Control method of electronic expansion valve, heat pump system and storage medium

Abstract

The invention discloses a control method of an electronic expansion valve, a heat pump system and a storage medium. The method comprises the steps that when a shutdown instruction of the heat pump system is received, a pressure value related to operation of an electronic expansion valve in the heat pump system is detected; and the opening degree of the electronic expansion valve is controlled according to the pressure value, so that the heat pump system reaches a pressure balance state. The invention aims to reduce the abrasion of the electronic expansion valve after the heat pump system is shut down and prolong the service life of the electronic expansion valve.

Description

Technical Field

[0001] The present invention relates to the technical field of heat pumps, and in particular to a control method for an electronic expansion valve, a heat pump system and a storage medium. Background Art

[0002] Heat pump systems (such as heat pump systems) generally use electronic expansion valves to throttle and reduce pressure to achieve a normal heat exchange cycle.

[0003] At present, when the heat pump system is shut down, the electronic expansion valve is directly controlled to increase its opening to unload and achieve pressure balance. However, a sudden pressure change will occur when the system is shut down. The current control method of the electronic expansion valve is likely to cause wear of the valve needle and other structures in the electronic expansion valve, thereby reducing the service life of the electronic expansion valve. Summary of the invention

[0004] The main purpose of the present invention is to provide a control method for an electronic expansion valve, a heat pump system and a storage medium, aiming to reduce the wear of the electronic expansion valve after the heat pump system is shut down and to increase the service life of the electronic expansion valve.

[0005] To achieve the above object, the present invention provides a control method for an electronic expansion valve, the control method for an electronic expansion valve comprising the following steps:

[0006] When a shutdown command of the heat pump system is received, detecting a pressure value related to the operation of the electronic expansion valve in the heat pump system;

[0007] The opening of the electronic expansion valve is controlled according to the pressure value so that the heat pump system reaches a pressure balance state.

[0008] Optionally, the step of controlling the opening of the electronic expansion valve according to the pressure value so that the heat pump system reaches a pressure balance state includes:

[0009] When the pressure value is not greater than a preset pressure threshold, controlling the electronic expansion valve to increase its opening;

[0010] When the pressure value is greater than the preset pressure threshold, the electronic expansion valve is controlled to maintain a current opening.

[0011] Optionally, the step of controlling the electronic expansion valve to increase its opening degree comprises:

[0012] Controlling the electronic expansion valve to increase to a first preset opening, wherein the preset opening is greater than the current opening of the electronic expansion valve; or,

[0013] The electronic expansion valve is controlled to increase its opening according to the pressure value.

[0014] Optionally, the step of controlling the electronic expansion valve to increase its opening according to the pressure value includes:

[0015] determining a pressure difference between the preset pressure threshold and the pressure value;

[0016] Determining an opening adjustment value according to the pressure difference;

[0017] The electronic expansion valve is controlled to increase its opening degree by the opening degree adjustment value.

[0018] Optionally, when a shutdown instruction of the heat pump system is received, the step of detecting a pressure value related to the operation of the electronic expansion valve in the heat pump system includes:

[0019] When a shutdown command of the heat pump system is received, the pressure values ​​at both ends of the electronic expansion valve are detected respectively to obtain a first pressure value and a second pressure value.

[0020] Optionally, the step of controlling the opening of the electronic expansion valve according to the pressure value so that the heat pump system reaches a pressure balance state includes:

[0021] determining a maximum pressure value between the first pressure value and the second pressure value;

[0022] The opening degree of the electronic expansion valve is controlled according to the maximum pressure value so that the heat pump system reaches a pressure balance state.

[0023] Optionally, when a shutdown instruction of the heat pump system is received, the step of detecting a pressure value related to the operation of the electronic expansion valve in the heat pump system includes:

[0024] When receiving a shutdown instruction of the heat pump system, obtaining the shutdown duration of the heat pump system;

[0025] When the shutdown time reaches a first preset time, a pressure value related to the operation of the electronic expansion valve in the heat pump system is detected.

[0026] Optionally, after the step of controlling the opening of the electronic expansion valve according to the pressure value so that the heat pump system reaches a pressure balance state, the method further includes:

[0027] Obtaining the downtime duration of the heat pump system;

[0028] When the shutdown time reaches a second preset time, the electronic expansion valve is controlled to reset to a second preset opening.

[0029] In addition, in order to achieve the above-mentioned purpose, the present application also proposes a heat pump system, the heat pump system comprising:

[0030] Electronic expansion valve;

[0031] A pressure detection module, wherein the pressure detection module is disposed at at least one end of the electronic expansion valve;

[0032] A control device, wherein the electronic expansion valve and the pressure detection module are both connected to the control device, and the control device comprises: a memory, a processor, and a control program for the electronic expansion valve stored in the memory and executable on the processor, wherein the control program for the electronic expansion valve implements the steps of the control method for the electronic expansion valve as described in any one of the above items when executed by the processor.

[0033] Optionally, the pressure detection module includes a first pressure sensor and a second pressure sensor respectively arranged at two ends of the electronic expansion valve, and the first pressure sensor and the second pressure sensor are both connected to the control device.

[0034] In addition, in order to achieve the above-mentioned purpose, the present application also proposes a storage medium, on which a control program of an electronic expansion valve is stored. When the control program of the electronic expansion valve is executed by a processor, the steps of the control method of the electronic expansion valve as described in any of the above items are implemented.

[0035] The present invention proposes a control method for an electronic expansion valve. When receiving a shutdown command of a heat pump system, the method detects a pressure value related to the operation of the electronic expansion valve in the heat pump system, and adjusts the opening of the electronic expansion valve according to the pressure value to make the system pressure reach a balanced state, thereby ensuring that the opening adjustment of the electronic expansion valve can match the actual pressure state of the system, so as to effectively reduce the wear of the electronic expansion valve after the heat pump system is shut down and increase the service life of the electronic expansion valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A schematic diagram of the structure of a refrigerant system of an embodiment of a heat pump system of the present invention;

[0037] Figure 2 A schematic diagram of the hardware structure involved in the operation of an embodiment of a heat pump system of the present invention;

[0038] Figure 3 It is a flow chart of an embodiment of a control method of an electronic expansion valve of the present invention;

[0039] Figure 4 A schematic flow chart of another embodiment of a method for controlling an electronic expansion valve of the present invention;

[0040] Figure 5 The figure is a flow chart of another embodiment of the control method of the electronic expansion valve of the present invention.

[0041] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0042] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0043] The embodiment of the present invention provides a heat pump system. In this embodiment, the heat pump system is an air conditioner. In other embodiments, the heat pump system may also be other types of equipment, such as a heat pump water heater, a refrigerator, etc.

[0044] In the embodiment of the present invention, refer to Figure 1 and Figure 2 The heat pump system includes a control device 100 , a compressor 200 , a first heat exchanger 400 , an electronic expansion valve 300 , and a second heat exchanger 500 .

[0045] The first heat exchanger 400 , the electronic expansion valve 300 , and the second heat exchanger 500 are connected in sequence, and the first heat exchanger 400 and the second heat exchanger 500 are communicated with the exhaust port of the compressor 200 and the return port of the compressor 200 , respectively.

[0046] In one implementation, the first heat exchanger 400 is connected to the exhaust port, and the second heat exchanger 500 is connected to the return port. When the compressor 200 is turned on, the refrigerant flows through the first heat exchanger 400, the electronic expansion valve 300, and the second heat exchanger 500 in sequence and then flows back to the compressor 200.

[0047] In another implementation, the first heat exchanger 400 is connected to the return port, and the second heat exchanger 500 is connected to the exhaust port. When the compressor 200 is turned on, the refrigerant flows through the second heat exchanger 500, the electronic expansion valve 300, and the first heat exchanger 400 in sequence and then flows back to the compressor 200.

[0048] In another implementation, the heat pump system may further include a reversing assembly 600 (such as a four-way valve, etc.), and the first heat exchanger 400, the second heat exchanger 500, the exhaust port of the compressor 200, and the return port of the compressor 200 are all connected to the reversing assembly 600. The reversing assembly 600 has a first operating state and a second operating state. When the reversing assembly 600 operates in the first operating state, the first heat exchanger 400 is connected to the exhaust port, and the second heat exchanger 500 is connected to the return port. When the compressor 200 is turned on, the refrigerant flows through the first heat exchanger 400, the electronic expansion valve 300, and the second heat exchanger 500 in sequence and then flows back to the compressor 200; when the reversing assembly 600 operates in the second operating state, the first heat exchanger 400 is connected to the return port, and the second heat exchanger 500 is connected to the exhaust port. When the compressor 200 is turned on, the refrigerant flows through the second heat exchanger 500, the electronic expansion valve 300, and the first heat exchanger 400 in sequence and then flows back to the compressor 200.

[0049] Further, in this embodiment, referring to Figure 1 and Figure 2The heat pump system may further include a pressure detection module 700, which is connected to the control device 100 to detect the pressure value related to the operation of the electronic expansion valve 300 in the heat pump system. The pressure detection module 700 may include one or more pressure sensors. In this embodiment, the pressure detection module 700 is disposed at at least one end of the electronic expansion valve 300.

[0050] The pressure detection module 700 includes a first pressure sensor 701 and a second pressure sensor 702 respectively disposed at both ends of the electronic expansion valve 300, and the first pressure sensor 701 and the second pressure sensor 702 are both connected to the control device 100. The first pressure sensor 701 is used to detect the refrigerant pressure at one end of the electronic expansion valve 300, and the second pressure sensor 702 is used to detect the refrigerant pressure at the other end of the electronic expansion valve 300.

[0051] In other embodiments, the pressure detection module 700 may also be disposed on at least one side of the compressor 200 or on the first heat exchanger 400 and / or the second heat exchanger 500 .

[0052] In the embodiment of the present invention, refer to Figure 2 The control device 100 includes: a processor 1001, such as a CPU, a memory 1002, and a timer 1003. Among them, these components are connected and communicated through a communication bus. The memory 1002 can be a high-speed RAM memory or a stable memory (non-volatile memory), such as a disk memory. The memory 1002 can also be a storage device independent of the aforementioned processor 1001.

[0053] Those skilled in the art will understand that Figure 2 The device structure shown in the figure does not constitute a limitation of the device, and may include more or less components than shown in the figure, or combine certain components, or arrange the components differently.

[0054] like Figure 2 As shown, the memory 1002 as a computer storage medium may include a control program for the electronic expansion valve 300 .

[0055] exist Figure 2 In the device shown, the processor 1001 can be used to call the control program of the electronic expansion valve 300 stored in the memory 1002, and execute the relevant step operations of the control method of the electronic expansion valve 300 in the following embodiment.

[0056] An embodiment of the present invention further provides a control method for an electronic expansion valve, which is applied to the above-mentioned heat pump system.

[0057] Reference Figure 3, an embodiment of a control method of an electronic expansion valve of the present application is proposed. In this embodiment, the control method of the electronic expansion valve includes:

[0058] Step S10, when a shutdown instruction of the heat pump system is received, detecting a pressure value related to the operation of the electronic expansion valve in the heat pump system;

[0059] The shutdown command can be input by the user, or generated when the heat pump system reaches the shutdown condition. When the shutdown command of the heat pump system is received, the compressor is controlled to shut down and the pressure value is detected.

[0060] The pressure value can be obtained by obtaining the pressure data currently detected by the above-mentioned pressure detection module, or by obtaining the pressure data detected by the pressure detection module within a period of time after shutdown, or by obtaining the first pressure data detected by the pressure detection module before shutdown and the second pressure data detected after shutdown.

[0061] Step S20, controlling the opening of the electronic expansion valve according to the pressure value so that the heat pump system reaches a pressure balance state.

[0062] The opening control parameters of the electronic expansion valve are determined according to the pressure value. Different pressure values ​​correspond to different opening control parameters of the electronic expansion valve. The operation of the electronic expansion valve is controlled according to the opening control parameters.

[0063] The determined opening control parameter is a parameter that can unload the heat pump system but the impact force on the internal structure of the electronic expansion valve is less than the preset pressure. The opening control parameter includes but is not limited to at least one of the following parameters: target opening, opening adjustment rate, opening adjustment amplitude, opening adjustment ratio, opening adjustment direction (increase opening or decrease opening or maintain current opening), etc.

[0064] In one implementation, an opening control parameter may be determined according to the pressure interval in which the pressure value is located, and the operation of the electronic expansion valve may be controlled according to the opening control parameter.

[0065] In another implementation, the opening control parameter may be determined according to the size relationship or quantity relationship value between the pressure value and the preset pressure value, and the operation of the electronic expansion valve may be controlled according to the opening control parameter.

[0066] An embodiment of the present invention proposes a control method for an electronic expansion valve. When receiving a shutdown command of a heat pump system, the method detects a pressure value related to the operation of the electronic expansion valve in the heat pump system, and adjusts the opening of the electronic expansion valve according to the pressure value to make the system pressure reach a balanced state, thereby ensuring that the opening adjustment of the electronic expansion valve can match the actual pressure state of the system, so as to effectively reduce the wear of the electronic expansion valve after the heat pump system is shut down and increase the service life of the electronic expansion valve.

[0067] Further, based on the above embodiment, another embodiment of the control method of the electronic expansion valve of the present application is proposed. In this embodiment, referring to Figure 4 , the step S20 comprises:

[0068] Step S21, when the pressure value is not greater than a preset pressure threshold, controlling the electronic expansion valve to increase its opening;

[0069] The preset pressure threshold is the maximum pressure allowed to protect the internal structure of the electronic expansion valve from wear when the opening of the electronic expansion valve increases during the shutdown process of the heat pump system.

[0070] When the electronic expansion valve increases its opening, the opening adjustment value can be a preset fixed opening adjustment value to increase the opening, or a target opening adjustment value determined according to the actual operation of the heat pump system, or it can be directly increased to a preset fixed opening.

[0071] In one implementation of this embodiment, the electronic expansion valve is controlled to increase to a first preset opening, and the preset opening is greater than the current opening of the electronic expansion valve. In this embodiment, the first preset opening is the maximum opening of the electronic expansion valve. Based on this, it is beneficial to protect the electronic expansion valve while increasing the speed of reaching a pressure equilibrium state after the system is shut down. In other embodiments, the first preset opening may also be an opening smaller than the maximum opening of the electronic expansion valve.

[0072] In another implementation of this embodiment, the electronic expansion valve is controlled to increase its opening according to the pressure value. The opening adjustment value may be determined according to the pressure interval in which the pressure value is located, and the electronic expansion valve is controlled to increase its opening with the opening adjustment value; or the target opening of the electronic expansion valve may be determined according to the pressure value, and the electronic expansion valve may be controlled to increase its opening to the target opening for operation.

[0073] Step S22: when the pressure value is greater than the preset pressure threshold, controlling the electronic expansion valve to maintain the current opening.

[0074] When the electronic expansion valve reduces its opening, the opening adjustment value can be reduced to a preset fixed opening adjustment value, or a target opening adjustment value determined according to the actual operation of the heat pump system, or can be directly reduced to a preset fixed opening.

[0075] In this embodiment, when the pressure value is not greater than the preset pressure threshold, it indicates that the electronic expansion valve can release pressure by increasing the opening while the internal structure is not worn. At this time, the electronic expansion valve is controlled to increase the opening, which can achieve rapid unloading of the system and reach a pressure balance state; when the pressure value is greater than the preset pressure threshold, it indicates that increasing the opening of the electronic expansion valve will have a large impact on the internal structure and cause wear. At this time, the electronic expansion valve is controlled to maintain the current opening to unload, which can effectively reduce the wear of the electronic expansion valve caused by the unloading process during the shutdown process. Based on this, the service life of the electronic expansion valve is effectively improved.

[0076] In other embodiments, when the pressure value is greater than a preset pressure threshold, the electronic expansion valve may also be controlled to reduce the current opening.

[0077] Furthermore, in the present embodiment, the step of controlling the electronic expansion valve to increase its opening according to the pressure value includes: determining a pressure difference between the preset pressure threshold and the pressure value; determining an opening adjustment value according to the pressure difference; and controlling the electronic expansion valve to increase its opening with the opening adjustment value.

[0078] Different pressure difference values ​​correspond to different opening adjustment values. The opening adjustment value may include the opening adjustment amplitude, the opening adjustment ratio, the opening adjustment rate, etc. The pressure difference value is positively correlated with the opening adjustment value.

[0079] The corresponding relationship between the pressure difference and the opening adjustment value can be preset, and the corresponding relationship can include a calculation formula, a mapping relationship, an algorithm model, etc. For example, when the corresponding relationship is a calculation formula, the pressure difference can be substituted into the calculation formula to calculate the opening adjustment value. For another example, when the corresponding relationship is a mapping table, the result obtained by looking up the table by the pressure difference can be used as the opening adjustment value.

[0080] In this embodiment, the opening adjustment value determined by the pressure difference between the preset pressure threshold and the pressure value is adapted to control the electronic expansion valve to increase its opening, which is beneficial to ensure that the electronic expansion valve can achieve rapid pressure balance during the increase process while further reducing wear on its internal structure.

[0081] Furthermore, the correspondence between the pressure difference and the opening adjustment value can be fixed to one. Alternatively, more than one correspondence between the pressure difference and the opening adjustment value can be preset, and a target correspondence is determined from more than one correspondence according to the actual operation of the heat pump system, and the opening adjustment value corresponding to the pressure difference is determined based on the target correspondence. For example, the change value of the pressure difference at both ends of the electronic expansion valve before and after the heat pump system is shut down and the temperature difference between the heat exchanger temperature and the ambient temperature when the heat pump system is shut down can be obtained, and the target correspondence is determined according to the change value and the temperature difference. Different change values ​​and different temperature difference values ​​correspond to different target correspondences. Among them, the change value and the temperature difference can accurately reflect the influence of the overall pressure change trend of the system on the risk of wear of the internal structure of the electronic expansion valve during the process of increasing the opening of the electronic expansion valve. Therefore, the target correspondence is determined in combination with the change value and the temperature difference, which is conducive to rapid unloading to achieve a pressure balance state while further reducing the wear risk of the electronic expansion valve.

[0082] Further, based on any of the above embodiments, another embodiment of the control method of the electronic expansion valve of the present application is proposed. In this embodiment, referring to Figure 5 , the step S10 comprises:

[0083] Step S11, when a shutdown command of the heat pump system is received, the pressure values ​​at both ends of the electronic expansion valve are detected respectively to obtain a first pressure value and a second pressure value.

[0084] The first pressure value is detected by the first pressure sensor, and the second pressure value is detected by the second pressure sensor.

[0085] When a shutdown command of the heat pump system is received, the compressor is controlled to shut down, and the first pressure value and the second pressure value are detected when the compressor is in the shutdown state.

[0086] In this embodiment, the pressure values ​​at both ends of the electronic expansion valve can accurately reflect the impact on the internal structure of the electronic expansion valve after the opening degree of the electronic expansion valve is increased. Therefore, after the heat pump system is shut down, the opening degree of the electronic expansion valve is regulated according to the pressure values ​​at both ends of the electronic expansion valve, which is conducive to rapid pressure balance and further reduces the wear on the electronic expansion valve.

[0087] Further, in this embodiment, referring to Figure 5 , step S20 comprises:

[0088] Step S201, determining the maximum pressure value between the first pressure value and the second pressure value;

[0089] When the first pressure value is greater than the second pressure value, the first pressure value is the maximum pressure value.

[0090] When the first pressure value is less than the second pressure value, the second pressure value is the maximum pressure value.

[0091] Step S202: controlling the opening of the electronic expansion valve according to the maximum pressure value so that the heat pump system reaches a pressure balance state.

[0092] When the maximum pressure is not greater than a preset pressure threshold, the electronic expansion valve is controlled to increase its opening; when the maximum pressure is greater than the preset pressure threshold, the electronic expansion valve is controlled to maintain its current opening.

[0093] In this embodiment, the pressure at the high-pressure end of the electronic expansion valve can accurately reflect the maximum risk of wear to its internal structure. Therefore, controlling the opening of the electronic expansion valve according to the maximum pressure at both ends of the electronic expansion valve is beneficial to ensure that no matter how the refrigerant flow direction of the system changes before shutdown, the opening of the electronic expansion valve can be accurately adjusted to adapt to the wear risk after shutdown, thereby achieving system pressure balance while reducing the wear risk of the electronic expansion valve.

[0094] In other embodiments, the average of the first pressure value and the second pressure value may be determined as the average pressure, and the opening of the electronic expansion valve may be controlled according to the average pressure.

[0095] Further, based on any of the above embodiments, another embodiment of the control method of the electronic expansion valve of the present application is proposed. In this embodiment, step S10 includes: when a shutdown instruction of the heat pump system is received, obtaining the shutdown duration of the heat pump system; when the shutdown duration reaches a first preset duration, detecting a pressure value related to the operation of the electronic expansion valve in the heat pump system.

[0096] The first preset time length may be a preset fixed time length, for example, the first preset time length may be 30 seconds. The first preset time length may also be determined according to the situation before the heat pump system is shut down, for example, the first preset time length is determined according to the operating frequency of the compressor before the heat pump system is shut down.

[0097] When the shutdown duration does not reach the first preset duration, the electronic expansion valve is controlled to maintain the current opening degree.

[0098] In this embodiment, the pressure value detection is performed again after the heat pump system has been shut down for a period of time, and the opening of the electronic expansion valve is regulated according to the pressure value, which is beneficial to improving the accuracy of the pressure value in characterizing the wear risk of the electronic expansion valve, so as to further reduce the loss of the electronic expansion valve and enable the system to reach a pressure balance state.

[0099] Further, based on any of the above embodiments, another optional embodiment of the control method of the electronic expansion valve of the present application is proposed. In this embodiment, after step S20, it also includes: obtaining the shutdown time of the heat pump system; when the shutdown time reaches a second preset time, controlling the electronic expansion valve to reset to a second preset opening.

[0100] The second preset time length is greater than the first preset time length.

[0101] The second preset time length may be a preset fixed time length, for example, the first preset time length may be 120s. The second preset time length may also be determined according to the actual situation of the heat pump system, for example, according to the pressure value and the pressure change value after the electronic expansion valve opening is increased.

[0102] The second preset time duration represents that the heat pump system reaches a pressure equilibrium state after being shut down.

[0103] The second preset opening is a preset fixed opening. The second preset opening is 30% to 70% of the maximum opening. In this embodiment, when the shutdown time of the heat pump system reaches 30s, the pressure value is detected. When the detected pressure value is not greater than the preset pressure threshold, the electronic expansion valve is controlled to increase to the maximum opening of 480pls; when the detected pressure value is greater than the preset pressure threshold, the electronic expansion valve is controlled to maintain the current opening. After the electronic expansion valve increases the opening or maintains the current opening, when the shutdown time reaches 120s, the electronic expansion valve is controlled to reset to 220pls.

[0104] In this embodiment, the electronic expansion valve is reset to the second preset opening when the shutdown time reaches the second preset time. This is beneficial for avoiding the impact of sudden pressure change on the internal structure of the electronic expansion valve when the heat pump system is started again, further reducing the wear of the electronic expansion valve, and increasing the service life of the electronic expansion valve.

[0105] In this embodiment, the first preset opening degree is greater than the second preset opening degree.

[0106] In addition, an embodiment of the present invention further provides a storage medium on which a control program for an electronic expansion valve is stored. When the control program for the electronic expansion valve is executed by a processor, the relevant steps of any embodiment of the control method for an electronic expansion valve as described above are implemented.

[0107] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0108] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0109] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, including a number of instructions for a terminal device (which can be a mobile phone, computer, server, heat pump system, or network device, etc.) to execute the methods described in each embodiment of the present invention.

[0110] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A control method for an electronic expansion valve, characterized in that: The control method of the electronic expansion valve comprises the following steps: When a shutdown command of the heat pump system is received, detecting a pressure value related to the operation of the electronic expansion valve in the heat pump system; The opening of the electronic expansion valve is controlled according to the pressure value so that the heat pump system reaches a pressure balance state.

2. The control method of the electronic expansion valve according to claim 1, characterized in that: The step of controlling the opening of the electronic expansion valve according to the pressure value so that the heat pump system reaches a pressure balance state comprises: When the pressure value is not greater than a preset pressure threshold, controlling the electronic expansion valve to increase its opening; When the pressure value is greater than the preset pressure threshold, the electronic expansion valve is controlled to maintain a current opening.

3. The control method of the electronic expansion valve according to claim 2, characterized in that: The step of controlling the electronic expansion valve to increase its opening degree comprises: Controlling the electronic expansion valve to increase to a first preset opening, wherein the preset opening is greater than the current opening of the electronic expansion valve; or, The electronic expansion valve is controlled to increase its opening according to the pressure value.

4. The control method of the electronic expansion valve according to claim 3, characterized in that: The step of controlling the electronic expansion valve to increase its opening according to the pressure value comprises: determining a pressure difference between the preset pressure threshold and the pressure value; Determining an opening adjustment value according to the pressure difference; The electronic expansion valve is controlled to increase its opening degree by the opening degree adjustment value.

5. The control method of the electronic expansion valve according to claim 1, characterized in that: When a shutdown instruction of the heat pump system is received, the step of detecting a pressure value related to the operation of the electronic expansion valve in the heat pump system comprises: When a shutdown command of the heat pump system is received, the pressure values ​​at both ends of the electronic expansion valve are detected respectively to obtain a first pressure value and a second pressure value.

6. The control method of the electronic expansion valve according to claim 5, characterized in that: The step of controlling the opening of the electronic expansion valve according to the pressure value so that the heat pump system reaches a pressure balance state comprises: determining a maximum pressure value between the first pressure value and the second pressure value; The opening degree of the electronic expansion valve is controlled according to the maximum pressure value so that the heat pump system reaches a pressure balance state.

7. The control method of an electronic expansion valve according to any one of claims 1 to 6, characterized in that: When a shutdown instruction of the heat pump system is received, the step of detecting a pressure value related to the operation of the electronic expansion valve in the heat pump system comprises: When receiving a shutdown instruction of the heat pump system, obtaining the shutdown duration of the heat pump system; When the shutdown time reaches a first preset time, a pressure value related to the operation of the electronic expansion valve in the heat pump system is detected.

8. The control method of an electronic expansion valve according to any one of claims 1 to 6, characterized in that: After the step of controlling the opening of the electronic expansion valve according to the pressure value so that the heat pump system reaches a pressure balance state, the method further includes: Obtaining the downtime duration of the heat pump system; When the shutdown time reaches a second preset time, the electronic expansion valve is controlled to reset to a second preset opening.

9. A heat pump system, characterized in that: The heat pump system comprises: Electronic expansion valve; A pressure detection module, wherein the pressure detection module is disposed at at least one end of the electronic expansion valve; A control device, wherein the electronic expansion valve and the pressure detection module are both connected to the control device, and the control device comprises: a memory, a processor, and a control program for the electronic expansion valve stored in the memory and executable on the processor, wherein the control program for the electronic expansion valve, when executed by the processor, implements the steps of the control method for the electronic expansion valve as described in any one of claims 1 to 8.

10. The heat pump system according to claim 9, characterized in that: The pressure detection module includes a first pressure sensor and a second pressure sensor respectively arranged at two ends of the electronic expansion valve, and the first pressure sensor and the second pressure sensor are both connected to the control device.

11. A storage medium, characterized in that: The storage medium stores a control program for an electronic expansion valve, and when the control program for the electronic expansion valve is executed by the processor, the steps of the control method for an electronic expansion valve according to any one of claims 1 to 8 are implemented.

Images