Whole-vehicle thermal management system of electric vehicle and control method of whole-vehicle thermal management system

Abstract

The invention discloses an electric vehicle thermal management system which comprises a refrigerant management module, a passenger compartment thermal management module, a battery pack thermal management module, an electric drive thermal management module and a low-temperature radiator module, wherein the passenger compartment thermal management module, the battery pack thermal management module, the electric drive thermal management module and the low-temperature radiator module are communicated with a twelve-way valve. The refrigerant management module is provided with a hot gas bypass branch, the hot gas bypass branch is provided with an electromagnetic valve with the opening degree capable of being controlled, and connection or disconnection between the refrigerant module and the passenger compartment heat management module, the battery pack heat management module, the electric drive heat management module and the low-temperature radiator module and the working mode of the refrigerant management module are completed by combining a twelve-way valve. High integration of an electric automobile heat management system can be achieved, normal work of a heat pump under the extremely low temperature working condition is guaranteed, the heating capacity is improved, and the problem that a compressor is frequently started and stopped during refrigeration is solved. The invention further provides a control method of the electric vehicle thermal management system.

Description

Technical Field

[0001] The invention relates to a whole vehicle thermal management system for an electric vehicle and a control method thereof, belonging to the technical field of whole vehicle thermal management for electric vehicles. Background Art

[0002] Direct and semi-indirect heat pump technologies have been developed and improved for many years in the automotive field, and the performance and reliability of the system have been significantly improved. However, the refrigerant filling amount required by direct and semi-indirect heat pump technology systems is generally high, which is contrary to the strict requirements of current regulations on the filling amount of new refrigerants. Full indirect heat pump technology solves this problem.

[0003] Under normal temperature refrigeration conditions, when the compressor runs at the lowest speed, the refrigeration of the thermal management system may still be higher than the system refrigeration load. Frequent startup of the compressor will cause irreversible damage to the compressor. Under extreme winter conditions, due to the low temperature of the refrigerant, the compressor has problems such as difficulty in starting and insufficient heating capacity, and the use of PTC greatly increases the cost of the thermal management system. The introduction of hot gas bypass technology can enhance the heating capacity of the heat pump system in low temperature environments and stabilize the system pressure by adjusting the bypass branch flow, solving problems such as pressure fluctuations that may occur during the operation of the heat pump system.

[0004] The thermal management system of electric vehicles nowadays generally pursues integration, but the integration level is not high. The needs of electric vehicles for various working modes are realized through complex cross-pipes, which increases the resistance loss caused by unnecessary components or pipes in some working modes. In addition, the existing system still has the problem of effective utilization of some energy, which affects the improvement of electric vehicle endurance. Summary of the invention

[0005] The present invention designs and develops a thermal management system for an electric vehicle. In the refrigerant management module, a compressor and a solenoid valve form a bypass branch, which can be combined with other modules to form different thermal management circuits. It has a high degree of integration, expands the combination of different working modes of various thermal management modules of electric vehicles, and saves space.

[0006] The present invention also designs and develops a control method for the normal thermal management system of an electric vehicle. By controlling the opening of the solenoid valve and adjusting the opening and closing of the twelve-way valve, different thermal management circuits are formed to ensure the normal operation of the heat pump under low-temperature conditions, improve the heating capacity, solve the problem of frequent start and stop of the compressor during refrigeration, and improve energy utilization.

[0007] The technical solution provided by the present invention is:

[0008] A thermal management system for an electric vehicle, comprising:

[0009] A refrigerant management module and a passenger compartment thermal management module, a battery pack thermal management module, an electric drive thermal management module and a low-temperature radiator module respectively connected to the twelve-way valve;

[0010] The refrigerant management module includes:

[0011] compressor;

[0012] WCON, which includes a refrigerant side and a coolant side, the outlet of the compressor is connected to the inlet of the refrigerant side of the WCON;

[0013] A liquid storage tank, wherein the outlet of the WCON refrigerant side is connected to the inlet of the liquid storage tank;

[0014] An electronic expansion valve, one end of which is connected to the outlet of the liquid storage tank;

[0015] A chiller, comprising a refrigerant side and a coolant side, wherein the inlet of the chiller refrigerant side is connected to the other end of the electronic expansion valve, and the outlet of the chiller refrigerant side is connected to the inlet of the compressor;

[0016] A solenoid valve, one end of which is connected to the outlet of the compressor, and the other end of which is connected to the inlet of the compressor, and a hot gas bypass branch is formed between the solenoid valve and the compressor;

[0017] The passenger compartment thermal management module includes:

[0018] Port No. 3 of the twelve-way valve, which is connected to the inlet of the coolant side of the WCON;

[0019] a fourth water pump, the inlet of which is connected to the outlet of the coolant side of the WCON;

[0020] A heater core, wherein the outlet of the fourth water pump is connected to the inlet of the heater core;

[0021] Port No. 1 of the twelve-way valve is connected to the outlet of the heater core;

[0022] Port No. 6 of the twelve-way valve is connected to the coolant side inlet of the chiller;

[0023] A third water pump, the inlet of which is connected to the outlet of the chiller coolant side;

[0024] a cold air core, the inlet of which is connected to the outlet of the third water pump;

[0025] Port No. 8 of the twelve-way valve is connected to the outlet of the cold air core;

[0026] The battery pack thermal management module includes:

[0027] Port No. 11 and Port No. 12 of the twelve-way valve;

[0028] Port No. 1 of the first proportional three-way valve is connected to port No. 11 of the twelve-way valve;

[0029] Port No. 2 of the first proportional three-way valve;

[0030] Port No. 3 of the first proportional three-way valve is connected to port No. 12 of the twelve-way valve;

[0031] a first water pump, the inlet of which is connected to port No. 2 of the first proportional three-way valve;

[0032] a battery pack, wherein a coolant inlet thereof is connected to an outlet of the first water pump;

[0033] Port No. 1 of the second proportional three-way valve, which is connected to the outlet of the battery pack coolant;

[0034] Port No. 3 of the second proportional three-way valve is connected to the inlet of the first water pump;

[0035] Port No. 2 of the second proportional three-way valve is connected to port No. 12 of the twelve-way valve;

[0036] The electric drive thermal management module includes:

[0037] Ports 9 and 10 of the twelve-way valve;

[0038] a second water pump, the inlet of which is connected to port No. 9 of the twelve-way valve;

[0039] An electric drive system, whose coolant inlet is connected to the outlet of the second water pump, and the coolant outlet of the electric drive system is connected to port No. 10 of the twelve-way valve;

[0040] The low temperature heat sink module includes:

[0041] Port No. 4 of the twelve-way valve, Port No. 5 of the twelve-way valve;

[0042] a low-temperature radiator, the inlet of which is connected to the No. 4 port of the twelve-way valve, and the outlet of which is connected to the No. 5 port of the twelve-way valve;

[0043] Among them, the bypass branch is opened or closed by controlling the opening of the solenoid valve, and the bypass branch is combined with the twelve-way valve by adjusting the opening and closing of each port of the twelve-way valve, so as to complete the connection or disconnection between the refrigerant module and the passenger compartment thermal management module, the battery pack thermal management module, the electric drive thermal management module and the low-temperature radiator module, thereby forming different thermal management modes.

[0044] Preferably, it also includes:

[0045] A first temperature and pressure sensor is provided on a pipeline connecting the outlet of the compressor and the solenoid valve and the refrigerant side of the WCON;

[0046] The second temperature and pressure sensor is arranged on a pipeline connecting the inlet of the compressor and the solenoid valve and the chiller refrigerant side.

[0047] Preferably, it also includes:

[0048] a first kettle, one end of which is connected to the cooling liquid side inlet of the chiller, and the other end of which is connected to the cooling liquid side outlet of the chiller;

[0049] The second kettle has one end connected to the coolant side inlet of the WCON and the other end connected to the coolant side outlet of the WCON.

[0050] Preferably, it also includes:

[0051] A first temperature sensor, which is arranged on a pipeline connecting the battery pack and the first water pump;

[0052] A second temperature sensor is disposed on a pipeline connecting the battery pack and port No. 1 of the second proportional three-way valve;

[0053] A control method for a thermal management system of an electric vehicle, using the thermal management system of the electric vehicle, comprising:

[0054] The refrigerant management module includes first to fourth working modes, and the refrigerant temperature and pressure are fed back by the first temperature and pressure sensor and the second temperature and pressure sensor to realize the switching and adjustment of different modes of the refrigerant management module;

[0055] When the refrigerant pressure at the compressor outlet is higher than the minimum pressure allowed for the solenoid valve to open, and the ambient temperature is lower than the minimum operating temperature of the refrigerant management module, the first working mode of the refrigerant module is started:

[0056] Among them, the minimum pressure allowed for the solenoid valve to open is 0.2MPa, and the minimum operating temperature of the refrigerant management module is -15℃;

[0057] The electronic expansion valve is closed, the compressor is started at a low speed, and the hot gas bypass branch solenoid valve is opened, so that the high-temperature and high-pressure refrigerant at the compressor outlet enters the hot gas bypass branch and enters the compressor inlet after passing through the solenoid valve on the hot gas bypass branch;

[0058] When the refrigerant pressure at the compressor outlet is higher than the minimum pressure allowed for the solenoid valve to open, and the refrigerant superheat at the compressor inlet is less than the set superheat for the compressor to operate reliably, the second working mode of the refrigerant module is started:

[0059] Among them, the refrigerant superheat is 10-20℃;

[0060] Start the compressor at a low speed, open the electronic expansion valve, adjust the opening of the hot gas bypass branch solenoid valve, control the refrigerant flow entering the hot gas bypass branch, part of the high-temperature and high-pressure refrigerant enters the hot gas bypass branch through the compressor outlet, enters the compressor inlet after passing through the solenoid valve on the hot gas bypass branch, and enters the compressor after mixing with the low-temperature and low-pressure refrigerant at the compressor inlet; the remaining high-temperature and high-pressure refrigerant enters the refrigerant side inlet of the WCON through the compressor outlet, flows out from the refrigerant side outlet of the WCON, enters the liquid storage tank inlet, enters one end of the electronic expansion valve through the liquid storage tank outlet, flows out through the other end of the electronic expansion valve into the Chiller refrigerant side inlet, and enters the compressor inlet through the Chiller refrigerant side outlet;

[0061] The refrigerant temperature and pressure are fed back through the first temperature and pressure sensor and the second temperature and pressure sensor to realize the distribution of the refrigerant flow entering the hot gas bypass and the refrigerant side inlet flow entering WCON2. When the outlet temperature and pressure are higher than the allowable exhaust temperature of the compressor, the solenoid valve is opened until the exhaust temperature drops to the allowable exhaust temperature, and the opening of the solenoid valve is fixed;

[0062] When the refrigerant pressure at the compressor outlet is higher than the maximum pressure allowed by the solenoid valve, and the superheat of the refrigerant at the compressor inlet is not less than the designed superheat for the reliable operation of the compressor, the third working mode of the refrigerant management module is started;

[0063] Among them, the maximum pressure allowed for the solenoid valve to open is 0.5MPa;

[0064] The solenoid valve on the hot gas bypass branch is closed, the electronic expansion valve is opened, and the high-temperature and high-pressure refrigerant enters the WCON refrigerant side inlet through the compressor outlet, flows out from the WCON refrigerant side outlet, enters the liquid storage tank inlet, enters one end of the electronic expansion valve through the liquid storage tank outlet, flows out through the other end of the electronic expansion valve into the Chiller refrigerant side inlet, and enters the compressor inlet through the Chiller refrigerant side outlet;

[0065] When the refrigerant module management system mode is the fourth refrigerant working mode:

[0066] The solenoid valve on the hot gas bypass branch is closed, the electronic expansion valve is closed, and the refrigerant management module does not work.

[0067] Beneficial effects of the present invention:

[0068] The electric vehicle thermal management system provided by the present invention forms a hot gas bypass branch between the solenoid valve and the compressor. The hot gas bypass branch directly bypasses part of the high-temperature and high-pressure gaseous refrigerant to the suction side of the compressor, thereby increasing the suction temperature and pressure of the compressor, thereby increasing the circulation flow of the refrigerant in the system, thereby increasing the heating capacity of the heat pump system in a low-temperature environment, and at the same time can realize the adjustment of the refrigerant flow under normal temperature refrigeration conditions, thereby achieving the purpose of stable operation of the compressor.

[0069] The fully indirect heat pump technology provided by the present invention reduces the amount of refrigerant required for the system. The addition of hot gas bypass technology meets the smooth operation of the compressor under normal temperature refrigeration conditions and the heating needs under extreme winter conditions, broadening the application scenarios of the heat pump.

[0070] The present invention uses innovative technical means to skillfully integrate the numerous complex valves of the traditional electric vehicle thermal management system into a highly integrated process to form a twelve-way valve. Not only does it greatly reduce the number of system pipelines, but it also makes the system structure compact. At the same time, the twelve-way valve can realize individual and coordinated control of each thermal management module, which can strongly improve the energy efficiency of the thermal management system, ensure that the system can operate stably under various working conditions, further enhance the endurance of the vehicle, and provide users with more lasting travel guarantees. At the same time, this series of improvements is also conducive to achieving lightweighting of the vehicle, reducing energy consumption, and improving the overall performance and handling of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 This is a schematic diagram of the structure of the thermal management system for an electric vehicle according to the present invention;

[0072] Figure 2 It is a schematic diagram of a system cycle in which the refrigerant module management system mode of the electric vehicle thermal management system of the present invention is the first working mode of the refrigerant module;

[0073] Figure 3 It is a schematic diagram of a system cycle in which the refrigerant module management system mode of the electric vehicle thermal management system of the present invention is the second working mode of the refrigerant module;

[0074] Figure 4 It is a schematic diagram of a system cycle in which the refrigerant module management system mode of the electric vehicle thermal management system of the present invention is the third working mode of the refrigerant module;

[0075] Figure 5 It is a schematic diagram of a system cycle in which the refrigerant module management system mode of the electric vehicle thermal management system of the present invention is the fourth working mode of the refrigerant module;

[0076] Figure 6It is a schematic diagram of the system cycle of the vehicle thermal management system of the present invention in the third working mode of passenger compartment heating, battery pack heating, electric drive waste heat utilization / reduced efficiency heating, air source heat pump heating mode, and refrigerant module management system;

[0077] Figure 7 It is a schematic diagram of the system cycle of passenger compartment heating, battery pack waste heat utilization, electric drive waste heat utilization / reduced efficiency heating, air source heat pump heating mode, and refrigerant module management system in the third working mode according to the present invention;

[0078] Figure 8 It is a schematic diagram of the system cycle of the vehicle thermal management system of the present invention in the passenger compartment cooling mode and the refrigerant module management system in the second working mode;

[0079] Fig. 9 It is a schematic diagram of the system cycle of the vehicle thermal management system in the battery pack cooling mode and the refrigerant module management system in the second working mode according to the present invention;

[0080] Fig.10 It is a schematic diagram of the system cycle of the vehicle thermal management system in the battery pack cooling mode and the refrigerant module management system in the third working mode according to the present invention;

[0081] Fig.11 It is a schematic diagram of the system cycle of the vehicle thermal management system in the battery pack cooling mode and the refrigerant module management system in the fourth working mode according to the present invention;

[0082] Fig.12 It is a schematic diagram of the system cycle of the vehicle thermal management system of the present invention in the electric drive heat dissipation mode and the refrigerant module management system in the second working mode;

[0083] Fig.13 It is a schematic diagram of the system cycle of the vehicle thermal management system of the present invention in the electric drive heat dissipation mode and the refrigerant module management system in the third working mode;

[0084] Fig.14 It is a schematic diagram of the system cycle of the vehicle thermal management system of the present invention in the electric drive heat dissipation mode and the fourth working mode of the refrigerant module management system;

[0085] Fig.15 It is a schematic diagram of the system cycle of the vehicle thermal management system of the present invention in the passenger compartment heat storage, battery heat storage, electric drive heat storage mode, and the fourth working mode of the refrigerant module management system;

[0086] Fig.16 It is a schematic diagram of the system cycle of the vehicle thermal management system of the present invention in the passenger compartment defrosting mode and the refrigerant module management system in the second working mode;

[0087] Fig.17 It is a schematic diagram of the system circulation of the refrigerant module in the second working mode of the vehicle thermal management system described in the present invention in the passenger compartment dehumidification mode. DETAILED DESCRIPTION

[0088] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0089] like Figure 1-17 As shown, the present invention provides a thermal management system for an electric vehicle, comprising: a compressor 1, a WCON 2, a liquid storage tank 3, an electronic expansion valve 4, a Chiller 5, a solenoid valve 6, a first temperature and pressure sensor 7, a second temperature and pressure sensor 8, a warm air core 9 in a passenger compartment HVAC assembly, a cold air core 10 in a passenger compartment HVAC assembly, a blower 11 in a passenger compartment HVAC assembly, a first proportional three-way valve 14, a second proportional three-way valve 15, a first water pump 16, a first temperature sensor 17, a battery pack 18, a second temperature sensor 19, a second water pump 20, an electric drive system 21, a low-temperature radiator 23, a third water pump 24, a fourth water pump 25, a first kettle 26, a second kettle 27, and a twelve-way valve 28.

[0090] The vehicle thermal management system includes: refrigerant management module, passenger compartment thermal management module, battery thermal management module, electric drive thermal management module, and low-temperature radiator module.

[0091] The refrigerant management module includes: a compressor 1, a WCON 2, a liquid storage tank 3, an electronic expansion valve 4, a Chiller 5, a solenoid valve 6 and pipelines, wherein the WCON 2 has a refrigerant side and a coolant side, and the Chiller 5 has a refrigerant side and a coolant side; the outlet of the compressor 1 is connected to the inlet of the refrigerant side of the WCON 2, the refrigerant side outlet of the WCON 2 is connected to the inlet of the liquid storage tank 3, the outlet of the liquid storage tank 3 is connected to one end of the electronic expansion valve 4, the other end of the electronic expansion valve 4 is connected to the refrigerant side inlet of the Chiller 5, and the refrigerant side outlet of the Chiller 5 is connected to the compressor inlet;

[0092] The passenger compartment thermal management module includes: the coolant side of WCON 2 connected to the twelve-way valve 28, the fourth water pump 25, the heater core 9 in the passenger compartment HVAC assembly and pipelines, wherein the No. 3 port of the twelve-way valve 28 is connected to the coolant side inlet of WCON 2, the coolant side outlet of WCON 2 is connected to the inlet of the third water pump 24, the outlet of the third water pump 24 is connected to the heater core 28 in the passenger compartment HVAC assembly, and the outlet of the heater core 9 in the passenger compartment HVAC assembly is connected to the No. 1 port of the twelve-way valve 28; it also includes: the coolant side of Chiller 5 connected to the twelve-way valve 28, the third water pump 24, and the coolant core 10 in the passenger compartment HVAC assembly, wherein the No. 6 port of the twelve-way valve 28 is connected to the coolant side inlet of Chiller 5, and the Chiller The coolant side outlet of 5 is connected to the inlet of the third water pump 24, the outlet of the third water pump 24 is connected to the cooling air core 10 in the passenger compartment HVAC assembly, and the outlet of the cooling air core 10 in the passenger compartment HVAC assembly is connected to port 8 of the twelve-way valve 28.

[0093] The battery thermal management module includes: a first proportional three-way valve 14 connected to the twelve-way valve 28, a second proportional three-way valve 15, a first water pump 16, a battery pack 18 and a pipeline, wherein port No. 11 of the twelve-way valve 28 is connected to port No. 1 of the first proportional three-way valve 14, port No. 2 of the first proportional three-way valve 14 is connected to the inlet of the first water pump 16, port No. 3 of the first proportional three-way valve is connected to port No. 12 of the twelve-way valve, the outlet of the first water pump 16 is connected to the coolant inlet of the battery pack 18, the coolant outlet of the battery pack 18 is connected to port No. 1 of the second proportional three-way valve 15, port No. 3 of the second proportional three-way valve 15 is connected to the inlet of the first water pump 16, and port No. 2 of the second proportional three-way valve 15 is connected to port No. 12 of the twelve-way valve 28.

[0094] The electric drive thermal management module includes: a second water pump 20 connected to a twelve-way valve 28, an electric drive system 21, and pipelines. Port No. 9 of the twelve-way valve is connected to the inlet of the second water pump 20, the outlet of the second water pump 20 is connected to the coolant inlet of the electric drive system 21, and the coolant outlet of the electric drive system 21 is connected to port No. 10 of the twelve-way valve 28.

[0095] The low-temperature radiator module includes: a low-temperature radiator 23 and a pipeline connected to a twelve-way valve 28, wherein port No. 4 of the twelve-way valve 28 is connected to the inlet of the low-temperature radiator 23, and the outlet of the low-temperature radiator 23 is connected to port No. 5 of the twelve-way valve 28.

[0096] like Figure 1As shown, the refrigerant module also includes a hot gas bypass branch connected in parallel with the compressor 1 and arranged between the compressor 1 outlet and the compressor 1 inlet. The hot gas bypass branch is provided with an adjustable opening solenoid valve 6. One end of the solenoid valve 2 is connected to the compressor 1 outlet, and the other end of the solenoid valve 2 is connected to the compressor 1 inlet.

[0097] like Figure 1 As shown, a second temperature and pressure sensor 8 is provided on the pipeline connecting the outlet of the compressor 1 with the solenoid valve 6 and the refrigerant side of WCON 2, and a first temperature and pressure sensor 7 is provided on the pipeline connecting the inlet of the compressor 1 with the solenoid valve 6 and the refrigerant side of Chiller 5. One end of the first kettle 26 is connected to the coolant side inlet of Chiller 5, and the other end of the first kettle 26 is connected to the coolant side outlet of Chiller 5. One end of the second kettle 27 is connected to the coolant side inlet of WCON 2, and the other end of the second kettle 27 is connected to the coolant side outlet of WCON 2.

[0098] like Figure 1 As shown, a first temperature sensor 12 is provided at the air outlet of the warm air core 9 in the passenger compartment HVAC assembly, a second temperature sensor 13 is provided at the air outlet of the cold air core 10 in the passenger compartment HVAC assembly, a third temperature sensor 17 is provided at the coolant inlet of the battery pack 18, and the third temperature sensor 17 is provided on the pipeline connecting the battery pack 18 and the first water pump 16, a fourth temperature sensor 19 is provided at the coolant outlet of the battery pack 18, and the fourth temperature sensor 19 is provided on the pipeline connecting the battery pack 18 and the No. 1 port of the second proportional three-way valve 15, a fifth temperature sensor 22 is provided at the coolant outlet of the electric drive system 21, and the fifth temperature sensor 22 is provided on the pipeline connecting the electric drive system 21 and the No. 10 port of the twelve-way valve 28, a sixth temperature sensor 29 is provided at the coolant side outlet of Chiller 5, and the sixth temperature sensor 29 is provided on the pipeline connecting the coolant side outlet of Chiller 5 and the inlet of the third water pump 24, WCON A seventh temperature sensor 30 is provided at the coolant side outlet of WCON 2, and the seventh temperature sensor 30 is provided on a pipeline connecting the coolant side outlet of WCON 2 and the inlet of the fourth water pump 25, and an eighth temperature sensor 31 is provided at the air inlet of the low-temperature radiator 23.

[0099] The present invention also provides a control method for a thermal management system of an electric vehicle. Using the thermal management system of an electric vehicle provided by the present invention, in a refrigerant management module, a compressor and a solenoid valve form a bypass branch. By controlling the opening of the solenoid valve and adjusting the opening and closing of the twelve-way valve, different thermal management circuits are formed to complete the cooling and heating, heat storage, dehumidification and defrosting of the passenger compartment, the heating, cooling, heat dissipation, waste heat utilization, heat storage, and self-circulation temperature equalization of the battery pack, the heat dissipation, waste heat utilization, reduced efficiency heating, and heat storage of the electric drive, and other scene modes are operated separately or in combination, so as to realize a high degree of integration of the thermal management system of the electric vehicle, including:

[0100] The refrigerant module management system includes: a first working mode of the refrigerant module, a second working mode of the refrigerant module, a third working mode of the refrigerant module, and a fourth working mode of the refrigerant module.

[0101] When the refrigerant pressure at the compressor outlet is higher than the minimum pressure allowed for the solenoid valve to open, and the ambient temperature is lower than the minimum operating temperature of the refrigerant management module, the first operating mode of the refrigerant module is started;

[0102] Among them, the minimum pressure P allowed for the solenoid valve to open 1 The minimum operating temperature of the refrigerant management module is 0.2MPa. 1 It is -15℃.

[0103] like Figure 2 As shown, when the refrigerant module management system mode is the first working mode of the refrigerant module, the electronic expansion valve 4 is closed, the compressor 1 is started at a low speed, the hot gas bypass branch solenoid valve 6 is opened, and the high-temperature and high-pressure refrigerant at the outlet of the compressor 1 enters the hot gas bypass branch, and enters the inlet of the compressor 1 after passing through the solenoid valve 6 on the hot gas bypass branch.

[0104] When the refrigerant pressure at the compressor outlet is higher than the minimum pressure allowed for the solenoid valve to open, and the refrigerant superheat at the compressor inlet is less than the set superheat for the compressor to operate reliably, the second working mode of the refrigerant module is started;

[0105] Among them, the superheat T set for the reliable operation of the compressor 2 It is 10~20℃.

[0106] like Figure 3As shown, when the refrigerant module management system mode is the second working mode of the refrigerant module, the compressor 1 is started at a low speed, the electronic expansion valve 4 is opened, the hot gas bypass branch is adjusted, and the opening of the solenoid valve 6 controls the refrigerant flow entering the hot gas bypass branch. Part of the high-temperature and high-pressure refrigerant enters the hot gas bypass branch through the outlet of the compressor 1, enters the inlet of the compressor 1 after passing through the solenoid valve 6 on the hot gas bypass branch, and enters the compressor 1 after mixing with the low-temperature and low-pressure refrigerant at the inlet of the compressor 1; the remaining high-temperature and high-pressure refrigerant enters the refrigerant side inlet of WCON 2 through the outlet of the compressor 1, flows out from the refrigerant side outlet of WCON 2, enters the inlet of the liquid storage tank 3, enters one end of the electronic expansion valve 4 through the outlet of the liquid storage tank 3, flows out through the other end of the electronic expansion valve 4 and enters the refrigerant side inlet of Chiller 5, and enters the inlet of the compressor 1 through the refrigerant side outlet of Chiller. Among them, the refrigerant temperature and pressure are fed back by the first temperature and pressure sensor 7 and the second temperature and pressure sensor 8 at the inlet and outlet of the compressor 1 to realize the distribution of the refrigerant flow entering the hot gas bypass branch and the refrigerant side inlet flow entering WCON2. When the outlet temperature pressure is higher than the allowable exhaust temperature of the compressor, the solenoid valve is opened until the exhaust temperature drops to the allowable exhaust temperature and the solenoid valve opening is fixed.

[0107] When the refrigerant pressure at the compressor outlet is higher than the maximum pressure allowed by the solenoid valve, and the superheat of the refrigerant at the compressor inlet is not less than the designed superheat for the reliable operation of the compressor, the third working mode of the refrigerant management module is started;

[0108] Among them, the maximum pressure P allowed for the solenoid valve to open 2 It is 0.5MPa.

[0109] like Figure 4 As shown, when the refrigerant module management system mode is the third refrigerant working mode, the solenoid valve 6 on the hot gas bypass branch is closed, the electronic expansion valve 4 is opened, and the high-temperature and high-pressure refrigerant enters the refrigerant side inlet of WCON 2 through the outlet of compressor 1, flows out from the refrigerant side outlet of WCON 2, enters the inlet of the liquid storage tank 3, enters one end of the electronic expansion valve 4 through the outlet of the liquid storage tank 3, flows out through the other end of the electronic expansion valve 4 into the refrigerant side inlet of Chiller 5, and enters the inlet of the compressor 1 through the refrigerant side outlet of Chiller 5.

[0110] like Figure 5 As shown, when the refrigerant module management system mode is the fourth refrigerant working mode, the solenoid valve 6 on the hot gas bypass branch is closed, the electronic expansion valve 4 is closed, and the refrigerant management module does not work.

[0111] like Figure 6 As shown, the system cycle in the third working mode of the refrigerant module management system under passenger compartment heating, battery pack heating, electric drive waste heat utilization / reduced efficiency heating, air source heat pump heating mode is:

[0112] The fourth water pump 25 is started, and the coolant is driven by the fourth water pump 25 to be sent into the coolant inlet of the heater core 9 in the passenger compartment HVAC assembly, flows out through the coolant outlet of the heater core 9 in the passenger compartment HVAC assembly and enters port 1 of the twelve-way valve 28, flows out through port 1 of the twelve-way valve 28 and enters port 11 of the twelve-way valve 28, flows out through port 11 of the twelve-way valve 28 and enters port 1 of the first proportional three-way valve 14, and part of the coolant flows out from port 2 of the first proportional three-way valve 14 and enters the inlet of the first water pump 16, flows out through the outlet of the first water pump 16 and enters the coolant inlet of the battery pack 18, and flows out through the coolant outlet of the battery pack 18 and enters the second Port 1 of the proportional three-way valve 15, part of the coolant flows out through port 2 of the second proportional three-way valve 15 and mixes with the coolant flowing out through port 3 of the first proportional three-way valve 14 to enter port 12 of the twelve-way valve 28, flows out through port 12 of the twelve-way valve 28 and enters port 3 of the twelve-way valve 28, flows out through port 3 of the twelve-way valve 28 and enters the coolant side inlet of WCON, flows out through the coolant side outlet of WCON and enters the inlet of the fourth water pump 25, part of the coolant flows out through port 3 of the second proportional three-way valve 15 and mixes with the coolant flowing out through port 2 of the first proportional three-way valve 14 to enter the inlet of the first water pump 16. Start the third water pump 24, the coolant is driven by the third water pump 24 to be sent into port No. 7 of the twelve-way valve 28, flows out through port No. 7 of the twelve-way valve 28 and enters port No. 4 of the twelve-way valve 28, flows out through port No. 4 of the twelve-way valve 28 and enters the inlet of the low-temperature radiator 23, flows out from the outlet of the low-temperature radiator 23 and enters port No. 5 of the twelve-way valve 28, flows into port No. 9 of the twelve-way valve 28, flows out through port No. 9 of the twelve-way valve 28 and enters the inlet of the second water pump 20, flows out through the outlet of the second water pump 20 and enters the coolant inlet of the electric drive system 21, flows out through the coolant outlet of the electric drive 28 and enters port No. 10 of the twelve-way valve, flows out through port No. 10 of the twelve-way valve 28 and enters port No. 6 of the twelve-way valve 28, flows out through port No. 6 of the twelve-way valve 28 and enters the coolant side inlet of Chiller 5, and then flows out through Chiller 5. 5 flows out of the coolant side outlet and enters the inlet of the third water pump 24; wherein, the coolant inlet and outlet water temperatures are fed back by the first temperature sensor and the second temperature sensor of the battery pack inlet and outlet to adjust the water outlet flow distribution ratio of the first proportional three-way valve port 2 and the water outlet flow distribution ratio of the second proportional three-way valve port 2 and the water outlet flow distribution ratio of the second proportional three-way valve port 2 and 3. When the battery pack inlet water temperature is higher than 45°C, the water inlet flow of the first proportional three-way valve port 2 is reduced, and the water inlet flow of the second proportional three-way valve port 1 is increased until the battery pack inlet water temperature reaches 25°C to 45°C.

[0113] like Figure 7 As shown, in the passenger compartment heating, battery pack waste heat utilization, electric drive waste heat utilization / reduced efficiency heating, air source heat pump heating mode, the system cycle of the refrigerant module management system in the third working mode is:

[0114] The fourth water pump 25 is started, and the coolant is driven by the fourth water pump 25 to be sent to the coolant inlet of the heater core 9 in the passenger compartment HVAC assembly of the passenger compartment thermal management module, and flows out through the coolant outlet of the heater core 9 in the passenger compartment HVAC assembly to enter the No. 1 port of the twelve-way valve 28, and flows out through the No. 1 port of the twelve-way valve 28 to enter the No. 3 port of the twelve-way valve 28; flows out through the No. 3 port of the twelve-way valve 28 to enter the coolant side inlet of the WCON 2, and flows out through the WCON 2 flows out of the coolant side outlet and enters the inlet of the fourth water pump 25; the third water pump 24 is started, and the coolant is driven by the third water pump 24 to be sent into the No. 7 port of the twelve-way valve 28, flows out through the No. 7 port of the twelve-way valve 28 and enters the No. 4 port of the twelve-way valve 28, flows out through the No. 4 port of the twelve-way valve 28 and enters the inlet of the low-temperature radiator 23, flows out through the outlet of the low-temperature radiator 23, flows through the No. 5 port of the twelve-way valve 28 and flows into the No. 11 port of the twelve-way valve 28, flows out through the No. 11 port of the twelve-way valve 28 and enters the No. 1 port of the first proportional three-way valve 14, flows out from the No. 2 port of the first proportional three-way valve 14 and enters the inlet of the first water pump 16, flows out through the inlet of the first water pump 16 and enters the coolant inlet of the battery pack 18, and flows out through the No. 11 port of the twelve-way valve 28. The coolant outlet of the pool pack 18 flows out and enters port No. 1 of the second proportional three-way valve 15, flows out through port No. 2 of the second proportional three-way valve 15 and enters port No. 12 of the twelve-way valve 28, flows out through port No. 12 of the twelve-way valve 28 and enters port No. 9 of the twelve-way valve 28, flows out through port No. 9 of the twelve-way valve 28 and enters the inlet of the second water pump 20, flows out through the outlet of the second water pump 20 and enters the coolant inlet of the electric drive system 21, flows out through the coolant outlet of the electric drive system 21 and enters port No. 10 of the twelve-way valve 28, flows out through port No. 10 of the twelve-way valve 28 and enters port No. 6 of the twelve-way valve 28, flows out through port No. 6 of the twelve-way valve 28 and flows into the coolant side inlet of Chiller 5, and flows out through the coolant side outlet of Chiller 5 and enters the third water pump 24.

[0115] like Figure 8 As shown, in the passenger compartment cooling mode and the second working mode of the refrigerant module management system, the system cycle is:

[0116] Start the third water pump 24. The coolant is driven by the third water pump 24 to be sent into the coolant inlet of the cooling air core 10 in the passenger compartment HVAC assembly, flows out through the coolant outlet of the cooling air core 10 in the passenger compartment HVAC assembly and enters port No. 8 of the twelve-way valve 28, flows out through port No. 8 of the twelve-way valve 28 and enters port No. 6 of the twelve-way valve 28, and flows out through port No. 6 of the twelve-way valve 28 and enters the third water pump 2 to complete the circulation. The coolant enters port No. 2 of the twelve-way valve 28 driven by the fourth water pump 25, flows out through port No. 2 of the twelve-way valve 28 and enters port No. 4 of the twelve-way valve 28, flows out through port No. 4 of the twelve-way valve 28 and enters the inlet of the low-temperature radiator 23, flows out through the outlet of the low-temperature radiator 23 and enters port No. 5 of the twelve-way valve 28, flows out through port No. 5 of the twelve-way valve 28 and enters port No. 3 of the twelve-way valve 28, flows out through port No. 3 of the twelve-way valve 28 and enters the coolant-side inlet of WCON 2, and flows out through the coolant-side outlet of WCON 2 and enters the inlet of the fourth water pump 25.

[0117] like Fig. 9 As shown, in the battery pack cooling mode, the system cycle of the refrigerant module management system in the second working mode is:

[0118] The third water pump 24 is started, and the coolant enters the coolant side inlet of the chiller 5 under the drive of the third water pump 24, and passes through the chiller 5. 5 flows out from the coolant side outlet and enters the inlet of the third water pump 24, flows out through the outlet of the third water pump 24 and enters port 7 of the twelve-way valve 28, flows out through port 7 of the twelve-way valve 28 and enters port 11 of the twelve-way valve 28, flows out through port 11 of the twelve-way valve 28 and enters port 1 of the first proportional three-way valve 14, flows out from port 2 of the first proportional three-way valve 14 and enters the inlet of the first water pump 16, flows out through the outlet of the first water pump 16 and enters the coolant inlet of the battery pack 18, flows out through the coolant outlet of the battery pack 18 and enters port 1 of the second proportional three-way valve 15, flows out through port 2 of the second proportional three-way valve 15 and enters port 12 of the twelve-way valve 28, flows out through port 12 of the twelve-way valve 28 and enters port 6 of the twelve-way valve 28, and flows out through port 6 of the twelve-way valve 28 and enters the coolant side inlet of Chiller 5. Start the fourth water pump 25. The coolant enters port 2 of the twelve-way valve 28 driven by the fourth water pump 25, flows out through port 2 of the twelve-way valve 28 and enters port 4 of the twelve-way valve 28, flows out through port 4 of the twelve-way valve 28 and enters the inlet of the low-temperature radiator 23, flows out through the outlet of the low-temperature radiator 23 and enters port 5 of the twelve-way valve 28, flows out through port 5 of the twelve-way valve 28 and enters port 3 of the twelve-way valve 28, flows out through port 3 of the twelve-way valve 28 and enters the coolant-side inlet of WCON 2, and flows out through the coolant-side outlet of WCON 2 and enters the inlet of the fourth water pump 25.

[0119] like Fig.10 As shown, in the battery pack cooling mode and the refrigerant module management system in the third working mode, the coolant system circulation is: the flow state is the same as the flow state of the coolant system circulation in the battery pack cooling mode and the refrigerant module management system in the second working mode.

[0120] like Fig.11 As shown, in the battery pack cooling mode, the system cycle of the refrigerant module management system in the fourth working mode is:

[0121] Start the first water pump 16. Driven by the first water pump 16, the coolant enters the coolant inlet of the battery pack 18, flows out through the coolant outlet of the battery pack 18 and enters port 1 of the second proportional three-way valve 15, flows out through port 2 of the second proportional three-way valve 15 and enters port 12 of the twelve-way valve 28, flows out through port 4 of the twelve-way valve 28 and enters the inlet of the low-temperature radiator 23, flows out through the outlet of the low-temperature radiator 23 and enters port 5 of the twelve-way valve 28, flows out through port 5 of the twelve-way valve 28 and enters port 11 of the twelve-way valve 28, flows out through port 11 of the twelve-way valve 28 and enters port 1 of the first proportional three-way valve 14, and flows out through port 2 of the first proportional three-way valve 14 and enters the inlet of the first water pump 16.

[0122] like Fig.12 As shown, the system cycle in the electric drive cooling mode and the second working mode of the refrigerant module management system is shown as follows:

[0123] Start the third water pump 24. Driven by the third water pump 24, the coolant enters the coolant side inlet of Chiller 5, flows out through the coolant side outlet of Chiller 5 and enters the inlet of the third water pump 24, flows out through the outlet of the third water pump 24 and enters port No. 7 of the twelve-way valve 28, flows out through port No. 7 of the twelve-way valve 28 and enters port No. 9 of the twelve-way valve 28, flows out through port No. 9 of the twelve-way valve 28 and enters the inlet of the second water pump 20, flows out through the outlet of the second water pump 20 and enters the coolant inlet of the electric drive system 21, flows out through the coolant outlet of the electric drive system 21 and enters port No. 10 of the twelve-way valve 28, flows out through port No. 10 of the twelve-way valve 28 and enters port No. 6 of the twelve-way valve 28, and flows out through port No. 6 of the twelve-way valve 28 and enters the coolant side inlet of Chiller 5. Start the fourth water pump 25. The coolant enters port 2 of the twelve-way valve 28 driven by the fourth water pump 25, flows out through port 2 of the twelve-way valve 28 and enters port 4 of the twelve-way valve 28, flows out through port 4 of the twelve-way valve 28 and enters the inlet of the low-temperature radiator 23, flows out through the outlet of the low-temperature radiator 23 and enters port 5 of the twelve-way valve 28, flows out through port 5 of the twelve-way valve 28 and enters port 3 of the twelve-way valve 28, flows out through port 3 of the twelve-way valve 2 and enters the coolant side inlet of WCON 2, and flows out through the coolant side outlet of WCON 2 and enters the inlet of the fourth water pump 25.

[0124] like Fig.13 As shown, in the electric drive cooling mode and the third working mode of the refrigerant module management system, the system cycle is:

[0125] The flow state of the coolant system circulation diagram is the same as the flow state of the coolant system circulation diagram in the electric drive cooling mode and the second working mode of the refrigerant module management system.

[0126] like Fig.14 As shown, in the electric drive cooling mode and the fourth working mode of the refrigerant module management system, the system cycle is:

[0127] Start the second water pump 20. Driven by the second water pump 20, the coolant enters the coolant inlet of the electric drive system 21, flows out through the coolant outlet of the electric drive system 21 and enters port No. 10 of the twelve-way valve 28, flows out through port No. 4 of the twelve-way valve 28 and enters the inlet of the low-temperature radiator 23, flows out through the outlet of the low-temperature radiator 23 and enters port No. 5 of the twelve-way valve 28, flows out through port No. 5 of the twelve-way valve 28 and enters port No. 9 of the twelve-way valve 28, and flows out through port No. 9 of the twelve-way valve 28 and enters the inlet of the second water pump 20.

[0128] like Fig.15 The system cycle shown in the passenger compartment heat storage, battery heat storage, electric drive heat storage mode, and the fourth working mode of the refrigerant module management system is:

[0129] The fourth water pump 25 is started. Driven by the fourth water pump 25, the coolant enters the heater core 9 in the passenger compartment HVAC assembly, flows out through the heater core 9 in the passenger compartment HVAC assembly and enters port 1 of the twelve-way valve 28, flows out through port 1 of the twelve-way valve 28 and enters port 9 of the twelve-way valve 28, flows out through port 9 of the twelve-way valve 28 and enters the inlet of the second water pump 20, flows out through the outlet of the second water pump 20 and enters the coolant inlet of the electric drive system 21, flows out through the coolant outlet of the electric drive system 21 and enters port 10 of the twelve-way valve 28, flows out through the The water flows out from port No. 10 and enters port No. 11 of the twelve-way valve 28, flows out through port No. 11 of the twelve-way valve 28 and enters port No. 1 of the first proportional three-way valve 14, flows out through port No. 2 of the first proportional three-way valve 14 and enters the inlet of the first water pump 16, flows out through the outlet of the first water pump 16 and enters the coolant inlet of the battery pack 18, flows out through the coolant outlet of the battery pack 18 and enters port No. 1 of the second proportional three-way valve 15, flows out through port No. 2 of the second proportional three-way valve 15 and enters port No. 12 of the twelve-way valve 28, flows out through port No. 3 of the twelve-way valve 28 and enters the coolant side inlet of WCON 2, and flows out through the coolant side outlet of WCON2 and enters the inlet of the fourth water pump 25.

[0130] like Fig.16 As shown, in the passenger compartment defrosting mode and the second working mode of the refrigerant module management system, the system cycle is:

[0131] Start the fourth water pump 25. Driven by the fourth water pump 25, the coolant enters the coolant side inlet of WCON2, flows out through the coolant side outlet of WCON 2 and enters the inlet of the fourth water pump 25, flows out through the outlet of the fourth water pump 25 and enters the passenger compartment HAVC assembly heater core 9, enters port No. 1 of the twelve-way valve 28 through the passenger compartment HAVC assembly heater core 9, flows out through port No. 1 of the twelve-way valve 28 and enters port No. 4 of the twelve-way valve 28, flows out through port No. 4 of the twelve-way valve 28 and enters the low-temperature radiator 23, flows out through the low-temperature radiator 23 and enters port No. 5 of the twelve-way valve 28, and flows out through port No. 5 of the twelve-way valve 28 and enters port No. 3 of the twelve-way valve 28. Start the third water pump 24. Driven by the third water pump 24, the coolant enters the coolant side inlet of Chiller 5, flows out through the coolant side outlet of Chiller 5 and enters the inlet of the third water pump 24, flows out through the outlet of the third water pump 24 and enters the cooling air core 10 in the passenger compartment HVAC assembly, enters the port No. 8 of the twelve-way valve 28 through the cooling air core 10 in the passenger compartment HVAC assembly, flows out through the port No. 8 of the twelve-way valve 28 and enters the port No. 6 of the twelve-way valve 28, and flows out through the port No. 6 of the twelve-way valve 28 and enters the coolant side inlet of Chiller.

[0132] like Fig.17As shown, in the passenger compartment dehumidification mode, the system cycle in the second working mode of the refrigerant module is: the circulation flow state of the coolant system is the same as the circulation flow state of the coolant system in the passenger compartment defrost mode and the second working mode of the refrigerant module management system.

[0133] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A thermal management system for an electric vehicle, characterized in that: include: A refrigerant management module and a passenger compartment thermal management module, a battery pack thermal management module, an electric drive thermal management module and a low-temperature radiator module respectively connected to the twelve-way valve; The refrigerant management module includes: compressor; WCON, which includes a refrigerant side and a coolant side, the outlet of the compressor is connected to the inlet of the refrigerant side of the WCON; A liquid storage tank, wherein the outlet of the WCON refrigerant side is connected to the inlet of the liquid storage tank; An electronic expansion valve, one end of which is connected to the outlet of the liquid storage tank; A chiller, comprising a refrigerant side and a coolant side, wherein the inlet of the chiller refrigerant side is connected to the other end of the electronic expansion valve, and the outlet of the chiller refrigerant side is connected to the inlet of the compressor; A solenoid valve, one end of which is connected to the outlet of the compressor, and the other end of which is connected to the inlet of the compressor, and a hot gas bypass branch is formed between the solenoid valve and the compressor; The passenger compartment thermal management module includes: Port No. 3 of the twelve-way valve, which is connected to the inlet of the coolant side of the WCON; a fourth water pump, the inlet of which is connected to the outlet of the coolant side of the WCON; A heater core, wherein the outlet of the fourth water pump is connected to the inlet of the heater core; Port No. 1 of the twelve-way valve is connected to the outlet of the heater core; Port No. 6 of the twelve-way valve is connected to the coolant side inlet of the chiller; A third water pump, the inlet of which is connected to the outlet of the chiller coolant side; a cold air core, the inlet of which is connected to the outlet of the third water pump; Port No. 8 of the twelve-way valve is connected to the outlet of the cold air core; The battery pack thermal management module includes: Port No. 11 and Port No. 12 of the twelve-way valve; Port No. 1 of the first proportional three-way valve is connected to port No. 11 of the twelve-way valve; Port No. 2 of the first proportional three-way valve; Port No. 3 of the first proportional three-way valve is connected to port No. 12 of the twelve-way valve; a first water pump, the inlet of which is connected to port No. 2 of the first proportional three-way valve; a battery pack, wherein a coolant inlet thereof is connected to an outlet of the first water pump; Port No. 1 of the second proportional three-way valve, which is connected to the outlet of the battery pack coolant; Port No. 3 of the second proportional three-way valve is connected to the inlet of the first water pump; Port No. 2 of the second proportional three-way valve is connected to port No. 12 of the twelve-way valve; The electric drive thermal management module includes: Ports 9 and 10 of the twelve-way valve; a second water pump, the inlet of which is connected to port No. 9 of the twelve-way valve; An electric drive system, whose coolant inlet is connected to the outlet of the second water pump, and the coolant outlet of the electric drive system is connected to port No. 10 of the twelve-way valve; The low temperature heat sink module includes: Port No. 4 of the twelve-way valve, Port No. 5 of the twelve-way valve; a low-temperature radiator, the inlet of which is connected to the No. 4 port of the twelve-way valve, and the outlet of which is connected to the No. 5 port of the twelve-way valve; Among them, the bypass branch is opened or closed by controlling the opening of the solenoid valve, and the bypass branch is combined with the twelve-way valve by adjusting the opening and closing of each port of the twelve-way valve, so as to complete the connection or disconnection between the refrigerant module and the passenger compartment thermal management module, the battery pack thermal management module, the electric drive thermal management module and the low-temperature radiator module, thereby forming different thermal management modes.

2. The electric vehicle thermal management system according to claim 1, characterized in that: Also includes: A first temperature and pressure sensor is provided on a pipeline connecting the outlet of the compressor and the solenoid valve and the refrigerant side of the WCON; The second temperature and pressure sensor is arranged on a pipeline connecting the inlet of the compressor and the solenoid valve and the chiller refrigerant side.

3. The electric vehicle thermal management system according to claim 2, characterized in that: Also includes: a first kettle, one end of which is connected to the cooling liquid side inlet of the chiller, and the other end of which is connected to the cooling liquid side outlet of the chiller; The second kettle has one end connected to the coolant side inlet of the WCON and the other end connected to the coolant side outlet of the WCON.

4. The electric vehicle thermal management system according to claim 3, characterized in that: Also includes: A first temperature sensor, which is arranged on a pipeline connecting the battery pack and the first water pump; The second temperature sensor is arranged on a pipeline connecting the battery pack and port No. 1 of the second proportional three-way valve.

5. A control method for a thermal management system of an electric vehicle, characterized in that: The electric vehicle thermal management system according to any one of claims 1 to 4 comprises: The refrigerant management module includes first to fourth working modes, and the refrigerant temperature and pressure are fed back by the first temperature and pressure sensor and the second temperature and pressure sensor to realize the switching and adjustment of different modes of the refrigerant management module; When the refrigerant pressure at the compressor outlet is higher than the minimum pressure allowed for the solenoid valve to open, and the ambient temperature is lower than the minimum operating temperature of the refrigerant management module, the first operating mode of the refrigerant module is started; Among them, the minimum pressure allowed for the solenoid valve to open is 0.2MPa, and the minimum operating temperature of the refrigerant management module is -15℃; The electronic expansion valve is closed, the compressor is started at a low speed, and the hot gas bypass branch solenoid valve is opened, so that the high-temperature and high-pressure refrigerant at the compressor outlet enters the hot gas bypass branch and enters the compressor inlet after passing through the solenoid valve on the hot gas bypass branch; When the refrigerant pressure at the compressor outlet is higher than the minimum pressure allowed for the solenoid valve to open, and the refrigerant superheat at the compressor inlet is less than the set superheat for the compressor to operate reliably, the second working mode of the refrigerant module is started; Among them, the superheat set for reliable operation of the compressor is 10-20℃; Start the compressor at a low speed, open the electronic expansion valve, adjust the opening of the hot gas bypass branch solenoid valve, control the refrigerant flow entering the hot gas bypass branch, part of the high-temperature and high-pressure refrigerant enters the hot gas bypass branch through the compressor outlet, enters the compressor inlet after passing through the solenoid valve on the hot gas bypass branch, and enters the compressor after mixing with the low-temperature and low-pressure refrigerant at the compressor inlet; the remaining high-temperature and high-pressure refrigerant enters the refrigerant side inlet of the WCON through the compressor outlet, flows out from the refrigerant side outlet of the WCON, enters the liquid storage tank inlet, enters one end of the electronic expansion valve through the liquid storage tank outlet, flows out through the other end of the electronic expansion valve into the Chiller refrigerant side inlet, and enters the compressor inlet through the Chiller refrigerant side outlet; Among them, the refrigerant temperature and pressure are fed back through the first temperature and pressure sensor and the second temperature and pressure sensor to realize the distribution of the refrigerant flow entering the hot gas bypass and the refrigerant side inlet flow entering WCON 2. When the outlet temperature and pressure are higher than the allowable exhaust temperature of the compressor, the solenoid valve is opened until the exhaust temperature drops to the allowable exhaust temperature, and the opening of the solenoid valve is fixed; When the refrigerant pressure at the compressor outlet is higher than the maximum pressure allowed by the solenoid valve, and the superheat of the refrigerant at the compressor inlet is not less than the designed superheat for the reliable operation of the compressor, the third working mode of the refrigerant management module is started: Among them, the maximum pressure allowed for the solenoid valve to open is 0.5MPa; The solenoid valve on the hot gas bypass branch is closed, the electronic expansion valve is opened, and the high-temperature and high-pressure refrigerant enters the WCON refrigerant side inlet through the compressor outlet, flows out from the WCON refrigerant side outlet, enters the liquid storage tank inlet, enters one end of the electronic expansion valve through the liquid storage tank outlet, flows out through the other end of the electronic expansion valve into the Chiller refrigerant side inlet, and enters the compressor inlet through the Chiller refrigerant side outlet; When the refrigerant module management system mode is the fourth refrigerant working mode: The solenoid valve on the hot gas bypass branch is closed, the electronic expansion valve is closed, and the refrigerant management module does not work.

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