Expansion valve control method and system considering the constitutive configuration of an air source heat pump

Abstract

The expansion valve control method and system considering the constitutive configuration of an air source heat pump disclosed by the present invention include: obtaining the ambient temperature, the inlet water temperature, the outlet water temperature and the mass flow rate of water on the condensing side, as well as the compressor frequency, the exhaust temperature and the exhaust pressure; calculating and determining the theoretical evaporation temperature, the theoretical condensation temperature and the actual exhaust superheat degree according to the obtained various data and the air source heat pump constitutive configuration parameters; calculating the temperature deviation between the compressor exhaust temperature and the exhaust alarm limit temperature; when the temperature deviation is greater than or equal to the set temperature deviation threshold, calculating and determining the target exhaust superheat degree according to the compressor frequency, the theoretical evaporation temperature, the theoretical condensation temperature and the target exhaust superheat degree calculation model; and performing exhaust superheat degree control on the expansion valve according to the target exhaust superheat degree and the actual exhaust superheat degree. The precise control of the expansion valve of the air source heat pump is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of expansion valve control of air source heat pumps, and particularly to an expansion valve control method and system considering the constitutive configuration of air source heat pumps. Background Art

[0002] The statements in this section merely provide background technical information related to the present invention and do not necessarily constitute prior art.

[0003] In recent years, as an efficient and energy-saving clean energy technology, air source heat pumps have received unprecedented attention in the building field. Compared with traditional heating methods such as coal combustion, air source heat pumps have significant energy-saving and environmental protection advantages and have become a key technology for achieving clean heating and the dual-carbon goal.

[0004] In an air source heat pump system, the electronic expansion valve is a key component, and its precise control directly affects the energy efficiency and stability of the system, which is a key factor to ensure the safe and efficient operation of the air source heat pump. Traditional electronic expansion valve control strategies usually take the suction superheat of the compressor as the control target. However, at low ambient temperatures, the suction superheat is small, the requirement for the measurement point accuracy is high, and the control difficulty increases, which easily leads to oscillation phenomena in the system, resulting in large errors in the control process and thus reducing the energy efficiency of the unit operation.

[0005] In contrast, controlling the opening of the expansion valve through the discharge superheat has low requirements for the measurement point accuracy and can effectively solve the system oscillation problem during the suction superheat control. However, the compressor discharge superheat is not only related to the compressor frequency, ambient temperature, and water supply temperature, but also restricted by the constitutive configuration parameters of the air source heat pump, including the evaporator heat transfer area, compressor stroke volume, fan air volume, condenser heat transfer coefficient, condensing side heat transfer area, etc. The constitutive configuration parameters affect the discharge superheat by influencing the evaporation and condensation temperatures. However, in related technologies, the influence of the constitutive configuration parameters of the air source heat pump is not considered during the discharge superheat control of the expansion valve, resulting in low control accuracy of the expansion valve. Summary of the Invention

[0006] To solve the above problems, the present invention proposes an expansion valve control method and system considering the constitutive configuration of an air source heat pump, establishes a discharge superheat target calculation model considering the constitutive configuration parameters of the air source heat pump, and considers the constitutive configuration parameters of the air source heat pump when controlling the expansion valve, thereby improving the control accuracy of the expansion valve.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] In the first aspect, an expansion valve control method considering the constitutive configuration of an air source heat pump is proposed, including:

[0009] Obtain the ambient temperature, the inlet temperature, the outlet temperature of the condensing side, the mass flow rate of water, as well as the compressor frequency, the exhaust temperature and the exhaust pressure;

[0010] According to the obtained data and the constitutive configuration parameters of the air source heat pump, calculate the theoretical evaporation temperature and the theoretical condensation temperature according to the theoretical evaporation temperature model and the theoretical condensation temperature model;

[0011] Calculate the actual condensation temperature according to the compressor exhaust pressure and the refrigerant physical property parameters, and calculate the actual exhaust superheat degree according to the actual condensation temperature;

[0012] Calculate the temperature deviation between the compressor exhaust temperature and the exhaust alarm limit temperature;

[0013] When the temperature deviation is greater than or equal to the set temperature deviation threshold, calculate and determine the target exhaust superheat degree according to the compressor frequency, the theoretical evaporation temperature and the theoretical condensation temperature according to the target exhaust superheat degree calculation model; among them, the target exhaust superheat degree calculation model is fitted from the compressor sample data, and the compressor sample data includes the existing theoretical evaporation temperature, compressor frequency, theoretical condensation temperature and the corresponding target exhaust superheat degree;

[0014] Control the exhaust superheat degree of the expansion valve according to the target exhaust superheat degree and the actual exhaust superheat degree.

[0015] Furthermore, the process of controlling the exhaust superheat degree of the expansion valve according to the target exhaust superheat degree and the actual exhaust superheat degree includes:

[0016] Calculate the superheat degree error between the actual exhaust superheat degree and the target exhaust superheat degree;

[0017] When the superheat degree error is greater than the set superheat degree error threshold, perform PID control on the expansion valve according to the target exhaust superheat degree; when the superheat degree error is less than or equal to the set superheat degree error threshold, the system continues to run stably.

[0018] Furthermore, when the temperature deviation is less than the set temperature deviation threshold, perform PID control on the expansion valve according to the target exhaust temperature.

[0019] Furthermore, the target exhaust superheat degree calculation model is:

[0020] T set_dsh =

[0021] (18.228 - 0.081829n — 0.0049469T e + 0.090717T c + 0.0013215n 2 + 0.029106

[0022] Te 2 +0.0085057 T c 2 +0.0013556 nT e -0.0028757 nT c -0.027437 T e T c ) × γ _1

[0023] Wherein, T set_dsh is the target exhaust superheat, T e is the theoretical evaporation temperature, T c is the theoretical condensation temperature, n is the compressor frequency, γ _1 is the correction factor.

[0024] Furthermore, the theoretical evaporation temperature model is:

[0025]

[0026] Wherein, T a is the ambient temperature, n is the compressor frequency, G is the rated air volume of the outdoor fan, F e is the outdoor heat exchange area on the evaporation side, V o is the stroke volume of the compressor, T e is the theoretical evaporation temperature, α is the correction factor;

[0027] The theoretical condensation temperature model is:

[0028]

[0029] Wherein, m is the mass flow rate of water on the condensation side, t1 and t2 are the inlet and outlet temperatures of water on the condensation side, F c is the heat exchange area on the condensation side, K is the heat exchange coefficient on the condensation side, T c is the theoretical condensation temperature, β is the correction factor; c is the specific heat capacity of water.

[0030] Furthermore, the actual exhaust superheat is equal to the compressor exhaust temperature minus the actual condensation temperature.

[0031] In a second aspect, an expansion valve control system considering the constitutive configuration of an air source heat pump is proposed, including:

[0032] A data acquisition module, configured to acquire the ambient temperature, the inlet and outlet temperatures of water on the condensation side and the mass flow rate of water, as well as the compressor frequency, the exhaust temperature and the exhaust pressure;

[0033] The theoretical temperature and actual exhaust superheat calculation module is used to calculate the theoretical evaporation temperature and the theoretical condensation temperature according to the acquired data and the air source heat pump constitutive configuration parameters, in accordance with the theoretical evaporation temperature model and the theoretical condensation temperature model; calculate the actual condensation temperature based on the compressor discharge pressure and refrigerant physical property parameters, and calculate the actual exhaust superheat according to the actual condensation temperature;

[0034] The temperature deviation calculation module is used to calculate the temperature deviation between the compressor discharge temperature and the exhaust alarm limit temperature;

[0035] The target exhaust superheat calculation module is used to calculate and determine the target exhaust superheat according to the compressor frequency, the theoretical evaporation temperature and the theoretical condensation temperature, in accordance with the target exhaust superheat calculation model when the temperature deviation is greater than or equal to the set temperature deviation threshold; among them, the target exhaust superheat calculation model is fitted from the compressor sample data, and the compressor sample data includes the existing theoretical evaporation temperature, compressor frequency, theoretical condensation temperature and the corresponding target exhaust superheat;

[0036] The expansion valve control module is used to control the exhaust superheat of the expansion valve according to the target exhaust superheat and the actual exhaust superheat.

[0037] In a third aspect, a computer device is proposed, and the device includes:

[0038] A processor, adapted to execute a computer program;

[0039] A computer-readable storage medium, in which a computer program is stored, and when the computer program is executed by the processor, it implements the expansion valve control method considering the air source heat pump constitutive configuration proposed in the first aspect.

[0040] In a fourth aspect, a computer-readable storage medium is proposed, and the computer-readable storage medium stores a computer program, and the computer program is adapted to be loaded and executed by a processor to implement the expansion valve control method considering the air source heat pump constitutive configuration proposed in the first aspect.

[0041] In a fifth aspect, a computer program product is proposed, and the computer program product includes a computer program, and when the computer program is executed by a processor, it implements the expansion valve control method considering the air source heat pump constitutive configuration proposed in the first aspect.

[0042] Compared with the prior art, the beneficial effects of the present invention are:

[0043] The expansion valve control method and system considering the constitutive configuration of an air source heat pump proposed by the present invention. The method obtains the ambient temperature, the inlet water temperature, the outlet water temperature and the mass flow rate of water on the condensing side, as well as the compressor frequency, the exhaust gas temperature and the exhaust gas pressure. Then, according to the obtained data and the air source heat pump constitutive configuration parameters, the theoretical evaporation temperature, the theoretical condensation temperature and the actual exhaust gas superheat degree are calculated and determined. After that, the temperature deviation between the compressor exhaust gas temperature and the exhaust gas alarm limit temperature is calculated. When the temperature deviation is greater than or equal to the set temperature deviation threshold, the target exhaust gas superheat degree is calculated and determined, and the expansion valve is controlled for exhaust gas superheat degree. When controlling the expansion valve, the air source heat pump constitutive configuration parameters are considered, which improves the control accuracy of the expansion valve, prevents system oscillation, and ensures the safe and efficient operation of the unit.

[0044] Advantages of additional aspects of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The specification drawings forming a part of this application are used to provide a further understanding of this application. The schematic embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation of this application.

[0046] Figure 1 Flowchart of the expansion valve control method considering the constitutive configuration of an air source heat pump disclosed for the embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0047] The present invention will be further described below in conjunction with the drawings and embodiments.

[0048] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs.

[0049] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to this application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0050] Embodiment 1

[0051] During the operation of an air-source heat pump system, the exhaust pressure is usually relatively high, and the exhaust superheat degree is relatively large compared to the suction superheat degree. Controlling the expansion valve opening by the exhaust superheat degree can reduce the requirements for the measurement point accuracy and the control difficulty, thereby improving the system operation performance. However, in the related technologies, when controlling the expansion valve by the exhaust superheat degree, the influence of the constitutive configuration parameters of the air-source heat pump is not considered, resulting in a low control accuracy of the expansion valve.

[0052] In order to improve the control accuracy of the expansion valve, in this embodiment, a control method for the expansion valve considering the constitutive configuration of the air-source heat pump is disclosed, as Figure 1 shown, including:

[0053] S1: Obtain the ambient temperature, the inlet water temperature, the outlet water temperature and the mass flow rate of water on the condensing side, and the compressor frequency, the exhaust temperature and the exhaust pressure.

[0054] In this embodiment, by obtaining in real time the ambient temperature T a of the air-source heat pump, the inlet water temperature t1, the outlet water temperature t2 and the mass flow rate m of water on the condensing side, and the compressor frequency n, the exhaust temperature T out and the exhaust pressure P con , the expansion valve is regulated.

[0055] S2: According to the obtained data and the constitutive configuration parameters of the air-source heat pump, calculate the theoretical evaporation temperature and the theoretical condensation temperature according to the theoretical evaporation temperature model and the theoretical condensation temperature model; calculate the actual condensation temperature according to the compressor exhaust pressure and the refrigerant physical property parameters, and calculate the actual exhaust superheat degree according to the actual condensation temperature.

[0056] Among them, the constitutive configuration parameters of the air-source heat pump include the outdoor heat exchange area F e on the evaporation side, F e can take values from 0 to 1500 m 2 , the rated air volume G of the outdoor fan, G can take values from 0 to 200 m 3 / s, the displacement volume V o of the compressor, V o can be obtained from the compressor sample, V o can take values from 0 to 0.3 m 3 / rev, the heat transfer coefficient K on the condensing side, K can take values from 0 to 2000 W / (m 2 ·K) and the heat exchange area F c on the condensing side, F c can take values from 0 to 1500 m 2 .

[0057] In this embodiment, according to the ambient temperature T a , the compressor frequency n and the rated air volume G of the outdoor fan and the outdoor heat exchange area F on the evaporation side in the constitutive configuration parameters of the air-source heat pumpe , the stroke volume V of the compressor o and the theoretical evaporation temperature model are used to calculate and determine the theoretical evaporation temperature T e , where the theoretical evaporation temperature model is derived from the ASHP defrosting semi-empirical model, and the theoretical evaporation temperature model is:

[0058]

[0059] In the formula, T a is the ambient temperature, n is the compressor frequency, G is the rated air volume of the outdoor fan, F e is the outdoor heat exchange area on the evaporation side, V o is the stroke volume of the compressor, T e is the theoretical evaporation temperature, and α is a correction coefficient, which is generally determined through experiments.

[0060] According to the mass flow rate m of water on the condensation side, the inlet water temperature t1 and the outlet water temperature t2 of the condensation side, the heat exchange area F on the condensation side in the air source heat pump constitutive configuration parameters c and the condensation side heat exchange coefficient K and the theoretical condensation temperature model are used to calculate and determine the theoretical condensation temperature T c , and the theoretical condensation temperature model is derived from the logarithmic heat exchange temperature difference formula on the condensation side. The theoretical condensation temperature model is:

[0061]

[0062] In the formula, m is the mass flow rate of water on the condensation side, t1 and t2 are the inlet water temperature and the outlet water temperature of the condensation side, F c is the heat exchange area on the condensation side, K is the heat exchange coefficient on the condensation side, T c is the theoretical condensation temperature, β is a correction coefficient, which is generally determined through experiments; c is the specific heat capacity of water, taking 4.2×10 3 J / (kg·K).

[0063] The actual exhaust superheat T dsh is equal to the compressor exhaust temperature T out minus the actual condensation temperature T c，actual ; the actual condensation temperature T c，actual is determined according to the compressor exhaust pressure P con . Specifically:

[0064] T c，actual is equal to the saturation temperature corresponding to the refrigerant compressor exhaust pressure, which is calculated based on the compressor exhaust pressure and the refrigerant physical property parameters.

[0065] T dsh = T out - T c，actual。

[0066] S3: Calculate the temperature deviation between the compressor exhaust temperature and the exhaust alarm limit temperature.

[0067] Temperature deviation = T out_max - T out 。

[0068] Where, T out_max is the exhaust alarm limit temperature.

[0069] S4: When the temperature deviation is greater than or equal to the set temperature deviation threshold, calculate and determine the target exhaust superheat degree according to the compressor frequency, the theoretical evaporation temperature, and the theoretical condensation temperature, in accordance with the target exhaust superheat degree calculation model; where the target exhaust superheat degree calculation model is fitted from the compressor sample data, and the compressor sample data includes the existing theoretical evaporation temperature, compressor frequency, theoretical condensation temperature, and the corresponding target exhaust superheat degree.

[0070] That is, when T out_max - T out ≥ a, calculate and determine the target exhaust superheat degree T set_dsh , where the target exhaust superheat degree calculation model is:

[0071] T set_dsh =

[0072] (18.228 - 0.081829n — 0.0049469T e + 0.090717T c + 0.0013215n 2 + 0.029106T e 2 + 0.0085057T c 2 + 0.0013556nT e - 0.0028757nT c - 0.027437T e T c ) × γ _1 In the formula, T set_dsh is the target exhaust superheat degree, T e is the theoretical evaporation temperature, T c is the theoretical condensation temperature, n is the compressor frequency, γ _1 is the correction coefficient, determined through experiments; a is the set temperature deviation threshold, generally taking 0 - 10 °C.

[0073] And when the temperature deviation is less than the set temperature deviation threshold, that is, T out_max - T out < a, perform PID control on the expansion valve according to the target exhaust temperature T set_out .

[0074] Among them, the target exhaust gas temperature is a preset value and can be changed according to actual requirements.

[0075] S5: Control the superheat degree of the expansion valve according to the target exhaust gas superheat degree and the actual exhaust gas superheat degree.

[0076] The process of controlling the superheat degree of the expansion valve according to the target exhaust gas superheat degree and the actual exhaust gas superheat degree includes:

[0077] Calculate the superheat degree error between the actual exhaust gas superheat degree and the target exhaust gas superheat degree, and the superheat degree error = ∣T dsh -T set_dsh ∣;

[0078] When the superheat degree error is greater than the set superheat degree error threshold b, that is, ∣T dsh -T set_dsh ∣ > b, perform PID control on the expansion valve according to the target exhaust gas superheat degree T set_dsh ;

[0079] When the superheat degree error is less than or equal to the set superheat degree error threshold b, that is, ∣T dsh -T set_dsh ∣ ≤ b, the expansion valve is not adjusted and the unit continues to run smoothly.

[0080] Among them, b can generally take 0 - 10 °C.

[0081] In addition, in this embodiment, when controlling the expansion valve according to the target exhaust gas temperature T set_out or according to the target exhaust gas superheat degree T set_dsh , PID is used to control the expansion valve, further improving the control accuracy.

[0082] Taking refrigerant R410A as an example, the expansion valve control method considering the air source heat pump constitutive configuration disclosed in this embodiment is described in detail.

[0083] First, determine that the outdoor heat exchange area F e on the evaporation side is 169 m 2 , the rated air volume G of the outdoor fan is 0.844 m 3 / s, the stroke volume V o of the compressor is 1.1×10 -4 m 3 / rev, the heat transfer coefficient K on the condensation side is 1300 w / (m 2 ·K), the heat exchange area F c on the condensation side is 16.8 m 2 , the exhaust gas alarm limit temperature T out_max is 115 °C and the target exhaust gas temperature T set_outis 110 °C.

[0084] The ambient temperature T is monitored a is -12 °C, the compressor discharge temperature T out is 103.92 °C, the compressor discharge pressure P con is 2501 kPa, the inlet water temperature t1 on the condensing side is 35.26 °C, the outlet water temperature t2 on the condensing side is 40.72 °C, the compressor frequency n is 100 Hz, and the mass flow rate m of water on the condensing side is 2.05 m / s.

[0085] According to the formula calculate the theoretical evaporation temperature T e is -18.65 °C, the theoretical condensing temperature T c is 40.96 °C, where α is taken as 0.6, β is taken as 1.1, and c is the specific heat capacity of water taken as 4.2×10 3 J / (kg·K).

[0086] Determine the actual condensing temperature T according to the compressor discharge pressure c，actual = 43 °C, and according to T dsh = T out - T c，actual , calculate the actual discharge superheat degree T dsh in real time, which is 60.88 °C.

[0087] If a is taken as 5 °C, then T out_max - T out = 11.07 °C ≥ a. According to the model T set_dsh = (18.228 - 0.081829n — 0.0049469T e + 0.090717T c + 0.0013215n 2 + 0.029106T e 2 + 0.0085057T c 2 + 0.0013556nT e - 0.0028757nT c - 0.027437T e T c ) × γ _1 , where γ _1 is taken as 1, calculate the target discharge superheat degree T set_dsh which is 60.25 °C.

[0088] Further calculate |T dsh - T set_dsh | = 1.62, and b is taken as 2 °C. It can be seen that |T dsh - T set_dshIf ∣T

[0089] If ∣T dsh -T set_dsh ∣≤b, the expansion valve does not adjust, and the unit continues to run smoothly. set_dsh If ∣T out_max -T out ∣>b, the expansion valve is controlled according to the target discharge superheat T set_out ; if T

[0090] The expansion valve control method considering the air source heat pump constitution configuration disclosed in this embodiment comprehensively considers the influence of multi-dimensional parameters such as air source heat pump constitution configuration parameters, compressor frequency, ambient temperature, and water supply temperature when calculating the theoretical evaporation temperature and the theoretical condensation temperature, and has high calculation accuracy; when using the accurate theoretical evaporation temperature and theoretical condensation temperature to calculate the target discharge superheat, and then controlling the expansion valve according to the target discharge superheat, the accuracy of the expansion valve discharge superheat control is improved.

[0091] In addition, the exhaust superheat control adopted in this embodiment can effectively avoid the problems of system oscillation and too high exhaust temperature caused by insufficient accuracy of the pressure sensor in a low-temperature environment, improve the control accuracy, ensure the safe and efficient operation of the system, and has strong applicability.

[0092] Embodiment 2

[0093] In this embodiment, an expansion valve control system considering the air source heat pump constitution configuration is disclosed, including:

[0094] A data acquisition module for acquiring the ambient temperature, the inlet temperature, the outlet temperature and the mass flow rate of water on the condensation side, as well as the compressor frequency, the exhaust temperature and the exhaust pressure;

[0095] A theoretical temperature and actual exhaust superheat calculation module for calculating the theoretical evaporation temperature and the theoretical condensation temperature according to the acquired data and the air source heat pump constitution configuration parameters according to the theoretical evaporation temperature model and the theoretical condensation temperature model; calculating the actual condensation temperature according to the compressor exhaust pressure and the refrigerant physical property parameters, and calculating the actual exhaust superheat according to the actual condensation temperature;

[0096] A temperature deviation calculation module for calculating the temperature deviation between the compressor exhaust temperature and the exhaust alarm limit temperature;

[0097] A target discharge superheat calculation module, configured to calculate and determine a target discharge superheat according to a compressor frequency, a theoretical evaporation temperature, and a theoretical condensation temperature according to a target discharge superheat calculation model when a temperature deviation is greater than or equal to a set temperature deviation threshold; wherein, the target discharge superheat calculation model is fitted from compressor sample data, and the compressor sample data includes existing theoretical evaporation temperatures, compressor frequencies, theoretical condensation temperatures, and corresponding target discharge superheats;

[0098] An expansion valve control module, configured to perform discharge superheat control on the expansion valve according to the target discharge superheat and the actual discharge superheat.

[0099] The present invention also discloses a computer device, which includes:

[0100] A processor, adapted to execute a computer program;

[0101] A computer-readable storage medium, in which a computer program is stored, and when the computer program is executed by the processor, the expansion valve control method disclosed in Embodiment 1 considering the air source heat pump constitutive configuration is implemented.

[0102] The present invention also discloses a computer-readable storage medium, which stores a computer program, and the computer program is adapted to be loaded and executed by a processor to implement the expansion valve control method disclosed in Embodiment 1 considering the air source heat pump constitutive configuration.

[0103] The present invention also discloses a computer program product, which includes a computer program, and when the computer program is executed by a processor, the expansion valve control method disclosed in Embodiment 1 considering the air source heat pump constitutive configuration is implemented.

[0104] The method disclosed in Embodiment 1 can be directly embodied as being executed by a hardware processor, or by a combination of hardware and software modules in the processor. The software modules can be located in mature storage media in the art such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, registers, etc. This storage medium is located in the memory, and the processor reads the information in the memory and combines its hardware to complete the steps of the above method. To avoid repetition, it will not be described in detail here.

[0105] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with this embodiment can be implemented by electronic hardware or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods for each specific application to implement the described functions, but such implementation should not be considered to exceed the scope of this application.

[0106] Although the specific implementation manners of the present invention have been described above in conjunction with the accompanying drawings, it is not a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications or deformations that can be made without creative efforts on the basis of the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. An expansion valve control method considering the constitutive configuration of an air source heat pump, characterized in that: include: Obtain the ambient temperature, the inlet and outlet water temperatures and water mass flow rate on the condensing side, as well as the compressor frequency, exhaust temperature and exhaust pressure; According to the acquired data and the constitutive configuration parameters of the air source heat pump, the theoretical evaporation temperature and the theoretical condensation temperature are calculated according to the theoretical evaporation temperature model and the theoretical condensation temperature model; The theoretical evaporation temperature model is: Where, T a is the ambient temperature, n is the compressor frequency, G is the rated air volume of the outdoor fan, F e is the outdoor heat exchange area on the evaporation side, V o is the compressor stroke volume, T e is the theoretical evaporation temperature, α is the correction coefficient; The theoretical condensation temperature model is: Where m is the mass flow rate of water on the condensing side, t1 and t2 are the inlet and outlet water temperatures on the condensing side, and F c is the heat exchange area on the condensation side, K is the heat exchange coefficient on the condensation side, T c is the theoretical condensation temperature, β is the correction coefficient; c is the specific heat capacity of water; Calculate the actual condensing temperature based on the compressor exhaust pressure and refrigerant physical parameters, and calculate the actual exhaust superheat based on the actual condensing temperature; Calculate the temperature deviation between the compressor exhaust temperature and the exhaust alarm limit temperature; When the temperature deviation is greater than or equal to the set temperature deviation threshold, the target exhaust superheat is calculated and determined according to the compressor frequency, theoretical evaporation temperature and theoretical condensation temperature and the target exhaust superheat calculation model; wherein the target exhaust superheat calculation model is fitted by the compressor sample data, and the compressor sample data includes the existing theoretical evaporation temperature, compressor frequency, theoretical condensation temperature and the corresponding target exhaust superheat; The target exhaust superheat calculation model is: T set_dsh ＝ (18.228-0.081829n—0.0049469T e +0.090717T c +0.0013215n 2 +0.029106T e 2 +0.0085057T c 2 +0.0013556nT e -0.0028757nT c -0.027437T e T c )×γ _1 Where, T set_dsh is the target exhaust superheat, T e is the theoretical evaporation temperature, T c is the theoretical condensing temperature, n is the compressor frequency, γ _1 is the correction factor; According to the target exhaust superheat and the actual exhaust superheat, the expansion valve is controlled for exhaust superheat; The process of controlling the exhaust superheat of the expansion valve according to the target exhaust superheat and the actual exhaust superheat includes: Calculating the superheat error between the actual exhaust superheat and the target exhaust superheat; When the superheat error is greater than the set superheat error threshold, the expansion valve is PID controlled according to the target exhaust superheat; when the superheat error is less than or equal to the set superheat error threshold, the system continues to operate smoothly; When the temperature deviation is less than the set temperature deviation threshold, the expansion valve is PID controlled according to the target exhaust temperature.

2. The expansion valve control method considering the constitutive configuration of an air source heat pump according to claim 1, characterized in that: The actual discharge superheat is equal to the compressor discharge temperature minus the actual condensing temperature.

3. An expansion valve control system considering the constitutive configuration of an air source heat pump, characterized in that: include: A data acquisition module is used to obtain the ambient temperature, the inlet and outlet water temperatures and the water mass flow rate on the condensing side, as well as the compressor frequency, exhaust temperature and exhaust pressure; Theoretical temperature and actual exhaust superheat calculation module is used to calculate the theoretical evaporation temperature and theoretical condensation temperature according to the acquired data and the constitutive configuration parameters of the air source heat pump, according to the theoretical evaporation temperature model and the theoretical condensation temperature model; calculate the actual condensation temperature according to the compressor exhaust pressure and refrigerant physical parameters, and calculate the actual exhaust superheat according to the actual condensation temperature; The theoretical evaporation temperature model is: Where, T a is the ambient temperature, n is the compressor frequency, G is the rated air volume of the outdoor fan, F e is the outdoor heat exchange area on the evaporation side, V o is the compressor stroke volume, T e is the theoretical evaporation temperature, α is the correction coefficient; The theoretical condensation temperature model is: Where m is the mass flow rate of water on the condensing side, t1 and t2 are the inlet and outlet water temperatures on the condensing side, and F c is the heat exchange area on the condensation side, K is the heat exchange coefficient on the condensation side, T c is the theoretical condensation temperature, β is the correction coefficient; c is the specific heat capacity of water; A temperature deviation calculation module is used to calculate the temperature deviation between the compressor exhaust temperature and the exhaust alarm limit temperature; The target exhaust superheat calculation module is used to calculate and determine the target exhaust superheat according to the compressor frequency, theoretical evaporation temperature and theoretical condensation temperature according to the target exhaust superheat calculation model when the temperature deviation is greater than or equal to the set temperature deviation threshold; wherein the target exhaust superheat calculation model is fitted by the compressor sample data, and the compressor sample data includes the existing theoretical evaporation temperature, compressor frequency, theoretical condensation temperature and the corresponding target exhaust superheat; The target exhaust superheat calculation model is: T set_dsh ＝ (18.228-0.081829n—0.0049469T e +0.090717T c +0.0013215n 2 +0.029106T e 2 +0.0085057T c 2 +0.0013556nT e -0.0028757nT c -0.027437T e T c )×γ _1 Where, T set_dsh is the target exhaust superheat, T e is the theoretical evaporation temperature, T c is the theoretical condensing temperature, n is the compressor frequency, γ _1 is the correction factor; An expansion valve control module, used for controlling the exhaust superheat of the expansion valve according to the target exhaust superheat and the actual exhaust superheat; The process of controlling the exhaust superheat of the expansion valve according to the target exhaust superheat and the actual exhaust superheat includes: Calculating the superheat error between the actual exhaust superheat and the target exhaust superheat; When the superheat error is greater than the set superheat error threshold, the expansion valve is PID controlled according to the target exhaust superheat; when the superheat error is less than or equal to the set superheat error threshold, the system continues to operate smoothly; When the temperature deviation is less than the set temperature deviation threshold, the expansion valve is PID controlled according to the target exhaust temperature.

4. An electronic device, characterized in that: The device comprises: a processor adapted to execute a computer program; A computer-readable storage medium, wherein a computer program is stored in the computer-readable storage medium, and when the computer program is executed by the processor, the expansion valve control method considering the constitutive configuration of the air source heat pump as described in any one of claims 1-2 is implemented.

5. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and the computer program is suitable for being loaded by a processor and executing the expansion valve control method considering the constitutive configuration of an air source heat pump as described in any one of claims 1-2.

6. A computer program product, characterized in that The computer program product includes a computer program, and when the computer program is executed by a processor, the expansion valve control method considering the constitutive configuration of the air source heat pump as described in any one of claims 1-2 is implemented.

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