KR102206706B1 - Centralized cooling system of immersion type - Google Patents

Abstract

The present invention relates to a centralized cooling system of an immersion type and, more specifically, to a novel centralized cooling system of an immersion type including: a plurality of cooling chambers having a closed inner space which can be filled with cooling liquid so that heating units subject to be forced-cooled down are submerged; a heat exchange module for cooling the cooling liquid at a place spaced apart from the cooling chamber; an integrated transfer pipe for transferring the cooling liquid from the cooling chamber to the heat exchange module; and an integrated conveying pipe for conveying cooling liquid from the heat exchange module to each cooling chamber. Therefore, the present invention protects the heat generating unit from dust or dust particles, and has a low risk of operation noise and fire, as well as high energy efficiency and efficient use of space.

Description

Centralized cooling system of immersion type}

The present invention relates to a centralized liquid immersion cooling system, and to explain in more detail, a plurality of cooling chambers having an enclosed internal space capable of filling a cooling liquid so that heating units subject to forced cooling are immersed, and the cooling chamber Including a heat exchange module for cooling the coolant at a place spaced from the heat exchanger, an integrated transfer tube for transferring the coolant from the cooling chamber to the heat exchange module, and an integrated transfer tube for transferring the coolant from the heat exchange module to each cooling chamber. By being configured, it is possible to protect the heating unit from dust or dust, to reduce the risk of operating noise and fire, as well as to a new centralized liquid immersion cooling system that is energy efficient and efficient in space utilization.

Along with the development of the IT industry, large-scale IT infrastructures are being built to provide various IT services to public institutions and large corporations. For example, a server is installed to support file management, data storage, program operation, etc., or to share hardware resources such as fax, printer, and equipment, and a number of clients, i.e. computer terminals, are connected to these servers by LAN. Is installed. The server serves to connect the computer to the computer (to establish a network) and is equipped with a large amount of storage space. It is always available so that each computer can access and store necessary data, and also search or download the necessary data. It is kept in the ON state.

In addition, when the number of client terminals is more than several hundred, multiple servers should be deployed.If necessary, the file management is divided into a file server, printer control is a printer server, and external exchanges such as the Internet are divided into a communication server, each having different roles. Is also given. Since such a server generates a lot of heat from the CPU or GPU installed inside, a heat sink or cooling fan is installed to radiate such heat to the outside. However, if the server is overloaded and overheated, the heat sink or cooling fan may not sufficiently cool the CPU and GPU, and in this case, the server may malfunction or crash.

In order to solve this problem, in most Internet data centers, separate constant temperature and humidity equipment is installed and operated in a server room in which a server rack is installed. However, large-scale data centers require a large number of constant temperature and humidity equipment, and a large amount of cost and energy are consumed to operate them. In addition, as the CPU and GPU of the server are becoming more and more highly functional and highly integrated, the heat generation of IT devices is gradually increasing, so it is not easy to solve the cooling load of the server with the existing constant temperature and humidity facilities.

In addition to these computer servers, storage used in data centers, network switches, and batteries used in various energy storage systems (ESS) generate a lot of heat during operation. A separate cooling system must be installed to strongly cool this heat. Electrical devices that require separate forced cooling in the industrial operation process are referred to as “heating units” in the present invention.

Conventionally, systems that can more efficiently cool the heat generated by the heating unit have been introduced around large-scale data centers. For example, in Korean Patent Application Publication No. 10-2011-9848 (January 31, 2011), the temperature and humidity of the internal air and the external air of a data center are compared, and accordingly, external air is introduced into the interior or internal air is A data center cooling system suitable for circulating to cool the interior of the data center is introduced.

In addition, Patent Publication No. 10-2014-28335 (March 10, 2014) discloses that when overheating occurs in a number of servers installed remotely, the network is used to control the cooling of the server. A server cooling control system is introduced. However, these conventional server room cooling systems are mostly air-cooled devices, and because equipment for injecting cooling air into the server room must be installed and operated, energy consumption is large and space utilization is not efficient, and is particularly vulnerable to fire. There was a downside.

On the other hand, Patent No. 10-2031645 (October 07, 2019) introduces an immersion heat control device that can effectively prevent a fire that may occur due to heat emitted from the battery module of an ESS (Energy Storage System). . The immersion type heat control device includes a storage tank 100 in which a cooling solution F1 is stored so that a plurality of battery modules 10 are immersed therein, and the cooling solution F1 as shown in FIG. A structure including a circulation pipe 200 for circulating to the outside of the storage tank 100, a heat exchange module 300 for cooling the circulation pipe 200, and a circulation pump 400 installed in the circulation pipe 200 Consists of.

Inside the upper end of the storage tank 100, a cooling water pipe 500 for cooling and condensing the vapor of the cooling solution F1, and a cooling water pump circulating the cooling water F2 flowing through the cooling water pipe 500 ( 600) is installed. In addition, as the cooling solution F1, it is exemplified that hydrofluoro ether (HFE), fluoro ketone (FK), perfluorinated compound (PFC), or the like can be used.

Publication Patent No. 10-2011-9848 (January 31, 2011) Publication Patent No. 10-2014-28335 (March 10, 2014) Registered Patent No. 10-2031645 (October 07, 2019)

The immersion heat control device of FIG. 1 is designed for an energy storage device (ESS), and a heat exchange module 300 is integrally installed for each storage tank 100, and the heat exchange module 300 is a cooling fan. Since the circulation pipe 200 is cooled by introducing the external air (A1) using the 340, cooling efficiency and space utilization are not efficient, and there is a disadvantage of generating an operating noise from the cooling fan 340, etc. . Therefore, the liquid immersion heat control device of FIG. 1 has a limitation that is not suitable for use as a server system in a large-scale data center.

Accordingly, an object of the present invention is a new centralized liquid immersion cooling system that can protect the heating unit subject to forced cooling from dust or dust, reduces operating noise and risk of fire, and has high energy efficiency and efficient space utilization. Is to provide.

In the centralized liquid immersion cooling system according to the present invention, a stacking rack in which layers are stacked in a state in which a plurality of heating units subject to forced cooling are spaced apart from each other is installed, and the cooling liquid can be filled so that all the heating units are immersed A plurality of cooling chambers each having an enclosed inner space and each installed with a temperature sensor; A plurality of branch drain pipes each connected to each of the cooling chambers to discharge a part of the cooling liquid and each having a flow rate control valve installed thereon; An integrated transfer pipe provided with a circulation pump for collecting the coolant discharged to the branch drain pipe and transferring it to a location spaced apart from the cooling chamber; A heat exchange module for cooling the cooling liquid passing through the integrated transfer pipe; An integrated transfer pipe provided with a circulation pump for discharging the cooling liquid cooled in the heat exchange module and transferring it to the vicinity of the cooling chamber; A plurality of branch injection pipes respectively injecting the cooling liquid transferred through the integrated transfer pipe back into the cooling chamber and each having a flow control valve installed therein; The discharge of coolant to the cooling chamber by controlling the circulation pump installed in the integrated transfer pipe and the integrated transfer pipe, and valves installed in the branch drain pipe and branch injection pipe according to the temperature of the coolant detected by the temperature sensor installed in the cooling chamber. A control unit that independently controls the amount of injection and the injection amount; It characterized in that it is configured to include.

The centralized liquid immersion cooling system according to the present invention further includes a cooling liquid storage tank capable of draining or replenishing a cooling liquid in the cooling chamber, and a connection pipe is installed between the cooling chamber and the cooling liquid storage tank, respectively, and the The cooling liquid storage tank is characterized in that the cooling liquid supplement pipe is installed.

In addition, an integrated interface box is additionally installed on the outer surface of the cooling chamber, and the integrated interface box is a communication connection port that connects each communication with an external communication means one-to-one with respect to the heating units built in the cooling chamber. And at least one of a wireless transmitter and receiver is provided.

In addition, a central power supply device is additionally installed on the outer surface of the cooling chamber, and the central power supply device includes a power control switch that connects each power source to an external power source one-to-one for the heating units, and is supplied from the outside. It is characterized in that a power conversion device is installed that converts AC power to DC power of a voltage required for each heating unit and supplies it to a power control switch of the corresponding heating unit.

The centralized immersion cooling system according to the present invention collects a plurality of heating units separately and immerses them in a cooling chamber filled with a cooling liquid, preferably fluorinated ketone, so that the heating units are completely protected from dust or dust. In addition, there is an effect of having very high energy efficiency as well as reducing the risk of fire and operating noise generated in the process of operating the heating units.

In particular, the fluorinated ketone used as a cooling liquid in the present invention has an appearance and fluidity similar to that of water, but chemically has completely different properties from water, so a heating unit in which electric or electronic parts are mounted is used as a liquid. If the heating unit is removed even if left intrusive, it dries quickly without any functional obstacles or traces, so that the electric heating unit can be cooled very effectively.

In addition, the centralized liquid immersion cooling system according to the present invention has the advantage of easy space utilization because a heat exchange module for cooling the cooling liquid can be installed in a place spaced apart from the cooling chamber, for example, on the roof of a building or on a basement floor.

1 is a configuration diagram of a conventional immersion heat control device for an energy storage device (ESS),
2 is a configuration diagram of a centralized immersion type cooling system according to the present invention,
3 is a conceptual diagram of an integrated interface box 70 and a central power supply unit 80 connected to each heating unit 11 in the liquid immersion cooling system according to the present invention.

The centralized liquid immersion cooling system according to the present invention, as shown in the accompanying Figure 2, a plurality of cooling chambers 10, a branch drain pipe (20a), an integrated transfer pipe (20), a heat exchange module (30), integrated transport It consists of a pipe 40, a branch injection pipe 40a, and a control unit 50, and may additionally include a coolant storage tank 60, an integrated interface box 70, and a central power supply unit 80.

First, the cooling chamber 10 is a container shape each having a sealed internal space, and the inside of the cooling chamber 10 is a stacking rack 12 in which various heating units 11 to be subjected to forced cooling can be stacked in a state spaced apart from each other. ) Is installed, and the cooling liquid (Q) is filled so that all the heating units 11 provided on the loading rack 12 are immersed.

In the present invention, the heating unit 11 provided in the loading rack 12 includes a computer server, a storage used in a data center, a network switch, and an energy storage device (ESS). It may be any one or more of the batteries. In addition, although only three cooling chambers 10 are shown in FIG. 2 for convenience, the cooling chambers 10 may be installed in series or parallel in parallel with, for example, dozens or more at regular intervals.

In addition, as the cooling liquid Q, any one or more of HFE (hydrofluoro ether), FK (fluoro ketone), and PFC (perfluorinated compound) may be used, but it is preferable to use FK, that is, fluorinated ketone. The fluorinated ketone is a chemical substance synthesized by substituting fluorine for carbon in the molecule of the ketone, and the molecular formula is represented by'CF ₃ CF ₂ (O)CF(CF ₃ ) ₂ '. The fluorinated ketone is a colorless, odorless liquid, and its viscosity is almost the same as water, so it exhibits fluidity similar to that of water when poured into a container or poured out, but its specific gravity is 1.7 times heavier than water.

The chemical properties of fluorinated ketones have a freezing point of -108°C and a boiling point of 49°C, much lower than that of water. Therefore, it exists as a liquid at room temperature, but vaporizes quickly when the temperature rises slightly. The vapor pressure at room temperature is 12 times larger than that of water, and the latent heat of evaporation at room temperature is 25 times smaller than that of water. In addition, it has chemically stable properties due to fluorine, and since its dielectric strength is more than twice that of nitrogen, electricity does not pass through, and chemical reactions such as oxidation with the contacted substances do not occur.

In general, a fluorine compound has a very small surface tension and spreads well when it comes into contact with other objects. However, a fluorinated ketone also has a very low surface tension, so when it touches paper, it spreads without forming water droplets and soaks in. This is because fluoroketone has a very strong intramolecular binding force, but weak intermolecular bonding.

Unlike water, fluorinated ketones do not cause failure even if electronic products such as servers are immersed in it. One of the reasons is that fluorine, an element constituting this material, has stable properties, so it does not conduct electricity and does not cause reactions such as oxidation with the contacted material. Another reason is that its boiling point is 49℃, which is much more than water. Because it is low. Since water has a boiling temperature of 100°C, it takes a lot of time for wet items to dry completely at room temperature, but it takes less than a few minutes for items to dry out in a fluorinated ketone.

And when fluorinated ketones are sprayed at the fire site, they evaporate rapidly when they come into contact with flames or smoke, so they take away the heat and leave no traces on objects. Like this, fluorinated ketones have an appearance and fluidity similar to water, but chemically, they have completely different properties from water, so if you put the server in it, you can effectively cool the server and get a perfect dustproof effect. , It has the effect of fundamentally blocking fire. In addition, when the server is removed from the fluorinated ketone, the server is very convenient to use because it dries quickly without any obstacles or traces.

The cooling chamber 10 is provided with a plurality of branch drain pipes 20a for discharging a part of the cooling liquid Q, respectively, and the cooling liquid Q discharged to the branch drain pipe 20a is an integrated transfer pipe 20 It is transferred to the heat exchange module 30 through.

The branch drain pipe 20a is preferably connected to the upper portion of the cooling chamber 10 so as to discharge the coolant Q having a relatively high temperature in the cooling chamber 10. In addition, in the present invention, due to the integrated transfer pipe 20, the heat exchange module 30 can be installed at a location separated by a considerable distance from the cooling chamber 10 without spatial limitation, for example, on the roof of a building or on a basement floor.

The heat exchange module 30 functions to cool the coolant Q transferred through the integrated transfer pipe 20, for example, an air-cooled type for cooling the coolant Q by introducing external air, or an external coolant. It may be configured as a water-cooling method for cooling the cooling liquid Q by circulating it, or a mixed cooling method in which one or two or more of known cooling methods such as a gas type are mixed.

The cooling liquid (Q) sufficiently cooled while passing through the heat exchange module (30) is transferred to the branch injection pipe (40a) through the integrated transfer pipe (40), and then again injected into the cooling chamber (10). At this time, the integrated transfer pipe 40 is preferably installed in a direction parallel to the integrated transfer pipe 20, and the branch injection pipe 40a is preferably connected to the lower end of each cooling chamber 10. .

The control unit 50 includes a discharge amount of the cooling liquid Q discharged from the cooling chamber 10 according to the temperature of the cooling liquid Q stored in the cooling chamber 10 and the cooling liquid injected back into the cooling chamber 10 ( It controls the injection amount of Q).

According to a preferred embodiment of the present invention, a temperature sensor (S) is installed in the cooling chamber 10, respectively, and a flow control valve (V) is installed in the branch drain pipe 20a and the branch injection pipe 40a, respectively. The integrated transfer pipe 20 and the integrated transfer pipe 40 are each provided with a circulation pump P. Thus, the control unit 50 may be configured to control the driving of the flow control valve V and the circulation pump P according to the temperature of the coolant Q sensed by the temperature sensor S.

The centralized liquid immersion cooling system according to the present invention may further include a cooling liquid storage tank 60, and a connection pipe 61 is installed between the cooling chamber 10 and the storage tank 60, respectively. In addition, the storage tank 60 is provided with a cooling liquid supplement pipe 62 that can supplement the cooling liquid from the outside. The cooling liquid storage tank 60 stores a preliminary cooling liquid Q, so when the amount of the cooling liquid Q to be filled in the cooling chamber 10 is insufficient, each cooling chamber ( Coolant (Q) can be replenished with 10).

In addition, when the heating unit 11 or the loading rack 12 is repaired or replaced, all of the cooling liquid Q filled in the cooling chamber 10 through the connection pipe 61 is transferred to the storage tank 60. After draining with, the cooling chamber 10 can be opened to perform a desired operation. After the corresponding operation is completed, the cooling liquid Q may be injected into the cooling chamber 10 again.

In the cooling system according to the present invention, since all the heating units 11 are built in the cooling chamber 10, it is complicated and difficult to connect the heating units 11 to an external power supply and communication means, respectively. In order to solve this problem, an integrated interface box 70 may be installed outside the cooling chamber 10, respectively. As shown in FIG. 3, the integrated interface box 70 is provided with a communication connection port that connects the communication of the heating units 11 built in the cooling chamber 10 to an external communication means on a one-to-one basis, respectively. The communication connection port may be composed of an Ethernet port, a video port, a serial port, a USB port, and the like.

On the other hand, in accordance with the recent trend of increasing the size of the data center, in order to operate, maintain, and manage the server system, a number of ports and wires must be connected to the heating unit 11, respectively, and for this purpose, a large number of LAN wires or cables are required. It must be installed complicatedly.

In order to solve this problem, the integrated interface box 70 may additionally be provided with a wireless transceiver connected to the heating unit 11 in a one-to-one manner. Each of the wireless transceivers may be given a unique channel wirelessly connected to an external communication means. If such a wireless communication means is used, space utilization is easy, installation cost can be saved, and there is an effect of reducing operating manpower. In the integrated interface box 70, only one of the communication connection port and the wireless transceiver may be installed, or both may be installed.

In addition, a central power supply unit 80 may be additionally installed outside the cooling chamber 10, and the power of the heating units 11 is connected to an external power source in a one-to-one manner to the central power supply unit 80, respectively. Main power control switch can be installed. In addition, the central power supply unit 80 is provided with a power conversion device 81 that converts AC power supplied from the outside into DC power of the voltage required for each heating unit 11 and supplies each to the corresponding heating unit 11. It could be.

In general, the heating units 11 mostly use DC power. Therefore, the conventional heating unit 11 is provided with a power supply that converts AC power supplied from the outside into DC power, respectively. For example, in the case of data centers, separate power supplies are installed in servers, storage, and network switches, respectively, to convert and supply AC power of 90 to 240 V supplied from the outside to DC power such as 4 V, 12 V, 24 V, 48 V depending on the purpose. have. Some heating units 11 are also equipped with a plurality of individual power supplies. So, for example, in a data center with 100,000 servers, more than 100,000 individual power supplies must be installed.

These conventional individual power supplies have low power efficiency in the process of outputting power input to AC to DC due to device characteristics, and generate a lot of heat, so a fan must be installed to cool the heat. Therefore, the volume of each heating unit 11 is increased, noise is generated, and an air conditioning system capable of efficiently performing heat treatment must be installed.

The central power supply device 80 according to the present invention converts the AC power supplied from the outside by the power conversion device 81 into, for example, 4V, 12V, 24V, 48V DC power according to the characteristics of each heating unit 11 Then, it can be supplied to each of the power control switch of the heating unit (11). Accordingly, by removing the power supply device installed in the conventional heating unit 11 and providing DC power directly to the circuit, it is possible to reduce equipment installation cost and effectively utilize the facility space.

The central power supply device 80 may be independently installed inside or outside a data center, an energy storage system, or a server room.

(10) Cooling chamber (11) Heating unit
(12) Stacking rack (20a) Branch drain pipe
(20) Integrated transfer pipe (30) Heat exchange module
(40) Integrated transfer pipe (40a) Quarterly injection pipe
(50) control unit (60) coolant storage tank
(61) Connector (62) Coolant Supplement Pipe
(70) Integrated interface box (80) Central power supply
(81) Power converter (Q) coolant
(S) Temperature sensor (V) Valve
(P) pump

Claims (7)

A stacking rack is installed in which layers are stacked in a state in which a plurality of heating units subject to forced cooling are spaced apart from each other, and has a sealed internal space that can be filled with coolant so that all the heating units are immersed, and a temperature sensor is installed respectively A plurality of cooling chambers;
A plurality of branch drain pipes each connected to each of the cooling chambers to discharge a part of the cooling liquid and each having a flow rate control valve installed thereon;
An integrated transfer pipe provided with a circulation pump for collecting the coolant discharged to the branch drain pipe and transferring it to a location spaced apart from the cooling chamber;
A heat exchange module for cooling the cooling liquid passing through the integrated transfer pipe;
An integrated transfer pipe provided with a circulation pump for discharging the cooling liquid cooled in the heat exchange module and transferring it to the vicinity of the cooling chamber;
A plurality of branch injection pipes respectively injecting the cooling liquid transferred through the integrated transfer pipe back into the cooling chamber and each having a flow rate control valve installed therein;
The discharge of coolant to the cooling chamber by controlling the circulation pump installed in the integrated transfer pipe and the integrated transfer pipe, and valves installed in the branch drain pipe and branch injection pipe according to the temperature of the coolant detected by the temperature sensor installed in the cooling chamber. A control unit that independently controls the injection amount and the injection amount; It is composed including,
The heating unit stored in the cooling chamber is at least one of a server, a storage, a network switch, and a battery of an energy storage device (ESS), and the cooling liquid is a fluoro ketone (FK). ), a centralized immersion cooling system, characterized in that.
delete delete The method of claim 1, further comprising a cooling liquid storage tank capable of draining or replenishing the cooling liquid in the cooling chamber, a connection pipe is provided between the cooling chamber and the cooling liquid storage tank, respectively, and the cooling liquid is replenished in the cooling liquid storage tank. Centralized liquid immersion cooling system, characterized in that the tube is installed.
The communication connection according to claim 1, wherein an integrated interface box is installed on the outer surface of the cooling chamber, and the integrated interface box connects communication of the heating units built in the cooling chamber one-to-one with an external communication means. A centralized immersion cooling system, characterized in that at least one of a port and a wireless transceiver is provided.
The power control according to claim 1, wherein a central power supply is installed on the outer surface of the cooling chamber, and the central power supply connects the power of the heating units built in the cooling chamber to an external power in one-to-one. Centralized immersion cooling system, characterized in that the switch is installed.
The power converter according to claim 6, wherein the central power supply unit is provided with a power conversion device that converts externally supplied AC power into DC power of a voltage required for each heating unit and supplies it to the power control switch of the heating unit. Centralized immersion cooling system.

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