Heat sink for a circuit breaker

Abstract

The present invention relates to a heat sink (1) for cooling a circuit breaker (300), wherein the heat sink (1) can be positioned at a cooling position of the circuit breaker (300), wherein the heat sink (1) has at least one cooling region (111, 211) with a plurality of cooling pins (112, 212), wherein the cooling pins (112, 212) are arranged at least partially within a heat sink housing (110, 210) and wherein the cooling pins (112, 212) can be surrounded by a cooling gas from the outside.

Description

[0001] The present invention relates to a heat sink for a circuit breaker. The present invention further relates to a circuit breaker equipped with such a heat sink.

[0002] The transfer of electrical energy through a circuit breaker generates a significant amount of heat. International design and testing standards specify the permissible temperature limits at certain locations within the circuit breaker to ensure safe operation. To comply with these temperature limits, circuit breakers typically incorporate cooling elements such as heat sinks and special modifications or designs to the current path to increase their surface area and better dissipate heat to the surrounding air. Traditionally, heat sinks and current path configurations incorporate elements in the form of fins or ribs with a rounded surface to reduce the electric field strength. This allows demanding dielectric requirements to be met while also providing cooling.

[0003] However, this state of the art still has potential for improvement. In particular, such solutions have potential for improvement in terms of cooling efficiency.

[0004] The object of the present invention is to at least partially overcome the disadvantages known from the prior art. In particular, the object of the present invention is to provide a solution that allows good cooling efficiency of circuit breakers while simultaneously enabling good dielectric shielding.

[0005] The object is achieved according to the invention at least in part by a heat sink having the features of claim 1. The object is further achieved according to the invention at least in part by a circuit breaker having the features of claim 9. Preferred embodiments of the invention are described in the subclaims, in the description or the figures, wherein further features described or shown in the subclaims or in the description or the figures can individually or in any combination constitute an object of the invention, unless the context clearly indicates the opposite.

[0006] A heat sink for cooling a circuit breaker is described, wherein the heat sink can be positioned on a heat dissipation path of a circuit breaker, wherein the heat sink has at least one cooling region with a plurality of cooling pins, wherein the cooling pins are arranged outwardly at least partially within a heat sink housing and wherein a cooling gas can flow around the cooling pins.

[0007] Such a heat sink offers significant advantages over state-of-the-art solutions.

[0008] The heat sink thus serves to cool a circuit breaker. In principle, the circuit breaker can be designed in a conventional manner and have two contacts that can be connected and disconnected, for example, with one contact being fixed and a second contact being movable. This allows for switching functionality. Furthermore, the circuit breaker can, for example, form a gas-insulated switchgear (GIS). Due to the presence of insulating gas, such as sulfur hexafluoride or halogen-free insulating gases, such switchgears enable short insulation distances and thus a comparatively compact design.

[0009] It is known that such circuit breakers heat up the current-carrying parts, especially the main current paths, during operation. This heating results primarily from the power loss of the main current paths due to their resistance. Accordingly, cooling is necessary for electrical circuit breakers.

[0010] To achieve this, the heat sink can be positioned at a cooling position of a circuit breaker, for example, a vacuum interrupter. A cooling position can be understood, in particular, as a position at which cooling of the circuit breaker or vacuum tube is possible. For example, a cooling position is part of a cooling path.

[0011] The heat sink comprises at least one cooling region with a plurality of cooling pins. For example, the heat sink or cooling region comprises at least ten, for example at least fifteen, cooling pins, also referred to as cooling pins. These can be easily adapted to the desired application area or the desired cooling performance by selecting the diameter and / or length, for example, they can have a diameter in a range of 1...10 mm and a length in a range of 10...300 mm. The cooling pins are expediently made of a material with good thermal conductivity, such as a metal, preferably copper or aluminum. However, the advantages of the described heat sink are not limited to these materials. In particular, the cooling pins can run at least partially, for example all of the cooling pins, in parallel.However, the specific arrangement of the cooling pins can be chosen depending on the specific application, as will be understood by the person skilled in the art.

[0012] The cooling pins are at least partially arranged within a heat sink housing and are thus at least partially covered from the outside by the housing. This enables advantageous dielectric shielding.

[0013] Furthermore, the cooling pins can be surrounded by a cooling gas, in the simplest case, air, from the outside, i.e., from outside the heat sink housing. This allows the cooling pins to serve as passive cooling structures, i.e., cooling in particular by convection. Alternatively, however, it is also possible, and encompassed by the present invention, for cooling to be supported by a fan, thus actively directing an air flow to the cooling pins and surrounding them.

[0014] The heat sink described above allows for particularly effective cooling. The multiple cooling pins allow for a particularly large cooling surface even in a small installation space. Accordingly, improved cooling performance can be achieved with the same installation space compared to state-of-the-art solutions, or a more compact design can be achieved with the same cooling performance.

[0015] In detail, improved cooling performance can be achieved by increasing the cooling surface and simultaneously increasing heat dissipation by convection, particularly in areas close to the heat source or at a connection point to the vacuum interrupter.

[0016] The design with cooling pins can be implemented in a highly adaptable and variable manner, thus allowing adaptation to desired specific applications or cooling geometries. The cooling pins can be aligned in all three spatial dimensions, in particular starting from a connection area to a pole head of a switching tube, in the opposite direction, or even at right angles to it. This can also be done jointly within one embodiment.

[0017] The spacing, length, and diameter of the cooling pins can vary. If necessary, the cooling pins can also be arranged in any shape, such as non-linear or curved, such as wave-like.

[0018] In this regard, it should be noted that the function of the heat sink is independent of the heat sink's manufacturing process. Through the use of innovative processes such as additive manufacturing (AM), cooling pins rotated vertically by 90° can be manufactured more easily and in mass production. In principle, a wide variety of structures can be created or are being created without any problems.

[0019] Perforation, i.e., at least partial provision of through-holes, also known as flow channels, of the heat sink or cooling pins can be implemented as desired, regardless of the exact position. This can further improve convection and thus cooling by allowing the cooling gas to flow not only around the cooling pins, but also through them.

[0020] Another advantage of using perforated cooling pins is that it can reduce the amount of material used.

[0021] Preferably, the heat sink is formed from a first heat sink part and a second heat sink part, wherein the first heat sink part has first cooling pins and the second heat sink part has second cooling pins. Particularly in this embodiment, the specific configuration of the cooling pins themselves, but also in relation to one another, can be freely selected. Furthermore, simple and problem-free assembly is enabled.

[0022] The first and second cooling pins can be of the same or different design.

[0023] It may further be preferred for the first cooling pins and the second cooling pins to be arranged coaxially and extend in opposite directions. Depending on the specific shape and positioning, this configuration can enable particularly high stability or particularly good heat dissipation.

[0024] For example, if the ends of the first cooling pins and the ends of the second cooling pins at least partially touch each other, particularly good mechanical stability can be achieved. Furthermore, improved thermal conductivity of the heat sink can be achieved.

[0025] In this embodiment, the lengths of the cooling pins are thus adapted to one another in such a way that, when the heat sink parts are assembled, the cooling pin ends lie against one another.

[0026] For example, the contact surfaces of the cooling pins can be adapted to each other. In this configuration, contact in the sense of a "tongue and groove connection" can be enabled, so that, for example, one cooling pin end at least partially dips into or extends into the end of the other cooling pin. This can be achieved, for example, by having one cooling pin end with a concave shape and the opposite cooling pin end with a convex shape.

[0027] Alternatively or additionally, the ends of the first cooling pins and the ends of the second cooling pins can be at least partially spaced apart from one another. In this embodiment, the surface area of the cooling pins available for cooling can be particularly large, so that cooling can be particularly effective.

[0028] Further preferably, the first cooling pins can have different lengths, and the second cooling pins can have different lengths, so that the first cooling pins extend at least partially between the second cooling pins. In this embodiment, the stability of the heat sink can also be particularly high.

[0029] In principle, all of the aforementioned configurations of the first and second cooling pins - in particular with touching cooling pins, with spaced cooling pins, with different lengths of the cooling pins, so that the first cooling pins run at least partially between the second cooling pins - are possible regardless of whether the heat sink is designed in one piece or in several pieces.

[0030] It may further be preferred for the heat sink to have a heat sink housing on which cooling structures are arranged on the outside. In this embodiment, cooling within the heat sink housing by the cooling pins can thus be combined with cooling outside the heat sink housing. The external cooling structures can also be formed by cooling pins or, preferably, by cooling fins. This embodiment also allows for particularly effective cooling.

[0031] For further advantages and technical features of the heat sink, please refer to the description of the circuit breaker, the figures and the description of the figures.

[0032] Also described is a circuit breaker comprising a heat sink for cooling the circuit breaker, characterized in that the heat sink is designed as described above.

[0033] By equipping a circuit breaker with a heat sink, the advantages described above can be achieved. Particularly effective cooling can be achieved while maintaining a very compact design.

[0034] Particularly preferably, the heat sink can be arranged on a pole head of the circuit breaker or a vacuum interrupter of the circuit breaker. Cooling can be particularly useful at such locations. Large amounts of heat are generated particularly at such locations, so cooling at the pole heads is of great importance. Thus, the heat generated in a vacuum interrupter can be effectively dissipated, particularly at these locations.

[0035] For example, the circuit breaker can be part of a medium-voltage switchgear or a high-voltage switchgear. A medium-voltage switchgear is defined as a switchgear capable of switching voltages from approximately 1 kV up to 60 kV. Furthermore, a high-voltage switchgear can be defined as a switchgear capable of switching voltages above 60 kV.

[0036] For further advantages and technical features of the circuit breaker, please refer to the description of the heat sink, the figures and the description of the figures.

[0037] Further details, features, and advantages of the subject matter of the invention will become apparent from the dependent claims and the following description of the figures. The figures show: Fig. 1 is a diagram showing a two-part heat sink for a circuit breaker according to an embodiment of the present invention; Fig. 2 a representation showing a first heat sink part of a heat sink according to Fig. 1; Fig. 3 a representation showing the heat sink from Fig. 1 on a fixed contact of a circuit breaker; Fig. 4 a representation showing the heat sink from Fig. 1 on a moving contact of a circuit breaker; and Fig. 5 a representation of a cooling pin for a heat sink.

[0038] In the Fig. 1 is a diagram showing a heat sink 1 for a circuit breaker according to an embodiment of the present invention.

[0039] The heat sink 1 is formed in two parts and comprises a first heat sink part 100 formed as a first heat sink half-shell and a second heat sink part 200 formed as a second heat sink half-shell. The heat sink parts 100, 200 have a heat sink housing 110, 210, which partially enclose a cooling region 111, 112, in which first cooling pins 112 of the first heat sink part 100 and second cooling pins 212 of the second heat sink part 200 are arranged. A first cooling pin 112 is in the Fig. 5, wherein the first cooling pin 112 in this embodiment has a plurality of flow channels 113 for improved convection.

[0040] The heat sink housings 110, 210 have a smooth outer side surface 114, 214 at one end region, which extends to an end face 116, 216. The end faces 116, 216 face one another and can be spaced apart from one another, in particular by a thin gap, or they can lie adjacent to one another. Furthermore, a first side surface 118 as a component of the first heat sink part 100 and a second side surface 218 of the second heat sink part 200 extend in a plane perpendicular to the smooth outer side surfaces 114, 214. The side surfaces 118, 218 are provided with cooling fins 120, 220, which serve for external cooling.

[0041] With regard to the cooling pins 112, 212, as indicated above, it is shown that they are arranged at least partially within the heat sink housing 110, 210 and can be flowed around from the outside. This enables purely passive cooling as well as active cooling by means of a fan.

[0042] The first cooling pins 112 and the second cooling pins 212 are arranged coaxially and extend in opposite directions by being attached to the opposite side parts 122, 222 having the side surfaces 118, 218, wherein the ends of the first cooling pins 112 and the ends of the second cooling pins 212 touch each other.

[0043] It is further shown that the first cooling pins 112 have different lengths and that the second cooling pins 212 have different lengths, so that the first cooling pins 112 extend at least partially between the second cooling pins 212 and the second cooling pins 212 extend at least partially between the first cooling pins 112.

[0044] The first heat sink part 100 and the second heat sink part 200 have a passage area 124, 224 through which at least part of a pole head 310 of a vacuum interrupter 312 of the circuit breaker 300 can extend. Accordingly, the heat sink 1 can be positioned on a heat dissipation path of the vacuum interrupter 312. Mounting holes 126 are provided for attaching the heat sink 1 to the pole head 310. Furthermore, a smooth inner wall surface 128 can be provided.

[0045] The passage areas 124, 224 are separated from the cooling areas 111, 211 by a partition 130, 230, referred to as a central wall. The mutually facing end faces 132 of the partitions 130, 230 can be adjacent to one another or spaced apart. Contact between the end faces 132 of the partitions 130, 230 is advantageous for heat conduction and thus the cooling properties and mechanical stability of the illustrated design.

[0046] In the Fig. 3 shows a portion of a vacuum interrupter 312. A fixed contact rod 314 is shown in the vacuum interrupter 312, which extends through a fixed contact flange 316 to a fixed contact terminal 318. A temperature measuring point 320 is arranged on a fixed contact heat sink 322, wherein the fixed contact heat sink 322 can be a heat sink 1 as described above. In particular, at these positions, it is possible to effectively measure whether cooling of the circuit breaker 300 or the vacuum interrupter 312 is sufficient.

[0047] The Fig.Figure 4 shows the moving contact connection 324 of the vacuum interrupter 312. The moving contact rod 326 is shown in detail, which extends within the moving contact flange 328 and is surrounded by a bellows 330 between the moving contact rod 326 and the moving contact flange 328 to compensate for movement. The moving contact rod 326 also lies in a moving contact mount 332, against which a moving contact heat sink 334 rests. The moving contact heat sink 334 can be a heat sink 1, as described above.

[0048] A current band 336 is also shown, which contacts the moving contact rod 326 and which is fixed by a current band fastening means 338.

[0049] A temperature measuring point 340 is provided on the moving contact rod 326 and adjacent to the moving contact heat sink 334. In particular, at these positions, it is possible to effectively measure whether cooling of the circuit breaker 300 or the vacuum interrupter 312 is sufficient.

[0050] The above-described heat sink 1 has a design with cooling pins 112, 212 having a raised cooling surface in addition to cooling fins 120, 220, while simultaneously providing dielectric shielding in the switch compartment. The improved heat dissipation at the pole head 310 of the vacuum interrupter 312 results in improved cooling performance in the circuit breaker 300 and the switchgear assembly. The temperature improvement achieved by the shown design is, for example, 2% or more, preferably 5% or more, at the selected measuring point 320, 340.

[0051] Regardless of the grammatical gender of a particular term, persons with male, female or other gender identity are included.

[0052] Although the invention has been illustrated and described in detail by the preferred embodiments, the invention is not limited to the disclosed examples and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention.

Claims

[1] Heat sink (1) for cooling a circuit breaker (300), wherein the heat sink (1) can be positioned at a cooling position of the circuit breaker (300), characterized by that the heat sink (1) has at least one cooling region (111, 211) with a plurality of cooling pins (112, 212), wherein the cooling pins (112, 212) are arranged at least partially within a heat sink housing (110, 210) and wherein the cooling pins (112, 212) can be surrounded by a cooling gas from the outside. [2] Heat sink (1) according to claim 1, characterized by that the heat sink (1) is formed from a first heat sink part (100) and a second heat sink part (200), wherein the first heat sink part (100) has first cooling pins (112) and wherein the second heat sink part (200) has second cooling pins (212). [3] Heat sink (1) according to claim 2, characterized bythat the first cooling pins (112) and the second cooling pins (212) are arranged coaxially and run in opposite directions. [4] Heat sink (1) according to claim 2 or 3, characterized by that the ends of the first cooling pins (112) and the ends of the second cooling pins (212) at least partially touch each other. [5] Heat sink (1) according to one of claims 2 to 4, characterized by that the ends of the first cooling pins (112) and the ends of the second cooling pins (212) are at least partially spaced apart from one another. [6] Heat sink (1) according to one of claims 2 to 5, characterized by that the first cooling pins (112) have different lengths and that the second cooling pins (212) have different lengths, so that the first cooling pins (112) run at least partially between the second cooling pins (212) and wherein the second cooling pins (212) run at least partially between the first cooling pins (112). [7] Heat sink (1) according to one of claims 1 to 6, characterized by that the heat sink (1) has a heat sink housing (110, 210) on which cooling structures are arranged on the outside. [8] Heat sink (1) according to one of claims 1 to 7, characterized by that the cooling pins (112, 212) are at least partially provided with flow channels (113). [9] Circuit breaker (300), comprising a heat sink (1) for cooling the circuit breaker (300), characterized by that the heat sink (1) is designed according to one of claims 1 to 8. [10] Circuit breaker (300) according to claim 9, characterized by that the heat sink (1) is arranged on a pole head (310) of the circuit breaker (300).

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