CN114905935A

CN114905935A - Pure electric vehicle thermal management system and control method thereof

Info

Publication number: CN114905935A
Application number: CN202210622677.3A
Authority: CN
Inventors: 李蒙; 徐兴; 高游游; 李勇; 廉玉波; 凌和平; 邱嵩
Original assignee: Jiangsu University
Current assignee: Jiangsu University
Priority date: 2022-06-02
Filing date: 2022-06-02
Publication date: 2022-08-16

Abstract

The invention provides a pure electric vehicle heat management system and a control method thereof, wherein the heat management system comprises a heat pump refrigerant cycle, a motor coolant cycle and a battery coolant cycle, the heat pump refrigerant cycle comprises a compressor, a condenser, a water chiller, an evaporator, a first electronic expansion valve, a second electronic expansion valve, a third electronic expansion valve, a first three-way valve, a first one-way valve, a second one-way valve and a gas-liquid separator, the motor coolant cycle comprises a first water pump, a driving motor, a second three-way valve, a third three-way valve and a radiator, and the battery coolant cycle comprises a second water pump, a power battery and a fourth three-way valve. The whole vehicle heat management system simplifies a heat dissipation module at the front end of the vehicle, realizes heat pump heating at low temperature and simultaneous and sufficient cooling of the battery, the electric drive system and the cabin at high temperature through the single radiator, and reduces heat management energy consumption at low temperature through waste heat recovery of the battery and the electric drive system.

Description

Pure electric vehicle thermal management system and control method thereof

Technical Field

The invention belongs to the technical field of new energy automobile thermal management, and particularly relates to a pure electric automobile thermal management system and a control method thereof.

Background

With the development of pure electric vehicles, the automobile industry puts higher requirements on the endurance mileage of the vehicles. Under the condition of low-temperature or high-temperature climate, the higher energy consumption of the heating, ventilating and air conditioning system becomes a technical bottleneck for restricting mileage and further improving the technology. In addition, in order to reduce the running wind resistance, the heat dissipation module at the front end of the vehicle is required to be more compact, so that a new constraint condition of thermal management design is formed. Currently, most thermal management systems achieve higher heating, ventilation and air conditioning performance coefficients through heat pump systems. However, the energy coupling between the heat pump and the battery and the electrical drive thermal management is poor in such designs, and the outdoor heat exchanger and the radiator are present at the same time and occupy considerable cabin space.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a pure electric vehicle thermal management system and a control method thereof, which simplify the design of a heat dissipation module, comprehensively manage the energy among a cabin, a battery and an electric drive system, and improve the overall vehicle thermal management efficiency in a wide temperature range.

The present invention achieves the above-described object by the following means.

A pure electric vehicle thermal management system, comprising:

a heat pump refrigerant cycle comprising a compressor, a condenser, a water chiller, an evaporator and a vapor-liquid separator; the air inlet of the compressor is sequentially connected with an air-liquid separator and a second one-way valve, and the second one-way valve is respectively communicated with the water cooler through a first one-way valve and the water condenser through a first three-way valve; the first one-way valve is also communicated with the evaporator and the second electronic expansion valve, and the first three-way valve is also communicated with an air outlet of the compressor and the condenser; the condenser is communicated with the first electronic expansion valve, and the water cooler is communicated with the third electronic expansion valve; the first electronic expansion valve, the second electronic expansion valve and the third electronic expansion valve are all communicated with a water condenser;

the motor cooling liquid circulation system comprises a first water pump, a driving motor and a radiator, wherein a cooling liquid outlet of the driving motor is communicated with the water chiller through a second three-way valve and a third three-way valve in sequence, a cooling liquid inlet of the driving motor is connected with a water outlet of the first water pump, and a cooling liquid inlet and a cooling liquid outlet of the driving motor are connected through a one-way valve; the second three-way valve and the third three-way valve are both communicated with an outlet of a radiator, and an inlet of the radiator is communicated with the water condenser; a cooling liquid outlet of the driving motor is communicated with the water condenser;

the battery cooling liquid circulation comprises a second water pump and a power battery which are communicated, a water inlet of the second water pump is communicated with a third three-way valve, a cooling liquid outlet of the power battery is communicated with an inlet of the radiator through a fourth three-way valve, and the fourth three-way valve is also communicated with the water chiller; and the cooling liquid outlet of the power battery is also respectively communicated with the second three-way valve and the water inlet of the first water pump.

Above-mentioned technical scheme still includes:

the fan provides required air flow for heat exchange between the cooling liquid of the radiator and air;

and the air blower is used for providing air flow required for heat exchange between the refrigerant of the condenser and the refrigerant of the evaporator and air.

Above-mentioned technical scheme still includes:

and the output interface of the control module is in communication connection with the compressor, the first electronic expansion valve, the second electronic expansion valve, the third electronic expansion valve, the first three-way valve, the first water pump, the one-way valve, the second three-way valve, the third three-way valve, the fourth three-way valve, the second water pump, the fan and the blower respectively.

A control method of a pure electric vehicle thermal management system comprises the following steps:

the control module controls the flow of the refrigerant by controlling the compressor and controls the flow of the cooling liquid by controlling the first water pump and the second water pump, the air flow is controlled by controlling the fan and the blower, the connection and disconnection of the fluid are controlled or the appointed flowing state is realized by controlling the first electronic expansion valve, the second electronic expansion valve, the third electronic expansion valve, the first three-way valve, the one-way valve, the second three-way valve, the third three-way valve and the fourth three-way valve, therefore, the heat pump heating cabin of the whole vehicle heat management system in a low-temperature environment, the heating cabin of the heat pump by using the waste heat of the motor in the low-temperature environment, the heating cabin of the heat pump by using the waste heat of the battery in the low-temperature environment, the heating battery by using the waste heat of the motor, the cooling of the motor and the battery in a medium-temperature environment, and the cooling cabin of the heat pump air conditioner, the cooling of the motor radiator and the cooling of the battery water cooler in the high-temperature environment are realized.

Further, the heat pump heating cabin in the low-temperature environment is realized by controlling the first electronic expansion valve and the one-way valve to be opened through the control module, closing the second electronic expansion valve, the third three-way valve and the fourth three-way valve, controlling the second port and the third port of the first three-way valve to be communicated, controlling the first port and the third port of the second three-way valve to be communicated, and controlling the refrigerant flow of the compressor, the air flow of the fan and the blower, and the cooling liquid flow of the first water pump.

Further, the heat pump heats the cabin by using the waste heat of the motor in the low-temperature environment, and the first electronic expansion valve and the third electronic expansion valve are controlled to be opened by the control module, the second electronic expansion valve, the one-way valve and the first three-way valve are closed, the first port and the second port of the second three-way valve are controlled to be communicated, the second port and the third port of the third three-way valve are controlled to be communicated, the first port and the third port of the fourth three-way valve are controlled to be communicated, and the refrigerant flow of the compressor, the cooling liquid flow of the first water pump and the air flow of the blower are controlled.

Further, the heat pump heats the cabin by using the waste heat of the battery in the low-temperature environment by controlling the first electronic expansion valve and the third electronic expansion valve to be opened through the control module, controlling the first port and the third port of the third three-way valve to be communicated by closing the second electronic expansion valve, the first three-way valve, the one-way valve and the second three-way valve, and controlling the refrigerant flow of the compressor, the coolant flow of the second water pump and the air flow of the blower to be communicated by controlling the first port and the third port of the third three-way valve to be communicated.

Furthermore, the motor waste heat heating battery is realized by controlling the first electronic expansion valve, the second electronic expansion valve, the third electronic expansion valve, the one-way valve, the first three-way valve and the fourth three-way valve to be closed through the control module, controlling the first port and the second port of the second three-way valve to be communicated, controlling the first port and the second port of the third three-way valve to be communicated, and controlling the flow rates of the cooling liquids of the first water pump and the second water pump.

Further, the motor and the battery are cooled simultaneously in the medium-temperature environment by controlling the first electronic expansion valve, the second electronic expansion valve, the third electronic expansion valve, the first three-way valve, the second three-way valve, the one-way valve and the fourth three-way valve to be closed through the control module, controlling the first port and the second port of the third three-way valve to be communicated, and controlling the flow rates of the cooling liquid of the first water pump and the second water pump and the air flow rate of the fan.

Further, the cooling of the heat pump air conditioner cabin, the cooling of the motor radiator and the cooling of the battery water cooler in the high-temperature environment are realized by controlling the first electronic expansion valve and the one-way valve to be closed through the control module, controlling the second electronic expansion valve and the third electronic expansion valve to be opened, controlling the first port and the second port of the first three-way valve to be communicated, controlling the first port and the third port of the second three-way valve to be communicated, controlling the first port and the third port of the third three-way valve to be communicated, controlling the first port and the third port of the fourth three-way valve to be communicated, and controlling the refrigerant flow of the compressor, the cooling liquid flow of the first water pump and the second water pump, and the air flow of the fan and the air blower.

The beneficial effects of the invention are as follows: the heat pump refrigerant circulation, the motor coolant circulation and the battery coolant circulation of the finished automobile heat management system are respectively connected with a compressor, a condenser, a water cooler, an evaporator and a gas-liquid separator, the motor coolant circulation comprises a first water pump, a driving motor and a radiator, and the battery coolant circulation comprises a second water pump and a power battery which are communicated; the whole vehicle heat management system can realize that the heat pump heats the cabin in a low-temperature environment, the heat pump heats the cabin by utilizing the waste heat of the motor in the low-temperature environment, the heat pump heats the cabin by utilizing the waste heat of the battery in the low-temperature environment, the motor and the battery are simultaneously cooled in a medium-temperature environment, and the heat pump air conditioner cools the cabin, the motor radiator cools and the battery water cooler cools in a high-temperature environment, so that various heat management requirements in all weather conditions are met, and the energy consumption is reduced by reasonable waste heat utilization; the heat pump heating cabin in the low-temperature environment utilizes the circulation of a heat pump refrigerant to provide heating, so that the energy consumption of the heat management system is reduced; the heat pump heats the cabin by utilizing the waste heat of the motor in the low-temperature environment, so that the problem of frosting of a radiator under the continuous work of the heat pump is avoided; the efficient operation of the heat pump system is ensured through the recovery of the waste heat of the motor, and the heat pump heats the cabin by utilizing the waste heat of the battery in a low-temperature environment; the battery is heated by the waste heat of the motor, so that the problems of the rise of the internal resistance of the battery, the serious aging and the like at low temperature are solved; the motor and the battery are cooled at the same time in the medium-temperature environment, so that the heat management safety of the motor and the battery in the medium-temperature environment is ensured, and the effect of reducing the heat management energy consumption is achieved; the cooling cabin of the heat pump air conditioner in the high-temperature environment, the cooling of the motor radiator and the cooling of the battery water chiller ensure the comfort of the cabin and the heat management safety of the motor and the battery at the high temperature, and the battery water chiller solves the problem that the cooling of the battery radiator is insufficient at the high temperature.

Drawings

FIG. 1 is a diagram of a thermal management system of a pure electric vehicle according to the present invention;

FIG. 2 is a schematic view of the communication connection between the control module and each actuator of the vehicle thermal management system according to the present invention;

FIG. 3 is a schematic internal block diagram of the control module of the present invention;

FIG. 4 is a system diagram of the entire vehicle thermal management system in a cabin heating mode by a heat pump in a low temperature environment according to the present invention;

FIG. 5 is a system diagram of the entire vehicle heat management system in a low temperature environment with a heat pump utilizing motor waste heat to heat a cabin and a motor waste heat recovery mode;

FIG. 6 is a system diagram of the entire vehicle thermal management system in a low temperature environment with a heat pump utilizing battery waste heat to heat the cabin and a battery waste heat recovery mode;

FIG. 7 is a system diagram of the vehicle thermal management system in a mode of heating the battery by waste heat of the motor according to the present invention;

FIG. 8 is a system diagram of the vehicle thermal management system in a cooling mode of the motor and the battery radiator in a medium temperature environment;

FIG. 9 is a system diagram of the vehicle thermal management system in a heat pump air conditioner cooling cabin, motor radiator cooling and battery water chiller cooling mode in a high temperature environment;

in the figure: 100-whole vehicle thermal management system, 101-compressor, 102-condenser, 103-first electronic expansion valve, 104-second electronic expansion valve, 105-evaporator, 106-third electronic expansion valve, 107-water chiller, 108-first three-way valve, 109-water condenser, 110-gas-liquid separator, 201-first water pump, 202-driving motor, 203-one-way valve, 204-second three-way valve, 205-third three-way valve, 206-fourth three-way valve, 301-second water pump, 302-power battery, 401-radiator, 501-first one-way valve, 502-second one-way valve, 601-fan, 602-blower, 1011-compressor exhaust, 1012-compressor inlet, 1021-condenser first port, 1022-condenser second port, 1031-first electronic expansion valve first port, 1032-first electronic expansion valve second port, 1041-second electronic expansion valve first port, 1042-second electronic expansion valve second port, 1051-evaporator first port, 1052-evaporator second port, 1061-third electronic expansion valve first port, 1062-third electronic expansion valve second port, 1071-chiller first port, 1072-chiller second port, 1073-chiller third port, 1074-chiller fourth port, 1081-first three-way valve first port, 1082-first three-way valve second port, 1083-first three-way valve third port, 1091-water condenser first port, 1092-water condenser second port, 1093-water condenser third port, 1094-a fourth port of a water condenser, 1101-an outlet of a gas-liquid separator, 1102-an inlet of the gas-liquid separator, 2011-a water outlet of a first water pump, 2012-a water inlet of the first water pump, 2021-an outlet of a cooling liquid of a driving motor, 2022-an inlet of a cooling liquid of a driving motor, 2031-a first port of a one-way valve, 2032-a second port of a one-way valve, 2041-a first port of a second three-way valve, 2042-a second port of a second three-way valve, 2043-a third port of a second three-way valve, 2051-a first port of a third three-way valve, 2053-a third port of a third three-way valve, 2061-a first port of a fourth three-way valve, 2063-a third port of a fourth three-way valve, 3011-a water outlet of a second water pump, 3012-a water inlet of a second water pump, 3021-Power cell Coolant outlet, 3022-Power cell Coolant inlet, 4011-radiator outlet, 4012-radiator inlet, 5011-first check valve first port, 5012-first check valve second port, 5021-second check valve first port, 5022-second check valve second port, 1091-Water condenser first port, 1092-Water condenser second port, 6000-control Module, 6001-bus, 6002-input interface, 6003-memory, 6004-processor, 6005-output interface, 6101-output interface A, 6102-output interface B, 6103-output interface C, 6104-output interface D, 6105-output interface E, 6106-output interface F, 6107-output interface G, 6108-output interface H, 6109-output interface I, 6110-output interface J, 6111-output interface K, 6112-output interface L, 6113-output interface M, 6200-connection.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. For example, the electronic expansion valve and the one-way valve may be replaced by other reasonable valve types. Rather, these embodiments are provided so that this disclosure will be thorough and complete. Various embodiments of the present invention will now be described with reference to the accompanying drawings, which form a part hereof. It is to be understood that ordinal terms such as "first", "second", etc., used herein are used merely for distinction and identification, and do not have any other meanings, unless otherwise specified, and do not denote any particular order or importance. For example, the term "first three-way valve" does not itself imply the presence of "second three-way valve", nor does the term "third electronic expansion valve" itself imply the presence of "first electronic expansion valve".

Fig. 1 is a system diagram of a vehicle thermal management system 100 according to an embodiment of the present application, so as to illustrate various components and their connections in the vehicle thermal management system 100. As shown in fig. 1, the vehicle thermal management system 100 includes a compressor 101, a condenser 102, a first electronic expansion valve 103, a second electronic expansion valve 104, an evaporator 105, a third electronic expansion valve 106, a water chiller 107, a first three-way valve 108, a water condenser 109, a gas-liquid separator 110, a first water pump 201, a driving motor 202, a one-way valve 203, a second three-way valve 204, a third three-way valve 205, a fourth three-way valve 206, a second water pump 301, a power battery 302, a radiator 401, a first one-way valve 501, a second one-way valve 502, a fan 601, a blower 602, and connecting lines between the respective components indicated by connecting lines. The compressor 101, the condenser 102, the water condenser 109, the water chiller 107, the evaporator 105, the first electronic expansion valve 103, the second electronic expansion valve 104, the third electronic expansion valve 106, the first three-way valve 108, the first one-way valve 501, the second one-way valve 502, and the gas-liquid separator 110 constitute a heat pump refrigerant cycle, the first water pump 201, the driving motor 202, the one-way valve 203, the second three-way valve 204, the third three-way valve 205, and the radiator 401 constitute a motor coolant cycle, and the second water pump 301, the power battery 302, and the fourth three-way valve 206 constitute a battery coolant cycle.

The selection and operation of the various components of the overall vehicle thermal management system 100 are described below. The compressor 101 is a scroll or other electric compressor, which is used to compress refrigerant into superheated vapor and drive the refrigerant to flow in the refrigerant circulation system. The water pumps used in the first water pump 201 and the second water pump 301 are electric water pumps, and push the coolant to flow in the coolant circulation system. The water chiller 107 and the water condenser 109 are water-side heat exchangers, and provide heat exchange between the cooling liquid and the refrigerant, and specifically, the water chiller 107 cools the cooling liquid. Wherein the condenser 102 and the evaporator 105 are air side heat exchangers providing heat exchange between the air and the refrigerant. Among them, the radiator 401 is an air-side heat exchanger providing heat exchange between air and the coolant. The one-way valve 203 may be a solenoid valve type one-way valve or an electric one-way valve, and controls the opening and closing of the valve. The first electronic expansion valve 103, the second electronic expansion valve 104, and the third electronic expansion valve 106 may be electromagnetic expansion valves or electric expansion valves, and the opening degree of the valve hole is controlled to achieve the temperature accuracy of the degree of superheat or the degree of supercooling. Wherein the first one-way valve 501 and the second one-way valve 502 may be straight-through type or other types of one-way valves. The fan 601 may be a different type of fan, and provides a required air flow for heat exchange between the cooling liquid of the radiator 401 and the air. Wherein the blower 602 may be a different type of electrically powered blower that provides the required air flow for the condenser 102 and evaporator 105 refrigerant to heat exchange with the air. Wherein the gas-liquid separator 110 separates liquid refrigerant and gaseous refrigerant in the refrigerant cycle. The first three-way valve 108, the second three-way valve 204, the third three-way valve 205 and the fourth three-way valve 206 may be solenoid valves, or may be configured as other types of valves, and may be replaced reasonably as long as they conform to a specific communication manner. The first three-way valve 108 communicates only the first three-way valve second port 1082 and the first three-way valve third port 1083, and only the first three-way valve first port 1081 and the first three-way valve second port 1082. The second three-way valve 204 communicates only with the second three-way valve first port 2041 and the second three-way valve third port 2043, and communicates only with the second three-way valve first port 2041 and the second three-way valve second port 2042. The third three-way valve 205 communicates only the third three-way valve second port 2052 with the third three-way valve first port 2051 and communicates only the third three-way valve first port 2051 with the third three-way valve third port 2053. The first three-way valve 108, the second three-way valve 204, the third three-way valve 205, the fourth three-way valve 206 and the one-way valve 203 are used for controlling connection and disconnection of adjacent parts of valve ports of the valves, and therefore the purpose of controlling the thermal management operation mode is achieved.

The connecting lines between the various components of the overall vehicle thermal management system 100 are described below. The compressor inlet 1012 is communicated with the gas-liquid separator outlet 1101, and the gas-liquid separator inlet 1102 is communicated with the second check valve first port 5021; the pipeline node a is in communication with the compressor exhaust 1011, the first three-way valve first port 1081 and the condenser second port 1022, respectively; the condenser first port 1021 is in communication with a first electronic expansion valve second port 1032; the pipeline node B is respectively communicated with a first port 1031 of the first electronic expansion valve, a first port 1091 of the water condenser and a pipeline node C; the pipe node C is respectively communicated with the pipe node B, the second port 1042 of the second electronic expansion valve and the second port 1062 of the third electronic expansion valve; the evaporator second port 1052 is in communication with the second electronic expansion valve first port 1041; the pipeline node D is in communication with the first check valve first port 5011, the pipeline node E, and the evaporator first port 1051, respectively; the first port 1061 of the third electronic expansion valve is communicated with the second port 1072 of the water cooler; the first check valve second port 5012 is communicated with the water chiller first port 1071; the pipeline node E is respectively communicated with the pipeline node D, the second one-way valve second port 5022 and the first three-way valve third port 1083; the water condenser second port 1092 is in communication with a first three-way valve second port 1082; the pipeline node F is respectively communicated with the first water pump water outlet 2011, the second port 2032 of the one-way valve and the cooling liquid inlet 2022 of the driving motor; the pipeline node G is respectively communicated with the driving motor cooling liquid outlet 2021, the pipeline node H and the first port 2031 of the one-way valve; the pipeline node H is respectively communicated with the pipeline node G, the second port 2042 of the second three-way valve and the fourth port 1094 of the water condenser; the pipeline node I is respectively communicated with a radiator outlet 4011, a second port 2052 of the third three-way valve and a first port 2041 of the second three-way valve; the pipe joint J is respectively communicated with a third port 1093 of the water condenser, an inlet 4012 of the radiator and a second port 2062 of the fourth three-way valve; the pipeline node K is respectively communicated with a third port 2063 of the fourth three-way valve, a pipeline node L and a cooling liquid outlet 3021 of the power battery; the pipeline node L is respectively communicated with the pipeline node K, a third port 2043 of the second three-way valve and a water inlet 2012 of the first water pump; the first port 2061 of the fourth three-way valve is communicated with the fourth port 1074 of the water cooler; the third three-way valve third port 2053 is communicated with the water chiller third port 1073; the first port 2051 of the third three-way valve is communicated with the water inlet 3012 of the second water pump; and the power battery cooling liquid inlet port 3022 is communicated with the second water pump water outlet 3011.

FIG. 2 is a schematic diagram of communication connection between each actuator and a control module of the vehicle thermal management system. As shown in fig. 2, the control module 6000 determines the operating status of various actuators of the vehicle thermal management system 100. An output interface a6101, an output interface B6102, an output interface C6103, an output interface D6104, an output interface E6105, an output interface F6106, an output interface G6107, an output interface H6108, an output interface I6109, an output interface J6110, an output interface K6111, an output interface L6112 and an output interface M6113 of the control module are respectively in communication connection with the compressor 101, the first electronic expansion valve 103, the second electronic expansion valve 104, the third electronic expansion valve 106, the first three-way valve 108, the first water pump 201, the one-way valve 203, the second three-way valve 204, the third three-way valve 205, the fourth three-way valve 206, the second water pump 301, the fan 601 and the blower 602. The control module 6000 controls the flow of the refrigerant in the compressor 101, the control module 6000 controls the flow of the cooling liquid by controlling the first water pump 201 and the second water pump 301, the control module 6000 controls the flow of the air by controlling the fan 601 and the blower 602, and the control module 6000 controls the communication, disconnection or realization of a specified flow state of the fluid by controlling the first electronic expansion valve 103, the second electronic expansion valve 104, the third electronic expansion valve 106, the single-way valve 203, the first three-way valve 108, the second three-way valve 204, the third three-way valve 205 and the fourth three-way valve 206.

Fig. 3 is a schematic internal structural diagram of the control module 6000. As shown in fig. 3, the control module 6000 of the overall thermal management system 100 includes a bus 6001, an input interface 6002, a memory 6003, a processor 6004, and an output interface 6005. Specifically, memory 6003 is used to store programs, instructions, and data, while process 6004 reads programs, instructions, and data from memory 6003 and can write data to memory 6003. Processor 6004 effects handshaking through input interface 6002 and output interface 6005 by executing programs and instructions read from memory 6003. As shown in fig. 3, the input interface 6002 of the control module 6000 receives an operation request and other operation parameters of the vehicle thermal management system 100 through connection 6200, and each output interface is in communication connection with the compressor 101, the first electronic expansion valve 103, the second electronic expansion valve 104, the third electronic expansion valve 106, the first three-way valve 108, the first water pump 201, the one-way valve 203, the second three-way valve 204, the third three-way valve 205, the fourth three-way valve 206, the second water pump 301, the fan 601, and the blower 602. The processor 6004 controls operation of the vehicle thermal management system 100 through programs and instructions in the actuators 6003. Specifically, the control device 6000 can receive a signal for controlling an operation request or other components of the vehicle thermal management system 100 through the input interface 6002 and send a control signal to each controlled component through the output interface 6005, so that the vehicle thermal management system 100 can operate in a specified operation mode and can switch between different modes.

Fig. 4-9 are system diagrams of the overall vehicle thermal management system 100 illustrating fluid flow conditions for operation of the overall vehicle thermal management system 100 in different operating modes, wherein the hollow line arrows indicate refrigerant flow and flow paths, the bold solid line arrows indicate coolant flow and flow paths, and the other solid lines indicate no fluid flow. The various modes of operation shown in fig. 4-9 are described in detail below.

Fig. 4 is a system diagram of the entire vehicle thermal management system 100 in a mode of heating the cabin by the heat pump in a low-temperature environment. In low temperature environments, the entire vehicle thermal management system 100 may transfer heat to the cabin via a heat pump heating mode upon receiving a cabin heating command (or the control module 6000 automatically generates a cabin heating command). As shown in fig. 4, the high-temperature and high-pressure refrigerant flowing out of the compressor discharge port 1011 flows into the second port 1022 of the condenser through the pipe joint a, and the refrigerant changes from a gaseous state to a liquid state by condensation of the condenser. After the liquid high-pressure refrigerant flows out from the first port 1021 of the condenser and is decompressed and increased in volume by the first electronic expansion valve 103, a low-temperature and low-pressure liquid-mist mixture is formed and flows to the first port 1091 of the water condenser through the pipe node B, and at the moment, the cooling liquid pumped out from the first water pump outlet 2011 flows into the fourth port 1094 of the water condenser after sequentially flowing through the one-way valve 203, the pipe node G and the pipe node H. The refrigerant absorbs heat of the coolant in the water condenser 109, flows out of the water condenser second port 1092, sequentially passes through the first three-way valve second port 1082, the first three-way valve third port 1083, the pipe node E, and the second one-way valve 502, reaches the gas-liquid separator inlet 1102, and is separated from the gaseous refrigerant by the gas-liquid separator 110. The compressor inlet port 1012 sucks the gaseous refrigerant from the outlet 1101 of the gas-liquid separator, and starts the operation of the next refrigerant cycle. The second check valve 502 can effectively prevent the lubricating oil in the refrigerant from normally returning to the gas-liquid separator 110 due to the return of the refrigerant to the water condenser 109. The coolant flows out from the third port 1093 of the water condenser, flows into the radiator 401 through the pipe joint J, absorbs heat from the environment, sequentially flows through the pipe joint I, the first port 2041 of the second three-way valve, the third port 2043 of the second three-way valve and the pipe joint L, and then flows back to the first water pump inlet 2012 to complete the coolant circulation. Specifically, the first electronic expansion valve 103 and the one-way valve 203 are opened, the second electronic expansion valve 104, the third electronic expansion valve 106, the third three-way valve 205 and the fourth three-way valve 206 are all closed, the second port 1082 of the first three-way valve is communicated with the third port 1083 of the first three-way valve, the first port 2041 of the second three-way valve is communicated with the third port 2043 of the second three-way valve, and the control module 6000 controls the refrigerant flow of the compressor 101, the air flow of the fan 601 and the blower 602, and the coolant flow of the first water pump 201, so that the heat pump cabin heating mode in the low-temperature environment is realized.

Fig. 5 is a system diagram of the entire vehicle thermal management system 100 in a low-temperature environment, in which the heat pump heats the cabin by using the waste heat of the motor. When the temperature of the cooling liquid at the outlet 2021 of the driving motor is high, the waste heat of the motor can be used to heat the cabin, as shown in fig. 5, the high-temperature and high-pressure refrigerant flowing out from the exhaust 1011 of the compressor flows into the second port 1022 of the condenser through the pipe node a, and the refrigerant changes from gas state to liquid state under the condensation effect of the condenser. At this time, the first electronic expansion valve 103 is fully opened, the liquid high-pressure refrigerant flows out from the first port 1021 of the condenser, passes through the fully opened first electronic expansion valve 103, then sequentially passes through the pipe node B and the pipe node C, then passes through the partially opened third electronic expansion valve 106, and after the pressure reduction and volume increase effects, a low-temperature and low-pressure liquid mist-like mixture is formed, and flows into the second port 1072 of the water chiller, the refrigerant absorbs heat from the cooling liquid in the water chiller 107, then flows out from the first port 1071 of the water chiller, sequentially passes through the first check valve 501, the pipe node D, the pipe node E, and the second check valve 502, then flows into the inlet 1102 of the gas-liquid separator, and the liquid refrigerant and the gas refrigerant are separated by the gas-liquid separator 110. The compressor inlet port 1012 sucks the gaseous refrigerant from the outlet 1101 of the gas-liquid separator, and starts the operation of the next refrigerant cycle. On the other hand, the coolant discharged from the first water pump outlet 2011 sequentially passes through the pipe node F, the driving motor 202, the pipe node G, the pipe node H, the second three-way valve second port 2042 and the second three-way valve first port 2041, the pipe node I, the third three-way valve second port 2052 and the third three-way valve third port 2053 flow into the water cooler third port 1073, the heat released by the high-temperature coolant is absorbed by the refrigerant, the coolant flows out of the water cooler fourth port 1074 and sequentially passes through the fourth three-way valve first port 2061 and the fourth three-way valve third port 2063, the pipe node K and the pipe node L and then flows into the first water pump inlet 2012, and the motor waste heat recovery coolant circulation is formed. Specifically, the first electronic expansion valve 103 and the third electronic expansion valve 106 are opened, the second electronic expansion valve 104, the one-way valve 203 and the first three-way valve 108 are closed, the first port 2041 of the second three-way valve is communicated with the second port 2042 of the second three-way valve, the second port 2052 of the third three-way valve is communicated with the third port 2053 of the third three-way valve, the first port 2061 of the fourth three-way valve is communicated with the third port 2063 of the fourth three-way valve, and the control module 6000 controls the refrigerant flow of the compressor 101, the coolant flow of the first water pump 201 and the air flow of the blower 602, so that the heat pump can heat the cabin by using the waste heat of the motor in the low-temperature environment.

Fig. 6 is a system diagram of the entire vehicle thermal management system 100 in a low-temperature environment, in which the heat pump heats the cabin by using the waste heat of the battery. When the temperature of the coolant at the power battery outlet port 3021 is high, the working mode can replace the motor waste heat utilization with the battery waste heat utilization. Since the refrigerant cycle is identical to that of fig. 5, it will not be described herein. The difference is that the cooling liquid pumped out from the water outlet 3011 of the second water pump flows through the power battery 302 and forms high-temperature cooling liquid at the power battery outlet 3021, and then enters the fourth port 1074 of the water chiller after sequentially passing through the pipeline node K, the third port 2063 of the fourth three-way valve and the first port 2061 of the fourth three-way valve. The heat released by the high-temperature coolant is absorbed by the refrigerant, flows out of the third port 1073 of the water cooler, flows into the water inlet 3012 of the second water pump after passing through the third port 2053 of the third three-way valve and the first port 2051 of the third three-way valve, and thus, the circulation of the battery waste heat recovery coolant is formed. Specifically, the first electronic expansion valve 103 and the third electronic expansion valve 106 are opened, the second electronic expansion valve 104, the first three-way valve 108, the one-way valve 203 and the second three-way valve 204 are all closed, the first port 2051 of the third three-way valve is communicated with the third port 2053 of the third three-way valve, the first port 2061 of the fourth three-way valve is communicated with the third port 2063 of the fourth three-way valve, and the control module 6000 controls the refrigerant flow of the compressor 101, the coolant flow of the second water pump 201 and the air flow of the blower 602, so that the heat pump heats the cabin by using the waste heat of the battery in the low-temperature environment.

Fig. 7 is a system diagram of the entire vehicle thermal management system 100 in the mode of heating the battery by waste heat of the motor. In the low temperature cold start state, the motor 202 can be operated with low efficiency to rapidly increase the temperature of the cooling liquid at the driving motor cooling liquid outlet 2021, thereby heating the battery using the motor. In this mode, the coolant pumped out from the first water pump water outlet 2011 sequentially passes through the pipeline node F and the driving motor 202, and forms a high-temperature coolant at the driving motor coolant outlet 2021, and then flows into the second water pump water inlet 3012 after passing through the pipeline node G, the pipeline node H, the second three-way valve second port 2042, the second three-way valve first port 2041, the pipeline node I, the third three-way valve second port 2052, and the third three-way valve first port 2051, and the high-temperature coolant flows out from the second water pump outlet 3011 and enters the power battery coolant inlet 3022, and the high-temperature coolant heats the battery and forms a low-temperature coolant at the power battery coolant outlet 3021, and then flows into the first water pump water inlet 2012 after sequentially passing through the pipeline node K and the pipeline node L, so as to form a coolant circulation for heating the battery by the residual heat of the motor. Specifically, the first electronic expansion valve 103, the second electronic expansion valve 104, the third electronic expansion valve 106, the one-way valve 203, the first three-way valve 108 and the fourth three-way valve 206 are closed, the first port 2041 of the second three-way valve is communicated with the second port 2042 of the second three-way valve, the first port 2051 of the third three-way valve is communicated with the second port 2052 of the third three-way valve, and the control module 6000 controls the flow rates of the cooling liquids of the first water pump 201 and the second water pump 301, so that the battery heating mode by the waste heat of the motor is realized.

Fig. 8 is a system diagram of the vehicle thermal management system 100 in a motor and battery radiator cooling mode in a medium temperature environment. In a medium temperature environment, the cabin generally has no heating and cooling requirements, and the motor and the battery are cooled at the same time. This mode is applicable to ambient temperature and is fit for and battery, motor heat production are not big, dispel the heat through the radiator, can reduce the compressor load, play the effect that reduces the thermal management energy consumption. In this mode, the coolant pumped out from the second water pump outlet 3011 sequentially passes through the power battery 302, the pipeline node K, the pipeline node L, the first water pump 201, the pipeline node F, the driving motor 202, and the pipeline node G to reach the pipeline node H. Meanwhile, the coolant pumped out from the first water pump outlet 2011 sequentially passes through the pipeline node F, the driving motor 202 and the pipeline node G and then reaches the pipeline node H. The coolant collected at the pipe joint H flows into the radiator inlet 4012 after passing through the water condenser 109 and the pipe joint J in this order. Under the control of the wind speed of the fan 601, the high-temperature coolant at the radiator inlet 4012 exchanges heat with air and is cooled, low-temperature coolant is formed at the radiator outlet 4011, and then flows through the pipeline node I, the third three-way valve second port 2052 and the third three-way valve first port 2051 through the radiator outlet 4011 and flows back to the second water pump water inlet 3012, so that cooling circulation of the motor and the battery radiator in a medium-temperature environment is formed. Specifically, the first electronic expansion valve 103, the second electronic expansion valve 104, the third electronic expansion valve 106, the first three-way valve 108, the second three-way valve 204, the one-way valve 203 and the fourth three-way valve 206 are closed, the first port 2051 of the third three-way valve is communicated with the second port 2052 of the third three-way valve, and the control module controls the flow rates of the cooling liquid of the first water pump 201 and the second water pump 301 and the air flow of the fan 601, so that the cooling mode of the motor and the battery radiator in a medium-temperature environment is realized.

Fig. 9 is a system diagram of the entire vehicle thermal management system 100 in a high-temperature environment in a heat pump air-conditioning cooling cabin, a motor radiator cooling mode and a battery water cooler cooling mode. When the air temperature is high, the battery high-temperature coolant cannot exchange heat with the ambient air through the radiator, and therefore needs to be cooled through a water cooler. When the entire car thermal management system 100 receives a cabin air-conditioning refrigeration command (or the control module 6000 automatically generates the cabin refrigeration command), the refrigerant cycle refrigerates the cabin. The high-temperature and high-pressure refrigerant flowing out of the compressor discharge port 1011 passes through the pipe node a, the first three-way valve first port 1081 and the first three-way valve second port 1082 and then flows into the water condenser second port 1092, and the water condenser 109 turns the gaseous refrigerant into liquid refrigerant, and the liquid refrigerant is cooled to the environment by flowing through the radiator 401. The refrigerant flows from the water condenser first port 1091 through tube node B to tube node C. The refrigerant in one of the pipe branches flows to the second electronic expansion valve 104, forms a low-temperature and low-pressure liquid mist-like mixture under the action of the pressure reduction and volume increase of the second electronic expansion valve 104, and then flows into the evaporator second port 1052, and the refrigerant absorbs heat from the air blown out from the blower 602 at this time, reduces humidity through air refrigeration, and then flows from the evaporator first port 1051 to the pipe node D. The refrigerant in the other pipeline branch passes through the third electronic expansion valve 106, is decompressed and increased in volume and then flows into the second port 1072 of the water chiller, absorbs the heat released by the cooling liquid, flows out of the first port 1071 of the water chiller and then sequentially passes through the first check valve 501 to reach the pipeline node D. After the refrigerant is collected at the pipe node D, the refrigerant flows into the gas-liquid separator inlet 1102 after passing through the pipe node E and the second check valve 502 in sequence, and the gas-liquid separator 110 separates the liquid refrigerant from the gaseous refrigerant. The compressor inlet 1012 sucks the gaseous refrigerant from the gas-liquid separator outlet 1101, and starts the operation of the next refrigerant cycle. Different from fig. 8, in the cooling of the motor radiator in this mode, after the motor coolant flows into the pipe node I, the coolant flows through the first port 2041 of the second three-way valve, the third port 2043 of the second three-way valve, and the pipe node L, and then flows into the first water pump inlet 2012, so as to form a cooling cycle of the motor radiator. In this mode, the coolant pumped out from the second water pump water outlet 3011 sequentially flows into the water chiller fourth port 1074 after passing through the power battery 302, the pipe node K, the fourth three-way valve third port 2063 and the fourth three-way valve first port 2061, the high-temperature coolant releases a large amount of heat in the water chiller 107, then low-temperature coolant is formed at the water chiller third port 1073, and then the high-temperature coolant flows into the second water pump water inlet 3012 after passing through the third three-way valve third port 2053 and the third three-way valve first port 2051, so as to form a battery water chiller cooling cycle. Specifically, the first electronic expansion valve 103 and the one-way valve 203 are closed, the second electronic expansion valve 104 and the third electronic expansion valve 106 are opened, the first three-way valve first port 1081 is communicated with the first three-way valve second port 1082, the second three-way valve first port 2041 is communicated with the second three-way valve third port 2043, the third three-way valve first port 2051 is communicated with the third three-way valve third port 2053, the fourth three-way valve first port 2061 is communicated with the fourth three-way valve third port 2063, and the control module 6000 controls the refrigerant flow of the compressor 101, the coolant flow of the first water pump 201 and the second water pump 301, and the air flow of the fan 601 and the blower 602, so that the cooling modes of the heat pump air conditioner cabin, the motor radiator and the battery water cooler in the high-temperature environment are realized.

In this embodiment, the refrigerant flow rate of the compressor 101, the air flow rates of the fan 601 and the blower 602, and the coolant flow rates of the first water pump 201 and the second water pump 301 are determined according to the thermal management requirement, and are the prior art.

The present invention is not limited to the above-described embodiments, and any obvious improvements, substitutions or modifications can be made by those skilled in the art without departing from the spirit of the present invention.

Claims

1. A pure electric vehicles thermal management system, characterized by, includes:

a heat pump refrigerant cycle comprising a compressor (101), a condenser (102), a water condenser (109), a water chiller (107), an evaporator (105) and a gas-liquid separator (110); an air inlet of the compressor (101) is sequentially connected with an air-liquid separator (110) and a second one-way valve (502), and the second one-way valve (502) is respectively communicated with a water chiller (107) through a first one-way valve (501) and a water condenser (109) through a first three-way valve (108); the first one-way valve (501) is also communicated with the evaporator (105) and the second electronic expansion valve (104), and the first three-way valve (108) is also communicated with the air outlet of the compressor (101) and the condenser (102); the condenser (102) is communicated with a first electronic expansion valve (103), and the water chiller (107) is communicated with a third electronic expansion valve (106); the first electronic expansion valve (103), the second electronic expansion valve (104) and the third electronic expansion valve (106) are all communicated with a water condenser (109);

the motor cooling liquid circulation system comprises a first water pump (201), a driving motor (202) and a radiator (401), wherein a cooling liquid outlet of the driving motor (202) is communicated with the water chiller (107) sequentially through a second three-way valve (204) and a third three-way valve (205), a cooling liquid inlet of the driving motor (202) is connected with a water outlet of the first water pump (201), and a cooling liquid inlet and a cooling liquid outlet of the driving motor (202) are connected through a one-way valve (203); the second three-way valve (204) and the third three-way valve (205) are both communicated with an outlet of a radiator (401), and an inlet of the radiator (401) is communicated with the water condenser (109); a cooling liquid outlet of the driving motor (202) is communicated with the water condenser (109);

a battery coolant circulation system comprises a second water pump (301) and a power battery (302) which are communicated, wherein the water inlet of the second water pump (301) is communicated with a third three-way valve (205), the coolant outlet of the power battery (302) is communicated with the inlet of the radiator (401) through a fourth three-way valve (206), and the fourth three-way valve (206) is also communicated with the water chiller (107); and the cooling liquid outlet of the power battery (302) is also respectively communicated with the second three-way valve (204) and the water inlet of the first water pump (201).

2. The pure electric vehicle thermal management system of claim 1, further comprising:

a fan (601) for providing a required air flow for heat exchange between the cooling liquid of the radiator (401) and air;

and a blower (602) for providing a required air flow rate for heat exchange between the refrigerant of the condenser (102) and the evaporator (105) and air.

3. The pure electric vehicle thermal management system of claim 2, further comprising:

control module (6000), control module (6000)'s output interface carries out communication connection with compressor (101), first electronic expansion valve (103), second electronic expansion valve (104), third electronic expansion valve (106), first three-way valve (108), first water pump (201), one-way valve (203), second three-way valve (204), third three-way valve (205), fourth three-way valve (206), second water pump (301), fan (601) and air-blower (602) respectively.

4. A control method of a pure electric vehicle thermal management system based on any one of claims 1 to 3 is characterized in that:

the control module (6000) controls the flow of refrigerant by controlling the compressor (101), controls the flow of cooling liquid by controlling the first water pump (201) and the second water pump (301), controls the flow of air by controlling the fan (601) and the air blower (602), and controls the communication, disconnection or realization of a specified flow state of fluid by controlling the first electronic expansion valve (103), the second electronic expansion valve (104), the third electronic expansion valve (106), the first three-way valve (108), the one-way valve (203), the second three-way valve (204), the third three-way valve (205) and the fourth three-way valve (206), so that the heat pump of the whole vehicle heat management system heats the cabin in a low-temperature environment, the heat pump heats the cabin by using the waste heat of the motor in a low-temperature environment, the heat pump heats the cabin by using the waste heat of the battery in a low-temperature environment, the motor and the battery are cooled simultaneously in a medium-temperature environment, and the heat pump air conditioner cools the cabin in a high-temperature environment, Motor radiator cooling and battery water chiller cooling.

5. The control method according to claim 4, wherein the heat pump heats the cabin in the low temperature environment by controlling the first electronic expansion valve (103) and the one-way valve (203) to be opened, the second electronic expansion valve (104), the third electronic expansion valve (106), the third three-way valve (205) and the fourth three-way valve (206) to be closed by the control module (6000), the second port and the third port of the first three-way valve (108) to be communicated, the first port and the third port of the second three-way valve (204) to be communicated, and the refrigerant flow of the compressor (101), the air flow of the fan (601) and the blower (602), and the cooling liquid flow of the first water pump (201) to be communicated.

6. The control method according to claim 4, wherein the heat pump heats the cabin by using the residual heat of the motor in the low-temperature environment by controlling the first electronic expansion valve (103) and the third electronic expansion valve (106) to be opened, the second electronic expansion valve (104), the one-way valve (203) and the first three-way valve (108) to be closed, the first port and the second port of the second three-way valve (204) to be communicated, the second port and the third port of the third three-way valve (205) to be communicated, the first port and the third port of the fourth three-way valve (206) to be communicated, and the refrigerant flow of the compressor (101), the cooling liquid flow of the first water pump (201), and the air flow of the blower (602) to be communicated through the control module (6000).

7. The control method according to claim 4, wherein the heat pump heats the cabin by using the residual heat of the battery in the low-temperature environment by controlling the first electronic expansion valve (103) and the third electronic expansion valve (106) to be opened, the second electronic expansion valve (104), the first three-way valve (108), the one-way valve (203) and the second three-way valve (204) to be closed by the control module (6000), the first port and the third port of the third three-way valve (205) to be communicated, the first port and the third port of the fourth three-way valve (206) to be communicated, and the refrigerant flow of the compressor (101), the cooling liquid flow of the second water pump (301) and the air flow of the blower (602) to be communicated.

8. The control method according to claim 4, characterized in that the motor residual heat heating battery is realized by controlling a first electronic expansion valve (103), a second electronic expansion valve (104), a third electronic expansion valve (106), a one-way valve (203), a first three-way valve (108) and a fourth three-way valve (206) to be closed through a control module (6000), controlling a first port and a second port of a second three-way valve (204) to be communicated, controlling a first port and a second port of a third three-way valve (205) to be communicated, and controlling the flow rates of cooling liquid of a first water pump (201) and a second water pump (301).

9. The control method according to claim 4, wherein the motor and the battery are cooled simultaneously in the medium-temperature environment by controlling the first electronic expansion valve (103), the second electronic expansion valve (104), the third electronic expansion valve (106), the first three-way valve (108), the second three-way valve (204), the one-way valve (203) and the fourth three-way valve (206) to be closed by the control module (6000), controlling the first port and the second port of the third three-way valve (205) to be communicated, and controlling the flow rates of the cooling liquid of the first water pump (201) and the second water pump (301) and the air flow rate of the fan (601).

10. The control method according to claim 4, wherein the cabin cooling by the heat pump air conditioner, the motor radiator cooling and the battery water cooler cooling in the high temperature environment are controlled by the control module (6000) to close the first electronic expansion valve (103) and the one-way valve (203), open the second electronic expansion valve (104) and the third electronic expansion valve (106), communicate the first port and the second port of the first three-way valve (108), communicate the first port and the third port of the second three-way valve (204), communicate the first port and the third port of the third three-way valve (205), communicate the first port and the third port of the fourth three-way valve (206), and controlling the flow rate of the refrigerant of the compressor (101), the flow rates of the cooling liquids of the first water pump (201) and the second water pump (301), and the air flow rates of the fan (601) and the blower (602).