CN111426091A - Control device, air-conditioning heat pump system and control method thereof - Google Patents
Control device, air-conditioning heat pump system and control method thereof Download PDFInfo
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- CN111426091A CN111426091A CN202010214390.8A CN202010214390A CN111426091A CN 111426091 A CN111426091 A CN 111426091A CN 202010214390 A CN202010214390 A CN 202010214390A CN 111426091 A CN111426091 A CN 111426091A
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- 238000004378 air conditioning Methods 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 41
- 239000003507 refrigerant Substances 0.000 claims abstract description 57
- 238000010257 thawing Methods 0.000 claims abstract description 49
- 238000010438 heat treatment Methods 0.000 claims description 15
- 230000017525 heat dissipation Effects 0.000 claims description 5
- 238000005057 refrigeration Methods 0.000 claims description 3
- 230000000694 effects Effects 0.000 abstract description 11
- 238000002347 injection Methods 0.000 description 17
- 239000007924 injection Substances 0.000 description 17
- 238000001816 cooling Methods 0.000 description 8
- 239000007788 liquid Substances 0.000 description 8
- 238000004781 supercooling Methods 0.000 description 8
- 238000004891 communication Methods 0.000 description 6
- 230000002829 reductive effect Effects 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- 238000004590 computer program Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000006870 function Effects 0.000 description 4
- 239000000243 solution Substances 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 230000000203 accumulation affect Effects 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 230000000670 limiting effect Effects 0.000 description 1
- 230000036961 partial effect Effects 0.000 description 1
- 238000005192 partition Methods 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B13/00—Compression machines, plants or systems, with reversible cycle
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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
- F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
- F24F11/41—Defrosting; Preventing freezing
- F24F11/42—Defrosting; Preventing freezing of outdoor units
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B47/00—Arrangements for preventing or removing deposits or corrosion, not provided for in another subclass
- F25B47/02—Defrosting cycles
- F25B47/022—Defrosting cycles hot gas defrosting
- F25B47/025—Defrosting cycles hot gas defrosting by reversing the cycle
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2313/00—Compression machines, plants or systems with reversible cycle not otherwise provided for
- F25B2313/025—Compression machines, plants or systems with reversible cycle not otherwise provided for using multiple outdoor units
- F25B2313/0252—Compression machines, plants or systems with reversible cycle not otherwise provided for using multiple outdoor units with bypasses
- F25B2313/02522—Compression machines, plants or systems with reversible cycle not otherwise provided for using multiple outdoor units with bypasses during defrosting
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2600/00—Control issues
- F25B2600/25—Control of valves
- F25B2600/2513—Expansion valves
Abstract
The invention relates to a control device, an air-conditioning heat pump system and a control method thereof. Wherein, this air conditioner heat pump system includes at least one outdoor heat exchanger and at least one indoor heat exchanger through refrigerant pipe connection, the refrigerant pipe way includes: the indoor heat exchanger comprises a main path, a first electronic expansion valve, an indoor heat exchanger and a second electronic expansion valve, wherein the main path is provided with the first electronic expansion valve; the outdoor heat exchanger comprises a main circuit, a bypass branch circuit and a heat exchanger, wherein the main circuit is connected with the outdoor heat exchanger, the outdoor heat exchanger comprises a first part and a second part which are arranged up and down, the second part is arranged on the bypass branch circuit, the first side of the bypass branch circuit is connected to the main circuit, and the second side of the bypass branch circuit is connected to a gas collecting pipe of the outdoor heat exchanger; the bypass branch is provided with a valve at the position, close to the first side, of the second part, and the bypass branch is provided with a third electronic expansion valve at the position, close to the second side, of the second part. Through the arrangement, the defrosting effect of the air-conditioning heat pump system can be improved, and the performance of the whole machine can be improved.
Description
Technical Field
The invention relates to the technical field of air conditioning, in particular to a control device, an air conditioning heat pump system and a control method thereof.
Background
An air-conditioning heat pump system (e.g., an air-cooling type air-conditioning heat pump system) generally has a cooling mode and a heating mode, and air with a suitable temperature can be supplied to a room by circulating a refrigerant through a circuit formed by a compressor-an outdoor heat exchanger (generally referred to as a condenser) -a throttling part (e.g., an electronic expansion valve or a capillary tube, etc.) -an indoor heat exchanger (generally referred to as an evaporator) -a compressor. In case that the air conditioner is in the heating mode, the outdoor heat exchanger may be frosted. Specifically, when the evaporation temperature is lower than the dew point temperature corresponding to the outdoor environment temperature, the coil of the outdoor unit of the air conditioner begins to frost, and when the frost layer on the outer wall of the coil of the outdoor unit of the air conditioner is formed to a certain thickness, the heating capacity of the air conditioner is reduced to deteriorate. It is necessary to defrost the outdoor heat exchanger of the outdoor unit of the air conditioner in time.
For example, in the case of a commercial multi-split air conditioner in an air conditioning heat pump system, since the area of the outdoor heat exchanger is large, particularly for the bottom of the outdoor heat exchanger, condensed water may flow down, or defrosting water cannot be removed in time during defrosting, which may cause the bottom of the outdoor heat exchanger to be frozen, and if the multi-split air conditioner is operated for a long time under such a situation, the performance of the whole machine may be affected. Therefore, if the defrosting mechanism is uniformly performed on the whole outdoor heat exchanger, the problem that the performance of the whole outdoor heat exchanger is reduced due to incomplete defrosting at the bottom is solved.
To solve this problem, the following processing methods are generally adopted: the method is characterized in that a part of coil pipes at the bottom of the outdoor heat exchanger are used as subcoolers, and medium-temperature refrigerants flowing back from the indoor side firstly flow through the subcoolers at the bottom and then enter the evaporator through the electronic expansion valve and the liquid distributor, so that the problem of bottom frosting is avoided, namely the problem of bottom frosting is restrained by adopting a bottom subcooling treatment mode. However, because the supercooled pipe has the defect of large pressure loss, the treatment mode of bottom supercooling can avoid frosting and inevitably affect the performance of the whole machine
Accordingly, there is a need in the art for a new solution to the above problems.
Disclosure of Invention
Technical problem
In view of this, the present invention is directed to solve the problem of timely and effective defrosting of an outdoor heat exchanger of an air conditioning heat pump system.
Solution scheme
The invention provides an air-conditioning heat pump system, which comprises at least one outdoor heat exchanger and at least one indoor heat exchanger which are connected through a refrigerant pipeline, wherein the refrigerant pipeline comprises: the indoor heat exchanger is connected with the outdoor heat exchanger through the main path, a first electronic expansion valve is arranged on the main path, and a second electronic expansion valve is configured on the indoor heat exchanger; the outdoor heat exchanger comprises a first part and a second part which are arranged up and down, the second part is arranged on the bypass branch, the first side of the bypass branch is connected to the position, between the first electronic expansion valve and the second electronic expansion valve, of the main path, and the second side of the bypass branch is connected to a gas collecting pipe of the outdoor heat exchanger; the bypass branch is provided with a valve at the position, close to the first side, of the second part, and the bypass branch is provided with a third electronic expansion valve at the position, close to the second side, of the second part.
Through the mode of adding the bypass pipeline, in the process of defrosting the outdoor heat exchanger, the independent control about defrosting can be performed mainly aiming at the second part of the bottom, so that the bottom can have a more reliable defrosting effect, and finally, the defrosting of the outdoor heat exchanger is effectively realized. And compared with the mode of bottom supercooling treatment, the method can avoid pressure loss caused by the arrangement of the subcooler, thereby improving the overall performance of the air-conditioning heat pump system.
With regard to the air conditioning heat pump system described above, in one possible embodiment, the heat dissipation area of the first portion is larger than the heat exchange area of the second portion.
Through the arrangement, the total heat exchange area of the outdoor heat exchanger can be influenced as little as possible on the premise of targeted defrosting, so that the heat exchange performance of the outdoor heat exchanger is enhanced as much as possible on the premise of ensuring defrosting reliability.
For example, in order to ensure an effective heat exchange area of the outdoor heat exchanger, the heat exchange area of the first portion should be substantially larger than that of the second portion. As an example, the second portion of the bottom includes 2-3 rows of coils.
The second aspect of the present invention provides a control method for an air-conditioning heat pump system, the control method comprising: acquiring an operation mode of the air-conditioning heat pump system; selectively opening the valve and adjusting the opening degree of the third electronic expansion valve according to the operation mode; wherein, the air-conditioning heat pump system is any one of the air-conditioning heat pump systems.
With this arrangement, the function of the second portion of the outdoor heat exchanger can be adjusted and switched so as to adjust the refrigerant in the second portion of the bottom portion, thereby achieving better performance of the outdoor heat exchanger.
With regard to the control method of the air conditioning heat pump system, in a possible implementation, the "selectively opening the valve and adjusting the opening degree of the third electronic expansion valve according to the operation mode" specifically includes: and when the operation mode is a heating mode, closing the valve and the third electronic expansion valve.
With such an arrangement, the occurrence of the frosting phenomenon can be suppressed by blocking the cooling capacity.
With regard to the control method of the air conditioning heat pump system described above, in one possible embodiment, after the step of "closing the valve and the third electronic expansion valve", the control method further includes: detecting a temperature of the second portion; and when the temperature of the second part is lower than a first set value, opening the valve and adjusting the opening degree of the third electronic expansion valve so as to enable the medium-temperature refrigerant from the main path to flow into the second part.
By such an arrangement, the occurrence of the frosting phenomenon can be suppressed more effectively.
In one possible embodiment, the method for controlling the air-conditioning heat pump system includes: and enabling the medium-temperature refrigerant from the main path to flow into the second part, and closing the third electronic expansion valve and the valve after the temperature of the second part rises to a second set value.
It is to be understood that the second set value should be greater than the first set value, and by such an arrangement, injection control for causing the middle temperature refrigerant to be briefly injected in the bypass branch, such as an injection time and an opening degree of the third expansion valve during injection, may be determined according to the detected temperature of the second portion. In addition, the second set value may be a fixed value or may be corrected according to the external environment temperature
In one possible embodiment, the method for controlling the air-conditioning heat pump system includes: flowing a medium temperature refrigerant from the main path into the second portion; judging whether a state of causing the medium-temperature refrigerant from the main path to flow into the second part satisfies a cut-off condition; if so, closing the third electronic expansion valve and the valve regardless of whether the temperature of the second portion rises to a second set value.
It should be noted that, because the short-term injection of the medium-temperature refrigerant in the bypass branch is an emergency means, the long injection time may affect the performance of the whole air-conditioning heat pump system, specifically, the injection process itself is an unloading process, which may cause the problem of air suction and liquid entrainment, and the refrigerant may have a certain effect of inhibiting frosting due to the non-circulation of the refrigerant itself, so that a cut-off condition capable of forcibly stopping the short-term injection may be set, for example, a time upper limit may be set, or the duration of the short-term injection may be limited according to the degree of superheat of the air suction. Taking the setting of an upper time limit as an example, a person skilled in the art can determine the target use environment of the product by means of experiments, analysis, and the like according to a specific product.
In the case where the injection is forcibly turned off based on the restriction on the continuity of the brief injection, if there is a possibility of frosting because the temperature has not yet reached the second set value, the problem will be solved in the defrosting mode, that is, the heat pump system of the present invention can maximally suppress the frosting phenomenon of the second portion of the bottom portion in the heating mode even in the defrosting mode.
With such an arrangement, the occurrence of the frosting phenomenon is suppressed more effectively, and the influence on the performance of the air-conditioning heat pump system is reduced as little as possible.
With regard to the control method of the air-conditioning heat pump system described above, in one possible embodiment, "selectively opening the valve and adjusting the opening degree of the third electronic expansion valve according to the operation mode" specifically includes: when the operation mode is the defrosting mode, opening the valve and adjusting the opening degree of the third electronic expansion valve according to the following modes: detecting a temperature of the second portion; and adjusting the opening degree of the third electronic expansion valve according to the temperature of the second part to ensure that the second part of the outdoor heat exchanger reaches a set defrosting target.
By such arrangement, the defrosting capacity of the second part is enhanced by independently controlling the temperatures of the second part on the basis of ensuring that normal defrosting is continuously realized through the first part of the top part, so as to thoroughly suppress the occurrence of the frosting phenomenon. The defrost target as set may be: the temperature of the second part is maintained at a set level without frosting by detecting the temperature of the second part and adjusting the third electronic expansion valve, so that the defrosting is ensured to be clean and the flowing defrosting water is not frozen. The set level can be determined experimentally, analytically, etc. for a particular product. Furthermore, the actual presentation of the set defrosting target may be determined by those skilled in the art in other reasonable ways, as long as the criterion is ensured to avoid that the performance of the air-conditioning heat pump system is affected by frosting.
The bypass branch is additionally arranged between the refrigerant pipeline in front of the second electronic expansion valve of the outdoor unit of the air conditioner and the gas collecting pipe of the outdoor heat exchanger of the outdoor unit of the air conditioner, and the bypass branch passes through the second part of the bottom of the outdoor heat exchanger. And in the defrosting mode, the four-way valve reversing complete machine defrosts in a reverse circulation mode, and on the basis, the third electronic expansion valve and the valve are independently controlled aiming at the second part at the bottom, and the defrosting level of the first part at the top is different from that of the first part at the top, so that the defrosting is more effective. Therefore, the defrosting level of the outdoor heat exchanger is ensured on the basis of carrying out non-uniform treatment on the first part and the second part.
With regard to the control method of the air-conditioning heat pump system described above, in one possible embodiment, "selectively opening the valve and adjusting the opening degree of the third electronic expansion valve according to the operation mode" specifically includes: when the operation mode is a refrigeration mode, opening the valve and adjusting the opening degree of the third electronic expansion valve according to the following modes: detecting a temperature of the second portion; and adjusting the opening degree of the third electronic expansion valve according to the temperature of the second part to ensure that the temperature of the refrigerant flowing out of the second part of the outdoor heat exchanger is approximately the same as that of the refrigerant flowing out of the first part.
Through the arrangement, under the condition that the frosting phenomenon can not occur, the heat exchange capacity of the second part customized for defrosting inhibition is returned to the outdoor heat exchanger, so that better overall performance can be achieved.
A third aspect of the present invention provides a control apparatus including a memory storing a program capable of executing the steps of the method for controlling an air-conditioning heat pump system according to any one of the preceding claims, and a processor capable of calling the program and executing the steps of the method according to any one of the preceding claims.
The control device has all the technical effects of the control method of the air-conditioning heat pump system, and the details are not repeated herein.
It can be seen that the present invention makes the following steps by planning the outdoor heat exchanger: in the heating mode, the second part does not circulate the refrigerant as much as possible, and the frosting phenomenon of the second part is effectively inhibited. In the defrosting mode, the defrosting control of the second part at the bottom of the outdoor heat exchanger is enhanced by adjusting the third electronic expansion valve, so that the phenomenon that the bottom of the outdoor heat exchanger is not completely defrosted is effectively prevented while the whole heat exchanger is defrosted, and the phenomenon that the whole capacity of the air-conditioning heat pump system is influenced after the bottom is not completely defrosted and continuously freezes is also effectively avoided. And the second part is reduced to have the same function as the first part at the top in the refrigeration mode, so that the heat exchange area of the outdoor heat exchanger is ensured. Compared with the mode of arranging the coil pipe at the bottom into the supercooling pipe, the invention not only can return the heat exchange area of the outdoor heat exchanger occupied by the supercooling at the bottom, but also completely avoids the pressure loss caused by the arrangement of the supercooling pipe and is beneficial to the improvement of the overall performance of the air-conditioning heat pump system.
Drawings
Embodiments of the present invention will be described below with reference to the accompanying drawings in which:
FIG. 1 is a schematic diagram of a multi-split air conditioner according to an embodiment of the present invention;
fig. 2 is a flowchart illustrating a control method of a multi-split air conditioner according to an embodiment of the invention;
fig. 3 is a schematic view illustrating a flow direction of a refrigerant in a heating mode of a multi-split air conditioner according to an embodiment of the present invention;
fig. 4 is a schematic diagram illustrating a refrigerant flow direction of the multi-split air conditioner in the defrosting mode according to an embodiment of the invention; and
fig. 5 is a schematic view illustrating a flow direction of refrigerant in a cooling mode of a multi-split air conditioner according to an embodiment of the present invention.
List of reference numerals:
1. an outdoor heat exchanger; 11. a first portion; 12. a second portion; 2. an indoor heat exchanger; 3. a compressor; 4. a four-way valve; 5. a gas-liquid separator; 6. a main road; 71. a first electronic expansion valve; 72. a second electronic expansion valve; 73. a third electronic expansion valve; 74. an electromagnetic valve; 8. a bypass branch.
Detailed Description
For the purpose of facilitating understanding of the present invention, the present invention will be described more fully and in detail below with reference to the accompanying drawings and examples, but it will be understood by those skilled in the art that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of the present invention. Although the present embodiment is described with respect to a multi-split air conditioner including one outdoor unit and a plurality of indoor units, it is obvious that the multi-split air conditioner may be in other forms, such as a plurality of outdoor units.
In the description of the present invention, a "module" or "processor" may include hardware, software, or a combination of both. A module may comprise hardware circuitry, various suitable sensors, communication ports, memory, may comprise software components such as program code, or may be a combination of software and hardware. The processor may be a central processing unit, microprocessor, image processor, digital signal processor, or any other suitable processor. The processor has data and/or signal processing functionality. The processor may be implemented in software, hardware, or a combination thereof. Non-transitory computer readable storage media include any suitable medium that can store program code, such as magnetic disks, hard disks, optical disks, flash memory, read-only memory, random-access memory, and the like. The term "a and/or B" denotes all possible combinations of a and B, such as a alone, B alone or a and B. The term "at least one A or B" or "at least one of A and B" means similar to "A and/or B" and may include only A, only B, or both A and B. The singular forms "a", "an" and "the" may include the plural forms as well.
It should be noted that in the description of the present invention, the terms of direction or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, which are merely for convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
The air conditioner generally includes an outdoor unit and an indoor unit, the outdoor unit is mainly provided with a compressor, an outdoor fan and an outdoor heat exchanger (generally called condenser), the indoor unit is mainly provided with an indoor heat exchanger (generally called evaporator), and the compressor, the condenser, the evaporator and the compressor form a refrigerant circulation loop. When the refrigerant circulates along the compressor → the outdoor heat exchanger → the indoor heat exchanger → the compressor, the air conditioner is in a refrigerating cycle. When the refrigerant circulates along the compressor → the indoor heat exchanger → the outdoor heat exchanger → the compressor, the air conditioner is in a heating cycle. In the case where the air conditioner is in a heating cycle, there is a possibility that the outdoor heat exchanger is frosted. If defrosting/defrosting is not performed in time, the heating performance of the air conditioner is affected.
Compared with the traditional air conditioner, on one hand, the outdoor unit of the multi-split air conditioner has the characteristic of large area of the outdoor heat exchanger, and on the other hand, once the outdoor heat exchanger of the outdoor unit of the multi-split air conditioner is not subjected to timely and effective defrosting operation, the performance of the indoor units of the multi-split air conditioner can be influenced. Based on the premise, the inventor analyzes the outdoor heat exchanger of the multi-split air conditioner in the following way: when the outdoor heat exchanger is defrosted, if defrosting water cannot be discharged at the bottom in time, the defrosting water is easy to freeze to cause incomplete defrosting at the bottom, and frost layer accumulation affects the heat exchange effect of the outdoor unit of the air conditioner after long-time operation, so that the performance of the whole machine is reduced.
The prior art, recognizing this phenomenon, typically makes such improvements to the coil at the bottom of the outdoor heat exchanger: the coil pipe at the bottom is used as a supercooling pipe. Thus, the middle temperature refrigerant flowing through the supercooling pipe can make the bottom not frosted, but is limited by the size of the outdoor heat exchanger, the flow area of the supercooling pipe is quite limited, and a large pressure loss is generally caused, which causes the problem that: in order to prevent the arrangement of frosting from generating adverse effect which influences the performance of the whole machine. Obviously, this is a problem of overall performance that arises in the process of solving an overall performance problem, and the solved problem and the newly arising problem are not very different.
Based on such a situation, the present invention has been made in consideration of the difference between the regions to which defrosting is applied, and particularly, needs to be intensively improved with respect to the bottom region of the outdoor heat exchanger.
Referring to fig. 1, fig. 1 is a schematic structural diagram of a multi-split air conditioner according to an embodiment of the invention. As shown in fig. 1, the multi-split air conditioner includes an outdoor unit 1 and a plurality of indoor units 2, wherein the outdoor heat exchanger is divided into a first portion (as a main heat exchanger) 11 at the top and a second portion (as a bypass heat exchanger) 12 at the bottom, it is understood that the division is not strictly, such as: the outer shell is divided into two cavities by a partition plate, and the first part and the second part are respectively arranged in the two cavities. But mainly aims at the division of pipeline communication, namely the corresponding communication targets of the liquid inlet side and the liquid outlet side of the first part and the second part are different. In other words, in the present invention, the division of the outdoor heat exchanger into the first part and the second part should be understood as selectively dividing the two regions at the visual level on the basis of the definition of the corresponding communication targets of the liquid inlet side and the liquid outlet side of the first part and the second part. Therefore, in the process of defrosting the outdoor heat exchanger, the defrosting effect of the second part at the bottom of the outdoor heat exchanger is enhanced. Specifically, the bypass branch is configured for the second part, and when in the heating mode, the second part does not flow the refrigerant, so that the frosting phenomenon is inhibited. In the defrosting mode, the defrosting effect is enhanced by the independently controlled refrigerant in the bypass branch. In the two modes, the heat exchange area of the outdoor heat exchanger is mainly converted into the heat dissipation area of the first part, so that in order to ensure the heat exchange performance of the outdoor heat exchanger, the heat dissipation area of the first part should be obviously larger than that of the second part, for example, 2-3 rows of coils at the bottommost part of the outdoor heat exchanger are usually used as the second part.
Specifically, the multi-split air conditioner further comprises an outdoor heat exchanger 1, a plurality of indoor heat exchangers 2, a compressor 3, a four-way valve 4 and a gas-liquid separator 5 which are connected through a refrigerant pipeline, the plurality of indoor heat exchangers are connected with the outdoor heat exchanger through a main pipeline 6 after being gathered, a first electronic expansion valve 71 is arranged on the main pipeline 6, each indoor heat exchanger is provided with a second electronic expansion valve 72, each outdoor heat exchanger comprises a first portion 11 and a second portion 12, each second portion is provided with a bypass branch 8, a first side (the left side in the figure 1) of each bypass branch is connected to a position, located between the corresponding first and second expansion valves, of the refrigerant pipeline, a second side (the right side in the figure 1) of each bypass branch is connected to a gas collecting pipe of the corresponding outdoor heat exchanger, namely, the refrigerant pipeline is. The bypass branch is provided with a third electronic expansion valve 73 at a position near the second side of the second portion, and a valve, such as a solenoid valve 74, is provided at a position near the first side of the second portion.
Referring to fig. 2, fig. 2 is a flowchart illustrating a control method of a multi-split air conditioner according to an embodiment of the present invention. As shown in fig. 2, based on the above structure, the control method of the multi-split air conditioner of the present invention mainly includes the following steps:
s1, acquiring the operation mode of the multi-split air conditioner;
and S2, selectively opening the electromagnetic valve and adjusting the opening degree of the third electronic expansion valve according to the operation mode.
Referring to fig. 2 and 3, fig. 3 is a schematic view illustrating a flow direction of a refrigerant in a heating mode of a multi-split air conditioner according to an embodiment of the present invention. As shown in fig. 2 and 3, when any air conditioning indoor unit is in the heating mode, S2 specifically includes: and closing the electromagnetic valve and the third electronic expansion valve, wherein the bypass branch does not allow the refrigerant to pass through. That is, no refrigerant passes through the second portion corresponding to the bypass branch. Thus, even if the outdoor environment temperature meets the frosting condition, the arrangement can greatly inhibit the frosting phenomenon at the bottom of the outdoor heat exchanger.
At this time, it is assumed that the temperature sensor detects that the temperature of the second portion is still lower than the preset value, and in particular, there is still a possibility of frosting in the case of being lower than the preset value. For this case, S2 is modified as follows:
detecting a temperature of a second portion after closing the solenoid valve and the third electronic expansion valve;
and under the condition that the temperature of the second part is less than the first set value, opening the electromagnetic valve and adjusting the opening degree of the third electronic expansion valve so as to enable the medium-temperature refrigerant from the main path to flow into the second part. Specifically, the solenoid valve is opened and the third electronic expansion valve is adjusted as follows: the refrigerant is injected in the second portion corresponding to the bypass branch only for a short time, and since the middle temperature refrigerant passes through the second portion during the injection, the temperature of the second portion can be adjusted, for example, raised to a second set value higher than the first set value, which can be flexibly determined according to actual conditions, although it can be understood that the second portion is prevented from frosting when the second set value is ensured.
However, since the short injection of the medium temperature refrigerant in the bypass branch is an emergency measure, the long injection time may affect the performance of the whole air conditioning heat pump system, and thus, for example, the following may be set: the brief injection is forcibly stopped in case the injection time reaches an upper time limit.
Referring to fig. 2 and 4, fig. 4 is a schematic diagram illustrating a refrigerant flow direction of the multi-split air conditioner in the defrosting mode according to an embodiment of the present invention. As shown in fig. 2 and 4, when any air conditioning indoor unit is in the defrosting mode, S2 specifically includes: opening the solenoid valve and adjusting the third electronic expansion valve as follows: and the opening degree of the third electronic expansion valve is independently adjusted according to the temperature of the second part so as to enhance the defrosting effect of the second part at the bottom of the outdoor heat exchanger. During this period, the refrigerant temperature in the second portion adjusted by the opening degree of the third electronic expansion valve is mainly for enhancing the defrosting requirement of the second portion, and therefore, the control mechanisms of the refrigerant temperature in the first portion and the refrigerant temperature in the second portion are different.
Referring to fig. 2 and 5, fig. 5 is a schematic view illustrating a flow direction of a refrigerant in a cooling mode of a multi-split air conditioner according to an embodiment of the present invention. As shown in fig. 2 and 5, when any air conditioning indoor unit is in the cooling mode, S2 specifically includes: since there is no concern about the second partial frost formation in this mode, the solenoid valve may be opened and the third electronic expansion valve adjusted as follows: and adjusting the opening degree of the third electronic expansion valve according to the temperature of the second part to ensure that the temperature of the refrigerant flowing out of the second part of the outdoor heat exchanger is approximately the same as that of the refrigerant flowing out of the first part. That is, in this case, the refrigerant functions in the second portion and the first portion are substantially the same, and all areas of the outdoor heat exchanger can be effectively used. That is to say, under the condition that the risk of frosting does not exist, the second part can be converted into the first part, and at the moment, the heat exchanger is reduced into the outdoor heat exchanger which participates in heat exchange in the whole area in the traditional sense, so that the air processing capacity of the multi-split air conditioner is ensured. Therefore, although the control manner of opening the solenoid valve and adjusting the opening degree of the third electronic expansion valve is performed in both the defrosting mode and the cooling mode, the temperature node corresponding to the adjusted opening degree has a significant difference.
As in a specific embodiment, during defrosting, the bypass branch is in a communication state, and in order to ensure defrosting effect, the opening degrees of the solenoid valve and the third electronic expansion valve may be adjusted according to the temperature of the second portion detected by the temperature sensor, for example, the temperature of the second portion may be maintained at a certain temperature value above 0 ℃ to prevent the frost water from freezing at the bottom. During heating, the bypass branch circuit is mainly in a non-communication state, namely the solenoid valve and the third expansion solenoid valve are in a closed state. If a short injection is required, the solenoid valve can be set at a lower fixed opening, and the injection can be terminated when the temperature of the second part rises back to the second set value. During the cooling period, because the possibility of frost formation is not considered, the adjustment of the bypass branch can be performed based on the temperature comparison of the first part and the second part of the outdoor heat exchanger, for example, the opening degree of the electromagnetic valve can be set to a certain fixed opening degree, so as to ensure the uniform distribution of each branch refrigerant in the whole heat exchanger.
It should be noted that, although the foregoing embodiments describe each step in a specific sequence, those skilled in the art will understand that, in order to achieve the effect of the present invention, different steps do not necessarily need to be executed in such a sequence, and they may be executed simultaneously (in parallel) or in other sequences, and these changes are all within the protection scope of the present invention.
In a control device of the present invention, processing functions of the respective steps of the aforementioned method are included. In one embodiment, the control device at least comprises a processor and a memory, wherein the memory stores a program capable of executing the control method of the multi-split air conditioner, and the processor calls the corresponding program in the memory and executes the corresponding steps of the method according to different operation modes.
It will be understood by those skilled in the art that all or part of the flow of the method according to the above-described embodiment may be implemented by a computer program, which may be stored in a computer-readable storage medium and used to implement the steps of the above-described embodiments of the method when the computer program is executed by a processor. Wherein the computer program comprises computer program code, which may be in the form of source code, object code, an executable file or some intermediate form, etc. The computer-readable medium may include: any entity or device capable of carrying said computer program code, media, usb disk, removable hard disk, magnetic diskette, optical disk, computer memory, read-only memory, random access memory, electrical carrier wave signals, telecommunication signals, software distribution media, etc. It should be noted that the computer readable medium may contain content that is subject to appropriate increase or decrease as required by legislation and patent practice in jurisdictions, for example, in some jurisdictions, computer readable media does not include electrical carrier signals and telecommunications signals as is required by legislation and patent practice.
So far, the technical solution of the present invention has been described with reference to one embodiment shown in the drawings, but it is easily understood by those skilled in the art that the scope of the present invention is obviously not limited to these specific embodiments. Equivalent changes or substitutions of related technical features can be made by those skilled in the art without departing from the principle of the invention, and the technical scheme after the changes or substitutions can fall into the protection scope of the invention.
Claims (10)
1. An air conditioner heat pump system, characterized in that, air conditioner heat pump system includes at least one outdoor heat exchanger and at least one indoor heat exchanger through refrigerant pipe connection, the refrigerant pipe way includes:
the indoor heat exchanger is connected with the outdoor heat exchanger through the main path, a first electronic expansion valve is arranged on the main path, and a second electronic expansion valve is configured on the indoor heat exchanger; and
the outdoor heat exchanger comprises a bypass branch, a main branch and a bypass branch, wherein the bypass branch comprises a first part and a second part which are arranged up and down, the second part is arranged on the bypass branch, the first side of the bypass branch is connected to the position, between the first electronic expansion valve and the second electronic expansion valve, of the main branch, and the second side of the bypass branch is connected to a gas collecting pipe of the outdoor heat exchanger;
the bypass branch is provided with a valve at the position, close to the first side, of the second part, and the bypass branch is provided with a third electronic expansion valve at the position, close to the second side, of the second part.
2. An air conditioning heat pump system according to claim 1, wherein the heat dissipation area of the first portion is larger than the heat dissipation area of the second portion.
3. A control method of an air conditioner heat pump system is characterized by comprising the following steps:
acquiring an operation mode of the air-conditioning heat pump system;
selectively opening the valve and adjusting the opening degree of the third electronic expansion valve according to the operation mode;
wherein the air-conditioning heat pump system is the air-conditioning heat pump system of claim 1 or 2.
4. A control method for an air conditioning heat pump system according to claim 3, wherein the "selectively opening the valve and adjusting the opening degree of the third electronic expansion valve according to the operation mode" specifically includes:
and when the operation mode is a heating mode, closing the valve and the third electronic expansion valve.
5. A control method of an air conditioning heat pump system according to claim 4, wherein after the step of "closing the valve and the third electronic expansion valve", the control method further comprises:
detecting a temperature of the second portion;
and when the temperature of the second part is lower than a first set value, opening the valve and adjusting the opening degree of the third electronic expansion valve so as to enable the medium-temperature refrigerant from the main path to flow into the second part.
6. A control method for an air conditioning heat pump system according to claim 5, wherein opening the valve and adjusting the opening degree of the third electronic expansion valve so that the medium temperature refrigerant from the main path flows into the second portion specifically comprises:
and enabling the medium-temperature refrigerant from the main path to flow into the second part, and closing the third electronic expansion valve and the valve after the temperature of the second part rises to a second set value.
7. A control method for an air conditioning heat pump system according to claim 5, wherein opening the valve and adjusting the opening degree of the third electronic expansion valve so that the medium temperature refrigerant from the main path flows into the second portion specifically comprises:
flowing a medium temperature refrigerant from the main path into the second portion;
judging whether a state of causing the medium-temperature refrigerant from the main path to flow into the second part satisfies a cut-off condition;
if so, closing the third electronic expansion valve and the valve regardless of whether the temperature of the second portion rises to a second set value.
8. The method for controlling the air-conditioning heat pump system according to any one of claims 3 to 7, wherein "selectively opening the valve and adjusting the opening degree of the third electronic expansion valve according to the operation mode" specifically includes:
when the operation mode is the defrosting mode, opening the valve and adjusting the opening degree of the third electronic expansion valve according to the following modes:
detecting a temperature of the second portion;
and adjusting the opening degree of the third electronic expansion valve according to the temperature of the second part to ensure that the second part of the outdoor heat exchanger reaches a set defrosting target.
9. The method for controlling the air-conditioning heat pump system according to any one of claims 3 to 7, wherein "selectively opening the valve and adjusting the opening degree of the third electronic expansion valve according to the operation mode" specifically includes:
when the operation mode is a refrigeration mode, opening the valve and adjusting the opening degree of the third electronic expansion valve according to the following modes:
detecting a temperature of the second portion;
and adjusting the opening degree of the third electronic expansion valve according to the temperature of the second part to ensure that the temperature of the refrigerant flowing out of the second part of the outdoor heat exchanger is approximately the same as that of the refrigerant flowing out of the first part.
10. A control apparatus characterized by comprising a memory storing a program capable of executing the steps of the control method of the air-conditioning heat pump system according to any one of claims 3 to 9, and a processor capable of calling the program and executing the steps of the method according to any one of claims 3 to 9.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114198865A (en) * | 2021-11-19 | 2022-03-18 | 青岛海尔空调电子有限公司 | Air conditioning unit and control method thereof |
| CN114838529A (en) * | 2021-09-19 | 2022-08-02 | 青岛海尔空调器有限总公司 | Method and device for adjusting heat exchange volume of heat exchanger and air conditioner |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201535589U (en) * | 2009-10-20 | 2010-07-28 | 广东美的电器股份有限公司 | Heat pump air-conditioning system |
| CN102721149A (en) * | 2012-05-08 | 2012-10-10 | 广东美的制冷设备有限公司 | Air conditioner and control method thereof |
| CN103782115A (en) * | 2011-09-12 | 2014-05-07 | 大金工业株式会社 | Refrigeration device |
| CN105627432A (en) * | 2015-12-25 | 2016-06-01 | 珠海格力电器股份有限公司 | Air conditioning system and defrosting control method thereof |
| CN106440462A (en) * | 2016-11-22 | 2017-02-22 | 珠海格力电器股份有限公司 | Air conditioning unit and control method for same |
| CN110686362A (en) * | 2019-10-28 | 2020-01-14 | 宁波奥克斯电气股份有限公司 | Operation control method and system of air conditioner, air conditioner and storage medium |
-
2020
- 2020-03-24 CN CN202010214390.8A patent/CN111426091A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201535589U (en) * | 2009-10-20 | 2010-07-28 | 广东美的电器股份有限公司 | Heat pump air-conditioning system |
| CN103782115A (en) * | 2011-09-12 | 2014-05-07 | 大金工业株式会社 | Refrigeration device |
| CN102721149A (en) * | 2012-05-08 | 2012-10-10 | 广东美的制冷设备有限公司 | Air conditioner and control method thereof |
| CN105627432A (en) * | 2015-12-25 | 2016-06-01 | 珠海格力电器股份有限公司 | Air conditioning system and defrosting control method thereof |
| CN106440462A (en) * | 2016-11-22 | 2017-02-22 | 珠海格力电器股份有限公司 | Air conditioning unit and control method for same |
| CN110686362A (en) * | 2019-10-28 | 2020-01-14 | 宁波奥克斯电气股份有限公司 | Operation control method and system of air conditioner, air conditioner and storage medium |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114838529A (en) * | 2021-09-19 | 2022-08-02 | 青岛海尔空调器有限总公司 | Method and device for adjusting heat exchange volume of heat exchanger and air conditioner |
| CN114198865A (en) * | 2021-11-19 | 2022-03-18 | 青岛海尔空调电子有限公司 | Air conditioning unit and control method thereof |
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Application publication date: 20200717 |