CN111878964B - Control method and device of electronic expansion valve, air conditioner and storage medium - Google Patents

Abstract

The invention provides a control method, device, air conditioner and storage medium of an electronic expansion valve. The control method includes: acquiring indoor temperature, indoor set temperature, subcooling degree or superheating degree, target subcooling degree or target superheating degree; adopting a fuzzy control method to obtain the opening degree adjustment value of the electronic expansion valve, and adjusting according to the opening degree value to adjust the electronic expansion valve. The present invention corrects the valve step size of the electronic expansion valve during the heating or cooling process of the air conditioner through the combined control based on the degree of subcooling or the degree of superheat and the room temperature, and on the basis of the degree of subcooling/superheating degree control, thereby obtaining more The opening degree of the electronic expansion valve suitable for the current state improves the control accuracy of the electronic expansion valve, as well as the adaptability to different conditions, and effectively improves the heat exchange efficiency and system stability of the air conditioner.

Description

An electronic expansion valve control method, device, air conditioner and storage medium

technical field

The present invention relates to the technical field of air conditioners, and in particular, to a control method and device of an electronic expansion valve, an air conditioner and a storage medium.

Background technique

The current air conditioning heat exchange system mostly uses electronic expansion valve to control and adjust the refrigerant flow rate, thereby improving the heat conversion efficiency of the refrigerant and ensuring that the heat exchange system can consume the least energy and provide the best heat exchange effect. At present, the commonly used expansion valve adjustment methods are mostly based on the degree of superheat or subcooling to periodically control the expansion valve, but the control method only based on the degree of superheat or subcooling has poor adaptability, weak adjustment ability, and often poor heat exchange. , conditions that affect comfort.

SUMMARY OF THE INVENTION

The problem solved by the present invention is that the current method of periodically controlling the electronic expansion valve only based on the degree of superheat or the degree of subcooling has poor adaptability and limited adjustment capability.

In order to solve the above problems, the present invention provides a control method of an electronic expansion valve, including:

Get indoor temperature, indoor set temperature, subcooling or superheating, target subcooling or target superheating;

According to the indoor temperature, the rate of change of the indoor temperature and the indoor set temperature, the first pre-adjustment value of the opening degree is obtained by using the first fuzzy control model, and according to the degree of superheat, the rate of change of the degree of superheat and the target degree of superheat or according to the degree of subcooling, the rate of change of the degree of subcooling, and the target degree of subcooling, using a second fuzzy control model to obtain a second opening degree pre-adjustment value;

According to the range of the degree of superheat or the degree of subcooling, the opening degree adjustment value of the electronic expansion valve is obtained by superimposing control on the first opening degree pre-adjustment value and the second opening degree pre-adjustment value , and adjust the electronic expansion valve according to the opening adjustment value.

The present invention corrects the valve step size of the electronic expansion valve during the heating or cooling process of the air conditioner through the combined control based on the degree of subcooling or the degree of superheat and the room temperature, and on the basis of the degree of subcooling/superheating degree control, and corrects the valve step size of the electronic expansion valve during the heating or cooling process of the air conditioner. In the case of subcooling/superheating control and room temperature control, variables that reflect the changing trend of parameters such as the rate of change of the corresponding parameters (superheat or subcooling, indoor temperature) are involved in the calculation to obtain output variables that better match the current parameters The pre-adjustment value of the opening degree of the electronic expansion valve, and then the supercooling or superheating degree control and the output variable of the room temperature control are superimposed, so as to obtain the opening degree of the electronic expansion valve more suitable for the current state, improve the control accuracy of the electronic expansion valve, and Adaptability to different conditions, effectively improve the heat exchange efficiency and system stability of the air conditioner.

Further, the first fuzzy control model is:

ΔPP ₁ =UV(t);

R(t)为所述室内设定温度，ω为控制速度决定因数，ζ为阻尼系数，B为控制临界值；Among them, ΔPP ₁ is the first opening degree pre-adjustment value, UV(t) is the opening degree of the electronic expansion valve output by the room temperature control, UV(tL) is the opening degree of the electronic expansion valve in the previous cycle, and L is Control cycle, Y ₁ (t) is the indoor temperature, Y ₁ (tL) is the indoor temperature of the previous cycle,

R(t) is the indoor set temperature, ω is the control speed determining factor, ζ is the damping coefficient, and B is the control critical value;

The second fuzzy control model is:

ΔPP ₂ =USC(t);

R(t)为所述目标过热度或所述目标过冷度，ω为控制速度决定因数，ζ为阻尼系数，B为控制临界值。Among them, ΔPP ₂ is the second opening degree pre-adjustment value, USC(t) is the opening degree of the electronic expansion valve output by the superheat degree control or subcool degree control, and USC(tL) is the electronic expansion valve in the previous cycle The opening degree of , L is the control period, Y ₂ (t) is the degree of superheat or the degree of subcooling, Y ₂ (tL) is the degree of superheat or subcooling in the previous cycle,

R(t) is the target degree of superheat or the target degree of subcooling, ω is a control speed determining factor, ζ is a damping coefficient, and B is a control critical value.

In this way, it can be ensured that the calculated opening degree of the expansion valve is reasonable and meets the current environmental requirements, has higher real-time performance, and can respond in time according to environmental changes.

Further, obtaining the opening degree adjustment value of the electronic expansion valve by superimposing control on the first opening degree pre-adjustment value and the second opening degree pre-adjustment value includes: performing the first opening degree pre-adjustment according to the following formula The superposition of the value and the second opening degree pre-adjustment value to obtain the opening degree adjustment value ΔP:

ΔP=f ₁ (x)×ΔPP ₁ +f ₂ (x)×ΔPP ₂ ;

Wherein, ΔPP ₁ is the first opening degree pre-adjustment value, ΔPP ₂ is the second opening degree pre-adjustment value, f ₁ (x) is the first membership function, f ₂ (x) is the second membership function, And f ₁ (x) and f ₂ (x) satisfy the following relationship:

f ₁ (x)+f ₂ (x)=1.

Under the premise of ensuring the safety of superheat or subcooling, the present invention participates in room temperature control, switches subcooling/superheating control and room temperature control through fuzzy control, effectively adjusts unit capacity output, and has strong scene adaptability.

Further, the first membership function or the second membership function includes one of a triangular membership function, a trapezoidal membership function and a generalized bell membership function.

Further, the first membership function is:

Wherein, x is the degree of superheat or the degree of subcooling, and a, b, c, and d are different set values.

In this way, when the degree of superheat or subcooling is in a too large or too small range, the control based on the degree of superheat or subcooling is adopted to ensure the reliability of the system, and when the degree of superheat or subcooling is in a large or small range When the supercooling degree/superheating degree control and the room temperature control are combined control, when the superheating degree or the subcooling degree is in the middle range, the indoor temperature-based control is adopted, and the present invention can realize the subcooling degree/superheating degree control and the room temperature control Switch between, improve the adjustment ability and adaptability to different situations.

Further, when x is the degree of supercooling, the value of a is 3-9°C, the value of b is 8-14°C, the value of c is 22-28°C, and the value of d is 27- 33°C.

Further, after acquiring the opening adjustment value of the electronic expansion valve, the method further includes: correcting the opening adjustment value, and the correction rule is:

When the degree of subcooling is less than the set value of the degree of subcooling, the corrected opening degree adjustment value is equal to the opening degree adjustment value minus the first correction value;

When the subcooling degree is greater than or equal to the first preset value, determine whether the temperature difference is greater than the temperature difference set value, wherein the temperature difference is the difference between the indoor temperature and the indoor set temperature;

When the temperature difference is greater than the temperature difference set value, the corrected opening adjustment value is equal to the opening adjustment value plus a second correction value;

When the temperature difference is less than or equal to the temperature difference setting value, the corrected opening degree adjustment value is equal to the opening degree adjustment value.

By revising the opening adjustment value, the opening adjustment value of the electronic expansion valve that is more suitable for the current state is obtained, thereby improving the heat exchange efficiency and improving the user's comfort.

Further, the set value of the subcooling degree is 5°C, the first correction value is 12, the set value of the temperature difference is 1°C, and the second correction value is 5.

In the heating mode, the present invention obtains the opening adjustment value of the electronic expansion valve based on the combined control of the subcooling degree control and the room temperature control, and corrects the valve opening degree when the subcooling degree is less than 5°C. When the temperature difference is in the normal range, the temperature difference is judged. When the temperature difference is large and exceeds 1°C, the valve opening is also corrected, so that the adjustment amount of the electronic expansion valve opening that is more suitable for the current situation is obtained.

The present invention also provides a control device for an electronic expansion valve, comprising:

an acquisition unit, the acquisition unit is configured to acquire indoor temperature, indoor set temperature, degree of subcooling or degree of superheat, target degree of subcooling or target degree of superheat;

a control unit, the control unit is configured to use a first fuzzy control model to obtain a first opening degree pre-adjustment value according to the indoor temperature, the rate of change of the indoor temperature and the indoor set temperature, and according to the superheat degree , the rate of change of the degree of superheat and the target degree of superheat, or according to the degree of subcooling, the rate of change of the degree of subcooling and the target degree of subcooling, use the second fuzzy control model to obtain a second opening degree prediction adjustment value;

The control unit is further configured to perform superposition control on the first opening degree pre-adjustment value and the second opening degree pre-adjustment value according to the range of the degree of superheat or the degree of subcooling, and obtain the electronic The opening adjustment value of the expansion valve.

The present invention also provides an air conditioner, comprising a computer-readable storage medium storing a computer program and a processor, and when the computer program is read and executed by the processor, the above-mentioned control method for an electronic expansion valve is implemented .

The present invention also provides a computer-readable storage medium, where a computer program is stored in the computer-readable storage medium, and when the computer program is read and executed by a processor, the above-mentioned control method of an electronic expansion valve is implemented.

Compared with the prior art, the electronic expansion valve control device and the air conditioner provided by the present invention have the same beneficial effects as the electronic expansion valve control method, which will not be repeated here.

Description of drawings

1 is a flowchart of a control method of an electronic expansion valve in an embodiment of the present invention;

FIG. 2 is a specific control flow chart of the electronic expansion valve in the embodiment of the present invention.

Detailed ways

In order to make the above objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Referring to FIG. 1, an embodiment of the present invention provides a control method for an electronic expansion valve, including:

Obtain the indoor temperature, indoor set temperature, subcooling or superheating, target subcooling or target superheating; it should be understood that in the heating mode, the subcooling and target subcooling are obtained, and in the cooling mode , the obtained superheat and target superheat;

According to the indoor temperature, the rate of change of the indoor temperature and the indoor set temperature, use the first fuzzy control model to obtain the first pre-adjustment value of the opening degree, and according to the degree of superheat, the rate of change of the degree of superheat and the target degree of superheat or according to the degree of supercooling, The rate of change of the subcooling degree and the target subcooling degree, and the second opening degree pre-adjustment value is obtained by using the second fuzzy control model;

According to the range of the degree of superheat or the degree of subcooling, the superposition control of the first opening pre-adjustment value and the second opening degree pre-adjustment value is performed to obtain the opening degree adjustment value of the electronic expansion valve, and the electronic expansion valve is adjusted according to the opening degree adjustment value. Adjust the expansion valve.

In this embodiment, the indoor temperature, the rate of change of the indoor temperature, and the indoor set temperature are input to the first controller, and the first controller is used to perform control based on the indoor temperature, which is hereinafter referred to as room temperature control for ease of description. In cooling mode, input the degree of superheat, the rate of change of superheat and the target degree of superheat into the second controller, and use the second controller to perform control based on degree of superheat, or in heating mode, input the degree of supercooling, the rate of change of subcooling degree and the target subcooling degree are input to the second controller, and the second controller is used to perform control based on the degree of subcooling, and the control based on the degree of superheat or the degree of subcooling is simply referred to as degree of supercooling/degree of superheating control. The so-called control based on degree of superheat or degree of subcooling takes the degree of superheat or subcooling as the input variable, and through the calculation of the controller, the amount of change in the opening degree of the electronic expansion valve is output, so as to control the opening degree of the electronic expansion valve. The so-called indoor temperature-based control takes the indoor temperature as the input variable, and outputs the change in the opening degree of the electronic expansion valve through the calculation of the controller, thereby controlling the opening degree of the electronic expansion valve. In this embodiment, both the first controller and the second controller adopt the fuzzy PID control method, wherein the first controller outputs the first opening degree pre-adjustment value, and the second controller outputs the second opening degree pre-adjustment value. And according to the degree of superheat or the range of the degree of superheat, the electronic expansion valve is controlled by the fuzzy control method to control the degree of subcooling/superheat and the control of the room temperature. The superposition of , obtains the opening adjustment value, and then adjusts the electronic expansion valve.

This embodiment is different from the defects in the prior art, such as poor adaptability and limited adjustment capability, which are caused by single control only by the degree of subcooling or degree of superheat. On the basis of superheat control, fuzzy control is used to correct the valve step size of the electronic expansion valve in the heating or cooling process of the air conditioner, so as to obtain the opening degree of the electronic expansion valve more suitable for the current state, improve the control accuracy of the electronic expansion valve, and improve the control accuracy of the electronic expansion valve. The adaptability to different conditions can effectively improve the heat exchange efficiency and system stability of the air conditioner.

Further, the first opening degree pre-adjustment value ΔPP ₁ is calculated by adopting the first fuzzy control model:

ΔPP ₁ =UV(t);

YDD₁(t)为两个室内温度变化率的变化率，

Among them, UV(t) is the opening degree of the electronic expansion valve output by the room temperature control, UV(tL) is the opening degree of the electronic expansion valve in the previous cycle, L is the control period, Y ₁ (t) is the indoor temperature, and Y ₁ (tL) is The indoor temperature of the previous cycle, R(t) is the indoor set temperature, ω is the control speed determining factor, ζ is the damping coefficient, B is the control critical value, and YD ₁ (t) is the indoor temperature of two adjacent control cycles rate of change,

YDD ₁ (t) is the change rate of the two indoor temperature change rates,

The second opening degree pre-adjustment value ΔPP ₂ is calculated by using the second fuzzy control model:

ΔPP ₂ =USC(t);

YDD₂(t)为两个过热度变化率的变化率或者两个过冷度变化率的变化率，

Among them, USC(t) is the opening degree of the electronic expansion valve controlled by the superheat degree or subcooling degree, USC(tL) is the opening degree of the electronic expansion valve in the previous cycle, L is the control period, and Y ₂ (t) is the degree of superheat or subcooling degree, Y ₂ (tL) is the superheating degree or subcooling degree of the previous cycle, R(t) is the target superheating degree or target subcooling degree, ω is the control speed determining factor, ζ is the damping coefficient, and B is the Control critical value, YD ₂ (t) is the rate of change of superheat or the rate of change of subcooling in two adjacent control cycles,

YDD ₂ (t) is the change rate of the two superheat degree change rates or the change rate of the two subcool degree change rates,

In this embodiment, the first opening degree pre-adjustment value and the second opening degree pre-adjustment value are respectively calculated by the first fuzzy control model and the second fuzzy control model as above, which can ensure that the calculated opening degree of the expansion valve is reasonable and meets the current environmental requirements. , the real-time performance is higher, and it can respond in time according to environmental changes.

Further, according to the first opening degree pre-adjustment value and the second opening degree pre-adjustment value, the fuzzy control method is used to superimpose the first opening degree pre-adjustment value and the second opening degree pre-adjustment value to obtain the electronic expansion valve. Opening adjustment value, including:

The membership function is determined based on the following control principles:

When the degree of superheat or the degree of subcooling is less than or equal to the third preset value or greater than or equal to the sixth preset value, the second controller is used to control the opening degree of the electronic expansion valve;

When the degree of superheat or subcooling is greater than the third preset value and less than the fourth preset value or the degree of superheat or subcooling is greater than the fifth preset value and less than the sixth preset value, the first controller and the second The controller jointly controls the opening of the electronic expansion valve;

When the degree of superheat or the degree of subcooling is greater than or equal to the fourth preset value and less than or equal to the fifth preset value, use the first controller to control the opening degree of the electronic expansion valve;

The third preset value is smaller than the fourth preset value, the fourth preset value is smaller than the fifth preset value, and the fifth preset value is smaller than the sixth preset value.

In this embodiment, when the degree of superheat or subcooling is too large or too small, the degree of supercooling/superheating degree control is used, when the degree of superheating or subcooling is in a moderate range, the room temperature control is used, and in other cases, both are used. Therefore, the system reliability is guaranteed, and the adaptability is stronger, and it can respond in time to the valve step requirements in various situations.

The membership functions include a first membership function f ₁ (x) and a second membership function f ₂ (x), and f ₁ (x)+f ₂ (x)=1. f ₁ (x) includes one of a triangular membership function, a trapezoidal membership function and a generalized bell-shaped membership function, and f ₂ (x) is obtained according to f ₁ (x)+f ₂ (x)=1. Or f ₂ (x) includes one of a triangular membership function, a trapezoidal membership function, and a generalized bell-shaped membership function, and f 1 (x) is derived from f ₁ (x)+f ₂ (x)= ₁ .

After determining the membership function, calculate the opening adjustment value ΔP of the electronic expansion valve according to the following formula;

ΔP=f ₁ (x)×ΔPP ₁ +f ₂ (x)×ΔPP ₂ ;

Wherein, ΔPP ₁ is the first opening degree pre-adjustment value, and ΔPP ₂ is the second opening degree pre-adjustment value;

Preferably, the membership function f ₁ (x) is:

Among them, x is the degree of superheat or subcooling, and a, b, c, and d are different set values.

Further, in order to ensure that the adjustment value of the opening degree of the electronic expansion valve obtained by the above calculation can adapt to the current situation, better improve the heat exchange efficiency, and improve the comfort of the user, in this embodiment, after obtaining the adjustment value of the opening degree of the electronic expansion valve, It also includes: correcting the opening adjustment value.

The correction rules are:

When the degree of subcooling is less than the set value of the degree of subcooling, the corrected opening adjustment value is equal to the opening adjustment value minus the first correction value;

When the degree of subcooling is greater than or equal to the first preset value, determine whether the temperature difference is greater than the set value of the temperature difference, wherein the temperature difference is the difference between the indoor temperature and the indoor set temperature;

When the temperature difference is greater than the set value of the temperature difference, the corrected opening adjustment value is equal to the opening adjustment value plus the second correction value;

When the temperature difference is less than or equal to the set value of the temperature difference, the corrected opening adjustment value is equal to the opening adjustment value.

In the experimental study, it is found that when the subcooling degree is less than 5°C, the adjustment based on the opening degree of the electronic expansion valve based on the current opening degree of the electronic expansion valve has little effect. The correction value can be improved, so in this embodiment, when the set value of the degree of supercooling is set to 5°C, the first correction value is 12. Correspondingly, when the temperature difference is too large, the adjustment will also be affected. In this embodiment, the set value of the temperature difference is preferably 1°C, and the second correction value is preferably 5.

The present invention will be described in detail below with reference to specific embodiments. Take the control of the electronic expansion valve of the multi-connected internal unit in the heating mode as an example.

The control flow is shown in Figure 2. After the initialization control of the electronic expansion valve is completed, the heating internal unit enters the fuzzy control. The sensor detects the saturation temperature corresponding to the high pressure pressure, the temperature of the indoor unit inlet pipe and the indoor temperature, and calculates the subcooling degree according to T _{subcooling degree} = T _{corresponding saturation temperature of the high pressure pressure -} T _{indoor unit inlet pipe temperature} , and obtains the current indoor temperature, Indoor set temperature and target subcooling.

Calculate the first opening pre-adjustment value and the second opening degree pre-adjustment value respectively through the control models of room temperature control and subcooling degree control,

的取值为2000，ζ的取值为1，ω的取值为0.025。In the control model for calculating the first opening pre-adjustment value,

The value of is 2000, the value of ζ is 1, and the value of ω is 0.025.

的取值为-500，ζ的取值为1，ω的取值为0.05，目标过冷度R(t)的取值为8。In the control model for calculating the second opening pre-adjustment value,

The value of ζ is -500, the value of ζ is 1, the value of ω is 0.05, and the value of target subcooling degree R(t) is 8.

After calculating the first opening degree pre-adjustment value and the second opening degree pre-adjustment value, the trapezoidal membership function is used to calculate the opening degree adjustment value ΔP according to the following control model.

ΔP=f ₁ (x)×ΔPP ₁ +f ₂ (x)×ΔPP ₂ ;

in,

Preferably, the value of a is 6°C, the value of b is 11°C, the value of c is 25°C, and the value of d is 30°C.

According to the range of the subcooling degree, the specific calculation method for calculating the opening adjustment value is shown in Table 1.

Table 1:

After the opening adjustment value ΔP is calculated, the corrected opening adjustment value ΔP ^* is calculated according to the correction rule.

When the subcooling degree is less than 5℃, ΔP ^* =ΔP-12;

When the degree of subcooling is greater than or equal to 5°C and the temperature difference is greater than 1°C, ΔP ^* =ΔP+5;

When the subcooling degree is greater than or equal to 5°C and the temperature difference is less than or equal to 1°C, the adjustment value of the opening degree does not need to be corrected, that is, ΔP ^* =ΔP;

Finally, the electronic expansion valve is adjusted according to the corrected opening degree adjustment value, and the opening degree P of the electronic expansion valve is controlled to be: P= _Pcurrent +ΔP ^* .

An embodiment of the present invention also provides an electronic expansion valve control device, including:

an acquisition unit, which is used to acquire the indoor temperature, the indoor set temperature, the degree of subcooling or superheat, and the target degree of subcooling or target superheat;

A control unit, the control unit is configured to obtain the first opening degree pre-adjustment value by using the first fuzzy control model according to the indoor temperature, the rate of change of the indoor temperature and the indoor set temperature, according to the degree of superheat, the rate of change of the degree of superheat and the target degree of superheat Or according to the subcooling degree, the rate of change of the subcooling degree and the target subcooling degree, use the second fuzzy control model to obtain the second opening degree pre-adjustment value;

The control unit is further configured to perform superposition control on the first opening degree pre-adjustment value and the second opening degree pre-adjustment value according to the range of the degree of superheat or the degree of subcooling, so as to obtain the opening degree adjustment value of the electronic expansion valve.

Embodiments of the present invention further provide a computer-readable storage medium, where a computer program is stored in the computer-readable storage medium, and when the computer program is read and executed by a processor, a method for controlling an electronic expansion valve is implemented.

Although the present invention is disclosed above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be based on the scope defined by the claims.

Claims (10)

1. A control method of an electronic expansion valve, comprising:

acquiring indoor temperature, indoor set temperature, supercooling degree or superheat degree, target supercooling degree or target superheat degree;

acquiring a first opening pre-adjustment value by using a first fuzzy control model according to the indoor temperature, the change rate of the indoor temperature and the indoor set temperature, and acquiring a second opening pre-adjustment value by using a second fuzzy control model according to the superheat degree, the change rate of the superheat degree and the target superheat degree or according to the supercooling degree, the change rate of the supercooling degree and the target supercooling degree; acquiring an opening degree adjusting value of the electronic expansion valve through the superposition control of the first opening degree pre-adjusting value and the second opening degree pre-adjusting value according to the superheat degree or the range of the supercooling degree, and adjusting the electronic expansion valve according to the opening degree adjusting value;

wherein the acquiring the opening degree adjustment value of the electronic expansion valve by the superposition control of the first opening degree pre-adjustment value and the second opening degree pre-adjustment value comprises:

superposing the first opening pre-adjustment value and the second opening pre-adjustment value according to the following formula to obtain the opening adjustment value delta P:

ΔP＝f₁(x)×ΔPP₁+f₂(x)×ΔPP₂；

wherein, Δ PP₁For said first opening pre-adjustment value, Δ PP₂Is said second opening degree preset value, f₁(x) Is a first membership function, f₂(x) Is a second membership function, and f₁(x) And f₂(x) The following relationship is satisfied:

f₁(x)+f₂(x)＝1。

2. the control method of an electronic expansion valve according to claim 1, wherein the first fuzzy control model is:

ΔPP₁＝UV(t)；

wherein, Δ PP₁For the first opening degree pre-adjustment value, UV (t) is the opening degree of the electronic expansion valve of the room temperature control output, UV (t-L) is the opening degree of the electronic expansion valve in the previous period, L is the control period, Y is the opening degree of the electronic expansion valve in the previous period₁(t) is the room temperature, Y₁(t-L) is the room temperature of the previous cycle,

r (t) is the indoor set temperature, omega is a control speed determining factor, zeta is a damping coefficient, and B is a control critical value;

the second fuzzy control model is as follows:

ΔPP₂＝USC(t)；

wherein, Δ PP₂For the second opening degree preset value, USC (t) is the opening degree of the electronic expansion valve output by superheat degree control or supercooling degree control, USC (t-L) is the opening degree of the electronic expansion valve in the previous period, L is the control period, Y is the opening degree of the electronic expansion valve in the previous period₂(t) is the degree of superheat or theDegree of supercooling, Y₂(t-L) is the degree of superheat or supercooling of the previous cycle,

r (t) is the target superheat degree or the target supercooling degree, omega is a control speed determining factor, zeta is a damping coefficient, and B is a control critical value.

3. The control method of an electronic expansion valve according to claim 1 or 2, wherein the first or second membership function comprises one of a triangular membership function, a trapezoidal membership function and a generalized bell membership function.

4. The control method of an electronic expansion valve according to claim 1 or 2, characterized in that the first membership function is:

wherein x is the superheat degree or the supercooling degree, and a, b, c and d are different set values.

5. The control method of the electronic expansion valve according to claim 4, wherein when x is the supercooling degree, a is 3-9 ℃, b is 8-14 ℃, c is 22-28 ℃ and d is 27-33 ℃.

6. The control method of an electronic expansion valve according to claim 1 or 2, further comprising, after obtaining the opening degree adjustment value of the electronic expansion valve:

and correcting the opening degree adjusting value according to the following correction rule:

when the supercooling degree is smaller than the supercooling degree set value, the corrected opening degree adjusting value is equal to the opening degree adjusting value minus a first correction value;

when the supercooling degree is greater than or equal to a first preset value, judging whether the temperature difference is greater than a temperature difference set value, wherein the temperature difference is the difference between the indoor temperature and the indoor set temperature;

when the temperature difference is larger than the temperature difference set value, the corrected opening degree adjusting value is equal to the opening degree adjusting value plus a second correction value;

and when the temperature difference is smaller than or equal to the temperature difference set value, the corrected opening degree adjusting value is equal to the opening degree adjusting value.

7. The control method of the electronic expansion valve according to claim 6, wherein the supercooling degree set value is 5 ℃, the first correction value is 12, the temperature difference set value is 1 ℃, and the second correction value is 5.

8. A control device for an electronic expansion valve, comprising:

the system comprises an acquisition unit, a control unit and a control unit, wherein the acquisition unit is used for acquiring indoor temperature, indoor set temperature, supercooling degree or superheat degree, target supercooling degree or target superheat degree;

the control unit is used for acquiring a first preset opening value by using a first fuzzy control model according to the indoor temperature, the change rate of the indoor temperature and the indoor set temperature, and acquiring a second preset opening value by using a second fuzzy control model according to the superheat degree, the change rate of the superheat degree and the target superheat degree or according to the supercooling degree, the change rate of the supercooling degree and the target supercooling degree;

the control unit is also used for carrying out superposition control on the first opening degree pre-regulation value and the second opening degree pre-regulation value according to the range of the superheat degree or the supercooling degree to obtain an opening degree regulation value of the electronic expansion valve;

the overlapping control of the first opening degree pre-adjustment value and the second opening degree pre-adjustment value to obtain the opening degree adjustment value of the electronic expansion valve includes:

superposing the first opening pre-adjustment value and the second opening pre-adjustment value according to the following formula to obtain the opening adjustment value delta P:

ΔP＝f₁(x)×ΔPP₁+f₂(x)×ΔPP₂；

wherein, Δ PP₁For said first opening pre-adjustment value, Δ PP₂Is said second opening degree preset value, f₁(x) Is a first membership function, f₂(x) Is a second membership function, and f₁(x) And f₂(x) The following relationship is satisfied:

f₁(x)+f₂(x)＝1。

9. an air conditioner comprising a computer readable storage medium storing a computer program and a processor, the computer program being read and executed by the processor to implement a control method of an electronic expansion valve according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that it stores a computer program which, when read and executed by a processor, implements a control method of an electronic expansion valve according to any one of claims 1 to 7.

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