CN118049768A - Liquid cooling system control method and device and liquid cooling system - Google Patents
Liquid cooling system control method and device and liquid cooling system Download PDFInfo
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- CN118049768A CN118049768A CN202410452174.5A CN202410452174A CN118049768A CN 118049768 A CN118049768 A CN 118049768A CN 202410452174 A CN202410452174 A CN 202410452174A CN 118049768 A CN118049768 A CN 118049768A
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- 238000001816 cooling Methods 0.000 title claims abstract description 363
- 239000007788 liquid Substances 0.000 title claims abstract description 221
- 238000000034 method Methods 0.000 title claims abstract description 40
- 238000005057 refrigeration Methods 0.000 claims abstract description 245
- 238000007906 compression Methods 0.000 claims abstract description 88
- 230000006835 compression Effects 0.000 claims abstract description 88
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 65
- 239000000110 cooling liquid Substances 0.000 claims description 35
- 238000012937 correction Methods 0.000 claims description 4
- 239000000758 substrate Substances 0.000 claims 1
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 43
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 18
- 238000005516 engineering process Methods 0.000 description 6
- 238000010438 heat treatment Methods 0.000 description 6
- 238000003825 pressing Methods 0.000 description 4
- 239000003507 refrigerant Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000004134 energy conservation Methods 0.000 description 3
- 230000017525 heat dissipation Effects 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 230000007547 defect Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 125000003827 glycol group Chemical group 0.000 description 2
- 230000007774 longterm Effects 0.000 description 2
- 230000000630 rising effect Effects 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000011555 saturated liquid Substances 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 238000010977 unit operation Methods 0.000 description 1
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Abstract
The invention discloses a liquid cooling system control method, a device and a liquid cooling system, wherein the method comprises the following steps: calculating the maximum refrigerating capacity of the liquid cooling system in different refrigerating modes; wherein, the refrigeration mode at least includes: a normal cooling refrigeration mode, a compression refrigeration mode, a normal cooling and compression cascade refrigeration mode; obtaining target required refrigeration capacity of the liquid cooling system; and determining a refrigeration mode of the liquid cooling system according to the maximum refrigeration capacity and the target required refrigeration capacity, and controlling the operation of the liquid cooling system according to the refrigeration mode. The invention solves the problems that the refrigeration mode of the liquid cooling system can only be selected to be started and the judgment of the refrigeration mode is not accurate enough in the prior art, increases the output range of the refrigeration capacity of the liquid cooling system, meets different refrigeration demands, and improves the reliability of the unit.
Description
Technical Field
The invention relates to the technical field of liquid cooling, in particular to a liquid cooling system control method and device and a liquid cooling system.
Background
The liquid cooling technology is an efficient heat dissipation technology, and is widely applied to various high-heat-density fields. As traditional air cooling technology presents a bottleneck in facing high heat density scenarios, the heat dissipation efficiency has far from keeping pace with market demands. Under the background, the liquid cooling technology brings wide attention to various industries by virtue of the technical advantages of ultrahigh energy efficiency, ultrahigh heat density, low-temperature heat transfer, low noise and the like which are incomparable with the traditional air cooling technology, and the liquid cooling technology also becomes a necessary way for solving the heat dissipation pressure and energy conservation challenges.
The existing liquid cooling source is used for refrigerating and cooling the target environment through two modes of compressor refrigeration and normal cooling. When the unit is started, only one mode of the refrigeration and the normal cooling of the compressor can be selected for starting, the two modes can not be started simultaneously, and the starting mode is judged only according to the ambient temperature, so that the mode selection judgment is not accurate and reasonable. After the mode is selected, all loads corresponding to the mode are uniformly controlled to start and stop, the target requirement is not accurately judged, the unit is operated at full load, and the unit is frequently started and stopped near a temperature point, so that long-term reliable operation and energy-saving operation of the unit are not facilitated.
Aiming at the problems that the refrigeration mode of the liquid cooling system can only be selectively started and the judgment of the refrigeration mode is not accurate enough in the related art, no effective solution is proposed at present.
Disclosure of Invention
The invention provides a liquid cooling system control method, a liquid cooling system control device and a liquid cooling system, which at least solve the problems that in the prior art, the refrigeration mode of the liquid cooling system can only be selected to be started, and the judgment of the refrigeration mode is not accurate enough.
In order to solve the above technical problem, according to an aspect of the embodiments of the present invention, there is provided a liquid cooling system control method, including: calculating the maximum refrigerating capacity of the liquid cooling system in different refrigerating modes; wherein, the refrigeration mode at least includes: a normal cooling refrigeration mode, a compression refrigeration mode, a normal cooling and compression cascade refrigeration mode; obtaining target required refrigeration capacity of the liquid cooling system; and determining a refrigeration mode of the liquid cooling system according to the maximum refrigeration capacity and the target required refrigeration capacity, and controlling the operation of the liquid cooling system according to the refrigeration mode.
Further, the calculating the maximum refrigerating capacity of the liquid cooling system in different refrigerating modes comprises: acquiring operation parameters of the liquid cooling system; wherein the operating parameters include at least: the operation parameters of the surface cooler of the liquid cooling system and the operation parameters of the compressor of the liquid cooling system; and calculating the maximum refrigerating capacity of the liquid cooling system in the normal cooling mode according to the operation parameters of the surface cooler, and calculating the maximum refrigerating capacity of the liquid cooling system in the compression cooling mode according to the operation parameters of the compressor.
Further, calculating the maximum refrigerating capacity of the liquid cooling system in the normal cooling refrigerating mode according to the operation parameters of the surface cooler includes: the method comprises the steps of obtaining the number a of the surface coolers, the water inlet and outlet temperature difference t 1 of the surface coolers and the heat capacity x of cooling liquid, and calculating the maximum refrigerating capacity Q1 of the liquid cooling system in the normal cooling refrigerating mode through the following formula: q1=k 1*(a*x*t1), where k 1 is a refrigeration coefficient in the normal cooling refrigeration mode; calculating the maximum refrigerating capacity of the liquid cooling system in the compression refrigerating mode according to the operation parameters of the compressor, wherein the maximum refrigerating capacity comprises the following components: the number n of the compressors, the refrigerating capacity b of the single compressor and the outdoor environment temperature t 2 are obtained, and the maximum refrigerating capacity Q2 of the liquid cooling system in the compression refrigerating mode is calculated through the following formula: q2=k 2*n*(b* k3*t2), where k 2 is a cooling coefficient in the compression cooling mode, and k 3 is an outdoor environment temperature correction coefficient.
Further, obtaining the target required refrigeration capacity of the liquid cooling system includes: acquiring the actual water inlet temperature and the target water outlet temperature of a cooling liquid main pipe of the liquid cooling system; calculating the target required refrigerating capacity according to the actual water inlet temperature and the target water outlet temperature; wherein, the target required refrigeration capacity q=c×m×t 0, c is the specific heat capacity of the cooling liquid, m is the mass of the cooling liquid, and t 0 is the difference between the actual inlet water temperature and the target outlet water temperature.
Further, determining a cooling mode of the liquid cooling system according to the maximum cooling capacity and the target required cooling capacity includes: judging whether the maximum refrigerating capacity in the normal cooling refrigerating mode can meet the target required refrigerating capacity or not; if yes, determining the refrigeration mode of the liquid cooling system as the normal cooling refrigeration mode; otherwise, acquiring the outdoor environment temperature and the water inlet and outlet temperature difference of the liquid cooling system, and determining the refrigeration mode of the liquid cooling system according to the outdoor environment temperature and the water inlet and outlet temperature difference of the liquid cooling system.
Further, determining a cooling mode of the liquid cooling system according to the outdoor environment temperature and the inlet and outlet water temperature difference of the liquid cooling system, including: judging whether the outdoor environment temperature is smaller than a first preset temperature or not; if so, determining the refrigeration mode of the liquid cooling system as the normal cooling and compression cascade refrigeration mode; otherwise, further judging whether the outdoor environment temperature is smaller than a second preset temperature, wherein the second preset temperature is larger than the first preset temperature; when the outdoor environment temperature is not less than the second preset temperature, determining that the refrigeration mode of the liquid cooling system is the compression refrigeration mode; and when the outdoor environment temperature is smaller than the second preset temperature, further judging the refrigeration mode of the liquid cooling system according to the water inlet and outlet temperature difference of the liquid cooling system.
Further, the method for further judging the cooling mode of the liquid cooling system according to the water inlet and outlet temperature difference of the liquid cooling system comprises the following steps: judging whether the water inlet and outlet temperature difference of the liquid cooling system is larger than a preset temperature difference threshold value or not; if so, determining the refrigeration mode of the liquid cooling system as the normal cooling and compression cascade refrigeration mode; otherwise, determining the refrigeration mode of the liquid cooling system as the compression refrigeration mode.
Further, controlling the operation of the liquid cooling system according to the cooling mode includes: when the refrigeration mode of the liquid cooling system is the normal cooling refrigeration mode or the normal cooling and compression cascade refrigeration mode, calculating the opening quantity of fans, and controlling the operation of the fans according to the opening quantity of the fans; and when the refrigerating mode of the liquid cooling system is the compression refrigerating mode or the normal cooling and compression cascade refrigerating mode, calculating the starting quantity of the compressors, and controlling the operation of the compressors according to the starting quantity of the compressors.
According to another aspect of the embodiment of the present invention, there is provided a liquid cooling system control apparatus including: the calculating module is used for calculating the maximum refrigerating capacity of the liquid cooling system in different refrigerating modes; wherein, the refrigeration mode at least includes: a normal cooling refrigeration mode, a compression refrigeration mode, a normal cooling and compression cascade refrigeration mode; the acquisition module is used for acquiring the target required refrigeration capacity of the liquid cooling system; and the control module is used for determining the refrigeration mode of the liquid cooling system according to the maximum refrigeration capacity and the target required refrigeration capacity and controlling the operation of the liquid cooling system according to the refrigeration mode.
According to still another aspect of the embodiment of the present invention, there is provided a liquid cooling system including the liquid cooling system control device described above.
According to yet another aspect of embodiments of the present invention, there is provided a storage medium containing computer-executable instructions for performing a liquid cooling system control method as described above when executed by a computer processor.
In the invention, a liquid cooling system control scheme is provided, the refrigeration system is provided with a normal cooling refrigeration mode, a compression refrigeration mode, a normal cooling mode and a compression cascade refrigeration mode, and the refrigeration capacity parameter is adopted to accurately judge the refrigeration mode of the liquid cooling system, so that the problems that the refrigeration mode of the liquid cooling system can only be switched on and the judgment of the refrigeration mode is not accurate enough are effectively solved, the refrigeration capacity of the normal cooling mode and the compression cascade refrigeration mode is larger than that of a conventional compressor refrigeration mode and a normal cooling mode, the refrigeration capacity output range of the liquid cooling system is enlarged by the three refrigeration modes, different refrigeration demands are met, and the refrigeration operation range of the system is improved.
Drawings
FIG. 1 is a schematic diagram of an alternative configuration of a liquid cooling system according to an embodiment of the present invention;
FIG. 2 is an alternative flow chart of a method of controlling a liquid cooling system according to an embodiment of the present invention;
FIG. 3 is a flow chart of an alternative method of controlling a liquid cooling system according to an embodiment of the present invention;
FIG. 4 is a block diagram of an alternative configuration of a liquid cooling system control device according to an embodiment of the present invention.
Reference numerals illustrate:
1. A compressor; 2. a condenser; 3. a condensing fan; 4. a surface cooler; 5. an evaporator; 6. an electronic expansion valve; 7. a gas-liquid separator; 8. an exhaust temperature sensing bag; 9. a high voltage switch; 10. a low voltage switch; 11. two-way switch valve.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail below with reference to the accompanying drawings, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in this application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise, the "plurality" generally includes at least two.
It should be understood that the term "and/or" as used herein is merely one relationship describing the association of the associated objects, meaning that there may be three relationships, e.g., a and/or B, may represent: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.
It should be understood that although the terms first, second, third, etc. may be used to describe the controllers in the embodiments of the present invention, these controllers should not be limited to these terms. These terms are only used to distinguish between controllers connected to different devices. For example, a first controller may also be referred to as a second controller, and similarly, a second controller may also be referred to as a first controller, without departing from the scope of embodiments of the invention.
The words "if", as used herein, may be interpreted as "at … …" or "at … …" or "in response to a determination" or "in response to a detection", depending on the context. Similarly, the phrase "if determined" or "if detected (stated condition or event)" may be interpreted as "when determined" or "in response to determination" or "when detected (stated condition or event)" or "in response to detection (stated condition or event), depending on the context.
It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a product or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such product or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a commodity or device comprising such elements.
Alternative embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
Example 1
In a preferred embodiment 1 of the present invention, there is provided a liquid cooling system control method which can be directly applied to various liquid cooling systems, and fig. 1 shows an alternative configuration schematic of the liquid cooling system, and as shown in fig. 1, the liquid cooling system includes a plurality of surface coolers and a plurality of compression systems, and the compression systems include a plurality of compressors, condensers, electronic expansion valves, and evaporators. The evaporator uses a plate heat exchanger, the cooling liquid adopts glycol solution, the refrigerant and glycol exchange heat through the plate heat exchanger in the refrigerating mode of the compressor, and the glycol exchange heat through the surface cooler by using a fan and the ring temperature in the normal cooling mode.
For the normal cooling refrigeration mode, the water pump conveys glycol cooling liquid into the surface cooler from the water tank at a certain flow rate and pressure; in the surface cooler, air passes through a filter screen under the action of an axial flow fan and then exchanges heat with glycol cooling liquid in the surface cooler, so that the temperature of the glycol cooling liquid is reduced; after passing through the surface cooler, the glycol cooling liquid is conveyed into the heating equipment, wherein the glycol cooling liquid absorbs the heat of the heating equipment to heat up, and the heating equipment is cooled; the heated glycol cooling liquid returns to the water tank; the glycol cooling liquid with the temperature rising flows back to the water pump and is then conveyed to the surface cooler by the water pump for repeated operation.
For the compression refrigeration mode, during refrigeration operation, refrigerant gas with low temperature and low pressure is sucked by a compressor and is discharged after being compressed into gas with high temperature and high pressure, the gas is cooled into high pressure saturated liquid in an air-cooled condenser, the liquid enters a plate heat exchanger after being throttled and depressurized by a capillary tube (or an expansion valve), the liquid refrigerant evaporates and absorbs heat, so that glycol solution in a water tank is cooled, the liquid refrigerant evaporates and absorbs heat and becomes superheated gas, and the superheated gas is sucked and compressed by the compressor again through a pipeline; the water pump conveys glycol cooling liquid into the surface cooler from the water tank at a certain flow rate and pressure; in the surface cooler, air passes through a filter screen under the action of an axial flow fan and then exchanges heat with glycol cooling liquid in the surface cooler, so that the temperature of the glycol cooling liquid is reduced; after passing through the surface cooler, the glycol cooling liquid is conveyed into the heating equipment, wherein the glycol cooling liquid absorbs the heat of the heating equipment to heat up, and the heating equipment is cooled; the heated glycol cooling liquid returns to the water tank; the glycol cooling liquid with the temperature rising flows back to the water pump and is then conveyed to the surface cooler by the water pump for repeated operation.
Based on the above liquid cooling system, the present invention provides a liquid cooling system control method, specifically, fig. 2 shows an optional flowchart of the method, as shown in fig. 1, and the method includes the following steps S202-S206:
S202: calculating the maximum refrigerating capacity of the liquid cooling system in different refrigerating modes; wherein, the refrigeration mode at least includes: a normal cooling refrigeration mode, a compression refrigeration mode, a normal cooling and compression cascade refrigeration mode;
S204: obtaining target required refrigerating capacity of a liquid cooling system;
s206: and determining a refrigeration mode of the liquid cooling system according to the maximum refrigeration capacity and the target required refrigeration capacity, and controlling the operation of the liquid cooling system according to the refrigeration mode.
In the embodiment, the control scheme of the liquid cooling system is provided, the refrigeration system is provided with a normal cooling refrigeration mode, a compression refrigeration mode, a normal cooling mode and a compression cascade refrigeration mode, the refrigeration capacity parameter is adopted to accurately judge the refrigeration mode of the liquid cooling system, the problems that the refrigeration mode of the liquid cooling system can only be switched on and the judgment of the refrigeration mode is not accurate enough are effectively solved, meanwhile, the refrigeration capacity of the normal cooling mode and the compression cascade refrigeration mode is larger than that of a conventional compressor refrigeration mode and a normal cooling mode, the refrigeration capacity output range of the liquid cooling system is enlarged by the three refrigeration modes, different refrigeration demands are met, and the refrigeration operation range of the system is improved.
In a preferred embodiment of the present invention, calculating the maximum cooling capacity of the liquid cooling system in different cooling modes includes: acquiring operation parameters of a liquid cooling system; wherein the operating parameters include at least: operating parameters of a surface cooler of the liquid cooling system and operating parameters of a compressor of the liquid cooling system; and calculating the maximum refrigerating capacity of the liquid cooling system in the normal cooling refrigerating mode according to the operation parameters of the surface cooler, and calculating the maximum refrigerating capacity of the liquid cooling system in the compression refrigerating mode according to the operation parameters of the compressor.
Specifically, calculating the maximum refrigerating capacity of the liquid cooling system in the normal cooling refrigerating mode according to the operation parameters of the surface cooler comprises the following steps: the method comprises the steps of obtaining the number a of the surface coolers, the water inlet and outlet temperature difference t 1 of the single surface cooler and the heat capacity x of cooling liquid, and calculating the maximum refrigerating capacity Q1 of the liquid cooling system in a normal cooling refrigerating mode through the following formula: q1=k 1*(a*x*t1), where k 1 is a refrigeration coefficient in the normal cooling refrigeration mode; the heat capacity x of the cooling liquid can be calculated by the following formula: taking a cooling liquid as an ethylene glycol solution as an example, c is the specific heat capacity of the ethylene glycol solution with the corresponding concentration of the cooling liquid, and m is the mass of the ethylene glycol solution passing through a single surface cooler, and the heat capacity of the cooling liquid can be obtained through the product.
Calculating the maximum refrigerating capacity of the liquid cooling system in the compression refrigerating mode according to the operation parameters of the compressor, wherein the method comprises the following steps: the method comprises the steps of obtaining the number n of compressors, the refrigerating capacity b of a single compressor and the outdoor environment temperature t 2, and calculating the maximum refrigerating capacity Q2 of the liquid cooling system in a compression refrigerating mode through the following formula: q2=k 2*n*(b* k3*t2), where k 2 is a cooling coefficient in the compression cooling mode, and k 3 is an outdoor environment temperature correction coefficient.
In another preferred embodiment of the present invention, obtaining the target required refrigeration capacity of the liquid cooling system includes: acquiring the actual water inlet temperature and the target water outlet temperature of a cooling liquid main pipe of the liquid cooling system; calculating target required refrigerating capacity according to the actual inlet water temperature and the target outlet water temperature; wherein, the target required refrigeration capacity q=c×m×t 0, c is the specific heat capacity of the cooling liquid, m is the mass of the cooling liquid, and t 0 is the difference between the actual inlet water temperature and the target outlet water temperature.
After determining the maximum refrigerating capacity and the target required refrigerating capacity, determining a refrigerating mode of the liquid cooling system according to the maximum refrigerating capacity and the target required refrigerating capacity, including: judging whether the maximum refrigerating capacity in the normal cooling refrigerating mode can meet the target required refrigerating capacity or not; if so, determining that the refrigeration mode of the liquid cooling system is a normal cooling refrigeration mode; otherwise, acquiring the temperature difference between the outdoor environment temperature and the water inlet and outlet temperature of the liquid cooling system, and determining the refrigeration mode of the liquid cooling system according to the temperature difference between the outdoor environment temperature and the water inlet and outlet temperature of the liquid cooling system.
Specifically, determining a cooling mode of the liquid cooling system according to an outdoor ambient temperature and an inlet and outlet water temperature difference of the liquid cooling system comprises: judging whether the outdoor environment temperature is less than a first preset temperature; if so, determining that the refrigeration mode of the liquid cooling system is a normal cooling and compression cascade refrigeration mode; otherwise, further judging whether the outdoor environment temperature is smaller than a second preset temperature, wherein the second preset temperature is larger than the first preset temperature; when the outdoor environment temperature is not less than the second preset temperature, determining that the refrigeration mode of the liquid cooling system is a compression refrigeration mode; and when the outdoor environment temperature is smaller than the second preset temperature, further judging the refrigeration mode of the liquid cooling system according to the water inlet and outlet temperature difference of the liquid cooling system. Further, the method for further judging the refrigeration mode of the liquid cooling system according to the water inlet and outlet temperature difference of the liquid cooling system comprises the following steps: judging whether the water inlet and outlet temperature difference of the liquid cooling system is larger than a preset temperature difference threshold value or not; if so, determining that the refrigeration mode of the liquid cooling system is a normal cooling and compression cascade refrigeration mode; otherwise, determining the refrigeration mode of the liquid cooling system to be a compression refrigeration mode.
When the refrigerating capacity of the normal cooling mode meets the target requirement, maintaining the normal cooling mode to operate; when the refrigerating capacity of the normal cooling mode does not meet the target requirement, the most reasonable collocation mode of the compression refrigerating mode and the normal cooling mode is automatically selected according to the temperature interval of the outdoor environment and the temperature interval of the inlet water temperature and the outlet water temperature difference. Under the conditions that the outside environment temperature is low and the refrigeration capacity of the normal cooling mode does not meet the target requirement, the method of compensating the normal cooling mode by using the refrigeration mode reduces the energy consumption of the unit and realizes energy conservation.
According to the control mode for automatically selecting the refrigerating mode, intelligent state judgment is performed on the unit operation refrigerating mode, a more reasonable operation mode is selected under complex operation conditions through a method of multiple parameter designs, energy conservation is realized while heat exchange requirements are ensured, the defect that a liquid cooling source is always cold and a compressor is opened in a single mode is overcome, two refrigerating modes can be simultaneously opened, refrigerating capacity is increased, and the refrigerating operation range of the unit is improved.
Further, controlling the operation of the liquid cooling system according to the cooling mode includes: when the refrigeration mode of the liquid cooling system is a normal cooling refrigeration mode or a normal cooling and compression cascade refrigeration mode, the opening number of the fans is calculated, and the operation of the fans is controlled according to the opening number of the fans; when the refrigeration mode of the liquid cooling system is a compression refrigeration mode or a normal cooling and compression cascade refrigeration mode, the starting number of the compressors is calculated, and the operation of the compressors is controlled according to the starting number of the compressors. The refrigeration capacity Q Watch (watch) of a single surface cooler, the actual output refrigeration capacity Q Pressing of a single compressor, the quantity n Wind power of opening fans, the quantity n Pressing of opening compressors, the target refrigeration load Q and the normal cooling maximum refrigeration capacity Q1.n Wind power and n Pressing are integers. Calculating the opening quantity of fans: q < n q Watch (watch) < 110% q; normal cooling and compression cascade refrigeration mode, calculating the starting quantity of compressors: Q-Q1 < n Q Pressing < 110% (Q-Q1); independently starting a compression refrigeration mode, and calculating the starting quantity of compressors: q < n q Pressing < 110% q.
According to the embodiment, the quantity of fans and compressors to be started is calculated according to the actual demand, so that the refrigerating capacity is close to the target demand, frequent start-up and shut-down of the unit are avoided, the defect that all loads are required to be uniformly started or shut down in two modes is overcome, and the reliability of the unit is improved.
In a preferred embodiment 1 of the present invention, another method for controlling a liquid cooling system is provided, specifically, fig. 3 shows an alternative flow chart of the method, and as shown in fig. 3, the method includes the following steps S301 to S314:
s301, starting;
S302, starting up and running a normal cooling refrigeration mode for 10min;
S303, calculating the normal cooling maximum refrigerating capacity Q1=k 1*(a*x*t1), (a=1-8);
S304, calculating a target demand load q=c×m×t 0;
S305, whether the normal cooling refrigerating capacity Q1 is larger than the demand load Q is met, if yes, the step S306 is carried out, and if not, the step S307 is carried out;
S306, maintaining a normal cooling mode, and calculating the number a of fans to be started; calculating the opening quantity of fans: q < a q Watch (watch) < 110% q;
S307, calculating the refrigerating capacity q2=k 2*n*(b* k3*t2), (n=1 to 4);
s308, judging whether the environmental temperature is less than T1, if so, proceeding to step S309, otherwise proceeding to step S310;
S309, keeping the normal cooling refrigeration mode on state, simultaneously starting the compression refrigeration mode, and calculating the required starting number b of compressors; maintaining normal cooling start, simultaneously starting the compressor to supplement cooling capacity, and calculating the starting quantity of the compressors: Q-Q1 < b Q Pressing < 110% (Q-Q1);
s310, whether the environment temperature is less than T2 is met, if yes, the step S312 is carried out, and if not, the step S311 is carried out;
S311, closing a normal cooling refrigeration mode, independently starting a compression refrigeration mode, and calculating the number of required compressors to be started;
S312, whether the water inlet and outlet temperature difference is more than or equal to T3 is met, if yes, the step S313 is carried out, and if not, the step S314 is carried out;
S313, keeping the normal cooling refrigeration mode on state, simultaneously starting the compression refrigeration mode, and calculating the number of required compressors to be started; calculating the starting quantity b of the compressors: Q-Q1 < b Q Pressing < 110% (Q-Q1);
s314, closing the normal cooling mode, independently opening the compression cooling mode, and calculating the required opening quantity c of the compressors: q < c q Pressing < 110% q.
The prior art is to judge whether the refrigeration mode is normal cooling or the compressor is refrigerating according to the ring temperature, the normal cooling and the compressor can not be started simultaneously, the fan and the compressor are switched on and off simultaneously, and the fan and the compressor can only stop running independently when faults occur. According to the invention, the starting quantity of the compressors and the fans can be controlled according to actual demands, and the normal cooling mode and the compressor refrigerating mode can be operated simultaneously, namely the normal cooling mode and the compression cascade refrigerating mode, so that the maximum refrigerating capacity of the unit is improved. The quantity of fans and compressors started according to actual demands enables the refrigerating capacity to be close to target demands, frequent start and stop of the unit are avoided, and reliability of the unit is improved. When T 1 is smaller than the ring temperature and smaller than T 2 and the water inlet and outlet temperature difference is larger, the normal cooling mode is compensated by the compressor cooling mode, the starting quantity of the compressors is reduced, and energy saving is realized.
In the embodiment, the mode judgment of the unit is more accurate through the design of various parameter thresholds, the output refrigerating capacity is adjusted according to the refrigerating capacity demand, the unit is prevented from being frequently started and stopped when running under low load near a temperature point, the energy-saving running of the unit is realized while the refrigerating capacity is ensured, and the long-term reliable running of the unit and the energy saving of the unit are facilitated.
Example 2
Based on the liquid cooling system control method provided in the above embodiment 1, in a preferred embodiment 2 of the present invention, there is further provided a liquid cooling system control device, specifically, fig. 4 shows an optional block diagram of the device, and as shown in fig. 4, the device includes:
A calculating module 402, configured to calculate a maximum cooling capacity of the liquid cooling system in different cooling modes; wherein, the refrigeration mode at least includes: a normal cooling refrigeration mode, a compression refrigeration mode, a normal cooling and compression cascade refrigeration mode;
The acquisition module 404 is connected with the calculation module 402 and is used for acquiring the target required refrigeration capacity of the liquid cooling system;
The control module 406 is connected to the acquisition module 404, and is configured to determine a cooling mode of the liquid cooling system according to the maximum cooling capacity and the target required cooling capacity, and control operation of the liquid cooling system according to the cooling mode.
In the embodiment, the control scheme of the liquid cooling system is provided, the refrigeration system is provided with a normal cooling refrigeration mode, a compression refrigeration mode, a normal cooling mode and a compression cascade refrigeration mode, the refrigeration capacity parameter is adopted to accurately judge the refrigeration mode of the liquid cooling system, the problems that the refrigeration mode of the liquid cooling system can only be switched on and the judgment of the refrigeration mode is not accurate enough are effectively solved, meanwhile, the refrigeration capacity of the normal cooling mode and the compression cascade refrigeration mode is larger than that of a conventional compressor refrigeration mode and a normal cooling mode, the refrigeration capacity output range of the liquid cooling system is enlarged by the three refrigeration modes, different refrigeration demands are met, and the refrigeration operation range of the system is improved.
The calculation module 402 includes: the acquisition submodule is used for acquiring the operation parameters of the liquid cooling system; wherein the operating parameters include at least: operating parameters of a surface cooler of the liquid cooling system and operating parameters of a compressor of the liquid cooling system; and the calculating sub-module is used for calculating the maximum refrigerating capacity of the liquid cooling system in the normal cooling refrigerating mode according to the operation parameters of the surface cooler and calculating the maximum refrigerating capacity of the liquid cooling system in the compression refrigerating mode according to the operation parameters of the compressor.
The calculation submodule comprises: the first calculating unit is used for calculating the maximum refrigerating capacity of the liquid cooling system in the normal cooling refrigerating mode according to the operation parameters of the surface cooler, and comprises the following components: the method comprises the steps of obtaining the number a of the surface coolers, the water inlet and outlet temperature difference t 1 of the single surface cooler and the heat capacity x of cooling liquid, and calculating the maximum refrigerating capacity Q1 of the liquid cooling system in a normal cooling refrigerating mode through the following formula: q1=k 1*(a*x*t1), where k 1 is a refrigeration coefficient in the normal cooling refrigeration mode; the second calculating unit is used for calculating the maximum refrigerating capacity of the liquid cooling system in the compression refrigerating mode according to the operation parameters of the compressor, and comprises the following components: the method comprises the steps of obtaining the number n of compressors, the refrigerating capacity b of a single compressor and the outdoor environment temperature t 2, and calculating the maximum refrigerating capacity Q2 of the liquid cooling system in a compression refrigerating mode through the following formula: q2=k 2*n*(b* k3*t2), where k 2 is a cooling coefficient in the compression cooling mode, and k 3 is an outdoor environment temperature correction coefficient.
The acquisition module 404 includes: the acquisition unit is used for acquiring the actual water inlet temperature and the target water outlet temperature of a cooling liquid main pipe of the liquid cooling system; the third calculation unit is used for calculating the target required refrigerating capacity according to the actual inlet water temperature and the target outlet water temperature; wherein, the target required refrigeration capacity q=c×m×t 0, c is the specific heat capacity of the cooling liquid, m is the mass of the cooling liquid, and t 0 is the difference between the actual inlet water temperature and the target outlet water temperature.
The control module 406 includes: the judging submodule is used for judging whether the maximum refrigerating capacity in the normal cooling refrigerating mode can meet the target required refrigerating capacity or not; the first determining submodule is used for determining that the refrigeration mode of the liquid cooling system is a normal cooling refrigeration mode if the first determining submodule is used for determining that the refrigeration mode of the liquid cooling system is the normal cooling refrigeration mode; and the second determining submodule is used for acquiring the outdoor environment temperature and the water inlet and outlet temperature difference of the liquid cooling system, and determining the refrigeration mode of the liquid cooling system according to the outdoor environment temperature and the water inlet and outlet temperature difference of the liquid cooling system.
The second determination submodule includes: the first judging unit is used for judging whether the outdoor environment temperature is smaller than a first preset temperature or not; the first determining unit is used for determining that the refrigeration mode of the liquid cooling system is a normal cooling and compression cascade refrigeration mode if the liquid cooling system is in the normal cooling and compression cascade refrigeration mode; the second judging unit is used for further judging whether the outdoor environment temperature is smaller than a second preset temperature or not, wherein the second preset temperature is larger than the first preset temperature; the second determining unit is used for determining that the refrigeration mode of the liquid cooling system is a compression refrigeration mode when the outdoor environment temperature is not less than a second preset temperature; and the second determining unit is used for further judging the refrigeration mode of the liquid cooling system according to the water inlet and outlet temperature difference of the liquid cooling system when the outdoor environment temperature is smaller than a second preset temperature.
The second determination unit includes: judging whether the water inlet and outlet temperature difference of the liquid cooling system is larger than a preset temperature difference threshold value or not; if so, determining that the refrigeration mode of the liquid cooling system is a normal cooling and compression cascade refrigeration mode; otherwise, determining the refrigeration mode of the liquid cooling system to be a compression refrigeration mode.
The control module 406 further includes: the energy-saving submodule is used for calculating the opening quantity of the fans when the refrigerating mode of the liquid cooling system is a normal refrigerating mode or a normal refrigerating and compression overlapping refrigerating mode, and controlling the operation of the fans according to the opening quantity of the fans; when the refrigeration mode of the liquid cooling system is a compression refrigeration mode or a normal cooling and compression cascade refrigeration mode, the starting number of the compressors is calculated, and the operation of the compressors is controlled according to the starting number of the compressors.
The specific manner in which the respective units and modules perform the operations in the apparatus of the above embodiments has been described in detail in the embodiments related to the method, and will not be described in detail here.
Example 3
Based on the liquid cooling system control device provided in the above embodiment 2, in a preferred embodiment 3 of the present invention, a liquid cooling system is further provided, as shown in fig. 1, and the liquid cooling system control device is also included, so as to control the system.
In the embodiment, the control scheme of the liquid cooling system is provided, the refrigeration system is provided with a normal cooling refrigeration mode, a compression refrigeration mode, a normal cooling mode and a compression cascade refrigeration mode, the refrigeration capacity parameter is adopted to accurately judge the refrigeration mode of the liquid cooling system, the problems that the refrigeration mode of the liquid cooling system can only be switched on and the judgment of the refrigeration mode is not accurate enough are effectively solved, meanwhile, the refrigeration capacity of the normal cooling mode and the compression cascade refrigeration mode is larger than that of a conventional compressor refrigeration mode and a normal cooling mode, the refrigeration capacity output range of the liquid cooling system is enlarged by the three refrigeration modes, different refrigeration demands are met, and the refrigeration operation range of the system is improved.
Example 4
Based on the liquid cooling system control method provided in the above-described embodiment 1, there is also provided in a preferred embodiment 4 of the present invention a storage medium containing computer-executable instructions for executing the liquid cooling system control method as described above when executed by a computer processor.
In the embodiment, the control scheme of the liquid cooling system is provided, the refrigeration system is provided with a normal cooling refrigeration mode, a compression refrigeration mode, a normal cooling mode and a compression cascade refrigeration mode, the refrigeration capacity parameter is adopted to accurately judge the refrigeration mode of the liquid cooling system, the problems that the refrigeration mode of the liquid cooling system can only be switched on and the judgment of the refrigeration mode is not accurate enough are effectively solved, meanwhile, the refrigeration capacity of the normal cooling mode and the compression cascade refrigeration mode is larger than that of a conventional compressor refrigeration mode and a normal cooling mode, the refrigeration capacity output range of the liquid cooling system is enlarged by the three refrigeration modes, different refrigeration demands are met, and the refrigeration operation range of the system is improved.
Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. This application is intended to cover any variations, uses, or adaptations of the application following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the application pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.
It is to be understood that the invention is not limited to the precise arrangements and instrumentalities shown in the drawings, which have been described above, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the invention is limited only by the appended claims.
Claims (10)
1. A liquid cooling system control method, comprising:
calculating the maximum refrigerating capacity of the liquid cooling system in different refrigerating modes; wherein, the refrigeration mode at least includes: a normal cooling refrigeration mode, a compression refrigeration mode, a normal cooling and compression cascade refrigeration mode;
obtaining target required refrigeration capacity of the liquid cooling system;
determining a refrigeration mode of the liquid cooling system according to the maximum refrigeration capacity and the target required refrigeration capacity, and controlling the operation of the liquid cooling system according to the refrigeration mode;
controlling operation of the liquid cooling system according to the refrigeration mode, including:
When the refrigeration mode of the liquid cooling system is the normal cooling refrigeration mode or the normal cooling and compression cascade refrigeration mode, calculating the opening quantity of fans, and controlling the operation of the fans according to the opening quantity of the fans;
and when the refrigerating mode of the liquid cooling system is the compression refrigerating mode or the normal cooling and compression cascade refrigerating mode, calculating the starting quantity of the compressors, and controlling the operation of the compressors according to the starting quantity of the compressors.
2. The method of claim 1, wherein calculating the maximum cooling capacity of the liquid cooling system in different cooling modes comprises:
Acquiring operation parameters of the liquid cooling system; wherein the operating parameters include at least: the operation parameters of the surface cooler of the liquid cooling system and the operation parameters of the compressor of the liquid cooling system;
And calculating the maximum refrigerating capacity of the liquid cooling system in the normal cooling mode according to the operation parameters of the surface cooler, and calculating the maximum refrigerating capacity of the liquid cooling system in the compression cooling mode according to the operation parameters of the compressor.
3. The method of claim 2, wherein the step of determining the position of the substrate comprises,
Calculating the maximum refrigerating capacity of the liquid cooling system in the normal cooling refrigerating mode according to the operation parameters of the surface cooler, wherein the maximum refrigerating capacity comprises the following steps: the method comprises the steps of obtaining the number a of the surface coolers, the water inlet and outlet temperature difference t 1 of the surface coolers and the heat capacity x of cooling liquid, and calculating the maximum refrigerating capacity Q1 of the liquid cooling system in the normal cooling refrigerating mode through the following formula: q1=k 1*(a*x*t1), where k 1 is a refrigeration coefficient in the normal cooling refrigeration mode;
calculating the maximum refrigerating capacity of the liquid cooling system in the compression refrigerating mode according to the operation parameters of the compressor, wherein the maximum refrigerating capacity comprises the following components: the number n of the compressors, the refrigerating capacity b of the single compressor and the outdoor environment temperature t 2 are obtained, and the maximum refrigerating capacity Q2 of the liquid cooling system in the compression refrigerating mode is calculated through the following formula: q2=k 2*n*(b* k3*t2), where k 2 is a cooling coefficient in the compression cooling mode, and k 3 is an outdoor environment temperature correction coefficient.
4. The method of claim 1, wherein obtaining a target demand refrigeration capacity of the liquid cooling system comprises:
acquiring the actual water inlet temperature and the target water outlet temperature of a cooling liquid main pipe of the liquid cooling system;
calculating the target required refrigerating capacity according to the actual water inlet temperature and the target water outlet temperature; wherein, the target required refrigeration capacity q=c×m×t 0, c is the specific heat capacity of the cooling liquid, m is the mass of the cooling liquid, and t 0 is the difference between the actual inlet water temperature and the target outlet water temperature.
5. The method of claim 1, wherein determining a cooling mode of the liquid cooling system based on the maximum cooling capacity and the target demand cooling capacity comprises:
Judging whether the maximum refrigerating capacity in the normal cooling refrigerating mode can meet the target required refrigerating capacity or not;
if yes, determining the refrigeration mode of the liquid cooling system as the normal cooling refrigeration mode;
otherwise, acquiring the outdoor environment temperature and the water inlet and outlet temperature difference of the liquid cooling system, and determining the refrigeration mode of the liquid cooling system according to the outdoor environment temperature and the water inlet and outlet temperature difference of the liquid cooling system.
6. The method of claim 5, wherein determining a cooling mode of the liquid cooling system based on the outdoor ambient temperature and the inlet and outlet water temperature difference of the liquid cooling system comprises:
Judging whether the outdoor environment temperature is smaller than a first preset temperature or not;
if so, determining the refrigeration mode of the liquid cooling system as the normal cooling and compression cascade refrigeration mode;
Otherwise, further judging whether the outdoor environment temperature is smaller than a second preset temperature, wherein the second preset temperature is larger than the first preset temperature;
When the outdoor environment temperature is not less than the second preset temperature, determining that the refrigeration mode of the liquid cooling system is the compression refrigeration mode;
And when the outdoor environment temperature is smaller than the second preset temperature, further judging the refrigeration mode of the liquid cooling system according to the water inlet and outlet temperature difference of the liquid cooling system.
7. The method of claim 6, wherein further determining a cooling mode of the liquid cooling system based on a difference in water inlet and outlet temperatures of the liquid cooling system comprises:
Judging whether the water inlet and outlet temperature difference of the liquid cooling system is larger than a preset temperature difference threshold value or not;
if so, determining the refrigeration mode of the liquid cooling system as the normal cooling and compression cascade refrigeration mode;
otherwise, determining the refrigeration mode of the liquid cooling system as the compression refrigeration mode.
8. A liquid cooling system control device, comprising:
the calculating module is used for calculating the maximum refrigerating capacity of the liquid cooling system in different refrigerating modes; wherein, the refrigeration mode at least includes: a normal cooling refrigeration mode, a compression refrigeration mode, a normal cooling and compression cascade refrigeration mode;
The acquisition module is used for acquiring the target required refrigeration capacity of the liquid cooling system;
the control module is used for determining a refrigeration mode of the liquid cooling system according to the maximum refrigeration capacity and the target required refrigeration capacity and controlling the operation of the liquid cooling system according to the refrigeration mode;
the control module further includes: the energy-saving submodule is used for calculating the opening quantity of the fans when the refrigerating mode of the liquid cooling system is the normal cooling refrigerating mode or the normal cooling and compression cascade refrigerating mode, and controlling the operation of the fans according to the opening quantity of the fans; and when the refrigerating mode of the liquid cooling system is the compression refrigerating mode or the normal cooling mode and the compression cascade refrigerating mode, calculating the starting number of the compressors, and controlling the operation of the compressors according to the starting number of the compressors.
9. A liquid cooling system according to claim 8, comprising a liquid cooling system control device.
10. A storage medium containing computer-executable instructions, which when executed by a computer processor are for performing the liquid cooling system control method according to any one of claims 1 to 7.
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| CN202410452174.5A CN118049768B (en) | 2024-04-16 | Liquid cooling system control method and device and liquid cooling system |
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| CN202410452174.5A CN118049768B (en) | 2024-04-16 | Liquid cooling system control method and device and liquid cooling system |
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