Data center cooling system

Abstract

A system for cooling a data center having a plurality of computer modules (10) with semiconductor components, which semiconductor components represent a heat source during operation, comprising: a cooling device for cooling the computer modules (10) by means of a coolant fluid circuit, wherein the cooling device comprises an adsorption cooling device (50) with an evaporator (V), a condenser (K) and one or more adsorption / desorption elements (Ads / Des) for the coolant fluid, wherein the condenser (K) has a thermal interface (51) for dissipating heat to a thermal reservoir (56), and a cold storage device (60) which is controllably thermally coupled to the adsorption cooling device (50) for buffering cold released by the adsorption cooling device (50).

Description

TECHNICAL FIELD OF THE PRESENT DISCLOSURE

[0001] The present disclosure relates to a system for cooling a data center. BACKGROUND OF THE INVENTION

[0002] Due to the high and constantly increasing demand, the need for computing power in data centers has increased significantly. The increasing digitalization of business and society, the rapid development of cloud computing, and, in recent years, the growing use of artificial intelligence (AI) and machine learning have played a major role. The development and application of AI and machine learning require enormous computing resources, especially for training AI models. These technologies have a massive impact on data centers because they require specialized hardware such as graphics processing units (GPUs) and tensor processors (TPUs), which are much more powerful than conventional microprocessors (CPUs), but also consume more power and generate more heat.

[0003] Data centers generate enormous amounts of heat due to their high computing power and the operation of thousands of servers, which must be efficiently dissipated to protect the hardware from overheating and ensure stable operation. There are various methods for cooling data centers, such as air cooling, water cooling, or immersion cooling, where servers or other IT components are directly immersed in a special, non-conductive coolant. The coolant efficiently dissipates the heat, reducing the need for air or water cooling.

[0004] The components in data centers, particularly servers, processors, and other electronic components, generate varying temperatures during operation. The exact temperature depends on the type of component, the workload, and the cooling methods. In general, components in data centers must not get too hot to avoid damage or performance degradation. Typical temperature ranges for processors (CPUs and GPUs) are between 30°C and 50°C when idle and 60°C to 70°C when fully loaded. In small data centers, the higher temperature range is typical. Other electronic components such as memory or network components operate at lower operating temperatures of approximately 30°C to 50°C.

[0005] Cooling data centers remains a major challenge, as it is critical for both performance and energy efficiency, as well as the carbon footprint of a data center. SUMMARY OF THE INVENTION

[0006] The invention is defined by the independent claims. Dependent claims describe further embodiments of the invention.

[0007] According to the invention, a system for cooling a data center is proposed, which has a plurality of computer modules with semiconductor components, which semiconductor components represent a heat source during operation, comprising: a cooling device for cooling the computer modules by means of a coolant fluid circuit, wherein the cooling device comprises an adsorption cooling device with an evaporator, a condenser, and one or more adsorption / desorption elements for the coolant fluid, wherein the condenser has a thermal interface for releasing heat to a thermal reservoir, and a cold storage device which is controllably thermally coupled to the adsorption cooling device for buffering cold released by the adsorption cooling device.

[0008] The invention is based on the combination of one or more adsorption chillers, which are ideally suited for cooling in the temperature range of 55°C to 70°C, with a device for storing or buffering cold, which can be used to handle power and / or temperature peaks. Maintaining a cold reserve enables savings in the design of the entire cooling system, allowing for a lower maximum output. Cold storage also makes it possible to respond to electricity price fluctuations and, by using stored cold, to reduce the cooling system's power consumption in the short term.

[0009] Preferably, the cold storage device is designed as a PCM cold storage device, which enables efficient cold storage within the specified temperature ranges. Preferably, the thermal reservoir of the adsorption cooling device is coupled to a second cold storage device.

[0010] Furthermore, the cold storage device can comprise a thermal building core storage, a geothermal storage, a liquid storage, and / or a local or district cooling network.

[0011] Preferably, the geothermal energy storage system, thermal building core storage system, liquid cooling storage system, and / or the local or district cooling network can be thermally coupled to the thermal reservoir and / or the adsorption cooling device depending on the outside temperature. Thus, for example, during winter operation, a significant portion of the cooling capacity can be provided by ambient cooling, further reducing the data center's energy consumption.

[0012] Furthermore, the adsorption / desorption elements of the adsorption cooling device can be thermally coupled to a solar thermal heating device for thermal support of the desorption process. This allows the data center's energy consumption to be further reduced through the use of solar energy.

[0013] Preferably, the adsorption / desorption elements of the adsorption cooling device are thermally coupled to the data center's computer modules, with the heat dissipated by the computer modules being used to desorb the coolant fluid. The temperature range of high-performance AI processors, above 55°C, is ideal for desorbing coolants such as water.

[0014] Preferably, the adsorption / desorption elements of the adsorption cooling device are thermally coupled to the computer modules of the data center by means of heat exchangers via a high-temperature cooling circuit, wherein the temperature of the heat exchange medium flowing back from the computer modules to the adsorption element Ads is at least 50°C, preferably at least 55°C, and more preferably at least 60°C.

[0015] Preferably, the adsorption and desorption elements of the adsorption cooling device can be cyclically thermally coupled to the computer modules of the data center for continuous cooling operation.

[0016] The evaporator of the adsorption cooling device can be thermally coupled to functional modules of the data center that have a lower operating temperature than the computer modules, such as memory or communication components.

[0017] The coolant fluid of the adsorption cooling device is preferably water.

[0018] The sorbent of the adsorption cooling device can be zeolite or silica gel.

[0019] The PCM material of the PCM storage can include water, saline solutions or paraffins.

[0020] The invention also relates to a data center comprising a cooling system according to one of claims 1 to 15. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a schematic representation of a first embodiment of a system according to the invention for cooling a data center. Fig. 2 shows a schematic representation of a second embodiment of a system according to the invention for cooling a data center. Fig. 2a shows a schematic representation of a variant of the Fig. 2 shows the inventive system for cooling a data center. Fig. 3 shows a schematic representation of a third embodiment of a system according to the invention for cooling a data center. Fig. 4 illustrates the storage of cold in the inventive system for cooling a data center according to Fig. 3. Fig. 5 illustrates the storage of cold in the inventive system for cooling a data center according to Fig. 3. Fig. 6 shows a schematic representation of a fourth embodiment of a system according to the invention for cooling a data center. Fig. Figure 7 illustrates a first sub-cycle of a known adsorption chiller. Fig. Figure 8 illustrates a second subcycle of a known adsorption chiller. DETAILED DESCRIPTION

[0021] Reference is made below to exemplary embodiments of the disclosure illustrated in the accompanying drawings. Wherever possible, the same reference numerals are used throughout the drawings to refer to the same or similar entities. Furthermore, the terms used in connection with a particular embodiment, e.g., the Fig. The features and technical effects illustrated and explained in Figure 1 also apply to all other embodiments, unless otherwise stated. Unless otherwise stated, features and effects of different embodiments can be combined as appropriate. Adsorption chillers

[0022] Adsorption chillers are thermally driven chillers. They use a solid sorbent, such as activated carbon, zeolite, or silica gel, to compress a refrigerant through a sorptive process. The sorbent is located in a device that alternately functions as an adsorber and desorber.

[0023] An adsorption chiller, as known from WO 2017 / 174235, is shown schematically in Fig. 7 and essentially consists of an evaporator V, an adsorber Ads, a desorber Des, a condenser K and a throttle D. Since two adsorbers / desorbers are provided, the cooling process can be operated continuously, ie without interruption.

[0024] The working medium, for example, water, is adsorbed onto a solid adsorbent in the adsorption device Ads. The resulting negative pressure causes the working medium to transform into a gaseous state in the evaporator V. The evaporator V absorbs heat from the environment (arrow "\N closed") and can therefore be used for cooling.

[0025] At the same time, the working fluid is expelled from the desorber Des by the addition of external heat (arrow "\N in"). The working fluid then enters the condenser K in a gaseous state and is liquefied there. The heat absorbed at the evaporator V, together with the heat supplied to the desorber Des, is released at the condenser K (arrow "\N out"). The working fluid then returns to the evaporator V in liquid form via a return line. This completes the working cycle of the adsorption chiller. The device thus operates as a heat pump, requiring no fans or other moving parts, allowing the adsorption chiller to operate very efficiently and with low maintenance.

[0026] If the adsorber Ads is saturated with the working medium, the system switches to the second part of the working cycle, which is Fig. 8 is illustrated.

[0027] Valve 2 is closed and valve 4 is opened, transforming the former adsorber (Ads) into the desorber (Des). At the same time, valve 1 is opened and valve 3 is closed, transforming the former desorber into the adsorber (Ads).

[0028] The working circuit formed between evaporator V, adsorber / desorber and condenser K contains section 55 (dashed line), in which the working medium is in gaseous form, and section 65, in which the working medium is in liquid form.

[0029] The working medium within the liquid semicircle 55 can be mixed with a suitable functional medium that can perform different tasks, such as reducing the vapor pressure of the working medium during the evaporation process in the evaporator V. PCM (Phase Change Material) Memory

[0030] A cold storage device based on phase change materials (PCM), also known as latent cold storage, uses the ability of substances to change between solid and liquid states when the temperature changes, for example, and to store or release heat through this phase change.

[0031] PCM cold storage systems utilize materials that transition from one state to another—for example, from solid to liquid—at a temperature within the appropriate range. During this phase change, a large amount of heat energy is absorbed or released without a significant change in the temperature of the material. This form of heat energy released during a phase transition is called latent heat. For example, when ice melts or water freezes, the temperature at atmospheric pressure remains fairly constant at 0°C, and boiling water has a constant temperature of 100°C.

[0032] The main advantage of this technique is that it stores latent heat - the heat that is absorbed or released during a phase change (for example, from solid to liquid) without directly changing the temperature of the material.

[0033] A commonly used material is paraffin, which melts at a temperature of approximately 20°C to 30°C. When used in a latent cold storage system, it can absorb and store excess heat as it transforms from a solid to a liquid state. When the temperature drops, it releases this stored heat as it transforms from a liquid back to a solid state.

[0034] The advantages of a PCM cold storage system include: - Energy efficiency: PCM cold storage systems offer high energy efficiency because they can store a large amount of thermal energy without significant temperature changes. This means they can provide constant cooling on demand without requiring constant refrigerant replenishment or consuming additional energy. - Space efficiency: This type of cooling requires less space and is less complex than conventional systems with evaporators or large chillers, since the stored energy is stored compactly in the material itself in the form of latent heat. - Continuous cooling: Since PCM cold storage systems can efficiently store heat over longer periods of time, they offer the possibility of uniform cooling without fluctuations, which is particularly advantageous in areas such as data centers, medical facilities or the food industry. - Sustainability: The use of phase change materials for cooling can reduce environmental impacts by requiring fewer mechanical cooling devices and using fewer refrigerants (which are often harmful to the climate).

[0035] Latent cold storage systems offer an effective and sustainable solution for cooling in various applications. Their ability to efficiently store and release large amounts of thermal energy makes them a promising technology. Embodiments of the invention

[0036] Fig. 1 schematically shows a first embodiment of a system according to the invention for cooling a data center.

[0037] The operation of the adsorption cooling device 50 corresponds in principle to that in Fig. 7 and Fig. 8 described adsorption cooling device.

[0038] The adsorption cooling device 50 according to Fig. 1 comprises an evaporator V, two adsorbers / desorbers Ads / Des, a condenser K and a throttle D. Since two adsorbers / desorbers are provided, the cooling process can be operated quasi-continuously, ie without interruption.

[0039] The two adsorbers / desorbers Ads / Des are connected via heat exchangers 31, 32 in a cooling circuit to the heat exchanger 11 of a computer module 10, which contains, for example, the high-performance processors (CPUs, TPUs, or GPUs) of an AI data center, which dissipate large amounts of heat at full load. This is preferably a high-temperature cooling circuit in which the heat dissipated by the processors is used to effect the desorption of the working medium (preferably water) in the circuit of the adsorption cooling device 50. The flow temperature of the high-temperature cooling circuit 31, 32, 11 is, for example, at least 60°C, and the return temperature is, for example, at least 55°C. This allows, on the one hand, the processors of the computer module 10 to be kept at a constant temperature, and, on the other hand, the desorption of the working medium of the adsorption cooling device 50 to be carried out efficiently.

[0040] The evaporator V, which releases cold, is connected to another functional module 20 of the data center via a cooling circuit comprising the heat exchangers or thermal interfaces 21, 41. This functional module 20 contains electronic components such as memory elements or network components that have a lower operating temperature (for example, 30°C to 45°C or even 18°C to 23°C) than the processors of module 10. The cooling circuit 21, 41 is thus a low-temperature cooling circuit. The return temperature from module 20 is, for example, 25°C, and the flow temperature to the module is, for example, 20°C or 15°C.

[0041] Cooling circuit 21, 41 has a valve-controlled branch to the heat exchanger 61 of a cold storage device 60, which is located in the Fig. 1 is designed as a PCM cold storage or latent cold storage, which - as explained above - stores the cold by means of a phase transition of a suitable cold storage material such as water, salt solutions or paraffins.

[0042] In the condenser K, the working medium condenses, releasing heat which is transferred to a cold reservoir 56.

[0043] The working circuit formed between evaporator V, adsorber / desorber and condenser K contains a section 55 (dashed line) in which the working medium is in gaseous form and a section 65 in which the working medium is in liquid form.

[0044] The working medium within the liquid semicircle 55 can be mixed with a suitable functional medium that can perform different tasks, such as reducing the vapor pressure of the working medium during the evaporation process in the evaporator V.

[0045] Fig. Figure 2 shows a schematic representation of a second embodiment of a system according to the invention for cooling a data center. This system additionally includes a solar thermal heating device ST, which can be coupled to the respective desorber to support the desorption process and can be used for further energy savings.

[0046] Fig. 2a shows a variant of the embodiment of the Fig. 2. Automatic parallel and series connection within the adsorption cascade 31a, 32a enables consistent return temperatures depending on the solar energy available. For large temperature differences dT, the elements of the adsorption cascade are connected in series, and for small temperature differences, they are connected in parallel.

[0047] Fig. 3 shows a schematic representation of a third exemplary embodiment of a system according to the invention for cooling a data center. This system has a second cold storage device 70 in which the cold is stored, for example, in the concrete core of a building or in a geothermal energy storage system, as disclosed, for example, in DE10 2022 116 248 B1. Alternatively, a liquid storage device and / or a local or district cooling network can also be used for cold storage. The second cold storage device 70 is thermally coupled to the cold reservoir 56 and / or the cold reservoir 57 and can store cold for recooling the adsorber Ads and / or the condenser K, particularly during the cold season.

[0048] The functioning of the inventive system for cooling a data center is explained below using the Fig. 2 to 5 explained.

[0049] As in Fig. As shown in Figure 2, the working medium, for example, water, is adsorbed onto a solid adsorbent in the adsorption device Ads. As a result, the working medium transforms into a gaseous state in the evaporator V. The evaporator V absorbs heat from the functional module 20 and uses it to operate the low-temperature cooling circuit 21, 41, which cools the functional module 20 of the data center. The heat flow from the functional module 20 to the evaporator V is symbolized by the arrow "W."

[0050] At the same time, the working fluid is expelled from the desorber Des by supplying external heat (arrow "W") from the processor module 10 via the high-temperature cooling circuit 11, 31, 32 and / or from the solar thermal heater ST. The working fluid then reaches the condenser K in a gaseous state and is liquefied there. The working fluid releases the heat absorbed at the evaporator together with the heat supplied at the desorber Des (arrow "W") at the condenser K, which is then transferred via a heat exchanger 51 to a cold reservoir 56 formed, for example, by a water tank or the like. The working fluid then returns to the evaporator V in liquid form via a return line 65. This completes the working cycle of the adsorption heat pump.

[0051] If the adsorber Ads is saturated with the working medium, the system switches to the second part of the working cycle, which is Fig. 4 is illustrated.

[0052] By opening or closing the valves shown, as shown in the Fig. 2 explains the transition from the previous adsorber Ads to the desorber Des and vice versa. This also reverses the heat flow in the high-temperature cooling circuit 11, 31, 32, as again illustrated by the arrows "W" and "K."

[0053] If, for example, the return temperature in the low-temperature cooling circuit 21, 41 falls below a certain level, because, for example, the entire cooling capacity of the evaporator V is not required, part of the generated cold can be stored efficiently and space-savingly in the PCM cold storage, as in Fig. 4 is schematically illustrated. Conversely, if the required cooling capacity of the cold reservoir 56 is insufficient, cold can be "extracted" from the PCM cold storage unit 60 via the heat exchanger 61. This additional cooling capacity, which can be accessed from the PCM cold storage unit as needed, allows the performance and thus the costs of the entire cooling system to be reduced. Furthermore, the cooling system's capacity can be reduced even in the event of short-term increases in electricity prices, and conversely, the cold storage unit can be refilled during periods of low electricity prices.

[0054] Here, Fig. 4 schematically shows the storage of cold (arrow “K”) in the PCM cold storage 60 and Fig. 5 the extraction of cold (arrow “K”) from the PCM cold storage 60 in order to support the cooling of the functional module 20 and thus increase the cooling capacity of the overall system.

[0055] Fig.Figure 6 shows the function of the second cold storage unit 70, which can be used, in particular, in "winter operation" to cool the functional module 20 and / or the cold reservoirs 56 and 57. Depending on the outside temperature, ambient cooling is thermally coupled to the cold reservoirs 56 and 57 and / or directly to the heat exchanger 21 of the functional module 20 by means of the building core storage unit, liquid cold storage unit, and / or the local or district cooling network. As a result, a significant portion of the cooling capacity can be provided by ambient cooling during winter operation, for example, enabling a reduction in the cooling energy consumption of the data center. In summary, the system according to the invention enables the efficient cooling of a data center, such as a K1 data center.The high-temperature waste heat from the high-performance components can be efficiently used to operate the adsorption cooling device, and the efficient PCM cold storage enables a reduction in the maximum cooling capacity specification and thus the costs of the overall cooling system by buffering and recovering cooling capacity during peak load times, without jeopardizing the 100% availability of the data center. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] WO 2017 / 174235

[0023] DE 10 2022 116 248 B1

[0047]

Claims

[1] System for cooling a data center, which has a plurality of computer modules (10) with semiconductor components, which semiconductor components represent a heat source during operation, comprising: a cooling device for cooling the computer modules (10) by means of a coolant fluid circuit, wherein the cooling device comprises an adsorption cooling device (50) with an evaporator (V), a condenser (K) and one or more adsorption / desorption elements (Ads / Des) for the coolant fluid, wherein the condenser (K) has a thermal interface (51) for dissipating heat to a thermal reservoir (56), and a cold storage device (60) which is controllably thermally coupled to the adsorption cooling device (50) for buffering cold released by the adsorption cooling device (50). [2] The system of claim 1, wherein the cold storage device (60) comprises a PCM (phase change material) cold storage. [3] The system of claim 1 or 2, wherein the thermal reservoir (56) of the adsorption cooling device (50) is thermally coupled to a second cold storage device (70). [4] System according to claim 3, wherein the second cold storage device (70) comprises a geothermal storage, a thermal building core storage, a liquid cold storage, and / or a local or district cooling network. [5] System according to claim 4, wherein the geothermal storage, thermal building core storage, liquid cold storage, and / or the local or district cooling network can be thermally coupled to the thermal reservoir (56) and / or the adsorption cooling device (50) depending on the outside temperature. [6] System according to one of claims 1 to 5, wherein the adsorption / desorption elements (Ads / Des) of the adsorption cooling device (50) are controllably thermally coupled to a solar thermal heating device (ST) for thermally supporting the desorption process. [7] System according to one of claims 1 to 6, wherein the adsorption / desorption elements (Ads / Des) of the adsorption cooling device (50) are thermally coupled to the computer modules (10) of the data center, wherein the heat emitted by the computer modules (10) is used to desorb the coolant fluid. [8] System according to claim 7, wherein the adsorption / desorption elements (Ads / Des) of the adsorption cooling device (50) are thermally coupled to the computer modules (10) of the data center by means of heat exchangers (11, 31, 32) via a high-temperature cooling circuit, wherein the temperature of the heat exchange medium flowing back from the computer modules (10) to the adsorption element Ads is at least 50°C, preferably at least 55°C, and more preferably at least 60°C. [9] System according to claim 7 or 8, wherein for continuous cooling operation at least two adsorption and desorption elements (Ads / Des) of the adsorption cooling device (50) can be cyclically thermally coupled to the computer modules (10) of the data center. [10] System according to one of claims 1 to 9, wherein the adsorption / desorption elements (Ads / Des) of the adsorption cooling device (50) have an adsorption cascade 31a, 32a which can be switched between series and parallel connection depending on the temperature. [11] System according to one of claims 1 to 10, wherein the evaporator (V) of the adsorption cooling device (50) is thermally coupled via a low-temperature cooling circuit to functional modules (20) of the data center which have a lower operating temperature than the computer modules (10). [12] System according to claim 11, wherein the functional modules (20) contain memory components and / or network components of the data center. [13] The system of any one of claims 1 to 12, wherein the coolant fluid of the adsorption cooling device (50) is water. [14] System according to one of claims 1 to 13, wherein the sorbent of the adsorption cooling device (50) is zeolite or silica gel. [15] System according to one of claims 1 to 14, wherein the PCM material of the PCM cold storage (60) contains water, salt solutions or paraffins. [16] System according to one of claims 1 to 15, wherein the data center is a Kl data center and the semiconductor components of the computer modules are GPU or CPU chips configured for Kl applications. [17] Data center comprising a cooling system according to one of claims 1 to 16.

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