Heat dissipation device and transformation system

Abstract

The utility model relates to a heat dissipation device and a transformation system. The heat dissipation device comprises a base and a cover shell, the cover shell is arranged on the base and comprises an inner shell and an outer shell, the inner shell and the base jointly define a sealing cavity used for containing the transformer, the outer shell is arranged outside the inner shell in a covering mode, the outer shell and the inner shell jointly define a heat dissipation cavity, the interior of the heat dissipation cavity is in a vacuum state, and part of the space is filled with cooling liquid capable of being heated to evaporate. According to the heat dissipation device and the voltage transformation system, the good waterproof sealing effect can be achieved, and meanwhile the good heat dissipation effect is achieved.

Description

Technical Field

[0001] This application relates to the field of transformer sealing and cooling technology, and in particular to a heat dissipation device and a transformer system. Background Technology

[0002] Three-dimensional wound core dry-type transformers offer significant advantages in terms of high efficiency, energy saving, safety, and reliability. Currently, three-dimensional wound core dry-type transformers, which have relatively high environmental requirements, are generally only used in indoor distribution rooms (often located in basements) or outdoor pavilion-style substations. However, when urban flooding occurs due to typhoons or heavy rains, three-dimensional wound core dry-type transformers located in basements are easily affected by water immersion and can burn out. Therefore, waterproof sealing of three-dimensional wound core dry-type transformers is crucial. However, tight sealing often affects heat dissipation. Three-dimensional wound core dry-type transformers generate a large amount of heat during operation; if heat dissipation is not timely, heat will accumulate, which is extremely dangerous.

[0003] However, transformers in related technologies often fail to achieve both waterproofing and good heat dissipation. Utility Model Content

[0004] Based on this, a heat dissipation device and a transformer system are provided to achieve both better waterproof sealing and better heat dissipation.

[0005] According to one aspect of this application, a heat dissipation device is provided, the heat dissipation device comprising:

[0006] Base; and

[0007] A housing is disposed on the base. The housing includes an inner shell and an outer shell. The inner shell and the base together define a sealed cavity for accommodating the transformer. The outer shell covers the inner shell and together with the inner shell defines a heat dissipation cavity. The heat dissipation cavity is in a vacuum state, and part of the space is filled with a cooling liquid that can be heated and evaporated.

[0008] In one embodiment, the outer casing has an outer side facing away from the inner casing, and a plurality of heat dissipation components are provided on the outer side of the outer casing.

[0009] In one embodiment, the housing includes a sidewall and a top wall disposed on the sidewall, the top wall and the base being located at opposite ends of the sidewall along a first direction;

[0010] The plurality of heat dissipation components include a plurality of first heat dissipation components, which are spaced apart along the first direction, and the first heat dissipation components are arranged in a ring around an axis parallel to the first direction on the outer side surface of the sidewall.

[0011] In one embodiment, the plurality of heat sinks further includes a plurality of second heat sinks, which are arranged in an array on the top wall and located on the outer surface of the top wall.

[0012] In one embodiment, the heat dissipation device further includes a plurality of lifting components, which are disposed on the top wall and located on the side of the top wall opposite to the base.

[0013] In one embodiment, the plurality of lifting components are arranged around the periphery of the plurality of second heat sinks about an axis parallel to the first direction.

[0014] In one embodiment, the projection of the inner shell onto a reference plane perpendicular to the first direction is circular, the projection of the outer shell onto the reference plane is circular, and the projection of the outer shell onto the reference plane overlaps the projection of the inner shell onto the reference plane.

[0015] Wherein, the first direction is parallel to the direction in which the base points towards the top of the cover.

[0016] In one embodiment, at least one wire hole is provided on the base in the direction from the top of the housing, and the wire hole is connected to the sealed cavity and the external environment respectively.

[0017] In one embodiment, the heat dissipation device includes a first fan disposed within the sealed cavity and located on the inner shell; and / or

[0018] The heat dissipation device includes a second fan, which is located inside the sealed cavity and on the transformer.

[0019] According to another aspect of this application, a transformer system is provided, including a transformer and a heat dissipation device as described in any of the above embodiments, wherein the transformer is disposed within the heat dissipation device.

[0020] The aforementioned heat dissipation device utilizes the principle of heat pipes. During transformer operation, the heat generated by the transformer is transferred to the inner shell of the casing via air. Subsequently, a heat dissipation cavity filled with cooling liquid and in a vacuum state forms a heat pipe. When the inner shell is heated, the heat pipes operate, causing the cooling liquid in the heat dissipation cavity to evaporate into steam, carrying away heat. The steam flows upward to the top of the heat dissipation cavity, where it condenses back into liquid upon cooling. Simultaneously, it releases heat to the external environment through the outer shell. The liquid flows back into the tank under its own gravity, thus completing a closed loop, or cooling and heat dissipation cycle. This transfers the heat dissipated by the transformer to the external environment through the casing, achieving heat dissipation. The heat dissipation device of this application forms a sealed cavity between the casing and the base to house the transformer, reducing the risk of water immersion and damage to the transformer, thus facilitating waterproof protection. Simultaneously, utilizing the heat pipe principle to dissipate heat from the sealed transformer meets the transformer's waterproof requirements while providing excellent heat dissipation. Furthermore, it eliminates the need for other water-cooling or air-cooling structures, resulting in a simple structure that is conducive to miniaturization. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the heat dissipation device in one embodiment of this application.

[0022] Figure 2 for Figure 1 A top view of the heat dissipation device housing in the illustrated embodiment.

[0023] Figure 3 for Figure 2 A cross-sectional view along the AA direction.

[0024] Figure 4 for Figure 1 Side view of the housing of the heat dissipation device in the illustrated embodiment.

[0025] Figure 5 This is a schematic diagram of a transformer mounted on a base in one embodiment of this application.

[0026] Explanation of icon numbers:

[0027] 10. Heat dissipation device;

[0028] 100. Base; 110. Cable guide hole;

[0029] 200, casing; 210, inner shell; 220, outer shell; 221, side wall; 222, top wall; 230, first heat sink; 240, second heat sink; 250, sealing cavity; 260, heat dissipation cavity;

[0030] 300. Lifting component; 400. Transformer; 410. Base; 420. Transformer body; 421. Three-dimensional wound core; 422. Coil; 423. Clamping structure; 424. Lead wire; 430. Isolation beam; 500. Elevator;

[0031] F1, First Direction. Detailed Implementation

[0032] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0033] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0034] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0035] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0036] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0037] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0038] Three-dimensional wound-core dry-type transformers offer significant advantages in terms of high efficiency, energy saving, safety, and reliability. They overcome the problems of oil leakage, rusting, and other issues common in oil-immersed transformers, reducing routine maintenance and eliminating the risk of combustion or explosion due to product malfunctions. They possess advantages in performance, production cost, and economic efficiency. Currently, three-dimensional wound-core dry-type transformers, which have relatively high environmental requirements, are generally only used in indoor distribution rooms or outdoor pavilion-style substations.

[0039] However, in recent years, typhoons and torrential rains have led to increasingly frequent urban flooding. Besides flood-prone areas, old urban areas are also severely affected by flooding. In urban power distribution networks, indoor distribution rooms often use three-dimensional wound-core dry-type transformers, and these rooms are generally located in basements to save space. However, this brings another problem: when the city floods, these three-dimensional wound-core dry-type transformers located in basements are easily damaged by water and burned out, leading to power outages. Furthermore, they are difficult to replace quickly, resulting in huge economic losses. In addition, restoring power requires a large amount of manpower and resources, severely impacting the lives and livelihoods of the people.

[0040] Therefore, it is necessary to develop a new type of three-dimensional wound core dry-type transformer to expand its application scenarios, enabling it to operate safely underwater, underground, or in confined environments, and further enhance its market competitiveness.

[0041] Based on this, this application provides a heat dissipation device and a transformer system that can simultaneously provide waterproofing and heat dissipation for the transformer, enabling the transformer to have a certain degree of waterproofing and resist damage caused by flooding, while also having a better heat dissipation effect.

[0042] See Figure 1 , Figure 2 and Figure 3 As shown, Figure 1 This is a schematic diagram of the structure of the heat dissipation device 10 in one embodiment of this application. Figure 2 for Figure 1 A top view of the housing 200 of the heat dissipation device 10 in the illustrated embodiment. Figure 3 for Figure 2 A cross-sectional view along the AA direction.

[0043] The heat dissipation device 10 provided in this application includes a base 100 and a cover 200 disposed on the base 100. The cover 200 includes an inner shell 210 and an outer shell 220. The inner shell 210 and the base 100 together define a sealed cavity 250 for accommodating the transformer 400. Air insulation is used between the transformer 400 and the heat dissipation device 10, or between the transformer 400 and the base 100 and the cover 200. The sealed cavity 250 provides sealing protection for the transformer 400, reducing the risk of water immersion and damage to the transformer 400 from the external environment, thus facilitating waterproof protection of the transformer 400. Simultaneously, it also provides windproof, dustproof, external impactproof, and foreign object ingressproof protection for the transformer 400.

[0044] The outer shell 220 covers the inner shell 210 and together they define a heat dissipation cavity 260. The heat dissipation cavity 260 is in a vacuum state, and part of the space is filled with a cooling liquid that can evaporate upon heating. This arrangement utilizes the principle of heat pipes. When the transformer 400 is running, the heat generated by the transformer 400 is transferred to the inner shell 210 of the outer shell 200 through the air. Subsequently, the heat dissipation cavity 260, filled with cooling liquid and in a vacuum state, forms a heat pipe. When the inner shell 210 is heated, the heat pipes operate, and the cooling liquid in the heat dissipation cavity 260 evaporates into vapor, carrying away heat. The vapor flows upward to the top of the heat dissipation cavity 260, where it condenses into liquid upon cooling. Simultaneously, it releases heat to the external environment through the outer shell 220. The liquid flows back into the housing under its own gravity, thus completing a closed loop, or a cooling and heat dissipation loop. This transfers the heat dissipated by the transformer 400 to the external environment outside the outer shell 200, achieving heat dissipation.

[0045] The heat dissipation device 10 of this application can protect the transformer 400 by forming a sealed cavity 250 with the cover 200 and the base 100, and then dissipate heat from the sealed transformer 400 by using the heat pipe principle. Thus, while meeting the waterproof requirements of the transformer 400, it has a better heat dissipation effect. Moreover, there is no need to set up other water cooling or air cooling structures, the structure is simple, and it is conducive to miniaturization design.

[0046] In some embodiments, such as Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the outer casing 220 has an outer side facing away from the inner casing 210, and multiple heat dissipation components are provided on the outer side of the outer casing 220. The heat dissipation components help to increase the heat exchange efficiency between the inside of the sealed cavity 250 and the external environment. That is, when the transformer 400 is working, it generates heat, which is transferred to the inner casing 210 and the heat dissipation cavity 260. The cooling liquid in the heat dissipation cavity 260 evaporates due to the heat, and the evaporated vapor flows upward to the top of the heat dissipation cavity 260. Under the heat exchange action of the heat dissipation fins, it condenses into liquid and releases heat to the outer casing 220 and the heat dissipation components. In this way, heat exchange is achieved, and heat dissipation of the cavity is realized.

[0047] In this embodiment, the heat sink can be a sheet-like heat sink to increase the contact area between the heat sink and the external environment, thereby further improving the heat exchange efficiency.

[0048] In some embodiments, see Figure 1-4 As shown, the outer casing 220 includes a side wall 221 and a top wall 222 disposed on the side wall 221. The top wall 222 and the base 100 are respectively located at both ends of the side wall 221 along the first direction F1. Multiple heat dissipation components include multiple first heat dissipation components 230, which are spaced apart along the first direction F1 and are arranged in a ring around an axis parallel to the first direction F1 on the outer surface of the side wall 221. It can be understood that as the vapor from the heated cooling liquid flows upward, the multiple layers of first heat dissipation components 230 arranged along the first direction F1 exchange heat with the vapor layer by layer, causing the vapor to condense into liquid. The arrangement of multiple first heat dissipation components 230 is beneficial for cooling the vapor during its upward flow, thus improving the heat dissipation efficiency within the sealed cavity 250.

[0049] In some embodiments, continue reading Figure 1-4As shown, the multiple heat sinks also include multiple second heat sinks 240, which are arrayed on the top wall 222 and located on the outer surface of the top wall 222. It can be understood that the vapor from the heated cooling liquid flows upward to the top of the heat dissipation cavity 260, where it undergoes heat exchange with the multiple second heat sinks 240 and condenses into liquid. In conjunction with the first heat sink 230 on the side wall 221 and the second heat sinks 240 on the top wall 222, heat exchange with the vapor is comprehensive and stable, improving the efficiency of vapor condensation into liquid, and thus improving the heat dissipation efficiency of the sealed cavity 250.

[0050] In some embodiments, such as Figure 1-4 As shown, the heat dissipation device 10 also includes multiple lifting components 300, which are disposed on the top wall 222 of the housing 220 and located on the side of the top wall 222 away from the base 100. The lifting components 300 facilitate the lifting and transportation of the heat dissipation device 10, and also facilitate the lifting of the housing 200 after the housing 200 and the base 100 are relatively disassembled, thus improving the convenience of transportation.

[0051] In some embodiments, such as Figure 1 Multiple lifting components 300 are arranged around the periphery of multiple second heat dissipation components 240, around an axis parallel to the first direction F1. This facilitates improved stability during lifting and transportation.

[0052] In some embodiments, such as Figure 1 The projection of the inner shell 210 onto the reference plane perpendicular to the first direction F1 is circular, and the projection of the outer shell 220 onto the reference plane is also circular. In other words, both the inner shell 210 and the outer shell 220 can be cylindrical structures. In this embodiment, the inner shell 210 and the outer shell 220 can also be columnar structures, without further restrictions.

[0053] In this embodiment, the projection of the outer shell 220 onto the reference plane covers the projection of the inner shell 210 onto the reference plane. The first direction F1 is parallel to the direction from the base 100 towards the top of the cover 200. That is, both the inner shell 210 and the outer shell 220 can be cylindrical structures with radial dimensions that gradually increase or decrease along the first direction F1. For example, the radial dimension of the inner shell 210 gradually increases along the first direction F1 away from the base 100, while the radial dimension of the outer shell 220 gradually decreases along the first direction F1 away from the base 100, thereby facilitating the containment of more cooling liquid and improving heat dissipation efficiency. The radial dimensions of the inner shell 210 and the outer shell 220 can also be designed separately according to actual needs; no further restrictions are imposed here.

[0054] In some embodiments, see Figure 5 As shown, Figure 5This is a schematic diagram of a transformer 400 mounted on a base 100 in one embodiment of this application. Along the direction from the base 100 to the top of the housing 200, at least one wire-passing hole 110 is provided on the base 100, which connects to the sealed cavity 250 and the external environment. It can be understood that the wire-passing hole 110 is used to pass wires or the like, enabling electrical connection between the transformer 400 inside the sealed cavity 250 and external equipment.

[0055] In this embodiment, a sealing element can be provided at the wire passage hole 110. After the wire or other wire passes through the wire passage hole 110, the sealing element seals the wire at the wire passage hole 110 and the wire at the wire passage hole 110, thereby improving the sealing performance of the sealing cavity 250 and reducing the risk of water damage to the transformer 400.

[0056] In some embodiments, the base 100 is provided with studs, and the transformer 400 is mounted on the base plate by means of studs. The transformer 400 can also be directly welded to the base 100 by welding.

[0057] In some embodiments, the heat dissipation device 10 further includes a riser 500, which is disposed on the side of the base 100 opposite to the housing 200. The riser 500 is made of channel steel or bent plate. The riser 500 can separate the heat dissipation device 10 from the ground, reducing the risk of water immersion and erosion of the heat dissipation device 10 and reducing the risk of water entering the sealed cavity 250. In this embodiment, a connecting structure or bolt holes can also be provided on the riser 500 to facilitate the installation of the riser 500 on other structural components or foundations, thereby facilitating the installation of the heat dissipation device 10 on other structural components.

[0058] In some embodiments, the heat dissipation device 10 further includes a first fan, which is disposed within the sealed cavity 250 and located on the inner shell 210. The first fan can blow air into the transformer 400 within the sealed cavity 250 to further cool the transformer 400, and can also increase the airflow rate within the sealed cavity 250 to improve the cooling effect on the transformer 400.

[0059] In some embodiments, the heat dissipation device 10 further includes a second fan, which is disposed within the sealed cavity 250 and located on the transformer 400. That is, another fan, different from the first fan, can be installed on the transformer 400. The second fan can also blow air onto the transformer 400 within the sealed cavity 250, further cooling the transformer 400 and increasing the airflow rate within the sealed cavity 250, thereby improving the cooling effect on the transformer 400.

[0060] According to another aspect of this application, a transformer system is also provided, comprising a transformer 400 and a heat dissipation device 10 as described in any of the above embodiments, wherein the transformer 400 is disposed within the heat dissipation device 10. The heat dissipation device 10 cools the transformer 400 and simultaneously keeps the transformer 400 in a sealed state, improving the waterproof performance of the transformer 400 and reducing the risk of water damage to the transformer 400.

[0061] See Figure 5 As shown, the transformer 400 includes a base 410, a transformer body 420, and an isolation beam 430. The base 410 is used to support the transformer body 420. The isolation beam 430 is located on the side of the base 410 away from the transformer body 420. By setting the isolation beam 430, there is a certain gap between the transformer body 420 and the base 100. When water is accidentally accumulated on the base 100, the isolation beam 430 can isolate the transformer body 420 from the water, which helps to reduce the risk of water damage to the transformer body 420.

[0062] In some embodiments, the transformer body 420 adopts a three-dimensional wound core dry-type transformer structure, including a three-dimensional wound core 421, a coil 422, a clamping structure 423, and a lead wire 424. The clamping structure 423 is used to clamp the three-dimensional wound core 421, the coil 422 is wound on the three-dimensional wound core 421, and the lead wire 424 is used to introduce the voltage before transformation and to extract the voltage after transformation. These details will not be elaborated here.

[0063] The heat dissipation device 10 and transformer system of this application utilize the principle of heat pipes. When the transformer 400 is running, the heat generated by the transformer 400 is transferred to the inner shell 210 of the casing 200 through the air. Subsequently, the heat dissipation cavity 260, filled with cooling liquid and in a vacuum state, forms a heat pipe. After the inner shell 210 is heated, the heat pipe operates, and the cooling liquid in the heat dissipation cavity 260 evaporates to form steam, carrying away heat. The steam flows upward to the top of the heat dissipation cavity 260, where it condenses into liquid upon cooling. Simultaneously, it releases heat to the external environment through the outer shell 220. The liquid flows back into the tank under its own gravity, thus completing a closed loop, or a cooling and heat dissipation loop. This transfers the heat dissipated by the transformer 400 to the external environment outside the casing 200, achieving heat dissipation. The heat dissipation device 10 of this application forms a sealed cavity 250 for housing the transformer 400 between the casing 200 and the base 100, reducing the risk of water immersion damaging the transformer 400 in the external environment and facilitating waterproof protection of the transformer 400. Meanwhile, the heat pipe principle is used to dissipate heat from the sealed transformer 400, meeting the waterproof requirements of the transformer 400 while providing excellent heat dissipation. Furthermore, no other water-cooling or air-cooling structures are required, resulting in a simple structure that facilitates miniaturization.

[0064] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0065] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A heat dissipating device, characterized by, The heat dissipation device comprises: a base; and a cover arranged on the base, the cover comprising an inner cover and an outer cover, the inner cover and the base jointly defining a sealed cavity for accommodating a transformer; the outer cover being arranged outside the inner cover and jointly defining a heat dissipation cavity with the inner cover, the heat dissipation cavity being in a vacuum state and partially filled with a cooling liquid capable of being evaporated by heat.

2. The heat dissipating device according to claim 1, wherein The outer cover has an outer side surface arranged away from the inner cover, and a plurality of heat dissipation members are arranged on the outer side surface of the outer cover.

3. The heat dissipating device according to claim 2, wherein The outer cover comprises a side wall and a top wall arranged on the side wall, and the top wall and the base are respectively located at two ends of the side wall along a first direction; The plurality of heat dissipation members comprise a plurality of first heat dissipation members, and the plurality of first heat dissipation members are arranged at intervals along the first direction and are annularly arranged on the outer side surface of the side wall around an axis parallel to the first direction.

4. The heat dissipating device according to claim 3, wherein The plurality of heat dissipation members further comprise a plurality of second heat dissipation members, and the plurality of second heat dissipation members are arrayed on the top wall and located on the outer side surface of the top wall.

5. The heat dissipating device of claim 4, wherein The heat dissipation device further comprises a plurality of lifting members, and the plurality of lifting members are arranged on the top wall and located on a side of the top wall away from the base.

6. The heat dissipating device according to claim 5, wherein The plurality of lifting members are annularly arranged around the plurality of second heat dissipation members around an axis parallel to the first direction.

7. The heat dissipating device of claim 1, wherein A projection of the inner cover on a reference plane perpendicular to the first direction is circular, a projection of the outer cover on the reference plane is circular, and the projection of the outer cover on the reference plane covers the projection of the inner cover on the reference plane; The first direction is parallel to a direction in which the base points to a top of the cover.

8. The heat dissipating device of claim 1, wherein, At least one wire passing hole is arranged on the base in a direction in which the base points to the top of the cover, and the wire passing hole respectively communicates with the sealed cavity and an external environment.

9. The heat dissipating device of claim 1, wherein, The heat dissipation device further comprises a first fan arranged in the sealed cavity and located on the inner cover; and / or The heat dissipation device further comprises a second fan arranged in the sealed cavity and located on the transformer.

10. A pressure varying system characterized by, The heat dissipation device comprises a transformer and the heat dissipation device according to any one of claims 1-9, and the transformer is arranged in the heat dissipation device.

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