Aluminum case thin film capacitor

Abstract

The utility model relates to an aluminum shell film capacitor, include: casing, the cover plate of lid combination on the casing, the core body of accommodation in the casing, the casing and the core body between filling have insulating medium, still include: the fin between the core body outside wall and the casing inside wall, and the base between the core body bottom and the casing bottom wall, the fin and the base can cooperate to form the heat dissipation channel of erecting between the casing and the core body when the core body charges and discharges, the utility model discloses a fin and base cooperation forms the heat dissipation channel of " side wall and bottom", combines the material of good heat conductivity, can fast conduction the joule heat of core body charges and discharges to the casing and dissipates, the insulating medium filling part gap of filling at the same time, auxiliary heat even diffusion, avoid the core body medium ageing acceleration, capacity attenuation caused by internal heat accumulation, guarantee capacitor long -term stable work, also avoid the influence of high temperature to casing mechanical strength.

Description

Technical Field

[0001] This utility model belongs to the field of capacitor technology, and specifically relates to aluminum-cased film capacitors. Background Technology

[0002] As a core energy storage component in electronic circuits, capacitors are widely used in industrial control, new energy vehicles, power systems and other fields. Among them, aluminum-cased film capacitors have become an important choice for medium and high voltage scenarios due to their good temperature resistance and high capacitance stability.

[0003] However, aluminum-cased film capacitors rely heavily on the natural heat dissipation of the aluminum casing. The epoxy resin filling the space between the aluminum casing and the core has low thermal conductivity. The Joule heat generated during core operation tends to accumulate inside. Especially when the capacitor is used in high-power applications, the heat cannot be dissipated quickly, which will lead to accelerated aging of the dielectric inside the core, faster capacity decay, and in severe cases, even dielectric breakdown, thus shortening the overall lifespan of the capacitor. Utility Model Content

[0004] This utility model addresses the problems of existing technologies by providing an aluminum-cased film capacitor, the specific technical solution of which is as follows: Aluminum-cased film capacitors, including: case; A cover plate that fits over the casing; A core housed within a housing, wherein an insulating medium is filled between the housing and the core; Also includes: Fins disposed between the inner wall of the shell and the outer wall of the core; And a base set between the bottom of the core and the bottom wall of the shell; The fins and base can cooperate to form a heat dissipation channel between the shell and the core when the core is charged and discharged.

[0005] As a further technical solution of this utility model, the fins are evenly arranged in multiple sets around the core to center the core.

[0006] As a further technical solution of this utility model, a slot corresponding to the fin is provided on the inner sidewall of the housing, and the slot extends toward the opening end of the housing to form an open structure for the fin to slide in or out axially.

[0007] As a further technical solution of this utility model, the fins are provided with perforations along the thickness direction for the flow of insulating medium.

[0008] As a further technical solution of this utility model, a slot is provided in the middle of one end of the fin facing the core, and a V-shaped spring is provided in the slot. The V-shaped spring opens outward and deforms in the installed state to compensate for the compression of the core under vibration.

[0009] The beneficial effects of this utility model are as follows: The fins and base work together to form a heat dissipation channel on the sidewalls and bottom. Combined with a material with good thermal conductivity, the Joule heat generated by the charging and discharging of the core can be quickly conducted to the shell and dissipated. At the same time, the insulating medium filled in the gaps of the components helps to spread heat evenly, avoids the accelerated aging of the core medium and capacity decay caused by the accumulation of internal heat, ensures the long-term stable operation of the capacitor, and also avoids the impact of high temperature on the mechanical strength of the shell.

[0010] The fins are evenly distributed around the core in the circumference, which can form a uniform radial constraint on the core without the need for additional fixing structures, preventing the core from shifting inside the shell. This avoids electric field concentration caused by the core being too close to the shell in some areas, and ensures that the insulation medium between the core and the shell is of uniform thickness, reducing the risk of local breakdown and further improving the electrical safety of the capacitor. At the same time, it lays a structural foundation for the stable operation of the heat dissipation channel.

[0011] The open slots on the inner wall of the housing match the size of the fins, allowing the fins to slide axially into or out of the housing opening, greatly reducing assembly difficulty. At the same time, the slots limit the fins' movement during operation, ensuring that the fins always fit the housing and core, avoiding a decrease in heat dissipation efficiency due to fin displacement, reducing collision and wear between the fins and other components, extending the fins' service life, and reducing later maintenance costs.

[0012] The perforations on the fins can break the flow barrier of the medium, allowing the insulating medium to fill all the gaps between the shell and the core, avoiding local medium gaps; this ensures that the insulating medium is evenly distributed and forms a whole, improving insulation performance and preventing leakage or breakdown faults, and also helps to transfer heat through the uniform medium, further optimizing the heat dissipation effect.

[0013] During installation, the V-shaped spring in the fin slot fits the core through elastic deformation, forming a stable fixation. Under vibration environment, the V-shaped spring can absorb vibration energy by adjusting its deformation in real time, compensate for the displacement of the core, avoid hard collisions between the core and other components, prevent the core lead wires from falling off or the dielectric layer from breaking, and enable the capacitor to adapt to vibration scenarios such as automobiles and industrial equipment, thus broadening its application range. Attached Figure Description

[0014] Figure 1 A schematic diagram of the overall structure of an aluminum-cased film capacitor is shown. Figure 2 A schematic diagram of the internal structure of an aluminum-cased film capacitor is shown. Figure 3 A schematic diagram of the internal structure of the casing is shown; Figure 4 A schematic diagram of the fin structure is shown; Figure 5 A schematic diagram of the slot and V-shaped spring is shown.

[0015] Legend: 100. Shell; 110. Slot; 200. Cover plate; 300. Core; 400. Fin; 410. Perforation; 420. Groove; 430. V-shaped spring; 500. Base. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments.

[0017] Figures 1-4 The aluminum-cased film capacitor includes: Casing 100; A cover plate 200 that fits onto the housing 100; A core 300 is housed within a housing 100, and an insulating medium is filled between the housing 100 and the core 300. Fins 400 are disposed between the inner wall of the housing 100 and the outer wall of the core 300; And a base 500 disposed between the bottom of the core 300 and the bottom wall of the housing 100; The fins 400 and the base 500 can cooperate to form a heat dissipation channel between the housing 100 and the core 300 when the core 300 is charging and discharging.

[0018] The core 300 is the core component of the capacitor during charging and discharging, and it generates Joule heat due to current loss during operation. The cover plate 200, which closes onto the housing 100, provides a seal, preventing leakage of the insulating medium or the entry of external impurities. The housing 100, in turn, provides mechanical protection for the internal components. When the core 300 heats up, the heat is first transferred to the fins 400 and the base 500, which are in direct contact with it. The fins 400, which adhere to the inner wall of the housing 100, conduct the heat to the outer wall of the housing 100 and dissipate it. The base 500 transfers the heat from the bottom of the core 300 to the bottom wall of the housing 100. Together, these two components form a three-dimensional heat dissipation channel between the sidewalls and the bottom. Simultaneously, the encapsulated insulating medium fills the gaps between components, aiding in the even conduction of heat. This structure quickly dissipates the heat from the core 300, preventing heat buildup and excessively high temperatures. This slows down the aging of the internal dielectric of the core 300, reduces capacity decay, ensures the long-term stability of the capacitor, and prevents high temperatures from affecting the mechanical strength of the housing 100.

[0019] Multiple sets of fins 400 are evenly arranged around the core 300 to ensure the core 300 is centered.

[0020] When the fins 400 are evenly distributed around the core 300 in the circumference, each group of fins 400 will form supports from different radial directions of the core 300, generating a uniform radial constraint force on the core 300, limiting the radial displacement of the core 300 within the shell 100, and ensuring that the core 300 is always at the center position of the shell 100. This centering method does not require additional fixing structures and can be achieved through the distribution of the fins 400 themselves; it can avoid the core 300 shifting and causing local distances to be too close to the shell 100, preventing electric field concentration, while ensuring that the insulation dielectric thickness between the core 300 and the shell 100 is uniform, avoiding the risk of local breakdown caused by uneven dielectric thickness, further improving the electrical safety of the capacitor, and also providing a structural basis for the stable operation of the subsequent heat dissipation channel.

[0021] The inner wall of the housing 100 is provided with slots 110 corresponding to the fins 400, and the slots 110 extend toward the open end of the housing 100 to form an open structure for the fins 400 to slide into or out axially.

[0022] The dimensions of the slot 110 match the thickness of the fin 400. During assembly, the fin 400 can be inserted into the slot 110 from the open end of the housing 100. The slot 110 can precisely position the installation position of the fin 400, preventing offset or tilting during installation. The open structure allows the fin 400 to be assembled from the open end of the housing 100, reducing assembly difficulty, especially suitable for scenarios where the housing 100 is deep. At the same time, the slot 110 can limit the wobbling of the fin 400 during operation, ensuring that the fin 400 always fits against the inner wall of the housing 100 and the outer wall of the core 300, ensuring the continuity of the heat dissipation channel, preventing a decrease in heat dissipation efficiency due to fin 400 displacement, reducing collision and wear between the fin 400 and other components, and extending the service life of the fin 400.

[0023] The fin 400 has a perforation 410 along the thickness direction for the flow of insulating medium.

[0024] When filling the space between the housing 100 and the core 300 with insulating medium, the insulating medium flows due to gravity and filling pressure. The perforations 410 on the fins 400 break the obstruction of the medium flow by the fins 400, allowing the medium to flow freely through the perforations 410 on both sides of the fins 400, filling all gaps between the housing 100 and the core 300, including the contact surface gaps between the fins 400 and the core 300, and between the fins 400 and the housing 100. This design avoids localized medium gaps caused by the fins 400 blocking the medium, ensuring uniform distribution of the insulating medium and forming a whole, improving overall insulation performance, and preventing leakage or breakdown caused by localized absence of medium. At the same time, the uniformly distributed insulating medium helps the fins 400 transfer heat, allowing the heat from the core 300 to be more evenly diffused to the fins 400 and the housing 100, further optimizing the heat dissipation effect.

[0025] The fin 400 has a slot 420 in the middle of the end facing the core 300, and a V-shaped spring 430 is provided in the slot 420. The V-shaped spring 430 opens outward and deforms in the installed state to compensate for the compression of the core 300 under vibration.

[0026] During installation, the core 300 compresses the V-shaped spring 430, causing the V-shaped spring 430 to open outward from its initial V-shaped structure and undergo elastic deformation. The reaction force generated by the deformation will tightly adhere to the surface of the core 300, stabilizing and fixing the core 300. When the capacitor is in a vibrating environment, the core 300 will tend to displace due to vibration. At this time, the V-shaped spring 430 can absorb vibration energy through its own elastic deformation and adjust the degree of deformation in real time to compensate for the displacement of the core 300, avoiding hard collisions between the core 300 and the fins 400 or the shell 100. This reduces the damage of vibration to the internal structure of the core 300, prevents the core 300 leads from falling off or the dielectric layer from cracking, ensures the normal operation of the capacitor in a vibrating environment, and broadens its applicable scenarios.

[0027] Both the fins 400 and the base 500 are made of insulating materials with good thermal conductivity, such as ceramics (alumina ceramics, aluminum nitride ceramics, silicon nitride ceramics), modified plastics, etc.

[0028] The fins 400 and base 500 must simultaneously meet the requirements of "thermal conductivity" and "insulation." Materials with good thermal conductivity can quickly receive the heat transferred from the core 300 and efficiently conduct it to the shell 100, ensuring the thermal conductivity of the heat dissipation channel. Insulating materials prevent the fins 400 and base 500 from becoming conductive pathways between the core 300 and the shell 100, preventing leakage or short circuits. In particular, they can isolate the high voltage of the core 300 during operation, protecting the safety of personnel and equipment outside the shell 100. This choice of materials that combine thermal conductivity and insulation solves the heat dissipation problem of the core 300 while ensuring the electrical safety of the capacitor, avoiding heat dissipation failure or electrical malfunctions due to insufficient material properties. Furthermore, these materials typically have good temperature resistance, adapting to temperature changes during the operation of the core 300 and extending the service life of the fins 400 and base 500.

[0029] The above embodiments are only used to illustrate the technical solution of this utility model, and are not intended to limit it.

Claims

1. Aluminum-cased film capacitors, including: Casing (100); A cover plate (200) that fits onto the housing (100); A core (300) is housed within a housing (100), and an insulating medium is filled between the housing (100) and the core (300); Its characteristic is that it further includes: Fins (400) are disposed between the inner wall of the shell (100) and the outer wall of the core (300). And a base (500) disposed between the bottom of the core (300) and the bottom wall of the housing (100); The fins (400) and the base (500) can cooperate to form a heat dissipation channel between the shell (100) and the core (300) when the core (300) is charged and discharged.

2. The aluminum-cased film capacitor according to claim 1, characterized in that: The fins (400) are evenly arranged in multiple sets around the core (300) to center the core (300).

3. The aluminum-cased film capacitor according to claim 2, characterized in that: The inner wall of the housing (100) is provided with a slot (110) corresponding to the fin (400), and the slot (110) extends toward the opening end of the housing (100) to form an open structure for the fin (400) to slide into or out axially.

4. The aluminum-cased film capacitor according to claim 3, characterized in that: The fin (400) has a perforation (410) along the thickness direction for the flow of insulating medium.

5. The aluminum-cased film capacitor according to claim 3, characterized in that: The fin (400) has a slot (420) in the middle of one end facing the core (300), and a V-shaped spring (430) is provided in the slot (420). The V-shaped spring (430) opens outward and deforms in the installed state to compensate for the compression of the core (300) under vibration.

Images