CN107062550B - Control method of water chilling unit - Google Patents
Control method of water chilling unit Download PDFInfo
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- CN107062550B CN107062550B CN201710279889.5A CN201710279889A CN107062550B CN 107062550 B CN107062550 B CN 107062550B CN 201710279889 A CN201710279889 A CN 201710279889A CN 107062550 B CN107062550 B CN 107062550B
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 165
- 238000000034 method Methods 0.000 title claims abstract description 54
- 238000001816 cooling Methods 0.000 claims abstract description 145
- 238000005057 refrigeration Methods 0.000 claims description 23
- 230000008859 change Effects 0.000 claims description 20
- 230000008569 process Effects 0.000 claims description 19
- 230000010355 oscillation Effects 0.000 claims description 5
- 230000009467 reduction Effects 0.000 claims description 3
- 230000007704 transition Effects 0.000 claims description 2
- 230000000694 effects Effects 0.000 description 8
- 238000006243 chemical reaction Methods 0.000 description 7
- 239000003507 refrigerant Substances 0.000 description 6
- 238000001514 detection method Methods 0.000 description 4
- 230000005494 condensation Effects 0.000 description 3
- 238000009833 condensation Methods 0.000 description 3
- 238000004134 energy conservation Methods 0.000 description 3
- 238000001704 evaporation Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 239000000498 cooling water Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/70—Control systems characterised by their outputs; Constructional details thereof
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
-
- 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
- F24F11/72—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure
- F24F11/74—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity
- F24F11/77—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity by controlling the speed of ventilators
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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
- F24F2110/00—Control inputs relating to air properties
-
- 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
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/62—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
- F24F11/65—Electronic processing for selecting an operating mode
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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
- F24F2140/00—Control inputs relating to system states
- F24F2140/20—Heat-exchange fluid temperature
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
- Y02B30/70—Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
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- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Air Conditioning Control Device (AREA)
- Devices That Are Associated With Refrigeration Equipment (AREA)
Abstract
The invention discloses a control method of a water chilling unit, which is used when Tewo is more than TewodAnd starting the set at the time of + Td, and selecting an entering running mode: when Tao > TewodK1 and no compressor failure, the unit enters cooling mode; when Tao is reachedd≤Tao＜TewodK1 and no compressor failure, the unit enters cooling plus natural cooling mode; when Tao is less than or equal to Taod-K2 or compressor failure, the unit enters full free cooling mode; therefore, according to the control method of the water chilling unit, the relation among the outlet water temperature Tewo, the environment temperature Tao and the return difference temperature Td is judged, and the entering operation mode is selected, so that the control of the water chilling unit is more accurate, the water temperature fluctuation is smaller, the natural cooling is fully utilized, the requirements of users on the water temperature are met while the energy is saved, and the use experience of the users is improved.
Description
Technical Field
The invention belongs to the technical field of air conditioners, and particularly relates to a control method of a water chilling unit.
Background
The natural cooling mode is energy-saving and clean, and is widely applied to the air conditioner refrigeration technology, particularly to the air conditioner needing annual refrigeration, and the application is wider.
The air-cooled natural cooling unit who exists in the existing market mainly relies on single ambient temperature condition to select the operational mode, carries out the mode conversion, has the problem that control is not accurate, and also is not high to the utilization ratio in natural cooling water route, can not reach better energy-conserving effect.
Disclosure of Invention
The invention provides a control method of a water chilling unit, which is accurate in control and small in water temperature fluctuation.
In order to solve the technical problems, the invention adopts the following technical scheme:
a control method of a water chilling unit comprises a compressor, a condenser, a condensing fan, an evaporator, a natural cooling coil pipe arranged on one side of the condenser, a water inlet pipe and a water outlet pipe; the water inlet pipe is connected with a water inlet of the evaporator through a first control valve; the water inlet pipe is connected with the water inlet of the natural cooling coil pipe through a second control valve, and the water outlet of the natural cooling coil pipe is connected with the water inlet of the evaporator; the water outlet of the evaporator is connected with a water outlet pipe;
the control method comprises the following steps:
acquiring the outlet water temperature Tewo at the water outlet of the evaporator;
at Tewo > TewodAnd when + Td, starting the unit, selecting an operation mode:
when Tao > TewodK1 and compressor failure-free, the unit enters cooling mode: the first control valve is opened, the second control valve is closed, the compressor runs, and the fan runs;
when Tao is reachedd≤Tao＜TewodK1 and no compressor failure, the unit enters cooling plus natural cooling mode: closing a first control valve, opening a second control valve, operating a compressor and operating a fan;
when Tao is less than or equal to Taod-K2 or compressor failure, the unit enters full free cooling mode: closing a first control valve, opening a second control valve, stopping a compressor and operating a fan;
wherein, TewodIs a target temperature value, TaodFor the mode transition set point, Td is the return difference temperature, Tao is the ambient temperature, and K1 and K2 are constants greater than 0.
Further, when the operation mode is selected, the control method further includes:
if Tao is larger than or equal to a first set threshold value, the set time is continuously set, and the compressor has no fault, the unit enters a precooling mode: closing a first control valve, opening a second control valve, operating a compressor and operating a fan;
in the operation process of the precooling mode, if Tao is less than a second set threshold and the set time is continued, exiting the precooling mode and entering the refrigerating mode: the first control valve is opened, the second control valve is closed, the compressor runs, and the fan runs; wherein, Tewod-K1 < second set threshold < first set threshold.
Still further, during the operation of the cooling mode: if Taod≤Tao＜Tewod-K3, the operation mode is switched to the cooling plus natural cooling mode: closing a first control valve, opening a second control valve, operating a compressor and operating a fan; if Tewo < TewodTd, the unit is shut down; wherein K3 is a constant, and K3 > K1.
Still further, during the operation process of the refrigeration plus natural cooling mode:
if Tao is less than or equal to TaodK2 or compressor failure, the operating mode is switched to full free cooling mode: closing a first control valve, opening a second control valve, stopping a compressor and operating a fan;
if Tao > Tewod-K4, the operation mode is switched to the cooling mode: the first control valve is opened, the second control valve is closed, the compressor runs, and the fan runs;
if Tewo < TewodWhen Td is zero, the unit is shut down;
wherein K4 is a constant greater than 0, and K4 < K1.
Further, during full free cooling mode operation:
if Tao > Taod+ K5, the operation mode is switched to the cooling plus natural cooling mode: closing a first control valve, opening a second control valve, operating a compressor and operating a fan;
if Tewo < TewodWhen Td is zero, the unit is shut down; where K5 is a constant greater than 0.
Preferably, during the operation of the water chilling unit:
obtaining the exhaust pressure Pd of the compressor;
judging whether Pd is larger than or equal to a set exhaust pressure value;
if so, controlling the first control valve to be closed, the second control valve to be opened, the compressor to operate and the fan to operate.
Further, in the running process of the water chilling unit:
acquiring the exhaust pressure Pd and the suction pressure Ps of the compressor;
calculating an absolute pressure ratio Pr = Pd/Ps;
judging whether Pr is greater than or equal to a first set pressure ratio value;
if so, controlling the first control valve to be closed, the second control valve to be opened, the compressor to operate and the fan to operate.
Still further, the unit is in a completely natural cooling mode, according to Tewo and TewodAnd adjusting the rotating speed of the fan according to the difference value and the change trend of the Tewo.
Still further, the basis weights are Tewo and TewodThe difference and the trend of change of Tewo adjust the rotational speed of fan, specifically include:
(1) in Tewo-TewodWhen the temperature difference is more than or equal to the first set temperature difference, the rotating speed of the fan is increased;
(2) at a second set temperature difference < Tewo-TewodWhen the temperature is less than or equal to the first set temperature difference,
if the change trend of the Tewo is gradually reduced, the rotating speed of the fan is unchanged;
if the change trend of the Tewo is oscillation, the rotating speed of the fan is increased;
(3) at a third set temperature difference < Tewo-TewodWhen the temperature difference is less than or equal to the second set temperature difference, the rotating speed of the fan is unchanged;
(4) at a fourth set temperature difference < Tewo-TewodWhen the temperature difference is less than or equal to the third set temperature difference,
if the change trend of the Tewo is gradual reduction or oscillation, the rotating speed of the fan is reduced;
if the change trend of the Tewo is gradually increased, the rotating speed of the fan is unchanged;
(5) in Tewo-TewodAnd when the temperature difference is less than or equal to the fourth set temperature difference, the fan is stopped.
Furthermore, the unit adjusts the rotating speed of the fan according to the exhaust pressure Pd of the compressor in a refrigeration mode and a refrigeration plus natural cooling mode:
(1) when Pd is less than the first set pressure, the fan runs for a set time at a first set rotating speed, and then the fan is stopped;
(2) when the first set pressure is less than or equal to Pd and less than the second set pressure, the fan operates at a first set rotating speed;
(3) when the second set pressure is less than or equal to Pd and less than the third set pressure,
if Pr is larger than or equal to the second set pressure ratio, the rotating speed of the fan is unchanged;
if Pr is less than a second set pressure ratio, the rotating speed of the fan is reduced;
(4) when the third set pressure is less than or equal to Pd and less than the fourth set pressure,
if Pr is larger than or equal to the second set pressure ratio, the rotating speed of the fan is increased;
if Pr is smaller than the second set pressure ratio, the rotating speed of the fan is reduced until Pr is larger than or equal to the second set pressure ratio;
(5) when Pd is larger than or equal to the fourth set pressure, the fan operates at the maximum rotating speed;
wherein, the absolute pressure ratio Pr = compressor discharge pressure Pd/suction pressure Ps.
Compared with the prior art, the invention has the advantages and positive effects that: the control method of the water chilling unit is used when Tewo is more than TewodAnd starting the set at the time of + Td, and selecting an entering running mode: when Tao > TewodK1 and no compressor failure, the unit enters cooling mode; when Tao is reachedd≤Tao＜TewodK1 and no compressor failure, the unit enters cooling plus natural cooling mode; when Tao is less than or equal to Taod-K2 or compressor failure, the unit enters full free cooling mode; therefore, according to the control method of the water chilling unit, the relation among the outlet water temperature Tewo, the environment temperature Tao and the return difference temperature Td is judged, and the entering operation mode is selected, so that the control of the water chilling unit is more accurate, the water temperature fluctuation is smaller, the natural cooling is fully utilized, the requirements of users on the water temperature are met while the energy is saved, and the use experience of the users is improved.
Other features and advantages of the present invention will become more apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings.
Drawings
Fig. 1 is a schematic structural diagram of a chiller in a chiller control method according to the present invention;
FIG. 2 is a flow chart of one embodiment of a chiller control method according to the present invention;
FIG. 3 is a flow chart of the cooling mode of FIG. 2;
FIG. 4 is a flow chart of the cooling plus free cooling mode of FIG. 2;
fig. 5 is a flowchart of the free cooling mode of fig. 2.
Reference numerals:
1. a compressor; 2, a condenser; 3. a condensing fan; 4. an evaporator; 5. naturally cooling the coil pipe; 6. a water inlet pipe; 7. a water outlet pipe; v1, first control valve; v2 and a second control valve.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings and examples.
The embodiment provides a control method of a water chilling unit, wherein the water chilling unit mainly comprises a compressor 1, a condenser 2, a condensing fan 3, an evaporator 4, a natural cooling coil pipe 5 arranged on one side of the condenser 2, a water inlet pipe 6 and a water outlet pipe 7; the water inlet pipe 6 is connected with the water inlet of the evaporator 4 through a first control valve V1; the water inlet pipe 6 is connected with the water inlet of the natural cooling coil pipe 5 through a second control valve V2, and the water outlet of the natural cooling coil pipe 5 is connected with the water inlet of the evaporator 4; the water outlet of the evaporator 4 is connected with a water outlet pipe 7, as shown in fig. 1.
The first control valve V1 and the second control valve V2 may be implemented by a three-way valve. The natural cooling coil 5 and the condenser 2 are both fin heat exchangers and are V-shaped, and the natural cooling coil 5 is arranged on the outer side of the condenser 2.
The control method of the water chilling unit in the embodiment specifically includes the following steps, which are shown in fig. 2.
Step S1: and acquiring the outlet water temperature Tewo at the water outlet of the evaporator.
The outlet water temperature Tewo at this time is acquired under the conditions that the compressor is not started, the condensing fan is not started, V1 is turned on, and V2 is turned off.
Step S2: judging whether Tewo is more than Tewod+Td。
If yes, go to step S3: and starting the unit, and selecting an operation mode.
Tewo is the outlet water temperature of the evaporator, TewodIs a target temperature value, i.e. the temperature required by the user end, Td is the return difference temperature, Tewo > Tewod+ Td is a necessary condition for the start-up of the unit. Because the control purpose of the unit is that the outlet water temperature of the evaporator is Tewo = Tewod+ Td if Tewo is less than or equal to Tewod+ Td, then no start-up unit is required.
The return temperature Td (also called compensation temperature) is designed to compensate for temperature loss and meet the user's water temperature, because the water comes out from the evaporator and then reaches the user end through the outlet pipe and a section of pipeline where the water temperature is lost, for example, the user's desired water temperature TewodThe temperature is 12 ℃, if the water temperature Tewo after the water comes out of the evaporator is 12 ℃, the water temperature is lost by 2 ℃ in the pipeline, and the water temperature is 10 ℃ after the water passes through the pipeline and reaches a user end, so that the requirement of the user cannot be met, and the effect of the unit to be controlled cannot be achieved. Therefore, the return differential temperature Td is designed to compensate for the temperature loss in the pipeline and meet the user requirements.
Therefore, when the power-on command is received and Tewo > TewodAnd when the temperature reaches + Td, the unit is started, the ambient temperature Tao of the space where the water chilling unit is located is obtained, and the entering operation mode is selected.
Step S4: when Tao > TewodK1 and compressor failure-free, the unit enters cooling mode: the first control valve V1 is opened, the second control valve V2 is closed, the compressor is operated, and the fan is operated.
The specific process of starting the unit to enter the refrigeration mode is as follows: the start of the unit → 1s back → V1 is on, V2 is off → 180s back → water pump is on (water circulation starts) → 30s water flow detection → 90s back → compressor operation and fan operation. And 30s water flow detection is to prevent that the evaporation temperature at the refrigerant side of the evaporator is too low due to too small water flow after the water pump is started, so that the local water nest area at the water side of the unit evaporator is frozen to damage the evaporator.
Water in the water inlet pipe enters the evaporator through the V1, exchanges heat with refrigerant in the evaporator, reduces the water temperature, is discharged from the water outlet of the evaporator, is conveyed to a user side through the water outlet pipe, exchanges heat at the user side, then enters the water inlet pipe, and circulates in sequence.
In the embodiment, the rotating speed of the fan is adjusted according to the exhaust pressure Pd of the compressor, the capacity adjusting range is enlarged, the water temperature fluctuation is small, and the energy-saving effect is better.
Step S5: when Tao is reachedd≤Tao＜TewodK1 and no compressor failure, the unit enters cooling plus natural cooling mode: the first control valve V1 is closed, the second control valve V2 is opened, the compressor is operated, and the fan is operated.
The specific process that the unit starts to enter the refrigeration and natural cooling mode is as follows: the method comprises the steps of starting the unit → 1s later → closing the V1, starting the V2 → 180s later → opening the water pump (starting the water circulation) → 30s water flow detection → 90s later → operating the compressor and the fan.
Water in the water inlet pipe enters the natural cooling coil pipe 5 through the V2, the water temperature is reduced after heat exchange with air, the water enters the evaporator and exchanges heat with a refrigerant in the evaporator, the water temperature is further reduced, the load of a unit is reduced, and the energy-saving effect is achieved. The water channel exchanges heat with the evaporator through the natural cooling coil 5, so that the purposes of saving energy and reducing water temperature are achieved. The natural cooling provides part of cold energy, the rest cold energy is prepared by starting the compressor, the compressor can meet the cold energy requirement without full-speed operation, and the power of the compressor is not full-load power at the moment, so that the purposes of reducing consumption and saving energy are achieved.
In the embodiment, the rotating speed of the fan is adjusted according to the exhaust pressure Pd of the compressor, the capacity adjusting range is enlarged, the water temperature fluctuation is small, and the energy-saving effect is better.
Step S6: when Tao is less than or equal to Taod-K2 or compressor failure, the unit enters full free cooling mode: the first control valve V1 is closed, the second control valve V2 is opened, the compressor is stopped, and the fan is operated.
The specific process of starting the unit to enter the complete natural cooling mode is as follows: unit start → 1s back → V1 close, V2 open → 180s back → water pump open (waterway circulation start) → 30s water flow detection → 90s back → compressor not running, fan running.
Water in the water inlet pipe enters the natural cooling coil pipe 5 through the V2, the water temperature is reduced after heat exchange with air, the water enters the evaporator, is discharged from the water outlet of the evaporator and is conveyed to a user end through the water outlet pipe. The water channel completely exchanges heat through the natural cooling coil 5, and the purpose of energy conservation is achieved. Namely, the natural cooling of the natural cooling coil 5 can meet all the cold quantity requirements, the natural cooling is fully utilized, and the energy is saved and the consumption is reduced.
In the present embodiment, according to Tewo and TewodThe rotating speed of the fan is adjusted according to the difference value and the change trend of Tewo, the capacity adjusting range is enlarged, the water temperature fluctuation is small, and the energy-saving effect is better.
In this example, TaodThe value range is-5 to 10 for the mode conversion set value; tewodThe target temperature value is in a value range of 12-20; td is return difference temperature, and the value range is 2-5; k1 and K2 are both constants greater than 0.
The control method of the water chilling unit in the embodiment is that Tewo is more than TewodAnd starting the set at the time of + Td, and selecting an entering running mode: when Tao > TewodK1 and no compressor failure, the unit enters cooling mode; when Tao is reachedd≤Tao＜TewodK1 and no compressor failure, the unit enters cooling plus natural cooling mode; when Tao is less than or equal to Taod-K2 or compressor failure, the unit enters full free cooling mode; therefore, according to the control method of the water chilling unit, the entering operation mode is selected through the judgment of the relation among the outlet water temperature Tewo, the ambient temperature Tao and the return difference temperature Td, so that the control of the water chilling unit is more accurate, the water temperature fluctuation is smaller, the natural cooling is fully utilized, the requirements of a user on the water temperature are met while the energy is saved, and the use experience of the user is improved.
In the present embodiment, K1=3 and K2= 1. Namely:
when Tao > Tewod-3 and the compressor is not faulty, the unit enters the cooling mode;
when Tao is reachedd≤Tao＜Tewod-3 and the compressor is not in fault, entering a cooling plus natural cooling mode;
when Tao is less than or equal to Taod-1 or when the compressor is faulty, the unit enters a full free cooling mode.
In this embodiment, to avoid the high-voltage alarm, when the unit is started and the entering operation mode is selected, the control method further includes:
step S7: if Tao is larger than or equal to a first set threshold value and lasts for a set time (such as 10 minutes), and the compressor has no fault, the unit enters a precooling mode: the method comprises the following steps that a first control valve V1 is closed, a second control valve V2 is opened, a compressor runs, a fan runs, and the rotating speed of the fan is adjusted according to the exhaust pressure Pd of the compressor; the water route gets into natural cooling coil 5, reduces the air current temperature through natural cooling coil 5, and then reduces the condensation temperature, avoids the unit to appear high-pressure warning at high ring temperature, guarantees the normal operating of unit.
Step S8: in the operation process of the precooling mode, if Tao is less than a second set threshold and the set time is continued (for example, 10 minutes), exiting the precooling mode and entering the cooling mode: the first control valve V1 is opened, the second control valve V2 is closed, the compressor is operated, and the fan is operated.
In this embodiment, Tewod-K1 < second threshold < first threshold, e.g. 43 ℃ for the first threshold and 41 ℃ for the second threshold.
Through setting up the precooling mode, when ambient temperature Tao is higher (if be greater than 43 ℃), the water route gets into natural cooling coil 5, reduces the air current temperature through natural cooling coil 5, and then reduces condensing temperature, avoids the unit to appear high pressure warning under high ring temperature.
When the unit is in the normal operation process, the operation mode is switched according to the difference of the environmental temperature, so that the water outlet temperature of the evaporator is ensured, natural cooling is fully utilized, and the aim of saving energy is fulfilled.
Firstly, in the process of operating in the cooling mode, the specific steps of performing mode conversion according to the ambient temperature Tao are as follows, and are shown in fig. 3:
step S41: if Taod≤Tao＜Tewod-K3, the unit performs mode switching from the cooling mode to the cooling plus natural cooling mode: the first control valve V1 is closed, the second control valve V2 is opened, the compressor is operated, and the fan is operated. Water in the water inlet pipe enters the natural cooling coil pipe 5 through the V2, the water temperature is reduced after heat exchange with air, the water enters the evaporator and exchanges heat with a refrigerant in the evaporator, the water temperature is further reduced, the load of a unit is reduced, and the energy-saving effect is achieved.
Wherein K3 is a constant and K3 > K1, such as K1=3, K3= 5.
When the ambient temperature Tao changes, mode conversion is carried out, energy is saved, the water outlet temperature is ensured, and the fluctuation of the water outlet temperature is small.
In the present embodiment, it can be seen that the condition (Tao) for switching from the cooling mode to the cooling plus natural cooling moded≤Tao＜Tewod-K3) associated with the condition (Tao) of entering the cooling plus natural cooling mode at the start of the unitd≤Tao＜Tewod-K1) are different, K3 > K1 (e.g. K1=3, K3= 5), because when starting up, the ambient temperature Tao is slightly higher, which can ensure the unit to start up smoothly, avoiding low-voltage alarm; the ambient temperature Tao is slightly lower during the mode switching, so that the water temperature fluctuation is small during the mode switching.
Step S42: if Tewo < TewodTd, the unit is shut down.
At Tewo < TewodTd, which indicates that the indoor load at the user end is too low, and the indoor load does not rise very high for a short time without turning on the power supply, and therefore, the system is stopped for energy saving.
Secondly, in the operation process of the cooling and natural cooling mode, the specific steps of performing mode conversion according to the ambient temperature Tao are as follows, and are shown in fig. 4:
step S51: if Tao is less than or equal to Taod-K2, or if the compressor fails, the unit performs a mode change from the cooling plus free cooling mode to the full free cooling mode: the first control valve V1 is closed, the second control valve V2 is opened, the compressor is stopped, and the fan is operated. The water in the water inlet pipe enters natural cooling through V2The cooling coil pipe 5 is subjected to heat exchange with air, then the water temperature is reduced, and the water enters the evaporator, is discharged from a water outlet of the evaporator and is conveyed to a user side through a water outlet pipe. The water channel completely exchanges heat through the natural cooling coil 5, and the purpose of energy conservation is achieved.
After the unit is converted from a refrigeration and natural cooling mode to a complete natural cooling mode, the adjustment of the rotating speed of the fan is converted into the mode according to Tewo and TewodThe difference value and the change trend of the Tewo are adjusted; this is because the compressor has stopped running, the discharge pressure Pd gradually decreases, and if the rotation speed of the fan is continuously adjusted according to the discharge pressure Pd, the fan is decelerated and finally stopped.
Step S52: if Tao > Tewod-K4, the unit performs mode switching from the cooling plus natural cooling mode to the cooling mode: the first control valve V1 is opened, the second control valve V2 is closed, the compressor is operated, and the fan is operated. Water in the water inlet pipe enters the evaporator through the V1, exchanges heat with refrigerant in the evaporator, reduces the water temperature, is discharged from the water outlet of the evaporator, and is conveyed to a user side through the water outlet pipe.
Wherein K4 is a constant greater than 0, and K4 < K1, such as K1=3, K4=1, K2= 1.
In the present embodiment, it can be seen that the condition for switching from the cooling plus natural cooling mode to the cooling mode (Tao > Tewo)d-K4) associated with the condition for entering cooling mode at start-up of the unit (Tao > Tewo)d-K1), K4 < K1 (e.g. K1=3, K4= 1), the ambient temperature Tao required for the unit to start to enter the cooling mode is low, and the ambient temperature Tao required for the cooling plus natural cooling mode to switch to the cooling mode is high; the reason why the ambient temperature Tao is higher is that the refrigeration mode and the natural cooling mode are switched to the refrigeration mode is that the natural cooling capacity can be utilized as much as possible, and meanwhile, the ambient temperature Tao is higher, the exhaust pressure is high, and the compressor can be loaded faster.
Step S53: if Tewo < TewodTd, the unit is shut down.
Thirdly, in the process of operating in the complete natural cooling mode, the specific steps of performing mode conversion according to the ambient temperature Tao are as follows, as shown in fig. 5:
step S61: if Tao > Taod+ K5, the unit performs mode conversion from the complete natural cooling mode to the cooling plus natural cooling mode: the first control valve V1 is closed, the second control valve V2 is opened, the compressor is operated, and the fan is operated. Water in the water inlet pipe enters the natural cooling coil pipe 5 through the V2, the water temperature is reduced after heat exchange with air, the water enters the evaporator and exchanges heat with a refrigerant in the evaporator, the water temperature is further reduced, the load of a unit is reduced, and the energy-saving effect is achieved.
K5 is a constant greater than 0, such as K5= 4.
It can be seen that the condition for switching from the complete natural cooling mode to the cooling plus natural cooling mode (Tao > Tao)d+ K5), conditions for switching from cooling mode to cooling plus free cooling mode (Tao)d≤Tao＜Tewod-K3), conditions for entering cooling plus natural cooling mode (Tao) at set start-upd≤Tao＜Tewod-K1) all differ, Taod+K5＜Tewod-K3＜Tewod-K1, (K1 =3, K3=5, K5= 4); the required environment temperature Tao is highest when the compressor of the unit is started to enter a refrigeration and natural cooling mode, so that the evaporation temperature of the evaporator is higher when the compressor of the unit is started, and the compressor is easier to start while low-pressure alarm is avoided; the required environment temperature Tao is lowest when the complete natural cooling mode is converted into a refrigeration and natural cooling mode, and the water temperature fluctuation in the operation is ensured to be small; the required ambient temperature Tao when the refrigeration mode is switched to the refrigeration and natural cooling mode is between the two modes, and the purpose of ensuring that the water temperature fluctuation is small in operation is also achieved.
Step S62: if Tewo < TewodTd, the unit is shut down.
In this embodiment, in the running process of the water chilling unit, in order to avoid high-pressure alarm, the compressor discharge pressure Pd can be collected, and the running of the unit is controlled according to the size of Pd, which specifically includes: in the running process of the unit, obtaining the exhaust pressure Pd of the compressor, and judging whether Pd is more than or equal to a set exhaust pressure value; if yes, controlling the first control valve V1 to be closed, the second control valve V2 to be opened, the compressor to be operated and the fan to be operated, and adjusting the rotating speed of the fan according to Pd. The water route gets into natural cooling coil 5, reduces the air current temperature through natural cooling coil 5, and then reduces the condensation temperature, avoids the unit to appear high-pressure warning at high ring temperature.
In this embodiment, set up the exhaust pressure value and be 1.6, both avoided leading to the unit to damage because Pd is too big, avoided again because Pd undersize leads to the maloperation, influences the unit normal operating.
As another preferred design scheme of this embodiment, to avoid high-voltage alarm, the operation of the unit may be controlled according to the size of Pr, which specifically includes: in the running process of the water chilling unit, obtaining the exhaust pressure Pd and the suction pressure Ps of a compressor; calculating an absolute pressure ratio Pr = Pd/Ps, and judging whether Pr is greater than or equal to a first set pressure ratio; if yes, controlling the first control valve V1 to be closed, the second control valve V2 to be opened, the compressor to be operated and the fan to be operated, and adjusting the rotating speed of the fan according to Pd. The water route gets into natural cooling coil 5, reduces the air current temperature through natural cooling coil 5, and then reduces the condensation temperature, avoids the unit to appear high-pressure warning at high ring temperature.
In this embodiment, the first set pressure ratio is 4.8, which avoids the damage of the unit caused by too large Pr and avoids the misoperation and the influence on the normal operation of the unit caused by too small Pr.
In this embodiment, the rotation speed adjustment logic of the fan includes two types: one is in the complete natural cooling mode according to Tewo and TewodAnd secondly, in a refrigeration mode, a refrigeration plus natural cooling mode, the rotating speed of the fan is adjusted according to the exhaust pressure Pd of the compressor.
The fan is controlled by a direct current voltage signal of 0-10V, and the rotating speed of the fan is divided into 14 grades according to the voltage signal, which is as follows:
| fan gear | Output voltage V | Fan speed rpm |
| 0 | 0 | 0 |
| 1 | 1 | 135 |
| 2 | 1.5 | 185 |
| 3 | 2 | 230 |
| 4 | 2.5 | 275 |
| 5 | 3 | 320 |
| 6 | 3.5 | 373 |
| 7 | 4 | 430 |
| 8 | 4.5 | 485 |
| 9 | 5 | 550 |
| 10 | 6 | 634 |
| 11 | 7 | 740 |
| 12 | 8 | 850 |
| 13 | 9 | 960 |
| 14 | 10 | 1082 |
After the unit is started and enters a complete natural cooling mode according to Tewo and TewodThe difference and the change trend of Tewo adjust the fan rotational speed, specifically include:
(1) in Tewo-TewodAnd when the temperature difference is more than or equal to the first set temperature difference, the rotating speed of the fan is increased.
For example, the first set temperature difference is 2 ℃, and the fan speed is increased by 120s by one gear.
(2) At a second set temperature difference < Tewo-TewodWhen the temperature is less than or equal to the first set temperature difference,
if the change trend of Tewo is gradually reduced, namely the outlet water temperature is gradually reduced, the rotating speed of the fan is unchanged;
if the change trend of Tewo is oscillation, namely the water outlet temperature fluctuates up and down, the rotating speed of the fan is increased by one gear.
(3) At a third set temperature difference < Tewo-TewodWhen the temperature difference is less than or equal to the second set temperature difference, the rotating speed of the fan is unchanged.
(4) At a fourth set temperature difference < Tewo-TewodWhen the temperature difference is less than or equal to the third set temperature difference,
if the change trend of Tewo is gradually reduced or oscillated, namely the outlet water temperature is gradually reduced or fluctuates up and down, the rotating speed of the fan is reduced by one gear;
if the change trend of Tewo is gradually increased, namely the outlet water temperature is gradually increased, the rotating speed of the fan is unchanged.
(5) In Tewo-TewodAnd when the temperature difference is less than or equal to the fourth set temperature difference, the fan is stopped.
In this embodiment, the first set point temperature difference is 2 deg.C, the second set point temperature difference is 0 deg.C, the third set point temperature difference is-0.5 deg.C, and the fourth set point temperature difference is-2 deg.C.
Through the adjustment of the rotating speed of the fan, the fluctuation of the outlet water temperature of the evaporator is avoided, and the stability of the outlet water temperature is improved.
During the operation of the refrigeration mode and the refrigeration and natural cooling mode, and after the refrigeration and natural mode is converted into the complete natural mode, the rotating speed of the fan is adjusted according to the exhaust pressure Pd of the compressor, the fluctuation of the water outlet temperature is avoided, the stability of the water outlet temperature is improved, and the method specifically comprises the following steps:
(1) when Pd is less than the first set pressure, the fan runs for a set time at a first set rotating speed, and then the fan is stopped.
For example, the first set pressure is 0.35MPa, and the fan is operated at 1 st gear (e.g., 135 rpm) for 1 minute, and then stopped.
(2) When the first set pressure is less than or equal to Pd and less than the second set pressure, the fan operates at the first set rotating speed.
For example, the first set pressure is 0.35MPa, the second set pressure is 0.55MPa, and the fan speed is reduced by 20s for one step, and the fan speed is reduced to the first gear speed (e.g. 135 rpm) to operate at the first gear speed.
(3) When the second set pressure is less than or equal to Pd and less than the third set pressure,
if Pr is larger than or equal to the second set pressure ratio, the rotating speed of the fan is unchanged;
and if Pr is less than the second set pressure ratio, reducing the rotating speed of the fan by 20s by one gear.
(4) When the third set pressure is less than or equal to Pd and less than the fourth set pressure,
if Pr is larger than or equal to the second set pressure ratio, the rotating speed of the fan is increased by 20s for one gear;
if Pr is smaller than the second set pressure ratio, the rotating speed of the fan is reduced by one gear according to 20s until Pr is larger than or equal to the second set pressure ratio.
(5) When Pd is larger than or equal to the fourth set pressure, the rotating speed of the fan is immediately increased from the current rotating speed to the maximum rotating speed (such as 14 th gear, 1082 rpm) for operation.
Wherein, the absolute pressure ratio Pr = compressor discharge pressure Pd/suction pressure Ps.
In the present embodiment, the first set pressure is 0.35MPa, the second set pressure is 0.55MPa, the third set pressure is 0.85MPa, the fourth set pressure is 1.35MPa, and the second set pressure ratio is 1.9.
Through the adjustment of the rotating speed of the fan, the fluctuation of the outlet water temperature of the evaporator is avoided, and the stability of the outlet water temperature is improved.
According to the control method of the water chilling unit, when the unit is started, the entering operation mode is selected through judgment of the outlet water temperature Tewo, the ambient temperature Tao and the return difference temperature Td, so that the control of the unit is more accurate, and the requirement of a user on the water temperature is met while energy is saved; in the normal operation process of the unit, the operation mode is switched according to the ambient temperature Tao, so that the water outlet temperature of the evaporator is ensured, the fluctuation of the water outlet temperature is reduced, natural cooling is fully utilized, and the purposes of energy conservation and consumption reduction are achieved.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions.
Claims (10)
1. A control method of a water chilling unit comprises a compressor, a condenser, a condensing fan, an evaporator, a natural cooling coil pipe arranged on one side of the condenser, a water inlet pipe and a water outlet pipe;
the water inlet pipe is connected with a water inlet of the evaporator through a first control valve; the water inlet pipe is connected with the water inlet of the natural cooling coil pipe through a second control valve, and the water outlet of the natural cooling coil pipe is connected with the water inlet of the evaporator; the water outlet of the evaporator is connected with a water outlet pipe; the method is characterized in that:
the control method comprises the following steps:
acquiring the outlet water temperature Tewo at the water outlet of the evaporator;
at Tewo > TewodAnd when + Td, starting the unit, selecting an operation mode:
when Tao > TewodK1 and compressor failure-free, the unit enters cooling mode: the first control valve is opened, the second control valve is closed, the compressor runs, and the fan runs;
when Tao is reachedd≤Tao＜TewodK1 and no compressor failure, the unit enters cooling plus natural cooling mode: closing a first control valve, opening a second control valve, operating a compressor and operating a fan;
when Tao is less than or equal to Taod-K2 or compressor failure, the unit enters full free cooling mode: closing a first control valve, opening a second control valve, stopping a compressor and operating a fan;
wherein, TewodIs a target temperature value, TaodFor the mode transition set point, Td is the return difference temperature, Tao is the ambient temperature, and K1 and K2 are constants greater than 0.
2. The control method according to claim 1, characterized in that: when the operation mode is selected, the control method further includes:
if Tao is larger than or equal to a first set threshold value, the set time is continuously set, and the compressor has no fault, the unit enters a precooling mode: closing a first control valve, opening a second control valve, operating a compressor and operating a fan;
in the operation process of the precooling mode, if Tao is less than a second set threshold and the set time is continued, exiting the precooling mode and entering the refrigerating mode: the first control valve is opened, the second control valve is closed, the compressor runs, and the fan runs;
wherein, Tewod-K1 < second set threshold < first set threshold.
3. The control method according to claim 1, characterized in that: during the operation of the refrigeration mode:
if Taod≤Tao＜Tewod-K3, the operation mode is switched to the cooling plus natural cooling mode: closing a first control valve, opening a second control valve, operating a compressor and operating a fan;
if Tewo < TewodTd, the unit is shut down;
wherein K3 is a constant, and K3 > K1.
4. The control method according to claim 1, characterized in that: in the operation process of the refrigeration and natural cooling mode:
if Tao is less than or equal to TaodK2 or compressor failure, the operating mode is switched to full free cooling mode: closing a first control valve, opening a second control valve, stopping a compressor and operating a fan;
if Tao > Tewod-K4, the operation mode is switched to the cooling mode: the first control valve is opened, the second control valve is closed, the compressor runs, and the fan runs;
if Tewo < TewodWhen Td is zero, the unit is shut down;
wherein K4 is a constant greater than 0, and K4 < K1.
5. The control method according to claim 1, characterized in that: during full free cooling mode operation:
if Tao > Taod+ K5, the operation mode is switched to the cooling plus natural cooling mode: closing a first control valve, opening a second control valve, operating a compressor and operating a fan;
if Tewo < TewodWhen Td is zero, the unit is shut down;
where K5 is a constant greater than 0.
6. The control method according to claim 1, characterized in that: in the running process of the water chilling unit:
obtaining the exhaust pressure Pd of the compressor;
judging whether Pd is larger than or equal to a set exhaust pressure value;
if so, controlling the first control valve to be closed, the second control valve to be opened, the compressor to operate and the fan to operate.
7. The control method according to claim 1, characterized in that: in the running process of the water chilling unit:
acquiring the exhaust pressure Pd and the suction pressure Ps of the compressor;
calculating an absolute pressure ratio Pr = Pd/Ps;
judging whether Pr is greater than or equal to a first set pressure ratio value;
if so, controlling the first control valve to be closed, the second control valve to be opened, the compressor to operate and the fan to operate.
8. The control method according to claim 1, characterized in that: the units are in a completely natural cooling mode according to Tewo and TewodAnd adjusting the rotating speed of the fan according to the difference value and the change trend of the Tewo.
9. The control method according to claim 8, characterized in that: according to Tewo and TewodThe difference and the trend of change of Tewo adjust the rotational speed of fan, specifically include:
(1) in Tewo-TewodWhen the temperature difference is more than or equal to the first set temperature difference, the rotating speed of the fan is increased;
(2) at a second set temperature difference < Tewo-TewodWhen the temperature is less than or equal to the first set temperature difference,
if the change trend of the Tewo is gradually reduced, the rotating speed of the fan is unchanged;
if the change trend of the Tewo is oscillation, the rotating speed of the fan is increased;
(3) at a third set temperature difference < Tewo-TewodWhen the temperature difference is less than or equal to the second set temperature difference, the rotating speed of the fan is unchanged;
(4) at a fourth set temperature difference < Tewo-TewodWhen the temperature difference is less than or equal to the third set temperature difference,
if the change trend of the Tewo is gradual reduction or oscillation, the rotating speed of the fan is reduced;
if the change trend of the Tewo is gradually increased, the rotating speed of the fan is unchanged;
(5) in Tewo-TewodAnd when the temperature difference is less than or equal to the fourth set temperature difference, the fan is stopped.
10. The control method according to claim 1, characterized in that: the unit adjusts the rotating speed of a fan according to the exhaust pressure Pd of a compressor in a refrigeration mode and a refrigeration and natural cooling mode:
(1) when Pd is less than the first set pressure, the fan runs for a set time at a first set rotating speed, and then the fan is stopped;
(2) when the first set pressure is less than or equal to Pd and less than the second set pressure, the fan operates at a first set rotating speed;
(3) when the second set pressure is less than or equal to Pd and less than the third set pressure,
if Pr is larger than or equal to the second set pressure ratio, the rotating speed of the fan is unchanged;
if Pr is less than a second set pressure ratio, the rotating speed of the fan is reduced;
(4) when the third set pressure is less than or equal to Pd and less than the fourth set pressure,
if Pr is larger than or equal to the second set pressure ratio, the rotating speed of the fan is increased;
if Pr is smaller than the second set pressure ratio, the rotating speed of the fan is reduced until Pr is larger than or equal to the second set pressure ratio;
(5) when Pd is larger than or equal to the fourth set pressure, the fan operates at the maximum rotating speed;
wherein, the absolute pressure ratio Pr = compressor discharge pressure Pd/suction pressure Ps.
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| CN110736276B (en) * | 2019-10-21 | 2021-08-24 | 无锡职业技术学院 | Control method of natural cooling refrigeration system |
| CN110953778B (en) * | 2019-12-17 | 2021-06-29 | 重庆美的通用制冷设备有限公司 | Control method and system of refrigeration equipment, refrigeration equipment and readable storage medium |
| CN111536672B (en) * | 2020-04-10 | 2021-06-22 | 珠海格力电器股份有限公司 | Water chilling unit and control method thereof |
| CN111637611B (en) * | 2020-05-18 | 2021-12-07 | 珠海格力电器股份有限公司 | Water chilling unit control method and device, storage medium and water chilling unit |
| CN112178872B (en) * | 2020-09-18 | 2021-08-24 | 珠海格力电器股份有限公司 | Water chilling unit control method and device and water chilling unit |
| CN114136033A (en) * | 2021-11-25 | 2022-03-04 | 珠海格力电器股份有限公司 | Natural cooling system working mode switching method and system and natural cooling system |
| CN114198889B (en) * | 2021-12-17 | 2022-11-18 | 珠海格力电器股份有限公司 | Air-cooled chiller system, control method thereof, controller and storage medium |
| CN117128626B (en) * | 2023-07-21 | 2024-06-04 | 江森自控日立万宝空调(广州)有限公司 | Self-adaptive adjusting method for cooling mode of natural cooling air conditioning unit |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU909404A1 (en) * | 1976-07-09 | 1982-02-28 | Всесоюзный научно-исследовательский институт природных газов | System for cooling natural gas on main pipeline compressor station |
| CN102589114A (en) * | 2012-01-12 | 2012-07-18 | 广东申菱空调设备有限公司 | Air-cooled water chiller with natural cooling function and control method for water chiller |
| CN103900221A (en) * | 2014-03-03 | 2014-07-02 | 广东申菱空调设备有限公司 | Natural cooling control system and control method thereof |
| CN205678804U (en) * | 2016-06-08 | 2016-11-09 | 烟台顿汉布什工业有限公司 | A kind of cooling by wind with natural cooling function and air-conditioner |
| CN106440437A (en) * | 2016-11-24 | 2017-02-22 | 南京佳力图机房环境技术股份有限公司 | Novel natural cooling resource refrigerating system and control method thereof |
| CN106440431A (en) * | 2016-09-13 | 2017-02-22 | 克莱门特捷联制冷设备(上海)有限公司 | Refrigerating system of cooling unit |
-
2017
- 2017-04-26 CN CN201710279889.5A patent/CN107062550B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU909404A1 (en) * | 1976-07-09 | 1982-02-28 | Всесоюзный научно-исследовательский институт природных газов | System for cooling natural gas on main pipeline compressor station |
| CN102589114A (en) * | 2012-01-12 | 2012-07-18 | 广东申菱空调设备有限公司 | Air-cooled water chiller with natural cooling function and control method for water chiller |
| CN103900221A (en) * | 2014-03-03 | 2014-07-02 | 广东申菱空调设备有限公司 | Natural cooling control system and control method thereof |
| CN205678804U (en) * | 2016-06-08 | 2016-11-09 | 烟台顿汉布什工业有限公司 | A kind of cooling by wind with natural cooling function and air-conditioner |
| CN106440431A (en) * | 2016-09-13 | 2017-02-22 | 克莱门特捷联制冷设备(上海)有限公司 | Refrigerating system of cooling unit |
| CN106440437A (en) * | 2016-11-24 | 2017-02-22 | 南京佳力图机房环境技术股份有限公司 | Novel natural cooling resource refrigerating system and control method thereof |
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Effective date of registration: 20201116 Address after: 266101 Haier Industrial Park, Haier Road, Laoshan District, Shandong, Qingdao, China Patentee after: QINGDAO HAIER AIR-CONDITIONING ELECTRONIC Co.,Ltd. Patentee after: Haier Smart Home Co., Ltd. Address before: 266101 Haier Industrial Park, Haier Road, Laoshan District, Shandong, Qingdao, China Patentee before: QINGDAO HAIER AIR-CONDITIONING ELECTRONIC Co.,Ltd. |