Integrated CO2 thermal management system of electric vehicle and control method thereof

Abstract

The invention discloses an electric automobile integrated CO2 thermal management system which comprises a refrigerant loop and a cooling liquid loop. The refrigerant loop comprises a WCC, a first electronic water pump, an evaporator, a warm air core body, an electric compressor, an outdoor air cooler, a first electronic expansion valve, a second electronic expansion valve, a third electronic expansion valve, a fourth electronic expansion valve, a first stop valve, a second stop valve and a gas-liquid integrated separator; the cooling liquid loop comprises an electric drive loop and a battery loop. According to the system, integration of a cooling liquid loop is achieved, and the risk of leakage of refrigerants is reduced. The invention further discloses a control method of the integrated CO2 heat management system of the electric automobile, various working modes can be achieved, the heating and refrigerating requirements of a passenger compartment of the electric automobile are met, meanwhile, refined management such as motor cooling, waste heat recovery and cooling and heating of a power battery can be conducted, and the system is suitable for popularization and application. An integrated framework of a heat pump air conditioner, a battery and an electric drive heat management system is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal management of electric vehicles, and more particularly to an integrated CO2 thermal management system for electric vehicles and a control method thereof. Background Art

[0002] Electric vehicles are gradually replacing traditional fuel vehicles because they can reduce fossil fuel consumption and greenhouse gas emissions.

[0003] Compared with the PTC heating system, the driving range of electric vehicles equipped with R134a heat pumps is significantly improved. However, R134a has a high greenhouse effect potential (Global Warming Potential, GWP = 1300). In October 2016, the international community reached the Montreal (Kigali Amendment) to clarify the decommissioning time of hydrofluorocarbon refrigerants including R134a. In order to alleviate the greenhouse effect, there is an urgent need for a new refrigerant that is both efficient and environmentally friendly and suitable for use in low-temperature environments as an alternative.

[0004] As a natural, non-toxic refrigerant, CO2 has the advantages of high heat transfer coefficient and large heating capacity per unit volume. It shows significant advantages in low-temperature environments and vehicle applications. However, at present, the components in the CO2 thermal management system are connected by pipes, which leads to problems such as too many interfaces and unreasonable vehicle space layout. Therefore, there is an urgent need to improve the current CO2 thermal management system. Summary of the invention

[0005] The purpose of the present invention is to design and develop an integrated CO2 thermal management system for electric vehicles, which realizes the connection between the refrigerant circuit and the coolant circuit of the passenger compartment, power battery and / or drive motor through a nine-way water valve, thereby improving integration and reducing the risk of leakage.

[0006] The present invention also designs and develops a control method for an integrated CO2 thermal management system for electric vehicles. By switching different circuits according to different needs, a variety of working modes can be realized to meet the heating and cooling needs of the electric vehicle passenger compartment. At the same time, refined management such as motor cooling, waste heat recovery, and cooling and heating of power batteries can also be performed.

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

[0008] An integrated CO2 thermal management system for an electric vehicle, comprising a refrigerant circuit and a coolant circuit;

[0009] The refrigerant circuit comprises:

[0010] Electric compressors; and

[0011] A first plate heat exchanger, the refrigerant inlet end of which is connected to the exhaust end of the electric compressor;

[0012] An outdoor air cooler, one end of which is selectively connectable or disconnectable to the refrigerant outlet end of the first plate heat exchanger;

[0013] A gas-liquid integrated separator, comprising a first port, a second port, a third port and a fourth port;

[0014] Wherein, a first heat regenerator is arranged between the first port and the second port, a second heat regenerator is arranged between the third port and the fourth port, the first heat regenerator and the second heat regenerator can be selectively opened or closed, the first port is connected to the air inlet end of the electric compressor, the second port is connected to the refrigerant outlet end of the first plate heat exchanger and / or one end of the outdoor air cooler, and the third port is connected to the other end of the outdoor air cooler;

[0015] an evaporator, one end of which is selectively connected to or disconnected from the fourth port, the other end of which is selectively connected to or disconnected from the second port, and the other end of which is selectively connected to or disconnected from the refrigerant outlet of the first plate heat exchanger;

[0016] A warm air core, the liquid inlet end of which is connected to the water side outlet end of the first plate heat exchanger;

[0017] A nine-way water valve, the eighth port of which is connected to the liquid outlet of the heater core;

[0018] A first electronic water pump is arranged between the water side inlet end of the first plate heat exchanger and the ninth port of the nine-way water valve;

[0019] The second plate heat exchanger, whose two ends on the water side are respectively connected to the sixth port and the seventh port of the nine-way water valve, the refrigerant inlet end and one end and / or the fourth port of the evaporator can be selectively connected or disconnected with each other, and the refrigerant outlet end is connected to the second port;

[0020] The coolant circuit includes a battery circuit and an electric drive circuit, and the battery circuit is connected to the 4th and 5th ports of the nine-way water valve, and the electric drive circuit is connected to the 1st, 2nd and 3rd ports of the nine-way water valve.

[0021] Preferably, it also includes:

[0022] A first electronic expansion valve, which is arranged between the refrigerant outlet end of the first plate heat exchanger and the outdoor air cooler;

[0023] The second electronic expansion valve has one end connected to the refrigerant outlet end of the first plate heat exchanger, and the other end connected to the other end of the evaporator.

[0024] Preferably, it also includes:

[0025] A first stop valve, one end of which is connected to the other end of the first electronic expansion valve and one end of the outdoor air cooler, and the other end of which is connected to the second port;

[0026] The second stop valve has one end connected to the other end of the second electronic expansion valve and the other end of the evaporator, and the other end connected to the other end of the first stop valve.

[0027] Preferably, it also includes:

[0028] a third electronic expansion valve, one end of which is connected to the fourth port, and the other end of which is connected to one end of the evaporator;

[0029] The fourth electronic expansion valve has one end connected to the other end of the third electronic expansion valve and one end of the evaporator, and the other end connected to the refrigerant inlet end of the second plate heat exchanger.

[0030] Preferably, the battery circuit comprises:

[0031] An electric heater, one end of which is connected to the fourth port of the nine-way water valve;

[0032] A second electronic water pump, a suction end of which is connected to the other end of the electric heater;

[0033] The power battery has a coolant interface at one end connected to the outlet of the second electronic water pump, and a coolant interface at the other end connected to the fifth port of the nine-way water valve.

[0034] Preferably, the electric drive circuit comprises:

[0035] A third electronic water pump, a suction end of which is connected to the first port of the nine-way water valve;

[0036] A drive motor, wherein one end interface of the coolant is connected to the outlet end of the third electronic water pump, and the other end interface of the coolant is connected to the third port of the nine-way water valve;

[0037] The low-temperature heat dissipation water tank has one end connected to the second port of the nine-way water valve, and the other end connected to the suction end of the third electronic water pump and the first port of the nine-way water valve.

[0038] Preferably, it also includes:

[0039] An expansion kettle, comprising a first liquid replenishment port and a second liquid replenishment port;

[0040] Wherein, the first liquid replenishing port is connected to the low-temperature heat dissipation water tank, and the second liquid replenishing port is connected to the third electronic water pump.

[0041] Preferably, the refrigerant in the refrigerant circuit is CO2, R134a or 1234yf.

[0042] A control method for an integrated CO2 thermal management system for an electric vehicle, using the integrated CO2 thermal management system for an electric vehicle, comprises the following steps:

[0043] Step 1: Collect the ambient temperature in the vehicle, the cell temperature of the power battery, the temperature of the drive motor body and the driver's intention;

[0044] Step 2: Determine whether to start or stop the passenger compartment cooling mode or the passenger compartment heating mode according to the driver's intention, determine whether to start or stop the battery cooling mode or the battery heating mode according to the power battery cell temperature, and determine whether to start or stop the motor heat storage mode or the defrost mode according to the vehicle's ambient temperature:

[0045] Among them, if the battery cell temperature of the power battery reaches 45°C, the battery cooling mode is activated, and when the battery cell temperature of the power battery reaches 35°C, the battery cooling mode is turned off;

[0046] If the battery cell temperature of the power battery is less than 0°C, the battery heating mode is activated, and when the battery water inlet temperature is greater than or equal to 45°C, the battery heating mode is turned off;

[0047] If the temperature of the drive motor body reaches 85°C, the motor heat storage mode is activated, and when the temperature of the drive motor body is less than 80°C, the motor heat storage mode is closed;

[0048] If the ambient temperature in the car is between -15 and 0°C, the defrost mode will be activated.

[0049] Preferably, the passenger compartment cooling mode is:

[0050] The first electronic expansion valve, the third electronic expansion valve and the second stop valve are opened, and the electric compressor, the first plate heat exchanger, the first electronic expansion valve, the outdoor air cooler, the second regenerator, the third electronic expansion valve, the evaporator, the second stop valve and the second regenerator form a circuit of the passenger compartment cooling mode;

[0051] If the passenger compartment cooling mode and the battery cooling mode are started at the same time, the first electronic expansion valve, the third electronic expansion valve, the fourth electronic expansion valve, the second stop valve, the second electronic water pump and the 4th, 5th, 6th and 7th ports of the nine-way water valve are opened, and the 4th port and the 6th port of the nine-way water valve are connected, and the 5th port and the 7th port of the nine-way water valve are connected, and the electric compressor, the first plate heat exchanger, the first electronic expansion valve, the outdoor air cooler, the second regenerator, the third electronic expansion valve, the fourth electronic expansion valve, the evaporator, the second stop valve, the second regenerator and the second plate heat exchanger constitute the refrigerant circuit of the passenger compartment cooling mode and the battery cooling mode; the water side flow channel of the second plate heat exchanger, the power battery, the electric heater, the second electronic water pump and the 4th, 5th, 6th and 7th ports of the nine-way water valve constitute the coolant circuit of the passenger compartment cooling mode and the battery cooling mode;

[0052] If the passenger compartment cooling mode, battery cooling mode and motor heat storage mode are started at the same time, the first electronic expansion valve, the third electronic expansion valve, the fourth electronic expansion valve, the second stop valve, the second electronic water pump and the first, third, fourth, fifth, sixth and seventh ports of the nine-way water valve are opened, and the first port and the third port of the nine-way water valve are connected, the fourth port and the sixth port of the nine-way water valve are connected, and the fifth port and the seventh port of the nine-way water valve are connected, and the electric compressor, the first plate heat exchanger, the first electronic expansion valve, the outdoor air cooler , the second regenerator, the third electronic expansion valve, the fourth electronic expansion valve, the evaporator, the second stop valve, the second regenerator and the second plate heat exchanger constitute the refrigerant circuit of the passenger compartment cooling mode and the battery cooling mode; the water side flow channel of the second plate heat exchanger, the power battery, the electric heater, the second electronic water pump and the 4th, 5th, 6th and 7th ports of the nine-way water valve constitute the coolant circuit of the passenger compartment cooling mode and the battery cooling mode; the drive motor, the third electronic water pump and the 1st and 3rd ports of the nine-way water valve constitute the motor heat storage circuit;

[0053] If the air side heat absorption in the passenger compartment heating mode is started, the second electronic expansion valve, the third electronic expansion valve, the first stop valve, the second stop valve, the first electronic water pump and the 8th and 9th ports in the nine-way water valve are started, and the 8th and 9th ports in the nine-way water valve are connected, and the electric compressor, the first plate heat exchanger, the second electronic expansion valve, the evaporator, the third electronic expansion valve, the first regenerator, the outdoor air cooler, the first stop valve, the second stop valve, and the second regenerator constitute a refrigerant circuit in the passenger compartment heating mode; the coolant inlet and outlet ports of the first plate heat exchanger, the heater core, the first electronic water pump and the 8th and 9th ports in the nine-way water valve constitute a coolant circuit in the passenger compartment heating mode;

[0054] If the air side heat absorption in the passenger compartment heating mode and the battery heating mode are started at the same time, the second electronic expansion valve, the third electronic expansion valve, the fourth electronic expansion valve, the first stop valve, the second stop valve, the first electronic water pump, the second electronic water pump and the 4th, 5th, 6th, 7th, 8th and 9th ports of the nine-way water valve are opened, and the 4th port and the 7th port of the nine-way water valve are connected, the 5th port and the 6th port of the nine-way water valve are connected, and the 8th port and the 9th port of the nine-way water valve are connected, and the electric compressor, the first plate heat exchanger, the second electronic expansion valve, the evaporator, the second stop valve, the first electronic water pump, the second electronic water pump and the 9th port of the nine-way water valve are connected. The check valve, the third electronic expansion valve, the fourth electronic expansion valve, the second plate heat exchanger, the gas-liquid integrated separator, the outdoor air cooler and the first stop valve constitute a refrigerant circuit for absorbing heat on the air side of the passenger compartment heating mode; the coolant inlet and outlet ends of the first plate heat exchanger, the heater core, the first electronic water pump and the 8th and 9th ports of the nine-way water valve constitute a coolant circuit for absorbing heat on the air side of the passenger compartment heating mode; the coolant inlet and outlet ends of the second plate heat exchanger, the 4th, 5th, 6th and 7th ports of the nine-way water valve, the electric heater, the second electronic water pump and the power battery constitute a battery heating mode circuit;

[0055] If the water side heat absorption of the passenger compartment heating mode and the battery heating mode are started at the same time, the first, third, fourth, fifth, sixth, seventh, eighth and ninth ports of the first electronic water pump, the second electronic water pump, the third electronic water pump, the second electronic expansion valve, the third electronic expansion valve and the nine-way water valve are opened, and the first port and the seventh port of the nine-way water valve are connected, the third port and the sixth port of the nine-way water valve are connected, the fourth port and the eighth port of the nine-way water valve are connected, and the fifth port and the ninth port of the nine-way water valve are connected, and the electric compressor, the first plate heat exchanger, the second plate heat exchanger, the second plate heat exchanger, the third ... second plate heat exchanger, the second plate heat exchanger, The heater core, the first electronic water pump, the power battery, the electric heater, the second electronic water pump and the 4th, 5th, 8th and 9th ports of the nine-way water valve constitute a coolant circuit for water-side heat absorption in the battery heating and passenger compartment heating modes; the drive motor, the third electronic water pump, the second plate heat exchanger and the 1st, 3rd, 6th and 7th ports of the nine-way water valve constitute a coolant circuit for motor waste heat recovery; the electric compressor, the first plate heat exchanger, the second electronic expansion valve, the evaporator, the third electronic expansion valve, the gas-liquid integrated separator and the second plate heat exchanger constitute a refrigerant circuit;

[0056] If the water side and the air side of the passenger compartment absorb heat at the same time in the heating mode, the second electronic expansion valve, the first stop valve, the second stop valve, the third electronic expansion valve, the fourth electronic expansion valve, the first electronic water pump, the third electronic water pump and the 1st, 3rd, 6th, 7th, 8th and 9th ports of the nine-way water valve are opened, and the 1st port and the 7th port of the nine-way water valve are connected, the 3rd port and the 6th port of the nine-way water valve are connected, the 8th port and the 9th port of the nine-way water valve are connected, and the electric compressor, the first plate heat exchanger, the first plate heat exchanger, the second plate heat exchanger, the third plate heat exchanger, the fourth plate heat exchanger, the first plate heat exchanger, the third ... The second electronic expansion valve, the evaporator, the second stop valve, the third electronic expansion valve, the fourth electronic expansion valve, the second plate heat exchanger, the outdoor air cooler, the gas-liquid integrated separator and the first stop valve constitute a refrigerant circuit; the drive motor, the third electronic water pump, the second plate heat exchanger and the 3rd and 6th, 7th and 1st ports of the nine-way water valve constitute a coolant circuit for motor waste heat recovery; the heater core, the first plate heat exchanger, the first electronic water pump and the 8th and 9th ports of the nine-way water valve constitute a coolant circuit for passenger compartment heating;

[0057] If the defrost mode is started, the first electronic expansion valve, the third electronic expansion valve and the fourth electronic expansion valve are opened, and the electric compressor, the first plate heat exchanger, the first electronic expansion valve, the outdoor air cooler, the gas-liquid integrated separator, the third electronic expansion valve, the fourth electronic expansion valve and the second plate heat exchanger form a defrost circuit.

[0058] The beneficial effects of the present invention are:

[0059] (1) The present invention designs and develops an integrated CO2 thermal management system for electric vehicles, which integrates the design of the CO2 thermal management system, not only solving the space layout problem of the entire vehicle, but also reducing the risk of refrigerant leakage.

[0060] (2) The control method of the integrated CO2 thermal management system for electric vehicles designed and developed by the present invention interconnects the electric drive circuit, the heat pump system and the battery circuit, and can transfer the heat generated in the electric drive circuit to the battery circuit, thereby achieving battery insulation and improving the battery discharge capacity. Different circuits can be switched according to different needs to achieve multiple working modes to meet the heating and cooling needs of the electric vehicle passenger compartment. At the same time, it can also perform refined management of motor cooling, waste heat recovery, and cooling and heating of power batteries, thereby realizing an integrated architecture of heat pump air conditioning, power batteries and electric drive thermal management system. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 It is a schematic diagram of the structure of the integrated CO2 thermal management system for electric vehicles according to the present invention.

[0062] Figure 2 This is a schematic diagram of the operation of the passenger compartment cooling mode of the present invention.

[0063] Figure 3 It is a schematic diagram of the operation of the passenger compartment cooling mode and the battery cooling mode of the present invention.

[0064] Figure 4 It is a working schematic diagram of the passenger compartment cooling mode, battery cooling mode and motor heat storage mode of the present invention.

[0065] Figure 5 It is a schematic diagram of the operation of air-side heat absorption in the passenger compartment heating mode of the present invention.

[0066] Figure 6 It is a schematic diagram of the operation of the air side heat absorption mode and the battery heating mode of the passenger compartment heating mode according to the present invention.

[0067] Figure 7 It is a working schematic diagram of the water side heat absorption mode and the battery heating mode of the passenger compartment heating mode according to the present invention.

[0068] Figure 8 This is a schematic diagram of the operation of the heating mode of the present invention in which the water side and the air side absorb heat simultaneously.

[0069] Fig. 9 It is a working schematic diagram of the defrost mode of the present invention. DETAILED DESCRIPTION

[0070] The present invention is further described in detail below so that those skilled in the art can implement it according to the description.

[0071] like Figure 1 As shown, an integrated CO2 thermal management system for an electric vehicle provided by the present invention includes a refrigerant circuit and a coolant circuit, wherein the refrigerant circuit includes: an electric compressor 101, a first plate heat exchanger (WCC) 102, a first electronic expansion valve 111, a second electronic expansion valve 112, an outdoor air cooler 120, a gas-liquid integrated separator 130, a first stop valve 141, a second stop valve 142, a third electronic expansion valve 151, a fourth electronic expansion valve 152, an evaporator 161, a heater core 162, and a nine-way water valve 170; the coolant circuit includes a battery circuit and an electric drive circuit, and the ports of the nine-way water valve 170 couple the battery circuit, the electric drive circuit and the passenger compartment circuit respectively.

[0072] Among them, the gas-liquid integrated separator 130 is internally provided with a first heat regenerator 131 and a second heat regenerator 132, so that the gas-liquid integrated separator 130 has a heat recovery function, and the first heat regenerator 131 is provided with a first port and a second port, and the second heat regenerator 132 is provided with a third port and a fourth port, and the first heat regenerator 131 and the second heat regenerator 132 can be selectively opened or closed; the passenger compartment circuit is mainly composed of an evaporator 161 and a heater core 162.

[0073] The battery circuit includes a power battery 201 , an electric heater (PTC) 202 , a second electronic water pump 182 and a second plate heat exchanger (Chiller) 210 ; the electric drive circuit includes a drive motor 221 , a low-temperature heat dissipation water tank 222 and a third electronic water pump 183 .

[0074] The exhaust end of the electric compressor 101 is connected to the refrigerant inlet end of the WCC102, the refrigerant outlet end of the WCC102 is connected to the first electronic expansion valve 111 and one end of the second electronic expansion valve 112 at the same time, the other end of the first electronic expansion valve 111 is connected to one end of the outdoor air cooler 120 and one end of the first stop valve 141 at the same time, the other end of the outdoor air cooler 120 is connected to the third port of the second regenerator 132, the fourth port of the second regenerator 132 is connected to one end of the third electronic expansion valve 151, and the other end of the third electronic expansion valve 151 is connected to the One end of the fourth electronic expansion valve 152 is connected to one end of the evaporator 161, and the other end of the evaporator 161 is simultaneously connected to the other end of the second electronic expansion valve 112 and one end of the second stop valve 142, the other end of the fourth electronic expansion valve 152 is connected to the refrigerant inlet end of Chiller 210, the other end of the first stop valve 141, the other end of the second stop valve 142, the refrigerant outlet end of Chiller 210 and the second port of the second regenerator 131 are simultaneously connected, and the first port of the second regenerator 131 is connected to the air intake end of the electric compressor 101.

[0075] The ports of the nine-way water valve 170 are respectively connected to the power battery 201, PTC 202, drive motor 221, low-temperature cooling water tank 222, third electronic water pump 183, Chiller 210, heater core 162 and first electronic water pump 181; wherein, the heater core 162 and the first electronic water pump 181 constitute a passenger compartment heating circuit through the ports of the nine-way water valve 170, specifically: the suction end of the first electronic water pump 181 is connected to the 9th port of the nine-way water valve 170, and the outlet end is connected to the water side inlet end of the WCC 102, the water side outlet end of the WCC 102 is connected to the liquid inlet end of the heater core 162, and the liquid outlet end of the heater core 162 is connected to the 8th port of the nine-way water valve 170; the battery circuit and the electric drive circuit are both connected to Chiller 210 through the ports of the nine-way water valve 170, specifically: the two ends of the water side of Chiller 210 are respectively connected to the nine-way The sixth port and the seventh port of the water valve 170 are connected, one end of the PTC 202 is connected to the fourth port of the nine-way water valve 170, and the other end is connected to the suction end of the second electronic water pump 182, the outlet end of the second electronic water pump 182 is connected to the coolant interface at one end of the power battery 201, and the coolant interface at the other end of the power battery 201 is connected to the fifth port of the nine-way water valve 170, the suction end of the third electronic water pump 183, the first port of the nine-way water valve 170 and the low-temperature heat dissipation water tank 222 are connected at the same time, the outlet end is connected to the coolant interface at one end of the drive motor 221, the coolant interface at the other end of the drive motor 221 is connected to the third port of the nine-way water valve 170, and the low-temperature heat dissipation water tank 222 is connected to the second port of the nine-way water valve 170, and then the battery circuit, the electric drive circuit and / or the passenger compartment circuit are connected and disconnected by the connection and disconnection between the ports of the nine-way water valve 170.

[0076] In this embodiment, the refrigerant circuit and the coolant circuit are connected via WCC102 and Chiller210.

[0077] In this embodiment, an expansion kettle 230 is also included, which is provided with two fluid replenishment ports (a first fluid replenishment port and a second fluid replenishment port). The first fluid replenishment port is connected to the low-temperature heat dissipation water tank 222 through a water pipe, and the second fluid replenishment port is connected to the third electronic water pump 183 through a water pipe.

[0078] The first electronic expansion valve 111, the second electronic expansion valve 112, the third electronic expansion valve 151 and the fourth electronic expansion valve 152 are all integrated valves; the first stop valve 141 and the second stop valve 142 are both integrated valves; the first electronic water pump 181, the second electronic water pump 182 and the third electronic water pump 183 can all be replaced according to the required flow rate.

[0079] The refrigerant circuit is provided with a refrigerant. In the present embodiment, the refrigerant is CO2, and other alternative refrigerants such as R134a and 1234yf may also be used.

[0080] In this embodiment, a temperature and pressure sensor is provided in the refrigerant circuit for monitoring parameter changes of components; and a water temperature sensor is provided in the coolant circuit for monitoring changes in water temperature parameters.

[0081] The present invention designs and develops an integrated CO2 thermal management system for electric vehicles, which is highly integrated. The extremely small installation space reduces the system loss caused by pipeline pressure drop, significantly reduces the difficulty of spatial layout of the entire vehicle system, and reduces the risk of refrigerant leakage. The thermal management system is not only compatible with 1234yf, but also applicable to low-GWP mixed refrigerants, ensuring the compatibility of the heat pipe system and reducing development costs.

[0082] The present invention also provides a control method for an integrated CO2 thermal management system for an electric vehicle, using the integrated CO2 thermal management system for an electric vehicle, comprising the following steps:

[0083] Step 1: Collect the ambient temperature in the vehicle, the cell temperature of the power battery, the temperature of the drive motor body and the driver's intention;

[0084] Wherein, the vehicle interior ambient temperature is collected by a sensor;

[0085] Step 2: Determine whether to start or stop the passenger compartment cooling mode or the passenger compartment heating mode according to the driver's intention, determine whether to start or stop the battery cooling mode or the battery heating mode according to the power battery cell temperature, and determine whether to start or stop the motor heat storage mode or the defrost mode according to the vehicle's ambient temperature:

[0086] like Figure 2 As shown, if the passenger compartment cooling mode is started, the first electronic expansion valve 111, the third electronic expansion valve 151 and the second stop valve 142 are opened, and the electric compressor 101, WCC102, the first electronic expansion valve 111, the outdoor air cooler 120, the second regenerator 132, the third electronic expansion valve 151, the evaporator 161, the second stop valve 142 and the second regenerator 131 constitute a circuit of the passenger compartment cooling mode. The superheat at the outlet of the evaporator 161 is controlled by controlling the opening of the third electronic expansion valve 151, and it also plays a role in adjusting the exhaust pressure and exhaust temperature of the electric compressor 101.

[0087] The superheat at the outlet of the evaporator 161 is controlled by controlling the opening of the third electronic expansion valve 151 , and the exhaust pressure and exhaust temperature of the electric compressor 101 are also regulated.

[0088] like Figure 3 As shown, if the cell temperature of the power battery reaches 45°C, the battery cooling mode is activated, and when the cell temperature of the power battery reaches 35°C, the battery cooling mode is turned off;

[0089] If the passenger compartment cooling mode and the battery cooling mode are started at the same time, the first electronic expansion valve 111, the third electronic expansion valve 151, the fourth electronic expansion valve 152, the second stop valve 142, the second electronic water pump 182 and the 4th, 5th, 6th and 7th ports of the nine-way water valve 170 are opened, and the 4th port and the 6th port of the nine-way water valve 170 are connected, and the 5th port and the 7th port of the nine-way water valve 170 are connected, and the electric compressor 101, WCC102, the first electronic expansion valve 111, the outdoor air cooler 1 20. The second regenerator 132, the third electronic expansion valve 151, the fourth electronic expansion valve 152, the evaporator 161, the second stop valve 142, the second regenerator 131 and Chiller 170 constitute a refrigerant circuit for the passenger compartment cooling mode and the battery cooling mode; the water side flow channel of Chiller 170, the power battery 201, the PTC 202, the second electronic water pump 182 and the 4th, 5th, 6th and 7th ports of the nine-way water valve 170 constitute a coolant circuit for the passenger compartment cooling mode and the battery cooling mode.

[0090] Among them, the third electronic expansion valve 151 and the fourth electronic expansion valve 152 control the opening of the electronic expansion valve according to the cooling requirements of the power battery 201 and the passenger compartment. When the cooling demand of the power battery 201 is large, the power battery circuit is given priority, and the opening of the fourth electronic expansion valve 152 is increased; when the cooling demand of the passenger compartment is large, the passenger compartment circuit is given priority, the opening of the third electronic expansion valve 151 is increased, and the fourth electronic expansion valve 152 is controlled according to the superheat of the Chiller 210 outlet; the second electronic water pump 182 controls the flow rate according to the outlet water temperature of the power battery 201, that is, based on the outlet water temperature of the power battery 201 being around 35°C, thereby satisfying "large flow and small temperature difference".

[0091] like Figure 4 As shown, if the temperature of the drive motor body reaches 85°C, the motor heat storage mode is started, and when the temperature of the drive motor body is less than 80°C, the motor heat storage mode is turned off;

[0092] If the passenger compartment cooling mode, the battery cooling mode and the motor heat storage mode are started at the same time, the first electronic expansion valve 111, the third electronic expansion valve 151, the fourth electronic expansion valve 152, the second stop valve 142, the second electronic water pump 182 and the first, third, fourth, fifth, sixth and seventh ports of the nine-way water valve 170 are opened, and the first port and the third port of the nine-way water valve 170 are connected, the fourth port and the sixth port of the nine-way water valve 170 are connected, and the fifth port and the seventh port of the nine-way water valve 170 are connected, and the electric compressor 101, WCC102, the first electronic expansion valve 111, the outdoor air cooler 120, the second return The heat exchanger 132, the third electronic expansion valve 151, the fourth electronic expansion valve 152, the evaporator 161, the second stop valve 142, the second heat exchanger 131 and the Chiller 170 constitute the refrigerant circuit of the passenger compartment cooling mode and the battery cooling mode; the water side flow channel of the Chiller 170, the power battery 201, the PTC 202, the second electronic water pump 182 and the 4th, 5th, 6th and 7th ports of the nine-way water valve 170 constitute the coolant circuit of the passenger compartment cooling mode and the battery cooling mode; the drive motor 221, the third electronic water pump 183 and the 1st and 3rd ports of the nine-way water valve 170 constitute the motor heat storage circuit.

[0093] like Figure 5 As shown, if the air side heat absorption in the passenger compartment heating mode is started, the second electronic expansion valve 112, the third electronic expansion valve 151, the first stop valve 141, the second stop valve 142, the first electronic water pump 181 and the 8th and 9th ports in the nine-way water valve 170 are started, and the 8th port and the 9th port in the nine-way water valve 170 are connected, and the electric compressor 101, WCC102, the second electronic expansion valve 112, the evaporator 161, the third electronic expansion valve 151, the first regenerator 132, the outdoor air cooler 120, the first stop valve 141, the second stop valve 142, and the second regenerator 131 constitute a refrigerant circuit in the passenger compartment heating mode; the coolant inlet and outlet ends of WCC102, the heater core 162, the first electronic water pump 181 and the 8th and 9th ports in the nine-way water valve 170 constitute a coolant circuit in the passenger compartment heating mode.

[0094] The first electronic water pump 181 controls the outlet water temperature of the heater core 162 to adjust the flow rate, and the third electronic expansion valve 151 and the second electronic expansion valve 112 cooperate to control the pressure state of the refrigerant side.

[0095] like Figure 6 As shown, if the cell temperature of the power battery is less than 0°C, the battery heating mode is activated, and when the battery water inlet temperature is greater than or equal to 45°C, the battery heating mode is turned off;

[0096] If the air side heat absorption mode of the passenger compartment heating mode and the battery heating mode are started at the same time, the second electronic expansion valve 112, the third electronic expansion valve 151, the fourth electronic expansion valve 152, the first stop valve 141, the second stop valve 142, the first electronic water pump 181, the second electronic water pump 182 and the 4th, 5th, 6th, 7th, 8th and 9th ports of the nine-way water valve 170 are opened, and the 4th port and the 7th port of the nine-way water valve 170 are connected, the 5th port and the 6th port of the nine-way water valve 170 are connected, and the 8th port and the 9th port of the nine-way water valve 170 are connected, and the electric compressor 101, WCC102, the second electronic expansion valve 112, the evaporator 161, the second stop valve 141, the second stop valve 142, the first electronic water pump 181, the second electronic water pump 182 and the 9th ports of the nine-way water valve 170 are opened. The three electronic expansion valves 151, the fourth electronic expansion valve 152, the first regenerator 132, the outdoor air cooler 120, the first stop valve 141, the second stop valve 142, the second regenerator 131, and Chiller 210 constitute the refrigerant circuit of the passenger compartment heating mode; the coolant inlet and outlet ends of WCC 102, the heater core 162, the first electronic water pump 181, and the 8th and 9th ports of the nine-way water valve 170 constitute the coolant circuit of the passenger compartment heating mode; the coolant inlet and outlet ends of Chiller 210, ports 5 and 6, 7 and 4 of the nine-way water valve, PTC 202, the second electronic water pump 182, and the power battery 201 constitute the battery heating mode circuit.

[0097] Among them, the first electronic water pump 181 and the second electronic water pump 182 respectively control the water outlet temperature of the heater core 162 and the power battery 201 to adjust the flow rate, and the third electronic expansion valve 151 and the fourth electronic expansion valve 152 control the opening of the electronic expansion valve according to the heating requirements of the power battery 201 and the passenger compartment. When the heating demand of the power battery 201 is large, the power battery circuit is given priority, and the opening of the fourth electronic expansion valve 152 increases; when the heating demand of the passenger compartment is large, the passenger compartment circuit is given priority, the opening of the third electronic expansion valve 151 increases, and the fourth electronic expansion valve 152 takes the evaporation temperature as the control target.

[0098] like Figure 7 As shown, the water side heat absorption in the passenger compartment heating mode and the battery heating mode are started, and the electric compressor 101, WCC102, the second electronic expansion valve 112, the evaporator 161, the third electronic expansion valve 151, the fourth electronic expansion valve 152, the outdoor air cooler 120, the first stop valve 141, the second stop valve 142, the gas-liquid integrated separator 130, and the Chiller210 constitute the refrigerant circuit of the passenger compartment heating mode; the coolant inlet and outlet ends of the WCC102, the heater core 162, the first electronic water pump 181, and the 8th and 9th ports of the nine-way water valve 170 constitute the coolant circuit of the passenger compartment heating mode; the coolant inlet and outlet ends of the Chiller210, ports 5 and 6, 7 and 4 of the nine-way water valve 170, the PTC202, the second electronic water pump 182, and the power battery 201 constitute the battery heating mode circuit.

[0099] The first electronic water pump 181 , the second electronic water pump 182 and the third electronic water pump 183 respectively control the outlet water temperature of the heater core 162 , the power battery 201 and the drive motor 221 to adjust the flow rate.

[0100] like Figure 8 As shown, in the passenger compartment heating mode, the water side and the air side absorb heat at the same time, and the electric compressor 101, WCC102, the second electronic expansion valve 112, the evaporator 161, the third electronic expansion valve 151, the fourth electronic expansion valve 152, Chiller210, the outdoor air cooler 120, the gas-liquid integrated separator 130 and the first stop valve 141 constitute a refrigerant circuit; the drive motor 221, the third electronic water pump 183, Chiller210 and the 3rd and 6th, 7th and 1st ports of the nine-way water valve 170 constitute a coolant circuit for motor waste heat recovery. The heater core 162, the first electronic water pump 181 and the 8th and 9th ports of the nine-way water valve 170 constitute a coolant circuit for passenger compartment heating.

[0101] In the passenger compartment heating mode, the gas-liquid integrated separator 130 does not need to use the heat recovery function.

[0102] like Fig. 9 As shown, if the ambient temperature in the vehicle is between -15 and 0°C, the defrost mode is started, the first electronic expansion valve 111, the third electronic expansion valve 151 and the fourth electronic expansion valve 152 are opened, and the electric compressor 101, WCC102, the first electronic expansion valve 111, the outdoor air cooler 120, the gas-liquid integrated separator 130, the third electronic expansion valve 151, the fourth electronic expansion valve 152 and Chiller210 constitute a defrost circuit, wherein the gas-liquid integrated separator 130 does not need to use the heat recovery function.

[0103] The present invention designs and develops a control method for an integrated CO2 thermal management system for electric vehicles, which interconnects an electric drive circuit, a heat pump system and a battery circuit, and can transfer the heat generated in the electric drive circuit to the battery circuit, thereby achieving battery insulation and improving the battery discharge capacity. Different circuits can be converted according to different needs to achieve multiple working modes to meet the heating and cooling needs of the electric vehicle passenger compartment. At the same time, it can also perform refined management of motor cooling, waste heat recovery, and cooling and heating of power batteries, thereby realizing an integrated architecture of heat pump air conditioning, power batteries and electric drive thermal management systems.

[0104] 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. 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 embodiments shown and described herein.

Claims

1. An integrated CO2 thermal management system for electric vehicles, characterized in that: Includes a refrigerant circuit and a coolant circuit; The refrigerant circuit comprises: Electric compressors; and A first plate heat exchanger, the refrigerant inlet end of which is connected to the exhaust end of the electric compressor; An outdoor air cooler, one end of which is selectively connectable or disconnectable to the refrigerant outlet end of the first plate heat exchanger; A gas-liquid integrated separator, comprising a first port, a second port, a third port and a fourth port; Wherein, a first heat regenerator is arranged between the first port and the second port, a second heat regenerator is arranged between the third port and the fourth port, the first heat regenerator and the second heat regenerator can be selectively opened or closed, the first port is connected to the air inlet end of the electric compressor, the second port is connected to the refrigerant outlet end of the first plate heat exchanger and / or one end of the outdoor air cooler, and the third port is connected to the other end of the outdoor air cooler; an evaporator, one end of which is selectively connected to or disconnected from the fourth port, the other end of which is selectively connected to or disconnected from the second port, and the other end of which is selectively connected to or disconnected from the refrigerant outlet of the first plate heat exchanger; A warm air core, the liquid inlet end of which is connected to the water side outlet end of the first plate heat exchanger; A nine-way water valve, the eighth port of which is connected to the liquid outlet of the heater core; A first electronic water pump is arranged between the water side inlet end of the first plate heat exchanger and the ninth port of the nine-way water valve; The second plate heat exchanger, whose two ends on the water side are respectively connected to the sixth port and the seventh port of the nine-way water valve, the refrigerant inlet end and one end and / or the fourth port of the evaporator can be selectively connected or disconnected with each other, and the refrigerant outlet end is connected to the second port; The coolant circuit includes a battery circuit and an electric drive circuit, and the battery circuit is connected to the 4th and 5th ports of the nine-way water valve, and the electric drive circuit is connected to the 1st, 2nd and 3rd ports of the nine-way water valve.

2. The integrated CO2 thermal management system for electric vehicles as claimed in claim 1, characterized in that: Also includes: A first electronic expansion valve, which is arranged between the refrigerant outlet end of the first plate heat exchanger and the outdoor air cooler; The second electronic expansion valve has one end connected to the refrigerant outlet end of the first plate heat exchanger, and the other end connected to the other end of the evaporator.

3. The integrated CO2 thermal management system for electric vehicles as claimed in claim 2, characterized in that: Also includes: A first stop valve, one end of which is connected to the other end of the first electronic expansion valve and one end of the outdoor air cooler, and the other end of which is connected to the second port; The second stop valve has one end connected to the other end of the second electronic expansion valve and the other end of the evaporator, and the other end connected to the other end of the first stop valve.

4. The integrated CO2 thermal management system for electric vehicles as claimed in claim 3, characterized in that: Also includes: a third electronic expansion valve, one end of which is connected to the fourth port, and the other end of which is connected to one end of the evaporator; The fourth electronic expansion valve has one end connected to the other end of the third electronic expansion valve and one end of the evaporator, and the other end connected to the refrigerant inlet end of the second plate heat exchanger.

5. The integrated CO2 thermal management system for electric vehicles as claimed in claim 4, characterized in that: The battery circuit comprises: An electric heater, one end of which is connected to the fourth port of the nine-way water valve; A second electronic water pump, a suction end of which is connected to the other end of the electric heater; The power battery has a coolant interface at one end connected to the outlet of the second electronic water pump, and a coolant interface at the other end connected to the fifth port of the nine-way water valve.

6. The integrated CO2 thermal management system for electric vehicles as claimed in claim 5, characterized in that: The electric drive circuit comprises: A third electronic water pump, a suction end of which is connected to the first port of the nine-way water valve; A drive motor, wherein one end interface of the coolant is connected to the outlet end of the third electronic water pump, and the other end interface of the coolant is connected to the third port of the nine-way water valve; The low-temperature heat dissipation water tank has one end connected to the second port of the nine-way water valve, and the other end connected to the suction end of the third electronic water pump and the first port of the nine-way water valve.

7. The integrated CO2 thermal management system for electric vehicles as claimed in claim 6, characterized in that: Also includes: An expansion kettle, comprising a first liquid replenishment port and a second liquid replenishment port; Wherein, the first liquid replenishing port is connected to the low-temperature heat dissipation water tank, and the second liquid replenishing port is connected to the third electronic water pump.

8. The integrated CO2 thermal management system for electric vehicles as claimed in claim 7, characterized in that: The refrigerant in the refrigerant circuit is CO2, R134a or 1234yf.

9. A control method for an integrated CO2 thermal management system for an electric vehicle, using the integrated CO2 thermal management system for an electric vehicle as claimed in any one of claims 1 to 8, characterized in that: The steps include: Step 1: Collect the ambient temperature in the vehicle, the cell temperature of the power battery, the temperature of the drive motor body and the driver's intention; Step 2: Determine whether to start or stop the passenger compartment cooling mode or the passenger compartment heating mode according to the driver's intention, determine whether to start or stop the battery cooling mode or the battery heating mode according to the power battery cell temperature, and determine whether to start or stop the motor heat storage mode or the defrost mode according to the vehicle's ambient temperature: Among them, if the battery cell temperature of the power battery reaches 45°C, the battery cooling mode is activated, and when the battery cell temperature of the power battery reaches 35°C, the battery cooling mode is turned off; If the battery cell temperature of the power battery is less than 0°C, the battery heating mode is activated, and when the battery water inlet temperature is greater than or equal to 45°C, the battery heating mode is turned off; If the temperature of the drive motor body reaches 85°C, the motor heat storage mode is activated, and when the temperature of the drive motor body is less than 80°C, the motor heat storage mode is closed; If the ambient temperature in the car is between -15 and 0°C, the defrost mode will be activated.

10. The control method of the integrated CO2 thermal management system for electric vehicles as claimed in claim 7, characterized in that: The passenger compartment cooling mode is: The first electronic expansion valve, the third electronic expansion valve and the second stop valve are opened, and the electric compressor, the first plate heat exchanger, the first electronic expansion valve, the outdoor air cooler, the second regenerator, the third electronic expansion valve, the evaporator, the second stop valve and the second regenerator form a circuit of the passenger compartment cooling mode; If the passenger compartment cooling mode and the battery cooling mode are started at the same time, the first electronic expansion valve, the third electronic expansion valve, the fourth electronic expansion valve, the second stop valve, the second electronic water pump and the 4th, 5th, 6th and 7th ports of the nine-way water valve are opened, and the 4th port and the 6th port of the nine-way water valve are connected, and the 5th port and the 7th port of the nine-way water valve are connected, and the electric compressor, the first plate heat exchanger, the first electronic expansion valve, the outdoor air cooler, the second regenerator, the third electronic expansion valve, the fourth electronic expansion valve, the evaporator, the second stop valve, the second regenerator and the second plate heat exchanger constitute the refrigerant circuit of the passenger compartment cooling mode and the battery cooling mode; the water side flow channel of the second plate heat exchanger, the power battery, the electric heater, the second electronic water pump and the 4th, 5th, 6th and 7th ports of the nine-way water valve constitute the coolant circuit of the passenger compartment cooling mode and the battery cooling mode; If the passenger compartment cooling mode, battery cooling mode and motor heat storage mode are started at the same time, the first electronic expansion valve, the third electronic expansion valve, the fourth electronic expansion valve, the second stop valve, the second electronic water pump and the first, third, fourth, fifth, sixth and seventh ports of the nine-way water valve are opened, and the first port and the third port of the nine-way water valve are connected, the fourth port and the sixth port of the nine-way water valve are connected, and the fifth port and the seventh port of the nine-way water valve are connected, and the electric compressor, the first plate heat exchanger, the first electronic expansion valve, the outdoor air cooler , the second regenerator, the third electronic expansion valve, the fourth electronic expansion valve, the evaporator, the second stop valve, the second regenerator and the second plate heat exchanger constitute the refrigerant circuit of the passenger compartment cooling mode and the battery cooling mode; the water side flow channel of the second plate heat exchanger, the power battery, the electric heater, the second electronic water pump and the 4th, 5th, 6th and 7th ports of the nine-way water valve constitute the coolant circuit of the passenger compartment cooling mode and the battery cooling mode; the drive motor, the third electronic water pump and the 1st and 3rd ports of the nine-way water valve constitute the motor heat storage circuit; If the air side heat absorption in the passenger compartment heating mode is started, the second electronic expansion valve, the third electronic expansion valve, the first stop valve, the second stop valve, the first electronic water pump and the 8th and 9th ports in the nine-way water valve are started, and the 8th and 9th ports in the nine-way water valve are connected, and the electric compressor, the first plate heat exchanger, the second electronic expansion valve, the evaporator, the third electronic expansion valve, the first regenerator, the outdoor air cooler, the first stop valve, the second stop valve, and the second regenerator constitute a refrigerant circuit in the passenger compartment heating mode; the coolant inlet and outlet ports of the first plate heat exchanger, the heater core, the first electronic water pump and the 8th and 9th ports in the nine-way water valve constitute a coolant circuit in the passenger compartment heating mode; If the air side heat absorption in the passenger compartment heating mode and the battery heating mode are started at the same time, the second electronic expansion valve, the third electronic expansion valve, the fourth electronic expansion valve, the first stop valve, the second stop valve, the first electronic water pump, the second electronic water pump and the 4th, 5th, 6th, 7th, 8th and 9th ports of the nine-way water valve are opened, and the 4th port and the 7th port of the nine-way water valve are connected, the 5th port and the 6th port of the nine-way water valve are connected, and the 8th port and the 9th port of the nine-way water valve are connected, and the electric compressor, the first plate heat exchanger, the second electronic expansion valve, the evaporator, the second stop valve, the first electronic water pump, the second electronic water pump and the 9th port of the nine-way water valve are connected. The check valve, the third electronic expansion valve, the fourth electronic expansion valve, the second plate heat exchanger, the gas-liquid integrated separator, the outdoor air cooler and the first stop valve constitute a refrigerant circuit for absorbing heat on the air side of the passenger compartment heating mode; the coolant inlet and outlet ends of the first plate heat exchanger, the heater core, the first electronic water pump and the 8th and 9th ports of the nine-way water valve constitute a coolant circuit for absorbing heat on the air side of the passenger compartment heating mode; the coolant inlet and outlet ends of the second plate heat exchanger, the 4th, 5th, 6th and 7th ports of the nine-way water valve, the electric heater, the second electronic water pump and the power battery constitute a battery heating mode circuit; If the water side heat absorption of the passenger compartment heating mode and the battery heating mode are started at the same time, the first, third, fourth, fifth, sixth, seventh, eighth and ninth ports of the first electronic water pump, the second electronic water pump, the third electronic water pump, the second electronic expansion valve, the third electronic expansion valve and the nine-way water valve are opened, and the first port and the seventh port of the nine-way water valve are connected, the third port and the sixth port of the nine-way water valve are connected, the fourth port and the eighth port of the nine-way water valve are connected, and the fifth port and the ninth port of the nine-way water valve are connected, and the electric compressor, the first plate heat exchanger, the second plate heat exchanger, the second plate heat exchanger, the third ... second plate heat exchanger, the second plate heat exchanger, The heater core, the first electronic water pump, the power battery, the electric heater, the second electronic water pump and the 4th, 5th, 8th and 9th ports of the nine-way water valve constitute a coolant circuit for water-side heat absorption in the battery heating and passenger compartment heating modes; the drive motor, the third electronic water pump, the second plate heat exchanger and the 1st, 3rd, 6th and 7th ports of the nine-way water valve constitute a coolant circuit for motor waste heat recovery; the electric compressor, the first plate heat exchanger, the second electronic expansion valve, the evaporator, the third electronic expansion valve, the gas-liquid integrated separator and the second plate heat exchanger constitute a refrigerant circuit; If the water side and the air side of the passenger compartment absorb heat at the same time in the heating mode, the second electronic expansion valve, the first stop valve, the second stop valve, the third electronic expansion valve, the fourth electronic expansion valve, the first electronic water pump, the third electronic water pump and the 1st, 3rd, 6th, 7th, 8th and 9th ports of the nine-way water valve are opened, and the 1st port and the 7th port of the nine-way water valve are connected, the 3rd port and the 6th port of the nine-way water valve are connected, the 8th port and the 9th port of the nine-way water valve are connected, and the electric compressor, the first plate heat exchanger, the first plate heat exchanger, the second plate heat exchanger, the third plate heat exchanger, the fourth plate heat exchanger, the first plate heat exchanger, the third ... The second electronic expansion valve, the evaporator, the second stop valve, the third electronic expansion valve, the fourth electronic expansion valve, the second plate heat exchanger, the outdoor air cooler, the gas-liquid integrated separator and the first stop valve constitute a refrigerant circuit; the drive motor, the third electronic water pump, the second plate heat exchanger and the 3rd and 6th, 7th and 1st ports of the nine-way water valve constitute a coolant circuit for motor waste heat recovery; the heater core, the first plate heat exchanger, the first electronic water pump and the 8th and 9th ports of the nine-way water valve constitute a coolant circuit for passenger compartment heating; If the defrost mode is started, the first electronic expansion valve, the third electronic expansion valve and the fourth electronic expansion valve are opened, and the electric compressor, the first plate heat exchanger, the first electronic expansion valve, the outdoor air cooler, the gas-liquid integrated separator, the third electronic expansion valve, the fourth electronic expansion valve and the second plate heat exchanger form a defrost circuit.

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