Control method, controller, heat pump machine, related device and medium

Abstract

The application discloses a control method, a controller, a heat pump machine, related equipment and a medium. The control method is used for obtaining a corrected valve adjustment period by correcting the maintenance time length of a real-time superheat degree when the actual superheat degree of the heat pump machine reaches a target superheat degree, that is, when the heat pump machine starts to stabilize or over-adjustment occurs, and for controlling the valve adjustment according to the corrected valve adjustment period. The control scheme of the dynamic corrected valve adjustment period can reduce the valve adjustment frequency according to the stabilization of the actual superheat degree when the heat pump machine starts to stabilize or the electronic expansion valve over-adjusts. The closer the actual superheat degree is to the target superheat degree, the longer the maintenance time length is, and the larger the corrected valve adjustment period is. The control scheme can reduce over-adjustment and unstable heating problems, thereby improving the problem that the actual superheat degree of the heat pump machine frequently fluctuates around the target superheat degree.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of control of electronic expansion valves of heat pump machines, and in particular to a control method, a controller, a heat pump machine, related equipment and media. BACKGROUND

[0002] A heat pump machine can absorb heat from an outdoor environment and transfer it indoors through the circulation of refrigerant, which can reduce heating energy consumption and improve heating energy consumption ratio. A related technology proposes a control method for an electronic expansion valve. In the related technology, the control of the electronic expansion valve has the phenomenon of over-opening or over-closing, which can cause the actual superheat degree of the heat pump machine to frequently fluctuate around the target superheat degree, and the heat exchange effect of the heat pump machine is poor. SUMMARY

[0003] The technical problem solved by the present application is to provide a control method, a controller, a heat pump machine, related equipment and media to reduce the phenomenon of over-opening and over-closing of the electronic expansion valve and improve the heat exchange effect of the heat pump machine.

[0004] To solve the above technical problem, the technical solution adopted by the present application is to provide a control method for an electronic expansion valve applied to a heat pump machine, which comprises: obtaining a valve adjustment amplitude under the actual superheat degree this time; and determining whether the last actual superheat degree is not less than the target superheat degree; if the last actual superheat degree is not less than the target superheat degree and the maintenance time length of the last actual superheat degree reaches a threshold time length, correcting the maintenance time length to obtain a corrected valve adjustment period, and adjusting the valve according to the corrected valve adjustment period and the valve adjustment amplitude; if the last actual superheat degree is less than the target superheat degree or the maintenance time length of the last actual superheat degree does not reach the threshold time length, determining a valve adjustment period based on the size of the actual superheat degree this time, and adjusting the valve according to the valve adjustment period and the valve adjustment amplitude; and in response to a change in the actual superheat degree of the heat pump machine, performing again the step of obtaining the valve adjustment amplitude under the actual superheat degree this time.

[0005] In a possible implementation, the step of correcting the maintenance time length to obtain a corrected valve adjustment period specifically comprises: compensating the maintenance time length by a rated time length to obtain the corrected valve adjustment period; wherein the step of correcting the maintenance time length to obtain a corrected valve adjustment period further comprises: determining whether the maintenance time length after compensation is greater than a period threshold; if the maintenance time length after compensation is not greater than the period threshold, taking the value of the maintenance time length after compensation as the corrected valve adjustment period; and if the maintenance time length after compensation is greater than the period threshold, taking the period threshold as the corrected valve adjustment period.

[0006] In a possible implementation, the step of obtaining the valve adjustment range at the actual superheat degree this time specifically includes: obtaining a target superheat degree, an actual superheat degree this time, and a last actual superheat degree; calculating an opening degree this time, the calculation formula of the opening degree this time being Un=Un-1+Kp*(En-En-1)+(Tac÷Ti)*En; En=Qn-Q; and calculating a valve adjustment range, the calculation formula of the valve adjustment range being P=Un-Un-1; wherein Un is the opening degree of the electronic expansion valve this time, Un-1 is the opening degree of the electronic expansion valve last time, En is a difference between the actual superheat degree this time and the target superheat degree, En-1 is a difference between the last actual superheat degree and the target superheat degree, Kp is a proportional gain coefficient, Tac is a numerator of a difference proportionality coefficient, Ti is a denominator of the difference proportionality coefficient, Qn is the actual superheat degree this time, Q is the target superheat degree, and P is the valve adjustment range.

[0007] In a possible implementation, the step of adjusting the valve according to the modified valve adjustment period and the valve adjustment range specifically includes: compensating the opening degree of the electronic expansion valve by the valve adjustment range in response to the actual superheat degree being maintained for a multiple of the modified valve adjustment period; and the step of adjusting the valve according to the valve adjustment period and the valve adjustment range specifically includes:

[0008] compensating the opening degree of the electronic expansion valve by the valve adjustment range in response to the actual superheat degree being maintained for a multiple of the valve adjustment period.

[0009] In a possible implementation, the step of adjusting the valve further includes: determining whether the valve adjustment range exceeds a valve adjustment threshold; adjusting the valve according to the valve adjustment range if the valve adjustment range does not exceed the valve adjustment threshold, and adjusting the valve according to the valve adjustment threshold if the valve adjustment range exceeds the valve adjustment threshold.

[0010] In a possible implementation, the step of determining the valve adjustment period based on the actual superheat degree this time specifically includes: calculating an absolute value of a difference between the actual superheat degree this time and the target superheat degree, wherein the valve adjustment period is inversely proportional to the absolute value.

[0011] To solve the above technical problems, another technical solution adopted by the present application is to provide a controller, which controls the opening degree of the electronic expansion valve through the above control method, and the controller comprises: a calculation module, configured to obtain the valve adjustment amplitude under the actual superheat degree this time; a judgment module, configured to judge whether the last actual superheat degree is not less than the target superheat degree; a control module, if the last actual superheat degree is not less than the target superheat degree, and the maintenance time length of the last actual superheat degree reaches the threshold time length, the maintenance time length is corrected to obtain a corrected valve adjustment period, and the valve adjustment is performed according to the corrected valve adjustment period and the valve adjustment amplitude; if the last actual superheat degree is less than the target superheat degree, or the maintenance time length of the last actual superheat degree does not reach the threshold time length, the valve adjustment period is determined based on the size of the actual superheat degree this time, and the valve adjustment is performed according to the valve adjustment period and the valve adjustment amplitude; in response to the change of the actual superheat degree of the heat pump machine, the step of obtaining the valve adjustment amplitude under the actual superheat degree this time is performed again.

[0012] To solve the above technical problems, another technical solution adopted by the present application is to provide a heat pump machine, which controls the opening degree of the electronic expansion valve through the above control method.

[0013] To solve the above technical problems, another technical solution adopted by the present application is to provide an electronic device, which comprises: a processor; a memory connected to the processor, configured to store a computer program executable on the processor; wherein the processor implements the above control method when executing the computer program.

[0014] To solve the above technical problems, another technical solution adopted by the present application is to provide a computer readable storage medium, and the computer program is executed by the processor to implement the above control method.

[0015] The beneficial effects of the present application are: different from the prior art, the present application provides a control method of an electronic expansion valve of a heat pump machine, which obtains a corrected valve adjustment period by correcting the maintenance time length of the real-time superheat degree when the actual superheat degree of the heat pump machine reaches the target superheat degree, i.e. when the heat pump machine starts to stabilize or over-adjustment occurs, and controls the valve adjustment according to the corrected valve adjustment period. The control scheme of the dynamic corrected valve adjustment period can reduce the valve adjustment frequency according to the stabilization of the actual superheat degree when the heat pump machine starts to stabilize or the electronic expansion valve over-adjusts. The closer the actual superheat degree is to the target superheat degree, the longer the maintenance time length is, and the larger the corrected valve adjustment period is. The problems of over-adjustment and unstable heating can be reduced, thereby improving the problem that the actual superheat degree of the heat pump machine frequently fluctuates around the target superheat degree. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative effort based on these drawings.

[0017] Figure 1 is a structural schematic diagram of an embodiment of the heat pump machine provided in the present application;

[0018] Figure 2 is a flow schematic diagram of an embodiment of the control method of the electronic expansion valve of the heat pump machine provided in the present application;

[0019] Figure 3 is Figure 2 is a flow schematic diagram of an embodiment of S11 in the method provided in the present application;

[0020] Figure 4 is a structural block diagram of an embodiment of the controller provided in the present application;

[0021] Figure 5 is a structural schematic block diagram of an embodiment of the electronic device provided in the present application;

[0022] Figure 6 is a structural schematic block diagram of an embodiment of the computer readable storage medium provided in the present application. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present application will be described clearly and completely in the following with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort fall within the scope of protection of the present application.

[0024] The terms used in the embodiments of the present application are only for the purpose of describing the specific embodiments, and are not intended to limit the present application. The singular forms "a", "an" and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless otherwise clearly indicated. "Multiple" generally includes at least two, but does not exclude the case of including at least one.

[0025] It should be understood that the term "and / or" used herein is only to describe the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0026] It should be understood that the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without more limitations, an element defined by the statement "comprising" does not exclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0027] In the related art, the opening degree control of the electronic expansion valve has the problem of over-opening or over-closing. In particular, when the ambient temperature is low, the opening degree of the electronic expansion valve is small, and the actual superheat degree of the heat pump machine is close to the target superheat degree, the adjustment of the valve is prone to appear obvious lag in the change of the real-time superheat degree, causing the actual superheat degree of the heat pump machine to frequently fluctuate around the target superheat degree, and the heat exchange effect of the heat pump machine is poor.

[0028] Based on the above problems, the present application provides a control method, a controller, a heat pump machine, related equipment and media for controlling the electronic expansion valve of the heat pump machine. The valve adjustment period can be dynamically adjusted according to the change of the actual superheat degree, the problem of over-opening and over-closing of the electronic expansion valve can be reduced, and the heat exchange effect of the heat pump machine can be improved.

[0029] The control method, the controller, the heat pump machine, the related equipment and the media for controlling the electronic expansion valve of the heat pump machine provided by the present application will be described in detail below in combination with the drawings and embodiments.

[0030] The present application provides a control method for the electronic expansion valve of a heat pump machine, which is used to adjust the opening degree of the electronic expansion valve of the heat pump machine, so that the real-time superheat degree of the heat pump machine is a proper value, the heat exchange efficiency between the heat pump machine and the environment is high, and the heat exchange effect of the heat pump machine is improved. Please refer to Figure 1 , Figure 1 is a structural schematic diagram of an embodiment of the heat pump machine provided by the present application. In one specific embodiment, the heat pump machine (not marked) comprises a four-way valve 11, a compressor 12, an electronic expansion valve 15, an evaporator 13 located outdoors, and a condenser 14 located indoors.

[0031] The compressor 12 is used to compress the low-temperature and low-pressure gaseous refrigerant to change it into high-temperature and high-pressure gaseous refrigerant. The four-way valve 11 is used to switch the state and change the flow direction of the refrigerant, and plays a role of switching the refrigeration and heating modes in the heat pump machine. When the refrigerant cycle is in the refrigeration cycle, the four-way valve 11 makes the refrigerant flow to the evaporator 13. When the refrigerant cycle is in the heating cycle, the four-way valve 11 changes the internal communication state, so that the refrigerant first flows through the condenser 14 and then flows to the evaporator 13.

[0032] The electronic expansion valve 15 is used to adjust the flow of refrigerant in the heat pump cycle path, so that in different environments, by adjusting the electronic expansion valve 15, the heat pump is in a reasonable value of real-time superheat, which can improve the heat exchange capacity and improve the heat exchange efficiency. Among them, when the real-time superheat is too high, the opening of the electronic expansion valve 15 can be increased to increase the refrigerant flow, so as to reduce the return gas temperature of the compressor 12, reduce the real-time superheat, and reduce the problem of overheating of the compressor 12. When the real-time superheat is too low, the opening of the electronic expansion valve 15 can be reduced to reduce the refrigerant flow, thereby improving the energy efficiency and reducing energy waste.

[0033] In some embodiments, the heat pump in the embodiment of the application further comprises a controller (not indicated), which is connected with the compressor 12, the four-way valve 11, the electronic expansion valve 15 and the like of the heat pump. The execution subject of the control method of the electronic expansion valve 15 of the heat pump in the embodiment is the controller.

[0034] In order to improve the problem of over-opening or over-closing of the opening control of the electronic expansion valve, especially when the environmental temperature is low, the opening of the electronic expansion valve is small, and the actual superheat of the heat pump is close to the target superheat, the adjustment of the valve will appear obvious lag in the change of the real-time superheat, causing the actual superheat of the heat pump to frequently fluctuate around the target superheat, and the heat exchange effect of the heat pump is poor. The application provides a control method of an electronic expansion valve of a heat pump, a controller, a heat pump, related equipment and media to solve the above technical problems.

[0035] Please refer to Figure 2 , Figure 2 is a flowchart of an embodiment of the control method of the electronic expansion valve of the heat pump of the application. The method is used to adjust the opening of the electronic expansion valve. In a specific embodiment, the method comprises:

[0036] S11: obtaining the valve adjustment amplitude under the actual superheat this time; determining whether the last actual superheat is not less than the target superheat.

[0037] In S11, the step of obtaining the valve adjustment amplitude under the actual superheat this time is performed first, and then the step of determining whether the last actual superheat is not less than the target superheat is performed.

[0038] If the last actual superheat is not less than the target superheat, S12 is performed; otherwise, S14 is performed.

[0039] The step is performed when the real-time superheat degree of the heat pump machine changes. When the valve adjustment amplitude is positive, the opening of the electronic expansion valve is increased during valve adjustment; when the valve adjustment amplitude is negative, the opening of the electronic expansion valve is decreased during valve adjustment. When the actual superheat degree is less than the target superheat degree, the valve adjustment amplitude is negative; when the actual superheat degree is greater than the target superheat degree, the valve adjustment amplitude is positive. The actual superheat degree tends to the target superheat degree through the valve adjustment amplitude. In some embodiments, the absolute value of the valve adjustment amplitude is positively correlated with the absolute value of the difference between the actual superheat degree and the target superheat degree.

[0040] In some embodiments, the step of calculating the valve adjustment amplitude can specifically include: obtaining the target superheat degree, the current actual superheat degree, and the last actual superheat degree; calculating the current opening, the calculation formula of the current opening being Un=Un-1+Kp*(En-En-1)+(Tac÷Ti)*En; En=Qn-Q; calculating the valve adjustment amplitude, the calculation formula of the valve adjustment amplitude being P=Un-Un-1; wherein Un is the opening of the electronic expansion valve, Un-1 is the opening of the electronic expansion valve in the last time, En is the difference between the current actual superheat degree and the target superheat degree, En-1 is the difference between the last actual superheat degree and the target superheat degree, Kp is a proportional gain coefficient, Tac is the numerator of the difference proportional coefficient, Ti is the denominator of the difference proportional coefficient, Qn is the current actual superheat degree, Q is the target superheat degree, and P is the valve adjustment amplitude.

[0041] S12: determining whether the maintenance duration of the last actual superheat degree reaches a threshold duration.

[0042] If the maintenance duration of the last actual superheat degree reaches the threshold duration, S131 is performed; if the maintenance duration of the last actual superheat degree does not reach the threshold duration, S132 is performed.

[0043] In the embodiment, to reduce the problem of overheating of the compressor when the heat pump machine starts, the electronic expansion valve is at a larger opening value when the equipment starts, which can reduce the problem of overheating of the compressor and avoid equipment failure. During the working process of the heat pump machine, the valve is adjusted according to the change of the actual superheat degree, the opening of the electronic expansion valve is gradually reduced, the actual superheat degree of the heat pump machine is gradually increased, the actual superheat degree gradually tends to the target superheat degree, and the heating effect is improved. When the last actual superheat degree is not less than the target superheat degree and the maintenance duration can reach the threshold duration, it is reflected that the heat pump machine has started to stabilize or the electronic expansion valve has started to be over-adjusted.

[0044] S132: determining the valve adjustment period based on the size of the current actual superheat degree, and adjusting the valve according to the valve adjustment period and the valve adjustment amplitude.

[0045] The size of the valve adjustment period is related to the size of the actual superheat degree. The step of determining the valve adjustment period based on the size of the actual superheat degree can include: calculating the absolute value of the difference between the actual superheat degree and the target superheat degree, wherein the size of the valve adjustment period is inversely proportional to the absolute value. Specifically, the larger the absolute value of the difference between the actual superheat degree and the target superheat degree, the farther the heat pump machine is from the target superheat degree, and the smaller the valve adjustment period, which can increase the valve adjustment frequency of the electronic expansion valve and enable higher-frequency valve adjustment when the heat pump machine is farther from the target superheat degree, so that the heat pump machine can approach the target superheat degree more quickly. The smaller the absolute value of the difference between the actual superheat degree and the target superheat degree, the closer the heat pump machine is to the target superheat degree, and the larger the valve adjustment period, which can reduce the valve adjustment frequency of the electronic expansion valve and enable lower-frequency valve adjustment when the heat pump machine is closer to the target superheat degree, so that the problem of over-adjustment can be reduced, the real-time superheat degree of the heat pump machine can be stabilized near the real-time superheat degree, and frequent fluctuations can be reduced.

[0046] For example, in a specific application scenario, the size of the valve adjustment period can have the following relationship with the size of the actual superheat degree: when the difference between the actual superheat degree and the target superheat degree is not less than 3 degrees Celsius, the valve adjustment period is a first value; when the difference between the actual superheat degree and the target superheat degree is less than 3 degrees Celsius and not less than 1 degree Celsius, the valve adjustment period is a second value; when the difference between the actual superheat degree and the target superheat degree is less than 1 degree Celsius and not less than -1 degree Celsius, the valve adjustment period is a third value; when the difference between the actual superheat degree and the target superheat degree is less than -1 degree Celsius and not less than -2 degrees Celsius, the valve adjustment period is a fourth value; and when the difference between the actual superheat degree and the target superheat degree is less than -2 degrees Celsius, the valve adjustment period is a fifth value, wherein the first value is less than the second value, the second value is less than the third value, the fifth value is less than the fourth value, and the fourth value is less than the third value. In a specific embodiment, the first value is 20 seconds, the second value is 25 seconds, the third value is 30 seconds, the fourth value is 25 seconds, and the fifth value is 20 seconds.

[0047] In some embodiments, the step of adjusting the valve according to the valve adjustment period and the valve adjustment amplitude specifically includes: in response to the maintenance time length of the actual superheat degree reaching a multiple of the valve adjustment period, compensating the opening degree of the electronic expansion valve by the valve adjustment amplitude. For example, if the valve adjustment amplitude is 1 and the valve adjustment period is 20 seconds, the maintenance time length of the heat pump machine at the current actual superheat degree is counted in real time. When the maintenance time length reaches 20 seconds, the opening degree of the electronic expansion valve is increased by 1, and when the maintenance time length reaches 40 seconds, the opening degree of the electronic expansion valve is again increased by 1, until the real-time superheat degree of the heat pump machine changes.

[0048] S1321: In response to the actual superheat degree of the heat pump machine changing, the step of obtaining the valve adjustment amplitude at the actual superheat degree is performed again.

[0049] S131: correct the maintaining time length to obtain a corrected valve adjusting period, and adjust the valve according to the corrected valve adjusting period and the valve adjusting amplitude.

[0050] In the step, the threshold time length is a preset time length, and preferably greater than the valve adjusting period. When the last actual superheat degree is not less than the target superheat degree and the maintaining time length reaches the threshold time length, it is reflected that the heat pump machine has started to stabilize or the electronic expansion valve has started to over-adjust. If the valve continues to be adjusted based on the valve adjusting period, over-adjustment and large real-time superheat degree fluctuation are likely to occur. Therefore, the step is performed when the last actual superheat degree is not less than the target superheat degree and the maintaining time length of the last actual superheat degree reaches the threshold time length. The corrected valve adjusting period obtained by correcting the maintaining time length is greater than the valve adjusting period. When the heat pump machine starts to stabilize or the electronic expansion valve starts to over-adjust, the valve adjusting frequency is reduced, over-adjustment and unstable heating are reduced, and the problem that the actual superheat degree of the heat pump machine frequently fluctuates around the target superheat degree is improved. On the other hand, in the step, the maintaining time length is corrected to obtain the corrected valve adjusting period. The size of the corrected valve adjusting period is related to the maintaining time length of the last actual superheat degree. The greater the maintaining time length of the last actual superheat degree, the greater the corrected valve adjusting period. The smaller the maintaining time length, the smaller the corrected valve adjusting period. It is easy to understand that the greater the maintaining time length of the last actual superheat degree, the smaller the problem of over-adjustment of the heat pump machine or the closer the electronic expansion valve to the ideal opening degree. The valve is adjusted by a larger corrected valve adjusting period to reduce the problem of over-adjustment and stabilize the heating of the heat pump machine. The smaller the maintaining time length of the last actual superheat degree, the greater the problem of over-adjustment of the heat pump machine. The valve is adjusted by a smaller corrected valve adjusting period to make the electronic expansion valve more quickly approach the ideal opening degree and stabilize the heating of the heat pump machine. In a specific embodiment, the threshold time length can be 30 seconds. In some other embodiments, the threshold time length can also be 35 seconds, 40 seconds, and the like.

[0051] In some embodiments, the step of correcting the maintaining time length to obtain the corrected valve adjusting period specifically includes compensating the maintaining time length by a rated time length to obtain the corrected valve adjusting period. For example, in a specific application scenario, the rated time length is set to 10 seconds. If the maintaining time length of the last actual superheat degree is 50 seconds, the corrected valve adjusting period is 60 seconds. If the maintaining time length of the last actual superheat degree is 60 seconds, the corrected valve adjusting period is 70 seconds. Further, in some preferred embodiments, the step of correcting the maintaining time length to obtain the corrected valve adjusting period further includes judging whether the maintaining time length after compensation is greater than a period threshold. If the maintaining time length after compensation is not greater than the period threshold, the value of the maintaining time length after compensation is taken as the corrected valve adjusting period. If the maintaining time length after compensation is greater than the period threshold, the period threshold is taken as the corrected valve adjusting period. Specifically, the period threshold can be 180 seconds. In some other embodiments, the period threshold can also be 170 seconds, 190 seconds, 200 seconds, and the like.

[0052] In some embodiments, the step of adjusting the valve according to the modified valve adjustment period and the valve adjustment value specifically comprises: compensating the opening degree of the electronic expansion valve by the valve adjustment value in response to the maintenance time length of the actual superheat reaching a multiple of the modified valve adjustment period. Specifically, for example, if the valve adjustment value is 1 and the modified valve adjustment period is 60 seconds, the maintenance time length of the actual superheat of the heat pump machine at the current actual superheat is counted in real time. When the maintenance time length reaches 60 seconds, the opening degree of the electronic expansion valve is increased by 1, and when the maintenance time length reaches 120 seconds, the opening degree of the electronic expansion valve is increased by 1 again, until the real-time superheat of the heat pump machine changes.

[0053] S1311: In response to the actual superheat of the heat pump machine changing, the step of obtaining the valve adjustment value at the current actual superheat is performed again.

[0054] Further, in some embodiments, the step of adjusting the valve further comprises: determining whether the valve adjustment value exceeds a valve adjustment threshold value; if the valve adjustment value does not exceed the valve adjustment threshold value, adjusting the valve according to the valve adjustment value, and if the valve adjustment value exceeds the valve adjustment threshold value, adjusting the valve according to the valve adjustment threshold value. For example, in a specific application scenario, the value range of the valve adjustment value is set to -1 to 1, when the calculated valve adjustment value is -2, the valve adjustment threshold value -1 is used for valve adjustment, when the calculated valve adjustment value is 1, the valve adjustment value 1 is used for valve adjustment, and when the calculated valve adjustment value is 3, the valve adjustment threshold value 1 is used for valve adjustment. The above can reduce the problem that the valve adjustment value is too large and the electronic expansion valve is easily over-adjusted. In some other embodiments, the value range of the valve adjustment value can also be -1 to 2, -2 to 2, etc.

[0055] S14: Determine the valve adjustment period based on the size of the current actual superheat, and adjust the valve according to the valve adjustment period and the valve adjustment value.

[0056] S15: In response to the actual superheat of the heat pump machine changing, the step of obtaining the valve adjustment value at the current actual superheat is performed again.

[0057] After S14 is performed, S15 is performed.

[0058] Please refer to Figure 3 , Figure 3 is Figure 2 the flowchart of an embodiment of S11 in

[0059] S21: Determine whether the last actual superheat is not less than the target superheat.

[0060] If the last actual superheat is not less than the target superheat, S12 is performed; if the last actual superheat is less than the target superheat, S22 is performed.

[0061] S12: In response to the previous actual superheat degree being not less than the target superheat degree, determining whether a maintenance duration of the previous actual superheat degree reaches a threshold duration.

[0062] Please refer to S12 described above, which will not be repeated here.

[0063] S22: Determining a valve adjustment period based on the size of the current actual superheat degree, and adjusting the valve according to the valve adjustment period and a valve adjustment amplitude.

[0064] The size of the valve adjustment period is related to the size of the actual superheat degree. The step of determining the valve adjustment period based on the size of the current actual superheat degree can include: calculating an absolute value of a difference between the current actual superheat degree and the target superheat degree, wherein the size of the valve adjustment period is inversely proportional to the absolute value. Specifically, the larger the absolute value of the difference between the actual superheat degree and the target superheat degree, the farther the heat pump machine is from the target superheat degree, which makes the valve adjustment period smaller, can improve the valve adjustment frequency of the electronic expansion valve, and can perform higher frequency valve adjustment when the heat pump machine is farther from the target superheat degree, so that the heat pump machine can approach the target superheat degree more quickly. The smaller the absolute value of the difference between the actual superheat degree and the target superheat degree, the closer the heat pump machine is to the target superheat degree, which makes the valve adjustment period larger, can reduce the valve adjustment frequency of the electronic expansion valve, and can perform lower frequency valve adjustment when the heat pump machine is closer to the target superheat degree, which can reduce the problem of over-adjustment, so that the real-time superheat degree of the heat pump machine can be stabilized near the real-time superheat degree, and frequent fluctuations can be reduced.

[0065] Unlike the prior art, the present application provides a control method for an electronic expansion valve of a heat pump machine. When the actual superheat degree of the heat pump machine reaches the target superheat degree, i.e., when the heat pump machine starts to stabilize or over-adjustment occurs, the control method corrects the maintenance duration of the real-time superheat degree to obtain a corrected valve adjustment period, and controls the valve adjustment according to the corrected valve adjustment period. The control scheme of dynamically correcting the valve adjustment period can reduce the valve adjustment frequency according to the stabilization of the actual superheat degree when the heat pump machine starts to stabilize or the electronic expansion valve over-adjusts. The closer the actual superheat degree is to the target superheat degree, the longer the maintenance duration, and the larger the corrected valve adjustment period, which can reduce the problems of over-adjustment and unstable heating, thereby improving the problem of frequent fluctuations of the actual superheat degree of the heat pump machine near the target superheat degree.

[0066] Finally, in a specific application scenario, please refer to Table 1:

[0067] Table 1

[0068]

[0069] The above Table 1 is a specific control process, the parameters of the heat pump machine change. In this application scenario, the valve threshold value is in the range of -1 to 1, the initial opening of the electronic expansion valve is 90, when the difference between the actual superheat and the target superheat is not less than 3 degrees Celsius, the valve period is the first value, when the difference between the actual superheat and the target superheat is less than 3 degrees Celsius and not less than 1 degree Celsius, the valve period is the second value, when the difference between the actual superheat and the target superheat is less than 1 degree Celsius and not less than -1 degree Celsius, the valve period is the third value, when the difference between the actual superheat and the target superheat is less than -1 degree Celsius and not less than -2 degrees Celsius, the valve period is the fourth value. When the difference between the actual superheat and the target superheat is less than -2 degrees Celsius, the valve period is the fifth value, wherein the first value is less than the second value, the second value is less than the third value, the fifth value is less than the fourth value, and the fourth value is less than the third value. In a specific embodiment, the first value is 20 seconds, the second value is 25 seconds, the third value is 30 seconds, the fourth value is 25 seconds, and the fifth value is 20 seconds. The threshold duration is 30 seconds.

[0070] As shown in the first column of the above table, the real-time superheat is less than the target superheat, the valve period is determined based on the size of the actual superheat, and the valve is adjusted according to the valve period and the valve amplitude. The calculated valve amplitude is -1, the difference between the real-time superheat and the target superheat is -3, the valve period is 20 seconds, the actual superheat maintenance duration is 40 seconds, the valve is adjusted twice, and the opening is reduced from 90 to 88. As shown in the second to fourth columns of the above table, the actual superheat maintenance duration in the second to fourth columns is less than the valve period, and the valve is not adjusted. As shown in the fifth column, the actual superheat is greater than the target superheat, but the maintenance duration of the last actual superheat does not reach the threshold duration, the valve period is still determined based on the size of the actual superheat, and the valve is adjusted according to the valve period and the valve amplitude. The calculated valve period is 25 seconds, the valve amplitude is 1, the maintenance duration reaches twice the valve period, the valve is adjusted twice, and the final opening is increased from 88 to 90. As shown in the sixth column, the actual superheat is greater than the target superheat, and the maintenance duration of the last actual superheat reaches the threshold duration, the maintenance duration of the last actual superheat is corrected to obtain a corrected valve period, and the valve is adjusted according to the corrected valve period and the valve amplitude. The calculated valve amplitude is -1, and the corrected valve period is 60 seconds. Since the maintenance duration is 60 seconds, the valve is adjusted once, and the final opening is reduced from 90 to 89. The seventh column is similar to the sixth column, which will not be described here.

[0071] The control method described above, when the actual superheat degree of the heat pump machine reaches the target superheat degree, that is, when the heat pump machine starts to stabilize or over-regulation occurs, the maintenance time of the real-time superheat degree is corrected to obtain a corrected valve adjustment period, and the valve adjustment is controlled according to the corrected valve adjustment period. The control scheme of the dynamic correction of the valve adjustment period can reduce the valve adjustment frequency according to the stabilization of the actual superheat degree when the heat pump machine starts to stabilize or the electronic expansion valve over-regulates. The closer the actual superheat degree is to the target superheat degree, the longer the maintenance time is, and the larger the corrected valve adjustment period is. This can reduce over-regulation and unstable heating problems, thereby improving the problem of frequent fluctuations of the actual superheat degree of the heat pump machine around the target superheat degree.

[0072] Correspondingly, the application also provides a heat pump machine, which is controlled by the control method described in the above embodiments.

[0073] Please refer to Figure 4 , Figure 4 is a structural block diagram of an embodiment of the controller of the application. Correspondingly, the application also provides a controller 1000, which controls the opening degree of the electronic expansion valve by the control method described above. The controller 1000 includes a calculation module 3000, a control module 2000, and a judgment module 4000. The calculation module 3000 is configured to obtain a valve adjustment amplitude under the actual superheat degree of this time; the judgment module 4000 is configured to judge whether the actual superheat degree of the last time is not less than the target superheat degree; and the control module 2000 is configured to, when the actual superheat degree of the last time is not less than the target superheat degree and the maintenance time of the actual superheat degree of the last time reaches a threshold time length, correct the maintenance time to obtain a corrected valve adjustment period, and adjust the valve according to the corrected valve adjustment period and the valve adjustment amplitude; when the actual superheat degree of the last time is less than the target superheat degree or the maintenance time of the actual superheat degree of the last time does not reach the threshold time length, determine a valve adjustment period based on the size of the actual superheat degree of this time, and adjust the valve according to the valve adjustment period and the valve adjustment amplitude; and in response to a change in the actual superheat degree of the heat pump machine, execute again the step of obtaining the valve adjustment amplitude under the actual superheat degree of this time.

[0074] In some embodiments, the step of correcting the maintenance time to obtain a corrected valve adjustment period specifically includes: compensating the maintenance time by a rated time length to obtain the corrected valve adjustment period; and the step of correcting the maintenance time to obtain a corrected valve adjustment period further includes: judging whether the maintenance time after compensation is greater than a period threshold value, if the maintenance time after compensation is not greater than the period threshold value, taking the value of the maintenance time after compensation as the corrected valve adjustment period, and if the maintenance time after compensation is greater than the period threshold value, taking the period threshold value as the corrected valve adjustment period.

[0075] In some embodiments, the step of obtaining the valve adjustment range at the actual overheat degree this time comprises: obtaining a target overheat degree, an actual overheat degree this time, and an actual overheat degree last time; calculating an opening degree this time, wherein the calculation formula of the opening degree this time is Un=Un-1+Kp*(En-En-1)+(Tac÷Ti)*En; En=Qn-Q; and calculating the valve adjustment range, wherein the calculation formula of the valve adjustment range is P=Un-Un-1; wherein Un is the opening degree of the electronic expansion valve this time, Un-1 is the opening degree of the electronic expansion valve last time, En is the difference between the actual overheat degree this time and the target overheat degree, En-1 is the difference between the actual overheat degree last time and the target overheat degree, Kp is a proportional gain coefficient, Tac is the numerator of a difference proportion coefficient, Ti is the denominator of the difference proportion coefficient, Qn is the actual overheat degree this time, Q is the target overheat degree, and P is the valve adjustment range.

[0076] In some embodiments, the step of adjusting the valve according to the modified valve adjustment period and the valve adjustment range comprises: compensating the opening degree of the electronic expansion valve by the valve adjustment range in response to the maintenance time length of the actual overheat degree reaching a multiple of the modified valve adjustment period; and the step of adjusting the valve according to the valve adjustment period and the valve adjustment range comprises: compensating the opening degree of the electronic expansion valve by the valve adjustment range in response to the maintenance time length of the actual overheat degree reaching a multiple of the valve adjustment period.

[0077] In some embodiments, the step of adjusting the valve further comprises: determining whether the valve adjustment range exceeds a valve adjustment threshold; if the valve adjustment range does not exceed the valve adjustment threshold, adjusting the valve according to the valve adjustment range; and if the valve adjustment range exceeds the valve adjustment threshold, adjusting the valve according to the valve adjustment threshold.

[0078] In some embodiments, the step of determining the valve adjustment period based on the actual overheat degree this time comprises: calculating an absolute value of the difference between the actual overheat degree this time and the target overheat degree, wherein the valve adjustment period is inversely proportional to the absolute value.

[0079] Correspondingly, the present application also provides an electronic device, please refer to Figure 5 , Figure 5 is a structural schematic block diagram of an embodiment of the electronic device of the present application. The electronic device 200 comprises a processor 220 and a memory 210. The memory 210 is connected to the processor 220 and is used for storing a computer program that can run on the processor 220; wherein the processor 220 implements the control method of any one of the above embodiments when executing the computer program.

[0080] The present application also provides a computer readable storage medium, please refer to Figure 6 , Figure 6is a structural schematic block diagram of an embodiment of the computer readable storage medium of the present application. The computer readable storage medium 30 of the present application stores the computer program 300, and the computer program 300 is executed by the processor to implement the control method of any of the above embodiments.

[0081] The computer readable storage medium 30 can be specifically a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, or a medium capable of storing the computer program 300, or a server storing the computer program 300, which can send the stored computer program 300 to other devices for running, or can run the stored computer program 300.

[0082] In several embodiments provided in the present application, it should be understood that the disclosed method, device and apparatus can be implemented in other manners. For example, the above-described device and apparatus embodiments are merely illustrative, and the division of the modules or units can be different, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection can be indirect coupling or communication connection through some interfaces, devices or units, and can be electrical, mechanical or other forms.

[0083] The units described as separate components can or can not be physically separate, and the components displayed as units can or can not be physical units, that is, they can be located in one place, or can be distributed on a plurality of network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the present embodiment.

[0084] In addition, the functional units in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The above integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0085] When the integrated units are implemented in the form of software function units and sold or used as independent products, the integrated units can be stored in a computer readable storage medium. Based on such an understanding, the technical solutions of the present application, essentially or in other words, the part that contributes to the prior art or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to perform all or part of the steps of the methods of the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various media that can store program codes.

Claims

1. A control method for an electronic expansion valve, applied to a heat pump, characterized in that: The control method includes: Get the valve adjustment amplitude under the actual superheat; Determine whether the previous actual superheat is not less than the target superheat; If the last actual superheat is not less than the target superheat, and the duration of the maintenance of the last actual superheat reaches a threshold duration, the maintenance duration is corrected to obtain a corrected valve regulation cycle. The step of correcting the maintenance duration to obtain the corrected valve regulation cycle specifically includes: compensating the maintenance duration by a rated duration to obtain the corrected valve regulation cycle; wherein, the step of correcting the maintenance duration to obtain the corrected valve regulation cycle also includes: determining whether the compensated maintenance duration is greater than a cycle threshold; if the compensated maintenance duration is not greater than the cycle threshold, using the compensated maintenance duration as the corrected valve regulation cycle; if the compensated maintenance duration is greater than the cycle threshold, using the cycle threshold as the corrected valve regulation cycle; and regulating the valve according to the corrected valve regulation cycle and the valve regulation amplitude. If the previous actual superheat is less than the target superheat, or the duration of the previous actual superheat does not reach the threshold duration, determining the valve regulation period based on the current actual superheat, wherein the step of determining the valve regulation period based on the current actual superheat comprises: calculating the absolute value of the difference between the current actual superheat and the target superheat, wherein the valve regulation period is inversely proportional to the absolute value; and regulating the valve according to the valve regulation period and the valve regulation amplitude; In response to a change in the actual superheat of the heat pump, the step of obtaining the valve adjustment amplitude at the current actual superheat is performed again.

2. The control method according to claim 1, characterized in that: The step of obtaining the valve adjustment amplitude under the actual superheat degree specifically includes: Get the target superheat, the current actual superheat, and the previous actual superheat; Calculate the current opening, the calculation formula of the current opening is: The n =U n-1 +Kp*(E n -E n-1 )+(Tac÷Ti)*E n ; E n =Q n -Q; Calculate the valve adjustment amplitude. The calculation formula for the valve adjustment amplitude is: P=U n -U n-1 ; Among them, U n is the opening degree of the electronic expansion valve, U n-1 is the opening degree of the last electronic expansion valve, E n is the difference between the actual superheat and the target superheat, E n-1 is the difference between the previous actual superheat and the target superheat, Kp is the proportional gain coefficient, Tac is the numerator of the difference proportional coefficient, Ti is the denominator of the difference proportional coefficient, Q n is the actual superheat, Q is the target superheat, and P is the valve adjustment amplitude.

3. The control method according to claim 1, wherein: The step of regulating the valve according to the corrected valve regulating period and the valve regulating amplitude specifically includes: In response to the maintenance time of the actual superheat reaching a multiple of the corrected valve regulating period, compensating the opening of the electronic expansion valve by the valve regulating amplitude; The step of regulating the valve according to the valve regulating period and the valve regulating amplitude specifically includes: In response to the maintenance time of the actual superheat reaching a multiple of the valve regulation period, the opening of the electronic expansion valve is compensated by the valve regulation amplitude.

4. The control method according to claim 3, characterized in that: The step of regulating the valve further includes: Determine whether the valve adjustment amplitude exceeds the valve adjustment threshold; if the valve adjustment amplitude does not exceed the valve adjustment threshold, adjust the valve according to the valve adjustment amplitude; if the valve adjustment amplitude exceeds the valve adjustment threshold, adjust the valve according to the valve adjustment threshold.

5. A controller, characterized in that: The controller controls the opening of the electronic expansion valve by the control method according to any one of claims 1 to 4, and the controller includes: A calculation module, the calculation module is used to obtain the valve adjustment amplitude under the actual superheat; a judgment module, the judgment module being used to judge whether the previous actual superheat degree is not less than the target superheat degree; The control module corrects the maintenance time to obtain a corrected valve regulation period if the previous actual superheat is not less than the target superheat and the maintenance time of the previous actual superheat reaches a threshold time, and regulates the valve according to the corrected valve regulation period and the valve regulation amplitude; if the previous actual superheat is less than the target superheat or the maintenance time of the previous actual superheat does not reach the threshold time, determines the valve regulation period based on the magnitude of the current actual superheat, and regulates the valve according to the valve regulation period and the valve regulation amplitude; and in response to a change in the actual superheat of the heat pump, executes again the step of obtaining the valve regulation amplitude for the current actual superheat.

6. A heat pump machine, characterized in that: The heat pump controls the opening of the electronic expansion valve by the control method according to any one of claims 1 to 4.

7. An electronic device, characterized in that: include: processor; A memory, connected to the processor, for storing a computer program that can be run on the processor; wherein, when the processor executes the computer program, the control method according to any one of claims 1 to 4 is implemented.

8. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the control method according to any one of claims 1 to 4 is implemented.

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