KR20000075242A - Frosting/defrosting method for inverter heat pump air conditioner - Google Patents

Frosting/defrosting method for inverter heat pump air conditioner Download PDF

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KR20000075242A
KR20000075242A KR1019990019747A KR19990019747A KR20000075242A KR 20000075242 A KR20000075242 A KR 20000075242A KR 1019990019747 A KR1019990019747 A KR 1019990019747A KR 19990019747 A KR19990019747 A KR 19990019747A KR 20000075242 A KR20000075242 A KR 20000075242A
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South Korea
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frequency
defrosting operation
defrosting
compressor
outdoor
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KR1019990019747A
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Korean (ko)
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KR100585683B1 (en
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김양규
김철민
박종한
황윤제
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구자홍
엘지전자 주식회사
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00Control or safety arrangements
    • F24F11/30Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
    • F24F11/41Defrosting; Preventing freezing
    • F24F11/42Defrosting; Preventing freezing of outdoor units
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F2110/00Control inputs relating to air properties
    • F24F2110/10Temperature
    • F24F2110/12Temperature 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)
  • Air Conditioning Control Device (AREA)

Abstract

PURPOSE: A defrost control method is provided to minimize user inconvenience and improve efficiency and reliability of system by accurately recognizing the time of frost formation at an outdoor heat exchanger. CONSTITUTION: A method comprises a first step of classifying outdoor temperature into three sections and starting a defrosting operation with different compressor operation time and pipeline temperature for each of the three sections, a second step of lowering, if it is judged as a defrosting operation, operation frequency to a minimum frequency for outdoor control, switching linear expansion valve, and performing defrosting operation at an operation frequency for a predetermined time period if the operation frequency at the start of defrosting operation is higher than a predetermined frequency, a third step of switching a four-way valve, performing defrosting operation at the lowest frequency during a predetermined time period, and performing defrosting operation at a high frequency, and a fourth step of turning off a compressor during a predetermined time period when the defrosting operation is completed.

Description

인버터 히트펌프 냉난방장치의 착제상방법{FROSTING/DEFROSTING METHOD FOR INVERTER HEAT PUMP AIR CONDITIONER}Inverter Heat Pump Air Conditioning Method {FROSTING / DEFROSTING METHOD FOR INVERTER HEAT PUMP AIR CONDITIONER}

본 발명은 인버터 히트펌프 냉난방장치의 착제상방법에 관한 것으로, 특히 팽창장치로 전자팽창변(Linear Expansion Valve)을 사용하는 인버터 히트펌프 냉난방장치에 있어서, 실외 교환기에 서리가 방생할 때 이를 검지하여 제거하는 인버터 히트펌프 냉난방장치의 착제상방법에 관한 것이다.The present invention relates to a method of landing on an inverter heat pump air conditioner, and more particularly, in an inverter heat pump air conditioner that uses an electronic expansion valve as an expansion device, and detects and removes frost when an outdoor exchange occurs. The present invention relates to a method of landing on an inverter heat pump cooling and heating device.

냉난방을 동시에 겸할 수 있는 냉난방장치(이하 "에어컨"이라 약칭함)를 히트펌프 에어컨이라 하는데, 냉방전용 에어컨의 구성에 사방변을 추가시켜 사방변 절환에 의한 냉난방 역활을 수행하도록 할 수 있는 것으로, 그의 구성은 도 1에 도시된 바와 같이 저온, 저압의 냉매증기를 흡입하여 이를 압축함으로써 고온, 고압의 증기로 만드는 압축기(11)와; 난방 시 상기 압축기(11)에서 토출된 고온, 고압의 냉매증기의 열을 물 또는 공기 중에 방출시키고, 고압의 포화액으로 변화시키는 응축기로 쓰이는 실외 열교환기(12)와; 냉방 시 저온, 저압의 냉매를 증발시켜 액분이 없는 포화증기로 만드는 증발기로 쓰이는 실내 열교환기(14)와; 냉매의 흐름 압력을 조절하는 팽창변(16) 및 이들을 연결하여 주는 배관으로 구성된 냉동 사이클의 냉매의 흐름을 역으로 바꾸어 운전시키는 사방변(17)으로 구성된다.An air-conditioning unit (abbreviated as "air conditioner"), which can also function as both air conditioning and heating, is called a heat pump air conditioner. By adding four sides to the configuration of the air conditioner for cooling, it is possible to perform the role of cooling and heating by switching the four sides, As shown in FIG. 1, the compressor 11 includes a compressor 11 which makes steam of high temperature and high pressure by sucking and compressing refrigerant vapor of low temperature and low pressure; An outdoor heat exchanger (12) used as a condenser for dissipating heat of the high-temperature and high-pressure refrigerant vapor discharged from the compressor (11) into water or air and changing the saturated high-pressure liquid into a high-pressure saturated liquid; An indoor heat exchanger (14) used as an evaporator to evaporate a low-temperature, low-pressure refrigerant to cool the liquid vapor without saturated liquid; Expansion valve 16 for adjusting the flow pressure of the refrigerant and the four sides of the refrigerant 17 of the refrigeration cycle of the refrigeration cycle composed of pipes connecting them to reverse the operation of the four sides.

이와 같이 구성된 종래 장치의 동작 과정을 설명하면 다음과 같다.Referring to the operation of the conventional device configured as described above are as follows.

히트펌프 에어컨은 겨울철 외기온이 5℃ 이하가 되고, 습구온도가 높으면 실외 열교환기(12)에 서리가 생기는 착상현상이 일어나는데, 착상이 일어나면 실외 열교환기(12)의 성능이 저하되어 공조부하에 필요한 열량을 시스템에서 내줄 수 없게 된다, 이런 경우를 방지하기 위해 발생한 서리를 제거하는 운전을 수행하게 되며, 이를 제상운전이라고 한다.In the heat pump air conditioner, the outdoor air temperature is 5 ° C. or less in winter, and if the wet bulb temperature is high, the frost phenomenon occurs in the outdoor heat exchanger 12. When the formation occurs, the performance of the outdoor heat exchanger 12 is deteriorated. The calories cannot be delivered from the system. To prevent this, the defrosting operation is performed. This is called defrosting.

인버터가 아닌 정속 히트펌프 에어컨의 경우에는 도 1의 팽창변(16)을 모세관으로 사용하나 인버터 에어컨의 경우에는 가변 유량폭이 매우 커짐으로 전자팽창변을 사용한다.In the case of a constant speed heat pump air conditioner other than an inverter, the expansion valve 16 of FIG. 1 is used as a capillary tube. However, in the case of an inverter air conditioner, an electronic expansion valve is used because the variable flow width becomes very large.

인버터 에어컨의 경우 제상시에는 대부분 사방변을 절환하는 역 사이클 운전을 하고 있으며, 이때 제상운전 시작 시기는 여러가지 조건으로 판단할 수 있지만 크게 3가지 방법으로 판단하는데, 첫 번째 운전조건이 착상영역에 들어가면 일정시간 운전 후 제상운전을 실시하는 방법과, 두 번째 운전조건이 착상영역에 들어간 후 배관온도(실외 열교환기) 값의 변화가 일정시간동안 일정한 값 이상이 되면 제상운전에 들어가는 방법과, 세 번째 운전조건이 착상영역에 들어간 후 실외온도와 배관온도의 차가 일정시간동안 일정한 값 이상이 되면 제상운전에 들어가는 방법이 있다.In case of inverter air conditioner, most of the time, defrosting is performed in reverse cycle operation to switch the four sides.In this case, the start time of defrosting operation can be judged by various conditions, but it is judged by three methods. Defrosting operation after a certain period of time, and if the change of the pipe temperature (outdoor heat exchanger) value exceeds a certain value for a certain period of time after the second operation condition enters the frosting area, If the difference between the outdoor temperature and the pipe temperature exceeds a certain value for a certain time after the operation condition enters the frosting area, there is a method of defrosting.

그리고, 제상운전의 종료시점은 대부분 제상운전 시간이 일정시간 지났거나 배관온도가 일정한 값 이상으로 올라갔을 때로 하고 있다.Most of the end points of the defrosting operation are when the defrosting operation time has elapsed for a certain time or the piping temperature has risen above a certain value.

상기에서와 같이 종래의 기술에 있어서는 제상검지를 제대로 하지 못하여 착상이 되지 않은 경우에도 제상운전을 수행하고, 제상 시 압축기로 액이 리턴되어 압축기의 신뢰성이 저하되며, 제상 시작시 주파수의 급격한 변화로 인하여 시스템이 불안정하고, 이에 따라 압축기가 정지하는 일이 발생하는 문제점이 있었다.As described above, in the prior art, even when defrosting is not performed properly, defrosting is performed, and liquid is returned to the compressor at the time of defrosting, thereby degrading the reliability of the compressor and causing a sudden change in frequency at the start of defrosting. Due to the system is unstable, there is a problem that the compressor is stopped accordingly.

따라서, 본 발명은 상기와 같은 종래의 문제점을 해결하기 위하여 창안한 것으로, 실외 열교환기에 착상이 발생하는 시점을 정확히 파악하여 빠른 시간내에 제상운전을 수행하도록 하는 방법을 제공함에 그 목적이 있다.Accordingly, the present invention has been made to solve the above-described problems, and an object of the present invention is to provide a method of accurately determining the timing at which an frosting occurs in an outdoor heat exchanger and performing a defrosting operation in a short time.

도 1은 종래 히트펌프 에어컨의 구성을 보인 예시도.1 is an exemplary view showing a configuration of a conventional heat pump air conditioner.

도 2는 본 발명을 적용한 제상사이클을 보인 예시도.2 is an exemplary view showing a defrost cycle to which the present invention is applied.

*** 도면의 주요 부분에 대한 부호의 설명 ****** Explanation of symbols for the main parts of the drawing ***

11 : 압축기 12 : 실외 열교환기11: compressor 12: outdoor heat exchanger

13 : 실외 팬 14 : 실내 열교환기13: outdoor fan 14: indoor heat exchanger

15 : 실내 팬 16 : 팽창변15: indoor fan 16: expansion valve

17 : 사방변17: all sides

이와 같은 목적을 달성하기 위한 본 발명 인버터 히트펌프 냉난방장치의 착제상방법은 실외온도를 3가지 영역으로 나누어 각기 압축기 운전시간 및 배관온도를 달리하여 제상운전을 시작하도록 하는 제상운전개시단계와; 제상운전이 판단되면 운전주파수를 실외제어 최저주파수로 낮추고 전자변을 절환한 후, 제상운전개시 시점에서 운전주파수가 소정 주파수보다 높으면 그 주파수에서 일정시간동안 운전하는 제상운전예비단계와; 사방변 절환하여 일정시간 동안 최저주파수로 운전한 후, 고주파수로 운전하여 제상운전을 시작하는 제상운전수행단계와; 제상운전이 종료되면 압축기를 소정시간 정지시키고, 운전주파수가 하강할 때 소정 주파수까지 제상직전의 전자변 개도를 유지시킨 후, 최저주파수로 운전될때까지 최저주파수 시 설정된 전자변 개도로 운전하는 전자변 개도제어를 특징으로 한다.The defrosting method of the present invention for achieving the above object is a defrosting operation step of starting the defrosting operation by dividing the outdoor temperature into three zones and varying the compressor operation time and the piping temperature; When the defrosting operation is determined, the operation frequency is lowered to the lowest outdoor control frequency, the electronic valve is switched, and the defrosting operation preliminary operation is performed for a predetermined time at the frequency when the operation frequency is higher than the predetermined frequency at the start of the defrosting operation; A defrosting operation performing step of switching in all directions and driving at the lowest frequency for a predetermined time and then driving at a high frequency to start defrosting operation; When the defrosting operation is completed, the compressor is stopped for a predetermined time, and when the operating frequency falls, the electronic shift control that maintains the electronic shift degree just before the defrost until the predetermined frequency is operated, and operates with the electronic shift set at the lowest frequency until it is operated at the lowest frequency. It features.

이하, 본 발명에 따른 일실시예를 첨부한 도면을 참조하여 상세히 설명하면 다음과 같다.Hereinafter, an embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

도 2는 본 발명을 적용한 제상사이클을 보인 예시도로서, 이에 도시한 바와 같이 실외온도(외기온도)를 3구간으로 나누어 실외온도가 A값보다 클 경우에 압축기(11)를 가동한 후, 적산시간이 C이상이고, 배관온도(실외 열교환기 온도)가 F이하이면 제상운전에 들어가며, 실외온도가 B와 A사이의 경우에는 압축기(11)를 가동한 후 적산시간 D이상이고, 배관온도가 G이하이면 제상운전에 들어가며, 또한 실외온도가 B이하이면 압축기(11)를 가동한 후, 적산시간이 E이상이고 배관온도가 H이하이면 제상운전에 들어간다(실외온도를 3가지 영역으로 나누는 이유는 실외온도에 따라 공기 중의 수분량인 절대습도가 크게 달라 착상메카니즘이 달라지기 때문에 이를 방지하기 위함이다).2 is an exemplary view showing a defrost cycle to which the present invention is applied. As shown in FIG. 2, the outdoor temperature (outside air temperature) is divided into three sections, and when the outdoor temperature is greater than the A value, the compressor 11 is integrated. If the time is more than C and the piping temperature (outdoor heat exchanger temperature) is less than or equal to F, the defrosting operation is started. If the outdoor temperature is between B and A, the compressor 11 is operated and the integration time is more than D. If the temperature is lower than G, the defrosting operation is performed. If the outdoor temperature is lower than B, the compressor 11 is operated. If the integration time is higher than E and the piping temperature is lower than H, the defrosting operation is started. This is to prevent this problem because the concept of the mechanism of implantation varies greatly depending on the outdoor temperature.

일단 제상운전에 들어가면 운전주파수를 낮추는데, 이는 사방변(17)을 전환할 때 사방변 전,후단의 압비를 최소화하여 사방변(17) 전환 시 발생되는 오동작을 방지하고, 증발온도 및 응축온도를 사방변 절환후에 형성되는 사이클온도에 맞추기 위해서이다.Once the defrosting operation is entered, the operation frequency is lowered, which minimizes the pressure ratio of the front and rear sides of the four sides when switching the four sides, thereby preventing malfunctions caused by the four sides of the four sides, and reducing the evaporation temperature and the condensation temperature. This is to match the cycle temperature formed after the four-sided changeover.

사방변 절환은 운전주파수가 c가된 후, d초후에 이루어지며, 운전주파수를 b에서 c로 낮출 때 b가 72Hz 이상이면 72Hz에서 30초간 운전한 후(운전주파수를 급격히 낮추면 압축기가 이에 대응하지 못하여 무리한 부하를 받아 시스템이 정지하는 경우를 방지하기 위한 운전), c로 다시 운전주파수를 하강한다.Four-way switching takes place after d seconds after the operating frequency becomes c, and when the operating frequency is lowered from b to c, if b is greater than 72 Hz, it operates for 30 seconds at 72 Hz (if the operating frequency is sharply lowered, the compressor does not respond to this). Operation to prevent the system from being stopped due to unreasonable load), and the operation frequency is lowered to c again.

운전주파수가 실온제어 최저주파수로 하강하면 d초간 운전한 후, 사방변을 절환하고, 사방변이 절환될 때 실내외 팬(13, 15)은 정지시킨다. 사방변 절환 후 e분간 최저주파수로 운전하고, 그 후 a 주파수로 상승시킨다.When the operation frequency drops to the lowest room temperature control frequency, the operation is performed for d seconds, and then the four sides are switched, and when the four sides are switched, the indoor and outdoor fans 13 and 15 are stopped. After switching on all sides, operate at the lowest frequency for e minutes and then increase to the frequency a.

전자변 개도는 72Hz까지는 제상 직전의 값을 유지하고 그 다음부터 제상운전 시 a 주파수로 상승할 때까지 h개도값을 가진다(주파수가 a일때는 실온제어 시 개도값보다 큰 값으로 설정한다).The electromagnetic opening degree maintains the value immediately before defrosting up to 72 Hz and has a value of h opening until it rises to the a frequency during defrosting operation (when the frequency is a, set to a value larger than the opening value at room temperature control).

제상종료 시점은 실외배관온도가 12℃가 되든지 제상운전시간이 10분이 지난 시점 중 먼저 발생하는 때로 하며, 제상운전이 종료되면 압축기를 30초간 정지시킨다. 이때 전자변 개도는 제상운전 중의 a 주파수일 때의 값을 유지하고, 실내 팬(15)은 정지한 상태를 유지시키며, 실외 팬(13)은 동작을 시킨다.Defrost end time occurs when the outdoor piping temperature is 12 ℃ or when the defrosting operation time is 10 minutes later, stop the compressor for 30 seconds when the defrosting operation is finished. At this time, the electromagnetic opening degree maintains the value at the a frequency during the defrosting operation, the indoor fan 15 remains stopped, and the outdoor fan 13 operates.

이상에서 설명한 바와 같이 본 발명 인버터 히트펌프 냉난방장치의 착제상방법은 실외 열교환기에 착상이 발생하는 조건에 의한 제상개시 시점을 정확히 파악하여 제상운전에 들어가 빠른 시간내에 제상운전을 종료함으로써, 사용자에게 제상 시 난방을 공급받지 못하는 불편함을 없애며, 압축기에 무리를 주지 않고 제상운전을 하기 때문에 시스템의 효율성 및 신뢰성을 향상시키는 효과가 있다.As described above, the defrosting method of the inverter heat pump air-conditioning apparatus of the present invention accurately detects the start point of defrosting due to the condition in which the defrosting occurs in the outdoor heat exchanger, enters the defrosting operation, and finishes the defrosting operation in a short time. Eliminates the inconvenience of not receiving the heating, and defrosting the compressor without affecting the system has the effect of improving the efficiency and reliability of the system.

Claims (2)

실외온도를 3가지 영역으로 나누어 각기 압축기 운전시간 및 배관온도를 달리하여 제상운전을 시작하도록 하는 제상운전개시단계와; 제상운전이 판단되면 운전주파수를 실외제어 최저주파수로 낮추고 전자변을 절환한 후, 제상운전개시 시점에서 운전주파수가 소정 주파수보다 높으면 그 주파수에서 일정시간동안 운전하는 제상운전예비단계와; 사방변 절환하여 일정시간 동안 최저주파수로 운전한 후, 고주파수로 운전하여 제상운전을 시작하는 제상운전수행단계와; 제상운전이 종료되면 압축기를 소정시간 정지시키고, 운전주파수가 하강할 때 소정 주파수까지 제상직전의 전자변 개도를 유지시킨 후, 최저주파수로 운전될때까지 최저주파수 시 설정된 전자변 개도로 운전하는 전자변 개도제어를 특징으로 하는 인버터 히트펌프 냉난방장치의 착제상방법.A defrosting operation starting step of dividing the outdoor temperature into three areas to start defrosting operation by varying compressor operating time and piping temperature; When the defrosting operation is determined, the operation frequency is lowered to the lowest outdoor control frequency, the electronic valve is switched, and the defrosting operation preliminary operation is performed for a predetermined time at the frequency when the operation frequency is higher than the predetermined frequency at the start of the defrosting operation; A defrosting operation performing step of switching in all directions and driving at the lowest frequency for a predetermined time and then driving at a high frequency to start defrosting operation; When the defrosting operation is completed, the compressor is stopped for a predetermined time, and when the operating frequency falls, the electronic shift control that maintains the electronic shift degree just before the defrost until the predetermined frequency is operated, and operates with the electronic shift set at the lowest frequency until it is operated at the lowest frequency. A method of landing on an inverter heat pump air conditioner. 제1항에 있어서, 상기 제상운전예비단계는 운전주파수를 급격히 낮추면 압축기가 이에 대응하지 못하여 무리한 부하를 받아 시스템이 정지하는 경우를 방지하기 위하여 운전주파수가 72Hz보다 높으면 72Hz에서 30초간 운전하는 것을 특징으로 하는 인버터 히트펌프 냉난방장치의 착제상방법.The method of claim 1, wherein the defrosting operation preliminary step is to operate for 30 seconds at 72Hz when the operating frequency is higher than 72Hz to prevent the system stops under excessive load because the compressor does not correspond to this if the operating frequency is sharply lowered. Method of landing on the inverter heat pump air-conditioning device using
KR1019990019747A 1999-05-31 1999-05-31 Frosting/defrosting method for inverter heat pump air conditioner KR100585683B1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112944753A (en) * 2019-12-11 2021-06-11 杭州三花研究院有限公司 Control system and control method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112944753A (en) * 2019-12-11 2021-06-11 杭州三花研究院有限公司 Control system and control method thereof

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