KR102288427B1 - Method for Defrosting of Air Conditioner for Both Cooling and Heating - Google Patents

Abstract

It is an object of the present invention to provide a defrosting method for a combined heating and cooling air conditioner for preventing excessive occurrence of defrosting time under low outdoor temperature conditions in the defrosting of the air conditioner for heating and cooling, and shortening unnecessary defrosting time due to occurrence of temporary defrost . In the defrosting method of the air conditioner for heating and cooling according to the present invention, if residual ice of the amount of ice deposited on the surface of the outdoor unit remains, the following defrost accumulation during the preset periodic defrost operation setting using the defrost controller of the air conditioner for heating and cooling You can change the driving time to go as fast as an arbitrary amount of time.

Description

Method for Defrosting of Air Conditioner for Both Cooling and Heating

The present invention relates to a defrosting method of an air conditioner for heating and cooling, for preventing excessive occurrence of defrosting time under low outdoor temperature conditions in defrosting of the air conditioner for heating and cooling, and shortening unnecessary defrosting time due to occurrence of temporary defrost.

In general, an air conditioner may connect a plurality of indoor units to one outdoor unit, and such a multi air conditioner uses each of the plurality of indoor units as a cooler or a heater while using the outdoor unit in common.

Recently, a plurality of compressors are provided or a plurality of outdoor units are connected in parallel to each other so as to effectively respond to a cooling or heating load according to the number of indoor units being operated.

At this time, the heat pump cycle has a compressor, an outdoor unit (which is used as a condenser for cooling and an evaporator for heating), an expansion valve, and an indoor unit as basic components. In the air conditioner for heating and cooling in which the heat pump is employed as described above, the compressor, the indoor unit, the expansion valve and the indoor unit are connected through a refrigerant circulation conduit, while a four-way valve is installed on one side of the conduit to selectively control the flow of refrigerant supplied from the compressor. By switching, the indoor unit operates as an evaporator during cooling and as a condenser during heating to perform heating and cooling.

1 is a view for explaining a heating operation method of a heat exchanger in the air conditioner according to the prior art.

As shown in FIG. 1 , the high-temperature, high-pressure gas refrigerant discharged from the compressor 1 flows into the indoor unit 6 through the four-way valve 2 . In addition, the high-temperature and high-pressure gaseous refrigerant transfers heat to the air introduced into the indoor unit 6 by the indoor unit fan 7 while the indoor unit 6 phase changes to the liquid refrigerant, thereby heating the indoor space. At this time, the refrigerant condensed through the above process passes through the expansion valve 5 and is converted into a refrigerant of low temperature and low pressure and flows into the outdoor unit 3 , and is evaporated by receiving heat from the outdoor air introduced by the outdoor unit fan 4 . Then, the heating function is performed by repeating the purification process flowing into the compressor (1) through the four-way valve (2) and the accumulator (8).

In the above process, when the temperature and humidity conditions are suitable for the external air to form on the surface of the outdoor unit 3, frost is formed on the surface of the outdoor unit 3, and an implantation phenomenon occurs. Due to this conception phenomenon, the heat exchange performance of the outdoor heat exchanger is lowered, and thus heating efficiency is lowered and an overload occurs.

Conventionally, in order to control the frost frozen in the outdoor heat exchanger, the defrost was performed by a means of switching to heating by controlling the four-way valve 2 in a state where both the fans of the indoor and outdoor heat exchangers were stopped.

However, during defrosting by switching between heating and cooling as described above, since the indoor temperature is not heated, the indoor temperature is continuously falling. Therefore, there is a problem in that one feels cold and discomfort due to the lowering of the indoor temperature, and since power consumption continues even during the defrosting operation, there is also an unreasonable problem in that electric power is wasted without need.

In particular, in the defrosting system implemented in the conventional air conditioner, the timing of the defrosting is determined according to the temperature change and the low pressure change rate of the outdoor heat exchanger. As such, since the defrost system is simply affected by the current cycle state and the defrost state is generated, there is a problem in that frequent defrost operation occurs due to misjudgment. For example, there is a problem in that a defrosting operation occurs even in a situation where defrosting is not required due to a low pressure drop due to a shortage of refrigerant or a low pressure drop due to a drop in the outside temperature.

As a method to solve this problem, periodic defrost logic according to the accumulated operating time using the current outdoor temperature and the heat exchanger temperature in Korean Patent Publication No. 10-1229726 (a heat pump and an ignition prevention device and a control method therefor) We propose a configuration that applies

However, even when the periodic defrost logic according to the accumulated operation time using the outdoor temperature and the heat exchanger temperature is applied as described above, if the amount of frost freezing on the surface of the outdoor unit 3 is excessive, the frozen frosting occurs even during the accumulated defrost operation time. There is a problem in that the amount of ice cannot be completely melted and residual ice is generated.

In addition, when the periodic defrost logic is applied, there is a problem in that residual ice is generated due to a decrease in the defrost performance due to a decrease in the condensation temperature under a low outdoor temperature condition. Conversely, there is a problem in that unnecessary defrosting operation occurs because the outdoor heat exchanger temperature is low when there is no ignition under low outdoor temperature conditions, and unnecessary defrosting time occurs.

It is an object of the present invention to provide a defrosting method for a combined heating and cooling air conditioner for preventing excessive occurrence of defrosting time under low outdoor temperature conditions in the defrosting of the air conditioner for heating and cooling, and shortening unnecessary defrosting time due to occurrence of temporary defrost .

It is also an object of the present invention to provide a defrosting method of an air conditioner combined with heating and cooling to prevent excessive occurrence of defrost time under low outdoor temperature conditions in the defrost of the air conditioner for heating and cooling, and to shorten unnecessary defrost time due to occurrence of temporary defrost. will be.

Another object of the present invention is to provide a defrosting method of an air conditioner for heating and cooling, which can increase heating efficiency and stability by securing heating time by shortening unnecessary defrosting time.

Another object of the present invention is to provide a defrosting method of an air conditioner for heating and cooling, which can improve product reliability through effective prevention of accumulated freezing.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention not mentioned may be understood by the following description, and will be more clearly understood by the examples of the present invention. Moreover, it will be readily apparent that the objects and advantages of the present invention may be realized by the means and combinations thereof indicated in the claims.

The defrosting method of the air conditioner combined with heating and cooling according to the present invention can prevent excessive occurrence of defrost time under low outdoor temperature conditions in the defrost of the air conditioner combined with heating and cooling, and can shorten unnecessary defrost time due to the occurrence of temporary defrost.

In addition, the defrosting method of the air conditioner combined with heating and cooling according to the present invention uses the defrost controller of the air conditioner for heating and cooling when residual ice of the amount of ice deposited on the surface of the outdoor unit remains, using the defrost controller of the air conditioner for heating and cooling. The accumulated operation time can be changed to advance as quickly as an arbitrary time.

Also, in the defrosting method of the air conditioner for heating and cooling according to the present invention, when the amount of implantation on the surface of the outdoor unit is determined to be all melted during the defrosting operation, the current operating periodic defrosting operation is terminated using the defrost controller of the air conditioner for heating and cooling. can do.

In addition, the defrosting method of the air conditioner combined with heating and cooling according to the present invention includes a second determination step of determining whether a defrost operation termination condition during the defrosting operation; terminating the current periodic defrosting operation by using the defrost controller of the air conditioner combined with heating and cooling if it is determined that the defrost operation termination condition is determined as a result of the second determination; a third determination step of determining whether the first condition for determining whether residual ice of the amount of ice on the surface of the outdoor unit is satisfied when it is determined that the defrost operation termination condition is not satisfied as a result of the second determination; a fourth determination step of, if it is determined that the first condition is not satisfied as a result of the third determination, a fourth determination step of re-determining whether the second condition for determining whether residual ice of the amount of ice formed on the surface of the outdoor unit is satisfied; and when it is determined that the first condition or the second condition is satisfied, the next defrost accumulated operation time among the preset periodic defrost operation settings is advanced by an arbitrary amount of time by using the defrost controller of the air conditioner combined with heating and cooling. and terminating the current periodic defrost operation.

In addition, the defrosting method of the air conditioner combined with heating and cooling according to the present invention includes a second determination step of determining whether a defrost operation termination condition; terminating the current periodic defrosting operation by using the defrost controller of the air conditioner combined with heating and cooling if it is determined that the defrost operation termination condition is determined as a result of the second determination; determining whether the first condition or the second condition for determining whether residual ice of the amount of ice deposited on the surface of the outdoor unit is satisfied when it is determined that the defrost operation termination condition is not satisfied as a result of the second determination; and if the first condition or the second condition is satisfied, using a defrost controller of the air conditioner for heating and cooling, changing the accumulated next defrost operation time of the preset periodic defrost operation setting to proceed as quickly as an arbitrary time. may include.

The defrosting method of the air conditioner combined with heating and cooling according to the present invention can prevent excessive occurrence of defrost time under low outdoor temperature conditions in the defrost of the air conditioner combined with heating and cooling, and shorten unnecessary defrosting time due to the occurrence of temporary defrost.

In addition, the defrosting method of the air conditioner for heating and cooling according to the present invention can increase heating efficiency and stability by securing heating time by shortening unnecessary defrosting time.

In addition, the defrosting method of the air conditioner combined with heating and cooling according to the present invention can improve the reliability of the product through effective prevention of accumulated freezing.

In addition to the above-described effects, the specific effects of the present invention will be described together while describing specific details for carrying out the invention below.

1 is a view for explaining a heating operation method of a heat exchanger in the air conditioner according to the prior art.
2 is a block diagram showing the configuration of the air conditioner for heating and cooling according to the present invention.
3 is a configuration diagram showing the configuration of the outdoor heat exchanger in detail in FIG.
4 is a flowchart illustrating a defrosting method of an air conditioner for heating and cooling according to an embodiment of the present invention.
5 and 6 are diagrams showing simulation/test data showing the results of the periodic defrosting operation of the air conditioner for heating and cooling according to the prior art.
7 and 8 are views showing simulation/test data showing the results of the periodic defrosting operation of the air conditioner for heating and cooling according to the present invention.
FIG. 9(a) is an image taken directly from the outdoor unit to indicate the amount of frost that is formed on the surface of the outdoor unit during the periodic defrosting operation of the air conditioner for heating and cooling according to the prior art.
FIG. 9(b) is an image taken directly from the outdoor unit to indicate the amount of frost implanted on the surface of the outdoor unit during the periodic defrosting operation of the air conditioner for heating and cooling according to the present invention.

The above-described objects, features and advantages will be described below in detail with reference to the accompanying drawings, and accordingly, those of ordinary skill in the art to which the present invention pertains will be able to easily implement the technical idea of the present invention. In describing the present invention, if it is determined that a detailed description of a known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

Although the first, second, etc. are used to describe various elements, these elements are not limited by these terms, of course. These terms are only used to distinguish one component from other components, and unless otherwise stated, the first component may be the second component, of course.

Throughout the specification, unless otherwise stated, each element may be singular or plural.

In the following, that an arbitrary component is disposed on the "upper (or lower)" of a component or "upper (or below)" of a component means that any component is disposed in contact with the upper surface (or lower surface) of the component. Furthermore, it may mean that other components may be interposed between the component and any component disposed on (or under) the component.

Also, when it is described that a component is "connected", "coupled" or "connected" to another component, the components may be directly connected or connected to each other, but other components are "interposed" between each component. It is to be understood that “or, each component may be “connected,” “coupled,” or “connected” through another component.

As used herein, the singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as "consisting of" or "comprising" should not be construed as necessarily including all of the various components or various steps described in the specification, some of which components or some steps are It should be construed that it may not include, or may further include additional components or steps.

Hereinafter, a defrosting method of an air conditioner for heating and cooling according to some embodiments of the present invention will be described.

2 is a block diagram showing the configuration of an air conditioner for heating and cooling according to the present invention.

As shown in FIG. 2, the air conditioner combined with heating and cooling includes first, second, third, and fourth indoor units (B1, B2, B3, B4) (B), and outdoor unit (A) and distributor (C) for heating and cooling. includes

The outdoor unit A for heating and cooling includes first and second compressors 53 and 54 , an outdoor heat exchanger 51 , an outdoor heat exchanger fan 61 , and a switching unit. Here, the switching unit includes a four-way valve 62 . The suction portions of the first and second compressors 53 and 54 are connected by a common accumulator 52 . The first compressor 53 is an inverter compressor capable of varying the compression capacity of the refrigerant, and the second compressor 54 is a constant speed compressor having a constant compression capacity of the refrigerant.

The first and second discharge pipes 55 and 56 are connected to the discharge portions of the first and second compressors 53 and 54 , and the first and second discharge pipes 55 and 56 are connected to the laminating unit 57 . first and second oil separators 58 and 59 to recover oil from the refrigerant discharged from the first and second compressors 53 and 54 in the first and second discharge pipes 55 and 56 each is installed. In the first and second oil separators 58 and 59 , the oil separated from the first and second oil separators 58 and 59 is guided to the suction part of the first and second compressors 53 and 54 , the first ,2 oil return pipes 30 and 31 are connected.

A high-pressure gas pipe 63 through which the refrigerant discharged from the first and second compressors 53 and 54 is bypassed without passing through the four-way valve 62 is connected to the bonding unit 57 . In addition, the lap portion 57 is connected to the four-way valve 57 and the third discharge pipe (68).

The outdoor heat exchanger (51) is connected to the four-way valve (62) by a first connection pipe (71). In the outdoor heat exchanger (51), the refrigerant is condensed or evaporated by heat exchange with the outside air. At this time, in order to facilitate heat exchange, the outdoor fan 61 introduces air into the outdoor heat exchanger 51 . In the simultaneous heating and cooling type multi-air conditioner, the outdoor heat exchanger 51 is used as a condenser during all cooling room operation or simultaneous cooling main operation, and the outdoor heat exchanger 51 is used as an evaporator during heating all room operation or heating main simultaneous operation. .

On the liquid pipe 72 connecting the outdoor heat exchanger 51 and the distributor C, an outdoor electronic expansion valve 65 and a supercooling device 66 are installed. The outdoor electronic expansion valve 65 expands the refrigerant during operation of the entire heating room or simultaneous operation of the heating main body.

The supercooling device 66 cools the refrigerant moved to the distributor C during the operation of the entire cooling room or the simultaneous operation of the cooling main body. The outdoor electronic expansion valve 74 transfers the refrigerant condensed in the first, second, third, and fourth indoor heat exchangers 11, 21, 32, and 41 to the outdoor heat exchanger 51 during operation of the entire heating room or simultaneous operation of the heating main body. Inflate before entering. The supercooling device 66 includes a supercooler 66a installed to surround a part of the liquid pipe 72 and a portion of the refrigerant that is disposed between the supercooler 66a and the distributor C and moves to the distributor C. The bypass pipe 66b for bypassing the inside of the subcooler 66a, the electromagnetic expansion valve 66c installed in the bypass pipe 66b, and the supercooler 66a and the third discharge pipe 64 are connected. and a recovery pipe 66d.

The distributor (C) is arranged between the outdoor unit (A) for heating and cooling and the indoor units (B1, B2, B3, B4) (B) for the first, second, third, It is distributed to the first, second, third, and fourth indoor units (B1, B2, B3, B4) (B) for simultaneous heating and cooling according to the simultaneous and heating principal simultaneous operation conditions. The distributor C draws in and mixes the high-pressure gas header 81, the low-pressure gas header 82, the liquid header 83, and the air flowing out and the indoor air to cool and heat the drawn indoor air (IDU). ) (Heat Recovery Unit) including 86, a pipe 84 for moving the flow rate of high-pressure refrigerant, low-pressure refrigerant, liquid, etc., and a control valve 85 for controlling the flow rate of the pipe 84. may include

The first, second, third, and fourth indoor units (B1, B2, B3, B4) (B) have first, second, third, and fourth indoor heat exchangers 11, 21, 31, 41, respectively; Includes first, second, third, and fourth indoor electronic expansion valves 12, 22, 32, and 42 and first, second, third, and fourth indoor fans 15, 25, 35, and 45. do. The first, second, third, and fourth indoor electronic expansion valves 12, 22, 32, and 42 are the first, second, third, and fourth indoor heat exchangers 11, 21, 31, and 41. It is installed on the first, second, third, and fourth indoor connecting pipes 13, 23, 33, and 43 connecting the high-pressure gas header 81 and the high-pressure gas header 81 .

In addition, in order to detect the temperature of the refrigerant discharged from the first, second, third, and fourth combined indoor units (B1) (B2) (B3) (B4), the first, second, third, and fourth temperature sensors (16) (26), (36) and (46) may be installed. Here, the first, second, third, and fourth temperature sensors 16, 26, 36, and 46 are the first, second, third and fourth indoor heat exchangers 11, 21, 31, and 41 and It is installed on the 5th, 6th, 7th, 8th indoor connecting pipes 14, 24, 34, 44 connecting the low pressure gas header 82. Also, temperature sensors (not shown) may be installed in the first, second, third, and fourth indoor heat exchangers 11 , 21 , 31 and 41 .

The high-pressure gas header 81 is connected to one side of the high-pressure gas pipe 63 and the first, second, third, and fourth indoor heat exchangers 11, 21, 31, and 41 of the laminating unit 57, respectively. do. In addition, the low-pressure gas header 82 is connected to the suction pipe 64 by a low-pressure gas pipe 75, and the first, second, third, and fourth indoor heat exchangers 11, 21, 31 and 41 are connected to the other side. The liquid header 83 is connected to one side of the supercooling device 66 and the first, second, third, and fourth indoor heat exchangers 11, 21, 31, and 41, respectively. The high-pressure gas header 81, the low-pressure gas header 82, and the liquid header 83 include a high-pressure gas pipe 63', a low-pressure gas pipe 75', and a liquid pipe 72' of another outdoor unit (not shown). Each may be further connected.

A pipe 84 is provided between the high-pressure gas header 81 and the low-pressure gas header 82 . The pipe 84 serves to bypass the high-pressure refrigerant in the high-pressure gas header 81 to the low-pressure gas header 82 .

A control valve 85 is installed on the pipe 84 to control the flow rate of the refrigerant bypassed from the high-pressure gas header 81 to the low-pressure gas header 82 . The control valve 85 controls the flow rate of the refrigerant bypassed from the high-pressure gas header 81 to the low-pressure gas header 82 to prevent freezing of the indoor unit in the cooling operation during simultaneous heating or cooling operation.

Alternatively, the control valve 85 is opened during operation of the entire cooling chamber to bypass the residual refrigerant remaining in the high-pressure gas header 81 to the low-pressure gas header 82 . The control valve 85 may be an electronic expansion valve.

3 is a block diagram showing the configuration of the outdoor heat exchanger in detail in FIG.

3, the outdoor heat exchanger 51 includes an upper heat exchange coil 51a, a lower heat exchange coil 51b, an upper heat exchanger temperature sensor 91, a lower heat exchanger temperature sensor 92, and a heat exchanger. It may include a temperature sensor 93 .

At this time, the upper heat exchanger temperature sensor 91 detects the temperature of the refrigerant flowing from the upper valve 62 to the upper heat exchange coil 51a through the first connection pipe 71 . The temperature detected by the upper heat exchanger temperature sensor 91 is hereinafter referred to as an inlet heat exchanger temperature.

The lower heat exchanger temperature sensor 92 detects the temperature of the refrigerant flowing into the lower heat exchange coil 51b through the upper heat exchange coil 51a. The temperature detected by the lower heat exchanger temperature sensor 92 is hereinafter referred to as the lower outlet heat exchanger temperature.

The heat exchanger temperature sensor 93 detects the temperature of the refrigerant flowing into the supercooling device 66 through the lower heat exchange coil 51b. The temperature detected by the heat exchanger temperature sensor 93 is hereinafter referred to as the total heat exchanger temperature.

In addition, an outdoor temperature sensor 94 may be further included outside the outdoor heat exchanger 51 to measure the outdoor temperature.

The operation of the air conditioner for heating and cooling according to the present invention configured as described above will be described in detail with reference to the accompanying drawings. The same reference numerals as those of FIG. 2 or FIG. 3 refer to the same members performing the same functions.

4 is a flowchart illustrating a defrosting method of an air conditioner for heating and cooling according to an embodiment of the present invention. Figure 4 is to be described as an embodiment of the outdoor heat exchanger having a variable pass cycle divided into upper / lower. However, it is not limited thereto, and various embodiments may be possible within the scope of the technical idea of the present invention.

Referring to FIG. 4, first, the defrost controller of the air conditioner for heating and cooling uses the upper heat exchange coil 51a and the lower heat exchange coil (51a) through the temperature sensors 91, 92, 93 installed in the outdoor heat exchanger in the initial state. 51b) By detecting the ambient temperature, the operation conditions of the outdoor heat exchanger are determined (first determination) as the cooling and heating operation conditions and the periodic defrosting operation conditions (S10).

Periodic defrost operation conditions are: First, the outdoor temperature is -34℃~4℃, the inlet heat exchanger temperature < -4℃ after accumulated operation for 90 minutes, the condition is satisfied for 3 minutes, Second, the outdoor temperature is less than -3℃, 120 minutes of operation After accumulation, the inlet heat exchanger temperature < -6 ℃, any one of the conditions satisfying 3 minutes can be determined as the periodic defrost operation condition.

However, the periodic defrost operation conditions are not limited thereto, and may be changeable.

When the first determination result (S10) confirms the periodic defrost operation condition (S20), the defrost controller of the air conditioner for heating and cooling operates the periodic defrost operation at a set cycle (S30).

And the defrost controller of the air conditioner combined with heating and cooling determines (second determination) whether the defrost operation termination condition while the periodic defrost operation is being operated (S40).

Periodic defrost operation termination conditions are: First, the condition that the total heat exchanger temperature is greater than the first threshold (A) temperature (A°C) is satisfied to maintain the first set time (x seconds), second, the inlet heat exchanger temperature It can be determined as the periodic defrost operation termination condition in any one of the conditions that satisfy the second threshold (B) temperature (B ℃) is greater than the second set time (y seconds) to be maintained.

If the second determination result (S40) is determined to be the defrost operation termination condition, the defrost controller of the air conditioner combined with heating/cooling ends the current periodic defrost operation and operates the cooling/heating operation (S90).

On the other hand, if it is determined in the second determination result (S40) that the defrost operation end condition is not, the following three first methods for determining whether residual ice of the amount of ice deposited on the surface of the outdoor unit 3 remain after 5 minutes of the defrost operation It is determined whether all conditions are satisfied (third determination) (S50).

The first condition of the third determination (S50) may include: first, the inlet heat exchanger temperature is less than -1 ℃, second, a continuous decrease for 30 seconds, and third, the lower outlet heat exchanger temperature is less than 0 ℃. there is.

As a result of the third determination ( S50 ), if it is determined that any one of the three first conditions is not satisfied, the following second condition for determining whether residual ice of the amount of implanted ice remains on the surface of the outdoor unit 3 is satisfied It is determined again (fourth determination) whether or not (S60).

The second condition of the fourth determination ( S60 ) may include a condition in which the inlet heat exchanger temperature is lower than -1°C and the lower outlet heat exchanger temperature is lower than 0°C, maintained for 1 minute.

When it is determined that the first condition or the second condition of the third determination result ( S50 ) or the fourth determination result ( S60 ) is satisfied, the defrost controller of the air conditioner combined with heating and cooling performs the next defrost during the set periodic defrost operation setting. The accumulated operation time is set to proceed as quickly as an arbitrary time (30 minutes) (S80).

At this time, the determination that the first condition or the second condition of the third determination result ( S50 ) or the fourth determination result ( S60 ) is satisfied is determined even during the accumulated defrost operation time because the amount of frost on the surface of the outdoor unit 3 is large. It means that all frozen implantation amount has not been melted. Therefore, by setting the next cumulative defrost operation time to advance faster than the previous cycle, the defrost operation can be performed so that all residual ice of the implantation amount can be melted by the next cumulative defrost operation.

Then, the defrost controller of the air conditioner combined with heating and cooling terminates the current periodic defrost operation, and operates the heating and cooling operation (S90).

On the other hand, if it is determined that either the first condition or the second condition of the third determination result ( S50 ) or the fourth determination result ( S60 ) is not satisfied, the amount of implantation on the surface of the outdoor unit 3 is all melted It is determined whether the following two third conditions are satisfied (fifth determination) (S70).

The third condition of the fifth determination (S70) is that, first, the inlet heat exchanger temperature is 5°C or higher, and second, (lower outlet heat exchanger temperature - inlet heat exchanger temperature) is less than 1°C, which is maintained for 3 minutes or longer. Conditions may be included.

If it is determined that the third condition of the fifth determination result (S70) is satisfied, the defrost controller of the air conditioner combined with heating and cooling maintains the currently operating periodic defrost operation for 3 minutes and then ends the currently operating periodic defrost operation, , the heating and cooling operation is operated (S100).

5 and 6 are diagrams showing simulation/test data showing the results of the periodic defrosting operation of the air conditioner for heating and cooling according to the prior art, and FIGS. 7 and 8 are the periodic defrosting operation of the air conditioner for heating and cooling according to the present invention. It is a diagram showing simulation/test data showing the results.

5 to 8 are simulation/test data results that appear during the conventional low-temperature defrosting operation, and show the amount of change in pressure and temperature over time under conditions of an outdoor temperature of -20°C and a humidity of 80%.

In more detail, in the case of the defrost operation of the prior art shown in FIG. 5, the defrost operation time is operated in a period of 20 minutes to 21 minutes. In contrast, in the case of the defrost operation of the present invention shown in FIG. 7 , it can be seen that the defrost operation time is operated in a period of 9 minutes to 10 minutes. As such, it is possible to prevent excessive occurrence of unnecessary defrosting time because the temperature of the external heat exchanger is low when there is no ignition in the low external air condition.

And when looking at the stability of the pressure, it can be seen that the pressure value generated in the case of the defrosting operation of the present invention is more stable than in the case of the defrosting operation of the prior art based on the pressure value of 2000. This means that the heating efficiency is stable.

In addition, the temperature change in the case of the defrost operation of the present invention shown in FIG. 8 is more stable than in the case of the defrost operation of the prior art shown in FIG. 6, and the time to maintain the changed temperature due to the defrost operation is also shorter. it can be seen that This means that the heating time can be further secured by shortening the unnecessary defrosting time, thereby increasing the heating efficiency.

9(a) is an image taken directly from the outdoor unit to show the amount of frost that is implanted on the surface of the outdoor unit during the periodic defrosting operation of the air conditioner for heating and cooling according to the prior art, and FIG. 9(b) is the present invention. This is an image taken directly from the outdoor unit to show the amount of frost on the surface of the outdoor unit during the periodic defrosting operation of the air conditioner for heating and cooling.

9(a)(b) shows an experiment was conducted under conditions of an outdoor temperature of -10°C and a humidity of 85% in order to allow frost to form on the surface of the outdoor unit.

In the case of the periodic defrosting operation of the prior art shown in FIG. 9( a ), it can be confirmed that frost is formed on the surface of the outdoor unit. In contrast, in the case of the periodic defrosting operation of the present invention shown in FIG. 9(b), it can be confirmed that there is no residual ice on the surface of the outdoor unit.

Through these experimental results, in the case of the periodic defrost operation method of the present invention, unnecessary defrost time can be shortened and heating time can be secured to increase heating efficiency and stability. In addition, it is possible to improve the reliability of the product through the effective prevention of accumulated freezing.

As described above, the present invention has been described with reference to the illustrated drawings, but the present invention is not limited by the embodiments and drawings disclosed in the present specification. It is obvious that variations can be made. In addition, although the effects according to the configuration of the present invention are not explicitly described and described while describing the embodiments of the present invention, it is natural that the effects predictable by the configuration should also be recognized.

Claims (20)

a second determination step of determining whether a defrost operation termination condition exists during the operation of the defrost operation;
terminating the current periodic defrosting operation by using the defrost controller of the air conditioner combined with heating and cooling if it is determined as the defrost operation termination condition as a result of the second determination;
a third determination step of determining whether the first condition for determining whether residual ice of the amount of ice deposited on the surface of the outdoor unit is satisfied when it is determined that the defrost operation termination condition is not met as a result of the second determination;
a fourth determination step of, if it is determined that the first condition is not satisfied as a result of the third determination, a fourth determination step of re-determining whether a second condition for determining whether the amount of ice remaining on the surface of the outdoor unit is satisfied; and
If it is determined that the first condition or the second condition is satisfied, using the defrost controller of the air conditioner combined with heating and cooling, the next defrost accumulation operation time among the preset periodic defrost operation settings is changed to advance as quickly as an arbitrary time And, including the step of terminating the period defrost operation currently in operation,
In the second determination step, the defrosting method of the air conditioner combined with heating and cooling determines the defrost operation termination condition using the total heat exchanger temperature, the time to maintain it, and the inlet heat exchanger temperature and the time to maintain it.
delete According to claim 1,
The first condition is a defrosting method of an air conditioner for heating and cooling using an inlet heat exchanger temperature, a continuous reduction time, and a lower outlet heat exchanger temperature.
4. The method of claim 3,
The first condition is: First, the inlet heat exchanger temperature is less than -1 ℃, second, while continuously decreasing for 30 seconds, third, the lower outlet heat exchanger temperature is less than 0 ℃ defrost method of an air conditioner combined with air conditioning including a condition .
According to claim 1,
The second condition is a defrosting method of an air conditioner for heating and cooling using a time for maintaining the temperature using the temperature of the inlet heat exchanger and the temperature of the lower outlet heat exchanger.
6. The method of claim 5,
The second condition is a defrosting method of an air conditioner for heating and cooling, including a condition in which the inlet heat exchanger temperature is lower than -1°C and the lower outlet heat exchanger temperature is lower than 0°C for 1 minute.
According to claim 1,
a fifth determination step of determining whether any of the first condition and the second condition is satisfied, when it is determined that any one of the first condition and the second condition is satisfied, a third condition for determining a state in which the amount of implantation on the surface of the outdoor unit is all melted; and
When it is determined that the third condition is satisfied, the defrosting method of the heating/cooling air conditioner further comprising the step of using a defrost controller of the heating/cooling/heating/cooling air conditioner to end the current periodic defrosting operation.
8. The method of claim 7,
The third condition is a defrosting method of an air conditioner for heating and cooling by using the difference between the inlet heat exchanger temperature and (lower outlet heat exchanger temperature - inlet heat exchanger temperature) and time to maintain the temperature.
9. The method of claim 8,
The third condition is the defrost of the air conditioner for heating and cooling, including a condition in which the inlet heat exchanger temperature is 5°C or higher and (lower outlet heat exchanger temperature - inlet heat exchanger temperature) is maintained for 3 minutes or longer when the temperature is less than 1°C. method.
According to claim 1,
The defrost operation is
A first determination step of detecting the temperature around the upper heat exchange coil and the lower heat exchange coil of the outdoor heat exchanger to determine the cooling/cooling operation condition and the periodic defrosting operation condition of the outdoor heat exchanger; and
and operating the periodic defrosting operation at a preset cycle using a defrosting controller of the air conditioner combined with heating and cooling if the condition for the periodic defrosting operation is confirmed as a result of the first determination.
11. The method of claim 10,
The first determination step is
A defrosting method of an air conditioner combined with heating and cooling, which is determined as a periodic defrosting operation condition using the outdoor temperature, the inlet heat exchanger temperature after accumulated operation for a certain period of time, and the time to maintain the outdoor temperature and the inlet heat exchanger temperature.
a second determination step of determining whether a defrost operation termination condition exists;
terminating the currently operating periodic defrosting operation by using the defrost controller of the air conditioner combined with heating and cooling if it is determined as a defrost operation termination condition as a result of the second determination;
determining whether a first condition or a second condition for determining whether residual ice of the amount of ice formed on the surface of the outdoor unit is satisfied if it is determined that the defrost operation termination condition is not met as a result of the second determination; and
If the first condition or the second condition is satisfied, using the defrost controller of the air conditioner for heating and cooling, changing the accumulated next defrost operation time of the preset periodic defrost operation setting to proceed as quickly as an arbitrary time. including,
In the second determination step, the defrosting method of the air conditioner combined with heating and cooling determines the defrost operation termination condition using the total heat exchanger temperature, the time to maintain it, and the inlet heat exchanger temperature and the time to maintain it.
13. The method of claim 12,
The first condition is a defrosting method of an air conditioner for heating and cooling using an inlet heat exchanger temperature, a continuous reduction time, and a lower outlet heat exchanger temperature.
14. The method of claim 13,
The first condition is: First, the inlet heat exchanger temperature is less than -1 ℃, second, while continuously decreasing for 30 seconds, third, the lower outlet heat exchanger temperature is less than 0 ℃ defrost method of an air conditioner combined with heating and cooling including a condition .
13. The method of claim 12,
The second condition is a defrosting method of an air conditioner for heating and cooling using a time for maintaining the temperature using the temperature of the inlet heat exchanger and the temperature of the lower outlet heat exchanger.
16. The method of claim 15,
The second condition is a defrosting method of an air conditioner for heating and cooling, including a condition in which the inlet heat exchanger temperature is lower than -1°C and the lower outlet heat exchanger temperature is lower than 0°C for 1 minute.
13. The method of claim 12,
a fifth determination step of determining whether any of the first condition and the second condition is satisfied, when it is determined that any one of the first condition and the second condition is satisfied, a third condition for determining a state in which the amount of implantation on the surface of the outdoor unit is all melted;
When it is determined that the third condition is satisfied, the defrosting method of the heating/cooling/heating/cooling/air conditioner further comprising the step of terminating the current periodic defrosting operation using the defrosting controller of the air conditioner.
18. The method of claim 17,
The third condition is a defrosting method of an air conditioner for heating and cooling by using the difference between the inlet heat exchanger temperature and (lower outlet heat exchanger temperature - inlet heat exchanger temperature) and time to maintain the temperature.
19. The method of claim 18,
The third condition is the defrost of the air conditioner for heating and cooling, including a condition in which the inlet heat exchanger temperature is 5°C or higher and (lower outlet heat exchanger temperature - inlet heat exchanger temperature) is maintained for 3 minutes or longer when the temperature is less than 1°C. method.
13. The method of claim 12,
The defrost operation is
A first determination step of detecting the temperature around the upper heat exchange coil and the lower heat exchange coil of the outdoor heat exchanger to determine the cooling/cooling operation condition and the periodic defrosting operation condition of the outdoor heat exchanger; and
and operating the periodic defrosting operation at a preset cycle using a defrosting controller of the air conditioner combined with heating and cooling if the condition for the periodic defrosting operation is confirmed as a result of the first determination.

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