Control method and device of heat pump system, computer equipment and storage medium

Abstract

The invention relates to a control method and device of a heat pump system, computer equipment and a storage medium. In the starting process of the heat pump system, the first controller is used for controlling the opening degree of the electronic expansion valve based on the exhaust temperature set value and the exhaust temperature. In the starting process of the heat pump system, whether the heat pump system enters a stable operation state with system parameters reaching dynamic balance or not is judged. And in the stable operation state of the heat pump system, the second controller is used for controlling the opening degree of the electronic expansion valve based on the minimum stable superheat degree and the superheat degree. Oscillation of the superheat degree of the evaporator can be effectively restrained through control over the starting process, the adjusting time is shortened, and the operation stability of the heat pump system is improved. The control in the stable operation stage can enable the superheat degree of the evaporator of the heat pump system to be close to the minimum stable superheat degree, more refrigerants can participate in phase change heat absorption, the heating capacity of the refrigerants is improved, the power consumption of a compressor is reduced, and the energy efficiency ratio of the heat pump system is increased.

Description

Technical Field

[0001] This application relates to the field of heat pump system control, and in particular, to a control method, device, computer device, and storage medium for a heat pump system. Background Art

[0002] As an energy-efficient heating and cooling system, the heat pump system is widely used in fields such as construction and industry. The magnetic levitation heat pump system uses magnetic levitation bearings to replace the mechanical bearings in the traditional heat pump system. With the advantages of no mechanical contact, no friction loss, and low vibration and noise of the magnetic levitation bearings, it solves the problems of energy loss caused by mechanical friction of the mechanical bearings and high noise caused by mechanical vibration in the traditional heat pump system.

[0003] However, whether it is a traditional heat pump system using mechanical bearings or a magnetic levitation heat pump system using magnetic levitation bearings, the relationship between the opening degree of the electronic expansion valve and the refrigerant flow rate is a non-linear relationship. Proportional-Integral-Derivative (PID) control is based on linear control theory and is usually applicable to single-input single-output systems. For multivariable control, complex decoupling strategies need to be designed, and the control effect for non-linear systems is poor. It requires complex parameter tuning or piecewise linearization processing, and the output parameters may oscillate due to improper parameter tuning. Therefore, using a PID controller to control the opening degree of the electronic expansion valve of the heat pump system will cause system oscillation and affect the stability of system operation. Summary of the Invention

[0004] To overcome the problems existing in the related art, this application provides a control method, device, computer device, and storage medium for a heat pump system.

[0005] According to the first aspect of the embodiments of this application, a control method for a heat pump system is provided. The heat pump system includes an electronic expansion valve. The control method includes:

[0006] During the startup process of the heat pump system, use a first controller to control the opening degree of the electronic expansion valve, and determine whether the heat pump system enters a stable operation state, where the stable operation state refers to a state in which the system parameters of the heat pump system reach dynamic equilibrium. The first controller controls the opening degree of the electronic expansion valve based on the exhaust temperature set value and the exhaust temperature of the compressor of the heat pump system;

[0007] In response to the heat pump system entering the stable operation state, the opening degree of the electronic expansion valve is controlled by using a second controller, where the second controller controls the opening degree of the electronic expansion valve based on the minimum stable superheat degree corresponding to the current ambient temperature of the environment where the heat pump system is located and the superheat degree of the evaporator of the heat pump system.

[0008] In some exemplary embodiments of the present application, determining whether the heat pump system enters the stable operation state includes:

[0009] Obtain the initial water temperature when the heat pump system starts;

[0010] Obtain the current water temperature of the heat pump system;

[0011] Compare the difference between the current water temperature and the initial water temperature with a first preset value;

[0012] In response to the difference between the current water temperature and the initial water temperature being greater than the first preset value, determine that the heat pump system enters the stable operation state;

[0013] In response to the difference between the current water temperature and the initial water temperature being less than or equal to the first preset value, determine that the heat pump system does not enter the stable operation state;

[0014] Wherein, both the initial water temperature and the current water temperature are the temperatures of the circulating water on the user side in the heat pump system.

[0015] In some exemplary embodiments of the present application, using a first controller to control the opening degree of the electronic expansion valve includes:

[0016] Obtain the temperature at the exhaust port of the compressor of the heat pump system as the exhaust temperature;

[0017] Take the difference between the exhaust temperature set value and the exhaust temperature as the first input parameter;

[0018] Take the change rate of the difference between the exhaust temperature set value and the exhaust temperature as the second input parameter;

[0019] Input the first input parameter and the second input parameter into the first controller, and control the opening degree of the electronic expansion valve according to the first output parameter of the first controller, where the first output parameter is used to characterize the adjustment amount of the opening degree of the electronic expansion valve.

[0020] In some exemplary embodiments of the present application, using a second controller to control the opening degree of the electronic expansion valve includes:

[0021] Obtain the minimum stable superheat degree;

[0022] Obtain the difference between the refrigerant gas temperature at the outlet of the evaporator of the heat pump system and the refrigerant saturation temperature at the pressure at the outlet of the evaporator as the superheat degree;

[0023] Take the difference between the minimum stable superheat degree and the superheat degree as the third input parameter;

[0024] Take the change rate of the difference between the minimum stable superheat degree and the superheat degree as the fourth input parameter;

[0025] Input the third input parameter and the fourth input parameter into the second controller, and control the opening degree of the electronic expansion valve according to the second output parameter of the second controller, where the second output parameter is used to characterize the adjustment amount of the opening degree of the electronic expansion valve.

[0026] In some exemplary embodiments of the present application, the obtaining of the minimum stable superheat degree includes:

[0027] Use the current ambient temperature of the environment where the heat pump system is located, and determine the minimum stable superheat degree according to a preset ambient temperature - minimum stable superheat degree curve.

[0028] In some exemplary embodiments of the present application, controlling the opening degree of the electronic expansion valve according to the first output parameter or the second output parameter includes:

[0029] Input the first output parameter or the second output parameter into an electronic expansion valve driver;

[0030] Control the opening degree of the electronic expansion valve according to the third output parameter of the electronic expansion valve driver;

[0031] Wherein, the third output parameter is a pulse modulation signal.

[0032] In some exemplary embodiments of the present application, the exhaust temperature is negatively correlated with the opening degree of the electronic expansion valve, and the superheat degree is negatively correlated with the opening degree of the electronic expansion valve.

[0033] According to the second aspect of the embodiments of the present application, there is provided a control device for a heat pump system, the heat pump system includes an electronic expansion valve, and the control device includes:

[0034] A start-up stage control module, configured to control the opening degree of the electronic expansion valve using a first controller during the start-up process of the heat pump system, where the first controller controls the opening degree of the electronic expansion valve based on an exhaust temperature set value and the exhaust temperature of the compressor of the heat pump system;

[0035] An operating state determination module is configured to determine whether the heat pump system enters a stable operating state during the startup process of the heat pump system, where the stable operating state refers to a state in which the system parameters of the heat pump system reach dynamic equilibrium;

[0036] A stable operating stage control module is configured to, in response to the heat pump system entering the stable operating state, use a second controller to control the opening degree of the electronic expansion valve, where the second controller controls the opening degree of the electronic expansion valve based on the minimum stable superheat degree corresponding to the current ambient temperature of the environment where the heat pump system is located and the superheat degree of the evaporator of the heat pump system.

[0037] According to a third aspect of the embodiments of the present application, a computer device is provided, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the steps of the control method of the heat pump system as described in the first aspect are implemented.

[0038] According to a fourth aspect of the embodiments of the present application, a non-temporary computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the control method of the heat pump system as described in the first aspect are implemented.

[0039] The technical solutions provided by the embodiments of the present application may include the following beneficial effects: During the startup process of the heat pump system, by using a first controller to control the opening degree of the electronic expansion valve according to the exhaust temperature set value and the exhaust temperature of the compressor of the heat pump system, the oscillation of the superheat degree of the evaporator can be effectively suppressed, the adjustment time is shortened, and the operating stability of the heat pump system is improved. After the heat pump system enters the stable operating stage, by using a second controller to control the opening degree of the electronic expansion valve according to the minimum stable superheat degree corresponding to the current ambient temperature of the environment where the heat pump system is located and the superheat degree of the evaporator of the heat pump system, the superheat degree of the evaporator of the heat pump system can approach the minimum stable superheat degree, more refrigerant can participate in phase change heat absorption, the heating capacity of the refrigerant is improved, the power consumption of the compressor is reduced, and the energy efficiency ratio of the heat pump system is improved.

[0040] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings herein are incorporated into the specification and constitute a part of this specification, showing embodiments consistent with the present invention and used together with the specification to explain the principles of the present invention.

[0042] Figure 1 It is a flowchart of a control method of a heat pump system shown according to an exemplary embodiment of the present application.

[0043] Figure 2 It is a schematic diagram showing the control of the opening degree of an electronic expansion valve using a first controller according to an exemplary embodiment of the present application.

[0044] Figure 3 It is a flowchart showing the determination of whether a heat pump system enters a stable operation state according to an exemplary embodiment of the present application.

[0045] Figure 4 It is a flowchart showing the control of the opening degree of an electronic expansion valve using a first controller according to an exemplary embodiment of the present application.

[0046] Figure 5 It is a schematic diagram showing the control of the opening degree of an electronic expansion valve using a second controller according to an exemplary embodiment of the present application.

[0047] Figure 6 It is a flowchart showing the control of the opening degree of an electronic expansion valve using a second controller according to an exemplary embodiment of the present application.

[0048] Figure 7 It is a flowchart showing the control of the opening degree of an electronic expansion valve according to a first output parameter or a second output parameter according to an exemplary embodiment of the present application.

[0049] Figure 8 It is a flowchart showing another control method of a heat pump system according to an exemplary embodiment of the present application.

[0050] Figure 9 It is a block diagram showing a control device of a heat pump system according to an exemplary embodiment of the present application.

[0051] Figure 10 It is a block diagram showing a computer device according to an exemplary embodiment of the present application. Detailed Embodiments

[0052] Here, exemplary embodiments will be described in detail, and examples are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0053] As an energy-efficient heating and cooling system, the heat pump system has been widely used in fields such as construction and industry. The magnetic levitation heat pump system uses magnetic levitation bearings to replace the mechanical bearings in the traditional heat pump system. With the advantages of non-mechanical contact, no friction loss, and low vibration and noise of the magnetic levitation bearings, it solves the problems of energy loss caused by mechanical friction of the mechanical bearings and high noise caused by mechanical vibration in the traditional heat pump system.

[0054] However, whether it is a traditional heat pump system using mechanical bearings or a magnetic levitation heat pump system using magnetic levitation bearings, the relationship between the opening degree of the electronic expansion valve and the refrigerant flow rate is a non-linear relationship. PID control is based on linear control theory and is usually applicable to single-input single-output systems. For multi-variable control, complex decoupling strategies need to be designed, and the control effect for non-linear systems is poor. It requires complex parameter tuning or piecewise linearization processing, and output parameter oscillations may occur due to improper parameter tuning. Therefore, using a PID controller to control the opening degree of the electronic expansion valve of the heat pump system will cause system oscillations and affect the stability of system operation.

[0055] To solve the above technical problems, the present application provides a control method, device, computer device, and storage medium for a heat pump system. During the startup process of the heat pump system, a first controller is used to control the opening degree of the electronic expansion valve according to the exhaust temperature set value and the exhaust temperature of the compressor of the heat pump system, which can effectively suppress the oscillation of the superheat degree of the evaporator, shorten the adjustment time, and improve the stability of the heat pump system operation. After the heat pump system enters the stable operation stage, a second controller is used to control the opening degree of the electronic expansion valve according to the minimum stable superheat degree corresponding to the current ambient temperature of the environment where the heat pump system is located and the superheat degree of the evaporator of the heat pump system, which can make the superheat degree of the evaporator of the heat pump system approach the minimum stable superheat degree, enable more refrigerant to participate in phase change heat absorption, improve the heating capacity of the refrigerant, reduce the power consumption of the compressor, and improve the energy efficiency ratio of the heat pump system.

[0056] An exemplary embodiment of the present application provides a control method for a heat pump system, as Figure 1 shown. The control method for the heat pump system shown in this exemplary embodiment includes:

[0057] S101. During the startup process of the heat pump system, use a first controller to control the opening degree of the electronic expansion valve, and determine whether the heat pump system enters the stable operation state.

[0058] The stable operation state refers to the state where the system parameters of the heat pump system reach dynamic equilibrium. The first controller controls the opening degree of the electronic expansion valve based on the exhaust temperature set value and the exhaust temperature of the compressor of the heat pump system.

[0059] A heat pump system is a system that transfers low-grade heat energy in a low-temperature environment (such as air, soil, groundwater, etc.) to a high-temperature environment by consuming a small amount of electrical energy or other high-grade energy sources.

[0060] The startup process of the heat pump system refers to the process from when the heat pump system is powered on to when it operates stably.

[0061] The electronic expansion valve is a key throttling device in the heat pump system, used to precisely regulate the refrigerant flow rate. The opening of the electronic expansion valve is controlled by an electronic signal. The opening of the electronic expansion valve refers to the displacement of the valve needle or valve core inside the valve body, which is used to adjust the cross-sectional area of the passage through which the refrigerant flows through the valve body, thereby precisely controlling the refrigerant flow rate.

[0062] The stable operating state of the heat pump system refers to the state where the system parameters of the heat pump system reach a dynamic balance, that is, key parameters such as the energy input and output of the heat pump system, the refrigerant flow rate and pressure, and the temperature and heat exchange reach a relatively balanced state. However, there are still continuous microscopic regulations inside the system (such as fine-tuning the opening of the electronic expansion valve and changing the compressor frequency, etc.) to cope with small external disturbances (such as environmental temperature changes and load fluctuations).

[0063] The exhaust temperature of the compressor of the heat pump system is the temperature of the refrigerant gas at the outlet of the compressor during the operation of the compressor of the heat pump system.

[0064] The exhaust temperature set value refers to the upper limit value of the temperature of the refrigerant gas discharged by the compressor.

[0065] The first controller controls the opening of the electronic expansion valve based on the exhaust temperature set value and the exhaust temperature of the compressor of the heat pump system. It can be based on the difference between the exhaust temperature set value and the exhaust temperature, and the change rate of the difference between the exhaust temperature set value and the exhaust temperature to control the opening of the electronic expansion valve.

[0066] The first controller can be a controller based on a fuzzy control algorithm. The fuzzy control algorithm is an intelligent control method based on fuzzy logic. It imitates the fuzziness of human thinking and processes imprecise or non-linear system inputs through language rules to output continuous control signals. Different from PID control, fuzzy control does not require an accurate mathematical model and is especially suitable for complex, non-linear or difficult-to-model systems.

[0067] The fuzzy rules of the first controller are shown in Table 1.

[0068] The fuzzy rules of the first controller can also be other feasible rules.

[0069] In Table 1, NB indicates that the input parameter is far lower than the target value or the output parameter indicates the maximum reverse action. NM indicates that the input parameter is significantly lower than the target value or the output parameter indicates a medium reverse action. NS indicates that the input parameter is slightly lower than the target value or the output parameter indicates a slight reverse action. ZO indicates that the input parameter is close to or equal to the target value or the output parameter indicates no action. PS indicates that the input parameter is slightly higher than the target value or the output parameter indicates a slight forward action. PM indicates that the input parameter is significantly higher than the target value or the output parameter indicates a medium forward action. PB indicates that the input parameter is far higher than the target value or the output parameter indicates the maximum forward action.

[0070] For example, in Table 1, when the difference between the exhaust gas temperature set value and the exhaust gas temperature is far lower than the target value and the change rate of the difference between the exhaust gas temperature set value and the exhaust gas temperature is far lower than the target value, the output parameter characterizes a slight reverse adjustment of the opening degree of the electronic expansion valve.

[0071] Fuzzy rule table of the first controller in Table 1

[0072]

[0073] Figure 2 is a schematic diagram of using the first controller to control the opening degree of the electronic expansion valve based on the difference between the exhaust gas temperature set value and the exhaust gas temperature, and the change rate of the difference between the exhaust gas temperature set value and the exhaust gas temperature. As Figure 2 shown, fuzzy control includes three links: fuzzy processing, fuzzy inference operation, and defuzzification conversion. In the fuzzy processing link, the first controller maps the difference between the exhaust gas temperature set value and the exhaust gas temperature, and the change rate of the difference between the exhaust gas temperature set value and the exhaust gas temperature from their original numerical domains to a preset fuzzy domain through quantization processing. Subsequently, combined with the membership function and fuzzy language variables, the precise input quantity is subjected to fuzzy characterization conversion, that is, both the difference between the exhaust gas temperature set value and the exhaust gas temperature, and the change rate of the difference between the exhaust gas temperature set value and the exhaust gas temperature are converted from the original precise numerical values to one of the seven fuzzy values such as NB, NM, NS, ZO, PS, PM, PB shown in Table 1. In the fuzzy inference operation link, the first controller, based on the Mamdani-type inference mechanism, derives the fuzzy output quantity by parsing the preset if-then fuzzy rules, that is, uses Table 1 to find the fuzzy output quantity according to the fuzzy value corresponding to the difference between the exhaust gas temperature set value and the exhaust gas temperature, and the fuzzy value corresponding to the change rate of the difference between the exhaust gas temperature set value and the exhaust gas temperature. In the defuzzification conversion link, the first controller converts the fuzzy output quantity into a precise control parameter to control the opening degree of the electronic expansion valve. The exhaust gas temperature is negatively correlated with the opening degree of the electronic expansion valve. After adjusting the opening degree of the electronic expansion valve, the exhaust gas temperature will change, then calculate the difference between the exhaust gas temperature set value and the exhaust gas temperature, and calculate the change rate of the difference, and then perform the next fuzzy control.

[0074] The exhaust temperature is negatively correlated with the opening degree of the electronic expansion valve. That is, under the normal operating conditions of the heat pump system, when the opening degree of the electronic expansion valve increases, the temperature of the refrigerant gas at the outlet of the compressor decreases, and when the opening degree of the electronic expansion valve decreases, the temperature of the refrigerant gas at the outlet of the compressor increases.

[0075] Under different operating conditions, the start-up time of the heat pump system is different. However, during the process from the start-up to the stable operating state, the increment of the water temperature of the circulating water on the user side is consistent. During the start-up process of the heat pump system, it is possible to determine whether the heat pump system has entered the stable operating state based on the increment of the water temperature of the circulating water on the user side. In some exemplary embodiments, as Figure 3 shown, determining whether the heat pump system has entered the stable operating state includes:

[0076] S301. Obtain the initial water temperature when the heat pump system starts up.

[0077] The initial water temperature is the water temperature of the circulating water on the user side in the heat pump system. A temperature sensor provided at the pipeline of the circulating water on the user side can be used to measure the water temperature of the circulating water on the user side at the start of the heat pump system as the initial water temperature. The temperature sensor can be a platinum resistance, a thermocouple, a digital temperature sensor, or other temperature sensors, which are not limited herein.

[0078] S302. Obtain the current water temperature of the heat pump system.

[0079] The current water temperature is the water temperature of the circulating water on the user side in the heat pump system. A temperature sensor provided at the pipeline of the circulating water on the user side can be used to measure the water temperature of the circulating water on the user side at the current moment as the current water temperature.

[0080] S303. Compare the difference between the current water temperature and the initial water temperature with a first preset value.

[0081] The first preset value is the increment value of the water temperature used to determine whether the heat pump system has entered the stable operating state. Comparing the difference between the current water temperature and the initial water temperature with the first preset value can determine whether the heat pump system has entered the stable operating state.

[0082] S304. In response to the difference between the current water temperature and the initial water temperature being greater than the first preset value, determine that the heat pump system has entered the stable operating state.

[0083] In the case where the increment of the current water temperature compared to the initial water temperature is greater than the first preset value, the increment of the water temperature of the circulating water on the user side has reached the increment of the water temperature for entering the stable operating state. At this time, it can be determined that the heat pump system has entered the stable operating state.

[0084] S305. Determine that the heat pump system has not entered the stable operation state in response to the difference between the current water temperature and the initial water temperature being less than or equal to the first preset value.

[0085] When the increment of the water temperature of the circulating water on the user side is less than or equal to the first preset value compared with the initial water temperature, the increment of the water temperature of the circulating water on the user side has not reached the increment of the water temperature for entering the stable operation state. At this time, it can be determined that the heat pump system has not entered the stable operation state.

[0086] Using the increment of the water temperature of the circulating water on the user side to judge whether the heat pump system enters the stable operation state, the data is easy to collect, and the judgment process is simple, reducing the complexity of the control method of the heat pump system.

[0087] In some exemplary embodiments, as Figure 4 shown, controlling the opening degree of the electronic expansion valve using the first controller includes:

[0088] S401. Obtain the temperature at the exhaust port of the compressor of the heat pump system as the exhaust temperature.

[0089] A temperature sensor provided at the exhaust port of the compressor of the heat pump system can be used to measure the temperature of the refrigerant gas at the exhaust port at the current moment as the exhaust temperature. The temperature sensor can be a temperature sensor such as a platinum resistance, a thermocouple, a digital temperature sensor, etc., which is not limited herein.

[0090] S402. Use the difference between the exhaust temperature set value and the exhaust temperature as the first input parameter.

[0091] The exhaust temperature set value can be set when designing the heat pump system. In some examples, the exhaust temperature set value is 125°C. In other examples, the exhaust temperature set value can also be other values.

[0092] In some examples, use the difference between the exhaust temperature set value and the exhaust temperature as Figure 2 the first input parameter of the first controller in

[0093] S403. Use the change rate of the difference between the exhaust temperature set value and the exhaust temperature as the second input parameter.

[0094] The change rate of the difference between the exhaust temperature set value and the exhaust temperature refers to the change speed of the difference between the exhaust temperature set value and the exhaust temperature over time.

[0095] In some examples, use the change rate of the difference between the exhaust temperature set value and the exhaust temperature as Figure 2 the second input parameter of the first controller in

[0096] S404. Input the first input parameter and the second input parameter into the first controller, and control the opening degree of the electronic expansion valve according to the first output parameter of the first controller.

[0097] The first output parameter is used to represent the adjustment amount of the opening degree of the electronic expansion valve.

[0098] In some examples, input the first input parameter and the second input parameter into Figure 2 the first controller in. After receiving the first input parameter and the second input parameter, the first controller performs three processes: fuzzification, fuzzy inference operation, and defuzzification conversion. During this process, the fuzzy rules in Table 1 are used, and the obtained first output parameter is used to represent the adjustment amount of the opening degree of the electronic expansion valve. Control the opening degree of the electronic expansion valve according to this adjustment amount.

[0099] During the startup process of the heat pump system, use the first controller based on the fuzzy control algorithm. According to the exhaust temperature set value and the exhaust temperature of the compressor of the heat pump system, accurately control the opening degree of the electronic expansion valve, which can effectively suppress the oscillation of the superheat degree of the evaporator of the heat pump system, shorten the adjustment time, and improve the stability of the operation of the heat pump system. At the same time, the exhaust temperature is positively correlated with the heating capacity of the evaporator, and the exhaust temperature is negatively correlated with the opening degree of the electronic expansion valve. By reasonably controlling the opening degree of the electronic expansion valve, the heating performance of the heat pump system can be improved.

[0100] S102. In response to the heat pump system entering the stable operation state, use the second controller to control the opening degree of the electronic expansion valve.

[0101] The second controller controls the opening degree of the electronic expansion valve based on the minimum stable superheat degree corresponding to the current ambient temperature of the environment where the heat pump system is located and the superheat degree of the evaporator of the heat pump system.

[0102] The superheat degree of the evaporator of the heat pump system is the difference between the gaseous refrigerant temperature at the outlet of the evaporator of the heat pump system and the refrigerant saturation temperature at the pressure at the outlet of the evaporator.

[0103] The minimum stable superheat degree refers to the lowest allowable superheat degree that the heat pump system can maintain on the premise of ensuring the safe operation of the compressor and avoiding liquid refrigerant from flowing into the compressor. The minimum stable superheat degree value is related to the temperature.

[0104] The superheat of the evaporator of the heat pump system is negatively correlated with the opening degree of the electronic expansion valve. By controlling the opening degree of the electronic expansion valve based on the minimum stable superheat corresponding to the current ambient temperature of the environment of the heat pump system and the superheat of the evaporator of the heat pump system, the superheat of the evaporator of the heat pump system can be made to approach the minimum stable superheat corresponding to the current ambient temperature of the environment where the heat pump system is located, which can extend the two-phase region in the evaporator, enable more refrigerant to participate in phase change heat absorption, enhance the heating capacity of the refrigerant, reduce the power consumption of the compressor, and improve the energy efficiency ratio of the heat pump system.

[0105] The second controller controls the opening degree of the electronic expansion valve based on the minimum stable superheat corresponding to the current ambient temperature of the environment where the heat pump system is located and the superheat of the evaporator of the heat pump system. It can be based on the difference between the minimum stable superheat and the superheat, and the change rate of the difference between the minimum stable superheat and the superheat to control the opening degree of the electronic expansion valve.

[0106] The second controller can be a controller based on the fuzzy control algorithm. The fuzzy rules of the second controller are shown in Table 2. The fuzzy rules of the second controller can also be other feasible rules.

[0107] Table 2 Fuzzy rule table of the second controller

[0108]

[0109] NB indicates that the input parameter is far lower than the target value or the output parameter indicates the maximum reverse action. NM indicates that the input parameter is significantly lower than the target value or the output parameter indicates the medium reverse action. NS indicates that the input parameter is slightly lower than the target value or the output parameter indicates the slight reverse action. ZO indicates that the input parameter is close to or equal to the target value or the output parameter indicates no action. PS indicates that the input parameter is slightly higher than the target value or the output parameter indicates the slight forward action. PM indicates that the input parameter is significantly higher than the target value or the output parameter indicates the medium forward action. PB indicates that the input parameter is far higher than the target value or the output parameter indicates the maximum forward action.

[0110] For example, in Table 2, when the difference between the minimum stable superheat and the superheat is far lower than the target value and the change rate of the difference between the minimum stable superheat and the superheat is far lower than the target value, the output parameter characterizes slightly reverse adjusting the opening degree of the electronic expansion valve.

[0111] Figure 5 It is a schematic diagram of using the second controller to control the opening degree of the electronic expansion valve based on the difference between the minimum stable superheat and the superheat, and the change rate of the difference between the minimum stable superheat and the superheat. As Figure 5As shown, in the fuzzification process, the second controller maps the difference between the minimum stable superheat and the superheat, as well as the change rate of the difference between the minimum stable superheat and the superheat, from their original numerical domains to a preset fuzzy universe of discourse through quantization processing. Subsequently, combined with the membership function and fuzzy linguistic variables, the accurate input quantities are subjected to fuzzy representation conversion, that is, both the difference between the minimum stable superheat and the superheat, and the change rate of the difference between the minimum stable superheat and the superheat are converted from the original accurate numerical values to one of the seven fuzzy values such as NB, NM, NS, ZO, PS, PM, PB shown in Table 2. In the fuzzy inference operation process, the second controller, based on the Mamdani-type inference mechanism, derives the fuzzy output quantity by parsing the preset if-then fuzzy rules, that is, using Table 2, the fuzzy output quantity is found according to the fuzzy value corresponding to the difference between the minimum stable superheat and the superheat, and the fuzzy value corresponding to the change rate of the difference between the minimum stable superheat and the superheat. In the defuzzification conversion process, the second controller converts the fuzzy output quantity into an accurate control parameter to control the opening degree of the electronic expansion valve. The superheat is negatively correlated with the opening degree of the electronic expansion valve. After adjusting the opening degree of the electronic expansion valve, the superheat will change. Then, calculate the difference between the minimum stable superheat and the changed superheat, and calculate the change rate of the difference, and then perform the next fuzzy control.

[0112] The superheat is negatively correlated with the opening degree of the electronic expansion valve. That is to say, under the normal working conditions of the heat pump system, when the opening degree of the electronic expansion valve increases, the superheat of the evaporator of the heat pump system decreases, and when the opening degree of the electronic expansion valve decreases, the superheat of the evaporator of the heat pump system increases.

[0113] In some exemplary embodiments, as Figure 6 shown, using the second controller to control the opening degree of the electronic expansion valve includes:

[0114] S601. Obtain the minimum stable superheat.

[0115] When using the second controller to control the opening degree of the electronic expansion valve, it is necessary to first obtain the minimum stable superheat corresponding to the current ambient temperature of the environment of the heat pump system.

[0116] In some exemplary embodiments, obtaining the minimum stable superheat includes: using the current ambient temperature of the environment where the heat pump system is located, and determining the minimum stable superheat according to the preset ambient temperature-minimum stable superheat curve.

[0117] The current ambient temperature of the environment where the heat pump system is located can be obtained by using a temperature sensor provided in the environment where the heat pump system is located. The temperature sensor can be a temperature sensor such as a platinum resistance, a thermocouple, a digital temperature sensor, etc., which is not limited here.

[0118] The ambient temperature - minimum stable superheat curve can be obtained in advance through theoretical analysis, experimental testing, and system characteristic calibration, and stored in advance in the control device that executes the control method of the heat pump system.

[0119] Using the current ambient temperature in the environment of the heat pump system, querying in the ambient temperature - minimum stable superheat curve can obtain the minimum stable superheat corresponding to the current ambient temperature.

[0120] S602. Obtain the difference between the gaseous refrigerant temperature at the outlet of the evaporator of the heat pump system and the refrigerant saturation temperature at the pressure at the outlet of the evaporator as the superheat.

[0121] The gaseous refrigerant temperature at the outlet of the evaporator of the heat pump system can be obtained by using a temperature sensor set at the outlet of the evaporator of the heat pump system. The temperature sensor can be a temperature sensor such as a platinum resistance, a thermocouple, a digital temperature sensor, etc., which is not limited here.

[0122] The pressure at the outlet of the evaporator of the heat pump system can be obtained by using a pressure sensor set at the outlet of the evaporator of the heat pump system. The pressure sensor can be a pressure sensor such as a pressure transmitter, a mechanical pressure gauge, etc., which is not limited here.

[0123] The saturation temperature of the refrigerant refers to the temperature when the refrigerant reaches the gas - liquid equilibrium state (i.e., the saturated state) at a certain specific pressure. According to the pressure at the outlet of the evaporator, the refrigerant saturation temperature at this pressure can be obtained.

[0124] Take the difference between the gaseous refrigerant temperature at the outlet of the evaporator of the heat pump system and the refrigerant saturation temperature at the pressure at the outlet of the evaporator as the superheat of the evaporator of the heat pump system.

[0125] S603. Take the difference between the minimum stable superheat and the superheat as the third input parameter.

[0126] The third input parameter here is to distinguish it from the first input parameter and the second input parameter of the first controller, and does not mean that the second controller also has the first input parameter and the second input parameter.

[0127] In some examples, take the difference between the minimum stable superheat and the superheat of the evaporator as Figure 5 the first input parameter of the second controller in

[0128] S604. Take the change rate of the difference between the minimum stable superheat and the superheat as the fourth input parameter.

[0129] The change rate of the difference between the minimum stable superheat and the superheat refers to the change speed of the difference between the minimum stable superheat and the superheat with time.

[0130] In some examples, the change rate of the difference between the minimum stable superheat degree and the superheat degree of the evaporator is used as Figure 5 the fourth input parameter of the second controller in

[0131] S605. Input the third input parameter and the fourth input parameter into the second controller, and control the opening degree of the electronic expansion valve according to the second output parameter of the second controller.

[0132] The second output parameter is used to represent the adjustment amount of the opening degree of the electronic expansion valve.

[0133] The second output parameter here is to distinguish it from the first output parameter of the first controller, and it does not mean that the second controller also has a first output parameter.

[0134] In some examples, input the third input parameter and the fourth input parameter into Figure 5 the second controller in

[0135] During the stable operation stage of the heat pump system, use the second controller based on the fuzzy control algorithm. According to the minimum stable superheat degree corresponding to the current ambient temperature of the environment where the heat pump system is located and the superheat degree of the evaporator of the heat pump system, accurately control the opening degree of the electronic expansion valve, which can make the superheat degree of the evaporator of the heat pump system approach the minimum stable superheat degree corresponding to the current ambient temperature of the environment where the heat pump system is located, extend the two-phase region in the evaporator, enable more refrigerants to participate in phase change heat absorption, improve the heating capacity of the refrigerant, reduce the power consumption of the compressor, and improve the energy efficiency ratio of the heat pump system.

[0136] In some exemplary embodiments, as Figure 7 shown, controlling the opening degree of the electronic expansion valve according to the first output parameter or the second output parameter includes:

[0137] S701. Input the first output parameter or the second output parameter into the electronic expansion valve driver.

[0138] The electronic expansion valve driver is an electronic control device for accurately controlling the opening degree of the electronic expansion valve, which can convert the first output parameter output by the first controller or the second output parameter output by the second controller into a pulse modulation signal for controlling the opening degree of the electronic expansion valve.

[0139] When controlling the opening degree of the electronic expansion valve using the first output parameter or the second output parameter, input the first output parameter or the second output parameter into the electronic expansion valve driver.

[0140] S702. Control the opening degree of the electronic expansion valve according to the third output parameter of the electronic expansion valve driver.

[0141] The third output parameter is a pulse modulation signal.

[0142] Control the opening degree of the electronic expansion valve according to the third output parameter in the form of a pulse modulation signal obtained by converting the first output parameter or the second output parameter by the electronic expansion valve driver.

[0143] Using the electronic expansion valve driver to convert the first output parameter of the first controller or the second output parameter of the second controller into a pulse modulation signal suitable for controlling the opening degree of the electronic expansion valve improves the control accuracy of the opening degree of the electronic expansion valve.

[0144] In this embodiment, during the startup process of the heat pump system, the first controller is used to control the opening degree of the electronic expansion valve according to the exhaust temperature set value and the exhaust temperature of the compressor of the heat pump system, which can effectively suppress the oscillation of the superheat degree of the evaporator, shorten the adjustment time, and improve the stability of the operation of the heat pump system. After the heat pump system enters the stable operation stage, the second controller is used to control the opening degree of the electronic expansion valve according to the minimum stable superheat degree corresponding to the current ambient temperature of the environment where the heat pump system is located and the superheat degree of the evaporator of the heat pump system, which can make the superheat degree of the evaporator of the heat pump system approach the minimum stable superheat degree, enable more refrigerant to participate in phase change heat absorption, improve the heating capacity of the refrigerant, reduce the power consumption of the compressor, and improve the energy efficiency ratio of the heat pump system.

[0145] An exemplary embodiment of the present application provides a control method for a heat pump system. As Figure 8 shown, the control method of the heat pump system shown in this exemplary embodiment includes:

[0146] S801. During the startup process of the heat pump system, obtain the initial water temperature when the heat pump system starts.

[0147] S802. Obtain the current water temperature of the heat pump system.

[0148] S803. Compare the difference between the current water temperature and the initial water temperature with a first preset value.

[0149] S804. In response to the difference between the current water temperature and the initial water temperature being greater than the first preset value, determine that the heat pump system enters the stable operation state.

[0150] S805. In response to the difference between the current water temperature and the initial water temperature being less than or equal to the first preset value, determine that the heat pump system has not entered the stable operation state.

[0151] S806. When the heat pump system does not enter the stable operation state, obtain the temperature at the exhaust port of the compressor of the heat pump system as the exhaust temperature.

[0152] S807. Take the difference between the exhaust temperature set value and the exhaust temperature as the first input parameter.

[0153] S808. Take the change rate of the difference between the exhaust temperature set value and the exhaust temperature as the second input parameter.

[0154] S809. Input the first input parameter and the second input parameter into the first controller, input the first output parameter of the first controller into the electronic expansion valve driver, and control the opening degree of the electronic expansion valve according to the third output parameter of the electronic expansion valve driver.

[0155] S810. When the heat pump system enters the stable operation state, use the current ambient temperature of the environment where the heat pump system is located, and determine the minimum stable superheat degree according to the preset ambient temperature - minimum stable superheat degree curve.

[0156] S811. Obtain the difference between the refrigerant gas temperature at the outlet of the evaporator of the heat pump system and the refrigerant saturation temperature at the pressure at the outlet of the evaporator as the superheat degree.

[0157] S812. Take the difference between the minimum stable superheat degree and the superheat degree as the third input parameter.

[0158] S813. Take the change rate of the difference between the minimum stable superheat degree and the superheat degree as the fourth input parameter.

[0159] S814. Input the third input parameter and the fourth input parameter into the second controller, input the second output parameter of the second controller into the electronic expansion valve driver, and control the opening degree of the electronic expansion valve according to the third output parameter of the electronic expansion valve driver.

[0160] Wherein, the exhaust temperature is negatively correlated with the opening degree of the electronic expansion valve, and the superheat degree is negatively correlated with the opening degree of the electronic expansion valve.

[0161] In this embodiment, during the startup process of the heat pump system, a first controller is used to control the opening degree of the electronic expansion valve according to the exhaust temperature set value and the exhaust temperature of the compressor of the heat pump system, which can effectively suppress the oscillation of the superheat degree of the evaporator, shorten the adjustment time, and improve the operating stability of the heat pump system. After the heat pump system enters the stable operation stage, a second controller is used to control the opening degree of the electronic expansion valve according to the minimum stable superheat degree corresponding to the current ambient temperature of the environment where the heat pump system is located and the superheat degree of the evaporator of the heat pump system, which can make the superheat degree of the evaporator of the heat pump system approach the minimum stable superheat degree, enable more refrigerant to participate in phase change heat absorption, enhance the heating capacity of the refrigerant, reduce the power consumption of the compressor, and improve the energy efficiency ratio of the heat pump system.

[0162] An exemplary embodiment of the present application provides a control device for a heat pump system, as Figure 9 shown. The control device of the heat pump system includes a startup stage control module 901, an operating state judgment module 902, and a stable operation stage control module 903.

[0163] The startup stage control module 901 is configured to control the opening degree of the electronic expansion valve using a first controller during the startup process of the heat pump system. The first controller controls the opening degree of the electronic expansion valve based on the exhaust temperature set value and the exhaust temperature of the compressor of the heat pump system.

[0164] The operating state judgment module 902 is configured to judge whether the heat pump system enters a stable operation state during the startup process of the heat pump system. The stable operation state refers to a state where the system parameters of the heat pump system reach dynamic equilibrium.

[0165] The stable operation stage control module 903 is configured to control the opening degree of the electronic expansion valve using a second controller in response to the heat pump system entering the stable operation state. The second controller controls the opening degree of the electronic expansion valve based on the minimum stable superheat degree corresponding to the current ambient temperature of the environment where the heat pump system is located and the superheat degree of the evaporator of the heat pump system.

[0166] In this embodiment, during the startup process of the heat pump system, a first controller is used to control the opening degree of the electronic expansion valve according to the exhaust temperature set value and the exhaust temperature of the compressor of the heat pump system, which can effectively suppress the oscillation of the superheat degree of the evaporator, shorten the adjustment time, and improve the operating stability of the heat pump system. After the heat pump system enters the stable operation stage, a second controller is used to control the opening degree of the electronic expansion valve according to the minimum stable superheat degree corresponding to the current ambient temperature of the environment where the heat pump system is located and the superheat degree of the evaporator of the heat pump system, which can make the superheat degree of the evaporator of the heat pump system approach the minimum stable superheat degree, enable more refrigerant to participate in phase change heat absorption, enhance the heating capacity of the refrigerant, reduce the power consumption of the compressor, and improve the energy efficiency ratio of the heat pump system.

[0167] In some exemplary embodiments, the operating state determination module 902 is further configured to:

[0168] Obtain the initial water temperature when the heat pump system starts;

[0169] Obtain the current water temperature of the heat pump system;

[0170] Compare the difference between the current water temperature and the initial water temperature with a first preset value;

[0171] In response to the difference between the current water temperature and the initial water temperature being greater than the first preset value, determine that the heat pump system enters a stable operating state;

[0172] In response to the difference between the current water temperature and the initial water temperature being less than or equal to the first preset value, determine that the heat pump system does not enter a stable operating state;

[0173] Wherein, both the initial water temperature and the current water temperature are the temperatures of the circulating water on the user side in the heat pump system.

[0174] In some exemplary embodiments, the startup phase control module 901 is further configured to:

[0175] Obtain the temperature at the exhaust port of the compressor of the heat pump system as the exhaust temperature;

[0176] Take the difference between the exhaust temperature set value and the exhaust temperature as the first input parameter;

[0177] Take the change rate of the difference between the exhaust temperature set value and the exhaust temperature as the second input parameter;

[0178] Input the first input parameter and the second input parameter into the first controller, and control the opening degree of the electronic expansion valve according to the first output parameter of the first controller, wherein the first output parameter is used to characterize the adjustment amount of the opening degree of the electronic expansion valve.

[0179] In some exemplary embodiments, the stable operation phase control module 903 is further configured to:

[0180] Obtain the minimum stable superheat;

[0181] Obtain the difference between the refrigerant gas temperature at the outlet of the evaporator of the heat pump system and the refrigerant saturation temperature at the pressure at the outlet of the evaporator as the superheat;

[0182] Take the difference between the minimum stable superheat and the superheat as the third input parameter;

[0183] Take the change rate of the difference between the minimum stable superheat and the superheat as the fourth input parameter;

[0184] Input the third input parameter and the fourth input parameter into the second controller, and control the opening degree of the electronic expansion valve according to the second output parameter of the second controller, where the second output parameter is used to characterize the adjustment amount of the opening degree of the electronic expansion valve.

[0185] In some exemplary embodiments, the stable operation stage control module 903 is further configured to:

[0186] Use the current ambient temperature of the heat pump system, and determine the minimum stable superheat degree according to the preset ambient temperature - minimum stable superheat degree curve.

[0187] In some exemplary embodiments, controlling the opening degree of the electronic expansion valve according to the first output parameter or the second output parameter includes:

[0188] Input the first output parameter or the second output parameter into the electronic expansion valve driver;

[0189] Control the opening degree of the electronic expansion valve according to the third output parameter of the electronic expansion valve driver;

[0190] Wherein, the third output parameter is a pulse modulation signal.

[0191] In some exemplary embodiments, the exhaust temperature is negatively correlated with the opening degree of the electronic expansion valve, and the superheat degree is negatively correlated with the opening degree of the electronic expansion valve.

[0192] Each module in the control device of the above heat pump system can be implemented in whole or in part by software, hardware and their combination. The above modules can be embedded in the processor in the computer device in the form of hardware or be independent of the processor, or can be stored in the memory in the computer device in the form of software, so as to facilitate the processor to call and execute the operations corresponding to the above respective modules.

[0193] An exemplary embodiment of the present application provides a computer device, including a processor and a memory, the memory stores a computer program, and when the processor executes the computer program, the steps of any one of the above heat pump system control methods are implemented.

[0194] An exemplary embodiment of the present application provides a non - temporary computer - readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of any one of the above heat pump system control methods are implemented. The computer - readable storage medium can be ROM, random access memory (RAM), CD - ROM, magnetic tape, floppy disk, and optical data storage device, etc.

[0195] An exemplary embodiment of the present application provides a computer program product, including a computer program, and when the computer program is executed by a processor, the steps of any one of the above heat pump system control methods are implemented.

[0196] ReferenceFigure 10 , a block diagram of a computer device that can be used in the present application will now be described. The computer device includes a computing unit 1001, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) 1002 or a computer program loaded from a storage unit 1008 into a random access memory (RAM) 1003. In the RAM 1003, various programs and data required for the operation of the computer device 1000 can also be stored. The computing unit 1001, the ROM 1002, and the RAM 1003 are connected to each other via a bus 1004. An input / output (I / O) interface 1005 is also connected to the bus 1004.

[0197] A plurality of components in the computer device 1000 are connected to the I / O interface 1005, including: an input unit 1006, an output unit 1007, a storage unit 1008, and a communication unit 1009. The input unit 1006 can be any type of device that can input information into the computer device 1000. The input unit 1006 can receive input digital or character information, and generate key signal inputs related to user settings and / or function controls of the computer device 1000, and can include but are not limited to a mouse, a keyboard, a touch screen, a trackpad, a trackball, a joystick, a microphone, and / or a remote control. The output unit 1007 can be any type of device that can present information, and can include but are not limited to a display, a speaker, a video / audio output terminal, a vibrator, and / or a printer. The storage unit 1008 can include but are not limited to a magnetic disk, an optical disk. The communication unit 1009 allows the computer device 1000 to exchange information / data with other devices via a computer network such as the Internet and / or various telecommunication networks, and can include but are not limited to a modem, a network card, an infrared communication device, a wireless communication transceiver, and / or a chipset, such as a BluetoothTM device, a WiFi device, a WiMax device, a cellular communication device, and / or the like.

[0198] The computing unit 1001 can be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the computing unit 1001 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The computing unit 1001 executes the various methods and processes described above, such as the control method of the heat pump system. For example, in some embodiments, the control method of the heat pump system can be implemented as a computer software program, which is tangibly included in a machine-readable medium, such as the storage unit 1008. In some embodiments, part or all of the computer program can be loaded and / or installed onto the computer device 1000 via the ROM 1002 and / or the communication unit 1009. When the computer program is loaded into the RAM 1003 and executed by the computing unit 1001, one or more steps of the control method of the heat pump system described above can be executed. Alternatively, in other embodiments, the computing unit 1001 can be configured to execute the control method of the heat pump system by any other suitable means (e.g., by means of firmware).

[0199] The computer device 1000 can be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components for executing the above-described control method of the heat pump system.

[0200] Those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include known common knowledge or conventional technical means in the technical field not disclosed in this application. The specification and embodiments are only to be considered exemplary, and the true scope and spirit of the present invention are pointed out by the following claims.

[0201] It should be understood that the present invention is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present invention is only limited by the appended claims.

Claims

1. A control method for a heat pump system, characterized in that: The heat pump system includes an electronic expansion valve, and the control method includes: During the startup of the heat pump system, the first controller is used to control the opening of the electronic expansion valve, and to determine whether the heat pump system enters a stable operation state, wherein the stable operation state refers to a state in which system parameters of the heat pump system reach a dynamic balance, and the first controller controls the opening of the electronic expansion valve based on an exhaust temperature setting value and an exhaust temperature of a compressor of the heat pump system; In response to the heat pump system entering the stable operating state, a second controller is used to control the opening of the electronic expansion valve, wherein the second controller controls the opening of the electronic expansion valve based on a minimum stable superheat corresponding to a current ambient temperature of the environment in which the heat pump system is located and a superheat of an evaporator of the heat pump system.

2. The control method of the heat pump system according to claim 1, characterized in that: The determining whether the heat pump system has entered a stable operation state comprises: Obtaining the initial water temperature when the heat pump system is started; Obtaining the current water temperature of the heat pump system; Comparing the difference between the current water temperature and the initial water temperature with a first preset value; In response to a difference between the current water temperature and the initial water temperature being greater than the first preset value, determining that the heat pump system enters the stable operation state; In response to a difference between the current water temperature and the initial water temperature being less than or equal to the first preset value, determining that the heat pump system has not entered the stable operating state; The initial water temperature and the current water temperature are both the temperatures of circulating water on the user side of the heat pump system.

3. The control method of the heat pump system according to claim 1, characterized in that: The using the first controller to control the opening of the electronic expansion valve comprises: Acquiring the temperature at the exhaust port of the compressor of the heat pump system as the exhaust temperature; taking the difference between the exhaust temperature setting value and the exhaust temperature as a first input parameter; taking the rate of change of the difference between the exhaust temperature setting value and the exhaust temperature as a second input parameter; The first input parameter and the second input parameter are input into the first controller, and the opening of the electronic expansion valve is controlled according to a first output parameter of the first controller, wherein the first output parameter is used to characterize the adjustment amount of the opening of the electronic expansion valve.

4. The control method of the heat pump system according to claim 1, characterized in that: The using the second controller to control the opening of the electronic expansion valve comprises: Obtaining the minimum stable superheat; obtaining a difference between a gaseous temperature of the refrigerant at an outlet of the evaporator of the heat pump system and a saturated temperature of the refrigerant under a pressure at an outlet of the evaporator as the superheat degree; taking the difference between the minimum stable superheat and the superheat as a third input parameter; taking the rate of change of the difference between the minimum stable superheat and the superheat as a fourth input parameter; The third input parameter and the fourth input parameter are input into the second controller, and the opening of the electronic expansion valve is controlled according to a second output parameter of the second controller, wherein the second output parameter is used to characterize the adjustment amount of the opening of the electronic expansion valve.

5. The control method of the heat pump system according to claim 4, characterized in that: The obtaining of the minimum stable superheat comprises: The minimum stable superheat is determined by using the current ambient temperature of the environment in which the heat pump system is located and according to a preset ambient temperature-minimum stable superheat curve.

6. The control method of the heat pump system according to claim 3 or 4, characterized in that: Controlling the opening of the electronic expansion valve according to the first output parameter or the second output parameter includes: inputting the first output parameter or the second output parameter to an electronic expansion valve driver; controlling the opening of the electronic expansion valve according to a third output parameter of the electronic expansion valve driver; Wherein, the third output parameter is a pulse modulation signal.

7. The control method of the heat pump system according to claim 1, characterized in that: The exhaust temperature is negatively correlated with the opening degree of the electronic expansion valve, and the superheat is negatively correlated with the opening degree of the electronic expansion valve.

8. A control device for a heat pump system, characterized in that: The heat pump system includes an electronic expansion valve, and the control device includes: a startup phase control module, configured to control the opening of the electronic expansion valve using a first controller during the startup of the heat pump system, wherein the first controller controls the opening of the electronic expansion valve based on an exhaust temperature set value and an exhaust temperature of a compressor of the heat pump system; an operation state judgment module, configured to judge whether the heat pump system enters a stable operation state during the startup process of the heat pump system, wherein the stable operation state refers to a state in which system parameters of the heat pump system reach a dynamic balance; The stable operation phase control module is configured to control the opening of the electronic expansion valve using a second controller in response to the heat pump system entering the stable operation state, wherein the second controller controls the opening of the electronic expansion valve based on a minimum stable superheat corresponding to a current ambient temperature of an environment in which the heat pump system is located and a superheat of an evaporator of the heat pump system.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method for controlling the heat pump system according to any one of claims 1 to 7 are implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the control method of the heat pump system according to any one of claims 1 to 7 are implemented.

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