer valve 15, the fourth valve 173, the accommodating valve 43, the third valve 171, the cooling control valve 87, the heat exchange control valve 88, the first expansion valve 14, and the second expansion valve 172. Connect the outlet end 32 of the refrigerant compressor 3 to the inner valve 12 through the switching valve 2, and connect the inlet of the gas-liquid separator 9 to the bypass valve 51. The refrigerant flow path is: outlet end 32 of the refrigerant compressor 3 → switching valve 2 → inner valve 12 → inner heat exchanger 11 → second valve 45 → first heater 6 → power battery → first valve 44 → bypass valve 51 → switching valve 2 → gas-liquid separator 9 → filter dryer 7 → inlet end 31 of the refrigerant compressor 3. At this time, the cooling circuit on the motor and motor controller side does not participate in the circulation, and the first heater 6 is energized and participates in the operation.

[0080] ⑤ Passenger compartment and power battery cooling mode: Open the inner valve 12, outer valve 15, first expansion valve 14, second valve 45, first valve 44, and accommodating valve 43; close the second expansion valve 172, fourth valve 173, bypass valve 51, third valve 171, cooling control valve 87, and heat exchange control valve 88. Connect the outlet 32 ​​of the refrigerant compressor 3 to the outer valve 15 via the switching valve 2. Connect the inlet of the gas-liquid separator 9 to the accommodating valve 43 and the inner valve 12. The refrigerant flow path is divided into two paths: one is the passenger compartment cooling path, and the other is the power battery cooling path. The passenger compartment cooling path is: refrigerant compressor 3 outlet 32 ​​→ switching valve 2 → outer valve 15 → outer heat exchanger 13 → first expansion valve 14 → inner heat exchanger 11 → inner valve 12 → switching valve 2 → gas-liquid separator 9 → filter dryer 7 → refrigerant compressor 3 inlet 31.

[0081] The cooling path for the power battery is as follows: outlet 32 ​​of refrigerant compressor 3 → switching valve 2 → external valve 15 → external heat exchanger 13 → first expansion valve 14 → second valve 45 → first heater 6 → power battery → first valve 44 → accommodating valve 43 → switching valve 2 → gas-liquid separator 9 → filter dryer 7 → inlet 31 of refrigerant compressor 3. At this time, the cooling circuits on the motor and motor controller sides do not participate in the circulation, and the first heater 6 is not energized.

[0082] ⑥ Heating mode for passenger compartment and power battery: Open the inner valve 12, outer valve 15, first expansion valve 14, second valve 45, first valve 44, and bypass valve 51; close the second expansion valve 172, fourth valve 173, accommodating valve 43, third valve 171, cooling control valve 87, and heat exchange control valve 88; and connect the outlet end 32 of the refrigerant compressor 3 to the inner valve 12 through the switching valve 2, and connect the inlet of the gas-liquid separator 9 to the bypass valve 51 and the outer valve 15. The refrigerant flow path is divided into two paths: one is the passenger compartment heating path, and the other is the power battery heating path.

[0083] The heating path for the passenger compartment is as follows: outlet 32 ​​of refrigerant compressor 3 → switching valve 2 → inner valve 12 → inner heat exchanger 11 → first expansion valve 14 → outer heat exchanger 13 → outer valve 15 → switching valve 2 → gas-liquid separator 9 → filter dryer 7 → inlet 31 of refrigerant compressor 3.

[0084] The heating path of the power battery is as follows: outlet 32 ​​of refrigerant compressor 3 → switching valve 2 → internal valve 12 → internal heat exchanger 11 → second valve 45 → first heater 6 → power battery → first valve 44 → bypass valve 51 → switching valve 2 → gas-liquid separator 9 → filter dryer 7 → inlet 31 of refrigerant compressor 3. At this time, the cooling circuit on the motor and motor controller side does not participate in the circulation, and the first heater 6 is energized and participates in the operation.

[0085] ⑦ Passenger cabin heating and motor waste heat recovery mode: Open the inner valve 12, outer valve 15, first expansion valve 14, second expansion valve 172, fourth valve 173, third valve 171, and heat exchange control valve 88; close the second valve 45, first valve 44, accommodating valve 43, bypass valve 51, and cooling control valve 87; and connect the outlet end 32 of the refrigerant compressor 3 to the inner valve 12 and the inlet of the gas-liquid separator 9 to the outer valve 15 through the switching valve 2. The refrigerant flow path is divided into two paths: one is the passenger cabin heating path, and the other is the motor waste heat recovery path.

[0086] The heating path for the passenger compartment is as follows: outlet 32 ​​of refrigerant compressor 3 → switching valve 2 → inner valve 12 → inner heat exchanger 11 → first expansion valve 14 → outer heat exchanger 13 → outer valve 15 → switching valve 2 → gas-liquid separator 9 → filter dryer 7 → inlet 31 of refrigerant compressor 3.

[0087] The waste heat recovery path of the motor is as follows: outlet end 32 of refrigerant compressor 3 → switching valve 2 → inner valve 12 → inner heat exchanger 11 → fourth valve 173 → second expansion valve 172 → heat absorption channel of first heat exchanger 83 → third valve 171 → outer valve 15 → switching valve 2 → gas-liquid separator 9 → filter dryer 7 → inlet end 31 of refrigerant compressor 3.

[0088] At this time, the cooling circuits on the motor and motor controller sides participate in the circulation. The circulation path of the coolant is: coolant tank 82 outlet → heat exchange control valve 88 → heat source flow channel of the first heat exchanger 83 → pump body 84 → heat dissipation jacket 81 → coolant tank 82 inlet.

[0089] ⑧ Cooling mode for the cockpit, motor, and motor controller: Open the inner valve 12, outer valve 15, first expansion valve 14, and cooling control valve 87; close the fourth valve 173, second valve 45, first valve 44, accommodating valve 43, bypass valve 51, third valve 171, heat exchange control valve 88, and second expansion valve 172; and connect the outlet end 32 of the refrigerant compressor 3 to the outer valve 15 through the switching valve 2, and connect the inlet of the gas-liquid separator 9 to the inner valve 12. The refrigerant flow path is: outlet end 32 of refrigerant compressor 3 → switching valve 2 → outer valve 15 → outer heat exchanger 13 → first expansion valve 14 → inner heat exchanger 11 → inner valve 12 → switching valve 2 → gas-liquid separator 9 → filter dryer 7 → inlet end 31 of refrigerant compressor 3.

[0090] At this time, the cooling circuits on the motor and motor controller sides participate in the circulation. The circulation path of the coolant is: coolant tank 82 outlet → cooling control valve 87 → second heat exchanger 86 → pump body 84 → heat dissipation jacket 81 → coolant tank 82 inlet.

[0091] ⑨ Cooling mode for the passenger compartment, power battery, motor, and motor controller: Open the inner valve 12, outer valve 15, first expansion valve 14, second valve 45, first valve 44, containment valve 43, and cooling control valve 87; close the fourth valve 173, bypass valve 51, third valve 171, heat exchange control valve 88, and second expansion valve 172; and connect the outlet end 32 of the refrigerant compressor 3 to the outer valve 15 through the switching valve 2, and connect the inlet of the gas-liquid separator 9 to the inner valve 12. The refrigerant flow path is divided into two paths: one is the passenger compartment cooling path, and the other is the power battery cooling path.

[0092] The cooling path for the passenger cabin is as follows: outlet 32 ​​of refrigerant compressor 3 → switching valve 2 → external valve 15 → external heat exchanger 13 → first expansion valve 14 → internal heat exchanger 11 → internal valve 12 → switching valve 2 → gas-liquid separator 9 → filter dryer 7 → inlet 31 of refrigerant compressor 3.

[0093] The cooling path of the power battery is as follows: outlet end 32 of refrigerant compressor 3 → switching valve 2 → external valve 15 → external heat exchanger 13 → first expansion valve 14 → second valve 45 → first heater 6 → power battery → first valve 44 → accommodating valve 43 → switching valve 2 → gas-liquid separator 9 → filter dryer 7 → inlet end 31 of refrigerant compressor 3.

[0094] At this time, the cooling circuits on the motor and motor controller sides participate in the circulation. The circulation path of the coolant is: coolant tank 82 → cooling control valve 87 → second heat exchanger 86 → pump body 84 → motor → motor controller → coolant tank 82. The first heater 6 is not powered on.

[0095] The specific control methods for the above nine working modes include:

[0096] Power battery thermal management control method: Obtain the operating temperature of the power battery; determine if the operating temperature is less than -10℃; if yes, activate the power battery preheating mode; if no, further determine if the operating temperature is less than 0℃. If yes, activate the passenger compartment heating and motor waste heat recovery modes simultaneously with the power battery preheating mode; if no, further determine if the operating temperature is less than 15℃. If yes, deactivate the power battery preheating mode and activate the passenger compartment heating / motor waste heat recovery mode; if no, further determine if the operating temperature is less than 45℃. If yes, deactivate the eight modes except for the power battery cooling mode; if no, keep the power battery cooling mode on. Repeatedly determine if the operating temperature is less than -10℃.

[0097] Passenger cabin thermal management control method: Obtain the operating temperature of the passenger cabin; determine if the operating temperature is less than 15℃; if yes, activate the passenger cabin heating and motor waste heat recovery mode, and simultaneously power on the second heater 7; if no, further determine if the operating temperature is less than 20℃. If yes, keep the passenger cabin heating and motor waste heat recovery mode on, and disconnect the power to the second heater 7 to stop heating; if no, further determine if the operating temperature is greater than 25℃. If yes, activate the passenger cabin cooling mode; if no, activate the passenger cabin heating mode, and shut off the heat pump waste heat recovery loop. Repeat the process of determining if the operating temperature is less than 15℃.

[0098] Thermal management control method for motor and motor controller: Obtain the operating temperature of the motor and motor controller; determine whether the operating temperature is less than 60℃; if yes, turn off the nine operating modes; if no, turn on the cooling mode for the passenger cabin and the motor and motor controller. Repeatedly determine whether the operating temperature is less than 60℃.

[0099] The present invention has the following beneficial effects:

[0100] 1. The electric heavy-duty truck thermal management system provided by this invention uses refrigerant instead of traditional coolant to directly heat or cool the power battery, eliminating the need for existing liquid cooling systems, reducing the overall weight of the electric heavy-duty truck, and also saving energy consumption. The heat dissipation and preheating requirements of the power battery in electric heavy-duty trucks are much greater than those in pure electric small and medium-sized cars. The latent heat of cooling of refrigerant is greater than that of coolant, and its heat absorption capacity per unit mass is strong, resulting in a faster cooling rate, making it more suitable for the heavy-load, high-power operating conditions of electric heavy-duty trucks. Compared to the secondary cooling of coolant, the refrigerant directly contacts the liquid cooling plate of the power battery, which reduces thermal resistance and improves temperature uniformity.

[0101] 2. The nine working modes provided by this invention can realize the following: cooling and heating of the passenger cabin, cooling and preheating of the power battery, simultaneous cooling of the passenger cabin and the power battery, simultaneous heating of the passenger cabin and the power battery, simultaneous heating of the passenger cabin and the motor waste heat recovery, simultaneous cooling of the passenger cabin, the motor, and the motor controller, and simultaneous cooling of the passenger cabin, the power battery, the motor, and the motor controller.

[0102] 3. The electric heavy-duty truck thermal management system provided by this invention can achieve refined management and control of the electric heavy-duty truck thermal management system, including the cab, power battery, motor, and motor controller, by controlling the switching of one-way solenoid valves, two-way solenoid valves, and electronic expansion valves. The thermal regulation is centralized, the waste heat recovery of the motor effectively extends and improves the system efficiency, reduces the energy consumption of the power battery, improves the comfort of the cab, and increases the range and safety of electric heavy-duty trucks in winter operating conditions.

[0103] 4. The thermal management method provided by this invention acquires the operating temperatures of the driver's cabin, power battery, motor, and motor controller in real time. In winter, when the electric heavy truck is running stably and the evaporator is frosted, the first heater 6 and the second heater 7 are used to preheat the system. When the power battery temperature exceeds 0°C and the driver's cabin temperature exceeds 15°C, the PTC electric heating is stopped to save energy. At this time, the heating demand of the power battery and driver's cabin is reduced, and the waste heat from the motor can not only continue to heat the power battery and driver's cabin, improving the comfort of the driver's cabin, but also save power battery energy consumption and increase the driving range of the electric heavy truck.

[0104] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A thermal management system for electric heavy-duty trucks, characterized in that, include: The heat exchange section includes an inner heat exchanger, an inner valve, an outer heat exchanger, and a first expansion valve connected in sequence from end to end. The switching valve has two first ports and two second ports, and can control each first port to independently connect and disconnect each second port. The two second ports are connected to the connecting pipeline between the inner valve and the outer heat exchanger. The refrigerant compressor has its inlet and outlet ends respectively connected to the two first ports; and The accommodating part has a channel for accommodating the power battery and can control the opening and closing of the channel. The channel is connected to the connecting pipe between the switching valve and the inner valve, and is also connected to the connecting pipe between the first expansion valve and the inner heat exchanger. The accommodating part includes an accommodating tube, an accommodating sleeve, and an accommodating valve. One end of the accommodating tube is connected to the connecting pipe between the switching valve and the inner valve, and the other end is connected to the connecting pipe between the first expansion valve and the inner heat exchanger. The accommodating sleeve is disposed on the accommodating tube and is used to accommodate the power battery. It together with the internal cavity of the accommodating tube forms the channel. The accommodating valve is disposed on the accommodating tube. The receiving tube has a first section located on the side of the receiving sleeve near the switching valve, and a second section located on the side of the receiving sleeve near the first expansion valve, and the receiving valve is located in the first section; The electric heavy truck thermal management system also includes a bypass pipe and a bypass valve. The bypass pipe is connected to the first section, and its connection point is located between the accommodating valve and the accommodating sleeve. It also connects the switching valve and the external heat exchanger to the connecting pipeline. The bypass valve is located on the bypass pipe. The electric heavy-duty truck thermal management system also includes a first heater, which is located in the second section; The electric heavy-duty truck thermal management system further includes a heat dissipation pipe, a heat dissipation sleeve, a coolant tank, a first heat exchanger and a pump body. The heat dissipation pipe is connected end to end. The inner cavity of the heat dissipation sleeve is used to accommodate the motor assembly and is connected to the heat dissipation pipe. The coolant tank is located on the heat dissipation pipe. The first heat exchanger has a heat source flow channel and a heat absorption flow channel. The heat source flow channel is connected to the heat dissipation pipe. The pump body is located on the heat dissipation pipe. The heat exchange section further includes a waste heat pipe and a waste heat valve. The waste heat pipe is connected to the connecting pipe between the inner heat exchanger and the first expansion valve, and to the connecting pipe between the outer heat exchanger and the switching valve, and is connected to the heat absorption channel. The waste heat valve is located on the waste heat pipe. The electric heavy-duty truck thermal management system further includes a cooling pipe, a second heat exchanger, and two control valves. The cooling pipe has two access ends, both of which are connected to the heat dissipation pipe and are located on both sides of the first heat exchanger. The second heat exchanger has a flow channel that connects to the cooling pipe. One of the two control valves is located on the cooling pipe, and the other is located on the heat dissipation pipe and between the access end and the first heat exchanger.

2. The electric heavy-duty truck thermal management system according to claim 1, characterized in that, The connection point between the bypass pipe and the first section is the first connection point; The accommodating part further includes a first valve and a second valve. The first valve is disposed in the first section and located between the first connection and the accommodating sleeve. The second valve is disposed in the second section and located on the side of the first heater away from the accommodating sleeve.

3. The electric heavy-duty truck thermal management system according to claim 1, characterized in that, The connection point between the connecting pipe between the switching valve and the external heat exchanger and the bypass pipe is the second connection point; The heat exchange section also includes an external valve, which is located between the second connection and the external heat exchanger.

4. The electric heavy-duty truck thermal management system according to claim 1, characterized in that, The inlet end of the refrigerant compressor is connected in sequence to a filter dryer and a gas-liquid separator along the direction close to the switching valve.

5. The electric heavy-duty truck thermal management system according to claim 1, characterized in that, The connection point between the connecting pipe between the switching valve and the external heat exchanger and the waste heat pipe is the third connection point, and the connection point between the connecting pipe between the internal heat exchanger and the first expansion valve and the waste heat pipe is the fourth connection point. The waste heat valve includes a third valve, a second expansion valve, and a fourth valve. The third valve and the second expansion valve are located between the first heat exchanger and the third connection, and the second expansion valve and the fourth valve are located between the first heat exchanger and the fourth connection, and are arranged sequentially along the direction close to the fourth connection.

6. A thermal management method for electric heavy-duty trucks, applied to the thermal management system for electric heavy-duty trucks as described in any one of claims 1-5, characterized in that, include; The system obtains the actual temperature of the passenger compartment and the first preset temperature range of the passenger compartment, and obtains the actual temperature of the power battery and the first preset temperature range of the power battery. It also determines whether the actual temperature of the passenger compartment meets the first preset temperature range of the passenger compartment and whether the actual temperature of the power battery meets the first preset temperature range of the power battery. If the actual temperature of the passenger compartment meets the first preset temperature range of the passenger compartment, and the actual temperature of the power battery meets the first preset temperature range of the power battery, then the receiving part is controlled to disconnect the channel, and the inner valve and the first expansion valve are controlled to open, and the switching valve is controlled to connect the inner valve to the outlet end of the refrigerant compressor, and the external heat exchanger is connected to the inlet end of the refrigerant compressor. If the actual temperature of the power battery is greater than the first preset temperature range of the power battery, the receiving part is controlled to open the channel, the first expansion valve is controlled to open, and the switching valve is controlled to connect the channel to the inlet end of the refrigerant compressor and the external heat exchanger is connected to the outlet end of the refrigerant compressor.

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