Note: Descriptions are shown in the official language in which they were submitted.
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ANTI-SLUGGING CONTROL METHOD AND CONTROL APPARATUS FOR
A1R-CONDITIONING SYSTEM, AND AIR-CONDITIONING SYSTEM
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is based on and claims priorities to Chinese Patent
Application No.
201611027983.3 and Chinese Patent Application No. 201611034105.4, both filed
with the State
Intellectual Property Office of P. R. China on November 17, 2016, the entire
content of which are
incorporated herein by reference.
FIELD
The present disclosure relates to the field of air conditioner technology, and
more particularly to a
control method of anti-liquid-slugging of air conditioning system and a
control device of
anti-liquid-slugging of air conditioning system, and an air conditioning
system.
BACKGROUND
In an air conditioning system, several factors, such as too much refrigerant
or lubricating oil,
excessive adjustment degree (opening degree) of expansion valve (or adjusting
valve), instability of
thermal load of an evaporator and the like, may cause that liquid refrigerant
enters into an air cylinder
of a compressor, such that the compressor is suffered from liquid-slugging. As
a result, long-time and
heavy liquid-slugging may cause a valve plate of the compressor deformed,
broken or even cause the
compressor permanently damaged.
In related arts, in order to ensure that the refrigerant sucked back through
an air inlet of the
compressor is gaseous, suction superheat degree of the air conditioning system
is general monitored in
real time, thereby preventing that the liquid refrigerant enters into the
compressor and avoiding that
the compressor is suffered from the liquid-slugging. However, generally the
value of the suction
superheat degree of the air conditioning system is relatively small, which is
not easy to be detected
and controlled. Therefore, an accuracy of anti-liquid-slugging control of the
compressor is relatively
low and reliability is poor.
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Therefore, there is a need to improve the control method for preventing the
compressor from the
liquid-slugging in the related arts.
SUMMARY
Embodiments of the present disclosure seek to solve at least one of the
problems existing in the
related art to at least some extent.
In order to achieve above objectives, embodiments of a first aspect of the
present disclosure
provide a control method of anti-liquid-slugging of air conditioning system.
The control method
includes acquiring a drain superheat degree of a compressor in real time,
monitoring the drain
superheat degree during an operating process of the air conditioning system;
when the drain superheat
degree is less than a first preset value for a first preset time period,
controlling a timer to start timing;
and when a counted time period of the timer reaches a second preset time
period, controlling an
outdoor unit of the air conditioning system to shut down for preventing the
compressor from the
liquid-slugging.
In at least one embodiment, during a timing process of the timer, when the
drain superheat degree
is greater than or equal to the first preset value for a third preset time
period, resetting the timer and
continuing to determine whether the drain superheat degree satisfies a
condition that the timer starts
timing.
In at least one embodiment, after controlling the outdoor unit to shut down,
the control method
further includes determining whether a number of anti-liquid-slugging
protection activated by the air
conditioning system during a fourth preset time period exceeds a preset
number, while the number of
the anti-liquid-slugging protection activated by the air conditioning system
during the fourth preset
time period exceeds the preset number, controlling the outdoor unit to be
unrecoverable without being
powered off; and while the number of the anti-liquid-slugging protection
activated by the air
conditioning system during the fourth preset time period does not exceed the
preset number, resetting
the timer, and controlling the outdoor unit to restart after a fifth preset
time period.
In at least one embodiment, the air conditioning system includes the
compressor, a condenser and
an evaporator, and acquiring the drain superheat degree of the compressor in
real time includes:
detecting temperature of an air outlet of the compressor, and detecting
temperature of a middle part of
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the condenser and temperature of a middle part of the evaporator; when the air
conditioning system is
in a refrigerating mode, calculating the drain superheat degree of the
compressor according to the
temperature of the air outlet and the temperature of the middle part of the
condenser; and when the air
conditioning system is in a heating mode, calculating the drain superheat
degree of the compressor
according to the temperature of the air outlet and the temperature of the
middle part of the evaporator.
In at least one embodiment, acquiring the drain superheat degree of the
compressor in real time
includes: detecting a pressure of an air outlet of the compressor and
detecting temperature of the air
outlet of the compressor; and calculating the drain superheat degree of the
compressor according to
the pressure of the air outlet and the temperature of the air outlet.
In at least one embodiment, the first preset time period may be 20 minutes,
the second preset
time period may be 30 minutes, the third preset time period may be 5 minutes,
the fourth preset time
period may be 120 minutes and the fifth preset time period may be 6 minutes.
With the control method of anti-liquid-slugging of air conditioning system
according to
embodiments of the present disclosure, by acquiring the drain superheat degree
of the compressor in
real time, and by monitoring the drain superheat degree during the operating
process of the air
conditioning system, the timer is controlled to start timing when the drain
superheat degree is less
than the first preset value for the first preset time period; and the outdoor
unit of the air conditioning
system is controlled to shut down for preventing the compressor from the
liquid-slugging when the
counted time period of the timer reaches the second preset time period.
Therefore, the control method
of anti-liquid-slugging of air conditioning system according to embodiments of
the present disclosure
may realize anti-liquid-slugging protection by monitoring the drain superheat
degree of the
compressor in real time, such that it may be ensured that refrigerant sucked
back through an air inlet
of the compressor is gaseous, thereby preventing liquid refrigerant from
entering into the compressor
and avoiding the compressor being suffered from the liquid-slugging. In
addition, since the value of
the drain superheat degree is relatively large, which is easy for data
detection and anti-liquid-slugging
control, an accuracy of anti-liquid-slugging control is improved and security
and reliability during the
operating process of the air conditioning system are improved.
In order to achieve above objectives, embodiments of a second aspect of the
present disclosure
provide a non-transitory computer readable storage medium, having computer
programs stored
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thereon. When the computer programs are executed by a processor, the control
method of
anti-liquid-slugging of air conditioning system according to embodiments of
the first aspect is
realized.
In order to achieve above objectives, embodiments of a third aspect of the
present disclosure
provide a control device of anti-liquid-slugging of air conditioning system.
The control device
includes: an acquiring module, configured to acquire a drain superheat degree
of a compressor in real
time; a monitoring module, configured to monitor the drain superheat degree
during an operating
process of the air conditioning system; and a control module, configured to,
when the drain superheat
degree is less than a first preset value for a first preset time period,
control a timer to start timing; and
when a counted time period of the timer reaches a second preset time period,
control an outdoor unit
of the air conditioning system to shut down for preventing the compressor from
the liquid-slugging.
In at least one embodiment, during a timing process of the timer, when the
drain superheat degree
is greater than or equal to the first preset value for a third preset time
period, the control module is
configured to reset the timer and continue to determine whether the drain
superheat degree satisfies a
condition that the timer starts timing.
In at least one embodiment, after the outdoor unit is controlled to shut down,
the control module
is further configured to determine, whether a number of anti-liquid-slugging
protection activated by
the air conditioning system during a fourth preset time period exceeds a
preset number, while the
number of the anti-liquid-slugging protection activated by the air
conditioning system during the
fourth preset time period exceeds the preset number, the control module is
configured to control the
outdoor unit to be unrecoverable without being powered off; and while the
number of the
anti-liquid-slugging protection activated by the air conditioning system
during the fourth preset time
period does not exceed the preset number, the control module is configured to
reset the timer, and
control the outdoor unit to restart after a fifth preset time period.
In at least one embodiment, the air conditioning system includes the
compressor, a condenser and
an evaporator, and the control device further includes: a first temperature
sensor arranged at an air
outlet of the compressor and configured to detect temperature of the air
outlet of the compressor; a
second temperature sensor arranged at a middle part of the condenser and
configured to detect
temperature of the middle part of the condenser; and a third temperature
sensor arranged at a middle
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part of the evaporator and configured to detect temperature of the middle part
of the evaporator; the
acquiring module is further configured to calculate the drain superheat degree
of the compressor
according to the temperature of the air outlet and the temperature of the
middle part of the condenser
when the air conditioning system is in a refrigerating mode; and to calculate
the drain superheat
degree of the compressor according to the temperature of the air outlet and
the temperature of the
middle part of the evaporator when the air conditioning system is in a heating
mode.
In at least one embodiment, the control device further includes a temperature
sensor and a
pressure sensor arranged at an air outlet of the compressor, the temperature
sensor is configured to
detect temperature of the air outlet of the compressor and the pressure sensor
is configured to detect
pressure of the air outlet of the compressor, and the acquiring module is
configured to calculate the
drain superheat degree of the compressor according to the temperature of the
air outlet and the
pressure of the air outlet.
In at least one embodiment, the first preset time period may be 20 minutes,
the second preset
time period may be 30 minutes, the third preset time period may be 5 minutes,
the fourth preset time
period may be 120 minutes and the fifth preset time period may be 6 minutes.
With the control device of anti-liquid-slugging of air conditioning system
according to
embodiments of the present disclosure, by acquiring the drain superheat degree
of the compressor in
real time with the acquiring module, and by monitoring the drain superheat
degree with the
monitoring module during the operating process of the air conditioning system,
the control module is
configured to control the timer to start timing when the drain superheat
degree is less than the first
preset value for the first preset time period; and the control module is
configured to control the
outdoor unit of the air conditioning system to shut down for preventing the
compressor from the
liquid-slugging when the counted time period of the timer reaches the second
preset time period.
Therefore, the control device of anti-liquid-slugging of air conditioning
system according to
embodiments of the present disclosure may realize anti-liquid-slugging
protection by monitoring the
drain superheat degree of the compressor in real time, such that it may be
ensured that refrigerant
sucked back through an air inlet of the compressor is gaseous, thereby
preventing liquid refrigerant
from entering into the compressor and avoiding the compressor being suffered
from the
liquid-slugging. In addition, since the value of the drain superheat degree is
relatively large, which is
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easy for data detection and anti-liquid-slugging control, an accuracy of the
anti-liquid-slugging control
is improved and security and reliability during the operating process of the
air conditioning system are
improved.
In order to achieve above objectives, embodiments of a fourth aspect of the
present disclosure
provide an air conditioning system. The air conditioning system includes the
control device of
anti-liquid-slugging of air conditioning system according to above
embodiments.
With the air conditioning system according to embodiments of the present
disclosure, an
anti-liquid-slugging protection is realized by monitoring the drain superheat
degree of the compressor
in real time with the above control device of anti- liquid-slugging of air
conditioning system, such that
it may be ensured that refrigerant sucked back through an air inlet of the
compressor is gaseous,
thereby preventing liquid refrigerant from entering into the compressor and
avoiding the compressor
being suffered from the liquid-slugging. In addition, since the value of the
drain superheat degree is
relatively large, which is easy for data detection and anti-liquid-slugging
control, an accuracy of
anti-liquid-slugging control is improved and security and reliability during
the operating process of
the air conditioning system are improved.
Additional aspects and advantages of embodiments of present disclosure will be
given in part in
the following descriptions, become apparent in part from the following
descriptions, or be learned
from the practice of the embodiments of the present disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a flow chart illustrating a control method of anti-liquid-slugging
of air conditioning
system according to an embodiment of the present disclosure;
Fig. 2 is a diagram illustrating a pressure vs enthalpy curve of an air
conditioning system
according to an embodiment of the present disclosure;
Fig. 3 is a flow chart illustrating a control method of anti-liquid-slugging
of air conditioning
system according to another embodiment of the present disclosure;
Fig. 4 is a flow chart illustrating a control method of anti-liquid-slugging
of air conditioning
system according to a specific embodiment of the present disclosure; Fig. 5 is
a block diagram
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illustrating a control device of anti-liquid-slugging of air conditioning
system according to an
embodiment of the present disclosure;
Fig. 6 is a schematic diagram illustrating an air conditioning system
according to an embodiment
of the present disclosure;
Fig. 7 is a block diagram illustrating a control device of anti-liquid-
slugging of air conditioning
system according to another embodiment of the present disclosure;
Fig. 8 is a schematic diagram illustrating an air conditioning system
according to another
embodiment of the present disclosure; and
Fig. 9 is a block diagram illustrating an air conditioning system according to
embodiments of the
present disclosure.
Reference numerals:
acquiring module 10, monitoring module 20, control module 30, fourth
temperature sensor 40,
pressure sensor 50, and timer 60;
first temperature sensor 70, second temperature sensor 80, third temperature
sensor 90,
calculating module 11;
compressor 100, evaporator 200, condenser 300, air conditioning system 400,
and control device
500 of anti-liquid-slugging of air conditioning system.
DETAILED DESCRIPTION
Descriptions will be made in detail to embodiments of the present disclosure,
examples of the
embodiments are shown in drawings, in which the same or similar elements and
the elements having
same or similar functions are denoted by like reference numerals throughout
the descriptions. The
embodiments described herein with reference to drawings are explanatory, are
intended to understand
the present disclosure, and are not construed to limit the present disclosure.
A control method of anti-liquid-slugging of air conditioning system and a
control device of
anti-liquid-slugging of air conditioning system and an air conditioning system
provided in
embodiments of the present disclosure will be described with reference to
drawings.
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Fig. 1 is a flow chart illustrating a control method of anti-liquid-slugging
of air conditioning
system according to an embodiment of the present disclosure. As illustrated in
Fig. 1, the control
method of anti-liquid-slugging of air conditioning system includes the
followings.
in block SIO, drain superheat degree DSH of a compressor is acquired in real
time, and the drain
superheat degree DSH is monitored during an operating process of an air
conditioning system.
According to an embodiment of the present disclosure, acquiring the drain
superheat degree DSH
of the compressor in real time includes the following. Pressure P of an air
outlet of the compressor is
detected, and temperature Tc of the air outlet of the compressor is detected.
The drain superheat
degree DSH of the compressor is calculated according to the pressure P of the
air outlet and the
temperature Tc of the air outlet.
Specifically, based on analysis of the operating process of the air
conditioning system, a pressure
vs enthalpy diagram illustrated in Fig. 2 may be obtained. In the diagram, a
longitudinal coordinate
represents a logarithm value LogP of an absolute pressure of the air
conditioning system, while a
horizontal coordinate represents a specific enthalpy value b of the air
conditioning system. As
illustrated in Fig. 2, the air conditioning system is in a superheat and
exothermic phase indicated by
segments 1-2, where gaseous refrigerant with high temperature and high
pressure is exhausted from
the air outlet of the compressor. The air conditioning system is in a constant
pressure and exothermic
phase indicated by segments 2-4. The air conditioning system is in a constant
pressure and
endothermic phase indicated by segments 5-6. The air conditioning system is in
a superheat and
endothermic phase indicated by segments 6-7, where the refrigerant is sucked
back through an air
inlet of the compressor. As illustrated in Fig. 2, the drain superheat degree
DSH of the air conditioning
system corresponds to the suction superheat degree SSH, and the value of the
drain superheat degree
DSH is greater than the value of the suction superheat degree SSH. Therefore,
when the drain
superheat degree DSH is within a predetermined range, it may be ensured that
the refrigerant sucked
back through the air inlet of the compressor is gaseous.
During the operating process of the air conditioning system, the pressure P of
the air outlet of the
compressor and the temperature Tc of the air outlet are detected in real time,
an acquiring module may
be configured to acquire drain saturation temperature Tp according to the
pressure P of the air outlet
of the compressor detected in real time, and to calculate a difference between
the temperature Tc of
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the air outlet and the drain saturation temperature Tp as real-time drain
superheat degree DSH.
Therefore, the real-time drain superheat degree DSH may be used for anti-
liquid-slugging control.
In block S20, when the drain superheat degree DSH is less than a first preset
value MI for a first
preset time period ti, a timer is controlled to start timing.
In block S30, when a counted time period t of the timer reaches a second
preset time period t2, an
outdoor unit of the air conditioning system is controlled to shut down for
preventing the compressor
from the liquid-slugging.
According to a specific embodiment of the present disclosure, the first preset
time period t I may
be 20 minutes, the second preset time period t2 may be 30 minutes, and the
first preset value MI may
be A C.
Specifically, the drain superheat degree DSH of the compressor is acquired in
real time, and the
drain superheat degree DSH is monitored during the operating process of the
air conditioning system
to determine whether the drain superheat degree DSH of the air conditioning
system is greater than or
equal to the first preset value MI. When the drain superheat degree DSH is
greater than or equal to the
first preset value M1 (such as A C), it is indicated that a suction superheat
degree SSH of the air
conditioning system is sufficiently large, such that the outdoor unit of the
air conditioning system is
controlled to operate normally. The refrigerant sucked back through the air
inlet of the compressor is
gaseous. When the drain superheat degree DSH is less than the first preset
value Ml, it is further
determined whether a duration reaches the first preset time period ti (such as
20 minutes). When the
duration reaches the first preset time period t I, the timer is controlled to
start timing.
Further, it is determined whether the counted time period t of the timer
reaches a second preset
time period t2 (such as 30 minutes). When the counted time period t of the
timer reaches the second
preset time period t2, that is the duration when the drain superheat degree
DSH is less than the first
preset value MI reaches a second preset time period t2, it is indicated that
the suction superheat
degree SSH of the air conditioning system is relatively low. The outdoor unit
of the air conditioning
system is controlled to shut down for preventing liquid refrigerant from being
sucked back through the
air inlet of the compressor and avoiding the compressor being suffered from
the liquid-slugging.
According to an embodiment of the present disclosure, during a timing process
of the timer,
when the drain superheat degree DSH is greater than or equal to the first
preset value MI for a third
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preset time period t3, the timer is reset and the control method continues to
determine whether the
drain superheat degree satisfies a condition that the timer starts timing.
According to a specific embodiment of the present disclosure, the third preset
time period t3 may
be 5 minutes.
Specifically, during the timing process of the timer, the drain superheat
degree DSH is monitored
in real time. When the drain superheat degree DSH is greater than or equal to
the first preset value MI
(such as A C), it is further determined whether a duration reaches the third
preset time period t3 (such
as 5 minutes). When the drain superheat degree DSH is greater than or equal to
the first preset value
Ml (such as A C) for the third preset time period t3, the timer is reset and
it is determined again
whether the drain superheat degree DSH satisfies the condition that the timer
starts timing.
According to an embodiment of the present disclosure, after the outdoor unit
is controlled to shut
down, it is further determined whether a number N of anti-liquid-slugging
protection activated by the
air conditioning system during a fourth preset time period t4 exceeds a preset
number (such as one).
While the number N of the anti-liquid-slugging protection activated by the air
conditioning system
during the fourth preset time period t4 exceeds the preset number (such as
one), the outdoor unit is
controlled to be unrecoverable without being powered off. While the number N
of the
anti-liquid-slugging protection activated by the air conditioning system
during the fourth preset time
period t4 does not exceed the preset number (such as one), the timer is reset,
and the outdoor unit is
controlled to restart after a fifth preset time period.
According to a specific embodiment of the present disclosure, the fourth
preset time period t4
may be 120 minutes and the fifth preset time period may be 6 minutes.
Specifically, the number N of the anti-liquid-slugging protection activated by
the air conditioning
system (that is, the number of controlling the outdoor unit to shut down) may
be counted by a counter.
While the number N of the anti-liquid-slugging protection activated by the air
conditioning system
during the fourth preset time period t4 (such as 120 minutes) exceeds the
preset number (such as one),
it is indicated that the suction superheat degree SSH of the air conditioning
system keeps continuously
relatively low, such that the outdoor unit is controlled to be unrecoverable
without being powered off.
That is, after the outdoor unit is powered off, the outdoor unit can be
recoverably started. While the
number N of the anti-liquid-slugging protection activated by the air
conditioning system during the
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fourth preset time period t4 (such as 120 minutes) does not exceed the preset
number (such as one),
the timer is reset and the outdoor unit is automatically controlled to restart
after the fifth preset time
period t5 (such as 6 minutes), and it is determined again whether the drain
superheat degree DSH
satisfies the condition that the timer starts timing.
As described above and illustrated in Fig. 4, the control method of anti-
liquid-slugging of air
conditioning system according to embodiments of the present disclosure may
specifically include the
following.
In block S101, the anti-liquid-slugging protection control is activated.
In block S102, the drain superheat degree DSH of the compressor is acquired in
real time and the
drain superheat degree DSH is monitored during the operating process of the
air conditioning system.
In block S103, it is determined whether the drain superheat degree DSH is less
than the first
preset value MI.
If yes, a block S104 is executed. If no, a block S105 is executed.
In block S104, it is determined whether a duration reaches the first preset
time period ti.
If yes, a block S106 is executed. If no, the block S103 is executed.
In block S105, the outdoor unit of the air conditioning system is controlled
to operate normally.
In block S106, the timer is controlled to start timing.
In block S107, it is determined whether the drain superheat degree DSH is
greater than or equal
to the first preset value MI.
If yes, a block S108 is executed. If no, a block S110 is executed.
In block S108, it is determined whether a duration reaches the third preset
time period t3.
If yes, a block S109 is executed. If no, the block S107 is executed.
In block S109, the timer is reset and the block S102 is executed.
In block S110, it is determined whether the counted time period t of the timer
reaches the second
preset time period t2.
If yes, a block S111 is executed. If no, the block S107 is executed.
In block S111, the outdoor unit of the air conditioning system is controlled
to shut down.
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In block S112, it is determined whether the number N of the anti-liquid-
slugging activated by the
air conditioning system during the fourth preset time period t4 exceeds the
preset number (such as
one).
If yes, a block S113 is executed. If no, a block S114 is executed.
In block S113, the outdoor unit is controlled to be unrecoverable without
being powered off.
In block S114, the timer is reset, and the outdoor unit is controlled to
restart after the fifth preset
time period t5, and the block S102 is executed.
In block S115, the anti-liquid-slugging control ends.
In conclusion, with the control method of anti-liquid-slugging of air
conditioning system
according to embodiments of the present disclosure, by acquiring the drain
superheat degree of the
compressor in real time, and by monitoring the drain superheat degree during
the operating process of
the air conditioning system, the timer is controlled to start timing when the
drain superheat degree is
less than the first preset value for the first preset time period; and the
outdoor unit of the air
conditioning system is controlled to shut down for preventing the compressor
from the liquid-slugging
when the counted time period of the timer reaches the second preset time
period. Therefore, the
control method of anti-liquid-slugging of air conditioning system according to
embodiments of the
present disclosure may realize anti-liquid-slugging protection by monitoring
the drain superheat
degree of the compressor in real time, such that it may be ensured that
refrigerant sucked back through
an air inlet of the compressor is gaseous, thereby preventing liquid
refrigerant from entering into the
compressor and avoiding the compressor being suffered from the liquid-
slugging. In addition, since
the value of the drain superheat degree is relatively large, which is easy for
data detection and
anti-liquid-slugging control, an accuracy of anti-liquid-slugging control is
improved and security and
reliability during the operating process of the air conditioning system are
improved.
Fig. 3 is a flow chart illustrating a control method of anti-liquid-slugging
of air conditioning
system according to another embodiment of the present disclosure. The air
conditioning system
includes the compressor, a condenser and an evaporator. As illustrated in Fig.
3, the control method of
anti-liquid-slugging of air conditioning system includes the followings.
In block S I, temperature Tc of an air outlet of the compressor is detected
and temperature T1 of a
middle part of the condenser and temperature T2 of a middle part of the
evaporator are detected.
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In block S2, when the air conditioning system is in a refrigerating mode, the
drain superheat
degree DSH of the compressor is calculated according to the temperature Tc of
the air outlet and the
temperature TI of the middle part of the condenser.
In block S3, when the air conditioning system is in a heating mode, the drain
superheat degree
DSH of the compressor is calculated according to the temperature Tc of the air
outlet and the
temperature T2 of the middle part of the evaporator.
Specifically, based on analysis of the operating process of the air
conditioning system, a pressure
vs enthalpy diagram illustrated in Fig. 2 may be obtained. In the diagram, a
longitudinal coordinate
represent a logarithm value LogP of an absolute pressure of the air
conditioning system, while a
horizontal coordinate represents a specific enthalpy value b of the air
conditioning system. As
illustrated in Fig. 2, the air conditioning system is in a superheat and
exothermic phase indicated by
segments 1-2, where gaseous refrigerant with high temperature and high
pressure is exhausted from
the air outlet of the compressor. The air conditioning system is in a constant
pressure and exothermic
phase indicated by segments 2-4. The air conditioning system is in a constant
pressure and
endothermic phase indicated by segments 5-6. The air conditioning system is in
a superheat and
endothermic phase indicated by segments 6-7, where the refrigerant is sucked
back through an air
inlet of the compressor. As illustrated in Fig. 2, the drain superheat degree
DSH of the air conditioning
system corresponds to the suction superheat degree SSH, and the value of the
drain superheat degree
DSH is greater than the value of the suction superheat degree SSH. Therefore,
when the drain
superheat degree DSH is within a predetermined range, it may be ensured that
the refrigerant sucked
back through the air inlet of the compressor is gaseous.
During the operating process of the air conditioning system, the temperature
Tc of the air outlet
of the compressor is detected in real time, and the temperature T1 of the
middle part of the condenser
and the temperature T2 of the middle part of the evaporator are detected. When
the air conditioning
system is in the refrigerating mode, the temperature T I of the middle part of
the condenser is
equivalent to saturation temperature at a high pressure side of the air
conditioning system. That is, the
temperature T1 of the middle part of the condenser may be determined as drain
saturation temperature.
Therefore, the drain superheat degree DSH of the compressor may be nearly
represented as a
difference (Tc-T I ) between the temperature Tc of the air outlet of the
compressor and the temperature
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T1 of the middle part of the condenser. When the air conditioning system is in
the heating mode, the
temperature T2 of the middle part of the evaporator is equivalent to the
saturation temperature at the
high pressure side of the air conditioning system. That is, the temperature T2
of the middle part of the
evaporator may be determined as the drain saturation temperature. Therefore,
the drain superheat
degree DSH of the compressor may be nearly represented as a difference (Tc-T2)
between the
temperature Tc of the air outlet of the compressor and the temperature T2 of
the middle part of the
evaporator. Further, the real-time drain superheat degree DSH may be used for
anti-liquid-slugging
control.
In block S4, the drain superheat degree DSH is monitored during the operating
process of the air
conditioning system.
In block S5, when the drain superheat degree DSH is less than a first preset
value MI for a first
preset time period tl, the timer is controlled to start timing. When a counted
time period t of the timer
reaches a second preset time period t2, an outdoor unit of the air
conditioning system is controlled to
shut down for preventing the compressor from liquid-slugging.
According to a specific embodiment of the present disclosure, the first preset
time period t I may
be 20 minutes, the second preset time period t2 may be 30 minutes and the
first preset value Ml may
be A C.
Specifically, the drain superheat degree DSH of the compressor is acquired in
real time, and the
drain superheat degree DSH is monitored during the operating process of the
air conditioning system
to determine whether the drain superheat degree DSH of the air conditioning
system is greater than or
equal to the first preset value Ml. When the drain superheat degree DSH is
greater than or equal to the
first preset value MI (such as A C), it is indicated that the suction
superheat degree SSH of the air
conditioning system is sufficiently large. The outdoor unit of the air
conditioning system keeps
operating normally and the refrigerant sucked back through the air inlet of
the compressor is gaseous.
When the drain superheat degree DSH is less than the first preset value Ml, it
is further determined
whether a duration reaches the first preset time period t 1 (such as 20
minutes). When the duration
reaches the first preset time period tl, the timer is controlled to start
timing.
Further, it is determined whether the counted time period t of the timer
reaches the second preset
time period t2 (such as 30 minutes). When the counted time period t of the
timer reaches the second
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preset time period t2, that is the duration when the drain superheat degree
DSH is less than the first
preset value Ml reaches the second preset time period t2, it is indicated that
the suction superheat
degree SSH of the air conditioning system is relatively low. Therefore, the
outdoor unit of the air
conditioning system is controlled to shut down for preventing liquid
refrigerant from being sucked
back through the air inlet of the compressor and avoiding the compressor being
suffered from the
liquid-slugging.
According to an embodiment of the present disclosure, during the timing
process of the timer,
when the drain superheat degree DSH is greater than or equal to the first
preset value MI for a third
preset time period t3, the timer is reset, and the control method continues to
determine whether the
drain superheat degree DSH satisfies a condition that the timer starts timing.
According to a specific embodiment of the present disclosure, the third preset
time period t3 may
be 5 minutes.
Specifically, during the timing process of the timer, the drain superheat
degree DSH is monitored
in real time. When the drain superheat degree DSH is greater than or equal to
the first preset value M1
(such as A C), it is further determined whether the duration reaches the third
preset time period t3
(such as 5 minutes). When the drain superheat degree DSH is greater than or
equal to the first preset
value MI (such as A C) for the third preset time period t3, the timer is reset
and it is determined again
whether the drain superheat degree DSH satisfies the condition that the timer
starts timing.
According to an embodiment of the present disclosure, after the outdoor unit
is controlled to shut
down, it is further determined whether a number N of anti-liquid-slugging
activated by the air
conditioning system during a fourth preset time period t4 exceeds a preset
number (such as one).
While the number N of the anti-liquid-slugging activated by the air
conditioning system during the
fourth preset time period t4 exceeds the preset number (such as one), the
outdoor unit is controlled to
be unrecoverable without being powered off. While the number N of the anti-
liquid-slugging activated
by the air conditioning system during the fourth preset time period t4 does
not exceed the preset
number (such as one), the timer is reset and the outdoor unit is controlled to
restart after a fifth preset
time period t5.
According to a specific embodiment of the present disclosure, the fourth
preset time period t4
may be 120 minutes, and the fifth preset time period t5 may be 6 minutes.
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Specifically, the number N of the anti-liquid-slugging activated by the air
conditioning system
(i.e., the number of controlling the outdoor unit to shut down) may be counted
via a counter. While the
number N of the anti-liquid-slugging activated by the air conditioning system
during the fourth preset
time period t4 (such as 120 minutes) exceeds the preset number (such as one),
it is indicated that the
suction superheat degree SSH of the air conditioning system keeps continuously
relatively low, such
that the outdoor unit is unrecoverable without being powered off. That is,
after the outdoor unit is
powered off, the outdoor unit can be recoverably started. While the number N
of the
anti-liquid-slugging activated by the air conditioning system during the
fourth preset time period t4
(such as 120 minutes) does not exceed the preset number (such as one), the
timer is reset and the
outdoor unit is automatically controlled to restart after the fifth preset
time period t5 (such as 6
minutes). In addition, it is determined again whether the drain superheat
degree DSH satisfies the
condition that the timer starts timing.
As described above and illustrated in Fig. 4, the control method of anti-
liquid-slugging of air
conditioning system according to embodiments of the present disclosure may
specifically include the
following.
In block S101, the anti-liquid-slugging protection control is activated.
In block S102, the drain superheat degree DSH of the compressor is acquired in
real time and the
drain superheat degree DS H is monitored during the operating process of the
air conditioning system.
In block S103, it is determined whether the drain superheat degree DSH is less
than the first
preset value MI.
If yes, a block S104 is executed. If no, a block S105 is executed.
In block S104, it is determined whether a duration reaches the first preset
time period tl.
If yes, a block S106 is executed. If no, the block S103 is executed.
In block S105, the outdoor unit of the air conditioning system is controlled
to operate normally.
In block S106, the timer is controlled to start timing.
In block S107, it is determined whether the drain superheat degree DSH is
greater than or equal
to the first preset value MI.
If yes, a block S108 is executed. If no, a block S110 is executed.
In block S108, it is determined whether a duration reaches the third preset
time period t3.
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If yes, a block S109 is executed, If no, the block S107 is executed.
In block S109, the timer is reset and the block S102 is executed.
In block S110, it is determined whether the counted time period t of the timer
reaches the second
preset time period t2.
If yes, a block Sill is executed. If no, the block S107 is executed.
In block S111, the outdoor unit of the air conditioning system is controlled
to shut down.
In block S112, it is determined whether the number N of the anti-liquid-
slugging activated by the
air conditioning system during the fourth preset time period t4 exceeds the
preset number (such as
one).
If yes, a block S113 is executed. If no, a block S114 is executed.
In block S113, the outdoor unit is controlled to be unrecoverable without
being powered off.
In block S114, the timer is reset, and the outdoor unit is controlled to
restart after the fifth preset
time period t5, and the block S102 is executed.
In block S115, the anti-liquid-slugging control ends.
In conclusion, with the control method of anti-liquid-slugging of air
conditioning system
according to embodiments of the present disclosure, by detecting the
temperature of the air outlet of
the compressor, and by detecting the temperature of the middle part of the
condenser and the
temperature of the middle part of the evaporator, when the air conditioning
system is in the
refrigerating mode, the drain superheat degree of the compressor is calculated
according to the
temperature of the air outlet and the temperature of the middle part of the
condenser, and when the air
conditioning system is in the heating mode, the drain superheat degree of the
compressor is calculated
according to the temperature of the air outlet and the temperature of the
middle part of the evaporator,
by monitoring the drain superheat degree during the operating process of the
air conditioning system,
the timer is controlled to start timing when the drain superheat degree is
less than the first preset value
for the first preset time period; and the outdoor unit of the air conditioning
system is controlled to shut
down for preventing the compressor from the liquid-slugging when the counted
time period of the
timer reaches the second preset time period. Therefore, the control method of
anti-liquid-slugging of
air conditioning system according to embodiments of the present disclosure may
realize
anti-liquid-slugging protection by monitoring the drain superheat degree of
the compressor in real
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time, such that it may be ensured that the refrigerant sucked back through an
air inlet of the
compressor is gaseous, thereby preventing liquid refrigerant from entering
into the compressor and
avoiding the compressor being suffered from the liquid-slugging. In addition,
since the value of the
drain superheat degree is relatively large, which is easy for data detection
and anti-liquid-slugging
control, an accuracy of anti-liquid-slugging control is improved and security
and reliability during the
operating process of the air conditioning system are improved.
Embodiments of the present disclosure further provide a non-transitory
computer readable
storage medium, having computer programs stored thereon. When the computer
programs are
executed by a processor, the control method of anti-liquid-slugging of air
conditioning system
according to embodiments of the present disclosure is realized.
Fig. 5 is a block diagram illustrating a control device of anti-liquid-
slugging of air conditioning
system according to an embodiment of the present disclosure. As illustrated in
Fig. 5, the control
device includes an acquiring module 10, a monitoring module 20 and a control
module 30. The
acquiring module 10 is configured to acquire a drain superheat degree DSH of a
compressor in real
time. The monitoring module 20 is configured to monitor the drain superheat
degree during an
operating process of the air conditioning system. The control module 30 is
configured to control a
timer 60 to start timing when the drain superheat degree is less than a first
preset value MI for a first
preset time period ti, and to control an outdoor unit of the air conditioning
system to shut down for
preventing the compressor from the liquid-slugging when a counted time period
of the timer 60
reaches a second preset time period t2.
According to a specific embodiment of the present disclosure, the first preset
time period ti may
be 20 minutes, the second preset time period t2 may be 30 minutes and the
first preset value M1 may
be A C.
Specifically, the acquiring module 10 is configured to acquire the drain
superheat degree DSH of
the compressor in real time, the monitoring module 20 is configured to monitor
the drain superheat
degree DSH during the operating process of the air conditioning system, and to
determine whether the
drain superheat degree DSH of the air conditioning system is greater than or
equal to the first preset
value MI. When the drain superheat degree DSH is greater than or equal to the
first preset value MI
(such as A C), it is indicated that a suction superheat degree SSH of the air
conditioning system is
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sufficiently large, such that the control module 30 controls the outdoor unit
of the air conditioning
system to keep operating normally. Refrigerant sucked back through an air
inlet of the compressor is
gaseous. When the drain superheat degree DSH is less than the first preset
value Ml, the control
module 30 is configured to further determine whether a duration reaches the
first preset time period tl
(such as 20 minutes). When the duration reaches the first preset time period
tl, the control module 30
is configured to control the timer 60 to start timing.
Further, the control module 30 is configured to determine whether a counted
time period t of the
timer 60 reaches the second preset time period t2 (such as 30 minutes). When
the counted time period
t of the timer 60 reaches the second preset time period t2, that is the
duration when the drain superheat
degree DSH is less than the first preset value M1 reaches the second preset
time period t2, the suction
superheat degree SSH of the air conditioning system is accordingly relatively
low, the control module
30 is configured to control the outdoor unit of the air conditioning system to
shut down for preventing
liquid refrigerant from being sucked back through the air inlet of the
compressor, and avoiding the
compressor being suffered from the liquid-slugging.
According to an embodiment of the present disclosure, as illustrated in Fig.
6, the control device
of anti-liquid-slugging of air conditioning system further includes a fourth
temperature sensor 40 and
a pressure sensor 50 arranged at the air outlet of the compressor. The fourth
temperature sensor 40 is
configured to detect temperature Tc of the air outlet of the compressor, and
the pressure sensor 50 is
configured to detect pressure P of the air outlet of the compressor. The
acquiring module 10 is
configured to calculate the drain superheat degree DSH of the compressor
according to the pressure P
of the air outlet and the temperature Tc of the air outlet.
According to a specific embodiment of the present disclosure, the fourth
temperature sensor 40
may be a drain temperature sensing bulb.
Based on analysis of the operating process of the air conditioning system, a
pressure vs enthalpy
diagram illustrated in Fig. 2 may be obtained. In the diagram, a longitudinal
coordinate represents a
logarithm value LogP of an absolute pressure of the air conditioning system,
while a horizontal
coordinate represents a specific enthalpy value b of the air conditioning
system. As illustrated in Fig. 2,
the air conditioning system is in a superheat and exothermic phase indicated
by segments 1-2, where
gaseous refrigerant with high temperature and high pressure is exhausted from
the air outlet of the
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compressor. The air conditioning system is in a constant pressure and
exothermic phase indicated by
segments 2-4. The air conditioning system is in a constant pressure and
endothermic phase indicated
by segments 5-6. The air conditioning system is in a superheat and endothermic
phase indicated by
segments 6-7, where the refrigerant is sucked back through the air inlet of
the compressor. As
illustrated in Fig. 2, the drain superheat degree DSH of the air conditioning
system corresponds to the
suction superheat degree SSH, and the value of the drain superheat degree DSH
is greater than the
value of the suction superheat degree SSH. Therefore, when the drain superheat
degree DSH is within
a predetermined range, it may be ensured that the refrigerant sucked back
through the air inlet of the
compressor is gaseous.
During the operating process of the air conditioning system, the pressure P of
the air outlet of the
compressor and the temperature Tc of the air outlet are detected in real time,
the acquiring module
may be configured to acquire drain saturation temperature Tp according to the
pressure P of the air
outlet of the compressor detected in real time, and to calculate a difference
between the temperature
Tc of the air outlet and the drain saturation temperature Tp as real-time
drain superheat degree DSH.
Therefore, the real-time drain superheat degree DSH may be used for anti-
liquid-slugging control.
According to an embodiment of present disclosure, during a timing process of
the timer 60, when
the drain superheat degree DSH is greater than or equal to the first preset
value Ml for a third preset
time period t3, the control module 30 is configured to reset the timer 60 and
continue to determine
whether the drain superheat degree DSH satisfies a condition that the timer 60
starts timing.
According to a specific embodiment of the present disclosure, the third preset
time period t3 may
be 5 minutes.
Specifically, during the timing process of the timer 60, the monitoring module
20 is configured to
monitor the drain superheat degree DSH in real time. When the drain superheat
degree DSH is greater
than or equal to the first preset value Ml (such as A C), the control module
30 is configured to further
determine whether a duration reaches the third preset time period t3 (such as
5 minutes). When the
drain superheat degree DSH is greater than or equal to the first preset value
Ml (such as A C) for the
third preset time period t3, the control module 30 is configured to reset the
timer 60 and determine
again whether the drain superheat degree DSH satisfies the condition that the
timer 60 starts timing.
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According to an embodiment of the present disclosure, after the outdoor unit
is controlled to shut
down, the control module 30 is configured to further determine whether a
number N of
anti-liquid-slugging activated by the air conditioning system during a fourth
preset time period t4
exceeds a preset number (such as one). While the number N of the anti-liquid-
slugging activated by
the air conditioning system during the fourth preset time period t4 exceeds
the preset number (such as
one), the control module 30 is configured to control the outdoor unit to be
unrecoverable without
being powered off. While the number N of the anti-liquid-slugging activated by
the air conditioning
system during the fourth preset time period t4 does not exceed the preset
number (such as one), the
control module 30 is configured to reset the timer 60 and control the outdoor
unit to restart after a fifth
preset time period t5.
According to a specific embodiment of the present disclosure, the fourth
preset time period t4
may be 120 minutes and the fifth preset time period t5 may be 6 minutes.
Specifically, the number N of the anti-liquid-slugging activated by the air
conditioning system
(i.e., the number of controlling the outdoor unit to shut down) may be counted
via a counter. While the
number N of the anti-liquid-slugging activated by the air conditioning system
during the fourth preset
time period t4 exceeds the preset number (such as one), it is indicated that
the suction superheat
degree SS H of the air conditioning system keeps continuously relatively low.
The control module 30
is configured to control the outdoor unit to be unrecoverable without being
powered off. That is,
after the outdoor unit is powered off, the outdoor unit can be recoverably
started. While the number N
of the anti-liquid-slugging activated by the air conditioning system during
the fourth preset time
period t4 (such as 120 minutes) does not exceed the preset number (such as
one), the control module
is configured to reset the timer and automatically control the outdoor unit to
restart after the fifth
preset time period t5 (such as 6 minutes), and determine again whether the
drain superheat degree
DSH satisfies the condition that the timer 60 starts timing.
25 In conclusion, according to the control device of anti-liquid-slugging
of air conditioning system
according to embodiments of the present disclosure, by acquiring the drain
superheat degree of the
compressor in real time with the acquiring module, and by monitoring the drain
superheat degree with
the monitoring module during the operating process of the air conditioning
system, the control module
is configured to control the timer to start timing when the drain superheat
degree is less than the first
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preset value for the first preset time period; and the control module is
configured to control the
outdoor unit of the air conditioning system to shut down for preventing the
compressor from the
liquid-slugging when the counted time period of the timer reaches the second
preset time period.
Therefore, the control device of anti-liquid-slugging of air conditioning
system according to
embodiments of the present disclosure may realize anti-liquid-slugging
protection by monitoring the
drain superheat degree of the compressor in real time, such that it may be
ensured that refrigerant
sucked back through an air inlet of the compressor is gaseous, thereby
preventing liquid refrigerant
from entering into the compressor and avoiding the compressor being suffered
from the
liquid-slugging. In addition, since the value of the drain superheat degree is
relatively large, which is
easy for data detection and anti-liquid-slugging control, an accuracy of anti-
liquid-slugging control is
improved and security and reliability during the operating process of the air
conditioning system are
improved.
Fig. 7 is a block diagram illustrating a control device of anti-liquid-
slugging of air conditioning
system according to another embodiment of the present disclosure. As
illustrated in Fig. 7, the control
device includes a first temperature sensor 70, a second temperature sensor 80,
a third temperature
sensor 90 and the acquiring module 10 (i.e., the calculating module 11 in
embodiments illustrated in
Fig. 7), the monitoring module 20 and the control module 30.
As illustrated in Fig. 8, the first temperature sensor 70 is arranged at the
air outlet of the
compressor 100. The first temperature sensor 70 is configured to detect
temperature Tc of the air
outlet of the compressor 10. The second temperature sensor 80 is arranged at a
middle part of the
evaporator 200, and the second temperature sensor 80 is configured to detect
temperature T1 of the
middle part of the evaporator 200. The third temperature sensor 90 is arranged
at a middle part of the
condenser 300, and the third temperature sensor 90 is configured to detect
temperature T2 of the
middle part of the condenser 300. The acquiring module 10 (i.e., the
calculating module 11) is
configured to, when the air conditioning system is in a refrigerating mode,
calculate the drain
superheat degree DS H of the compressor 100 according to the temperature Tc of
the air outlet and the
temperature T2 of the middle part of the condenser 300, and when the air
conditioning system is in a
heating mode, calculate the drain superheat degree DSH of the compressor 100
according to the
temperature Tc of the air outlet and the temperature T1 of the middle part of
the evaporator 200. The
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monitoring module 20 is configured to monitor the drain superheat degree DSH
during the operating
process of the air conditioning system. The control module 30 is configured to
control the timer 60 to
start timing when the drain superheat degree DSH is less than the first preset
value MI for the first
preset time period t I, and control the outdoor unit of the air conditioning
system to shut down for
preventing the compressor from the liquid-slugging when the counted time
period t of the timer 60
reaches the second preset time period t2.
According to a specific embodiment of the present disclosure, the first preset
time period tl may
be 20 minutes, the second preset time period t2 may be 30 minutes and the
first preset value MI may
be A C.,
Specifically, during the operating process of the air conditioning system, the
first temperature
sensor 70 is configured to detect the temperature Tc of the air outlet of
compressor 100 in real time,
the second temperature sensor 80 is configured to detect the temperature Ti of
the middle part of the
condenser 300 in real time, and the third temperature sensor 90 is configured
to detect the temperature
T2 of the evaporator 200 in real time. When the air conditioning system is in
the refrigerating mode,
the temperature T1 of the middle part of the condenser 300 is equivalent to
saturation temperature at a
high pressure side of the air conditioning system. That is, the temperature TI
of the middle part of the
condenser 300 may be determined as drain saturation temperature. Therefore,
the drain superheat
degree DSH of the compressor 100 may be nearly represented as a difference (Tc-
T1) between the
temperature Ic of the air outlet of the compressor 100 and the temperature Tl
of the middle part of the
condenser 300. When the air conditioning system is in the heating mode, the
temperature T2 of the
middle part of the evaporator 200 is equivalent to the saturation temperature
at the high pressure side
of the air conditioning system. That is, the temperature T2 of the middle part
of the evaporator 200
may be determined as the drain saturation temperature. The drain superheat
degree DSH of the
compressor 100 may be nearly represented as a difference (Tc-T2) between the
temperature Tc of the
air outlet of the compressor 100 and the temperature T2 of the middle part of
the evaporator 200. The
real-time drain superheat degree DSH may be used for anti-liquid-slugging
control.
As such, when the air conditioning system is in the refrigerating mode, the
calculating module 11
is configured to calculate the drain superheat degree DSH of the compressor
100 according to the
temperature Te o I the air outlet of the compressor 100 and the temperature TI
of the middle part of the
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condenser 300. When the air conditioning system is in the heating mode, the
calculating module 11 is
configured to calculate the drain superheat degree DSH of the compressor 100
according to the
temperature Tc of the air outlet of the compressor 100 and the temperature T2
of the middle part of the
evaporator 200. The monitoring module 20 is configured to monitor the drain
superheat degree DSH
during the operating process of the air conditioning system, and determine
whether the drain superheat
degree DSH of the air conditioning system is greater than or equal to the
first preset value MI. When
the drain superheat degree DSH is greater than or equal to the first preset
value M1 (such as A C), it is
indicated that the suction superheat degree DSH of the air conditioning system
is relatively large. The
control module 30 is configured to control the outdoor unit of the air
conditioning system to keep
operating normally. The refrigerant sucked back through the air inlet of the
compressor 100 is gaseous.
When the drain superheat degree DSH is less than the first preset value Ml,
the control module 30 is
configured to further determine whether a duration reaches the first preset
time period t 1 (such as 20
minutes). When the duration reaches the first preset time period t 1, the
control module 30 is
configured to control the timer 60 to start timing.
Further, the control module 30 is configured to determine whether the counted
time period t of
the timer 60 reaches the second preset time period t2 (such as 30 minutes).
When the counted time
period t of the timer 60 reaches the second preset time period t2, that is,
the duration when the drain
superheat degree DSH is less than the first preset value MI reaches the second
preset time period t2,
the suction superheat degree SSH of the air conditioning system is accordingly
relatively low, the
control module 30 is configured to control the outdoor unit of the air
conditioning system to shut
down for preventing liquid refrigerant from being sucked back through the air
inlet of the compressor
100 and avoiding the compressor 100 being suffered from the liquid-slugging.
According to an embodiment of the present disclosure, during the timing
process of the timer 60,
when the drain superheat degree DSH is greater than the first preset value M1
for the third preset time
period t3, the control module 30 is configured to reset the timer 60 and
continue to determine whether
the drain superheat degree DSH satisfies the condition that the timer 60
starts timing.
According to a specific embodiment of the present disclosure, the third preset
time period t3 may
be 5 minutes.
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Specifically, during the timing process of the timer 60, the monitoring module
20 is configured to
monitor the drain superheat degree DSH in real time. When the drain superheat
degree DSH is greater
than or equal to the first preset value MI (such as AC), the control module 30
may be configured to
further determine whether a duration reaches the third preset time period t3
(such as 5 minutes). When
the drain superheat degree DSH is greater than or equal to the first preset
value Ml (such as A C) for
the third preset time period t3, the control module 30 is configured to reset
the timer 60 and to
determine again whether the drain superheat degree DSH satisfies the condition
that the timer 60 starts
timing.
According to an embodiment of the present disclosure, after the outdoor unit
is controlled to shut
down, the control module 30 is further configured to determine whether a
number N of
anti-liquid-slugging activated by the air conditioning system during a fourth
preset time period t4
exceeds a preset number (such as two). While the number N of the anti-liquid-
slugging activated by
the air conditioning system during the fourth preset time period t4 exceeds
the preset number (such as
two), the control module 30 is configured to control the outdoor unit to be
unrecoverable without
being powered off While the number N of the anti-liquid-slugging activated by
the air conditioning
system during the fourth preset time period t4 does not exceed the preset
number (such as two), the
control module 30 is configured to reset the timer 60 and control the outdoor
unit to restart after a fifth
preset time period t5.
According to a specific embodiment of the present disclosure, the fourth
preset time period t4
may be 120 minutes, and the fifth preset time period t5 may be 6 minutes.
Specifically, the number N of the anti-liquid-slugging activated by the air
conditioning system
(that is the number of controlling the outdoor unit to shut down) may be
counted by a counter. While
the number N of the anti-liquid-slugging activated by the air conditioning
system during the fourth
preset time period t4 (such as 120 minutes) exceeds the preset number (such as
one), it is indicated
that the suction superheat degree SSH of the air conditioning system keeps
continuously relatively low.
The control module 30 is configured to control the outdoor unit to be
unrecoverable without being
powered off That is, it is required to power the outdoor unit off, and the
outdoor unit can be
recoverably started. While the number N of the anti-liquid-slugging activated
by the air conditioning
system during the fourth preset time period t4 (such as 120 minutes) does not
exceed the preset
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number (such as one), the control module 30 is configured to reset the timer
60 and automatically
control the outdoor unit to restart after the fifth preset time period t5
(such as 6 minutes), and
determine again whether the drain superheat degree DSH satisfies the condition
that the timer 60 starts
timing.
In conclusion, with the control device of anti-liquid-slugging of air
conditioning system
according to embodiments of the present disclosure, by detecting the
temperature of the air outlet of
the compressor with the first temperature sensor, by detecting the temperature
of the middle part of
the evaporator with the second temperature sensor and by detecting the
temperature of the middle part
of the condenser with the third temperature sensor, the drain superheat degree
of the compressor is
calculated via the calculating module according to the temperature of the air
outlet and the
temperature of the middle part of the condenser when the air conditioning
system is in the
refrigerating mode and the drain superheat degree of the compressor is
calculated via the calculating
module according to the temperature of the air outlet and the temperature of
the middle part of the
evaporator when the air conditioning system is in the heating mode. The
monitoring module 20 is
configured to monitor the drain superheat degree during the operating process
of the air conditioning
system. The control module is configured to control the timer to start timing
when the drain superheat
degree is less than the first preset value for the first preset time period,
and to control the outdoor unit
of the air conditioning system to shut down when the counted time period of
the timer reaches the
second preset time period. As can be seen above, the control device of anti-
liquid-slugging of air
conditioning system according to embodiments of the present disclosure may
realize
anti-liquid-slugging protection by monitoring the drain superheat degree of
the compressor in real
time, such that it may be ensured that the refrigerant sucked back through an
air inlet of the
compressor is gaseous, thereby preventing liquid refrigerant from entering
into the compressor and
avoiding the compressor being suffered from the liquid-slugging. In addition,
since the value of the
drain superheat degree is relatively large, which is easy for data detection
and anti-liquid-slugging
control, an accuracy of anti-liquid-slugging control is improved and security
and reliability during the
operating process of the air conditioning system are improved.
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Fig. 9 is a block diagram illustrating an air conditioning system according to
embodiments of the
present disclosure. As illustrated in Fig. 9, the air conditioning system 400
includes the
anti-liquid-slugging device 500 of the air conditioning system.
In conclusion, with the air conditioning system provided in embodiments of the
present
disclosure, an anti-liquid-slugging protection is realized by monitoring the
drain superheat degree of
the compressor in real time with the above control device of anti-liquid-
slugging of air conditioning
system, such that it may be ensured that the refrigerant sucked back through
an air inlet of the
compressor is gaseous, thereby preventing liquid refrigerant from entering
into the compressor and
avoiding the compressor being suffered from the liquid-slugging. In addition,
since the value of the
drain superheat degree is relatively large, which is easy for data detection
and anti-liquid-slugging
control, an accuracy of anti-liquid-slugging control is improved and security
and reliability during the
operating process of the air conditioning system are improved.
It is to be noted that, in the specification, relational terms such as "first"
and "second" are used
herein for distinguishing one entity or operation from another entity or
operation, but not necessarily
require or imply any such actual relationship or order existing among these
entities or operations.
Moreover, the terms "comprises", "includes" or any other variation thereof are
intended to cover a
non-exclusive inclusion, such that a process, method, article, or device
including a serious of elements
includes not only those elements, but also other elements that are not
explicitly listed, or includes
inherent elements of such the process, method, article, or device. Without
more limitation, there is no
exclusion that the process, the method, the article, or the device including
an element defined by the
sentence "include one... " includes other same elements.
The logic and/or steps described in other manners herein or shown in the flow
chart, for example,
may be considered as a particular sequence table of executable instructions
for realizing the logical
function, may be specifically achieved in any computer readable medium to be
used by the instruction
execution system, device or equipment (such as the system based on computers,
the system
comprising processors or other systems capable of obtaining the instruction
from the instruction
execution system, device and equipment and executing the instruction), or to
be used in combination
with the instruction execution system, device and equipment. As to the
specification, "the computer
readable medium" may be any device adaptive for including, storing,
communicating, propagating or
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transferring programs to be used by or in combination with the instruction
execution system, device or
equipment. More specific examples of the computer readable medium (non-
exhaustive list) comprise
but are not limited to: an electronic connection (an electronic device) with
one or more wires, a
portable computer enclosure (a magnetic device), a random access memory (RAM),
a read only
memory (ROM), an erasable programmable read-only memory (EPROM or a flash
memory), an
optical fiber device and a portable compact disk read-only memory (CDROM). In
addition, the
computer readable medium may even be a paper or other appropriate medium
capable of printing
programs thereon, this is because, for example, the paper or other appropriate
medium may be
optically scanned and then edited, decrypted or processed with other
appropriate methods when
necessary to obtain the programs in an electric manner, and then the programs
may be stored in the
computer memories.
It should be understood that each part of the present disclosure may be
realized by the hardware,
software, firmware or their combination. In the above embodiments, a plurality
of steps or methods
may be realized by the software or firmware stored in the memory and executed
by the appropriate
instruction execution system. For example, if it is realized by the hardware,
likewise in another
embodiment, the steps or methods may be realized by one or a combination of
the following
techniques known in the art: a discrete logic circuit having a logic gate
circuit for realizing a logic
function of a data signal, an application-specific integrated circuit having
an appropriate combination
logic gate circuit, a programmable gate array (PGA), a field programmable gate
array (FPGA), etc.
In the present disclosure, unless specified or limited otherwise, the terms
"mounted,"
"connected," "coupled," and "fixed" are used broadly and encompass such as
fixed, detachable or
integral connections; also can be mechanical or electrical connections, also
can be direct and indirect
connections via an intermediate medium, and further can be internal
connections or the interactions
between two elements, unless otherwise expressly defined which can be
understood by those skilled in
the art according to the detail embodiment of the present disclosure.
In the description of the present disclosure, reference throughout this
specification to "an
embodiment", "some embodiments", "an example", "a specific example" or "some
examples" means
that a particular feature, structure, material, or characteristic described in
connection with the
embodiment or example is included in at least one embodiment or example of the
present disclosure.
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The appearances of the phrases in various places throughout this specification
are not necessarily
referring to the same embodiment or example of the present disclosure.
Furthermore, the particular
features, structures, materials, or characteristics may be combined in any
suitable manner in one or
more embodiments or examples. Without a contradiction, the different
embodiments or examples and
the features of the different embodiments or examples can be combined by those
skilled in the art.
Although explanatory embodiments have been shown and described, it would be
appreciated that
the above embodiments cannot be construed to limit the present disclosure, and
changes,
modifications, alternatives, and variants can be made by those skilled in the
art within the scope of the
present disclosure.
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