CN106524338B - Multi-line system and its supercooling circuit valve body control method - Google Patents
Multi-line system and its supercooling circuit valve body control method Download PDFInfo
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- CN106524338B CN106524338B CN201611076285.2A CN201611076285A CN106524338B CN 106524338 B CN106524338 B CN 106524338B CN 201611076285 A CN201611076285 A CN 201611076285A CN 106524338 B CN106524338 B CN 106524338B
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- valve body
- supercooling
- cold loop
- circuit valve
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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
- F24F3/00—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems
- F24F3/06—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the arrangements for the supply of heat-exchange fluid for the subsequent treatment of primary air in the room units
- F24F3/065—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the arrangements for the supply of heat-exchange fluid for the subsequent treatment of primary air in the room units with a plurality of evaporators or condensers
-
- 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
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/62—Control or safety arrangements characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/70—Control systems characterised by their outputs; Constructional details thereof
- F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
- F24F11/83—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/62—Control or safety arrangements characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
- F24F11/63—Electronic processing
- F24F11/64—Electronic processing using pre-stored data
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/70—Control systems characterised by their outputs; Constructional details thereof
- F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
- F24F11/83—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers
- F24F11/84—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers using valves
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fuzzy Systems (AREA)
- Mathematical Physics (AREA)
- Signal Processing (AREA)
- Air Conditioning Control Device (AREA)
Abstract
The invention discloses a kind of multi-line system and its supercooling circuit valve body control method, it the described method comprises the following steps: when multi-line system is run with pure refrigeration mode or main refrigeration mode, judging whether the degree of supercooling of the inlet of cold loop is less than preset minimum subcooled temperature；If it is less, the target superheat degree of maximum allowable aperture and the exit for crossing cold loop to supercooling circuit valve body is modified；PI control is carried out to supercooling circuit valve body according to the target superheat degree of the maximum allowable aperture of revised supercooling circuit valve body and the exit for crossing cold loop.It is modified by the maximum opening to supercooling circuit valve body and the outlet superheat degree for crossing cold loop, to prevent from causing cold loop to become flat because valve body aperture is bigger than normal, cause system without degree of supercooling, the problem of indoor unit effect of freezing is deteriorated, so that system can obtain preferable refrigeration effect, and efficiency with higher.
Description
Technical field
The present invention relates to air-conditioning technical field, in particular to the control method of circuit valve body is subcooled in a kind of multi-line system
And a kind of multi-line system.
Background technique
Multi-line system have it is pure refrigeration, it is pure heating, it is main refrigeration and four kinds of modes of main heating, wherein main refrigeration mode with
Main heating mode can utilize the condensation heat and heat of evaporation of system simultaneously, substantially increase the efficiency of system.Usual multi-connected machine system
System is made of outdoor unit, indoor unit and part flow arrangement three parts, and liquid state refrigerant is assigned to tool by part flow arrangement by outdoor unit
In the indoor unit for there are different cooling and warming demands, cold loop was provided in part flow arrangement, and worked as with two concatenated heat exchangers
Make aftercooler.
In view of the versatility of part flow arrangement, part flow arrangement is typically designed to meet very big limit of power, i.e. room
Outer machine all uses the same part flow arrangement from very little ability (such as 6ton) to very big ability (such as 30ton), at this point, in part flow arrangement
The type selecting of related valve body usually consider the service condition under most adverse circumstances, i.e., consideration outdoor unit ability is maximum and cold medium flux
Maximum situation.But when outdoor unit ability is smaller, related valve body just seems bigger than normal.For example, working as outdoor temperature and Indoor Temperature
It spends in all higher situation and freezes or outdoor heat exchanger is there are dirty stifled etc., the supercooling of part flow arrangement is entered from outdoor unit
It spends very low (even without degree of supercooling), crossing cold loop will appear deflation, and system can control valve body according to the degree of superheat at this time,
The opening valve body to maximum of mistake, causes to become flat more serious, and system is deteriorated without supercooling effect, refrigeration indoor unit effect.
Summary of the invention
The present invention is directed to solve at least some of the technical problems in related technologies.
For this purpose, an object of the present invention is to provide the control method that circuit valve body is subcooled in a kind of multi-line system,
It is modified by the maximum opening to supercooling circuit valve body and the outlet superheat degree for crossing cold loop, to prevent because valve body aperture is inclined
It is big and cold loop was caused to become flat, lead to system without degree of supercooling, the problem of indoor unit effect of freezing is deteriorated, so that being
System can obtain preferable refrigeration effect, and efficiency with higher.
It is another object of the present invention to propose a kind of multi-line system.
To achieve the above object, one aspect of the present invention embodiment, which proposes, is subcooled circuit valve body in a kind of multi-line system
Control method, the multi-line system include outdoor unit, multiple indoor units and part flow arrangement, and the part flow arrangement includes being subcooled back
Road, the supercooling circuit valve body are arranged in the inlet for crossing cold loop, the described method comprises the following steps: when described multi-joint
When machine system is run with pure refrigeration mode or main refrigeration mode, judge whether the degree of supercooling of the inlet for crossing cold loop is small
In preset minimum subcooled temperature；If the degree of supercooling of the inlet for crossing cold loop is less than the preset minimum subcooled temperature,
Then the maximum allowable aperture to the supercooling circuit valve body and the target superheat degree in the exit for crossing cold loop are modified；
And according to the maximum allowable aperture of the revised supercooling circuit valve body and the target mistake in the exit for crossing cold loop
Temperature carries out PI control to the supercooling circuit valve body.
The control method of circuit valve body is subcooled in multi-line system according to an embodiment of the present invention, when multi-line system is with pure
When refrigeration mode or main refrigeration mode are run, if the degree of supercooling for crossing the inlet of cold loop is less than preset minimum supercooling
Degree, then the maximum allowable aperture to supercooling circuit valve body and the target superheat degree in the exit for crossing cold loop are modified, and root
According to the maximum allowable aperture of revised supercooling circuit valve body and the target superheat degree in the exit of cold loop excessively to cold loop excessively
Valve body carries out PI control.To be repaired by the maximum opening to supercooling circuit valve body with the outlet superheat degree for crossing cold loop
Just, it prevents from causing cold loop to become flat because valve body aperture is bigger than normal, causes system without degree of supercooling, indoor unit effect of freezing
The problem of variation, so that system can obtain preferable refrigeration effect, and efficiency with higher.
According to one embodiment of present invention, the current maximum allowable aperture of the supercooling circuit valve body is reduced first in advance
If value, to obtain the maximum allowable aperture of the revised supercooling circuit valve body.
According to one embodiment of present invention, the current goal degree of superheat in the exit for crossing cold loop is increased by second
Preset value, to obtain the target superheat degree in the revised exit for crossing cold loop.
According to one embodiment of present invention, judging it is default whether the degree of supercooling of the inlet for crossing cold loop is less than
Minimum subcooled temperature before, further includes: judge whether the aperture of the supercooling circuit valve body is greater than the first default aperture, and judge
Whether the time for carrying out PI adjusting to the supercooling circuit valve body is greater than the first preset time；If the supercooling circuit valve body
Aperture is greater than the described first default aperture, or the time for carrying out PI adjusting to the supercooling circuit valve body is greater than described first in advance
If the time, then further judge whether the degree of supercooling of the inlet for crossing cold loop is less than the preset minimum supercooling
Degree.
According to one embodiment of present invention, according to it is revised it is described supercooling circuit valve body maximum allowable aperture and
After the target superheat degree in the exit for crossing cold loop carries out PI control to the supercooling circuit valve body, further includes: judge institute
Whether the degree of supercooling for stating the inlet of cold loop is more than or equal to the preset minimum subcooled temperature；If the cold loop excessively
The degree of supercooling of inlet is more than or equal to the preset minimum subcooled temperature, then stops to the maximum allowable of the supercooling circuit valve body
Aperture and the target superheat degree in the exit for crossing cold loop are modified；Otherwise, continue to the supercooling circuit valve body
Maximum allowable aperture and the target superheat degree in the exit for crossing cold loop are modified.
To achieve the above object, another aspect of the present invention embodiment proposes a kind of multi-line system, comprising: outdoor unit；
Multiple indoor units；Part flow arrangement, the part flow arrangement included cold loop, and the supercooling circuit valve body setting is subcooled back described
The inlet on road；Control module, the control module are used for when the multi-line system is with pure refrigeration mode or main refrigeration mould
When formula is run, judge whether the degree of supercooling of the inlet for crossing cold loop is less than preset minimum subcooled temperature, wherein if institute
The degree of supercooling for stating the inlet of cold loop is less than the preset minimum subcooled temperature, and the control module is then subcooled back to described
The maximum allowable aperture of road valve body and the target superheat degree in the exit for crossing cold loop are modified, and according to revised
The maximum allowable aperture of the supercooling circuit valve body and the target superheat degree in the exit for crossing cold loop are subcooled back to described
Road valve body carries out PI control.
Multi-line system according to an embodiment of the present invention, when multi-line system is transported with pure refrigeration mode or main refrigeration mode
When row, control module judged whether the degree of supercooling of the inlet of cold loop is less than preset minimum subcooled temperature, if it is less,
The target superheat degree of maximum allowable aperture and the exit for crossing cold loop to supercooling circuit valve body is modified, and according to amendment
Afterwards supercooling circuit valve body maximum allowable aperture and cross cold loop exit target superheat degree to supercooling circuit valve body into
Row PI control.To be modified by the maximum opening to supercooling circuit valve body with the outlet superheat degree for crossing cold loop, to prevent
It only caused cold loop to become flat because valve body aperture is bigger than normal, system is caused to be deteriorated without degree of supercooling, indoor unit effect of freezing
Problem, so that system can obtain preferable refrigeration effect, and efficiency with higher.
According to one embodiment of present invention, the control module is by current maximum allowable the opening of the supercooling circuit valve body
Degree reduces the first preset value, to obtain the maximum allowable aperture of the revised supercooling circuit valve body.
According to one embodiment of present invention, the control module by it is described cross cold loop exit current goal mistake
Temperature increases by the second preset value, to obtain the target superheat degree in the revised exit for crossing cold loop.
According to one embodiment of present invention, the control module is in the degree of supercooling for judging the inlet for crossing cold loop
Whether it is less than before preset minimum subcooled temperature, it is default is also used to judge whether the aperture of the supercooling circuit valve body is greater than first
Aperture, and judge whether the time for carrying out PI adjusting to the supercooling circuit valve body is greater than the first preset time, wherein if institute
State supercooling circuit valve body aperture be greater than the described first default aperture, or to it is described supercooling circuit valve body carry out PI adjusting when
Between be greater than first preset time, the control module then further judge it is described cross cold loop inlet degree of supercooling
Whether preset minimum subcooled temperature is less than.
According to one embodiment of present invention, the control module according to revised supercooling circuit valve body most
After big permission aperture and the target superheat degree in the exit for crossing cold loop carry out PI control to the supercooling circuit valve body, also
Further judge whether the degree of supercooling of the inlet for crossing cold loop is more than or equal to the preset minimum subcooled temperature, wherein
If the degree of supercooling of the inlet for crossing cold loop is more than or equal to the preset minimum subcooled temperature, control module if, stops
Only the maximum allowable aperture to the supercooling circuit valve body and the target superheat degree in the exit for crossing cold loop are modified；
Otherwise, the control module continues to the exit of the maximum allowable aperture and mistake cold loop of the supercooling circuit valve body
Target superheat degree is modified.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of multi-line system according to an embodiment of the invention；
Fig. 2 is the process that the control method of circuit valve body is subcooled in multi-line system according to an embodiment of the invention
Figure；And
Fig. 3 is the flow chart that the control method of circuit valve body is subcooled in multi-line system according to an embodiment of the present invention.
Specific embodiment
The embodiment of the present invention is described below in detail, examples of the embodiments are shown in the accompanying drawings, wherein from beginning to end
Same or similar label indicates same or similar element or element with the same or similar functions.Below with reference to attached
The embodiment of figure description is exemplary, it is intended to is used to explain the present invention, and is not considered as limiting the invention.
With reference to the accompanying drawings come describe in the multi-line system proposed according to embodiments of the present invention be subcooled circuit valve body control
Method and multi-line system processed.
Fig. 1 is the structural schematic diagram of multi-line system according to an embodiment of the invention.As shown in Figure 1, the multi-connected machine
System may include outdoor unit 10, multiple indoor units 20, part flow arrangement 30 and control module 40.
Wherein, outdoor unit 10 may include compressor 11.Part flow arrangement 30 may include gas-liquid separator 31, First Heat Exchanger
32, the second heat exchanger 33, first throttle element 34 and supercooling circuit valve body 35.The first end and outdoor unit 10 of gas-liquid separator 31
One end be connected, the second end of gas-liquid separator 31 is connected with the first entrance for exchanging heat flow path of First Heat Exchanger 32, and first changes
The outlet of first heat exchange flow path of hot device 32 exchanges heat the entering of flow path by the first of first throttle element 34 and the second heat exchanger 33
Mouth is connected.The outlet of first heat exchange flow path of the second heat exchanger 33 is by being subcooled the second of circuit valve body 35 and the second heat exchanger 33
The entrance of heat exchange flow path is connected, the outlet of the second heat exchange flow path of the second heat exchanger 33 and the second heat exchange stream of First Heat Exchanger 32
The entrance on road is connected, and the outlet of the second heat exchange flow path of First Heat Exchanger 32 is respectively and in the other end and cool room of outdoor unit 10
One end of machine is connected.The outlet of first heat exchange flow path of the other end and the second heat exchanger 33 of refrigeration indoor unit is connected, gas-liquid point
Third end from device 31 is connected with one end of heating indoor unit, and the other end and the first of the second heat exchanger 33 for heating indoor unit change
The entrance of hot flowpath is connected.
First heat exchange flow path of the first heat exchange flow path of First Heat Exchanger 32, first throttle element 34 and the second heat exchanger 33
Constitute the main road of part flow arrangement 30, the second heat exchange flow path and First Heat Exchanger of supercooling circuit valve body 35, the second heat exchanger 33
32 the second heat exchange flow path constitutes the cold loop of crossing of part flow arrangement 30, and the entrance of cold loop was arranged in supercooling circuit valve body 35
Place.Wherein, First Heat Exchanger 32 and the second heat exchanger 33 can be plate heat exchanger, first throttle element 34 and supercooling return valve
Body 35 can be electric expansion valve.
When multi-line system is run with pure refrigeration mode, first throttle element 34 is shown in a fully open operation, from gas-liquid separation
The high-temperature gas mixture that device 31 comes out successively passes through First Heat Exchanger 32 and the second heat exchanger 33, in the second heat exchanger 33
The refrigerant in the exit of the first heat exchange flow path obtains degree of supercooling, and a part passed through cold loop and absorbs the heat that main road is released, most
Enter the low-voltage tube of outdoor unit 10 eventually, another part enters refrigeration indoor unit by the restricting element for the indoor unit that freezes, after heat absorption
Also enter the low-voltage tube of outdoor unit 10.
When multi-line system is run with main refrigeration mode, gas-liquid separator 31 will enter from the high-voltage tube of outdoor unit 10
High temperature gas-liquid mixture is separated into high pressure liquid and high pressure gas, wherein high pressure liquid is subcooled by First Heat Exchanger 32, high pressure gas then into
Enter to heat indoor unit, after heating indoor unit heat release, with the liquid refrigerants of the first heat exchange flow path from First Heat Exchanger 32 out
After mixing, into the second heat exchanger 33.The refrigerant come out from the first heat exchange flow path of the second heat exchanger 33, a part pass through supercooling
Circuit absorb main road release heat, finally with from refrigeration indoor unit come out refrigerant mix after into outdoor unit 10 low pressure
Pipe, another part enter refrigeration indoor unit by the restricting element for the indoor unit that freezes, and the space freezed to needs is freezed.
During multi-line system is run with pure refrigeration mode or main refrigeration mode, supercooling circuit valve body 35 is mainly used
In to the second heat exchanger 33 provide for be subcooled to refrigeration indoor unit refrigerant, system according to cross cold loop exit target
Degree of superheat SHB carries out PI adjusting to supercooling circuit valve body 35, so that crossing the degree of superheat SHm3 (SHm3 in the exit of cold loop
=Tm3-Tps3, wherein Tm3 is the temperature in the exit of the first heat exchange flow path of First Heat Exchanger 32, and Tps3 is the first heat exchange
The corresponding saturation temperature of pressure in the exit of the first heat exchange flow path of device 32) in a certain range.
But in some cases, for example, in outdoor temperature and indoor temperature all higher refrigeration, or it is outdoor
Machine heat exchanger occurs dirty stifled etc., and the refrigerant for being delivered to part flow arrangement 30 from outdoor unit 10 may have lower degree of supercooling (even
There is no degree of supercooling), then the refrigerant for initially entering supercooling circuit valve body 35 is gas-liquid two-phase state, the i.e. degree of supercooling in main road exit
SCm2 (SCm2=Tps2-Tm2, wherein Tps2 is that the pressure of the inlet of the first heat exchange flow path of the second heat exchanger 33 is corresponding
Saturation temperature, Tm2 are the temperature in the exit of the first heat exchange flow path of the second heat exchanger 33) very little, it is likely less than minimum value
(e.g., minimum value is 5 DEG C).Bigger by the refrigerant mass dryness fraction that circuit valve body 35 is subcooled, heat transfer effect is poorer (that is, supercooling return valve
Body 35 starts to become flat), the degree of superheat SHm3 so as to cause the exit for crossing cold loop is very big.Since degree of superheat SHm3 is much larger than mesh
Degree of superheat SHB is marked, according to PI control logic, will persistently open the aperture greater than cold loop valve body 35.Cold loop valve body 35 is served as
When aperture is opened greatly to maximum opening, system low-voltage pressure rise may cause, since 33 front and back heat transfer temperature difference of the second heat exchanger subtracts
Small, so that the second heat exchanger 33 loses the function of supercooling, supercooling circuit valve body 35 bypasses a large amount of refrigerants and is returned directly to compressor 11,
So that the refrigeration effect of refrigeration indoor unit is deteriorated.
Therefore, in an embodiment of the present invention, when multi-line system is run with pure refrigeration mode or main refrigeration mode,
Control module 40 judged whether the degree of supercooling SCm2 of the inlet of cold loop is less than preset minimum subcooled temperature, if it is lower,
Then the target superheat degree SHB in the maximum allowable aperture to supercooling circuit valve body 35 and the exit for crossing cold loop is modified, and
PI control is carried out according to revised supercooling circuit valve body 35.
According to one embodiment of present invention, control module 40 subtracts the current maximum allowable aperture that circuit valve body 35 is subcooled
Small first preset value, to obtain the maximum allowable aperture of revised supercooling circuit valve body 35.Wherein, current maximum allowable aperture
It can be demarcated according to the actual situation with the first preset value, for example, current maximum allowable aperture can be 480pls, first is default
Value can be 60.
Further, according to one embodiment of present invention, control module 40 will cross the current mesh in the exit of cold loop
It marks the degree of superheat and increases by the second preset value, to obtain the target superheat degree in the revised exit for crossing cold loop.Wherein, second is pre-
If value can be demarcated according to the actual situation, for example, the second preset value can be 5 DEG C.
Specifically, control module 40 is real-time during multi-line system is run with pure refrigeration or main refrigeration mode
The degree of supercooling of the inlet of cold loop was obtained, and it was judged.If the degree of supercooling for crossing the inlet of cold loop is less than
The current maximum opening (such as 480pls) of circuit valve body 35 will be then subcooled in preset minimum subcooled temperature (such as 5 DEG C), control module 40
Reduce the first preset value (such as 60), i.e., the maximum allowable aperture of revised supercooling circuit valve body 35=current is maximum allowable to be opened
The-the first preset value is spent, and the current goal degree of superheat that will cross the exit of cold loop increases the second preset value (such as 5 DEG C), that is, repairs
Target superheat degree=+ the second preset value of the current goal degree of superheat in the exit for crossing cold loop after just.Then, control module 40
According to the target superheat of the maximum allowable aperture of revised supercooling circuit valve body 35 and the revised exit for crossing cold loop
Degree carries out PI adjusting to supercooling circuit valve body 35.So that the aperture of supercooling circuit valve body 35 does not exceed reasonable value, effectively
It avoids causing to bypass a large amount of refrigerants because the aperture of supercooling circuit valve body 35 is excessive being returned directly in compressor 11, ensure that main road goes out
There is certain degree of supercooling at mouthful, effectively improve the refrigeration effect of system.
According to one embodiment of present invention, whether degree of supercooling of the control module 40 in the inlet for judging cold loop be small
Before preset minimum subcooled temperature, it is also used to judge whether the aperture of supercooling circuit valve body 35 is greater than the first default aperture, and
Judge whether the time that PI adjusting is carried out to supercooling circuit valve body 35 is greater than the first preset time, wherein if supercooling return valve
The aperture of body 35 be greater than the first default aperture, or to supercooling circuit valve body 35 carry out PI adjusting time be greater than first it is default when
Between, control module 40 then further judged whether the degree of supercooling of the inlet of cold loop is less than preset minimum subcooled temperature.
Wherein, the first default aperture and the first preset time can be demarcated according to the actual situation, for example, the first default aperture can be
The maximum opening that circuit valve body 35 allows, or the value being calculated according to control logic is subcooled.
Specifically, supercooling circuit valve body 35 has an initial opening (initial opening when system is switched on operation every time
It can be 0pls, or be set according to the actual situation).When system brings into operation, when the degree of superheat is much larger than target superheat
When spending, according to PI control logic, the aperture greater than cold loop valve body 35 will be persistently opened.It accidentally corrects, can first judge in order to prevent
Whether the current aperture of cold loop valve body 35 is greater than the first default aperture, or supercooling circuit valve body 35 carries out the time of PI adjusting
Whether it is greater than the first preset time, if the current aperture of supercooling circuit valve body 35 is greater than the first default aperture, or is subcooled back
The time that road valve body 35 carries out PI adjusting is greater than the first preset time, and control module 40 then further judged entering for cold loop
Whether the degree of supercooling at mouthful is less than preset minimum subcooled temperature, to effectively prevent the mistake amendment of system.
According to one embodiment of present invention, control module 40 permits according to the maximum of revised supercooling circuit valve body 35
Perhaps after aperture and the target superheat degree in the exit for crossing cold loop carry out PI control to supercooling circuit valve body 35, also further judgement
Whether the degree of supercooling for crossing the inlet of cold loop is more than or equal to preset minimum subcooled temperature, wherein if crossing the entrance of cold loop
The degree of supercooling at place is more than or equal to preset minimum subcooled temperature, and control module 40 then stops to the maximum allowable of supercooling circuit valve body 35
Aperture and the target superheat degree in the exit for crossing cold loop are modified；Otherwise, control module 40 continues to supercooling circuit valve body
35 maximum allowable aperture and the target superheat degree in the exit for crossing cold loop are modified.
Specifically, being opened when system enters correction logic according to revised supercooling the maximum allowable of circuit valve body 35
After the target superheat degree in the exit of degree and cold loop excessively carries out PI control to supercooling circuit valve body 35, cold loop was judged again
The degree of supercooling of inlet whether be more than or equal to preset minimum subcooled temperature, if it is, illustrating that the bypass of cold loop (was run
Gas) phenomenon made moderate progress, system has had super cooling effect, at this time can gradually stable supercooling circuit valve body 35 aperture extremely
Optimal aperture, so that system has preferable refrigeration effect, and efficiency with higher.
If crossing the degree of supercooling of the inlet of cold loop still less than preset minimum subcooled temperature, control after a wheel is adjusted
Molding block 40 then continue to supercooling circuit valve body 35 maximum allowable aperture and cross cold loop exit target superheat degree into
The maximum allowable aperture of revised supercooling circuit valve body 35 is reduced the first preset value, to be corrected again by row amendment
The target superheat degree in the revised exit for crossing cold loop is increased by the by the maximum allowable aperture of supercooling circuit valve body 35 afterwards
Two preset values, to obtain the target superheat degree in the revised exit for crossing cold loop again, then, according to revised again
Be subcooled circuit valve body 35 maximum allowable aperture and cross cold loop exit target superheat degree to supercooling circuit valve body 35 into
Row PI control, to obtain lower maximum allowable aperture, further increases degree of supercooling, repeatedly a few wheel adjustment, so that supercooling
The aperture of circuit valve body 35 is optimal value, to obtain preferable refrigeration effect, and efficiency with higher.
It should be noted that when the maximum allowable aperture that circuit valve body 35 is subcooled is adapted to a certain value, if system is stopped
Machine or compressor 11 exit PI control, then the maximum allowable aperture that circuit valve body 35 is subcooled are adjusted to initial maximum aperture, with
Multi-line system is set to carry out PI control according to the initial maximum aperture of supercooling circuit valve body 35 when running again.
Therefore, multi-line system according to an embodiment of the present invention, by the maximum opening and supercooling that circuit valve body is subcooled
The outlet superheat degree in circuit is modified, and to prevent from causing cold loop to become flat because valve body aperture is bigger than normal, leads to system
Without degree of supercooling, the problem of indoor unit effect of freezing is deteriorated so that system can obtain preferable refrigeration effect, and have compared with
High efficiency.
To make those skilled in the art better understand the present invention, Fig. 2 is according to an embodiment of the invention multi-joint
The flow chart of the control method of circuit valve body is subcooled in machine system.As shown in Fig. 2, circuit valve body is subcooled in the multi-line system
Control method can comprise the following steps that
S101 brings into operation.
S102, judged whether the degree of superheat SHm3 in the exit of cold loop is greater than target superheat degree SHB.If so, holding
Row step S103；If not, return step S102.
S103 carries out PI adjusting to supercooling circuit valve body, and supercooling circuit valve body is persistently opened greatly.
S104, the aperture for judging whether there is supercooling circuit valve body are greater than the first default aperture X, or supercooling circuit valve body
The time for carrying out PI adjusting is greater than the first preset time T.If so, executing step S105；If not, return step S104.
S105, judged whether the degree of supercooling SCm2 of the inlet of cold loop is less than preset minimum subcooled temperature B.If
It is to execute step S106；If not, executing step S109.
The current maximum allowable aperture that circuit valve body is subcooled is reduced the first preset value C, and will cross going out for cold loop by S106
Current goal degree of superheat SHB at mouthful increases by the second preset value D.
S107 carries out PI to supercooling circuit valve body according to the maximum allowable aperture and SHB of revised supercooling circuit valve body
It adjusts.
S108, judges whether SCm2 is more than or equal to B.If so, executing step S109；If not, return step S106.
S109 obtains the optimal aperture of supercooling circuit valve body.
In conclusion the control method of circuit valve body is subcooled in multi-line system according to an embodiment of the present invention, when multi-joint
When machine system is run with pure refrigeration mode or main refrigeration mode, if crossing the degree of supercooling of the inlet of cold loop less than preset
Minimum subcooled temperature, then the maximum allowable aperture to supercooling circuit valve body and the target superheat degree in the exit for crossing cold loop are repaired
Just, and according to the maximum allowable aperture of revised supercooling circuit valve body and the target superheat degree in the exit for crossing cold loop to mistake
Cold loop valve body carries out PI control.To by supercooling circuit valve body maximum opening and cross cold loop outlet superheat degree into
Row amendment causes system without degree of supercooling, freeze indoor unit to prevent from causing cold loop to become flat because valve body aperture is bigger than normal
The problem of effect is deteriorated, so that system can obtain preferable refrigeration effect, and efficiency with higher.
Fig. 3 is the flow chart that the control method of circuit valve body is subcooled in multi-line system according to an embodiment of the present invention.?
In the embodiment of the present invention, multi-line system may include that outdoor unit, multiple indoor units and part flow arrangement, part flow arrangement may include
Cold loop, wherein the inlet of cold loop was arranged in supercooling circuit valve body.
As shown in figure 3, the control method of circuit valve body is subcooled in the multi-line system can comprise the following steps that
S1 judged the inlet of cold loop when multi-line system is run with pure refrigeration mode or main refrigeration mode
Degree of supercooling whether be less than preset minimum subcooled temperature.
S2, if the degree of supercooling for crossing the inlet of cold loop is less than preset minimum subcooled temperature, to supercooling circuit valve body
Maximum allowable aperture and cross the target superheat degree in exit of cold loop and be modified.
S3, according to the target superheat of the maximum allowable aperture of revised supercooling circuit valve body and the exit for crossing cold loop
Degree carries out PI control to supercooling circuit valve body.
According to one embodiment of present invention, the current maximum allowable aperture that circuit valve body is subcooled is reduced first to preset
Value, to obtain the maximum allowable aperture of revised supercooling circuit valve body.
According to one embodiment of present invention, the current goal degree of superheat for crossing the exit of cold loop is increased by second to preset
Value, to obtain the target superheat degree in the revised exit for crossing cold loop.
According to one embodiment of present invention, the degree of supercooling in the inlet for judging cold loop whether be less than it is preset most
Before small degree of supercooling, further includes: judge whether the aperture that circuit valve body is subcooled is greater than the first default aperture, and judge to being subcooled back
Whether the time that road valve body carries out PI adjusting is greater than the first preset time；If it is default that the aperture that circuit valve body is subcooled is greater than first
Aperture, or the time for carrying out PI adjusting to supercooling circuit valve body are greater than the first preset time, then further judgement is subcooled back
Whether the degree of supercooling of the inlet on road is less than preset minimum subcooled temperature.
According to one embodiment of present invention, in the maximum allowable aperture and supercooling according to revised supercooling circuit valve body
After the target superheat degree in the exit in circuit carries out PI control to supercooling circuit valve body, further includes: judged the entrance of cold loop
Whether the degree of supercooling at place is more than or equal to preset minimum subcooled temperature；If the degree of supercooling for crossing the inlet of cold loop is more than or equal to pre-
If minimum subcooled temperature, then stop to supercooling circuit valve body maximum allowable aperture and cross cold loop exit target superheat
Degree is modified；Otherwise, continue the maximum allowable aperture to supercooling circuit valve body and cross the target superheat in the exit of cold loop
Degree is modified.
It is not disclosed it should be noted that being subcooled in the multi-line system of the embodiment of the present invention in the control method of circuit valve body
Details, please refer to details disclosed in the multi-line system of the embodiment of the present invention, specific which is not described herein again.
The control method of circuit valve body is subcooled in multi-line system according to an embodiment of the present invention, when multi-line system is with pure
When refrigeration mode or main refrigeration mode are run, if the degree of supercooling for crossing the inlet of cold loop is less than preset minimum supercooling
Degree, then the maximum allowable aperture to supercooling circuit valve body and the target superheat degree in the exit for crossing cold loop are modified, and root
According to the maximum allowable aperture of revised supercooling circuit valve body and the target superheat degree in the exit of cold loop excessively to cold loop excessively
Valve body carries out PI control.To be repaired by the maximum opening to supercooling circuit valve body with the outlet superheat degree for crossing cold loop
Just, it prevents from causing cold loop to become flat because valve body aperture is bigger than normal, causes system without degree of supercooling, indoor unit effect of freezing
The problem of variation, so that system can obtain preferable refrigeration effect, and efficiency with higher.
In the description of the present invention, it is to be understood that, term " center ", " longitudinal direction ", " transverse direction ", " length ", " width ",
" thickness ", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom" "inner", "outside", " up time
The orientation or positional relationship of the instructions such as needle ", " counterclockwise ", " axial direction ", " radial direction ", " circumferential direction " be orientation based on the figure or
Positional relationship is merely for convenience of description of the present invention and simplification of the description, rather than the device or element of indication or suggestion meaning must
There must be specific orientation, be constructed and operated in a specific orientation, therefore be not considered as limiting the invention.
In addition, term " first ", " second " are used for descriptive purposes only and cannot be understood as indicating or suggesting relative importance
Or implicitly indicate the quantity of indicated technical characteristic.Define " first " as a result, the feature of " second " can be expressed or
Implicitly include at least one this feature.In the description of the present invention, the meaning of " plurality " is at least two, such as two, three
It is a etc., unless otherwise specifically defined.
In the present invention unless specifically defined or limited otherwise, term " installation ", " connected ", " connection ", " fixation " etc.
Term shall be understood in a broad sense, for example, it may be being fixedly connected, may be a detachable connection, or integral；It can be mechanical connect
It connects, is also possible to be electrically connected；It can be directly connected, can also can be in two elements indirectly connected through an intermediary
The interaction relationship of the connection in portion or two elements, unless otherwise restricted clearly.For those of ordinary skill in the art
For, the specific meanings of the above terms in the present invention can be understood according to specific conditions.
In the present invention unless specifically defined or limited otherwise, fisrt feature in the second feature " on " or " down " can be with
It is that the first and second features directly contact or the first and second features pass through intermediary mediate contact.Moreover, fisrt feature exists
Second feature " on ", " top " and " above " but fisrt feature be directly above or diagonally above the second feature, or be merely representative of
First feature horizontal height is higher than second feature.Fisrt feature can be under the second feature " below ", " below " and " below "
One feature is directly under or diagonally below the second feature, or is merely representative of first feature horizontal height less than second feature.
In the description of this specification, reference term " one embodiment ", " some embodiments ", " example ", " specifically show
The description of example " or " some examples " etc. means specific features, structure, material or spy described in conjunction with this embodiment or example
Point is included at least one embodiment or example of the invention.In the present specification, schematic expression of the above terms are not
It must be directed to identical embodiment or example.Moreover, particular features, structures, materials, or characteristics described can be in office
It can be combined in any suitable manner in one or more embodiment or examples.In addition, without conflicting with each other, the skill of this field
Art personnel can tie the feature of different embodiments or examples described in this specification and different embodiments or examples
It closes and combines.
Although the embodiments of the present invention has been shown and described above, it is to be understood that above-described embodiment is example
Property, it is not considered as limiting the invention, those skilled in the art within the scope of the invention can be to above-mentioned
Embodiment is changed, modifies, replacement and variant.
Claims (10)
1. the control method of circuit valve body is subcooled in a kind of multi-line system, which is characterized in that the multi-line system includes room
Outer machine, multiple indoor units and part flow arrangement, the part flow arrangement included cold loop, and the supercooling circuit valve body is arranged described
The inlet for crossing cold loop, the described method comprises the following steps:
When the multi-line system is run with pure refrigeration mode or main refrigeration mode, the inlet for crossing cold loop is judged
Degree of supercooling whether be less than preset minimum subcooled temperature；
If the degree of supercooling of the inlet for crossing cold loop is less than the preset minimum subcooled temperature, cold loop is crossed to described
The maximum allowable aperture of valve body and the target superheat degree in the exit for crossing cold loop are modified；And
According to the target mistake of the maximum allowable aperture of the revised supercooling circuit valve body and the exit for crossing cold loop
Temperature carries out PI control to the supercooling circuit valve body.
2. the control method of circuit valve body is subcooled in multi-line system as described in claim 1, which is characterized in that by the mistake
The current maximum allowable aperture of cold loop valve body reduces the first preset value, to obtain revised supercooling circuit valve body most
It is big to allow aperture.
3. the control method of circuit valve body is subcooled in multi-line system as described in claim 1, which is characterized in that by the mistake
The current goal degree of superheat in the exit of cold loop increases by the second preset value, to obtain the revised outlet for crossing cold loop
The target superheat degree at place.
4. the control method of circuit valve body is subcooled in multi-line system as claimed in any one of claims 1-3, feature exists
In before judging whether the degree of supercooling of the inlet for crossing cold loop is less than preset minimum subcooled temperature, further includes:
Judge it is described supercooling circuit valve body aperture whether be greater than the first default aperture, and judge to the supercooling circuit valve body into
Whether the time that row PI is adjusted is greater than the first preset time；
If the aperture of the supercooling circuit valve body is greater than the described first default aperture, or carries out to the supercooling circuit valve body
The time that PI is adjusted is greater than first preset time, then further judges that the degree of supercooling of the inlet for crossing cold loop is
It is no to be less than the preset minimum subcooled temperature.
5. the control method of circuit valve body is subcooled in multi-line system as claimed in claim 4, which is characterized in that repaired in basis
The maximum allowable aperture of supercooling circuit valve body after just and the target superheat degree in the exit for crossing cold loop are to described
After the progress PI control of circuit valve body is subcooled, further includes:
Judge whether the degree of supercooling of the inlet for crossing cold loop is more than or equal to the preset minimum subcooled temperature；
If the degree of supercooling of the inlet for crossing cold loop is more than or equal to the preset minimum subcooled temperature, stop to described
The target superheat degree of maximum allowable aperture and the exit for crossing cold loop that circuit valve body is subcooled is modified；
Otherwise, continue the maximum allowable aperture to the supercooling circuit valve body and the target superheat in the exit for crossing cold loop
Degree is modified.
6. a kind of multi-line system characterized by comprising
Outdoor unit；
Multiple indoor units；
Part flow arrangement, the part flow arrangement included cold loop, and the inlet for crossing cold loop is arranged in supercooling circuit valve body；
Control module, the control module are used to run when the multi-line system with pure refrigeration mode or main refrigeration mode
When, judge whether the degree of supercooling of the inlet for crossing cold loop is less than preset minimum subcooled temperature, wherein if the supercooling
The degree of supercooling of the inlet in circuit is less than the preset minimum subcooled temperature, and the control module is then to supercooling circuit valve body
Maximum allowable aperture and the target superheat degree in exit for crossing cold loop be modified, and according to the revised mistake
The maximum allowable aperture of cold loop valve body and the target superheat degree in the exit for crossing cold loop are to supercooling circuit valve body
Carry out PI control.
7. multi-line system as claimed in claim 6, which is characterized in that the control module is by the supercooling circuit valve body
Current maximum allowable aperture reduces the first preset value, to obtain the maximum allowable aperture of the revised supercooling circuit valve body.
8. multi-line system as claimed in claim 6, which is characterized in that the control module by it is described cross cold loop outlet
The current goal degree of superheat at place increases by the second preset value, to obtain the target superheat in the revised exit for crossing cold loop
Degree.
9. the multi-line system as described in any one of claim 6-8, which is characterized in that the control module is described in the judgement
Whether the degree of supercooling for crossing the inlet of cold loop is less than before preset minimum subcooled temperature, is also used to judge the supercooling return valve
Whether the aperture of body is greater than the first default aperture, and judges whether the time for carrying out PI adjusting to the supercooling circuit valve body is greater than
First preset time, wherein
If the aperture of the supercooling circuit valve body is greater than the described first default aperture, or carries out to the supercooling circuit valve body
The time that PI is adjusted is greater than first preset time, and the control module then further judges the entrance for crossing cold loop
Whether the degree of supercooling at place is less than preset minimum subcooled temperature.
10. multi-line system as claimed in claim 9, which is characterized in that the control module is according to revised described
The maximum allowable aperture of circuit valve body and the target superheat degree in the exit for crossing cold loop is subcooled to the supercooling return valve
After body carries out PI control, it is described preset also further to judge whether the degree of supercooling of the inlet for crossing cold loop is more than or equal to
Minimum subcooled temperature, wherein
If the degree of supercooling of the inlet for crossing cold loop is more than or equal to the preset minimum subcooled temperature, the control module
Then stop carrying out the maximum allowable aperture of the supercooling circuit valve body and the target superheat degree in the exit for crossing cold loop
Amendment；
Otherwise, the control module continues the maximum allowable aperture and the outlet for crossing cold loop to the supercooling circuit valve body
The target superheat degree at place is modified.
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| CN201611076285.2A CN106524338B (en) | 2016-11-25 | 2016-11-25 | Multi-line system and its supercooling circuit valve body control method |
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| CN111928410B (en) * | 2020-06-30 | 2023-05-26 | 青岛海尔空调器有限总公司 | Control method for multi-split air conditioning unit |
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