Explosion-proof reliable alternating current filter capacitor with low temperature rise

Abstract

The invention belongs to the technical field of capacitors, and particularly relates to a low-temperature-rise explosion-proof reliable alternating current filter capacitor which comprises a flanged aluminum shell, the top of the flanged aluminum shell is connected with an alternating current aluminum cover, and the inner wall of the flanged aluminum shell is provided with a core group. The inner wall of the flanged aluminum shell is also provided with a positioning sleeve group for fixing the core group so as to increase the creepage distance; and an insulating material is filled between the outer surface of the core group and the inner wall of the flanged aluminum shell so as to isolate the core group from the flanged aluminum shell to play an insulating role. According to the invention, the metallized film of the core group adopts a physical vapor deposition pattern evaporation and wave slitting technology, different pattern evaporation is designed according to a simulation current path and a heating condition, the self-healing capability is enhanced, and the insulating strength is improved; the edge contact area is increased, the current impact resistance is improved, the ESR value of the capacitor is reduced, and the heating power of the capacitor is reduced.

Description

Technical Field

[0001] This invention belongs to the field of capacitor technology, specifically relating to a low-temperature-rise, explosion-proof, and reliable AC filter capacitor. Background Technology

[0002] An AC filter capacitor is a type of capacitor specifically designed for use in AC circuits. Through its electrical characteristics of "passing AC while blocking DC, and passing high frequencies while blocking low frequencies," it filters out harmful harmonics and noise in the circuit, suppresses voltage and current distortion, and improves power quality. It is an indispensable passive filtering component in power electronic systems and industrial electrical equipment, its core function being to ensure stable circuit operation, reduce equipment losses, and minimize electromagnetic interference.

[0003] Harmonic currents often exist in AC circuits due to nonlinear loads such as rectifiers and frequency converters. These harmonics can cause voltage waveform distortion, equipment heating, and increased energy consumption. AC filter capacitors and inductors are combined to form filter circuits (such as LC filter circuits and LC series-parallel resonant filter circuits). These circuits exhibit low impedance characteristics for harmonics of specific frequencies, short-circuiting the harmonic current to ground or confining it within the filter circuit, allowing only the fundamental frequency current (such as 50Hz / 60Hz) to pass normally.

[0004] Existing AC filter capacitors have the following problems in practical use:

[0005] 1. Existing AC capacitors used in high-frequency filtering new energy storage systems experience severe overheating during long-term operation under load. Poor internal conduction and heat dissipation lead to heat accumulation inside the capacitor, causing the temperature to rise. This results in easy aging of the thin-film dielectric, a decrease in insulation performance, and ultimately premature breakdown failure of the capacitor.

[0006] 2. The existing AC capacitor has poor explosion-proof performance. The explosion-proof device cannot act in time when there is an internal fault in the capacitor, and continuous operation under load may cause fire or explosion accidents. Or, due to excessive sensitivity of the explosion-proof device, it may disconnect prematurely during transportation, vibration and operation under normal working conditions, which will bring unnecessary trouble to engineering maintenance and replacement.

[0007] 3. Most existing AC capacitors are fully sealed, making it difficult to monitor the amount of potting compound used during manufacturing. Too much will cause thermal expansion of the product; too little will lead to localized overheating and uneven heat conduction, both of which will affect product performance.

[0008] 4. The existing AC capacitor has a large internal resistance and loss tangent, can withstand a small ripple current, and has a short lifespan, which cannot meet the quality assurance requirements of new energy storage device systems.

[0009] In view of this, the present invention provides an AC filter capacitor with low temperature rise, explosion-proof and reliable performance to solve the above problems. Summary of the Invention

[0010] To achieve the above objectives, the present invention provides the following technical solution: a low-temperature-rise, explosion-proof, and reliable AC filter capacitor, comprising a flanged aluminum shell, an AC aluminum cover connected to the top of the flanged aluminum shell, a core assembly provided on the inner wall of the flanged aluminum shell, a positioning sleeve for fixing the core assembly to increase the creepage distance, and an insulating material filling the space between the outer surface of the core assembly and the inner wall of the flanged aluminum shell to insulate and isolate the core assembly from the flanged aluminum shell.

[0011] As a preferred embodiment of the present invention, which is a low-temperature-rise, explosion-proof, and reliable AC filter capacitor, the flanged aluminum shell is cylindrical and used to load the capacitor core assembly, with its open end sealed by the AC aluminum cap.

[0012] As a preferred embodiment of the low-temperature-rise, explosion-proof, and reliable AC filter capacitor of the present invention, the core group comprises three cores, and the three cores of the core group are connected together in series and parallel by lead-out copper wires.

[0013] As a preferred embodiment of the low temperature rise, explosion-proof, and reliable AC filter capacitor of the present invention, the three cores of the core assembly are respectively filled with potting material, and the potting material wraps the core assembly to fix the internal components to enhance the insulation performance between the lines.

[0014] As a preferred embodiment of the present invention, the AC aluminum cover includes an aluminum cover piece connected to the top of the flanged aluminum shell, an explosion-proof block connected to the opening of the flanged aluminum shell and located directly below the aluminum cover piece, a lead wire connected through the surface of the explosion-proof block, and a terminal block mounted on the upper surface of the aluminum cover piece.

[0015] As a preferred embodiment of the low-temperature-rise, explosion-proof, and reliable AC filter capacitor of the present invention, the surface of the explosion-proof block is further provided with filling holes for filling, and the filling holes are arranged in four groups in a circular array with the center line of the explosion-proof block as the center.

[0016] As a preferred embodiment of the present invention, the aluminum cover includes a cover plate connected to the top of the flanged aluminum shell, and a reinforcing rib 4mm inside the rolled edge of the cover plate, with a depth of about 1.5mm. The reinforcing rib adopts a split stepped structure.

[0017] As a preferred embodiment of the low-temperature-rise, explosion-proof, and reliable AC filter capacitor of the present invention, the core of the core assembly is made of a metallized thin film wound together. The metallized thin film is produced by a wave-cutting process and a special patterned coating is deposited to reduce the internal resistance and heat generation of the core.

[0018] As a preferred embodiment of the low temperature rise, explosion-proof, and reliable AC filter capacitor of the present invention, the positioning sleeve includes a bottom positioning sleeve fitted at the bottom end of the core assembly and disposed on the bottom side of the inner wall of the flanged aluminum shell, and a top positioning sleeve fitted at the top end of the core assembly and disposed on the inner wall of the flanged aluminum shell.

[0019] As a preferred embodiment of the present invention, which is a low-temperature-rise, explosion-proof, and reliable AC filter capacitor, a large-diameter mandrel is passed through the interior of a single core of the core assembly, and a metallized thin film is wound around the core assembly as the axis to form a single core of the core assembly.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] In this invention, the metallization film of the core is deposited using physical vapor deposition patterning and wave slicing technology. Different pattern deposition is designed according to the simulated current path and heat generation, which enhances self-healing ability, improves insulation strength, increases edge contact area, improves resistance to current surges, reduces capacitor ESR value, and reduces capacitor heat generation power.

[0022] The outer ring of the cover plate is designed with a reinforcing rib. When a fault occurs inside the capacitor, the connection between the explosion-proof block and the cover plate will bulge and deform, which can effectively break the circuit in time. This prevents the outer ring of the cover plate from bulging while the deformation at the connection line in the middle of the cover plate and the explosion-proof block is not obvious. The faulty product cannot be in an open circuit state, and the explosion-proof will fail. The riveted electrode under the explosion-proof block is re-soldered to prevent the explosion-proof from being too sensitive and opening the circuit when the capacitor is transported and vibrated.

[0023] The capacitor uses a split AC aluminum cover. The explosion-proof block and the cover plate can be assembled. After the core is assembled into the flanged aluminum shell, it is first filled through the filling hole. The amount of potting material can be observed by the naked eye through the filling hole of the explosion-proof block. After it is appropriate, the cover plate is assembled.

[0024] Increasing the inner and outer diameters of the metallized thin film winding mandrel in the core assembly enhances internal heat conduction and dissipation capabilities, reduces internal temperature rise, and improves the product's electrical performance. Attached Figure Description

[0025] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0026] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0027] Figure 2 This is a cross-sectional view of the internal structure of the flanged aluminum shell of the present invention;

[0028] Figure 3 This is a schematic diagram of the connection structure between the core assembly and the lead-out copper wires of the present invention;

[0029] Figure 4 This is a cross-sectional structural diagram of the present invention;

[0030] Figure 5 This is a schematic diagram of the infusion structure of the present invention;

[0031] Figure 6 This invention relates to a split-type stepped reinforced explosion-proof AC aluminum cover.

[0032] Figure 7 This is a structural diagram of the large-diameter mandrel of the present invention;

[0033] Figure 8 This is a thin film diagram of the special pattern evaporation and wave slitting process of the present invention.

[0034] In the diagram: 1. Flanged aluminum shell; 2. AC aluminum cover; 21. Aluminum cover part; 211. Cover plate; 212. Reinforcing rib; 22. Explosion-proof block; 23. Lead wire; 24. Terminal block; 25. Filling hole; 3. Positioning sleeve assembly; 31. Bottom positioning sleeve; 32. Top positioning sleeve; 4. Core assembly; 5. Lead copper wire; 6. Encapsulating material; 7. Insulating material; 8. Large-diameter mandrel. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] This invention relates to a low-temperature-rise, explosion-proof, and reliable AC filter capacitor, such as... Figures 1-8 As shown, it includes a flanged aluminum shell 1, an AC aluminum cover 2 connected to the top of the flanged aluminum shell 1, a core assembly 4 provided on the inner wall of the flanged aluminum shell 1, and a positioning sleeve 3 for fixing the core assembly 4 to increase the creepage distance. An insulating material 7 is filled between the outer surface of the core assembly 4 and the inner wall of the flanged aluminum shell 1 to isolate the core assembly from the flanged aluminum shell 1 and provide insulation.

[0037] The flanged aluminum shell 1 is cylindrical and is used to house the capacitor core assembly 4. It works in conjunction with the AC aluminum cover 2 to provide a sealing function.

[0038] Furthermore, the core assembly 4 includes three cores, which are connected together in series and parallel by lead-out copper wires 5.

[0039] Furthermore, the three cores of the core assembly 4 are respectively filled with potting compound 6, which wraps the core assembly 4 to fix the internal components and enhance the insulation performance between the lines.

[0040] Furthermore, the AC aluminum cover 2 includes an aluminum cover 21 connected to the top of the flanged aluminum housing 1, an explosion-proof block 22 connected to the opening of the flanged aluminum housing 1 and located directly below the aluminum cover 21, a lead wire 23 passing through and connected to the surface of the explosion-proof block 22, and a terminal block 24 mounted on the upper surface of the aluminum cover 21.

[0041] Furthermore, the surface of the explosion-proof block 22 is also provided with injection holes 25 for filling. The injection holes 25 are arranged in four groups in a ring array with the center line of the explosion-proof block 22 as the center. A split aluminum cover 21 is adopted, and the explosion-proof block 22 and the aluminum cover 21 can be assembled. After the core assembly 4 is installed into the flanged aluminum shell 1, it is filled through the injection holes 25. The amount of potting material 6 can be observed visually through the injection holes 25 of the explosion-proof block 22.

[0042] Furthermore, the aluminum cover 21 includes a cover plate 211 connected to the top of the flanged aluminum shell 1, and a reinforcing rib 212 located 4mm inside the rolled edge of the cover plate 211. The depth of the reinforcing rib 212 is approximately 1.5mm, and the reinforcing rib 212 adopts a split stepped structure. By setting a reinforcing rib 212 inside the cover plate 211, when a fault occurs inside the capacitor, the connection between the explosion-proof block 22 and the cover plate 211 will bulge and deform, effectively breaking the circuit in a timely manner.

[0043] Furthermore, the core of core assembly 4 is made of a metallized thin film wound together. This metallized thin film is produced using a wave-cutting process, with a special patterned deposition coating to reduce internal resistance and heat generation within the core. The metallized thin film of core assembly 4 employs PVD physical vapor deposition pattern deposition and wave-cutting technology, allowing for the design of different patterned deposition coatings based on simulated current paths and heat generation conditions. This enhances self-healing capabilities and insulation strength; it also increases edge contact area to improve resistance to current surges, while simultaneously reducing the capacitor's ESR value and heating power.

[0044] Furthermore, the positioning sleeve 3 includes a bottom positioning sleeve 31 that is fitted at the bottom end of the core assembly 4 and disposed on the bottom side of the inner wall of the flanged aluminum shell 1, and a top positioning sleeve 32 that is fitted at the top end of the core assembly 4 and disposed on the inner wall of the flanged aluminum shell 1.

[0045] Furthermore, a large-diameter mandrel 8 runs through the interior of each core of the core assembly 4, and the metallized film is wound around the core assembly 4 to form a single core of the core assembly 4. By increasing the diameter of the metallized film wound around the large-diameter mandrel 8 inside and outside the core assembly 4, the internal heat conduction and heat dissipation capacity of the core assembly 4 is enhanced, and the internal temperature rise of the product is reduced.

[0046] In use, the metallization film of core 4 adopts PVD physical vapor deposition pattern evaporation and wave cutting technology. Different pattern evaporation is designed according to the simulated current path and heat generation to enhance self-healing ability, improve insulation strength, enhance edge contact area, improve current surge resistance, reduce capacitor ESR value, and reduce capacitor heat generation power.

[0047] The outer ring of the cover plate 211 is designed with a reinforcing rib 212. When a fault occurs inside the capacitor, the connection between the explosion-proof block 22 and the cover plate 211 will bulge and deform, which can effectively break the circuit in time. This prevents only the outer ring of the cover plate 211 from bulging, while the deformation at the connection line in the middle of the cover plate 211 and the explosion-proof block 22 is not obvious. The faulty product cannot be in an open circuit state, and the explosion-proof will fail. The riveted electrode under the explosion-proof block 22 is re-soldered to prevent the explosion-proof from being too sensitive and opening the circuit when the capacitor is transported and vibrated.

[0048] The capacitor uses a split AC aluminum cover 2, and the explosion-proof block 22 and cover plate 211 can be assembled. After the core group 4 is installed into the flanged aluminum shell 1, it is first filled through the filling hole 25. The amount of potting material can be observed by the naked eye through the filling hole 25 of the explosion-proof block 22. After it is appropriate, the cover plate 211 is assembled.

[0049] Increasing the inner and outer diameters of the metallized thin film winding mandrel in core group 4 enhances internal heat conduction and dissipation capabilities, reduces internal temperature rise, and improves the electrical performance of the product.

[0050] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A low-temperature-rise, explosion-proof, and reliable AC filter capacitor, comprising a flanged aluminum casing (1), characterized in that: The top of the flanged aluminum shell (1) is connected to an AC aluminum cover (2). The inner wall of the flanged aluminum shell (1) is provided with a core assembly (4). The inner wall of the flanged aluminum shell (1) is also provided with a positioning sleeve (3) for fixing the core assembly (4) to increase the creepage distance. The outer surface of the core assembly (4) and the inner wall of the flanged aluminum shell (1) are filled with insulating material (7) to insulate and isolate the core assembly from the flanged aluminum shell (1).

2. The low-temperature-rise, explosion-proof, and reliable AC filter capacitor according to claim 1, characterized in that: The flanged aluminum shell (1) is cylindrical and is used to load the capacitor core assembly (4), with its open end sealed by the AC aluminum cover (2).

3. The low-temperature-rise, explosion-proof, and reliable AC filter capacitor according to claim 1, characterized in that: The core assembly (4) includes three cores, and the three cores of the core assembly (4) are connected together in series and parallel by lead-out copper wires (5).

4. The low-temperature-rise, explosion-proof, and reliable AC filter capacitor according to claim 3, characterized in that: The three cores of the core assembly (4) are respectively filled with potting compound (6), which wraps the core assembly (4) to fix the internal components and enhance the insulation performance between the lines.

5. The low-temperature-rise, explosion-proof, and reliable AC filter capacitor according to claim 1, characterized in that: The AC aluminum cover (2) includes an aluminum cover piece (21) connected to the top of the flanged aluminum shell (1), an explosion-proof block (22) connected to the opening of the flanged aluminum shell (1) and located directly below the aluminum cover piece (21), a lead wire (23) that passes through and is connected to the surface of the explosion-proof block (22), and a terminal block (24) installed on the upper surface of the aluminum cover piece (21).

6. The low-temperature-rise, explosion-proof, and reliable AC filter capacitor according to claim 5, characterized in that: The surface of the explosion-proof block (22) is also provided with injection holes (25) for injection. The injection holes (25) are arranged in four groups in a ring array with the center line of the explosion-proof block (22) as the center.

7. The low-temperature-rise, explosion-proof, and reliable AC filter capacitor according to claim 6, characterized in that: The aluminum cover (21) includes a cover plate (211) connected to the top of the flanged aluminum shell (1), and a reinforcing rib (212) located 4 mm inside the rolled edge of the cover plate (211), with a depth of about 1.5 mm. The reinforcing rib (212) adopts a split stepped structure.

8. The low-temperature-rise, explosion-proof, and reliable AC filter capacitor according to claim 1, characterized in that: The core of the core assembly (4) is made of a metallized thin film. The metallized thin film is made by wave cutting process and special pattern evaporation to reduce the internal resistance and heat generation of the core.

9. The low-temperature-rise, explosion-proof, and reliable AC filter capacitor according to claim 8, characterized in that: The positioning sleeve (3) includes a bottom positioning sleeve (31) fitted at the bottom of the core group (4) and located on the bottom side of the inner wall of the flanged aluminum shell (1), and a top positioning sleeve (32) fitted at the top of the core group (4) and located on the inner wall of the flanged aluminum shell (1).

10. The low-temperature-rise, explosion-proof, and reliable AC filter capacitor according to claim 1, characterized in that: The core of the core group (4) has a large-diameter mandrel (8) running through its interior. The metallized film is wound around the core group (4) as the axis to form a single core of the core group (4).

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