Low-temperature control method and system for heat pump system, storage medium and vehicle

Abstract

The application provides a low-temperature control method and system of a heat pump system, a storage medium and a vehicle. The method comprises: obtaining the electric drive outlet water temperature of an electric drive circuit after the vehicle is powered on; controlling the start of electric drive active heating when the electric drive outlet water temperature is lower than a first predetermined temperature threshold; obtaining the suction port pressure of the compressor when receiving a passenger cabin heating request; and controlling the compressor to enter a pulse start mode when the suction port pressure is lower than a predetermined pressure threshold, wherein the pulse start mode is a mode in which the compressor is started by running at a predetermined low speed for a first time length and then stopping for a second time length. The application does not need to additionally increase a PTC heater, and can start and continuously and stably operate an R134a heat pump system in an environment temperature of-30 DEG C and above.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicles, in particular to a low-temperature control method and system of a heat pump system, a storage medium and a vehicle. BACKGROUND

[0002] With the development of new energy and the improvement of environmental awareness, the market share of electric vehicles is gradually increasing. In order to improve the energy utilization rate of electric vehicles and reduce the energy consumption of the whole vehicle, more and more electric vehicles are equipped with heat pump systems, but most of the R134a heat pump systems cannot start and continuously run stably at an environmental temperature of-20℃ and below, and the purpose of reducing energy consumption has not been achieved.

[0003] The current technology is to add a PTC heater (high-pressure liquid or air heater) upstream of the chiller in the cooling liquid circuit, heat the cooling liquid through the PTC heater to increase the temperature of the refrigerant in the cooling liquid circuit, so that the compressor can start in a low-temperature environment. However, if only the PTC heater is used to heat the refrigerant to meet the low-pressure requirement, it needs to wait for more than 30 minutes, which cannot meet the customer's heating demand, and starting the compressor at an environmental temperature below-20℃ / low pressure below 1 bar can easily cause damage to the compressor. SUMMARY

[0004] The purpose of the embodiments of the present application is to provide a low-temperature control method and system of a heat pump system, a storage medium and a vehicle, which can start and continuously run stably at an environmental temperature of-30℃ and above without additional PTC heater.

[0005] One aspect of the embodiments of the present application provides a low-temperature control method of a heat pump system. The method comprises: obtaining the electric drive outlet water temperature of the electric drive circuit after the whole vehicle is powered on; controlling to start the electric drive active heating when the electric drive outlet water temperature is lower than a first predetermined temperature threshold; obtaining the suction port pressure of the compressor when receiving a passenger compartment heating request; controlling to enter the pulse start mode of the compressor when the suction port pressure is lower than a predetermined pressure threshold, the pulse start mode of the compressor being to start the compressor in a manner that the compressor runs at a predetermined low speed for a first time length, and then stops for a second time length.

[0006] Further, the heat pump system comprises a first throttling valve, a second throttling valve, a third throttling valve, a first heat exchanger, a second heat exchanger and a third heat exchanger, one end of the first throttling valve is connected with the exhaust port of the compressor through the first heat exchanger, the other end of the first throttling valve is connected with the suction port of the compressor through the second heat exchanger, the two ends of the second throttling valve are connected with the suction port and the exhaust port of the compressor respectively, one end of the third throttling valve is connected with the second heat exchanger, the other end of the third throttling valve is connected with the suction port of the compressor through the third heat exchanger, and the method further comprises: in the compressor pulse starting mode, controlling the first throttling valve to start and the second throttling valve and the third throttling valve to close.

[0007] Further, the method further comprises: in the compressor pulse starting mode, controlling the compressor to run at a predetermined low speed for a first predetermined time length, and then stopping to wait for a second predetermined time length, and repeating the above process a predetermined number of times at most.

[0008] Further, the method further comprises: when the suction port pressure of the compressor is still lower than the predetermined pressure threshold after the compressor pulse starting reaches the predetermined number of times, then maintaining the state that the suction port pressure is lower than the predetermined pressure threshold for more than a third predetermined time length, and then controlling to enter the compressor pulse starting mode.

[0009] Further, the method further comprises: during the operation of the compressor pulse starting mode, continuously acquiring the suction port pressure of the compressor; when the suction port pressure is not lower than the predetermined pressure threshold, then controlling to enter the judgment of the heat pump condition; when the heat pump condition is met, then controlling to enter the heat pump mode.

[0010] Further, when the heat pump condition is met, then controlling to enter the heat pump mode, comprising: when the suction port pressure is in the interval of 0.9bar-1.1bar and the operation is less than a fourth predetermined time length, or the suction port pressure is not lower than 1.1bar, then determining that the heat pump condition is met, and controlling to enter the heat pump mode, the method further comprises: when the suction port pressure is in the interval of 0.9bar-1.1bar and the operation is more than a fifth predetermined time length, then controlling the compressor to stop.

[0011] Further, the method further comprises: when the outlet water temperature of the electric drive is higher than a second predetermined temperature threshold, then controlling to close the electric drive active heating; when the outlet water temperature of the electric drive is not lower than a third predetermined temperature threshold, then controlling to enter the judgment of the heat pump condition.

[0012] Further, the method further comprises: when the outlet water temperature of the electric drive is not lower than a third predetermined temperature threshold, then controlling to enter the judgment of the heat pump condition.

[0013] Another aspect of the embodiments of the present application provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the steps of the low-temperature control method of the heat pump system.

[0014] Still another aspect of the embodiments of the present application provides a low-temperature control system of a heat pump system. The highest vehicle speed control system comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the low-temperature control method of the heat pump system when executing the computer program.

[0015] Still another aspect of the embodiments of the present application provides a vehicle. The vehicle comprises a heat pump system and a low-temperature control system of the heat pump system, the heat pump system comprises a refrigerant circuit and an electric drive circuit, the refrigerant circuit comprises a first refrigerant circuit and a second refrigerant circuit, the first refrigerant circuit comprises a compressor, a first heat exchanger, a first throttling valve, a second heat exchanger, and a second throttling valve, an exhaust port of the compressor is connected with a first end of the first heat exchanger, a second end of the first heat exchanger is connected with one end of the first throttling valve, the other end of the first throttling valve is connected with a suction port of the compressor through the second heat exchanger, and two ends of the second throttling valve are respectively connected with the suction port and the exhaust port of the compressor, the second refrigerant circuit comprises a third throttling valve and a third heat exchanger, one end of the third throttling valve is connected with a second end of the second heat exchanger, and the other end of the third throttling valve is connected with the suction port of the compressor through the third heat exchanger, and the low-temperature control system is used for controlling the heat pump system.

[0016] The low-temperature control method of the heat pump system of one or more embodiments of the present application can quickly raise the temperature of the refrigerant in the heat pump system, so that the low pressure is quickly raised to the pressure requirement for continuous operation, so that the normal heat pump mode can be entered faster to meet the customer's heating demand.

[0017] The low-temperature control method of the heat pump system of one or more embodiments of the present application can widen the working temperature of the heat pump to -30°C through the electric drive active heating and the compressor pulse start mode. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 The structure diagram of the heat pump system of one embodiment of the present application.

[0019] Figure 2 The flowchart of the low-temperature control method of the heat pump system of one embodiment of the present application.

[0020] Figure 3 The specific flowchart of the low-temperature control method of the heat pump system of the present application.

[0021] Figure 4 This is a structural diagram of a heat pump system in an embodiment of the present application in an electric drive active heating and compressor pulse start mode.

[0022] Figure 5 This is a schematic structural diagram of a heat pump system in heat pump mode according to an embodiment of the present application.

[0023] Figure 6 This is a schematic block diagram of a low-temperature control system of a heat pump system according to one embodiment of the present application. DETAILED DESCRIPTION

[0024] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of devices consistent with certain aspects of the present application, as detailed in the appended claims.

[0025] The low temperature control method, system, storage medium and vehicle of the heat pump system of the present application are described in detail below with reference to the accompanying drawings. In the absence of conflict, the features of the following embodiments and implementations can be combined with each other.

[0026] Figure 1 The schematic diagram of the heat pump system 100 according to one embodiment of the present application is disclosed. Figure 1 As shown, heat pump system 100 includes a refrigerant circuit 110, a passenger compartment circuit 140, a battery circuit 150, and an electric drive circuit 160. Passenger compartment circuit 140 includes a heater water pump (HCWP). Battery circuit 150 includes a battery 151 and a battery water pump (BCPF). Electric drive circuit 160 includes an electric drive 161 and an electric water pump (EDCP).

[0027] The refrigerant circuit 110 includes a first refrigerant circuit 120 and a second refrigerant circuit 130. The first refrigerant circuit 120 includes a compressor 111, a first heat exchanger 112, a first throttle valve BEXV, a second heat exchanger 113, and a second throttle valve AEXV. The exhaust port of the compressor 111 is connected to the first end of the first heat exchanger 112. The second end of the first heat exchanger 112 is connected to one end of the first throttle valve BEXV. The other end of the first throttle valve BEXV is connected to the intake port of the compressor 111 via the second heat exchanger 113. The two ends of the second throttle valve AEXV are respectively connected to the intake and exhaust ports of the compressor 111. The second refrigerant circuit 130 includes a third throttle valve EEXV and a third heat exchanger 114. One end of the third throttle valve EEXV is connected to the second end of the second heat exchanger 113, and the other end of the third throttle valve EEXV is connected to the intake port of the compressor 111 via the third heat exchanger 114. The first heat exchanger 112 may be a water-cooled condenser, and the third heat exchanger 114 may be an evaporator. The first throttle valve BEXV, the second throttle valve AEXV, and the third throttle valve EEXV may be electronic expansion valves.

[0028] Heat pump system 100 also includes a coolant circuit 180, a nine-way valve 170, and a three-way valve HCTV. Coolant circuit 180 includes a second heat exchanger 113. The two ends of coolant circuit 180 are connected to two different ports of the nine-way valve 170. The passenger compartment circuit 140 can be connected to the coolant circuit 180 via the nine-way valve 170 and the three-way valve HCTV. Both ends of the battery circuit 150 and the electric drive circuit 160 are connected to two different ports of the nine-way valve 170.

[0029] The present application provides a low-temperature control method for the heat pump system 100 . Figure 2 A flow chart of a low temperature control method for a heat pump system according to an embodiment of the present application is disclosed. Figure 2 As shown, a low-temperature control method for a heat pump system according to an embodiment of the present application may include steps S201 to S205.

[0030] In step S201 , the vehicle is powered on.

[0031] In step S202 , after the vehicle is powered on, the electric drive outlet water temperature Tout of the electric drive circuit is obtained.

[0032] In step S203 , when the water temperature Tout at the electric drive outlet is lower than a first predetermined temperature threshold, the electric drive active heating is started.

[0033] In step S204 , when a passenger compartment heating request is received, the intake port pressure Pin of the compressor 111 is acquired.

[0034] In step S205, when the suction port pressure Pin is lower than a predetermined pressure threshold, the compressor pulse start mode is controlled to start, in which the compressor 111 is operated at a predetermined low speed for a first time duration, and then stopped for a second time duration.

[0035] The low-temperature control method of the heat pump system of the present application can quickly raise the temperature of the refrigerant in the heat pump system, so that the low pressure is quickly raised to the pressure requirement for continuous operation, thereby entering the normal heat pump mode faster to meet the customer's heating demand.

[0036] The low-temperature control method of the heat pump system of the present application can widen the working temperature of the heat pump to -30℃ through electric drive active heating and compressor pulse start mode.

[0037] In some embodiments, the low-temperature control method of the heat pump system of the present application can further include step S206.

[0038] In step S206, in the compressor pulse start mode, the first throttling valve BEXV is controlled to be started, and the second throttling valve AEXV and the third throttling valve EEXV are controlled to be closed.

[0039] Optionally, in order to reduce the impact and pressure fluctuation during start-up, the first throttling valve BEXV can be controlled to be soft-started, so that the fluid flow is gradually increased by gradually adjusting the opening degree of the first throttling valve BEXV.

[0040] The low-temperature control method of the heat pump system of the present application will be described in detail below Figure 3 with reference to a specific flowchart.

[0041] Figure 3 A specific flowchart of the low-temperature control method of the heat pump system of the present application is disclosed. As shown in Figure 3 step S301, the vehicle is powered on. In step S302, after the vehicle is powered on, the electric drive outlet water temperature Tout is determined. In step S303, when the electric drive outlet water temperature Tout is lower than a first predetermined temperature threshold, for example: Tout≤-15℃, the electric drive active heating is controlled to be started. In step S304, when the electric drive outlet water temperature Tout is higher than a second predetermined temperature threshold, for example: Tout≥0℃, the electric drive active heating is controlled to be closed. At the same time, in step S305, when the electric drive outlet water temperature Tout is not lower than a third predetermined temperature threshold, for example: Tout≥-18℃, the heat pump condition determination is controlled to be entered.

[0042] In step S306, the passenger compartment has a heating request. When the passenger compartment has a heating request, the process proceeds to step S307. In step S307, a compressor low pressure determination is made, i.e. the suction port pressure Pin of the compressor 111 is determined. At an ambient temperature of -30°C, the start-up low pressure of the suction port of the compressor 111 is about 0.85 bar. When the suction port pressure Pin of the compressor 111 is lower than a predetermined pressure threshold, for example: 0.85 bar < Pin < 0.9 bar, the process proceeds to step S308. In step S308, it is determined whether it is a first start-up. If it is a first start-up, the process directly proceeds to step S309. In step S309, a compressor pulse start-up mode is entered, i.e. the compressor 111 is controlled to operate at a predetermined low speed for a first time duration, and then stopped for a second time duration, for example: the compressor 111 is controlled to operate at 850 rpm (revolutions per minute) for 5 s (seconds), and then stopped, and after waiting for 5 s, the compressor 111 is started again.

[0043] In order to better protect the compressor 111, the number of times of pulse start-up of the compressor 111 can be limited. In some embodiments, the low temperature control method of the heat pump system of the present application can further comprise: in the compressor pulse start-up mode, the compressor 111 is controlled to operate at a predetermined low speed for a first predetermined time duration, and then stopped for a second predetermined time duration, and the above process is repeated a maximum of a predetermined number of times N, for example N = 5.

[0044] In some embodiments, the low temperature control method of the heat pump system of the present application can further comprise: when the suction port pressure Pin of the compressor 111 is still lower than the predetermined pressure threshold after the compressor 111 is pulse started for the predetermined number of times N, the process can only proceed to the compressor pulse start-up mode in step S309 after the suction port pressure Pin is lower than the predetermined pressure threshold for more than a third predetermined time duration. Therefore, in step S308, if it is not a first start-up, it is further determined whether the low pressure is too low for more than a third predetermined time duration, and the third predetermined time duration can be, for example, 1 h (hour). That is, after the compressor 111 is pulse started for, for example, 5 times, when the suction port pressure Pin of the compressor 111 is still too low (lower than the predetermined pressure threshold, for example < 0.9 bar), the process can only proceed to the compressor pulse start-up mode in step S309 after the low pressure is too low for more than 1 h. Thus, the compressor 111 can be prevented from being damaged by too frequent start-up.

[0045] When the result of the determination in step S308 is that the first start-up or the low pressure is too low for more than 1 h is not satisfied, the process proceeds to step S311. In step S311, the compressor 111 is controlled to stop.

[0046] Figure 4A structure schematic diagram of the heat pump system in the electric drive active heating and compressor pulse start mode is disclosed in one embodiment of the present application. In combination with reference to Figure 4 As shown, when the electric drive outlet water temperature Tout is too low, the electric drive active heating can be used to improve the electric drive outlet water temperature Tout. In the compressor pulse start mode, the first throttling valve BEXV is controlled to soft start, the second throttling valve AEXV and the third throttling valve EEXV are controlled to close, and the compressor 111 is controlled to start at a low speed.

[0047] In some embodiments, the low temperature control method of the heat pump system of the present application can further include: continuously acquiring the suction port pressure Pin of the compressor 111 during the operation of the compressor pulse start mode; when the suction port pressure Pin is not lower than a predetermined pressure threshold, the heat pump condition is determined; when the heat pump condition is met, the heat pump mode is entered.

[0048] Referring back to Figure 3 As shown, in step S307, the low pressure of the compressor 111 is continuously judged during the operation of the compressor pulse start mode. When the suction port pressure Pin of the compressor 111 is not lower than a predetermined pressure threshold, for example: Pin≥0.9bar, it can enter step S305 to determine the heat pump condition. When the suction port pressure Pin of the compressor 111 is in the interval of 0.9bar-1.1bar, i.e. 0.9bar≤Pin<1.1bar, and the operation is less than a fourth predetermined time length, or the suction port pressure Pin is not lower than 1.1bar, i.e. Pin≥1.1bar, it is determined that the heat pump condition is met, and the process enters step S310. In step S310, the heat pump mode is entered.

[0049] Figure 5 A structure schematic diagram of the heat pump system in the heat pump mode is disclosed in one embodiment of the present application. As shown in Figure 5 As shown, in the heat pump mode, the first throttling valve BEXV and the second throttling valve AEXV are controlled to soft start, the compressor 111 is controlled to soft start, and the opening or closing of the third throttling valve EEXV is controlled based on the evaporator anti-liquid accumulation logic.

[0050] Regarding refrigerant circuit 110: After compressor 111 performs work, the low-temperature, low-pressure gaseous refrigerant becomes high-pressure, high-temperature gaseous refrigerant. After dissipating heat through first heat exchanger 112 (the condenser), it transfers this heat to passenger compartment circuit 140, becoming high-pressure, high-temperature liquid refrigerant. After throttling through first throttle valve BEXV, it becomes low-temperature, low-pressure refrigerant. It then passes through second heat exchanger 113 (the cooler), absorbing heat from battery circuit 150 and becoming low-temperature, low-pressure gaseous refrigerant. It then enters compressor 111 for the next cycle. Regarding passenger compartment circuit 140: High-temperature hot water flowing through first heat exchanger 112 (the condenser) passes through three-way valve HCTV and then exchanges heat through air conditioner heat exchanger Hex, transferring heat to the passenger compartment. The released low-temperature water then passes through heater water pump HCWP before passing through first heat exchanger 112 (the condenser) again for the next cycle. For the electric drive circuit 160: Low-temperature cold water flows through the second heat exchanger 113, which serves as a cooler, passes through the nine-way valve 170, then absorbs heat through the electric drive, passes through the nine-way valve 170 again, and finally flows back to the second heat exchanger 113, which serves as a cooler, to release heat. This transfers the waste heat from the electric drive to the refrigerant circuit 110, which then transfers it to the passenger compartment circuit 140, thereby providing supplemental heat to the passenger compartment.

[0051] In some embodiments, the low-temperature control method of the heat pump system of the present application may further include: when the suction port pressure Pin is in the range of 0.9 bar-1.1 bar, that is, 0.9 bar≤Pin<1.1 bar and the operation exceeds the fifth predetermined time, then entering step S311, controlling the compressor 111 to stop.

[0052] When the compressor 111 is stopped, if there is a heating request for the passenger compartment, the above logic judgment is repeated.

[0053] The low-temperature control method of the heat pump system of the present application cleverly utilizes the characteristic of the compressor 111 that can operate briefly at extremely low pressure through electric active heating and compressor pulse start-up mode, so that the refrigerant flows intermittently, bringing the heat in the second heat exchanger serving as a cooler more fully into the heat pump system.

[0054] The low-temperature control method of the heat pump system of the present application uses electric drive active heating and compressor pulse start mode, without the need for additional PTC heaters. The electric drive active heating is started to increase the refrigerant temperature on the second heat exchanger side, and the heat pump system temperature is increased through the compressor pulse start mode. During the pulse start mode, as long as the low pressure reaches the low pressure requirement for continuous operation, the normal heat pump mode is immediately entered, so that the R134a heat pump system can be started and continuously and stably operated at an ambient temperature of -30°C or above.

[0055] The present application also provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the low-temperature control method for a heat pump system are implemented.

[0056] The present application also provides a low-temperature control system 600 of a heat pump system. Figure 6 A schematic block diagram of a low temperature control system 600 of a heat pump system according to an embodiment of the present application is disclosed. Figure 6 As shown, the low-temperature control system 600 of the heat pump system of one embodiment of the present application includes a processor 601, an internal bus 602, a network interface 603, a memory 604 and a non-volatile memory 605, and of course may also include hardware required for other services. The processor 601 can read the corresponding computer program from the non-volatile memory 605 into the memory 604 and then run it to implement the steps of the low-temperature control method of the heat pump system as described above. Of course, in addition to software implementation, this application does not exclude other implementation methods, such as logic devices or a combination of software and hardware, etc., that is, the execution subject of the following processing flow is not limited to each logic unit, but can also be hardware or logic components.

[0057] The low-temperature control system 600 of the heat pump system of the present application can have similar beneficial technical effects as the low-temperature control method of the heat pump system described above, so it will not be described in detail here.

[0058] The present application also provides a vehicle. The vehicle includes a heat pump system 100 and a low-temperature control system 600 of the heat pump system as described above. The low-temperature control system 600 can control the heat pump system 100.

[0059] The above is a detailed introduction to the low-temperature control method, system, storage medium and vehicle of the heat pump system provided in the embodiment of the present application. Specific examples are used herein to illustrate the low-temperature control method, system, storage medium and vehicle of the heat pump system in the embodiment of the present application. The description of the above embodiments is only used to help understand the core idea of ​​the present application and is not intended to limit the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the spirit and principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications should also fall within the scope of protection of the claims attached to the present application.

Claims

1. A low temperature control method for a heat pump system, characterized in that: The method comprises: After the vehicle is powered on, obtain the water temperature at the electric drive outlet of the electric drive circuit; When the water temperature at the electric drive outlet is lower than a first predetermined temperature threshold, controlling to start active heating of the electric drive; When a passenger cabin heating request is received, obtaining the suction port pressure of the compressor; When the pressure at the suction port is lower than a predetermined pressure threshold, the control enters a compressor pulse start mode, in which the compressor is started by running at a predetermined low speed for a first period of time and then stopping to wait for a second period of time.

2. The method according to claim 1, wherein The heat pump system includes a first throttle valve, a second throttle valve, a third throttle valve, a first heat exchanger, a second heat exchanger, and a third heat exchanger, one end of the first throttle valve is connected to the exhaust port of the compressor via the first heat exchanger, the other end of the first throttle valve is connected to the intake port of the compressor via the second heat exchanger, two ends of the second throttle valve are respectively connected to the intake port and the exhaust port of the compressor, one end of the third throttle valve is connected to the second heat exchanger, and the other end of the third throttle valve is connected to the intake port of the compressor via the third heat exchanger, and the method further includes: In the compressor pulse start mode, the first throttle valve is controlled to be started, and the second throttle valve and the third throttle valve are controlled to be closed.

3. The method according to claim 1, wherein Also includes: In the compressor pulse start mode, the compressor is controlled to run at a predetermined low speed for a first predetermined time, and then stopped to wait for a second predetermined time, and the method is repeated at most for a predetermined number of times.

4. The method according to claim 3, wherein Also includes: After the compressor pulse starts for the predetermined number of times, if the suction port pressure of the compressor is still lower than the predetermined pressure threshold, the control is then performed to enter the compressor pulse start mode after the state in which the suction port pressure is lower than the predetermined pressure threshold is maintained for more than a third predetermined time.

5. The method according to claim 1, wherein Also includes: During operation of the compressor in pulse start mode, continuously obtaining the suction port pressure of the compressor; When the air intake pressure is not lower than the predetermined pressure threshold, the control enters the determination of the heat pump condition; When the heat pump conditions are met, the control enters the heat pump mode.

6. The method according to claim 5, wherein When the heat pump condition is met, the control enters the heat pump mode, including: When the air inlet pressure is within the range of 0.9 bar to 1.1 bar and the operation time is less than a fourth predetermined time, or the air inlet pressure is not less than 1.1 bar, it is determined that the heat pump condition is met, and the control enters the heat pump mode; The method further comprises: When the suction port pressure is within the range of 0.9 bar to 1.1 bar and the operation time exceeds a fifth predetermined time, the compressor is controlled to stop.

7. The method according to claim 1, wherein Also includes: When the water temperature at the electric drive outlet is higher than a second predetermined temperature threshold, the electric drive active heating is controlled to be turned off; When the water temperature at the electric drive outlet is not lower than a third predetermined temperature threshold, the control enters the determination of the heat pump condition.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the low-temperature control method of the heat pump system according to any one of claims 1 to 7 are implemented.

9. A low temperature control system for a heat pump system, characterized in that: The method comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the low-temperature control method for the heat pump system as described in any one of claims 1 to 7 are implemented.

10. A vehicle, characterized in that: The heat pump system includes a heat pump system and a low-temperature control system as claimed in claim 9, wherein the heat pump system includes a refrigerant circuit and an electric drive circuit, the refrigerant circuit includes a first refrigerant circuit and a second refrigerant circuit, the first refrigerant circuit includes a compressor, a first heat exchanger, a first throttle valve, a second heat exchanger and a second throttle valve, the exhaust port of the compressor is connected to the first end of the first heat exchanger, the second end of the first heat exchanger is connected to one end of the first throttle valve, the other end of the first throttle valve is connected to the intake port of the compressor through the second heat exchanger, the two ends of the second throttle valve are respectively connected to the intake port and exhaust port of the compressor, the second refrigerant circuit includes a third throttle valve and a third heat exchanger, one end of the third throttle valve is connected to the second end of the second heat exchanger, and the other end of the third throttle valve is connected to the intake port of the compressor through the third heat exchanger, and the low-temperature control system is used to control the heat pump system.

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