Heat sink with pressure loss-optimized arrangement of cooling pins within the cooling channel
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- TRUMPF PATENTABTEILUNG
- Filing Date
- 2024-08-29
- Publication Date
- 2026-07-08
Smart Images
Figure EP2024074228_06032025_PF_FP_ABST
Abstract
Description
[0001] Heat sink with pressure loss-optimized arrangement of cooling pins within the cooling channel
[0002] Description
[0003] The invention relates to a heat sink for cooling a unit to be cooled, in particular an electrical unit, preferably a semiconductor device. Furthermore, the invention relates to a method for designing a heat sink for cooling a unit to be cooled, as well as a method for manufacturing a heat sink for cooling a unit to be cooled. The invention also relates to an electrical power converter for an industrial process device, preferably a plasma process device or heating device.
[0004] The invention lies in the field of electrical power conversion for special power-intensive industrial processes that are prone to instability, such as plasma excitation, plasma coating processes, gas laser excitation, particle accelerators, charging and discharging devices for large batteries, such as flow batteries, melting of solids, heating and / or gasification of liquid substances by, for example, microwave energy or induction heating. All of these processes have in common that they are designed to generate and accelerate charged atomic particles in a gas and / or plasma environment or liquid. All of these processes also have in common that they have a high power consumption, which is in the range of 1 kW or more, in particular 10 kW or more, preferably 100 kW or more. Many of these processes also have very high requirements for the stability of the power supply because the processes are highly complex, such as, for example,Semiconductor production using plasma processes and / or heating by electromagnetic fields. Typically, this involves converting power from a mains frequency in the range of approximately 50 Hz to 60 Hz to different frequencies, which can be in the range of 1 kHz to 200 MHz. Conversion to direct current power, also known as DC power, is also conceivable. This conversion of electrical power into other frequencies requires a large number of electronic components and assemblies, in particular power semiconductor components such as transistors or diodes designed for currents > 10 A and voltages > 400 V. These electronic components and assemblies generate heat loss during operation. This heat loss is often generated in a very limited area of just a few mm. 2It is a particular challenge to dissipate this waste heat in order to protect the components and / or assemblies from being destroyed by overheating. Very large and material-intensive heat sinks are often provided for this purpose, the production of which is very expensive. In the prior art, this amount of heat is dissipated by cooling using a cold plate. When cooling with such a conventional cold plate, the heat transfer from the electrical component, which may have a copper layer, to the cooling medium is achieved by applying a material such as thermal paste in the thermal interface, which dissipates the generated heat. However, this type of thermal interface material proves to be disadvantageous. On the one hand, it represents a further heat transfer with thermal resistance, and on the other hand, it is subject to wear, which gradually deteriorates its effectiveness during operation.The surface area of the cooling plate is also increased, or the number and performance of the components is reduced in order to dissipate a greater amount of heat or generate a smaller amount of heat. Both options prove insufficient. Since the space in the housing of such a power supply is limited, expanding the cooling surface is not possible indefinitely. Reducing the performance of individual components is also not effective. Overall, inadequate cooling of the electrical components results in costs.
[0005] Heat sinks are designed to dissipate the heat generated during operation of a unit to be cooled. For this purpose, heat sinks have a cooling channel through which coolant, in particular coolant liquid, preferably cooling water, can flow. To achieve high cooling performance, it is advantageous to design the interior of the cooling channel so that close thermal contact is established between the heat sink and the coolant. At the same time, however, the interior of the cooling channel should be designed so that the pressure loss of the coolant flowing through the cooling channel is not excessive.
[0006] It is therefore an object of the invention to provide a heat sink which enables good heat transfer from the heat sink to the coolant with low pressure loss of the coolant flowing through the cooling channel.
[0007] The stated problem is solved by a heat sink for cooling a unit to be cooled, in particular an electrical unit, preferably a semiconductor device. This unit to be cooled, in particular an electrical unit, preferably a semiconductor device, can in particular be part of an electrical power converter for converting electrical power from the power grid into an electrical power > 1 kW for supplying an industrial process, in particular a plasma processing process, a laser excitation process, or a heating process using electromagnetic power.
[0008] The semiconductor arrangement can in particular comprise a power semiconductor component, wherein the power converter is designed such that the power semiconductor component can be operated at a frequency greater than 20 kHz in switching or amplifier mode and can generate an electrical power loss of > 500 W. The heat sink has a cooling channel through which coolant, in particular cooling liquid, preferably cooling water, can flow in a predetermined flow direction, wherein the cooling channel has a first cooling wall on the side of the cooling channel facing the unit to be cooled. A plurality of cooling pins are arranged in the cooling channel or in a partial region of the cooling channel and extend from the first cooling wall into the cooling channel.The plurality of cooling pins comprises at least one cooling pin of a first category, which is oriented in a first inclination direction that is inclined relative to a perpendicular to the first cooling wall. The cooling pins of the plurality of cooling pins are arranged such that a cooling pin of the plurality of cooling pins does not intersect any other cooling pin of the plurality of cooling pins. In the heat sink, a plurality of cooling pins are arranged in the cooling channel or in a partial region of the cooling channel, which cooling pins extend from the first cooling wall into the cooling channel. A cooling pin is understood to be a cooling element whose length is greater than the average width or the average diameter of the cooling element. In particular, a cooling pin can be formed, for example, with a cylindrical or tapered geometry. The directional extension of the cooling pin can preferably be represented by a center line of the cooling pin.According to an exemplary embodiment, to determine such a centerline, a line could be drawn through the centers of the cross sections along the cooling pin. The centerline of a cooling pin can be formed as a straight line, for example, but it can also be slightly curved or slightly bent, for example.
[0009] In one aspect, at least the cooling pins of the first category are oriented at an angle relative to a perpendicular to the first cooling wall. "Angle-angled" here means that the cooling pins of the first category are neither parallel nor perpendicular to the first cooling wall. It has been found that the angled arrangement of the cooling pins allows for particularly good coolant flow and improved thermal contact between the cooling pin and the coolant.
[0010] In one aspect, the cooling pins of the plurality of cooling pins are arranged such that no cooling pin intersects any other cooling pin of the plurality of cooling pins. This non-overlapping arrangement of the cooling pins in the cooling channel or in a partial region of the cooling channel achieves improved flow through the cooling channel and a reduction in pressure loss. The pressure required to convey the coolant through the cooling channel has proven to be particularly low in the solution according to the invention. In one aspect, an electrical power converter is disclosed for an industrial process arrangement, preferably a plasma process arrangement or heating arrangement, comprising:
[0011] - a heat sink as described above and below,
[0012] - a circuit board,
[0013] - a unit to be cooled, in particular an electrical unit, preferably a semiconductor device, preferably comprising a power semiconductor component,
[0014] - further electronic components, wherein the further electronic components and the unit to be cooled are arranged on or at a printed circuit board and are connected by electrical contacts, wherein the unit to be cooled has a fixed, in particular material-locking, connection with the heat sink.
[0015] A preferred result of the development is to create a connection between the unit to be cooled and the heat sink with as little additional material and as thin as possible. During the considerations, simulations and tests for this development it became clear that this is particularly possible if the heat sink through which fluid flows is firmly connected, in particular by a material bond, to the unit to be cooled. This can be achieved, for example, by soldering, sintering, pressing or direct copper bonding (DCB). By "firm" here we mean "can only be removed by destruction". In other words, by means of a connection that cannot be removed even with tools without destroying either the unit to be cooled or the heat sink or both components.
[0016] In one aspect, a method is disclosed for designing a heat sink for cooling a unit to be cooled. The heat sink has a cooling channel through which coolant can flow in a predetermined flow direction, wherein the cooling channel has a first cooling wall on the side of the cooling channel facing the unit to be cooled. The method comprises arranging a plurality of cooling pins in the cooling channel, which extend from the first cooling wall into the cooling channel. The plurality of cooling pins comprises at least one cooling pin of a first category, which is oriented in a first inclination direction that is inclined obliquely relative to a perpendicular to the first cooling wall. The cooling pins of the plurality of cooling pins are arranged such that one cooling pin of the plurality of cooling pins does not intersect any other cooling pin of the plurality of cooling pins.
[0017] In one aspect, a further method is disclosed for producing a heat sink for cooling a unit to be cooled. The heat sink has a cooling channel through which coolant can flow in a predetermined flow direction, wherein the cooling channel has a first cooling wall on the side of the cooling channel facing the unit to be cooled. The method comprises producing a plurality of cooling pins within the cooling channel, which extend from the first cooling wall into the cooling channel, by means of an additive process. The plurality of cooling pins comprises at least one cooling pin of a first category, which is oriented in a first inclination direction that is inclined obliquely relative to a perpendicular to the first cooling wall. The cooling pins of the plurality of cooling pins are arranged such that one cooling pin of the plurality of cooling pins does not intersect any other cooling pin of the plurality of cooling pins.
[0018] Advantageous training and further developments, which can be used individually or in combination with one another, are the subject of the dependent claims and the following description.
[0019] In one aspect, each cooling pin of the plurality of cooling pins is arranged such that coolant can flow around it all around. This enables high heat transfer from the cooling pins to the coolant.
[0020] It is advantageous if the cooling pins of the plurality of cooling pins are arranged such that no cooling pin of the plurality of cooling pins touches any other cooling pin of the plurality of cooling pins. This creates a gap between the cooling pins. This facilitates flow through the cooling channel and reduces pressure loss.
[0021] In one aspect, the first inclination direction, viewed in a first projection direction, is inclined obliquely to the perpendicular to the first cooling wall, wherein the first projection direction is the intended flow direction of the coolant, and the first inclination direction, viewed in a second projection direction, is also inclined obliquely to the perpendicular to the first cooling wall, wherein the second projection direction is orthogonal to both the intended flow direction and the perpendicular to the first cooling wall. This oblique orientation of the cooling pin, viewed both in the projection direction and in the second projection direction, results in an advantageous flow pattern in the cooling channel, which, on the one hand, reduces the flow resistance in the cooling channel and, on the other hand, enables efficient heat transfer from the cooling pins to the coolant.
[0022] In one aspect, when viewed in a first projection direction, the first inclination direction in a first projection plane is inclined obliquely to the perpendicular to the first cooling wall, wherein the first projection direction is the intended flow direction of the coolant and wherein the first projection plane is the plane perpendicular to the first projection direction, and when viewed in a second projection direction, the first inclination direction in a second projection plane is inclined obliquely to the perpendicular to the first cooling wall, wherein the second projection direction is orthogonal to both the intended flow direction and the perpendicular to the first cooling wall, and wherein the second projection plane is the plane perpendicular to the second projection direction. Both in the first projection plane and in the second projection plane, an obliquely inclined orientation of the cooling pin results.
[0023] In one aspect, the first inclination direction in the first projection plane, viewed in the first projection direction, is inclined by a first angle relative to the perpendicular to the first cooling wall. The first angle is preferably a positive or negative angle in the range between 0° and 90°, more preferably in the range between 10° and 80°, more preferably in the range between 20° and 70°, more preferably in the range between 30° and 60°, more preferably in the range between 35° and 55°, more preferably in the range between 40° and 50°.
[0024] In one aspect, the first angle is a positive or negative angle of approximately 45°. An orientation at an angle of approximately 45° has proven particularly advantageous for improving heat transfer from the cooling pin to the coolant and reducing the pressure drop of the coolant flowing through the cooling channel.
[0025] In one aspect, the first inclination direction in the second projection plane, viewed in the second projection direction, is inclined by a second angle relative to the perpendicular to the first cooling wall. The second angle is preferably a positive or negative angle in the range between 0° and 90°, more preferably in the range between 10° and 80°, more preferably in the range between 20° and 70°, more preferably in the range between 30° and 60°, more preferably in the range between 35° and 55°, more preferably in the range between 40° and 50°.
[0026] It is advantageous if the second angle is a positive or negative angle of approximately 45°. This improves heat transfer from the cooling pin to the coolant and reduces the pressure loss of the coolant flowing through the cooling channel.
[0027] In one aspect, the plurality of cooling pins comprises at least one cooling pin of a second category oriented in a second inclination direction that is inclined relative to the perpendicular to the first cooling wall, wherein the second inclination direction is different from the first inclination direction. In this embodiment, the plurality of pins comprises cooling pins of the first category oriented in a first inclination direction and cooling pins of the second category oriented in a second inclination direction. The different orientation of the cooling pins creates a flow pattern in the cooling channel that has proven advantageous for efficient heat dissipation.
[0028] In one aspect, the second inclination direction, viewed in a first projection direction, is inclined obliquely relative to the perpendicular to the first cooling wall, wherein the first projection direction is the intended flow direction of the coolant. Also viewed in a second projection direction, the second inclination direction is inclined obliquely relative to the perpendicular to the first cooling wall, wherein the second projection direction is orthogonal to both the intended flow direction and the perpendicular to the first cooling wall. The cooling pins of the second category are also oriented obliquely, both viewed in the first projection direction and viewed in the second projection direction.
[0029] In one aspect, the second inclination direction, viewed in the first projection direction, is inclined in a first projection plane by a third angle to the perpendicular to the first cooling wall, wherein the first projection plane is the plane perpendicular to the first projection direction. Preferably, the third angle is a positive or negative angle in the range between 0° and 90°, more preferably in the range between 10° and 80°, more preferably in the range between 20° and 70°, more preferably in the range between 30° and 60°, more preferably in the range between 35° and 55°, more preferably in the range between 40° and 50°.
[0030] In one aspect, the second inclination direction in the second projection plane, viewed in the second projection direction, is inclined by a fourth angle to the perpendicular to the first cooling wall, wherein the second projection plane is the plane perpendicular to the second projection direction. The fourth angle is preferably a positive or negative angle in the range between 0° and 90°, more preferably in the range between 10° and 80°, more preferably in the range between 20° and 70°, more preferably in the range between 30° and 60°, more preferably in the range between 35° and 55°, more preferably in the range between 40° and 50°.
[0031] In one aspect, a plurality of cooling pins of the first category are arranged along a first straight line running along the first cooling wall. In this embodiment, a plurality of cooling pins are arranged along a straight line with a consistent orientation. The resulting structure, consisting of a plurality of cooling pins spaced apart from one another and oriented in the same direction, enables effective heat transfer to the flowing coolant with low flow resistance.
[0032] In one aspect, when viewed in a third projection direction, the first inclination direction is inclined at a fifth angle to the perpendicular to the first cooling wall, the third projection direction being the direction of the first straight line, and when viewed in a fourth projection direction, the first inclination direction is inclined at a sixth angle to the perpendicular to the first cooling wall, the fourth projection direction being orthogonal to both the first straight line and the perpendicular to the first cooling wall.
[0033] In one aspect, the plurality of cooling pins comprises a plurality of cooling pins that are opposite to the cooling pins of the first category and oriented in an inclination direction opposite to the first inclination direction, wherein a plurality of the cooling pins that are opposite to the cooling pins of the first category are arranged along a second straight line that runs parallel to the first straight line along the first cooling wall. In this embodiment, a plurality of cooling pins that are opposite to the cooling pins of the first category are arranged along a second straight line. The opposing rows of cooling pins further improve heat transfer to the coolant.
[0034] In one aspect, viewed in the third projection direction, the inclination direction opposite to the first inclination direction is inclined by a seventh angle to the perpendicular to the first cooling wall, wherein the third projection direction is the direction of the first straight line, and viewed in the fourth projection direction, the inclination direction opposite to the first inclination direction is inclined by an eighth angle to the perpendicular to the first cooling wall, wherein the fourth projection direction is orthogonal to both the first straight line and the perpendicular to the first cooling wall, wherein the seventh angle corresponds to the fifth angle with a negative sign and the eighth angle corresponds to the sixth angle.
[0035] In one aspect, a plurality of identical unit cells are arranged in the cooling channel or in the partial region of the cooling channel, wherein a second plurality of cooling pins are arranged within each unit cell and are intended to extend from the first cooling wall into the cooling channel. The use of such a unit cell simplifies the design of a heat sink.
[0036] In one aspect, the cooling pins of the second plurality of cooling pins are arranged within the unit cell such that a cooling pin of the second plurality of cooling pins does not intersect any other cooling pin of the second plurality of cooling pins. Avoiding intersections between cooling pins ensures low flow resistance in the cooling channel.
[0037] In one aspect, a unit cell comprises at least one cooling pin of the first category oriented in the first inclination direction, which is inclined at an angle relative to the perpendicular to the first cooling wall, and at least one cooling pin of a second category oriented in a second inclination direction, which is inclined at an angle relative to the perpendicular to the first cooling wall, wherein the second inclination direction is different from the first inclination direction. The cooling pins of different orientations provided by the unit cell ensure effective heat dissipation.
[0038] It is advantageous if the cooling channel or a portion of the cooling channel is filled with a plurality of adjacently arranged unit cells. The repeated arrangement of unit cells in the cooling channel simplifies and accelerates the design and manufacture of the heat sink.
[0039] In one aspect, the plurality of unit cells arranged in multiple rows and / or multiple columns fill the cooling channel or a portion of the cooling channel.
[0040] In one aspect, the height of the unit cell corresponds to the height of the cooling channel. This adapts the geometry of the unit cell to the geometry of the cooling channel. The cooling channel can be filled by adjacent unit cells.
[0041] In one aspect, the unit cell is cuboid-shaped. The cuboid shape of the unit cell simplifies filling the cooling channel with adjacent unit cells.
[0042] It is advantageous to use the unit cell as the basic design unit for the heat sink design. Once the unit cell is designed, the heat sink can be manufactured.
[0043] In one aspect, the cooling pins are rod-shaped. Further preferably, the cooling pins have a substantially cylindrical shape. The rod-shaped or cylindrical design of the cooling pins creates a large contact surface for heat transfer from the cooling pins to the coolant.
[0044] In one aspect, the cooling pins have a round or oval cross-section. This can further reduce flow resistance.
[0045] It is advantageous if the cooling channel has a second cooling wall on the side of the cooling channel opposite the first cooling wall. In one aspect, the cooling pins of the plurality of cooling pins extend continuously from the first cooling wall to the second cooling wall. In this way, heat can be supplied to the cooling pins from both the first cooling wall and the second cooling wall. This achieves improved heat dissipation.
[0046] In one aspect, the first cooling wall is arranged substantially parallel to the second cooling wall. The parallel alignment of the first cooling wall and the second cooling wall ensures a homogeneous flow through the cooling channel with turbulent flow conditions inside.
[0047] It is advantageous if the cooling channel has a substantially constant cross-section across the entire heat sink. This results in a constant coolant flow velocity throughout the cooling channel. This is advantageous with a local dependence of the flow velocity, which leads to a desired turbulent system.
[0048] In one aspect, the cooling channel has a substantially rectangular cross-section. Furthermore, it is advantageous if the cooling channel is configured as a substantially cuboid-shaped cooling channel. Such geometries simplify the formation of flat contact surfaces for thermally connecting the units to be cooled.
[0049] It is advantageous if the heat sink is a micro heat sink and the unit to be cooled is an electronic component. According to this embodiment, a separate micro heat sink can be provided for each electronic component. This enables heat dissipation that is individually tailored to the respective electronic component. The unit to be cooled is preferably an electronic assembly.
[0050] In one aspect, the heat sink has an inlet, wherein coolant can be supplied via the inlet at a first end of the cooling channel. Further preferably, the heat sink has an outlet, wherein coolant can be discharged via the outlet at a second end of the cooling channel, wherein the second end of the cooling channel is arranged opposite the first end of the cooling channel. This allows coolant to flow through the entire heat sink.
[0051] In one aspect, the heat sink is made of metal. Metals generally have high thermal conductivity. According to a preferred embodiment, the heat sink is made of copper. Copper is a metal with very high thermal conductivity and is therefore preferably used for the construction of heat sinks. According to an alternative preferred embodiment, the heat sink is made of one of molybdenum, stainless steel, and nickel.
[0052] In one aspect, the cooling pins of the heat sink are manufactured using an additive manufacturing process, in particular selective laser melting (SLM). Using such additive manufacturing processes, the cooling pins can be applied to the first cooling wall of the heat sink in virtually any orientation. Even with additive manufacturing, certain restrictions must be observed in the structure, for example, on the inside, such as:
[0053] Installation angle, which should in particular be less than 45°, which would otherwise not be possible without a support structure.
[0054] In one aspect, the plurality of cooling pins is arranged such that a cooling pin of the first category overlaps with a cooling pin of the second category at a viewing angle parallel to the cooling wall, in particular at a viewing angle of the coolant flow direction. "Overlapping" here means that at least one cooling pin of the first category at least partially obscures another cooling pin of the second category in the predetermined viewing direction. Such an arrangement can improve the turbulence of the coolant at the cooling pins and, consequently, the heat transfer from the cooling pins to the coolant.
[0055] In one aspect, the plurality of cooling pins is arranged such that a cooling pin of the first category is intertwined with two cooling pins of the second category at a viewing angle parallel to the cooling wall, in particular at a viewing angle of the coolant flow direction. "Intertwined" here means that at least one first cooling pin of the first category at least partially obscures a second cooling pin of the second category in the given viewing direction, and the first cooling pin itself is also at least partially obscured by another cooling pin of the second category in the given viewing direction. Such an arrangement can further improve the turbulence of the coolant at the cooling pins and, consequently, the heat transfer from the cooling pins to the coolant.
[0056] Further advantageous embodiments are described in more detail below with reference to several exemplary embodiments shown in the drawings, to which, however, the development is not limited. It shows schematically:
[0057] Fig. 1 a heat sink together with a unit to be cooled in longitudinal section.
[0058] Fig. 2 a distribution unit and a circuit board which has recesses for several units to be cooled.
[0059] Fig. 3 an industrial process arrangement, preferably a plasma process arrangement or heating arrangement with a heat sink.
[0060] Fig. 4 shows a cooling channel of a heat sink in which a plurality of cooling pins are arranged.
[0061] Fig. 4A is an oblique view of a cooling pin of a first category.
[0062] Fig. 4B shows a representation of the cooling pin of the first category in a first projection plane.
[0063] Fig. 4C shows a representation of the cooling pin of the first category in a second projection plane. Fig. 5A shows a representation of a cooling pin of a second category in an oblique view.
[0064] Fig. 5B shows a representation of the cooling pin of the second category in a first projection plane.
[0065] Fig. 5C shows a representation of the cooling pin of the second category in a second projection plane.
[0066] Fig. 6 shows an oblique view of a cooling pin of a third category.
[0067] Fig. 7 shows an oblique view of a cooling pin of a fourth category.
[0068] Fig. 8 shows a preferred embodiment in which cooling pins of a first category are arranged along a first straight line and opposite cooling pins are arranged along a second straight line.
[0069] Fig. 9A shows a unit cell within which a second plurality of cooling pins is arranged.
[0070] Fig. 9B shows a cooling channel, wherein in a partial region of the cooling channel several identical unit cells are arranged adjacent to one another.
[0071] In the following description of preferred embodiments of the present invention, like reference numerals designate like or comparable components.
[0072] Fig. 1 shows a heat sink 5 according to the embodiments of the present invention together with a unit 10 to be cooled in longitudinal section. The unit 10 to be cooled is preferably a semiconductor assembly, and particularly preferably comprises a transistor. The heat sink 5 is attached to a distribution unit 20 by means of fastening means 15, preferably screws. For this purpose, receiving devices for fastening means 16 are provided in this. A first flow channel 25 and a second flow channel 30 for the coolant can be seen within the distribution unit 20. The heat sink 5 has a cooling channel 35. Coolant is supplied to the cooling channel 35 of the heat sink 5 via the first flow channel 25 and a coolant supply 40. A coolant discharge 45 is provided at the end of the cooling channel 35 opposite the coolant supply 40.The coolant can be discharged via the coolant discharge 45 and the second flow channel 30 after flowing through the cooling channel 40.
[0073] The heat sink 5 has a first cooling wall 50 on the side facing the unit 10 to be cooled. On the side of the heat sink 5 facing away from the unit 10 to be cooled, the cooling channel 40 is defined by a second cooling wall 55, which is opposite the first cooling wall 50. Preferably, the second cooling wall 55 is formed parallel to the first cooling wall 50. The heat sink 5 is at least partially in thermal contact with the distribution unit 20 via the second cooling wall 55.
[0074] The unit 10 to be cooled can, for example, be soldered to the heat sink 5 or, alternatively, be thermally connected to the heat sink 5, for example, via a thermal paste. The unit 10 to be cooled comprises an array of transistors 60. The heat generated during operation of the transistors 60 is dissipated via the heat sink 5, which in turn is cooled by the coolant flowing in the cooling channel 35.
[0075] A plurality of cooling pins 65 are arranged inside the cooling channel 35, extending from the first cooling wall 50 into the cooling channel 35. Coolant flows around the cooling pins 65 and ensures improved thermal connection between the heat sink 5 and the coolant flowing through the cooling channel 35.
[0076] The heat sink 5 is preferably made of copper. Alternatively, the heat sink could be made of stainless steel, nickel, or molybdenum, for example. The distribution unit 20, onto which the heat sink 5 is screwed, is preferably made of copper. This can be embedded in a support unit 21, which is preferably made of aluminum.
[0077] The heat sink 5 is detachably connected to a cooling unit 22. In the example shown in the figures, the cooling unit 22 comprises a distribution unit 20 designed to supply the heat sink 5 with coolant. The cooling unit 22 also comprises a support unit 21 into which the distribution unit 20 is inserted. The cooling unit 22 has a receptacle 23 into which the heat sink 5 can be detachably inserted. The heat sink 5 is then fastened to the cooling unit 22 by means of at least one fastening means 15, preferably by means of one or more screws. The cooling unit 22 has at least one receiving device 16 for the at least one fastening means 15. In order to separate the heat sink 5 from the cooling unit 22 again, the at least one fastening means 15 is first released.The heat sink 5 can then be removed from the holder 23 of the cooling unit 22 together with the unit 10 to be cooled mounted thereon.
[0078] The cooling unit 22 comprises a first fluid port 41, which is fluidically connected to the first flow channel 25, and a second fluid port 46, which is fluidically connected to the second flow channel 30.
[0079] A 'fluidic connection' is a connection designed to allow a fluid to flow through it.
[0080] A 'fluid port' is an opening designed to allow a fluid to pass through it, and to allow a component having such an opening to be connected to it so that this fluid can pass through these openings.
[0081] When inserting and subsequently fastening the heat sink 5 in the
[0082] In the receptacle 23, a first fluidic connection is formed between the first fluid port 41 and a coolant supply 40 and a second fluidic connection is formed between the second fluid port 46 and the coolant discharge 45.
[0083] To seal the first fluidic connection, a first sealing ring 42 is arranged in a groove 43 between the cooling unit 22 and the heat sink 5, wherein the sealing ring 42 completely surrounds the first fluid port 41. Likewise, a second sealing ring 44 is provided on the second fluid port 46, which completely surrounds the second fluid port 46 and is arranged in a groove 43 between the cooling unit 22 and the heat sink 5. When the at least one fastening means 15 is attached, for example when tightening the at least one screw, the heat sink 5 is pressed against the first fluid port 41 and the first sealing ring 42 as well as against the second fluid port 46 and the second sealing ring 44. As a result of this pressing, a liquid-tight first fluidic connection and a liquid-tight second fluidic connection are formed between the cooling unit 22 and the heat sink 5.
[0084] As shown in Fig. 1, a cooling flow 36 can be formed within the cooling device. The coolant flows from the first flow channel 25 via the first fluid port 41 and the coolant supply 40 into the cooling channel 35. The coolant flows through the cooling channel 35 and is discharged via the coolant outlet.
[0085] Fig. 1 shows the overlap and, in particular, the interweaving of the cooling pins of different categories in a viewing direction parallel to the first cooling wall 50. A more detailed description of the overlap and interweaving can also be found further below in the description of Fig. 4.
[0086] In Fig. 1, it can also be seen that the unit 10 to be cooled, together with the heat sink 5 arranged underneath it, is arranged within a first recess 70 of a printed circuit board 75. In Fig. 2, the arrangement of the unit 10 to be cooled within the first recess 70 of the printed circuit board 75 is clearly visible. Fig. 2 shows the distribution unit 20 and the printed circuit board 75 attached to the distribution unit 20. The unit 10 to be cooled, with the heat sink 5 arranged underneath it, is arranged within the first recess 70 of the printed circuit board 75, which is shown in longitudinal section in Fig. 2.
[0087] Within the unit 10 to be cooled, the arrangement of transistors 60 can be seen, the waste heat from which is dissipated by the heat sink 5. The heat sink 5 is screwed to the distribution unit 20 by means of the fastening means 15, preferably by means of the screw. The cooling channel 35 of the heat sink 5 is delimited by the first cooling wall 50 and the second cooling wall 55. Coolant is supplied to the cooling channel 35 via the first flow channel 25 and the coolant supply 40. The coolant flows through the cooling channel 35 and flows around the plurality of cooling pins 65. After flowing through the cooling channel 35, the coolant is discharged via the coolant discharge 45 and the second flow channel 30.
[0088] In addition to the unit 10 to be cooled, Fig. 2 also shows a further unit 80 to be cooled together with a further heat sink 85 arranged underneath it. The further unit 80 to be cooled is arranged within a further recess 90 provided in the circuit board 75, and the associated further heat sink 85 is inserted into a further receptacle 92 of the cooling unit 22. The further heat sink 85 has a further cooling channel 95, which is connected to the second flow channel 30 via a further coolant discharge 100. Electrical connection terminals 105 can be seen on the further unit 80 to be cooled, which are provided for forming electrical connections between the further unit 80 to be cooled and the circuit board 75.
[0089] The cooling unit 22 shown in Fig. 2 is designed to supply coolant to a plurality of heat sinks and to discharge the coolant again after flowing through the heat sinks. In the example of Fig. 2, the cooling unit 22 is designed to supply coolant to both the heat sink 5 and the additional heat sink 85 and then discharge it again from both the heat sink 5 and the additional heat sink 85. In particular, the cooling unit 22 is designed to distribute the coolant evenly among the various heat sinks.
[0090] The additional heat sink 85 is also fluidically connected to the cooling unit 22 when fastened in the additional receptacle 92. The sectional view of Fig. 2 shows that the additional cooling channel 95 is connected via the additional coolant discharge 100 and the additional second fluid port 102 to the second flow channel 30, through which the coolant is discharged.
[0091] The printed circuit board 75 shown in Fig. 2, together with the units 10 and 80 to be cooled and the heat sinks 5 and 85 fastened to the printed circuit board 75, forms a structural unit which, in its entirety, can be placed on the cooling unit 22 and also removed again, i.e., which can be detachably connected to the cooling unit 22. When this structural unit is placed on the cooling unit 22, the heat sinks 5, 85 attached to the units 10, 80 to be cooled are inserted into the corresponding receptacles 23, 92 of the cooling unit 22. The heat sinks 5, 85 are then fastened to the cooling unit 22 by means of the at least one fastening means 15, wherein, when the heat sinks 5, 85 are fastened to the cooling unit 22, fluidic connections for supplying and discharging coolant are formed between the respective heat sinks 5, 85 and the cooling unit 22.The cooling unit 22 is designed to uniformly supply all heat sinks 5, 85 of the structural unit with coolant and to discharge the coolant again after flowing through the heat sinks 5, 85. Fig. 3 shows an industrial process arrangement 1, preferably a plasma process arrangement or heating arrangement.
[0092] The industrial process arrangement 1 has:
[0093] - an electrical power converter 4,
[0094] - a load 2, preferably a plasma process or heating process, e.g. an induction or microwave heating process, wherein the load 2 is electrically connected to the electrical power converter 4 so that the electrical power converter 4 can supply the load 2 with the required electrical power,
[0095] - optionally an additional adaptation unit 3, which is connected between the power converter 4 and the load 2.
[0096] The power converter 4 has:
[0097] - a heat sink 5 as described above and below,
[0098] - a cooling unit 22 comprising, as described above and below, one or more distribution units 20 and a carrier unit 21,
[0099] - a circuit board 75,
[0100] - a unit 10 to be cooled, in particular an electrical unit, preferably a semiconductor device, preferably comprising a power semiconductor component,
[0101] - further electronic components 8a, 8b, 8c, wherein the further electronic components 8a, 8b, 8c and the unit 10 to be cooled are arranged on or at a printed circuit board 75 and are connected by electrical contacts, wherein the unit 10 to be cooled has a fixed, in particular material-locking, connection with the heat sink 5.
[0102] Fig. 4 shows the cooling channel 35 of the heat sink 5 together with the plurality of cooling pins 65 arranged within the cooling channel 35. The cooling channel 35 is delimited by the first cooling wall 50 facing the first unit 10 to be cooled, the second cooling wall 55 arranged opposite the first cooling wall 50, and by the side walls 111, 116. The cooling channel 35 preferably has a substantially rectangular flow cross-section. More preferably, the cross-section of the cooling channel 35 is substantially constant over the entire length of the cooling channel 35. The coolant flow direction 121 within the cooling channel 35 is illustrated by an arrow in Fig. 4. As can be seen from the x, y, z coordinate system also shown in Fig. 4, the coolant flows through the cooling channel 35 in the z-direction. It can also be seen that the first cooling wall 50 is parallel to the zy plane.Accordingly, the direction 135 perpendicular to the first cooling wall 50 points in the x-direction.
[0103] The plurality of cooling pins 65 extend from the first cooling wall 50 into the interior of the cooling channel 40. According to the embodiment shown in Fig. 4, the cooling pins 65 extend into the cooling channel 35, but do not extend as far as the second cooling wall 55, so that a distance exists between the ends of the cooling pins 65 facing away from the first cooling wall 50 and the second cooling wall 55. According to an alternative preferred embodiment of the invention, which is not shown in Fig. 4, it can be provided that the plurality of cooling pins 65 extend continuously from the first cooling wall 50 to the second cooling wall 55. Each cooling pin of the plurality of cooling pins 65 is arranged within the cooling channel 35 such that it does not intersect any other cooling pin of the plurality of cooling pins 65. As a result, coolant can flow all around each of the cooling pins 65.
[0104] The plurality of cooling pins 65 comprises cooling pins 125 of a first category, which are aligned in a first inclination direction 130. The first inclination direction 130 is inclined obliquely relative to a direction 135 perpendicular to the first cooling wall 50. Furthermore, the plurality of cooling pins 65 comprises cooling pins 140 of a second category, which are aligned in a second inclination direction 145. The second inclination direction 145 is inclined obliquely relative to the direction 135 perpendicular to the first cooling wall 50, wherein the second inclination direction 145 differs from the first inclination direction 130. It can also be seen from Fig. 4 that the plurality of cooling pins 65 overlap at a viewing angle parallel to the cooling wall 50, in particular at a viewing angle of the coolant flow direction 121.By "overlap" is meant here that at least one cooling pin 125 of the first category at least partially covers another cooling pin 140 of the second category in the given viewing direction.
[0105] It is also evident from Fig. 4 that the plurality of cooling pins 65 intertwine at a viewing angle parallel to the cooling wall 50, in particular at a viewing angle of the coolant flow direction 121. "Intertwine" here means that at least a first cooling pin 125 of the first category at least partially obscures a second cooling pin 140 of the second category in the given viewing direction, and the first cooling pin itself is also at least partially obscured by another cooling pin 140 of the second category in the given viewing direction.
[0106] The cooling pins 65 arranged within the cooling channel are preferably manufactured by means of an additive manufacturing process, preferably by means of selective laser melting.
[0107] In Figs. 4A, 4B, 4C, projection representations are shown how the cooling pins 125 of the first category are aligned at an angle within the cooling channel 35.
[0108] Fig. 4A shows an oblique view of a cooling pin 125 of the first category. The cooling pin 125 is oriented in a first inclination direction 130 relative to a direction 135 perpendicular to the first cooling wall 50. Together with the cooling pin 125 of the first category, a coordinate system corresponding to the coordinate system of Fig. 4 is shown in Fig. 4A. First, the cooling pin 135 of the first category is viewed in a first projection direction 150. The first projection direction 150 corresponds to the flow direction of the coolant, i.e., the z-direction. If the cooling pin 125 of the first category is viewed in the first projection direction 150, the representation shown in Fig. 4B is obtained in a first projection plane perpendicular to the first projection direction 150. This first projection plane is the xy-plane.It can be seen that the cooling pin 125 of the first category is inclined at a first angle 155 relative to the vertical direction 135 in this first projection plane. The cooling pin 125 is inclined counterclockwise relative to the vertical direction 135, therefore the first angle 155 has a negative value in the range between 0° and -90°.
[0109] Next, the cooling pin 125 is viewed along a second projection direction 160, which is also shown in Fig. 4A. This second projection direction 160 is orthogonal to both the flow direction of the coolant and the direction 135 perpendicular to the first cooling wall 50. Viewing the cooling pin 125 in the second projection direction 160 results in the illustration shown in Fig. 4C in a second projection plane perpendicular to the second projection direction 160. This second projection plane is the xz plane. Fig. 4C shows that the cooling pin 125 of the first category is oriented in this second projection plane at an angle 165 to the perpendicular direction 135. The cooling pin 125 is inclined counterclockwise relative to the perpendicular direction 135; therefore, the second angle 165 has a negative value in the range between 0° and -90°.
[0110] From Figs. 4A to 4C, it can be seen that the cooling pins 125 of the first category are oriented at an angle to the vertical direction 135 in two respects. Both viewed in the first projection direction 150 and viewed in the second projection direction 160, the cooling pins 125 of the first category are oriented at an angle to the vertical direction 135.
[0111] 5A, 5B, 5O show, using projection representations, the manner in which the cooling pins 140 of the second category are aligned at an angle within the cooling channel 35. In Fig. 5A, the orientation of a cooling pin 140 of the second category is shown in an oblique view together with a coordinate system that corresponds to the coordinate system shown in Fig. 4. The z-direction again indicates the flow direction of the coolant. The cooling pin 140 is aligned in a second inclination direction 145 relative to a direction 135 perpendicular to the first cooling wall 50. If the cooling pin 140 of the second category is viewed in the first projection direction 150, which corresponds to the flow direction of the coolant, the representation shown in Fig. 5B is obtained in a first projection plane perpendicular to the first projection direction 150. This first projection plane is the xy plane.5B shows that the cooling pin 140 of the second category, viewed in the first projection direction 150, is inclined at a third angle 170 relative to the vertical direction 135. Since the cooling pin 140 is inclined clockwise, the third angle 170 is a positive angle in the range between 0° and 90°.
[0112] If the cooling pin 140 of the second category is viewed in the direction of the second projection direction 160, the view shown in Fig. 5C is obtained in a second projection plane perpendicular to the second projection direction 160. This second projection plane is the x-z plane. Fig. 5C shows that the cooling pin 140 of the second category, viewed in the second projection direction 160, is inclined at a fourth angle 175 relative to the perpendicular direction 135, namely counterclockwise. Therefore, the fourth angle 175 is a negative angle in the range between 0° and 90°.
[0113] The cooling pin 140 of the second category shown in Figs. 5A to 5C is also a cooling pin that is inclined in two respects, being inclined obliquely relative to the vertical direction 135 both when viewed in the first projection direction 150 and when viewed in the second projection direction 160. As a further example, Fig. 6 shows an oblique image of a cooling pin 180 of a third category together with the coordinate system of Fig. 4, wherein the cooling pin 180 of the third category is oriented obliquely inclined relative to the vertical direction 135 according to a third inclination direction 185.When the cooling pin 180 of the third category is viewed in the first projection direction 150 and in the second projection direction 160, it can be seen that the cooling pin 180 of the third category is oriented in the first projection plane at an angle in the range between 0° and 90° obliquely inclined to the vertical direction 135 and is also oriented in the second projection plane at an angle in the range between 0° and 90° obliquely inclined to the vertical direction 135.
[0114] As a further example, Fig. 7 shows an oblique image of a cooling pin 190 of a fourth category together with the coordinate system of Fig. 4, wherein the cooling pin 190 of the fourth category is oriented at an oblique angle relative to the vertical direction 135 according to a fourth inclination direction 195. If the cooling pin 190 of the fourth category is viewed in the first projection direction 150 and in the second projection direction 160, it can be seen that the cooling pin 190 of the fourth category is oriented at an oblique angle to the vertical direction 135 by a negative angle in the range between 0° and 90° in the first projection plane and is oriented at an oblique angle to the vertical direction 135 by a positive angle in the range between 0° and 90° in the second projection plane.
[0115] Fig. 8 shows a preferred embodiment of the invention. According to this embodiment, a plurality of cooling pins 125 of the first category are arranged along a first straight line 200 that extends along the first cooling wall 50. The cooling pins 125 of the first category are preferably arranged at regular intervals along the first straight line 200. A second straight line 205 runs parallel to the first straight line 200 along the first cooling wall 50 at a certain distance from the first straight line 200. A plurality of cooling pins 210 that are opposite to the cooling pins 125 of the first category are arranged along the second straight line 205. The cooling pins 210 that are opposite to the cooling pins 125 of the first category are preferably arranged at regular intervals along the second straight line 205.
[0116] The cooling pins 125 of the first category are arranged oriented in a first inclination direction 130, wherein the first inclination direction 130 is inclined relative to the direction 135 perpendicular to the first cooling wall 50.
[0117] Viewed in a third projection direction 215, which corresponds to the direction of the first straight line 200, the cooling pins 125 of the first category are arranged at an angle to the vertical direction 135. Also viewed in a fourth projection direction 220, which is orthogonal to both the third projection direction 215 and the vertical direction 135, the cooling pins 125 of the first category are oriented at an angle relative to the vertical 135. The cooling pins 125 of the first category are thus oriented at an angle in two respects. Firstly, when viewed in the third projection direction 215, they are inclined relative to the vertical direction 135, and secondly, when viewed in the fourth projection direction 220, they are inclined relative to the vertical direction 135.
[0118] The cooling pins 210, which are opposite to the cooling pins 125, are aligned in an inclination direction 225, which is opposite to the first inclination direction 130. The following explains what is meant by an opposite inclination direction. Viewed in the third projection direction 215, the opposite cooling pins 210 are inclined in the opposite direction relative to the vertical direction 135 compared to the cooling pins 125 of the first category. In the fourth projection direction 220, however, the opposite cooling pins 210 are inclined at the same angle relative to the vertical direction 135 as the cooling pins 125 of the first category.
[0119] Consequently, an opposite orientation of the opposite cooling pins 210 is to be understood as meaning that, viewed in the third projection direction 215, they are inclined relative to the vertical direction 135 by the opposite angle as the cooling pins 125 of the first category, but viewed in the fourth projection direction, they are inclined in the same direction as the cooling pins 125 of the first category.
[0120] 9A and 9B show a further preferred embodiment of the invention, in which the arrangement of the cooling pins within the cooling channel 35 is determined using a unit cell 230. Fig. 9A shows the structure of the unit cell 230. A second plurality of cooling pins 235 is arranged within the unit cell 230. The cooling pins 235 arranged within the cooling unit cell 230 are designed to extend from the first cooling wall 50 into the interior of the cooling channel 35. The cooling pins of the second plurality of cooling pins 235 are arranged within the unit cell 230 such that a cooling pin 235 does not intersect any other cooling pin of the second plurality of cooling pins 235. The cooling pins of the second plurality of cooling pins 235 may, for example, include one or more cooling pins 125 of the first category and / or one or more cooling pins 140 of the second category.
[0121] Fig. 9B shows the cooling channel 35, which is delimited by the first cooling wall 50 and the second cooling wall 55. Within a partial region of the cooling channel 35, a plurality of mutually identical unit cells 230-1 to 230-4 of the type shown in Fig. 9A are arranged. The unit cells 230-1 to 230-4 are preferably arranged adjacent to one another, preferably in several rows and / or several columns. The height of a unit cell 230 preferably corresponds to the height of the cooling channel 35. The second plurality of cooling pins 235 arranged within each unit cell 230-1 to 230-4 extends from the first cooling wall 50 into the interior of the cooling channel 35.
[0122] According to a first embodiment, the cooling pins of the second plurality of cooling pins 235 do not extend as far as the second cooling wall 55, so that a certain distance exists between the ends of the cooling pins 235 facing away from the first cooling wall 50 and the second cooling wall 55. According to an alternative preferred embodiment, however, the cooling pins of the second plurality of cooling pins 235 extend continuously within the cooling channel 35 from the first cooling wall 50 to the second cooling wall 55. The overlap and, in particular, the interweaving of the cooling pins of different categories in a viewing direction parallel to the first cooling wall 50 is also evident in Figs. 9a and 9b.
[0123] In the embodiment shown in Figs. 9A and 9B, the unit cell 230 serves as a basic design unit with which the arrangement of the cooling pins within the cooling channel 35 can be determined with little effort.
[0124] The features disclosed in the above description, the claims and the drawings may be important both individually and in any combination for the realization of the invention in its various forms.
Claims
PATENT CLAIMS 1. A heat sink (5) for cooling a unit (10) to be cooled, in particular an electrical unit, preferably a semiconductor device, wherein the heat sink (5) has a cooling channel (35) through which coolant, in particular cooling liquid, preferably cooling water, can flow in an intended flow direction, wherein the cooling channel (35) has a first cooling wall (50) on the side of the cooling channel (35) facing the unit to be cooled, wherein a plurality of cooling pins (65) are arranged in the cooling channel (35) or in a partial region of the cooling channel (35), which extend from the first cooling wall (50) into the cooling channel (35), wherein the plurality of cooling pins (65) comprises at least one cooling pin (125) of a first category, which is oriented in a first inclination direction (130) that is inclined obliquely relative to a perpendicular (135) to the first cooling wall (50), wherein the cooling pins of the plurality of cooling pins (65) are arranged so thatthat a cooling pin of the plurality of cooling pins (65) does not intersect any other cooling pin of the plurality of cooling pins (65)., 2. Heat sink (5) according to claim 1, characterized in that - viewed in a first projection direction (150), the first inclination direction (130) is inclined obliquely to the perpendicular (135) to the first cooling wall (50), wherein the first projection direction (150) is the intended flow direction of the coolant, and that - also viewed in a second projection direction (160), the first inclination direction (130) is inclined obliquely to the perpendicular (135) to the first cooling wall (50), wherein the second projection direction (160) is orthogonal both to the intended flow direction and to the perpendicular (135) to the first cooling wall (50).
3. Heat sink (5) according to claim 2, characterized in that, viewed in the first projection direction (150), the first inclination direction (130) in the first projection plane is inclined by a first angle (155) to the Perpendicular (135) to the first cooling wall (50), wherein the first angle (155) is a positive or negative angle in the range between 0° and 90°, more preferably in the range between 10° and 80°, more preferably in the range between 20° and 70°, more preferably in the range between 30° and 60°, more preferably in the range between 35° and 55°, more preferably in the range between 40° and 50°.
4. Heat sink (5) according to claim 2 or claim 3, characterized in that viewed in the second projection direction (160), the first inclination direction (130) in the second projection plane is inclined by a second angle (165) to the perpendicular (135) to the first cooling wall (50), wherein the second angle (165) is a positive or negative angle in the range between 0° and 90°, more preferably in the range between 10° and 80°, more preferably in the range between 20° and 70°, more preferably in the range between 30° and 60°, more preferably in the range between 35° and 55°, more preferably in the range between 40° and 50°.
5. Heat sink (5) according to one of the preceding claims, characterized in that the plurality of cooling pins (65) comprises at least one cooling pin (140) of a second category, which is oriented in a second inclination direction (145) which is inclined relative to the perpendicular (135) to the first cooling wall (50), wherein the second inclination direction (145) is different from the first inclination direction (130).
6. Heat sink (5) according to claim 5, characterized in that - viewed in a first projection direction (150), the second inclination direction (145) is inclined obliquely to the perpendicular (135) to the first cooling wall (50), wherein the first projection direction (150) is the intended flow direction of the coolant, and that - also viewed in a second projection direction (160), the second inclination direction (145) is inclined obliquely to the perpendicular (135) to the first cooling wall (50), wherein the second projection direction (160) is inclined both to the intended flow direction as well as to the perpendicular (135) to the first cooling wall (50).
7. Heat sink (5) according to one of the preceding claims, characterized in that a plurality of cooling pins (125) of the first category are arranged along a first straight line (200) which runs along the first cooling wall (50).
8. Heat sink (5) according to claim 7, characterized in that - viewed in a third projection direction (215), the first inclination direction (130) is inclined by a fifth angle to the perpendicular (135) to the first cooling wall (50), wherein the third projection direction (215) is the direction of the first straight line (200), and that - viewed in a fourth projection direction (220), the first inclination direction (130) is inclined by a sixth angle to the perpendicular (135) to the first cooling wall (50), wherein the fourth projection direction (220) is orthogonal to both the first straight line (200) and the perpendicular (135) to the first cooling wall (50).
9. Heat sink (5) according to claim 7 or claim 8, characterized in that the plurality of cooling pins (65) comprises a plurality of cooling pins (210) which are opposite to the cooling pins (125) of the first category and which are oriented in an inclination direction (225) opposite to the first inclination direction (130), wherein a plurality of the cooling pins (210) which are opposite to the cooling pins (125) of the first category are arranged along a second straight line (205) which runs parallel to the first straight line (200) along the first cooling wall (50).
10. Heat sink (5) according to claim 9, characterized in that - viewed in the third projection direction (215), the inclination direction (225) opposite to the first inclination direction (130) is inclined at a seventh angle to the perpendicular (135) to the first cooling wall (50), wherein the third projection direction (215) is the direction of the first straight line (200), and that - viewed in the fourth projection direction (220), the inclination direction (225) which is opposite to the first inclination direction (130) is inclined at an eighth angle to the perpendicular (135) to the first cooling wall (50), wherein the fourth projection direction (220) is orthogonal to both the first straight line (200) and the perpendicular (135) to the first cooling wall (50), wherein the seventh angle corresponds to the fifth angle with a negative sign and the eighth angle corresponds to the sixth angle.
11. Heat sink (5) according to one of the preceding claims, characterized in that the cooling channel (35) has a second cooling wall (55) on the side of the cooling channel (35) opposite the first cooling wall (50).
12. Heat sink (5) according to claim 11, characterized in that the cooling pins of the plurality of cooling pins (65) extend continuously from the first cooling wall (50) to the second cooling wall (55).
13. Heat sink (5) according to one of the preceding claims, characterized in that the heat sink (5) is a micro heat sink and that the unit to be cooled is an electronic component.
14. Heat sink (5) according to one of the preceding claims, characterized in that the heat sink (5) is made of copper.
15. Heat sink (5) according to one of the preceding claims, characterized in that the cooling pins of the heat sink (5) are manufactured by means of an additive manufacturing process, in particular by means of selective laser melting (SLM).
16. Heat sink (5) according to one of the preceding claims 5 to 15, characterized in that the plurality of cooling pins (65) is arranged such that a cooling pin (125) of the first category is aligned with a cooling pin (140) of the second category at a viewing angle parallel to the cooling wall (50), in particular in a viewing angle of the coolant flow direction (121), overlaps.
17. Heat sink (5) according to claim 16, characterized in that the plurality of cooling pins (65) is arranged such that a cooling pin (125) of the first category is intertwined with two cooling pins (140) of the second category at a viewing angle parallel to the cooling wall (50), in particular at a viewing angle of the coolant flow direction (121).
18. Electrical power converter (4) for an industrial process arrangement (1), preferably a plasma process arrangement or heating arrangement, comprising: - a heat sink (5) according to one of the preceding claims, - a printed circuit board (75), - a unit (10) to be cooled, in particular an electrical unit, preferably a semiconductor device, preferably comprising a power semiconductor component, - further electronic components (8a, 8b, 8c), wherein the further electronic components (8a, 8b, 8c) and the unit to be cooled (10) are arranged on or at a printed circuit board (75) and are connected by electrical contacts, wherein the unit to be cooled (10) has a fixed, in particular material-locking, connection with the heat sink (5).
19. A method for designing a heat sink (5) for cooling a unit to be cooled, wherein the heat sink (5) has a cooling channel (35) through which coolant can flow in a predetermined flow direction, wherein the cooling channel (35) has a first cooling wall (50) on the side of the cooling channel (35) facing the unit to be cooled, characterized by the following step: Arranging a plurality of cooling pins (65) in the cooling channel (35) which extend from the first cooling wall (50) into the cooling channel (35), wherein the plurality of cooling pins (65) comprises at least one cooling pin (125) of a first category, which is oriented in a first inclination direction (130) which is inclined relative to a perpendicular (135) to the first cooling wall (50), wherein the cooling pins of the plurality of cooling pins (65) are arranged such that one cooling pin of the plurality of cooling pins (65) does not intersect any other cooling pin of the plurality of cooling pins (65).
20. A method for producing a heat sink (5) for cooling a unit to be cooled, wherein the heat sink (5) has a cooling channel (35) through which coolant can flow in a predetermined flow direction, wherein the cooling channel (35) has a first cooling wall (50) on the side of the cooling channel (35) facing the unit to be cooled, characterized by the following step: Producing a plurality of cooling pins (65) within the cooling channel (35), which extend from the first cooling wall (50) into the cooling channel (35), by means of an additive method, wherein the plurality of cooling pins (65) comprises at least one cooling pin (125) of a first category, which is oriented in a first inclination direction (130) which is inclined obliquely relative to a perpendicular (135) to the first cooling wall (50), wherein the cooling pins of the plurality of cooling pins (65) are arranged such that one cooling pin of the plurality of cooling pins (65) does not intersect any other cooling pin of the plurality of cooling pins (65).