CN111486563A

CN111486563A - Control method and device of electronic expansion valve

Info

Publication number: CN111486563A
Application number: CN202010357160.7A
Authority: CN
Inventors: 徐春峰; 李达君; 常骞
Original assignee: Hisense Shandong Air Conditioning Co Ltd
Current assignee: Hisense Shandong Air Conditioning Co Ltd
Priority date: 2020-04-29
Filing date: 2020-04-29
Publication date: 2020-08-04
Anticipated expiration: 2040-04-29
Also published as: CN111486563B

Abstract

A control method and a control device for an electronic expansion valve and an air conditioner relate to the technical field of air conditioners and can solve the problem that the period of the electronic expansion valve of the air conditioner is not reasonable enough in an ultralow-temperature environment. The method comprises the following steps: acquiring the outdoor environment temperature; if the outdoor environment temperature is lower than the preset temperature value, entering an ultralow temperature heating operation mode, closing the electronic expansion valve, and enabling the electronic expansion valve to be in a closed state within a first preset time; determining a DSH difference value of the air conditioning system; the DSH difference is the actual DSH value minus the target DSH value; setting an electronic expansion valve adjusting period according to the DSH difference; and adjusting the opening degree of the electronic expansion valve according to the adjustment period of the electronic expansion valve. The method is used for the air conditioner.

Description

Control method and device of electronic expansion valve

Technical Field

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

Background

The inverter air conditioner is a conventional air conditioner additionally provided with an inverter, and the basic structure and the refrigeration principle of the inverter air conditioner are completely the same as those of a common air conditioner. The compressor is the core of the air conditioner, and the rotating speed of the compressor directly influences the use efficiency of the air conditioner. The inverter air conditioner controls and adjusts the rotating speed of the compressor through the inverter, so that the rotating speed of the compressor is always in the optimal rotating speed state, the energy efficiency ratio is improved, and the effect of being more stable than that of a common air conditioner is achieved.

Under the ultralow temperature environment, the heating requirement of the variable frequency air conditioner is in the maximum state, and the rotating speeds of the compressor and the fan are both freely controlled to be the maximum rotating speed at the moment. In order to prevent the superheat degree of the press from failing for a long time due to too low cold start low pressure, an Electronic Expansion Valve (EEV) is usually forcibly increased to increase the refrigerant flow so as to reach a set value of a discharge superheat Degree (DSH), and then normal DSH control is resumed.

After the ultra-low temperature heating starting stage is exited, the actual DSH value is low, EEV adjustment starts from a small opening degree, and the opening degree needs to be gradually increased. The prior art generally adopts a fixed valve adjusting mode once per minute, and the opening degree of the valve adjusting mode is increased or decreased according to a fixed period. However, the above method may have a problem of not being suitable for the actual operation condition of the air conditioner in the actual operation. For example, in an ultralow temperature environment, the power wave band is large due to the overlong adjusting time in the starting process, the temperature fluctuation of the air outlet is obvious, and the comfort of a user is reduced.

Disclosure of Invention

The embodiment of the invention provides a control method and device of an electronic expansion valve and an air conditioner, which are used for solving the problem that the air conditioner has a single valve adjusting period in an ultralow-temperature environment.

In order to achieve the above purpose, the embodiment of the invention adopts the following technical scheme:

in a first aspect, there is provided a control method of an electronic expansion valve, comprising: the refrigerant system is applied to the air conditioner and comprises a compressor, an outdoor heat exchanger, an electronic expansion valve and an indoor heat exchanger, wherein an air suction port of the compressor is connected with the indoor heat exchanger, an air exhaust port of the compressor is connected with the outdoor heat exchanger, and the outdoor heat exchanger is connected with the indoor heat exchanger through the electronic expansion valve; the electronic expansion valve is used for throttling the refrigerant in the refrigerant system. The method comprises the following steps: acquiring the outdoor environment temperature; if the outdoor environment temperature is lower than a preset temperature value, entering an ultralow temperature heating operation mode, and closing all electronic expansion valves within first preset time; determining a DSH difference value of the air conditioning system; the DSH difference is the difference between the actual DSH value and the target DSH value; setting an electronic expansion valve adjusting period according to the DSH difference; and adjusting the opening degree of the electronic expansion valve according to the adjustment period of the electronic expansion valve.

Based on the technical scheme, according to the control method of the electronic expansion valve provided by the invention, after the air conditioner compressor is started, under the condition that the operation state of the refrigerant system is in an unsteady state process, the air conditioner firstly obtains the outdoor environment temperature, if the outdoor environment temperature is lower than a preset temperature value, the air conditioner enters an ultralow temperature heating operation mode, and all the electronic expansion valves are closed within a first preset time so as to ensure that the refrigerant of the indoor unit quickly returns to the outdoor unit. Then, the air conditioner sets an electronic expansion valve adjusting period according to the DSH difference, and the electronic expansion valve adjusting period is more suitable for the actual running condition of the air conditioner by establishing a relation between the DSH difference and the electronic expansion valve adjusting period. Compared with the prior art, in the process of starting the air conditioner in the ultralow temperature environment, the electronic expansion valve is adjusted according to the fixed adjustment period no matter how large the DSH difference is, the control method of the electronic expansion valve provided by the invention divides the adjustment period of the electronic expansion valve according to the DSH difference, so that the adjustment time of the electronic expansion valve is more flexible, and the control method is more suitable for the actual operation condition of the air conditioner.

In a second aspect, a control device of an electronic expansion valve is provided, which is applied to a refrigerant system of an air conditioner, wherein the refrigerant system comprises a compressor, an outdoor heat exchanger, the electronic expansion valve and an indoor heat exchanger, an air suction port of the compressor is connected with the indoor heat exchanger, an air exhaust port of the compressor is connected with the outdoor heat exchanger, and the outdoor heat exchanger is connected with the indoor heat exchanger through the electronic expansion valve; the electronic expansion valve is used for throttling the refrigerant in the refrigerant system; characterized in that the device comprises: an acquisition unit for acquiring an outdoor ambient temperature; the processing unit is used for controlling the air conditioner to enter an ultralow temperature heating operation mode when the outdoor environment temperature is lower than a preset temperature value, closing the electronic expansion valve and enabling the electronic expansion valve to be in a closed state within a first preset time length; a determination unit for determining a DSH difference value of the air conditioning system; the DSH difference is the actual DSH value minus the target DSH value; the processing unit is also used for setting an electronic expansion valve adjusting period according to the DSH difference value; and adjusting the opening degree of the electronic expansion valve according to the adjustment period of the electronic expansion valve.

In a third aspect, a control device for an electronic expansion valve is provided, which comprises a memory, a processor, a bus and a communication interface; the memory is used for storing computer execution instructions, and the processor is connected with the memory through a bus; the processor executes computer-executable instructions stored by the memory to cause the control device of the electronic expansion valve to perform a control method of the electronic expansion valve as described in the first aspect and any one of the possible implementations of the first aspect.

In a fourth aspect, there is provided a computer-readable storage medium comprising instructions which, when run on a computer, cause the computer to perform a method of controlling an electronic expansion valve as provided in the first aspect above.

In a fifth aspect, the present invention provides an air conditioner comprising the control device for an electronic expansion valve described in the second or third aspect.

Drawings

FIG. 1 is a schematic diagram of a refrigerant system of an air conditioner;

FIG. 2 is a schematic diagram of a refrigerant system of an air conditioner;

fig. 3 is a schematic flow chart of a control method of an electronic expansion valve according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a method for dividing temperature intervals according to an embodiment of the present invention;

fig. 5 is a schematic flow chart of a control method of an electronic expansion valve according to another embodiment of the present invention;

fig. 6 is a schematic flow chart of a control method of an electronic expansion valve according to another embodiment of the present invention;

fig. 7 is a schematic structural diagram of a control device of an electronic expansion valve according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a control device of an electronic expansion valve according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of a control device of an electronic expansion valve according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that, in the embodiments of the present invention, words such as "exemplary" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "exemplary" or "e.g.," an embodiment of the present invention is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, use of the word "exemplary" or "such as" is intended to present concepts related in a concrete fashion.

For the convenience of clearly describing the technical solutions of the embodiments of the present invention, in the embodiments of the present invention, the words "first", "second", and the like are used for distinguishing the same items or similar items with basically the same functions and actions, and those skilled in the art can understand that the words "first", "second", and the like are not limited in number or execution order.

Fig. 1 is a schematic diagram of a refrigerant system of an air conditioner. The air conditioner refrigerant system mainly comprises four components: the heat exchanger comprises a compressor 11, an indoor heat exchanger 12, an electronic expansion valve 13 and an outdoor heat exchanger 14, wherein the compressor 11 is connected with the indoor heat exchanger 12 and the outdoor heat exchanger 14, the indoor heat exchanger 12 is connected with the outdoor heat exchanger 14 through the electronic expansion valve 13, and the four components are connected into a closed system to enable a refrigerant to circulate in the closed system and complete the processes of absorbing and releasing heat. Specifically, when the air conditioner is in a cooling state (as shown in the drawing, the direction indicated by the solid arrow indicates the flow direction of the refrigerant in the cooling state), the compressor 11 sucks and compresses the refrigerant from the indoor heat exchanger 12, and discharges the compressed refrigerant into the outdoor heat exchanger 14 to dissipate heat (in this case, the outdoor heat exchanger 14 is a condenser, and the refrigerant releases heat and condenses in the outdoor heat exchanger). After the refrigerant passes through the indoor heat exchanger 12 through the electronic expansion valve 13, the pressure in the indoor heat exchanger 12 is lower than the pressure in the outdoor heat exchanger 14 due to the throttling function of the electronic expansion valve 13, and the refrigerant absorbs heat in the indoor heat exchanger 12 (at this time, the indoor heat exchanger 12 is an evaporator, and the refrigerant absorbs heat and evaporates in the indoor heat exchanger 12), thereby completing the cycle process. When the air conditioner is in a heating state, the flow direction of the refrigerant is opposite to the direction in a cooling state (as shown in the figure, the direction indicated by the dotted arrow is the flow direction of the refrigerant in the cooling state), and the refrigerant is compressed by the compressor 11 and then releases heat and condenses in the indoor heat exchanger 12 (in this case, the indoor heat exchanger 12 is a condenser). Then, the refrigerant enters the outdoor heat exchanger 14, the pressure in the outdoor heat exchanger 14 is lower than the pressure in the indoor heat exchanger 12 due to the throttling action of the electronic expansion valve 13, and the refrigerant absorbs heat and evaporates in the outdoor heat exchanger 14 (at this time, the outdoor heat exchanger 14 is an evaporator), thereby completing the cycle process.

In addition, in order to enable the refrigerant in the refrigerant system of the air conditioner to complete the circulation process in different directions in the cooling and heating processes, as shown in fig. 2, the refrigerant system further includes a four-way valve 15. The four-way valve 15 is used to control the flow direction of the refrigerant. In order to avoid the presence of liquid refrigerant in the refrigerant sucked into the compressor 11, a gas-liquid separator 16 is provided at the inlet of the compressor.

When the inverter air conditioner heats in an ultralow-temperature environment, the rotating speeds of the compressor and the fan can be automatically controlled to be the maximum rotating speeds, and in order to obtain the optimal running state, the adjustment of the electronic expansion valve of the throttling device becomes the key point of control. When the ambient temperature is lower than the standard working condition, in order to prevent the superheat degree of the press from being unqualified for a long time due to too low cold start low pressure, the opening degree of an electronic expansion valve is generally increased by force, so that the flow rate of a refrigerant is increased, and the normal DSH control is recovered after a set value of the exhaust superheat Degree (DSH) is reached. After the low-temperature heating starting stage is exited, the actual DSH value is low, the EEV is adjusted from a small opening, and the opening needs to be gradually increased. In the prior art, a fixed valve adjusting mode of once per minute is generally adopted, the opening degree of the valve is adjusted according to an optimal library, and the maximum opening degree is 32 steps.

However, with the method of the above prior art, an optimal operation state corresponding to the current ambient temperature can be finally achieved, which results in a long valve adjusting period during actual operation, and the time required for the entire low-temperature heating to be stable is more than one hour.

Aiming at the technical problem, the method provided by the invention does not adopt a mode of fixing the regulating valve, but sets the regulating valve period according to the DSH difference value and regulates according to the regulating valve period corresponding to the DSH difference value.

Based on the above principle, the embodiment of the invention provides a control method of an electronic expansion valve, which is applied to a refrigerant system of an air conditioner. The refrigerant system comprises a compressor, an outdoor heat exchanger, an electronic expansion valve and an indoor heat exchanger, wherein an air suction port of the compressor is connected with the indoor heat exchanger, an air exhaust port of the compressor is connected with the outdoor heat exchanger, and the outdoor heat exchanger is connected with the indoor heat exchanger through the electronic expansion valve; the electronic expansion valve is used for throttling the refrigerant in the refrigerant system. The refrigerant system according to the present invention can be described with reference to fig. 1.

As shown in fig. 3, a control method of an electronic expansion valve according to an embodiment of the present invention includes:

s101, the air conditioner acquires the outdoor environment temperature.

Optionally, the outdoor ambient temperature may be obtained according to a set sampling frequency by an outdoor temperature sensor disposed on the outdoor heat exchanger, and is directly output to one I/O port of the controller. The outdoor ambient temperature can also be measured by temperature sensors located elsewhere outdoors and transmitted to the controller via different communication means.

S102, if the outdoor environment temperature is lower than the preset temperature value, the air conditioner enters an ultralow temperature heating operation mode, the electronic expansion valve is closed, and the electronic expansion valve is in a closed state within a first preset time.

The preset temperature value can be set according to the saturation temperature of different refrigerants, and is usually-10 ℃ to-25 ℃, and under such environmental conditions, the industry generally considers the environment as an ultra-low temperature environment.

For example, as shown in fig. 4, if the outdoor ambient temperature is different according to the temperature, it is divided into a section a: the temperature control method comprises the following steps of (-10 ℃ C.), and a B interval (10 ℃ C.) (-0 ℃ C.) (5 ℃ C.), wherein the A interval represents an ultralow temperature interval, the B interval represents a low temperature interval, and the C interval represents a common low temperature interval.

In the ultra-low temperature environment, the refrigerant in the indoor unit can be quickly returned to the outdoor unit by closing the electronic expansion valve.

It should be noted that the first preset time period may be reasonably configured according to data obtained through experimental tests. The embodiment of the application does not limit the specific value of the first preset duration.

S103, the air conditioner determines the DSH difference value of the air conditioning system.

Wherein, DSH is the exhaust superheat degree of the air conditioning system. Specifically, DSH is the exhaust temperature T_dInner disc temperature T_c. The DSH difference is the actual DSH value minus the target DSH value. That is, the DSH difference is the DSH actual value — the DSH target value, which is a target value set in advance.

It is understood that the DSH difference value is used to indicate a degree of deviation of the DSH value from the DSH target value in the current state of the air conditioner. If the DSH difference is negative, the electronic expansion valve is required to be opened too much, and the opening needs to be reduced and the throttle needs to be increased. Similarly, if the DSH difference is a positive number, it indicates that the opening of the electronic expansion valve is too small, and it is necessary to increase the opening and decrease the throttle.

And S104, setting an electronic expansion valve adjusting period by the air conditioner according to the DSH difference value.

Specifically, as can be seen from the meaning of the DSH difference in S103, if the DSH difference is a positive number, the larger the DSH difference is, the more the actual DSH value of the air conditioning system deviates from the target DSH value; if the DSH difference is negative, the smaller the DSH difference, the more the actual DSH value of the air conditioning system deviates from the target DSH value. Therefore, the larger the DSH difference, the faster the adjustment of the electronic expansion valve needs to be made to bring the actual DSH value into rapid proximity with the target DSH value, and the shorter the adjustment period needs to be set.

For example, the electronic expansion valve adjustment period is typically expressed in units of "seconds" by the letter S, and the DSH difference by the letter T. Table 1 below shows the different DSH differences, corresponding to the electronic expansion valve adjustment cycles.

TABLE 1

DSH difference (T)	(0,5]	(5,15]	(15,20]
				Adjustment period (S)	60	30	10

And S105, the air conditioner adjusts the opening degree of the electronic expansion valve according to the electronic expansion valve adjusting period.

For example, the opening degree of the electronic expansion valve is usually expressed by a letter b in units of "steps". If the DSH difference is equal to 20, the electronic expansion valve is increased one step every 10 seconds according to the corresponding adjustment period in table 1.

In one possible design, the air conditioner determines the DSH difference value again every other preset time, then continues to adjust the opening of the electronic expansion valve according to the adjustment period corresponding to the determined DSH difference value, and stops adjusting until the DSH difference value is determined to be zero.

Optionally, referring to fig. 5, after step S102, the embodiment of the present invention further includes the following steps: S201-S202.

S201, the air conditioner calculates a first opening degree of the electronic expansion valve according to the target frequency of the compressor.

As a possible implementation manner, the air conditioner obtains the first opening degree of the electronic expansion valve by the formula EEV ═ K × F + B- △ E1, where EEV is an opening degree value of the electronic expansion valve, K is a weighting coefficient, F is a compressor frequency, B is a fixed value, and △ E1 is a correction value.

S202, the air conditioner enables the electronic expansion valve to be in the first opening degree until the DSH difference value is one half of the target DSH value.

It should be noted that the above steps S201 to S202 are to raise the DSH actual value and maintain a certain low pressure to avoid long-time liquid return of the compressor.

Optionally, referring to fig. 6, after step S202, the embodiment of the present invention further includes the following steps:

s301, the air conditioner adjusts the opening degree of the electronic expansion valve from a first opening degree to a second opening degree, and the electronic expansion valve is in the second opening degree within a second time.

Wherein the second opening degree is twice as large as the first opening degree. The second time is one-half of the first time, and the first time is the duration of the electronic expansion valve at the first opening degree.

It should be noted that, through the above step S301, the problem of too high exhaust gas caused by too small opening of the electronic expansion valve can be avoided; in addition, the above step S301 can also avoid some problems caused by long-time adjustment of the opening of the electronic expansion valve of the air conditioner, such as long power fluctuation time, long time for reaching a steady state, and the like.

According to the control method of the electronic expansion valve provided by the embodiment of the invention, in the process of starting the air conditioner in an ultralow temperature environment, the adjustment period of the electronic expansion valve is divided according to the DSH difference value, so that the adjustment time is more flexible. Under the ultra-low temperature environment, the air conditioner can set up shorter electronic expansion valve adjustment cycle according to the DSH difference when just starting, so just reduced the regulation time in the start-up process, need not to increase under the condition of extra equipment and input, realized the purpose of complete machine system steady operation.

The embodiment of the invention provides a control device of an electronic expansion valve, which is applied to a refrigerant system of an air conditioner, wherein the refrigerant system comprises a compressor, an outdoor heat exchanger, the electronic expansion valve and an indoor heat exchanger; the electronic expansion valve is used for throttling the refrigerant in the refrigerant system. The control device of the electronic expansion valve is used for executing the control method of the electronic expansion valve.

In the embodiment of the present invention, the control device of the electronic expansion valve may be divided into function modules according to the above method, for example, each function module may be divided according to each function, or two or more functions may be integrated into one processing module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. It should be noted that, the division of the modules in the embodiment of the present invention is schematic, and is only a logic function division, and there may be another division manner in actual implementation.

Fig. 7 is a schematic diagram of a possible structure of a control device for an electronic expansion valve according to an embodiment of the present invention, in a case where each function module is divided according to each function. Specifically, the control device for an electronic expansion valve includes: an acquisition unit 201, a processing unit 202, and a determination unit 203. Wherein:

an acquisition unit 201 for acquiring an outdoor ambient temperature;

the processing unit 202 is configured to control the air conditioner to enter an ultra-low temperature heating operation mode, close the electronic expansion valve, and enable the electronic expansion valve to be in a closed state within a first preset time period when the outdoor environment temperature is lower than a preset temperature value;

a determination unit 203 for determining a DSH difference value of the air conditioning system; the DSH difference is the actual DSH value minus the target DSH value;

the processing unit 202 is further configured to set an electronic expansion valve adjustment period according to the DSH difference; and adjusting the opening degree of the electronic expansion valve according to the adjustment period of the electronic expansion valve.

In one embodiment, closing the electronic expansion valve and maintaining the electronic expansion valve in a closed state for a first preset time period comprises: calculating a first opening degree of the electronic expansion valve according to the target frequency of the compressor; and enabling the electronic expansion valve to be in the first opening degree until the DSH difference value is one half of the target DSH value.

In one embodiment, the processing unit 202 is further configured to, after the DSH difference is one-half of the DSH target value, adjust the opening degree of the electronic expansion valve from the first opening degree to a second opening degree, and make the electronic expansion valve always at the second opening degree for a second time, the second opening degree being twice the first opening degree, the second time being one-half of a first time, and the first time being a duration of the first opening degree of the electronic expansion valve.

In one embodiment, calculating the first opening degree of the electronic expansion valve according to the target frequency of the compressor comprises substituting the target frequency of the compressor into an equation of EEV F + B- △ E1 to obtain the first opening degree of the electronic expansion valve, wherein EEV is an opening degree value of the electronic expansion valve, K is a weighting coefficient, F is the compressor frequency, B is a fixed value, and △ E1 is a corrected value.

It should be noted that, for other corresponding descriptions corresponding to each unit in the control device of the electronic expansion valve provided in the embodiment of the present invention, reference may be made to fig. 3 and the corresponding description of fig. 3 in the foregoing, and details are not repeated herein.

In the case of an integrated unit, fig. 8 shows a schematic view of a possible configuration of the control device of the electronic expansion valve described above. The control device 30 for an electronic expansion valve includes: a storage unit 301, a processing unit 302, and an interface unit 303. The processing unit 302 is configured to control and manage the operation of the control device of the electronic expansion valve, for example, the processing unit 302 is configured to support the control device of the electronic expansion valve to execute the processes S101 to S105 in fig. 3. A memory unit 301 for program codes and data of the control means of the electronic expansion valve. The interface unit 303 is used for connecting with other external devices and receiving input content, and for example, the interface unit may be connected with an air conditioning component such as an electronic expansion valve, a temperature sensor, and a compressor, so as to transmit a signal to the air conditioning component or receive a signal transmitted by the air conditioning component.

For example, the processing unit is a processor, the storage unit is a memory, and the interface unit is a transceiver. The control device of the electronic expansion valve is shown in fig. 9, and includes a transceiver 403, a processor 402, a memory 401, and a bus 404, where the transceiver 403 and the processor 402 are connected to the memory 401 through the bus 404.

Processor 402 may be a general-purpose Central Processing Unit (CPU), a microprocessor, an Application-Specific Integrated Circuit (ASIC), or one or more Integrated circuits configured to control the execution of programs in accordance with the present invention.

The Memory 401 may be a Read-Only Memory (ROM) or other types of static storage devices that can store static information and instructions, a Random Access Memory (RAM) or other types of dynamic storage devices that can store information and instructions, an electrically erasable Programmable Read-Only Memory (EEPROM), a Compact Disc Read-Only Memory (CD-ROM) or other optical Disc storage, optical Disc storage (including Compact Disc, laser Disc, optical Disc, digital versatile Disc, blu-ray Disc, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited to these. The memory may be self-contained and coupled to the processor via a bus. The memory may also be integral to the processor.

The memory 401 is used for storing application program codes for executing the present invention, and is controlled by the processor 402. The transceiver 403 is used for receiving the content input by the external device, and the processor 402 is used for executing the application program code stored in the memory 401, so as to implement the control device of the electronic expansion valve described in the embodiment of the present invention.

The computer instructions may be stored in or transmitted from one computer-readable storage medium to another computer-readable storage medium, e.g., from one website, computer, server, or data center, by wire (e.g., coaxial cable, fiber optics, Digital Subscriber line (Digital Subscriber line) L ine, DS L) or wirelessly (e.g., infrared, wireless, microwave, etc.) to another website, computer, server, or data center, may be transmitted from one website, computer, server, or data center to another website, computer, or data center via a wired (e.g., Digital Subscriber line (Digital Subscriber line) L ine, DS L) or wireless (e.g., infrared, wireless, microwave, etc.) medium, which may be any Solid State storage medium (e.g., a Solid State Disk, optical Disk, magnetic Disk, optical Disk.

In addition, the embodiment of the invention also provides an air conditioner, which comprises the control device of the electronic expansion valve.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims

1. A control method of an electronic expansion valve is applied to a refrigerant system of an air conditioner, wherein the refrigerant system comprises a compressor, an outdoor heat exchanger, an electronic expansion valve and an indoor heat exchanger, an air suction port of the compressor is connected with the indoor heat exchanger, an air exhaust port of the compressor is connected with the outdoor heat exchanger, and the outdoor heat exchanger is connected with the indoor heat exchanger through the electronic expansion valve; the electronic expansion valve is used for throttling the refrigerant in the refrigerant system; characterized in that the method comprises:

acquiring the outdoor environment temperature;

if the outdoor environment temperature is lower than a preset temperature value, entering an ultralow temperature heating operation mode, closing the electronic expansion valve, and enabling the electronic expansion valve to be in a closed state within a first preset time;

determining the difference value of the exhaust superheat DSH of the air conditioning system; the DSH difference is the actual DSH value minus the target DSH value;

setting an electronic expansion valve adjusting period according to the DSH difference;

and adjusting the opening degree of the electronic expansion valve according to the adjustment period of the electronic expansion valve.

2. The control method of an electronic expansion valve according to claim 1, further comprising:

calculating a first opening degree of the electronic expansion valve according to the target frequency of the compressor;

and enabling the electronic expansion valve to be in the first opening degree until the DSH difference value is one half of the target DSH value.

3. The method for controlling an electronic expansion valve according to claim 2, wherein said calculating a first opening degree of the electronic expansion valve based on a target frequency of the compressor comprises:

and substituting the target frequency of the compressor into a formula of EEV (K) F + B- △ E1 to obtain a first opening degree of the electronic expansion valve, wherein EEV is the opening degree value of the electronic expansion valve, K is a weighting coefficient, F is the frequency of the compressor, B is a fixed value, and △ E1 is a corrected value.

4. The control method of the electronic expansion valve according to claim 2 or 3, characterized by further comprising:

after the DSH difference is one-half of the DSH target value, adjusting the opening degree of the electronic expansion valve from the first opening degree to a second opening degree, and making the electronic expansion valve be at the second opening degree within a second time, the second opening degree being twice the first opening degree, the second time being one-half of a first time, the first time being a duration time during which the electronic expansion valve is at the first opening degree.

5. A control device of an electronic expansion valve is applied to a refrigerant system of an air conditioner, wherein the refrigerant system comprises a compressor, an outdoor heat exchanger, the electronic expansion valve and an indoor heat exchanger, an air suction port of the compressor is connected with the indoor heat exchanger, an air exhaust port of the compressor is connected with the outdoor heat exchanger, and the outdoor heat exchanger is connected with the indoor heat exchanger through the electronic expansion valve; the electronic expansion valve is used for throttling the refrigerant in the refrigerant system; characterized in that, the control device of the electronic expansion valve comprises:

an acquisition unit for acquiring an outdoor ambient temperature;

the processing unit is used for controlling the air conditioner to enter an ultralow temperature heating operation mode when the outdoor environment temperature is lower than a preset temperature value, closing the electronic expansion valve and enabling the electronic expansion valve to be in a closed state within a first preset time length; determining the difference value of the exhaust superheat DSH of the air conditioning system; the DSH difference is the actual DSH value minus the target DSH value; setting an electronic expansion valve adjusting period according to the DSH difference; and adjusting the opening degree of the electronic expansion valve according to the adjustment period of the electronic expansion valve.

6. Control device for an electronic expansion valve according to claim 5,

the processing unit is further used for calculating a first opening degree of the electronic expansion valve according to the target frequency of the compressor; and enabling the electronic expansion valve to be in the first opening degree until the DSH difference value is one half of the target DSH value.

7. Control device for an electronic expansion valve according to claim 6,

the processing unit is specifically configured to substitute the target frequency of the compressor into a formula, i.e., EEV ═ K × F + B- △ E1, to obtain a first opening degree of the electronic expansion valve, where EEV is an opening degree value of the electronic expansion valve, K is a weighting coefficient, F is a compressor frequency, B is a fixed value, and △ E1 is a correction value.

8. The control device for an electronic expansion valve according to claim 6, further comprising:

the processing unit is further configured to, after the DSH difference is one-half of the DSH target value, adjust the opening degree of the electronic expansion valve from the first opening degree to a second opening degree, and enable the electronic expansion valve to be at the second opening degree within a second time, where the second opening degree is twice the first opening degree, the second time is one-half of a first time, and the first time is a duration time during which the electronic expansion valve is at the first opening degree.

9. An air conditioner characterized by comprising a control device of an electronic expansion valve according to any one of claims 5 to 8.