CN114440410A - Method for carrying out variable flow control on freezing and cooling water pumps based on heat exchange efficiency - Google Patents
Method for carrying out variable flow control on freezing and cooling water pumps based on heat exchange efficiency Download PDFInfo
- Publication number
- CN114440410A CN114440410A CN202210131635.XA CN202210131635A CN114440410A CN 114440410 A CN114440410 A CN 114440410A CN 202210131635 A CN202210131635 A CN 202210131635A CN 114440410 A CN114440410 A CN 114440410A
- Authority
- CN
- China
- Prior art keywords
- water
- cooling
- cooling water
- temperature
- water pump
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000000498 cooling water Substances 0.000 title claims abstract description 69
- 238000000034 method Methods 0.000 title claims abstract description 20
- 238000007710 freezing Methods 0.000 title claims abstract description 17
- 230000008014 freezing Effects 0.000 title claims abstract description 17
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 156
- 238000001816 cooling Methods 0.000 claims abstract description 43
- 238000005265 energy consumption Methods 0.000 claims abstract description 21
- 238000012544 monitoring process Methods 0.000 claims description 15
- 238000004378 air conditioning Methods 0.000 claims description 14
- 230000003247 decreasing effect Effects 0.000 claims description 9
- 238000006243 chemical reaction Methods 0.000 claims description 7
- 230000007613 environmental effect Effects 0.000 abstract description 3
- 239000007788 liquid Substances 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 2
- 230000005494 condensation Effects 0.000 description 2
- 238000009833 condensation Methods 0.000 description 2
- 238000004134 energy conservation Methods 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000005057 refrigeration Methods 0.000 description 1
Images
Classifications
-
- 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
- F24F11/50—Control or safety arrangements characterised by user interfaces or communication
- F24F11/54—Control or safety arrangements characterised by user interfaces or communication using one central controller connected to several sub-controllers
-
- 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
- F24F11/50—Control or safety arrangements characterised by user interfaces or communication
- F24F11/52—Indication arrangements, e.g. displays
-
- 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
- F24F11/50—Control or safety arrangements characterised by user interfaces or communication
- F24F11/61—Control or safety arrangements characterised by user interfaces or communication using timers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/62—Control or safety arrangements characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
- F24F11/63—Electronic processing
- F24F11/64—Electronic processing using pre-stored data
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/70—Control systems characterised by their outputs; Constructional details thereof
- F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
- F24F11/83—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers
- F24F11/84—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers using valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/70—Control systems characterised by their outputs; Constructional details thereof
- F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
- F24F11/83—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers
- F24F11/85—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers using variable-flow pumps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F11/00—Control or safety arrangements
- F24F11/70—Control systems characterised by their outputs; Constructional details thereof
- F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
- F24F11/87—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling absorption or discharge of heat in outdoor units
- F24F11/871—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling absorption or discharge of heat in outdoor units by controlling outdoor fans
-
- 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
- F24F2110/10—Temperature
- F24F2110/12—Temperature of the outside air
-
- 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
- F24F2110/20—Humidity
- F24F2110/22—Humidity of the outside air
-
- 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
- F24F2140/10—Pressure
- F24F2140/12—Heat-exchange fluid pressure
-
- 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
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Human Computer Interaction (AREA)
- Signal Processing (AREA)
- Physics & Mathematics (AREA)
- Fuzzy Systems (AREA)
- Mathematical Physics (AREA)
- Thermal Sciences (AREA)
- Air Conditioning Control Device (AREA)
- Other Air-Conditioning Systems (AREA)
Abstract
The invention discloses a method for carrying out variable flow control on a freezing water pump and a cooling water pump based on heat exchange efficiency, which processes data by applying a PID algorithm through performance parameter data of a freezing water system and the cooling water system running under different working conditions and establishes a relevant parameter and energy consumption model; calculating energy consumption values of different operation parameters selected under different environments and system loads through the models; finding out system operation parameters which enable the energy consumption of the cooling water system to be lowest under the specified environment and system load conditions and when the system requirements are met; and finally, controlling the cooling water system through the operation parameters to ensure that the energy consumption is the lowest. The invention comprehensively considers the influence of environmental factors and system cold load on the energy consumption of the cooling water system, coordinates and controls the fan frequency of the cooling tower and the operating frequency of the cooling pump, and ensures that the comprehensive energy consumption of the cooling water system is the lowest on the premise of ensuring the high-efficiency operation of the water chilling unit.
Description
Technical Field
The invention belongs to the technical field of energy and energy conservation, and particularly relates to a method for carrying out variable flow control on a freezing water pump and a cooling water pump based on heat exchange efficiency.
Background
In modern intelligent buildings, a central air conditioning system is an indispensable component, but the central air conditioning system is also an energy-consuming household of the modern buildings and is in an increasing trend. Under such a large environment, how to make the central air-conditioning system more energy-saving and more efficient, how to reasonably improve the comprehensive energy efficiency ratio of the central air-conditioning system, and how to attach more and more importance to the current users.
The cooling water/chilled water system is an important component of the central air-conditioning system, the energy consumption of the cooling water/chilled water system accounts for about 15% -20% of that of the central air-conditioning system, and the energy-saving control of the cooling water/chilled water system has very important significance on overall energy conservation. With the development of the water chilling unit technology, the flow of the cooling water system can be changed within the range of 30% -130%, when the air conditioning load and the outdoor environment are changed, the adjustment of the operation parameters of the cooling pump and the cooling tower becomes the main energy-saving control mode of the cooling water system, and the most common control methods in the current engineering include constant-temperature-difference variable-flow control, constant-cooling-water return-water temperature control, constant-flow control and the like. However, the above control method does not take into consideration the influence of the comprehensive energy efficiency, system load and environmental factors of the cooling water/chilled water system on the energy consumption of the cooling water/chilled water system.
Disclosure of Invention
The invention aims to realize the lowest energy consumption control of a chilled water system and a cooling water system under different outdoor dry bulb temperature, humidity and system cold load conditions and on the premise of ensuring that the temperature of a condenser is the required temperature of the system.
The technical scheme adopted by the invention is as follows:
the embodiment of the invention provides a method for carrying out variable flow control on a freezing water pump and a cooling water pump based on heat exchange efficiency, which is applied to the control of a central air-conditioning system, wherein the operation of the central air-conditioning system relates to cooling water circulation, chilled water circulation and air circulation of a fresh air system, the cooling water circulation brings heat in a refrigerating unit into a cooling tower through cooling water for cooling, the chilled water circulation brings cold energy generated in the refrigerating unit into an air treatment unit through chilled water, the chilled water circulation carries out heat exchange with the air circulation through the air treatment unit, a variable-speed cooling water pump is arranged on the cooling water circulation, and the variable-speed freezing water pump is arranged on the chilled water circulation; the method is characterized by comprising the following steps:
s1, adjusting the temperature difference between the supplied water and the returned water of the chilled water according to the heat exchange performance of a refrigerating unit to obtain a preset temperature difference value of the supplied water and the returned water;
s2, controlling the chilled water pump according to the temperature difference value of the supplied water and the returned water, wherein the control of the start-stop frequency and the adjustment of the chilled water flow are included;
s3, controlling the cooling water pump according to the temperature difference value of the supplied water and the returned water, and synchronously referring to the influence of the temperature and the humidity of the outdoor environment;
s4, judging whether the cooling return water temperature is close to the current wet bulb temperature and the deviation value, performing frequency conversion control on a cooling tower fan, controlling the rotating speed of the cooling tower fan, and increasing or decreasing the online number of the cooling tower in operation;
wherein the step S1 further includes:
s1.1, judging the heat exchange performance of a refrigerating unit, wherein the preset water supply and return temperature difference value is gradually reduced in preset unit time, the reduced temperature in the unit time is 0.1 ℃, the running efficiency (COP) of the system is calculated in real time through the total energy consumption and the refrigerating capacity of the refrigerating unit, a water pump part and an air handling unit, and then the point with the highest running efficiency (COP) of the system is compared, and the preset water supply and return temperature difference value is obtained and is the highest point of the heat exchange capacity of the heat exchanger;
wherein the step S2 further includes:
s2.1, calculating the temperature difference value of the supplied and returned water obtained by the step A to obtain the control frequency of the chilled water pump through a PID algorithm, increasing or decreasing the number of the chilled water pumps which stop running according to the control frequency, and synchronously carrying out comprehensive control by referring to the pressure difference value of the supplied and returned water of the chilled water, the cold and heat demand detected by a cold and heat meter in real time and the chilled water supply temperature, wherein the pressure difference value is equal to or higher than the set value of the water pressure difference;
wherein the step S3 further includes:
s3.1, switching to control the start and stop of the cooling water pump manually or automatically according to the requirement, and remotely accessing to a centralized monitoring system;
s3.2, calculating to obtain the control frequency of the cooling water pumps by using a PID algorithm according to the temperature difference value of the supplied and returned water, increasing or decreasing the number of the cooling water pumps which are stopped, and keeping the pump lifts of the cooling water pumps consistent when a plurality of cooling water pumps of the same type are operated simultaneously;
wherein the step S4 further includes:
s4.1, performing variable frequency control, and reducing the rotating speed of a fan of the cooling tower when the value obtained by subtracting the current wet bulb temperature from the cooling return water temperature is less than 2 ℃; when the temperature of cooling return water minus the temperature of the current wet bulb is more than 2 ℃, increasing the rotating speed of a fan of the cooling tower;
and S4.2, controlling the rotating speed of the cooling tower fan through manual or automatic switching according to the requirement, and remotely accessing the centralized monitoring system.
Furthermore, the running number of the freezing water pumps and the cooling water pumps is larger than that of the refrigerating unit.
Further, the unit time is based on 5 minutes.
Furthermore, the temperature difference range value of the temperature difference value of the water supply and return is 4-8 ℃.
The invention has the advantages that the influence of environmental factors and system cold load on the energy consumption of the cooling water system and the chilled water system is comprehensively considered, the fan frequency of the cooling tower and the operation frequency of the refrigerating pump and the cooling pump are coordinately controlled, and the comprehensive energy consumption of the chilled water and the cooling water system is lowest on the premise of ensuring the high-efficiency operation of the water chilling unit.
The invention is further described with reference to the following figures and examples.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without limiting the invention.
Fig. 1 is a flow chart of chilled water circulation control according to the present invention.
Fig. 2 is a flow chart of cooling water circulation control according to the present invention.
Detailed Description
The present invention is further described in the following description with reference to specific embodiments and the accompanying drawings, wherein the details are set forth in order to provide a thorough understanding of the present invention, but it is apparent that the present invention can be embodied in many other forms different from the description herein, and one skilled in the art can make similar generalizations and deductions based on the practical application without departing from the spirit of the present invention, and therefore, the scope of the present invention should not be limited by the contents of this specific embodiment.
The method comprises the steps of processing data by applying a PID algorithm through performance parameter data of a chilled water system and a cooling water system running under different working conditions, and establishing a relevant parameter and energy consumption model; calculating energy consumption values of different operation parameters selected under different environments and system loads through the models; finding out system operation parameters which enable the energy consumption of the cooling water system to be lowest under the specified environment and system load conditions and when the system requirements are met; and finally, controlling the cooling water system through the operation parameters to ensure that the energy consumption is the lowest.
Referring to fig. 1 and 2, the method for performing variable flow control on a freezing water pump and a cooling water pump based on heat exchange efficiency of the invention is applied to control of a central air-conditioning system, wherein the operation of the central air-conditioning system relates to cooling water circulation, chilled water circulation and air circulation of a fresh air system, the cooling water circulation brings heat in a refrigerating unit into a cooling tower through cooling water for cooling, the chilled water circulation brings cold energy generated in the refrigerating unit into an air treatment unit through chilled water, the chilled water circulation performs heat exchange with the air circulation through the air treatment unit, a variable speed cooling water pump is arranged on the cooling water circulation, and the variable speed freezing water pump is arranged on the chilled water circulation; the method is characterized by comprising the following steps:
s1, adjusting the temperature difference between the supplied water and the returned water of the chilled water according to the heat exchange performance of a refrigerating unit to obtain a preset temperature difference value of the supplied water and the returned water;
s2, controlling the chilled water pump according to the temperature difference value of the supplied water and the returned water, wherein the control of the start-stop frequency and the adjustment of the chilled water flow are included;
s3, controlling the cooling water pump according to the temperature difference value of the supplied water and the returned water, and synchronously referring to the influence of the temperature and the humidity of the outdoor environment;
s4, judging whether the cooling return water temperature is close to the current wet bulb temperature and the deviation value, performing frequency conversion control on a cooling tower fan, controlling the rotating speed of the cooling tower fan, and increasing or decreasing the online number of the cooling tower in operation;
wherein the step S1 further includes:
s1.1, judging the heat exchange performance of a refrigerating unit, wherein the preset water supply and return temperature difference value is gradually reduced in preset unit time, the reduced temperature in the unit time is 0.1 ℃, the running efficiency (COP) of the system is calculated in real time through the total energy consumption and the refrigerating capacity of the refrigerating unit, a water pump part and an air handling unit, and then the point with the highest running efficiency (COP) of the system is compared, and the preset water supply and return temperature difference value is obtained and is the highest point of the heat exchange capacity of the heat exchanger;
wherein the step S2 further includes:
s2.1, calculating the temperature difference value of the supplied and returned water obtained by the step A to obtain the control frequency of the chilled water pump through a PID algorithm, increasing or decreasing the number of the chilled water pumps which stop running according to the control frequency, and synchronously carrying out comprehensive control by referring to the pressure difference value of the supplied and returned water of the chilled water, the cold and heat demand detected by a cold and heat meter in real time and the chilled water supply temperature, wherein the pressure difference value is equal to or higher than the set value of the water pressure difference;
wherein the step S3 further includes:
s3.1, switching to control the start and stop of the cooling water pump manually or automatically according to the requirement, and remotely accessing to a centralized monitoring system;
s3.2, calculating to obtain the control frequency of the cooling water pumps by using a PID algorithm according to the temperature difference value of the supplied and returned water, increasing or decreasing the number of the cooling water pumps which are stopped, and keeping the pump lifts of the cooling water pumps consistent when a plurality of cooling water pumps of the same type are operated simultaneously;
wherein the step S4 further includes:
s4.1, performing variable frequency control, and reducing the rotating speed of a fan of the cooling tower when the value obtained by subtracting the current wet bulb temperature from the cooling return water temperature is less than 2 ℃; when the temperature of cooling return water minus the temperature of the current wet bulb is more than 2 ℃, increasing the rotating speed of a fan of the cooling tower;
and S4.2, controlling the rotating speed of the cooling tower fan through manual or automatic switching according to the requirement, and remotely accessing the centralized monitoring system.
Furthermore, the running number of the freezing water pumps and the cooling water pumps is larger than that of the refrigerating unit.
Further, the unit time is based on 5 minutes.
Furthermore, the temperature difference range value of the temperature difference value of the water supply and return is 4-8 ℃.
Further, by applying the method of the present invention, the cooling water circulation, the chilled water circulation and the air circulation of the fresh air system relate to a refrigerating unit, a cooling tower, an air handling unit, a variable speed cooling water pump and a variable speed chilled water pump, and the applied components comprise:
(1) communication interface (heat pump set): transmitting data to a gateway by using interfaces such as Modbus and the like, and finally monitoring equipment parameters on an upper computer interface;
(2) a water flow switch: the general heat pump unit is provided with itself, and the cold and hot water flow main machine does not operate;
(3) a liquid level switch: the water replenishing devices are used, and the high liquid level and the low liquid level are respectively one;
(4) a water pipe pressure sensor: measuring the cold and hot water supply and return pipes;
(5) water pipe temperature sensor: measuring the cold and hot water supply and return pipes;
(6) outdoor temperature and humidity sensor: measuring outdoor temperature and humidity, and calculating dew point temperature and wet bulb temperature;
(7) switching on and off the valve: the heat pump unit is installed on the cold water pipeline and the hot water pipeline and is in linkage control with the heat pump unit;
(8) bypass valve: independent differential pressure control is realized, and the system does not need to be displayed;
(9) cold and heat flow meter: measuring the flow on the total cold and hot water pipes, and calculating the cold supply and heat quantity;
(10) heat pump set switch board: the electricity consumption of the unit is measured by a multifunctional remote transmission electric energy meter;
(11) cold and hot water pump frequency conversion cabinet: exchanging signals with a controller, and controlling the output frequency of the frequency converter through temperature difference and pressure difference; having a manual frequency modulation knob; the frequency conversion cabinet is provided with a multifunctional remote transmission electric energy meter.
Further, the monitoring content used by applying the method of the invention comprises:
equipment monitoring: on-site/remote start-stop control and state display (operation, fault and manual operation and automation) of a heat pump unit, a cold water pump and a hot water pump; other parameters such as the load rate, the temperature of inlet and outlet water, the condensation approaching temperature and the like of the heat pump unit;
the system functions are as follows: the method comprises the following steps of performing a timing power-on and power-off function, a one-key power-on and power-off function, accumulated running time display, and preferential starting of high-efficiency equipment or equipment with the lowest running time;
monitoring energy consumption: monitoring energy consumption, voltage, current, power factor and the like of a host, a water pump and the like;
energy monitoring: monitoring the total cooling capacity, the total heating capacity and other parameters of the cold and heat meter;
temperature and humidity monitoring: the total inlet and outlet water temperature of cold supply and heat supply, outdoor temperature and humidity, dew point temperature and wet bulb temperature; temperature compensation is set on an upper computer; when the acquisition value of the sensor is not in the conventional range, the sensor fault is processed;
the temperature of the cold supply and heat supply main water inlet and outlet is redundant: comparing the main water inlet and outlet temperature values of cold supply and heat supply with the average temperature value of the main machine in operation, when the difference is more than 2 ℃ (the difference can be set), performing sensor fault alarm, and using the average temperature of the main machine in operation to replace the temperature of the main pipe of the sensor to control the system (the upper computer is provided with a sensor temperature/main machine temperature manual switching button);
pressure monitoring: the total inlet and outlet water pressure of cold supply and heat supply; when the acquisition value of the sensor is not in the conventional range, the sensor fault is processed;
water replenishing liquid level: high and low level displays (typically not monitored);
switching on and off the valve: local/remote, switch control and in-place signal display (failure is displayed if the switch is not in place for more than 1 minute after being started); when the valve is closed, the red light flickers, and the red light is normally on when the valve is closed; when the valve is opened, the green light flickers, and the green light is normally on when the valve is opened;
adjusting a valve: a mechanical manual adjusting device and an opening signal feedback display are required;
frequency conversion control of cold and hot water pumps: automatically carrying out frequency conversion and feeding back a frequency value according to the temperature difference and the pressure difference; the function of manually setting frequency by an upper computer is provided; when a plurality of pumps of the same type operate, the frequency should be consistent, so that the pump lifts are kept consistent;
redundancy: the air conditioning units are mutually standby; the cold and hot water pumps are mutually standby;
start-stop sequence: when the system program is started or stopped and the interlocking unit is started, the electric butterfly valves at the cold water pipe and the hot water pipe are opened, and the cold water pump and the hot water pump are sequentially started. After the water flow is confirmed by the water flow switch, the air-cooled heat pump unit is started. When the air-cooled heat pump unit is stopped, the water pump is stopped and the valve is closed after a certain time delay. When any set of refrigeration system stops running, all the units, the water pumps and the electric butterfly valves corresponding to the system are closed in an interlocking way;
linkage of a host: performing host joint control according to the load efficiency curve to enable the host joint control to operate in a high-energy efficiency interval; when a plurality of hosts are started, when the load rate or the flow of each running host is obviously different, an alarm is given to remind a manager to check the problems of the hosts, and the host linkage control is not suitable to be started at the moment; the water outlet temperature of the main machine can be manually set on the upper machine;
forming a real-time curve, a historical curve and a report: the heat quantity value, the cold quantity value, the ratio of the heat quantity value to the cold quantity value, the load rate of a heat pump unit, the temperature of cold inlet and outlet water of the heat pump, the condensation approach temperature, the energy consumption of a host and a water pump, the total cold supply quantity, the total heat supply quantity, the total temperature of cold supply and heat supply inlet and outlet water, the outdoor temperature and humidity, the dew point temperature, the wet bulb temperature, the total pressure of cold supply and heat supply inlet and outlet water and the COP curve.
In the invention, when the system is started, the cooling water system is operated for a period of time in a full-power mode (namely, the cooling tower fan, the cooling pump and the freezing pump are operated according to design parameters), and the system enters an optimal control mode after the system is stably started.
The parts not involved in the present invention are the same as or can be implemented using the prior art.
While embodiments of the invention have been disclosed above, it is not limited to the applications listed in the description and the embodiments, which are fully applicable in a variety of fields of endeavor to which the invention pertains, and further modifications may readily be made by those skilled in the art, it being understood that the invention is not limited to the details shown and described herein without departing from the general concepts defined by the claims and the equivalents thereof.
Claims (4)
1. A method for carrying out variable flow control on freezing and cooling water pumps based on heat exchange efficiency is applied to control of a central air-conditioning system, wherein the operation of the central air-conditioning system relates to cooling water circulation, chilled water circulation and air circulation of a fresh air system, the cooling water circulation brings heat in a refrigerating unit into a cooling tower through cooling water for cooling, the chilled water circulation brings cold energy generated in the refrigerating unit into an air treatment unit through chilled water, the chilled water circulation carries out heat exchange with the air circulation through the air treatment unit, a variable-speed cooling water pump is arranged on the cooling water circulation, and a variable-speed freezing water pump is arranged on the chilled water circulation; the method is characterized by comprising the following steps:
s1, adjusting the temperature difference between the supplied water and the returned water of chilled water according to the heat exchange performance of a refrigerating unit to obtain a preset supplied water and returned water temperature difference value;
s2, controlling the chilled water pump according to the temperature difference value of the supplied water and the returned water, wherein the control of the start-stop frequency and the adjustment of the chilled water flow are included;
s3, controlling the cooling water pump according to the temperature difference value of the supplied water and the returned water, and synchronously referring to the influence of the temperature and the humidity of the outdoor environment;
s4, judging whether the cooling return water temperature is close to the current wet bulb temperature and the deviation value, performing frequency conversion control on a cooling tower fan, controlling the rotating speed of the cooling tower fan, and increasing or decreasing the online number of the cooling tower in operation;
wherein the step S1 further includes:
s1.1, judging the heat exchange performance of a refrigerating unit, wherein the preset water supply and return temperature difference value is gradually reduced in preset unit time, the reduced temperature in the unit time is 0.1 ℃, the running efficiency (COP) of the system is calculated in real time through the total energy consumption and the refrigerating capacity of the refrigerating unit, a water pump part and an air handling unit, and then the point with the highest running efficiency (COP) of the system is compared, and the preset water supply and return temperature difference value is obtained and is the highest point of the heat exchange capacity of the heat exchanger;
wherein the step S2 further includes:
s2.1, calculating the temperature difference value of the supplied and returned water obtained by the step A to obtain the control frequency of the chilled water pump through a PID algorithm, increasing or decreasing the number of the chilled water pumps which stop running according to the control frequency, and synchronously carrying out comprehensive control by referring to the pressure difference value of the supplied and returned water of the chilled water, the cold and heat demand detected by a cold and heat meter in real time and the chilled water supply temperature, wherein the pressure difference value is equal to or higher than the set value of the water pressure difference;
wherein the step S3 further includes:
s3.1, switching to control the start and stop of the cooling water pump manually or automatically according to the requirement, and remotely accessing to a centralized monitoring system;
s3.2, calculating to obtain the control frequency of the cooling water pumps by using a PID algorithm according to the temperature difference value of the supplied and returned water, increasing or decreasing the number of the cooling water pumps which are stopped, and keeping the pump lifts of the cooling water pumps consistent when a plurality of cooling water pumps of the same type are operated simultaneously;
wherein the step S4 further includes:
s4.1, performing variable frequency control, and reducing the rotating speed of a fan of the cooling tower when the value obtained by subtracting the current wet bulb temperature from the cooling return water temperature is less than 2 ℃; when the temperature of cooling return water minus the temperature of the current wet bulb is more than 2 ℃, increasing the rotating speed of a fan of the cooling tower;
and S4.2, controlling the rotating speed of the cooling tower fan through manual or automatic switching according to the requirement, and remotely accessing the centralized monitoring system.
2. The method for controlling the variable flow of the freezing water pump and the cooling water pump based on the heat exchange efficiency as claimed in claim 1, wherein the operation number of the freezing water pump and the cooling water pump is larger than that of the refrigerating unit.
3. The method for controlling the variable flow rate of a refrigerating and cooling water pump according to claim 1, wherein the unit time is based on 5 minutes.
4. The method for controlling the variable flow of the freezing and cooling water pump based on the heat exchange efficiency as claimed in claim 1, wherein the temperature difference range of the temperature difference value of the supplied and returned water is 4-8 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210131635.XA CN114440410B (en) | 2022-02-14 | 2022-02-14 | Variable flow control method for freezing and cooling water pump based on heat exchange efficiency |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210131635.XA CN114440410B (en) | 2022-02-14 | 2022-02-14 | Variable flow control method for freezing and cooling water pump based on heat exchange efficiency |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114440410A true CN114440410A (en) | 2022-05-06 |
| CN114440410B CN114440410B (en) | 2023-09-08 |
Family
ID=81372464
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210131635.XA Active CN114440410B (en) | 2022-02-14 | 2022-02-14 | Variable flow control method for freezing and cooling water pump based on heat exchange efficiency |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114440410B (en) |
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114909791A (en) * | 2022-06-17 | 2022-08-16 | 杭州医学院 | Management and control system of central air-conditioning cooling water system of medical building |
| CN114992922A (en) * | 2022-05-20 | 2022-09-02 | 深圳市兴达扬机电安装有限公司 | Cold water control system capable of effectively reducing running time of cold water host |
| CN115164375A (en) * | 2022-07-08 | 2022-10-11 | 南京优助智能科技有限公司 | Flow estimation method and system for central air conditioner cold and heat source system |
| CN115183408A (en) * | 2022-06-17 | 2022-10-14 | 珠海格力电器股份有限公司 | Control method and control device for variable flow operation of cooling water system |
| CN115235051A (en) * | 2022-07-27 | 2022-10-25 | 广州市铭汉科技股份有限公司 | Double-control type efficient cooling water control system |
| CN115307482A (en) * | 2022-06-23 | 2022-11-08 | 新奥数能科技有限公司 | Method and device for determining cleaning strategy of heat exchanger |
| CN115540374A (en) * | 2022-09-30 | 2022-12-30 | 青岛海信日立空调系统有限公司 | Refrigerating unit |
| CN115860445A (en) * | 2022-11-15 | 2023-03-28 | 中核陕西铀浓缩有限公司 | Multi-level cooperative scheduling method for uranium enrichment refrigerating unit and closed cooling tower |
| CN116379655A (en) * | 2023-04-19 | 2023-07-04 | 广州施杰节能科技有限公司 | Cold machine optimizing control system and method |
| CN116582034A (en) * | 2023-05-19 | 2023-08-11 | 淮阴工学院 | Low-energy-consumption permanent magnet outer rotor roller motor control system |
| CN116906965A (en) * | 2023-07-14 | 2023-10-20 | 山东华科规划建筑设计有限公司 | Ground source heat pump energy station and regulation and control method thereof |
| CN117053618A (en) * | 2023-10-12 | 2023-11-14 | 江苏橙智云信息技术有限公司 | Variable-frequency water chilling unit control system and method |
| CN118551672A (en) * | 2024-07-30 | 2024-08-27 | 威鹏晟(山东)机械有限公司 | Performance evaluation and optimization system and method for vacuum pump cooling system |
| CN119146801A (en) * | 2024-11-12 | 2024-12-17 | 深圳市前海能源科技发展有限公司 | Control method, device, equipment and storage medium of transmission and distribution system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201059715Y (en) * | 2007-07-06 | 2008-05-14 | 北京时代嘉华环境控制科技有限公司 | A quality control system for central air-conditioning refrigeration station |
| US20130151019A1 (en) * | 2011-12-12 | 2013-06-13 | Vigilent Corporation | Controlling air temperatures of hvac units |
| CN106369772A (en) * | 2016-11-07 | 2017-02-01 | 深圳市奥宇节能技术股份有限公司 | Safety protection method for variable-flow operation of central air conditioner cooling water system |
| WO2020119038A1 (en) * | 2018-12-14 | 2020-06-18 | 广东美的暖通设备有限公司 | Method and device for controlling air conditioner and air conditioner |
| CN113536525A (en) * | 2021-04-16 | 2021-10-22 | 广州地铁设计研究院股份有限公司 | Global optimal energy-saving control method for central air conditioner |
-
2022
- 2022-02-14 CN CN202210131635.XA patent/CN114440410B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201059715Y (en) * | 2007-07-06 | 2008-05-14 | 北京时代嘉华环境控制科技有限公司 | A quality control system for central air-conditioning refrigeration station |
| US20130151019A1 (en) * | 2011-12-12 | 2013-06-13 | Vigilent Corporation | Controlling air temperatures of hvac units |
| CN106369772A (en) * | 2016-11-07 | 2017-02-01 | 深圳市奥宇节能技术股份有限公司 | Safety protection method for variable-flow operation of central air conditioner cooling water system |
| WO2020119038A1 (en) * | 2018-12-14 | 2020-06-18 | 广东美的暖通设备有限公司 | Method and device for controlling air conditioner and air conditioner |
| CN113536525A (en) * | 2021-04-16 | 2021-10-22 | 广州地铁设计研究院股份有限公司 | Global optimal energy-saving control method for central air conditioner |
Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114992922A (en) * | 2022-05-20 | 2022-09-02 | 深圳市兴达扬机电安装有限公司 | Cold water control system capable of effectively reducing running time of cold water host |
| CN115183408A (en) * | 2022-06-17 | 2022-10-14 | 珠海格力电器股份有限公司 | Control method and control device for variable flow operation of cooling water system |
| CN114909791A (en) * | 2022-06-17 | 2022-08-16 | 杭州医学院 | Management and control system of central air-conditioning cooling water system of medical building |
| CN115307482A (en) * | 2022-06-23 | 2022-11-08 | 新奥数能科技有限公司 | Method and device for determining cleaning strategy of heat exchanger |
| CN115164375B (en) * | 2022-07-08 | 2024-04-26 | 南京优助智能科技有限公司 | Flow estimation method and system for central air conditioner cold and heat source system |
| CN115164375A (en) * | 2022-07-08 | 2022-10-11 | 南京优助智能科技有限公司 | Flow estimation method and system for central air conditioner cold and heat source system |
| CN115235051A (en) * | 2022-07-27 | 2022-10-25 | 广州市铭汉科技股份有限公司 | Double-control type efficient cooling water control system |
| CN115235051B (en) * | 2022-07-27 | 2023-03-14 | 广州市铭汉科技股份有限公司 | Double-control cooling water control system |
| CN115540374A (en) * | 2022-09-30 | 2022-12-30 | 青岛海信日立空调系统有限公司 | Refrigerating unit |
| CN115860445A (en) * | 2022-11-15 | 2023-03-28 | 中核陕西铀浓缩有限公司 | Multi-level cooperative scheduling method for uranium enrichment refrigerating unit and closed cooling tower |
| CN115860445B (en) * | 2022-11-15 | 2024-02-09 | 中核陕西铀浓缩有限公司 | Multi-level collaborative scheduling method for uranium enrichment refrigerating unit and closed cooling tower |
| CN116379655B (en) * | 2023-04-19 | 2023-09-05 | 广州施杰节能科技有限公司 | Cold machine optimizing control system and method |
| CN116379655A (en) * | 2023-04-19 | 2023-07-04 | 广州施杰节能科技有限公司 | Cold machine optimizing control system and method |
| CN116582034A (en) * | 2023-05-19 | 2023-08-11 | 淮阴工学院 | Low-energy-consumption permanent magnet outer rotor roller motor control system |
| CN116906965A (en) * | 2023-07-14 | 2023-10-20 | 山东华科规划建筑设计有限公司 | Ground source heat pump energy station and regulation and control method thereof |
| CN117053618A (en) * | 2023-10-12 | 2023-11-14 | 江苏橙智云信息技术有限公司 | Variable-frequency water chilling unit control system and method |
| CN117053618B (en) * | 2023-10-12 | 2023-12-26 | 江苏橙智云信息技术有限公司 | Variable-frequency water chilling unit control system and method |
| CN118551672A (en) * | 2024-07-30 | 2024-08-27 | 威鹏晟(山东)机械有限公司 | Performance evaluation and optimization system and method for vacuum pump cooling system |
| CN119146801A (en) * | 2024-11-12 | 2024-12-17 | 深圳市前海能源科技发展有限公司 | Control method, device, equipment and storage medium of transmission and distribution system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114440410B (en) | 2023-09-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN114440410B (en) | Variable flow control method for freezing and cooling water pump based on heat exchange efficiency | |
| CN110895016A (en) | Fuzzy self-adaptive based energy-saving group control method for central air-conditioning system | |
| CN109917646B (en) | System and method for optimizing operation of regional cooling and heating equipment | |
| CN108534394B (en) | Group control optimization control method for loading and unloading of double units of ground source heat pump | |
| CN105180538B (en) | Frequency-changeable compressor power distribution unit and its operation method | |
| CN118794108A (en) | Central air conditioning cooling station control system | |
| CN102338448B (en) | High-efficiency energy-saving control system for central air conditioner of large-sized supermarket | |
| CN113790542B (en) | Multi-module water chilling unit and scheduling control method thereof | |
| CN113218040A (en) | Energy efficiency improvement control method for central air-conditioning system | |
| CN114459133A (en) | Energy-saving control method and energy-saving control system for central air-conditioning system | |
| CN106152414B (en) | Air conditioner with surplus indoor unit control method and device | |
| WO2022083283A1 (en) | Ice storage cooling/room-heating/heating air conditioning system controlled by weather forecast, time, temperature, and liquid level | |
| CN203869259U (en) | Variable pressure difference control device based on openness of chilled water valve of tail-end air conditioning equipment | |
| CN212132815U (en) | Intelligent cold station control system | |
| CN107036231A (en) | Cooling tower intelligent energy-saving control method in central air-conditioning monitoring system | |
| CN110425691A (en) | A kind of self-adaptive energy-saving control system of water cooled central air conditioner system | |
| CN203964267U (en) | Central air-conditioning Auto-matching load energy conserving system | |
| CN117804045A (en) | Energy-saving chilled water type air conditioner host control system and method | |
| CN217584809U (en) | A management and control system for the central air-conditioning cooling water system of a medical building | |
| CN200968715Y (en) | Intelligent heat reclamation heat pump cold and hot water set | |
| CN103673230A (en) | Data center complex water-cooling system operation control device and method | |
| CN2608877Y (en) | Automatic control system for central heating | |
| CN108592331B (en) | Cooling tower cold supply mode control method and system of air conditioning system | |
| CN111594989A (en) | Efficient and energy-saving central air-conditioning energy management system and working method thereof | |
| CN206247552U (en) | Central air-conditioning automatic optimal energy-saving controller |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |