(19)
(11) EP 2 354 724 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Mention of the grant of the patent:
03.04.2024 Bulletin 2024/14

(21) Application number: 11153578.7

(22) Date of filing: 07.02.2011
(51) International Patent Classification (IPC): 
F25B 13/00(2006.01)
F25B 40/00(2006.01)
F25B 49/00(2006.01)
(52) Cooperative Patent Classification (CPC):
F25B 49/005; F25B 2500/222

(54)

Air conditioner and method for controlling air conditioner

Klimaanlage und Verfahren zur Steuerung einer Klimaanlage

Climatiseur d'air et son procédé de commande


(84) Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30) Priority: 08.02.2010 KR 20100011515

(43) Date of publication of application:
10.08.2011 Bulletin 2011/32

(73) Proprietor: LG Electronics Inc.
Youngdungpo-gu Seoul 150-721 (KR)

(72) Inventors:
  • Kwon, Kiback
    641-110, Gyeongnam (KR)
  • Kim, Sunghwan
    641-110, Gyeongnam (KR)

(74) Representative: Vossius & Partner Patentanwälte Rechtsanwälte mbB 
Siebertstrasse 3
81675 München
81675 München (DE)


(56) References cited: : 
EP-A1- 1 876 403
EP-A2- 1 270 292
US-A1- 2004 159 114
EP-A1- 1 970 651
JP-A- 2006 292 211
US-A1- 2007 204 635
   
       
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description


    [0001] The present invention relates to an air conditioner and a method for controlling the air conditioner, and more particularly, to an air conditioner, which detects refrigerant leak in real time, and a method for controlling the air conditioner.

    [0002] An air conditioner refers to a device for adjusting the condition of air to keep the air in a certain space in a condition which makes it comfortable to live in. Such an air conditioner functions to absorb heat within a certain space or release heat to the space so that the temperature and humidity of the space are kept at a proper level. The air conditioner of this type necessarily needs an indoor unit for absorbing heat within a certain space or releasing heat to the space.

    [0003] To detect refrigerant leak, it has been necessary for a service engineer to visit the site and comprehensively check the operation status of the air conditioner before detecting the refrigerant leak.

    [0004] EP 1 270 292 (A2) relates to a method for detecting refrigerant loss in a refrigerant circuit and cooling or air conditioning installation. US 2007/204635 (A1) relates to an air conditioning apparatus that judges normality or abnormality based on operation characteristics detected from the air conditioning apparatus at normal time and operation characteristics at the present. JP 2006 292211 (A) relates to accurately determine the suitability of the amount of refrigerants charged in a separate type air conditioner where the outdoor unit is connected to the indoor unit via a refrigerant communication pipe, even when an outdoor heat exchanger or an indoor heat exchanger ages. US 2004/159114 (A1) relates to a method of monitoring refrigerant level (filling amount of refrigerant) in a refrigerant circuit of an air-conditioning or heat-pump system with a compressor and a refrigerant operated in the supercritical range as a function of the operating point. EP 1 970 651 (A1) relates to a refrigerating air-conditioning system having a refrigerant leakage detection function, refrigerating air-conditioner, and method therefor. EP 1 876 403 (A1) relates to a function to judge the adequacy of the refrigerant quantity charged in a multi-type air conditioner in which a heat source unit and a plurality of utilization units are interconnected via refrigerant communication pipes.

    [0005] It is an object of the present invention to provide an air conditioner, which detects refrigerant leak in real time by self-monitoring, and a method for controlling the air conditioner.

    [0006] It is another object of the present invention to provide an air conditioner, which increases the accuracy of detection of refrigerant leak and prevents environmental contamination and additional failures caused by refrigerant leak, and a method for controlling the air conditioner.

    [0007] The objects of the present invention are not limited by the above-described objects, and other objects that are not mentioned will be apparent to those skilled in the art from the description that follows.

    [0008] To accomplish the above objects, there is provided a method for controlling an air conditioner as defined in independent claim 1.

    [0009] To accomplish the above objects, there is also provided an air conditioner according to independent claim 4.

    [0010] Details of other exemplary embodiments are included in the detailed description and drawings.

    [0011] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:

    FIG. 1 is a configuration diagram of an air conditioner according to an exemplary embodiment of the present invention;

    FIG. 2 is a block diagram of the air conditioner according to an exemplary embodiment of the present invention;

    FIG. 3 is a view showing a P-H diagram of the air conditioner according to an exemplary embodiment of the present invention; and

    FIG. 4 is a flowchart showing a method for controlling an air conditioner according to an exemplary embodiment of the present invention.



    [0012] Advantages and features of the present invention and methods of accomplishing the same will become apparent and more readily appreciated from the following description of the embodiments in conjunction with the accompanying drawings. The present invention may, however, may be embodied in many different forms, and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concept of the invention to those skilled in the art, and the present invention will only be defined by the appended claims. Like reference numerals refer to like elements throughout the specification.

    [0013] Hereinafter, an air conditioner and a method for controlling the air conditioner according to exemplary embodiments of the present invention will be described with reference to the drawings.

    [0014] FIG. 1 is a configuration diagram of an air conditioner according to an exemplary embodiment of the present invention.

    [0015] The air conditioner according to the exemplary embodiment of the present invention comprises an outdoor unit OU and a plurality of indoor units IUs.

    [0016] The outdoor unit OU comprises a compressor 110, an outdoor heat exchanger 140, an outdoor expansion valve 132, and a super cooler 180. The air conditioner may comprise one or a plurality of outdoor units OUs, and one outdoor unit OU is provided in this exemplary embodiment.

    [0017] The compressor 110 compresses an incoming low-temperature low-pressure refrigerant into a high-temperature high-pressure refrigerant. The compressor 110 may have various structures, and an inverter type compressor or constant-speed compressor may be employed. A discharge temperature sensor 171 and a discharge pressure sensor 151 are installed on a discharge pipe 161 of the compressor 110. A suction temperature sensor 175 and a suction pressure sensor 154 are installed on a suction pipe 168 of the compressor 110.

    [0018] The outdoor unit OU is shown to have one compressor 110, but without being limited thereto, the outdoor unit OU of the present invention may comprise a plurality of compressors, including both an inverter type compressor and a constant-speed compressor.

    [0019] An accumulator 187 may be installed at the suction pipe 168 of the compressor 110 to prevent a liquid refrigerant from being introduced into the compressor 110. Further, an oil separator 113 may be installed at the discharge pipe 161 of the compressor 110 to collect oil in the refrigerant discharged from the compressor 110.

    [0020] A four-way valve 160 is a flow switching valve to switch between cooling and heating operations. The four-way valve 160 guides the refrigerant, compressed by the compressor 110, to the outdoor heat exchanger 140 during the cooling operation, and to an indoor heat exchanger 120 during the heating operation. The four-way valve 160 is in an A state in the cooling operation, and is in a B state in the heating operation.

    [0021] The outdoor heat exchanger 140 is disposed in an outdoor space, and the refrigerant passing through the outdoor heat exchanger 140 exchanges heat with outdoor air. The outdoor heat exchanger 140 serves as a condenser in the cooling operation and serves as an evaporator in the heating operation.

    [0022] An outdoor outlet temperature sensor 179 is installed on an inlet pipe 166 connecting a liquid pipe 165 and the outdoor heat exchanger 140.

    [0023] The outdoor expansion valve 132 throttles the incoming refrigerant flow in the heating operation, and is installed on the inlet pipe 166. Further, a first bypass pipe 167 to allow the refrigerant to bypass the outdoor expansion valve 132 is installed on the inlet pipe 166, and a check valve 133 is installed on the first bypass pipe 167 to allow refrigerant to only flow in one direction. The check valve 133 causes the refrigerant to flow from the outdoor heat exchanger 140 to the plurality of indoor units IUs in the cooling operation, but shuts off the flow of the refrigerant in the heating operation.

    [0024] The supercooler 180 includes a supercooling heat exchanger 184, a second bypass pipe 181, a supercooling expansion valve 182, and a discharge pipe 185. The supercooling heat exchanger 184 is disposed on the inlet pipe 166. In the cooling operation, the second bypass pipe 181 serves to cause the refrigerant discharged from the supercooling heat exchanger 184 to be fed into the supercooling expansion valve 182.

    [0025] The supercooling expansion valve 182 is disposed on the second bypass pipe 181. The supercooling expansion valve 182 throttles the refrigerant flow in a liquid state fed into the second bypass pipe 181 to lower the pressure and temperature of the refrigerant, and then feeds the refrigerant in the low-pressure and low-temperature state into the supercooling heat exchanger 184. The supercooling expansion valve 182 may employ various types of valves, but the present embodiment employs a linear expansion valve for convenience of use. A supercooler inlet temperature sensor 177 to measure the temperature of the refrigerant throtteld by the supercooling expansion valve 182 may be installed on the second bypass pipe 181.

    [0026] During the cooling operation, the condensed refrigerant passing through the outdoor heat exchanger 140 is supercooled by exchanging heat with the refrigerant in the low-temperature state fed through the second bypass pipe 181 in the supercooling heat exchanger 184, and then is fed to the plurality of indoor units IUs.

    [0027] The refrigerant passing through the second bypass pipe 181 is fed to the accumulator 187 through the discharge pipe 185, after undergoing heat-exchange in the supercooling heat exchanger 184. A supercooler outlet temperature sensor 178 to measure the temperature of the refrigerant fed to the accumulator 187 is installed on the discharge pipe 185.

    [0028] A liquid pipe temperature sensor 174 and a liquid pipe pressure sensor 156 are installed on the liquid pipe 165 connecting the supercooler 180 and the plurality of indoor units IUs.

    [0029] In the air conditioner in accordance with an exemplary embodiment of the present invention, each of the plurality of indoor units IUs comprises an indoor heat exchanger 120, an indoor air blower 125, and an indoor expansion valve 131. The air conditioner may include one indoor unit IU or a plurality of indoor units IUs. In this exemplary embodiment, a plurality of IUs (1 to n) are provided.

    [0030] The indoor heat exchanger 120 is disposed in an indoor space, and the refrigerant passing through the indoor heat exchanger 120 exchanges heat with indoor air. The indoor heat exchanger 120 serves as an evaporator in the cooling operation, and serves as a condenser in the heating operation.

    [0031] The indoor air blower 125 blows indoor air that undergoes heat exchange in the indoor heat exchanger 120.

    [0032] The indoor expansion valve 131 throttles the incoming refrigerant flow in the cooling operation. The indoor expansion valve 131 is installed on an indoor inlet pipe 163 of the indoor unit IU. The indoor expansion valve 131 may employ various types of valves, but the present embodiment employs a linear expansion valve for convenience of use.

    [0033] Preferably, the indoor expansion valve 131 is opened to a set opening degree during the cooling operation, and is completely opened during the heating operation. The indoor expansion valve 131 may be closed during the blowing operation. Here, the closing of the indoor expansion valve 131 does not mean complete physical closing, but means an opening degree of the indoor expansion valve 131 such that the refrigerant does not flow through the indoor expansion valve 131. The indoor expansion valve 131 may be closed or opened in order to detect a malfunction.

    [0034] An indoor inlet pipe temperature sensor 173 may be installed on the indoor inlet pipe 163. The indoor inlet pipe temperature sensor 173 may be installed between the indoor heat exchanger 120 and the indoor expansion valve 131. Further, an indoor outlet pipe temperature sensor 172 may be installed on an indoor outlet pipe 164.

    [0035] The flow of the refrigerant during the cooling operation of the above-described air conditioner is as follows.

    [0036] The refrigerant in a high-temperature and high-pressure vapor state discharged from the compressor 110 is fed into the outdoor heat exchanger 140 via the four-way valve 160. In the outdoor heat exchanger 140, the refrigerant exchanges heat with the outdoor air, thus being condensed. The refrigerant discharged from the outdoor heat exchanger 140 is fed to the supercooler 180 through the completely open outdoor expansion valve 132 and the bypass pipe 133. The refrigerant fed to the supercooler 180 is supercooled by the supercooling heat exchanger 184, and then is fed to the plurality of indoor units IUs.

    [0037] A part of the refrigerant supercooled by the supercooling heat exchanger 184 is throttled by the supercooling expansion valve 182 to supercool the refrigerant passing through the supercooling heat exchanger 184. A part of the refrigerant supercooled by the supercooling heat exchanger 184 is fed to the accumulator 187.

    [0038] The refrigerant fed to each of the indoor units IUs is throttled by the indoor expansion valve 131 that is open to a set opening degree, and the refrigerant is then evaporated by exchanging heat with the indoor air in the indoor heat exchanger 120. The evaporated refrigerant is then fed into the compressor 110 via the four-way valve 160 and the accumulator 187.

    [0039] The flow of the refrigerant during the heating operation of the above-described air conditioner is as follows.

    [0040] The refrigerant in a high-temperature and high-pressure vapor state discharged from the compressor 110 is fed into the plurality of indoor units IUs via the four-way valve 160. The indoor expansion valve 131 of each of the plurality of indoor units IUs is completely open. Therefore, the refrigerant fed from the indoor units IUs is throttled by the outdoor expansion valve 132, and then is evaporated by exchanging heat with outdoor air in the outdoor heat exchanger 140. The evaporated refrigerant is then fed into the suction pipe 168 of the compressor 110 via the four-way valve 160 and the accumulator 187.

    [0041] FIG. 2 is a block diagram of the air conditioner according to an exemplary embodiment of the present invention.

    [0042] The discharge temperature sensor 171 measures the temperature of the refrigerant discharged from the compressor 110. The discharge temperature sensor 171 is installed on the discharge pipe 161 of the compressor 110. A control unit 190 determines through the discharge temperature sensor 171 whether or not a high-pressure condensation temperature has a normal value in a normal operating state.

    [0043] The indoor outlet pipe temperature sensor 172 measures the temperature of the refrigerant discharged from the indoor heat exchanger 120. The indoor outlet pipe temperature sensor 172 is installed on the indoor outlet pipe 164. The control unit 190 determines through the indoor outlet pipe temperature sensor 172 whether or not a low-pressure evaporation temperature is normal in the normal operating state.

    [0044] The indoor inlet pipe temperature sensor 173 measures the temperature of the refrigerant fed to the indoor heat exchanger 120. The indoor inlet pipe temperature sensor 173 is installed on the indoor inlet pipe 163 connecting the indoor heat exchanger 120 and the indoor expansion valve 131.

    [0045] The control unit 190 determines through the indoor inlet pipe temperature sensor 173 whether or not an indoor inlet pipe temperature is normal in the normal operating state. Further, the control unit 190 calculates the difference between a temperature measured by the indoor outlet pipe temperatures sensor 172 and a temperature measured by the indoor inlet pipe temperature sensor 173 to determine whether or not the superheating degree of the indoor heat exchanger is normal in the normal operating state.

    [0046] The liquid pipe temperature sensor 174 measures the temperature of the refrigerant flowing between the supercooler 180 and the indoor heat exchanger 120. The liquid pipe temperature sensor 174 is installed on the liquid pipe 165 connecting the supercooler 180 and the indoor units IUs. The control unit 190 determines through the liquid pipe temperature sensor 174 whether or not a liquid pipe temperature is normal in the normal operating state.

    [0047] The suction temperature sensor 175 measures the temperature of the refrigerant sucked into the compressor 110. The suction temperature sensor 175 is installed on the suction pipe 168 of the compressor 110. The control unit 190 determines through the suction temperature sensor 175 whether or not a suction temperature is normal in the normal operating state.

    [0048] The supercooler inlet temperature sensor 177 measures the temperature of the refrigerant throttled for supercooling in the supercooler 180. The supercooler inlet temperature sensor 177 is installed on the second bypass pipe 181. The supercooler outlet temperature sensor 178 measures the temperature of the refrigerant heat-exchanged after being throttled for supercooling in the supercooler 180. The supercooler outlet temperature sensor 178 is installed on the discharge pipe 185. The control unit 190 calculates the difference between a temperature measured by the supercooler inlet temperature sensor 177 and a temperature measured by the supercooler outlet temperature sensor 178 to determine whether or not the superheating degree of a supercooling circuit is normal in the normal operating state.

    [0049] The outdoor outlet temperature sensor 179 measures the temperature of the refrigerant to be condensed in the outdoor heat exchanger 140 during the cooling operation or to be evaporated in the outdoor heat exchanger 140 during the heating operation. The outdoor outlet temperature sensor 179 is installed on the inlet pipe 166. The control unit 190 determines through the outdoor outlet temperature sensor 179 whether or not an outdoor heat exchanger outlet temperature is normal in the normal operating state.

    [0050] An opening degree of the indoor expansion valve 131 is transmitted to the control unit 190 so that the control unit 190 determines whether or not the opening degree of the indoor expansion valve is normal in the normal operating state.

    [0051] An opening degree of the supercooling expansion valve 182 is transmitted to the control unit 190 so that the control unit 190 determines whether or not the opening degree of the supercooling expansion valve is normal in the normal operating state.

    [0052] The high-pressure pressure sensor 151 measures the pressure of the refrigerant discharged from the compressor 110. The high-pressure sensor 151 is installed on the discharge pipe 161 of the compressor 110. The control unit 190 determines through the high-pressure sensor 151 whether or not a discharge superheating degree has a normal value in the normal operating state by calculating the saturation temperature of the discharged refrigerant and calculating the difference with the discharge temperature measured by the discharge temperature sensor 171.

    [0053] The low-pressure sensor 154 measures the pressure of the refrigerant sucked into the compressor 110. The low-pressure sensor 154 is installed on the suction pipe 162 of the compressor 110. The control unit 190 determines through the low-pressure sensor 154 whether or not a suction superheating degree is normal in the normal operating state by calculating the saturation temperature of the sucked refrigerant and calculating the difference with the suction temperature measured by the suction temperature sensor 175.

    [0054] The liquid pipe pressure sensor 156 measures the pressure of the refrigerant flowing between the supercooler 180 and the indoor heat exchanger 120. The liquid pipe pressure sensor 156 is installed on the liquid pipe 165 connecting the supercooler 180 and the indoor unit IU. The control unit 190 determines through the liquid pipe pressure sensor 156 whether or not a supercooling degree is normal in the normal operating state by calculating the saturation temperature of the supercooled refrigerant and calculating the difference with the liquid temperature measured by the liquid pipe temperature sensor 174.

    [0055] The control unit 190 tracks a cycle change from operating variables measured in real time in the normal operating state to detect refrigerant leak from the cycle change. The operating variables include a discharge superheat degree at the discharge side of the compressor and may further include at least one of a suction superheating degree, an indoor inlet pipe temperature, a suction temperature, a condensation temperature, an evaporation temperature, a supercooling temperature, a liquid pipe temperature, the opening degree of the superheating expansion valve, the overheating degree of the supercooling circuit, the superheating degree of the indoor heat exchanger, and an outdoor heat exchanger outlet temperature. The normal operating state refers to a state where a general cooling or heating operation is performed normally by superheating degree control, rather than by start-up control or by direct control of the outdoor unit.

    [0056] The control unit 190 tracks a change in cooling cycle or heating cycle from a change on a Pressure Enthalpy(P-H) diagram (Mollier diagram). Upon detecting refrigerant leak, the control unit 190 transmits the detection result to the display unit 192 or the communication unit 194 to notify the outside of this detection result.

    [0057] The display unit 192 externally displays result of the detecting the refrigerant leak. The display unit 192 can aurally or visually represent refrigerant leak, preferably, visually displays the refrigerant leak by 7 segment or LED.

    [0058] The communication unit 194 externally transmits result of the detecting the refrigerant leak via a network. The communication unit 194 transmits the result of the detecting the refrigerant leak to a control center or the terminal of a service engineer at a distance via the network and displays it.

    [0059] FIG. 3 is a view showing a P-H diagram of the air conditioner according to the present invention.

    [0060] In the P-H diagram, the cycle obtained at a normal refrigerant amount and the cycle obtained during refrigerant leak are different. Referring to FIG. 3, a method of determining the normality of a discharge superheating degree will be discussed. In FIG. 3, the discharge superheating degree at the normal refrigerant amount is T1, and the discharge superheating degree during the refrigerant leak is T2. That is, the normal value of the discharge superheating degree is T1.

    [0061] The control unit 190 tracks whether or not the discharge superheating degree is T2 in the normal operating state to detect refrigerant leak.

    [0062] FIG. 4 is a flowchart showing a method for controlling an air conditioner according to an exemplary embodiment of the present invention.

    [0063] Operating variables are measured in the normal operating state (S210). The operating variables include a discharge superheat degree at the discharge side of the compressor and may further include at least one of a suction superheating degree, an indoor inlet pipe temperature, a suction temperature, a condensation temperature, an evaporation temperature, a supercooling temperature, a liquid pipe temperature, the opening degree of the superheating expansion valve, the overheating degree of the supercooling circuit, the superheating degree of the indoor heat exchanger, and an outdoor heat exchanger outlet temperature. The normal operating state refers to a state where a general cooling operation is performed normally by means of superheating degree control, rather than by means of start-up control or direct control of the outdoor unit.

    [0064] A cycle change is tracked from the operating variables to detect refrigerant leak (S220). The control unit 190 determines normality by tracking a change in cooling cycle from a change on the P-H diagram.

    [0065] If refrigerant leak is detected, it is determined whether or not a self-supercooling degree of the outdoor heat exchanger attains a reference value (S230). The self-supercooling degree of the outdoor heat exchanger is the difference between a condensation temperature measured by the discharge temperature sensor 171 and an outdoor heat exchanger outlet temperature measured by the outdoor outlet temperature sensor 179. If there is any refrigerant left in the accumulator 187, this can be considered as refrigerant leak, and therefore the control unit 190 determines whether or not the self-supercooling degree of the outdoor heat exchanger attains the reference value.

    [0066] If the self-supercooling degree of the outdoor heat exchanger attains the reference value, the control unit 190 measures the operating variables again in the normal operating state (S270).

    [0067] If the self-supercooling degree of the outdoor heat exchanger does not attain the reference value, a target superheating degree of the indoor heat exchanger is increased (S240). The superheating degree of the indoor heat exchanger is the difference between a temperature measured by the indoor outlet pipe temperature sensor 172 and a temperature measured by the indoor inlet pipe temperature sensor 173. The control unit 190 increases the target superheating degree of the indoor heat exchanger to empty the refrigerant left in the accumulator 187.

    [0068] After increasing the target superheating degree of the indoor heat exchanger, the timer is increased (S250), and the control unit 190 determines if the timer exceeds a reference time (S260). If the timer does not exceed the reference time, the control unit 190 determines whether or not the self-supercooling degree of the outdoor heat exchanger attains the reference value (S230).

    [0069] If the timer exceeds the reference time, the operating variables are measured again in the normal operating state (S270), and a cycle change is tracked from the operating variables to detect t refrigerant leak again (S280). The control unit 190 increases accuracy by detecting the refrigerant leak once again.

    [0070] If refrigerant leak is detected, a refrigerant leak state is displayed or transmitted (S290). Upon detecting refrigerant leak, the control unit 190 transmits the detection result to the display unit 192 or the communication unit 194 to represent result of the detecting refrigerant leak. The display unit 192 externally displays the result of the detecting refrigerant leak. The communication unit 194 externally transmits the result of the detecting refrigerant leak via a network.

    [0071] According to the air conditioner and the method for controlling the air conditioner of the present invention, one or more of the following effects can be observed.

    [0072] First, refrigerant leak can be detected in real time by self-monitoring of the air conditioner.

    [0073] Second, the accuracy of detection of refrigerant leak of the air conditioner can be increased.

    [0074] Third, refrigerant leak of the air conditioner can be quickly detected, thereby preventing additional failures and minimizing environmental contamination.


    Claims

    1. A method for controlling an air conditioner, wherein the air conditioner comprises an outdoor unit having a compressor, an outdoor heat exchanger and a supercooler and an indoor unit having an indoor heat exchanger, the method comprising:

    during normal cooling operation, tracking a cycle change from a discharge superheat degree at the discharge side of the compressor of the air conditioner (S220), wherein the normal cooling operation refers to a state where a cooling operation is performed by means of superheating degree control,

    detecting refrigerant leak from the cycle change based on the discharge superheating degree, wherein the cycle change is a change on a Pressure Enthalpy, P-H, diagram, wherein in the P-H diagram, the cycle obtained at a normal refrigerant amount and the cycle obtained during refrigerant leak is different, wherein the discharge superheating degree (T1) at the normal refrigerant amount and the discharge superheating degree (T2) during the refrigerant leak is different,

    determining whether or not a self-supercooling degree of the outdoor heat exchanger attains a reference value when refrigerant leak is detected (S230);

    wherein the self-supercooling degree of the outdoor heat exchanger is a difference between a temperature of refrigerant discharged from the compressor and a temperature of refrigerant at the outlet of the outdoor heat exchanger;

    increasing a target superheating degree of the indoor heat exchanger of the air conditioner when the self-supercooling degree does not attain the reference value (S240); and

    detecting refrigerant leak again (S280); and

    representing the result of the detecting refrigerant leak (S290).


     
    2. The method of claim 1, wherein the result of the detecting refrigerant leak is displayed on the air conditioner.
     
    3. The method of claim 1 or 2, wherein the result of the detecting refrigerant leak is transmitted via a network.
     
    4. An air conditioner, comprising:

    an outdoor unit having a compressor (110) for compressing refrigerant, a heat exchanger (140) connected to the compressor for condensing refrigerant and exchanging heat with outdoor air and a supercooler (180);

    an indoor unit having a heat exchanger (120) connected to the outdoor unit and for exchanging heat with indoor air;

    an outdoor outlet temperature sensor (179) for measuring a temperature of refrigerant to be condensed in the outdoor heat exchanger;

    a discharge temperature sensor (171) for measuring a temperature of refrigerant discharged from the compressor; and

    a control unit (190) configured to track, during normal cooling operation, a cycle change from a discharge superheat degree at the discharge side of the compressor,

    wherein the normal cooling operation refers to a state where a cooling operation is performed by means of superheating degree control,

    wherein the control unit is configured to detect refrigerant leak from the cycle change based on the discharge superheating degree, wherein in the P-H diagram, the cycle obtained at a normal refrigerant amount and the cycle obtained during refrigerant leak is different, wherein the discharge superheating degree (T1) at the normal refrigerant amount and the discharge superheating degree (T2) during the refrigerant leak is different,

    wherein the control unit is configured to:

    determine whether or not a self-supercooling degree of the outdoor heat exchanger attains a reference value,

    wherein the control unit is configured to increase a target superheating degree of the indoor heat exchanger of the air conditioner when the self-supercooling degree does not attain the reference value, wherein the self-supercooling degree of the outdoor heat exchanger is a difference between the temperature measured by the discharge temperature sensor and the temperature at the outlet of the outdoor temperature sensor,

    detect refrigerant leak again, and

    represent the result of the detecting refrigerant leak.


     
    5. The air conditioner of claim 4, further comprising a display unit (192) for displaying the refrigerant leak detected by the control unit.
     
    6. The air conditioner of claim 4 or 5, further comprising a communication unit (194) for transmitting result of the refrigerant leak detected by the control unit via a network.
     


    Ansprüche

    1. Verfahren zum Steuern einer Klimaanlage, wobei die Klimaanlage eine Außeneinheit mit einem Verdichter, einem Außenwärmetauscher und einem Unterkühler und eine Inneneinheit mit einem Innenwärmetauscher aufweist, wobei das Verfahren aufweist:

    während des normalen Kühlbetriebs, Verfolgen einer Zyklusänderung von einem Ausstoßüberhitzungsgrad an der Ausstoßseite des Verdichters der Klimaanlage (S220), wobei sich der normale Kühlbetrieb auf einen Zustand bezieht, in dem ein Kühlbetrieb mittels einer Überhitzungsgradsteuerung durchgeführt wird,

    Ermitteln eines Kältemittellecks aus der Zyklusänderung basierend auf dem Ausstoßüberhitzungsgrad, wobei die Zyklusänderung eine Änderung in einem Druck-Enthalpie-Diagramm (P-H-Diagramm) ist, wobei sich im P-H-Diagramm der Zyklus, der bei einer normalen Kältemittelmenge erhalten wird, und der Zyklus unterscheiden, der während eines Kältemittellecks erhalten wird, wobei sich der Ausstoßüberhitzungsgrad (T1) bei der normalen Kältemittelmenge und der Ausstoßüberhitzungsgrad (T2) während des Kältemittellecks unterscheiden,

    Bestimmen, ob ein Selbstunterkühlungsgrad des Außenwärmetauschers einen Referenzwert erreicht oder nicht, wenn ein Kältemittelleck ermittelt wird (S230);

    wobei der Selbstunterkühlungsgrad des Außenwärmetauschers eine Differenz zwischen einer Temperatur des vom Verdichter abgegebenen Kältemittels und einer Temperatur des Kältemittels am Auslass des Außenwärmetauschers ist;

    Erhöhen eines Zielüberhitzungsgrades des Innenwärmetauschers der Klimaanlage, wenn der Selbstunterkühlungsgrad nicht den Referenzwert (S240) erreicht; und

    erneutes Ermitteln eines Kältemittellecks (S280); und

    Darstellen des Ergebnisses des Ermittelns eines Kältemittellecks (S290).


     
    2. Verfahren nach Anspruch 1, wobei das Ergebnis des Ermittelns eines Kältemittellecks an der Klimaanlage angezeigt wird.
     
    3. Verfahren nach Anspruch 1 oder 2, bei dem das Ergebnis des Ermittelns eines Kältemittellecks über ein Netzwerk übertragen wird.
     
    4. Klimaanlage, die aufweist:

    eine Außeneinheit mit einem Verdichter (110) zum Verdichten von Kältemittel, einem Wärmetauscher (140), der mit dem Verdichter verbunden ist, um Kältemittel zu kondensieren und Wärme mit Außenluft auszutauschen, und einem Unterkühler (180);

    eine Inneneinheit mit einem Wärmetauscher (120), der mit der Außeneinheit verbunden ist, um Wärme mit der Innenluft zu tauschen;

    einen Außenauslass-Temperatursensor (179) zum Messen einer Temperatur des im Außenwärmetauscher zu kondensierenden Kältemittels;

    einen Ausstoßtemperatursensor (171) zum Messen einer Temperatur des vom Verdichter ausgestoßenen Kältemittels; und

    eine Steuereinheit (190), die konfiguriert ist, während des normalen Kühlbetriebs einen Zykluswechsel von einem Ausstoßüberhitzungsgrad an der Ausstoßseite des Verdichters zu verfolgen,

    wobei sich der normale Kühlbetrieb auf einen Zustand bezieht, in dem ein Kühlbetrieb mittels einer Überhitzungsgradsteuerung durchgeführt wird,

    wobei die Steuereinheit konfiguriert ist, ein Kältemittelleck aus der Zyklusänderung basierend auf dem Ausstoßüberhitzungsgrad zu ermitteln, wobei sich im P-H-Diagramm der Zyklus, der bei einer normalen Kältemittelmenge erhalten wird, und der Zyklus unterscheiden, der während des Kältemittellecks erhalten wird, wobei sich der Ausstoßüberhitzungsgrad (T1) bei der normalen Kältemittelmenge und der Ausstoßüberhitzungsgrad (T2) während des Kältemittellecks unterscheiden,

    wobei die Steuereinheit konfiguriert ist:

    zu bestimmen, ob ein Selbstunterkühlungsgrad des Außenwärmetauschers einen Referenzwert erreicht oder nicht,

    wobei die Steuereinheit konfiguriert ist, einen Zielüberhitzungsgrad des Innenraum-Wärmetauschers der Klimaanlage zu erhöhen, wenn der Selbst-Unterkühlungsgrad den Referenzwert nicht erreicht, wobei der Selbstunterkühlungsgrad des Außenwärmetauschers eine Differenz zwischen der vom Ausstoßtemperatursensor gemessenen Temperatur und der Temperatur am Auslass des Außen-Temperatursensors ist,

    ein Kältemittellecks erneut zu ermitteln, und

    das Ergebnis des Ermittelns eines Kältemittellecks zu repräsentieren.


     
    5. Klimaanlage nach Anspruch 4, die ferner eine Anzeigeeinheit (192) zum Anzeigen des von der Steuereinheit ermittelten Kältemittellecks aufweist.
     
    6. Klimaanlage nach Anspruch 4 oder 5, die ferner eine Kommunikationseinheit (194) aufweist, um das Ergebnis des von der Steuereinheit ermittelten Kältemittellecks über ein Netzwerk zu übertragen.
     


    Revendications

    1. Procédé de commande d'un climatiseur, ledit climatiseur comprenant une unité extérieure ayant un compresseur, un échangeur de chaleur extérieur et un sur-refroidisseur, et une unité intérieure ayant un échangeur de chaleur intérieur, ledit procédé comprenant :

    pendant un processus de refroidissement normal, le suivi d'un changement de cycle à partir d'un degré de surchauffe de refoulement sur le côté refoulement du compresseur du climatiseur (S220), le processus de refroidissement normal se rapportant à un état où un processus de refroidissement est exécuté au moyen d'une commande de degré de surchauffe,

    la détection d'une fuite de réfrigérant à partir du changement de cycle sur la base du degré de surchauffe de refoulement, ledit changement de cycle étant un changement sur un diagramme pression-enthalpie, P-H, où, dans le diagramme P-H, le cycle obtenu à une quantité normale de réfrigérant et le cycle obtenu pendant la fuite de réfrigérant sont différents, le degré de surchauffe de refoulement (T1) à la quantité normale de réfrigérant et le degré de surchauffe de refoulement (T2) pendant la fuite de réfrigérant étant différents,

    la détermination si un degré d'auto-surrefroidissement de l'échangeur de chaleur extérieur atteint ou non une valeur de référence lorsqu'une fuite de réfrigérant est détectée (S230) ;

    où le degré d'auto-surrefroidissement de l'échangeur de chaleur extérieur est une différence entre une température du réfrigérant refoulé par le compresseur et une température du réfrigérant à la sortie de l'échangeur de chaleur extérieur ;

    l'augmentation d'un degré de surchauffe de consigne de l'échangeur de chaleur intérieur du climatiseur si le degré d'auto-surrefroidissement n'atteint pas la valeur de référence (S240) ; et

    un nouvelle détection d'une fuite de réfrigérant (S280) ; et

    la représentation du résultat de détection de fuite de réfrigérant (S290).


     
    2. Procédé selon la revendication 1, où le résultat de détection de fuite de réfrigérant est affiché sur le climatiseur.
     
    3. Procédé selon la revendication 1 ou la revendication 2, où le résultat de détection de fuite de réfrigérant est transmis sur un réseau.
     
    4. Climatiseur, comprenant :

    une unité extérieure ayant un compresseur (110) pour comprimer le réfrigérant, un échangeur de chaleur (140) relié au compresseur pour condenser le réfrigérant et échanger de la chaleur avec l'air extérieur, et un sur-refroidisseur (180) ;

    une unité intérieure ayant un échangeur de chaleur (120) relié à l'unité extérieure et permettant d'échanger de la chaleur avec l'air intérieur ;

    un capteur de température de sortie extérieure (179) pour mesurer une température du réfrigérant à condenser dans l'échangeur de chaleur extérieur ;

    un capteur de température de refoulement (171) pour mesurer une température du réfrigérant refoulé par le compresseur ; et

    une unité de commande (190) prévue pour suivre, pendant un processus de refroidissement normal, un changement de cycle à partir d'un degré de surchauffe de refoulement sur le côté refoulement du compresseur,

    le processus de refroidissement normal se rapportant à un état où un processus de refroidissement est exécuté au moyen d'une commande de degré de surchauffe,

    où l'unité de commande est prévue pour détecter une fuite de réfrigérant à partir du changement de cycle sur la base du degré de surchauffe de refoulement, où, dans le diagramme P-H, le cycle obtenu à une quantité normale de réfrigérant et le cycle obtenu pendant la fuite de réfrigérant sont différents, le degré de surchauffe de refoulement (T1) à la quantité normale de réfrigérant et le degré de surchauffe de refoulement (T2) pendant la fuite de réfrigérant étant différents,

    où l'unité de commande est prévue pour :

    déterminer si un degré d'auto-surrefroidissement de l'échangeur de chaleur extérieur atteint ou non une valeur de référence,

    l'unité de commande étant prévue pour augmenter un degré de surchauffe de consigne de l'échangeur de chaleur intérieur du climatiseur si le degré d'auto-surrefroidissement n'atteint pas la valeur de référence, le degré d'auto-surrefroidissement de l'échangeur de chaleur extérieur étant une différence entre la température mesurée par le capteur de température de refoulement et la température à la sortie du capteur de température extérieur,

    détecter à nouveau une fuite de réfrigérant, et

    représenter le résultat de détection de fuite de réfrigérant.


     
    5. Climatiseur selon la revendication 4, comprenant en outre une unité d'affichage (192) pour afficher la fuite de réfrigérant détectée par l'unité de commande.
     
    6. Climatiseur selon la revendication 4 ou la revendication 5, comprenant en outre une unité de communication (194) pour transmettre le résultat de fuite de réfrigérant détectée par l'unité de commande sur un réseau.
     




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    Cited references

    REFERENCES CITED IN THE DESCRIPTION



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    Patent documents cited in the description