CN113883703A - Air conditioner indoor unit - Google Patents

Air conditioner indoor unit Download PDF

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Publication number
CN113883703A
CN113883703A CN202111234220.7A CN202111234220A CN113883703A CN 113883703 A CN113883703 A CN 113883703A CN 202111234220 A CN202111234220 A CN 202111234220A CN 113883703 A CN113883703 A CN 113883703A
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China
Prior art keywords
voltage
controller
direct current
current
power
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Granted
Application number
CN202111234220.7A
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Chinese (zh)
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CN113883703B (en
Inventor
张俊喜
任兆亭
李希志
王静
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Qingdao Hisense Hitachi Air Conditioning System Co Ltd
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Qingdao Hisense Hitachi Air Conditioning System Co Ltd
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Priority to CN202111234220.7A priority Critical patent/CN113883703B/en
Publication of CN113883703A publication Critical patent/CN113883703A/en
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Publication of CN113883703B publication Critical patent/CN113883703B/en
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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
    • F24F11/88—Electrical aspects, e.g. 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
    • F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
    • F24F11/49—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring ensuring correct operation, e.g. by trial operation or configuration checks
    • 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
    • F24F11/72—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure
    • F24F11/74—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity
    • F24F11/77—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity by controlling the speed of ventilators
    • 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
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
    • Y02B30/70—Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Thermal Sciences (AREA)
  • Air Conditioning Control Device (AREA)

Abstract

The invention discloses an air-conditioning indoor unit, which comprises a high-voltage direct-current circuit, a low-voltage direct-current circuit, an electric signal detection circuit, a direct-current fan, an electronic expansion valve and a controller, wherein the high-voltage direct-current circuit is connected with the low-voltage direct-current circuit; the high-voltage direct current circuit is respectively connected with the low-voltage direct current circuit, the electric signal detection circuit and the direct current fan; the controller is respectively connected with the direct current fan, the low-voltage direct current circuit and the electronic expansion valve and respectively controls the power supply and the operation of the direct current fan and the electronic expansion valve; the electric signal detection circuit detects a voltage signal or a current signal and transmits the voltage signal or the current signal to the controller; the controller judges whether the power is cut off or not, and controls the direct current fan to stop running and the electronic expansion valve to be closed when the power is cut off. The invention controls the direct current fan to stop running when power is off, the electric quantity stored by the high-voltage direct current circuit supplies power to the controller and the electronic expansion valve, the electronic expansion valve is controlled to be closed, refrigerant circulation is cut off, and condensation around the evaporator and liquid impact of the compressor are prevented.

Description

Air conditioner indoor unit
Technical Field
The invention relates to the technical field of air conditioning, in particular to an air conditioner indoor unit.
Background
When the indoor unit of the air conditioner is powered off, the coil of the electronic expansion valve is powered off at the same time, the valve body cannot be driven to close, and the opening degree of the valve is kept in a state before power failure. After the power failure, the refrigerant continues to flow in the evaporator of the indoor unit under the action of the pressure difference between the indoor unit and the outdoor unit of the air conditioner. Because the fan of air conditioner indoor set falls the unable operation of power failure simultaneously, makes the evaporimeter temperature of indoor set reduce rapidly, leads to the steam condensation in the air around the evaporimeter to form the water droplet and drip outside the indoor set, influences user's use and experiences. In addition, since the outdoor unit is still in operation and the refrigerant in the evaporator of the indoor unit is still in a liquid state, it returns to the compressor during the refrigeration cycle, causing liquid slugging of the compressor and damage to the compressor.
At present, a backup power supply, a battery, or an Uninterruptible Power Supply (UPS) is additionally added to the indoor unit to supply power to the indoor unit after power failure, so as to control the closing of the electronic expansion valve. The above-mentioned backup power supply, battery or Uninterruptible Power Supply (UPS), etc. have no other uses when the indoor unit is operating normally, increasing the cost of the indoor unit of the air conditioner.
Disclosure of Invention
In order to solve the problems of poor user experience, compressor damage or increased cost of the indoor unit of the air conditioner caused by power failure of the indoor unit in the prior art, the invention provides the indoor unit of the air conditioner, which solves the problems of condensation around an evaporator and compressor damage in the power failure process on the premise of not increasing hardware, improves the user experience and reduces the cost.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention provides an air-conditioning indoor unit, which comprises a high-voltage direct-current circuit, a low-voltage direct-current circuit, an electric signal detection circuit, a direct-current fan, an electronic expansion valve, a controller and at least one low-voltage load, wherein the high-voltage direct-current circuit is connected with the low-voltage direct-current circuit;
the high-voltage direct current circuit is respectively connected with the low-voltage direct current circuit, the electric signal detection circuit and the direct current fan; the controller is respectively connected with the direct current fan, the low-voltage direct current circuit, the electronic expansion valve and the low-voltage load and respectively controls the power supply and the operation of the direct current fan, the electronic expansion valve and the low-voltage load;
the electric signal detection circuit detects a voltage signal or a current signal and transmits the voltage signal or the current signal to the controller; the controller judges whether to cut off the power supply according to the received voltage signal or the current signal; and when the controller judges that the power is off, the direct current fan and the low-voltage load are controlled to stop running, and the electronic expansion valve is controlled to be closed.
In one embodiment, the electrical signal detection circuit includes a dc voltage detection circuit, which detects the voltage of the high voltage dc circuit, records the voltage as a dc voltage, and transmits the dc voltage to the controller;
the controller is configured with a power-down slope limit value and normal voltage; the controller calculates a power-down slope according to the direct-current voltage, and compares the power-down slope with a power-down slope limit value and the direct-current voltage with the normal voltage;
and when the power failure slope is larger than the power failure slope limit value and the direct current voltage is smaller than the normal voltage, controlling the direct current fan to operate in a frequency reduction mode.
In one embodiment, when the dc fan operates in a down-conversion mode, the down-conversion rate is positively correlated to the power-down slope.
In one embodiment, the controller is configured with an under-voltage limit, and determines whether to power off according to the direct current voltage and the under-voltage limit;
when the direct current voltage is smaller than the under-voltage limit value, the controller judges that the power is cut off, controls the direct current fan and the low-voltage load to stop running, and controls the electronic expansion valve to be closed.
In one embodiment, the electric signal detection circuit further comprises an alternating current detection circuit, which is connected with the controller and the high voltage direct current circuit and is used for detecting an electric signal of the power supply alternating current connected with the high voltage direct current circuit;
the alternating current detection circuit sends the electric signal to the controller; the controller judges whether the power is off or not according to the electric signal;
and when the controller judges that the power is off, the direct current fan and the low-voltage load are controlled to stop running, and the electronic expansion valve is controlled to be closed.
In some embodiments, the outdoor unit further comprises a communication module connected with the controller and used for being in communication connection with the outdoor unit;
when the controller judges that the power is off, the communication module is controlled to send a power-off signal for the outdoor unit to control the compressor to stop running;
and the controller controls the communication module to stop working after the power-off signal is sent.
In some embodiments, further comprising a power-down memory coupled to the controller;
when the controller judges that the power is cut off, the power failure memory is controlled to store the set states of the direct current fan, the electronic expansion valve and the low-voltage load before the power is cut off;
when the electric signal or the direct current voltage returns to normal in a short time and keeps for a specified time, the controller controls the direct current fan, the electronic expansion valve and the low-voltage load to return to the set state before power failure.
In some embodiments, the system further comprises frequency converters respectively connected with the high-voltage direct-current circuit, the direct-current fan and the controller;
the controller controls the connection or disconnection of each path of the frequency converter, and changes the connection state of the high-voltage direct-current circuit and the direct-current fan;
and when the controller judges that the power is off, the controller controls the connection or disconnection of each path of the frequency converter to stop the direct current fan, and the back electromotive force of the direct current fan charges the high-voltage direct current circuit.
In some embodiments, a current detection circuit is further included; the high-voltage direct current circuit comprises a direct current bus electrolytic capacitor which is connected with the frequency converter;
the current detection circuit is respectively connected with the controller, the frequency converter and the direct-current bus electrolytic capacitor, and is used for detecting the current between the frequency converter and the direct-current bus electrolytic capacitor and transmitting the current to the controller;
the controller is configured with a voltage preset value and a current preset value; when the direct current fan stops running, the controller controls the duty ratio of the passage of the frequency converter according to the rotating speed of the direct current fan, so that the voltage of the electrolytic capacitor of the direct current bus does not exceed the preset voltage value, and the charging current does not exceed the preset current value.
In some embodiments, the controller is configured with a current low threshold and compares the current between the frequency converter and the dc bus electrolytic capacitor to the current low threshold;
when the voltage of the direct current bus electrolytic capacitor is not increased any more or the current supplied to the direct current bus electrolytic capacitor by the counter electromotive force is smaller than the current low threshold value, the controller controls the passage of the frequency converter to be closed.
Compared with the prior art, the technical scheme of the invention has the following technical effects:
according to the air conditioner indoor unit, when the power failure is judged, the direct current fan and the low-voltage load are controlled to stop running, so that the electric quantity stored by the high-voltage direct current circuit is only supplied to the controller and the electronic expansion valve, and the controller controls the electronic expansion valve to be closed, the power failure is detected and the electronic expansion valve is controlled to be closed under the condition that no additional circuit or power supply is added to the air conditioner indoor unit, the circulation of a refrigerant is cut off, the condensation around the evaporator and the liquid impact of the compressor caused by rapid temperature reduction of the evaporator and low temperature maintenance are prevented, the user experience is improved, the compressor is protected, and the service life of the compressor is prolonged; in addition, no extra circuit and/or power supply is added, the service life of the compressor is prolonged, resources are saved, and the cost is reduced.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
Fig. 1 is a schematic circuit diagram of an embodiment of an indoor unit of an air conditioner according to the present invention;
fig. 2 is a schematic diagram of the power-down of the dc voltage of an embodiment of an indoor unit of an air conditioner according to the present invention;
FIG. 3 is a schematic diagram of a control timing sequence of an indoor unit of an air conditioner according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of a control timing sequence of an indoor unit of an air conditioner according to an embodiment of the present invention;
fig. 5 is a control flowchart of an embodiment of an indoor unit of an air conditioner according to the present invention;
FIG. 6 is a schematic circuit diagram of an embodiment of an indoor unit of an air conditioner according to the present invention;
FIG. 7 is a schematic diagram of a control timing sequence of an indoor unit of an air conditioner according to an embodiment of the present invention;
fig. 8 is a control flowchart of an embodiment of an indoor unit of an air conditioner according to the present invention;
fig. 9 is a schematic circuit diagram of an embodiment of an indoor unit of an air conditioner according to the present invention;
fig. 10 is a schematic diagram of back emf charging the dc bus electrolytic capacitor.
Reference numerals:
1. a high voltage direct current circuit; 2. a low voltage DC circuit; 31. a direct current voltage detection circuit; 32. an alternating current detection circuit; 4. a direct current fan; 5. a controller; 6. a low voltage load; 7. an electronic expansion valve; 8. a communication module; 9. a frequency converter; 10. a frequency converter drive circuit; 20. an electronic expansion valve drive circuit; 30. a current detection circuit; 40. a power down memory;
c1, a direct current bus electrolytic capacitor; DM1, a rectification circuit; vdcAnd a direct current voltage.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it should be noted that the terms "mounted," "connected," and "connected" are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected unless otherwise explicitly stated or limited. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art. In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.
Referring to fig. 1, 3, 4, 5, 6, 7, 8 and 9, the indoor unit of an air conditioner according to the present invention includes a high voltage dc circuit 1, a low voltage dc circuit 2, an electric signal detection circuit, a dc fan 4, an electronic expansion valve 7, a controller 5, and at least one low voltage load 6.
The high-voltage direct-current circuit 1 is connected with power supply alternating current, converts the alternating current into stable high-voltage direct current and outputs the stable high-voltage direct current, and comprises an energy storage element for filtering. The high-voltage direct-current circuit 1 is respectively connected with the low-voltage direct-current circuit 2, the electric signal detection circuit and the direct-current fan 4; the controller 5 is respectively connected with the electric signal detection circuit, the direct current fan 4, the low-voltage direct current circuit 2, the electronic expansion valve 7 and the low-voltage load 6, and respectively controls the power supply and the operation of the direct current fan 4, the electronic expansion valve 7 and the low-voltage load 6.
The electric signal detection circuit detects a voltage signal or a current signal and transmits the voltage signal or the current signal to the controller 5; the controller 5 judges whether to cut off the power supply according to the received voltage signal or current signal; and when the controller 5 judges that the power is off, the direct current fan 4 and the low-voltage load 6 are controlled to stop supplying power and running, and the electronic expansion valve 7 is controlled to be closed.
The air-conditioning indoor unit detects a voltage signal or a current signal of a circuit through an electric signal detection circuit and judges whether to cut off the power supply or not through a controller 5 according to the voltage signal or the current signal; can be detected during the power-off process. When the controller 5 judges that the power is cut off and the actual power is not completely cut off, the high-power-consumption direct current fan 4 is controlled to stop running, and the low-voltage load 6 can be simultaneously or subsequently controlled to stop running, so that the electric energy stored in the high-voltage direct current circuit 1 only supplies power for the controller 5 and the electronic expansion valve 7; when the controller 5 controls the electronic expansion valve 7 to be closed, the electronic expansion valve 7 can be completely closed.
When the indoor unit of the air conditioner is powered off, the electronic expansion valve 7 can be closed, so that the refrigerant in the running outdoor unit stops circulating into the evaporator of the indoor unit, the evaporator of the indoor unit is prevented from being condensed around due to rapid cooling caused by the stop of the direct current fan 4, and the user experience is improved; in addition, the electronic expansion valve 7 is closed, the circulation of the refrigerant of the indoor unit and the outdoor unit is cut off, the liquid refrigerant which passes through the evaporator and is not evaporated returns to the compressor, the liquid impact of the compressor is avoided, the compressor is protected, and the service life of the compressor is prolonged.
According to the invention, because the service life of the compressor is prolonged, and the power-off electronic expansion valve 7 is closed without adding an additional detection circuit and power supply equipment, the user experience is improved and the maintenance cost is reduced on the premise of not increasing the cost of the indoor unit of the air conditioner.
In some embodiments, referring to fig. 1, 6 and 9, the hvdc circuit 1 includes a rectifying circuit DM1, a dc bus electrolytic capacitor C1; the rectifier circuit DM1 is connected to the supply ac power and rectifies the supply ac power. The direct current bus electrolytic capacitor C1 is connected with the rectifying circuit DM1, and the voltage and the current output by the rectifying circuit DM1 are filtered, so that the ripple waves are reduced, and the stable high-voltage direct current is output.
The direct current bus electrolytic capacitor C1 is a large-capacity capacitor and has certain power storage capacity.
In some embodiments, referring to fig. 1, 6 and 9, the low voltage dc circuit 2 is a switching power supply circuit, which is connected to the high voltage dc circuit 1 to generate and output low voltage voltages of 5V, 12V and 15V for supplying power to the controller 5 and supplying power to the low voltage load 6 and the electronic expansion valve 7.
In some embodiments, referring to fig. 1, fig. 2, fig. 3, fig. 4, fig. 5, fig. 6 and fig. 9, the electrical signal detection circuit includes a dc voltage detection circuit 31 connected to the high voltage dc circuit 1 for detecting a dc bus voltage denoted as dc voltage Vdc。
The dc voltage detection circuit 31 is connected to the controller 5, and detects the dc voltage VdcTo the controller 5. The controller 5 is configured with a power down slope limit, normal voltage. The controller 5 receives the DC voltage VdcCalculating the power-down slope, comparing the power-down slope with the power-down slope limit value and the DC voltage VdcAnd a normal voltage; when the power-off slope is larger than the power-off slope limit value and the direct-current voltage VdcAnd when the voltage is lower than the normal voltage, controlling the direct current fan 4 to perform frequency reduction operation.
This embodiment is at DC voltage VdcAnd when the abnormality occurs, the direct current fan 4 is controlled to operate in a frequency reduction mode, the energy consumption of the direct current fan 4 is reduced, and preparation is made for controlling the direct current fan 4 to stop operating.
In some embodiments, referring to fig. 3 and 4, the controller 5 controls the dc fan 4 to perform the down-conversion operation at a down-conversion rate and a dc voltage VdcIs proportional or positively correlated.
In some embodiments, referring to fig. 1, 3 and 4, the controller 5 is configured with an under-voltage limit and configured to compare the received dc voltage VdcAnd an under voltage limit.
When the DC voltage V isdcWhen the voltage is less than the under-voltage limit value, the controller 5 judges that the power is off, and controls the direct current fan 4 and the low-voltage load 6 to stop running and controls the electronic expansion valve 7 to close.
In an embodiment, referring to fig. 6, 7 and 8, the electrical signal detection circuit includes an ac detection circuit 32 connected to the controller 5 and the hvdc circuit 1 for detecting the electrical signal of the supply alternating current connected to the hvdc circuit 1.
The alternating current detection circuit 32 transmits the detected electric signal to the controller 5; the controller 5 determines whether to power off according to the received electric signal.
And when the power is cut off, controlling the direct current fan 4 and the low-voltage load 6 to stop running and controlling the electronic expansion valve 7 to close.
The air-conditioning indoor unit of the embodiment detects the power supply condition of the power supply alternating current through the alternating current detection circuit 32; when the power supply alternating current is abnormal, the controller 5 judges the power failure through the abnormality of the electric signal, further controls the direct current fan 4 and the low-voltage load 6 to stop running, controls the electronic expansion valve 7 to be closed, shortens the judgment time, improves the control efficiency, and improves the reliability of closing control of the electronic expansion valve 7.
In one embodiment, the ac detection circuit may be a zero crossing detection circuit or an ac voltage detection circuit.
In some embodiments, referring to fig. 1, 6 and 9, the indoor unit of the air conditioner further includes a communication module 8 connected to the controller 5 for communicating with the outdoor unit.
When the controller 5 judges that the power is cut off, firstly, the direct current fan 4 is controlled to stop running, and the low-voltage load 6 is controlled to stop running; then controlling the communication module 8 to send a power-off signal; and when the outdoor unit receives a power-off signal, controlling the compressor to stop running.
After the controller 5 finishes sending the power-off signal, the controller controls the communication module 8 to stop working, and then controls the electronic expansion valve 7 to close.
The indoor unit of the air conditioner of the embodiment sends a power-off signal to the outdoor unit when the power is off, so as to control the outdoor compressor to stop running, reduce the pressure of the refrigerant before the electronic expansion valve 7 is closed, and prevent the electronic expansion valve 7 and the refrigerant pipeline from being damaged.
In an embodiment, referring to fig. 1, 6 and 9, the indoor unit of the air conditioner further includes a communication module 8; when the controller 5 judges that the power is cut off, the communication module 8 is controlled to send a power-off signal; and when the outdoor unit receives a power-off signal, controlling the compressor to stop running.
And after the controller 5 finishes sending the power-off signal, the direct current fan 4 is controlled to stop running, the low-voltage load 6 is controlled to stop running, and then the electronic expansion valve 7 is controlled to be closed.
The air-conditioning indoor unit of the embodiment first controls the compressor to stop running, controls the pressure and circulation of the refrigerant in the system, then controls the direct current fan 4 and the low-pressure load 6 to stop running, and finally controls the electronic expansion valve 7 to close. Firstly, the compressor is controlled to stop running, the circulation speed of a refrigerant is slowed down, and the problem of rapid temperature reduction of an indoor evaporator caused by the stop running of the direct current fan 4 during power failure is solved; and the problem of condensation of the indoor evaporator and liquid impact of the compressor is further solved by closing the electronic expansion valve 7, so that the user experience is improved, the service life of the compressor is prolonged, and the cost is saved.
In some embodiments, the low voltage load 6, with reference to fig. 1, 6 and 9, may be one or any number of relays, inputs, displays, line controllers, network communication devices, and the like.
In some embodiments, referring to fig. 6, 7, 8 and 9, the indoor unit of the air conditioner further includes a power down memory 40, which is connected to the controller 5 and is used for saving the operation settings of the indoor unit of the air conditioner, which may include the setting states of the dc fan 4, the low-voltage load 6 and the electronic expansion valve 7 before power failure, when the controller 5 determines that power failure occurs.
When an electric signal or a DC voltage VdcAnd when the normal state is recovered in a short time and the indoor unit of the air conditioner is kept for a set time, the controller 5 controls the direct current fan 4, the low-voltage load 6 and the electronic expansion valve 7 to gradually recover to the running state before power failure according to the running setting of the indoor unit of the air conditioner stored in the power failure memory 40.
The air conditioner indoor unit of this embodiment can resume the running state before the outage by oneself when the short-term outage, need not user's manual recovery, promotes user experience.
In one embodiment, power-down memory 40 is an EEPROM.
In some embodiments, referring to fig. 1, 6 and 9, the indoor unit of the air conditioner further includes a frequency converter 9, which is respectively connected to the dc bus electrolytic capacitor C1 of the high-voltage dc circuit 1, the dc fan 4 and the controller 5, and the controller 5 controls connection or disconnection of each path of the frequency converter 9, so as to change the direction and frequency of the power supplied to the dc fan 4 by the high-voltage dc circuit 1, and start, increase, decrease or stop the operation of the dc fan 4.
When the controller 5 controls the frequency converter 9 to operate to stop the operation of the direct current fan 4, the controller 5 controls each path of operation of the frequency converter 9 to enable the counter electromotive force generated by the direct current fan 4 in the process of stopping rotation to charge the high voltage direct current circuit 1.
The air-conditioning indoor unit of the embodiment charges the high-voltage direct-current circuit 1 through the counter electromotive force generated in the stopping process of the direct-current fan 4, prolongs the power supply time of the high-voltage direct-current circuit 1 for the controller 5 and the electronic expansion valve 7 after the power failure, and improves the reliability of the execution of the power failure control logic of the controller 5.
In some embodiments, referring to fig. 9, the indoor unit of the air conditioner further includes a current detection circuit 30, which is respectively connected to the controller 5, the inverter 9, and the dc bus electrolytic capacitor C1, and is located between the dc bus electrolytic capacitor C1 and the inverter 9, for measuring the current between the dc bus electrolytic capacitor C1 and the inverter 9 and transmitting the measured current to the controller 5.
The controller 5 is configured with a voltage preset value and a current preset value; the controller 5 controls the duty ratio of the passage of the frequency converter 9 according to the rotation speed of the direct current fan 4, so that the voltage of the direct current bus electrolytic capacitor C1 does not exceed a voltage preset value and the charging current does not exceed a current preset value.
The embodiment can prolong the power supply time of the high-voltage direct-current circuit 1 to the controller 5, protect the direct-current bus electrolytic capacitor C1, and improve the reliability and the service life of the indoor unit of the air conditioner.
In one embodiment, the control configuration is configured with a current low threshold; when the voltage of the direct current bus electrolytic capacitor C1 is not increased any more or the current supplied by the counter electromotive force to the direct current bus electrolytic capacitor C1 is smaller than the current low threshold value, the control circuit controls the disconnection of each path of the frequency converter 9, finishes the charging of the counter electromotive force to the direct current bus electrolytic capacitor C1 and prevents the electric energy of the high-voltage direct current circuit 1 from being consumed reversely.
In an embodiment, referring to fig. 10, the communication of each path of the lower arm of the frequency converter 9 is controlled, and the electrolytic capacitor C1 of the direct current bus is charged when the W-phase current is maximum; of course, the duty ratio of each path of communication of the lower arm of the frequency converter 9 is controlled, and the charging voltage and current are controlled.
In some embodiments, referring to fig. 1, 6 and 9, the air conditioning indoor unit further includes a frequency converter driving circuit 10 and an electronic expansion valve driving circuit 20; the frequency converter 9 is connected with the controller 5 through a frequency converter driving circuit 10, and is used for controlling the connection and disconnection of each path of the frequency converter 9 by the controller 5; the electronic expansion valve 7 is connected to the controller 5 through an electronic expansion valve driving circuit 20, and is used for the controller 5 to control the opening degree change of the electronic expansion valve 7.
In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (10)

1. An indoor unit of an air conditioner is characterized by comprising a high-voltage direct current circuit, a low-voltage direct current circuit, an electric signal detection circuit, a direct current fan, an electronic expansion valve, a controller and at least one low-voltage load;
the high-voltage direct current circuit is respectively connected with the low-voltage direct current circuit, the electric signal detection circuit and the direct current fan; the controller is respectively connected with the direct current fan, the low-voltage direct current circuit, the electronic expansion valve and the low-voltage load and respectively controls the power supply and the operation of the direct current fan, the electronic expansion valve and the low-voltage load;
the electric signal detection circuit detects a voltage signal or a current signal and transmits the voltage signal or the current signal to the controller; the controller judges whether to cut off the power supply according to the received voltage signal or the current signal; and when the controller judges that the power is off, the direct current fan and the low-voltage load are controlled to stop running, and the electronic expansion valve is controlled to be closed.
2. The indoor unit of claim 1, wherein the electric signal detection circuit comprises a dc voltage detection circuit that detects a voltage of the high-voltage dc circuit, records the voltage as a dc voltage, and transmits the dc voltage to the controller;
the controller is configured with a power-down slope limit value and normal voltage; the controller calculates a power-down slope according to the direct-current voltage, and compares the power-down slope with a power-down slope limit value and the direct-current voltage with the normal voltage;
and when the power failure slope is larger than the power failure slope limit value and the direct current voltage is smaller than the normal voltage, controlling the direct current fan to operate in a frequency reduction mode.
3. The indoor unit of claim 2, wherein the down conversion rate of the dc fan is positively correlated to the power down slope during the down conversion operation of the dc fan.
4. An indoor unit of an air conditioner as claimed in claim 2, wherein the controller is configured with an under-voltage limit, and determines whether to power off according to the dc voltage and the under-voltage limit;
when the direct current voltage is smaller than the under-voltage limit value, the controller judges that the power is cut off, controls the direct current fan and the low-voltage load to stop running, and controls the electronic expansion valve to be closed.
5. An indoor unit of an air conditioner according to claim 4, wherein the electric signal detection circuit further includes an AC detection circuit connected to the controller and the HVDC circuit, for detecting an electric signal of a supply AC connected to the HVDC circuit;
the alternating current detection circuit sends the electric signal to the controller; the controller judges whether the power is off or not according to the electric signal;
and when the controller judges that the power is off, the direct current fan and the low-voltage load are controlled to stop running, and the electronic expansion valve is controlled to be closed.
6. The indoor unit of an air conditioner according to claim 4 or 5, further comprising a communication module connected to the controller for communication with an outdoor unit;
when the controller judges that the power is off, the communication module is controlled to send a power-off signal for the outdoor unit to control the compressor to stop running;
and the controller controls the communication module to stop working after the power-off signal is sent.
7. An indoor unit of an air conditioner according to claim 4 or 5, further comprising a power-down memory connected to the controller;
when the controller judges that the power is cut off, the power failure memory is controlled to store the set states of the direct current fan, the electronic expansion valve and the low-voltage load before the power is cut off;
when the electric signal or the direct current voltage returns to normal in a short time and keeps for a specified time, the controller controls the direct current fan, the electronic expansion valve and the low-voltage load to return to the set state before power failure.
8. An indoor unit of an air conditioner according to claim 4 or 5, further comprising an inverter connected to the high voltage dc circuit, the dc fan, and the controller, respectively;
the controller controls the connection or disconnection of each path of the frequency converter, and changes the connection state of the high-voltage direct-current circuit and the direct-current fan;
and when the controller judges that the power is off, the controller controls the connection or disconnection of each path of the frequency converter to stop the direct current fan, and the back electromotive force of the direct current fan charges the high-voltage direct current circuit.
9. An indoor unit of an air conditioner according to claim 8, further comprising a current detection circuit; the high-voltage direct current circuit comprises a direct current bus electrolytic capacitor which is connected with the frequency converter;
the current detection circuit is respectively connected with the controller, the frequency converter and the direct-current bus electrolytic capacitor, and is used for detecting the current between the frequency converter and the direct-current bus electrolytic capacitor and transmitting the current to the controller;
the controller is configured with a voltage preset value and a current preset value; when the direct current fan stops running, the controller controls the duty ratio of the passage of the frequency converter according to the rotating speed of the direct current fan, so that the voltage of the electrolytic capacitor of the direct current bus does not exceed the preset voltage value, and the charging current does not exceed the preset current value.
10. The indoor unit of claim 9, wherein the controller is configured with a current low threshold and compares the current between the inverter and the dc bus electrolytic capacitor with the current low threshold;
when the voltage of the direct current bus electrolytic capacitor is not increased any more or the current supplied to the direct current bus electrolytic capacitor by the counter electromotive force is smaller than the current low threshold value, the controller controls the passage of the frequency converter to be closed.
CN202111234220.7A 2021-10-22 2021-10-22 Indoor unit of air conditioner Active CN113883703B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115371202A (en) * 2022-08-29 2022-11-22 四川虹美智能科技有限公司 Intelligent air conditioner abnormal power-off resetting device and method thereof

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101124436A (en) * 2004-08-11 2008-02-13 L·卡特斯 Method and apparatus for monitoring refrigerant-cycle systems
CN101282090A (en) * 2007-04-04 2008-10-08 张亦翔 Capacitance partial pressure DC voltage stabilizing power source
JP2013060144A (en) * 2011-09-14 2013-04-04 Denso Corp Vehicular air conditioner
CN103292448A (en) * 2013-05-30 2013-09-11 华为技术有限公司 Method and device for preventing condensation of refrigerating device
CN108109568A (en) * 2018-01-10 2018-06-01 京东方科技集团股份有限公司 Power supply adjusting circuit and method, test system
CN110094861A (en) * 2019-06-04 2019-08-06 珠海格力电器股份有限公司 Refrigeration system
CN110094857A (en) * 2019-04-11 2019-08-06 海信（山东）空调有限公司 Control method, device, computer product and the air-conditioning of air conditioner electronic expansion valve
US20210247120A1 (en) * 2020-02-11 2021-08-12 Lg Electronics Inc. Power converting apparatus and air conditioner including the same

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101124436A (en) * 2004-08-11 2008-02-13 L·卡特斯 Method and apparatus for monitoring refrigerant-cycle systems
CN101282090A (en) * 2007-04-04 2008-10-08 张亦翔 Capacitance partial pressure DC voltage stabilizing power source
JP2013060144A (en) * 2011-09-14 2013-04-04 Denso Corp Vehicular air conditioner
CN103292448A (en) * 2013-05-30 2013-09-11 华为技术有限公司 Method and device for preventing condensation of refrigerating device
CN108109568A (en) * 2018-01-10 2018-06-01 京东方科技集团股份有限公司 Power supply adjusting circuit and method, test system
CN110094857A (en) * 2019-04-11 2019-08-06 海信（山东）空调有限公司 Control method, device, computer product and the air-conditioning of air conditioner electronic expansion valve
CN110094861A (en) * 2019-06-04 2019-08-06 珠海格力电器股份有限公司 Refrigeration system
US20210247120A1 (en) * 2020-02-11 2021-08-12 Lg Electronics Inc. Power converting apparatus and air conditioner including the same

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115371202A (en) * 2022-08-29 2022-11-22 四川虹美智能科技有限公司 Intelligent air conditioner abnormal power-off resetting device and method thereof

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