Whole vehicle thermal management system

Abstract

The utility model relates to a whole vehicle thermal management system, and belongs to the technical field of whole vehicle thermal management of electric vehicles. The thermal management system comprises a refrigerant module, a passenger compartment management module, a battery pack management module and a motor management module. The refrigerant module comprises a compressor, a water-cooled condenser, a liquid storage tank, an expansion valve and a cascade Chiller which are sequentially connected in the flowing direction of refrigerants, and the cascade Chiller is formed by overlapping two Chiller bodies and provided with a first refrigerant side, a first water side, a second refrigerant side and a second water side. And one end of the hot gas bypass branch is connected to the pressure discharge side, the other end of the hot gas bypass branch is connected to the second refrigerant side, and a two-way ball valve with the opening degree capable of being gradually adjusted in the range from closure to full opening is arranged on the hot gas bypass branch. According to the utility model, a double-temperature-level cold water source is provided through the cascade Chiller, so that the cross-level requirement of different water temperatures required when the passenger compartment and the battery pack are simultaneously refrigerated is met.

Description

Technical Field

[0001] The utility model belongs to the technical field of thermal management of electric vehicle whole vehicles, and relates to a thermal management system for the whole vehicle, in particular to a thermal management system for the whole vehicle which can provide a dual-temperature-step cold water source. Background Art

[0002] In the current context of global fossil energy consumption, increasing environmental pressure and increasingly stringent emission regulations, actively developing new energy vehicles is an important way to ensure energy security and achieve high-quality development. Electric vehicles not only achieve zero-emission driving, but also mark the trend of change in future travel modes. The performance, safety and range of electric vehicles are deeply affected by the effectiveness of their internal thermal management system, especially in the effective control of thermal management of batteries, motors and passenger compartments.

[0003] The thermal management of the whole vehicle mainly includes battery thermal management, motor thermal management and passenger compartment thermal management. For batteries, long-term operation of batteries in low temperature or low temperature environment will directly affect their online life and working stability. For motors, the motors and their electronic control systems will generate a lot of heat during operation, and they have a strong demand for heat dissipation. For the passenger compartment, the passenger compartment thermal management system is directly related to the internal temperature of the cabin, which directly determines the comfort of the passengers. In order to take into account the needs of multiple parties and meet the various requests for vehicle operation, the structural composition and control strategy of the vehicle thermal management system are very complex.

[0004] However, when the passenger compartment and the battery both need cooling, there may be a large difference in the required water temperature between the passenger compartment and the battery pack. For example, when the battery is fast charged in a low-temperature environment, it is necessary to meet the dehumidification and heating needs of the passenger compartment and the cooling needs of the battery at the same time. The existing vehicle thermal management system cooler usually only has a single coolant circuit, which cannot provide coolant at different temperatures, and cannot meet the cooling needs of the passenger compartment and the battery pack at the same time. Utility Model Content

[0005] In view of this, the purpose of the utility model is to provide a vehicle thermal management system, providing a dual-temperature cold water source to meet the cross-level requirements of differentiated water temperatures required when cooling the passenger compartment and the battery pack at the same time.

[0006] To achieve the above-mentioned purpose, the utility model provides a vehicle thermal management system, including a refrigerant module, the refrigerant module includes a compressor, a water-cooled condenser, a liquid storage tank, an expansion valve and a cascade chiller connected in sequence along the refrigerant flow path, the compression and discharge side of the compressor is connected to the inlet of the refrigerant side of the water-cooled condenser, and the outlet of the refrigerant side is connected to the liquid storage tank.

[0007] The cascade chiller is formed by stacking two chillers, and has a first refrigerant side, a first water side, a second refrigerant side and a second water side. The first refrigerant side and the second refrigerant side are connected in series, the expansion valve is connected to the first refrigerant side, and the second refrigerant side is connected to the suction side of the compressor.

[0008] Optionally, the refrigerant module also includes a hot gas bypass branch arranged between the compressor and the cascade chiller, one end of the hot gas bypass branch is connected to the compression and discharge side of the compressor, and the other end is connected to the second refrigerant side of the cascade chiller, and a two-way ball valve with gradually adjustable opening in the range of cut-off to full opening is arranged on the hot gas bypass branch.

[0009] Optionally, a first temperature and pressure sensor is provided on the pipeline connecting the discharge side of the compressor and the two-way ball valve, and a second temperature and pressure sensor is provided on the pipeline connecting the suction side of the compressor and the cascade chiller.

[0010] The vehicle thermal management system also includes a passenger compartment management module, which includes a blower, a water-cooled core and a dual-temperature-zone heating and cooling core arranged in the passenger compartment air-conditioning assembly. The water-cooled core and the dual-temperature-zone heating and cooling core are arranged on the air outlet side of the blower, and both ends of the water-cooled core are respectively connected to the two ends of the second water side of the cascade chiller. The dual-temperature-zone heating and cooling core includes a first temperature zone of the core and a second temperature zone of the core. Both ends of the first temperature zone of the core and the second temperature zone of the core are respectively connected to the two ends of the first water side of the cascade chiller.

[0011] The vehicle thermal management system also includes a battery pack management module, which includes a battery pack, and the coolant channels of the battery pack are respectively connected to the two ends of the first water side of the cascade chiller.

[0012] The vehicle thermal management system also includes a motor management module, which includes an EDU cooling unit and a low-temperature radiator. The EDU cooling unit and the low-temperature radiator are connected in series with the water side of the water-cooled condenser to form a closed loop.

[0013] Optionally, a first three-way valve is provided on the pipeline connecting the low-temperature radiator and the water-cooled condenser, and the other outlet of the first three-way valve is connected to the outlet end of the first water side of the cascade chiller; a second three-way valve is provided on the pipeline connecting the EDU cooling unit and the water-cooled condenser, and the other outlet of the second three-way valve is connected to the inlet end of the first water side of the cascade chiller.

[0014] Optionally, a third three-way valve is further provided on the pipeline connecting the first three-way valve and the cascade chiller, and another outlet of the third three-way valve is connected to the EDU cooling unit.

[0015] Optionally, a first four-way valve and a second four-way valve are respectively provided on the pipeline connecting the battery pack and the cascade chiller. The first four-way valve is provided at the inlet end of the coolant channel of the battery pack, and the second four-way valve is provided at the outlet end of the coolant channel of the battery pack. The battery pack is respectively connected to the two ends of the second water side of the cascade chiller and the two ends of the water side of the water-cooled condenser through the first four-way valve and the second four-way valve.

[0016] Optionally, a fourth three-way valve is provided on the pipeline connecting the water-cooling core and the outlet end of the second water side, and the other outlet of the fourth three-way valve is connected to the first four-way valve; an eighth three-way valve is provided on the pipeline connecting the water-cooling core and the inlet end of the second water side, and the other outlet of the eighth three-way valve is connected to the outlet end of the second water side.

[0017] Optionally, a fifth three-way valve is provided on the pipeline connecting the first temperature zone of the core and the outlet end of the first water side, and the other outlet of the fifth three-way valve is connected to the water side outlet end of the water-cooled condenser; a sixth three-way valve is provided on the pipeline connecting the second temperature zone of the core and the outlet end of the first water side, and the other outlet of the sixth three-way valve is connected to the water side outlet end of the water-cooled condenser.

[0018] Optionally, the outlet ends of the first temperature zone of the core and the second temperature zone of the core are combined into one pipeline, and a seventh three-way valve is provided on the pipeline connected to the first water side inlet end of the cascade chiller, and the other outlet of the seventh three-way valve is connected to the water side inlet end of the water-cooled condenser.

[0019] Optionally, a first water pump is provided at the inlet end of the first water side of the cascade chiller, a second water pump is provided at the inlet end of the second water side of the cascade chiller, and a third water pump is provided at the inlet end of the water side of the water-cooled condenser.

[0020] Optionally, the vehicle thermal management system provided by the present invention further includes at least one kettle, which is respectively connected to both ends of the water side of the water-cooled condenser and both ends of the first water side and the second water side of the cascade chiller.

[0021] Optionally, the vehicle thermal management system provided by the present invention also includes a first water kettle, a second water kettle and a third water kettle, the first water kettle is connected to the two ends of the water side of the water-cooled condenser, the second water kettle is connected to the two ends of the first water side of the cascade chiller, and the third water kettle is connected to the two ends of the second water side of the cascade chiller.

[0022] The beneficial effects of the utility model are:

[0023] The vehicle thermal management system provided by the utility model includes a cascade chiller, which is composed of two ordinary chillers stacked together. It adopts a circuit structure in which the first refrigerant side and the second refrigerant side are connected in series, and the first water side and the second water side are independent of each other. The cascade chiller of the utility model can provide differentiated refrigerant evaporation temperatures, and then obtain coolants of different temperatures to meet differentiated water temperature cross-temperature requirements such as passenger compartment cooling and battery pack cooling.

[0024] The utility model adds a hot gas bypass branch to the refrigerant module, and based on this provides a low-temperature activation mode and a hot gas compensation operation mode of the refrigerant module, so that the system provided by the utility model can cancel the setting of the high-energy-consuming PTC, broaden the refrigeration and heating range of the compressor under the premise of unchanged compressor speed conditions, significantly reduce system energy consumption, realize pressure-free operation in the entire temperature range, and greatly enhance system reliability, safety and cost-effectiveness of the system.

[0025] The vehicle thermal management system provided by the utility model is only equipped with one external low-temperature radiator, while the existing thermal management systems are mostly equipped with at least two external heat exchangers, which makes the overall air intake wind resistance of the existing technology larger. Therefore, under the same conditions, the wind resistance of the utility model is smaller, so that a larger air volume can be used for the radiator to dissipate heat or absorb heat, thereby making the power of the matching electronic fan relatively reduced.

[0026] The vehicle thermal management system provided by the utility model adopts a fully indirect system structure. The refrigerant does not directly enter the passenger compartment, and the heat exchange medium in the passenger compartment is coolant. In other words, the utility model indirectly manages the thermal management of the passenger compartment through the coolant after heat exchange with the refrigerant. Therefore, for new refrigerants that are flammable, have high operating pressure, and are toxic, the utility model can significantly reduce the risk of dangerous refrigerant leakage and spread to the passenger compartment due to abnormal factors, thereby improving the safety index of the driving cabin. In addition, the various circuits in the vehicle thermal management system provided by the utility model are all one-way circulation circuits, and there is no need to reverse when switching between various modes. The operation process of each circuit is stable and reliable.

[0027] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and will be apparent to those skilled in the art based on the following examination and research, or can be taught from the practice of the present invention to some extent. The objectives and other advantages of the present invention can be achieved and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be described in detail below in conjunction with the accompanying drawings, wherein:

[0029] Figure 1 A schematic diagram of the structure of the vehicle thermal management system provided by the utility model;

[0030] Figure 2 This is a schematic diagram of the structure of the refrigerant module of the vehicle thermal management system provided by the utility model;

[0031] Figure 3 A schematic diagram of the circulation of the refrigerant module of the vehicle thermal management system provided by the utility model in the normal operation mode;

[0032] Figure 4 A schematic diagram of the system cycle of the vehicle thermal management system provided by the utility model in the passenger compartment heating and dehumidification mode;

[0033] Figure 5 This is a schematic diagram of the system cycle of the vehicle thermal management system provided by the utility model in the battery pack forced cooling mode.

[0034] Reference numerals:

[0035] 1- compressor; 2- water-cooled condenser; 2.1- water side; 2.2- third water pump; 2.3- refrigerant side; 3- liquid storage tank; 4- expansion valve; 5- two-way ball valve; 6- cascade chiller; 6.1- first refrigerant side; 6.2- first water side; 6.3- first water pump; 6.4- second refrigerant side; 6.5- second water side; 6.6- second water pump; 7- blower; 8- water-cooled core; 9- dual temperature zone heating and cooling core; 9.1- first temperature zone of core; 9.2- second temperature zone of core; 10- battery pack; 11- low temperature radiator; 12- EDU cooling unit; 13- first kettle; 14 -Second kettle; 15-third kettle; 16-electronic fan; 17-first three-way valve; 18-second three-way valve; 19-third three-way valve; 20-fourth three-way valve; 21-fifth three-way valve; 22-sixth three-way valve; 23-seventh three-way valve; 24-eighth three-way valve; 25-first four-way valve; 26-second four-way valve; 27-first temperature sensor; 28-second temperature sensor; 29-third temperature sensor; 30-fourth temperature sensor; 31-fifth temperature sensor; 32-sixth temperature sensor; 33-first temperature and pressure sensor; 34-second temperature and pressure sensor; 35-concentration sensor. DETAILED DESCRIPTION

[0036] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0037] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0038] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "back" and the like indicate directions or positional relationships, they are based on the directions or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as a limitation on the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0039] The utility model provides a vehicle thermal management system, such as Figure 1 As shown, it includes a refrigerant module, a battery pack management module, a passenger compartment management module and a motor management module.

[0040] like Figure 2As shown, the refrigerant module includes a compressor 1, a water-cooled condenser 2, a liquid storage tank 3, an expansion valve 4 and a cascade Chiller 6 connected in sequence along the refrigerant flow path, the compression and discharge side of the compressor 1 is connected to the refrigerant side 2.3 inlet of the water-cooled condenser 2, and the refrigerant side 2.3 outlet of the water-cooled condenser 2 is connected to the liquid storage tank 3. The cascade Chiller 6 is composed of two Chillers stacked together, which have a first refrigerant side 6.1, a first water side 6.2, a second refrigerant side 6.4 and a second water side 6.5 arranged side by side, and the first refrigerant side 6.1 and the second refrigerant side 6.4 are connected in sequence through pipes. Because the cascade Chiller 6 is a structure formed by the superposition of two Chillers, it has an independent two-way water circuit design, which enables it to absorb the energy of a single or multiple heat sources, thereby ensuring a wider range of heating needs. The expansion valve 4 is connected to the first refrigerant side 6.1, and the second refrigerant side 6.4 is connected to the pressure and suction side of the compressor 1.

[0041] The water-cooled condenser 2 includes a refrigerant side 2.3 for the flow of refrigerant and a water side 2.1 for the flow of coolant. The high-temperature and high-pressure refrigerant flows from the compression and discharge side of the compressor 1 to the refrigerant side 2.3 of the water-cooled condenser 2, and exchanges heat with the water in the water side 2.1 of the water-cooled condenser 2. After the heat exchange, the medium-temperature and high-pressure refrigerant flows into the liquid storage tank 3 for storage. The outlet of the liquid storage tank 3 is connected to the expansion valve 4, and the medium-temperature and high-pressure refrigerant is converted into a two-phase state through the expansion valve 4. The two-phase refrigerant flows into the first refrigerant side 6.1 of the cascade Chiller 6, and then flows into the second refrigerant side 6.4. In this process, it exchanges heat with the first water side 6.2 and the second water side 6.5 to form a superheated low-temperature and low-pressure state, and then enters the compressor 1 from the pressure and suction side of the compressor 1 to increase pressure and enthalpy again for the next cycle.

[0042] The utility model specially adds a hot gas bypass branch in the refrigerant module, such as Figure 2 As shown, the hot gas bypass branch is arranged between the compression discharge side of the compressor 1 and the cascade chiller 6, one end is connected to the compression discharge side of the compressor 1, and the other end is connected to the second refrigerant side 6.4 of the cascade chiller 6, so as to introduce the refrigerant discharged from the compressor 1 into the cascade chiller 6 from the second refrigerant side 6.4. A two-way ball valve 5 is arranged on the hot gas bypass branch, and the two-way ball valve 5 is opened at an appropriate time to realize the startup and thermal compensation functions of the thermal management system in an ultra-low temperature environment. Furthermore, a first temperature and pressure sensor 33 is arranged on the pipeline connecting the compression discharge side of the compressor 1 to the hot gas bypass branch, and a second temperature and pressure sensor 34 is arranged on the pipeline connecting the suction side of the compressor 1 to the second refrigerant side 6.4 of the cascade chiller 6, so as to monitor the temperature and pressure of the refrigerant at the inlet and outlet ends of the compressor 1.

[0043] Generally speaking, the speed of the compressor 1 determines the cooling or heating capacity that the system can provide. Under normal temperature conditions, even if the compressor 1 runs at the lowest speed, the minimum cooling or heating capacity provided by the system may still be higher than the request of the demand side. At this time, the demand side is usually met by frequently starting and stopping the compressor 1, which not only reduces the user experience, but also easily damages the components of the system and reduces the service life of the system. The utility model sets a hot gas bypass branch in the refrigerant module, and directly introduces the high-temperature hot gas on the compression and discharge side of the compressor 1 into the Chiller, which can reduce the evaporation capacity of the Chiller, thereby achieving the effect of reducing the cooling capacity. At the same time, since part of the hot gas passes through the hot gas bypass branch, the refrigerant flow entering the condenser is reduced, thereby reducing the heat dissipation of the condenser. It can be seen that the hot gas bypass branch can broaden the cooling and heating range of the compressor 1 under the premise of unchanged speed conditions, and can also significantly reduce the energy consumption of the system. Furthermore, the refrigerant flow in the hot gas bypass branch is managed by the opening of the two-way ball valve 5, which can more conveniently adjust the system pressure ratio and redundancy performance.

[0044] like Figure 1 As shown, the passenger compartment management module includes a blower 7, a water-cooled core 8 and a dual-zone heating and cooling core 9 arranged in the passenger compartment air conditioning assembly, and each component is arranged in the air conditioning box HVAC assembly. The water-cooled core 8 and the dual-zone heating and cooling core 9 are arranged on the air outlet side of the blower 7, and the two ends of the water-cooled core 8 are respectively connected to the two ends of the second water side 6.5 of the cascade Chiller 6. The dual-zone heating and cooling core 9 includes a first core temperature zone 9.1 and a second core temperature zone 9.2, and the two ends of the first core temperature zone 9.1 and the second core temperature zone 9.2 are respectively connected to the two ends of the first water side 6.2 of the cascade Chiller 6. The blower 7 inhales the circulating air of the passenger compartment, and adjusts the temperature of the circulating air under the joint action of the water-cooled core 8 and the dual-zone heating and cooling core 9. The adjusted circulating air is blown into the passenger compartment again to form various thermal management states such as heating, cooling or dehumidification of the passenger compartment. The single-temperature zone or dual-temperature zone cooling function of the passenger compartment can be realized by selectively activating the first temperature zone 9.1 of the core or the second temperature zone 9.2 of the core or activating both at the same time.

[0045] Furthermore, a concentration sensor 35 is provided at the outlet of the blower 7, and a first temperature sensor 27 is provided on the connecting pipeline between the water-cooled core 8 and the second water side 6.5 of the cascade chiller 6, and the first temperature sensor 27 is provided on the outlet end of the second water side 6.5. A first water pump 6.3 is provided on the connecting pipeline between the dual-temperature zone cooling and heating core 9 and the first water side 6.2 of the cascade chiller 6, and the first water pump 6.3 is provided on the inlet end of the first water side 6.2. A second water pump 6.6 is provided on the connecting pipeline between the water-cooled core 8 and the second water side 6.5 of the cascade chiller 6, and the second water pump 6.6 is provided on the inlet end of the second water side 6.5.

[0046] The battery pack 10 management module includes a battery pack 10 , the coolant channel of the battery pack 10 is respectively connected to the two ends of the first water side 6 . 2 of the cascade Chiller 6 , and a second temperature sensor 28 is arranged on the inlet end of the coolant channel of the battery pack 10 .

[0047] The motor management module includes an EDU cooling unit 12 (EDU refers to the motor electronic control unit, hereinafter referred to as), and the motor may have a stall heating function. One end of the EDU cooling unit 12 is directly connected to the water side 2.1 inlet end of the water-cooled condenser 2, and the other end is connected to the water side 2.1 outlet end of the water-cooled condenser 2 through the low-temperature radiator 11. An electronic fan 16 is also provided on one side of the low-temperature radiator 11, and a third temperature sensor 29 is provided near the electronic fan 16 to monitor the ambient temperature. A fourth temperature sensor 30 is provided on the connecting section between the EDU cooling unit 12 and the water-cooled condenser 2, and a third water pump 2.2 is provided at the water side 2.1 inlet end of the water-cooled condenser 2.

[0048] A first three-way valve 17 is provided on the pipeline connecting the low-temperature radiator 11 and the outlet of the water side 2.1 of the water-cooled condenser 2, and the two outlets of the first three-way valve 17 are respectively connected to the low-temperature radiator 11 and the water-cooled condenser 2, and the other outlet of the first three-way valve 17 is connected to the first water side 6.2 of the cascade chiller 6. A second three-way valve 18 is provided on the pipeline connecting the EDU cooling unit 12 and the inlet end of the water side 2.1 of the water-cooled condenser 2, and the two outlets of the second three-way valve 18 are respectively connected to the EDU cooling unit 12 and the water-cooled condenser 2, and the other outlet of the second three-way valve 18 is connected to the first water side 6.2 of the cascade chiller 6. Further, a third three-way valve 19 is also provided on the pipeline connecting the first three-way valve 17 and the cascade chiller 6, and the two outlets of the third three-way valve 19 are respectively connected to the first three-way valve 17 and the cascade chiller 6, and the other outlet of the third three-way valve 19 is connected to the EDU cooling unit 12. A fifth temperature sensor 31 is provided on the connection passage between the third three-way valve 19 and the cascade chiller 6 , and a sixth temperature sensor 32 is provided on the outlet end of the water side 2 . 1 of the water-cooled condenser 2 .

[0049] The first four-way valve 25 and the second four-way valve 26 are respectively provided on the pipeline connecting the coolant channel of the battery pack 10 and the first water side 6.2 of the cascade chiller 6. The first four-way valve 25 is provided at the coolant inlet of the battery pack 10, and the second four-way valve 26 is provided at the coolant channel outlet of the battery pack 10. Two outlets of the first four-way valve 25 are respectively connected to the battery pack 10 and the first water side 6.2 outlet of the cascade chiller 6, and the other two outlets are respectively connected to the water side 2.1 outlet of the water-cooled condenser 2 and the second water side 6.5 outlet of the cascade chiller 6. Two outlets of the second four-way valve 26 are respectively connected to the coolant channel of the battery pack 10 and the first water side 6.2 inlet of the cascade chiller 6, and the other two outlets are respectively connected to the water side 2.1 inlet of the water-cooled condenser 2 and the second water side 6.5 inlet of the cascade chiller 6. That is, the coolant channel of the battery pack 10 is connected to both ends of the first water side 6.2, both ends of the second water side 6.5 and both ends of the water side 2.1 of the water-cooled condenser 2 through the first four-way valve 25 and the second four-way valve 26 respectively.

[0050] A fourth three-way valve 20 is provided on the pipeline connecting the water-cooled core 8 and the outlet end of the second water side 6.5, and the two outlets of the fourth three-way valve 20 are respectively connected to the water-cooled core 8 and the second water side 6.5, and the other outlet is connected to the first four-way valve 25. A fifth three-way valve 21 is provided on the pipeline connecting the core first temperature zone 9.1 and the outlet end of the first water side 6.2 of the cascade chiller 6, and the two outlets of the fifth three-way valve 21 are respectively connected to the core first temperature zone 9.1 and the first water side 6.2 of the cascade chiller 6, and the other outlet is connected to the outlet end of the water side 2.1 of the water-cooled condenser 2. A sixth three-way valve 22 is provided on the pipeline connecting the core second temperature zone 9.2 and the outlet end of the first water side 6.2 of the cascade chiller 6, and the two outlets of the sixth three-way valve 22 are respectively connected to the core second temperature zone 9.2 and the first water side 6.2 of the cascade chiller, and the other outlet is connected to the outlet end of the water side 2.1 of the water-cooled condenser 2. A seventh three-way valve 23 is provided on the pipeline connecting the dual-temperature zone cooling and heating core 9 and the first water side 6.2 inlet of the cascade chiller, and two outlets of the seventh three-way valve 23 are respectively connected to the dual-temperature zone cooling and heating core 9 and the first water side 6.2 of the cascade chiller 6, and the other outlet is connected to the water side 2.1 inlet of the water-cooled condenser 2. An eighth three-way valve 24 is provided on the pipeline connecting the water-cooled core 8 and the second water side 6.5 of the cascade chiller 6, and two outlets of the eighth three-way valve 24 are respectively connected to the water-cooled core 8 and the second water side 6.5 inlet, and the other outlet is connected to the second water side 6.5 outlet.

[0051] The vehicle thermal management system provided by the utility model further includes at least one kettle, which is respectively connected to both ends of the water side 2.1 of the water-cooled condenser 2, and both ends of the first water side 6.2 and the second water side 6.5 of the cascade chiller 6. In one embodiment, the vehicle thermal management system of the utility model may include a first kettle 13, a second kettle 14 and a third kettle 15, wherein the first kettle 13 is connected to both ends of the water side 2.1 of the water-cooled condenser 2, the second kettle 14 is connected to both ends of the first water side 6.2 of the cascade chiller 6, and the third kettle 15 is connected to both ends of the second water side 6.5 of the cascade chiller 6.

[0052] In some embodiments of the utility model, the first three-way valve 17, the second three-way valve 18 and the third three-way valve 19 can be integrated into a cascade water valve, the fifth three-way valve 21, the sixth three-way valve 22 and the seventh three-way valve 23 can be integrated into a cascade water valve, the first four-way valve 25 and the second four-way valve 26 can be integrated into a cascade water valve, and the fourth three-way valve 20 and the eighth three-way valve 24 can be integrated into a cascade water valve. The cascade water valve has a plurality of independently controllable rotary joints, and the opening direction of each three-way valve and each four-way valve is realized by controlling the rotation angle of each rotary joint. On the one hand, it can simplify the number of components and reduce the control difficulty, and on the other hand, it can also improve the integration and reduce the occupied space.

[0053] In some embodiments of the present invention, the refrigerant module of the present invention has multiple activation modes, including a normal operation mode, a low-temperature activation mode, and a hot gas compensation operation mode.

[0054] Figure 3 The schematic diagram of the circulation of the refrigerant module of the vehicle thermal management system provided by the utility model in the normal operation mode, in which the two-way ball valve 5 is closed, and the other functional parts of the refrigerant module, the compressor 1 and the expansion valve 4, are opened. In this process, the pressure-suction side of the compressor 1 inhales the low-temperature and low-pressure gaseous refrigerant, which becomes a high-temperature and high-pressure gaseous refrigerant after being pressurized and enthalpy-increased by the compressor 1. The refrigerant in this state flows into the refrigerant side 2.3 of the water-cooled condenser 2, and after heat exchange with the water side 2.1, it becomes a medium-temperature and high-pressure supercooled liquid refrigerant and flows into the liquid storage tank 3, and then expands through the expansion valve 4 to become a two-phase refrigerant, and flows into the cascade Chiller 6 through the inlet of the first refrigerant side 6.1. The refrigerant absorbs the heat of the coolant on the first water side 6.2, so that the temperature of the coolant is reduced to a fluid with cold capacity, and the refrigerant on the first refrigerant side 6.1 absorbs heat to become a refrigerant with a certain degree of superheat, and then flows into the interior of the compressor 1 through the pressure-suction side. During this process, the two-way ball valve 5 is in a closed state, and the speed of the compressor and the opening of the expansion valve 4 are adjusted according to various heat load requirements.

[0055] In a low-temperature environment, the low-temperature activation mode of the refrigerant circuit is started according to the data logic judgment collected by the third temperature sensor 29, i.e., the ambient temperature sensor and the temperature-stabilizing pressure sensor of the refrigerant module. Specifically, when the ambient temperature detected by the third temperature sensor 29 is lower than the minimum startup temperature, and the first temperature-pressure sensor 33 measures the refrigerant pressure from the compression and discharge side of the compressor 1 < P1 (P1 is the minimum allowable pressure value for opening the two-way ball valve 5 in the low-temperature activation mode of the refrigerant module), the refrigerant module adopts the low-temperature activation mode. First, turn off the first water pump 6.3 and the second water pump 6.6 of the cascade Chiller 6, the third water pump 2.2 and the electronic fan 16 of the water-cooled condenser 2, and then turn off the two-way ball valve 5 and the expansion valve 4, and then start the compressor 1 at a low speed. Then open the two-way ball valve 5 to allow the hot air flow to flow into the second refrigerant side 6.4 of the cascade Chiller 6, and then flow back to the compression and discharge side of the compressor 1. The refrigerant continues to circulate between "compressor 1-second refrigerant side 6.4-compressor 1" to adjust the pressure and temperature of the refrigerant sucked into the suction side, avoiding the need to set a PTC electric auxiliary heating device to heat and pressurize the refrigerant, greatly reducing the system energy consumption and enhancing the reliability and safety of the system.

[0056] The speed of compressor 1 is gradually increased to ensure that the superheat of the refrigerant on the compression and discharge side of compressor 1 is within a reasonable range. The current superheat of the refrigerant can be calculated through the monitoring result of the first temperature and pressure sensor 33. After multiple cycles, the temperature and pressure of the refrigerant on the high-pressure discharge side are continuously raised until the refrigerant pressure on the compression and discharge side detected by the first temperature and pressure sensor 33 is greater than P2, and P2 is greater than P1 (P2 is the maximum allowable pressure value for opening the two-way ball valve 5 in the low-temperature activation mode of the refrigerant module). At this time, the expansion valve 4 is first opened and the two-way ball valve 5 is closed, and then the water side 2.1 water pump of the condenser, the third water pump 2.2, the first water side 6.2 and the second water side 6.5 water pumps of the cascade Chiller 6, the first water pump 6.3 and the second water pump 6.6 are opened. The duty cycles of the first water pump 6.3, the second water pump 6.6, the third water pump 2.2, the electronic fan 16 and the blower 7 are adjusted so that the monitoring results of the first temperature and pressure sensor 33 and the second temperature and pressure sensor 34 (i.e., the refrigerant superheat SH on the suction side and the refrigerant pressure P on the discharge side) meet the system requirements.

[0057] When the refrigerant pressure on the discharge side detected by the first temperature and pressure sensor 33 is ≥ P2 (P2>P1), and the superheat SH on the suction side monitored by the second temperature sensor 28 is ≥ T, the low-temperature start-up of the refrigerant module is completed and can be transferred to the normal operation mode. T is the designed superheat for reliable operation of the refrigerant module.

[0058] When the refrigerant module is transferred from the low-temperature activation mode to the normal operation mode, it is determined whether the heating demand can be downgraded or temporarily shut down. If it can be downgraded or temporarily shut down, the liquid flow of the third water pump 2.2 of the water-cooled condenser 2 is gradually reduced. If the refrigerant superheat SH on the pressure-suction side is greater than T1, it is determined that the current heating demand can be met, and T1 is the minimum superheat allowed for the refrigerant module to operate. If the flow of the water-cooled condenser 2 cannot meet SH>T1 after adjustment, that is, when the refrigerant superheat SH on the pressure-suction side is always ≤T1, T1 is the minimum superheat allowed for the refrigerant module to operate, then the condenser flow adjustment method is abandoned, and the third water pump 2.2 is adjusted to the default opening, and the hot gas compensation mode is turned on.

[0059] Alternatively, when the refrigerant module is successfully started in low-temperature activation mode and transferred to normal mode, due to factors such as low ambient temperature, the refrigerant in the cascade Chiller 6 may not absorb enough heat from the coolant, resulting in the second temperature and pressure sensor 34 detecting that the superheat SH of the refrigerant is lower than T1. If the superheat of the refrigerant on the pressure-suction side is adjusted by adjusting the opening of the expansion valve 4, the speed of the compressor 1, the flow rate of the water pump, etc., there are disadvantages of complex control strategies and unstable systems. The control results may not necessarily meet the needs of heating and dehumidification in low-temperature winter environments. At this time, the hot gas compensation operation mode needs to be turned on.

[0060] After the hot gas compensation operation mode is turned on, the third water pump 2.2 is adjusted to the default opening, the two-way ball valve 5 is opened to the default opening, and then the opening of the two-way ball valve 5 is gradually increased to guide part of the high-temperature and high-pressure gaseous refrigerant on the discharge side from the second refrigerant side 6.4 into the cascade Chiller 6, and after heat exchange with the coolant on the second water side 6.5, it flows back to the compressor 1 from the suction side. In the process of gradually increasing the opening of the two-way ball valve 5, the refrigerant superheat SH on the suction side is monitored to keep SH within the range of T1 to T2, where T2 is the maximum superheat allowed for the operation of the refrigerant module.

[0061] If the refrigerant superheat SH on the pressure-suction side is too high, the two-way ball valve 5 is gradually reduced or closed to reduce the flow in the hot gas bypass branch. If the refrigerant superheat SH on the pressure-suction side is too low, the two-way ball valve 5 is gradually opened to increase the flow in the hot gas bypass branch. If only adjusting the two-way ball valve 5 cannot control SH within the preset range, it is necessary to combine and adjust the compressor 1, water pump, electronic fan 16, blower 7 and other components to meet the functional requirements in this scenario.

[0062] The low-temperature activation mode and hot gas compensation operation mode of the refrigerant module can increase the speed of compressor 1 in a low-temperature environment, so that compressor 1 can also play a high-quality heating function in a low-temperature environment, thereby avoiding the need to set up a PTC electric heater in the system for auxiliary heating, which not only reduces production costs and makes the system layout more compact, but also greatly enhances the safety and reliability of the system. In addition, the hot gas bypass branch can also improve the suction capacity of compressor 1 in a low-temperature environment, avoid frequent start-stop or oil shortage and over-temperature of compressor 1, enhance the oil return capacity of the system, and improve the reliability and service life of system components.

[0063] In some embodiments of the utility model, in order to prevent the front windshield from fogging up and affecting driving safety, the dehumidification function needs to be turned on while the passenger compartment is heated. In this process, in addition to dehumidifying and heating the passenger compartment, it is also necessary to pay attention to whether the battery pack 10 needs to be preheated or cooled. Based on this, the heating and dehumidification mode can be classified according to the heat source of the cascade Chiller 6. The heat source of the cascade Chiller 6 includes the air heat source of the external low-temperature radiator 11, the heat source of the motor operation or stall heating, the self-heating or power output heat source of the battery pack 10, and the heat source of dehumidification in the full internal circulation mode of the passenger compartment. Single or multiple combinations of heat sources can form different operating modes.

[0064] Especially when the battery pack 10 is fast charged in a low temperature environment, it is necessary to meet the dehumidification and heating needs of the passengers in the passenger compartment while also meeting the system's request for cooling the battery pack 10. Figure 4 As shown, the passenger compartment heating and dehumidification mode uses the battery pack 10 and internal circulation dehumidification as dual heat sources.

[0065] Specifically, close all outlets of the first three-way valve 17, the second three-way valve 18, and the third three-way valve 19, close the outlet of the fourth three-way valve 20 leading to the first water side 6.2 of the cascade Chiller 6, close the outlet of the fifth three-way valve 21 leading to the first water side 6.2 of the cascade Chiller 6, close the outlet of the sixth three-way valve 22 leading to the first water side 6.2 of the cascade Chiller 6, close the outlet of the seventh three-way valve 23 leading to the first water side 6.2 of the cascade Chiller 6, close the first four-way valve 25 leading to the second water side 6.5 of the cascade Chiller 6 and the two outlets of the water-cooled condenser 2, and close the second four-way valve 26 leading to the second water side 6.5 of the cascade Chiller 6 and the two outlets of the water-cooled condenser 2.

[0066] In this mode, the refrigerant module is started, and the circuit formed is: compressor 1 discharge side - water-cooled condenser 2 refrigerant side 2.3 - liquid storage tank 3 - expansion valve 4 - first refrigerant side 6.1 of cascade Chiller 6 - second refrigerant side 6.4 of cascade Chiller 6 - suction side of compressor 1; the circuit formed by the battery pack management module is: battery pack 10 - first water side 6.2 of cascade Chiller 6 - battery pack 10; the passenger compartment management module constitutes two circuits, namely: water-cooled core 8 - second water side 6.5 of cascade Chiller - water-cooled core 8, dual-temperature zone cooling and heating core 9 - water side 2.1 of water-cooled condenser 2 - dual-temperature zone cooling and heating core 9.

[0067] In this mode, the water temperatures required for cooling the battery pack 10 and dehumidifying the internal passenger compartment are inconsistent, and a single coolant circuit cannot meet the requirements at the same time. Therefore, the utility model provides two parallel coolant circuits in this mode, which are responsible for heating and dehumidifying the passenger compartment and cooling the battery pack 10 respectively. Both coolant circuits are connected in series with the refrigerant circuit, and the two respectively use the high-temperature refrigerant heat of the condenser and the low-temperature refrigerant heat of the chiller to differentially control the refrigerant evaporation temperature to obtain coolants with different water temperatures, and finally obtain coolants with different water temperatures to achieve different functions.

[0068] In some embodiments of the present invention, when the battery pack 10 is in a high-temperature fast-charging state and the battery pack management module issues a cooling request, the system switches to a forced cooling mode of the battery pack 10. Figure 5 As shown, close the outlet of the second three-way valve 18 leading to the cascade chiller 6, close all outlets of the third three-way valve 19, close the outlet of the fourth three-way valve 20 leading to the water-cooled core 8, close all outlets of the fifth three-way valve 21, the sixth three-way valve 22, and the seventh three-way valve 23, and close the outlet of the first four-way valve 25 and the second four-way valve 26 leading to the water-cooled condenser 2.

[0069] In this mode, the refrigerant module starts normally, and the battery pack management module forms two coolant loops, namely: battery pack 10-first water side 6.2 of cascade Chiller6-battery pack 10, battery pack 10-second water side 6.5 of cascade Chiller6-battery pack 10. The two coolant loops simultaneously enable the first water pump 6.3 and the second water pump 6.6, which can provide the maximum cooling capacity and the maximum coolant flow to meet the cooling requirements of the battery pack 10 during high-temperature fast charging. The loop formed by the motor management module is: EDU cooling unit 12-low-temperature radiator 11-water side 2.1 of the water-cooled condenser 2-EDU cooling unit 12. In the loop formed by the motor management module, the electronic fan 16 is turned on so that the temperature and pressure of the refrigerant side 2.3 of the water-cooled condenser 2 do not exceed the boundary requirements.

[0070] When the battery pack 10 is in a slow charging state, selecting one of the two coolant circuits can provide a sufficient amount of coolant. Different coolant circuits can be selected by controlling the number of openings of the first four-way valve 25 and the second four-way valve 26 and the opening and closing of the first water pump 6.3 and the second water pump 6.6.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the utility model.

Claims

1. A vehicle thermal management system, characterized in that: Including refrigerant module; The refrigerant module comprises a compressor (1), a water-cooled condenser (2), a liquid storage tank (3), an expansion valve (4) and a cascade chiller (6) which are sequentially connected along a refrigerant flow path, the compression and discharge side of the compressor (1) is connected to the inlet of the refrigerant side (2.3) of the water-cooled condenser (2), and the outlet of the refrigerant side (2.3) is connected to the liquid storage tank (3); wherein, The cascade chiller (6) is formed by stacking two chillers, and has a first refrigerant side (6.1), a first water side (6.2), a second refrigerant side (6.4) and a second water side (6.5). The first refrigerant side (6.1) and the second refrigerant side (6.4) are connected in series, the expansion valve (4) is connected to the first refrigerant side (6.1), and the outlet of the second refrigerant side (6.4) is connected to the pressure-suction side of the compressor (1).

2. The vehicle thermal management system according to claim 1, characterized in that: The refrigerant module also includes a hot gas bypass branch arranged between the compressor (1) and the cascade chiller (6), one end of the hot gas bypass branch is connected to the compression and discharge side of the compressor (1), and the other end is connected to the inlet of the second refrigerant side (6.4) of the cascade chiller (6); wherein a two-way ball valve (5) capable of gradually adjusting the opening within the range of cut-off to full opening is arranged on the hot gas bypass branch.

3. The vehicle thermal management system according to claim 2, characterized in that: A first temperature and pressure sensor (33) is provided on the pipeline connecting the discharge side of the compressor (1) and the two-way ball valve (5), and a second temperature and pressure sensor (34) is provided on the pipeline connecting the suction side of the compressor (1) and the cascade chiller (6).

4. The vehicle thermal management system according to claim 1, characterized in that: The vehicle thermal management system also includes a passenger compartment management module, which includes a blower (7), a water-cooled core (8) and a dual-temperature zone heating and cooling core (9) arranged in the passenger compartment air-conditioning assembly. The water-cooled core (8) and the dual-temperature zone heating and cooling core (9) are arranged on the air outlet side of the blower (7). The two ends of the water-cooled core (8) are respectively connected to the two ends of the second water side (6.5) of the cascade chiller (6). The dual-temperature zone heating and cooling core (9) includes a first core temperature zone (9.1) and a second core temperature zone (9.2). The two ends of the first core temperature zone (9.1) and the second core temperature zone (9.2) are respectively connected to the two ends of the first water side (6.2) of the cascade chiller (6).

5. The vehicle thermal management system according to claim 4, characterized in that: The vehicle thermal management system further comprises a battery pack management module, the battery pack management module comprising a battery pack (10), the cooling liquid channels of the battery pack (10) being respectively connected to two ends of the first water side (6.2) of the cascade chiller (6).

6. The vehicle thermal management system according to claim 1, characterized in that: The vehicle thermal management system further comprises a motor management module, the motor management module comprising an EDU cooling unit (12) and a low-temperature radiator (11), the EDU cooling unit (12) and the low-temperature radiator (11) being connected in series with the water side (2.1) of the water-cooled condenser (2) to form a closed loop.

7. The vehicle thermal management system according to claim 6, characterized in that: A first three-way valve (17) is provided on the pipeline connecting the low-temperature radiator (11) and the water-cooled condenser (2), and the other outlet of the first three-way valve (17) is connected to the outlet end of the first water side (6.2) of the cascade chiller (6); a second three-way valve (18) is provided on the pipeline connecting the EDU cooling unit (12) and the water-cooled condenser (2), and the other outlet of the second three-way valve (18) is connected to the inlet end of the first water side (6.2) of the cascade chiller (6).

8. The vehicle thermal management system according to claim 7, characterized in that: A third three-way valve (19) is also provided on the pipeline connecting the first three-way valve (17) and the cascade chiller (6), and another outlet of the third three-way valve (19) is connected to the EDU cooling unit (12).

9. The vehicle thermal management system according to claim 5, characterized in that: A first four-way valve (25) and a second four-way valve (26) are respectively arranged on the pipeline connecting the battery pack (10) and the cascade chiller (6); the first four-way valve (25) is arranged at the inlet end of the cooling liquid channel of the battery pack (10), and the second four-way valve (26) is arranged at the outlet end of the cooling liquid channel of the battery pack (10); the battery pack (10) is connected to the two ends of the second water side (6.5) of the cascade chiller (6) and the two ends of the water side (2.1) of the water-cooled condenser (2) through the first four-way valve (25) and the second four-way valve (26).

10. The vehicle thermal management system according to claim 9, characterized in that: A fourth three-way valve (20) is provided on a pipeline connecting the water-cooling core (8) and the outlet end of the second water side (6.5), and the other outlet of the fourth three-way valve (20) is connected to the first four-way valve (25); an eighth three-way valve (24) is provided on a pipeline connecting the water-cooling core (8) and the inlet end of the second water side (6.5), and the other outlet of the eighth three-way valve (24) is connected to the outlet end of the second water side (6.5).

11. The vehicle thermal management system according to claim 10, characterized in that: A fifth three-way valve (21) is provided on the pipeline connecting the first temperature zone (9.1) of the core body and the outlet end of the first water side (6.2), and the other outlet of the fifth three-way valve (21) is connected to the outlet end of the water side (2.1) of the water-cooled condenser (2); a sixth three-way valve (22) is provided on the pipeline connecting the second temperature zone (9.2) of the core body and the outlet end of the first water side (6.2), and the other outlet of the sixth three-way valve (22) is connected to the outlet end of the water side (2.1) of the water-cooled condenser (2).

12. The vehicle thermal management system according to claim 11, characterized in that: The outlet ends of the first temperature zone (9.1) of the core and the second temperature zone (9.2) of the core are combined into one pipeline, and a seventh three-way valve (23) is arranged on the pipeline connected to the inlet end of the first water side (6.2) of the cascade chiller (6), and the other outlet of the seventh three-way valve (23) is connected to the inlet end of the water side (2.1) of the water-cooled condenser (2).

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