Circulation control system and air conditioner

Abstract

The utility model provides a circulation control system and an air conditioner, and relates to the technical field of air conditioners. The circulation control system comprises a compressor, a four-way valve, a condenser, a first filter, an electronic expansion valve, a second filter, an evaporator, a gas-liquid separator, a third filter, a refrigerant circulation pipeline and a controller. The compressor, the four-way valve and the gas-liquid separator are sequentially connected end to end through the refrigerant circulating pipeline, and the four-way valve, the condenser, the first filter, the electronic expansion valve, the second filter and the evaporator are sequentially connected end to end through the refrigerant circulating pipeline. The number of filter screens of the third filter is larger than that of filter screens of the first filter and the second filter; the third filter is arranged on the refrigerant circulating pipeline between the four-way valve and the gas-liquid separator; the controller is electrically connected with the compressor, the four-way valve and the electronic expansion valve. According to the utility model, more impurities can be filtered out, and the blockage phenomenon is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of air conditioning, in particular to a circulation control system and an air conditioner. Background Art

[0002] Air conditioners are common household appliances in people's daily lives. They can adjust parameters such as temperature, humidity, cleanliness and air flow rate in the room to meet human comfort requirements. Electronic expansion valves are widely used in air conditioners because of their large cooling capacity adjustment range, high control accuracy and low cost.

[0003] There may be impurities such as metal debris, solder resist residue, grease, etc. in the piping system inside the air conditioner. In the related art, filters are installed before and after the electronic expansion valve to filter out the above impurities.

[0004] Most of the impurities in the piping system will be filtered out by the filter. However, it is difficult for the filter to filter out some tiny impurities, resulting in more impurities in the piping system, which can easily cause blockage and affect system performance and reliability. Utility Model Content

[0005] The embodiment of the utility model provides a circulation control system and an air conditioner, which can filter out more impurities, reduce the occurrence of blockage, improve system performance and enhance reliability.

[0006] In a first aspect, an embodiment of the utility model provides a circulation control system, the circulation control system comprising a compressor, a four-way valve, a condenser, a first filter, an electronic expansion valve, a second filter, an evaporator, a gas-liquid separator, a third filter, a refrigerant circulation pipeline and a controller;

[0007] The compressor, the four-way valve, and the gas-liquid separator are connected end to end in sequence through the refrigerant circulation pipeline, and the four-way valve, the condenser, the first filter, the electronic expansion valve, the second filter, and the evaporator are connected end to end in sequence through the refrigerant circulation pipeline;

[0008] The mesh number of the third filter is greater than the mesh number of the first filter and the second filter; the third filter is arranged on the refrigerant circulation pipeline between the four-way valve and the gas-liquid separator;

[0009] The controller is electrically connected to the compressor, the four-way valve, and the electronic expansion valve respectively.

[0010] In a possible implementation, the circulation control system further includes a first solenoid valve and a second solenoid valve, wherein the first solenoid valve is arranged on a refrigerant circulation pipeline between the four-way valve and the gas-liquid separator, and the first solenoid valve and the third filter are arranged on different refrigerant circulation pipelines respectively; the second solenoid valve is arranged at a refrigerant inlet of the third filter;

[0011] The controller is electrically connected to the first solenoid valve and the second solenoid valve respectively, and is configured to control the first solenoid valve and the second solenoid valve to be opened or closed.

[0012] In a possible implementation manner, the circulation control system further includes a third solenoid valve, and the third solenoid valve is disposed at a refrigerant outlet of the third filter;

[0013] The controller is electrically connected to the third solenoid valve, and is configured to control the third solenoid valve to be opened or closed.

[0014] In a possible implementation manner, the third filter is a Y-type filter.

[0015] In a possible implementation, the Y-type filter is configured with an M-mesh filter screen, and the first filter and the second filter are respectively configured with N-mesh filter screens; wherein, 80≤N≤200, N+80<M<350.

[0016] In a possible implementation, the circulation control system further includes a first pressure sensor and a second pressure sensor; the first pressure sensor is disposed at the exhaust port of the compressor, and the second pressure sensor is disposed at the intake port of the compressor;

[0017] The first pressure sensor is used to detect the exhaust pressure of the compressor; the second pressure sensor is used to detect the suction pressure of the compressor;

[0018] The first pressure sensor and the second pressure sensor are both electrically connected to the controller.

[0019] In a possible embodiment, the circulation control system also includes a first temperature sensor and a second temperature sensor; the first temperature sensor is arranged at the exhaust port of the compressor, and the second temperature sensor is arranged at the intake port of the compressor; the first temperature sensor is used to detect the exhaust temperature of the compressor, and the second temperature sensor is used to detect the intake temperature of the compressor; the first temperature sensor and the second temperature sensor are both electrically connected to the controller.

[0020] In a possible implementation, the circulation control system further includes an oil separator, and the oil separator is disposed on the refrigerant circulation pipeline between the compressor and the four-way valve.

[0021] In a possible implementation manner, the circulation control system further includes a fourth filter, and the fourth filter is disposed on the refrigerant circulation pipeline between the oil separator and the compressor.

[0022] In a second aspect, an embodiment of the present utility model provides an air conditioner, which includes a cabinet, a panel, and a circulation control system as described in any one of the first aspects.

[0023] The circulation control system and air conditioner provided by the embodiment of the utility model include a compressor, a four-way valve, a condenser, a first filter, an electronic expansion valve, a second filter, an evaporator, a gas-liquid separator, a third filter, a refrigerant circulation pipeline and a controller; the compressor, the four-way valve, and the gas-liquid separator are connected end to end through the refrigerant circulation pipeline in sequence, and the four-way valve, the condenser, the first filter, the electronic expansion valve, the second filter, and the evaporator are connected end to end through the refrigerant circulation pipeline in sequence; the mesh number of the third filter is greater than the mesh number of the first filter and the second filter; the third filter is arranged on the refrigerant circulation pipeline between the four-way valve and the gas-liquid separator; the controller is electrically connected to the compressor, the four-way valve, and the electronic expansion valve respectively. In addition to arranging filters before and after the electronic expansion valve, the circulation control system also arranges a third filter between the four-way valve and the gas-liquid separator. Since the mesh number of the third filter is greater than the mesh number of the first filter and the second filter, the third filter can filter out impurities passing through the first filter and the second filter, thereby filtering out more impurities, so that there are fewer impurities in the circulation control system, reducing the occurrence of blockage, improving system performance and improving reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings herein are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present utility model, and together with the description, are used to explain the principles of the present utility model.

[0025] Figure 1 A schematic diagram of a circulation control system provided by an embodiment of the utility model;

[0026] Figure 2 Another schematic diagram of a circulation control system provided by an embodiment of the utility model;

[0027] Figure 3 A schematic diagram of an air conditioner provided by an embodiment of the utility model;

[0028] Figure 4A flow chart of a control method provided by an embodiment of the utility model;

[0029] Figure 5 Another flow chart of a control method provided by an embodiment of the utility model.

[0030] Description of reference numerals:

[0031] 10-compressor; 11-four-way valve; 12-condenser; 13-electronic expansion valve; 131-first electronic expansion valve; 132-second electronic expansion valve; 14-evaporator; 15-gas-liquid separator; 16-external fan; 17-indoor fan; 181-first stop valve; 182-second stop valve; 19-oil separator; 20-first filter; 21-second filter; 201-first valve pre-filter; 202-second valve pre-filter; 211-first valve post-filter; 212-second valve post-filter; 22-fourth filter; 30-third filter; 31-first solenoid valve; 32-second solenoid valve; 33-third solenoid valve; 40-first pressure sensor; 41-second pressure sensor; 50-first temperature sensor; 51-second temperature sensor.

[0032] The above drawings have shown clear embodiments of the present invention, which will be described in more detail below. These drawings and text descriptions are not intended to limit the scope of the present invention in any way, but to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0033] Here, exemplary embodiments will be described in detail, examples of which are shown in the accompanying 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 embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the utility model. Instead, they are only examples of devices and methods consistent with some aspects of the utility model as detailed in the attached claims.

[0034] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0035] In the present invention, unless otherwise clearly specified and limited, the terms "installation", "connection", "fixation" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0037] In the above description, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0038] As the background technology, air conditioners are household appliances commonly used in people's daily lives. They can adjust parameters such as temperature, humidity, cleanliness and air flow rate of the air in the room to meet the requirements of human comfort. Electronic expansion valves are widely used in air conditioners because of their advantages of large refrigeration capacity adjustment range, high control accuracy and low cost. When installing and welding air conditioners, due to complex engineering, many welding pipelines, and difficulty in controlling engineering impurities, debris will inevitably be generated. And there may be impurities such as metal debris, solder resist residues, grease, etc. in the pipeline system inside the air conditioner. Impurities may come from each component of the air conditioning system, such as compressors, evaporators, condensers, connecting pipes, etc. In the related art, filters are installed before and after the electronic expansion valve, and the filters are used to filter the above impurities to avoid impurities clogging the electronic expansion valve and causing electronic expansion valve failure. Most of the impurities in the pipeline system will be filtered out by the filter, but for some fine impurities, it is difficult for the filter to filter them out, resulting in more impurities in the pipeline system, which is easy to cause blockage and affect performance.

[0039] In order to solve the above problems, the utility model provides a circulation control system applied to an air conditioner. In addition to arranging filters before and after the electronic expansion valve, the circulation control system also arranges a third filter between the four-way valve and the gas-liquid separator. Since the mesh number of the third filter is greater than the mesh number of the first filter and the second filter, the third filter can filter out impurities passing through the first filter and the second filter, thereby filtering out more impurities, so that there are fewer impurities in the circulation control system, reducing the occurrence of blockage, improving system performance and increasing reliability.

[0040] The circulation control system and the air conditioner provided by the embodiment of the utility model are described in detail below in conjunction with specific embodiments.

[0041] like Figure 1 As shown, an embodiment of the utility model provides a circulation control system, including a compressor 10, a four-way valve 11, a condenser 12, a first filter 20, an electronic expansion valve 13, a second filter 21, an evaporator 14, a gas-liquid separator 15, a third filter 30, a refrigerant circulation pipeline and a controller; the compressor 10, the four-way valve 11, and the gas-liquid separator 15 are connected end to end through the refrigerant circulation pipeline in sequence, and the four-way valve 11, the condenser 12, the first filter 20, the electronic expansion valve 13, the second filter 21, and the evaporator 14 are connected end to end through the refrigerant circulation pipeline in sequence; the mesh number of the third filter 30 is greater than the mesh number of the first filter 20 and the second filter 21; the third filter 30 is arranged on the refrigerant circulation pipeline between the four-way valve 11 and the gas-liquid separator 15; the controller is electrically connected to the compressor 10, the four-way valve 11, and the electronic expansion valve 13, respectively.

[0042] Among them, the circulation control system can provide both refrigeration and heating functions. Taking the refrigeration function as an example, the compressor 10 is used to pressurize the refrigerant. After the refrigerant is pressurized by the compressor 10, it becomes a high-temperature and high-pressure gas state and enters the condenser 12. After the high-temperature and high-pressure gas state refrigerant enters the condenser 12, it condenses and liquefies to release heat and becomes a low-temperature and high-pressure liquid. The refrigerant in the low-temperature and high-pressure liquid state flows out of the condenser 12 and enters the electronic expansion valve 13. After the electronic expansion valve 13 reduces the pressure, it becomes a low-temperature and low-pressure liquid and flows into the evaporator 14. After the low-temperature and low-pressure liquid refrigerant enters the evaporator 14, it vaporizes and absorbs heat to become a gaseous refrigerant. The gaseous refrigerant enters the gas-liquid separator 15. After the liquid droplets are separated from the gaseous refrigerant by the gas-liquid separator 15, it flows back to the inlet of the compressor 10 through the refrigerant circulation pipeline to carry out the next circulation of the refrigerant.

[0043] The four-way valve 11 is switched from the cooling pipeline to the heating pipeline, so that the refrigerant circulates in the opposite direction to the cooling process.

[0044] Among them, the refrigerant is also called refrigerant, which is a substance that transfers heat through evaporation and condensation in the air-conditioning system, such as Freon.

[0045] like Figure 2 As shown, the circulation control system further includes an outdoor fan 16 and an indoor fan 17. The wind blown by the outdoor fan 16 passes through the condenser 12 and absorbs the heat energy of the condenser 12. The wind blown by the indoor fan 17 passes through the evaporator 14 and blows the cold wind into the room.

[0046] like Figure 2 As shown, a first electronic expansion valve 131 and a second electronic expansion valve 132 are provided on the refrigerant circulation pipeline between the condenser 12 and the evaporator 14, and filters are provided before and after the first electronic expansion valve 131 and the second electronic expansion valve 132. Accordingly, the first filter 20 includes a first pre-valve filter 201 provided before the first electronic expansion valve 131 and a second pre-valve filter 202 provided before the second electronic expansion valve 132, and the second filter 21 includes a first post-valve filter 211 provided after the first electronic expansion valve 131 and a second post-valve filter 212 provided after the second electronic expansion valve 132.

[0047] Figure 2 The dotted line frame is the indoor unit, which includes a second electronic expansion valve 132, an evaporator 14, an indoor fan 17, and a second pre-valve filter 202 and a second post-valve filter 212 respectively arranged before and after the second electronic expansion valve 132.

[0048] like Figure 2As shown, a first stop valve 181 is further provided between the first electronic expansion valve 131 and the second electronic expansion valve 132 , and a second stop valve 182 is further provided between the evaporator 14 and the four-way valve 11 .

[0049] It should be noted that the solid black arrows on the refrigerant circulation pipes represent the flow direction of the refrigerant during cooling, and the hollow arrows represent the flow direction of the refrigerant during heating.

[0050] It should be noted that the present invention does not impose any restrictions on the specific structure and model of the controller, as long as the controller can achieve the above functions, and the controller can be the original controller of the air conditioner or a separate controller set to execute the control method of the controller of the present invention. The technicians can set the structure and model of the controller according to actual usage requirements.

[0051] The utility model provides a circulation control system used in an air conditioner. In addition to arranging a first filter 20 and a second filter 21 before and after an electronic expansion valve 13, the circulation control system also arranges a third filter 30 between a four-way valve 11 and a gas-liquid separator 15. Since the mesh number of the third filter 30 is greater than the mesh number of the first filter 20 and the second filter 21, the third filter 30 can filter out impurities passing through the first filter 20 and the second filter 21, so that there are fewer impurities in the circulation control system, the occurrence of blockage is reduced, the system performance is improved, and the reliability is increased. On this basis, the impurities in the circulation control system may come from each component constituting the circulation control system. In order to filter the impurities at the filter of the third filter 30, the third filter 30 is installed between the four-way valve 11 and the gas-liquid separator 15. During the circulation process, the refrigerant will eventually pass through the third filter 30 to achieve the purpose of filtering impurities, while preventing the liquid refrigerant from flowing back into the compressor 10 and causing damage to the compressor 10.

[0052] In a possible implementation, Figure 2 As shown, the circulation control system also includes a first solenoid valve 31 and a second solenoid valve 32. The first solenoid valve 31 is arranged on the refrigerant circulation pipeline between the four-way valve 11 and the gas-liquid separator 15, and the first solenoid valve 31 and the third filter 30 are respectively arranged on different refrigerant circulation pipelines; the second solenoid valve 32 is arranged at the refrigerant inlet of the third filter 30; the controller is electrically connected to the first solenoid valve 31 and the second solenoid valve 32, respectively, and the controller is configured to control the first solenoid valve 31 and the second solenoid valve 32 to open or close.

[0053] There are two passages from the four-way valve 11 to the gas-liquid separator 15, the first is the four-way valve 11-first solenoid valve 31-gas-liquid separator 15, and the second is the four-way valve 11-second solenoid valve 32-third filter 30-gas-liquid separator 15. Based on this, the first solenoid valve 31 is closed and the second solenoid valve 32 is opened, so that the first passage is closed and the second passage is opened, and impurities are filtered through the third filter 30 in the second passage. After the impurities are filtered to the third filter 30, the first solenoid valve 31 is opened and the second solenoid valve 32 is closed, so that the first passage is opened and the second passage is closed, and the impurities are isolated in the third filter 30, so that the impurities in the third filter 30 cannot return to the refrigerant circulation pipeline, thereby reducing impurities in the system operation and ensuring the cleanliness of the system.

[0054] In a possible implementation, Figure 2 As shown, the circulation control system also includes a third solenoid valve 33, which is arranged at the refrigerant outlet of the third filter 30; the controller is electrically connected to the third solenoid valve 33, and the controller is configured to control the third solenoid valve 33 to be opened or closed.

[0055] The opening and closing timings of the third solenoid valve 33 are the same as those of the second solenoid valve 32. Specifically, the third solenoid valve 33 is opened when the second solenoid valve 32 is opened, and is closed when the second solenoid valve 32 is closed. By respectively arranging the second solenoid valve 32 and the third solenoid valve 33 before and after the third filter 30, a double guarantee of isolating impurities in the third filter 30 is achieved.

[0056] In a possible implementation manner, the third filter 30 is a Y-type filter.

[0057] Among them, the Y-type filter has the characteristics of advanced structure, small resistance and convenient sewage discharge.

[0058] In a possible implementation, the Y-type filter is configured with an M-mesh filter screen, and the first filter and the second filter are respectively configured with N-mesh filter screens; wherein, 80≤N≤200, N+80<M<350.

[0059] The value of N is determined according to the experimental test selection and the system pressure loss. For example, N can be 100. In order to achieve a greater filtering effect, ensure the cleanliness of the system, and avoid excessive pressure loss, N+80<M<350.

[0060] In a possible implementation, Figure 2As shown, the circulation control system also includes a first pressure sensor 40 and a second pressure sensor 41; the first pressure sensor 40 is arranged at the exhaust port of the compressor 10, and the second pressure sensor 41 is arranged at the intake port of the compressor 10; the first pressure sensor 40 is used to detect the exhaust pressure of the compressor 10; the second pressure sensor 41 is used to detect the intake pressure of the compressor 10; the first pressure sensor 40 and the second pressure sensor 41 are both electrically connected to the controller.

[0061] The first pressure sensor 40 detects the exhaust pressure of the compressor 10 , and the controller can obtain the detection data of the first pressure sensor 40 . The second pressure sensor 41 detects the intake pressure of the compressor 10 , and the controller can obtain the detection data of the second pressure sensor 41 .

[0062] In a possible implementation, Figure 2 As shown, the circulation control system also includes a first temperature sensor 50 and a second temperature sensor 51; the first temperature sensor 50 is arranged at the exhaust port of the compressor 10, and the second temperature sensor 51 is arranged at the intake port of the compressor 10; the first temperature sensor 50 is used to detect the exhaust temperature of the compressor 10, and the second temperature sensor 51 is used to detect the intake temperature of the compressor 10; the first temperature sensor 50 and the second temperature sensor 51 are both electrically connected to the controller.

[0063] The first temperature sensor 50 detects the exhaust temperature of the compressor 10 , and the controller can obtain the detection data of the first temperature sensor 50 . The second temperature sensor 51 detects the intake temperature of the compressor 10 , and the controller can obtain the detection data of the second temperature sensor 51 .

[0064] In a possible implementation, Figure 2 As shown, the circulation control system further includes an oil separator 19, which is disposed on the refrigerant circulation pipeline between the compressor 10 and the four-way valve 11. The oil separator 19 is used to separate the lubricating oil from the gaseous refrigerant and return it to the compressor 10 to prevent the compressor 10 from burning due to lack of oil.

[0065] In a possible implementation, Figure 2 As shown, the circulation control system further includes a fourth filter 22, which is disposed on the refrigerant circulation pipeline between the oil separator 19 and the compressor 10, and is used to filter impurities in the lubricating oil.

[0066] The utility model also provides an air conditioner, such as Figure 3As shown, the air conditioner comprises a housing 1, a panel 2 and a circulation control system 3 as in the above embodiment. The circulation control system 3 is arranged inside the housing 1, the panel 2 is electrically connected to the controller in the circulation control system 3, and the panel 2 is arranged on the housing 1 for the user to view or operate.

[0067] The utility model also provides a control method, which is described in detail below in conjunction with the accompanying drawings.

[0068] like Figure 4 As shown, the control method is applied to a circulation control system, which includes a compressor 10, a four-way valve 11, a condenser 12, a first filter 20, an electronic expansion valve 13, a second filter 21, an evaporator 14, a gas-liquid separator 15, a third filter 30, a refrigerant circulation pipeline and a controller;

[0069] The compressor 10, the four-way valve 11, and the gas-liquid separator 15 are connected end to end in sequence through a refrigerant circulation pipeline, and the four-way valve 11, the condenser 12, the first filter 20, the electronic expansion valve 13, the second filter 21, and the evaporator 14 are connected end to end in sequence through a refrigerant circulation pipeline;

[0070] The mesh number of the third filter 30 is greater than that of the first filter 20 and the second filter 21; the third filter 30 is disposed on the refrigerant circulation pipeline between the four-way valve 11 and the gas-liquid separator 15;

[0071] The controller is electrically connected to the compressor 10 , the four-way valve 11 , and the electronic expansion valve 13 , respectively.

[0072] Control methods include:

[0073] S100 , after power-on, when the electronic expansion valve 13 is not reset, the pulse step number of the electronic expansion valve 13 is increased to a preset pulse step number.

[0074] After the air conditioner is powered on, step S100 is performed. The power-on may be the first power-on or every power-on.

[0075] The preset pulse step number B can be calculated according to the preset formula, which is B = B com +B max , where B com is the number of pulse steps corresponding to the factory setting opening of the electronic expansion valve 13, B max is the maximum pulse step number corresponding to the maximum opening of the electronic expansion valve 13. By opening the electronic expansion valve 13 according to the preset pulse step number, the system startup pressure difference is reduced.

[0076] It should be noted that if the number of electronic expansion valves 13 in the circulation control system is greater than 1, it is determined whether each electronic expansion valve 13 is reset, and if there is an electronic expansion valve 13 that has not been reset, the pulse step number is increased to the preset pulse step number for each electronic expansion valve 13.

[0077] S200 , controlling the compressor 10 to start, and controlling the compressor 10 to first increase the frequency and then reduce the frequency, so as to filter impurities in the refrigeration pipeline through the third filter 30 .

[0078] After the pulse number of the electronic expansion valve 13 is increased, the compressor 10 starts to operate and increases the frequency, thereby accelerating the flow rate of the refrigerant, so that impurities quickly enter the third filter 30 .

[0079] In the related art, for some fine impurities, it is difficult for the filters arranged before and after the electronic expansion valve 13 to filter them out, causing these impurities to enter the electronic expansion valve 13. Since the diameter of the electronic expansion valve 13 is relatively small, the impurities are easily blocked at the valve port, which in turn causes the valve port to become stuck or unable to be completely closed, thereby causing a loss of cooling capacity during refrigeration operation, and thus causing poor performance of the air conditioner. The compressor 10 in this embodiment first increases the frequency and then decreases the frequency, thereby increasing the inlet pressure of the electronic expansion valve 13, thereby providing sufficient pressure to flush away the impurities accumulated at the valve port, and by increasing and decreasing the frequency, the refrigerant flow rate changes, further flushing the valve port of the electronic expansion valve 13.

[0080] S300 , when the compressor 10 is reduced in frequency to the switching frequency, the four-way valve 11 is controlled to switch, and the compressor 10 is controlled to first increase in frequency and then stop running, so as to filter impurities in the heating pipeline through the third filter 30 .

[0081] After filtering impurities in the refrigeration pipeline, impurities can also be filtered in the heating pipeline by reversing the four-way valve 11 from the refrigeration pipeline to the heating pipeline. Similarly, the compressor 10 increases the frequency to increase the refrigerant flow rate, and further flushes the valve port of the electronic expansion valve 13, so that impurities quickly enter the third filter 30, thereby ensuring the cleanliness of the electronic expansion valve 13.

[0082] S400, controlling the electronic expansion valve 13 to reset.

[0083] Through this control method, the refrigerant repeatedly flushes impurities such as metal, solder resist residue, grease, etc. in the refrigerant circulation pipeline, allowing the impurities to be quickly filtered out at the filter screen of the third filter 30, and flushing away fine debris in the electronic expansion valve 13 under a certain pressure difference, thereby ensuring the cleanliness of the circulation control system and the electronic expansion valve 13.

[0084] After the compressor 10 stops running, the electronic expansion valve 13 performs a reset and zeroing action, and the number of reset pulse steps is B res =Bmax +ΔB res +B com , and marked as reset. Among them, ΔB res The value of is set according to the selection and experimental test of the electronic expansion valve 13, and ΔB res The value range is [50,200] pls. For example, the ΔB of the electronic expansion valve 13 in the circulation control system in this embodiment is res =100pls.

[0085] When the unit has been marked reset, the unit can be controlled and operated normally.

[0086] Figure 5 is Figure 4 On this basis, further refine the operation steps.

[0087] like Figure 5 As shown, after power-on, it is determined whether the electronic expansion valve 13 is reset. Determining whether the electronic expansion valve 13 is reset can be specifically: obtaining the pulse step number of the electronic expansion valve 13. If the pulse step number is the pulse step number corresponding to the reset, it means that the electronic expansion valve 13 is reset; otherwise, it means that the electronic expansion valve 13 is not reset. In addition, a reset mark will be generated after the electronic expansion valve 13 is reset, so the reset mark can also be obtained. If the reset mark is obtained, it means that the electronic expansion valve 13 is reset, otherwise, it means that the electronic expansion valve 13 is not reset.

[0088] In a possible embodiment, the circulation control system also includes a first solenoid valve 31, a second solenoid valve 32 and a third solenoid valve 33. The first solenoid valve 31 is arranged on the refrigerant circulation pipeline between the four-way valve 11 and the gas-liquid separator 15, and the first solenoid valve 31 and the third filter 30 are respectively arranged on different refrigerant circulation pipelines; the second solenoid valve 32 is arranged at the refrigerant inlet of the third filter 30, and the third solenoid valve 33 is arranged at the refrigerant outlet of the third filter 30; the controller is electrically connected to the first solenoid valve 31, the second solenoid valve 32 and the third solenoid valve 33, respectively.

[0089] like Figure 5 As shown, when the electronic expansion valve 13 is reset, the first solenoid valve 31 is normally opened, the second solenoid valve 32 and the third solenoid valve 33 are normally closed, and the unit is controlled and operated normally.

[0090] like Figure 5 As shown, when the electronic expansion valve 13 is not reset, the first solenoid valve 31 is closed, the second solenoid valve 32 is opened, and the third solenoid valve 33 is opened, so that impurities are filtered through the third filter 30 .

[0091] When the electronic expansion valve 13 is reset, the first solenoid valve 31 is normally opened, the second solenoid valve 32 is normally closed, and the third solenoid valve 33 is normally closed. Then, the pulse step number of the electronic expansion valve 13 is increased to B=B com +B max .

[0092] according to Figure 4 It can be seen from the illustrated embodiment that after the pulse step number of the electronic expansion valve 13 is increased, step S200 is executed, that is, the compressor 10 is controlled to start, and the compressor 10 is controlled to first increase the frequency and then decrease the frequency, so as to filter impurities in the refrigeration pipeline through the third filter 30. In a possible implementation, the step S200 of controlling the compressor 10 to first increase the frequency and then decrease the frequency includes: controlling the compressor 10 to increase the frequency and increase the frequency to a first operating frequency; after the compressor 10 operates at the first operating frequency for a first period of time, controlling the compressor 10 to decrease the frequency.

[0093] like Figure 5 As shown, the compressor 10 starts at a frequency F res0 Start, and gradually increase the frequency to the first operating frequency F res1 , the running time is T res1 , and then the compressor 10 gradually reduces the frequency to the switching frequency F ex Among them, F res1 >F res0 , and the first operating frequency can be set as needed. The first duration T res1 The value range is [5,8], and the unit is min (minute). ex The value range is [15,50], and the unit is Hz (Hertz), for example, F ex =30Hz.

[0094] according to Figure 4 As can be seen from the embodiment shown, when the compressor frequency is reduced to the switching frequency F ex When the four-way valve 11 is controlled to switch direction. In a possible implementation manner, the control method provided by the utility model further includes:

[0095] During the operation of the compressor 10, the suction pressure and the exhaust pressure of the compressor 10 are obtained;

[0096] Accordingly, when the compressor 10 is reduced in frequency to the reversing frequency in step S300, the four-way valve 11 is controlled to be reversing, including:

[0097] When the compressor 10 is reduced in frequency to the switching frequency, the difference between the exhaust pressure and the suction pressure is determined as the current pressure difference of the four-way valve 11;

[0098] When the pressure difference meets the reversing condition, the four-way valve 11 is controlled to reverse;

[0099] When the pressure difference does not meet the reversing condition, the compressor 10 is controlled to continue running for a second period of time, and then the four-way valve 11 is controlled to reverse.

[0100] During the operation of the compressor 10, the exhaust pressure P detected by the first pressure sensor 40 is obtained in real time. d and the suction pressure P detected by the second pressure sensor 41 S , then P d -P S is the pressure difference of the four-way valve 11. The switching condition is P d -P S >ΔP1 or P d -P S >ΔP2. The value of ΔP1 is determined according to the selection of the four-way valve 11 and the switching pressure difference. The value range of ΔP1 is [4,15]. For example, ΔP1=5Bar, and P S ≤P S0 , P S0 The value range is [4,20]. For example, P S0 =10Bar; the value of ΔP2 is determined according to the selection of the four-way valve 11 and the switching pressure difference, and the value range of ΔP2 is [10,20], for example, ΔP2=12Bar.

[0101] like Figure 5 As shown, when the pressure difference meets the switching condition P d -P S >ΔP1 or P d -P S >ΔP2, the four-way valve 11 switches direction. d -P S >ΔP1 and P d -P S >ΔP2, the compressor 10 continues to operate for a second time period T ex After that, the four-way valve 11 is forced to switch. The second time length T ex The value range is [2,5]. For example, T ex =2min.

[0102] according to Figure 4 It can be seen from the illustrated embodiment that after the four-way valve 11 is switched, the compressor 10 first increases the frequency and then stops running. In a possible implementation, controlling the compressor 10 to first increase the frequency and then stop running in step S300 includes:

[0103] Controlling the compressor 10 to increase the frequency and increase the frequency to a second operating frequency;

[0104] After the compressor 10 operates at the second operating frequency for a third period of time, the compressor 10 is controlled to stop operating.

[0105] Among them, the second operating frequency F res2 >F res0 , and the second operating frequency can be set as needed. The third duration T res2 The value range is [3,5], and the unit is min.

[0106] like Figure 5 As shown, the compressor 10 gradually increases the frequency to the second operating frequency F res2 , the running time is T res2 Then stop running and reset the electronic expansion valve.

[0107] Through the above logic control, the refrigerant circulation pipeline, electronic expansion valve 13, compressor 10 and other components in the circulation control system are cleaned, and impurities will be gathered in the third filter 30. By closing the second solenoid valve 32, closing the third solenoid valve 33, and then opening the third filter 30, the impurities inside are cleaned. After the electronic expansion valve 13 is reset and zeroed, when the unit is operating normally, the first solenoid valve 31 is normally open, and the second solenoid valve 32 and the third solenoid valve 33 are kept normally closed.

[0108] Under this control method, after power-on, the electronic expansion valve 13 is opened to reduce resistance, and impurities are quickly isolated in the third filter 30 under the changing flow rate of the refrigerant and repeated flushing; when the unit performs the "cleaning" action, the impurities are flushed away by a sufficient pressure difference to prevent impurities generated by installation, welding, etc. from accumulating at the valve port, thereby damaging the valve port when closing the valve, thereby ensuring the cleanliness of the electronic expansion valve 13; after the "cleaning" process is completed, the third filter 30 and the filter screen are cleaned by closing the second solenoid valve 32 and the third solenoid valve 33, which can reduce impurities in the system and further improve the reliability of the electronic expansion valve 13 and the system operation.

[0109] Finally, it should be noted that those skilled in the art will easily think of other embodiments of the utility model after considering the specification and practicing the utility model disclosed herein. The utility model is intended to cover any variation, use or adaptation of the utility model, which follows the general principles of the utility model and includes common knowledge or conventional technical means in the technical field not disclosed by the utility model, is not limited to the precise structure described above and shown in the drawings, and can be modified and changed in various ways without departing from the scope thereof. The scope of the utility model is limited only by the appended claims.

Claims

1. A circulation control system, characterized in that: The circulation control system includes a compressor, a four-way valve, a condenser, a first filter, an electronic expansion valve, a second filter, an evaporator, a gas-liquid separator, a third filter, a refrigerant circulation pipeline and a controller; The compressor, the four-way valve, and the gas-liquid separator are connected end to end in sequence through the refrigerant circulation pipeline, and the four-way valve, the condenser, the first filter, the electronic expansion valve, the second filter, and the evaporator are connected end to end in sequence through the refrigerant circulation pipeline; The mesh number of the third filter is greater than the mesh number of the first filter and the second filter; the third filter is arranged on the refrigerant circulation pipeline between the four-way valve and the gas-liquid separator; The controller is electrically connected to the compressor, the four-way valve, and the electronic expansion valve respectively.

2. The circulation control system according to claim 1, characterized in that: The circulation control system further includes a first solenoid valve and a second solenoid valve, wherein the first solenoid valve is arranged on a refrigerant circulation pipeline between the four-way valve and the gas-liquid separator, and the first solenoid valve and the third filter are arranged on different refrigerant circulation pipelines respectively; the second solenoid valve is arranged at a refrigerant inlet of the third filter; The controller is electrically connected to the first solenoid valve and the second solenoid valve respectively, and is configured to control the first solenoid valve and the second solenoid valve to be opened or closed.

3. The circulation control system according to claim 2, characterized in that: The circulation control system further comprises a third solenoid valve, which is arranged at the refrigerant outlet of the third filter; The controller is electrically connected to the third solenoid valve, and is configured to control the third solenoid valve to be opened or closed.

4. The circulation control system according to claim 1, characterized in that: The third filter is a Y-type filter.

5. The circulation control system according to claim 4, characterized in that: The Y-type filter is equipped with an M-mesh filter screen, and the first filter and the second filter are respectively equipped with N-mesh filter screens; wherein, 80≤N≤200, N+80<M<350.

6. The circulation control system according to claim 1, characterized in that: The circulation control system further includes a first pressure sensor and a second pressure sensor; the first pressure sensor is arranged at the exhaust port of the compressor, and the second pressure sensor is arranged at the suction port of the compressor; The first pressure sensor is used to detect the exhaust gas pressure of the compressor; The second pressure sensor is used to detect the suction pressure of the compressor; The first pressure sensor and the second pressure sensor are both electrically connected to the controller.

7. The circulation control system according to claim 1, characterized in that: The circulation control system also includes a first temperature sensor and a second temperature sensor; the first temperature sensor is arranged at the exhaust port of the compressor, and the second temperature sensor is arranged at the intake port of the compressor; the first temperature sensor is used to detect the exhaust temperature of the compressor, and the second temperature sensor is used to detect the intake temperature of the compressor; the first temperature sensor and the second temperature sensor are both electrically connected to the controller.

8. The circulation control system according to claim 1, characterized in that: The circulation control system further includes an oil separator, which is arranged on the refrigerant circulation pipeline between the compressor and the four-way valve.

9. The circulation control system according to claim 8, characterized in that: The circulation control system further includes a fourth filter, which is disposed on a refrigerant circulation pipeline between the oil separator and the compressor.

10. An air conditioner, characterized in that: The air conditioner comprises a cabinet, a panel and a circulation control system as claimed in any one of claims 1 to 9.

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