A thin-film capacitor for reducing partial discharge in the electrode casing and its filling method.

Abstract

This invention discloses a thin-film capacitor and its filling method for reducing partial discharge of the electrode shell, comprising: a capacitor shell and a shell reinforcement mechanism disposed therein; the shell reinforcement mechanism includes: a main reinforcing rib and two auxiliary reinforcing ribs, the two auxiliary reinforcing ribs being located on both sides of the main reinforcing rib, the two sides of the main reinforcing rib being connected to the inner side of the capacitor shell, and a bottom baffle disposed inside the capacitor shell; a capacitor core is disposed in the space formed by the inner side of the capacitor shell and the top of the bottom baffle, and an exhaust pipe is disposed inside the auxiliary reinforcing rib, the exhaust pipe penetrating the interior of the auxiliary reinforcing rib and the bottom baffle and extending to the bottom end of the capacitor shell, and a central exhaust mesh is disposed in the through groove of the bottom baffle; this method helps to expel air from the upper part of the capacitor shell during the filling of sealant, which can accelerate the filling of the capacitor, and also reduces the generation of air bubbles, thereby reducing the probability of partial discharge of the electrode shell.

Description

Technical Field

[0001] This invention relates to the field of thin-film capacitor technology, and more specifically to a thin-film capacitor that reduces partial discharge in the electrode case and its potting method. Background Technology

[0002] With the rapid development of the power electronics industry, the demand for power electronic capacitors is increasing in fields such as rail transportation, SVG, and solar photovoltaics. As a key component in power devices, capacitors play a crucial role in the reliability of the entire system. As an indispensable component, the energy storage capacity and size of power electronic capacitors increase with the power of the overall module. Due to the increased size, film capacitors are more prone to problems such as the shell separating from the internal resin and increased filling air bubbles, leading to increased partial discharge between the electrodes. Summary of the Invention

[0003] The purpose of this invention is to provide a thin-film capacitor and its filling method for reducing partial discharge in the electrode shell, thereby solving the following technical problems:

[0004] Existing large-sized film capacitors are prone to problems such as the shell separating from the internal resin and an increase in filling air bubbles, resulting in increased partial discharge between the electrode and the shell.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A thin-film capacitor for reducing partial discharge in the electrode shell includes: a capacitor shell and a shell reinforcement mechanism disposed inside it;

[0007] The shell reinforcement mechanism includes a main reinforcing rib and two auxiliary reinforcing ribs, the two auxiliary reinforcing ribs being located on both sides of the main reinforcing rib, the two sides of the main reinforcing rib being connected to the inner side of the capacitor shell, and a bottom baffle being provided inside the capacitor shell.

[0008] The capacitor core is disposed in the space formed by the inner side of the capacitor shell and the top of the bottom baffle. An exhaust pipe is disposed inside the auxiliary reinforcing rib. The exhaust pipe passes through the interior of the auxiliary reinforcing rib and the bottom baffle and extends to the bottom end of the capacitor shell. A central exhaust mesh is disposed in the through groove of the bottom baffle.

[0009] The central exhaust mesh is located below the main reinforcing rib.

[0010] Furthermore, an exhaust pipe is provided at the bottom of the capacitor housing, and a sliding plate is slidably connected inside the exhaust pipe. Several upper exhaust channels are penetrating inside the sliding plate.

[0011] Furthermore, an air-blocking block is provided at the bottom of the sliding plate, and a bottom exhaust groove is provided at the bottom of the capacitor housing corresponding to the air-blocking block.

[0012] Furthermore, movable baffles are provided on both sides of the exhaust pipe, and the middle part of the movable baffle is installed to the inside of the baffle mounting bracket via a rotating shaft. The baffle mounting bracket is located at the bottom inside the capacitor housing.

[0013] Furthermore, one side of the movable baffle abuts against the side of the exhaust pipe.

[0014] Furthermore, a bottom reinforcing shell is provided at the bottom end of the capacitor housing.

[0015] Furthermore, an electrode assembly is provided at the top of the capacitor housing, and the electrode assembly is electrically connected to the capacitor core.

[0016] Furthermore, a sealant injection port is provided at the top of the capacitor housing.

[0017] Furthermore, the capacitor core is provided in a plurality of forms, which are arranged in an array inside the capacitor housing.

[0018] Furthermore, the exhaust pipe is located below the central exhaust net at the corresponding position, and side exhaust holes are provided on both sides of the exhaust pipe. The distance between the top of the side exhaust hole and the bottom surface of the capacitor housing is less than the distance between the pivot position of the movable baffle and the bottom surface of the capacitor housing.

[0019] A method for filling a thin-film capacitor to reduce partial discharge in the electrode shell includes the following steps:

[0020] S1: Capacitor: Before filling, remove the bottom reinforcing shell at the bottom of the capacitor casing;

[0021] S2: Fill the inside of the capacitor casing with sealant through the sealant injection port;

[0022] S3: When the sealant is injected, the air inside the capacitor shell is discharged through the middle exhaust net on the bottom baffle into the space enclosed by the bottom end of the capacitor shell and the bottom baffle, and is discharged from the bottom exhaust groove through the upper exhaust groove and the side exhaust hole. The air above the capacitor shell is discharged through the exhaust pipe.

[0023] S4: During the injection of sealant, the sealant will block the upper vent groove and the side vent hole. The sealant will extend beyond the top of the auxiliary reinforcing rib and be discharged through the vent pipe.

[0024] S5: When the sealant is discharged from the exhaust pipe, install the bottom reinforcing housing onto the bottom of the capacitor housing.

[0025] The beneficial effects of this invention are:

[0026] This invention enables the sealant to quickly fill the gap between the capacitor shell and the capacitor core during sealant injection. Air inside the capacitor shell is discharged through a central exhaust mesh on the bottom baffle into the space enclosed by the bottom end of the capacitor shell and the bottom baffle. The air then passes through the upper exhaust groove and side exhaust holes, and finally exits through the bottom exhaust groove. This facilitates the removal of air from inside the capacitor shell during sealant injection, reducing the formation of air bubbles and allowing the sealant to fill the capacitor shell quickly. Simultaneously, air above the capacitor shell can enter the exhaust pipe of the auxiliary reinforcing rib and exit from inside the capacitor shell through the exhaust pipe. This helps to remove air from the upper part of the capacitor shell during sealant injection, accelerating the injection process and reducing the formation of air bubbles, thus lowering the probability of partial discharge on the capacitor casing. Attached Figure Description

[0027] The invention will now be further described with reference to the accompanying drawings.

[0028] Figure 1 This is a schematic diagram of the structure of the present invention;

[0029] Figure 2 This is an enlarged view of region A of the present invention;

[0030] Figure 3 This is a schematic diagram of the exhaust pipe and movable baffle of the present invention;

[0031] Figure 4 This is a top view of the invention from the BB direction;

[0032] Figure 5 This is a cross-sectional view of the present invention in the CC direction.

[0033] In the diagram: 1. Capacitor core; 2. Capacitor housing; 3. Electrode assembly; 4. Main reinforcing rib; 5. Auxiliary reinforcing rib; 6. Sealant injection port; 7. Bottom baffle; 8. Bottom reinforced housing; 9. Exhaust pipe; 10. Exhaust stack; 11. Sliding plate; 12. Middle exhaust mesh; 13. Movable baffle; 14. Baffle mounting bracket; 15. Air blocking block; 16. Upper exhaust channel; 17. Side exhaust hole; 18. Bottom exhaust channel. Detailed Implementation

[0034] 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.

[0035] Please see Figure 1-5 As shown, the present invention is a thin-film capacitor for reducing partial discharge of the electrode shell, comprising: a capacitor shell 2 and a shell reinforcement mechanism disposed therein;

[0036] The shell reinforcement mechanism includes: a main reinforcing rib 4 and two auxiliary reinforcing ribs 5, the two auxiliary reinforcing ribs 5 being located on both sides of the main reinforcing rib 4, the two sides of the main reinforcing rib 4 being connected to the inner side of the capacitor shell 2, and a bottom baffle 7 being provided inside the capacitor shell 2.

[0037] Specifically, the space formed by the bottom of the capacitor housing 2 and the bottom baffle 7 facilitates the storage of air discharged during the filling of the capacitor housing 2; at the same time, the two large surfaces of the capacitor housing 2 are fixed by the main reinforcing rib 4 and the auxiliary reinforcing rib 5 to prevent the two large surfaces of the capacitor housing 2 from bulging and deforming.

[0038] The capacitor core 1 is provided in the space formed by the inner side of the capacitor housing 2 and the top of the bottom baffle 7. The exhaust pipe 9 is provided inside the auxiliary reinforcing rib 5. The exhaust pipe 9 passes through the interior of the auxiliary reinforcing rib 5 and the bottom baffle 7 and extends to the bottom end of the capacitor housing 2. The central exhaust net 12 is provided in the through groove of the bottom baffle 7.

[0039] The central exhaust mesh 12 is located below the main reinforcing rib 4.

[0040] Specifically, during the encapsulation process, the sealant quickly fills the gap between the capacitor housing 2 and the capacitor core 1. Air inside the capacitor housing 2 is discharged through the central exhaust mesh 12 on the bottom baffle 7 into the space enclosed by the bottom end of the capacitor housing 2 and the bottom baffle 7, and finally exits through the upper exhaust groove 16 and the side exhaust hole 17, and through the bottom exhaust groove 18. This facilitates the removal of air from inside the capacitor housing 2 during sealant encapsulation, helps reduce the generation of air bubbles inside the capacitor housing 2 during sealant encapsulation, and allows the sealant to quickly fill the interior of the capacitor housing 2. Simultaneously, air above the capacitor housing 2 can enter the exhaust pipe 9 of the auxiliary reinforcing rib 5 and exit from inside the capacitor housing 2 through the exhaust pipe 9. This helps to remove air from the upper part of the capacitor housing 2 during sealant encapsulation, which can accelerate the encapsulation of the capacitor, reduce the generation of air bubbles, and lower the probability of partial discharge of the electrode shell.

[0041] In one embodiment of the present invention, an exhaust pipe 10 is provided at the bottom of the inner side of the capacitor housing 2, and a sliding plate 11 is slidably connected inside the exhaust pipe 10. Several upper exhaust channels 16 are passed through the interior of the sliding plate 11.

[0042] In one embodiment of the present invention, a blockage block 15 is provided at the bottom end of the sliding plate 11, and a bottom exhaust channel 18 is provided at the bottom end of the capacitor housing 2 at a position corresponding to the blockage block 15. Specifically, the air inside the capacitor housing 2 is discharged through the central exhaust net 12 on the bottom baffle 7 into the space enclosed by the bottom end of the capacitor housing 2 and the bottom baffle 7, and finally passes through the upper exhaust channel 16 and the side exhaust hole 17, and is discharged through the bottom exhaust channel 18.

[0043] In one embodiment of the present invention, movable baffles 13 are provided on both sides of the exhaust pipe 10. The middle part of the movable baffle 13 is mounted to the inside of the baffle mounting bracket 14 via a rotating shaft. The baffle mounting bracket 14 is located at the bottom inside the capacitor housing 2.

[0044] In one embodiment of the invention, one side of the movable baffle 13 abuts against the side of the exhaust pipe 10. Specifically, as the amount of sealant injected into the capacitor housing 2 increases, the sealant gradually passes through the central exhaust mesh 12 under its own weight and accumulates on the sliding plate 11. The weight of the sealant on the sliding plate 11 increases, pushing the sliding plate 11 downward. At the same time, excess sealant overflows from the edge of the exhaust pipe 10 to one side of the movable baffle 13, causing the movable baffle 13 to tilt towards the exhaust pipe 10. Figure 3 As shown, the sealant flows down the exhaust pipe 10 to the side exhaust hole 17, gradually sealing the side exhaust hole 17. At the same time, the sliding plate 11 descends further, and the air-blocking block 15 at the bottom of the sliding plate 11 seals the bottom exhaust channel 18, so that the bottom exhaust channel 18 of the capacitor housing 2 is closed. At this time, the air above the capacitor housing 2 can still enter the exhaust pipe 9 of the auxiliary reinforcing rib 5 and be discharged from the inside of the capacitor housing 2 through the exhaust pipe 9.

[0045] In one embodiment of the present invention, a bottom reinforcing housing 8 is provided at the bottom end of the capacitor housing 2.

[0046] In one embodiment of the present invention, an electrode assembly 3 is provided at the top of the capacitor housing 2, the electrode assembly 3 is electrically connected to the capacitor core 1, and a sealant injection port 6 is provided at the top of the capacitor housing 2.

[0047] In one embodiment of the present invention, a plurality of capacitor cores 1 are provided, and the plurality of capacitor cores 1 are distributed in an array inside the capacitor housing 2.

[0048] In one embodiment of the present invention, the exhaust pipe 10 is located below the central exhaust net 12. Side exhaust holes 17 are provided on both sides of the exhaust pipe 10. The distance between the top of the side exhaust hole 17 and the bottom surface of the capacitor housing 2 is less than the distance between the pivot position of the movable baffle 13 and the bottom surface of the capacitor housing 2. The movable baffle 13 can prevent a small amount of sealant from blocking the side exhaust holes 17. Only when the sealant can push the movable baffle 13 to rotate to one side can the sealant block the side exhaust holes 17.

[0049] Another embodiment of the present invention: a method for filling a thin-film capacitor to reduce partial discharge of the electrode shell, comprising the following steps:

[0050] S1: Capacitor: Before filling, remove the bottom reinforcing shell 8 at the bottom of the capacitor shell 2;

[0051] S2: Fill the inside of the capacitor housing 2 with sealant through the sealant injection port 6;

[0052] S3: When the sealant is injected, the air inside the capacitor housing 2 is discharged through the middle exhaust net 12 on the bottom baffle 7 into the space enclosed by the bottom end of the capacitor housing 2 and the bottom baffle 7, and is discharged from the bottom exhaust groove 18 through the upper exhaust groove 16 and the side exhaust hole 17. The air above the capacitor housing 2 is discharged through the exhaust pipe 9.

[0053] S4: During the injection of sealant, the sealant will block the upper vent groove 16 and the side vent hole 17. The sealant will extend beyond the top of the auxiliary reinforcing rib 5 and be discharged through the vent pipe 9.

[0054] S5: When the sealant is discharged from the exhaust pipe 9, the bottom reinforcing housing 8 is installed to the bottom of the capacitor housing 2.

[0055] The specific workflow of this invention is as follows: Before filling the capacitor, the bottom reinforcing shell 8 at the bottom end of the capacitor shell 2 is removed, and sealant is filled into the inside of the capacitor shell 2 through the sealant filling port 6. During the filling of the sealant, the sealant quickly fills the gap between the capacitor shell 2 and the capacitor core 1. The air inside the capacitor shell 2 is discharged through the central exhaust mesh 12 on the bottom baffle 7 into the space enclosed by the bottom end of the capacitor shell 2 and the bottom baffle 7, and finally passes through the upper exhaust groove 16 and the side exhaust hole 17, and through the bottom exhaust vent. The groove 18 discharges air, which helps to expel air from inside the capacitor housing 2 during sealant injection. This reduces the formation of air bubbles inside the capacitor housing 2 during sealant injection, allowing the sealant to fill the inside of the capacitor housing 2 quickly. During injection, air above the capacitor housing 2 can enter the exhaust pipe 9 of the auxiliary reinforcing rib 5 and be discharged from inside the capacitor housing 2 through the exhaust pipe 9. This helps to expel air from the inside of the capacitor housing 2 during sealant injection, which can speed up the injection of the capacitor and also reduce the formation of air bubbles, thus reducing the probability of partial discharge of the electrode shell. As the amount of sealant injected into the capacitor housing 2 increases, the sealant gradually passes through the central vent mesh 12 under its own weight and accumulates on the sliding plate 11. The increased weight of the sealant on the sliding plate 11 pushes it downwards. Simultaneously, excess sealant overflows from the edge of the vent pipe 10 to one side of the movable baffle 13. The movable baffle 13 tilts towards the vent pipe 10, and the sealant flows down along the vent pipe 10 to the side vent hole 17, gradually sealing it. At the same time, the sliding plate 11 further... As the slide plate 11 descends, the air-blocking block 15 at the bottom of the sliding plate 11 blocks the bottom exhaust channel 18, thus sealing the bottom exhaust channel 18 of the capacitor housing 2. At this time, the air above the capacitor housing 2 can still enter the exhaust pipe 9 of the auxiliary reinforcing rib 5 and be discharged from the inside of the capacitor housing 2 through the exhaust pipe 9. When the sealant block is full, the sealant exceeds the top of the auxiliary reinforcing rib 5 and is discharged through the exhaust pipe 9 on the auxiliary reinforcing rib 5. When the sealant is discharged through the exhaust pipe 9, the bottom reinforcing housing 8 can be installed at the bottom of the capacitor housing 2.

[0056] In the description of this invention, it should be understood that the terms "upper," "lower," "left," and "right," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or a specific orientational structure and operation. Therefore, they should not be construed as limitations on the invention. Furthermore, "first" and "second" are only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "multiple" means two or more.

[0057] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0058] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A thin-film capacitor for reducing partial discharge in the electrode casing, characterized in that, include: The capacitor housing (2) and the housing reinforcement mechanism provided inside it; The shell reinforcement mechanism includes a main reinforcing rib (4) and two auxiliary reinforcing ribs (5). The two auxiliary reinforcing ribs (5) are located on both sides of the main reinforcing rib (4). The two sides of the main reinforcing rib (4) are connected to the inner side of the capacitor shell (2). A bottom baffle (7) is provided inside the capacitor shell (2). A capacitor core (1) is provided in the space formed by the inner side of the capacitor housing (2) and the top of the bottom baffle (7). An exhaust pipe (9) is provided inside the auxiliary reinforcing rib (5). The exhaust pipe (9) passes through the interior of the auxiliary reinforcing rib (5) and the bottom baffle (7) and extends to the bottom end of the capacitor housing (2). A central exhaust net (12) is provided in the through groove of the bottom baffle (7). The central exhaust mesh (12) is located below the main reinforcing rib (4); An exhaust pipe (10) is provided at the bottom of the inside of the capacitor housing (2). A sliding plate (11) is slidably connected inside the exhaust pipe (10). Several upper exhaust channels (16) are passed through the inside of the sliding plate (11). The bottom end of the sliding plate (11) is provided with an air block (15), and the bottom end of the capacitor housing (2) is provided with a bottom exhaust groove (18) at the corresponding position of the air block (15).

2. A thin-film capacitor for reducing partial discharge of the electrode shell according to claim 1, characterized in that, Movable baffles (13) are provided on both sides of the exhaust pipe (10). The middle part of the movable baffle (13) is installed to the inside of the baffle mounting bracket (14) via a rotating shaft. The baffle mounting bracket (14) is located at the bottom inside of the capacitor housing (2).

3. A thin-film capacitor for reducing partial discharge of the electrode shell according to claim 2, characterized in that, One side of the movable baffle (13) abuts against the side of the exhaust pipe (10).

4. A thin-film capacitor for reducing partial discharge of the electrode shell according to claim 1, characterized in that, The capacitor housing (2) is provided with a bottom end reinforcing housing (8) at the bottom end.

5. A thin-film capacitor for reducing partial discharge of the electrode shell according to claim 1, characterized in that, The capacitor housing (2) is provided with an electrode assembly (3) at its top end. The electrode assembly (3) is electrically connected to the capacitor core (1). The capacitor housing (2) is provided with a sealant injection port (6) at its top end.

6. A thin-film capacitor for reducing partial discharge of the electrode shell according to claim 1, characterized in that, The capacitor core (1) is provided in a plurality of units, and the plurality of capacitor cores (1) are arranged in an array inside the capacitor shell (2).

7. A thin-film capacitor for reducing partial discharge of the electrode shell according to claim 3, characterized in that, The exhaust pipe (10) is located below the central exhaust net (12) at the corresponding position. Side exhaust holes (17) are provided on both sides of the exhaust pipe (10). The distance between the top of the side exhaust hole (17) and the bottom surface of the capacitor housing (2) is less than the distance between the pivot position of the movable baffle (13) and the bottom surface of the capacitor housing (2).

8. A method for injecting material into a thin-film capacitor to reduce partial discharge in the electrode casing, characterized in that, Includes the following steps: S1: Before filling the capacitor, remove the bottom reinforcing shell (8) at the bottom of the capacitor shell (2); S2: Fill the inside of the capacitor housing (2) with sealant through the sealant injection port (6); S3: When the sealant is injected, the air inside the capacitor housing (2) is discharged through the middle exhaust net (12) on the bottom baffle (7) into the space enclosed by the bottom end of the capacitor housing (2) and the bottom baffle (7), and is discharged from the bottom exhaust groove (18) through the upper exhaust groove (16) and the side exhaust hole (17). The air above the capacitor housing (2) is discharged through the exhaust pipe (9). S4: During the injection of sealant, the sealant will block the upper vent groove (16) and the side vent hole (17), and the sealant will extend beyond the top of the auxiliary reinforcing rib (5) and be discharged through the vent pipe (9); S5: When the sealant is discharged from the exhaust pipe (9), the bottom reinforcing housing (8) is installed at the bottom of the capacitor housing (2).

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