Cooling of an electronic component

Abstract

A cooling device (1) for cooling at least one electronic component (3) is specified, wherein the cooling device (1) comprises a system (10) for an Organic Rankine Cycle process, wherein this system (10) comprises a pump (11), an evaporator (12), an expansion turbine (13) and a condenser (14) and is designed for operation with an organic working medium (M) in a closed circuit, wherein the evaporator (12) has a heat sink (20) made of a highly thermally conductive material, which is thermally coupled to the component (3) to be cooled and has at least in some areas a channel structure (21) for passing the working medium (M) through it, wherein the expansion turbine (13) comprises a shaft (30) which is torque-transmittingly coupled to a generator (G) for generating electrical energy.Furthermore, a method for cooling at least one electronic component (3) using an Organic Rankine Cycle process is specified, wherein such a cooling device (1) is used.

Description

The present invention relates to a cooling device for cooling at least one electronic component, in particular a microprocessor in a data center. The invention further relates to a method for cooling such a component.As digitalization increases, the size and number of data centers are growing widely worldwide. These data centers typically have a high energy consumption and thus also a high cooling requirement. Such data centers are also referred to as data centers and each have a multiplicity of computers with corresponding processors (computing units). These processors and also other electronic and electrical components of the data center must be cooled during operation in order to avoid overheating and thermal damage to the components. The waste heat produced in this case is present at a comparatively low temperature level of below 50° C. and in some cases even below 30° C. The low temperature level makes it difficult to use the waste heat, so that it is usually supplied to the cooler ambient air of the data center and / or to a liquid cooling medium without further energy use taking place.Within the scope of the energy law of the European Union (in particular the renewable energy guidelines RED II: 2018 / 2001 and RED III 2023 / 2413 and the energy efficiency guideline EED: 2012 / 27 / EU), a reduction in the demand for fossil energy carriers and an increase in the energy efficiency of data centers are prescribed. For this purpose, it is necessary to reuse the waste heat occurring during the cooling of the processors.In some data centers, some of the waste heat is bound in a cooling water and thus emitted to a district heating network. However, the total amount of heat usage is nevertheless low, since suitable consumers for the low-temperature heat provided are often not present at the suitable location and / or at the suitable time. Thus, there remains a need for ways to continue to utilize the thermal energy released during operation of electronic devices.It is therefore an object of the invention to specify a cooling device which enables efficient further use of the thermal energy released during operation of an electronic component. A further object is to specify a corresponding cooling method.These objects are achieved by the cooling device described in claim 1 and the method described in claim 12.The cooling device according to the invention is designed for cooling at least one electronic component and in particular also a plurality of electronic components. This cooling device comprises a plant for an organic rankine cycle process. This plant comprises a pump, an evaporator, a expansion turbine and a condenser and is designed for operation with an organic working medium in a closed circuit. The evaporator comprises a cooling body made of a highly heat-conducting material, which is thermally coupled to the component to be cooled and has a channel structure for conducting the working medium through at least in a partial region. The expander turbine includes a shaft that is torque-transmittingly coupled to an electric power generator.An organic Rankine cycle process is understood here to mean a process in which a stress relief turbine is operated with an organic working medium. The organic working medium is circulated in a closed circuit, i.e. after passing through the expansion turbine, compressed again and fed back to the expansion turbine. The expansion turbine is operated with gaseous working medium, i.e. it is a steam turbine. The gaseous working medium is introduced into the expansion turbine at a comparatively high pressure and expanded to a lower pressure within the expansion turbine. During this expansion, a portion of the heat of the working medium is converted into mechanical work of a turbine shaft, and the temperature of the working medium falls accordingly. After passing through the expansion turbine, the cooler and expanded working medium is introduced into the condenser. The condenser is a sub-element of the plant in which the working medium can be liquefied again. This can be effected in particular with further dissipation of heat to a cooling medium located outside the closed circuit, for example with heat being dissipated to an ambient air or a cooling water. After passing through the condenser, the liquid working medium is compressed to a comparatively higher operating pressure by means of the pump and is conveyed from the pump into the following evaporator. The evaporator is a partial element of the plant in which the working medium can be evaporated again, with absorption of heat from the environment. According to the present invention, this heat absorption takes place at least partially from the electronic component to be cooled. For this purpose, the evaporator has a cooling body made of a highly heat-conducting material, which is thermally coupled to the component to be cooled. The "highly heat-conducting" material of the heat sink is in particular a material having a thermal conductivity of at least 100 W / (m·K), such as copper or aluminum, for example, or an alloy with one of these metals. The cooling body can be designed, for example, in the form of a plate, in order to form a large-area contact surface with the component to be cooled with a comparatively small volume. The cooling body has, at least in partial regions, a channel structure for conducting the working medium through, and it can therefore be flown through by the working medium. This "passing through" of the working medium takes place overall within the scope of the closed circuit. In other words, the channel structure as a whole connects a media inlet of the evaporator to a media outlet of the evaporator and is otherwise fluidically encapsulated with respect to the external environment. The channel structure may comprise one or more such through channels. Advantageously, a plurality of channels is present. It is essential within the scope of the present invention that the present channels allow efficient heat transfer from the electronic component to the organic working medium, whereby the working medium can be evaporated while absorbing heat. The amount of heat absorbed here is substantially higher than the amount of heat emitted in the capacitor. The working medium evaporated in the evaporator is introduced again into the expansion turbine, whereby the circuit closes. The pump, the evaporator, the expansion turbine and the condenser are therefore designed in particular to be flowed through in the stated sequence in a closed circuit by the working medium. Optionally, further sub-elements of the system can be arranged therebetween.Overall, the described organic Rankine cycle process represents a modification or further development of the classic Clausius-Rankine cycle process, wherein an organic working medium is used instead of the water or water vapor present there. Accordingly, the operating pressures and operating temperatures in the individual regions of the process are adapted to the organic working medium used in each case.The generator serves for generating electrical energy, wherein "generation" is understood here to mean the conversion of another energy form into electrical energy. This other form of energy is here the mechanical energy of the rotational movement of the shaft, which is coupled to the generator in a torque-transmitting manner. The generator for generating the electrical energy can be designed or considered as part of the cooling device according to the invention, but it can alternatively also be located outside the cooling device. In connection with the invention, it is only important that the mechanical energy provided by the expansion turbine can be converted overall into electrical energy. In this way, the heat dissipated by the electronic component is partially converted into mechanical energy and subsequently into electrical energy. This allows further use of the waste heat of the component, wherein, with a suitable design of the parameters of the organic rankine cycle (in particular with a suitable selection of the working medium, the delivery pressure of the pump and the line cross sections used), a good efficiency can be achieved even at a comparatively low temperature level of the component. Overall, the invention thus contributes to increasing the energy efficiency during the operation of electronic components.The method according to the invention serves for cooling at least one electronic component with an organic rankine cycle process, wherein a cooling device according to the invention is used and wherein the method comprises the following steps: a) conveying liquid working medium into the evaporator by means of the pump, b) evaporating the working medium in the evaporator while absorbing heat from the electronic component, c) expanding the working medium in the expansion turbine while converting heat into mechanical energy and while generating electrical energy by the generator coupled to the shaft of the expansion turbine in a torque-transmitting manner, d) liquefying the working medium in the condenser while releasing heat to a cooling medium located outside the closed circuit and returning the liquid working medium to step a).The advantages of the cooling method according to the invention result analogously to the above-described advantages of the cooling device according to the invention.Advantageous embodiments and further developments of the invention are evident from the claims dependent on claims 1 and 12 and from the following description. The described embodiments of the cooling device can also be realized in the method, and vice versa.Generally advantageously, the component to be cooled can be a processor in a data center. In particular, a plurality of such processors (and optionally further components of the data center) can be cooled in the described manner. When data centers are operated, large total amounts of heat are typically released, so that the invention offers particularly great advantages when used in a data center. Also, investment in a comparatively complex organic Rankine cycle plant is particularly worthwhile if large amounts of heat are thus recovered. The cooling can be effected by thermal coupling to the semiconductor chips of the respective processors and / or further electronic components. The operating temperatures of such semiconductor chips should generally preferably be kept in a range below 95° C., which is possible without problems with the cooling according to the invention.If a total of a plurality of electronic (and optionally also further) components are cooled by the cooling device, a separate evaporator can be provided for the respective component according to a first embodiment variant. However, an evaporator can in principle also be designed for cooling a group of components and be thermally coupled to this plurality of components. The medium line can branch fluidically after the pump into a plurality of lines in order to feed a plurality of such evaporators with working medium. However, a plurality of pumps can also be provided, in particular if the number of evaporators present is particularly large. Then, a pump may feed either a single evaporator or a group of evaporators with working medium.According to a preferred embodiment, the cooling device is filled with an organic working medium in the ready-to-use state. This working medium is or comprises in particular a first medium component which is a fluorinated organic compound. In general, the working medium can also be a mixture of a plurality of medium components. The fluorinated organic compound can generally be a perfluorinated or else a partially fluorinated organic compound. It can be selected in particular from the following list of compound classes:a hydrofluoroolefin,an aliphatic saturated hydrofluorocarbon,a hydrofluoroether or perfluoroether,a fluorinated ketone, in particular a perfluorinated ketone.Alternatively, non-fluorinated (in particular non-halogenated) hydrocarbons can also be used. However, these are frequently more readily combustible in comparison with the fluorinated compounds and sometimes have relatively high greenhouse potentials.The aforementioned compound classes each contain one or more compounds which have particularly advantageous properties as working medium for an organic rankine cycle in a temperature range relevant for component cooling. The properties which are particularly relevant in this context are good environmental compatibility and suitable values for the boiling temperature, the enthalpy of vaporization, the vapor pressure, the thermal conductivity and the specific heat capacity (the last values in each case at the relevant operating temperature). In addition, low electrical conductivity and high dielectric strength are advantageous when the working medium comes into direct contact with electronic or electrical components.The organic working medium particularly advantageously comprises one or more compounds from the following list:1,3,3,3-tetrafluoroprop-1-ene,1,1,1,3,3-pentafluoropropane,methoxyheptafluoropropane,methoxynonafluorobutane,ethoxynonafluorobutane,dodecafluoro-2-methylpentan-3-one.1,3,3,3-tetrafluoroprop-1-ene is a hydrofluoroolefin for medium operating pressures, which is also sold under the name R1234ze and has a comparatively low greenhouse potential. 1,1,1,3,3-Pentafluoropropane is an aliphatic saturated fluorocarbon, also referred to as R245fa, whose boiling point and vapor pressure curve are in the appropriate range. Methoxyheptafluoropropane is also referred to as HFE-7000, methoxynonafluorobutane is also referred to as HFE-7100, and ethoxynonafluorobutane is also referred to as HFE-7200. These three compounds are particularly suitable hydrofluoroethers having low electrical conductivities and suitable boiling points. Dodecafluoro-2-methylpentan-3-one is a perfluorinated ketone, also sold under the names Novec 649 and Novec 1230. In addition to the advantageous thermodynamic properties, this compound has a particularly low greenhouse potential. Some of the compounds mentioned may have a plurality of isomers which may be used either separately or in a mixture.Generally advantageously, the organic working medium can be characterized by one or more of the following properties:a boiling temperature at normal pressure in the range from -20° C. to 80° C., preferably from 10° C. to 70° C. and particularly preferably from 25° C. to 60° C.,a greenhouse potential, based on a time horizon of 100 years, below 1200, preferably below 100 and particularly preferably below 1,a specific electrical resistance above 10 8 ohm·cm,an electrical breakdown strength above 10 kV / mm,an enthalpy of vaporization greater than 50 kJ / kg, in particular in the range between 50 kJ / kg and 500 kJ / kg,a vapor pressure at 80° C. in the range from 100 kPa to 1 MPaa specific heat capacity in the range of 950 J / (K·kg) to 1500 J / (K·kg)Not only in the case of the vapor pressure, but also in the case of the other physical properties, the stated values should definitely apply at a temperature of 80° C., since this is a typical operating temperature in the cooling of electronic components. By "normal pressure" is meant here a pressure of 1.01325 bar.According to a further generally advantageous embodiment, the working medium in the evaporator region is thermally coupled to the electronic component to be cooled either directly or via one or more separating walls and / or separating layers of a total thickness of at most 3 mm and preferably at most 1 mm. In other words, the working medium has a distance of at most 3 mm from the electronic component to be cooled in a partial region of the evaporator. The aforementioned distance is to be understood in particular as the distance between the working medium and a semiconductor chip of the electronic component. In the case of a "direct" coupling, the working medium is in direct contact with a semiconductor chip of the component, it can therefore directly rinse around the semiconductor chip. This variant can be used in particular if the heat sink of the evaporator is integrated into a chip housing of the semiconductor chip or is connected to a naked chip. Alternatively, the semiconductor chip can have a separate housing, and the heat sink can be in direct thermal contact with this chip housing, i.e. contact it and / or be coupled to it via a heat-conducting paste. Here too, the material thickness between semiconductor chip and working medium is advantageously limited to the said distance in order to ensure a thermal connection that is as tight as possible. At least one of the separating walls and / or separating layers can preferably be designed to be electrically insulating in order to limit an electrical interaction between the semiconductor chip and the working medium.Generally advantageously, the heat sink of the evaporator can be formed from a metallic material, for example from copper or aluminum or an alloy with such metals. The cooling body with its internal channel structure can be formed in particular by an additive manufacturing method. It can have one or advantageously a plurality of channels for transporting the working medium. The media-conducting channels of the channel structure can have, for example, an average channel diameter between 10 μm and 1000 μm, preferably between 30 μm and 500 μm. With such a dimensioning, the channels can also be advantageously suitable for capillary transport of liquid working medium.The structure of the media channels can in principle be formed in different ways. Thus, according to a first embodiment variant, a partial region of the cooling body can be designed as an open-pored metallic foam, so that a plurality of continuous channels extend between the pores. The term "open-pored metallic foam" is understood here to mean a structure which has a high surface area to volume ratio and in the process has an open porosity. The term foam is not, however, considered in the context as it is used in the gaseous foaming of a substance. Rather, this is understood to mean all open-pore structures which, in this case, can be formed in particular monolithically together with a wall element of the cooling body in an additive manufacturing method. Thus, for example, when using a powder bed-based method, the open porosity can be influenced in a targeted manner by the grain size and grain shape of the powder used and by the further process parameters (e.g. the local heat input during sintering or melting). Alternatively, the media channels can also be formed by defined channel elements. A "defined channel element" is to be understood here as a geometric element which does not randomly form at a specific point in the course of the production process, but which has been defined in the course of the geometric design, which has thus been specified, for example, as an element in the CAD design. The channel structure of the condenser can in principle be configured in a similar manner to the additively manufactured "capillary structure" of the evaporator-condenser arrangement which is disclosed in the patent application EP 3736519 A1. In particular, the channel structure can be configured similarly to the capillary structure in the evaporator region there. The cooling body can optionally also have a gas space in addition to the channel structures in which liquid working medium can be transported to the evaporation region. Such a separate gas space is fluidically coupled to the media channels and serves to receive evaporated working medium and to conduct it to the media outlet of the evaporator.According to an advantageous embodiment of the condenser, the latter can be thermally coupled to an external cooling medium located outside the closed circuit. This has the effect, in particular, that the organic working medium can be liquefied in the condenser with the emission of heat to this external cooling medium. This external cooling medium can be, for example, an ambient air or a cooling water. Alternatively or additionally, an additional buffer medium (cold accumulator) can be used as external cooling medium. This buffer medium can in turn be thermally coupled to an ambient air or a cooling water. The buffer medium can thus serve to compensate for time-of-day variations in the ambient air and thus to bring about a more uniform heat transfer in the condenser. The buffer medium can also be a fluid cooling medium, which, however, in contrast to ambient air or an incoming cooling water, can be present in particular in a closed container and therefore does not have to be supplied continuously. Alternatively or additionally, a solid material can also be used as buffer medium. In general, the amount of heat emitted in the condenser to the external cooling medium is significantly less than the amount of heat absorbed by the working medium in the evaporator.The cooling device can advantageously have an additional regenerator which is designed to transfer thermal energy from the working medium exiting from the expansion turbine to the working medium exiting from the pump. In other words, with such an optional circulating-internal heat exchanger, a portion of the residual heat from the expanded, gaseous working medium can be used for preheating the condensed and compressed working medium. In particular, this preheating takes place before entry into the evaporator. By preheating the liquid working medium under pressure, the evaporation in the evaporator can be assisted (depending on the choice of working medium and the temperature and pressure conditions) and the energy efficiency overall can be increased.Particularly advantageously, the cooling device can have a plant for a plurality of cycle processes. The corresponding plurality of media circuits can be designed for cooling a plurality of electronic components, wherein these components can be cooled in particular to different operating temperatures. The individual medium circuits can be fluidically separated from one another with respect to the respective working medium. Thus, in general, two or more separate medium circuits can be present, wherein in principle the same or different working media can be used. It is only important that an organic working medium is present in at least one of the medium circuits present, that is to say that during operation at least one organic Rankine cycle process takes place in the plant. The plurality of media circuits can be configured in particular similarly to that shown on page 12 of the paper "How is produced from geothermal heat electricity" by Matthias Gerwe (3rd North German Geothermal Tag on 28.10.2010, available at https: / / www.lbeg.Niedensaxis.de / download / 52210). In contrast to the diagram there, only the coupling of the two circuits by the warm delivery medium delivered from the earth is dispensed with, since instead electronic components present in each case in solid form bring about the heat input into the evaporator region. The fluidically separated circuits of the respective working media drive in each case an associated turbine, wherein two such turbines can be coupled in a torque-transmitting manner via a common shaft in a similar manner to the publication by M. Gerwe. Alternatively or additionally to this mechanical coupling, there may optionally also be a further thermal coupling of the fluidically separated medium circuits. Thus, for example, the working medium of one circuit can be coupled to the working medium of another circuit by a heat exchanger, in particular in order to bring about (similarly to the optional regenerator of the simple embodiment) a cooling of the expanded working medium of a first circuit with simultaneous preheating of the liquefied working medium of a second circuit. Generally, and regardless of the precise design of the working media, temperature levels, and optional thermal coupling, the multiple media circuit embodiment is advantageous for achieving cooling of multiple elements to different temperature levels at overall high energy efficiency.According to a further advantageous embodiment, the cooling device can be designed for cooling and / or heating at least one further element or medium with the same working medium. This further element or medium can be selected in particular from the following list:an internal air of a data center,a heating or cooling fluid for an interior of a building,a transformer, an electrical line or another electrical component of a power distribution installation.The building can in particular be a building of a data center, and the energy distribution installation can also be part of a data center or at least be designed to supply energy to a data center.According to a particularly advantageous configuration of the cooling method, the electrical energy provided by the generator can be used at least partially for the operation of the at least one electronic component. In this way, some of the waste heat can contribute to reducing the external electrical energy requirement. When cooling electronic components in a data center, the electrical energy can generally be used locally within the data center, that is to say for a plurality of electronic components and / or other electrical components in the data center. Thus, in particular during operation of a data center, the overall energy efficiency can be increased.According to a further generally advantageous embodiment of the method, the delivery of liquid working medium into the evaporator according to step a) can take place at an operating pressure which is regulated as a function of a temperature measured in the region of the electronic component. In other words, a variable pressure pump is used. The pressure to which the working medium is compressed with this pump before being introduced into the evaporator is then set as a function of a temperature value of the component to be cooled. This temperature value can be measured and provided by a sensor in the region of the component. This embodiment is particularly advantageous in order to enable a predetermined operating temperature (or a predetermined temperature range) for the electronic component to be maintained. The flow rate can be influenced by the pressure of the working medium flowing into the evaporator, and the flow rate in the evaporator in turn depends on the power consumption. The temperature of the electronic component can in turn be influenced via the heat power absorbed by the working medium. This allows a targeted regulation of the temperature of this component to be achieved.In a generally advantageous manner, the delivery of liquid working medium in step a) can be effected at an operating pressure in the range from 1 bar to 15 bar, preferably between 1 bar and 12 bar. An operating pressure in the stated range is particularly advantageous in order to allow the electronic component to be temperature-controlled within a typical predefined temperature window by evaporation of the working media described further above. The operating temperature of the component to be maintained can be below 95° C. for example and in particular in a range between 30° C. and 80° C.The invention will now be described by way of preferred embodiments with reference to the accompanying drawings, in which: FIG. 1 shows a schematic illustration of a cooling device, and FIG. 2 shows an embodiment of an evaporator in such a cooling device.In the figures, identical or functionally identical elements are provided with identical reference symbols.In FIG. 1, a schematic representation of a cooling device 1 according to a first example of the invention is shown. The cooling device 1 serves for cooling an electronic component 3 and in particular also a plurality of such components. For the sake of clarity, only one such component is shown here. The electronic component 3 can be, for example, a processor in a data center. The cooling device shown is designed to carry out the method according to the invention. For this purpose, it comprises a plant 10 for an organic rankine cycle process.The plant 10 is filled with an organic working medium M in the ready-to-use state. It is designed to circulate this working medium M in a closed circuit between a pump 11, an evaporator 12, an expansion turbine 13 and a condenser 14, which are each fluidically connected to one another via medium lines 40. Each of the elements shown therefore has a media inlet and a media outlet. In this case, the organic working medium M overall switches cyclically between a liquid and a gaseous aggregate state. The organic working medium M can be, for example, 1,3,3,3-tetrafluoroprop-1-ene, 1,1,1,3,3-pentafluoropropane, methoxyheptafluoropropane, methoxynonafluorobutane, ethoxynonafluorobutane, or dodecafluoro-2-methylpentan-3-one.The pump 11 serves for conveying liquid working medium M into the evaporator 12 according to step a) of the method. In this case, the liquid working medium M is present at an elevated operating pressure which is, for example, between 1.2 bar and 12 bar. At this operating pressure, the liquid working medium M is introduced into the evaporator 12. Here, the working medium M is evaporated from the electronic component 3 while absorbing heat, according to step b) of the method. In order to achieve this, the evaporator 12 has a cooling body 20 or consists essentially of such a cooling body 20. Both the component 3 and the cooling body 20 can each be configured in a planar manner, that is to say in other words have the shape of a plate. The contact surface between the component 3 and the heat sink 20 can therefore be comparatively large and correspond to a main surface of the heat sink or a partial region of one of its main surfaces. FIG. 1 accordingly shows a longitudinal section through a stack of these two plate-shaped objects 3 and 20. In reality, however, a plurality of such internal channels 21 acan also be present, which can run parallel or at an angle to one another, can branch off from one another and / or converge and can generally have a complex geometry. It is essential that the working medium can flow through the channel structure and in the process evaporate in the interior of the respective channels while absorbing waste heat of the electronic component 3. On the outlet side of the evaporator 12, therefore, substantially gaseous organic working medium M is present, wherein the temperature is increased in comparison with the inlet side.The gaseous working medium M is conducted from the evaporator 12 to the expansion turbine 13 and expanded therein to convert heat into mechanical energy. With the aid of this mechanical energy, a shaft 30 of the expansion turbine 13 is driven, which is coupled in a torque-transmitting manner to a generator G. With this generator G, mechanical energy is converted into electrical energy. This electrical energy can be used to supply the electronic components 3 proportionally with electrical energy. Thus, overall, the waste heat can be utilized in a meaningful manner locally within the data center.As it proceeds through the closed circuit, the organic working medium passes through the condenser 14, in which it is liquefied according to step d) of the method. This takes place while delivering heat to a cooling medium K (fluidic) located outside the closed circuit. This external cooling medium can be, for example, ambient air or cooling water (in the sense of open cooling) or else an additional cold accumulator, with which time-of-day fluctuations in the temperature of the ambient air or of the cooling water can be buffered. After the passage through the condenser 14, the working medium M is returned via the pump 11 into the evaporator 12, so that overall a closed medium circuit is formed.Purely optionally, a regenerator 17 is arranged fluidically between the expansion turbine 13 and the condenser 14. The liquefied working medium can additionally flow through this regenerator 17 between the pump 11 and the evaporator 12, so that overall thermal energy is transferred from the gaseous, warmer working medium M exiting from the expansion turbine 13 to the liquid, cooler working medium M exiting from the pump 11. The regenerator is therefore designed as a heat exchanger and serves to preheat the liquid working medium M on its way into the evaporator 12. This optional regenerator can thus contribute to a further increase in the energy efficiency.When a certain proportion of the working medium M passes through the plant 10, steps a), b), c) and d) are thus passed through cyclically one after the other. Since a partial amount of the working medium M is present in each part of the plant 10 at a given point in time, these steps, however, run simultaneously overall.FIG. 2 shows a detailed view of an evaporator 12 according to an exemplary embodiment of the invention. The evaporator 12 essentially consists of a metallic heat sink 20 which is connected to the rest of the media circuit via a media inlet 23 and a media outlet 24, as described above. The arrows here, as in FIG. 1, indicate the flow direction of the organic working medium M.In the example of FIG. 2, the heat sink is formed overall from a metallic material and manufactured using an additive manufacturing method. It has a fluid-tight outer wall 22 in order to encapsulate the regions through which working medium M flows against the external environment. This fluid-tight outer wall 22 surrounds an inner channel structure 21, which in this example is designed as an open-pored metallic foam 21 b. In this open-pore structure, the liquid working medium can be transported into the vicinity of the component 3 to be cooled and evaporate by absorbing waste heat within the channels. Subsequently, the working medium M in gas form is transported further through the channels of the foam 21 bto the medium outlet 24.In general and independently of the specific embodiment of the channel structure, it is favorable if the thermal connection of the working medium to the structural element 3 to be cooled is as tight as possible. In particular, there should be a smallest possible distance locally between the working medium M within the channel structure 21 and a semiconductor chip 50 of the component 3. FIG. 2 shows an electrical component 3 which comprises a semiconductor chip 50 within a chip housing 51. In this example, the thermal coupling of the semiconductor chip 50 to the working medium is provided by the wall of the chip housing 51 and the fluid-tight outer wall 22 of the cooling body. The distance between the working medium M and the semiconductor chip 50 is thus essentially given by the sum of the wall thickness of the chip housing 51 and the wall thickness of the outer wall 22. This distance should preferably be below 1 mm in order to enable a tight thermal coupling. When using a thin chip housing 51 and an additively manufactured cooling body 20 with an internal channel structure 21 and a thin outer wall 22, such a small distance can be achieved without difficulty.List of reference characters1 Cooling device 3 Component 10 Installation 11 Pump 12 Evaporator 13 Expansion turbine 14 Condenser 17 Regenerator 20 Cooling body 21 Duct structure 21 a Duct 21 b Open-pored foam 22 Outer wall 23 Medium inlet 24 Medium outlet 30 Shaft 40 Medium line 50 Semiconductor chip 51 Chip housing G Generator K External cooling medium M Working mediumReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedEP 3736519 A1

[0025] Cited Non-Patent Literaturehttps: / / www.lbeg.landeska.de / download / 52210)

[0028]

Claims

Cooling device (1) for cooling at least one electronic component (3), - wherein the cooling device (1) comprises a plant (10) for an organic Rankine cycle process, - wherein this plant (10) comprises a pump (11), an evaporator (12), an expansion turbine (13) and a condenser (14) and is designed for operation with an organic working medium (M) in a closed circuit, - wherein the evaporator (12) has a cooling body (20) made of a highly heat-conducting material, which is thermally coupled to the component (3) to be cooled and has a duct structure (21) for conducting the working medium (M) through at least in partial regions, - wherein the expansion turbine (13) comprises a shaft (30), which is coupled in a torque-transmitting manner to a generator (G) for generating electrical energy.Cooling device (1) according to claim 1, which is designed for cooling a plurality of processors (3) in a data center.Cooling device (1) according to one of claims 1 or 2, wherein the plant (10) is filled in an operational state with an organic working medium (M) comprising a media component selected from the following list of compound classes: - a hydrofluoroolefin, - an aliphatic saturated fluorocarbon, - a hydrofluoroether or perfluoroether, - a fluorinated ketone, in particular a perfluorinated ketone.Cooling device (1) according to claim 3, wherein the organic working medium (M) is or comprises a compound from the following list: - 1,3,3,3-tetrafluoroprop-1-ene, - 1,1,1,3,3-pentafluoropropane, - methoxyheptafluoropropane, - methoxynonafluorobutane, - ethoxynonafluorobutane, - dodecafluoro-2-methylpentan-3-one.Cooling device (1) according to either of Claims 3 and 4, in which the organic working medium (M) is characterized by at least one of the following properties: - a boiling temperature at normal pressure in the range between -20°C and 80°C, - a greenhouse potential below 1200, based on a time horizon of 100 years, - a specific electrical resistance above 10 8 Ohm·cm, - an electrical breakdown strength above 10 kV / mm, - an enthalpy of vaporization greater than 50 kJ / kg, - a vapor pressure at 80°C in the range between 100 kPa and 1200 kPa, - a specific heat capacity in the range between 950 J / (K·kg) and 1500 J / (K·kg).Cooling device (1) according to one of the preceding claims, in which the working medium (M) in a partial region of the evaporator (12) has a distance (d) of at most 3 mm from a semiconductor chip of the electronic component (3) to be cooled.Cooling device (1) according to one of the preceding claims, in which the cooling body (20) of the evaporator (12) is formed from a metallic material, wherein the channel structure (21) of the cooling body (20) is produced by an additive manufacturing method.Cooling device (1) according to one of the preceding claims, in which the condenser (14) is thermally coupled to an external cooling medium (K) located outside the closed circuit, such that the organic working medium (M) can be liquefied in the condenser (14) with the emission of heat to this external cooling medium (K).Cooling device (1) according to one of the preceding claims, which additionally has a regenerator (17) which is designed to transfer thermal energy from the working medium (M) emerging from the expansion turbine (13) to the working medium (M) emerging from the pump (11).Cooling device (1) according to one of the preceding claims, wherein the plant (10) is designed as a plant (10) for a multistage organic rankine cycle process.Cooling device (1) according to one of the preceding claims, which is designed for heating and / or cooling at least one further element or medium using the same working medium (M), in particular an element or medium from the following list: - an internal air of a data center, - a heating or cooling fluid for an interior of a building, - a transformer, an electrical line or another electrical component of an energy distribution system.Method for cooling at least one electronic component (3) using an organic Rankine cycle process, wherein a cooling device (1) according to one of the preceding claims is used and wherein the method comprises the following steps: a) conveying liquid working medium (M) into the evaporator (12) by means of the pump (11), b) evaporating the working medium (M) in the evaporator (12) while absorbing heat from the electronic component (3), c) expanding the working medium (M) in the expansion turbine (13) while converting heat into mechanical energy and while generating electrical energy by the generator (G) coupled to the expansion turbine (13) in a torque-transmitting manner, d) liquefying the working medium (M) in the condenser (14) with the release of heat to a cooling medium (K) located outside the closed circuit and returning the liquid working medium (M) to the evaporator (12).Method according to claim 12, wherein the electrical energy generated by the generator (G) is at least partially used for the operation of the at least one electronic component (3).Method according to Claim 12 or 13, in which the delivery of liquid working medium (M) takes place at an operating pressure in the range between 1 bar and 15 bar.Method according to one of Claims 12 to 14, in which the delivery of liquid working medium (M) takes place at an operating pressure which is regulated as a function of a temperature measured in the region of the electronic component (3).

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