A carbon dioxide heat pump air conditioner heat exchanger for vehicle thermal management, system and control method

Abstract

The application provides a carbon dioxide heat pump air conditioner heat exchanger for vehicle thermal management, a system and a control method, which balance refrigeration and heating. The heat exchange is achieved by arranging n on-off adjustment structures in a first main collecting pipe and a second main collecting pipe respectively. By controlling the on-off states of the 2n on-off adjustment structures, 2n+1 regions of the heat exchange channel can be in a series flow state or a parallel flow state, so that the flow distance of the refrigerant in the heat exchanger can be changed. Furthermore, the flow distance of the refrigerant in the heat exchanger can be changed according to the refrigeration and heating working conditions. The requirements of the heat exchanger structure for achieving better performance under the refrigeration and heating working conditions can be simultaneously considered. The refrigeration performance of the heat exchanger under the refrigeration working condition is improved, and the heating performance under the heating working condition is improved.

Description

Technical Field

[0001] This invention belongs to the technical field of transcritical carbon dioxide systems, and specifically relates to a carbon dioxide heat pump air conditioner heat exchanger, system and control method for vehicle thermal management that combines cooling and heating. Background Technology

[0002] The application and popularization of new energy electric vehicles have alleviated the problems of environmental pollution and fossil energy shortage. Due to the lack of recyclable engine waste heat, independent heat pump air conditioning systems have become an indispensable part of new energy electric vehicles.

[0003] Currently, CO2 has become one of the most ideal refrigerant choices for the next generation of electric vehicles due to its excellent properties. Compared with PTC auxiliary electric heating when using traditional refrigerants, CO2 heat pumps have superior heating performance, saving a significant amount of battery power in winter and indirectly extending the driving range of electric vehicles. As the core heat exchange equipment in the CO2 thermal management system, the performance of the heat exchanger has a significant impact on the overall performance and economy of the circulation system.

[0004] Currently, in refrigeration mode, the elongated channels in the heat exchanger structure cause a pressure drop in the refrigerant, leading to a decrease in the heat exchanger's refrigeration performance and a reduction in system refrigeration efficiency. However, in heating mode, the pressure drop has little impact on the heat exchanger's heating performance, and it is desirable for the refrigerant to circulate within longer channels to increase heat exchange. Therefore, to achieve better performance in refrigeration and heating modes, the requirements for heat exchanger structure and control differ, and how to simultaneously achieve both refrigeration and heating performance is a challenging problem. Thus, designing more advanced and higher-performance heat exchangers, along with corresponding system control methods, is particularly important for improving the system's refrigeration and heating performance. This is of significant value for accelerating the widespread application of transcritical CO2 systems and the development of green refrigerants. Summary of the Invention

[0005] The purpose of this invention is to provide a carbon dioxide heat pump air conditioner heat exchanger, system, and control method for vehicle thermal management that combines cooling and heating functions. This addresses the issue that in transcritical CO2 systems, the requirements for heat exchanger structure and control differ under cooling and heating conditions to achieve superior performance. The technical solution provided by this invention can improve the cooling performance of the heat exchanger under cooling conditions and simultaneously enhance its heating performance under heating conditions.

[0006] This invention is achieved through the following technical solution:

[0007] A carbon dioxide heat pump air conditioner heat exchanger for vehicle thermal management that combines cooling and heating includes: a first port, a second port, a first main manifold, a second main manifold, and a heat exchange channel.

[0008] The first port is connected to the first main manifold, the second port is connected to the second main manifold, the first main manifold is connected to one end of the heat exchange channel, and the second main manifold is connected to the other end of the heat exchange channel.

[0009] The first and second main manifolds are each equipped with n on / off adjustment structures, where n is a positive integer; the heat exchange channel is divided into 2n+1 regions, and by controlling the on / off state of the 2n on / off adjustment structures, the 2n+1 regions can be in a series flow state or a parallel flow state.

[0010] Preferably, it also includes baffles, wherein 2n baffles are provided, the baffles extend from one end of the heat exchange channel to the other end, the 2n baffles are arranged in parallel and divide the heat exchange channel into 2n+1 regions; the on / off adjustment structure is arranged in a one-to-one correspondence with the baffles, and the two on / off adjustment structures corresponding to two adjacent baffles are located in the first main manifold and the second main manifold, respectively.

[0011] Preferably, the on / off adjustment structure is a one-way flow device, or the on / off adjustment structure is a regulating valve.

[0012] A carbon dioxide heat pump air conditioning system for vehicle thermal management that combines cooling and heating includes an indoor heat exchanger, wherein the indoor heat exchanger is the aforementioned heat exchanger.

[0013] The control method for a vehicle thermal management carbon dioxide heat pump air conditioning system that combines cooling and heating, wherein the on / off adjustment structure is a one-way flow device, and the control method is as follows:

[0014] In cooling mode, the refrigerant enters the heat exchanger from the first port and flows out of the heat exchanger from the second port. The unidirectional flow device is in a flow state, and the 2n+1 regions of the heat exchange channel are in a parallel flow state.

[0015] In heating mode, the refrigerant enters the heat exchanger from the second port and flows out of the heat exchanger from the first port. The unidirectional flow devices are all in the reverse cut-off state, and the 2n+1 regions of the heat exchange channel are in series flow state.

[0016] The control method for a vehicle thermal management carbon dioxide heat pump air conditioning system that combines cooling and heating, wherein the on / off adjustment structure is a regulating valve, and the control method is as follows:

[0017] In cooling mode, the refrigerant enters the heat exchanger from the first port and flows out of the heat exchanger from the second port. All control valves are open, and the 2n+1 regions of the heat exchange channel are in parallel flow state. Alternatively, all control valves are closed, and the 2n+1 regions of the heat exchange channel are in series flow state.

[0018] In heating mode, the refrigerant enters the heat exchanger from the second port and flows out of the heat exchanger from the first port. All control valves are open, and the 2n+1 regions of the heat exchange channel are in parallel flow state. Alternatively, all control valves are closed, and the 2n+1 regions of the heat exchange channel are in series flow state.

[0019] Preferably, the system includes a compressor, and the system operates in two modes: an economy mode and a maximum capacity mode.

[0020] In cooling mode, the flow state of the 2n+1 zones of the heat exchange channel is controlled according to the following principles:

[0021] When the ambient temperature T < 30℃ and the compressor speed N < 6000r / min, all control and regulating valves are open, so that the 2n+1 regions of the heat exchange channel are in parallel flow state;

[0022] When the ambient temperature T < 30℃, the compressor speed N ≥ 6000 r / min, and the system is operating in economic mode, all control valves are open, so that the 2n+1 regions of the heat exchange channel are in parallel flow; when the system is operating in maximum capacity mode, all control valves are closed, so that the 2n+1 regions of the heat exchange channel are in series flow.

[0023] When the ambient temperature T≥30℃, the compressor speed N<6000r / min, and the system is operating in economic mode, all control valves are open, so that the 2n+1 regions of the heat exchange channel are in parallel flow; when the system is operating in maximum capacity mode, all control valves are closed, so that the 2n+1 regions of the heat exchange channel are in series flow.

[0024] When the ambient temperature T ≥ 30℃ and the compressor speed N ≥ 6000 r / min, if the supply air temperature T air When the temperature is ≥8℃ and the system is operating in economic mode, all control valves are open, so that the 2n+1 regions of the heat exchange channel are in parallel flow; when the system is operating in maximum capacity mode, all control valves are closed, so that the 2n+1 regions of the heat exchange channel are in series flow.

[0025] When the ambient temperature T ≥ 30℃ and the compressor speed N ≥ 6000 r / min, if the supply air temperature T air When the temperature is below 8℃ and the system is operating in maximum capacity mode, all control and regulating valves are closed, so that the 2n+1 regions of the heat exchange channel are in series flow.

[0026] Preferably, in heating mode, all control and regulating valves are closed, so that the 2n+1 regions of the heat exchange channel are in a series flow state.

[0027] Preferably, the system includes a compressor. In heating mode, the air temperatures T1 and T2 of the first and second (n+1)th regions of the heat exchange channel in series flow state are collected. When the temperature difference between T1 and T2 exceeds a preset value of m, if the compressor speed is less than 6000 r / min, the regulating valve is controlled to rotate by k°.

[0028] Preferably, in defrost and defogging mode, when the temperature difference between the evaporation temperature and the dew point temperature is greater than 5°C, all control valves are opened, so that the 2n+1 areas of the heat exchange channel are in parallel flow; when the temperature difference between the evaporation temperature and the dew point temperature is less than 5°C, all control valves are closed, so that the 2n+1 areas of the heat exchange channel are in series flow.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The heat exchanger of the present invention has n on / off adjustment structures respectively set in the first main manifold and the second main manifold. By controlling the on / off state of the 2n on / off adjustment structures, the 2n+1 regions of the heat exchange channel can be in a series flow state or a parallel flow state, thereby changing the distance of refrigerant flow in the heat exchanger. In addition, the distance of refrigerant flow in the heat exchanger can be changed according to the cooling and heating conditions. It can simultaneously take into account the requirements of the heat exchanger structure for better performance under cooling and heating conditions, improve the cooling performance of the heat exchanger under cooling conditions, and improve the heating performance under heating conditions.

[0031] Furthermore, the on / off adjustment structure is a unidirectional flow device, which can realize the flow function from the large end to the small end and the cut-off function from the small end to the large end. In cooling mode, 2n+1 zones of the heat exchange channel can be operated in parallel, and in heating mode, 2n+1 zones of the heat exchange channel can be operated in series.

[0032] Furthermore, the on / off regulating structure is a regulating valve, which can achieve bidirectional flow. Therefore, in cooling mode, the parallel and series switching of heat exchangers can be realized, and in heating mode, the parallel and series switching of heat exchangers can also be realized.

[0033] Based on the aforementioned heat exchanger, this invention proposes a heat pump air conditioning system and control method that combines cooling and heating. Through an on / off adjustment structure, the heat exchanger can be controlled in series and parallel under forward and reverse flow conditions, thereby improving performance and economic efficiency under different heat exchange modes.

[0034] Furthermore, in heating mode, the air temperatures T1 and T2 of the first and (2n+1)th regions divided by the heat exchange channel in the series flow state are collected by sensors. When the temperature difference between T1 and T2 exceeds a preset value m, if the compressor speed is less than 6000 r / min, the regulating valve is rotated by k°, i.e., the regulating valve is opened to a certain degree to alleviate the unevenness of the outlet air temperature and increase the comfort of personnel. If the compressor speed exceeds 6000 r / min, no action is taken to prevent the system from increasing uniformity but failing to achieve the heating target. This comprehensively considers both heat exchange capacity and outlet air uniformity. If the speed exceeds 6000 r / min, fine-tuning the regulating valve will lead to insufficient heat exchange capacity and fail to meet the demand. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art are briefly introduced below; obviously, the drawings described below are some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0036] Figure 1 This is a circulation diagram of a carbon dioxide heat pump air conditioning system for vehicle thermal management that combines cooling and heating, according to the present invention.

[0037] In the diagram: 1. Compressor; 2. Outdoor heat exchanger; 3. Intermediate heat exchanger; 4. Two-way throttle valve; 5. Indoor heat exchanger; 6. Gas-liquid separator; 7. First three-way valve; 8. Second three-way valve.

[0038] Figure 2 This is a design drawing of a carbon dioxide heat pump air conditioner heat exchanger for vehicle thermal management that combines cooling and heating, according to one embodiment of the present invention.

[0039] In the diagram: 9. First port; 10. Second port; 11. First main manifold; 12. Second main manifold; 13. First unidirectional flow device; 14. Second unidirectional flow device; 15. First partition; 16. Second partition.

[0040] Figure 3 This is a design drawing of a carbon dioxide heat pump air conditioner heat exchanger for vehicle thermal management that combines cooling and heating, according to another embodiment of the present invention.

[0041] In the diagram: 9. First port; 10. Second port; 11. First main manifold; 12. Second main manifold; 15. First baffle; 16. Second baffle; 17. First regulating valve; 18. Second regulating valve; 19. First regulating valve baffle pad; 20. First regulating valve baffle pad; 21. Second regulating valve baffle pad; 22. Second regulating valve baffle pad. Detailed Implementation

[0042] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0043] It should be noted that the terms "first," "second," etc., used in this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0044] The present invention will now be described in further detail with reference to the accompanying drawings:

[0045] Please see Figure 1 As shown in the figure, a carbon dioxide heat pump air conditioning system for vehicle thermal management that combines cooling and heating according to an embodiment of the present invention includes: a compressor 1, an outdoor heat exchanger 2, an intermediate heat exchanger 3, a two-way throttling valve 4, an indoor heat exchanger 5, a gas-liquid separator 6, a first three-way valve 7, and a second three-way valve 8.

[0046] The system:

[0047] The first three-way valve 7 has port a connected to the outlet of compressor 1, port b connected to the second port 10 of indoor heat exchanger 5, and port c connected to the first port of outdoor heat exchanger 2. The second three-way valve 8 has port a connected to the inlet of gas-liquid separator 6, port b connected to the second port 10 of indoor heat exchanger 5, and port c connected to the first port of outdoor heat exchanger 2. The second port of outdoor heat exchanger 2 is connected to the first port on the hot side of intermediate heat exchanger 3, and the second port on the hot side of intermediate heat exchanger 3 is connected to the first port 9 of indoor heat exchanger 5 via a bidirectional throttling valve 4. The outlet of gas-liquid separator 6 is connected to the cold side inlet of intermediate heat exchanger 3, and the cold side outlet of intermediate heat exchanger 3 is connected to the inlet of compressor 1.

[0048] When the circulating working fluid (i.e., refrigerant) flows in from the first port 9 and out from the second port 10, the indoor heat exchanger 5 is a three-pass heat exchanger; when the circulating working fluid flows in from the second port 10 and out from the first port 9, it is a single-pass heat exchanger.

[0049] Please see Figure 2 As shown, an indoor heat exchanger structure design for a CO2 heat pump air conditioner that combines cooling and heating according to an embodiment of the present invention includes: a first port 9, a second port 10, a first main manifold 11, a second main manifold 12, a first one-way flow device 13, a second one-way flow device 14, a first partition 15, a second partition 16, and a heat exchange channel.

[0050] The first port 9 is connected to the first main manifold 11, and the second port 10 is connected to the second main manifold 12. The first main manifold 11 is connected to one end of the heat exchange channel, and the second main manifold 12 is connected to the other end of the heat exchange channel. A first unidirectional flow device 13 is disposed in the first main manifold 11, and a second unidirectional flow device 14 is disposed in the second main manifold 12. The first partition 15 and the second partition 16 are located in the vertical direction of the second unidirectional flow device 14 and the first unidirectional flow device 13, respectively. That is, the line formed by the first partition 15 and the second unidirectional flow device 14, the second partition 16 and the first unidirectional flow device 13 is perpendicular to the direction of the first manifold 11 and the second manifold 12. The first partition 15 and the second partition 16 divide the heat exchange channel into a first region 201, a second region 202 and a third region 203.

[0051] The first one-way flow device 13 can realize the flow function from the large end to the small end and the cut-off function from the small end to the large end. The second one-way flow device 14 has the same function as the first one-way flow device 13. Both the first one-way flow device 13 and the second one-way flow device 14 are in a flow state when the refrigerant enters from the first port 9 of the indoor heat exchanger; and in a cut-off state when the refrigerant flows in from the second port 10 of the indoor heat exchanger. That is, when the refrigerant enters from the first port 9 of the indoor heat exchanger, the first region 201, the second region 202, and the third region 203 are in a parallel flow state; when the refrigerant flows in from the second port 10 of the indoor heat exchanger, the first region 201, the second region 202, and the third region 203 are in a series flow state.

[0052] The heights of the first baffle 15 and the second baffle 16 are respectively half the hydraulic diameter of the first main manifold 11 and the second main manifold 12.

[0053] The operation of an indoor heat exchanger using a one-way flow device in cooling and heating modes is as follows:

[0054] In cooling mode, the refrigerant is guaranteed to enter from the first port 9 and exit from the second port 10. The first one-way flow device 13 and the second one-way flow device 14 are both in the flow state. At this time, the first region 201, the second region 202, and the third region 203 are in parallel flow state, and the indoor heat exchanger is a single-pass heat exchanger, so as to minimize the flow loss of the circulating refrigerant and thus improve the cooling performance.

[0055] In heating mode, the refrigerant enters through the second port 10 and exits through the first port 9. At this time, both the first one-way flow device 13 and the second one-way flow device 14 are in a reverse-cut-off state. The refrigerant first enters the first region 201 and then sequentially enters the second region 202 and the third region 203. That is, the first region 201, the second region 202, and the third region 203 are in a series flow state, and the indoor heat exchanger is a three-pass heat exchanger. This ensures sufficient heat exchange capacity in heating mode.

[0056] The first one-way flow device 13 and the second one-way flow device 14 can be replaced by a first regulating valve 17 and a second regulating valve 18. In this case, the valve operation can be changed by system control rather than by the refrigerant flow direction. Please refer to [link to relevant documentation]. Figure 3 As shown, another embodiment of the present invention provides a heat exchanger structure design for a CO2 heat pump air conditioner that combines cooling and heating, comprising: a first port 9, a second port 10, a first main manifold 11, a second main manifold 12, a first regulating valve 17, a second regulating valve 18, a first partition 15, a second partition 16, a first regulating valve first baffle gasket 19, a first regulating valve second baffle gasket 20, a second regulating valve first baffle gasket 21, and a second regulating valve second baffle gasket 22.

[0057] The first regulating valve, baffle gasket 19 and baffle gasket 20, are used in conjunction with the first regulating valve 17, while the second regulating valve, baffle gasket 21 and baffle gasket 22, are used in conjunction with the second regulating valve 18. The first regulating valve 17 is a rotatable baffle structure. When it rotates to contact and tighten with the first regulating valve, baffle gasket 19, the first main manifold 11 is open; when it rotates to contact and tighten with the first regulating valve, baffle gasket 20, the first main manifold 11 is closed, thereby changing the refrigerant flow direction. The second regulating valve 18 has the same structure as the first regulating valve 17.

[0058] Using a unidirectional flow device only allows parallel operation in cooling mode and series operation in heating mode; while using an actuating valve allows switching between parallel and series operation of the heat exchangers in both cooling and heating modes. At this time, the first partition 15 and the second partition 16 divide the indoor heat exchanger 5 into a first region 201, a second region 202, and a third region 203.

[0059] When the working fluid enters from the first port 9 and flows out from the second port 10, the heat exchanger has two selectable flow modes:

[0060] Parallel flow state: After the refrigerant flows from the first port 9 through the first main manifold 11, it ensures that the first regulating valve 17 is locked in contact with the first regulating valve baffle gasket 19, and the second regulating valve 18 is locked in contact with the second regulating valve baffle gasket 21. At this time, the refrigerant simultaneously flows through the first region 301, the second region 302, and the third region 303, and then simultaneously enters the second main manifold 12, and then flows out from the second port 10. At this time, the indoor heat exchanger is a single-pass heat exchanger, and the heat exchangers operate in parallel.

[0061] In series flow mode: After the refrigerant flows from the first port 9 through the first main manifold 11, it ensures that the first regulating valve 17 is in contact with and locked by the first regulating valve second baffle gasket 20, and the second regulating valve 18 is in contact with and locked by the second regulating valve second baffle gasket 22. At this time, the refrigerant first enters the first region 301, then sequentially enters the second region 302 and the third region 303, and then enters the second main manifold 12, before flowing out from the second port 10. In this case, the indoor heat exchanger is a three-pass heat exchanger, and the heat exchangers operate in series.

[0062] When the working fluid enters through the second port 10 and exits through the first port 9, the heat exchanger has two selectable flow modes:

[0063] Parallel flow state: After the refrigerant flows from the second port 10 through the second main manifold 12, it ensures that the first regulating valve 17 is in contact with and locked by the first regulating valve baffle gasket 19, and the second regulating valve 18 is in contact with and locked by the second regulating valve baffle gasket 21. At this time, the refrigerant simultaneously flows through the first region 201, the second region 202, and the third region 203, and then simultaneously enters the first main manifold 11, and then flows out from the first port 9. At this time, the heat exchanger is a single-pass heat exchanger, and the heat exchangers are operating in parallel.

[0064] In series flow mode: After the refrigerant flows from the second port 10 through the second main manifold 12, it ensures that the first regulating valve 17 is in contact with and locked by the first regulating valve second baffle gasket 20, and the second regulating valve 18 is in contact with and locked by the second regulating valve second baffle gasket 22. At this time, the refrigerant first enters the third region 203, then sequentially enters the second region 202 and the first region 201, and then enters the first main manifold 11, before flowing out from the first port 9. In this case, the heat exchanger is a three-pass heat exchanger, and the heat exchangers operate in series.

[0065] In cooling mode, the flow status of the heat exchanger is determined based on the compressor speed, ambient temperature, air supply temperature, and system operating mode. The system operating modes are divided into economic mode and maximum capacity mode, which can be selected by the user.

[0066] When the ambient temperature T < 30℃ and the compressor speed N < 6000r / min, the performance and economic benefits of the system are almost the same regardless of whether it is operating in economic mode or maximum capacity mode. The first regulating valve 17 and the second regulating valve 18 can be controlled to make the indoor heat exchanger 5 in parallel flow state.

[0067] When the ambient temperature T < 30℃ and the compressor speed N ≥ 6000 r / min, the system is operating in economic mode. The first regulating valve 17 and the second regulating valve 18 are controlled to make the indoor heat exchanger 5 in parallel flow mode. When the system is operating in maximum capacity mode, the first regulating valve 17 and the second regulating valve 18 are controlled to make the indoor heat exchanger 5 in series flow mode.

[0068] When the ambient temperature T≥30℃ and the compressor speed N<6000r / min, the system is operating in economic mode. The first regulating valve 17 and the second regulating valve 18 are controlled to make the indoor heat exchanger 5 in parallel flow state. When the system is operating in maximum capacity mode, the first regulating valve 17 and the second regulating valve 18 are controlled to make the indoor heat exchanger 5 in series flow state.

[0069] When the ambient temperature T ≥ 30℃ and the compressor speed N ≥ 6000 r / min, if the supply air temperature T air When the temperature is ≥8℃, the system operates in economic mode, controlling the first regulating valve 17 and the second regulating valve 18 to make the indoor heat exchanger 5 flow in parallel; when the system operates in maximum capacity mode, controlling the first regulating valve 17 and the second regulating valve 18 to make the indoor heat exchanger 5 flow in series.

[0070] When the ambient temperature T ≥ 30℃ and the compressor speed N ≥ 6000 r / min, if the supply air temperature T air When the temperature is below 8℃ and the system is operating in maximum capacity mode, the first regulating valve 17 and the second regulating valve 18 are controlled to keep the indoor heat exchanger 5 in a series flow state.

[0071] In heating mode, the system always operates at maximum capacity, controlling the first regulating valve 17 and the second regulating valve 18 to keep the indoor heat exchanger 5 in a series flow state.

[0072] In defrost and defog mode, adjust the system to either cooling or heating mode according to the required cold or warm air. Normally, when the temperature difference between the evaporation temperature and the dew point temperature is greater than 5°C, control the opening of the first regulating valve 17 and the second regulating valve 18 to allow the indoor heat exchanger 5 to enter a parallel flow state; when the temperature difference between the evaporation temperature and the dew point temperature is less than or equal to 5°C, control the first regulating valve 17 and the second regulating valve 18 to allow the indoor heat exchanger 5 to enter a series flow state.

[0073] In heating mode, during series operation, air temperature sensors T1 and T2 are installed in the middle of the first zone 201 and the third zone 203 of the indoor heat exchanger 5. When the temperature difference between T1 and T2 exceeds the value m, if the compressor speed is less than 6000 r / min, the first regulating valve 17 and the second regulating valve 18 will rotate by an angle k° to alleviate the unevenness of the outlet air temperature and increase the comfort of personnel. The values ​​of m and k can be calibrated according to actual conditions, and it is recommended to take values ​​of 5 and 10 respectively.

[0074] Depending on actual needs, unidirectional flow devices and baffles can be set up in 2n sets. After replacing them with regulating valves, regulating valves and baffles can also be set up in 2n sets, where n ranges from 1 to 5. The baffles divide the heat exchange channel into 2n+1 areas, which can easily meet the heating requirements of different systems.

[0075] As is known from common technical knowledge, this invention can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative in all respects and are not the only ones. All modifications within the scope of this invention or its equivalents are included in this invention.

Claims

1. A control method for a carbon dioxide heat pump air conditioning system for vehicle thermal management that combines cooling and heating, characterized in that, The vehicle thermal management carbon dioxide heat pump air conditioning system that combines cooling and heating includes an indoor heat exchanger and a compressor. The indoor heat exchanger is a vehicle thermal management carbon dioxide heat pump air conditioning heat exchanger that combines cooling and heating. The vehicle thermal management carbon dioxide heat pump air conditioning heat exchanger that combines cooling and heating includes: a first port (9), a second port (10), a first main manifold (11), a second main manifold (12), and a heat exchange channel. The first port (9) is connected to the first main manifold (11), the second port (10) is connected to the second main manifold (12), the first main manifold (11) is connected to one end of the heat exchange channel, and the second main manifold (12) is connected to the other end of the heat exchange channel; The first main manifold (11) and the second main manifold (12) are respectively provided with n on / off adjustment structures, where n is a positive integer; the heat exchange channel is divided into 2n+1 regions, and by controlling the on / off state of the 2n on / off adjustment structures, the 2n+1 regions can be in a series flow state or a parallel flow state; the on / off adjustment structure is a regulating valve, and the control method is: In the cooling mode, the refrigerant enters the heat exchanger from the first port (9) and flows out of the heat exchanger from the second port (10). All control valves are open, and the 2n+1 regions of the heat exchange channel are in parallel flow state. Alternatively, all control valves are closed, and the 2n+1 regions of the heat exchange channel are in series flow state. In heating mode, the refrigerant enters the heat exchanger from the second port (10) and flows out of the heat exchanger from the first port (9). All control valves are open, and the 2n+1 regions of the heat exchange channel are in parallel flow state. Alternatively, all control valves are closed, and the 2n+1 regions of the heat exchange channel are in series flow state. The system operates in two modes: economic mode and maximum capacity mode. In cooling mode, the flow state of the 2n+1 zones of the heat exchange channel is controlled according to the following principles: When the ambient temperature T < 30℃ and the compressor speed N < 6000 r / min, all control and regulating valves are open, so that the 2n+1 regions of the heat exchange channel are in parallel flow state; When the ambient temperature T < 30℃, the compressor speed N ≥ 6000 r / min, and the system is operating in economic mode, all control valves are open, so that the 2n+1 regions of the heat exchange channel are in parallel flow; when the system is operating in maximum capacity mode, all control valves are closed, so that the 2n+1 regions of the heat exchange channel are in series flow. When the ambient temperature T≥30℃, the compressor speed N<6000 r / min, and the system is operating in economic mode, all control valves are open, so that the 2n+1 regions of the heat exchange channel are in parallel flow; when the system is operating in maximum capacity mode, all control valves are closed, so that the 2n+1 regions of the heat exchange channel are in series flow. When the ambient temperature T≥30℃, the compressor rotating speed N≥6000 r / min, and the supply air temperature T air ≥8℃, the system runs in the economic mode, the control regulating valves are opened, and the 2n+1 regions of the heat exchange passage are in parallel flow state; when the system runs in the maximum capacity mode, the control regulating valves are closed, and the 2n+1 regions of the heat exchange passage are in series flow state. When the ambient temperature T ≥ 30℃ and the compressor speed N ≥ 6000 r / min, if the supply air temperature T air When the temperature is below 8℃ and the system is operating in maximum capacity mode, all control and regulating valves are closed, so that the 2n+1 regions of the heat exchange channel are in series flow.

2. The control method for a vehicle thermal management carbon dioxide heat pump air conditioning system that combines cooling and heating as described in claim 1, characterized in that, In heating mode, all control valves are closed, so that the 2n+1 areas of the heat exchange channel are in series flow.

3. The control method for a vehicle thermal management carbon dioxide heat pump air conditioning system that combines cooling and heating as described in claim 2, characterized in that, In heating mode, the air temperatures T1 and T2 of the first and second (n+1)th regions of the heat exchange channel in series flow are collected. When the temperature difference between T1 and T2 exceeds the preset value m, if the compressor speed is less than 6000 r / min, the regulating valve is controlled to rotate by k°.

4. The control method for a vehicle thermal management carbon dioxide heat pump air conditioning system that combines cooling and heating as described in claim 1, characterized in that, In defrost and defogging mode, when the temperature difference between the evaporation temperature and the dew point temperature is greater than 5℃, all control valves are opened, so that the 2n+1 areas of the heat exchange channel are in parallel flow; when the temperature difference between the evaporation temperature and the dew point temperature is less than 5℃, all control valves are closed, so that the 2n+1 areas of the heat exchange channel are in series flow.

5. The control method for a vehicle thermal management carbon dioxide heat pump air conditioning system that combines cooling and heating according to claim 1, characterized in that, The vehicle thermal management carbon dioxide heat pump air conditioner heat exchanger that combines cooling and heating also includes partitions. There are 2n partitions, which extend from one end of the heat exchange channel to the other end. The 2n partitions are arranged in parallel and divide the heat exchange channel into 2n+1 regions. The on / off adjustment structure is arranged in a one-to-one correspondence with the partition, and the two on / off adjustment structures corresponding to the two adjacent partitions are located in the first main collector pipe (11) and the second main collector pipe (12), respectively.

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