Thermal Management System and Its Control Method

Abstract

The present application discloses a control method for a thermal management system, which obtains the real-time temperature of the battery and the target temperature of the battery; determines the relationship between the difference between the real-time temperature of the battery and the target temperature of the battery and a first threshold. If the difference between the real-time temperature of the battery and the target temperature of the battery is greater than the first threshold, an overheat control strategy is executed. If the difference between the real-time temperature of the battery and the target temperature of the battery is less than or equal to the first threshold, a temperature control strategy is executed. When the difference between the real-time temperature of the battery and the target temperature of the battery is less than or equal to the first threshold, the temperature control strategy is used to adjust the opening degree of the throttle device, and the opening degree of the throttle device is adjusted at least based on the temperature of the battery, reducing the cumbersome steps brought by the calibrated superheat and the possibility of deviation in theoretical calculation, and improving the accuracy of control. The present application also provides a thermal management system for operating the above control method.

Description

Technical Field

[0001] This application relates to the technical field of thermal management, and particularly to a thermal management system and a control method thereof. Background Art

[0002] To meet the requirements of energy conservation and environmental protection, as an important environmental protection tool, new energy vehicles need to address the urgent issue of achieving more energy-efficient battery thermal management.

[0003] The thermal management system of battery vehicles uses a refrigerant system to reduce the temperature of the coolant, and realizes the cooling of battery components through the circulating flow of the coolant. In the related art, the control method of the thermal management system is to adjust the opening of the throttling device according to the outlet superheat degree of the heat exchanger in the refrigerant system, so as to adjust the temperature of the battery components. This method can quickly reduce the temperature of the battery components. According to the temperature of the battery components, the thermal management system has multiple preset superheat degrees, and each preset superheat degree needs to be obtained through multiple calibrations, which is time-consuming and laborious, and there are certain deviations in theoretical calculations, resulting in low adjustment accuracy. The inventor believes that there is a need for improvement. Summary of the Invention

[0004] In view of the above problems in the related art, this application provides a thermal management system and a control method thereof that improve control accuracy.

[0005] On the one hand, this application provides a control method for a thermal management system, including the following steps:

[0006] Provide a thermal management system, the thermal management system includes a throttling device, a double-flow heat exchanger and a battery heat exchange device, and the double-flow heat exchanger includes a first heat exchange part and a second heat exchange part;

[0007] Operate the thermal management system, the outlet of the throttling device is communicated with the inlet of the first heat exchange part, the battery heat exchange device is communicated with the second heat exchange part, and the first heat exchange part exchanges heat with the second heat exchange part;

[0008] Obtain the real-time battery temperature and the target battery temperature; judge the relationship between the difference between the real-time battery temperature and the target battery temperature and a first threshold. If the difference between the real-time battery temperature and the target battery temperature is greater than the first threshold, execute the superheat control strategy. If the difference between the real-time battery temperature and the target battery temperature is less than or equal to the first threshold, execute the temperature control strategy;

[0009] Wherein, the first threshold is a system calibration value, the superheat control strategy adjusts the opening of the throttling device at least based on the state of the fluid flowing out of the first heat exchange part, and the temperature control strategy adjusts the opening of the throttling device at least based on the temperature of the battery.

[0010] In the present application, when the difference between the real-time temperature of the battery and the target temperature of the battery is less than or equal to the first threshold, the opening degree of the throttling device is adjusted using a temperature control strategy, and the opening degree of the throttling device is adjusted at least based on the temperature of the battery, reducing the cumbersome steps caused by the calibrated superheat and the possibility of deviation in theoretical calculations, and improving the accuracy of control.

[0011] On the other hand, the present application provides a thermal management system, including a throttling device, a two-flow heat exchanger, a battery heat exchange device, and a control device. The two-flow heat exchanger includes a first heat exchange part and a second heat exchange part, and the first heat exchange part is not connected to the second heat exchange part. The first heat exchange part can exchange heat with the second heat exchange part. The outlet of the throttling device can be connected to the inlet of the first heat exchange part, the battery heat exchange device can be connected to the second heat exchange part, and the control device runs the control method of the above thermal management system.

[0012] In the present application, the control device of the thermal management system runs the control method of the above thermal management system, which can improve the accuracy of control. Description of the Drawings

[0013] Figure 1 is a schematic connection block diagram of an embodiment of the thermal management system of the present application;

[0014] Figure 2 is a schematic principle diagram of an embodiment of the thermal management device of the present application;

[0015] Figure 3 is a schematic principle diagram of another embodiment of the thermal management device of the present application;

[0016] Figure 4 is a schematic flowchart of an embodiment of the control method of the thermal management system of the present application;

[0017] Figure 5 is a schematic flowchart of a specific embodiment of the control method of the thermal management system of the present application;

[0018] Figure 6 is as Figure 5 shown in a schematic flowchart of an embodiment of step S4;

[0019] Figure 7 is as Figure 5 shown in a schematic flowchart of an embodiment of step S5;

[0020] Figure 8 is a schematic switching logic diagram of the control strategy in the control method of the thermal management system of the present application;

[0021] Figure 9It is a schematic flowchart of another specific embodiment of the control method of the thermal management system of the present application. Detailed implementation manners

[0022] Here, the exemplary embodiments will be described in detail, and the examples are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation manners described in the following exemplary embodiments do not represent all implementation manners consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0023] The terms used in the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The singular forms "a", "the" and "said" used in the present application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0024] It should be understood that the "first", "second" and similar terms used in the specification and claims of the present application do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, the similar terms such as "one" or "a" do not indicate a quantity limitation, but indicate that there is at least one; "multiple" indicates a quantity of two or more. Unless otherwise specified, the similar terms such as "front part", "rear part", "lower part" and / or "upper part" are only for convenience of description and are not limited to one position or a spatial orientation. The terms "including" or "comprising" and similar terms mean that the elements or items appearing before "including" or "comprising" cover the elements or items listed after "including" or "comprising" and their equivalents, and do not exclude other elements or items.

[0025] The following will describe in detail the control method of the thermal management system of the exemplary embodiment of the present application with reference to the drawings. Without conflict, the features in the following embodiments and implementation manners can be mutually supplemented or combined.

[0026] As Figure 1 shown, the thermal management system 100 includes a thermal management device 101 and a control device 102. The control device 102 is electrically connected to some components of the thermal management device 101, and the control device 102 controls the operating state of the thermal management device 101. Optionally, the thermal management system 100 can be applied to a vehicle or indoors such as a residence, a garage, a shopping mall, etc.

[0027] According to an embodiment of the thermal management device 101, taking the thermal management system 100 applied to a vehicle as an example, the thermal management system 100 includes a cabin 200, such as a passenger cabin, etc., and the thermal management system 100 is used to meet the heating or cooling requirements on the cabin side and the battery side.

[0028] Referring to Figure 2 Figure 2 , in this embodiment, the thermal management device 101 includes a refrigerant system 10, a first coolant system 40, and a second coolant system 50. Some components of the refrigerant system 10 are electrically connected to the control device 102, and the control device 102 controls the operating state of the refrigerant system 10 to circulate the refrigerant. Some components of the first coolant system 40 are electrically connected to the control device 102, and the control device 102 controls the operating state of the first coolant system 40 to circulate the first coolant. Some components of the second coolant system 50 are electrically connected to the control device 102, and the control device 102 controls the operating state of the second coolant system 50 to circulate the second coolant. Optionally, the first coolant and the second coolant can be the same fluid or different fluids.

[0029] The thermal management device 101 includes a first heat exchanger 31, a second heat exchanger 32, and a third heat exchanger 60. The first heat exchanger 31, the second heat exchanger 32, and the third heat exchanger 60 are all heat exchangers with two flow channels, such as plate heat exchangers or water-cooled heat exchangers. The first heat exchanger 31 includes a first heat exchange portion 33 and a second heat exchange portion 34. The first heat exchange portion 33 and the second heat exchange portion 34 are not connected. The flow channel of the first heat exchange portion 33 is connected to the refrigerant system 10 for circulating the refrigerant, and the flow channel of the second heat exchange portion 34 is connected to the second coolant system 50 for circulating the second coolant. The first heat exchanger 31 is used for heat exchange between the refrigerant and the second coolant. The second heat exchanger 32 includes a third heat exchange portion 35 and a fourth heat exchange portion 36. The third heat exchange portion 35 and the fourth heat exchange portion 36 are not connected. The flow channel of the third heat exchange portion 35 is connected to the first coolant system 40 for circulating the first coolant, and the flow channel of the fourth heat exchange portion 36 is connected to the second coolant system 50 for circulating the second coolant. The second heat exchanger 32 is used for heat exchange between the first coolant and the second coolant. The third heat exchanger 80 includes a fifth heat exchange portion 61 and a sixth heat exchange portion 62. The fifth heat exchange portion 61 and the sixth heat exchange portion 62 are not connected. The flow channel of the fifth heat exchange portion 61 is connected to the refrigerant system 10 for circulating the refrigerant, and the flow channel of the sixth heat exchange portion 62 is connected to the first coolant system 40 for circulating the first coolant. The third heat exchanger 80 is used for heat exchange between the first coolant and the refrigerant.

[0030] In this embodiment, the refrigerant system 10 includes a compressor 11, a gas-liquid separator 12, an outdoor heat exchanger 13, a first flow regulating device 14, a second flow regulating device 15, a third flow regulating device 16, a first multi-way valve 17, an indoor evaporator 22, a first heat exchange part 33 of a first heat exchanger 31, and a fifth heat exchange part 61 of a third heat exchanger 60. The compressor 11, the first flow regulating device 14, the second flow regulating device 15, the third flow regulating device 16, and the first multi-way valve 17 are respectively electrically connected to a control device 102 and are controlled by the control device 102. The compressor 11 is used to compress the refrigerant, and the gas-liquid separator 12 is used to separate the refrigerant into gas and liquid and discharge the gaseous refrigerant. The first flow regulating device 14 is used to regulate the refrigerant flowing through the outdoor heat exchanger 13 and has the functions of throttling, conducting, and shutting off. The second flow regulating device 15 is arranged in front of the inlet of the indoor evaporator 22, and the second flow regulating device 15 is used to regulate the refrigerant flowing through the indoor evaporator 22 and has the functions of throttling and shutting off. The third flow regulating device 16 is arranged in front of the inlet of the first heat exchange part 33 of the first heat exchanger 31, and the third flow regulating device 16 is used to regulate the refrigerant flowing through the first heat exchange part 33 of the first heat exchanger 31 and has the functions of throttling and shutting off. The first multi-way valve 17 is used to regulate the refrigerant flow rate flowing to the indoor evaporator 22 and the refrigerant flow rate flowing to the first heat exchange part 33 of the first heat exchanger 31. The first multi-way valve 17 includes an inlet and two outlets. Among them, the inlet is used to introduce the refrigerant, one outlet can be connected to the indoor evaporator 22 through the second flow regulating device 15, and the other outlet can be connected to the first heat exchange part 33 of the first heat exchanger 31 through the third flow regulating device 16.

[0031] In some other embodiments, the refrigerant system 10 may not be provided with the gas-liquid separator 12. For example, the compressor 11 has its own gas-liquid separation function. In some other embodiments, the refrigerant system 10 may not be provided with the first multi-way valve 17, and the flow rate may be directly regulated by the second flow regulating device 15 and the third flow regulating device 16; alternatively, the second flow regulating device 15 and the third flow regulating device 16 may not be provided, but a valve member may be arranged in front of the inlet of the first multi-way valve 17 to achieve the functions of throttling and shutting off.

[0032] The first coolant system 40 includes a first fluid driving device 41, a fourth heat exchanger 21, a second multi-way valve 42, a heating device 43, a sixth heat exchange part 62 of a third heat exchanger 60, and a third heat exchange part 35 of a second heat exchanger 32. The first fluid driving device 41, the second multi-way valve 42, and the heating device 43 are electrically connected to a control device 102 and are controlled by the control device 102. The first fluid driving device 41 is used to provide power for driving the first coolant to flow, the heating device 43 is used to heat the first coolant, and the second multi-way valve 42 is used to adjust the flow rate of the first coolant flowing to the fourth heat exchanger 21 and the flow rate of the first coolant flowing to the third heat exchange part 35 of the second heat exchanger 32. The second multi-way valve 42 includes an inlet and two outlets. Among them, the inlet can be communicated with the outlet of the heating device 43, one outlet can be communicated with the fourth heat exchanger 21, and the other outlet can be communicated with the fourth heat exchange part 36.

[0033] The second coolant system 50 includes a battery heat exchange device 51, a motor heat exchange device 52, a fifth heat exchanger 53, an inverter heat exchange device (not shown in the figure), a second fluid driving device 54, a second heat exchange part 34 of a first heat exchanger 31, and a fourth heat exchange part 36 of a second heat exchanger 32. The second fluid driving device 54 is used to provide power for driving the second coolant to flow. The motor heat exchange device 52 is used to adjust the temperature of the motor, the battery heat exchange device 51 is used to adjust the temperature of the battery, and the inverter heat exchange device is used to adjust the temperature of the inverter. The motor, the battery, and the inverter are electrically connected to the control device 102 and are controlled by the control device 102. The second coolant system also includes a plurality of valve parts that are electrically connected to the control device 102 and are controlled by the control device 102. By regulating the working states of the plurality of valve parts, the thermal management of heating devices such as the motor, the battery, and the inverter can be realized, thereby improving the performance of devices such as the motor, the battery, and the inverter. For example, the second coolant system 50 can exchange heat with the atmospheric environment through the fifth heat exchanger 53, thereby dissipating heat from heating devices such as the motor, the battery, and the inverter; it can also perform thermal management on heating devices such as the motor, the battery, and the inverter through the first heat exchanger 31 or the second heat exchanger 32.

[0034] In this embodiment, the outdoor heat exchanger 13, the indoor evaporator 22, the fourth heat exchanger 21, and the fifth heat exchanger 53 are all air-cooled heat exchangers. The outdoor heat exchanger 13 and the fifth heat exchanger 53 are respectively used for heat exchange with the atmospheric environment, and the fourth heat exchanger 21 and the indoor evaporator 22 are respectively used for heat exchange with the cabin body 200. The fourth heat exchanger 21 is used as a warm air core in the system, and the fifth heat exchanger is used as a low-temperature water tank in the system. The structural design principle of the air-cooled heat exchanger is well known to those skilled in the art and will not be elaborated here.

[0035] Optionally, the heating device 43 is a water-cooled PTC heater. The first fluid driving device 41 includes a component which is an electronic water pump. The second fluid driving device 54 includes at least two components, and each component is an electronic water pump.

[0036] The thermal management device 101 includes an air conditioning box 20 and a heat exchange device 30. The air conditioning box 20 exchanges heat with the cabin 200, such as the refrigerant or coolant flowing into the air conditioning box 20 exchanges heat with the cabin 200, etc., to meet the heating or cooling requirements on the cabin side. The heat exchange device 30 exchanges heat with the second coolant system 50, such as the refrigerant or coolant flowing into the heat exchange device 30 directly or indirectly exchanges heat with the battery, etc., to meet the heating or cooling requirements on the battery side. The air conditioning box 20 includes a fourth heat exchanger 21 and an indoor evaporator 22, and the heat exchange device 30 includes a first heat exchanger 31 and a second heat exchanger 32.

[0037] The thermal management system 100 includes operating modes such as a heating mode, a heating and dehumidifying mode, and a cooling mode. The refrigerant system 10 of the thermal management system 100 further includes a fluid switching device 18 for switching the flow direction of the refrigerant. The fluid switching device 18 is electrically connected to the control device 102 and is controlled by the control device 102 to control and switch the working state of the fluid switching device 18, so as to switch the operating mode of the thermal management system 100. For example, the working state of the fluid switching device 18 may include a first working state and a second working state. In the first working state, the thermal management system 100 operates in the heating mode or the heating and dehumidifying mode. In the second working state, the thermal management system 100 operates in the cooling mode.

[0038] Specifically, the following describes an exemplary process of the thermal management system 100 in different operating modes.

[0039] In the heating mode, the first flow regulating device 14 is in a throttling state, the second flow regulating device 15 is in a cut-off state, the third flow regulating device 16 is in a cut-off state, and the fluid switching device 18 is in the first working state. The compressor 11, the fifth heat exchange part 61 of the third heat exchanger 60, the first flow regulating device 14, the outdoor heat exchanger 13, the gas-liquid separator 12, and the compressor 11 are sequentially connected to form a refrigerant circuit. The first fluid driving device 41, the sixth heat exchange part 62 of the third heat exchanger 60, the heating device 43, the second multi-way valve 42, the fourth heat exchanger 21, and the first fluid driving device 41 are sequentially connected to form a coolant circuit, and the first fluid driving device 41 is in a working state to provide power for the flow of the first coolant. The fourth heat exchanger 21 releases heat, and the air conditioning box 20 outputs hot air to the cabin 200 to raise the temperature of the cabin 200.

[0040] In the heating and dehumidifying mode, the first flow regulating device 14 is in a throttling state, the second flow regulating device 15 is in a throttling state, the third flow regulating device 16 is in a cut-off state, and the fluid switching device 18 is in the first working state. The compressor 11, the fifth heat exchange part 61 of the third heat exchanger 60, the first flow regulating device 14, the outdoor heat exchanger 13, the gas-liquid separator 12, and the compressor 11 are sequentially connected to form a refrigerant circuit. The compressor 11, the fifth heat exchange part 61 of the third heat exchanger 60, the first multi-way valve 17, the second flow regulating device 15, the indoor evaporator 22, the gas-liquid separator 12, and the compressor 11 are sequentially connected to form a refrigerant circuit. The first fluid driving device 41, the sixth heat exchange part 62 of the third heat exchanger 60, the heating device 43, the second multi-way valve 42, the fourth heat exchanger 21, and the first fluid driving device 41 are sequentially connected to form a coolant circuit. The first fluid driving device 41 is in a working state to provide power for the flow of the first coolant. In the air conditioner box 20, the air first flows through the relatively low-temperature indoor evaporator 22 for dehumidification, and then flows through the fourth heat exchanger 21 to be heated, so as to realize the function of heating and dehumidifying. At this time, the air conditioner box 20 outputs dry hot air to the cabin 200 to increase the temperature of the cabin 200.

[0041] In the heating mode and the heating and dehumidifying mode, by adjusting the second multi-way valve 42, part of the first coolant can flow through the third heat exchange part 35 of the second heat exchanger 32, and heat exchange with the second coolant in the second coolant system 50 through the second heat exchanger 32, so as to dissipate heat to the atmospheric environment, or perform thermal management on heat-generating devices such as motors, batteries, and inverters.

[0042] In the refrigeration mode, the first fluid driving device 41 stops working, the first flow regulating device 14 is in a conducting state, the second flow regulating device 15 is in a throttling state, and the fluid switching device 18 is in the second working state. The compressor 11, the fifth heat exchange part 61 of the third heat exchanger 60, the outdoor heat exchanger 13, the first flow regulating device 14, the second flow regulating device 15, the indoor evaporator 22, the gas-liquid separator 12, and the compressor 11 are sequentially connected to form a refrigerant circuit. The indoor evaporator 22 absorbs heat, and the air conditioner box 20 outputs cold air to the cabin 200 to reduce the temperature of the cabin 200. In the refrigeration mode, by adjusting the first multi-way valve 17, part of the refrigerant flows through the first heat exchange part 33 of the first heat exchanger 31, and the third flow regulating device 16 is in a throttling state. Heat exchange with the second coolant in the second coolant system 50 through the first heat exchanger 31 to perform thermal management on heat-generating devices such as motors, batteries, and inverters.

[0043] The thermal management system 100 may also include multiple sensors, such as a sensor at the outlet of the air-conditioning box 20, a sensor at the outlet of the compressor 11, a sensor at the outdoor heat exchanger 13, and a sensor at the indoor evaporator 22. The above multiple sensors are all electrically connected to the control device 102 to send the detected temperature signals to the control device 102, so that the control device 102 can more accurately judge the working status of each component.

[0044] According to another embodiment of the thermal management device 101, it can be used to cool the battery. Figure 3 As shown, the thermal management device 101 includes a compressor 11, a condenser 300, a third flow regulating device 16, a first heat exchanger 31, a second fluid driving device 54 and a battery heat exchange device 51. The first heat exchanger 31 includes a first heat exchange part 33 and a second heat exchange part 34, and the first heat exchange part 33 is not connected to the second heat exchange part 34. When the thermal management device is in operation, the compressor 11, the condenser 300, the third flow regulating device 16 and the first heat exchange part 33 are connected to form a refrigerant circuit, the second fluid driving device 54, the battery heat exchange device 51 and the second heat exchange part 34 are connected to form a coolant circuit, and the refrigerant in the first heat exchange part 33 is heat-exchanged with the coolant in the second heat exchange part 34. When the thermal management device is running, the outlet of the compressor 11 is connected to the inlet of the condenser 300, the outlet of the condenser 300 is connected to the inlet of the third flow regulating device 16, the outlet of the third flow regulating device 16 is connected to the inlet of the first heat exchange part 33, the outlet of the first heat exchange part 33 is connected to the inlet of the compressor 11, the third flow regulating device 16 is in a throttling state, the refrigerant in the first heat exchange part 33 absorbs the heat of the coolant in the second heat exchange part 34, and the coolant with reduced temperature flows through the battery heat exchange device to achieve battery cooling.

[0045] The control device 102 in the embodiment of the present application can be any device with acquisition and computing capabilities, for example, it can be a computer terminal, an industrial computer, etc. The control device 102 can obtain the operating mode of the thermal management device 101, and the control device 102 can send a corresponding control signal to at least one component in the thermal management device 101 to control the working state of the corresponding component.

[0046] The present application also provides a control method for a thermal management system, which can be applied to the above Figures 1 to 3 In the example of the thermal management device 101 provided, when the battery has a cooling liquid demand, the control device 102 executes the control method. The specific implementation of the thermal management device 101 is not repeated here, and reference may be made to the above description of the thermal management device 101.

[0047] The control method of the thermal management system 100 provided in the embodiment of the present application is described in detail below. Specifically,Figure 4 As shown, the method includes the following steps:

[0048] S1. Obtain the real-time temperature of the battery and the target temperature of the battery;

[0049] S2. Judge the relationship between the difference between the real-time temperature of the battery and the target temperature of the battery and a first threshold. If the difference between the real-time temperature of the battery and the target temperature of the battery is greater than the first threshold, execute the superheat control strategy. If the difference between the real-time temperature of the battery and the target temperature of the battery is less than or equal to the first threshold, execute the temperature control strategy.

[0050] In this embodiment, the throttling device is the third flow regulating device 16. The real-time temperature of the battery is the real-time temperature of the coolant at the inlet of the battery heat exchange device 51, which can be detected by a sensor arranged at the inlet of the battery heat exchange device 51. The target temperature of the battery is the target temperature of the coolant at the inlet of the battery heat exchange device 51, which can be obtained by the system according to the temperature state of the battery. The superheat control strategy is to adjust the opening of the throttling device based on the state of the refrigerant at the outlet of the first heat exchange part, which has the advantage of being able to quickly reduce the temperature of the coolant and can quickly reduce the temperature of the battery. Optionally, the state of the refrigerant includes the superheat of the refrigerant, and the superheat of the refrigerant is related to the temperature and pressure of the refrigerant. The temperature control strategy is to adjust the opening of the throttling device based on the temperature of the coolant at the inlet of the battery heat exchange device 51, which has the advantage of being able to accurately adjust the temperature of the coolant and can accurately adjust the temperature of the battery. It should be noted that in other embodiments, the real-time temperature of the battery can also be the real-time temperature of the coolant at the outlet of the battery heat exchange device 51, or the real-time temperature of the battery itself. Similarly, the target temperature of the battery is the target temperature of the coolant at the outlet of the battery heat exchange device 51, or the target temperature of the battery itself.

[0051] According to an embodiment of the control method of the thermal management system of the present application, refer to Figures 5 to 7 Steps S2 include the following steps:

[0052] S21. Judge whether the difference between the current temperature of the battery and the target temperature of the battery is greater than the first threshold.

[0053] S22. Execute the temperature control strategy.

[0054] S23. Execute the superheat control strategy.

[0055] Specifically, when the difference between the current temperature of the battery and the target temperature of the battery is greater than the first threshold, execute step S23; when the difference between the current temperature of the battery and the target temperature of the battery is less than or equal to the first threshold, execute step S22. Among them, the first threshold is a system calibration value. Optionally, the first threshold is greater than zero.

[0056] If the difference between the current temperature of the battery and the target temperature of the battery is greater than the first threshold, it indicates that the current temperature of the battery is much higher than the target temperature of the battery, and the current temperature of the battery is relatively high. Then, the superheat control strategy is executed, and the battery can be cooled down relatively quickly. If the difference between the current temperature of the battery and the target temperature of the battery is less than or equal to the first threshold, it indicates that the current temperature of the battery is relatively close to the target temperature of the battery at this time. If the superheat control strategy continues to be used, the temperature of the coolant will be too low, affecting the performance of the battery. Therefore, the temperature control strategy is executed, and the temperature of the coolant can be adjusted more accurately, so that the difference between the current temperature of the battery and the target temperature of the battery is smaller.

[0057] Before step S2 or in step S2 of the method of the present application, step 10 is further included. Specifically, step S10 is to obtain the current superheat of the first heat exchange part.

[0058] The current superheat of the first heat exchange part is the real-time superheat at the outlet of the first heat exchange part. The current superheat of the first heat exchange part is related to the current temperature and the current pressure of the first heat exchange part. The current temperature of the first heat exchange part is the real-time temperature of the refrigerant at the outlet of the first heat exchange part, and the current pressure of the first heat exchange part is the real-time pressure of the refrigerant at the outlet of the first heat exchange part. Both the current temperature and the current pressure of the first heat exchange part can be obtained by sensors. Specifically, obtain the current temperature and the current pressure of the first heat exchange part, and obtain the current superheat of the first heat exchange part based on the current temperature and the current pressure of the first heat exchange part. Optionally, obtain the saturation temperature corresponding to the current pressure of the first heat exchange part according to the current pressure of the first heat exchange part, and then subtract the current temperature of the first heat exchange part from the saturation temperature to obtain the current superheat of the first heat exchange part.

[0059] When step S10 is set before step S2, step S10 can be executed before step S1, or after step S1, or both at the same time. When step S10 is set in step S2, step S10 can be executed once, before step S21; step S10 can also be executed twice, before step S22 and before step S23 respectively, or in step S22 and in step S23 respectively. As long as it does not affect the normal operation of the method, the present application does not limit it.

[0060] Further, as Figure 6 shown, step S22 includes:

[0061] S24. Determine whether the current superheat of the first heat exchange part is greater than the second threshold.

[0062] When the current superheat degree of the first heat exchange part is greater than the second threshold value, step S25 is executed; when the current superheat degree of the first heat exchange part is less than or equal to the second threshold value, step S26 is executed. The second threshold value is a system calibration value. Optionally, the second threshold value is less than 5°C and greater than 0°C. Optionally, the second threshold value is less than 5°C and greater than 2°C. Optionally, the second threshold value is 3°C.

[0063] S25. Control the opening degree of the throttling device based on the current temperature of the battery and the target temperature of the battery.

[0064] In this embodiment, controlling the opening degree of the throttling device based on the current temperature of the battery and the target temperature of the battery means performing an operation on the current temperature of the battery and the target temperature of the battery to obtain the target opening degree of the throttling device, and then adjusting the opening degree of the throttling device to the target opening degree. Optionally, the operation type is PI operation or PID operation.

[0065] S26. Determine whether the current temperature of the battery is greater than the target temperature of the battery.

[0066] When the current temperature of the battery is greater than the target temperature of the battery, step S27 is executed; when the current temperature of the battery is less than or equal to the target temperature of the battery, step S25 is executed.

[0067] S27. Keep the opening degree of the throttling device unchanged. Specifically, the opening degree of the throttling device uses the opening degree of the throttling device in the previous cycle.

[0068] The current superheat degree of the first heat exchange part is related to the opening degree of the throttling device. Specifically, the larger the opening degree of the throttling device, the smaller the current superheat degree of the first heat exchange part. When the current superheat degree of the first heat exchange part is less than or equal to the second threshold value, the state of the refrigerant is not easy to determine, which is not conducive to the control of the thermal management device 101. When the current superheat degree of the first heat exchange part is greater than the second threshold value, it indicates that the opening degree of the throttling device can still be adjusted. Control the opening degree of the throttling device based on the current temperature of the battery and the target temperature of the battery, and adjust the temperature of the coolant, so that the difference between the current temperature of the battery and the target temperature of the battery is smaller. When the current superheat degree of the first heat exchange part is less than or equal to the second threshold value, further judge the relationship between the current temperature of the battery and the target temperature of the battery. If the current temperature of the battery is greater than the target temperature of the battery, that is, the battery temperature still needs to be reduced, but the current superheat degree of the first heat exchange part cannot be reduced any more, so keep the opening degree of the throttling device unchanged, so that the current superheat degree of the first heat exchange part will not be reduced any more; if the current temperature of the battery is less than or equal to the target temperature of the battery, that is, the temperature of the coolant may be too low at this time, control the opening degree of the throttling device based on the current temperature of the battery and the target temperature of the battery, and adjust the temperature of the coolant, so that the difference between the current temperature of the battery and the target temperature of the battery is smaller.

[0069] In some other embodiments, refer to Figure 6, Step S22 further includes Step S10, which is executed before Step S24.

[0070] Furthermore, as Figure 7 shown, Step S23 includes:

[0071] S28. Obtain the target superheat of the first heat exchange part.

[0072] S29. Control the opening degree of the throttling device based on the current superheat of the first heat exchange part and the target superheat of the first heat exchange part.

[0073] In this embodiment, the target superheat of the first heat exchange part is the target superheat at the outlet of the first heat exchange part, and the target superheat of the first heat exchange part is a system calibration value. Optionally, the target superheat of the first heat exchange part is 5°C. Controlling the opening degree of the throttling device based on the current superheat of the first heat exchange part and the target superheat of the first heat exchange part is to perform an operation on the current superheat of the first heat exchange part and the target superheat of the first heat exchange part, so as to obtain the target opening degree of the throttling device, and then adjust the opening degree of the throttling device to the target opening degree. Optionally, the operation type is PI operation or PID operation.

[0074] In some other embodiments, referring to Figure 7 , Step S23 further includes Step S10, which is executed before Step S29, that is, Step S10 can be executed before Step S28, can be executed after Step S28, or can be executed simultaneously with both.

[0075] As Figure 8 shown, after determining the control strategy for the opening degree of the throttling device according to the above steps, the method further includes the following steps: The thermal management system 100 executes the superheat control strategy, and when the difference between the real-time battery temperature and the target battery temperature is less than the third threshold, it switches to execute the temperature control strategy. The thermal management system 100 executes the temperature control strategy, and when the difference between the real-time battery temperature and the target battery temperature is greater than the first threshold, it switches to execute the superheat control strategy. The third threshold is a system calibration value, and the third threshold is less than the first threshold. Optionally, the third threshold is greater than zero.

[0076] In the method of the present application, a buffer interval for the thermal management system 100 to switch between the superheat control strategy and the temperature control strategy is reserved, avoiding frequent switching of the control strategy of the system due to a single system calibration value, which is beneficial to improving the system stability.

[0077] Compared with the related art, in the control method of the present application, according to the relationship between the difference between the current temperature of the battery and the target temperature of the battery and the first threshold, a control strategy for the opening degree of the throttling device is selected. Specifically, when the difference between the current temperature of the battery and the target temperature of the battery is large, implementing the superheat control strategy can more quickly reduce the temperature of the battery; when the current temperature of the battery is relatively close to the target temperature of the battery, implementing the temperature control strategy can more accurately adjust the temperature of the coolant. When implementing the superheat control strategy, the target superheat of the first heat exchange part is a fixed value, which reduces the cumbersome process of calibrating the superheat, reduces the complexity of the control method, and also reduces the theoretical calculation steps, thereby reducing the possibility of deviation in the output result. Performing PI operation or PID operation on the current value and the target value improves the accuracy of the control method.

[0078] According to a specific embodiment of the control method of the thermal management system of the present application, referring to Figure 9 , the method includes the following steps:

[0079] S1. Obtain the current temperature of the battery and the target temperature of the battery.

[0080] S10. Obtain the current superheat of the first heat exchange part.

[0081] S21. Determine whether the difference between the current temperature of the battery and the target temperature of the battery is greater than the first threshold.

[0082] If the difference between the current temperature of the battery and the target temperature of the battery is greater than the first threshold, execute step S28, and then execute step S29; if the difference between the current temperature of the battery and the target temperature of the battery is less than or equal to the first threshold, execute step S24.

[0083] S28. Obtain the target superheat of the first heat exchange part.

[0084] S29. Control the opening degree of the throttling device based on the current superheat of the first heat exchange part and the target superheat of the first heat exchange part.

[0085] Specifically, perform an operation on the current superheat of the first heat exchange part and the target superheat of the first heat exchange part, obtain the target opening degree of the throttling device according to the operation result, and adjust the opening degree of the throttling device to the target opening degree.

[0086] S24. Determine whether the current superheat of the first heat exchange part is greater than the second threshold.

[0087] If the current superheat of the first heat exchange part is greater than the second threshold, execute step S25; if the current superheat of the first heat exchange part is less than or equal to the second threshold, execute step S26.

[0088] S25. Control the opening degree of the throttling device based on the current temperature of the battery and the target temperature of the battery.

[0089] Specifically, the current temperature and the target temperature of the battery are calculated, and the target opening of the throttling device is obtained according to the calculation result, and the opening of the throttling device is adjusted to the target opening.

[0090] S26. Determine whether the current temperature of the battery is greater than the target temperature of the battery.

[0091] If the current temperature of the battery is greater than the target temperature of the battery, step S27 is executed; if the current temperature of the battery is less than or equal to the target temperature of the battery, step S25 is executed.

[0092] S27. Keep the opening of the throttling device unchanged.

[0093] It should be understood that the "system calibration value" in this application refers to the value given by the inventor through a large number of experiments or R & D experiences, and is preset in the control device 102.

[0094] In this application, P in the PID algorithm is the abbreviation of Proportional, I is the abbreviation of Integral, and D is the abbreviation of Differential. As the name implies, the PID algorithm is a control algorithm that combines three links of proportional, integral and differential. The essence of the PID algorithm is to perform operations according to the input deviation value according to the functional relationships of proportional, integral and differential. The operation result is used to control the output. Through the combination of these three algorithms, the deviation of the controlled object can be effectively corrected, so that it reaches a stable state.

[0095] P in the PI algorithm is the abbreviation of Proportional, I is the abbreviation of Integral, and the PI algorithm is a control algorithm that combines proportional and integral. According to the given value and the actual output value, a control deviation is formed, and the proportion and integral of the deviation are linearly combined to form a control quantity to control the controlled object.

[0096] In the embodiment of this application, the control device 102 of the thermal management system 100 includes: an acquisition module for acquiring the current temperature and the target temperature of the battery; a processing module for selecting to execute the superheat control strategy or the temperature control strategy at least according to the relationship between the real-time temperature of the battery and the target temperature of the battery, and adjusting the opening of the throttling device.

[0097] Further, the processing module is further configured to judge the magnitude relationship between the difference between the current temperature of the battery and the target temperature of the battery and the first threshold, and select the control strategy for the opening of the throttling device of the thermal management system 100.

[0098] Further, the obtaining module is further configured to obtain the current superheat degree of the first heat exchange part; the processing module is further configured to determine the magnitude relationship between the current superheat degree of the first heat exchange part and a second threshold value and the magnitude relationship between the current temperature of the battery and the target temperature of the battery, and select to keep the opening degree of the throttling device unchanged, or select to control the opening degree of the throttling device based on the current temperature of the battery and the target temperature of the battery.

[0099] Further, the obtaining module is further configured to obtain the current superheat degree and the target superheat degree of the first heat exchange part, and the processing module is further configured to adjust the opening degree of the throttling device based on the current superheat degree and the target superheat degree of the first heat exchange part.

[0100] The obtaining module is electrically connected to the processing module and is configured to execute the Figures 4 to 9 control method provided above. For the specific steps or principles, reference can be made to the description of the control method and will not be elaborated here.

[0101] It should be understood that in this application, obtaining a certain stage result according to parameter A and parameter B means that when obtaining a certain stage result, at least parameter A and parameter B are used, but other parameters may also be used to obtain this stage result. For example, controlling the opening degree ratio of the multi-way valve according to the current air outlet temperature and the target air outlet temperature means controlling the opening degree ratio of the multi-way valve based at least on the current air outlet temperature and the target air outlet temperature.

[0102] It should be understood that the division of each module of the thermal management system shown in the above figures is only a division of logical functions. When implemented, it can be fully or partially integrated into a physical entity, or physically separated. And these modules can all be implemented in the form of software called by processing elements; they can also all be implemented in the form of hardware; or some modules can be implemented in the form of software called by processing elements, and some modules can be implemented in the form of hardware. For example, the processing module can be a separately established processing element or can be integrated in a certain chip of the thermal management system. The implementation of other modules is similar. In addition, all or part of these modules can be integrated together or can be independently implemented. During the implementation process, each step of the above method or each of the above modules can be completed by the integrated logic circuit in the processor element or the instruction in the form of software.

[0103] For example, the above-mentioned modules may be one or more integrated circuits configured to implement the above methods, such as: one or more Application Specific Integrated Circuits (ASICs), or one or more Digital Signal Processors (DSPs), or one or more Field Programmable Gate Arrays (FPGAs), etc. Again, these modules may be integrated together and implemented in the form of a System-On-a-Chip (SOC).

[0104] In the above embodiments, the involved processors may include, for example, CPUs, DSPs, microcontrollers or digital signal processors, and may also include GPUs, Neural-network Process Units (NPUs), and Image Signal Processings (ISPs). The processor may also include necessary hardware accelerators or logic processing hardware circuits, such as ASICs, or one or more integrated circuits for controlling the execution of the technical solution of this application. In addition, the processor may have the function of operating one or more software programs, and the software programs may be stored in a storage medium.

[0105] The embodiment of this application also provides a computer-readable storage medium storing a computer program, which, when running on a computer, causes the computer to execute the method provided by the embodiment shown in this application Figures 4 to 9 shown in this application.

[0106] The embodiment of this application also provides a computer program product including a computer program, which, when running on a computer, causes the computer to execute the method provided by the embodiment shown in this application Figures 4 to 9 shown in this application.

[0107] In the embodiments of the present application, "at least one" means one or more, and "a plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent the cases of A existing alone, A and B existing simultaneously, and B existing alone. Here, A and B can be singular or plural. The character " / " generally represents an "or" relationship between the associated objects before and after. "At least one of the following" and its similar expressions refer to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, and c can represent: a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, and c can be single or multiple.

[0108] Those of ordinary skill in the art can realize that the various units and algorithm steps described in the embodiments disclosed herein can be implemented by a combination of electronic hardware, computer software, and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present application.

[0109] Those skilled in the art can clearly understand that for the convenience and conciseness of description, the specific working processes of the systems, devices, and units described above can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated herein.

[0110] In several embodiments provided by the present application, if any function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the related technology, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (hereinafter referred to as ROM), random access memories (hereinafter referred to as RAM), magnetic disks, or optical discs that can store program codes.

[0111] The above is only the specific implementation manner of the present application. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application and should be covered by the protection scope of the present application. The protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A control method for a thermal management system, characterized in that, The control method includes the following steps: Provide a thermal management system, which includes a throttling device (16), a first heat exchanger (31) and a battery heat exchange device (51). The first heat exchanger (31) includes a first heat exchange part (33) and a second heat exchange part (34); Operate the thermal management system. The outlet of the throttling device (16) is communicated with the inlet of the first heat exchange part (33), the battery heat exchange device (51) is communicated with the second heat exchange part (34), and heat exchange occurs between the first heat exchange part (33) and the second heat exchange part (34); Obtain the real-time battery temperature and the target battery temperature; judge the relationship between the difference between the real-time battery temperature and the target battery temperature and a first threshold. If the difference between the real-time battery temperature and the target battery temperature is greater than the first threshold, execute the superheat control strategy. If the difference between the real-time battery temperature and the target battery temperature is less than or equal to the first threshold, execute the temperature control strategy; Wherein, the first threshold is a system calibration value. The superheat control strategy adjusts the opening degree of the throttling device at least based on the state of the fluid flowing out of the first heat exchange part, and the temperature control strategy adjusts the opening degree of the throttling device at least based on the temperature of the battery; Before the step of judging the relationship between the difference between the real-time battery temperature and the target battery temperature and the first threshold, or after the step of judging the relationship between the difference between the real-time battery temperature and the target battery temperature and the first threshold, the following steps are further included: obtain the current superheat of the first heat exchange part; In the step of obtaining the current superheat of the first heat exchange part, the following steps are included: obtain the current temperature and the current pressure of the first heat exchange part, and obtain the current superheat of the first heat exchange part based on the current temperature and the current pressure of the first heat exchange part; wherein, the current temperature of the first heat exchange part is the current temperature of the fluid flowing out of the first heat exchange part, and the current pressure of the first heat exchange part is the current pressure of the fluid flowing out of the first heat exchange part; In the step of if the difference between the real-time battery temperature and the target battery temperature is greater than the first threshold, execute the superheat control strategy, the following steps are included: obtain the target superheat of the first heat exchange part, and control the opening degree of the throttling device based on the target superheat and the current superheat of the first heat exchange part.

2. The control method of the thermal management system according to claim 1, characterized in that, In the step of controlling the opening degree of the throttling device based on the target superheat and the current superheat of the first heat exchange part, the following steps are included: Perform an operation on the target superheat and the current superheat of the first heat exchange part, and control the opening degree of the throttling device according to the operation result.

3. The control method of the thermal management system according to claim 1, characterized in that, In the step of if the difference between the real-time battery temperature and the target battery temperature is less than or equal to the first threshold, execute the temperature control strategy, the following steps are included: Based on the relationship between the current superheat degree of the first heat exchange part and the second threshold value and the relationship between the real-time temperature of the battery and the target temperature of the battery, select to control the opening degree of the throttling device based on the real-time temperature of the battery and the target temperature of the battery, or select to keep the opening degree of the throttling device unchanged; Wherein, the second threshold value is a system calibration value.

4. The control method of the thermal management system according to claim 3, characterized in that, In the step of based on the relationship between the current superheat degree of the first heat exchange part and the second threshold value and the relationship between the real-time temperature of the battery and the target temperature of the battery, select to control the opening degree of the throttling device based on the real-time temperature of the battery and the target temperature of the battery, or select to keep the opening degree of the throttling device unchanged, the following steps are included: If the current superheat degree of the first heat exchange part is greater than the second threshold value, or the current superheat degree of the first heat exchange part is less than or equal to the second threshold value and the real-time temperature of the battery is less than or equal to the target temperature of the battery, control the opening degree of the throttling device based on the real-time temperature of the battery and the target temperature of the battery; If the current superheat degree of the first heat exchange part is less than or equal to the second threshold value and the real-time temperature of the battery is greater than the target temperature of the battery, keep the opening degree of the throttling device unchanged.

5. The control method of the thermal management system according to claim 3 or 4, characterized in that, In the step of controlling the opening degree of the throttling device based on the real-time temperature of the battery and the target temperature of the battery, the following steps are included: Perform an operation on the real-time temperature of the battery and the target temperature of the battery, and control the opening degree of the throttling device according to the operation result.

6. The control method of the thermal management system according to claim 1, wherein After the step of judging the relationship between the difference between the real-time temperature of the battery and the target temperature of the battery and the first threshold value; if the difference between the real-time temperature of the battery and the target temperature of the battery is greater than the first threshold value, execute the superheat degree control strategy, if the difference between the real-time temperature of the battery and the target temperature of the battery is less than or equal to the first threshold value, execute the temperature control strategy, the following steps are further included: After selecting to execute the superheat degree control strategy, when the difference between the real-time temperature of the battery and the target temperature of the battery is less than the third threshold value, switch to execute the temperature control strategy; After selecting to execute the temperature control strategy, when the difference between the real-time temperature of the battery and the target temperature of the battery is greater than the first threshold value, switch to the superheat degree control strategy; Wherein, the third threshold value is a system calibration value, the third threshold value is less than the first threshold value, and the third threshold value is greater than zero.

7. A thermal management system, characterized in that, It includes a throttling device, a double-flow channel heat exchanger, a battery heat exchange device and a control device. The double-flow channel heat exchanger includes a first heat exchange part and a second heat exchange part. The first heat exchange part and the second heat exchange part are not connected. The first heat exchange part can perform heat exchange with the second heat exchange part. The outlet of the throttling device can be connected to the inlet of the first heat exchange part. The battery heat exchange device can be connected to the second heat exchange part. The control device runs the control method of the thermal management system according to any one of claims 1-6.

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