CN110836519B - Air conditioner refrigerant leakage detection method and detection system - Google Patents

Air conditioner refrigerant leakage detection method and detection system Download PDF

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CN110836519B
CN110836519B CN201810934931.7A CN201810934931A CN110836519B CN 110836519 B CN110836519 B CN 110836519B CN 201810934931 A CN201810934931 A CN 201810934931A CN 110836519 B CN110836519 B CN 110836519B
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air conditioner
refrigerant
compressor
current
refrigerant leakage
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CN110836519A (en
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白韡
许真鑫
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Aux Air Conditioning Co Ltd
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Aux Air Conditioning Co Ltd
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/62—Control or safety arrangements characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
    • F24F11/63—Electronic processing
    • F24F11/65—Electronic processing for selecting an operating mode
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
    • F24F11/32—Responding to malfunctions or emergencies
    • F24F11/36—Responding to malfunctions or emergencies to leakage of heat-exchange fluid
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/70—Control systems characterised by their outputs; Constructional details thereof
    • F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
    • F24F11/83—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers
    • F24F11/84—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers using valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/70—Control systems characterised by their outputs; Constructional details thereof
    • F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
    • F24F11/86—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling compressors within refrigeration or heat pump circuits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/89—Arrangement or mounting of control or safety devices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F2110/00—Control inputs relating to air properties
    • F24F2110/10—Temperature
    • F24F2110/12—Temperature of the outside air

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Physics & Mathematics (AREA)
  • Fuzzy Systems (AREA)
  • Mathematical Physics (AREA)
  • Thermal Sciences (AREA)
  • Air Conditioning Control Device (AREA)

Abstract

The invention provides a method and a system for detecting refrigerant leakage of an air conditioner, comprising the following steps: judging whether the air conditioner operates normally according to the current load index of the air conditioner, if so, continuing normal operation of the air conditioner, and if not, acquiring the current operation mode of the air conditioner and executing a refrigerant judgment program; when the current operation mode of the air conditioner is a heating mode, judging whether the air conditioner has refrigerant leakage or not according to the outdoor environment temperature, the continuous operation time of the compressor and the opening degree of the expansion valve; when the current operation mode of the air conditioner is a refrigeration mode or a dehumidification mode, the circulation change is tracked from the refrigerant circulation process of the air conditioner, the refrigerant leakage is detected from the circulation change, and when the refrigerant leaks, the leakage position of the refrigerant is judged according to the change rate of the compressor power along with the time. The detection method provided by the invention can accurately judge whether the refrigerant leakage occurs on the indoor unit or the outdoor unit, is convenient for maintenance personnel to maintain and improves the maintenance efficiency.

Description

Air conditioner refrigerant leakage detection method and detection system
Technical Field
The invention relates to the technical field of air conditioners, in particular to a method and a system for detecting refrigerant leakage of an air conditioner.
Background
The existing air-conditioning refrigeration system comprises a compressor, an outdoor heat exchanger, a throttling device, an indoor heat exchanger, a certain amount of refrigerant which is filled in advance and the like. And under the condition that the refrigerant is not leaked, the air conditioning system can normally perform refrigeration operation. If the air conditioner is not installed normally or the refrigerant in the system pipeline slowly leaks for a long time due to vibration and other reasons during later operation, the refrigeration effect of the air conditioning system is deteriorated. When the refrigerant leakage is serious, the compressor is often burnt. Therefore, it is necessary to detect the leakage of the refrigerant in the air conditioner. When the air conditioner in the prior art judges the refrigerant leakage, the judging method is simple, the phenomenon of misjudgment is easy to occur, and the refrigerant leakage can not be accurately judged whether to occur in an indoor unit or an outdoor unit, so that the maintenance pressure is increased.
Disclosure of Invention
In view of the above, the present invention is directed to a method and a system for detecting refrigerant leakage of an air conditioner. The method solves the problems that when the air conditioner performs refrigerant leakage judgment in the prior art, the judgment method is simple, misjudgment is easy to occur, and whether refrigerant leakage occurs in an indoor unit or an outdoor unit cannot be accurately judged.
In order to achieve the purpose, the technical scheme of the invention is realized as follows:
a method for detecting the leakage of refrigerant of an air conditioner comprises the following steps:
s1, judging whether the air conditioner operates normally according to the current load index of the air conditioner, if so, continuing normal operation of the air conditioner, and if not, acquiring the current operation mode of the air conditioner and executing a refrigerant judgment program;
s2, when the current operation mode of the air conditioner is a heating mode, judging whether the air conditioner has refrigerant leakage according to the outdoor environment temperature, the continuous operation time of the compressor and the opening degree of the expansion valve;
s3, when the current operation mode of the air conditioner is a refrigeration mode or a dehumidification mode, tracking the circulation change from the refrigerant circulation process of the air conditioner, detecting the refrigerant leakage from the circulation change, and judging the time-dependent change rate (delta W/delta t) of the current input power of the compressor when the refrigerant leaks1And whether a second preset condition is met or not is judged, if yes, the indoor unit is judged to have refrigerant leakage, and if not, the outdoor unit is judged to have refrigerant leakage.
Further, the S1 includes the following steps:
s11, detecting the current load index of the air conditioner, wherein the load index of the air conditioner is the current overall machine input current I of the air conditionera；
S12, judging the current input current I of the whole machineaWhether or not it is less than the first current threshold I1If yes, the refrigerant leakage possibility is high, step S13 is executed, otherwise, the refrigerant is not leakedThe air conditioner normally operates in the current state;
s13, restarting the air conditioner, judging whether the compressor is in the running state, if so, executing a step S2; if not, the refrigerant determination program is not executed.
Further, the S2 includes the following steps:
s21, detecting the outdoor environment temperature KOuter coverAnd compressor continuous run time Ta;
s22, judging whether the running state of the compressor reaches a first preset condition, if so, executing a step S23;
the first preset condition is; continuous running time T of compressoraIs longer than the first preset time T1And the outdoor ambient temperature KOuter coverGreater than a set temperature K0；
And S23, judging that the opening degree of the expansion valve is larger than a first set threshold value, if so, judging that the refrigerant leaks, and if not, judging that the refrigerant does not leak.
Further, the S3 includes the following steps:
s31, judging the continuous operation time T of the compressorbWhether the second preset time T is reached2If yes, executing step S32, otherwise, continuing normal operation of the compressor until reaching the second preset time T2；
S32, measuring the operation variables of the air conditioner in the current operation state to obtain a circulation process diagram L in the current operation state1；
S33, judging refrigerant circulation process diagram L under current operation state1And whether the refrigerant circulation process diagram L in the normal state is satisfied0If yes, go to step S34, otherwise go to step S35;
s34, starting a refrigerant leakage prevention program;
s35, judging the exhaust temperature T of the compressordTemperature T of inlet air of outdoor heat exchangercIf the third preset condition is met, executing a step S36 to enter a refrigerant leakage verification program if the third preset condition is met, and controlling the compressor to continue to operate if the third preset condition is not met;
the third preset condition is Td＞A+B*TcAnd A, B is a predetermined constant.
Further, the S36 includes the following steps:
s361, detecting the time-varying rate (delta W/delta t) of the input power of the compressor1；
S362, judging the time-dependent change rate (delta W/delta t) of the current input power of the compressor1And if the change rate is larger than the preset change rate threshold K, judging that the indoor unit has refrigerant leakage, and if not, judging that the outdoor unit has refrigerant leakage.
Further, the refrigerant pipeline leakage-prevention detection program comprises the following steps:
s341, detecting the vibration frequency of the refrigerant pipeline;
and S342, judging whether the vibration frequency of the refrigerant pipeline is in the resonance frequency range of the compressor, if so, adjusting the operation frequency of the compressor, and if not, ending the process.
Further, the operating variable includes at least one of an indoor inlet pipe temperature, a suction temperature, a liquid pipe temperature, a compressor discharge pressure, a compressor suction pressure, and an outdoor heat exchanger outlet temperature.
Further, the first current threshold I1When the refrigerant quantity of the air conditioner is equal to the standard refrigerant quantity, the current is input into the compressor under the minimum load.
Compared with the prior art, the air conditioner refrigerant leakage detection method has the following advantages:
the method for detecting the refrigerant leakage of the air conditioner can detect the air conditioner in different operation modes, can accurately judge whether the refrigerant leakage occurs on the indoor unit or the outdoor unit, is convenient for maintenance personnel to maintain in a targeted manner, and improves the maintenance efficiency. Moreover, the refrigerant leakage judging program provided by the embodiment has higher accuracy through multi-stage judgment, reduces the misjudgment rate, and avoids the situations that the motor in the compressor is overheated, the compressor is damaged, safety accidents are caused and the like due to refrigerant leakage.
The invention also provides a refrigerant leakage detection system, which comprises:
the acquisition module is used for acquiring the complete machine input current and the operation mode of the air conditioner and the operation time and the input power of the compressor;
the control module is used for controlling the on-off and the running state of the compressor and controlling and starting a leakage-proof program of the refrigerant pipeline;
and the detection module is used for detecting the temperature of an indoor inlet pipe of the air conditioner, the exhaust temperature of the compressor, the outdoor environment temperature, the air inlet temperature of the outdoor heat exchanger and the vibration frequency of the refrigerant pipeline and the compressor.
Further, the detection module comprises a temperature sensor and a pressure sensor, the temperature sensor is respectively arranged on a connecting pipe of the indoor heat exchanger and the indoor expansion valve, a suction pipe of the compressor, the subcooler, a connecting pipe of the indoor unit and an outlet of the outdoor heat exchanger, and the pressure sensor is arranged on a discharge pipe and a suction pipe of the compressor in decibel.
Compared with the prior art, the air conditioner refrigerant leakage detection system and the air conditioner refrigerant leakage detection method have the same advantages, and are not repeated herein.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 is a flow chart of a method for detecting refrigerant leakage of an air conditioner according to an embodiment of the present invention;
FIG. 2 is a diagram illustrating a refrigerant cycle process according to an embodiment of the present invention;
fig. 3 is a flow chart of a first step in the method for detecting refrigerant leakage of an air conditioner according to the embodiment of the present invention;
fig. 4 is a flow chart of a refrigerant leakage detection method in a heating mode of an air conditioner according to an embodiment of the present invention;
FIG. 5 is a flow chart illustrating a method for detecting refrigerant leakage in a cooling or dehumidifying mode of an air conditioner according to an embodiment of the present invention;
FIG. 6 is a flow chart of a method for preventing refrigerant leakage of an air conditioner according to an embodiment of the present invention;
fig. 7 is a flowchart of a method of a refrigerant leakage verification procedure of an air conditioner according to an embodiment of the present invention.
Detailed Description
It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. In the embodiments of the present invention, the terms "first", "second", and the like are used for distinguishing identical items or similar items having substantially the same functions or actions, and those skilled in the art will understand that the terms "first", "second", and the like do not limit the quantity or execution order.
In order to make the technical solutions of the present invention better understood, the present invention will be further described in detail with reference to the accompanying drawings and specific embodiments.
In an embodiment of the present invention, an air conditioner includes a compressor, an indoor heat exchanger, and an outdoor heat exchanger.
Example 1
Fig. 1 is a flowchart of a refrigerant leakage detection method of an air conditioner according to an embodiment of the present invention, and as shown in fig. 1, the refrigerant leakage detection method of the air conditioner includes the following steps:
s1, judging whether the air conditioner operates normally according to the current load index of the air conditioner, if so, continuing normal operation of the air conditioner, and if not, acquiring the current operation mode of the air conditioner and executing a refrigerant judgment program;
specifically, the load index of the air conditioner comprises a compressor, a ventilation system and an electric control system of the air conditioner, the load of the ventilation system and the electric control system occupies a small proportion of the whole load of the air conditioner, and the influence of refrigerant leakage on the ventilation system and the electric control system is small, so that when the ventilation system and the electric control system operate well, the load of the air conditioner can be used for representing the load condition of the compressor. That is, when the judgment result shows that the air conditioner operates normally, it indicates that the refrigerant is not leaked; however, when the judgment result shows that the air conditioner is not operating normally, it indicates that refrigerant leakage may occur, or the load index of the air conditioner is abnormal due to a failure of the ventilation system or the electric control system, and it is necessary to further judge whether refrigerant leakage occurs.
Further, when the operation of the air conditioner is judged to be abnormal in step S1, the compressor is set to be in a shutdown state and restarted, so that the compressor stops working, and a stop reason code is sent to the control module or the display screen, so that the air conditioner starts a self-checking program of the ventilation system and the electric control system, and if the ventilation system and the electric control system operate well, the control module controls the compressor to restart automatically for further judgment.
And further, judging whether the compressor is in a non-working state, if not, acquiring the current running mode of the air conditioner by the acquisition module, and executing a refrigerant judgment program.
And S2, when the current operation mode of the air conditioner is a heating mode, judging whether the air conditioner has refrigerant leakage according to the outdoor environment temperature, the continuous operation time of the compressor and the opening degree of the expansion valve.
Specifically, when the running state of the compressor meets a first preset condition and the opening degree of the expansion valve is larger than a first set threshold value, the occurrence of refrigerant leakage is indicated, and at the moment, the control device sends a refrigerant leakage alarm signal to prompt a user to check and maintain in time, so that the situations that a motor in the compressor is overheated due to refrigerant leakage, the compressor is damaged, safety accidents are caused and the like are avoided.
Further, in this embodiment, the first preset condition is set according to an outdoor environment temperature, a continuous operation time of the compressor, and an opening degree of the expansion valve, the expansion valve is an electronic expansion valve, and is used as an automatic control energy-saving element to accurately control the opening degree of the expansion valve, and further, the opening degree of the expansion valve is continuously collected to effectively monitor whether a refrigerant leakage phenomenon exists.
S3, when the current operation mode of the air conditioner is a refrigeration mode or a dehumidification mode, tracking the circulation change from the refrigerant circulation process of the air conditioner, detecting the refrigerant leakage from the circulation change, and judging the current input power of the compressor along with the time when the refrigerant leaksRate of change (Δ W/Δ t)1And whether a second preset condition is met or not is judged, if yes, the outdoor unit is judged to have refrigerant leakage, and if not, the indoor unit is judged to have refrigerant leakage.
As shown in fig. 2, a refrigerant cycle process diagram L when the refrigerant quantity is normal is stored in the control system of the air conditioner0The refrigerant circulation process diagram L of the current air conditioner is that the circulation obtained when the refrigerant quantity is normal is different from the circulation obtained when the refrigerant leaks1Can track the change of the running state of the air conditioner in the whole refrigeration cycle, and when the leakage of the refrigerant is detected, the refrigerant cycle process diagram L in the current running state1The refrigerant circulation process diagram is L when the refrigerant quantity is not satisfied and the refrigerant quantity is normal0。
Further, the rate of change of the current input power through the compressor over time (Δ W/Δ t)1And judging whether the specific occurrence position of the refrigerant leakage is on a high-pressure side or a low-pressure side, if so, indicating that the refrigerant leakage occurs on the outdoor unit, and a maintenance worker only needs to disassemble and maintain the outdoor unit, and if so, indicating that the refrigerant leakage occurs on the indoor unit.
Further, the second preset condition is a time-dependent change rate (Δ W/Δ t) of the current input power1And the preset change rate threshold K is set according to the power of the compressor under the minimum load under the condition of normal refrigerant quantity.
The refrigerant leakage detection method provided by the embodiment can detect the air conditioners in different operation modes, can accurately judge whether the refrigerant leakage occurs on the indoor unit or the outdoor unit, is convenient for maintenance personnel to maintain in a targeted manner, and improves the maintenance efficiency. Moreover, the refrigerant leakage judging program provided by the embodiment has higher accuracy through multi-stage judgment, reduces the misjudgment rate, and avoids the situations that the motor in the compressor is overheated, the compressor is damaged, safety accidents are caused and the like due to refrigerant leakage.
Example 2
As shown in fig. 3 and 4, the present embodiment provides a method for detecting refrigerant leakage in a heating mode of an air conditioner, including the following steps:
s11, detecting the current load index of the air conditioner, wherein the current load index of the air conditioner is the current overall machine input current I of the air conditionera。
Specifically, if the air conditioner does not leak the refrigerant, the load index of the air conditioner is not changed greatly, and if the air conditioner leaks the refrigerant, so that the amount of the refrigerant in the compressor is reduced, the load of the compressor is reduced, and further the load index of the air conditioner is reduced.
The current input current of the whole air conditioner can be detected by current detection devices such as a current transformer and the like, the current transformer is not interfered by factors around a detection element, and the accuracy of the detected current value is high.
S12, judging the current input current I of the power transmission machineaWhether or not it is less than the first current threshold I1If so, the refrigerant leakage possibility is high, step S13 is executed, otherwise, the refrigerant is not leaked, and the air conditioner operates normally in the current state.
In particular, the first current threshold I1The input current value of the air conditioner is the whole machine input current value of the air conditioner under the minimum load when the refrigerant of the air conditioner is not leaked.
If IaIs less than I1If the compressor is started, the refrigerant leakage is detected, and the refrigerant leakage is possibly caused by unstable operation of the air conditioner or other faults, such as a ventilation system or a control system, which need to control the restart of the compressor for further judgment and detection; if IaNot less than I1If the refrigerant leakage does not occur, the air conditioner can keep normal operation.
S13, restarting the air conditioner, judging whether the compressor is in the running state, if so, executing a step S2; if not, the refrigerant determination program is not executed.
Specifically, the air conditioner is restarted to stop the compressor, a stop reason code is sent to the control module or the display screen, the air conditioner starts a self-checking program of the ventilation system and the electric control system, if the ventilation system and the electric control system operate well, the control module controls the compressor to automatically restart, the air conditioner performs further judgment in a specific operation mode, and if the compressor is in a non-working state all the time, the refrigerant judgment program is not executed.
S21, detecting outdoor environment temperature K in heating modeOuter coverAnd continuous compressor running time Ta；
Specifically, after the air conditioner is started, the air conditioner does not adjust the indoor environment temperature, the difference between the indoor environment temperature and the target temperature set by the user is large, the compressor runs at a high frequency after the air conditioner is started, the running state of the air conditioner tends to be stable after running for a period of time, and refrigerant leakage detection is started to prevent misjudgment from occurring when the running state of the air conditioner is not stable within a period of time after the air conditioner is started.
The outdoor environment temperature detector detects the outdoor environment temperature, the timing module is arranged in the air conditioner, and if the compressor starts to operate, the timing module sends a trigger signal to the timing module so as to realize the statistics of the operation time of the compressor by the timing module.
S22, judging whether the running state of the compressor reaches a first preset condition, if so, executing a step S23;
the first preset condition is; continuous running time T of compressoraIs longer than the first preset time T1And outdoor ambient temperature KOuter coverGreater than a set temperature K0. The first preset time T1Is selected and the outdoor ambient temperature KOuter coverIn this regard, the higher the outdoor ambient temperature, the smaller the first set time. When the outdoor environment temperature KOuter coverGreater than a set temperature K0And the continuous operation time T of the compressoraReaches the first preset time T1Then, carrying out the next judgment; if the compressor continues to operate for a time TaIs less than the first preset time T1Then, the operation is continued until TaReaches the first preset time T1。
And S23, when the running state of the compressor reaches a first preset condition, judging whether the opening degree of the expansion valve is larger than a first set threshold value, if so, judging that the refrigerant leaks, and if not, judging that the refrigerant does not leak.
The first set threshold is set according to the opening degree of the expansion valve under the condition that the refrigerant quantity is normal and the compressor operates at the highest frequency, and the opening degree of the expansion valve needs to be continuously detected so as to effectively monitor whether the refrigerant leakage phenomenon exists.
When the compressor is just started to operate, the difference between the indoor temperature and the target temperature set by the user is large, the compressor operates at a high frequency, the opening degree of the expansion valve is large for quickly adjusting the indoor temperature, and when the compressor operates continuously for a long time TaReaches the first preset time T1And then, the running state of the compressor tends to be stable, and the refrigerant leakage is detected through the opening degree of the expansion valve, so that the possibility of misjudgment is reduced.
Example 3
As shown in fig. 3 and 5 to 7, the present embodiment provides a method for detecting refrigerant leakage in a cooling mode of an air conditioner, including the following steps:
s11, detecting the current load index of the air conditioner, wherein the current load index of the air conditioner is the current overall machine input current I of the air conditionera。
Specifically, if the air conditioner does not leak the refrigerant, the load index of the air conditioner is not changed greatly, and if the air conditioner leaks the refrigerant, so that the amount of the refrigerant in the compressor is reduced, the load of the compressor is reduced, and further the load index of the air conditioner is reduced.
The current input current of the whole air conditioner can be detected by current detection devices such as a current transformer and the like, the current transformer is not interfered by factors around a detection element, and the accuracy of the detected current value is high.
S12, judging the input current I of the current input complete machineaWhether or not it is less than the first current threshold I1If yes, the refrigerant leakage possibility is high, and the step is executedIn step S13, if not, the refrigerant is not leaked, and the air conditioner operates normally in the current state.
In particular, the first current threshold I1When the refrigerant quantity of the air conditioner is equal to the standard refrigerant quantity, the whole machine input current value of the air conditioner under the minimum load is obtained.
If IaIs less than I1If the compressor is started, the refrigerant leakage is detected, and the refrigerant leakage is possibly caused by unstable operation of the air conditioner or other faults, such as a ventilation system or a control system, which need to control the restart of the compressor for further judgment and detection; if IaNot less than I1If the refrigerant leakage does not occur, the air conditioner can keep normal operation.
S13, restarting the air conditioner, judging whether the compressor is in the running state, if so, executing a step S2; if not, the refrigerant determination program is not executed.
And further, restarting to stop the compressor, sending a stop reason code to the control module or the display screen to start a self-checking program of the ventilation system and the electric control system of the air conditioner, if the ventilation system and the electric control system operate well, controlling the compressor to restart automatically by the control module, performing further judgment in a specific operation mode of the air conditioner, and if the compressor is always in a non-working state, not executing a refrigerant judgment program.
S31, judging the continuous operation time T of the compressor in the refrigeration mode or the dehumidification modebWhether the second preset time T is reached2If yes, executing step S32, otherwise, continuing normal operation of the compressor until reaching the second preset time T2。
The second preset time T2According to the outdoor ambient temperature KOuter coverAnd the lower the outdoor environment temperature is, the smaller the first set time is. When running time T continuouslybReaching the second preset time T2In time, the running state of the air conditioner tends to be stable, so that each running variable in the air conditioner can be conveniently measured, the accuracy of measuring the running variable is ensured, and the misjudgment rate is further reduced.
S32, determining the air conditionerObtaining the operation variable in the previous operation state to obtain the refrigerant circulation process diagram L in the current operation state1。
The operating variables include at least one of an indoor inlet pipe temperature, a suction temperature, a liquid pipe temperature, a compressor discharge pressure, a compressor suction pressure, and an outdoor heat exchanger outlet temperature. Measuring the operation variables of the air conditioner in real time under the current operation state to obtain a refrigerant circulation process diagram L under the state1。
Firstly, when the quantity of refrigerant is normal, the operation variable of the air conditioner in the normal operation state is monitored in real time, and a refrigerant circulation process diagram L in the state is obtained0And stored in the storage system of the air conditioner.
S33, judging refrigerant circulation process diagram L under current operation state1And whether the refrigerant circulation process diagram L in the normal state is satisfied0If yes, step S34 is executed, and if no, step S35 is executed.
As shown in fig. 2, the cycle process obtained when the refrigerant quantity is normal and the cycle process obtained when the refrigerant quantity is reduced due to refrigerant leakage are different, and there are many factors affecting the refrigerant cycle process, and the refrigerant cycle process diagram is L in the case where all the operation variables including the refrigerant quantity are normal0(ii) a Any variable change, including refrigerant leakage, can cause the refrigerant circulation process in the current operation state to change, and a refrigerant circulation process diagram L in the current operation state is judged1The refrigerant circulation process chart is L under the condition of whether the normal condition is met0If not, the refrigerant has a high possibility of leakage, and step S35 is executed to further determine whether the refrigerant leaks; if yes, it is determined that the refrigerant is not leaked, and step S34 is executed.
Specifically, as shown in fig. 2, the refrigerant circulation process includes: a compression process a, a condensation process b, a throttling process c and an evaporation process d; can be compared by the maximum pressure in the refrigerant circulation process or the enthalpy change in the compression process, and the maximum pressure P of the refrigerant under the current operation state1Less than the maximum pressure P of the refrigerant in the normal state0In time, it is judged that the refrigerant is likely to leakThe sex is relatively large. Preferably, the determination may be made by other variables in the cycle, such as enthalpy change, compression suction pressure, etc., and the present invention is not limited thereto.
And S34, starting a refrigerant leakage prevention program.
The compressor is carrying out high-temperature high-pressure compression in-process to the refrigerant, because the influence of factors such as reciprocating compression removal, refrigerant pressure variation of compression part can make compressor self produce great vibration, and the vibration can transmit to the refrigerant pipeline that is connected with the compressor on, leads to the refrigerant pipeline also can the vibration to appear, and especially when the refrigerant pipeline vibrates on the resonance point, very easily lead to the solder joint on the refrigerant pipeline to shake and split, arouses the problem that the refrigerant leaked. Therefore, the working frequency of the compressor is controlled to avoid the resonance point of the refrigerant pipeline, so that the effect of preventing the welding point of the refrigerant pipeline from being broken is achieved.
And S341, detecting the vibration frequency of the refrigerant pipeline.
Further, the vibration frequency is obtained by measuring the amplitude and the strain of the refrigerant pipeline. Specifically, the sensor detects vibration data of the pipeline and the compressor during vibration, such as physical quantities of vibration displacement, speed, acceleration, frequency, phase and the like, and then converts the physical quantities into electric signals, and then the electric signals are transmitted to a computer board of the air conditioner, the computer board analyzes the amplitude quantity and the strain quantity of the refrigerant pipeline having a vibration transmission relation with the compressor, and the vibration frequency is further calculated.
S342, judging whether the vibration frequency of the refrigerant pipeline is within the resonance frequency range of the compressor, if so, indicating that the compressor and the refrigerant pipeline have resonance phenomena, the risk of vibration cracking of the refrigerant pipeline is high, and the compressor needs to execute frequency conversion operation and adjust the operating frequency of the compressor so as to enable the vibration frequency of the refrigerant pipeline to avoid the resonance frequency range which is easy to cause vibration cracking of welding points; if not, the vibration frequency of the refrigerant pipeline is in a reasonable frequency range, the resonance phenomenon cannot occur, the risk that the welding spot of the refrigerant pipeline is cracked by vibration is low, the compressor can run continuously at the frequency temporarily, and the judgment process is ended.
S35, judgmentDischarge temperature T of compressordTemperature T of inlet air of outdoor heat exchangercIf the third preset condition is met, if yes, step S36 is executed to enter the refrigerant leakage verification procedure, and if not, the compressor is controlled to continue to operate.
The third preset condition is Td＞A+B*TcA, B is a preset constant, it should be noted that, at different outdoor temperatures, the discharge temperature T of the compressor is related to the refrigerant leakage in the air conditionerdHas obvious change and the inlet air temperature T of the outdoor heat exchangercAnd the linear corresponding relation is formed.
When T isd＞A+B*TcIf the refrigerant leakage is determined to occur, step S36 is executed to enter a refrigerant leakage verification procedure, and the specific position where the leakage occurs is determined; when T isd≦A+B*TcAnd judging that the refrigerant is not leaked, and controlling the compressor to continuously operate in the state.
The step S36 includes:
s361, detecting the time-varying rate (delta W/delta t) of the input power of the compressor1。
Wherein, in the refrigeration mode, the refrigerant of the indoor machine is in a low pressure state, the refrigerant of the outdoor machine is in a high pressure state, when the refrigerant leaks in the indoor machine, the refrigerant pipeline can rapidly suck air, so that the load of the compressor is suddenly increased, and the change rate (delta W/delta t) of the input power of the compressor along with the time is increased1Is large; when the outdoor unit leaks refrigerant, the refrigerant amount in the refrigerant pipeline is reduced, and air is not easy to enter the refrigerant pipeline, so that the change rate (delta W/delta t) of the input power of the compressor along with time is ensured1Is smaller.
S362, judging the time-dependent change rate (delta W/delta t) of the current input power of the compressor1And if the change rate is larger than the preset change rate threshold K, judging that the refrigerant leaks from the low-pressure side, and if not, judging that the refrigerant leaks from the high-pressure side. And the change rate threshold K is set according to the change rate of the input power of the compressor along with the time when the refrigerant is not leaked. When (Δ W/Δ t)1If the K is larger than the K, the indoor unit is indicated to have refrigerant leakage; when (Δ W/Δ t)1When K is less than K, the chamber is describedThe outdoor unit generates refrigerant leakage.
This embodiment can accurate judgement whether refrigerant leaks to can judge whether refrigerant leaks and take place on indoor set or off-premises station, the after-sales maintenance of being convenient for reduces maintenance workman's pressure.
Example 4
This embodiment provides an air conditioner refrigerant leakage detection system, the air conditioner includes compressor, indoor heat exchanger and outdoor heat exchanger, detection system includes:
and the acquisition module is used for acquiring the complete machine input current and the operation mode of the air conditioner and the operation time and the input power of the compressor.
And the control module is used for controlling the on-off and the running state of the compressor and controlling and starting a leakage-proof program of the refrigerant pipeline.
And the detection module is used for detecting the temperature of an indoor inlet pipe of the air conditioner, the exhaust temperature of the compressor, the outdoor environment temperature, the air inlet temperature of the outdoor heat exchanger and the vibration frequency of the refrigerant pipeline and the compressor.
Specifically, the indoor inlet pipe temperature sensor measures the temperature of the refrigerant entering the indoor heat exchanger. The indoor inlet pipe temperature sensor is provided on a connection pipe connecting the indoor heat exchanger and the indoor expansion valve.
The suction temperature sensor measures a temperature of a refrigerant sucked into the compressor. The suction temperature sensor is provided on a suction pipe of the compressor. The control unit determines whether the suction temperature is normal in the normal operation state through the suction temperature sensor.
The liquid pipe temperature sensor measures a temperature of the refrigerant flowing between the subcooler and the indoor heat exchanger. The liquid pipe temperature sensor is arranged on a liquid pipe connecting the subcooler and the indoor unit. The control module determines whether the temperature of the liquid pipe is normal under the normal operation state through the liquid pipe temperature sensor.
The outdoor heat exchanger outlet temperature sensor measures a temperature of a refrigerant condensed in the outdoor heat exchanger during a cooling operation or measures a temperature of a refrigerant evaporated in the outdoor heat exchanger during a heating operation.
The high pressure sensor measures the pressure of the refrigerant discharged from the compressor. The high pressure sensor is disposed on the discharge pipe of the compressor. The control unit determines whether the discharge superheat degree has a normal value in a normal operation state through the high pressure sensor by calculating a saturation temperature of the discharged refrigerant and calculating a difference between the saturation temperature and a discharge temperature measured by the discharge temperature sensor.
The low pressure sensor measures the pressure of the refrigerant sucked into the compressor. The low pressure sensor is disposed on a suction pipe of the compressor. The control unit determines whether the suction superheat degree is normal in a normal operation state through the low pressure sensor by calculating a saturation temperature of the sucked refrigerant and calculating a difference between the saturation temperature and a suction temperature measured by the suction temperature sensor.
The refrigerant leakage detection system of the air conditioner provided by the embodiment can reduce the misjudgment and the leakage judgment rate of the refrigerant leakage by adopting the refrigerant leakage detection method in the embodiments 1 to 3, is convenient for maintenance personnel to maintain in a targeted manner, and improves the maintenance efficiency.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (6)

1. A method for detecting the refrigerant leakage of an air conditioner is characterized by comprising the following steps:
s1, judging whether the air conditioner operates normally according to the current load index of the air conditioner, if so, continuing normal operation of the air conditioner, and if not, acquiring the current operation mode of the air conditioner and executing a refrigerant judgment program;
the S1 includes the following steps: s11, detecting the current load index of the air conditioner, wherein the load index of the air conditioner is the current overall machine input current I of the air conditionera；
S12, judging the current input current I of the whole machineaWhether or not it is less than the first current threshold I1If so, the refrigerant leakage possibility is high, step S13 is executed, otherwiseNamely, the refrigerant is not leaked, and the air conditioner normally operates in the current state;
s13, restarting the air conditioner, judging whether the compressor is in the running state, if so, executing a step S2; if not, the refrigerant judgment program is not executed; restarting to stop the compressor, sending a stop reason code to the control module or the display screen to start a self-checking program of the ventilation system and the electric control system of the air conditioner, if the ventilation system and the electric control system run well, controlling the compressor to automatically restart by the control module, performing further judgment in a specific running mode of the air conditioner, and if the compressor is always in a non-working state, not executing a refrigerant judgment program;
s2, when the current operation mode of the air conditioner is a heating mode, judging whether the air conditioner has refrigerant leakage according to the outdoor environment temperature, the continuous operation time of the compressor and the opening degree of the expansion valve;
s3, when the current operation mode of the air conditioner is a refrigeration mode or a dehumidification mode, tracking the circulation change from the refrigerant circulation process of the air conditioner, detecting the refrigerant leakage from the circulation change, and judging the time-dependent change rate (delta W/delta t) of the current input power of the compressor when the refrigerant leaks1Whether a second preset condition is met or not is judged, if yes, the indoor unit is judged to have refrigerant leakage, and if not, the outdoor unit is judged to have refrigerant leakage;
the S3 includes the following steps:
s31, judging the continuous operation time T of the compressorbWhether the second preset time T is reached2If yes, executing step S32, otherwise, continuing normal operation of the compressor until reaching the second preset time T2；
S32, measuring the operation variables of the air conditioner in the current operation state to obtain a refrigerant circulation process diagram L in the current operation state1；
S33, judging refrigerant circulation process diagram L under current operation state1And whether the refrigerant circulation process diagram L in the normal state is satisfied0If yes, go to step S34, otherwise go to step S35;
s34, starting a refrigerant leakage prevention program;
the refrigerant leakage prevention detection program comprises the following steps:
s341, detecting the vibration frequency of the refrigerant pipeline;
s342, judging whether the vibration frequency of the refrigerant pipeline is in the resonance frequency range of the compressor, if so, adjusting the running frequency of the compressor, and if not, ending the process;
s35, judging whether a third preset condition is met between the exhaust temperature Td of the compressor and the inlet air temperature Tc of the outdoor heat exchanger, if so, executing a step S36 to enter a refrigerant leakage verification program, and if not, controlling the compressor to continue to operate;
the third preset condition is Td＞A+B*TcAnd A, B is a predetermined constant.
2. The method for detecting refrigerant leakage of an air conditioner as claimed in claim 1, wherein said S36 includes steps of:
s361, detecting the time-varying rate (delta W/delta t) of the input power of the compressor1；
S362, judging the time-dependent change rate (delta W/delta t) of the current input power of the compressor1And if the change rate is larger than the preset change rate threshold K, judging that the indoor unit has refrigerant leakage, and if not, judging that the outdoor unit has refrigerant leakage.
3. An air conditioner refrigerant leakage detecting method as claimed in claim 1, wherein said operation variables include at least one of an indoor inlet pipe temperature, a suction temperature, a liquid pipe temperature, a compressor discharge pressure, a compressor suction pressure, and an outdoor heat exchanger outlet temperature.
4. The method as claimed in claim 2, wherein the first current threshold I is set to be greater than a first threshold value1When the refrigerant quantity of the air conditioner is equal to the standard refrigerant quantity, the current is input into the compressor under the minimum load.
5. An air conditioner refrigerant leakage detection system capable of performing the air conditioner refrigerant leakage detection method according to any one of claims 1 to 4, the air conditioner including a compressor, an indoor heat exchanger, and an outdoor heat exchanger, the detection system comprising:
the acquisition module is used for acquiring the complete machine input current and the operation mode of the air conditioner and the operation time and the input power of the compressor;
the control module is used for controlling the on-off and the running state of the compressor and controlling and starting a leakage-proof program of the refrigerant pipeline;
and the detection module is used for detecting the temperature of an indoor inlet pipe of the air conditioner, the exhaust temperature of the compressor, the outdoor environment temperature, the air inlet temperature of the outdoor heat exchanger and the vibration frequency of the refrigerant pipeline and the compressor.
6. The system of claim 5, wherein the detection module comprises a temperature sensor and a pressure sensor, the temperature sensor is respectively disposed on a connection pipe of the indoor heat exchanger and the indoor expansion valve, a suction pipe of the compressor, a connection pipe of the subcooler and the indoor unit, and an outlet of the outdoor heat exchanger, and the pressure sensor is respectively disposed on a discharge pipe and a suction pipe of the compressor.
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1764812A (en) * 2003-09-19 2006-04-26 株式会社东芝 Refrigerant leakage detecting device and refrigerator using the same
CN102147142A (en) * 2010-02-08 2011-08-10 Lg电子株式会社 Air conditioner and method for controlling air conditioner
CN107314519A (en) * 2017-06-14 2017-11-03 海信科龙电器股份有限公司 A kind of decision method and device of air-conditioner coolant leakage
CN107576112A (en) * 2017-09-19 2018-01-12 青岛海尔空调器有限总公司 Detection method and device, air-conditioning for refrigerant leakage

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1764812A (en) * 2003-09-19 2006-04-26 株式会社东芝 Refrigerant leakage detecting device and refrigerator using the same
CN102147142A (en) * 2010-02-08 2011-08-10 Lg电子株式会社 Air conditioner and method for controlling air conditioner
CN107314519A (en) * 2017-06-14 2017-11-03 海信科龙电器股份有限公司 A kind of decision method and device of air-conditioner coolant leakage
CN107576112A (en) * 2017-09-19 2018-01-12 青岛海尔空调器有限总公司 Detection method and device, air-conditioning for refrigerant leakage

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