CN117006560B - Water-cooling integrated water chilling unit with natural cooling function and control method - Google Patents

Water-cooling integrated water chilling unit with natural cooling function and control method Download PDF

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CN117006560B
CN117006560B CN202311011731.1A CN202311011731A CN117006560B CN 117006560 B CN117006560 B CN 117006560B CN 202311011731 A CN202311011731 A CN 202311011731A CN 117006560 B CN117006560 B CN 117006560B
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cooling
water
temperature
low
cooling water
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CN117006560A (en
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章立标
王红燕
倪焕军
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Zhejiang King Co ltd
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Zhejiang King Co ltd
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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
    • F24F5/00—Air-conditioning systems or apparatus not covered by F24F1/00 or F24F3/00, e.g. using solar heat or combined with household units such as an oven or water heater
    • F24F5/0046—Air-conditioning systems or apparatus not covered by F24F1/00 or F24F3/00, e.g. using solar heat or combined with household units such as an oven or water heater using natural energy, e.g. solar energy, energy from the ground
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/30—Control or safety arrangements for purposes related to the operation of the system, e.g. for safety or monitoring
    • F24F11/46—Improving electric energy efficiency or saving
    • 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
    • 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F5/00—Air-conditioning systems or apparatus not covered by F24F1/00 or F24F3/00, e.g. using solar heat or combined with household units such as an oven or water heater
    • F24F5/0007—Air-conditioning systems or apparatus not covered by F24F1/00 or F24F3/00, e.g. using solar heat or combined with household units such as an oven or water heater cooling apparatus specially adapted for use in air-conditioning
    • F24F5/001—Compression cycle type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/20—Disposition of valves, e.g. of on-off valves or flow control valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/30—Expansion means; Dispositions thereof
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/40—Fluid line arrangements

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Combustion & Propulsion (AREA)
  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Thermal Sciences (AREA)
  • Sustainable Development (AREA)
  • Signal Processing (AREA)
  • Sustainable Energy (AREA)
  • Fuzzy Systems (AREA)
  • Mathematical Physics (AREA)
  • Other Air-Conditioning Systems (AREA)

Abstract

The application relates to the technical field of air conditioners, in particular to a water-cooling integrated water chilling unit with a natural cooling function and a control method. The water cooling integrated water chilling unit integrates the modules, is convenient to install and maintain, and is functionally equivalent to an integrated air conditioning cold collection station; the distance between the condenser and the cooling tower as well as between the condenser and the cooling water pump is short, the resistance of the cooling water system is small, and the power consumption of the cooling water pump can be saved by about 33%; the unit does not need to start a compressor in winter, and can directly utilize the low temperature of the outdoor air to realize cooling of chilled water, so that the refrigerating energy efficiency of the unit is obviously improved; the water-cooling integrated water chilling unit is directly arranged outdoors, a special air conditioner room is omitted, and the construction cost can be further reduced.

Description

Water-cooling integrated water chilling unit with natural cooling function and control method
Technical Field
The application relates to the technical field of air conditioners, in particular to a water-cooling integrated water chilling unit with a natural cooling function and a control method.
Background
The traditional water cooling chiller unit must be provided with a special air conditioner room, and the cooling water pump has higher lift and power consumption because the cooling tower is far away from the chiller unit and the cooling water pipeline is longer. Meanwhile, in actual engineering projects, a chilled water pump, a cooling water pump and a cooling tower are often excessively configured, so that the energy consumption of an air conditioning system is high.
Because the water chiller, the chilled water pump, the cooling water pump and the cooling tower are purchased from different equipment manufacturers, a centralized control system is absent. The air conditioning system is in a partial load operation state 99% of the time, and when the compressor of the water chilling unit is unloaded or stopped, the chilled water pump, the cooling water pump and the cooling tower are still in a full load operation state, so that the operation efficiency of the air conditioning system is low. According to actual measurement statistics of a large number of air conditioning engineering projects, the sum of the power of the chilled water pump, the cooling water pump and the cooling tower only accounts for about 16% of the installed capacity of the whole air conditioning system, but the actual running energy consumption accounts for about 45%, and therefore the integration and linkage control between the water chilling unit and the chilled water pump, and between the cooling water pump and the cooling tower are extremely important.
The process water cooling and cooling water units in the industries of data centers, medicines, chemical engineering, rubber, photovoltaics and the like often need refrigeration operation all year round so as to meet the requirements of production process parameters. When the outdoor air temperature is lower, the high pressure and condensation temperature of the unit can be reduced, and the pressure difference between the front and the rear of the throttle valve is too small, so that the circulation capacity of the throttle valve and the liquid supply amount to the evaporator are greatly reduced, and finally the refrigerating capacity and the refrigerating energy efficiency of the unit are seriously attenuated. Meanwhile, when the pressure difference between the high pressure and the low pressure of the compressor is too low, the oil supply circulation quantity of the compressor is insufficient, the lubrication condition of the bearing is deteriorated, the loading speed is too slow, and the operation reliability of the compressor is seriously affected.
The cooling water outlet temperature of the condenser is generally increased by reducing the flow rate of cooling water in winter, so that the condensation temperature of the unit is kept above 30 ℃, the circulation capacity of a throttle valve and the minimum oil supply pressure difference required by oil supply in the compressor are maintained, and the refrigerating energy efficiency of the unit is low and the running power consumption is high. At this time, the outdoor air temperature may be far lower than the chilled water temperature, and if the chilled water can be directly cooled by utilizing the low-temperature characteristic of the outdoor air, the operation energy consumption of the unit can be greatly reduced.
Disclosure of Invention
Aiming at the technical problems that a compressor of a water cooling main machine of a traditional water cooling air conditioning system is poor in linkage with a chilled water pump, a cooling water pump and a cooling tower, the resistance of the cooling water system is high, the power consumption of the cooling water pump is high, the compressor still needs to operate when the outdoor air temperature is far lower than the chilled water temperature, the operation power consumption of a unit is high, the cold energy contained in the outdoor low-temperature air cannot be utilized, and the like, the application discloses a water cooling integrated water chilling unit with a natural cooling function and a control method.
On one hand, the application provides a water-cooling integrated water chilling unit with a natural cooling function, which comprises a water-cooling water chilling unit module 5, a freezing hydraulic power module 12, a natural cooling heat exchanger module 13, a cooling heat rejection module 19 and a centralized controller module 15 for sending control instructions to the modules; the water-cooling chiller module 5 comprises a compressor 1, a water-cooling condenser 2, a throttling device 3 and an evaporator 4 which are sequentially connected and form a circulation loop; the freezing hydraulic module 12 comprises a freezing water filter 8, a freezing water pump 9, a first control valve 10 and a second control valve 14, wherein the outlet of the freezing water pump 9 is respectively connected with the freezing water inlets of the first control valve 10 and the second control valve 14 through a freezing water pipe 6, the freezing water outlet of the first control valve 10 is respectively connected with the freezing water inlet of the evaporator 4 and the freezing water outlet of the natural cooling heat exchanger module 13 through the freezing water pipe 6, and the freezing water outlet of the second control valve 14 is connected with the freezing water inlet of the natural cooling heat exchanger module 13 through the freezing water pipe 6; the cooling heat rejection module 19 comprises a third control valve 16, a cooling water pump 17 and a cooling tower 18, wherein an inlet of the cooling water pump 17 is connected with a cooling water outlet positioned at the bottom of the cooling tower 18 through a cooling water pipe 7, the third control valve 16 controls cooling water at an outlet of the cooling water pump 17 to flow to the water-cooled condenser 2 and/or the natural cooling heat exchanger module 13, and the cooling water outlet of the water-cooled condenser 2 and the cooling water outlet of the natural cooling heat exchanger module 13 are connected to a top water inlet of the cooling tower 18 through the cooling water pipe 7; the freezing water outlet of the freezing water pump 9, the freezing water inlet and the freezing water outlet of the evaporator 4, the cooling water inlet and the cooling water outlet of the natural cooling heat exchanger module 13, the cooling water outlet of the water cooling condenser 2 and the air inlet side of the cooling tower 18 are all provided with temperature sensors; the centralized controller module 15 controls the fans of the compressor 1, the chilled water pump 9, the cooling water pump 17, and the cooling tower 18, the first control valve 10, the second control valve 14, the third control valve 16, and the throttle device 3 based on the data acquired by the sensors.
In particular, the compressor 1 is selected from screw compressors, scroll compressors, centrifugal compressors or other types of compressors.
In particular, the throttling device 3 is selected from a thermostatic expansion valve, an electronic expansion valve, an electric butterfly valve or other type of throttling element.
In particular, the first control valve 10 and the second control valve 14 are selected from a switch type electric two-way valve or a proportional type electric two-way valve, so as to realize that the chilled water output by the chilled water pump 9 in different operation modes directly enters the evaporator 4 or firstly enters the natural cooling heat exchanger module 13 and then enters the evaporator 4; or the freezing hydraulic module 12 further comprises an expansion tank 11.
In particular, the third control valve 16 is an electric three-way valve or two electric two-way valves respectively leading to the water-cooled condenser 2 and the natural cooling heat exchanger module 13, so as to control the flow distribution ratio of the cooling water delivered by the cooling water pump 17 between the natural cooling heat exchanger module 13 and the water-cooled condenser 2.
In particular, the cooling tower 18 is selected from an open cooling tower, a closed cooling tower, or other types of cooling towers.
On the other hand, the application also provides a control method of the water-cooling integrated water chilling unit with the natural cooling function, as described above, the centralized controller module 15 controls the operation mode of the unit according to the difference between the inlet wet bulb temperature t WB of the cooling tower and the total frozen outlet water temperature target value t W3S, and the unit comprises a mechanical refrigeration mode, a natural cooling precooling+mechanical refrigeration recooling mode and a natural cooling mode.
In particular, in the mechanical refrigeration mode, at t WB≥tW3S-Δt1, Δt 1 is-3 ℃ to 9 ℃, preferably 3 ℃, the compressor 1 is operated, the first control valve 10 is powered on, the second control valve 14 is powered off, and the cooling water pump 17 and the cooling tower 18 are in an operating state; chilled water entering the unit passes through a chilled water filter 8, is sequentially conveyed to a first control valve 10 and an evaporator 4 by a chilled water pump 9, and exchanges heat with low-temperature low-pressure refrigerant which is relatively low in temperature and flows from a throttling device 3 in the evaporator 4; the low-temperature low-pressure gas refrigerant coming out of the evaporator 4 enters the compressor 1, is compressed into high-temperature high-pressure gas, then enters the water-cooled condenser 2, discharges a large amount of heat released in the condensation process to the cooling water to heat the cooling water, and is condensed into high-pressure liquid; then, the high-pressure liquid refrigerant enters a throttling device 3, throttled and depressurized into low-temperature low-pressure refrigerant, then enters an evaporator 4, absorbs the relatively high-temperature chilled water heat to cool the low-pressure refrigerant, evaporates into low-pressure gas, and then returns to the compressor 1 again to be compressed into high-temperature high-pressure gas, so that the high-pressure refrigerant is repeatedly circulated; the cooling water absorbs condensation heat discharged by the high-temperature high-pressure refrigerant in the water-cooling condenser 2, then the temperature rises, the cooling water is led to the cooling tower 18 from a cooling water outlet of the water-cooling condenser 2 through the cooling water pipe 7, the cooling water temperature is reduced after the heat is discharged to outdoor air in the cooling tower 18, and then the cooling water is conveyed to the third control valve 16 by the cooling water pump 17 and then enters the water-cooling condenser 2, and the circulation is repeated; the unit centralized controller module 15 controls the running number and the running frequency of fans of the cooling tower 18 according to the cooling water outlet temperature t W6 of the water-cooled condenser 2, and when t W6＜tW6S is carried out, t W6S is the lowest cooling water outlet temperature, the range is 20-30 ℃, preferably 25 ℃, and the running number and the running frequency of the fans of the cooling tower 18 are gradually reduced; if the condition t W6＜tW6S is still satisfied when only 1 fan is operating at the lowest frequency, the flow distribution proportion of the cooling water is controlled by the third control valve 16, so that the flow rate of the cooling water entering the water-cooled condenser 2 is gradually reduced, that is, the flow rate of the cooling water entering the natural cooling heat exchanger module 13 is gradually increased until t W6≥tW6S.
In particular, the unit is in a natural cooling precooling+mechanical refrigeration recooling mode, when t W3S-Δt2＜tWB＜tW3S-Δt1, deltat 1 is-3-9 ℃, preferably 3 ℃, deltat 2 is 4-16 ℃, preferably 8 ℃, the compressor 1 is operated, the first control valve 10 is powered off, the second control valve 14 is powered on, and the cooling water pump 17 and the fan of the cooling tower 18 are in an operating state; the low-temperature cooling water cooled by the cooling tower 18 is conveyed to the third control valve 16 by the cooling water pump 17 and is split into two paths, wherein one path enters the water-cooling condenser 2 to absorb the condensation heat of the high-temperature high-pressure gas refrigerant, and the other path enters the natural cooling heat exchanger module 13 to precool the chilled water with relatively high temperature; the chilled water entering the unit is conveyed to a second control valve 14 by a chilled water pump 9 after passing through a chilled water filter 8, then enters a natural cooling heat exchanger module 13 through a chilled water pipe 6, exchanges heat with low-temperature cooling water flowing from a cooling tower and having relatively low temperature in the natural cooling heat exchanger module 13, releases heat to the low-temperature cooling water, the temperature of the chilled water is reduced after the low-temperature cooling water is precooled by the low-temperature cooling water, the chilled water continuously flows to an evaporator 4 through the chilled water pipe 6, and after the heat temperature of the chilled water absorbed by the low-temperature cooling water in the natural cooling heat exchanger module 13 is increased, the low-temperature cooling water continuously flows to a water inlet of a cooling tower 18 through a cooling water pipe 7; the low-temperature low-pressure gas refrigerant from the evaporator 4 enters the compressor 1, is compressed into high-temperature high-pressure gas, enters the water-cooled condenser 2, discharges a large amount of heat released in the condensation process to low-temperature cooling water to heat the low-temperature cooling water, and is condensed into high-pressure liquid; then, the high-pressure liquid refrigerant enters a throttling device 3, is throttled and depressurized into low-temperature low-pressure refrigerant, then enters an evaporator 4, absorbs the heat of the chilled water precooled by low-temperature cooling water, cools the chilled water again, evaporates into low-pressure gas, and then returns to the compressor 1 again to be compressed into high-temperature high-pressure gas, and thus the circulation is repeated; the chilled water temperature after being cooled again by the low-temperature low-pressure refrigerant is reduced to within the allowable deviation e of the target value t W3S, wherein e is 0.3-3 ℃, preferably 0.5 ℃, and then leaves the unit from the chilled water outlet of the evaporator 4; cooling water heated by high-temperature high-pressure refrigerant in the water-cooled condenser 2 and cooling water heated by chilled water in the natural cooling heat exchanger module 13 are collected by the cooling water pipe 7 and then led to a water inlet of the cooling tower 18, heat is discharged to outdoor air in the cooling tower 18, the cooling water temperature is reduced, and then the cooling water is respectively conveyed to the water-cooled condenser 2 and the natural cooling heat exchanger module 13 by the cooling water pump 17 through the third control valve 16; when the unit operates in the natural cooling precooling and mechanical refrigeration sub-cooling mode, all fans of the cooling tower 18 and the cooling water pump 17 are in the highest frequency, the lower the inlet air wet bulb temperature t WB of the cooling tower is, the lower the cooling inlet water temperature t W4 of the natural cooling heat exchanger module 13 is correspondingly, the larger the heat exchange temperature difference and the heat exchange quantity between low-temperature cooling water and freezing water in the natural cooling heat exchanger module 13 is, namely the larger the precooling quantity of the freezing water by the low-temperature cooling water is, the lower the freezing inlet water temperature t W2 of the evaporator 4 is, the smaller the deviation from the freezing total outlet water temperature target value t W3S is, therefore, the smaller the refrigeration load of the water-cooling chiller module 5 and the running power consumption of the compressor 1 are, the higher the refrigerating energy efficiency of the unit is; the unit centralized controller module 15 controls the operation capacity of the compressor 1 according to the deviation value of the total frozen water outlet temperature t W3 and the target value t W3S, and when t W3＜tW3S -e, the compressor 1 is unloaded; when t W3＞tW3S +e, loading the compressor 1; when t W3S-e≤tW3≤tW3S +e, the operating capacity of the compressor 1 remains unchanged; the unit centralized controller module 15 controls the flow distribution proportion of cooling water through the third control valve 16 according to the cooling water outlet temperature t W6 of the water-cooled condenser 2, and the lower the air inlet wet bulb temperature t WB of the cooling tower is, the lower the water outlet temperature of the cooling tower 18 is, namely the lower the cooling water inlet temperature t W4 of the natural cooling heat exchanger module 13 is, the lower the cooling water outlet temperature t W6 of the water-cooled condenser 2 is; at t W6＜tW6S, the flow of cooling water into the water-cooled condenser 2 is gradually reduced, i.e. the flow of cooling water into the free-cooling heat exchanger module 13 is gradually increased, until t W6≥tW6S. At this time, as the flow rate of the cooling water entering the natural cooling heat exchanger module 13 increases, the heat exchange amount between the low-temperature cooling water and the chilled water in the natural cooling heat exchanger module 13 increases, that is, the precooling capacity of the low-temperature cooling water to the chilled water increases, thereby reducing the chilled water inlet temperature t W2 of the evaporator 4, finally reducing the refrigeration load of the water cooling water machine module 5 and the operation power consumption of the compressor 1, and improving the refrigeration energy efficiency of the unit.
In particular, in the natural cooling mode, when t WB≤tW3S-Δt2, Δt 2 is 4 ℃ to 16 ℃, preferably 8 ℃, the compressor 1 is stopped, the first control valve 10 is powered off, the second control valve 14 is powered on, the cooling water pump 17 and the cooling tower 18 are in an operating state, the low-temperature cooling water cooled by the cooling tower 18 is delivered to the third control valve 16 by the cooling water pump 17, and then all or part of the cooling water flow enters the natural cooling heat exchanger module 13 through the third control valve 16 to cool the chilled water with relatively high temperature; chilled water entering the unit is conveyed to a second control valve 14 by a chilled water pump 9 after passing through a chilled water filter 8, then enters a natural cooling heat exchanger module 13 by a chilled water pipe 6, exchanges heat with low-temperature cooling water flowing from a cooling tower and having relatively low temperature in the natural cooling heat exchanger module 13, and the temperature of the chilled water cooled by the low-temperature cooling water is directly reduced to be within the allowable deviation e of a target value t W3S of the total chilled water temperature, wherein e is 0.3-3 ℃, preferably 0.5 ℃; meanwhile, the temperature of the low-temperature cooling water is increased after the low-temperature cooling water absorbs the heat of the chilled water in the natural cooling heat exchanger module 13, then the low-temperature cooling water flows to the water inlet of the cooling tower 18 through the cooling water pipe 7, the temperature of the cooling water is reduced after the heat is discharged to the outdoor low-temperature air in the cooling tower 18, and then the cooling water is conveyed to the natural cooling heat exchanger module 13 again through the third control valve 16 by the cooling water pump 17, and the circulation is repeated; the unit centralized controller module 15 controls the running number and running frequency of the cooling tower fans according to the deviation of the total frozen water outlet temperature t W3 and the target value t W3S thereof, and the total frozen water outlet temperature t W3 is equal to the water inlet temperature t W2 of the evaporator; when t W3＜tW3S -e is carried out, the operation number and the operation frequency of each fan of the cooling tower 18 are gradually reduced, so that the cooling capacity of outdoor air in the cooling tower 18 to cooling water is reduced, the cooling inlet temperature t W4 of the natural cooling heat exchanger module 13 is improved, the heat exchange temperature difference and the heat exchange quantity between low-temperature cooling water and chilled water in the natural cooling heat exchanger module 13 are further reduced, and the total chilled outlet water temperature t W3 is improved; when only 1 fan is in the lowest frequency operation and still meets the condition t W3＜tW3S -e, part of low-temperature cooling water is bypassed to flow to the water-cooled condenser 2 so as to reduce the flow rate of the low-temperature cooling water entering the natural cooling heat exchanger module 13, reduce the heat exchange amount between the low-temperature cooling water and the chilled water in the natural cooling heat exchanger module 13, namely reduce the cooling capacity of the low-temperature cooling water on the chilled water, thereby improving the total chilled water temperature t W3 and controlling the deviation between the total chilled water temperature t W3 and the target value t W3S within the allowable deviation e; when t W3＞tW3S +e, gradually increasing the flow of low-temperature cooling water entering the natural cooling heat exchanger module 13 to improve the heat exchange amount between the low-temperature cooling water and the chilled water in the natural cooling heat exchanger module 13, namely improving the cooling capacity of the low-temperature cooling water to the chilled water, thereby reducing the total chilled water outlet temperature t W3 and controlling the deviation between the total chilled water outlet temperature t W3 and the target value t W3S within the allowable deviation e; after all low-temperature cooling water conveyed by the cooling water pump 17 flows to the natural cooling heat exchanger module 13, if the condition of t W3＞tW3S +e is still met, the running number and running frequency of each fan of the cooling tower 18 are gradually increased so as to improve the cooling capacity of outdoor low-temperature air in the cooling tower 18 to the cooling water, reduce the cooling water inlet temperature t W4 of the natural cooling heat exchanger module 13 and further improve the heat exchange temperature difference and heat exchange quantity between the low-temperature cooling water and the chilled water in the natural cooling heat exchanger module 13, thereby reducing the total chilled water outlet temperature t W3; controlling the deviation of the target value t W3S from the target value t W3S within the allowable deviation e; when t W3S-e≤tW3≤tW3S +e, the running number and running frequency of fans of the cooling tower 18 are kept unchanged, and meanwhile, the opening degrees from the interface a of the third control valve 16 to the interface b and the interface c are kept unchanged.
On the basis of the common sense in the art, the above preferred conditions can be arbitrarily combined to obtain the preferred examples of the application.
The technical scheme has the following advantages or beneficial effects: the water cooling integrated water chilling unit integrates the water chilling unit, the cooling tower, the cooling water pump, the hydraulic module, the centralized control system and other equipment, the distance between the condenser of the water chilling unit and the cooling tower as well as between the condenser of the water chilling unit and the cooling water pump is short, the resistance of the cooling water system is small, and the power consumption of the cooling water pump can be saved by about 33%. Meanwhile, according to the energy-saving optimization control strategy, the on-off states, the running capacities and the running frequencies of compressors, chilled water pumps, cooling tower fans, and the on-off states and the running parameters of each electric two-way valve and each electric three-way valve under different outdoor air temperatures, chilled water temperature running working conditions and different air conditioner loading conditions can be intelligently controlled, the annual refrigerating energy efficiency of the unit is improved to the maximum extent, the system integration level is high, the system is functionally equivalent to an integral air conditioner cold collecting station, the installation, the running and the maintenance are convenient, and a special air conditioner room is not needed. In winter, the unit can directly utilize the low-temperature characteristic of the outdoor air to realize cooling of chilled water, and the compressor is not required to be started, so that the operation energy consumption can be greatly reduced, and the refrigeration energy efficiency of the unit is obviously improved. The water-cooling integrated water chilling unit is directly arranged outdoors, a special air conditioner room is omitted, and the construction cost can be further reduced. Of course, not all of the advantages described above are necessarily achieved at the same time by any one of the solutions of the application.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It will be obvious to a person skilled in the art that other figures can be obtained from the figures provided without the inventive effort.
Fig. 1 is a schematic structural diagram of a water-cooling integrated chiller with a natural cooling function according to an embodiment of the present application.
Fig. 2 is a schematic diagram illustrating connection control of a centralized controller of a water-cooling integrated chiller with a natural cooling function according to an embodiment of the present application.
Wherein, 1-compressor; 2-a water-cooled condenser; 3-a throttle device; 4-an evaporator; 5-a water-cooling chiller module; 6-freezing water pipe; 7-cooling water pipes; 8-chilled water filter; 9-a chilled water pump; 10-a first control valve; 11-an expansion tank; 12-a freezing hydraulic module; 13-naturally cooling the heat exchanger module; 14-a second control valve; 15-a centralized controller module; 16-a third control valve; 17-a cooling water pump; 18-a cooling tower; 19-cooling the heat rejection module.
Detailed Description
The technical solutions in the embodiments of the present application are clearly and completely described below with reference to the accompanying drawings. It is obvious that the described embodiments are only some of the embodiments of the present application and are intended to explain the inventive concept. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to fall within the scope of the application.
The terms "first," "second," and the like, as used in the description, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. The term "plurality" means two or more, unless specifically defined otherwise.
The terms "coupled," "connected," and the like as used in the description herein are to be construed broadly and may be, for example, fixedly coupled, detachably coupled, or integrally formed, unless otherwise specifically defined and limited; may be a mechanical connection, an electrical connection; can be directly connected and indirectly connected through an intermediate medium; may be a communication between two elements or an interaction between two elements. The specific meaning of the terms in the embodiments can be understood by those of ordinary skill in the art according to the specific circumstances.
The terms "one particular embodiment" and "one particular embodiment" as used in this description mean 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 application. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.
Referring to fig. 1, a water-cooling integrated chiller with a natural cooling function is provided in an embodiment of the present application, which includes a water-cooling chiller module 5, a cooling heat rejection module 19, a freezing hydraulic module 12, a natural cooling heat exchanger module 13, and a centralized controller module 15 for sending control instructions to the above modules, where the water-cooling integrated chiller integrates the above modules into a whole, and the system integration is high, and is functionally completely equivalent to an integral air-conditioning cold-collecting station, so as to facilitate installation and maintenance. The water-cooling integrated water chilling unit is directly installed outdoors, thereby saving a special air conditioner room and further reducing the construction cost. The low temperature characteristic of the outdoor air can be directly utilized to cool the chilled water in winter, a compressor is not required to be started, the operation energy consumption can be greatly reduced, and the refrigeration energy efficiency of the unit is obviously improved.
The water-cooling chiller module 5 comprises a compressor 1, a water-cooling condenser 2, a throttling device 3 and an evaporator 4 which are sequentially connected and form a circulation loop. The compressor 1 may be a screw compressor, a scroll compressor or a centrifugal compressor, or other types of compressors. The throttling device 3 can adopt a thermal expansion valve, an electronic expansion valve or an electric butterfly valve, and other types of throttling valves.
The chilled water power module 12 includes a chilled water filter 8, an expansion tank 11, a chilled water pump 9, a first control valve 10, and a second control valve 14. The outlet of the chilled water pump 9 is respectively connected with the chilled water inlets of the first control valve 10 and the second control valve 14 through the chilled water pipe 6; the freezing water outlet of the first control valve 10 is respectively connected with the freezing water inlet of the evaporator 4 and the freezing water outlet of the natural cooling heat exchanger module 13 through the freezing water pipe 6, and the freezing water outlet of the second control valve 14 is connected with the freezing water inlet of the natural cooling heat exchanger module 13 through the freezing water pipe 6. The first control valve 10 and the second control valve 14 can adopt a switch type electric two-way valve or a proportional type electric two-way valve, so that chilled water output by the chilled water pump 9 in different operation modes directly enters the evaporator 4 or enters the natural cooling heat exchanger module 13 first and then enters the evaporator 4.
The cooling heat rejection module 19 comprises a third control valve 16, a cooling water pump 17, a cooling tower 18. The third control valve 16 may be an electric three-way valve or two electric two-way valves leading to the water-cooled condenser 2 and the natural cooling heat exchanger module 13, respectively, to control the flow distribution ratio of the cooling water delivered by the cooling water pump 17 between the natural cooling heat exchanger module 13 and the water-cooled condenser 2. The cooling tower 18 may be an open cooling tower, a closed cooling tower, or other types of cooling towers.
Taking the electric three-way valve as an example of the third control valve 16, the inlet of the cooling water pump 17 is connected with the cooling water outlet at the bottom of the cooling tower 18 through the cooling water pipe 7, the interface a of the third control valve 16 is connected with the outlet of the cooling water pump 17 through the cooling water pipe 7, the interface c of the third control valve 16 is connected with the cooling water inlet of the water-cooled condenser 2 through the cooling water pipe 7, and the interface b of the third control valve 16 is connected with the cooling water inlet of the natural cooling heat exchanger module 13 through the cooling water pipe 7. The cooling water outlet of the water-cooled condenser 2 and the cooling water outlet of the natural cooling heat exchanger module 13 are connected to the top water inlet of the cooling tower 18 through the cooling water pipe 7.
The freezing water outlet of the freezing water pump 9 is provided with a temperature sensor, and the detected temperature is the total freezing water inlet temperature t W1. The freezing water inlet and the freezing water outlet of the evaporator 4 are respectively provided with a temperature sensor, and the detected temperatures are the freezing water inlet temperature t W2 and the freezing total water outlet temperature t W3 of the evaporator 4 respectively. The cooling water inlet and the cooling water outlet of the natural cooling heat exchanger module 13 are respectively provided with temperature sensors, and the detected temperatures are the cooling water inlet temperature t W4 and the cooling water outlet temperature t W5 of the natural cooling heat exchanger module 13. The cooling water outlet of the water-cooled condenser 2 is provided with a temperature sensor, and the detected temperature is the cooling water outlet temperature t W6 of the water-cooled condenser 2. The air inlet side of the cooling tower 18 is provided with a dry bulb temperature sensor and a wet bulb temperature sensor, and the detected temperatures are respectively the air inlet dry bulb temperature t DB and the air inlet wet bulb temperature t WB of the cooling tower 18.
When the deviation of the frozen total water outlet temperature t W3 from the target value t W3S is less than or equal to e, the e is 0.3-3 ℃, preferably 0.5 ℃, and the unit centralized controller module 15 controls the frozen water flow and the running frequency of the frozen water pump according to the temperature difference between the frozen total water inlet temperature t W1 and the frozen total water outlet temperature t W3. When the load at the tail end of the air conditioner is lower, and the temperature difference between the total freezing water inlet temperature t W1 and the total freezing water outlet temperature t W3 is smaller than the set value a, wherein a is 3-10 ℃, preferably 7 ℃, the unit centralized controller module 15 controls the operation frequency of the chilled water pump 9 to be reduced so as to reduce the flow rate of chilled water, and the temperature difference between the total freezing water inlet temperature t W1 and the total freezing water outlet temperature t W3 is improved, so that the operation power consumption of the chilled water pump 9 is reduced. Conversely, when the end load of the air conditioner is higher, and the temperature difference between the total freezing water inlet temperature t W1 and the total freezing water outlet temperature t W3 is larger than the set value a, the unit centralized controller module 15 controls the operation frequency of the chilled water pump 9 to be increased so as to increase the flow rate of chilled water and reduce the temperature difference between the total freezing water inlet temperature t W1 and the total freezing water outlet temperature t W3, so that the air conditioner load is adapted to the increase of the air conditioner load.
The unit centralized controller module 15 controls the operation modes of the unit according to the difference between the inlet wet bulb temperature t WB of the cooling tower and the target value t W3S of the total frozen outlet water temperature, and the unit has three operation modes of mechanical refrigeration, natural cooling precooling, mechanical refrigeration recooling and natural cooling.
The first mode, mechanical refrigeration mode. At t WB≥tW3S-Δt1, Δt 1 is-3 ℃ to 9 ℃, preferably 3 ℃, the compressor 1 is operated, the first control valve 10 is powered on, the second control valve 14 is powered off, and the cooling water pump 17 and the cooling tower 18 are in operation. Chilled water entering the unit passes through a chilled water filter 8 and is then sequentially delivered by a chilled water pump 9 to a first control valve 10 and an evaporator 4, where the evaporator 4 exchanges heat with a relatively low temperature, low pressure refrigerant flowing from a restriction 3.
The low-temperature low-pressure gas refrigerant coming out of the evaporator 4 enters the compressor 1, is compressed into high-temperature high-pressure gas, then enters the water-cooled condenser 2, discharges a large amount of heat released in the condensation process to the cooling water to heat the cooling water, and is condensed into high-pressure liquid; then, the high-pressure liquid refrigerant enters the throttling device 3, throttled and depressurized into low-temperature low-pressure refrigerant, then enters the evaporator 4, absorbs the relatively high-temperature chilled water heat to cool the low-pressure refrigerant, evaporates into low-pressure gas, and then returns to the compressor 1 again to be compressed into high-temperature high-pressure gas, and thus the high-pressure refrigerant is repeatedly circulated.
The cooling water absorbs the condensation heat discharged by the high-temperature high-pressure refrigerant in the water-cooled condenser 2, then the temperature of the cooling water rises, the cooling water is led to the cooling tower 18 from the cooling water outlet of the water-cooled condenser 2 through the cooling water pipe 7, the cooling water temperature is reduced after the heat is discharged to the outdoor air in the cooling tower 18, and then the cooling water is conveyed to the third control valve 16 by the cooling water pump 17 and then enters the water-cooled condenser 2, and the circulation is repeated.
The unit centralized controller module 15 controls the operation number and the operation frequency of fans of the cooling tower 18 according to the cooling outlet water temperature t W6 of the water-cooled condenser 2. When t W6＜tW6S,tW6S is the lowest cooling water outlet temperature, the range is 20-30 ℃, preferably 25 ℃, the running number and the running frequency of fans of the cooling tower 18 are gradually reduced; if the condition t W6＜tW6S is still satisfied when only 1 fan is operating at the lowest frequency, the flow distribution proportion of the cooling water is controlled by the third control valve 16, the opening degree of the interface a to the interface c of the third control valve 16 is gradually reduced, and the opening degree of the interface a to the interface b is increased, so that the flow rate of the cooling water entering the water-cooled condenser 2 is reduced until t W6≥tW6S, and in the process, the flow rate of the cooling water from the interface a of the third control valve 16 to the natural cooling heat exchanger module 13 is gradually increased.
And in the second mode, the natural cooling precooling and mechanical refrigeration recooling modes are adopted. At t W3S-Δt2＜tWB＜tW3S-Δt1, Δt 2 is 4 ℃ to 16 ℃, preferably 8 ℃, the compressor 1 is operated, the first control valve 10 is powered off, the second control valve 14 is powered on, and the cooling water pump 17 and the cooling tower 18 are in operation. The low-temperature cooling water cooled by the cooling tower 18 is delivered to the third control valve 16 by the cooling water pump 17, and is split into two paths, wherein one path enters the water-cooled condenser 2 from the interface c of the third control valve 16 to absorb the condensation heat of the high-temperature high-pressure gas refrigerant, and the other path enters the natural cooling heat exchanger module 13 from the interface b of the third control valve 16 to precool the chilled water with relatively high temperature.
Chilled water entering the unit is conveyed to a second control valve 14 by a chilled water pump 9 after passing through a chilled water filter 8, then enters a natural cooling heat exchanger module 13 through a chilled water pipe 6, exchanges heat with low-temperature cooling water flowing from a cooling tower and having relatively low temperature in the natural cooling heat exchanger module 13, releases heat to the low-temperature cooling water, and after the low-temperature cooling water is precooled, the temperature of the chilled water is reduced, and then the chilled water continuously flows to the evaporator 4 through the chilled water pipe 6. At the same time, after the temperature of the low-temperature cooling water is increased by absorbing the heat of the chilled water in the natural cooling heat exchanger module 13, the low-temperature cooling water continuously flows to the water inlet of the cooling tower 18 through the cooling water pipe 7.
The low-temperature low-pressure gas refrigerant from the evaporator 4 enters the compressor 1, is compressed into high-temperature high-pressure gas, enters the water-cooled condenser 2, discharges a large amount of heat released in the condensation process to low-temperature cooling water to heat the low-temperature cooling water, and is condensed into high-pressure liquid; then, the high-pressure liquid refrigerant enters the throttling device 3, throttled and depressurized into low-temperature low-pressure refrigerant, then enters the evaporator 4, absorbs the heat of the chilled water precooled by the low-temperature cooling water, cools the chilled water again, evaporates into low-pressure gas, and then returns to the compressor 1 again to be compressed into high-temperature high-pressure gas, and the cycle is repeated. The chilled water temperature after being cooled again by the low temperature low pressure refrigerant falls within the allowable deviation e of the target value t W3S, and then leaves the unit from the chilled water outlet of the evaporator 4. The cooling water heated by the high-temperature and high-pressure refrigerant in the water-cooled condenser 2 increases in temperature, and then passes from the cooling water outlet of the water-cooled condenser 2 to the water inlet of the cooling tower 18 via the cooling water pipe 7.
The cooling water heated by the high-pressure refrigerant in the water-cooled condenser 2 and the cooling water heated by the chilled water in the natural cooling heat exchanger module 13 are collected by the cooling water pipe 7 and led to the cooling tower 18, the cooling water temperature is reduced after the heat is discharged to the outdoor air in the cooling tower 18, and then the cooling water is respectively conveyed to the water-cooled condenser 2 and the natural cooling heat exchanger module 13 by the cooling water pump 17 through the third control valve 16.
When the unit is operated in the natural cooling precooling plus mechanical refrigeration recooling mode, all fans of the cooling tower 18 and the cooling water pump 17 are at the highest frequency. The lower the cooling tower inlet wet bulb temperature t WB is, the lower the cooling inlet water temperature t W4 of the natural cooling heat exchanger module 13 is correspondingly, the larger the heat exchange temperature difference and the heat exchange amount between low-temperature cooling water and chilled water in the natural cooling heat exchanger module 13 are, namely, the larger the precooling amount of the low-temperature cooling water to the chilled water is, the lower the chilled inlet water temperature t W2 of the evaporator 4 is, the smaller the deviation from the chilled total outlet water temperature target value t W3S is, so the refrigeration load of the water cooling water machine module 5 and the operation power consumption of the compressor 1 are also smaller, and the refrigerating energy efficiency of a unit is higher.
The unit centralized controller module 15 controls the operation capacity of the compressor 1 according to the deviation value of the freezing total outlet water temperature t W3 from the target value t W3S. Unloading the compressor 1 at t W3＜tW3S -e; when t W3＞tW3S +e, loading the compressor 1; at t W3S-e≤tW3≤tW3S + e, the operating capacity of the compressor 1 remains unchanged.
The unit centralized controller module 15 controls the flow distribution of the third control valve 16 according to the temperature t W6 of the cooled water outlet of the water-cooled condenser 2. The lower the cooling tower inlet wet bulb temperature t WB is, the lower the cooling tower outlet water temperature is, namely the cooling inlet water temperature t W4 of the natural cooling heat exchanger module 13 is the same as the cooling inlet water temperature of the water-cooled condenser 2, and the lower the cooling outlet water temperature t W6 of the water-cooled condenser 2 is; at t W6＜tW6S, the opening of the third control valve 16 from the port a to the port c is gradually decreased, i.e. the opening of the port a to the port b is increased, so as to decrease the flow rate of the cooling water entering the water-cooled condenser 2 until t W6≥tW6S. At this time, as the flow rate of the cooling water entering the natural cooling heat exchanger module 13 increases, the heat exchange amount between the low-temperature cooling water and the chilled water in the natural cooling heat exchanger module 13 increases, that is, the precooling capacity of the low-temperature cooling water to the chilled water increases, thereby reducing the chilled water inlet temperature t W2 of the evaporator 4, finally reducing the refrigeration load of the water cooling water machine module 5 and the operation power consumption of the compressor 1, and improving the refrigeration energy efficiency of the unit.
Third mode, natural cooling mode. At t WB≤tW3S-Δt2, the compressor 1 is stopped, the first control valve 10 is turned off, the second control valve 14 is turned on, and the cooling water pump 17 and the cooling tower 18 are in operation. The low-temperature cooling water cooled by the cooling tower 18 is delivered to the third control valve 16 by the cooling water pump 17, and then all or part of the cooling water enters the natural cooling heat exchanger module 13 through the interface b of the third control valve 16 to cool the chilled water with relatively high temperature.
The chilled water entering the unit is conveyed to the second control valve 14 by the chilled water pump 9 after passing through the chilled water filter 8, then enters the natural cooling heat exchanger module 13 through the chilled water pipe 6, exchanges heat with the low-temperature cooling water flowing from the cooling tower and having relatively low temperature in the natural cooling heat exchanger module 13, and the chilled water temperature after being cooled by the low-temperature cooling water is directly reduced to be within the allowable deviation e of the target value t W3S of the total chilled water temperature, and then continuously flows to the evaporator 4. Since the compressor 1 is stopped, the refrigerant in the evaporator 4 is in a stagnant state, and heat exchange between the refrigerant and chilled water does not occur.
At the same time, the low-temperature cooling water is increased in temperature after absorbing the heat of the chilled water in the natural cooling heat exchanger module 13, then flows to the water inlet of the cooling tower 18 through the cooling water pipe 7, is reduced in temperature after discharging the heat to the outdoor low-temperature air in the cooling tower 18, and is then re-conveyed to the natural cooling heat exchanger module 13 through the third control valve 16 by the cooling water pump, thus repeatedly circulating.
The unit centralized controller module 15 controls the operation number and the operation frequency of the cooling tower fans according to the deviation of the freezing total outlet water temperature t W3 and the target value t W3S thereof, and the freezing total outlet water temperature t W3 is equal to the evaporator inlet water temperature t W2.
A. When t W3＜tW3S -e, the running number and running frequency of fans of the cooling tower 18 are gradually reduced to reduce the cooling capacity of outdoor air in the cooling tower 18 to cooling water, improve the cooling inlet temperature t W4 of the natural cooling heat exchanger module 13, further reduce the heat exchange temperature difference and heat exchange quantity between low-temperature cooling water and chilled water in the natural cooling heat exchanger module 13, and further improve the total chilled outlet water temperature t W3; when only 1 fan is in the lowest frequency operation and still meets the condition t W3＜tW3S -e, the opening from the electric three-way valve interface a to the interface c is gradually increased so as to bypass part of low-temperature cooling water to the water-cooled condenser 2, reduce the flow rate of the low-temperature cooling water entering the natural cooling heat exchanger module 13, reduce the heat exchange amount between the low-temperature cooling water and the chilled water in the natural cooling heat exchanger module 13, namely reduce the cooling capacity of the low-temperature cooling water to the chilled water, thereby improving the total chilled water outlet temperature t W3 and controlling the deviation between the total chilled water outlet temperature t W3 and the target value t W3S within the allowable deviation e.
B. When t W3＞tW3S +e, gradually reducing the opening from the electric three-way valve interface a to the interface c, namely, gradually increasing the opening from the electric three-way valve interface a to the interface b, so as to increase the flow of the low-temperature cooling water entering the natural cooling heat exchanger module 13, and improve the heat exchange amount between the low-temperature cooling water and the chilled water in the natural cooling heat exchanger module 13, namely, improve the cooling capacity of the low-temperature cooling water to the chilled water, thereby reducing the total chilled water outlet temperature t W3, and controlling the deviation between the total chilled water outlet temperature t W3 and the target value t W3S within the allowable deviation e. When the opening degrees of the electric three-way valve interfaces a to c are completely closed, namely after all low-temperature cooling water conveyed by the cooling water pump 17 flows to the natural cooling heat exchanger module 13, if the condition of t W3＞tW3S +e is still met, the running number and the running frequency of fans of the cooling tower 18 are gradually increased, so that the cooling capacity of outdoor low-temperature air in the cooling tower 18 to the cooling water is improved, the cooling water inlet temperature t W4 of the natural cooling heat exchanger module 13 is reduced, and the heat exchange temperature difference and the heat exchange quantity between the low-temperature cooling water and the freezing water in the natural cooling heat exchanger module 13 are further improved, so that the total freezing water outlet temperature t W3 is reduced; the deviation from the target value t W3S is controlled to be within the allowable deviation e.
C. When t W3S-e≤tW3≤tW3S +e, the running number and running frequency of fans of the cooling tower 18 are kept unchanged, and meanwhile, the opening degrees from the interface a of the third control valve 16 to the interface b and the interface c are kept unchanged.
While embodiments of the present application have been illustrated and described above, it will be appreciated that the above described embodiments are illustrative and should not be construed as limiting the application. The present application is subject to various changes and modifications without departing from the spirit and scope thereof, and such changes and modifications fall within the scope of the application as hereinafter claimed.

Claims (7)

1. A control method of a water-cooling integrated water chilling unit with a natural cooling function comprises a water-cooling water chilling unit module (5), a freezing hydraulic power module (12), a natural cooling heat exchanger module (13), a cooling heat rejection module (19) and a centralized controller module (15) for sending control instructions to the modules; the method is characterized in that: the water-cooling chiller module (5) comprises a compressor (1), a water-cooling condenser (2), a throttling device (3) and an evaporator (4) which are sequentially connected and form a circulation loop; the freezing hydraulic power module (12) comprises a freezing water filter (8), a freezing water pump (9), a first control valve (10) and a second control valve (14), wherein an outlet of the freezing water pump (9) is respectively connected with a freezing water inlet of the first control valve (10) and a freezing water inlet of the second control valve (14) through a freezing water pipe (6), a freezing water outlet of the first control valve (10) is respectively connected with a freezing water inlet of the evaporator (4) and a freezing water outlet of the natural cooling heat exchanger module (13) through the freezing water pipe (6), and a freezing water outlet of the second control valve (14) is connected with a freezing water inlet of the natural cooling heat exchanger module (13) through the freezing water pipe (6); the cooling heat rejection module (19) comprises a third control valve (16), a cooling water pump (17) and a cooling tower (18), wherein an inlet of the cooling water pump (17) is connected with a cooling water outlet at the bottom of the cooling tower (18) through a cooling water pipe (7), the third control valve (16) controls cooling water at an outlet of the cooling water pump (17) to flow to the water-cooled condenser (2) and/or the natural cooling heat exchanger module (13), and a cooling water outlet of the water-cooled condenser (2) and a cooling water outlet of the natural cooling heat exchanger module (13) are connected to a top water inlet of the cooling tower (18) through the cooling water pipe (7); the freezing water outlet of the freezing water pump (9), the freezing water inlet and the freezing water outlet of the evaporator (4), the cooling water inlet and the cooling water outlet of the natural cooling heat exchanger module (13), the cooling water outlet of the water cooling condenser (2) and the air inlet side of the cooling tower (18) are all provided with sensors; the centralized controller module (15) controls each fan, the first control valve (10), the second control valve (14), the third control valve (16) and the throttling device (3) of the compressor (1), the chilled water pump (9), the cooling water pump (17) and the cooling tower (18) according to data acquired by the sensors;
The centralized controller module (15) controls the operation mode of the unit according to the difference between the inlet wet bulb temperature t WB of the cooling tower and the target value t W3S of the total frozen outlet water temperature, and the unit comprises a mechanical refrigeration mode, a natural cooling precooling and mechanical refrigeration recooling mode and a natural cooling mode;
When the unit is in a mechanical refrigeration mode, and when t WB≥tW3S-Δt1 is reached, deltat 1 is-3-9 ℃, the compressor (1) is operated, the first control valve (10) is electrified, the second control valve (14) is powered off, and the cooling water pump (17) and the cooling tower (18) are in an operation state; chilled water entering the unit passes through a chilled water filter (8) and is sequentially conveyed to a first control valve (10) and an evaporator (4) by a chilled water pump (9), and heat exchange is carried out between the chilled water and low-temperature low-pressure refrigerant which is relatively low in temperature and flows from a throttling device (3) in the evaporator (4);
The low-temperature low-pressure gas refrigerant coming out of the evaporator (4) enters the compressor (1), is compressed into high-temperature high-pressure gas, then enters the water-cooled condenser (2), discharges a large amount of heat released in the condensation process to the cooling water to heat the cooling water, and is condensed into high-pressure liquid; then, the high-pressure liquid refrigerant enters a throttling device (3), throttled and depressurized into low-temperature low-pressure refrigerant, then enters an evaporator (4), absorbs relatively high-temperature chilled water heat to cool the low-pressure refrigerant, evaporates into low-pressure gas, then returns to a compressor (1) again to be compressed into high-temperature high-pressure gas, and repeatedly circulates in this way;
The cooling water absorbs condensation heat discharged by the high-temperature high-pressure refrigerant in the water-cooling condenser (2) and then rises in temperature, then is led to the cooling tower (18) from a cooling water outlet of the water-cooling condenser (2) through the cooling water pipe (7), discharges heat to outdoor air in the cooling tower (18) and then reduces in cooling water temperature, and then is conveyed to the third control valve (16) by the cooling water pump (17) and then enters the water-cooling condenser (2), and the circulation is repeated;
The unit centralized controller module (15) controls the running number and the frequency of fans of the cooling tower (18) according to the cooling water outlet temperature t W6 of the water-cooled condenser (2), and when t W6＜tW6S is carried out, t W6S is the lowest cooling water outlet temperature, the range is 20-30 ℃, and the running number and the running frequency of the fans of the cooling tower (18) are gradually reduced; if only 1 fan still meets the condition t W6＜tW6S when running at the lowest frequency, controlling the flow distribution proportion of cooling water through a third control valve (16), gradually reducing the flow rate of the cooling water entering the water-cooled condenser (2), namely gradually increasing the flow rate of the cooling water entering the natural cooling heat exchanger module (13) until t W6≥tW6S;
When the unit is in a natural cooling precooling and mechanical refrigeration sub-cooling mode, and when t W3S-Δt2＜tWB＜tW3S-Δt1 is carried out, deltat 1 is-3-9 ℃, deltat 2 is 4-16 ℃, the compressor (1) is operated, the first control valve (10) is powered off, the second control valve (14) is powered on, and the cooling water pump (17) and the cooling tower (18) are in an operating state; the low-temperature cooling water cooled by the cooling tower (18) is conveyed to a third control valve (16) by a cooling water pump (17), and then is split into two paths, wherein one path enters a water-cooling condenser (2) to absorb the condensation heat of high-temperature high-pressure gas refrigerant, and the other path enters a natural cooling heat exchanger module (13) to precool chilled water with relatively high temperature;
The chilled water entering the unit is conveyed to a second control valve (14) by a chilled water pump (9) after passing through a chilled water filter (8), then enters a natural cooling heat exchanger module (13) by a chilled water pipe (6), exchanges heat with low-temperature cooling water flowing from a cooling tower and having relatively low temperature in the natural cooling heat exchanger module (13), releases heat to the low-temperature cooling water, the temperature of the chilled water is reduced after the low-temperature cooling water is precooled by the low-temperature cooling water, the chilled water continuously flows to an evaporator (4) by the chilled water pipe (6), and the low-temperature cooling water continuously flows to a water inlet of a cooling tower (18) by a cooling water pipe (7) after the heat temperature of the chilled water absorbed by the low-temperature cooling water in the natural cooling heat exchanger module (13) is increased;
The low-temperature low-pressure gas refrigerant coming out of the evaporator (4) enters the compressor (1), is compressed into high-temperature high-pressure gas, then enters the water-cooled condenser (2), discharges a large amount of heat released in the condensation process to low-temperature cooling water to heat the low-temperature cooling water, and is condensed into high-pressure liquid; then, the high-pressure liquid refrigerant enters a throttling device (3), is throttled and depressurized into low-temperature low-pressure refrigerant, then enters an evaporator (4), absorbs heat of chilled water precooled by low-temperature cooling water, cools the chilled water again, evaporates into low-pressure gas, and then returns to a compressor (1) again to be compressed into high-temperature high-pressure gas, and thus the circulation is repeated;
The temperature of the chilled water cooled again by the low-temperature low-pressure refrigerant is reduced to be within the allowable deviation e of the target value t W3S, e is 0.3-3 ℃, and then the chilled water leaves the unit from the chilled water outlet of the evaporator (4);
Cooling water heated by high-temperature high-pressure refrigerant in the water-cooled condenser (2) and cooling water heated by chilled water in the natural cooling heat exchanger module (13) are collected through the cooling water pipe (7) and then led to a water inlet of the cooling tower (18), heat is discharged to outdoor air in the cooling tower (18) and then the cooling water temperature is reduced, and then the cooling water is respectively conveyed to the water-cooled condenser (2) and the natural cooling heat exchanger module (13) through the third control valve (16) by the cooling water pump (17);
When the unit operates in a natural cooling precooling and mechanical refrigeration sub-cooling mode, all fans and cooling water pumps (17) of a cooling tower (18) are at the highest frequency, the lower the inlet wet bulb temperature t WB of the cooling tower is, the lower the cooling inlet water temperature t W4 of the natural cooling heat exchanger module (13) is correspondingly, the larger the heat exchange temperature difference and heat exchange amount between low-temperature cooling water and chilled water in the natural cooling heat exchanger module (13) is, namely the larger the precooling amount of the low-temperature cooling water to the chilled water is, the lower the chilled inlet water temperature t W2 of an evaporator (4) is, the smaller the deviation from the total chilled outlet water temperature target value t W3S is, so that the refrigerating load of the water cooling water machine module (5) and the running power consumption of a compressor (1) are also lower, and the refrigerating energy efficiency of the unit is higher;
The unit centralized controller module (15) controls the running capacity of the compressor (1) according to the deviation value of the total frozen water outlet temperature t W3 and the target value t W3S, and when t W3＜tW3S -e, the compressor (1) is unloaded; when t W3＞tW3S +e, loading the compressor (1); when t W3S-e≤tW3≤tW3S +e, the operating capacity of the compressor (1) remains unchanged;
The unit centralized controller module (15) controls the flow distribution proportion of cooling water through a third control valve (16) according to the cooling water outlet temperature t W6 of the water-cooled condenser (2), and the lower the cooling tower inlet wet bulb temperature t WB is, the lower the cooling tower (18) outlet water temperature is, namely the lower the natural cooling heat exchanger module (13) cooling water inlet temperature t W4 is, the lower the water-cooled condenser (2) cooling water outlet temperature t W6 is; when t W6＜tW6S, gradually reducing the flow of cooling water entering the water-cooled condenser (2), namely gradually increasing the flow of cooling water entering the natural cooling heat exchanger module (13), until t W6≥tW6S; at the moment, along with the increase of the flow of cooling water entering the natural cooling heat exchanger module (13), the heat exchange amount between low-temperature cooling water and chilled water in the natural cooling heat exchanger module (13) is increased, namely the precooling capacity of the low-temperature cooling water to the chilled water is improved, so that the chilled water inlet temperature t W2 of the evaporator (4) is reduced, the refrigeration load of the water cooling water machine module (5) and the operation power consumption of the compressor (1) are finally reduced, and the refrigeration energy efficiency of a unit is improved;
When the unit is in a natural cooling mode, when t WB≤tW3S-Δt2, deltat 2 is 4-16 ℃, the compressor (1) stops running, the first control valve (10) is powered off, the second control valve (14) is powered on, the cooling water pump (17) and the cooling tower (18) are in an operating state, low-temperature cooling water cooled by the cooling tower (18) is conveyed to the third control valve (16) by the cooling water pump (17), and then all or part of the cooling water enters the natural cooling heat exchanger module (13) through the third control valve (16) to cool and cool relatively high-temperature chilled water;
The chilled water entering the unit is conveyed to a second control valve (14) by a chilled water pump (9) after passing through a chilled water filter (8), then enters a natural cooling heat exchanger module (13) by a chilled water pipe (6), exchanges heat with low-temperature cooling water flowing from a cooling tower and having relatively low temperature in the natural cooling heat exchanger module (13), and the temperature of the chilled water cooled by the low-temperature cooling water is directly reduced to be within the allowable deviation e of a total chilled water outlet temperature target value t W3S, wherein e is 0.3-3 ℃;
Simultaneously, the temperature of the low-temperature cooling water is increased after the low-temperature cooling water absorbs the heat of the chilled water in the natural cooling heat exchanger module (13), then the low-temperature cooling water flows to the water inlet of the cooling tower (18) through the cooling water pipe (7), the temperature of the cooling water is reduced after the heat is discharged to the outdoor low-temperature air in the cooling tower (18), and then the cooling water is conveyed to the natural cooling heat exchanger module (13) again through the third control valve (16) by the cooling water pump (17), and the cooling water is repeatedly circulated in the same way;
The unit centralized controller module (15) controls the running number and running frequency of the cooling tower fans according to the deviation of the total frozen water outlet temperature t W3 and the target value t W3S thereof, and the total frozen water outlet temperature t W3 is equal to the frozen water inlet temperature t W2 of the evaporator (4);
When t W3＜tW3S -e is carried out, the operation number and the operation frequency of each fan of the cooling tower (18) are gradually reduced, so that the cooling capacity of outdoor air in the cooling tower (18) to cooling water is reduced, the cooling inlet temperature t W4 of the natural cooling heat exchanger module (13) is improved, the heat exchange temperature difference and the heat exchange quantity between low-temperature cooling water and chilled water in the natural cooling heat exchanger module (13) are further reduced, and the total chilled outlet water temperature t W3 is improved; when only 1 fan is in the lowest frequency operation and still meets the condition t W3＜tW3S -e, part of low-temperature cooling water is bypassed to flow to the water-cooled condenser (2) so as to reduce the flow rate of the low-temperature cooling water entering the natural cooling heat exchanger module (13), reduce the heat exchange amount between the low-temperature cooling water and the chilled water in the natural cooling heat exchanger module (13), namely reduce the cooling capacity of the low-temperature cooling water on the chilled water, and further improve the total chilled water temperature t W3, so that the deviation between the total chilled water temperature t W3 and the target value t W3S is controlled within the allowable deviation e;
When t W3＞tW3S +e, gradually increasing the flow of low-temperature cooling water entering the natural cooling heat exchanger module (13), and improving the heat exchange amount between the low-temperature cooling water and the chilled water in the natural cooling heat exchanger module (13), namely improving the cooling capacity of the low-temperature cooling water to the chilled water, so as to reduce the total chilled water outlet temperature t W3, and controlling the deviation between the total chilled water outlet temperature t W3 and the target value t W3S within the allowable deviation e; after all low-temperature cooling water conveyed by the cooling water pump (17) flows to the natural cooling heat exchanger module (13), if the condition of t W3＞tW3S +e is still met, the running number and the running frequency of each fan of the cooling tower (18) are gradually increased so as to improve the cooling capacity of outdoor low-temperature air in the cooling tower (18) to the cooling water, reduce the cooling water inlet temperature t W4 of the natural cooling heat exchanger module (13), and further improve the heat exchange temperature difference and heat exchange quantity between the low-temperature cooling water and the chilled water in the natural cooling heat exchanger module (13), thereby reducing the total chilled water outlet temperature t W3; controlling the deviation of the target value t W3S from the target value t W3S within the allowable deviation e;
When t W3S-e≤tW3≤tW3S +e, the running number and the running frequency of fans of the cooling tower (18) are kept unchanged, and meanwhile, the opening degrees from the interface a of the third control valve (16) to the interfaces b and c are respectively kept unchanged.
2. The control method of the water-cooling integrated chiller with the natural cooling function according to claim 1, wherein the control method comprises the following steps: the compressor (1) is selected from a screw compressor, a scroll compressor, a centrifugal compressor or other type of compressor.
3. The control method of the water-cooling integrated chiller with the natural cooling function according to claim 1, wherein the control method comprises the following steps: the throttling device (3) is selected from a thermal expansion valve, an electronic expansion valve, an electric butterfly valve or other types of throttling elements.
4. The control method of the water-cooling integrated chiller with the natural cooling function according to claim 1, wherein the control method comprises the following steps: the first control valve (10) and the second control valve (14) are selected from a switch type electric two-way valve or a proportion type electric two-way valve so as to realize that chilled water output by the chilled water pump (9) in different operation modes directly enters the evaporator (4) or enters the natural cooling heat exchanger module (13) before entering the evaporator (4); or the freezing hydraulic module (12) further comprises an expansion tank (11).
5. The control method of the water-cooling integrated chiller with the natural cooling function according to claim 1, wherein the control method comprises the following steps: the third control valve (16) adopts an electric three-way valve or two electric two-way valves which are respectively communicated with the water-cooling condenser (2) and the natural cooling heat exchanger module (13) so as to control the flow distribution proportion of the cooling water conveyed by the cooling water pump (17) between the natural cooling heat exchanger module (13) and the water-cooling condenser (2).
6. The control method of the water-cooling integrated chiller with the natural cooling function according to claim 1, wherein the control method comprises the following steps: the cooling tower (18) is selected from an open cooling tower, a closed cooling tower or other types of cooling towers.
7. The control method of the water-cooling integrated chiller with the natural cooling function according to claim 1, wherein the control method comprises the following steps: the delta t 1 is 3 ℃, t W6S is 25 ℃, delta t 2 is 8 ℃, and e is 0.5 ℃.
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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101650056A (en) * 2009-09-09 2010-02-17 北京康孚环境控制有限公司 Combined cold supply system of cooling towers and water cooling unit and control method thereof
CN104776731A (en) * 2015-03-31 2015-07-15 清华大学 System and method for freezing resistance of cooling tower in winter by utilizing indirect evaporative cooling
CN106032919A (en) * 2015-03-13 2016-10-19 阿里巴巴集团控股有限公司 Chilled-water cooling system
CN206055810U (en) * 2016-09-30 2017-03-29 安徽中烟工业有限责任公司 A kind of United system of air-conditioning
CN111565543A (en) * 2020-05-11 2020-08-21 葛洲坝节能科技有限公司 Water-cooling natural cooling refrigerant direct cooling refrigeration system
CN112628899A (en) * 2021-01-06 2021-04-09 山东通想智能科技有限公司 Multi-cold source conversion device for data machine room and control method
CN116007078A (en) * 2021-10-21 2023-04-25 中国移动通信集团设计院有限公司 Method, device and equipment for acquiring operation parameters of refrigeration system
CN220601671U (en) * 2023-08-11 2024-03-15 浙江国祥股份有限公司 Water-cooling integrated water chilling unit with natural cooling function

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101650056A (en) * 2009-09-09 2010-02-17 北京康孚环境控制有限公司 Combined cold supply system of cooling towers and water cooling unit and control method thereof
CN106032919A (en) * 2015-03-13 2016-10-19 阿里巴巴集团控股有限公司 Chilled-water cooling system
CN104776731A (en) * 2015-03-31 2015-07-15 清华大学 System and method for freezing resistance of cooling tower in winter by utilizing indirect evaporative cooling
CN206055810U (en) * 2016-09-30 2017-03-29 安徽中烟工业有限责任公司 A kind of United system of air-conditioning
CN111565543A (en) * 2020-05-11 2020-08-21 葛洲坝节能科技有限公司 Water-cooling natural cooling refrigerant direct cooling refrigeration system
CN112628899A (en) * 2021-01-06 2021-04-09 山东通想智能科技有限公司 Multi-cold source conversion device for data machine room and control method
CN116007078A (en) * 2021-10-21 2023-04-25 中国移动通信集团设计院有限公司 Method, device and equipment for acquiring operation parameters of refrigeration system
CN220601671U (en) * 2023-08-11 2024-03-15 浙江国祥股份有限公司 Water-cooling integrated water chilling unit with natural cooling function

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