CN113124541B

CN113124541B - Judgment method and device for reverse connection of expansion valve, controller and air conditioner

Info

Publication number: CN113124541B
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: 2024-01-23
Anticipated expiration: 2041-04-14
Also published as: CN113124541A

Abstract

The application relates to a judgment method and device for 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 ensured not to be failed or damaged due to reverse connection of the expansion valves based on the reverse connection, and the judging process does not need manual participation, so that the labor cost can be effectively saved.

Description

Judgment method and device for 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 judgment method and device for reverse connection of an expansion valve, a controller and an air conditioner.

Background

During development, production, and after-sales of air conditioning units, the electronic expansion valve (Electronic expansion valve, EXV) terminals may need to be disassembled.

And the terminal structures of the heating expansion valve and the supercooling expansion valve of part of the unit are consistent, the situation that the heating expansion valve and the supercooling expansion valve are reversely connected can occur in the process of disassembly and assembly, when the unit is operated under the situation, the unit fault is easy to be induced, and even if the unit is not in fault in a short period, the unit is damaged after long-term operation. In the prior art, no related detection method can automatically judge whether the heating expansion valve and the supercooling expansion valve are reversely connected except for manual confirmation.

Disclosure of Invention

The application provides a judgment method and device for reverse connection of an expansion valve, a controller and an air conditioner, and aims to solve the problem that whether a heating expansion valve and a supercooling expansion valve are in reverse connection 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:

judging whether the opening of the supercooling expansion valve is larger than zero or not in a heating mode;

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

if the refrigerant does not exchange heat effectively 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 the first preset determining condition, whether the refrigerant exchanges heat effectively at the condenser includes:

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

Optionally, the determining the reverse connection between the supercooling expansion valve and the heating expansion valve further includes:

when the refrigerant is determined to be not 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 controlled in a switching mode, and whether the refrigerant is subjected to effective heat exchange at the condenser is judged again after the first preset time is continuously operated;

the determining supercooling expansion valve and the heating expansion valve are reversely connected, and specifically comprises the following steps:

if the refrigerant is determined to exchange heat effectively at the condenser after the re-judgment, the supercooling expansion valve and the heating expansion valve are determined to be reversely connected.

Optionally, the method further comprises:

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

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

if the opening degree of the heating expansion valve is smaller than the opening degree of the opening, 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 running for a second preset time, judging whether the refrigerant exchanges heat effectively at the condenser or not based on the first preset judging condition again.

Optionally, the method further comprises:

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

if the opening degree of the heating expansion valve is larger than the opening degree of the opening, 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 exchanges heat effectively at the condenser or not based on the first preset judging condition again.

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

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

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

If the difference between the ambient temperature and the low-pressure side temperature of the compressor is smaller than or equal to a sixth preset temperature, and/or the difference between the inlet side temperature of the gas-liquid separator and the low-pressure side temperature of the compressor is smaller than or equal to a seventh preset temperature, determining that the opening of the heating expansion valve is larger than the opening.

Optionally, the method further comprises:

judging whether the opening of the supercooling expansion valve is larger than zero in a refrigerating mode;

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

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

Optionally, the determining whether the refrigerant exchanges heat effectively at the condenser based on the fourth preset determining condition includes:

if the temperature of the high-pressure side of the compressor is continuously higher than or equal to the eighth preset temperature in 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 exchange heat effectively at the condenser.

Optionally, the method further comprises:

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

If the difference between the opening of the heating expansion valve and the opening of the supercooling expansion valve is larger than or equal to a fourth preset opening, judging whether the difference 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 in a continuous fourth preset time;

if the difference is continuously smaller than or equal to the tenth preset temperature within the fourth preset time, controlling the opening of the supercooling expansion valve to be equal to zero and controlling the opening of the heating expansion valve to be equal to the fifth preset opening, and judging whether the refrigerant exchanges heat effectively at the condenser or not again based on the fourth preset judging condition after continuously running for the fifth preset time.

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

and based on the control logic of the current mode, the supercooling expansion valve and the heating expansion valve are controlled in a switching mode until the unit is powered off.

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

and after the unit is at least electrified and operated for a 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 judging module is used for judging whether the opening degree of the supercooling expansion valve is larger than zero or not under the heating mode;

the second judging module is used for judging whether the refrigerant exchanges heat effectively at the condenser or not based on the first preset judging condition if the opening degree of the supercooling expansion valve is not more 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 exchange heat effectively at the condenser in the heating mode.

Optionally, the first judging module is further configured to judge, in a refrigeration mode, whether the opening of the supercooling expansion valve is greater than zero;

the second judging module is further used for judging whether the refrigerant exchanges heat effectively at the condenser or not based on a fourth preset judging condition if the opening degree of the supercooling expansion valve is not more 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 exchange heat effectively at the condenser in the refrigeration mode.

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

a memory and a processor coupled to the memory;

the memory is configured to store a program at least for implementing the method according to any one of the first aspects;

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 in the third aspect.

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

in the technical scheme provided by the embodiment of the application, under a heating mode, whether the opening of the supercooling expansion valve is larger than zero can be automatically judged; if the opening of the supercooling expansion valve is not more than zero, judging whether the refrigerant exchanges heat effectively at the condenser or not based on a first preset judging condition; if the refrigerant does not exchange heat effectively at the condenser in the heating mode, the supercooling expansion valve and the heating expansion valve are determined to be reversely connected. So set up, through the judgement condition that sets up in advance, whether the unit can automatic judgement heating expansion valve and supercooling expansion valve are reverse to can guarantee based on this that the unit can not be because of expansion valve reverse connection and break down or damage, and judge the process and need not artifical the participation, can effectively practice thrift the cost of labor.

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 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 application;

fig. 2 is a flow chart of a method for determining reverse connection of an expansion valve according to an embodiment of the present application;

fig. 3 is a flow chart of another method for determining reverse connection of an expansion valve according to an embodiment of the present application;

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;

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 exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The implementations described in the following exemplary examples are not representative of all implementations consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with some aspects of the present application as detailed in the accompanying claims.

In order to solve the problems set forth in the background art, the present application provides a method for automatically detecting and judging whether a heating expansion valve and a supercooling expansion valve are reversely connected.

In order to make the technical scheme of the application easier to understand, first, the structure and operation principle of the air conditioning unit to which the technical scheme of the application can be applied will be described. 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 comprises an indoor unit and an outdoor unit, wherein the outdoor unit mainly comprises a compressor, a four-way valve, a condenser, a heating expansion valve (namely heating EXV in fig. 1), a supercooling expansion valve (namely supercooling EXV in fig. 1), a supercooling device, a gas-liquid separator (short for gas separation), an outdoor unit fan, a pipeline for connecting all components, and a plurality of pressure sensors and temperature sensors (temperature sensing bags) arranged on the pipeline or the components; the indoor unit mainly comprises an evaporator, an indoor unit expansion valve (namely an indoor unit EXV in the figure 1), an indoor unit fan and pipelines for connecting the components.

When heating, the low-pressure low-temperature refrigerant is changed into a high-temperature high-pressure refrigerant after passing through the compressor, then enters the indoor unit through the four-way valve, and enters the outdoor unit after radiating and condensing in the evaporator of the indoor unit under the air supply effect of the fan of the indoor unit. The refrigerant flows through the heating expansion valve in the outdoor unit for throttling and reducing pressure, is quickly evaporated in the condenser under the air supply effect of the fan of the outdoor unit, then enters the gas-liquid separator through the four-way valve, and finally enters the compressor. As can be seen from fig. 1, when the refrigerant enters the outdoor unit, the refrigerant may be throttled by the supercooling expansion valve before passing through the heating expansion valve, and then enters the gas-liquid separator. The refrigerant flowing through the supercooling expansion valve and the refrigerant of the heating expansion valve exchange heat in the supercooler.

During refrigeration, the low-pressure low-temperature refrigerant is changed into a high-temperature high-pressure refrigerant after passing through the compressor, then enters the condenser through the four-way valve, dissipates heat and condenses under the air supply action of the outer machine fan, then enters the indoor machine, is throttled and depressurized through the inner machine expansion valve, is evaporated in the evaporator under the air supply action of the inner machine fan, then enters the outdoor machine, enters the air component through the four-way valve, and then enters 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 flow through the supercooling expansion valve to be throttled, and then enter the gas. The refrigerant flowing through the supercooling expansion valve exchanges heat with the refrigerant entering the indoor unit in the supercooler.

The pressure sensor arranged in the outdoor unit comprises a low pressure sensor and a high pressure sensor, wherein the low pressure sensor is arranged on the low pressure side (inlet side) of the compressor and is used for detecting the low pressure of the unit; the high pressure sensor is arranged at the high pressure side (outlet side) of the compressor and is used for detecting the high pressure of the unit. Further, the bulb includes a gas-separation-tube bulb, an environmental bulb, an exhaust bulb, a supercooled-gas-outlet bulb, a supercooled-liquid-outlet bulb, and a defrosting bulb (condenser-outlet-tube bulb) for detecting a gas-liquid separator inlet side temperature, a gas-liquid separator outlet side temperature, an environmental temperature, a compressor high-pressure side temperature, a subcooler gas outlet side temperature, a subcooler liquid outlet side temperature, and a defrosting temperature (condenser outlet side temperature), respectively. 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 supercooling expansion valve are reversely connected after being disassembled, the embodiment provides a method for judging whether the expansion valves are reversely connected. Referring to fig. 2, fig. 2 is a flow chart of a method for determining reverse connection of an expansion valve according to an embodiment of the present application.

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

s201: judging whether the opening of the supercooling expansion valve is larger than zero or not in a heating mode;

specifically, in the heating mode, as described in the above principle, if the expansion valve is connected normally, the heating expansion valve must be opened, and the supercooling expansion valve may be completely closed, or may be opened by a certain opening degree (depending on the operation parameters of the unit under the current working condition). Therefore, the present embodiment first detects whether the opening degree of the supercooling expansion valve is greater than zero, in order to determine whether two expansion valves (in this application, "two expansion valves" refer to the supercooling expansion valve and the heating expansion valve, and the following are the same) are reversely connected according to the corresponding conditions.

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

specifically, if the opening of the supercooling expansion valve is not greater than zero, that is, the supercooling expansion valve is completely closed, in this case, if the two expansion valves are not in reverse connection, all the refrigerant entering the outdoor unit enters the condenser to perform heat exchange (heat absorption in the heating mode) after passing through the heating expansion valve, so in this embodiment, whether the two expansion valves are in reverse connection is determined by judging whether the refrigerant is in effective heat exchange at the condenser, wherein the effective heat exchange of the refrigerant at the condenser means that a sufficient amount (the amount capable of meeting the current heating requirement) of the refrigerant is in sufficient heat exchange at the condenser.

Further, as a possible implementation manner, based on a first preset judging condition, judging whether the refrigerant is effective for heat exchange at the condenser may specifically include:

That is, the refrigerant may be considered not to be effectively heat exchanged at the condenser when one or more of the following three conditions occur: (1) the absolute value of the difference between the temperature at the outlet side of the condenser and the ambient temperature is less than or equal to a first preset temperature; (2) the difference between the low pressure side temperature of the compressor and the ambient temperature is less than or equal to a second preset temperature; (3) the difference 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 condition (1) indicates that the temperature of the outlet side of the condenser (defrosting temperature) is close to the ambient temperature, which indicates that the refrigerant does not pass through the condenser, and the reason may be that a pipeline between the subcooler and the condenser is blocked, or that 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 condition (2) indicates that the low pressure of the unit in the environment is lower, the reason may be that the refrigerant in the inlet pipe (inlet side) of the gas-liquid separator does not absorb heat effectively by the condenser, the gaseous refrigerant is less, the low pressure detected by the low pressure sensor is lower, and the reason for that the refrigerant does not absorb heat effectively by the condenser may be that the heating expansion valve is not opened; the case (3) indicates that the temperature of the outlet side of the gas-liquid separator is significantly lower than the temperature of the inlet side of the gas-liquid separator, which means that the refrigerant in the gas-liquid separator continuously evaporates and absorbs heat, so that the temperature of the outlet side of the gas-liquid separator is significantly lower than the temperature of the inlet side of the gas-liquid separator, and the reason why a large amount of refrigerant enters the gas-liquid separator may be that the heating expansion valve is not opened.

That is, when the reverse connection abnormality occurs in the heating expansion valve and the supercooling expansion valve, since the control of both the heating expansion valve and the supercooling expansion valve is still in the normal control mode, the open and close states of the heating expansion valve and the supercooling expansion valve are exactly opposite to those of the normal case, specifically, the heating expansion valve should be opened in the normal case, the supercooling expansion valve is closed, and the heating expansion valve is closed and the supercooling expansion valve is opened in the abnormal case, and therefore, in the 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 supercooling expansion valve, thereby causing an abnormal case that the refrigerant does not effectively exchange heat at the condenser.

In order to improve the accuracy of the determination, when determining whether the refrigerant is effectively heat-exchanged at the condenser based on the first preset determination condition, it is preferable that the refrigerant is not effectively heat-exchanged at the condenser when the above three conditions (1), (2) and (3) are all present. Of course, it should be understood that, in the present embodiment, the three cases (1), (2) and (3) corresponding to the first preset determination condition are only exemplary, and other determination conditions may be used to determine whether the refrigerant is effectively exchanging heat at the condenser in practical application, which is not limited. And, similarly, the possible implementation methods of the second preset determination condition, the third preset determination condition, and the like given below are also exemplary and should not be taken as limiting the present application.

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

Through the scheme, in a heating mode, the unit can automatically judge whether the opening of the supercooling expansion valve is larger than zero; if the opening of the supercooling expansion valve is not more than zero, judging whether the refrigerant exchanges heat effectively at the condenser or not based on a first preset judging condition; if the refrigerant does not exchange heat effectively at the condenser in the heating mode, the supercooling expansion valve and the heating expansion valve are determined to be reversely connected. So set up, through the judgement condition that sets up in advance, whether the unit can automatic judgement heating expansion valve and supercooling expansion valve are reverse to can guarantee based on this that the unit can not be because of expansion valve reverse connection and break down or damage, and judge the process and need not artifical the participation, can effectively practice thrift the cost of labor.

In addition, on the basis of the above scheme, the error of the above judgment result is avoided, and in some embodiments, the following improvements are further provided: in step S203, before determining that the supercooling expansion valve and the heating expansion valve are reversely connected, when determining that the refrigerant is not subjected to effective heat exchange at the condenser in the heating mode, based on the control logic of the current mode, controlling the supercooling expansion valve and the heating expansion valve in a switching mode, and after continuously operating for a first preset time, judging whether the refrigerant is subjected to effective heat exchange at the condenser again;

Correspondingly, in step S203, determining that the supercooling expansion valve and the heating expansion valve are reversely connected specifically includes: if the refrigerant is determined to exchange heat effectively at the condenser after the re-judgment, the supercooling expansion valve and the heating expansion valve are determined to be reversely connected.

Specifically, as described above, the reason why the refrigerant does not exchange heat effectively at the condenser may be that the pipe between the subcooler and the condenser is blocked, so as to avoid misjudging such abnormality as reverse connection of the expansion valve, when the refrigerant is determined to be not exchanging heat effectively at the condenser, the subcooling expansion valve and the heating expansion valve may be controlled to be exchanged first, and after the first preset time of operation, whether the unit is recovered to be normal is determined, if the unit is recovered to be normal (the refrigerant exchanges heat effectively at the condenser), it may be determined that the subcooling expansion valve and the heating expansion valve are indeed reverse connected. The modulation control of the supercooling expansion valve and the heating expansion valve means that a command for adjusting the opening degree of the supercooling expansion valve is transmitted to the heating expansion valve, and a command 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 controlled in a switching mode, the first preset time is continuously operated to ensure that the unit enters a stable operation state, and misjudgment is avoided.

Further, after the two expansion valves are controlled in a switching manner, the method for judging whether the unit is recovered to be normal may include: and judging that the difference value between the ambient temperature and the temperature of the outlet side of the condenser is larger than or equal to an eleventh preset temperature, and if the judgment result is yes, determining that the unit is recovered to be normal, wherein the value of the eleventh preset temperature is larger than the first preset temperature. That is, when the temperature of the outlet side of the condenser is obviously lower than the ambient temperature, the refrigerant is throttled and cooled after passing through the heating expansion valve, namely the refrigerant effectively exchanges heat in the condenser, so that the temperature is obviously reduced.

In addition, in other embodiments, the method further includes:

if the opening of the supercooling expansion valve is larger than zero, judging whether the absolute value of the difference value between the opening of the heating expansion valve and the opening of the supercooling expansion valve is larger than or equal to a first preset opening; if the absolute value of the difference between the opening of the heating expansion valve and the opening of the supercooling expansion valve is larger than or equal to the first preset opening, and the opening of the heating expansion valve is larger than the opening of the supercooling expansion valve, judging whether the opening of the heating expansion valve is smaller than the opening or not based on a second preset judging condition; if the opening degree of the heating expansion valve is smaller than the opening degree of the opening, 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 running for a second preset time, judging whether the refrigerant exchanges heat effectively at the condenser or not based on the first preset judging condition again.

Specifically, the opening of the supercooling expansion valve is greater than zero, that is, the supercooling expansion valve is not completely closed, under this condition, the refrigerant entering the outdoor unit from the indoor unit does not enter the condenser after all passing through the heating expansion valve, so whether the expansion valve is reversely connected cannot be accurately judged through the first preset judgment condition, and based on this, whether the expansion valve is reversely connected is judged through other modes, specifically: firstly, judging whether the absolute value of the difference between the opening of the heating expansion valve and the opening of the supercooling expansion valve is larger than or equal to a first preset opening, namely judging whether the difference between the opening of the heating expansion valve and the opening of the supercooling expansion valve is larger; when the absolute value is larger than or equal to the first preset opening, the difference of the opening of the two expansion valves is larger, and most of the refrigerant entering the outdoor unit passes through the expansion valve with larger opening at the moment, so that under the working condition, if the two expansion valves are in reverse connection abnormality, the unit operation parameters (such as temperature parameters) are obviously different from those of the unit operation parameters under normal conditions, and therefore, whether the expansion valves are in reverse connection or not can be judged; further, the difference in opening degree 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, and these two cases will be described below, respectively.

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 of the supercooling expansion valve, if the opening degree of the heating expansion valve is smaller than the opening degree, it is indicated that the heating expansion valve and the supercooling expansion valve may be reversely connected (that is, the opening degree of the heating expansion valve where the opening degree is supposed to be larger is indicated that the actual opening degree is smaller instead), so in this embodiment, in order to verify whether the determination is correct, the opening degree of the supercooling expansion valve is controlled to be equal to zero and the opening degree of the heating expansion valve is controlled to be equal to a second preset opening degree, and after the second preset operation time (the second preset operation time is also for ensuring that the unit enters a steady state, and then the unit is controlled to continuously operate for a period of time under a specific condition), based on the first preset determination condition again, it is determined whether the refrigerant is effectively heat exchanged at the condenser, that is reset to set the opening degree of the supercooling expansion valve and the heating expansion valve is made to satisfy the conditions of executing step S202 and the subsequent steps, so as to re-determine whether the supercooling expansion valve and the reverse heating expansion valve are reversely connected 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, the opening degree is calculated by the controller according to various parameters, and the opening degree is not improved, so that the calculation process is not described.

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

That is, when the difference between the ambient temperature and the low pressure side temperature of the compressor is greater than or equal to the fourth preset temperature, which indicates that the low pressure in the environment is low, which means that a large amount of refrigerant in the inlet pipe of the gas-liquid separator directly enters the gas-liquid separator without being evaporated by the condenser, and the gaseous refrigerant is less, so that the low pressure detected by the low pressure sensor is low, the reason may be that the actual opening of the heating expansion valve is obviously smaller than the opening of the heating expansion valve, so that a large amount of refrigerant is not evaporated by the condenser but directly bypassed into the gas-liquid separator; 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 greater than or equal to the fifth preset temperature, the temperature of the inlet side of the gas-liquid separator is obviously greater than the temperature of the low pressure side of the compressor, which indicates that the refrigerant is fully evaporated in the condenser and a sufficient suction superheat degree is obtained, and the reason may be that the actual opening degree of the heating expansion valve is obviously smaller than the opening degree of the heating expansion valve at this time, so that the refrigerant flowing through the condenser is less.

Furthermore, in some embodiments, the method further comprises: if the absolute value of the difference between the opening of the heating expansion valve and the opening of the supercooling expansion valve is larger than or equal to the first preset opening, and the opening of the heating expansion valve is smaller than the opening of the supercooling expansion valve, judging whether the opening of the heating expansion valve is larger than the opening or not based on a third preset judging condition; if the opening degree of the heating expansion valve is larger than the opening degree of the opening, 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 exchanges heat effectively at the condenser or not based on the first preset judging condition again.

That is, in the case where the opening difference between the heating expansion valve and the supercooling expansion valve is large and the opening of the heating expansion valve is larger than the opening of the supercooling expansion valve, in this embodiment, based on the third preset determination condition, it is determined whether the opening of the heating expansion valve is larger than the opening, if the opening of the heating expansion valve is larger than the opening, it is indicated that the heating expansion valve and the supercooling expansion valve may be reversely connected (that is, the opening of the heating expansion valve which should be smaller is indicated that the actual opening is larger instead), so in this embodiment, in order to verify whether the determination is correct, the opening of the supercooling expansion valve is controlled to be equal to zero and the opening of the heating expansion valve is controlled to be equal to the third preset opening, and after the second preset operation is continued, it is determined whether the refrigerant is effectively heat exchanged at the condenser again based on the first preset determination condition, that is, the opening of the supercooling expansion valve and the heating expansion valve is reset, so that the opening of the two satisfies the conditions of executing step S202 and the subsequent steps, thereby judging whether the supercooling expansion valve and the heating expansion valve are reversely connected according to the corresponding conditions. The third preset opening degree may be the same as or different from the second preset opening degree.

Further, as a possible embodiment, 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: if the difference between the ambient temperature and the low-pressure side temperature of the compressor is smaller than or equal to a sixth preset temperature, and/or the difference between the inlet side temperature of the gas-liquid separator and the low-pressure side temperature of the compressor is smaller than or equal to a seventh preset temperature, determining that the opening of the heating expansion valve is larger than the opening.

That is, when the difference between the ambient temperature and the low pressure side temperature of the compressor is less than or equal to the sixth preset temperature, indicating that the low pressure in the environment is higher, indicating that a large amount of refrigerant in the inlet pipe of the gas-liquid separator is evaporated through the condenser, the amount of gaseous refrigerant is more, and the low pressure detected by the low pressure sensor is higher, because the actual opening of the heating expansion valve is obviously greater than the opening of the heating expansion valve, and a large amount of refrigerant is evaporated through the condenser, and the amount of 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 smaller than or equal to the seventh preset temperature, the suction superheat degree is smaller or the suction superheat degree is not smaller, which means that the refrigerant is not completely evaporated in the condenser, and the reason may be that the actual opening of the heating expansion valve is obviously larger than the opening of the heating expansion valve at the moment, so that the refrigerant flowing through the condenser is more.

The above embodiments describe a method for determining whether an expansion valve is reversely connected in a heating mode, and in addition, the present application further provides a corresponding determination method in a cooling mode, and referring to fig. 3, fig. 3 is a schematic flow chart of another determination method for reversely connecting an expansion valve provided in an embodiment of the present application; as shown in fig. 3, the method at least comprises the following steps:

s301: judging whether the opening of the supercooling expansion valve is larger than zero in a refrigerating mode;

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

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

specifically, if the opening of the supercooling expansion valve is not greater than zero, that is, the supercooling 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 to perform heat exchange (heat release in the refrigeration mode) after passing through the heating expansion valve, so in this embodiment, whether the two expansion valves are reversely connected is determined by judging whether the refrigerant is effectively subjected to heat exchange at the condenser.

Further, as a possible implementation manner, based on a fourth preset judging condition, judging whether the refrigerant is effective for heat exchange at the condenser may specifically include: if the temperature of the high-pressure side of the compressor is continuously higher than or equal to the eighth preset temperature in 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 exchange heat effectively at the condenser.

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

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

Through the scheme, in the refrigeration mode, the unit can automatically judge whether the supercooling expansion valve and the heating expansion valve are reversely connected, so that the unit can be ensured not to be failed or damaged due to reverse connection of the expansion valve based on the reverse connection, and the judgment process does not need to be manually participated, so that the labor cost can be effectively saved.

In addition, in other embodiments, the method further includes:

if the opening of the supercooling expansion valve is larger than zero, judging whether the difference value between the opening of the heating expansion valve and the opening of the supercooling expansion valve is larger than or equal to a fourth preset opening; if the difference between the opening of the heating expansion valve and the opening of the supercooling expansion valve is larger than or equal to a fourth preset opening, judging whether the difference 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 in a continuous fourth preset time; if the difference is continuously smaller than or equal to the tenth preset temperature within the fourth preset time, controlling the opening of the supercooling expansion valve to be equal to zero and controlling the opening of the heating expansion valve to be equal to the fifth preset opening, and judging whether the refrigerant exchanges heat effectively at the condenser or not again based on the fourth preset judging condition after continuously running for the fifth preset time.

Specifically, the opening of the supercooling expansion valve is greater than zero, that is, the supercooling expansion valve is not completely closed, under this condition, the refrigerant flowing out of the heating expansion valve does not all directly enter the supercooler (part of the refrigerant will first pass through the supercooling expansion valve and then enter the supercooler), so whether the expansion valve is reversely connected cannot be accurately judged through the fourth preset judgment condition, and based on this, whether the expansion valve is reversely connected is judged through other modes, specifically: judging whether the difference between the opening of the heating expansion valve and the opening of the supercooling expansion valve is larger than or equal to a fourth preset opening, namely judging whether the opening of the heating expansion valve is obviously larger than the opening of the supercooling expansion valve (because the heating expansion valve is fully opened in a refrigerating mode, the situation that the opening of the heating expansion valve is smaller than the opening of the supercooling expansion valve is not needed to be considered); when the difference value of the opening degrees is larger than or equal to the fourth preset opening degree, the opening degree of the supercooling expansion valve is smaller, and most of the refrigerant flowing out of the heating expansion valve does not flow through the cooling expansion valve at the moment, therefore, under the working condition, if the two expansion valves are in reverse connection abnormality, the unit operation parameters (such as temperature parameters) are obviously different from those in normal conditions, so that whether the expansion valves are in reverse connection can be judged and is necessary;

In this embodiment, when the difference between the opening of the heating expansion valve and the opening of the supercooling expansion valve is greater than or equal to the fourth preset opening, 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 for the fourth preset time, if so, the outlet side temperature (outlet pipe temperature) of the gas-liquid separator is lower than the low pressure side temperature of the compressor, and a large amount of liquid refrigerant may be bypassed in the gas-liquid separator, that is, the actual opening of the supercooling expansion valve is large, and the expansion valve may be reversely connected to the normal condition. In order to further verify and judge whether the refrigerant is correct, in this embodiment, the opening degree of the supercooling expansion valve is further controlled to be equal to zero, the opening degree of the heating expansion valve is further controlled to be equal to a fifth preset opening degree, and after the fifth preset time is continuously operated, whether the refrigerant is subjected to effective heat exchange at the condenser is judged again based on the fourth preset judging condition, that is, the opening degrees of the supercooling expansion valve and the heating expansion valve are reset, so that the opening degrees of the supercooling expansion valve and the heating expansion valve meet the conditions of executing step S302 and the subsequent steps, and whether the supercooling expansion valve and the heating expansion valve are reversely connected is judged again according to the corresponding conditions.

When the difference of the opening degrees is smaller than the fourth preset opening degree, 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 relatively close, 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, even if the two expansion valves are reversely connected, the unit operation is not obviously influenced, and therefore, the unit operation is controlled according to normal control logic.

In addition, when the unit parameters do not accord with the situation that the supercooling expansion valve and the heating expansion valve are reversely connected, the unit parameters are continuously controlled according to the normal control logic.

Further, in some embodiments, after determining that the subcooled expansion valve and the heated expansion valve are in reverse, the method further comprises: and controlling the machine set to stop and reporting the reverse connection fault of the expansion valve. That is, after the supercooling expansion valve and the heating expansion valve are reversely connected, the unit is stopped and a maintenance person is informed to check and maintain.

In yet other embodiments, after determining that the subcooled expansion valve and the heating expansion valve are in reverse, the method further comprises: and based on the control logic of the current mode, the supercooling expansion valve and the heating expansion valve are controlled in a switching mode until the unit is powered off. That is, after the reverse connection of the supercooling expansion valve and the heating expansion valve is determined, the machine set is not controlled to stop, and the supercooling expansion valve and the heating expansion valve are controlled to be switched, so that the machine set continues to normally operate, and the reliability of the machine set is improved.

In addition, it should be noted that, in order to avoid erroneous judgment, the judgment as to whether the opening of the supercooling expansion valve is greater than zero specifically includes: and after the unit is at least electrified and operated for a sixth preset time, judging whether the opening degree of the supercooling expansion valve is larger than zero or not. That is, in either the cooling mode or the heating mode, it is preferable that the operation is restarted for a certain period of time after the power of the unit is turned off, and the above steps of determining whether the expansion valve is reversely connected are started again after the steady state is entered.

In addition, based on the same inventive concept, the application also provides a device for judging reverse connection of the expansion valve, which corresponds to the method of the embodiment. The apparatus is a software and/or hardware based functional module in a device for 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 the opening of the supercooling expansion valve is greater than zero in the heating mode;

the second judging module 42 is configured to judge whether the refrigerant exchanges heat effectively at the condenser based on the first preset judging condition if the opening of the supercooling expansion valve is not greater than zero;

And the determining module 43 is used for determining that the supercooling expansion valve and the heating expansion valve are reversely connected if the refrigerant does not exchange heat effectively at the condenser in the heating mode.

Optionally, when determining whether the refrigerant is effectively exchanging heat at the condenser based on the 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 to be not 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 controlled in a switching mode, and whether the refrigerant is subjected to effective heat exchange at the condenser is judged again after the first preset time is continuously operated;

correspondingly, the determining module 43 is configured to:

Optionally, the device further includes a third judging module, configured to:

Optionally, the third judging module is further configured to:

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

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

Optionally, the second judging module is specifically configured to, when judging whether the refrigerant exchanges heat effectively at the condenser based on a fourth preset judging condition:

Optionally, the third judging module is further configured to:

Optionally, the apparatus further includes:

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

The specific implementation method of the steps performed by the functional modules of the above apparatus may refer to the corresponding content of the foregoing method embodiment, which is not described in detail herein.

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 embodiment; 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, a corresponding judging method can be realized. Moreover, the specific implementation method of the steps executed by the above-mentioned program may refer to the corresponding content of the foregoing method embodiment, which is not described in detail herein.

Through the scheme, whether the opening degree of the supercooling expansion valve is larger than zero can be automatically judged; if the opening of the supercooling expansion valve is not more than zero, judging whether the refrigerant exchanges heat effectively at the condenser or not based on preset judging conditions; 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; and when the opening degree of the supercooling expansion valve is larger than zero, the supercooling expansion valve and the heating expansion valve are reversely connected through other conditions, so that the unit can be ensured not to be failed or damaged due to the reverse connection of the expansion valve based on the reverse connection, and the judgment process does not need to be manually participated, so that the labor cost can be effectively saved.

It is to be understood that the same or similar parts in the above embodiments may be referred to each other, and that in some embodiments, the same or similar parts in other embodiments may be referred to.

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

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 further implementations are included within the scope of the preferred embodiment of the present application 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 embodiments of the present application.

It is to be understood that portions of the present application may be implemented in hardware, software, firmware, or a combination thereof. In the above-described embodiments, the various steps or methods may be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, may be implemented using any one or combination of the following techniques, as is well known in the art: discrete logic circuits having logic gates for implementing logic functions on data signals, application specific integrated circuits having suitable combinational logic gates, programmable Gate Arrays (PGAs), field Programmable Gate Arrays (FPGAs), and the like.

Those of ordinary skill in the art will appreciate that all or a portion of the steps carried out in the method of the above-described embodiments may be implemented by a program to instruct related hardware, where the program may be stored in a computer readable storage medium, and where the program, when executed, includes one or a combination of the steps of the method embodiments.

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

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

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," 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 present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. 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 will be understood that the above embodiments are illustrative and not to be construed as limiting the application, and that variations, modifications, alternatives, and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the application.

Claims

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

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

further comprises:

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

3. The method of claim 1, wherein said determining a reverse connection of a subcooled expansion valve and a heated expansion valve further comprises:

4. The method as recited in claim 1, further comprising:

5. The method according to claim 1, wherein the determining whether the opening of the heating expansion valve is smaller than the opening to be opened based on the second preset determination condition, specifically comprises:

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

7. The method as recited in claim 1, further comprising:

8. The method of claim 7, wherein determining whether the refrigerant is exchanging heat effectively at the condenser based on a fourth preset determination condition comprises:

9. The method as recited in claim 7, further comprising:

if the difference 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 the tenth preset temperature in the fourth preset time, controlling the opening of the supercooling expansion valve to be equal to zero and controlling the opening of the heating expansion valve to be equal to the fifth preset opening, and judging whether the refrigerant exchanges heat effectively at the condenser or not based on the fourth preset judging condition again after continuously running for the fifth preset time.

10. The method of any of claims 1-9, wherein the determining a subcooled expansion valve and a heated expansion valve are reversed, and further comprising:

11. The method of any of claims 1-9, wherein the determining a subcooled expansion valve and a heated expansion valve are reversed, and further comprising:

12. The method according to any one of claims 1 to 9, wherein the determining whether the opening degree of the supercooling expansion valve is greater than zero specifically includes:

13. The device for judging reverse connection of the expansion valve is characterized by comprising the following components:

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 exchange heat effectively at the condenser in the heating mode; and if the opening of the supercooling expansion valve is larger than zero, judging whether the absolute value of the difference value between the opening of the heating expansion valve and the opening of the supercooling expansion valve is larger than or equal to a first preset opening; if the absolute value of the difference between the opening of the heating expansion valve and the opening of the supercooling expansion valve is larger than or equal to the first preset opening, and the opening of the heating expansion valve is larger than the opening of the supercooling expansion valve, judging whether the opening of the heating expansion valve is smaller than the opening or not based on a second preset judging condition; if the opening degree of the heating expansion valve is smaller than the opening degree of the opening, 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 running for a second preset time, judging whether the refrigerant exchanges heat effectively at the condenser or not based on the first preset judging condition again.

14. The apparatus of claim 13, wherein the first determining module is further configured to determine, in the refrigeration mode, whether the opening of the subcooled expansion valve is greater than zero;

15. A controller of an air conditioner, comprising:

a memory and a processor coupled to the memory;

the memory being adapted to store a program at least for implementing the method according to any one of claims 1-12;

16. An air conditioner provided with the controller of the air conditioner according to claim 15.