CN111089371A - Electronic factory building cold source station control system and control method thereof - Google Patents
Electronic factory building cold source station control system and control method thereof Download PDFInfo
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- CN111089371A CN111089371A CN201911286185.6A CN201911286185A CN111089371A CN 111089371 A CN111089371 A CN 111089371A CN 201911286185 A CN201911286185 A CN 201911286185A CN 111089371 A CN111089371 A CN 111089371A
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- 238000000034 method Methods 0.000 title claims abstract description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 134
- 239000002699 waste material Substances 0.000 abstract description 4
- 238000001816 cooling Methods 0.000 description 9
- 230000009286 beneficial effect Effects 0.000 description 4
- 230000007547 defect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000005057 refrigeration Methods 0.000 description 1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- 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
-
- 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
- F24F11/85—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
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F2140/00—Control inputs relating to system states
- F24F2140/10—Pressure
- F24F2140/12—Heat-exchange fluid pressure
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Physics & Mathematics (AREA)
- Fuzzy Systems (AREA)
- Mathematical Physics (AREA)
- Air Conditioning Control Device (AREA)
Abstract
The invention relates to a cold source station control system of an electronic factory building, which comprises a controller, a water supply main pipe, a water return main pipe, a plurality of water chilling units, a plurality of end users, a primary pump set, a secondary pump set and a balance pipe. A cold source station control method of an electronic factory building comprises the steps of S1, selecting the most unfavorable end user from all the end users; s2, comparing the measured secondary water supply and return pressure difference with a set value by the second pressure sensors at two sides of the most unfavorable end user, and confirming the working frequency of the secondary pump set and the number of secondary pumps by the controller according to the comparison value, thereby adjusting the water supply of the secondary pump set to the user group. The cold supply insufficiency and the cold supply waste of the system are avoided, and the normal operation of the system is facilitated.
Description
Technical Field
The invention relates to a control system and a control method for a cold source station of an electronic factory building.
Background
Electronic plants, namely users, each electronic plant user forms a user group, a plurality of end users exist in the user group, and the user group generally needs refrigeration water cooling all the year round. Therefore, it is very important to perform energy saving control on the premise of ensuring the cooling requirement.
The conventional control method has the defects that the conventional system is designed to be a primary pump with a constant flow rate, the secondary pump is a variable flow rate system, most of the conventional systems are designed to be a primary pump, and the secondary pumps are all variable flow rate systems. When the load of the selected end user changes, the secondary pump follows the change of the secondary pump, frequency conversion and number adjustment are carried out, when the requirement on the secondary pump side is greater than the supply on the primary pump side, secondary side return water which is not cooled is directly returned to a suction inlet of the secondary pump from the balance pipe, when the requirement on the secondary pump side is less than the supply on the primary pump side, chilled water on the primary pump side is directly returned to the suction inlet of the refrigerating unit from the balance pipe, and the two conditions can cause vicious cycle or cooling waste of insufficient cooling of the system and are not beneficial to the normal operation of the system.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the system and the method overcome the defects of the prior art, and solve the problems that the conventional system for controlling the cold source station of the electronic factory building is easy to have vicious circle of insufficient cooling or waste of cooling and is not beneficial to the normal operation of the system.
The technical scheme adopted by the invention for solving the technical problems is as follows:
a cold source station control system of an electronic factory building comprises a controller, a water supply main pipe, a water return main pipe, a plurality of water chilling units, a plurality of end users, a primary pump set, a secondary pump set and a balance pipe;
the water inlet end of the water supply main pipe is connected with the water outlet end of each water chilling unit, the water outlet end of the water supply main pipe is connected with the water inlet end of each end user, and the secondary pump group is arranged on a pipeline of the water supply main pipe and is suitable for secondary water supply to each end user;
the water outlet end of the water return main pipe is respectively connected with the water inlet ends of the water chilling units, the water inlet end of the water return main pipe is connected with the water outlet end of each terminal user, and the water inlet end of each group of water chilling units is provided with a primary pump;
two ends of the balance pipe are respectively connected with the water supply main pipe and the water return main pipe;
the water supply main pipe and the water return main pipe are respectively provided with a first pressure sensor which is suitable for detecting the pressure difference of the water supply main pipe and the water return main pipe at two sides of the primary pump set;
the two ends of the inlet and the outlet of each end user are respectively provided with a second pressure sensor which is suitable for detecting the water supply and return pressure difference of the end user;
the controller is respectively and electrically connected with each first pressure sensor, each second pressure sensor, each primary pump and each secondary pump.
In another aspect, a method for controlling a cold source station of an electronic factory building adopts the system for controlling the cold source station of the electronic factory building; the method comprises the following steps:
s1, selecting the most unfavorable end user from the end users;
s2, comparing the measured secondary water supply and return pressure difference with a set value by the second pressure sensors on two sides of the most unfavorable end user, and confirming the working frequency of a secondary pump group and the number of secondary pumps by the controller according to the comparison value so as to adjust the water supply of the secondary pump group to the user group;
meanwhile, the primary water supply and return pressure difference at two sides of the primary pump set is measured through the two first pressure sensors, the primary water supply and return pressure difference is compared with a set value of the primary pump, the working frequency of the primary pump set is controlled by the controller according to the comparison value, the primary side water supply and return pressure difference is guaranteed to be micro-positive pressure, and the PID adjusting speed of the primary side pump set is higher than the adjusting speed of the secondary pump set.
The invention has the beneficial effects that:
the cold source station control system of the electronic factory building is suitable for detecting the worst end user (the user really lack of water) in a plurality of end users according to the second pressure sensors on the two sides of each end user, and is suitable for knowing the pressure difference of the water supply and return pipe in time according to the two first pressure sensors, so that the controller can conveniently adjust the pressure difference from the water supply and return main pipe to the micro positive pressure in time.
The invention provides a control method of a cold source station of an electronic factory building, which comprises the steps of firstly selecting the most unfavorable end user, comparing the differential pressure of the most unfavorable end user with a set value, and controlling a secondary pump set to start working to supply cold water to a user group by a controller when the differential pressure value of the most unfavorable end user exceeds a preset value so as to ensure sufficient cold supply; meanwhile, the primary pump controls the water supply main pipe and the water return main pipe to be micro-positive pressure according to the pressure difference reflected by the first pressure sensor so as to avoid insufficient cooling.
The most unfavorable tail end is adjusted by the secondary pump, the primary pump adjusts the micro positive pressure difference of the water supply and return header pipe of the primary pump, and the adjusting speed of the primary pump is slightly higher than that of the secondary pump, so that the system supplies water as required while the secondary pump does not snatch water, and energy is saved; the secondary pump is adjusted according to the least favorable end user, and if the least favorable end has reached the demand, then all other users of the system have reached the demand.
Drawings
The invention is further described below with reference to the accompanying drawings.
FIG. 1 is a schematic diagram of a control system for a cold source station of an electronic factory building according to the present invention;
the system comprises a water supply main pipe 1, a water return main pipe 2, a balance pipe 3, a primary pump group 4, a secondary pump group 5, a first pressure sensor 6, a second pressure sensor 7 and a second pressure sensor.
Detailed Description
The invention will now be further described with reference to specific examples. These drawings are simplified schematic diagrams only illustrating the basic structure of the present invention in a schematic manner, and thus show only the constitution related to the present invention.
Example one
As shown in fig. 1, a control system for a cold source station of an electronic factory building is characterized by comprising a controller, a water supply main pipe 1, a water return main pipe 2, a plurality of water chilling units, a plurality of end users, a primary pump group 4, a secondary pump group 5 and a balance pipe 3.
The water inlet end of the water supply main pipe 1 is connected with the water outlet ends of the water chilling units, the water outlet end of the water supply main pipe 1 is connected with the water inlet end of each end user, and the secondary pump unit 5 is arranged on a pipeline of the water supply main pipe 1 and is suitable for supplying water to each end user secondarily;
the water outlet end of the return main pipe 2 is respectively connected with the water inlet ends of the water chilling units, the water inlet end of the return main pipe 2 is connected with the water outlet end of each end user, and the water inlet end of each water chilling unit is provided with a primary pump;
two ends of the balance pipe 3 are respectively connected with the water supply main pipe 1 and the water return main pipe 2; the balance pipe 3 (surplus and loss pipe) is a communicating pipe between the water supply main pipes, wherein water can flow in two directions, and the pressure of the water can be high, so that the balance pipe is used for adjusting the water pressure balance between the water supply main pipe 1 and the water return main pipe 2.
The water supply main pipe 1 and the water return main pipe 2 are respectively provided with a first pressure sensor 6 which is suitable for detecting the pressure difference of the water supply main pipe and the water return main pipe at two sides of the primary pump group 4;
the two ends of the inlet and the outlet of each end user are respectively provided with a second pressure sensor 7 which is suitable for detecting the water supply and return pressure difference of the end user;
the controller is respectively electrically connected with each first pressure sensor 6, each second pressure sensor 7, each primary pump and each secondary pump.
During operation, when the consumption of the end user is changed, the frequency modulation or the number control of the secondary pumps can be caused, so that the supply according to the requirement can be realized along with the change of the consumption of the end. The pressure of a water supply and return main pipe on the primary pump side is changed due to the change of the secondary pump side, the primary pump side needs to be adjusted according to the change of the pressure difference, and the adjusting speed needs to be slightly higher than that of the secondary pump.
If a large amount of water flows from the water supply main pipe 1 to the water return main pipe 2 in the balance pipe 3, the supply on the primary pump side is too large and is larger than the requirement on the secondary pump side, and primary side internal circulation is formed, so that energy is wasted. If a large amount of water flows from the return water header pipe 2 to the water supply header pipe 1 in the balance pipe 3, the supply of the primary pump side is smaller than the requirement of the secondary pump side, so that the water is robbed by the secondary pump side, the effect is increasingly poor, and the vicious cycle of the system is caused.
Now, the control system of the present invention is adapted to detect the most unfavorable user (the user who is really lack of water) according to the second pressure sensors 7 on both sides of each user, and is adapted to adjust the pressure difference between the water supply and return main pipe to the slight positive pressure difference in time according to the pressure difference between the two first pressure sensors 6.
Example two
Based on the electronic factory building cold source station control system, a method for controlling the electronic factory building cold source station is provided, and the method comprises the following steps:
s1, selecting the most unfavorable end user from the end users;
it is the least readily available water that there will always be one end user in a group of users; what we need to do is to select the worst end user first, then use the worst end user as the starting standard of the secondary pump set 5, and adjust the secondary pump set 5 according to the worst end, because the worst end has already reached the demand, then all other user ends of the system have reached the demand.
By collecting the pressure difference across each end user on site (site ensures that each end user has water supply because of the many manual valves on the pipeline), and by observing their data, the end user with the smallest pressure difference among the end users is considered to be the most adverse end user under the same design condition.
S2, comparing the measured secondary water supply and return pressure difference with a set value by the second pressure sensors 7 at two sides of the most unfavorable end user, and confirming the working frequency of the secondary pump set 5 and the number of secondary pumps by the controller according to the comparison value, thereby adjusting the water supply of the secondary pump set 5 to the user group;
meanwhile, the primary water supply and return pressure difference at two sides of the primary pump group 4 is measured through the two second pressure sensors 7, the primary water supply and return pressure difference is compared with a set value of the primary pump, the working frequency of the primary pump group 4 is controlled by the controller according to the comparison value, the primary water supply and return pressure difference is guaranteed to be micro-positive pressure, and the PID adjusting speed of the primary side pump group is higher than the adjusting speed of the secondary pump group 5.
The control method of the invention avoids insufficient cooling and waste of cooling of the system, and is beneficial to the normal operation of the system.
In light of the foregoing description of the preferred embodiment of the present invention, many modifications and variations will be apparent to those skilled in the art without departing from the spirit and scope of the invention. The technical scope of the present invention is not limited to the content of the specification, and must be determined according to the scope of the claims.
Claims (2)
1. A cold source station control system of an electronic factory building is characterized by comprising a controller, a water supply main pipe, a water return main pipe, a plurality of water chilling units, a plurality of end users, a primary pump set, a secondary pump set and a balance pipe;
the water inlet end of the water supply main pipe is connected with the water outlet end of each water chilling unit, the water outlet end of the water supply main pipe is connected with the water inlet end of each end user, and the secondary pump group is arranged on a pipeline of the water supply main pipe and is suitable for secondary water supply to each end user;
the water outlet end of the water return main pipe is respectively connected with the water inlet ends of the water chilling units, the water inlet end of the water return main pipe is connected with the water outlet end of each terminal user, and the water inlet end of each group of water chilling units is provided with a primary pump;
two ends of the balance pipe are respectively connected with the water supply main pipe and the water return main pipe;
the water supply main pipe and the water return main pipe are respectively provided with a first pressure sensor which is suitable for detecting the pressure difference of the water supply main pipe and the water return main pipe at two sides of the primary pump set;
the two ends of the inlet and the outlet of each end user are respectively provided with a second pressure sensor which is suitable for detecting the water supply and return pressure difference of the end user;
the controller is respectively and electrically connected with each first pressure sensor, each second pressure sensor, each primary pump and each secondary pump.
2. A method for controlling a cold source station of an electronic factory building is characterized in that the system for controlling the cold source station of the electronic factory building as claimed in claim 1 is adopted; the method comprises the following steps:
s1, selecting the most unfavorable end user from the end users;
s2, comparing the measured secondary water supply and return pressure difference with a set value by the second pressure sensors on two sides of the most unfavorable end user, and confirming the working frequency of a secondary pump group and the number of secondary pumps by the controller according to the comparison value so as to adjust the water supply of the secondary pump group to the user group;
meanwhile, the primary water supply and return pressure difference at two sides of the primary pump set is measured through the two first pressure sensors, the primary water supply and return pressure difference is compared with a set value of the primary pump, the working frequency of the primary pump set is controlled by the controller according to the comparison value, the primary side water supply and return pressure difference is guaranteed to be micro-positive pressure, and the PID adjusting speed of the primary side pump set is higher than the adjusting speed of the secondary pump set.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911286185.6A CN111089371A (en) | 2019-12-13 | 2019-12-13 | Electronic factory building cold source station control system and control method thereof |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911286185.6A CN111089371A (en) | 2019-12-13 | 2019-12-13 | Electronic factory building cold source station control system and control method thereof |
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| CN111089371A true CN111089371A (en) | 2020-05-01 |
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| CN201911286185.6A Withdrawn CN111089371A (en) | 2019-12-13 | 2019-12-13 | Electronic factory building cold source station control system and control method thereof |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113983675A (en) * | 2021-11-10 | 2022-01-28 | 上海观燃智能科技有限公司 | Bypass differential pressure variable frequency regulation air conditioner chilled water system and hydraulic balance method thereof |
| CN114427741A (en) * | 2022-01-25 | 2022-05-03 | 清华大学 | Air conditioner cold water system control method and device, electronic equipment and storage medium |
| CN114576812A (en) * | 2021-12-01 | 2022-06-03 | 华信咨询设计研究院有限公司 | Variable flow control method and system for water supply temperature time-varying cold water system |
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| CN206369306U (en) * | 2017-01-09 | 2017-08-01 | 深圳市海源节能科技有限公司 | Once and secondary pump variable volume energy-saving control system |
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| CN211177250U (en) * | 2019-12-13 | 2020-08-04 | 南京卓恒科技有限公司 | Cold source station control system of electronic factory building |
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Patent Citations (6)
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| KR20090010893A (en) * | 2007-07-24 | 2009-01-30 | 야마타케 코포레이션 | Water supply control system and water supply control method |
| CN105042801A (en) * | 2015-09-01 | 2015-11-11 | 湖南集森节能环保科技有限公司 | Energy-saving control method and system for chilled water pump group |
| CN206369306U (en) * | 2017-01-09 | 2017-08-01 | 深圳市海源节能科技有限公司 | Once and secondary pump variable volume energy-saving control system |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113983675A (en) * | 2021-11-10 | 2022-01-28 | 上海观燃智能科技有限公司 | Bypass differential pressure variable frequency regulation air conditioner chilled water system and hydraulic balance method thereof |
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| CN114576812A (en) * | 2021-12-01 | 2022-06-03 | 华信咨询设计研究院有限公司 | Variable flow control method and system for water supply temperature time-varying cold water system |
| CN114576812B (en) * | 2021-12-01 | 2023-12-26 | 华信咨询设计研究院有限公司 | Variable flow control method and system for water supply temperature time-varying cold water system |
| CN114427741A (en) * | 2022-01-25 | 2022-05-03 | 清华大学 | Air conditioner cold water system control method and device, electronic equipment and storage medium |
| CN114427741B (en) * | 2022-01-25 | 2022-12-02 | 清华大学 | Air conditioner cold water system control method and device, electronic equipment and storage medium |
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Application publication date: 20200501 |