CN113124541A

CN113124541A - Method and device for judging reverse connection of expansion valve, controller and air conditioner

Info

Publication number: CN113124541A
Application number: CN202110399328.5A
Authority: CN
Inventors: 杨培兴; 曹勋; 黄超
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2021-04-14
Filing date: 2021-04-14
Publication date: 2021-07-16
Anticipated expiration: 2041-04-14
Also published as: CN113124541B

Abstract

The application relates to a method and a device for judging reverse connection of an expansion valve, a controller and an air conditioner. The unit can automatically judge whether the heating expansion valve and the supercooling expansion valve are reversely connected or not through preset judging conditions, so that the unit can be prevented from being broken down or damaged due to the reverse connection of the expansion valves on the basis, manual participation is not needed in the judging process, and the labor cost can be effectively saved.

Description

Method and device for judging reverse connection of expansion valve, controller and air conditioner

Technical Field

The application relates to the technical field of air conditioners, in particular to a method and a device for judging reverse connection of an expansion valve, a controller and an air conditioner.

Background

In the development, production, and after-sales processes of the air conditioning unit, an Electronic expansion valve (EXV) terminal may need to be detached.

The heating expansion valves and the supercooling expansion valves of part of the units are consistent in terminal structure, the heating expansion valves and the supercooling expansion valves are connected reversely in the dismounting process, the unit is easy to cause faults when the unit operates under the condition, and the unit can be damaged even if the unit does not have faults in a short period and operates for a long time. In the prior art, no related detection method except manual confirmation can automatically judge whether the heating expansion valve and the supercooling expansion valve are reversely connected.

Disclosure of Invention

The application provides a method and a device for judging reverse connection of an expansion valve, a controller and an air conditioner, which aim to solve the problem that whether a heating expansion valve and a supercooling expansion valve are in reverse connection or not cannot be automatically judged in the prior art.

The above object of the present application is achieved by the following technical solutions:

in a first aspect, an embodiment of the present application provides a method for determining reverse connection of an expansion valve, including:

in the heating mode, judging whether the opening degree of the supercooling expansion valve is larger than zero;

if the opening degree of the supercooling expansion valve is not larger than zero, judging whether the refrigerant effectively exchanges heat at the condenser or not based on a first preset judgment condition;

and if the refrigerant does not effectively exchange heat at the condenser in the heating mode, determining that the supercooling expansion valve and the heating expansion valve are reversely connected.

Optionally, the determining, based on a first preset determination condition, whether the refrigerant is subjected to effective heat exchange at the condenser includes:

and if the absolute value of the difference value between the temperature of the outlet side of the condenser and the ambient temperature is less than or equal to a first preset temperature, and/or the difference value between the temperature of the low pressure side of the compressor and the ambient temperature is less than or equal to a second preset temperature, and/or the difference value between the temperature of the inlet side of the gas-liquid separator and the temperature of the outlet side of the gas-liquid separator is greater than or equal to a third preset temperature, determining that the refrigerant does not effectively exchange heat at the condenser.

Optionally, the determining that the subcooling expansion valve and the heating expansion valve are reversely connected further includes:

when the refrigerant is determined not to be subjected to effective heat exchange at the condenser in the heating mode, based on the control logic of the current mode, the supercooling expansion valve and the heating expansion valve are exchanged and controlled, and after the refrigerant is continuously operated for the first preset time, whether the refrigerant is subjected to effective heat exchange at the condenser is judged again;

the determining of the inverse connection of the supercooling expansion valve and the heating expansion valve specifically comprises the following steps:

and if the effective heat exchange of the refrigerant at the condenser is determined after the judgment is carried out again, the supercooling expansion valve and the heating expansion valve are determined to be reversely connected.

Optionally, the method further includes:

if the opening degree of the supercooling expansion valve is larger than zero, judging whether the absolute value of the difference value between the opening degree of the heating expansion valve and the opening degree of the supercooling expansion valve is larger than or equal to a first preset opening degree or not;

if the absolute value of the difference value between the opening degree of the heating expansion valve and the opening degree of the supercooling expansion valve is greater than or equal to the first preset opening degree, and the opening degree of the heating expansion valve is greater than the opening degree of the supercooling expansion valve, judging whether the opening degree of the heating expansion valve is smaller than the opening degree to be opened or not based on a second preset judgment condition;

and if the opening degree of the heating expansion valve is smaller than the opening degree to be opened, controlling the opening degree of the supercooling expansion valve to be equal to zero and controlling the opening degree of the heating expansion valve to be equal to a second preset opening degree, and after continuously operating for a second preset time, judging whether the refrigerant is subjected to effective heat exchange at the condenser based on the first preset judgment condition again.

Optionally, the method further includes:

if the absolute value of the difference value between the opening degree of the heating expansion valve and the opening degree of the supercooling expansion valve is greater than or equal to the first preset opening degree, and the opening degree of the heating expansion valve is smaller than the opening degree of the supercooling expansion valve, judging whether the opening degree of the heating expansion valve is greater than the opening degree to be opened or not based on a third preset judgment condition;

and if the opening degree of the heating expansion valve is larger than the opening degree to be opened, controlling the opening degree of the supercooling expansion valve to be equal to zero and controlling the opening degree of the heating expansion valve to be equal to a third preset opening degree, and after continuously running for a second preset time, judging whether the refrigerant is subjected to effective heat exchange at the condenser based on the first preset judgment condition again.

Optionally, the determining, based on a second preset determination condition, whether the opening degree of the heating expansion valve is smaller than the opening degree to be opened specifically includes:

and if the difference between the ambient temperature and the temperature of the low pressure side of the compressor is greater than or equal to a fourth preset temperature and/or the difference between the temperature of the inlet side of the gas-liquid separator and the temperature of the low pressure side of the compressor is greater than or equal to a fifth preset temperature, determining that the opening degree of the heating expansion valve is smaller than the opening degree to be opened.

Optionally, the determining, based on a third preset determination condition, whether the opening degree of the heating expansion valve is greater than the opening degree to be opened specifically includes:

and if the difference between the ambient temperature and the temperature of the low pressure side of the compressor is less than or equal to a sixth preset temperature and/or the difference between the temperature of the inlet side of the gas-liquid separator and the temperature of the low pressure side of the compressor is less than or equal to a seventh preset temperature, determining that the opening degree of the heating expansion valve is greater than the opening degree to be opened.

Optionally, the method further includes:

in the refrigeration mode, judging whether the opening degree of the supercooling expansion valve is larger than zero;

if the opening degree of the supercooling expansion valve is not larger than zero, judging whether the refrigerant effectively exchanges heat at the condenser or not based on a fourth preset judgment condition;

and if the refrigerant does not effectively exchange heat at the condenser in the refrigeration mode, determining that the supercooling expansion valve and the heating expansion valve are reversely connected.

Optionally, the determining, based on a fourth preset determination condition, whether the refrigerant is subjected to effective heat exchange at the condenser includes:

and if the temperature of the high-pressure side of the compressor is continuously higher than or equal to the eighth preset temperature within the third preset time and/or the absolute value of the difference value between the ambient temperature and the temperature of the liquid outlet side of the subcooler is lower than or equal to the ninth preset temperature, determining that the refrigerant does not effectively exchange heat at the condenser.

Optionally, the method further includes:

if the opening degree of the supercooling expansion valve is larger than zero, judging whether the difference value between the opening degree of the heating expansion valve and the opening degree of the supercooling expansion valve is larger than or equal to a fourth preset opening degree;

if the difference value between the opening degree of the heating expansion valve and the opening degree of the supercooling expansion valve is larger than or equal to a fourth preset opening degree, judging whether the difference value between the temperature of the outlet side of the gas-liquid separator and the temperature of the low pressure side of the compressor is continuously smaller than or equal to a tenth preset temperature within continuous fourth preset time;

and if the difference value is continuously less than or equal to a tenth preset temperature within a continuous fourth preset time, controlling the opening degree of the supercooling expansion valve to be equal to zero and the opening degree of the heating expansion valve to be equal to a fifth preset opening degree, and after continuously running for a fifth preset time, judging whether the refrigerant is subjected to effective heat exchange at the condenser based on the fourth preset judgment condition again.

Optionally, determining that the subcooling expansion valve and the heating expansion valve are reversely connected, and then:

and controlling the unit to stop and reporting the reverse connection fault of the expansion valve.

and exchanging and controlling the supercooling expansion valve and the heating expansion valve based on the control logic of the current mode until the unit is powered off.

Optionally, the determining whether the opening degree of the subcooling expansion valve is greater than zero specifically includes:

and after the unit is at least electrified and operated for the sixth preset time, judging whether the opening degree of the supercooling expansion valve is larger than zero or not.

In a second aspect, an embodiment of the present application further provides a device for determining reverse connection of an expansion valve, including:

the first judgment module is used for judging whether the opening degree of the supercooling expansion valve is larger than zero or not in the heating mode;

the second judgment module is used for judging whether the refrigerant effectively exchanges heat at the condenser or not based on the first preset judgment condition if the opening degree of the supercooling expansion valve is not larger than zero;

and the determining module is used for determining that the supercooling expansion valve and the heating expansion valve are reversely connected if the refrigerant does not effectively exchange heat at the condenser in the heating mode.

Optionally, the first determining module is further configured to determine whether an opening degree of the subcooling expansion valve is greater than zero in the cooling mode;

the second judgment module is also used for judging whether the refrigerant effectively exchanges heat at the condenser or not based on a fourth preset judgment condition if the opening degree of the supercooling expansion valve is not larger than zero;

the determining module is also used for determining that the supercooling expansion valve and the heating expansion valve are reversely connected if the refrigerant does not effectively exchange heat at the condenser in the refrigeration mode.

In a third aspect, an embodiment of the present application further provides a controller of an air conditioner, including:

a memory and a processor coupled to the memory;

the memory for storing a program for implementing at least the method of any one of the first aspect;

the processor is used for calling and executing the program stored in the memory.

In a fourth aspect, embodiments of the present application further provide an air conditioner, which is provided with the controller of the air conditioner described in the third aspect.

The technical scheme provided by the embodiment of the application can have the following beneficial effects:

in the technical scheme provided by the embodiment of the application, in the heating mode, whether the opening degree of the supercooling expansion valve is larger than zero or not can be automatically judged; if the opening degree of the supercooling expansion valve is not larger than zero, judging whether the refrigerant effectively exchanges heat at the condenser or not based on a first preset judgment condition; and if the refrigerant does not effectively exchange heat at the condenser in the heating mode, determining that the supercooling expansion valve and the heating expansion valve are reversely connected. According to the arrangement, the unit can automatically judge whether the heating expansion valve and the supercooling expansion valve are reversely connected through the preset judging condition, so that the unit can be prevented from being broken down or damaged due to the reverse connection of the expansion valves on the basis, the judging process does not need manual participation, and the labor cost can be effectively saved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and together with the description, serve to explain the principles of the application.

Fig. 1 is a schematic structural diagram of an air conditioning system according to an embodiment of the present disclosure;

fig. 2 is a schematic flowchart of a method for determining reverse connection of an expansion valve according to an embodiment of the present disclosure;

fig. 3 is a schematic flowchart of another method for determining reverse connection of an expansion valve according to an embodiment of the present disclosure;

fig. 4 is a schematic structural diagram of a device for determining reverse connection of an expansion valve according to an embodiment of the present disclosure;

fig. 5 is a schematic structural diagram of a controller of an air conditioner according to an embodiment of the present application.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

In order to solve the problems of the background art, the present application provides a method for automatically detecting and determining whether a heating expansion valve and a subcooling expansion valve are connected in reverse.

In order to make the technical solution of the present application easier to understand, a description is first given of a structure and an operation principle of an air conditioning unit to which the technical solution of the present application can be applied. Referring to fig. 1, fig. 1 is a schematic structural diagram of an air conditioning system according to an embodiment of the present application. As shown in fig. 1, the system includes an indoor unit and an outdoor unit, the outdoor unit mainly includes a compressor, a four-way valve, a condenser, a heating expansion valve (i.e., heating EXV in fig. 1), a supercooling expansion valve (i.e., supercooling EXV in fig. 1), a subcooler, a gas-liquid separator (gas-liquid separator for short), an outdoor unit fan, a pipeline connecting the components, and a plurality of pressure sensors and temperature sensors (temperature sensing bags) disposed on the pipeline or the components; the indoor unit mainly includes an evaporator, an indoor unit expansion valve (i.e., an indoor unit EXV in fig. 1), an indoor unit blower, and a pipeline connecting the respective components.

During heating, low-pressure and low-temperature refrigerants are changed into high-temperature and high-pressure refrigerants after passing through the compressor, then enter the indoor unit through the four-way valve, and enter the outdoor unit after being subjected to heat dissipation and condensation in the evaporator of the indoor unit under the air supply effect of the fan of the indoor unit. The refrigerant passes through a heating expansion valve in the outdoor unit for throttling and pressure reduction, is quickly evaporated in a condenser under the air supply action of an outdoor unit fan, then enters a gas-liquid separator through a four-way valve, and finally enters a compressor. As can be seen from fig. 1, when the refrigerant enters the outdoor unit, the refrigerant may also be throttled by the subcooling expansion valve before passing through the heating expansion valve, and then enter the gas-liquid separator. The refrigerant flowing through the supercooling expansion valve and the refrigerant of the heating expansion valve exchange heat in the subcooler.

During refrigeration, low-pressure and low-temperature refrigerants are changed into high-temperature and high-pressure refrigerants after passing through the compressor, then enter the condenser through the four-way valve, are subjected to heat dissipation and condensation under the air supply effect of the outer fan, then enter the indoor unit, are subjected to throttling and pressure reduction through the expansion valve of the indoor unit, are evaporated in the evaporator under the air supply effect of the inner fan, then enter the outdoor unit, enter the air separator through the four-way valve, and then enter the compressor. As can be seen from fig. 1, after the refrigerant flows out of the heating expansion valve, a part of the refrigerant may be throttled by the subcooling expansion valve and then enters the air separator. The refrigerant flowing through the supercooling expansion valve and the refrigerant entering the indoor unit exchange heat in the subcooler.

The low-pressure sensor is arranged on the low-pressure side (inlet side) of the compressor and used for detecting the low pressure of the unit; the high pressure sensor is arranged on the high pressure side (outlet side) of the compressor and used for detecting the high pressure of the unit. In addition, the temperature sensing bulb comprises a gas inlet pipe temperature sensing bulb, a gas outlet pipe temperature sensing bulb, an environment temperature sensing bulb, an exhaust temperature sensing bulb, a supercooled gas outlet temperature sensing bulb, a supercooled liquid outlet temperature sensing bulb and a defrosting temperature sensing bulb (condenser outlet pipe temperature sensing bulb), and is respectively used for detecting the inlet side temperature of the gas-liquid separator, the outlet side temperature of the gas-liquid separator, the environment temperature, the high-pressure side temperature of the compressor, the outlet side temperature of the gas-liquid separator, the outlet side temperature of the supercooler liquid and the defrosting temperature (condenser outlet side temperature). The air conditioner controller realizes the operation control of the unit by acquiring the detection parameters of the sensors.

Based on the above system, in order to detect whether the heating expansion valve and the subcooling expansion valve are reversely connected after being assembled and disassembled, the present embodiment provides a method for determining reverse connection of the expansion valves. Referring to fig. 2, fig. 2 is a schematic flowchart of a method for determining reverse connection of an expansion valve according to an embodiment of the present disclosure.

As shown in fig. 2, the method comprises at least the following steps:

s201: in the heating mode, judging whether the opening degree of the supercooling expansion valve is larger than zero;

specifically, in the heating mode, as described in the above principle, if the expansion valve is normally connected, the heating expansion valve is necessarily opened, and the subcooling expansion valve may be completely closed or opened to a certain degree (depending on the operation parameters of the unit under the current operating conditions). Therefore, the present embodiment first detects whether the opening degree of the subcooling expansion valve is larger than zero, in order to determine whether two expansion valves (in the present application, "two expansion valves" refer to the subcooling expansion valve and the heating expansion valve, the same applies hereinafter) are connected in reverse according to the corresponding situation.

S202: if the opening degree of the supercooling expansion valve is not larger than zero, judging whether the refrigerant effectively exchanges heat at the condenser or not based on a first preset judgment condition;

specifically, if the opening degree of the subcooling expansion valve is not greater than zero, that is, the subcooling expansion valve is completely closed, in this case, if the two expansion valves are not reversely connected, all the refrigerant entering the outdoor unit enters the condenser through the heating expansion valve to perform heat exchange (absorb heat in the heating mode), therefore, in this embodiment, whether the two expansion valves are reversely connected is determined by judging whether the refrigerant is effectively heat exchanged at the condenser, where the effective heat exchange of the refrigerant at the condenser refers to sufficient heat exchange of the refrigerant at the condenser (which can meet the current heating requirement).

Further, as a feasible implementation manner, based on the first preset determination condition, determining whether the refrigerant is subjected to effective heat exchange at the condenser specifically may include:

That is, the refrigerant may be considered to be not exchanging heat efficiently at the condenser when one or more of the following three conditions occur: absolute value of difference value between temperature at outlet side of condenser and ambient temperature is less than or equal to first preset temperature; the difference value between the temperature of the low-pressure side of the compressor and the ambient temperature is less than or equal to a second preset temperature; and the difference value between the temperature of the inlet side of the gas-liquid separator and the temperature of the outlet side of the gas-liquid separator is greater than or equal to a third preset temperature.

The first case shows that the temperature (defrosting temperature) at the outlet side of the condenser is close to the ambient temperature, which indicates that the refrigerant does not pass through the condenser, because the pipeline between the subcooler and the condenser is blocked, or the heating expansion valve is not opened, and if the heating expansion valve is opened but not opened, the heating expansion valve and the subcooling expansion valve are reversely connected; the second case represents that the low pressure of the unit in the environment is low, and the reason may be that the refrigerant in the inlet pipe (inlet side) of the gas-liquid separator does not effectively absorb heat by the condenser, the gaseous refrigerant is little, so that the low pressure detected by the low pressure sensor is low, and the reason that the refrigerant does not effectively absorb heat by the condenser may be that the heating expansion valve is not opened; and thirdly, the temperature of the outlet side of the gas-liquid separator is obviously lower than the temperature of the inlet side of the gas-liquid separator, so that the temperature of the outlet side of the gas-liquid separator is obviously lower than the temperature of the inlet side of the gas-liquid separator due to the fact that the refrigerant in the gas-liquid separator is continuously evaporated and absorbs heat, and the reason that a large amount of refrigerant enters the gas-liquid separator may be that the heating expansion valve is not opened.

That is, when the heating expansion valve and the subcooling expansion valve are in reverse connection, the system still adopts a normal control mode to control the heating expansion valve and the subcooling expansion valve, so that the opening and closing states of the heating expansion valve and the subcooling expansion valve are opposite to those in a normal case, specifically, in a normal case, the heating expansion valve is opened, the subcooling expansion valve is closed, and in an abnormal case, the heating expansion valve is closed, and the subcooling expansion valve is opened, so that in an abnormal case, a large amount of refrigerant entering the outdoor unit from the indoor unit does not enter the condenser through the heating expansion valve, but directly enters the gas-liquid separator through the subcooling expansion valve, thereby causing an abnormal case that the refrigerant does not effectively exchange heat at the condenser.

It should be noted that, in order to improve the accuracy of the determination, when determining whether the refrigerant is in effective heat exchange at the condenser based on the first preset determination condition, it is preferable that when all of the above-mentioned (i) and (ii) occur, it is determined that the refrigerant is not in effective heat exchange at the condenser. Of course, it should be understood that, in the embodiment, the three conditions of (i) and (ii) corresponding to the first preset determination condition are merely exemplary, and in practical applications, other determination conditions may also be used to determine whether the refrigerant is to exchange heat effectively at the condenser, which is not limited thereto. In the same way, the feasible implementation methods of the second preset judgment condition, the third preset judgment condition and other judgment conditions given below are also exemplary and should not be considered as limiting the application.

S203: and if the refrigerant does not effectively exchange heat at the condenser in the heating mode, determining that the supercooling expansion valve and the heating expansion valve are reversely connected.

By the scheme, in the heating mode, the unit can automatically judge whether the opening degree of the supercooling expansion valve is larger than zero; if the opening degree of the supercooling expansion valve is not larger than zero, judging whether the refrigerant effectively exchanges heat at the condenser or not based on a first preset judgment condition; and if the refrigerant does not effectively exchange heat at the condenser in the heating mode, determining that the supercooling expansion valve and the heating expansion valve are reversely connected. According to the arrangement, the unit can automatically judge whether the heating expansion valve and the supercooling expansion valve are reversely connected through the preset judging condition, so that the unit can be prevented from being broken down or damaged due to the reverse connection of the expansion valves on the basis, the judging process does not need manual participation, and the labor cost can be effectively saved.

In addition, on the basis of the above scheme, errors in the above judgment result are avoided, and in some embodiments, the following improvements are provided: in step S203, before determining that the subcooling expansion valve and the heating expansion valve are reversely connected, when it is determined that the refrigerant does not effectively exchange heat at the condenser in the heating mode, based on the control logic of the current mode, the subcooling expansion valve and the heating expansion valve are controlled in a switching manner, and after continuously operating for a first preset time, whether the refrigerant effectively exchanges heat at the condenser is determined again;

correspondingly, in step S203, determining that the subcooling expansion valve and the heating expansion valve are reversely connected specifically includes: and if the effective heat exchange of the refrigerant at the condenser is determined after the judgment is carried out again, the supercooling expansion valve and the heating expansion valve are determined to be reversely connected.

Specifically, as described above, the reason that the refrigerant does not effectively exchange heat at the condenser may also be that a pipeline between the subcooler and the condenser is blocked, and in order to avoid misjudging such abnormality as the expansion valve being reversely connected, therefore, when it is preliminarily determined that the refrigerant does not effectively exchange heat at the condenser, the subcooling expansion valve and the heating expansion valve may be exchanged and controlled, and after the refrigerant is continuously operated for the first preset time, it may be determined whether the unit is normally recovered, and if the unit is normally recovered (the refrigerant effectively exchanges heat at the condenser), it may be determined that the subcooling expansion valve and the heating expansion valve are actually reversely connected. The switching control of the supercooling expansion valve and the heating expansion valve means that an instruction for adjusting the opening degree of the supercooling expansion valve is transmitted to the heating expansion valve, and an instruction for adjusting the opening degree of the heating expansion valve is transmitted to the supercooling expansion valve. In addition, after the two expansion valves are exchanged and controlled, the continuous operation for the first preset time is to ensure that the unit enters a stable operation state, so that misjudgment is avoided.

Further, after the two expansion valves are controlled by the exchange, the method for judging whether the unit is normal or not may include: and judging that the difference value between the ambient temperature and the temperature on the outlet side of the condenser is greater than or equal to an eleventh preset temperature, and if the judgment result is yes, determining that the unit recovers to be normal, wherein the value of the eleventh preset temperature is greater than the first preset temperature. That is to say, when the temperature of the outlet side of the condenser is obviously lower than the ambient temperature, it is indicated that the refrigerant passes through the heating expansion valve and then is throttled to reduce the temperature, that is, the refrigerant exchanges heat effectively in the condenser, so that the temperature is obviously reduced.

In addition, on the basis of the foregoing scheme, in another embodiment, the determining method further includes:

if the opening degree of the supercooling expansion valve is larger than zero, judging whether the absolute value of the difference value between the opening degree of the heating expansion valve and the opening degree of the supercooling expansion valve is larger than or equal to a first preset opening degree or not; if the absolute value of the difference value between the opening degree of the heating expansion valve and the opening degree of the supercooling expansion valve is greater than or equal to the first preset opening degree, and the opening degree of the heating expansion valve is greater than the opening degree of the supercooling expansion valve, judging whether the opening degree of the heating expansion valve is smaller than the opening degree to be opened or not based on a second preset judgment condition; and if the opening degree of the heating expansion valve is smaller than the opening degree to be opened, controlling the opening degree of the supercooling expansion valve to be equal to zero and controlling the opening degree of the heating expansion valve to be equal to a second preset opening degree, and after continuously operating for a second preset time, judging whether the refrigerant is subjected to effective heat exchange at the condenser based on the first preset judgment condition again.

Specifically, the opening degree of the subcooling expansion valve is greater than zero, that is, the subcooling expansion valve is not completely closed, and under this operating mode, the refrigerant that gets into the outdoor unit from the indoor set will not all get into the condenser after passing through the heating expansion valve, therefore, can not accurately judge whether the expansion valve joins conversely through the above-mentioned first preset judgment condition, and based on this, this embodiment judges whether the expansion valve joins conversely through other modes, specifically is: firstly, judging whether the absolute value of the difference value between the opening degree of the heating expansion valve and the opening degree of the supercooling expansion valve is greater than or equal to a first preset opening degree, namely judging whether the difference between the opening degree of the heating expansion valve and the opening degree of the supercooling expansion valve is larger; when the absolute value is greater than or equal to the first preset opening degree, the difference between the opening degrees of the two expansion valves is larger, and most of the refrigerant entering the outdoor unit passes through the expansion valve with the larger opening degree, so that under the working condition, if the two expansion valves are in reverse connection abnormity, the unit operation parameters (such as temperature parameters) are obviously different from those under normal conditions, and therefore whether the expansion valves are in reverse connection or not can be judged necessarily; further, the difference between the opening degrees of the two expansion valves is largely divided into two cases, that is, the opening degree of the heating expansion valve is larger than the opening degree of the supercooling expansion valve, or the opening degree of the heating expansion valve is smaller than the opening degree of the supercooling expansion valve, which will be described below.

For the case that the opening degree of the heating expansion valve is greater than the opening degree of the subcooling expansion valve, in this embodiment, based on a second preset determination condition, it is determined whether the opening degree of the heating expansion valve is smaller than the opening degree to be opened, and if the opening degree of the heating expansion valve is smaller than the opening degree to be opened, it indicates that the heating expansion valve and the subcooling expansion valve may be connected in reverse (i.e., it indicates that the heating expansion valve having a larger opening degree is a smaller one, but the actual opening degree is smaller), so in this embodiment, to verify whether the determination is correct, the opening degree of the subcooling expansion valve is controlled to be equal to zero and the opening degree of the heating expansion valve is controlled to be equal to the second preset opening degree, and after continuously operating for a second preset time (the continuously operating second preset time is also to ensure that the unit enters a stable state, hereinafter, the control unit continuously operates for a, that is, the opening degrees of the subcooling expansion valve and the heating expansion valve are reset so that the opening degrees of the subcooling expansion valve and the heating expansion valve satisfy the conditions for executing the step S202 and the subsequent steps, and thus whether the subcooling expansion valve and the heating expansion valve are reversely connected or not is judged again according to the corresponding conditions. The opening degree of the heating expansion valve refers to the opening degree corresponding to the heating expansion valve when the unit is normal (when the expansion valve is not reversely connected) under the current working condition, and the opening degree is calculated by the controller according to various parameters.

Further, as a possible implementation manner, the determining whether the opening degree of the heating expansion valve is smaller than the opening degree to be opened based on the second preset determination condition specifically includes: and if the difference between the ambient temperature and the temperature of the low pressure side of the compressor is greater than or equal to a fourth preset temperature and/or the difference between the temperature of the inlet side of the gas-liquid separator and the temperature of the low pressure side of the compressor is greater than or equal to a fifth preset temperature, determining that the opening degree of the heating expansion valve is smaller than the opening degree to be opened.

That is, when the difference between the ambient temperature and the temperature of the low-pressure side of the compressor is greater than or equal to the fourth preset temperature, it indicates that the low pressure in the environment is relatively low, which indicates that a large amount of refrigerant in the inlet pipe of the gas-liquid separator is not evaporated by the condenser, and directly enters the gas-liquid separator, and a small amount of gaseous refrigerant causes the low pressure detected by the low-pressure sensor to be relatively low, because the actual opening degree of the heating expansion valve is obviously smaller than the opening degree, a large amount of refrigerant is not evaporated by the condenser, and is directly bypassed into the gas-liquid separator; when the difference between the inlet side temperature of the gas-liquid separator and the low-pressure side temperature of the compressor is greater than or equal to the fifth preset temperature, the inlet side temperature of the gas-liquid separator is obviously greater than the low-pressure side temperature of the compressor, so that the refrigerant is fully evaporated in the condenser, and sufficient suction superheat degree is obtained, possibly because the actual opening degree of the heating expansion valve is obviously smaller than the opening degree to be opened at the moment, the refrigerant flowing through the condenser is less.

Further, in some embodiments, the method further comprises: if the absolute value of the difference value between the opening degree of the heating expansion valve and the opening degree of the supercooling expansion valve is greater than or equal to the first preset opening degree, and the opening degree of the heating expansion valve is smaller than the opening degree of the supercooling expansion valve, judging whether the opening degree of the heating expansion valve is greater than the opening degree to be opened or not based on a third preset judgment condition; and if the opening degree of the heating expansion valve is larger than the opening degree to be opened, controlling the opening degree of the supercooling expansion valve to be equal to zero and controlling the opening degree of the heating expansion valve to be equal to a third preset opening degree, and after continuously running for a second preset time, judging whether the refrigerant is subjected to effective heat exchange at the condenser based on the first preset judgment condition again.

That is, in the embodiment, in the case where the opening degree of the heating expansion valve is different from that of the subcooling expansion valve greatly, and the opening degree of the heating expansion valve is greater than that of the subcooling expansion valve, based on the third preset determination condition, it is determined whether the opening degree of the heating expansion valve is greater than that to be opened, and if the opening degree of the heating expansion valve is greater than that to be opened, it is indicated that the heating expansion valve and the subcooling expansion valve may be reversely connected (i.e., it is indicated that the actual opening degree is greater at the heating expansion valve having a smaller opening degree, on the contrary), therefore, in order to verify whether the determination is correct, in this embodiment, to control the opening degree of the heating expansion valve to be equal to zero and the opening degree of the heating expansion valve to be equal to the third preset opening degree, and after continuously operating for the second preset time, based on the first preset, the opening degrees of the two valves are made to satisfy the conditions for executing step S202 and the subsequent steps, and whether the subcooling expansion valve and the heating expansion valve are connected reversely is determined again according to the corresponding conditions. The third preset opening degree may be the same as or different from the second preset opening degree.

As a possible implementation manner, the determining whether the opening degree of the heating expansion valve is greater than the opening degree to be opened based on the third preset determination condition specifically includes: and if the difference between the ambient temperature and the temperature of the low pressure side of the compressor is less than or equal to a sixth preset temperature and/or the difference between the temperature of the inlet side of the gas-liquid separator and the temperature of the low pressure side of the compressor is less than or equal to a seventh preset temperature, determining that the opening degree of the heating expansion valve is greater than the opening degree to be opened.

That is, when the difference between the ambient temperature and the temperature of the low-pressure side of the compressor is less than or equal to the sixth preset temperature, it indicates that the low pressure in the environment is higher, which indicates that a large amount of refrigerant in the inlet pipe of the gas-liquid separator is evaporated by the condenser, the gaseous refrigerant is more, and the low pressure detected by the low-pressure sensor is higher, because the actual opening degree of the heating expansion valve is obviously greater than the opening degree to be opened, the large amount of refrigerant is evaporated by the condenser, and the gaseous refrigerant is more; when the difference between the temperature of the inlet side of the gas-liquid separator and the temperature of the low-pressure side of the compressor is less than or equal to the seventh preset temperature, the suction superheat degree is relatively low or no suction superheat degree is indicated, and the refrigerant is not completely evaporated in the condenser, possibly because the actual opening degree of the heating expansion valve is obviously greater than the opening degree to be opened at the moment, so that the refrigerant flowing through the condenser is relatively large.

In addition, the present application also provides a corresponding determination method in the cooling mode, referring to fig. 3, where fig. 3 is a schematic flow chart of another determination method for determining the reverse connection of the expansion valve provided in the present application; as shown in fig. 3, the method at least comprises the following steps:

s301: in the refrigeration mode, judging whether the opening degree of the supercooling expansion valve is larger than zero;

specifically, in the cooling mode, if the expansion valve is normally connected, the heating expansion valve must be fully opened, and the subcooling expansion valve may be fully closed or opened to a certain opening degree. Therefore, the present embodiment first detects whether the opening degree of the subcooling expansion valve is larger than zero, in order to determine whether the two expansion valves are reversely connected according to the corresponding situation.

S302: if the opening degree of the supercooling expansion valve is not larger than zero, judging whether the refrigerant effectively exchanges heat at the condenser or not based on a fourth preset judgment condition;

specifically, if the opening degree of the subcooling expansion valve is not greater than zero, that is, the subcooling expansion valve is completely closed, in this case, if the two expansion valves are not reversely connected, all the refrigerant entering the outdoor unit enters the condenser through the heating expansion valve to perform heat exchange (heat release in the cooling mode), and therefore, in this embodiment, it is determined whether the two expansion valves are reversely connected by determining whether the refrigerant is effectively heat exchanged at the condenser.

Further, as a feasible implementation manner, based on a fourth preset determination condition, determining whether the refrigerant is subjected to effective heat exchange at the condenser specifically may include: and if the temperature of the high-pressure side of the compressor is continuously higher than or equal to the eighth preset temperature within the third preset time and/or the absolute value of the difference value between the ambient temperature and the temperature of the liquid outlet side of the subcooler is lower than or equal to the ninth preset temperature, determining that the refrigerant does not effectively exchange heat at the condenser.

When the temperature of the high-pressure side of the compressor is continuously greater than or equal to the eighth preset temperature within the third preset time, the high pressure in the environment is higher, which indicates that the refrigerant in the condenser is not effectively radiated, and the reason may be that the outlet pipe of the condenser is blocked or the opening of the heating expansion valve is smaller; and when the absolute value of the difference value between the ambient temperature and the temperature of the liquid outlet side of the subcooler is less than or equal to the ninth preset temperature, the ambient temperature is similar to the temperature of the liquid outlet side of the subcooler, and the reason that no refrigerant passes through a pipeline from the condenser to the subcooler is probably that the pipeline is blocked or the heating expansion valve is not actually opened.

S303: and if the refrigerant does not effectively exchange heat at the condenser in the refrigeration mode, determining that the supercooling expansion valve and the heating expansion valve are reversely connected.

Through the scheme, the unit can also automatically judge whether the supercooling expansion valve and the heating expansion valve are reversely connected in the cooling mode, so that the unit can be prevented from being broken down or damaged due to the reverse connection of the expansion valve based on the judgment, the judgment process does not need manual participation, and the labor cost can be effectively saved.

if the opening degree of the supercooling expansion valve is larger than zero, judging whether the difference value between the opening degree of the heating expansion valve and the opening degree of the supercooling expansion valve is larger than or equal to a fourth preset opening degree; if the difference value between the opening degree of the heating expansion valve and the opening degree of the supercooling expansion valve is larger than or equal to a fourth preset opening degree, judging whether the difference value between the temperature of the outlet side of the gas-liquid separator and the temperature of the low pressure side of the compressor is continuously smaller than or equal to a tenth preset temperature within continuous fourth preset time; and if the difference value is continuously less than or equal to a tenth preset temperature within a continuous fourth preset time, controlling the opening degree of the supercooling expansion valve to be equal to zero and the opening degree of the heating expansion valve to be equal to a fifth preset opening degree, and after continuously running for a fifth preset time, judging whether the refrigerant is subjected to effective heat exchange at the condenser based on the fourth preset judgment condition again.

Specifically, the opening degree of the subcooling expansion valve is greater than zero, that is, the subcooling expansion valve is not completely closed, and under this operating mode, the refrigerant flowing out of the heating expansion valve can not all directly enter the subcooler (part of the refrigerant can pass through the subcooling expansion valve first and then enter the subcooler), so whether the expansion valve is reversely connected can not be accurately judged through the above-mentioned fourth preset judgment condition, and based on this, the embodiment judges whether the expansion valve is reversely connected through other modes, specifically is: judging whether the difference value between the opening degree of the heating expansion valve and the opening degree of the supercooling expansion valve is greater than or equal to a fourth preset opening degree, namely judging whether the opening degree of the heating expansion valve is obviously greater than the opening degree of the supercooling expansion valve (because the heating expansion valve is fully opened in a refrigeration mode, the condition that the opening degree of the heating expansion valve is smaller than the opening degree of the supercooling expansion valve does not need to be considered); when the opening difference value is greater than or equal to a fourth preset opening, the opening difference value indicates that the opening degree of the supercooling expansion valve is smaller, most of the refrigerant flowing out of the heating expansion valve can not flow through the supercooling expansion valve, and therefore, under the working condition, if the two expansion valves are in reverse connection abnormity, unit operation parameters (such as temperature parameters) are obviously different from those under normal conditions, and whether the expansion valves are in reverse connection or not can be judged necessarily;

in view of this situation, in this embodiment, when the difference between the opening degree of the heating expansion valve and the opening degree of the subcooling expansion valve is greater than or equal to the fourth preset opening degree, it is determined whether the difference between the outlet side temperature of the gas-liquid separator and the low-pressure side temperature of the compressor is continuously less than or equal to the tenth preset temperature within the continuous fourth preset time, if so, it indicates that the outlet side temperature (outlet pipe temperature) of the gas-liquid separator is low relative to the low-pressure side temperature of the compressor, a large amount of liquid refrigerant may bypass into the gas-liquid separator, that is, the actual opening degree of the subcooling expansion valve is large and does not match with a normal condition. In order to further verify whether the determination is correct, in this embodiment, the opening degree of the subcooling expansion valve is further controlled to be equal to zero, and the opening degree of the heating expansion valve is controlled to be equal to a fifth preset opening degree, and after the subcooling expansion valve is continuously operated for a fifth preset time, whether the refrigerant is in effective heat exchange at the condenser is determined based on the fourth preset determination condition again, that is, the opening degrees of the subcooling expansion valve and the heating expansion valve are reset, so that the opening degrees of the subcooling expansion valve and the heating expansion valve meet the condition of the execution step S302 and the subsequent steps, and whether the subcooling expansion valve and the heating expansion valve are reversely connected.

When the opening difference value is smaller than the fourth preset opening, the opening difference value indicates that the opening degree of the supercooling expansion valve is larger (close to full opening), at the moment, the refrigerant quantity passing through the two expansion valves is closer, so that whether the two expansion valves are reversely connected is difficult to accurately judge, and because the two expansion valves are consistent in structure, the operation of the unit is not obviously influenced even if the two expansion valves are reversely connected, so that the operation of the unit is controlled according to normal control logic.

In addition, when the unit parameters do not meet the condition that the supercooling expansion valve and the heating expansion valve are reversely connected, the control is continued according to the normal control logic.

Further, in some embodiments, after determining that the subcooling expansion valve and the heating expansion valve are reverse connected, the method further comprises: and controlling the unit to stop and reporting the reverse connection fault of the expansion valve. That is, when it is determined that the subcooling expansion valve and the heating expansion valve are reversely connected, the unit is stopped and a maintenance person is notified to perform inspection and maintenance.

In yet other embodiments, after determining that the subcooling expansion valve and the heating expansion valve are reverse-connected, the method further comprises: and exchanging and controlling the supercooling expansion valve and the heating expansion valve based on the control logic of the current mode until the unit is powered off. That is, after the supercooling expansion valve and the heating expansion valve are determined to be reversely connected, the unit is not controlled to stop, but the supercooling expansion valve and the heating expansion valve are controlled to be exchanged, so that the unit continues to normally operate, and the reliability of the unit is improved.

In addition, in order to avoid the occurrence of erroneous determination, the determining whether the opening degree of the subcooling expansion valve is larger than zero specifically includes: and after the unit is at least electrified and operated for the sixth preset time, judging whether the opening degree of the supercooling expansion valve is larger than zero or not. That is, in both the cooling mode and the heating mode, it is preferable that the operation is restarted for a certain time after the power of the unit is cut off, and after the unit enters a steady state, the above-described steps of determining whether the expansion valves are reversely connected are started.

In addition, based on the same inventive concept, the present application also provides a device for determining reverse connection of an expansion valve, corresponding to the method of the above embodiment. The means are software and/or hardware based functional modules in the device performing the above method.

Referring to fig. 4, fig. 4 is a schematic structural diagram of a device for determining reverse connection of an expansion valve according to an embodiment of the present application. As shown in fig. 4, the apparatus includes:

a first judging module 41, configured to judge whether an opening degree of the subcooling expansion valve is greater than zero in the heating mode;

the second judgment module 42 is configured to, if the opening degree of the subcooling expansion valve is not greater than zero, judge whether the refrigerant is in effective heat exchange at the condenser based on a first preset judgment condition;

and the determining module 43 is configured to determine that the subcooling expansion valve and the heating expansion valve are reversely connected if the refrigerant does not effectively exchange heat at the condenser in the heating mode.

Optionally, when determining whether the refrigerant is subjected to effective heat exchange at the condenser based on a first preset determination condition, the second determination module 42 is specifically configured to:

Optionally, the second determining module 42 is further configured to: when the refrigerant is determined not to be subjected to effective heat exchange at the condenser in the heating mode, based on the control logic of the current mode, the supercooling expansion valve and the heating expansion valve are exchanged and controlled, and after the refrigerant is continuously operated for the first preset time, whether the refrigerant is subjected to effective heat exchange at the condenser is judged again;

correspondingly, the determining module 43 is configured to:

Optionally, the apparatus further includes a third determining module, configured to:

Optionally, the third determining module is further configured to:

Optionally, the third determining module is specifically configured to, when determining whether the opening degree of the heating expansion valve is smaller than the opening degree to be opened based on a second preset determining condition:

Optionally, the third determining module is specifically configured to, when determining whether the opening degree of the heating expansion valve is greater than the opening degree to be opened based on a third preset determining condition:

Optionally, the second determining module is specifically configured to, when determining whether the refrigerant is in effective heat exchange at the condenser based on a fourth preset determining condition:

Optionally, the third determining module is further configured to:

Optionally, the apparatus further comprises:

and the fault processing module is used for controlling the machine set to stop and reporting the reverse connection fault of the expansion valve.

Optionally, the fault handling module is further configured to:

Optionally, the first determining module is specifically configured to, when determining whether the opening degree of the subcooling expansion valve is greater than zero:

The specific implementation method of the steps executed by the functional modules of the apparatus may refer to the corresponding content of the foregoing method embodiments, and will not be described in detail here.

In addition, referring to fig. 5, an embodiment of the present application further provides a controller of an air conditioner, including:

a memory 51 and a processor 52 connected to the memory 51; the memory 51 is used for storing a program for implementing at least the method described in the foregoing embodiments; the processor 52 is used to call and execute the program stored in the memory 51.

When the controller of the air conditioner is applied to the air conditioner, the corresponding judgment method can be realized. Moreover, the specific implementation method of the steps executed by the above program may refer to the corresponding content of the foregoing method embodiments, and will not be described in detail here.

By the scheme, whether the opening degree of the supercooling expansion valve is larger than zero or not can be automatically judged; if the opening degree of the supercooling expansion valve is not larger than zero, judging whether the refrigerant is subjected to effective heat exchange at the condenser or not based on a preset judgment condition; if the refrigerant does not exchange heat effectively at the condenser, determining that the supercooling expansion valve and the heating expansion valve are reversely connected; when the opening degree of the supercooling expansion valve is larger than zero, the supercooling expansion valve and the heating expansion valve are judged to be reversely connected through other conditions, so that the unit can be prevented from being broken or damaged due to the reverse connection of the expansion valve on the basis, manual participation is not needed in the judging process, and the labor cost can be effectively saved.

It is understood that the same or similar parts in the above embodiments may be mutually referred to, and the same or similar parts in other embodiments may be referred to for the content which is not described in detail in some embodiments.

It should be noted that, in the description of the present application, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Further, in the description of the present application, the meaning of "a plurality" means at least two unless otherwise specified.

Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps of the process, and the scope of the preferred embodiments of the present application includes other implementations in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the present application.

It should be understood that portions of the present application may be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or combination of the following techniques, which are known in the art, may be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like.

It will be understood by those skilled in the art that all or part of the steps carried by the method for implementing the above embodiments may be implemented by hardware related to instructions of a program, which may be stored in a computer readable storage medium, and when the program is executed, the program includes one or a combination of the steps of the method embodiments.

In addition, functional units in the embodiments of the present application may be integrated into one processing module, or each unit may exist alone physically, or two or more units are integrated into one module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. The integrated module, if implemented in the form of a software functional module and sold or used as a stand-alone product, may also be stored in a computer readable storage medium.

The storage medium mentioned above may be a read-only memory, a magnetic or optical disk, etc.

In the description herein, reference to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present application, and that variations, modifications, substitutions and alterations may be made to the above embodiments by those of ordinary skill in the art within the scope of the present application.

Claims

1. A method for judging reverse connection of an expansion valve is characterized by comprising the following steps:

2. The method of claim 1, wherein the determining whether the refrigerant is effectively heat-exchanged at the condenser based on the first predetermined determination condition comprises:

3. The method of claim 1, wherein said determining that the subcooling expansion valve and the heating expansion valve are reversed, further comprises:

4. The method of claim 1, further comprising:

5. The method of claim 4, further comprising:

6. The method according to claim 4, wherein the determining whether the opening degree of the heating expansion valve is smaller than the opening degree to be opened based on the second preset determination condition includes:

7. The method according to claim 5, wherein the determining whether the opening degree of the heating expansion valve is greater than the opening degree to be opened based on a third preset determination condition includes:

8. The method of claim 1, further comprising:

9. The method of claim 8, wherein the determining whether the refrigerant exchanges heat effectively at the condenser based on a fourth predetermined determination condition comprises:

10. The method of claim 8, further comprising:

11. The method of any of claims 1-10, wherein determining that the subcooling expansion valve and the heating expansion valve are in reverse connection further comprises:

12. The method of any of claims 1-10, wherein determining that the subcooling expansion valve and the heating expansion valve are in reverse connection further comprises:

13. The method according to any one of claims 1 to 10, wherein the determining whether the opening degree of the subcooling expansion valve is greater than zero specifically comprises:

14. An expansion valve reverse connection judging device is characterized by comprising:

15. The apparatus of claim 14, wherein the first determining module is further configured to determine whether an opening degree of the subcooling expansion valve is greater than zero in the cooling mode;

16. A controller of an air conditioner, comprising:

a memory and a processor coupled to the memory;

the memory for storing a program for implementing at least the method of any one of claims 1-13;

17. An air conditioner characterized in that a controller of the air conditioner as claimed in claim 16 is provided.