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

Abstract

The invention discloses a control method, a controller, a heat pump machine, related equipment and a medium. According to the control method, when the actual superheat degree of the heat pump machine reaches the target superheat degree, that is, when the heat pump machine starts to be stable or overregulation occurs, the corrected valve regulation period is obtained by correcting the maintaining duration of the real-time superheat degree, valve regulation is controlled according to the corrected valve regulation period, and according to the control scheme for dynamically correcting the valve regulation period, the valve regulation efficiency is improved. When the heat pump starts to be stable or the electronic expansion valve is over-adjusted, the valve adjusting frequency can be reduced according to the stability condition of the actual superheat degree, the closer the actual superheat degree is to the target superheat degree, the longer the maintaining time is, the longer the valve adjusting correction period is, the problems of over-adjustment and unstable heating can be reduced, and the heating efficiency is improved. Therefore, the problem that the actual superheat degree of the heat pump machine frequently fluctuates near the target superheat degree can be solved.

Description

Technical Field

[0001] This application relates to the technical field of the control of electronic expansion valves of heat pump machines, and particularly to a control method, a controller, a heat pump machine, related equipment and a medium. Background Art

[0002] A heat pump machine can absorb heat from the outdoor environment through the circulation of refrigerant and transfer it indoors, which can reduce the heating energy consumption and improve the heating energy consumption ratio. Related technologies propose a control method for an electronic expansion valve. In related technologies, there are phenomena of over-opening or over-closing in the control of the electronic expansion valve, which will cause the actual superheat degree of the heat pump machine to fluctuate frequently near the target superheat degree, and the heat exchange effect of the heat pump machine is poor. Summary of the Invention

[0003] The main technical problem to be solved by this application is to provide a control method, a controller, a heat pump machine, related equipment and a medium to reduce the phenomena 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 this application is to provide a control method for an electronic expansion valve, which is applied to a heat pump machine. The control method includes: obtaining the valve adjustment amplitude at the current actual superheat degree; and judging whether the previous actual superheat degree is not less than the target superheat degree. If the previous actual superheat degree is not less than the target superheat degree and the maintenance duration of the previous actual superheat degree reaches the threshold duration, correcting the maintenance duration 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 previous actual superheat degree is less than the target superheat degree, or the maintenance duration of the previous actual superheat degree does not reach the threshold duration, 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; in response to the change of the actual superheat degree of the heat pump machine, executing the step of obtaining the valve adjustment amplitude at the current actual superheat degree again.

[0005] In a possible implementation manner, the step of correcting the maintenance duration to obtain a corrected valve adjustment period specifically includes: compensating the maintenance duration by a fixed duration to obtain the corrected valve adjustment period; wherein, the step of correcting the maintenance duration to obtain a corrected valve adjustment period further includes: judging whether the compensated maintenance duration is greater than the period threshold. If the compensated maintenance duration is not greater than the period threshold, taking the compensated value of the maintenance duration as the corrected valve adjustment period. If the compensated maintenance duration 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 amplitude at the current actual superheat degree specifically includes: obtaining the target superheat degree, the current actual superheat degree, and the previous actual superheat degree; calculating the current opening degree, and the calculation formula for the current opening degree is: Un = Un-1 + Kp * (En - En-1) + (Tac ÷ Ti) * En; En = Qn - Q; calculating the valve adjustment amplitude, and the calculation formula for the valve adjustment amplitude is: P = Un - Un-1; where Un is the opening degree of the current electronic expansion valve, Un-1 is the opening degree of the previous electronic expansion valve, En is the difference between the current actual superheat degree and the target superheat degree, En-1 is the difference between the previous actual superheat degree and the target superheat degree, Kp is the proportional gain coefficient, Tac is the numerator of the difference ratio coefficient, Ti is the denominator of the difference ratio coefficient, Qn is the current actual superheat degree, Q is the target superheat degree, and P is the valve adjustment amplitude.

[0007] In a possible implementation, the step of adjusting the valve according to the corrected valve adjustment period and the valve adjustment amplitude specifically includes: in response to the maintenance duration of the actual superheat degree reaching a multiple of the corrected valve adjustment period, compensating the opening degree of the electronic expansion valve by the valve adjustment amplitude; the step of adjusting the valve according to the valve adjustment period and the valve adjustment amplitude specifically includes: In response to the maintenance duration 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.

[0008] In a possible implementation, the step of adjusting the valve further includes: judging whether the valve adjustment amplitude exceeds the valve adjustment threshold; if the valve adjustment amplitude does not exceed the valve adjustment threshold, adjusting the valve according to the valve adjustment amplitude, and if the valve adjustment amplitude exceeds the valve adjustment threshold, adjusting the valve according to the valve adjustment threshold.

[0009] In a possible implementation, the step of determining the valve adjustment period based on the magnitude of the current actual superheat degree specifically includes: calculating the absolute value of the difference between the current actual superheat degree and the target superheat degree, where the magnitude of the valve adjustment period is inversely proportional to the absolute value.

[0010] To solve the above technical problems, another technical solution adopted in this application is to provide a controller. The controller controls the opening degree of the electronic expansion valve through the above control method. The controller includes: a calculation module for obtaining the valve adjustment amplitude at the current actual superheat degree; a judgment module for judging whether the previous actual superheat degree is not less than the target superheat degree; a control module, if the previous actual superheat degree is not less than the target superheat degree and the maintenance duration of the previous actual superheat degree reaches the threshold duration, correcting the maintenance duration to obtain a corrected valve adjustment period, and performing valve adjustment according to the corrected valve adjustment period and the valve adjustment amplitude; if the previous actual superheat degree is less than the target superheat degree, or the maintenance duration of the previous actual superheat degree does not reach the threshold duration, determining the valve adjustment period based on the magnitude of the current actual superheat degree, and performing valve adjustment 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 unit, the step of obtaining the valve adjustment amplitude at the current actual superheat degree is executed again.

[0011] To solve the above technical problems, another technical solution adopted in this application is to provide a heat pump unit, and the opening degree of the electronic expansion valve of the heat pump unit is controlled by the above control method.

[0012] To solve the above technical problems, another technical solution adopted in this application is to provide an electronic device, which includes: a processor; a memory connected to the processor for storing a computer program that can run on the processor; wherein, when the processor executes the computer program, the above control method is implemented.

[0013] To solve the above technical problems, another technical solution adopted in this application is to provide a computer-readable storage medium, and when the computer program stored therein is executed by a processor, the above control method is implemented.

[0014] The beneficial effect of this application is that, different from the prior art, this application provides a control method for the electronic expansion valve of a heat pump unit. When the actual superheat degree of the heat pump unit reaches the target superheat degree, that is, when the heat pump unit starts to be stable or overshoots, the maintenance duration 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. This control scheme for dynamically correcting the valve adjustment period can reduce the valve adjustment frequency according to the stability of the actual superheat degree when the heat pump unit starts to be stable or the electronic expansion valve overshoots. The closer the actual superheat degree is to the target superheat degree, the longer the maintenance duration is, and the larger the corrected valve adjustment period is, which can reduce the problems of overshoot and unstable heating, and thus can improve the problem that the actual superheat degree of the heat pump unit fluctuates frequently near the target superheat degree. Description of the Drawings

[0015] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0016] Figure 1 is a schematic structural diagram of an embodiment of a heat pump provided by the present application; Figure 2 is a schematic flowchart of an embodiment of a control method for an electronic expansion valve of a heat pump of the present application; Figure 3 is Figure 2 a schematic flowchart of an embodiment of S11 in Figure 4 is a schematic block diagram of an embodiment of a controller of the present application; Figure 5 is a schematic block diagram of an embodiment of an electronic device of the present application; Figure 6 is a schematic block diagram of an embodiment of a computer-readable storage medium of the present application. Specific Embodiments

[0017] The following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present application.

[0018] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "the" and "said" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless clearly indicated otherwise in the foregoing. "Multiple" generally includes at least two, but does not exclude the case of including at least one.

[0019] It should be understood that the term " / and / " used herein is only a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0020] It should be understood that the term "including", "comprising" or any other variant used herein is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including..." does not exclude the presence of additional identical elements in the process, method, article or device including the said element.

[0021] In the related art, there are problems of over-opening or over-closing in the opening control of the electronic expansion valve. Especially when the ambient temperature is relatively low, the opening of the electronic expansion valve is small, and the actual superheat of the heat pump is close to the target superheat, it is easy to have a significant lag in the change of the valve adjustment reflected in the real-time superheat, resulting in frequent fluctuations of the actual superheat of the heat pump near the target superheat, and the heat exchange effect of the heat pump is poor.

[0022] Based on the above problems, the present application proposes a control method, a controller, a heat pump, related equipment and a medium for the electronic expansion valve of a heat pump. It can dynamically adjust the valve adjustment period according to the change of the actual superheat, reduce the problems of over-opening and over-closing of the electronic expansion valve, and improve the heat exchange effect of the heat pump.

[0023] The following describes in detail a control method, a controller, a heat pump, related equipment and a medium for the electronic expansion valve of a heat pump provided by the present application in conjunction with the drawings and embodiments.

[0024] The present application provides a control method for the electronic expansion valve of a heat pump, which is used to adjust the opening of the electronic expansion valve of the heat pump so that the real-time superheat of the heat pump is an appropriate value, enabling the heat pump to have a high heat exchange efficiency with the environment and improving the heat exchange effect of the heat pump. Please refer to Figure 1 , Figure 1 which is a schematic structural diagram of an embodiment of the heat pump provided by the present application. In a specific embodiment, the heat pump (not labeled) includes a four-way valve 11, a compressor 12, an electronic expansion valve 15, an evaporator 13 located outdoors, and a condenser 14 located indoors.

[0025] Among them, the compressor 12 is used to compress the low-temperature and low-pressure gaseous refrigerant to transform it into a high-temperature and high-pressure gaseous refrigerant. The four-way valve 11 is used to switch states and change the flow direction of the refrigerant, playing a role in switching the cooling and heating modes in the heat pump. When the refrigerant cycle is in the cooling 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 connection state, so that the refrigerant first flows through the condenser 14 and then flows to the evaporator 13.

[0026] The electronic expansion valve 15 is used to adjust the flow rate of the refrigerant in the circulation path of the heat pump unit, so that in different environments, by adjusting the electronic expansion valve 15, the heat pump unit can be maintained at a reasonable real-time superheat degree, which can increase the heat exchange amount and improve the heat exchange efficiency. Among them, when the real-time superheat degree is too high, the opening degree of the electronic expansion valve 15 can be increased to increase the refrigerant flow rate, thereby reducing the suction gas temperature of the compressor 12, reducing the real-time superheat degree, and reducing the problem of compressor 12 overheating. When the real-time superheat degree is too low, the opening degree of the electronic expansion valve 15 can be reduced to reduce the refrigerant flow rate, thereby improving the energy efficiency and reducing energy waste.

[0027] In some embodiments, the heat pump unit in the embodiments of the present application further includes a controller (not labeled), and the controller is connected to the compressor 12, the four-way valve 11, the electronic expansion valve 15, etc. of the heat pump unit. The execution subject of the control method of the electronic expansion valve 15 of the heat pump unit in this embodiment is the controller.

[0028] To improve the problem of over-opening or over-closing in the opening control of the electronic expansion valve, especially when the environmental temperature is low, the opening degree of the electronic expansion valve is small, and the actual superheat degree of the heat pump unit is close to the target superheat degree, it is easy to have a significant lag in the change of the valve adjustment reflected in the real-time superheat degree, resulting in frequent fluctuations of the actual superheat degree of the heat pump unit near the target superheat degree and poor heat exchange effect of the heat pump unit. The present application proposes a control method, a controller, a heat pump unit, related devices and media for the electronic expansion valve of the heat pump unit to solve the above technical problems.

[0029] Please refer to Figure 2 , Figure 2 which is a schematic flowchart of an embodiment of the control method for the electronic expansion valve of the heat pump unit of the present application. This method is used to adjust the opening degree of the electronic expansion valve. In a specific embodiment, this method includes: S11: Obtain the valve adjustment amplitude at the current actual superheat degree; determine whether the previous actual superheat degree is not less than the target superheat degree.

[0030] In S11, first execute the step of obtaining the valve adjustment amplitude at the current actual superheat degree, and then execute the step of determining whether the previous actual superheat degree is not less than the target superheat degree.

[0031] If the previous actual superheat degree is not less than the target superheat degree, then execute S12; otherwise, execute S14.

[0032] This step is executed when the real superheat of the heat pump changes. Among them, 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 is less than the target superheat, the valve adjustment amplitude is negative; when the actual superheat is greater than the target superheat, the valve adjustment amplitude is positive. So that adjusting the valve through the valve adjustment amplitude can make the actual superheat approach the target superheat. In some embodiments, the magnitude of the absolute value of the valve adjustment amplitude is positively correlated with the magnitude of the absolute value of the difference between the actual superheat and the target superheat.

[0033] In some embodiments, the steps of calculating the valve adjustment amplitude may specifically include: obtaining the target superheat, the current actual superheat, and the previous actual superheat; calculating the current opening, and the calculation formula for the current opening is: Un = Un-1 + Kp * (En - En-1) + (Tac ÷ Ti) * En; En = Qn - Q; calculating the valve adjustment amplitude, and the calculation formula for the valve adjustment amplitude is: P = Un - Un-1; where Un is the current opening of the electronic expansion valve, Un-1 is the previous opening of the electronic expansion valve, En is the difference between the current actual superheat and the target superheat, En-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 ratio coefficient, Ti is the denominator of the difference ratio coefficient, Qn is the current actual superheat, Q is the target superheat, and P is the valve adjustment amplitude.

[0034] S12: Determine whether the maintenance duration of the previous actual superheat reaches the threshold duration.

[0035] Among them, if the maintenance duration of the previous actual superheat reaches the threshold duration, then execute S131; if the maintenance duration of the previous actual superheat does not reach the threshold duration, then execute S132.

[0036] In this embodiment, to reduce the problem of compressor overheating when the heat pump starts, when the device starts, the electronic expansion valve is at a relatively large opening value, which can reduce the problem of compressor overheating and avoid equipment failure. During the operation of the heat pump, the valve is adjusted according to the change of the actual superheat, and the opening of the electronic expansion valve is gradually reduced, so that the actual superheat of the heat pump gradually increases, and the actual superheat gradually approaches the target superheat, improving the heating effect. Among them, when the previous actual superheat is not less than the target superheat and the maintenance duration can reach the threshold duration, it reflects that the heat pump has started to stabilize or the electronic expansion valve has started to overshoot.

[0037] S132: Determine the valve adjustment period based on the magnitude of the current actual superheat, and adjust the valve according to the valve adjustment period and the valve adjustment amplitude.

[0038] The size of the valve adjustment period is related to the size of the actual superheat. The steps to determine the valve adjustment period based on the size of the actual superheat this time may include: calculating the absolute value of the difference between the actual superheat this time and the target superheat. Among them, 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 and the target superheat, the farther the heat pump is from the target superheat, which makes the valve adjustment period smaller, can improve the valve adjustment frequency of the electronic expansion valve, and can perform higher-frequency valve adjustments when the heat pump is farther from the target superheat, so that the heat pump can approach the target superheat more quickly. The smaller the absolute value of the difference between the actual superheat and the target superheat, the closer the heat pump is to the target superheat, which makes the valve adjustment period larger, can reduce the valve adjustment frequency of the electronic expansion valve, can perform lower-frequency valve adjustments when the heat pump is closer to the target superheat, can reduce the problem of over-adjustment, and can make the real-time superheat of the heat pump stable near the real-time superheat and reduce frequent fluctuations.

[0039] For example, in a specific application scenario, the relationship between the size of the valve adjustment period and the size of the actual superheat can be as follows: when the difference between the actual superheat and the target superheat is not less than 3 degrees Celsius, the valve adjustment 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 adjustment 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 adjustment 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 adjustment period is the fourth value; when the difference between the actual superheat and the target superheat is less than -2 degrees Celsius, the valve adjustment period is the fifth value. Among them, 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.

[0040] In some embodiments, the steps of adjusting the valve according to the valve adjustment period and the valve adjustment amplitude specifically include: in response to the maintenance duration of the actual superheat reaching a multiple of the valve adjustment period, compensating the opening of the electronic expansion valve by the valve adjustment amplitude. Specifically, for example: if the valve adjustment amplitude is 1 and the valve adjustment period is 20 seconds, the maintenance duration of the heat pump at the current actual superheat is statistically calculated in real time. Among them, when the maintenance duration reaches 20 seconds, the opening of the electronic expansion valve is increased by 1, and when the maintenance duration reaches 40 seconds, the opening of the electronic expansion valve is increased by 1 again until the real-time superheat of the heat pump changes.

[0041] S1321: In response to the change in the actual superheat of the heat pump, the step of obtaining the valve adjustment amplitude at the current actual superheat is executed again.

[0042] S131: Correct the duration of maintenance to obtain a corrected valve adjustment period, and perform valve adjustment according to the corrected valve adjustment period and the valve adjustment amplitude.

[0043] Among them, the threshold duration is a preset duration. Preferably, the threshold duration is greater than the valve adjustment period. When the previous actual superheat degree is not less than the target superheat degree and the maintenance duration reaches the threshold duration, it indicates that the heat pump has started to stabilize or the electronic expansion valve has started to overshoot. If the valve adjustment continues based on the above valve adjustment period, it is easy to have problems such as overshoot and large fluctuations in the real-time superheat degree. Therefore, this step is executed when the previous actual superheat degree is not less than the target superheat degree and the maintenance duration of the previous actual superheat degree reaches the threshold duration. In this step, the corrected valve adjustment period obtained by correcting the maintenance duration is greater than the above valve adjustment period, which can reduce the valve adjustment frequency when the heat pump starts to stabilize or the electronic expansion valve overshoots, reduce overshoot and unstable heating problems, and thus improve the problem that the actual superheat degree of the heat pump fluctuates frequently near the target superheat degree. On the other hand, in this step, it is to correct the maintenance duration to obtain the corrected valve adjustment period. The size of the corrected valve adjustment period is related to the maintenance duration of the previous actual superheat degree. The greater the maintenance duration of the previous actual superheat degree, the greater the corrected valve adjustment period; the smaller the maintenance duration, the smaller the corrected valve adjustment period. It is easy to understand that the greater the maintenance duration of the previous actual superheat degree, the smaller the overshoot or overshoot problem of the heat pump, and the closer the electronic expansion valve is to the ideal opening degree. Therefore, by using a larger corrected valve adjustment period for valve adjustment, the problem of overshoot can be reduced and the heating of the heat pump can be stabilized. The smaller the maintenance duration of the previous actual superheat degree, the greater the overshoot problem of the heat pump. Therefore, by using a smaller corrected valve adjustment period for valve adjustment, the electronic expansion valve can approach the ideal opening degree more quickly and the heating of the heat pump can be stabilized. In a specific embodiment, the threshold duration can be 30 seconds. In some other embodiments, the threshold duration can also be 35 seconds, 40 seconds or other reasonable values.

[0044] In some embodiments, the step of correcting the maintenance duration to obtain the corrected valve adjustment period specifically includes: compensating the maintenance duration by a fixed duration to obtain the corrected valve adjustment period. For example, in a specific application scenario, the fixed duration is set to 10 seconds. If the maintenance duration of the previous actual superheat degree is 50 seconds, the corrected valve adjustment period is 60 seconds; if the maintenance duration of the previous actual superheat degree is 60 seconds, the corrected valve adjustment period is 70 seconds. Further, in some preferred embodiments, the step of correcting the maintenance duration to obtain the corrected valve adjustment period further includes: determining whether the compensated maintenance duration is greater than the period threshold. If the compensated maintenance duration is not greater than the period threshold, the value after compensating the maintenance duration is used as the corrected valve adjustment period. If the compensated maintenance duration is greater than the period threshold, the period threshold is used as the corrected valve adjustment 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 or other reasonable values.

[0045] In some embodiments, the step of adjusting the valve according to the corrected valve adjustment period and the valve adjustment amplitude specifically includes: in response to the maintenance duration of the actual superheat degree reaching a multiple of the corrected valve adjustment period, compensating the opening of the electronic expansion valve by the valve adjustment amplitude. Specifically, by way of example: if the valve adjustment amplitude is 1 and the corrected valve adjustment period is 60 seconds, the maintenance duration of the heat pump at the current actual superheat degree is statistically calculated in real time. Among them, when the maintenance duration reaches 60 seconds, the opening of the electronic expansion valve is increased by 1, and when the maintenance duration reaches 120 seconds, the opening of the electronic expansion valve is increased by 1 again until the real-time superheat degree of the heat pump changes.

[0046] S1311: In response to the change in the actual superheat degree of the heat pump, the step of obtaining the valve adjustment amplitude at the current actual superheat degree is executed again.

[0047] Further, in some embodiments, the step of adjusting the valve further includes: determining whether the valve adjustment amplitude exceeds the valve adjustment threshold; if the valve adjustment amplitude does not exceed the valve adjustment threshold, adjusting the valve according to the valve adjustment amplitude, and if the valve adjustment amplitude exceeds the valve adjustment threshold, adjusting the valve according to the valve adjustment threshold. For example, in a specific application scenario, the value range of the valve adjustment amplitude is set to -1 to 1. When the calculated valve adjustment amplitude is -2, the valve is adjusted with the valve adjustment threshold -1. When the calculated valve adjustment amplitude is 1, the valve is adjusted with the valve adjustment amplitude 1. When the calculated valve adjustment amplitude is 3, the valve is adjusted with the valve adjustment threshold 1. The above can reduce the problem that the valve adjustment amplitude is too large and the electronic expansion valve is prone to over-adjustment. In some other embodiments, the value range of the valve adjustment amplitude can also be a reasonable range such as -1 to 2, -2 to 2, etc.

[0048] S14: Determine the valve adjustment period based on the magnitude of the current actual superheat degree, and adjust the valve according to the valve adjustment period and the valve adjustment amplitude.

[0049] S15: In response to the change in the actual superheat degree of the heat pump, the step of obtaining the valve adjustment amplitude at the current actual superheat degree is executed again.

[0050] After executing S14, execute S15.

[0051] Please refer to Figure 3 , Figure 3 is Figure 2 a schematic flowchart of an implementation manner of S11 in S21: Determine whether the previous actual superheat degree is not less than the target superheat degree.

[0052] If the previous actual superheat degree is not less than the target superheat degree, then execute S12; if the previous actual superheat degree is less than the target superheat degree, then execute S22.

[0053] S12: In response to the previous actual superheat degree being not less than the target superheat degree, determine whether the duration of maintaining the previous actual superheat degree reaches the threshold duration.

[0054] Please refer to the above S12 and will not be elaborated here.

[0055] S22: Determine the valve adjustment period based on the magnitude of the current actual superheat degree, and perform valve adjustment according to the valve adjustment period and the valve adjustment amplitude.

[0056] The magnitude of the valve adjustment period is related to the magnitude of the actual superheat degree. The steps of determining the valve adjustment period based on the magnitude of the current actual superheat degree may include: calculating the absolute value of the difference between the current actual superheat degree and the target superheat degree, where the magnitude 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 unit 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 unit is farther from the target superheat degree, so that the heat pump unit 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 unit is to the target superheat degree, which makes the valve adjustment period larger, can reduce the valve adjustment frequency of the electronic expansion valve, can perform lower-frequency valve adjustment when the heat pump unit is closer to the target superheat degree, can reduce the problem of overshoot, and can make the real-time superheat degree of the heat pump unit stable near the real-time superheat degree and reduce frequent fluctuations.

[0057] Different from the prior art, the present application provides a control method for an electronic expansion valve of a heat pump unit. When the actual superheat degree of the heat pump unit reaches the target superheat degree, that is, when the heat pump unit starts to be stable or overshoot occurs, the control method obtains a corrected valve adjustment period by correcting the duration of maintaining the real-time superheat degree, and controls the valve adjustment according to the corrected valve adjustment period. This control scheme for dynamically correcting the valve adjustment period can reduce the valve adjustment frequency according to the stability of the actual superheat degree when the heat pump unit starts to be stable or the electronic expansion valve overshoots. The closer the actual superheat degree is to the target superheat degree, the larger the duration of maintenance, and the larger the corrected valve adjustment period, which can reduce the problems of overshoot and unstable heating, thereby improving the problem that the actual superheat degree of the heat pump unit fluctuates frequently near the target superheat degree.

[0058] Finally, in a specific application scenario, please refer to Table 1 in combination: Table 1

[0059] As described above, Table 1 shows the parameter changes of the heat pump in a specific control process. Among them, in this application scenario, the range of the valve adjustment threshold is -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 adjustment 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 adjustment 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 adjustment 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 degree Celsius, the valve adjustment period is the fourth value; when the difference between the actual superheat and the target superheat is less than -2 degrees Celsius, the valve adjustment period is the fifth value. Among them, 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.

[0060] As shown in the first column of the above table, if the real-time superheat is less than the target superheat, the valve adjustment period is determined based on the magnitude of the current actual superheat, and the valve is adjusted according to the valve adjustment period and the valve adjustment amplitude. It is calculated that the valve adjustment amplitude is -1, and the difference between the real-time superheat and the target superheat is -3, so the valve adjustment period is 20 seconds. The actual superheat maintenance duration is 40 seconds, so 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, in the second to fourth columns, the maintenance duration of the actual superheat is less than the valve adjustment period, and no valve adjustment is performed. As shown in the fifth column, the actual superheat is greater than the target superheat, but the maintenance duration of the previous actual superheat does not reach the threshold duration, so the valve adjustment period is still determined based on the magnitude of the current actual superheat, and the valve is adjusted according to the valve adjustment period and the valve adjustment amplitude. It is calculated that the valve adjustment period is 25 seconds, the valve adjustment amplitude is 1, and the maintenance duration reaches twice the valve adjustment period, so 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 previous actual superheat reaches the threshold duration, so the maintenance duration of the previous actual superheat is corrected in this column to obtain the corrected valve adjustment period, and the valve is adjusted according to the corrected valve adjustment period and the valve adjustment amplitude. It is calculated that the valve adjustment amplitude is -1, and the corrected valve adjustment period is calculated to be 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 and will not be elaborated here.

[0061] In the above control method, when the actual superheat of the heat pump reaches the target superheat, that is, when the heat pump starts to stabilize or overshoot occurs, the maintenance duration of the real-time superheat is corrected to obtain a corrected valve adjustment period, and the valve is controlled according to the corrected valve adjustment period. This control scheme for dynamically correcting the valve adjustment period can reduce the valve adjustment frequency according to the stability of the actual superheat when the heat pump starts to stabilize or the electronic expansion valve overshoots. The closer the actual superheat is to the target superheat, the greater the maintenance duration, and the greater the corrected valve adjustment period, which can reduce overshoot and unstable heating problems, thereby improving the problem that the actual superheat of the heat pump fluctuates frequently near the target superheat.

[0062] Correspondingly, the present application also proposes a heat pump, and the opening degree of the electronic expansion valve of the heat pump is controlled by the control method described in the above embodiment.

[0063] Please refer to Figure 4 , Figure 4 FIG. is a structural block diagram of an embodiment of the controller of the present application. Correspondingly, the present application also proposes a controller 1000, and the opening degree of the electronic expansion valve of the controller 1000 is controlled by the above control method. The controller 1000 includes a calculation module 3000, a control module 2000, and a judgment module 4000. The calculation module 3000 is used to obtain the valve adjustment amplitude at the current actual superheat; the judgment module 4000 is used to judge whether the previous actual superheat is not less than the target superheat; the control module 2000, if the previous actual superheat is not less than the target superheat and the maintenance duration of the previous actual superheat reaches the threshold duration, corrects the maintenance duration to obtain a corrected valve adjustment period, and performs valve adjustment according to the corrected valve adjustment period and the valve adjustment amplitude; if the previous actual superheat is less than the target superheat, or the maintenance duration of the previous actual superheat does not reach the threshold duration, determines the valve adjustment period based on the size of the current actual superheat, and performs valve adjustment according to the valve adjustment period and the valve adjustment 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 executed again.

[0064] In some embodiments, the step of correcting the maintenance duration to obtain a corrected valve adjustment period specifically includes: compensating the maintenance duration by a fixed duration to obtain the corrected valve adjustment period; wherein, the step of correcting the maintenance duration to obtain a corrected valve adjustment period further includes: judging whether the compensated maintenance duration is greater than the period threshold, if the compensated maintenance duration is not greater than the period threshold, taking the compensated value of the maintenance duration as the corrected valve adjustment period, and if the compensated maintenance duration is greater than the period threshold, taking the period threshold as the corrected valve adjustment period.

[0065] In some embodiments, the step of obtaining the valve adjustment amplitude at the current actual superheat degree specifically includes: obtaining the target superheat degree, the current actual superheat degree, and the previous actual superheat degree; calculating the current opening degree, and the calculation formula for the current opening degree is: Un = Un-1 + Kp * (En - En-1) + (Tac ÷ Ti) * En; En = Qn - Q; calculating the valve adjustment amplitude, and the calculation formula for the valve adjustment amplitude is: P = Un - Un-1; where Un is the opening degree of the current electronic expansion valve, Un-1 is the opening degree of the previous electronic expansion valve, En is the difference between the current actual superheat degree and the target superheat degree, En-1 is the difference between the previous actual superheat degree and the target superheat degree, Kp is the proportional gain coefficient, Tac is the numerator of the difference ratio coefficient, Ti is the denominator of the difference ratio coefficient, Qn is the current actual superheat degree, Q is the target superheat degree, and P is the valve adjustment amplitude.

[0066] In some embodiments, the step of adjusting the valve according to the corrected valve adjustment period and the valve adjustment amplitude specifically includes: in response to the maintenance duration of the actual superheat degree reaching a multiple of the corrected valve adjustment period, compensating the opening degree of the electronic expansion valve by the valve adjustment amplitude; the step of adjusting the valve according to the valve adjustment period and the valve adjustment amplitude specifically includes: in response to the maintenance duration 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.

[0067] In some embodiments, the step of adjusting the valve further includes: determining whether the valve adjustment amplitude exceeds the valve adjustment threshold; if the valve adjustment amplitude does not exceed the valve adjustment threshold, adjusting the valve according to the valve adjustment amplitude, and if the valve adjustment amplitude exceeds the valve adjustment threshold, adjusting the valve according to the valve adjustment threshold.

[0068] In some embodiments, the step of determining the valve adjustment period based on the magnitude of the current actual superheat degree specifically includes: calculating the absolute value of the difference between the current actual superheat degree and the target superheat degree, where the magnitude of the valve adjustment period is inversely proportional to the absolute value.

[0069] Correspondingly, the present application further provides an electronic device. Please refer to Figure 5 , Figure 5 which is a structural schematic diagram of an embodiment of the electronic device of the present application. The electronic device 200 includes a processor 220 and a memory 210. The memory 210 is connected to the processor 220 and is used to store a computer program that can run on the processor 220; wherein, when the processor 220 executes the computer program, it implements the control method of any one of the above embodiments. The present application further provides a computer-readable storage medium. Please refer to Figure 6 , Figure 6It is 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 a computer program 300 thereon. When the computer program 300 is executed by a processor, it implements the control method of any of the above embodiments.

[0070] Specifically, the computer-readable storage medium 30 can be a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disc, etc., which can store the computer program 300, or it can also be a server storing the computer program 300. The server can send the stored computer program 300 to other devices for running, or it can also run the stored computer program 300 by itself.

[0071] In several embodiments provided by the present application, it should be understood that the disclosed methods, devices, and apparatuses can be implemented in other ways. For example, the device and apparatus embodiments described above are only illustrative. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed mutual coupling, direct coupling, or communication connection can be through some interfaces. The indirect coupling or communication connection of devices or units can be in an electrical, mechanical, or other form.

[0072] The units described as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place, or they can be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0073] In addition, in each embodiment of the present application, each functional unit can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above integrated units can be implemented in the form of hardware or in the form of software functional units.

[0074] When the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to execute all or part of the steps of the methods in various embodiments of this application. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs 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: Obtaining the valve adjustment amplitude at the current actual superheat degree; Judging whether the previous actual superheat degree is not less than the target superheat degree; If the previous actual superheat degree is not less than the target superheat degree and the maintaining duration of the previous actual superheat degree reaches the threshold duration, correcting the maintaining duration to obtain a corrected valve adjustment period, and performing valve adjustment according to the corrected valve adjustment period and the valve adjustment amplitude; If the previous actual superheat degree is less than the target superheat degree, or the maintaining duration of the previous actual superheat degree does not reach the threshold duration, determining the valve adjustment period based on the magnitude of the current actual superheat degree, and performing valve adjustment according to the valve adjustment period and the valve adjustment amplitude; In response to a change in the actual superheat degree of the heat pump unit, the step of obtaining the valve adjustment amplitude at the current actual superheat degree is executed again.

2. The control method according to claim 1, wherein The step of correcting the maintaining duration to obtain a corrected valve adjustment period specifically includes: Compensating the maintaining duration by a fixed duration to obtain the corrected valve adjustment period; Wherein, the step of correcting the maintaining duration to obtain a corrected valve adjustment period further includes: Judging whether the compensated maintaining duration is greater than the period threshold. If the compensated maintaining duration is not greater than the period threshold, taking the compensated value of the maintaining duration as the corrected valve adjustment period. If the compensated maintaining duration is greater than the period threshold, taking the period threshold as the corrected valve adjustment period.

3. The control method according to claim 1, wherein The step of obtaining the valve adjustment amplitude at the current actual superheat degree specifically includes: Obtaining the target superheat degree, the current actual superheat degree, and the previous actual superheat degree; Calculating the current opening degree, and the calculation formula of the current opening degree is: U n = U n-1 + Kp * (E n - E n-1 ) + (Tac ÷ Ti) * E n ; E n =Q n -Q; Calculate the regulating valve amplitude, and the calculation formula of the regulating valve amplitude is: P = U n - U n-1 ; Among them, U n is the opening degree of the electronic expansion valve this time, U n-1 is the opening degree of the electronic expansion valve last time, E n is the difference between the actual superheat degree and the target superheat degree this time, E n-1 is the difference between the actual superheat degree and the target superheat degree last time, Kp is the proportional gain coefficient, Tac is the numerator of the difference ratio coefficient, Ti is the denominator of the difference ratio coefficient, Q n is the actual superheat degree this time, Q is the target superheat degree, and P is the valve adjustment amplitude.

4. According to the control method described in claim 1, wherein The step of performing valve adjustment according to the corrected valve adjustment period and the valve adjustment amplitude specifically includes: In response to the maintaining duration of the actual superheat degree reaching a multiple of the corrected valve adjustment period, compensating the opening degree of the electronic expansion valve by the valve adjustment amplitude; The step of performing valve adjustment according to the valve adjustment period and the valve adjustment amplitude specifically includes: In response to the maintaining duration 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.

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

6. The control method according to claim 1, wherein The step of determining the valve adjustment period based on the magnitude of the current actual superheat degree specifically includes: Calculating the absolute value of the difference between the current actual superheat degree and the target superheat degree, wherein the magnitude of the valve adjustment period is inversely proportional to the absolute value.

7. A controller, characterized in that, The controller controls the opening degree of the electronic expansion valve by the control method described in any one of claims 1-6. The controller includes: A calculation module, which is used to obtain the valve adjustment amplitude at the current actual superheat degree; A judgment module, which is used to judge whether the previous actual superheat degree is not less than the target superheat degree; The control module, if the previous actual superheat degree is not less than the target superheat degree and the maintenance duration of the previous actual superheat degree reaches the threshold duration, corrects the maintenance duration to obtain a corrected valve adjustment period, and performs valve adjustment according to the corrected valve adjustment period and the valve adjustment amplitude; if the previous actual superheat degree is less than the target superheat degree or the maintenance duration of the previous actual superheat degree does not reach the threshold duration, determines the valve adjustment period based on the magnitude of the current actual superheat degree, and performs valve adjustment according to the valve adjustment period and the valve adjustment amplitude; in response to the change in the actual superheat degree of the heat pump unit, the step of obtaining the valve adjustment amplitude at the current actual superheat degree is executed again.

8. A heat pump, characterized in that, The heat pump unit controls the opening degree of the electronic expansion valve by the control method according to any one of claims 1-6.

9. An electronic device, characterized in that, Comprising: A processor; A memory connected to the processor for storing a computer program that can run on the processor; wherein, when the processor executes the computer program, the control method according to any one of claims 1 to 6 is implemented.

10. A computer-readable storage medium, characterized in that, A computer program is stored on the computer-readable storage medium, and when the computer program is executed by the processor, the control method according to any one of claims 1 to 6 is implemented.

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