Automobile thermal management system and control method thereof

Abstract

The invention provides an automobile thermal management system and a control method thereof, and belongs to the technical field of automobile thermal management. The automobile thermal management system comprises a sensor module, a control module and an execution module, the sensor module comprises a battery temperature sensor and an evaporator temperature sensor, and the execution module comprises a refrigerant stop valve and a compressor. After an automobile is powered on, the refrigerant stop valve is in a closed state, and the battery temperature sensor and the evaporator temperature sensor collect temperature information of a battery and temperature information of an evaporator respectively and input the temperature information to the control module. The control module sends a control instruction to the execution module according to the battery temperature, the evaporator temperature and the evaporator temperature when the refrigerant stop valve jumps, and controls opening or closing of the refrigerant stop valve and the power of the compressor to adjust the temperature of the battery and the cockpit. According to the invention, the comfort of a driver and passengers is improved, and the safety of the battery is protected.

Description

Technical Field

[0001] The present invention belongs to the technical field of automobile thermal management, and in particular, relates to an automobile thermal management system and a control method thereof. Background Art

[0002] For new energy vehicles, the passenger compartment temperature must be kept comfortable so that the driver can drive with peace of mind; at the same time, the battery must be kept at a suitable temperature so that it can work at maximum efficiency and be safe and stable. This requires that when both the passenger compartment and the battery have cooling needs, the limited cooling capacity must be reasonably allocated to meet the cooling needs of the passenger compartment and the battery at the same time.

[0003] Chinese patent 110576766B provides a vehicle heat exchange system, in which the battery heat exchanger in the system achieves heating, cooling, temperature balance, etc. of the battery pack through the phase change of the refrigerant and the heat exchange with the battery pack. The low-pressure gaseous refrigerant is compressed into a high-pressure gaseous refrigerant by a compressor and then transported to the location where heat exchange is required. Moreover, when thermal insulation from the external environment is required, only a thin gaseous refrigerant exists in the battery heat exchanger. At this time, the battery heat exchanger realizes thermal insulation capability, blocks the conduction of heat between battery cells, and prevents the thermal runaway phenomenon from spreading between battery cells. When the temperature of the battery pack approaches or reaches the critical temperature of thermal runaway, the high-pressure and low-temperature liquid refrigerant in the refrigerant storage tank is sprayed from the refrigerant spray device to cool the battery heat exchanger and the battery cells.

[0004] This patent does not take into account the cooling needs in the cockpit when cooling the battery, which will cause the temperature in the cockpit to rise and affect the comfort of the driver and passengers in the vehicle. Summary of the invention

[0005] The present invention aims to provide an automobile thermal management system and a control method thereof, so as to achieve the technical purpose of balancing and regulating the temperature of the automobile cockpit and the temperature of the automobile battery.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] The present invention provides an automobile thermal management system, comprising a sensor module, a control module and an execution module, wherein the output end of the sensor module is connected to the input end of the control module, and the output end of the control module is connected to the input end of the execution module.

[0008] The sensor module inputs battery temperature information and evaporator temperature information to the control module, and the control module outputs control instructions to the execution module.

[0009] The sensor module comprises a battery temperature sensor and an evaporator temperature sensor, and the output end of the battery temperature sensor and the output end of the evaporator temperature sensor are respectively connected to the input end of the control module.

[0010] The control module adopts a microcontroller.

[0011] The execution module adopts a refrigerant stop valve and a compressor, and the output end of the control module is respectively connected to the input end of the refrigerant stop valve and the input end of the compressor.

[0012] The present invention provides a control method for an automobile thermal management system:

[0013] After the car is powered on, the refrigerant shut-off valve is closed, and the battery temperature sensor and the evaporator temperature sensor respectively collect the temperature information of the battery and the temperature information of the evaporator and input them into the control module;

[0014] When the evaporator temperature is greater than the evaporator target temperature and the battery temperature is less than or equal to the first battery target temperature, the control module controls the refrigerant stop valve to maintain a closed state;

[0015] When the evaporator temperature is less than or equal to the evaporator target temperature and the battery temperature is less than or equal to the first battery target temperature, the control module controls the refrigerant stop valve to open;

[0016] When the evaporator temperature is less than or equal to the evaporator target temperature and the battery temperature is greater than the first target battery temperature, the control module controls the refrigerant stop valve to open;

[0017] When the evaporator temperature is greater than the evaporator target temperature and the battery temperature is greater than the first target battery temperature, the control module controls the refrigerant temperature cut-off valve to open and increases the operating power of the compressor.

[0018] After the refrigerant stop valve is opened, when the battery temperature is lower than the second target battery temperature, the evaporator temperature is higher than the evaporator target temperature, and the evaporator rise temperature exceeds the first calibration value, the control module controls the refrigerant stop valve to close.

[0019] The first calibration value is the difference between the actual evaporator temperature and the evaporator temperature when the refrigerant stop valve was last opened.

[0020] After the refrigerant stop valve is opened and then closed, when the evaporator temperature drops to exceed the second calibration value, the control module controls the refrigerant stop valve to open again.

[0021] The second calibration value is the difference between the actual evaporator temperature and the evaporator temperature when the refrigerant stop valve was last closed.

[0022] The technical effects of the present invention are:

[0023] (1) The present invention solves the cooling requirements of the cockpit and the battery by only using a refrigerant stop valve and a compressor, thereby reducing costs and the probability of failure.

[0024] (2) The present invention takes into account the cooling requirements of the cockpit and the battery, and realizes cooling distribution by accurately controlling the opening and closing of the refrigerant stop valve, thereby solving the cooling requirements of the cockpit and the battery.

[0025] (3) The present invention reduces the temperature fluctuation in the cockpit and improves the driver's comfort while protecting the battery safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] This specification includes the following drawings, which show the following contents:

[0027] Figure 1 A logical structure diagram of an automobile thermal management system and a control method thereof according to the present invention;

[0028] Figure 2 A thermal management principle block diagram of an automobile thermal management system and a control method thereof according to the present invention;

[0029] Figure 1 Marked as: 1. sensor module; 2. control module; 3. execution module. DETAILED DESCRIPTION

[0030] The specific implementation methods of the present invention are further explained in detail below by describing the embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention and facilitating their implementation.

[0031] The present invention provides an automobile thermal management system, comprising a sensor module 1, a control module 2 and an execution module 3, wherein the output end of the sensor module 1 is connected to the input end of the control module 2, and the output end of the control module 2 is connected to the input end of the execution module 3. The sensor module 1 inputs battery temperature information and evaporator temperature information to the control module 2, and the control module 2 outputs control instructions to the execution module 3.

[0032] The sensor module 1 includes a battery temperature sensor and an evaporator temperature sensor, and the output end of the battery temperature sensor and the output end of the evaporator temperature sensor are respectively connected to the input end of the control module 2. The control module 2 adopts a microcontroller. The execution module 3 includes a refrigerant stop valve and a compressor, and the output end of the control module 2 is respectively connected to the input end of the refrigerant stop valve and the input end of the compressor.

[0033] The present invention provides a control method for an automobile thermal management system:

[0034] After the car is powered on, the refrigerant stop valve is in a closed state, and the battery temperature sensor and the evaporator temperature sensor respectively collect the temperature information of the battery and the temperature information of the evaporator and input them into the control module 2; when the evaporator temperature is greater than the evaporator target temperature and the battery temperature is less than or equal to the first target temperature of the battery, the control module 2 controls the refrigerant stop valve to maintain a closed state; when the evaporator temperature is less than or equal to the evaporator target temperature and the battery temperature is less than or equal to the first target temperature of the battery, the control module 2 controls the refrigerant stop valve to open; when the evaporator temperature is less than or equal to the evaporator target temperature and the battery temperature is greater than the first target temperature of the battery, the control module 2 controls the refrigerant stop valve to open; when the evaporator temperature is greater than the evaporator target temperature and the battery temperature is greater than the first target temperature of the battery, the control module 2 controls the refrigerant temperature stop valve to open and increases the working power of the compressor.

[0035] After the refrigerant stop valve is opened, when the battery temperature is lower than the second target battery temperature, the evaporator temperature is higher than the evaporator target temperature, and the evaporator rise temperature exceeds the first calibration value, the control module 2 controls the refrigerant stop valve to close. The first calibration value is the difference between the actual evaporator temperature and the evaporator temperature when the refrigerant stop valve was last opened.

[0036] After the refrigerant stop valve is opened and then closed, when the evaporator temperature drops to more than the second calibration value, the control module 2 controls the refrigerant stop valve to open again. The second calibration value is the difference between the actual evaporator temperature and the evaporator temperature when the refrigerant stop valve was last closed.

[0037] The following describes in detail an automobile thermal management system and a control method thereof according to the present invention.

[0038] An automobile thermal management system of the present invention comprises a sensor module 1, a control module 2 and an execution module 3, wherein the sensor module 1 comprises a battery temperature sensor and an evaporator temperature sensor, the battery temperature sensor is used to detect the temperature of the automobile battery, and the evaporator sensor is used to detect the temperature of the evaporator, and the temperature of the evaporator can reflect the cooling demand of the cockpit; the battery temperature sensor and the evaporator temperature sensor input the collected temperature information of the automobile battery and the evaporator into the control module 2.

[0039] The control module 2 uses a microcontroller, which is used to receive the temperature information of the car battery and the evaporator input by the sensor module 1 and issue control instructions to control the operation of the execution module 3. The microcontroller in the present invention uses a model of Traveo TM Microcontrollers from T2Gmicrocontrollers.

[0040] The execution module 3 uses a refrigerant stop valve and a compressor. The refrigerant stop valve is used to control the circulation of the refrigerant to adjust the temperature in the car cockpit and the temperature of the car battery. The compressor is used to compress the low-pressure gas into high-pressure gas. In the present invention, the control module 2 controls the power of the compressor to meet the cooling requirements of the car cockpit and the car battery. The present invention solves the cooling requirements of the cockpit and the battery only through the cooperation of a refrigerant stop valve and a compressor, reduces costs, and reduces the probability of failure.

[0041] according to Figure 2 Describe the working principle of the thermal management system. The refrigerant is compressed by the compressor and then enters the condenser. When the refrigerant shut-off valve is closed, the refrigerant only flows through the evaporator, and the thermal management system only cools down the cockpit. When the refrigerant shut-off valve is opened, the refrigerant is condensed by the condenser and then flows through the evaporator and the battery heat exchanger connected in series with the battery shut-off valve. The refrigerant throttles, expands, evaporates and absorbs heat in the battery heat exchanger, and the battery coolant absorbs heat in the battery heat exchanger. The battery coolant that absorbs heat cools the battery. At this time, the thermal management system adjusts the temperature of the cockpit and the battery at the same time. When the temperature in the cockpit and the battery temperature are both high, the thermal management system increases the power of the compressor to achieve the purpose of lowering the temperature of the cockpit and the battery.

[0042] The following is a detailed description of a control method for an automobile thermal management system of the present invention.

[0043] When the car is powered on, the refrigerant stop valve is closed, the compressor starts working, and the refrigerant flows through the evaporator circuit to reduce the temperature in the cockpit. The evaporator temperature sensor and the battery temperature sensor respectively collect the evaporator temperature and battery temperature information and input them into the control module 2.

[0044] When the evaporator temperature is greater than the evaporator target temperature and the battery temperature is less than or equal to the battery first target temperature, the cockpit cooling demand is high and the battery cooling demand is not high. The control module 2 controls the refrigerant shut-off valve to maintain a closed state, and the refrigerant only flows through the evaporator. The temperature of the cockpit can be effectively reduced.

[0045] When the evaporator temperature is less than or equal to the evaporator target temperature and the battery temperature is less than or equal to the first target battery temperature, the cooling demand of the cockpit is not high and the cooling demand of the battery is not high. The control module 2 controls the refrigerant shut-off valve to open, and the refrigerant uses the excess cold to reduce the temperature of the battery coolant, thereby helping the battery maintain a suitable temperature. The energy is reused, reducing the energy loss of the system.

[0046] When the evaporator temperature is less than or equal to the evaporator target temperature and the battery temperature is greater than the first target battery temperature, the cooling demand of the cockpit is not high, but the battery cooling demand is high. The control module 2 controls the refrigerant shut-off valve to open, and the refrigerant throttles, expands, evaporates and absorbs heat in the battery heat exchanger, absorbing the heat of the battery coolant. The battery coolant that absorbs heat cools the battery.

[0047] When the evaporator temperature is greater than the evaporator target temperature and the battery temperature is greater than the battery first target temperature, the cockpit cooling demand is high and the battery cooling demand is high. The control module 2 controls the refrigerant shut-off valve to open and increases the working power of the compressor. It can also increase the compressor displacement to achieve the purpose of improving the refrigeration effect, reduce the temperature in the cockpit and reduce the battery temperature, protect the safety of the battery, and adjust the temperature in the cockpit.

[0048] In an embodiment of the present invention, the first target temperature of the battery is 43°C, and the target temperature of the evaporator is 5°C.

[0049] After the refrigerant stop valve is opened, when the battery temperature is less than the second target temperature of the battery, the evaporator temperature is greater than the evaporator target temperature, and the evaporator rising temperature exceeds the first calibration value, the control module 2 controls the refrigerant stop valve to close. At this time, the temperature in the cockpit rises too fast, and the battery temperature is appropriate. The cockpit temperature is adjusted by closing the refrigerant stop valve to prevent the cockpit temperature from rising too fast. The first calibration value is the difference between the actual evaporator temperature and the evaporator temperature when the refrigerant stop valve was last opened. In the embodiment of the present invention, the second target temperature of the battery is 41°C, and the first calibration value is 5°C. After the refrigerant stop valve is opened and closed again, when the evaporator temperature drops more than the second calibration value, the control module 2 controls the refrigerant stop valve to open again. At this time, the cockpit temperature drops faster due to the closure of the refrigerant stop valve, and the excess cold is allocated to the battery coolant by opening the refrigerant stop valve. The second calibration value is the difference between the actual evaporator temperature and the evaporator temperature when the refrigerant stop valve was last closed. In the embodiment of the present invention, the second calibration value is 3°C. Under the premise of protecting the safety of the battery, the present invention reduces the fluctuation of the temperature in the cockpit and improves the comfort of the driver.

[0050] The present invention takes into account the cooling requirements of the cockpit and the battery, realizes cooling capacity distribution by accurately controlling the opening and closing of the refrigerant stop valve, and solves the cooling requirements of the cockpit and the battery.

[0051] The present invention is described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention; or the above concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. An automotive thermal management system, characterized in that: It comprises a sensor module, a control module and an execution module, wherein the output end of the sensor module is connected to the input end of the control module, and the output end of the control module is connected to the input end of the execution module.

2. An automotive thermal management system according to claim 1, characterized in that: The sensor module inputs battery temperature information and evaporator temperature information to the control module, and the control module outputs control instructions to the execution module.

3. The automotive thermal management system according to claim 1, characterized in that: The sensor module comprises a battery temperature sensor and an evaporator temperature sensor, and the output end of the battery temperature sensor and the output end of the evaporator temperature sensor are respectively connected to the input end of the control module.

4. The automotive thermal management system according to claim 1, characterized in that: The control module adopts a microcontroller.

5. The automotive thermal management system according to claim 1, characterized in that: The execution module includes a refrigerant stop valve and a compressor, and the output end of the control module is connected to the input end of the refrigerant stop valve and the input end of the compressor respectively.

6. A control method for an automotive thermal management system according to any one of claims 1 to 5, characterized in that: After the car is powered on, the refrigerant shut-off valve is closed, and the battery temperature sensor and the evaporator temperature sensor respectively collect the temperature information of the battery and the temperature information of the evaporator and input them into the control module; When the evaporator temperature is greater than the evaporator target temperature and the battery temperature is less than or equal to the first battery target temperature, the control module controls the refrigerant stop valve to maintain a closed state; When the evaporator temperature is less than or equal to the evaporator target temperature and the battery temperature is less than or equal to the first battery target temperature, the control module controls the refrigerant stop valve to open; When the evaporator temperature is less than or equal to the evaporator target temperature and the battery temperature is greater than the first target battery temperature, the control module controls the refrigerant stop valve to open; When the evaporator temperature is greater than the evaporator target temperature and the battery temperature is greater than the first target battery temperature, the control module controls the refrigerant temperature cut-off valve to open and increases the operating power of the compressor.

7. A control method for an automotive thermal management system as claimed in claim 6, characterized in that: After the refrigerant stop valve is opened, when the battery temperature is lower than the second target battery temperature, the evaporator temperature is higher than the evaporator target temperature, and the evaporator rise temperature exceeds the first calibration value, the control module controls the refrigerant stop valve to close.

8. A control method for an automotive thermal management system as claimed in claim 7, characterized in that: The first calibration value is the difference between the actual evaporator temperature and the evaporator temperature when the refrigerant stop valve was last opened.

9. A control method for an automotive thermal management system as claimed in claim 7, characterized in that: After the refrigerant stop valve is opened and then closed, when the evaporator temperature drops to exceed the second calibration value, the control module controls the refrigerant stop valve to open again.

10. A control method for an automotive thermal management system as claimed in claim 9, characterized in that: The second calibration value is the difference between the actual evaporator temperature and the evaporator temperature when the refrigerant stop valve was last closed.

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