Dual heat source air source thermal management system and control method thereof

Abstract

The application discloses a double-heat-source air-source thermal management system and a control method thereof. The thermal management system comprises an air conditioner system, a cooling system and a controller. The air conditioner system comprises a condensing flow path, a first evaporating flow path, a second evaporating flow path and a first valve structure. The condensing flow path comprises a compressor and a first heat exchanger, and the first heat exchanger inlet is connected to the compressor outlet. The first evaporating flow path and the second evaporating flow path inlet and outlet are connected to the first heat exchanger outlet and the compressor inlet respectively through the first valve structure. The first valve structure, the first expansion valve and the second expansion valve are electrically connected to the controller, and the controller is used for controlling the first valve structure, the first expansion valve and the second expansion valve to act, so that the air conditioner system runs in a heat pump mode or a defrosting mode. The application has the advantages that the problem of frost formation on the surface of the external heat exchanger can be solved, the effect of heat absorption of the external heat exchanger from the environment is enhanced, and the thermal management energy consumption is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle thermal management, in particular to a dual-heat-source air-source thermal management system and a control method thereof. BACKGROUND

[0002] The direct heat pump system (heat absorption side) refers to a system that can directly absorb heat from the environment by using an EXV (electronic expansion valve) + OHX / OHEX (external heat exchanger). The indirect heat pump system refers to a system that indirectly absorbs heat from an LTR (front-end low-temperature radiator) by using an EXV (electronic expansion valve) and a Chiller (battery cooler). Although the direct heat pump system has higher energy efficiency than the indirect heat pump system, the direct heat pump system (heat absorption side) has three problems: the OHX is prone to frost formation in low-temperature environments (around -5°C, high-humidity environment), which hinders air-source heat absorption; in low-temperature environments below 0°C, the external heat exchanger has low heat absorption efficiency, high thermal management energy consumption, and serious range degradation when there is no electric drive waste heat (before the vehicle starts in cold conditions); and the external heat exchanger requires an additional EXV1, which is costly.

[0003] In Figure 1 The thermal management system shown in the figure has a single PTC (PTC heater) that uses coolant circulation to indirectly heat the refrigerant cycle of the battery cooler and ultimately heat the passenger compartment. On the one hand, the thermal management system uses one five-way water valve (5WV) + one three-way water valve (3WV). When the battery has a high SOC and the water temperature is not too low (> -20°C), only the passenger compartment needs to be heated or the passenger compartment needs to be heated preferentially, and the battery does not need to be heated (bypassing is required). However, this architecture cannot achieve this function due to the series connection of the water pump / PTC / battery, resulting in slow passenger compartment heating (slow battery heating / diversion) in low-temperature environments (e.g., -20°C), which cannot meet the demand for rapid passenger compartment temperature rise. The thermal management system uses two electronic water valves: one five-way valve + one three-way valve, which has more parts and higher cost. On the other hand, the expansion valve EXV1 at the inlet of the external heat exchanger (OHX) of the thermal management system requires the use of a large-diameter expansion valve, which is costly.

[0004] In addition, for electric vehicles, the serious range degradation in winter is also a major pain point. It is of great significance to develop a thermal management solution compatible with a heat pump system using integrated means and reduce the energy consumption of the thermal management system through multi-functional mode switching. SUMMARY

[0005] In order to solve at least one of the above technical problems, the present application provides a dual-heat-source air-source thermal management system and a control method thereof, which controls the first valve structure, the first expansion valve and the second expansion valve to act through a controller, so that the air conditioning system operates in a heat pump mode or a defrosting mode, and realizes dual-heat-source air-source heating of the passenger cabin and defrosting of the external heat exchanger in a low-temperature environment.

[0006] The present application solves the technical problems by adopting the following technical solutions:

[0007] The dual-heat-source air-source thermal management system comprises an air conditioning system, a cooling system and a controller.

[0008] The air conditioning system comprises a condensing flow path, a first evaporating flow path, a second evaporating flow path and a first valve structure; the condensing flow path comprises a compressor and a first heat exchanger, the first heat exchanger inlet is connected to the compressor outlet; the first evaporating flow path comprises a first expansion valve and an external heat exchanger, one interface of the external heat exchanger is connected to the first expansion valve outlet; the second evaporating flow path comprises a second expansion valve and a second heat exchanger, the second heat exchanger comprises a refrigerant-side flow channel and a liquid-side flow channel which are arranged in isolation, the second heat exchanger refrigerant-side flow channel inlet is connected to the second expansion valve outlet; the inlets and outlets of the first evaporating flow path and the second evaporating flow path are connected to the first heat exchanger outlet and the compressor inlet respectively through the first valve structure;

[0009] The cooling system comprises a third heat exchanger, the third heat exchanger is used for heat exchange with the environment, and the third heat exchanger and the liquid-side flow channel of the second heat exchanger can be arranged in series in a circulating loop;

[0010] The first valve structure, the first expansion valve and the second expansion valve are electrically connected to the controller, and the controller is used for controlling the first valve structure, the first expansion valve and the second expansion valve to act, so that the air conditioning system operates in a heat pump mode or a defrosting mode.

[0011] Further, when the air conditioning system operates in the heat pump mode, the controller controls the first valve structure to act to arrange the first evaporating flow path in parallel with the second evaporating flow path, and controls the first expansion valve and the second expansion valve to be opened, so that the external heat exchanger absorbs heat from the environment;

[0012] When the air conditioning system operates in the defrosting mode, the controller controls the first valve structure to act to connect the two interfaces of the external heat exchanger to the first heat exchanger outlet and the second expansion valve inlet respectively, and controls the first expansion valve to be closed and the second expansion valve to be opened, so that the external heat exchanger dissipates heat to the environment.

[0013] Further, the first valve structure comprises a first control valve S1, a second control valve S2, a third control valve S3 and a fourth control valve S4.

[0014] The first control valve S1 is arranged between the first heat exchanger outlet and the split point A of the first evaporation flow path and the second evaporation flow path;

[0015] The second control valve S2 is arranged in the first evaporation flow path and between the external heat exchanger and the compressor inlet;

[0016] One end of the third control valve S3 is connected between the external heat exchanger and the second control valve S2, and the other end is connected between the first control valve S1 and the split point A of the first evaporation flow path and the second evaporation flow path, and one end of the fourth control valve S4 is connected between the first expansion valve and the external heat exchanger, and the other end is connected between the first control valve S1 and the first heat exchanger outlet; or,

[0017] One end of the third control valve S3 is connected between the external heat exchanger and the second control valve S2, and the other end is connected between the first control valve S1 and the first heat exchanger outlet, and one end of the fourth control valve S4 is connected between the first expansion valve and the external heat exchanger, and the other end is connected between the first control valve S1 and the split point A of the first evaporation flow path and the second evaporation flow path.

[0018] Further, when one end of the third control valve S3 is connected between the first control valve S1 and the split point A of the first evaporation flow path and the second evaporation flow path, the third control valve S3 is arranged as a first one-way valve, and the flow direction is arranged from between the external heat exchanger and the second control valve S2 to between the first control valve S1 and the split point A of the first evaporation flow path and the second evaporation flow path;

[0019] When one end of the fourth control valve S4 is connected between the first control valve S1 and the split point A of the first evaporation flow path and the second evaporation flow path, the fourth control valve S4 is arranged as a first one-way valve, and the flow direction is arranged from between the first expansion valve and the external heat exchanger to between the first control valve S1 and the split point A of the first evaporation flow path and the second evaporation flow path.

[0020] Further, the first evaporation flow path is provided with a second one-way valve and is arranged between the second control valve S2 and the compressor inlet, and the flow direction is arranged from the second control valve S2 to the compressor, preventing the second control valve S2 from leaking and causing the refrigerant to migrate to the external heat exchanger.

[0021] Further, the air conditioning system further comprises a third evaporation flow path, the third evaporation flow path comprising a third expansion valve and an evaporator, the inlet of the evaporator being connected to the outlet of the third expansion valve; the inlet and the outlet of the third evaporation flow path are connected to the first heat exchanger outlet and the compressor inlet, respectively;

[0022] The third expansion valve is arranged as a thermal expansion valve, and the first valve structure further comprises a fifth control valve S5 arranged in the third evaporation flow path and located at the inlet of the third expansion valve, and the fifth control valve S5 is electrically connected with the controller.

[0023] The third expansion valve is arranged as an electronic expansion valve, and the third expansion valve is electrically connected with the controller.

[0024] Further, the air conditioning system comprises a liquid storage tank arranged between the outlet of the first control valve S1 and the branch point A of the first evaporation flow path and the second evaporation flow path, which can adjust the refrigerant flow for the air conditioning circulation system.

[0025] Further, the cooling system comprises a first cooling flow path, a second cooling flow path, a third cooling flow path and a fourth cooling flow path connected with the second valve structure, the first cooling flow path comprises an electric drive module cooling device and a first pump arranged in series, the electric drive module cooling device is used for heat exchange with the electric drive module; the third heat exchanger is arranged in the second cooling flow path; the third cooling flow path comprises a battery cooling device used for heat exchange with the battery; the liquid side flow channel of the second heat exchanger is arranged in the fourth cooling flow path, and the liquid side flow channel of the second heat exchanger is arranged in series with a second pump; the second valve structure is electrically connected with the controller, and the controller can control the second valve structure to act to arrange the second cooling flow path in series with the fourth cooling flow path.

[0026] Further, a dual-heat-source air source thermal management control method is provided, which is applied to the thermal management system in any one of the above aspects, and is executed by the controller and comprises the following steps.

[0027] In step 100, when the passenger compartment sends a heating request, the environmental temperature is greater than or equal to a threshold T1, the difference K1 between the environmental temperature and the saturation temperature corresponding to the outlet pressure of the external heat exchanger is less than a threshold T2, or the difference K2 between the target air outlet temperature of the air conditioning box and the actual air outlet temperature is less than a threshold T3, the controller controls the air conditioning system to run in a heat pump mode: controls the first valve structure to act to arrange the first evaporation flow path in parallel with the second evaporation flow path, and controls the first expansion valve and the second expansion valve to open, so that the external heat exchanger absorbs heat from the environment.

[0028] In step 200, when the difference K1 between the environmental temperature and the saturation temperature corresponding to the outlet pressure of the external heat exchanger is greater than or equal to the threshold T2, or the difference K2 between the target air outlet temperature of the air conditioning box and the actual air outlet temperature is greater than or equal to the threshold T3, the controller controls the air conditioning system to run in a defrosting mode: controls the first valve structure to act to connect the two interfaces of the external heat exchanger to the outlet of the first heat exchanger and the inlet of the second expansion valve respectively, controls the first expansion valve to close and the second expansion valve to open, so that the external heat exchanger dissipates heat to the environment.

[0029] Step 300, defrost mode running time t, return to step 100;

[0030] Preferably, the threshold T1 is set to one of -15~0℃, the threshold T2 is set to one of 8~12℃; the threshold T3 is set to one of 8~15℃; the running time t is set to 1~5min.

[0031] Further, the heat management control method further comprises a first valve structure control method, when the first valve structure comprises a first control valve S1, a second control valve S2, a third control valve S3 and a fourth control valve S4, the control method of the first valve structure comprises:

[0032] When the controller controls the air conditioning system to run in heat pump mode, the first control valve S1, the second control valve S2, the first expansion valve and the second expansion valve are opened, and the third control valve S3 and the fourth control valve S4 are closed;

[0033] When the controller controls the air conditioning system to run in defrost mode, the third control valve S3, the fourth control valve S4 and the second expansion valve are opened, and the first control valve S1, the second control valve S2 and the first expansion valve are closed.

[0034] Further, when the air conditioning system comprises a third evaporation flow path, the third expansion valve is set as a thermal expansion valve, and the first valve structure further comprises a fifth control valve S5, the heat management control method further comprises: when the passenger compartment issues a refrigeration request, the controller controls the air conditioning system to run in refrigeration mode, controls the third control valve S3, the fourth control valve S4, the fifth control valve S5 and the second expansion valve to be opened, and controls the first control valve S1, the second control valve S2 and the first expansion valve to be closed.

[0035] When the air conditioning system comprises a third evaporation flow path, the third expansion valve is set as an electronic expansion valve, the heat management control method further comprises: when the passenger compartment issues a refrigeration request, the controller controls the air conditioning system to run in refrigeration mode, controls the third control valve S3, the fourth control valve S4, the second expansion valve and the third expansion valve to be opened, and controls the first control valve S1, the second control valve S2 and the first expansion valve to be closed.

[0036] Compared with the prior art, the beneficial effects of the present application are:

[0037] (1) By controlling the first valve structure, the first expansion valve and the second expansion valve with the controller, the switching of the heat pump mode and the defrost mode of the air conditioning system in a low temperature environment can be realized, the problem of frost formation on the surface of the external heat exchanger is solved, the effect of the external heat exchanger absorbing heat from the environment is enhanced, and at the same time, the low temperature radiator absorbs heat from the environment, realizing double heat source air source heating, greatly improving the air source heating effect and reducing the heat management energy consumption.

[0038] (2) The first valve structure is arranged in a certain way, and the controller controls the action of the first valve structure, so that the refrigerant enters from the upper part of the external heat exchanger when the air conditioning system runs in the defrosting mode and the refrigerating mode, and the refrigerant enters from the lower part of the external heat exchanger when the air conditioning system runs in the heat pump mode, so that the direction of the refrigerant entering the external heat exchanger is different when the air conditioning system runs in the refrigerating mode and the heat pump mode, the system resistance can be reduced in the two running modes, the heat exchange effect of the external heat exchanger is enhanced, and the performance of the air conditioning system is better. BRIEF DESCRIPTION OF DRAWINGS

[0039] For better understanding of the above and other objects, features, advantages and functions of the present application, reference can be made to the embodiments shown in the drawings. The same reference signs in the drawings refer to the same parts. Those skilled in the art should understand that the drawings are intended to illustrate the preferred embodiments of the present application, and have no limiting effect on the scope of the present application, and the various parts in the drawings are not drawn to scale.

[0040] Figure 1 It is a schematic diagram of a heat management system.

[0041] Figure 2 It is a schematic diagram of an embodiment structure of the air conditioning system of the present application.

[0042] Figure 3 It is a schematic diagram of another embodiment structure of the air conditioning system of the present application.

[0043] Figure 4 It is a schematic diagram of an embodiment structure of the cooling system of the present application.

[0044] In the figure: 1, multi-way valve; 2, second pump; 3, electric drive module cooling device; 4, low-temperature radiator; 5, first pump; 6, PTC heater; 7, battery cooler; 8, battery cooling device; 11, compressor; 12, first heat exchanger; 13, first expansion valve; 14, external heat exchanger; 15, second expansion valve; 16, third expansion valve; 17, evaporator; 18, liquid storage tank. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical scheme and advantages of the present application clearer and more apparent, the following describes exemplary embodiments of the present disclosure in conjunction with the drawings, which include various details of the embodiments of the present disclosure to help understanding, and they should be considered only as exemplary. Therefore, those skilled in the art should realize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Similarly, in order to be clear and concise, the description in the following description omits the description of well-known functions and structures.

[0046] In the description of the present application, it should be noted that the term "comprising" and its variants means open inclusion, i.e. "including but not limited to". The terms "first", "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. The term "and / or" when used to list two or more items means that any one of the listed items can be taken by itself, or any combination of two or more of the listed items can be taken. In addition, in the description of the present application, "a plurality of" means at least two, for example two, three, etc., unless otherwise explicitly and specifically limited.

[0047] The present application provides a dual-heat-source air source heat management system, referring to Figures 2-4 The air conditioning system includes a condensing flow path, a first evaporating flow path, a second evaporating flow path and a first valve structure; the condensing flow path includes a compressor 11 and a first heat exchanger 12, the first heat exchanger 12 is connected to the outlet of the compressor 11, the inlet of the condensing flow path is the inlet of the compressor 11, and the outlet is the outlet of the first heat exchanger 12; the first evaporating flow path includes a first expansion valve 13 and an external heat exchanger 14, one interface of the external heat exchanger 14 is connected to the outlet of the first expansion valve 13, the inlet of the first evaporating flow path is the inlet of the first expansion valve 13, and the outlet is the outlet of the external heat exchanger 14; the second evaporating flow path includes a second expansion valve 15 and a second heat exchanger, the second heat exchanger includes a separate agent-side flow path and a liquid-side flow path, the agent-side flow path of the second heat exchanger is connected to the outlet of the second expansion valve 15, the inlet of the second evaporating flow path is the inlet of the second expansion valve 15, and the outlet is the outlet of the second heat exchanger. The inlets and outlets of the first evaporating flow path and the second evaporating flow path are connected to the outlet of the first heat exchanger 12 and the inlet of the compressor 11 respectively through the first valve structure, i.e. connected to the outlet and inlet of the condensing flow path respectively. The first valve structure, the first expansion valve 13 and the second expansion valve 15 are electrically connected to the controller, and the controller is used to control the action of the first valve structure, the first expansion valve 13 and the second expansion valve 15, so that the air conditioning system operates in heat pump mode or defrosting mode. The first expansion valve 13 can use an electronic expansion valve EXV1, and the second expansion valve 15 can use an electronic expansion valve EXV2, which has high control accuracy.

[0048] The cooling system includes a third heat exchanger, which is used for heat exchange with the environment, and the third heat exchanger and the liquid-side flow path of the second heat exchanger can be arranged in series in a circulation loop.

[0049] The first heat exchanger 12 is provided in the HVAC air conditioning box, which can use an internal condenser (IC) to heat the air in the air conditioning box. The second heat exchanger can use a battery chiller 7, and the third heat exchanger is provided as a low-temperature radiator 4 at the front end of the vehicle. When the low-temperature radiator 4 and the liquid side flow path of the battery chiller 7 are connected in series in a circulation loop, and the low-temperature radiator 4 absorbs heat from the environment, the heat absorbed by the low-temperature radiator 4 from the environment can be transferred to the refrigerant circulation through the battery chiller 7 by circulating the cooling liquid, and finally to the passenger compartment.

[0050] The cooling liquid medium in the cooling system is a liquid mixed by ethylene glycol and water in a certain proportion, or other similar functional liquid medium. The refrigerant medium of the air conditioning system can use R134a (tetrafluoroethane) and R1234yf (2,3,3,3-tetrafluoropropene) and other similar functional refrigerant medium.

[0051] When the air conditioning system operates in the heat pump mode, the controller controls the first valve structure to act to connect the first evaporation flow path in parallel with the second evaporation flow path, and controls the first expansion valve 13 and the second expansion valve 15 to be opened, so that the external heat exchanger 14 absorbs heat from the environment.

[0052] Specifically, refer to Figure 2 and Figure 3The working process of the air source heat management system with double heat sources shown is as follows: the compressor 11 sucks in the low-temperature and low-pressure refrigerant at the outlet of the second heat exchanger and the outlet of the external heat exchanger 14, and compresses it into high-temperature and high-pressure gas. The high-temperature and high-pressure refrigerant flowing out of the compressor 11 is discharged through the first heat exchanger 12 to release heat and finally heat the passenger compartment. The refrigerant flowing out of the first heat exchanger 12 flows through the first evaporation flow path and the second evaporation flow path through the first valve structure respectively. The refrigerant is sucked into the compressor 11 after being evaporated and absorbing heat in the second heat exchanger and the external heat exchanger 14, forming a heat pump cycle. When the refrigerant flows through the first evaporation flow path, it first passes through the first expansion valve 13 to throttle and become low-temperature and low-pressure, and then flows through the external heat exchanger 14. The refrigerant in the external heat exchanger 14 absorbs heat from the environment to evaporate into low-temperature and low-pressure refrigerant gas which is sucked into the compressor 11. When the refrigerant flows through the second evaporation flow path, it first passes through the second expansion valve 15 to throttle and become low-temperature and low-pressure, and then flows through the second heat exchanger. The refrigerant in the second heat exchanger absorbs heat from the cooling liquid to evaporate into low-temperature and low-pressure refrigerant gas which is sucked into the compressor 11. The heat of the environment exchanged with the external heat exchanger 14 and the heat of the cooling liquid exchanged with the second heat exchanger are circulated to the first heat exchanger 12 and finally used for heating the passenger compartment, so as to transfer the heat in the air and the heat in the cooling liquid to the passenger compartment through the heat pump cycle. The heat of the cooling liquid exchanged with the second heat exchanger includes the heat exchanged between the low-temperature radiator 4 and the environment, that is, the double heat source air source heating is realized. In this way, the external heat exchanger 14 and the low-temperature radiator 4 simultaneously absorb heat from the air, greatly improving the air source heating effect, reducing the energy consumption of heat management, and improving the endurance of the vehicle.

[0053] In a low-temperature and high-humidity environment, when the external heat exchanger 14 surface is frosted, the air source heat absorption of the external heat exchanger 14 is blocked, and the air conditioning system runs the defrosting mode. The controller controls the first valve structure to connect the two interfaces of the external heat exchanger 14 to the outlet of the first heat exchanger 12 and the inlet of the second expansion valve 15 respectively, controls the first expansion valve 13 to close and the second expansion valve 15 to open, and makes the external heat exchanger 14 dissipate heat to the environment.

[0054] Specifically, reference is made to Figure 2 and Figure 3The dual-heat-source air-source thermal management system shown operates as follows in defrost mode: Compressor 11 draws in low-temperature, low-pressure refrigerant from the outlet of the second heat exchanger, compresses it into high-temperature, high-pressure gas, and the high-temperature, high-pressure refrigerant flowing out of compressor 11 releases heat through the first heat exchanger 12, ultimately heating the passenger compartment. The refrigerant flowing out of the first heat exchanger 12 then passes through the first valve structure, first flowing through the external heat exchanger 14, and then through the second evaporation path. The refrigerant's higher temperature when flowing through the external heat exchanger 14 heats it, melting the frost on its surface. The refrigerant flowing out of the external heat exchanger 14 then passes through the second expansion valve 15, becoming low-temperature, low-pressure, and then flows through the second heat exchanger. The refrigerant in the second heat exchanger absorbs heat from the coolant and evaporates into low-temperature, low-pressure refrigerant gas, which is then drawn into compressor 11. During defrost mode, the air conditioning system simultaneously forms a heat pump cycle, which can heat the passenger compartment through the second heat exchanger, providing continuous heating in low-temperature environments.

[0055] In some embodiments, such as Figure 2 As shown, the first valve structure includes a first control valve S1, a second control valve S2, a third control valve S3, and a fourth control valve S4. The first control valve S1 is located between the outlet of the first heat exchanger 12 and the branch point A of the first evaporation flow path and the second evaporation flow path. The second control valve S2 is located in the first evaporation flow path and between the external heat exchanger 14 and the inlet of the compressor 11. One end of the third control valve S3 is connected between the external heat exchanger 14 and the second control valve S2, and the other end is connected between the first control valve S1 and the branch point A of the first evaporation flow path and the second evaporation flow path. One end of the fourth control valve S4 is connected between the first expansion valve 13 and the external heat exchanger 14, and the other end is connected between the outlet of the first heat exchanger 12 and the first control valve S1, forming a first configuration of the first valve structure.

[0056] In this embodiment, when the air conditioning system operates in heat pump mode, the first control valve S1, the second control valve S2, the first expansion valve 13, and the second expansion valve 15 are open, while the third control valve S3 and the fourth control valve S4 are closed. When the air conditioning system operates in defrost mode, the third control valve S3, the fourth control valve S4, and the second expansion valve 15 are open, while the first control valve S1, the second control valve S2, and the first expansion valve 13 are closed. The circulation loop of the air conditioning system operating in heat pump mode is: compressor 11 → first heat exchanger 12 → first control valve S1 → (first expansion valve 13 → external heat exchanger 14 → second control valve S2) and (second expansion valve 15 → second heat exchanger) → compressor 11. The circulation loop of the air conditioning system operating in defrost mode is: compressor 11 → first heat exchanger 12 → fourth control valve S4 → external heat exchanger 14 → third control valve S3 → second expansion valve 15 → second heat exchanger → compressor 11. In this embodiment, the refrigerant flows through the same inlet and outlet of the external heat exchanger 14 in both defrost mode and heat pump mode, and the flow direction within the external heat exchanger 14 is the same. For example, in heat pump mode, the refrigerant enters from the bottom and exits from the top of the external heat exchanger 14, and in defrost mode, the refrigerant still enters from the bottom and exits from the top of the external heat exchanger 14.

[0057] In some embodiments, such as Figure 3 As shown, the first valve structure includes a first control valve S1, a second control valve S2, a third control valve S3, and a fourth control valve S4. The first control valve S1 is located between the outlet of the first heat exchanger 12 and the branch point A of the first evaporation flow path and the second evaporation flow path. The second control valve S2 is located in the first evaporation flow path and between the external heat exchanger 14 and the inlet of the compressor 11. One end of the third control valve S3 is connected between the external heat exchanger 14 and the second control valve S2, and the other end is connected between the outlet of the first heat exchanger 12 and the first control valve S1. One end of the fourth control valve S4 is connected between the first expansion valve 13 and the external heat exchanger 14, and the other end is connected between the first control valve S1 and the branch point A of the first evaporation flow path and the second evaporation flow path, forming a second configuration of the first valve structure.

[0058] In this embodiment, when the air conditioning system operates in the heat pump mode, the first control valve S1, the second control valve S2, the first expansion valve 13 and the second expansion valve 15 are opened, and the third control valve S3 and the fourth control valve S4 are closed; when the air conditioning system operates in the defrosting mode, the third control valve S3, the fourth control valve S4 and the second expansion valve 15 are opened, and the first control valve S1, the second control valve S2 and the first expansion valve 13 are closed. The circulation loop of the air conditioning system operating in the heat pump mode is: the compressor 11→the first heat exchanger 12→the first control valve S1→(the first expansion valve 13→the external heat exchanger 14→the second control valve S2) and (the second expansion valve 15→the second heat exchanger)→the compressor 11. The circulation loop of the air conditioning system operating in the defrosting mode is: the compressor 11→the first heat exchanger 12→the third control valve S3→the external heat exchanger 14→the fourth control valve S4→the second expansion valve 15→the second heat exchanger→the compressor 11. In this embodiment, the defrosting mode and the heat pump mode are opposite in the inlet and outlet of the external heat exchanger 14, and the flow directions in the external heat exchanger 14 are opposite. For example, in the heat pump mode, the refrigerant enters the lower part of the external heat exchanger 14 and flows out from the upper part, and in the defrosting mode, the refrigerant enters the upper part of the external heat exchanger 14 and flows out from the lower part.

[0059] According to the needs, the first control valve S1, the second control valve S2, the third control valve S3 and the fourth control valve S4 can use on-off valves such as ball valves, electromagnetic valves, butterfly valves, gate valves, etc. which can be controlled by a controller.

[0060] When the air conditioning system operates in the heat pump mode, the third control valve S3 and the fourth control valve S4 are closed, in order to prevent the third control valve S3 and the fourth control valve S4 from leaking and causing the refrigerant to migrate to the external heat exchanger 14, thereby reducing the heat absorption effect of the external heat exchanger 14. When one end of the third control valve S3 is connected between the first control valve S1 and the shunt point A of the first evaporative flow path and the second evaporative flow path, the third control valve S3 is set as a first check valve CV1, and the flow direction is set to flow from between the external heat exchanger 14 and the second control valve S2 to between the first control valve S1 and the shunt point A of the first evaporative flow path and the second evaporative flow path; when one end of the fourth control valve S4 is connected between the first control valve S1 and the shunt point A of the first evaporative flow path and the second evaporative flow path, the fourth control valve S4 is set as a first check valve CV1, and the flow direction is set to flow from between the first expansion valve 13 and the external heat exchanger 14 to between the first control valve S1 and the shunt point A of the first evaporative flow path and the second evaporative flow path.

[0061] When the air conditioning system runs the defrost mode and the refrigeration mode, the second control valve S2 is closed. In order to prevent the refrigerant from migrating to the external heat exchanger 14 due to leakage of the second control valve S2, affecting the operation effect of the air conditioning system, a second check valve CV2 can be arranged in the first evaporation flow path, and arranged between the second control valve S2 and the inlet of the compressor 11, and the flow direction is arranged from the second control valve S2 to the compressor 11.

[0062] The air conditioning system further comprises a third evaporation flow path, the third evaporation flow path comprises a third expansion valve 16 and an evaporator 17, and the inlet of the evaporator 17 is connected to the outlet of the third expansion valve 16; the inlet and the outlet of the third evaporation flow path are respectively connected to the outlet of the first heat exchanger 12 and the inlet of the compressor 11.

[0063] The evaporator 17 is arranged in the air conditioning box, and the third expansion valve 16 can directly use an electronic expansion valve EXV3. The third expansion valve 16 is electrically connected with the controller, so as to improve the control precision. The third expansion valve 16 can also use a thermal expansion valve TXV. The first valve structure further comprises a fifth control valve S5, which is arranged in the third evaporation flow path and located at the inlet of the third expansion valve 16. The fifth control valve S5 is electrically connected with the controller. By combining the third expansion valve 16 and the fifth control valve S5, the cost is reduced. When the controller controls the third expansion valve EXV3 or the fifth control valve S5 to open, the air conditioning system can run the refrigeration mode, and the air in the air conditioning box is cooled by the evaporator 17 to provide cold energy for the passenger cabin. When the air conditioning system runs the refrigeration mode, the third control valve S3, the fourth control valve S4, the fifth control valve S5 (or the third expansion valve EXV3) and the second expansion valve 15 are opened, and the first control valve S1, the second control valve S2 and the first expansion valve 13 are closed.

[0064] As shown in Figure 2 When the first valve structure is arranged in the first configuration, the circulating loop of the air conditioning system running the refrigeration mode is: the compressor 11→the first heat exchanger 12→the fourth control valve S4→the external heat exchanger 14→the third control valve S3→(the second expansion valve 15→the second heat exchanger) and (the fifth control valve S5→the third expansion valve 16→the evaporator 17)→the compressor 11. As shown in Figure 3 When the first valve structure is arranged in the second configuration, the circulating loop of the air conditioning system running the refrigeration mode is: the compressor 11→the first heat exchanger 12→the third control valve S3→the external heat exchanger 14→the fourth control valve S4→(the second expansion valve 15→the second heat exchanger) and (the fifth control valve S5→the third expansion valve 16→the evaporator 17)→the compressor 11.

[0065] When the air conditioning system operates in the heat pump mode, the refrigerant flowing out of the first heat exchanger 12 becomes gas-liquid two-phase refrigerant after throttling by the first expansion valve 13, and then enters the external heat exchanger 14; when the air conditioner operates in the defrosting mode, the liquid or gas-liquid two-phase refrigerant flowing out of the first heat exchanger 12 enters the external heat exchanger 14; when the air conditioner operates in the refrigeration mode, the gaseous refrigerant flowing out of the first heat exchanger 12 does not exchange heat, directly enters the external heat exchanger 14. The gaseous refrigerant entering the external heat exchanger 14 has large resistance and requires large heat exchange area, the liquid refrigerant entering the external heat exchanger 14 has small resistance and requires small heat exchange area, preferably, the gaseous refrigerant can enter the external heat exchanger 14 from the upper part, the liquid refrigerant and the gas-liquid two-phase refrigerant can enter the external heat exchanger 14 from the lower part, thereby reducing system resistance and enhancing heat exchange effect. When the air conditioning system operates in the defrosting mode and the refrigeration mode, the direction of entering the external heat exchanger 14 is the same, the defrosting mode is short-time operation, preferably, the refrigeration effect is met, and the defrosting effect is not affected. When the air conditioning system operates in the defrosting mode and the refrigeration mode, it is preferable to enter from the upper part of the external heat exchanger 14 to the lower part and flow out, and when the air conditioning system operates in the heat pump mode, it is preferable to enter from the lower part of the external heat exchanger 14 to the upper part and flow out, preferably, the first valve structure is set to the second configuration, and the air conditioning system has better performance.

[0066] In order to prevent the refrigerant from migrating to the evaporator 17, for example, when the second heat exchanger inlet pressure is high, the refrigerant will flow from the second heat exchanger outlet to the third evaporation flow path, at this time, a third one-way valve CV3 can be arranged on the third evaporation flow path, and the third one-way valve CV3 is arranged between the evaporator 17 and the compressor 11.

[0067] It can be understood that the condensation flow path is the main pipe of the refrigerant circulation, in some embodiments, the condensation flow path, the first evaporation flow path, the second evaporation flow path and the third evaporation flow path can be connected through a four-way joint, at this time, the four-way joint is the branch point A of the first evaporation flow path, the second evaporation flow path and the third evaporation flow path; in some embodiments, the inlet pipelines of the first evaporation flow path, the second evaporation flow path and the third evaporation flow path can be connected to the main pipeline of the refrigerant respectively, at this time, the branch point of the evaporation flow path close to the outlet of the first heat exchanger 12 is the branch point A of the first evaporation flow path, the second evaporation flow path and the third evaporation flow path.

[0068] In some embodiments, the air conditioning system comprises a liquid storage tank 18, which is arranged between the outlet of the first control valve S1 and the branch point A of the first evaporation flow path and the second evaporation flow path. The liquid storage tank 18 is arranged on the high-pressure side main pipeline of the air conditioning system, and over-cooled refrigerant is stored in the liquid storage tank 18, which can adjust the refrigerant flow for the air conditioning circulation system, maintain stable operation of the system, separate the refrigerant, prevent the compressor 11 from being liquid struck, and reduce the cost of the air conditioning system. The liquid storage tank 18 is arranged between the outlet of the first control valve S1 and the branch point A of the first evaporation flow path and the second evaporation flow path, so that the air conditioning system can normally operate in the heat pump mode, the defrosting mode and the refrigeration mode.

[0069] Of course, the air conditioning system can also comprise a gas-liquid separator, which can be arranged on the low-pressure side of the air conditioning system, specifically at the inlet of the compressor 11, to separate the refrigerant and prevent the compressor 11 from being liquid struck.

[0070] In some embodiments, referring to Figure 4 As shown in the figure, the cooling system comprises a first cooling flow path, a second cooling flow path, a third cooling flow path and a fourth cooling flow path connected to a second valve structure, the first cooling flow path comprises an electric drive module cooling device 3 and a first pump 5 arranged in series, the electric drive module cooling device 3 is used for heat exchange with the electric drive module; the third heat exchanger is arranged in the second cooling flow path; the third cooling flow path comprises a battery cooling device 8 used for heat exchange with the battery; the liquid side flow channel of the second heat exchanger is arranged in the fourth cooling flow path, and the liquid side flow channel of the second heat exchanger is arranged in series with a second pump 2; the second valve structure is electrically connected with a controller, and the controller can control the second valve structure to act to arrange the second cooling flow path in series with the fourth cooling flow path.

[0071] The cooling system structure is not limited in the present application, as long as the second cooling flow path and the fourth cooling flow path are communicated, the heat absorbed by the low-temperature radiator 4 is transferred to the battery cooler 7, and then to the passenger compartment, and then combined with the heat absorption of the external heat exchanger 14 to realize the double-heat-source air-source heat pump heating.

[0072] Exemplarily, the second valve structure comprises a multi-way valve 1, the interfaces of the multi-way valve 1 are arranged as eight, and the inlets and outlets of the first cooling flow path, the second cooling flow path, the third cooling flow path and the fourth cooling flow path are respectively connected to different interfaces of the multi-way valve 1. As Figure 4As shown, the multi-way valve 1 includes a C1 interface, a C2 interface, a C3 interface, a C4 interface, a C5 interface, a C6 interface, a C7 interface and a C8 interface; the inlet and outlet of the first cooling flow path are connected to the C1 interface and the C8 interface respectively, the inlet and outlet of the second cooling flow path are connected to the C3 interface and the C2 interface respectively, the inlet and outlet of the third cooling flow path are connected to the C6 interface and the C5 interface respectively, and the inlet and outlet of the fourth cooling flow path are connected to the C4 interface and the C7 interface respectively. The controller controls the multi-way valve 1 to act, and communicates the C7 interface and the C3 interface, so that the low-temperature radiator 4 and the second heat exchanger can be communicated in a circulation loop. The first cooling flow path and / or the third cooling flow path can also be communicated in the circulation loop to recover the waste heat of the electric drive module and the waste heat of the battery. When the second heat exchanger is provided with a PTC heater 6 in series, the cooling liquid can also be heated by the PTC heater 6.

[0073] In another aspect, the application also provides a dual-heat-source air-source thermal management control method, which is applied to the thermal management system of any one of the above aspects, and is executed by a controller and includes the following steps:

[0074] Step 100: When the passenger compartment issues a heating request, the environmental temperature is greater than or equal to a threshold T1, and the difference K1 between the environmental temperature and the saturation temperature corresponding to the outlet pressure of the external heat exchanger 14 is less than a threshold T2, or the difference K2 between the target air outlet temperature of the air conditioning box and the actual air outlet temperature is less than a threshold T3, the controller controls the air conditioning system to run in a heat pump mode: controls the first valve structure to act to connect the first evaporation flow path in parallel with the second evaporation flow path, and controls the first expansion valve 13 and the second expansion valve 15 to open, so that the external heat exchanger 14 absorbs heat from the environment;

[0075] Step 200: When the difference K1 between the environmental temperature and the saturation temperature corresponding to the outlet pressure of the external heat exchanger 14 is greater than or equal to the threshold T2, or the difference K2 between the target air outlet temperature of the air conditioning box and the actual air outlet temperature is greater than or equal to the threshold T3, the controller controls the air conditioning system to run in a defrosting mode: controls the first valve structure to act to connect the two interfaces of the external heat exchanger 14 to the outlet of the first heat exchanger 12 and the inlet of the second expansion valve 15 respectively, and controls the first expansion valve 13 to close and the second expansion valve 15 to open, so that the external heat exchanger 14 dissipates heat to the environment;

[0076] Step 300: After the defrosting mode runs for a time t, return to step 100.

[0077] When the passenger cabin sends a heating request, and the ambient temperature is greater than or equal to a threshold value T1, the air conditioning system operates in a heat pump mode to heat the passenger cabin, and the low-temperature radiator 4 and the battery cooler 7 are connected in series on the liquid side in a circulation loop. The low-temperature radiator 4 absorbs heat from the environment and transfers it to the passenger cabin. The thermal management system can perform double heat source heating of the external heat exchanger 14 and the low-temperature radiator 4. Preferably, the threshold value T1 is set to one of -15 to 0°C, for example, the threshold value T1 can be set to -15°C, -14°C, -13°C, -12°C, -11°C, -10°C, -9°C, -8°C, -7°C, -6°C, -5°C, -4°C, -3°C, -2°C, -1°C, 0°C, etc.

[0078] For switching between the defrosting mode and the heat pump mode, the switching can be performed according to a difference K1 between the ambient temperature and the saturation temperature corresponding to the outlet pressure of the external heat exchanger 14, or according to a difference K2 between the target air outlet temperature of the air conditioning box and the actual air outlet temperature.

[0079] When the switching is performed according to the difference K1 between the ambient temperature and the saturation temperature corresponding to the outlet pressure of the external heat exchanger 14, a pressure sensor P can be arranged at the inlet of the compressor 11. The outlet pressure of the external heat exchanger 14 is calibrated according to the inlet pressure of the compressor 11. The outlet pressure of the external heat exchanger 14 is obtained according to the actually detected outlet pressure of the compressor 11. The corresponding saturation temperature is obtained according to the outlet pressure of the external heat exchanger 14 (the corresponding relationship between the outlet pressure of the external heat exchanger 14 and the saturation temperature is pre-written in the controller). When the external heat exchanger 14 absorbs heat from the environment, K1 = ambient temperature - saturation temperature. When K1 < threshold value T2, it indicates that the outlet pressure of the external heat exchanger 14 is high, and the heat absorption effect of the external heat exchanger 14 is good. The air conditioning system can normally operate in the heat pump mode. When K1 ≥ threshold value T2, it indicates that the outlet pressure of the external heat exchanger 14 is reduced, and the heat absorption effect of the external heat exchanger 14 is poor. Frosting occurs on the surface of the external heat exchanger 14, and the defrosting mode needs to be operated. Preferably, the threshold value T2 is set to one of 8 to 12°C, for example, the threshold value T2 can be set to 8°C, 8.5°C, 9°C, 9.5°C, 10°C, 10.5°C, 11°C, 11.5°C, or 12°C, etc. Illustratively, the threshold value T2 is set to 9°C. When K1 < 9, the air conditioning system operates in the heat pump mode. When K1 ≥ 9, the air conditioning system operates in the defrosting mode.

[0080] When switching according to the difference K2 between the target air outlet temperature of the air conditioning box and the actual air outlet temperature, the air conditioning runs in the heat pump mode to heat the passenger compartment, the target air outlet temperature of the air conditioning box is high, K2=target air outlet temperature-actual air outlet temperature, when K2

[0081] When the air conditioning system runs in the defrosting mode, the high-temperature refrigerant discharged from the compressor 11 enters the external heat exchanger 14 after passing through the first heat exchanger 12, and the temperature of the refrigerant flowing through the external heat exchanger 14 is still high, which can quickly melt the frost on the surface of the external heat exchanger 14. After the defrosting mode runs for a time t, it can be switched back to the heat pump mode. The running time t of the defrosting mode is set to 1-5 min, for example, the running time t can be set to 1 min, 1.5 min, 2 min, 2.5 min, 3 min, 3.5 min, 4 min, 4.5 min or 5 min, etc.

[0082] The heat management control method further includes a first valve structure control method. When the first valve structure includes a first control valve S1, a second control valve S2, a third control valve S3, and a fourth control valve S4, the control method of the first valve structure includes:

[0083] When the controller controls the air conditioning system to run in the heat pump mode, the first control valve S1, the second control valve S2, the first expansion valve 13, and the second expansion valve 15 are opened, and the third control valve S3 and the fourth control valve S4 are closed.

[0084] When the controller controls the air conditioning system to run in the defrosting mode, the third control valve S3, the fourth control valve S4, and the second expansion valve 15 are opened, and the first control valve S1, the second control valve S2, and the first expansion valve 13 are closed.

[0085] When the air conditioning system comprises a third evaporation flow path, the third expansion valve 16 is set as a thermal expansion valve, and the first valve structure further comprises a fifth control valve S5, the thermal management control method further comprises: when the passenger compartment issues a cooling request, the controller controls the air conditioning system to run in a cooling mode, controls the third control valve S3, the fourth control valve S4, the fifth control valve S5 and the second expansion valve 15 to open, and controls the first control valve S1, the second control valve S2 and the first expansion valve 13 to close.

[0086] When the air conditioning system comprises a third evaporation flow path, the third expansion valve 16 is set as an electronic expansion valve, the thermal management control method further comprises: when the passenger compartment issues a cooling request, the controller controls the air conditioning system to run in a cooling mode, controls the third control valve S3, the fourth control valve S4, the second expansion valve 15 and the third expansion valve 16 to open, and controls the first control valve S1, the second control valve S2 and the first expansion valve 13 to close.

[0087] When the air conditioning system runs in each mode, the opening and closing of each control valve and expansion valve is shown in Table 1:

[0088] Table 1 Opening and closing of control valves and expansion valves in different operating modes of the air conditioning system

[0089]

[0090] By controlling the action of each control valve and each expansion valve through the controller, different operating modes of the air conditioning system can be realized. In a low temperature environment, the problem of frost formation on the surface of the external heat exchanger 14 can be solved, and the effect of the external heat exchanger 14 absorbing heat from the environment is enhanced, and at the same time, the low temperature heat sink 4 absorbs heat from the environment, realizing double heat source air source heating, greatly improving the air source heating effect, and reducing the thermal management energy consumption.

[0091] The above only describes the preferred embodiments of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A dual-heat-source air-source thermal management system, characterized by, The air conditioning system, the cooling system and the controller are included. The air conditioning system includes a condensing flow path, a first evaporating flow path, a second evaporating flow path and a first valve structure; the condensing flow path includes a compressor and a first heat exchanger, an inlet of the first heat exchanger is connected to an outlet of the compressor; the first evaporating flow path includes a first expansion valve and an external heat exchanger, one interface of the external heat exchanger is connected to an outlet of the first expansion valve; the second evaporating flow path includes a second expansion valve and a second heat exchanger, the second heat exchanger includes a separated refrigerant side flow path and a liquid side flow path, an inlet of the refrigerant side flow path of the second heat exchanger is connected to an outlet of the second expansion valve; inlets and outlets of the first evaporating flow path and the second evaporating flow path are connected to an outlet of the first heat exchanger and an inlet of the compressor respectively through the first valve structure; The cooling system includes a third heat exchanger, the third heat exchanger is used for heat exchange with the environment, and the third heat exchanger and the liquid side flow path of the second heat exchanger can be arranged in series in a circulation loop; The first valve structure, the first expansion valve and the second expansion valve are electrically connected with the controller, and the controller is used for controlling actions of the first valve structure, the first expansion valve and the second expansion valve, so that the air conditioning system operates in a heat pump mode or a defrosting mode; When the air conditioning system operates in the heat pump mode, the controller controls the first valve structure to arrange the first evaporating flow path in parallel with the second evaporating flow path, and controls the first expansion valve and the second expansion valve to be opened, so that the external heat exchanger absorbs heat from the environment; When the air conditioning system operates in the defrosting mode, the controller controls the first valve structure to connect two interfaces of the external heat exchanger to the outlet of the first heat exchanger and the inlet of the second expansion valve respectively, controls the first expansion valve to be closed and the second expansion valve to be opened, so that the external heat exchanger radiates heat to the environment.

2. The dual-heat-source air-source thermal management system of claim 1, wherein, The first valve structure includes a first control valve S1, a second control valve S2, a third control valve S3 and a fourth control valve S4; The first control valve S1 is arranged between the outlet of the first heat exchanger and a branch point A of the first evaporating flow path and the second evaporating flow path; The second control valve S2 is arranged in the first evaporating flow path and located between the external heat exchanger and the inlet of the compressor; One end of the third control valve S3 is connected between the external heat exchanger and the second control valve S2, the other end is connected between the first control valve S1 and the branch point A of the first evaporating flow path and the second evaporating flow path, one end of the fourth control valve S4 is connected between the first expansion valve and the external heat exchanger, the other end is connected between the outlet of the first heat exchanger and the first control valve S1; or One end of the third control valve S3 is connected between the external heat exchanger and the second control valve S2, the other end is connected between the outlet of the first heat exchanger and the first control valve S1, one end of the fourth control valve S4 is connected between the first expansion valve and the external heat exchanger, the other end is connected between the first control valve S1 and the branch point A of the first evaporating flow path and the second evaporating flow path.

3. The dual-heat-source air-source thermal management system of claim 2, wherein, When one end of the third control valve S3 is connected between the first control valve S1 and the split point A of the first evaporation flow path and the second evaporation flow path, the third control valve S3 is set as a first one-way valve, and the flow direction is set from between the external heat exchanger and the second control valve S2 to between the first control valve S1 and the split point A of the first evaporation flow path and the second evaporation flow path; When one end of the fourth control valve S4 is connected between the first control valve S1 and the split point A of the first evaporation flow path and the second evaporation flow path, the fourth control valve S4 is set as a first one-way valve, and the flow direction is set from between the first expansion valve and the external heat exchanger to between the first control valve S1 and the split point A of the first evaporation flow path and the second evaporation flow path.

4. The dual-heat-source air-source thermal management system of claim 2 or 3, wherein, The first evaporation flow path is provided with a second one-way valve, which is arranged between the second control valve S2 and the compressor inlet, and the flow direction is set from the second control valve S2 to the compressor.

5. The dual-heat-source air-source thermal management system of claim 2, wherein, The air conditioning system further comprises a third evaporation flow path, which comprises a third expansion valve and an evaporator, and the inlet of the evaporator is connected to the outlet of the third expansion valve; the inlet and the outlet of the third evaporation flow path are connected to the outlet of the first heat exchanger and the inlet of the compressor, respectively; The third expansion valve is set as a thermal expansion valve, and the first valve structure further comprises a fifth control valve S5, which is arranged in the third evaporation flow path and located at the inlet of the third expansion valve, and the fifth control valve S5 is electrically connected to the controller; or, The third expansion valve is set as an electronic expansion valve, and the third expansion valve is electrically connected to the controller.

6. The dual-heat-source air-source thermal management system of claim 2 or 5, wherein, The air conditioning system comprises a liquid storage tank, which is arranged between the outlet of the first control valve S1 and the split point A of the first evaporation flow path and the second evaporation flow path.

7. The dual-heat-source air-source thermal management system of claim 1, wherein, The cooling system comprises a first cooling flow path, a second cooling flow path, a third cooling flow path and a fourth cooling flow path connected to the second valve structure, the first cooling flow path comprises an electric drive module cooling device and a first pump arranged in series, the electric drive module cooling device is used for heat exchange with the electric drive module; the third heat exchanger is arranged in the second cooling flow path; the third cooling flow path comprises a battery cooling device for heat exchange with the battery; the liquid side flow channel of the second heat exchanger is arranged in the fourth cooling flow path, and the liquid side flow channel of the second heat exchanger is provided with a second pump in series; the second valve structure is electrically connected to the controller, and the controller can control the second valve structure to act to arrange the second cooling flow path in series in the fourth cooling flow path.

8. A dual-heat-source air-source thermal management control method, characterized by, The thermal management control method is applied to the thermal management system of any one of claims 1-7, and the thermal management control method is executed by the controller and comprises the following steps: Step 100, when the passenger compartment sends a heating request, the environment temperature is greater than or equal to a threshold T1, and the difference K1 between the environment temperature and the saturation temperature corresponding to the outlet pressure of the external heat exchanger is less than a threshold T2, or the difference K2 between the target air outlet temperature of the air conditioning box and the actual air outlet temperature is less than a threshold T3, the controller controls the air conditioning system to run in a heat pump mode: controls the first valve structure to act to arrange the first evaporation flow path in parallel with the second evaporation flow path, and controls the first expansion valve and the second expansion valve to open, so that the external heat exchanger absorbs heat from the environment; Step 200, when the difference K1 between the ambient temperature and the saturation temperature corresponding to the outlet pressure of the external heat exchanger is greater than or equal to a threshold T2, or the difference K2 between the target air outlet temperature of the air conditioning box and the actual air outlet temperature is greater than or equal to a threshold T3, the controller controls the air conditioning system to run a defrosting mode: controls the first valve structure to act to connect the two interfaces of the external heat exchanger to the first heat exchanger outlet and the second expansion valve inlet respectively, controls the first expansion valve to close and the second expansion valve to open, so that the external heat exchanger dissipates heat to the environment; Step 300, after the defrosting mode runs for a time t, return to step 100.

9. The dual-heat-source air-source thermal management control method of claim 8, wherein, The threshold T1 is set to one of -15~0℃, the threshold T2 is set to one of 8~12℃, the threshold T3 is set to one of 8~15℃, and the running time t is set to 1~5min.

10. The dual-heat-source air-source thermal management control method of claim 8, wherein, The heat management control method further comprises a first valve structure control method, when the first valve structure comprises a first control valve S1, a second control valve S2, a third control valve S3 and a fourth control valve S4, the control method of the first valve structure comprises: When the controller controls the air conditioning system to run a heat pump mode, the first control valve S1, the second control valve S2, the first expansion valve and the second expansion valve are controlled to open, and the third control valve S3 and the fourth control valve S4 are controlled to close; When the controller controls the air conditioning system to run a defrosting mode, the third control valve S3, the fourth control valve S4 and the second expansion valve are controlled to open, and the first control valve S1, the second control valve S2 and the first expansion valve are controlled to close.

11. The dual-heat-source air-source thermal management control method of claim 10, wherein, When the air conditioning system comprises a third evaporation flow path, the third expansion valve is set to a thermal expansion valve, and the first valve structure further comprises a fifth control valve S5, the heat management control method further comprises: when the passenger compartment issues a refrigeration request, the controller controls the air conditioning system to run a refrigeration mode, controls the third control valve S3, the fourth control valve S4, the fifth control valve S5 and the second expansion valve to open, and controls the first control valve S1, the second control valve S2 and the first expansion valve to close; When the air conditioning system comprises a third evaporation flow path, the third expansion valve is set to an electronic expansion valve, the heat management control method further comprises: when the passenger compartment issues a refrigeration request, the controller controls the air conditioning system to run a refrigeration mode, controls the third control valve S3, the fourth control valve S4, the second expansion valve and the third expansion valve to open, and controls the first control valve S1, the second control valve S2 and the first expansion valve to close.

Images