Impurity filter, new energy automobile thermal management system and system control method

Abstract

The invention provides an impurity filter which comprises a filter connecting block, a filter screen arranged in the filter connecting block and two pressing blocks fixedly connected to the two ends of the filter connecting block respectively, a through hole is formed in the filter connecting block, and pipeline connecting openings are formed in the positions, corresponding to the through hole, of the pressing blocks. A refrigerant circulation pipeline is fixed to the pipeline connector, the structure is simple, manufacturing is easy, cost is low, and disassembly and assembly are convenient. The invention further provides a new energy automobile heat management system and a system control method, the system comprises a refrigerant circulation loop, a first filtering branch, a second filtering branch and a controller, impurity filters in the first filtering branch and the second filtering branch are connected into the refrigerant circulation loop in parallel through a three-way valve, and the adverse effect on the refrigerant circulation loop can be reduced; the controller controls the new energy automobile thermal management system to operate in a self-cleaning mode or a thermal management working mode; the supercooling degree / superheat degree is obtained by detecting the temperature and the pressure, and the impurity content in the refrigerant can be judged more accurately.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal management systems for new energy vehicles, and in particular to an impurity filter, a thermal management system for new energy vehicles, and a system control method. Background Art

[0002] Automobile thermal management systems usually include heat exchangers, compressors, expansion valves, chillers, pipes and other parts. Usually, these parts (especially heat exchangers and compressors) are prone to produce impurities such as iron filings and aluminum filings during production, installation and operation. During the operation of the thermal management system, these impurities are likely to damage the expansion valve, causing leakage of the expansion valve, or uncontrolled refrigerant flow. In severe cases, the throttle port is blocked, and the system pressure is abnormal, causing a fault and shutdown. At the same time, it may also damage the compressor, causing cylinder scuffing, or damage other parts in the system, which will lead to performance degradation or even failure of the thermal management system.

[0003] Currently, most existing impurity filtering solutions involve retrofitting filters on the original gas-liquid separator and other component structures, or adding an impurity filtering pipeline consisting of multiple two-way valves to the original refrigerant circulation loop, and installing filters inside the pipeline to filter impurities. Such a structure not only greatly increases the cost and difficulty of equipment processing and manufacturing, but also directly setting up a filtering structure in the original circulation loop will increase the flow resistance in the pipeline when the system is working normally and reduce system performance; when the filter is blocked, it is also difficult to repair and replace, which in turn affects the normal operation of the thermal management system.

[0004] In addition, in the existing thermal management system control scheme, the impurity content in the refrigerant fluid is judged only by monitoring the pressure before and after the valve in the system pipeline. This judgment method has poor accuracy and is prone to misjudgment. Summary of the invention

[0005] The present invention is made to solve the above-mentioned problems, and aims to provide a low-cost, easy-to-maintain impurity filter and a new energy vehicle thermal management system, as well as an accurate and efficient system control method.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] An impurity filter is provided in a thermal management system of a new energy vehicle, comprising a filter connection block, a filter screen provided inside the filter connection block, and two pressing blocks respectively fastened to both ends of the filter connection block, wherein:

[0008] A through hole is provided on the filter connection block, and the channel of the through hole includes an inlet section, a filter section, a connection section and an outlet section connected in sequence.

[0009] The diameter of the connecting section is smaller than the diameter of the filtering section. A step is formed at the junction of the connecting section and the filtering section. The edge of the filter is located in the filtering section and one side abuts against the step.

[0010] A pipe connection port is provided on the pressing block at a position corresponding to the through hole, and a refrigerant flow pipe is fixed on the pipe connection port.

[0011] The two pressing blocks are respectively located at two ends of the through hole, and the ends of the refrigerant flow pipe connected to the two pressing blocks are respectively located in the inlet section and the outlet section of the through hole.

[0012] Furthermore, the filter includes a mounting ring and a filter body, the outer edge of the mounting ring is interference fit with the inner wall of the through hole filter section on the filter connection block, and the edge of the filter body is fixed on the mounting ring and is in a bag shape concave toward the connection section.

[0013] Furthermore, a sealing ring is provided on the end of the refrigerant circulation pipe located in the through hole.

[0014] Furthermore, a bolt mounting hole is provided on the pressing block, and a threaded connection hole consistent with the length direction of the through hole is provided at a corresponding position on the filtering connecting block. The pressing block and the filtering connecting block are fastened and connected by bolts matching the bolt mounting hole and the threaded connection hole.

[0015] A new energy vehicle thermal management system includes a refrigerant circulation loop, a first filter branch, a second filter branch, and a controller, wherein:

[0016] The refrigerant circulation loop includes a compressor, an indoor condenser, a first expansion valve, an outdoor heat exchanger, a solenoid valve, a second expansion valve, a chiller, a third expansion valve, an indoor evaporator, and a gas-liquid separator connected by pipelines;

[0017] The first filter branch includes a first three-way valve and a first filter connected by a pipeline;

[0018] The second filter branch includes a second three-way valve and a second filter connected by a pipeline.

[0019] The controller is electrically connected to the compressor, the first expansion valve, the solenoid valve, the second expansion valve, the third expansion valve, the gas-liquid separator, the first three-way valve and the second three-way valve, and is used to control the new energy vehicle thermal management system to operate in a self-cleaning mode or a thermal management working mode.

[0020] The first three-way valve and the second three-way valve each include three valve ports a, b, and c.

[0021] The exhaust port of the compressor is connected to the inlet of the indoor condenser, the outlet of the indoor condenser is connected to the port a of the first three-way valve, the port c of the first three-way valve is connected to the inlet of the first expansion valve, the outlet of the first expansion valve is connected to the inlet of the outdoor heat exchanger, the outlet of the outdoor heat exchanger is connected to the inlet of the solenoid valve, the outlet of the solenoid valve is connected to the port a of the second three-way valve, the port c of the second three-way valve is connected to the inlet of the gas-liquid separator, and the outlet of the gas-liquid separator is connected to the air intake port of the compressor;

[0022] The outlet of the outdoor heat exchanger is also connected to the inlet of the second expansion valve, the outlet of the second expansion valve is connected to the inlet of the Chiller, and the outlet of the Chiller is connected to the port a of the second three-way valve;

[0023] The outdoor heat exchanger outlet is also connected to the third expansion valve inlet, the third expansion valve outlet is connected to the indoor evaporator inlet, and the indoor evaporator outlet is connected to the a port of the second three-way valve;

[0024] The inlet of the first filter is connected to the port b of the first three-way valve, and the outlet of the first filter is connected between the port c of the first three-way valve and the inlet of the first expansion valve;

[0025] The inlet of the second filter is connected to the port b of the second three-way valve, and the outlet of the second filter is connected between the port c of the second three-way valve and the inlet of the gas-liquid separator.

[0026] The first filter and the second filter are the above-mentioned impurity filters.

[0027] Furthermore, a first pressure sensor is connected to the pipe at the outlet of the first filter; a second pressure sensor is connected to the pipe at the outlet of the second filter.

[0028] The first pressure sensor and the second pressure sensor are electrically connected to the controller respectively and are used to detect the pressure in the pipeline.

[0029] Furthermore, a first pressure and temperature sensor is provided on the pipe at the indoor condenser outlet; a second pressure and temperature sensor is provided on the pipe at the outdoor heat exchanger outlet; the pipe connecting the indoor evaporator outlet merges with the pipe connecting the chiller outlet, and a third pressure and temperature sensor is provided on the merged confluence pipe; a fourth pressure and temperature sensor is provided on the pipe at the compressor outlet; and a fifth pressure and temperature sensor is provided on the pipe at the gas-liquid separator outlet.

[0030] The first pressure and temperature sensor, the second pressure and temperature sensor, the third pressure and temperature sensor, the fourth pressure and temperature sensor, and the fifth pressure and temperature sensor are all electrically connected to the controller and are used to measure the pressure and temperature in the corresponding pipelines.

[0031] A control method for a new energy vehicle thermal management system is provided, based on the above-mentioned new energy vehicle thermal management system:

[0032] When the new energy vehicle thermal management system is powered on and started, the controller determines whether this operation is the first operation. If the judgment result is yes, the new energy vehicle thermal management system enters the self-cleaning mode;

[0033] When the new energy vehicle thermal management system is powered on and started, the controller receives an external instruction to set the operation mode to the cleaning mode, and the new energy vehicle thermal management system enters the self-cleaning mode;

[0034] After the new energy vehicle thermal management system is powered on and started, the controller receives an external instruction to set the operation mode to the thermal management working mode, and the new energy vehicle thermal management system enters the thermal management working mode; during the operation of the new energy vehicle thermal management system in the thermal management working mode, the controller controls the first to fifth pressure and temperature sensors to respectively detect the pressure and temperature at various locations in the circuit in real time, and obtains the supercooling or superheating of the refrigerant at the corresponding position. When the opening degree of any one of the first to third expansion valves under the current working condition reaches the extreme value under the working condition, the controller further determines whether the supercooling or superheating at at least one of the two positions corresponding to the first pressure and temperature sensor and the third pressure and temperature sensor exceeds the corresponding threshold value, and obtains a judgment result A; the controller further determines whether the pressure at at least one of the two positions corresponding to the fourth pressure and temperature sensor and the fifth pressure and temperature sensor reaches the corresponding threshold value, and obtains a judgment result B; if at least one of the judgment result A or the judgment result B is "yes", the new energy vehicle thermal management system enters the self-cleaning mode under the control of the controller; if both the judgment result A and the judgment result B are "no", the new energy vehicle thermal management system continues to operate in the thermal management working mode.

[0035] Furthermore, the process of automatically operating the new energy vehicle thermal management system in the self-cleaning mode under the control of the controller includes the following steps:

[0036] Step S1: The first pressure sensor and the second pressure sensor respectively detect the pressure at the outlet of the first filter block and the second filter block in real time to obtain the first filter pressure and the second filter pressure, and further determine whether at least one of the first filter pressure and the second filter pressure is lower than the filter pressure threshold. If the determination result is "yes", the cleaning mode operation ends; if the determination result is "no", the operation continues in the cleaning mode;

[0037] Step S2: The compressor is turned on to the maximum speed, ports a and b in the first three-way valve and the second three-way valve are all opened, port c is closed, the first expansion valve is fully opened, the solenoid valve is opened, and the second expansion valve and the third expansion valve are closed;

[0038] Step S3: the compressor is kept running at the maximum speed, the solenoid valve is closed, and the third expansion valve is opened;

[0039] Step S4: the compressor is kept running at the maximum speed, the third expansion valve is closed, and the second expansion valve is opened;

[0040] Step S5: Repeat steps S1-S4 for several times. Finally, open the port c of the first three-way valve and the second three-way valve and close the port b, and the self-cleaning mode ends.

[0041] Preferably, the supercooling threshold is 5° C., the superheating threshold is 10° C., the filtering pressure threshold is 14 barA, and the number of cycles in step S5 is 3 to 5 times.

[0042] The present invention has the following beneficial effects:

[0043] 1. The impurity filter provided by the present invention can filter impurities generated in the thermal management system of new energy vehicles, protect the components in the thermal management system, and improve the operating efficiency of the thermal management system; the impurity filter has a simple overall structure, does not require modification of other original components, is easy to manufacture, and has low cost; when replacing a clogged filter, the filter connection block can be directly removed together with the internal filter, and then the filter connection block equipped with a clean filter can be tightly connected to the pressing block, which is simple and quick to operate.

[0044] 2. The new energy vehicle thermal management system provided by the present invention sets the installation positions of the first filter and the second filter (impurity filter) according to the main sources of impurities and the objects to be protected, which can maximize the effect of removing impurities and protecting components; the impurity filter is connected in parallel to the refrigerant circulation loop through a three-way valve, so that the first and second filter branches are relatively independent of the refrigerant circulation loop, which can reduce the adverse effects on the refrigerant circulation loop, and has low cost and is easy to maintain. The first and second filter branches are only opened when the system is running in self-cleaning mode. When the system is operating normally in thermal management working mode, the filter branch can be closed through the three-way valve to avoid the existence of the filter affecting the flow resistance of the refrigerant circulation loop, effectively improving system performance.

[0045] 3. The control method of the new energy vehicle thermal management system provided by the present invention obtains subcooling and superheating by using pressure and temperature sensors to collect pressure and temperature data, which can more accurately judge the impurity content of the refrigerant fluid in the pipeline, thereby more accurately grasping the appropriate time to start the self-cleaning mode, making the system operation more stable and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 is an exploded view of the impurity filter in Example 1 of the present invention;

[0047] Figure 2 is a cross-sectional view of the filter screen and the filter connecting block in Example 1 of the present invention;

[0048] Figure 3 is a connection diagram of an automobile thermal management system in Embodiment 2 of the present invention;

[0049] Figure 4 This is a flow chart of the self-cleaning mode operation in Example 3 of the present invention.

[0050] Figure Number:

[0051] 11-filter connection block, 111-through hole, 111a-inlet section, 111b-filter section, 111c-connection section, 111d-outlet section, 112-step, 12-filter screen, 121-mounting ring, 122 filter screen body, 13-pressing block, 131-pipe connection port, 132-bolt mounting hole, 14-refrigerant circulation pipeline, 15-threaded connection hole, 16-bolt, 17-sealing ring;

[0052] 21-first three-way valve, 22-first filter, 23-second three-way valve, 24-second filter, 25-first pressure sensor, 26-second pressure sensor;

[0053] 30-gas-liquid separator, 31-compressor, 32-indoor condenser, 33-first expansion valve, 34-outdoor heat exchanger, 35-solenoid valve, 36-second expansion valve, 37-Chiller, 38-third expansion valve, 39-indoor evaporator;

[0054] 41 - a first pressure and temperature sensor, 42 - a second pressure and temperature sensor, 43 - a third pressure and temperature sensor, 44 - a fourth pressure and temperature sensor, 45 - a fifth pressure and temperature sensor. DETAILED DESCRIPTION

[0055] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the following embodiments are combined with the accompanying drawings to specifically explain the impurity filter, new energy vehicle thermal management system and system control method of the present invention.

[0056] <Example 1>

[0057] like Figure 1 , 2 As shown, an impurity filter of this embodiment is arranged in a thermal management system of a new energy vehicle, comprising a filter connection block 11, a filter screen 12 arranged inside the filter connection block 11, and two pressing blocks 13 ( Figure 1 The pressing block at one end is not shown), wherein:

[0058] A through hole 111 is formed on the filter connection block 11 , and the through hole 111 includes an inlet section 111 a , a filter section 111 b , a connection section 111 c and an outlet section 111 d which are connected in sequence.

[0059] The diameter of the connecting section 111c is smaller than the diameter of the filtering section 111b. A step 112 is formed at the junction of the connecting section 111c and the filtering section 111b. The edge of the filter screen 12 is located in the filtering section 111b and one side is against the step 112, which can improve the stability of the filter screen 12 and avoid shaking due to the flushing of the refrigerant fluid.

[0060] A pipe connection port 131 is formed on the pressing block 13 at a position corresponding to the through hole 111 , and a refrigerant flow pipe 14 is fixed to the pipe connection port 131 .

[0061] In this embodiment, the diameters of the inlet section 111a and the outlet section 111d are both compatible with the refrigerant circulation pipe 14, and the diameter of the inlet section 111a is not less than the diameter of the filter section 111b, so that the filter can be easily installed in the through hole 111.

[0062] The two pressing blocks 13 are respectively located at the two ends of the through hole 111 , and the ends of the refrigerant circulation pipe 14 connected to the two pressing blocks 13 are respectively located in the inlet section 111a and the outlet section 111d of the through hole 111 , so that the refrigerant fluid can pass through the through hole 111 and be filtered by the filter 12 .

[0063] Furthermore, the filter 12 includes a mounting ring 121 and a filter body 122, and the outer edge of the mounting ring 121 is interference fit with the inner wall of the through hole filter section 111b on the filter connection block 11. In this embodiment, the mounting ring 121 is made of copper, the filter body 122 is made of stainless steel, and the filter connection block 11 is made of aluminum. The edge of the filter body 122 is fixed on the mounting ring 121 and is in a bag shape that is concave toward the connection section 111c, with a larger filtering area, which can achieve a better filtering effect.

[0064] Furthermore, a sealing ring 17 is provided on the end of the refrigerant flow pipe 14 located in the through hole 111 to prevent refrigerant leakage. In this embodiment, the refrigerant flow pipe 14 and the pressing block 13 are fixedly connected by welding, and the overall structure is more firm and stable.

[0065] Furthermore, a bolt mounting hole 132 is provided on the pressing block 13, and a threaded connection hole 15 which is consistent with the length direction of the through hole 111 is provided at a corresponding position on the filter connection block 11. The pressing block 13 and the filter connection block 11 are fastened and connected by bolts 16 which are matched with the bolt mounting hole 132 and the threaded connection hole 15, so that the disassembly and assembly are simpler and more convenient, and easy to replace and maintain. In this embodiment, the threaded connection hole 15 is a blind hole, and the bolt mounting hole 132 is a countersunk hole. The head end of the bolt 16 is located in the bolt mounting hole 132, and the tail end passes through the bolt mounting hole 132 and is screwed into the threaded connection hole 15.

[0066] During filtering, the refrigerant fluid flows into the through hole 111 of the filter connecting block 11 from the refrigerant circulation pipe 14 near the inlet section 111a. When passing through the filter section 111b and the connecting section 111c, the impurities in the refrigerant fluid are filtered by the filter screen 12. The filtered refrigerant fluid continues to flow through the outlet section 111d and finally flows out of the filter connecting block 11 through the refrigerant circulation pipe 14 connected to the corresponding side pressure block 13, completing the filtering.

[0067] When the filter screen 12 is clogged by impurities and needs to be replaced, first unscrew the bolts at both ends of the filter connection block 11, remove the filter connection block 11 together with the filter screen inside from between the two pressing blocks 13, and then re-tighten the two pressing blocks 13 to the filter connection block 11 equipped with a clean filter screen 12 through bolts. The removed filter connection block 11 and the clogged filter screen 12 inside can be recycled and cleaned for reuse, which saves costs; the filter connection block 11 and the pressing block 13 are connected by bolts, with a simple structure and easy disassembly and assembly; the filter screen 12 does not need to be removed from the filter connection block 11, and the filter screen 12 and the filter connection block 11 are disassembled and replaced together as a fixedly connected whole, which is simpler and faster.

[0068] <Example 2>

[0069] This embodiment provides a new energy vehicle thermal management system, including a refrigerant circulation loop, a first filter branch, a second filter branch, and a controller, wherein:

[0070] like Figure 3 As shown, the refrigerant circulation loop includes a compressor 31, an indoor condenser 32, a first expansion valve 33, an outdoor heat exchanger 34, a solenoid valve 35, a second expansion valve 36, a Chiller 37, a third expansion valve 38, an indoor evaporator 39, and a gas-liquid separator 30 connected by pipelines.

[0071] The first filtering branch includes a first three-way valve 21 and a first filter 22 connected by a pipeline.

[0072] The second filtering branch includes a second three-way valve 23 and a second filter 24 connected by a pipeline.

[0073] The controller is electrically connected to the compressor 31, the first expansion valve 33, the solenoid valve 35, the second expansion valve 36, the third expansion valve 38, the gas-liquid separator 30, the first three-way valve 21 and the second three-way valve 23, and can control the new energy vehicle thermal management system to operate in self-cleaning mode or thermal management working mode.

[0074] The first three-way valve 21 and the second three-way valve 23 each include three valve ports a, b, and c.

[0075] The exhaust port of the compressor 31 is connected to the inlet of the indoor condenser 32, the outlet of the indoor condenser 32 is connected to the port a of the first three-way valve 21, the port c of the first three-way valve 21 is connected to the inlet of the first expansion valve 33, and the outlet of the first expansion valve 33 is connected to the inlet of the outdoor heat exchanger 34.

[0076] The outlet of the outdoor heat exchanger 34 is connected to the inlet of the solenoid valve 35, the outlet of the solenoid valve 35 is connected to the port a of the second three-way valve 23, the port c of the second three-way valve 23 is connected to the inlet of the gas-liquid separator 30, and the outlet of the gas-liquid separator 30 is connected to the suction port of the compressor 31.

[0077] The outlet of the outdoor heat exchanger 34 is also connected to the inlet of the second expansion valve 36 , the outlet of the second expansion valve 36 is connected to the inlet of Chiller 37 , and the outlet of Chiller 37 is connected to the port a of the second three-way valve 23 .

[0078] The outlet of the outdoor heat exchanger 34 is also connected to the inlet of the third expansion valve 38 , the outlet of the third expansion valve 38 is connected to the inlet of the indoor evaporator 39 , and the outlet of the indoor evaporator 39 is connected to the port a of the second three-way valve 23 .

[0079] By controlling the opening and closing of the solenoid valve 35, the second expansion valve 36 and the third expansion valve 38, the flow direction of the refrigerant in the pipeline can be switched so that the refrigerant flows along different paths.

[0080] The inlet of the first filter 22 is connected to the port b of the first three-way valve 21, and the outlet of the first filter 22 is connected between the port c of the first three-way valve 21 and the inlet of the first expansion valve 33, so that the first filter branch is connected to the refrigerant circulation loop. The first filter branch can remove impurities from the indoor condenser 32 and the compressor 31 to protect the first expansion valve 33.

[0081] The inlet of the second filter 24 is connected to the port b of the second three-way valve 23, and the outlet of the second filter 24 is connected between the port c of the second three-way valve 23 and the inlet of the gas-liquid separator 30, so that the second filter branch is connected to the refrigerant circulation loop. The second filter branch can filter impurities from the outdoor heat exchanger 34, the indoor evaporator 39, and the Chiller 37 to protect the second expansion valve 36, the third expansion valve 38 and the compressor 31.

[0082] In the new energy vehicle thermal management system of this embodiment, the first filter 22 and the second filter 24 are both the impurity filters of Embodiment 1.

[0083] When the thermal management system of a new energy vehicle is in thermal management working mode, the system works normally, and the refrigerant fluid in the pipeline flows in the refrigerant circulation loop. The refrigerant fluid absorbs and releases heat to achieve temperature regulation of the vehicle air conditioning system, battery system and other structures, thereby achieving the effect of thermal management. When the thermal management system of a new energy vehicle is in self-cleaning mode, the refrigerant fluid is passed into the first and second filter branches, and filtered through the filter 12 to achieve the purpose of self-cleaning. The controller controls the opening and closing of each valve port in the first three-way valve 21 and the second three-way valve 23, so that the refrigerant flows along the original refrigerant circulation loop or flows into the first and second filter branches, thereby achieving the switching between the thermal management working mode and the self-cleaning mode.

[0084] The structure, connection relationship, and working method of each component in the refrigerant circulation circuit of this embodiment are similar to the refrigerant (refrigerant) circulation circuit of the existing automobile thermal management system. In actual application, the refrigerant circulation circuit can be set as needed, and the air flow is provided for the heat exchange between the refrigerant of the heat exchanger and the surrounding air through fans, blowers and other components. The focus of the present invention is not on the refrigerant circulation circuit, but on the structure of the first and second filters (impurity filters), the setting position of the first and second filter branches and the way of connecting to the refrigerant circulation circuit, and the process of system self-cleaning. Therefore, in this embodiment, the structure that is the same as that of the existing thermal management system and the specific working process of the refrigerant circulation circuit under the thermal management working mode are not repeated.

[0085] Furthermore, a first pressure sensor 25 is connected to the pipe at the outlet of the first filter 22; a second pressure sensor 26 is connected to the pipe at the outlet of the second filter 24. The first pressure sensor 25 and the second pressure sensor 26 are electrically connected to the controller respectively, and can detect the pressure in the pipe. The refrigerant flow after passing through the filter can be known through the pressure data, which reflects the degree of blockage of the filter 12 and provides a basis for judging whether to replace the filter.

[0086] Furthermore, a first pressure-temperature sensor 41 is provided on the pipe at the outlet of the indoor condenser 32; a second pressure-temperature sensor 42 is provided on the pipe at the outlet of the outdoor heat exchanger 34; the pipe connected to the outlet of the indoor evaporator 39 merges with the pipe connected to the outlet of the Chiller 37, and a third pressure-temperature sensor 43 is provided on the merged pipe; a fourth pressure-temperature sensor 44 is provided on the pipe at the outlet of the compressor 31; and a fifth pressure-temperature sensor 45 is provided on the pipe at the outlet of the gas-liquid separator 30.

[0087] The first pressure and temperature sensor 41, the second pressure and temperature sensor 42, the third pressure and temperature sensor 43, the fourth pressure and temperature sensor 44 and the fifth pressure and temperature sensor 45 are all electrically connected to the controller, and can measure the pressure and temperature in the corresponding pipelines, providing a basis for judging whether the refrigerant fluid needs to be cleaned.

[0088] <Example 3>

[0089] This embodiment provides a control method for a new energy vehicle thermal management system, which is based on the new energy vehicle thermal management system of Embodiment 2:

[0090] When the new energy vehicle thermal management system is powered on and started, the controller determines whether this operation is the first operation. If the judgment result is yes, the new energy vehicle thermal management system enters the self-cleaning mode.

[0091] When the thermal management system of the new energy vehicle is powered on and started, the controller receives an external instruction to set the operating mode to the cleaning mode, and the thermal management system of the new energy vehicle enters the self-cleaning mode.

[0092] When the thermal management system of the new energy vehicle is powered on and started, the controller receives an external instruction to set the operation mode to the thermal management working mode, and the thermal management system of the new energy vehicle enters the thermal management working mode.

[0093] During the operation of the new energy vehicle thermal management system in the thermal management working mode, the controller controls the first to fifth pressure and temperature sensors 45 to respectively detect the pressure and temperature at each position in the circuit in real time, and obtains the supercooling or superheating of the refrigerant at the corresponding position. When the opening degree of any one of the first to third expansion valves reaches the extreme value under the current working condition, the controller further determines whether the supercooling or superheating at at least one of the two positions corresponding to the first pressure and temperature sensor 41 and the third pressure and temperature sensor 43 exceeds the corresponding threshold value, and obtains the judgment result A; the controller further determines whether the pressure at at least one of the two positions corresponding to the fourth pressure and temperature sensor 44 and the fifth pressure and temperature sensor 45 reaches the corresponding threshold value, and obtains the judgment result B. If at least one of the judgment result A or the judgment result B is "yes", the new energy vehicle thermal management system enters the self-cleaning mode under the control of the controller; if both the judgment result A and the judgment result B are "no", the new energy vehicle thermal management system continues to operate in the thermal management working mode.

[0094] Further, such as Figure 4 As shown, the process of the new energy vehicle thermal management system automatically running in the self-cleaning mode under the control of the controller includes the following steps:

[0095] Step S1: The first pressure sensor 25 and the second pressure sensor 26 respectively detect the pressures at the outlets of the first filter block and the second filter block in real time to obtain the first filter pressure and the second filter pressure, and further determine whether at least one of the first filter pressure and the second filter pressure is lower than the filter pressure threshold. If the determination result is "yes", the cleaning mode ends; if the determination result is "no", continue to operate in the cleaning mode and enter step S2.

[0096] If the measured first filter pressure or the second filter pressure is lower than the filter pressure threshold, it indicates that the filter 12 in the corresponding first filter branch or the second filter branch has been clogged. In practical applications, the controller can also be connected to a display screen or a speaker inside the car to issue a text or sound prompt when the filter needs to be replaced, reminding the driver to perform maintenance in time.

[0097] Step S2: The compressor 31 is turned on to the maximum speed, the ports a and b in the first three-way valve 21 and the second three-way valve 23 are all opened, the port c is closed, the first expansion valve 33 is fully opened, the solenoid valve 35 is opened, and the second expansion valve 36 and the third expansion valve 38 are closed.

[0098] At this time, the impurities generated by the gas-liquid separator 30, the compressor 31 and the indoor condenser 32 flow into the first filter branch along with the refrigerant fluid and are filtered by the first filter; while the impurities generated by the outdoor heat exchanger 34 flow into the second filter branch along with the refrigerant and are filtered by the second filter, thereby achieving the effect of protecting each expansion valve.

[0099] Step S3: The compressor 31 is kept running at the maximum speed, the solenoid valve 35 is closed, and the third expansion valve 38 is opened.

[0100] At this time, impurities generated at the indoor evaporator 39 flow into the second filter branch along with the refrigerant fluid and are filtered by the second filter, thereby achieving the effect of protecting the gas-liquid separator 30 and the compressor 31 .

[0101] Step S4: The compressor 31 is kept running at the maximum speed, the third expansion valve 38 is closed, and the second expansion valve 36 is opened.

[0102] At this time, the impurities generated at Chiller 37 flow into the second filter branch along with the refrigerant fluid and are filtered by the second filter, thereby achieving the effect of protecting the gas-liquid separator 30 and the compressor 31.

[0103] In practical applications, the order of step S3 and step S4 can be interchanged without affecting the cleaning effect.

[0104] Step S5: Repeat steps S1-S4 for several times. Finally, open the port c of the first three-way valve 21 and the second three-way valve 23 and close the port b, and the self-cleaning mode ends.

[0105] Closing the port b of the first, second and third-way valves can seal the filtered impurities between the filter screen 12 and the port b, preventing the impurities from flowing into the refrigerant circulation loop, thereby achieving a better cleaning effect. The solenoid valve 35, the first expansion valve 33, the second expansion valve 36 and the third expansion valve 38 are opened and closed according to the working conditions after entering the thermal management working mode.

[0106] Preferably, the supercooling threshold is 5° C., the superheating threshold is 10° C., the filtering pressure threshold is 14 barA, and the number of cycles in step S5 is 3 to 5 times.

[0107] The above-mentioned embodiments are preferred examples of the present invention and are not intended to limit the protection scope of the present invention.

Claims

1. An impurity filter, arranged in a thermal management system of a new energy vehicle, characterized in that: It comprises a filter connection block, a filter screen arranged inside the filter connection block, and two pressing blocks respectively fastened to two ends of the filter connection block, wherein: The filter connection block is provided with a through hole, and the through hole includes an inlet section, a filter section, a connection section and an outlet section connected in sequence. The diameter of the connecting section is smaller than the diameter of the filtering section. A step is formed at the junction of the connecting section and the filtering section. The edge of the filter screen is located in the filtering section and one side thereof abuts against the step. A pipe connection port is provided on the pressing block at a position corresponding to the through hole, and a refrigerant flow pipe is fixed on the pipe connection port. The two pressing blocks are respectively located at two ends of the through hole, and the ends of the refrigerant flow pipe connected to the two pressing blocks are respectively located in the inlet section and the outlet section of the through hole.

2. The impurity filter according to claim 1, characterized in that: in, The filter screen comprises a mounting ring and a filter screen body. The outer edge of the mounting ring is interference fit with the inner wall of the through hole filter section on the filter connection block. The edge of the filter screen body is fixed on the mounting ring and is in a bag shape concave toward the connection section.

3. The impurity filter according to claim 1, characterized in that: in, A sealing ring is provided on the end of the refrigerant flow pipe located in the through hole.

4. The impurity filter according to claim 1, characterized in that: in, The pressing block is provided with a bolt mounting hole, and a threaded connection hole consistent with the length direction of the through hole is provided at a corresponding position on the filtering connection block. The pressing block and the filtering connection block are fastened and connected by bolts matched with the bolt mounting hole and the threaded connection hole.

5. A new energy vehicle thermal management system, characterized in that: It includes a refrigerant circulation loop, a first filter branch, a second filter branch and a controller, wherein: The refrigerant circulation loop includes a compressor, an indoor condenser, a first expansion valve, an outdoor heat exchanger, a solenoid valve, a second expansion valve, a chiller, a third expansion valve, an indoor evaporator, and a gas-liquid separator connected by pipelines; The first filter branch includes a first three-way valve and a first filter connected by a pipeline; The second filter branch includes a second three-way valve and a second filter connected by a pipeline. The controller is electrically connected to the compressor, the first expansion valve, the solenoid valve, the second expansion valve, the third expansion valve, the gas-liquid separator, the first three-way valve and the second three-way valve, and is used to control the new energy vehicle thermal management system to operate in a self-cleaning mode or a thermal management working mode. The first three-way valve and the second three-way valve each include three valve ports a, b, and c. The exhaust port of the compressor is connected to the inlet of the indoor condenser, the outlet of the indoor condenser is connected to the port a of the first three-way valve, the port c of the first three-way valve is connected to the inlet of the first expansion valve, the outlet of the first expansion valve is connected to the inlet of the outdoor heat exchanger, the outlet of the outdoor heat exchanger is connected to the inlet of the solenoid valve, the outlet of the solenoid valve is connected to the port a of the second three-way valve, the port c of the second three-way valve is connected to the inlet of the gas-liquid separator, and the outlet of the gas-liquid separator is connected to the air intake port of the compressor; The outlet of the outdoor heat exchanger is also connected to the inlet of the second expansion valve, the outlet of the second expansion valve is connected to the inlet of the chiller, and the outlet of the chiller is connected to the port a of the second three-way valve; The outdoor heat exchanger outlet is also connected to the third expansion valve inlet, the third expansion valve outlet is connected to the indoor evaporator inlet, and the indoor evaporator outlet is connected to the a port of the second three-way valve; The inlet of the first filter is connected to the port b of the first three-way valve, and the outlet of the first filter is connected between the port c of the first three-way valve and the inlet of the first expansion valve; The inlet of the second filter is connected to the port b of the second three-way valve, and the outlet of the second filter is connected between the port c of the second three-way valve and the inlet of the gas-liquid separator. The first filter and the second filter are impurity filters as described in any one of claims 1 to 4.

6. The new energy vehicle thermal management system according to claim 5, characterized in that: in, A first pressure sensor is connected to the pipe at the outlet of the first filter; a second pressure sensor is connected to the pipe at the outlet of the second filter. The first pressure sensor and the second pressure sensor are electrically connected to the controller respectively, and are used to detect the pressure in the pipeline.

7. The new energy vehicle thermal management system according to claim 6, characterized in that: in, A first pressure and temperature sensor is provided on the pipe at the outlet of the indoor condenser; a second pressure and temperature sensor is provided on the pipe at the outlet of the outdoor heat exchanger; the pipe connected to the outlet of the indoor evaporator merges with the pipe connected to the outlet of the chiller, and a third pressure and temperature sensor is provided on the merged confluent pipe; a fourth pressure and temperature sensor is provided on the pipe at the outlet of the compressor; and a fifth pressure and temperature sensor is provided on the pipe at the outlet of the gas-liquid separator. The first pressure and temperature sensor, the second pressure and temperature sensor, the third pressure and temperature sensor, the fourth pressure and temperature sensor, and the fifth pressure and temperature sensor are all electrically connected to the controller and are used to measure the pressure and temperature in the corresponding pipelines.

8. A control method for a new energy vehicle thermal management system, based on the new energy vehicle thermal management system according to claim 7, characterized in that: After the new energy vehicle thermal management system is powered on and started, the controller determines whether this operation is the first operation. If the determination result is yes, the new energy vehicle thermal management system enters the self-cleaning mode; When the new energy vehicle thermal management system is powered on and started, the controller receives an external instruction to set the operation mode to the cleaning mode, and the new energy vehicle thermal management system enters the self-cleaning mode; After the new energy vehicle thermal management system is powered on and started, the controller receives an external instruction to set the operation mode to the thermal management working mode, and the new energy vehicle thermal management system enters the thermal management working mode; during the operation of the new energy vehicle thermal management system in the thermal management working mode, the controller controls the first to fifth pressure and temperature sensors to respectively detect the pressure and temperature at various locations in the circuit in real time, and obtains the supercooling or superheating of the refrigerant at the corresponding position. When the opening degree of any one of the first to third expansion valves under the current working condition reaches the extreme value under the working condition, the controller further determines whether the supercooling or superheating at at least one location of the two locations corresponding to the first pressure and temperature sensor and the third pressure and temperature sensor exceeds the corresponding threshold value, and obtains a judgment result A; the controller further determines whether the pressure at at least one location of the two locations corresponding to the fourth pressure and temperature sensor and the fifth pressure and temperature sensor reaches the corresponding threshold value, and obtains a judgment result B; if at least one of the judgment result A or the judgment result B is "yes", the new energy vehicle thermal management system enters the self-cleaning mode under the control of the controller; if both the judgment result A and the judgment result B are "no", the new energy vehicle thermal management system continues to operate in the thermal management working mode.

9. The control method of the thermal management system of a new energy vehicle according to claim 8, Features: in, The process of automatically operating the new energy vehicle thermal management system in the self-cleaning mode under the control of the controller includes the following steps: Step S1: the controller controls the first pressure sensor and the second pressure sensor to respectively detect the pressure at the outlet of the first filter block and the second filter block in real time, obtain the first filter pressure and the second filter pressure, and further judge whether at least one of the first filter pressure and the second filter pressure is lower than the filter pressure threshold value. If the judgment result is "yes", the cleaning mode operation ends; if the judgment result is "no", the operation continues in the cleaning mode; Step S2: the compressor is turned on to the maximum speed, the ports a and b in the first three-way valve and the second three-way valve are all opened, the port c is closed, the first expansion valve is fully opened, the solenoid valve is opened, and the second expansion valve and the third expansion valve are closed; Step S3: the compressor is kept running at the maximum speed, the solenoid valve is closed, and the third expansion valve is opened; Step S4: the compressor is kept running at the maximum speed, the third expansion valve is closed, and the second expansion valve is opened; Step S5: Repeat steps S1-S4 for several times. Finally, open the c port of the first three-way valve and the second three-way valve and close the b port, and the self-cleaning mode ends.

10. The control method of the thermal management system of a new energy vehicle according to claim 9, characterized in that: in, The supercooling threshold is 5° C., the superheating threshold is 10° C., the filtering pressure threshold is 14 barA, and the number of cycles in step S5 is 3 to 5 times.

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