A CO2 indirect heat pump system and an electric commercial vehicle

Abstract

The application discloses a CO2 indirect type heat pump system and an electric commercial vehicle, the system comprising a battery heat pump system and a cab heat pump system independent of a refrigerant circuit, efficiently meeting the battery temperature control and cab comfort requirements, the battery heat pump system and the cab heat pump system being isolated from the cab, effectively improving the safety of the heat management system; a three-way valve, a four-way valve and a nine-way valve combination effectively realizing the cooling liquid shunting and converging requirements, being applicable to 25 working modes of the heat pump; a front-end heat dissipation module comprising independent and parallel modes, capable of realizing the motor self-circulation heat dissipation and heating the cooling liquid by using the motor waste heat, being particularly applicable to the motor waste heat recovery and heating of the battery, and effectively reducing the energy consumption of the compressor and the electric heating PTC; the cab inlet parallel module can be selected, the cooling liquid entering the cab cold air core and the cab warm air core respectively, and the cab heat exchange amount is increased; the low-temperature cooling liquid flows into the cold air core, the cab electric heating PTC is started, and the system is applicable to the cab defogging mode.

Description

Technical Field

[0001] This invention belongs to the field of thermal management technology for electric commercial vehicles, and relates to a CO2 indirect heat pump system and an electric commercial vehicle. Background Technology

[0002] The application of electric commercial vehicles promotes the low-carbon, high-quality, and sustainable development of the freight industry. The widespread adoption of electric commercial vehicles reduces the transportation industry's dependence on fossil fuels, effectively lowering greenhouse gas emissions. To prevent battery thermal runaway, ensure optimal battery operating temperature, and improve cab comfort, an efficient thermal management system has become an indispensable part of electric commercial vehicles.

[0003] Electric commercial vehicles carry high-energy-density, high-output power batteries. Under harsh conditions such as high temperatures in summer and prolonged heavy-load uphill driving, the batteries generate significant heat. The thermal management system must effectively reduce battery temperature to prevent thermal runaway. In low-temperature winter conditions, PTC heating of the battery and cab consumes a large amount of electrical energy, significantly impacting driving range. The heat pump reverse cycle operating mode eliminates the excessive reliance on PTC heating during heating operations, providing an effective solution to improve driving range. Furthermore, compared to traditional air conditioning systems that integrate cooling, PTC heating, and motor liquid cooling, the heat pump system can comprehensively address the temperature control needs of the battery and cab, recover waste heat from the motor, and improve system energy efficiency.

[0004] The working fluid in a heat pump is a key factor in improving system performance and driving the development of thermal management systems. Environmentally friendly refrigerant CO2, due to its extremely low global warming potential and high heating efficiency, has become an ideal alternative to traditional refrigerants. However, the extremely high operating pressure and safety requirements of CO2 have been significant obstacles to its widespread application.

[0005] In summary, developing high-performance heat pump systems for electric commercial vehicles to efficiently meet the significantly different heating and cooling needs of the battery pack and the cab has become one of the major challenges at present. Furthermore, separating the high-pressure refrigerant circuit from the cab to improve system safety is also a key technical issue that needs to be addressed to promote the application of CO2 heat pump systems. Summary of the Invention

[0006] The purpose of this invention is to solve the problem of low heating efficiency in low-temperature operating conditions of thermal management systems for electric commercial vehicles in the prior art, and to provide a CO2 indirect heat pump system and an electric commercial vehicle.

[0007] To achieve the above objectives, the present invention employs the following technical solution:

[0008] The present invention proposes a CO2 indirect heat pump system, comprising a battery heat pump system, a cab heat pump system, a front-end heat dissipation module, and a cab module;

[0009] The battery heat pump system is used to control the battery temperature in electric commercial vehicles.

[0010] The cab heat pump system is used to control the temperature inside the electric commercial vehicle cab.

[0011] The front-end heat dissipation module is used to realize the heat pump system's circulating heat dissipation and heat absorption;

[0012] The cab module is used to regulate the heat exchanger of the cab.

[0013] Specifically, the first port of the battery heat pump system is connected to the first port of the cab heat pump system, the second port of the battery heat pump system is connected to the first port of the front-end heat dissipation module, the second port of the front-end heat dissipation module is connected to the second port of the cab heat pump system, and the third port of the cab heat pump system is connected to the cab module.

[0014] Preferably, the battery heat pump system includes a refrigerant circuit and a coolant circuit; the refrigerant circuit includes a first compressor, a first gas cooler, a first regenerator, a first throttle valve, a first evaporator, a first gas-liquid separator, and a first regenerator bypass valve; the coolant circuit includes a first water pump, a four-way valve, a battery heating PTC, a second water pump, a first proportional three-way valve, and a fifth proportional three-way valve.

[0015] The outlet of the first compressor is connected to the refrigerant inlet of the first gas cooler. The outlet of the first gas cooler is connected to the inlet of the first evaporator through the first pipe of the first regenerator. The outlet of the first evaporator is connected to the second pipe of the first regenerator through the first gas-liquid separator. The outlet of the second pipe is connected to the inlet of the first compressor. A bypass valve for the first regenerator is provided between the outlet of the first gas-liquid separator and the inlet of the first compressor.

[0016] The outlet of the first water pump is connected to port A of the four-way valve. Port D of the four-way valve is connected to the inlet of the power battery coolant via the battery heating PTC. The outlet of the power battery coolant is connected to port F of the nine-way valve. Port H of the nine-way valve is connected to the inlet of the first water pump. Port C of the first proportional three-way valve is connected to the inlet of the second water pump. The outlet of the second water pump is connected to port C of the four-way valve via the first evaporator. Port B of the four-way valve is connected to port A of the fifth proportional three-way valve. Port B of the fifth proportional three-way valve is connected to the front-end heat dissipation module. Port C of the fifth proportional three-way valve is connected to port E of the nine-way valve. Port B of the first proportional three-way valve is connected to port G of the nine-way valve. Port A of the first proportional three-way valve is connected to the cab heat pump system.

[0017] Preferably, it also includes an air conditioning unit, which includes a cold air core, a warm air core, and a fan;

[0018] The cold air core and the warm air core are connected in series, and the air blown out by the fan passes through the warm air core and the cold air core in sequence.

[0019] Preferably, the cab heat pump system includes a cab heat pump system refrigerant circuit and a cab heat pump system coolant circuit; the cab heat pump system refrigerant circuit includes a second compressor, a second gas cooler, a second regenerator, a second throttle valve, a second evaporator, a second gas-liquid separator, and a second regenerator bypass valve; the cab heat pump system coolant circuit includes a third water pump, a cab heating PTC, a fourth proportional three-way valve, a third proportional three-way valve, a fourth water pump, and a second proportional three-way valve;

[0020] The outlet of the second compressor is connected to the refrigerant inlet of the second gas cooler. The outlet of the second gas cooler is connected to the inlet of the second evaporator through the first pipe of the second regenerator. The outlet of the second evaporator is connected to the second pipe of the second regenerator through the second gas-liquid separator. The outlet of the second pipe is connected to the inlet of the second compressor. A bypass valve for the second regenerator is installed between the outlet of the second gas-liquid separator and the inlet of the second compressor.

[0021] The outlet of the third water pump is connected to port I of the nine-way valve, port C of the fourth proportional three-way valve is connected to port B of the third proportional three-way valve, port A of the third proportional three-way valve is connected to the inlet of the third water pump, port C of the third proportional three-way valve is connected to port B of the nine-way valve, port A of the fourth proportional three-way valve is connected to port B of the second proportional three-way valve, port A of the second proportional three-way valve is connected to the second evaporator through the fourth water pump, the outlet of the second evaporator is connected to port A of the nine-way valve, port C of the second proportional three-way valve is connected to the battery heat pump system, and port B of the fourth proportional three-way valve is connected to the cab module.

[0022] Preferably, when the cab module is an entrance parallel module, the entrance parallel module includes a cab heating PTC, an eighth proportional three-way valve, and a ninth proportional three-way valve;

[0023] The eighth proportional three-way valve A port is connected to the nine-way valve C port, the eighth proportional three-way valve B port is connected to the cold air core inlet, the eighth proportional three-way valve C port is connected to the cab heating PTC, the ninth proportional three-way valve B port is connected to the warm air core outlet, the ninth proportional three-way valve C port is connected to the cold air core outlet, and the ninth proportional three-way valve A port is connected to the cab heat pump system.

[0024] Preferably, when the cab module is an entrance series module, the entrance series module includes a cab heating PTC;

[0025] The C port of the nine-way valve is connected to the inlet of the cold air core, and the outlet of the cold air core is connected to the heating air core through the PTC in the cab. The heating air core is connected to the heat pump system in the cab.

[0026] Preferably, the front-end heat dissipation module includes a first radiator, a second radiator, a sixth proportional three-way valve, a seventh proportional three-way valve, a cooling fan, a fifth water pump, and a motor;

[0027] The C port of the sixth proportional three-way valve is connected to the first radiator. The B port of the sixth proportional three-way valve is connected to the C port of the seventh proportional three-way valve through the second radiator. The B port of the sixth proportional three-way valve is connected to the motor through the fifth water pump. The motor outlet is connected to the B port of the seventh proportional three-way valve. The outlet of the first radiator is connected to the A port of the seventh proportional three-way valve and then to the D port of the nine-way valve. A cooling fan is installed at the second radiator. The A port of the sixth proportional three-way valve is connected to the battery heat pump system.

[0028] Preferably, the front-end heat dissipation module is in independent mode:

[0029] The sixth proportional three-way valve connects ports A and C, and closes port B. The seventh proportional three-way valve connects ports B and C, and closes port A. The motor coolant is independently circulated and cooled by the fifth water pump, the motor, the seventh proportional three-way valve, and the second radiator. The coolant exchanges heat with the air through the first radiator.

[0030] Preferably, the front-end heat dissipation modules are connected in parallel:

[0031] The sixth proportional three-way valve has ports A, B, and C connected for proportional distribution. The seventh proportional three-way valve has ports A and B connected and port C closed. The coolant exchanges heat with the motor through port B of the sixth proportional three-way valve and the fifth water pump. At the same time, the coolant exchanges heat with the air through port C of the sixth proportional three-way valve and the first radiator.

[0032] An electric commercial vehicle that uses a CO2 indirect heat pump system.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] This invention provides a CO2 indirect heat pump system, comprising a battery heat pump system and a cab heat pump system with independent refrigerant circuits. This system efficiently meets the requirements for battery temperature control and cab comfort. Both the battery and cab heat pump systems are isolated from the cab, effectively improving the safety of the thermal management system. The front-end heat dissipation module proposed in this invention includes independent and parallel modes, enabling self-circulation heat dissipation of the motor and utilizing motor waste heat to heat the coolant. It is particularly suitable for recovering motor waste heat to heat the battery, effectively reducing the energy consumption of the compressor and electric heating PTC. The parallel module at the cab inlet of this invention allows coolant to enter the cab's cold air core and warm air core separately, increasing the cab's heat exchange capacity. Low-temperature coolant flows into the cold air core, activating the cab's electric heating PTC, suitable for the cab defogging mode. Therefore, the technical solution provided by this invention offers a heat pump system with high-efficiency heating performance. The refrigerant circuits of the battery heat pump system and the cab heat pump system operate independently, effectively alleviating the pressure on the thermal management system's cooling capacity demand caused by the high heat generation of the electric commercial vehicle battery. Furthermore, the high-pressure refrigerant circuit is isolated from the cab, improving system safety. The front-end heat dissipation module includes independent and parallel modes, which recovers waste heat from the motor to heat the battery, thereby improving system energy efficiency.

[0035] Furthermore, the combination of three-way, four-way, and nine-way valves effectively fulfills the requirements for coolant diversion and merging, and is suitable for 25 operating modes of the heat pump. Additionally, a battery-heated PTC is installed at the D outlet of the four-way valve for auxiliary heating under extreme low-temperature conditions. A cab-heated PTC is installed at the inlet of the heater core for auxiliary heating in the demisting mode of the cab heat pump system and under extreme low-temperature conditions.

[0036] Furthermore, when the motor temperature is low, the front-end heat dissipation module switches to parallel mode, and the coolant flowing through the motor reduces the temperature; when the motor temperature is high, the front-end heat dissipation module switches to independent mode, and the motor self-circulates to dissipate heat; when the motor temperature is high and the battery has a heating request, the waste heat of the motor is recovered to heat the battery, reducing the energy consumption of the battery heating PTC and the energy consumption of the first compressor. Attached Figure Description

[0037] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a diagram of the CO2 indirect heat pump system applicable to electric commercial vehicles according to the present invention.

[0039] Figure 2This is a schematic diagram of the cab and battery heat pump heating mode in the independent mode of the front-end heat dissipation module of the present invention.

[0040] Figure 3 This is a schematic diagram of the cab and battery heat pump heating mode in the parallel connection mode of the front-end heat dissipation module of the present invention.

[0041] Figure 4 This is a schematic diagram of the cab cooling and battery forced cooling modes of the present invention.

[0042] Figure 5 This is a schematic diagram of the battery self-circulating heat dissipation mode of the present invention.

[0043] Figure 6 This is a schematic diagram of the motor waste heat heating battery mode of the present invention.

[0044] Figure 7 This is a schematic diagram of the defogging mode in the driver's cab of the present invention.

[0045] Figure 8 This is a schematic diagram of the cab cooling mode implemented by the parallel module at the cab entrance of the present invention.

[0046] The components include: 1. First compressor; 2. First gas cooler; 3. First regenerator; 4. First throttle valve; 5. First evaporator; 6. First gas-liquid separator; 7. First regenerator bypass valve; 8. First water pump; 9. Second water pump; 10. First proportional three-way valve; 11. Nine-way valve; 12. Four-way valve; 13. Battery heating PTC; 14. Power battery; 15. Fifth proportional three-way valve; 16. Sixth proportional three-way valve; 17. First radiator; 18. Second radiator; 19. Seventh proportional three-way valve; 20. Cooling fan; 21. Fifth water pump; 22. Motor; 23. Driver. 24. Driver's cab heating PTC; 25. Cold air core; 26. Warm air core; 27. Fan; 28. Fourth proportional three-way valve; 29. ​​Third proportional three-way valve; 30. Second proportional three-way valve; 31. Fourth water pump; 32. Second evaporator; 33. Second gas-liquid separator; 34. Second throttle valve; 35. Second regenerator; 36. Second regenerator bypass valve; 37. Third water pump; 38. Second gas cooler; 39. Second compressor; 40. Second expansion tank; 41. First expansion tank; 42. Third expansion tank; 43. Eighth proportional three-way valve; 44. Ninth proportional three-way valve. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0048] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0049] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0050] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention 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 a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0051] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0052] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" 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 of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0053] The present invention will now be described in further detail with reference to the accompanying drawings:

[0054] The present invention proposes a CO2 indirect heat pump system, comprising a battery heat pump system, a cab heat pump system, a front-end heat dissipation module, and a cab module;

[0055] The battery heat pump system is used to control the battery temperature in electric commercial vehicles.

[0056] The cab heat pump system is used to control the temperature inside the electric commercial vehicle cab.

[0057] The front-end heat dissipation module is used to realize the circulating heat dissipation and heat absorption of the heat pump system.

[0058] The cab module is used to regulate the heat exchanger of the cab.

[0059] Specifically, the first port of the battery heat pump system is connected to the first port of the cab heat pump system, the second port of the battery heat pump system is connected to the first port of the front-end heat dissipation module, the second port of the front-end heat dissipation module is connected to the second port of the cab heat pump system, and the third port of the cab heat pump system is connected to the cab module.

[0060] The CO2 indirect heat pump integrated module includes a battery heat pump system and a cab heat pump system. The battery heat pump system includes a refrigerant circuit and a coolant circuit. The refrigerant circuit includes, in order of flow direction, a first compressor 1, a first gas cooler 2, a first regenerator 3, a first throttle valve 4, a first evaporator 5, a first gas-liquid separator 6, and a first regenerator bypass valve 7. The coolant circuit includes a first water pump 8, a four-way valve 12, a battery heating PTC 13, a second water pump 9, a first proportional three-way valve 10, and a fifth proportional three-way valve 15.

[0061] In the refrigerant circuit of the battery heat pump system, the outlet of the first compressor 1 is connected to the refrigerant inlet of the first gas cooler 2, the outlet of the first gas cooler 2 is connected to the inlet of the first evaporator 5 through the first pipe of the first regenerator 3, the outlet of the first evaporator 5 is connected to the second pipe of the first regenerator 3 through the first gas-liquid separator 6, and the outlet of the second pipe is connected to the inlet of the first compressor 1; a first regenerator bypass valve 7 is provided between the outlet of the first gas-liquid separator 6 and the inlet of the first compressor 1; a first throttling valve 4 is provided between the first regenerator 3 and the first evaporator 5;

[0062] In the coolant circuit of the battery heat pump system, the outlet of the first water pump 8 is connected to port A of the four-way valve 12 via the first gas cooler 2. Port D of the four-way valve 12 is connected to the coolant inlet of the power battery 14 via the battery heating PTC 13. The coolant outlet of the power battery 14 is connected to port F of the nine-way valve 11. Port H of the nine-way valve 11 is connected to the inlet of the first water pump 8. Port C of the first proportional three-way valve is connected to the inlet of the second water pump 9. The outlet of the second water pump 9 is connected to port C of the four-way valve 12 via the first evaporator 5. Port B of the four-way valve 12 is connected to port A of the fifth proportional three-way valve 15. Port B of the fifth proportional three-way valve 15 is connected to the front-end heat dissipation module. Port C of the fifth proportional three-way valve 15 is connected to port E of the nine-way valve 11. Port B of the first proportional three-way valve 10 is connected to port G of the nine-way valve 11. Port A of the first proportional three-way valve 10 is connected to the cab heat pump system.

[0063] The four-way valve 12 is equipped with a battery heating PTC 13 at the D outlet end. The four-way valve 12 has the following working modes: Mode 1: AB end and CD end are connected; Mode 2: AD end and BC end are connected.

[0064] The nine-way valve 11 has the following working modes: Mode 1: AC end, EI end, FG end and DH(B) end are connected, where the three ports of DHB form a proportional distribution structure; Mode 2: CI end, EA end, DG end and FH(B) end are connected, where FHB forms a proportional distribution structure; The first proportional three-way valve 10 and the second proportional three-way valve 29 are connected to distribute the coolant of the battery heat pump system and the coolant of the cab heat pump system; The third proportional three-way valve 28 and the fourth proportional three-way valve 27 are connected to switch the cooling mode and heating mode of the cab heat pump system.

[0065] The battery heat pump system has the following operating modes:

[0066] Forced cooling mode for the battery: The first compressor 2 starts, the first regenerator bypass valve 7 closes, and the refrigerant circuit circulation of the battery heat pump system is completed; the first water pump 8 and the second water pump 9 start, the first proportional three-way valve 10 is open at the BC end, the fifth proportional three-way valve 15 is open at the AB end, the sixth proportional three-way valve 16 is open at the AC end, the nine-way valve 11 switches to mode 1, and the four-way valve 12 switches to mode 1, and the coolant circuit circulation of the battery heat pump system is completed;

[0067] Battery self-circulation heat dissipation mode: First compressor 1 is turned off, and the refrigerant circuit circulation of the battery heat pump system is turned off; second water pump 9 is started, the first proportional three-way valve 10 is opened at the BC end, the nine-way valve 11 switches to mode 1, and the four-way valve 12 switches to mode 1 to complete the circulation of the coolant circuit of the battery heat pump system.

[0068] Battery PTC heating mode: First compressor 1 is off, and the refrigerant circuit circulation of the battery heat pump system is closed; second water pump 9 is started, battery heating PTC 13 is started, the first proportional three-way valve 10 is open at the BC end, the nine-way valve 11 switches to mode 1, and the four-way valve 12 switches to mode 1 to complete the coolant circuit circulation of the battery heat pump system.

[0069] Battery heat pump heating mode: First compressor 1 starts, first regenerator bypass valve 7 is opened, and refrigerant circuit circulation is completed; first water pump 8 and second water pump 9 start, first proportional three-way valve 10 is opened at the BC end, fifth proportional three-way valve 15 is opened at the AB end, sixth proportional three-way valve 16 is opened at the AC end, and nine-way valve 11 switches to mode 2 to complete the coolant circuit circulation of the battery heat pump system;

[0070] Waste heat from motor heating battery mode: First compressor 1 is off, and the refrigerant circuit circulation of the battery heat pump system is shut down; First water pump 8, Second water pump 9, and Fifth water pump 21 are started; First proportional three-way valve 10 is open at the BC end; Fifth proportional three-way valve 15 is open at the AB end; Sixth proportional three-way valve 16 is open at the AB end; Seventh proportional three-way valve 19 is open at the AB end; Four-way valve 12 switches to mode 2; Nine-way valve 11 switches to mode 1, completing the coolant circuit circulation of the battery heat pump system.

[0071] The cab heat pump system includes a refrigerant circuit and a coolant circuit. The refrigerant circuit, in order of flow direction, includes a second compressor 38, a second gas cooler 37, a second regenerator 34, a second throttle valve 33, a second evaporator 31, a second gas-liquid separator 32, and a second regenerator bypass valve 35. The coolant circuit includes a third water pump 36, a cab heating PTC 23, a fourth proportional three-way valve 27, a third proportional three-way valve 28, a fourth water pump 30, and a second proportional three-way valve 29.

[0072] The coolant circuit of the cab heat pump system can be selected with a parallel module at the cab inlet, including: an eighth proportional three-way valve 42, a ninth proportional three-way valve 43, and a cab heating PTC 23;

[0073] In the refrigerant circuit of the cab heat pump system, the outlet of the second compressor 38 is connected to the refrigerant inlet of the second gas cooler 37. The outlet of the second gas cooler 37 is connected to the inlet of the second evaporator 31 through the first pipe of the second regenerator 34. The outlet of the second evaporator 31 is connected to the second pipe of the second regenerator 34 through the second gas-liquid separator 32. The outlet of the second pipe is connected to the inlet of the second compressor 38. A second regenerator bypass valve 35 is provided between the outlet of the second gas-liquid separator 32 and the inlet of the second compressor 38. A second throttling valve 33 is provided between the second regenerator 34 and the second evaporator 31.

[0074] In the coolant circuit of the cab heat pump system, the outlet of the third water pump 36 is connected to the port I of the nine-way valve 11 through the second gas cooler 37, the port C of the fourth proportional three-way valve 27 is connected to the port B of the third proportional three-way valve 28, the port A of the third proportional three-way valve 28 is connected to the inlet of the third water pump 36, the port C of the third proportional three-way valve 28 is connected to the port B of the nine-way valve 11, the port A of the fourth proportional three-way valve 27 is connected to the port B of the second proportional three-way valve 29, the port A of the second proportional three-way valve 29 is connected to the second evaporator 31 through the fourth water pump 30, the outlet of the second evaporator 31 is connected to the port A of the nine-way valve 11, the port C of the second proportional three-way valve 29 is connected to the port A of the first proportional three-way valve 10 of the battery heat pump system, and the port B of the fourth proportional three-way valve 27 is connected to the cab module.

[0075] The cab module includes a parallel entrance module and a series entrance module;

[0076] When the cab module is an inlet parallel module, the inlet parallel module includes a cab heating PTC23, an eighth proportional three-way valve 42, and a ninth proportional three-way valve 43; the A port of the eighth proportional three-way valve 42 is connected to the C port of the ninth valve 11, the B port of the eighth proportional three-way valve 42 is connected to the inlet of the cold air core 24, the C port of the eighth proportional three-way valve 42 is connected to the cab heating PTC23, the B port of the ninth proportional three-way valve 43 is connected to the outlet of the warm air core 25, the C port of the ninth proportional three-way valve 43 is connected to the outlet of the cold air core 24, and the A port of the ninth proportional three-way valve 43 is connected to the B port of the fourth proportional three-way valve 27 of the cab heat pump system;

[0077] When the cab module is an inlet series module, the inlet series module includes a cab heating PTC23; the C port of the nine-way valve 11 is connected to the inlet of the cold air core 24, the outlet of the cold air core 24 is connected to the warm air core 25 through the cab PTC 23, and the warm air core 25 is connected to the B port of the fourth proportional three-way valve 27 of the cab heat pump system.

[0078] The cab heat pump system has the following operating modes:

[0079] Cab cooling mode: The second compressor 38 starts, the second regenerator bypass valve 35 closes, and the refrigerant circuit circulation of the cab heat pump system is completed; the third water pump 36 and the fourth water pump 30 start, the second proportional three-way valve 29 AB end is open, the third proportional three-way valve 28 AC end is open, the fourth proportional three-way valve 27 AB end is open, the fifth proportional three-way valve 15 BC end is open, the sixth proportional three-way valve 16 AC end is open, and the nine-way valve 11 switches to mode 1, completing the coolant circuit circulation of the heat pump system;

[0080] Cab heat pump heating mode: The second compressor 38 starts, the second regenerator bypass valve 35 is opened, and the refrigerant circuit circulation is completed; the third water pump 36 and the fourth water pump 30 start, the first proportional three-way valve 10 AB end is opened, the second proportional three-way valve 29 AC end is opened, the third proportional three-way valve 28 AB end is opened, the fourth proportional three-way valve 27 BC end is opened, the fifth proportional three-way valve 15 BC end is opened, the sixth proportional three-way valve 16 AC end is opened, and the nine-way valve 11 switches to mode 2 to complete the coolant circuit circulation of the cab heat pump system;

[0081] PTC heating mode in the cab: the second compressor 38 is off, and the refrigerant circuit circulation of the cab heat pump system is closed; the third water pump 36 is started, the cab heating PTC is started, the third proportional three-way valve 28 is open at the AB end, the fourth proportional three-way valve 27 is open at the BC end, and the nine-way valve 11 switches to mode 2 to complete the cab coolant circuit circulation.

[0082] Cab defrosting modes: Cab PTC heating mode, the fan changes direction to heat the windshield for defrosting; Cab heat pump heating mode, the fan changes direction to heat the windshield for defrosting.

[0083] Cab defogging mode: The second compressor 38 starts, the second regenerator bypass valve 35 closes, and the refrigerant circuit circulation of the cab heat pump system is completed; the third water pump 36 and the fourth water pump 30 start, the cab heating PTC starts, the second proportional three-way valve 29 AB end is open, the third proportional three-way valve 28 AC end is open, the fourth proportional three-way valve 27 AB end is open, the fifth proportional three-way valve 15 BC end is open, the sixth proportional three-way valve 16 AC end is open, and the nine-way valve 11 switches to mode 1 to complete the coolant circuit circulation of the cab heat pump system.

[0084] The front-end heat dissipation module includes a first radiator 17, a second radiator 18, a sixth proportional three-way valve 16, a seventh proportional three-way valve 19, a cooling fan 20, a fifth water pump 21, and a motor 22.

[0085] In the front-end heat dissipation module, port C of the sixth proportional three-way valve 16 is connected to the first radiator 17, port B of the sixth proportional three-way valve 16 is connected to port C of the seventh proportional three-way valve 19 through the second radiator 18, port B of the sixth proportional three-way valve 16 is connected to the motor 22 through the fifth water pump 21, the outlet of the motor 22 is connected to port B of the seventh proportional three-way valve 19, the outlet of the first radiator 17 is connected to port A of the seventh proportional three-way valve 19 and then to port D of the nine-way valve 11, a cooling fan 20 is provided at the second radiator 18, and port A of the sixth proportional three-way valve 16 is connected to port B of the fifth proportional three-way valve 15 of the battery heat pump system.

[0086] The front-end heat dissipation module has independent and parallel modes:

[0087] Independent mode of front-end heat dissipation module: The AC port of the sixth proportional three-way valve 16 is connected and the B port is closed; the BC port of the seventh proportional three-way valve 19 is connected and the A port is closed; the motor coolant is independently circulated and cooled by the fifth water pump 21, the motor 22, the seventh proportional three-way valve 19 and the second radiator 18; the coolant of the heat pump integrated module exchanges heat with the air by passing through the first radiator 17.

[0088] Parallel mode of front-end heat dissipation module: The A, B, C ports of the sixth proportional three-way valve 16 are all connected for proportional distribution, the A and B ports of the seventh proportional three-way valve 19 are connected, and the C port is closed. The coolant of the heat pump integrated module exchanges heat with the motor 22 through the B port of the sixth proportional three-way valve 16 and the fifth water pump 21. At the same time, the coolant of the heat pump integrated module exchanges heat with the air through the C port of the sixth proportional three-way valve 16 and the first radiator 17.

[0089] The air conditioning unit includes a cold air core 24, a warm air core 25, and a fan 26.

[0090] In the air conditioning unit, the cold air core 24 and the warm air core 25 are connected in series, and the air blown out by the fan 26 passes through the warm air core 25 and the cold air core 24 in sequence.

[0091] The system also includes a first expansion tank 40, a second expansion tank 39, and a third expansion tank 41; the water inlet of the first expansion tank 40 is connected to the inlet of the second water pump 9 via a pipe, and the vent of the first expansion tank 40 is connected to the outlet of the first evaporator 5; the water inlet of the second expansion tank 39 is connected to the inlet of the fourth water pump 30 via a pipe, and the vent of the second expansion tank 39 is connected to the outlet of the second evaporator 31; the water inlet of the third expansion tank 41 is connected to the inlet of the fifth water pump 21 via a pipe, and the vent of the third expansion tank 41 is connected to the second radiator 18.

[0092] Both the battery heat pump system and the cab heat pump system are isolated from the cab. The refrigerant circuits of the battery heat pump system and the cab heat pump system are completely independent and can operate independently. The cab module, combined with the parallel module at the cab inlet, allows the coolant to be split through the eighth proportional three-way valve 42, flowing through the cold air core 24, the cab heating PTC 23, and the warm air core 25 respectively. The coolant then merges through the ninth proportional three-way valve 43, improving the cab's heat exchange performance. The coolant circuits of the battery heat pump system and the cab heat pump system are split through the first proportional three-way valve 10, the fourth proportional three-way valve 27, and the nine-way valve 11, and merged through the fifth proportional three-way valve 15 and the nine-way valve 11. When the motor temperature is low, the front-end heat dissipation module switches to parallel mode, and the coolant flowing through the motor reduces the temperature. When the motor temperature is high, the front-end heat dissipation module switches to independent mode, and the motor self-circulates to dissipate heat. When the motor temperature is high and the battery has a heating request, the waste heat of the motor is recovered to heat the battery, reducing the energy consumption of the battery heating PTC and the energy consumption of the first compressor.

[0093] Based on the five operating modes of the cab heat pump system, the four operating modes of the battery heat pump system, and the two operating modes of the front-end heat dissipation module under different working conditions, the CO2 indirect heat pump system proposed in this invention for electric commercial vehicles has 25 operating modes, as shown in the table below:

[0094]

[0095] Please see Figure 2This invention discloses an independent mode for the front-end heat dissipation module of a CO2 indirect heat pump system suitable for electric commercial vehicles, operating in both the cab and battery heat pump heating modes. The first compressor 1 and the second compressor 38 are started, and the first regenerator bypass valve 7 and the second regenerator bypass valve 35 are activated, completing the refrigerant circuit circulation. High-temperature refrigerant passes through the first gas cooler 2 and the second gas cooler 37 to heat the coolant, while low-temperature refrigerant passes through the first evaporator 5 and the second evaporator 31 to lower the coolant temperature. The first water pump 8, the second water pump 9, the third water pump 36, and the fourth water pump 30 are started, and the four-way valve 12 switches to mode 2, as does the nine-way valve 11. Low-temperature coolant from the battery heat pump system flows through the BC terminals of the four-way valve 12 into the A terminal of the fifth proportional three-way valve 15, and low-temperature coolant from the cab heat pump system flows through the AE terminal of the nine-way valve 11 into the C terminal of the fifth proportional three-way valve 15. After merging, the coolant passes through the AC terminal of the sixth proportional three-way valve 16 and exchanges heat with the air through the first radiator 17, before passing through the nine-way valve 11. The coolant from the DG terminal flows into the first proportional three-way valve 10, which then diverts the coolant. The BA terminal of the first proportional three-way valve 10 flows into the fourth water pump 30 via the AC terminal of the second proportional three-way valve 29, completing the low-temperature coolant circulation for the cab heat pump system. The BC terminal of the first proportional three-way valve 10 flows into the second water pump 9, completing the low-temperature coolant circulation for the battery heat pump system. The high-temperature coolant from the battery heat pump system flows into the power battery 14 via the AD terminal of the four-way valve 12, where it exchanges heat with the battery before flowing into the first water pump 8 via the FH terminal of the nine-way valve 11. The high-temperature coolant from the cab heat pump system flows sequentially into the cold air core 24 and the warm air core 25 via the IC terminal of the nine-way valve 11, then flows into the third water pump 36 via the BC terminal of the fourth proportional three-way valve 27 and the AB terminal of the third proportional three-way valve 28, completing the high-temperature coolant circulation for the cab heat pump system. The motor circuit coolant circulates sequentially through the fifth water pump 21, the motor 22, the BC terminal of the seventh proportional three-way valve 19, and the second radiator 18, reducing the motor temperature.

[0096] Please see Figure 3In an embodiment of the present invention, a CO2 indirect heat pump system for electric commercial vehicles is used in a parallel mode for the front-end heat dissipation module of the cab and battery heat pump heating mode. The first compressor 1 and the second compressor 38 are started, and the first regenerator bypass valve 7 and the second regenerator bypass valve 35 are opened to complete the refrigerant circuit circulation. The high-temperature refrigerant heats the coolant through the first gas cooler 2 and the second gas cooler 37, while the low-temperature refrigerant lowers the coolant temperature through the first evaporator 5 and the second evaporator 31. The first water pump 8, the second water pump 9, the third water pump 36, and the fourth water pump 30 are started, and the four-way valve 12 and the nine-way valve 11 switch to mode 2. The low-temperature coolant from the battery heat pump system flows into the fifth proportional three-way valve 15 through the BC terminals of the four-way valve 12, and the low-temperature coolant from the cab heat pump system flows into the fifth proportional three-way valve 15 through the AE terminal of the nine-way valve 11. After merging, part of the coolant passes through the sixth proportional three-way valve 16 through the C terminal and exchanges heat with the air through the first radiator 17, while the remaining coolant passes through the sixth proportional three-way valve 16. The B-end absorbs waste heat from the motor via the fifth water pump 21, motor 22, and the AB end of the seventh proportional three-way valve 19. It then flows through the DG end of the nine-way valve 11 into the first proportional three-way valve 10 for diversion. The BA end of the first proportional three-way valve 10 flows through the AC end of the second proportional three-way valve 29 into the fourth water pump 30, completing the low-temperature coolant circulation of the cab heat pump system. The BC end of the first proportional three-way valve 10 flows into the second water pump 9, completing the low-temperature coolant circulation of the battery heat pump system. The high-temperature coolant of the battery heat pump system flows through the AD end of the four-way valve 12 into the power battery 14, where it exchanges heat with the battery before flowing through the FH end of the nine-way valve 11 into the first water pump 8. The high-temperature coolant of the cab heat pump system flows through the IC end of the nine-way valve 11 into the cold air core 24 and the warm air core 25, then through the BC end of the fourth proportional three-way valve 27 and the AB end of the third proportional three-way valve 28 into the third water pump 36, completing the high-temperature coolant circulation of the cab heat pump system.

[0097] Please see Figure 4This invention discloses a CO2 indirect heat pump system for electric commercial vehicles, including a cab cooling and battery forced cooling mode. The first compressor 1 and the second compressor 38 are started, while the first regenerator bypass valve 7 and the second regenerator bypass valve 35 are closed, completing the refrigerant loop circulation. High-temperature refrigerant passes through the first gas cooler 2 and the second gas cooler 37 to heat the coolant, while low-temperature refrigerant passes through the first evaporator 5 and the second evaporator 31 to lower the coolant temperature. The first water pump 8, the second water pump 9, the third water pump 36, and the fourth water pump 30 are started, and the four-way valve 12 and the nine-way valve 11 switch to mode 1. The low-temperature coolant from the battery heat pump system flows into the power battery 14 through the CD end of the four-way valve 12, lowering the battery temperature, and then passes through the GF end of the nine-way valve 11 and the first proportional three-way valve 10. The coolant flows into the second water pump 9 from the BC end, completing the low-temperature coolant circulation of the battery heat pump system. The low-temperature coolant of the cab heat pump system enters the cold air core 24 and the warm air core 25 sequentially through the AC end of the nine-way valve 11, lowering the cab temperature. It then flows into the fourth water pump 30 through the AB ends of the fourth proportional three-way valve 27 and the second proportional three-way valve 29, completing the low-temperature coolant circulation of the cab heat pump system. The high-temperature coolant of the battery heat pump system flows into the A end of the fifth proportional three-way valve 15 through the AB end of the four-way valve 12, and into the C end of the fifth proportional three-way valve 15 through the IE end of the nine-way valve 11. After merging, it exchanges heat with the first radiator 17 through the AC end of the sixth proportional three-way valve 16. Part of the coolant flows into the first water pump 8 through the DH end of the nine-way valve 11, completing the high-temperature coolant circulation of the battery heat pump system. Part of the coolant flows through the DB end of the nine-way valve 11 and the third proportional three-way valve 28. The AC end flows into the third water pump 36 to complete the circulation of high-temperature coolant in the cab heat pump system; the motor circuit coolant passes through the fifth water pump 21, the motor 22, the BC end of the seventh proportional three-way valve 19, and the second radiator 18 in sequence to complete the circulation and reduce the motor temperature.

[0098] Please see Figure 5 According to an embodiment of the present invention, a self-circulating cooling mode of a CO2 indirect heat pump system for electric commercial vehicles is provided. The second water pump 9 is started, and the four-way valve 12 switches to mode 1 and the nine-way valve 11 switches to mode 1. The coolant flows into the power battery 14 through the second water pump 9, the second evaporator 5, and the CD end of the four-way valve 12 to exchange heat and reduce the battery temperature. Then, it flows into the second water pump 9 through the FG end of the nine-way valve 11 and the BC end of the first proportional three-way valve 10, thus completing the self-circulation of the coolant in the battery heat pump system.

[0099] Please see Figure 6According to an embodiment of the present invention, a CO2 indirect heat pump system for electric commercial vehicles uses waste heat from the motor to heat the battery. The first water pump 8, the second water pump 9, and the fifth water pump 21 are started. Coolant flows into the power battery 14 through the first water pump 8 and the AD end of the four-way valve 12 for heat exchange. It then flows into the second water pump 9 through the GF end of the nine-way valve 11 and the BC end of the first proportional three-way valve 10. After passing through the BC end of the four-way valve 12, the AB end of the fifth proportional three-way valve 15, the AB end of the sixth proportional three-way valve 16, and the fifth water pump 21, it flows into the motor 22 to absorb waste heat from the motor 22. After heat exchange, it flows into the first water pump 8 through the AB end of the seventh proportional three-way valve 19 and the DH end of the nine-way valve 11, completing the coolant circulation of the battery heat pump system and heating the battery with waste heat from the motor.

[0100] Please see Figure 7 In a CO2 indirect heat pump system for electric commercial vehicles, in the defogging mode of the cab, the second compressor 38 starts, completing the refrigerant circuit circulation; the third water pump 36 and the fourth water pump 30 start, the cab heating PTC 23 starts, and the nine-way valve 11 switches to mode 1; the high-temperature coolant of the cab heat pump system flows into the third water pump 36 through the IE end of the nine-way valve 11, the BC end of the fifth proportional three-way valve 15, the AC end of the sixth proportional three-way valve 16, the first radiator 17, the BD end of the nine-way valve 11, and the AC end of the third proportional three-way valve 28 to exchange heat with the high-temperature refrigerant; the low-temperature coolant of the cab low-temperature heat pump system enters the cold air core 24 through the second evaporator 31 and the AC end of the nine-way valve 11, and the low-temperature coolant flowing out of the cold air core 24 enters the warm air core 25 through the cab heating PTC 23 to exchange heat with the cab, and then the high-temperature coolant passes through the AB end of the fourth proportional three-way valve 27 and the second proportional three-way valve 29. The water from ends A and B, and the fourth water pump 30, enters the second evaporator 31 to complete the low-temperature coolant circulation;

[0101] Please see Figure 8This invention discloses an indirect CO2 heat pump system for electric commercial vehicles. The system achieves cab cooling mode via a parallel module at the cab inlet. The second compressor 38 starts, and the second regenerator bypass valve 35 closes, completing the refrigerant loop circulation. High-temperature coolant exchanges heat with the first radiator 17 via the nine-way valve 11 (IE end), the fifth proportional three-way valve 15 (BC end), and the sixth proportional three-way valve 16 (AC end). It then flows into the third water pump 36 via the nine-way valve 11 (DB end) and the third proportional three-way valve 28 (AC end), completing the high-temperature coolant circulation in the cab heat pump system. Low-temperature coolant is split via the second evaporator 31, the nine-way valve 11 (AC end), and the eighth proportional three-way valve 42. Part of the coolant flows into the cold air core 24 via the AB end for heat exchange and then through the ninth proportional three-way valve 43 (AC end). Another part flows into the warm air core 25 via the eighth proportional three-way valve 42 (AC end) for heat exchange and then through the ninth proportional three-way valve 43 (AB end). The two portions of coolant merge via the ninth proportional three-way valve 43 and then flow through the fourth proportional three-way valve 27. The AB end, the second proportional three-way valve 29, and the fourth water pump 30 return to the inlet of the second evaporator 31 to complete the low-temperature coolant circulation of the cab heat pump module.

[0102] In summary, this invention discloses a CO2 indirect heat pump system suitable for electric commercial vehicles, comprising: a battery heat pump system and a cab heat pump system with independent refrigerant circuits, a front-end heat dissipation module operating in parallel and independent modes, a multi-way valve assembly, and a cab module. The proposed system can achieve 25 operating modes, including motor waste heat utilization, cab heating, defrosting, defogging, forced battery cooling, heating, and self-circulating heat dissipation. It solves problems such as flow distribution in integrated cooling systems, excessive dependence on electric heating, and poor heating performance of R134a heat pumps under low-temperature conditions, providing an efficient, reliable, and safe thermal management solution for electric vehicles equipped with high-energy-density, high-output-power batteries. The heat pump system includes a battery heat pump system with an independent refrigerant circuit and a cab heat pump system, efficiently meeting the needs of battery temperature control and cab comfort control. The CO2 indirect heat pump integrated module is isolated from the cab, effectively improving the safety of the thermal management system. The independent mode of the front-end heat dissipation module enables self-circulation heat dissipation of the motor, while the parallel mode enables the motor's waste heat to heat the battery, effectively reducing the energy consumption of the compressor and electric heating PTC. Through the parallel module at the cab inlet, coolant enters the cab's cold air core and warm air core separately, increasing the cab's heat exchange capacity. Low-temperature coolant flows into the warm air core 25, and the cab electric heating PTC 23 is activated, suitable for the cab defogging mode. This invention addresses the challenges of integrated cooling system flow distribution, excessive dependence on electric heating, and poor low-temperature heating performance of R134a heat pumps in electric commercial vehicles equipped with high-energy-density, high-output-power batteries. It promotes the application and popularization of CO2 heat pump systems, facilitates the low-carbon and sustainable development of the freight industry, and makes a significant contribution to environmental protection, alleviating the fossil fuel crisis, and achieving carbon neutrality and carbon peaking.

[0103] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A CO2 indirect heat pump system, characterized in that, This includes a battery heat pump system, a cab heat pump system, a front-end heat dissipation module, and a cab module; The battery heat pump system is used to control the battery temperature in electric commercial vehicles. The cab heat pump system is used to control the temperature inside the electric commercial vehicle cab. The front-end heat dissipation module is used to realize the heat pump system's circulating heat dissipation and heat absorption; The cab module is used to regulate the heat exchanger of the cab. Among them, the first port of the battery heat pump system is connected to the first port of the cab heat pump system, the second port of the battery heat pump system is connected to the first port of the front heat dissipation module, the second port of the front heat dissipation module is connected to the second port of the cab heat pump system, and the third port of the cab heat pump system is connected to the cab module. The outlet of the first compressor (1) in the battery heat pump system is connected to the refrigerant inlet of the first gas cooler (2). The outlet of the first gas cooler (2) is connected to the inlet of the first evaporator (5) through the first pipe of the first regenerator (3). The outlet of the first evaporator (5) is connected to the second pipe of the first regenerator (3) through the first gas-liquid separator (6). The outlet of the second pipe is connected to the inlet of the first compressor (1). A first regenerator bypass valve (7) is set between the outlet of the first gas-liquid separator (6) and the inlet of the first compressor (1). The outlet of the first water pump (8) is connected to the A port of the four-way valve (12). The D port of the four-way valve (12) is connected to the coolant inlet of the power battery (14) through the battery heating PTC (13). The coolant outlet of the power battery (14) is connected to the F port of the nine-way valve (11). The H port of the nine-way valve (11) is connected to the inlet of the first water pump (8). A first proportional three-way valve (10) is also connected. Port C is connected to the inlet of the second water pump (9), and the outlet of the second water pump (9) is connected to the four-way valve (12) at port C through the first evaporator (5). Port B of the four-way valve (12) is connected to the fifth proportional three-way valve (15) at port A. Port B of the fifth proportional three-way valve (15) is connected to the front-end heat dissipation module. Port C of the fifth proportional three-way valve (15) is connected to the nine-way valve (11) at port E. Port B of the first proportional three-way valve (10) is connected to the nine-way valve (11) at port G. Port A of the first proportional three-way valve (10) is connected to the cab heat pump system. The cold air core (24) and the warm air core (25) in the air conditioning unit are connected in series, and the air blown out by the fan (26) passes through the warm air core (25) and the cold air core (24) in sequence. The outlet of the second compressor (38) in the cab heat pump system is connected to the refrigerant inlet of the second gas cooler (37). The outlet of the second gas cooler (37) is connected to the inlet of the second evaporator (31) through the first pipe of the second regenerator (34). The outlet of the second evaporator (31) is connected to the second pipe of the second regenerator (34) through the second gas-liquid separator (32). The outlet of the second pipe is connected to the inlet of the second compressor (38). A bypass valve (35) for the second regenerator is installed between the outlet of the second gas-liquid separator (32) and the inlet of the second compressor (38). The outlet of the third water pump (36) is connected to port I of the nine-way valve (11). The port C of the fourth proportional three-way valve (27) is connected to port B of the third proportional three-way valve (28). The port A of the third proportional three-way valve (28) is connected to the inlet of the third water pump (36). The port C of the third proportional three-way valve (28) is connected to port B of the nine-way valve (11). The port A of the fourth proportional three-way valve (27) is connected to the second proportional three-way valve (29). Port B, the second proportional three-way valve (29) is connected to the second evaporator (31) via the fourth water pump (30), and the outlet of the second evaporator (31) is connected to the nine-way valve (11). Port A, the second proportional three-way valve (29) is connected to the battery heat pump system via Port C, and the fourth proportional three-way valve (27) is connected to the cab module via Port B. When the cab module is an inlet parallel module, the inlet parallel module includes a cab heating PTC (23), an eighth proportional three-way valve (42), and a ninth proportional three-way valve (43); the A port of the eighth proportional three-way valve (42) is connected to the C port of the nine-way valve (11), the B port of the eighth proportional three-way valve (42) is connected to the inlet of the cold air core (24), the C port of the eighth proportional three-way valve (42) is connected to the cab heating PTC (23), the B port of the ninth proportional three-way valve (43) is connected to the outlet of the warm air core (25), the C port of the ninth proportional three-way valve (43) is connected to the outlet of the cold air core (24), and the A port of the ninth proportional three-way valve (43) is connected to the cab heat pump system; when the cab module is an inlet series module, the inlet series module includes a cab heating PTC (23); the C port of the nine-way valve (11) is connected to the inlet of the cold air core (24), and the outlet of the cold air core (24) is connected to the cab PTC (23). Connect the heating core (25), and the heating core (25) is connected to the cab heat pump system; The sixth proportional three-way valve (16) in the front-end heat dissipation module is connected to the first radiator (17) via port C. The sixth proportional three-way valve (16) is connected to the seventh proportional three-way valve (19) via port B through the second radiator (18). The sixth proportional three-way valve (16) is connected to the motor (22) via the fifth water pump (21). The outlet of the motor (22) is connected to the seventh proportional three-way valve (19) via port B. The outlet of the first radiator (17) is connected to the seventh proportional three-way valve (19) via port A and then to the nine-way valve (11) via port D. A cooling fan (20) is provided at the second radiator (18). The sixth proportional three-way valve (16) is connected to the battery heat pump system via port A.

2. The CO2 indirect heat pump system according to claim 1, characterized in that, In independent mode, the front-end heat dissipation module is: The sixth proportional three-way valve (16) connects ports A and C, and closes port B. The seventh proportional three-way valve (19) connects ports B and C, and closes port A. The motor coolant is independently circulated and cooled by the fifth water pump (21), the motor (22), the seventh proportional three-way valve (19), and the second radiator (18). The coolant exchanges heat with the air by passing through the first radiator (17).

3. The CO2 indirect heat pump system according to claim 1, characterized in that, Front-end heat dissipation modules in parallel mode: The sixth proportional three-way valve (16) is connected to ports A, B and C for proportional distribution. The seventh proportional three-way valve (19) is connected to ports A and B and closed to port C. The coolant exchanges heat with the motor (22) through port B of the sixth proportional three-way valve (16) and the fifth water pump (21). At the same time, the coolant exchanges heat with the air through port C of the sixth proportional three-way valve (16) and the first radiator (17).

4. An electric commercial vehicle, characterized in that, The CO2 indirect heat pump system described in any one of claims 1 to 3 is adopted.

Images