Heat pump air conditioner capable of eliminating system circulation ice blockage

Abstract

The invention relates to a heat pump air conditioner capable of eliminating system circulation ice blockage, which comprises a compressor, a four-way valve, a water side heat exchanger, an electronic expansion valve, an air side heat exchanger and a pressure detection module, the ice blockage monitoring system comprises a compressor, a pressure detection module used for monitoring high pressure and low pressure, a temperature detection module used for monitoring return air temperature and environment temperature, and a controller in communication connection with the compressor, the pressure detection module and the temperature detection module, a heating belt is arranged on an air distribution part of the compressor, and the ice blockage condition of the system is judged through the pressure difference between the high pressure and the low pressure and the temperature difference between the return air temperature and the environment temperature. According to the method, whether circulating ice blockage occurs in the system or not can be accurately judged, the problems of no ice blockage heating, no heating with ice blockage or incomplete and unbalanced ice blockage heating in an existing control method can be solved, circulating ice blockage of the system can be effectively prevented and eliminated, the energy efficiency of the heat pump air conditioner can be improved, and energy is saved.

Description

Technical Field

[0001] The invention relates to the control field of heat pump air conditioners, and in particular to a heat pump air conditioner capable of eliminating ice blockage in system circulation. Background Art

[0002] When the water content of the refrigerant in the heat pump air conditioning unit exceeds the standard, as the refrigerant circulates, the water will gradually gather and freeze in the low temperature area of ​​the unit, blocking the valve port or the refrigerant circulation pipeline, causing the refrigerant circulation to be interrupted. When the water-containing refrigerant freezes at the gas distribution of the compressor, the refrigerant will not be able to pass through the filter to enter the compressor for compression, causing the entire unit to be in a state of insufficient refrigerant. As a result, during the operation of the entire heat pump air conditioning unit, the compressor will run continuously for a long time, but the unit will not cool, heat, or cool and heat slowly, and other situations will occur. At the same time, the exhaust pressure of the unit will increase, the suction pressure will decrease, affecting the stable operation of the system, and even increasing the power consumption and load of the compressor, causing the compressor to overheat or damage.

[0003] In order to solve the problem of ice blockage in the gas distribution of the compressor, filter drying and heating drying are usually used to eliminate ice blockage. The filter drying method requires regular replacement of the drying filter. If the replacement is not timely, ice blockage will still occur, and the cost of use is relatively high. The heating drying method usually installs a heating device at the bottom or shell of the compressor, and detects the outdoor temperature through a sensor. When the outdoor temperature is lower than the starting threshold of the heating device, the heating device is controlled to start to maintain the temperature of the compressor to avoid ice blockage. This method is prone to inaccurate judgment of ice blockage, resulting in heating without ice blockage, no heating with ice blockage, or incomplete and unbalanced heating of ice blockage, which increases the operating cost and power loss of the compressor, reduces the energy efficiency of the unit, and causes energy waste. Summary of the invention

[0004] Based on this, an object of the present invention is to provide a heat pump air conditioner that can eliminate ice blockage in system circulation.

[0005] A heat pump air conditioner capable of eliminating ice blockage in system circulation comprises a compressor, a four-way valve, a water-side heat exchanger, an electronic expansion valve, an air-side heat exchanger connected through a refrigerant circulation pipeline, and a pressure detection module for monitoring the high exhaust pressure and the low intake pressure of the compressor, and a temperature detection module for monitoring the return air temperature and the ambient temperature, and a controller communicatively connected with the compressor, the pressure detection module, and the temperature detection module. A heating belt is arranged in the gas division of the compressor, and the controller controls the start of the heating belt through the following steps:

[0006] After the compressor starts running for the first time period t1, the current high pressure of the compressor is obtained. Low pressure at this moment Current return air temperature and the current ambient temperature

[0007] Calculate the current high pressure Low pressure at this moment The current pressure difference And the current return air temperature and the current ambient temperature The current temperature difference

[0008] Determine the current pressure difference Is it less than the set start pressure difference threshold ΔP? target , and the temperature difference at the current time Is it less than the set start temperature difference threshold?

[0009] If yes, start the heating belt of the gas section of the compressor;

[0010] In other cases, continue to obtain the next moment of high pressure Next moment low pressure Return air temperature at next moment and the ambient temperature at the next moment

[0011] Compared with the prior art, the heat pump air conditioner of the present invention can eliminate system circulation ice blockage by arranging a heating belt in the compressor gas section, and jointly judging the system ice blockage situation through the pressure difference between high pressure and low pressure, and the temperature difference between return air temperature and ambient temperature. It can make an accurate judgment on whether the system has circulation ice blockage, and can avoid the problems of heating without ice blockage, no heating with ice blockage, or incomplete and unbalanced heating with ice blockage in the prior control methods. It can effectively prevent and eliminate system circulation ice blockage, and can improve the energy efficiency of the heat pump air conditioner and save energy.

[0012] Furthermore, the heating belt is arranged in the upper chamber of the gas division of the compressor and surrounds the upper chamber.

[0013] Furthermore, a filter is arranged before the electronic expansion valve.

[0014] Furthermore, the controller also includes controlling the closing of the heating belt:

[0015] Get the current return air temperature and the current ambient temperature Calculate the return air temperature at the current moment and the current ambient temperature The current temperature difference

[0016] Determine the temperature difference at the current moment Is it greater than the set shutdown temperature difference threshold?

[0017] If yes, turn off the heating belt of the gas section of the compressor;

[0018] If not, continue to obtain the return air temperature at the next moment and the ambient temperature at the next moment

[0019] For better understanding and implementation, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of an embodiment of the present invention;

[0021] Figure 2 A flowchart of controlling the start-up of a heating belt according to an embodiment of the present invention;

[0022] Figure 3 This is a flow chart of controlling the heating belt to shut down according to an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention.

[0024] In order to solve the existing problem of adding a heating device at the bottom or outside of the compressor to solve the problem of ice blockage at the air branch of the compressor of the heat pump unit, the ambient temperature is monitored to start and stop the heating device, resulting in heating without ice blockage, no heating with ice blockage, or incomplete and unbalanced heating due to ice blockage. After research and design, the present invention proposes a heat pump air conditioner that can eliminate system circulation ice blockage. The heat pump air conditioner is provided with an annular heating belt on the compressor air branch and a method for controlling the start and stop of the environmental heating belt, which can effectively prevent and eliminate the problem of system circulation ice blockage in the heat pump air conditioner. The heat pump air conditioner has a simple heating setting and a simple and reliable control method, and can make an accurate judgment on whether the system has circulation ice blockage. On this basis, it can effectively prevent and eliminate system circulation ice blockage in the heat pump air conditioner, save energy, and improve the energy efficiency of the heat pump air conditioner.

[0025] For specific implementation, see Figure 1 The heat pump air conditioner proposed by the present invention can eliminate the ice blockage of the system circulation, including a compressor 10, a four-way valve 20, a water-side heat exchanger 30, an electronic expansion valve 40, an air-side heat exchanger 50 and a gas-liquid separator 60 connected through a refrigerant circulation pipeline, and a pressure detection module 70 for monitoring the high exhaust pressure and low intake pressure of the compressor 10, and a temperature detection module 80 for monitoring the return air temperature and the ambient temperature, and a controller communicatively connected to the compressor 10, the pressure detection module 70, and the temperature detection module 80.

[0026] The compressor 10 includes an exhaust port A and a return port B, wherein the return port B is connected to the gas-liquid separator 60 through a gas separation section 11. The gas separation section 11 includes an upper chamber and a lower chamber. The upper chamber is connected to the gas-liquid separator 60, and the lower chamber is connected to the return port B. A heating belt 12 is provided in the upper chamber of the gas separation section 11, and the heating belt 12 surrounds the gas separation chamber and is controlled to open and close by a controller.

[0027] The pressure detection module 70 includes a first pressure gauge 71 and a second pressure gauge 72. The first pressure gauge 71 is disposed at the exhaust port A of the compressor 10 to detect the high exhaust pressure of the compressor. The second pressure gauge 72 is disposed at the return port B of the compressor 10 to detect the low return pressure of the compressor.

[0028] The temperature detection module 80 includes a first temperature sensor 81 and a second temperature sensor 82. The first temperature sensor 81 is arranged at the compressor return air port B, and is used to detect the return air temperature of the refrigerant. The second temperature sensor 82 is not limited in its arrangement position, and is used to detect the ambient temperature of the environment in which the heat pump air conditioner is located.

[0029] The controller includes a storage unit and a processing unit. The storage unit is used to receive pressure and temperature signals collected by the pressure detection module 70 and the temperature detection module 80; the processing unit is used to perform logical judgment and start and stop control of the heating belt 12 according to the collected signals.

[0030] Furthermore, the heat pump air conditioner capable of eliminating ice blockage in the system circulation further includes a first valve assembly 9 arranged between the water-side heat exchanger 30 and the electronic expansion valve 40 and a second valve assembly 100 arranged between the air-side heat exchanger 50 and the electronic expansion valve 40 .

[0031] The electronic expansion valve 40 includes a first electronic expansion valve 41 and a second electronic expansion valve 42 .

[0032] The first valve assembly 90 includes a first three-way valve 91 connected to the water side heat exchanger 30, a first reverse check valve 92 and a first forward check valve 93 connected to the first three-way valve 91, the first reverse check valve 92 is connected to the first electronic expansion valve 41 through the second three-way valve 94, the first forward check valve 93 is connected to a filter 01 through a third three-way valve 95, the filter 01 is connected to a plate heat exchanger 02, the plate heat exchanger 02 is respectively connected to the first electronic expansion valve 41 and the second electronic expansion valve 42 through a fourth three-way valve 98, the first electronic expansion valve 41 is connected to the second three-way valve 94 to form a main circulation loop, and the second electronic expansion valve 42 is then connected to the compressor 10 via the plate heat exchanger 02 to form an auxiliary circulation loop.

[0033] The second valve assembly 100 includes a fifth three-way valve 101 connected to the air side heat exchanger 50, a second reverse check valve 102 and a second forward check valve 103 connected to the fifth three-way valve 101, the second reverse check valve 102 is connected to the second three-way valve 94, and the second forward check valve 103 is connected to the filter 01 via the third three-way valve 95.

[0034] When the heat pump air conditioner is heating water, the high-temperature refrigerant is converted into a medium-temperature refrigerant after heat exchange with water through the water-side heat exchanger 30. The medium-temperature refrigerant is further heat exchanged through the first three-way valve 91, the first forward check valve 93, the third three-way valve 95, the filter 01 and the plate heat exchanger 02 in sequence, and then throttled and reduced in pressure through the fourth three-way valve 98 and the first electronic expansion valve 41 in sequence, and then flows into the air-side heat exchanger 50 through the second three-way valve 94, the second reverse check valve 102, and the fifth three-way valve 101 for heat absorption and evaporative cooling.

[0035] When the heat pump air conditioner is heating, the high-temperature refrigerant is converted into medium-temperature refrigerant after heat exchange with the air through the air-side heat exchanger 50. The medium-temperature refrigerant is further heat exchanged through the fifth three-way valve 101, the second forward check valve 103, the third three-way valve 95, the filter 01 and the plate heat exchanger 02, and then throttled and reduced in pressure through the fourth three-way valve 98 and the first electronic expansion valve 41, and then flows into the water-side heat exchanger 30 through the second three-way valve 94, the first reverse check valve 92 and the first three-way valve 91 for heat absorption and evaporative cooling.

[0036] When the heat pump air conditioner needs enthalpy increase control, the second electronic expansion valve 42 is opened and its opening is adjusted so that part of the refrigerant throttled by the second electronic expansion valve 42 returns to the plate heat exchanger 02 and exchanges heat with the medium-temperature refrigerant of the plate heat exchanger 02 before directly flowing back to the compressor 10.

[0037] See also Figure 2 At the same time, the controller controls the start-up of the heating belt 12 in the following manner to eliminate the ice blockage of the system circulation. Specifically, the following steps are included.

[0038] S10 After the compressor starts running for the first time period t1, obtain the current high pressure of the compressor Low pressure at this moment Current return air temperature and the current ambient temperature

[0039] The first time period t1 is set to 18 minutes to 22 minutes.

[0040] S20 calculates the current high pressure Low pressure at this moment The current pressure difference And the current return air temperature and the current ambient temperature The current temperature difference

[0041] The pressure difference satisfy:

[0042]

[0043] The temperature difference satisfy:

[0044]

[0045] S30 determines the current pressure difference Is it less than the set start pressure difference threshold ΔP? target , and the temperature difference at the current time Is it less than the set start temperature difference threshold?

[0046] If yes, start the heating belt of the gas section of the compressor;

[0047] In other cases, continue to obtain the next moment of high pressure Next moment low pressure Return air temperature at next moment and the ambient temperature at the next moment

[0048] The starting pressure difference threshold ΔP target Set to 0.3MPa~0.5MPa, preferably 0.4MPa.

[0049] The starting temperature difference threshold Set to 1℃~2℃, preferably 1℃.

[0050] The time interval between the next moment and the current moment is set to 25s to 35s, preferably 30s.

[0051] Furthermore, the method further includes controlling the heating belt to be turned off after eliminating ice blockage in the system circulation to save energy. The method specifically includes the following steps.

[0052] S50 obtains the current return air temperature and the current ambient temperature Calculate the return air temperature at the current moment and the current ambient temperature The current temperature difference

[0053] S60 determines the temperature difference at the current moment Is it greater than the set shutdown temperature difference threshold?

[0054] If yes, turn off the heating belt of the gas section of the compressor;

[0055] If not, continue to obtain the return air temperature at the next moment and the ambient temperature at the next moment

[0056] The shutdown temperature difference threshold Set to 4℃~5℃, preferably 4℃.

[0057] The heat pump air conditioner capable of eliminating ice blockage in system circulation of the present invention has the following beneficial technical effects.

[0058] 1) Through the pressure difference between high pressure and low pressure, and the temperature difference between return air temperature and ambient temperature, it can be effectively determined whether the heat pump air conditioner has the risk of ice blockage and whether there is ice blockage.

[0059] 2) By placing a circle of heating belt in the upper chamber of the compressor gas division, and controlling the opening and closing of the heating belt by combining the pressure difference between high pressure and low pressure, and the temperature difference between the return air temperature and the ambient temperature, the problem of system circulation ice blockage in heat pump air conditioning can be effectively prevented and eliminated.

[0060] 3) By installing a filter before the throttling of the electronic expansion valve, the water content of the refrigerant can be reduced to a certain extent, further reducing the risk of ice blockage in the heat pump air conditioner.

[0061] 4) By arranging a plate heat exchanger between the filter and the electronic expansion valve, cooling capacity can be provided for the refrigerant before throttling, and the heat of the refrigerant before throttling can be transferred to the refrigerant in the compressor, further improving the energy efficiency of the system.

[0062] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the embodiments of the present application. The singular forms of "a", "said" and "the" used in the embodiments of the present application and the claims are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that, unless otherwise specified, "multiple" and "several" refer to two or more; "and / or" refers to and includes any or all possible combinations of one or more associated listed items; "first", "second", "third", etc. are only used to distinguish, rather than to describe a specific order or sequence, and cannot be understood as indicating or implying relative importance. When the above description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. In the description of the present application, for those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0063] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, and the present invention is also intended to include these modifications and modifications.

Claims

1. A heat pump air conditioner capable of eliminating ice blockage in system circulation, comprising a compressor, a four-way valve, a water-side heat exchanger, an electronic expansion valve, an air-side heat exchanger connected through a refrigerant circulation pipeline, and a pressure detection module for monitoring the high exhaust pressure and the low intake pressure of the compressor, and a temperature detection module for monitoring the return air temperature and the ambient temperature, and a controller communicatively connected to the compressor, the pressure detection module, and the temperature detection module, characterized in that: A heating belt is provided in the gas division of the compressor, and the controller controls the start-up of the heating belt through the following steps: After the compressor starts running for the first time period t1, the current high pressure of the compressor is obtained. Low pressure at this moment Current return air temperature and the current ambient temperature Calculate the current high pressure Low pressure at this moment The current pressure difference And the current return air temperature and the current ambient temperature The current temperature difference Determine the current pressure difference Is it less than the set start pressure difference threshold ΔP? target , and the temperature difference at the current time Is it less than the set start temperature difference threshold? If yes, start the heating belt of the gas section of the compressor; In other cases, continue to obtain the next moment of high pressure Next moment low pressure Return air temperature at next moment and the ambient temperature at the next moment 2. The heat pump air conditioner capable of eliminating ice blockage in system circulation according to claim 1, characterized in that: The heating belt is arranged in the upper chamber of the gas division of the compressor and surrounds the upper chamber.

3. The heat pump air conditioner capable of eliminating ice blockage in system circulation according to claim 2, characterized in that: A filter is also arranged before the electronic expansion valve.

4. The heat pump air conditioner capable of eliminating ice blockage in system circulation according to claim 2, characterized in that: The starting pressure difference threshold ΔP target Set to 0.3MPa~0.5MPa.

5. The heat pump air conditioner capable of eliminating ice blockage in system circulation according to claim 2, characterized in that: The starting temperature difference threshold Set to 1℃~2℃.

6. The heat pump air conditioner capable of eliminating ice blockage in system circulation according to claim 2, characterized in that: The time interval between the next moment and the current moment is set to 25s to 35s.

7. The heat pump air conditioner capable of eliminating ice blockage in system circulation according to claim 2, characterized in that: The pressure difference satisfy: The temperature difference satisfy:

8. The heat pump air conditioner capable of eliminating ice blockage in system circulation according to claim 1, characterized in that: The first time period t1 is set to 18 minutes to 22 minutes.

9. The heat pump air conditioner capable of eliminating ice blockage in system circulation according to any one of claims 1 to 8, characterized in that: The controller also includes the control of the heating belt shutoff: Get the current return air temperature and the current ambient temperature Calculate the return air temperature at the current moment and the current ambient temperature The current temperature difference Determine the temperature difference at the current moment Is it greater than the set shutdown temperature difference threshold? If yes, turn off the heating belt of the gas section of the compressor; If not, continue to obtain the return air temperature at the next moment and the ambient temperature at the next moment 10. The heat pump air conditioner capable of eliminating ice blockage in system circulation according to claim 8, characterized in that: The shutdown temperature difference threshold Set to 4℃~5℃.

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